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Sample records for cladding waste sludge

  1. Pretreatment of neutralized cladding removal waste sludge

    International Nuclear Information System (INIS)

    This report describes the status of process development for pretreating Hanford neutralized cladding removal waste (NCRW) sludge, of which ∼ 3.3 x 106 L is stored in Tanks 103-AW and 105-AW at the Hanford Site. The initial baseline process chosen for pretreating NCRW sludge is to dissolve the sludge in nitric acid and extract the -transuranic (MU) elements from the dissolved sludge solution with octyl(phenyl)-N,N-diisobutylcarbamoyl methyl phosphine oxide (CNWO). This process converts the NCRW sludge into a relatively large volume of low-level waste (LLW) to be disposed of as grout, leaving only a small volume of high-level waste (HLW) requiring vitrification in the Hanford Waste Vitrification Plant (HWVP)

  2. Filtration and Leach Testing for PUREX Cladding Sludge and REDOX Cladding Sludge Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Shimskey, Rick W.; Billing, Justin M.; Buck, Edgar C.; Casella, Amanda J.; Crum, Jarrod V.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Hallen, Richard T.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Swoboda, Robert G.

    2009-03-02

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan (Barnes and Voke 2006). The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Hanford Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Under test plan TP RPP WTP 467 (Fiskum et al. 2007), eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. Under this test plan, a waste testing program was implemented that included: • Homogenizing the archive samples by group as defined in the test plan. • Characterizing the homogenized sample groups. • Performing parametric leaching testing on each group for compounds of interest. • Performing bench-top filtration/leaching tests in the hot cell for each group to simulate filtration and leaching activities if they occurred in the UFP2 vessel of the WTP Pretreatment Facility. This report focuses on a filtration/leaching test performed using two of the eight waste composite samples. The sample groups examined in this report were the plutonium-uranium extraction (PUREX) cladding waste sludge (Group 3, or CWP) and reduction-oxidation (REDOX) cladding waste sludge (Group 4, or CWR). Both the Group 3 and 4 waste composites were anticipated to be high in gibbsite, thus requiring caustic leaching. WTP RPT 167 (Snow et al. 2008) describes the homogenization, characterization, and parametric leaching activities before benchtop filtration/leaching testing of these two waste groups. Characterization and initial parametric data in that report were used to plan a single filtration/leaching test using a blend of both wastes. The test focused on filtration testing of the waste and caustic leaching for aluminum, in the form

  3. Characterization and Leach Testing for PUREX Cladding Waste Sludge (Group 3) and REDOX Cladding Waste Sludge (Group 4) Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Snow, Lanee A.; Buck, Edgar C.; Casella, Amanda J.; Crum, Jarrod V.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Fiskum, Sandra K.; Jagoda, Lynette K.; Jenson, Evan D.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Swoboda, Robert G.

    2009-02-13

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan.(a) The testing program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. The actual wastetesting program included homogenizing the samples by group, characterizing the solids and aqueous phases, and performing parametric leaching tests. Two of the eight defined groups—plutonium-uranium extraction (PUREX) cladding waste sludge (Group 3, or CWP) and reduction-oxidation (REDOX) cladding waste sludge (Group 4, or CWR)—are the subjects of this report. Both the Group 3 and 4 waste composites were anticipated to be high in gibbsite, requiring caustic leaching. Characterization of the composite Group 3 and Group 4 waste samples confirmed them to be high in gibbsite. The focus of the Group 3 and 4 testing was on determining the behavior of gibbsite during caustic leaching. The waste-type definition, archived sample conditions, homogenization activities, characterization (physical, chemical, radioisotope, and crystal habit), and caustic leaching behavior as functions of time, temperature, and hydroxide concentration are discussed in this report. Testing was conducted according to TP-RPP-WTP-467.

  4. Conditioning of nuclear cladding wastes by melting

    International Nuclear Information System (INIS)

    This paper discusses a cold-crucible induction melting process to condition cladding waste from irradiated fast breeder reactor fuel. The process has been developed by the CEA at Marcoule (France) as part of a major R and D program. It has been qualified at industrial scale on nonradioactive waste, and at laboratory scale on radioactive waste: several radioactive ingots have been produced from actual stainless steel or zircaloy hulls. The results confirm the numerous advantages of this containment method

  5. Rheological evaluation of pretreated cladding removal waste

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, D.; Chan, M.K.C.; Lokken, R.O.

    1986-01-01

    Cladding removal waste (CRW) contains concentrations of transuranic (TRU) elements in the 80 to 350 nCi/g range. This waste will require pretreatment before it can be disposed of as glass or grout at Hanford. The CRW will be pretreated with a rare earth strike and solids removal by centrifugation to segregate the TRU fraction from the non-TRU fraction of the waste. The centrifuge centrate will be neutralized with sodium hydroxide. This neutralized cladding removal waste (NCRW) is expected to be suitable for grouting. The TRU solids removed by centrifugation will be vitrified. The goal of the Rheological Evaluation of Pretreated Cladding Removal Waste Program was to evaluate those rheological and transport properties critical to assuring successful handling of the NCRW and TRU solids streams and to demonstrate transfers in a semi-prototypic pumping environment. This goal was achieved by a combination of laboratory and pilot-scale evaluations. The results obtained during these evaluations were correlated with classical rheological models and scaled-up to predict the performance that is likely to occur in the full-scale system. The Program used simulated NCRW and TRU solid slurries. Rockwell Hanford Operations (Rockwell) provided 150 gallons of simulated CRW and 5 gallons of simulated TRU solid slurry. The simulated CRW was neutralized by Pacific Northwest Laboratory (PNL). The physical and rheological properties of the NCRW and TRU solid slurries were evaluated in the laboratory. The properties displayed by NCRW allowed it to be classified as a pseudoplastic or yield-pseudoplastic non-Newtonian fluid. The TRU solids slurry contained very few solids. This slurry exhibited the properties associated with a pseudoplastic non-Newtonian fluid.

  6. Rheological evaluation of pretreated cladding removal waste

    International Nuclear Information System (INIS)

    Cladding removal waste (CRW) contains concentrations of transuranic (TRU) elements in the 80 to 350 nCi/g range. This waste will require pretreatment before it can be disposed of as glass or grout at Hanford. The CRW will be pretreated with a rare earth strike and solids removal by centrifugation to segregate the TRU fraction from the non-TRU fraction of the waste. The centrifuge centrate will be neutralized with sodium hydroxide. This neutralized cladding removal waste (NCRW) is expected to be suitable for grouting. The TRU solids removed by centrifugation will be vitrified. The goal of the Rheological Evaluation of Pretreated Cladding Removal Waste Program was to evaluate those rheological and transport properties critical to assuring successful handling of the NCRW and TRU solids streams and to demonstrate transfers in a semi-prototypic pumping environment. This goal was achieved by a combination of laboratory and pilot-scale evaluations. The results obtained during these evaluations were correlated with classical rheological models and scaled-up to predict the performance that is likely to occur in the full-scale system. The Program used simulated NCRW and TRU solid slurries. Rockwell Hanford Operations (Rockwell) provided 150 gallons of simulated CRW and 5 gallons of simulated TRU solid slurry. The simulated CRW was neutralized by Pacific Northwest Laboratory (PNL). The physical and rheological properties of the NCRW and TRU solid slurries were evaluated in the laboratory. The properties displayed by NCRW allowed it to be classified as a pseudoplastic or yield-pseudoplastic non-Newtonian fluid. The TRU solids slurry contained very few solids. This slurry exhibited the properties associated with a pseudoplastic non-Newtonian fluid

  7. Chemical modeling of waste sludges

    Energy Technology Data Exchange (ETDEWEB)

    Weber, C.F.; Beahm, E.C.

    1996-10-01

    The processing of waste from underground storage tanks at the Oak Ridge National Laboratory (ORNL) and other facilities will require an understanding of the chemical interactions of the waste with process chemicals. Two aspects of sludge treatment should be well delineated and predictable: (1) the distribution of chemical species between aqueous solutions and solids, and (2) potential problems due to chemical interactions that could result in process difficulties or safety concerns. It is likely that the treatment of waste tank sludge will begin with washing, followed by basic or acidic leaching. The dissolved materials will be in a solution that has a high ionic strength where activity coefficients are far from unity. Activity coefficients are needed in order to calculate solubilities. Several techniques are available for calculating these values, and each technique has its advantages and disadvantages. The techniques adopted and described here is the Pitzer method. Like any of the methods, prudent use of this approach requires that it be applied within concentration ranges where the experimental data were fit, and its use in large systems should be preceded by evaluating subsystems. While much attention must be given to the development of activity coefficients, other factors such as coprecipitation of species and Ostwald ripening must also be considered when one aims to interpret results of sludge tests or to predict results of treatment strategies. An understanding of sludge treatment processes begins with the sludge tests themselves and proceeds to a general interpretation with the aid of modeling. One could stop with only data from the sludge tests, in which case the table of data would become an implicit model. However, this would be a perilous approach in situations where processing difficulties could be costly or result in concerns for the environment or health and safety.

  8. Process of Waste Sludge Facultative Metabolism

    Institute of Scientific and Technical Information of China (English)

    李茵

    2001-01-01

    Laboratory- scale experiments were conducted to determine new technology of waste sludge facultative metabolism . 10-L laboratory-scale facultative reactors were operated during 24-hour sludge residence time (SRT) and in room temperature . Results show that the organic matter in waste sludge after hydrolysis acidification will be reduced by 75.39%, the removal rate of CODer above 85% . Advantage of the process is hydrolysis-acidification in ambient air temperature as there is no need for facilities to be sealed or heated. In addition, the sludge will be recycled into the wastewater treatment system and finally towards zero-discharge.

  9. Waste sludge resuspension and transfer: development program

    International Nuclear Information System (INIS)

    The six Gunite waste tanks at Oak Ridge National Laboratory (ORNL) contain about 400,000 gal of sludge that has precipitated from solution and settled during the 35 years these tanks have been in service. Eventual decommissioning of the tanks has been proposed. The first part of this program is to resuspend the accumulated sludge, to transfer it to new storage tanks in Melton Valley, and to dispose of it by the shale-fracturing process. On the basis of preliminary information, a tentative operational concept was adopted. The sludge in each tank would be resuspended by hydraulic sluicing and pumped from the tank. This resuspended sludge would be treated as necessary to keep the particles in suspension and would be pumped to the new waste-storage tanks. Subsequently the sludge would be pumped from the tanks, combined with a cement-base mix, and disposed of by the shale-fracturing facility. Verification of the feasibility of this concept required development effort on characterization of the sludge and development of techniques for resuspending the sludge and for keeping it in suspension. These development efforts are described in this report. Sections of the report describe both the known properties of the sludge and the tests of grinding methods investigated, discuss tests of various suspenders, describe tests with cement-base mixes, summarize hot-cell tests on actual sludge samples, and describe tests that were made at a mockup of a Gunite tank installation. On the basis of the tests made, it was concluded that reslurrying and resuspension of the sludge is quite feasible and that the suspensions can be made compatible with cement mixes

  10. The pretreatment of intermediate level sludge and floc wastes

    International Nuclear Information System (INIS)

    A variety of sludge and floc wastes arise in the UK from the storage and reprocessing of spent fuel. These include the products of fuel cladding corrosion and various liquid effluent clean-up processes. Many of these wastes are currently stored without pre-treatment in silos, tanks and ponds. Strategies for conditioning these wastes are being developed. These are based on cement encapsulation with the products being kept in retrievable stores until suitable disposal facilities become available. The solid concentrations in the suldge and floc wastes as they arise are generally quite low. Since the volumes of wastes encapsulated in cement are largely determined by the amounts of free water retained with the wastes there are strong incentives for some form of water removal pretreatment. This would lead to cost savings through reductions in plant size and in the volumes of waste for disposal. Critical appraisals have been undertaken of the potential of a wide range of dewatering options, including thermal and filtration processes, for treating various of these intermediate level wastes. In these appraisals the performance of the total system including feeding, product transfer, process control, plant flexibility, maintenance, secondary effluent generation and treatment etc has been evaluated. This paper describes some of the more favoured processes which have been evaluated experimentally as part of these assessments

  11. Characterization Of Cladding Hull Wastes From Used Nuclear Fuels

    Directory of Open Access Journals (Sweden)

    Kang K.H.

    2015-06-01

    Full Text Available Used cladding hulls from pressurized water reactor (PWR are characterized to provide useful information for the treatment and disposal of cladding hull wastes. The radioactivity and the mass of gamma emitting nuclides increases with an increase in the fuel burn-up and their removal ratios are found to be more than 99 wt.% except Co-60 and Cs-137. In the result of measuring the concentrations of U and Pu included in the cladding hull wastes, most of the residues are remained on the surface and the removal ratio of U and Pu are revealed to be over 99.98 wt.% for the fuel burn-up of 35,000 MWd/tU. An electron probe micro-analyzer (EPMA line scanning shows that radioactive fission products are penetrated into the Zr oxide layer, which is proportional to the fuel burn-up. The oxidative decladding process exhibits more efficient removal ratio of radionuclides.

  12. Sludge washing and dissolution of Melton Valley Storage Tank waste

    International Nuclear Information System (INIS)

    Focus is on experimental and modeling R ampersand D for comprehensive sludge/supernatant processing flowsheet being done for the Underground Storage Tank Integration Demonstration; emphasis is on Hanford tank waste disposal involving dissolution of the sluge before pretreatment. Combination of tests on actual Melton Valley Storage Tank (MVST) sludge, tests on sludge simulants, and modeling of sludge chemistry provides a broad evaluation of sludge and supernate processing. The information is useful for both MVST and Hanford tank wastes

  13. Processing method and device of radioactive sludge waste

    International Nuclear Information System (INIS)

    Radioactive nuclides in a relatively highly radioactivated sludges generated from a nuclear power plant or like other facility are at first leached by using acids. Then, the leached sludge wastes are devolumed or solidified, or solidified after devoluming depending on the radioactivity level, to stabilize the sludge wastes. That is, the radioactivity of the radioactive sludge wastes is separated, to lower the radioactivity level of the radioactive sludge wastes, and they are devolumed by burning or applied with solidification of drying and solidifying into a plastic solid material or dehydrating and solidifying into a solid cement material depending on the level. Further, most of acids used for leaching the radioactive nuclides is recovered and reused. Accordingly, the amount of residual liquid wastes is decreased to a small amount and they are neutralized, and thereafter, can be stored for a long period of time as condensed liquid wastes as they are. (T.M.)

  14. Biohydrogen production using waste activated sludge disintegrated by gamma irradiation

    International Nuclear Information System (INIS)

    Highlights: • The waste activated sludge could be disintegrated by gamma irradiation. • The disintegrated sludge could be used for biohydrogen production. • Combined alkali-irradiation treatment achieved the highest solubilization of sludge. - Abstract: The biohydrogen production using the disintegrated and dissolved sludge by gamma irradiation was studied. The experimental results showed that gamma irradiation and irradiation combined with alkali pretreatment could disintegrate and dissolve waste activated sludge for biohydrogen production. The alkali-irradiation treatment of the sludge at pH = 12 and 20 kGy achieved the highest disintegration and dissolution, i.e., it could destroy the cell walls and release organic matters (such as soluble COD, polysaccharides and protein) into the solution. The disintegrated sludge could be used as a low-cost substrate for biohydrogen production

  15. Effect of microwave pre-treatment of thickened waste activated sludge on biogas production from co-digestion of organic fraction of municipal solid waste, thickened waste activated sludge and municipal sludge.

    Science.gov (United States)

    Ara, E; Sartaj, M; Kennedy, K

    2014-12-01

    Anaerobic co-digestion of organic fraction of municipal solid waste, with thickened waste activated sludge and primary sludge has the potential to enhance biodegradation of solid waste, increase longevity of existing landfills and lead to more sustainable development by improving waste to energy production. This study reports on mesophilic batch and continuous studies using different concentrations and combinations (ratios) of organic fraction of municipal solid waste, thickened waste activated sludge (microwave pre-treated and untreated) and primary sludge to assess the potential for improved biodegradability and specific biogas production. Improvements in specific biogas production for batch assays, with concomitant improvements in total chemical oxygen demand and volatile solid removal, were obtained with organic fraction of municipal solid waste:thickened waste activated sludge:primary sludge mixtures at a ratio of 50:25:25 (with and without thickened waste activated sludge microwave pre-treatment). This combination was used for continuous digester studies. At 15 d hydraulic retention times, the co-digestion of organic fraction of municipal solid waste:organic fraction of municipal solid waste:primary sludge and organic fraction of municipal solid waste:thickened waste activated sludge microwave:primary sludge resulted in a 1.38- and 1.46-fold increase in biogas production and concomitant waste stabilisation when compared with thickened waste activated sludge:primary sludge (50:50) and thickened waste activated sludge microwave:primary sludge (50:50) digestion at the same hydraulic retention times and volumetric volatile solid loading rate, respectively. The digestion of organic fraction of municipal solid waste with primary sludge and thickened waste activated sludge provides beneficial effects that could be implemented at municipal wastewater treatment plants that are operating at loading rates of less than design capacity. PMID:25398411

  16. Harvesting biogas from wastewater sludge and food waste

    Science.gov (United States)

    Chua, K. H.; Cheah, W. L.; Tan, C. F.; Leong, Y. P.

    2013-06-01

    Wastewater sludge and food waste are good source of biogas. Anaerobic treatment of slude and food waste able to produce biogas which is a potential renewable energy source. This study looks into the potential biogas generation and the effects of temperature on biogas generation. A lab scale reactor was used to simulate the biogas generation. The results show that wastewater sludge able to produced upto 44.82 ml biogas/kg of sludge. When mixed with food waste at a ratio of 30:70 (food waste), the biogas generated were 219.07 ml/kg of waste. Anaerobic of food waste alone produced biogas amount to 59.75 ml/kg of food waste. Anaerobic treatment also reduces the volume of waste. The effect of temperature shows that higher temperature produces more biogas than lower temperature.

  17. Harvesting biogas from wastewater sludge and food waste

    International Nuclear Information System (INIS)

    Wastewater sludge and food waste are good source of biogas. Anaerobic treatment of slude and food waste able to produce biogas which is a potential renewable energy source. This study looks into the potential biogas generation and the effects of temperature on biogas generation. A lab scale reactor was used to simulate the biogas generation. The results show that wastewater sludge able to produced upto 44.82 ml biogas/kg of sludge. When mixed with food waste at a ratio of 30:70 (food waste), the biogas generated were 219.07 ml/kg of waste. Anaerobic of food waste alone produced biogas amount to 59.75 ml/kg of food waste. Anaerobic treatment also reduces the volume of waste. The effect of temperature shows that higher temperature produces more biogas than lower temperature.

  18. Vitrification development for sludge and ash mixed wastes

    International Nuclear Information System (INIS)

    Preliminary glass development was carried out on four surrogate wastes. The surrogate wastes evaluated were ash and sludge from Oak Ridge National Laboratory, sludge from Rocky Flats, and sludge from Los Alamos National Laboratory. The work involved numerous melting trails followed by visual homogeneity examination and short-duration leach testing on glass specimens. Melter testing on selected compositions was performed with a laboratory-scale joule-heated furnace. With proper formulations and melter operating parameters, these mixed wastes appear to be readily adaptable to available vitrification technology

  19. Method for the treatment of waste water with sludge granules

    OpenAIRE

    van Loosdrecht, M C; De Kreuk, M.K.

    2004-01-01

    The invention relates to a method for the treatment of waste water comprising an organic nutrient. According to the invention, the waste water is in a first step fed to sludge granules, after the supply of the waste water to be treated the sludge granules are fluidised in the presence of an oxygen-comprising gas, and in a third step, the sludge granules are allowed to settle in a settling step. This makes it possible to effectively remove not only organic nutrients but optionally also nitroge...

  20. Leach test of cladding removal waste grout using Hanford groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R.J.; Martin, W.J.; Legore, V.L.

    1995-09-01

    This report describes laboratory experiments performed during 1986-1990 designed to produce empirical leach rate data for cladding removal waste (CRW) grout. At the completion of the laboratory work, funding was not available for report completion, and only now during final grout closeout activities is the report published. The leach rates serve as inputs to computer codes used in assessing the potential risk from the migration of waste species from disposed grout. This report discusses chemical analyses conducted on samples of CRW grout, and the results of geochemical computer code calculations that help identify mechanisms involved in the leaching process. The semi-infinite solid diffusion model was selected as the most representative model for describing leaching of grouts. The use of this model with empirically derived leach constants yields conservative predictions of waste release rates, provided no significant changes occur in the grout leach processes over long time periods. The test methods included three types of leach tests--the American Nuclear Society (ANS) 16.1 intermittent solution exchange test, a static leach test, and a once-through flow column test. The synthetic CRW used in the tests was prepared in five batches using simulated liquid waste spiked with several radionuclides: iodine ({sup 125}I), carbon ({sup 14}C), technetium ({sup 99}Tc), cesium ({sup 137}Cs), strontium ({sup 85}Sr), americium ({sup 241}Am), and plutonium ({sup 238}Pu). The grout was formed by mixing the simulated liquid waste with dry blend containing Type I and Type II Portland cement, class F fly ash, Indian Red Pottery clay, and calcium hydroxide. The mixture was allowed to set and cure at room temperature in closed containers for at least 46 days before it was tested.

  1. Leach test of cladding removal waste grout using Hanford groundwater

    International Nuclear Information System (INIS)

    This report describes laboratory experiments performed during 1986-1990 designed to produce empirical leach rate data for cladding removal waste (CRW) grout. At the completion of the laboratory work, funding was not available for report completion, and only now during final grout closeout activities is the report published. The leach rates serve as inputs to computer codes used in assessing the potential risk from the migration of waste species from disposed grout. This report discusses chemical analyses conducted on samples of CRW grout, and the results of geochemical computer code calculations that help identify mechanisms involved in the leaching process. The semi-infinite solid diffusion model was selected as the most representative model for describing leaching of grouts. The use of this model with empirically derived leach constants yields conservative predictions of waste release rates, provided no significant changes occur in the grout leach processes over long time periods. The test methods included three types of leach tests--the American Nuclear Society (ANS) 16.1 intermittent solution exchange test, a static leach test, and a once-through flow column test. The synthetic CRW used in the tests was prepared in five batches using simulated liquid waste spiked with several radionuclides: iodine (125I), carbon (14C), technetium (99Tc), cesium (137Cs), strontium (85Sr), americium (241Am), and plutonium (238Pu). The grout was formed by mixing the simulated liquid waste with dry blend containing Type I and Type II Portland cement, class F fly ash, Indian Red Pottery clay, and calcium hydroxide. The mixture was allowed to set and cure at room temperature in closed containers for at least 46 days before it was tested

  2. Physical Properties of Hanford Transuranic Waste Sludge

    International Nuclear Information System (INIS)

    Equipment that was purchased in the abbreviated year 1 of this project has been used during year 2 to study the fundamental behavior of materials that simulate the behavior of the Hanford transuranic waste sludge. Two significant results have been found, and each has been submitted for publication. Both studies found non-DLVO behavior in simulant systems. These separate but related studies were performed concurrently. It was previously shown in Rassat et al.'s report Physical and Liquid Chemical Simulant Formulations for Transuranic Wastes in Hanford Single-Shell Tanks that colloidal clays behave similarly to transuranic waste sludge (PNNL-14333, National Technical Information Service, U.S. Dept. of Commerce). Rassat et al. also discussed the pH and salt content of actual waste materials. It was shown that these materials exist at high pHs, generally above 10, and at high salt content, approximately 1.5 M from a mixture of different salts. A type of clay commonly studied, due to its uniformity, is a synthetic hectorite, Laponite. Therefore the work performed over the course of the last year was done mainly using suspensions of Laponite at high pH and involving high salt concentrations. One study was titled ''Relating Clay Rheology to Colloidal Parameters''. It has been submitted to the Journal of Colloid and INterface Science and is currently in the review process. The idea was to gain the ability to use measurable quantities to predict the flow behavior of clay systems, which should be similar to transuranic waste sludge. Leong et al. had previously shown that the yield stress of colloidal slurries of titania and alumina could be predicted, given the measurement of the accessible parameter zeta potential (Leong YK et al. J Chem Soc Faraday Trans, 19 (1993) 2473). Colloidal clays have a fundamentally different morphology and surface charge distribution than the spheroidal, uniformly charged colloids previously studied. This study was therefore performed in order to

  3. Co-digestion of pig slaughterhouse waste with sewage sludge.

    Science.gov (United States)

    Borowski, Sebastian; Kubacki, Przemysław

    2015-06-01

    Slaughterhouse wastes (SHW) are potentially very attractive substrates for biogas production. However, mono-digestion of these wastes creates great technological problems associated with the inhibitory effects of ammonia and fatty acids on methanogens as well as with the foaming in the digesters. In the following study, the co-digestion of slaughterhouse wastes with sewage sludge (SS) was undertaken. Batch and semi-continuous experiments were performed at 35°C with municipal sewage sludge and pig SHW composed of meat tissue, intestines, bristles and post-flotation sludge. In batch assays, meat tissue and intestinal wastes gave the highest methane productions of 976 and 826 dm(3)/kg VS, respectively, whereas the methane yield from the sludge was only 370 dm(3)/kg VS. The co-digestion of sewage sludge with 50% SHW (weight basis) provided the methane yield exceeding 600 dm(3)/kg VS, which was more than twice as high as the methane production from sewage sludge alone. However, when the loading rate exceeded 4 kg VS/m(3) d, a slight inhibition of methanogenesis was observed, without affecting the digester stability. The experiments showed that the co-digestion of sewage sludge with large amount of slaughterhouse wastes is feasible, and the enhanced methane production does not affect the digester stability. PMID:25840737

  4. Biodegradation of waste PET based copolyesters in thermophilic anaerobic sludge

    Czech Academy of Sciences Publication Activity Database

    Hermanová, S.; Šmejkalová, P.; Merna, J.; Zarevúcka, Marie

    2015-01-01

    Roč. 111, Jan (2015), s. 176-184. ISSN 0141-3910 Institutional support: RVO:61388963 Keywords : poly(ethylene terephthalate) * copolymers * sludge * biodegradation * hydrolysis * waste Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.163, year: 2014

  5. Ultrasonic waste activated sludge disintegration for improving anaerobic stabilization.

    Science.gov (United States)

    Tiehm, A; Nickel, K; Zellhorn, M; Neis, U

    2001-06-01

    The pretreatment of waste activated sludge by ultrasonic disintegration was studied in order to improve the anaerobic sludge stabilization. The ultrasound frequency was varied within a range from 41 to 3217 kHz. The impact of different ultrasound intensities and treatment times was examined. Sludge disintegration was most significant at low frequencies. Low-frequency ultrasound creates large cavitation bubbles which upon collapse initiate powerful jet streams exerting strong shear forces in the liquid. The decreasing sludge disintegration efficiency observed at higher frequencies was attributed to smaller cavitation bubbles which do not allow the initiation of such strong shear forces. Short sonication times resulted in sludge floc deagglomeration without the destruction of bacteria cells. Longer sonication brought about the break-up of cell walls, the sludge solids were distintegrated and dissolved organic compounds were released. The anaerobic digestion of waste activated sludge following ultrasonic pretreatment causing microbial cell lysis was significantly improved. There was an increase in the volatile solids degradation as well as an increase in the biogas production. The increase in digestion efficiency was proportional to the degree of sludge disintegration. To a lesser degree the deagglomeration of sludge flocs also augmented the anaerobic volatile solids degradation. PMID:11337847

  6. Enzyme Activities in Waste Water and Activated Sludge

    DEFF Research Database (Denmark)

    Nybroe, Ole; Jørgensen, Per Elberg; Henze, Mogens

    1992-01-01

    measured as colony forming units of heterotrophic bacteria. A panel of four enzyme activity assays, α-glucosidase, alanine-aminopeptidase, esterase and dehydrogenase were used to characterize activated sludge and anaerobic hydrolysis sludge from a pilot scale plant. The enzymatic activity profiles were...... distinctly different, suggesting that microbial populations were different, or had different physiological properties, in the two types of sludge. Enzyme activity profiles in activated sludge from four full-scale plants seemed to be highly influenced by the composition of the inlet. Addition of hydrolysed......The purpose of the present study was to evaluate the potential of selected enzyme activity assays to determine microbial abundance and heterotrophic activity in waste water and activated sludge. In waste water, esterase and dehydrogenase activities were found to correlate with microbial abundance...

  7. Enzyme Activities in Waste Water and Activated Sludge

    DEFF Research Database (Denmark)

    Nybroe, Ole; Jørgensen, Per Elberg; Henze, Mogens

    1992-01-01

    The purpose of the present study was to evaluate the potential of selected enzyme activity assays to determine microbial abundance and heterotrophic activity in waste water and activated sludge. In waste water, esterase and dehydrogenase activities were found to correlate with microbial abundance...... measured as colony forming units of heterotrophic bacteria. A panel of four enzyme activity assays, α-glucosidase, alanine-aminopeptidase, esterase and dehydrogenase were used to characterize activated sludge and anaerobic hydrolysis sludge from a pilot scale plant. The enzymatic activity profiles were...... distinctly different, suggesting that microbial populations were different, or had different physiological properties, in the two types of sludge. Enzyme activity profiles in activated sludge from four full-scale plants seemed to be highly influenced by the composition of the inlet. Addition of hydrolysed...

  8. Irradiation of sewage sludge and waste water

    International Nuclear Information System (INIS)

    The aim of this investigaton was to establish how the chemico-physical nature of sewage sludge varies with irradiation dose and circulaton frequency. For aerobically-stable sludge, irradiation treatment was found to improve settling, whereas dehydration was impaired. Irradiation achieved an approx. 20% improvement in dehydration for anaerobically stable sewage from a non-heated fermentation room. Filtration resistance and the amount of organic flocculant required deteriorated, however. For anaerobic sludge from a heated fermentation room, settling behaviour improved by 10%, specific filtration resistance by 50% and dehyration by as much as 80% upon irradiation. A radiation dose greater than 300 krad (3000 T/kg) was however necessary. The amount of organic flocculant required remained uncharged and at the same time more favourable settling and filtering characteristics of the sludge could be observed. Increase in dry matter of the liquid sludge on irradiation was caused to same 60-95% by suspended matter (> 0.45 μm). Increasing circulation frequency led, in general, to a deterioration in the sludge characteristics of all treated sludges. In order to achieve a dose distribution as homogenous as possible, irradiation should be carried out with a medium circulation frequency of approx. 1.5 rotations/min. Irradiated sewage sludge had more favourable physical properties compared to pasteurisation and had no repugnant odor. Provided sufficient inoculating sludge is added to raw sewage, irradiation treatment does not affect the fermentation gas production. Irradiated sludge exhibited a slightly more favourable settling and filtration behaviour. (orig./MG)

  9. Waste Acceptance for Vitrified Sludge from Oak Ridge Tank Farms

    International Nuclear Information System (INIS)

    The Tanks Focus Area of the DOE's Office of Science and Technology (EM-50) has funded the Savannah River Technology Center (SRTC) to develop formulations which can incorporate sludges from Oak Ridge Tank Farms into immobilized glass waste forms. The four tank farms included in this study are: Melton Valley Storage Tanks (MVST), Bethel Valley Evaporation Service Tanks (BVEST), Gunite and Associated Tanks (GAAT), and Old Hydrofracture Tanks (OHF).The vitrified waste forms must be sent for disposal either at the Waste Isolation Pilot Plant (WIPP) or the Nevada Test Site (NTS). Waste loading in the glass is the major factor in determining where the waste will be sent and whether the waste will be remote-handled (RH) or contact-handled (CH). In addition, the waste loading significantly impacts the costs of vitrification operations and transportation to and disposal within the repository.This paper focuses on disposal options for the vitrified Oak Ridge Tank sludge waste as determined by the WIPP (1) and NTS (2) Waste Acceptance Criteria (WAC). The concentrations for both Transuranic (TRU) and beta/gamma radionuclides in the glass waste form will be presented a a function of sludge waste loading. These radionuclide concentrations determine whether the waste forms will be TRU (and therefore disposed of at WIPP) and whether the waste forms will be RH or CH

  10. Characterization of Radionuclides in Waste Sludges from High Level Waste Tanks 40, 42, and 51

    International Nuclear Information System (INIS)

    This document will develop a radionuclide distribution for the sludge fraction of sludge-contaminated waste stored in High Level Waste Tanks 40, 42 and 51 in accordance with the methodology outlined in WAC 2.02 (Rev. 4). A single, comprehensive characterization for supernate has been developed previously (Reference 5). This distribution is based on the assumption that sludge-contaminated waste from tanks 40, 42 and 51 may be co-mingled, and the actual contamination present on waste in a series of containers from these tanks will be representative of the mean radionuclide distribution. This document also describes the methodology for application of radionuclide distributions representative of the sludge and supernate fractions of sludge-contaminated waste to individual waste packages

  11. Using Boiling for Treating Waste Activated Sludge

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this work we investigated the feasibility of using short time, low superheat boiling to treat biological sludge. The treated sludge exhibited reduced filterability and enhanced settleability. The boiling treatment released a large amount of extra-cellular polymers (ECPs) from the solid phase and reduced the microbial density levels of the total coliform bacteria and the heterotrophic bacteria. A diluted sludge is preferable for its high degree of organic hydrolysis and sufficient reduction in microbial density levels.

  12. Brief assessment of some technical and radiological hazard factors affecting clad waste management

    Energy Technology Data Exchange (ETDEWEB)

    Zima, G.E.

    1976-07-30

    In the management of the adverse byproducts of nuclear energy, the general problem is centered in the post-reactor discharge phases. Various waste streams are generated in the reprocessing and fuel manufacturing plants which add both volume and physicochemical diversity to the nuclear fuel waste management problem. Of these streams, the high level waste (HLW) and the clad waste streams carry the principal radiological hazard and thermal power burdens when considering post reactor-discharge times in excess of roughly a year and reasonable contamination factors. In order to measure the relative importance of the high level and clad waste streams within the context of a reasonable nuclear power scenario, various technical and hazard indices are compared for the light water, enriched uranium fueled, reactor (LWR(U)). For the clad waste, two fuel models are used for the volume comparison: the Reference Fuel Assembly (RFA) and the Diablo Canyon reference fuel model (DC). The more extensive data available for the Diablo Canyon model on radioactivity and thermal power are used in the comparison of these indices. Most of this review pertains to a burnup of 33GWD/MT. A brief analysis is given of the effect of burnup and fuel model on certain clad waste characteristics. This report is submitted as a preliminary to technico-economic considerations of clad waste. (DLC)

  13. The digestibility of waste activated sludges.

    Science.gov (United States)

    Park, Chul; Abu-Orf, Mohammad M; Novak, John T

    2006-01-01

    Laboratory digestion studies using waste activated sludges (WAS) were conducted to compare the digestion performance between anaerobic and aerobic processes. Nine samples of WAS from seven wastewater treatment plants were collected and batch-digested under both anaerobic and aerobic conditions for 30 days at 25 degrees C. The cation content of wastewater (both floc and solution phases) and solution biopolymer (protein and polysaccharide) was measured before and after digestion and compared with volatile solids destruction data. The study revealed that each digestion process was associated with a distinct biopolymer fraction, which accounted for differences in volatile solids reduction under anaerobic and aerobic conditions. The anaerobic digestion data showed strong correlations between soluble protein generation, ammonium production, percent volatile solids reduction, and floc iron (Fe). These data suggest that the amount of volatile solids destroyed by anaerobic digestion depends on the Fe content of floc. In aerobic digestion, polysaccharide accumulated in solution along with calcium and magnesium. For aerobic digestion, correlations between divalent cation release and the production of inorganic nitrogen were found. This implies that divalent cation-bound biopolymer, thought to be lectin-like protein, was the primary organic fraction degraded under aerobic conditions. The results of the study show that the cation content in wastewater is an important indicator of the material that will digest under anaerobic or aerobic conditions and that some of the volatile solids will digest only under either anaerobic or aerobic conditions. PMID:16553167

  14. High Level Waste System Impacts from Acid Dissolution of Sludge

    Energy Technology Data Exchange (ETDEWEB)

    KETUSKY, EDWARD

    2006-04-20

    This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.

  15. Study on characteristics of spent PWR cladding hull for categorizing into Non-TRU waste

    International Nuclear Information System (INIS)

    AFCI and GEN-IV programs aim for decreasing the high level radioactive wastes to be disposed. They also try to get valuable materials to recycle as resources such as uranium and plutonium. On the other hand, cladding hull expected to be one-thirds in volume of spent fuel assembly has not studied so much in the point view of recycling to reuse. Since traditional process of reprocessing was wet process, cladding hull generating through the reprocessing process was unavoidably contaminated with TRU by acid solvent during the process. Therefore, cladding hull has been classified into TRU wastes or high level wastes. According to the strategy for TRU high level radioactive wastes of USA as well as Korea, it regulates in two respects. One is activity and the other is heat generation. In respect of activity, TRU waste contains more than 100 nCi/kg of alpha emits with longer half life than 20 years and higher than 92 in atomic number. Also, wastes are categorized into TRU waste when it generates higher than 2kW/m3, in the respect of heat generation. Our results as well as literatures, almost all of TRU nuclides in the cladding hull are responsible for remained uranium and plutonium owing to pellet-cladding interaction. In addition, recoiled fission products on the surface of the cladding hull serve as heat generator. Up to now, decontamination of the cladding hull generating from the reprocessing of wet process is regarded as valueless and un-economic works owing to the amount of second waste produced

  16. Handling 78,000 drums of mixed-waste sludge

    International Nuclear Information System (INIS)

    The Oak Ridge Gaseous Diffusion Plant (now know as the Oak Ridge K-25 Site) prepared two mixed-waste surface impoundments for closure by removing the sludge and contaminated pond-bottom clay and attempting to process it into durable, nonleachable, concrete monoliths. Interim, controlled, above-ground storage of the stabilized waste was planned until final disposition. The strategy for disposal included delisting the stabilized pond sludge from hazardous to nonhazardous and disposing of the delisted monoliths as radioactive waste. Because of schedule constraints and process design and control deficiencies, ∼46,000 drums of material in various stages of solidification and ∼32,000 drums of unprocessed sludge are presently being stored. In addition, the abandoned treatment facility still contains ∼16,000 gal of raw sludge. Such conditions do not comply with the requirements set forth by the Resource Conservation and Recovery Act (RCRA) for the storage of listed waste. Various steps are being taken to bring the storage of ∼78,000 drums of mixed waste into compliance with RCRA. This paper (1) reviews the current situation, (2) discusses the plan for remediation of regulatory noncompliances, including decanting liquid from stabilized waste and dewatering untreated waste, and (3) provides an assessment of alternative raw-waste treatment processes. 1 ref., 6 figs., 2 tabs

  17. Production of bacterial cellulose and enzyme from waste fiber sludge

    OpenAIRE

    Cavka, Adnan; Guo, Xiang; Tang, Shui-Jia; Winestrand, Sandra; Jönsson, Leif J.; Hong, Feng

    2013-01-01

    Background: Bacterial cellulose (BC) is a highly crystalline and mechanically stable nanopolymer, which has excellent potential as a material in many novel applications, especially if it can be produced in large amounts from an inexpensive feedstock. Waste fiber sludge, a residue with little or no value, originates from pulp mills and lignocellulosic biorefineries. A high cellulose and low lignin content contributes to making the fiber sludge suitable for bioconversion, even without a thermoc...

  18. Thermoradiation treatment of sewage sludge using reactor waste fission products

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, M. C.; Hagengruber, R. L.; Zuppero, A. C.

    1974-06-01

    The hazards to public health associated with the application of municipal sewage sludge to land usage are reviewed to establish the need for disinfection of sludge prior to its distribution as a fertilizer, especially in the production of food and fodder. The use of ionizing radiation in conjunction with mild heating is shown to be an effective disinfection treatment and an economical one when reactor waste fission products are utilized. A program for researching and experimental demonstration of the process on sludges is also outlined.

  19. Thermoradiation treatment of sewage sludge using reactor waste fission products

    International Nuclear Information System (INIS)

    The hazards to public health associated with the application of municipal sewage sludge to land usage are reviewed to establish the need for disinfection of sludge prior to its distribution as a fertilizer, especially in the production of food and fodder. The use of ionizing radiation in conjunction with mild heating is shown to be an effective disinfection treatment and an economical one when reactor waste fission products are utilized. A program for researching and experimental demonstration of the process on sludges is also outlined

  20. Hygienization of sewage sludge with radioactive waste material

    International Nuclear Information System (INIS)

    A special irradiation plant in Geiselbullach (Federal Republic of Germany) has recently been charged up with caesium 137 sources. This is the first time that highly radioactive waste products from nuclear power stations are being employed for the hygienization of sewage sludge. About 150 m3 of sewage sludge per day are subjected for a short time to irradiation by hard gamma rays in the Geiselbullach plant. The irradiation destroys the living organisms dangerous to human health present in the sludge. This results in an end product used as fertilizer in agriculture. (Auth.)

  1. Stabilization of a mixed waste sludge for land disposal

    International Nuclear Information System (INIS)

    A solidification and stabilization technique was developed for a chemically complex mixed waste sludge containing nitrate processing wastes, sewage sludge and electroplating wastewaters, among other wastes. The sludge is originally from a solar evaporation pond and has high concentrations of nitrate salts; cadmium, chromium, and nickel concentrations of concern; and low levels of organic constituents and alpha and beta emitters. Sulfide reduction of nitrate and precipitation of metallic species, followed by evaporation to dryness and solidification of the dry sludge in recycled high density polyethylene with added lime was determined to be a satisfactory preparation for land disposal in a mixed waste repository. The application of post-consumer polyethylene has the added benefit of utilizing another problem-causing waste product. A modified Toxicity Characteristic Leaching Procedure was used to determine required treatment chemical dosages and treatment effectiveness. The waste complexity prohibited use of standard chemical equilibrium methods for prediction of reaction products during treatment. Waste characterization followed by determination of thermodynamic feasibility of oxidation and reduction products. These calculations were shown to be accurate in laboratory testing. 13 refs., 3 figs., 2 tabs

  2. Anaerobic bioleaching of metals from waste activated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Meulepas, Roel J.W., E-mail: roel.meulepas@wetsus.nl [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Gonzalez-Gil, Graciela [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Teshager, Fitfety Melese; Witharana, Ayoma [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Saikaly, Pascal E. [King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Lens, Piet N.L. [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands)

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g{sup −1} of copper, 487 μg g{sup −1} of lead, 793 μg g{sup −1} of zinc, 27 μg g{sup −1} of nickel and 2.3 μg g{sup −1} of cadmium. During the anaerobic acidification of 3 g{sub dry} {sub weight} L{sup −1} waste activated sludge, 80–85% of the copper, 66–69% of the lead, 87% of the zinc, 94–99% of the nickel and 73–83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. - Highlights: • Heavy metals were leached during anaerobic acidification of waste activated sludge. • The process does not require the addition of chelating or oxidizing agents. • The metal leaching efficiencies (66 to 99%) were comparable to chemical leaching. • The produced leachate may be used for metal recovery and biogas production. • The produced digested sludge may be used as soil conditioner.

  3. Anaerobic bioleaching of metals from waste activated sludge

    International Nuclear Information System (INIS)

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g−1 of copper, 487 μg g−1 of lead, 793 μg g−1 of zinc, 27 μg g−1 of nickel and 2.3 μg g−1 of cadmium. During the anaerobic acidification of 3 gdry weight L−1 waste activated sludge, 80–85% of the copper, 66–69% of the lead, 87% of the zinc, 94–99% of the nickel and 73–83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. - Highlights: • Heavy metals were leached during anaerobic acidification of waste activated sludge. • The process does not require the addition of chelating or oxidizing agents. • The metal leaching efficiencies (66 to 99%) were comparable to chemical leaching. • The produced leachate may be used for metal recovery and biogas production. • The produced digested sludge may be used as soil conditioner

  4. Anaerobic bioleaching of metals from waste activated sludge

    KAUST Repository

    Meulepas, Roel J W

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342μgg-1 of copper, 487μgg-1 of lead, 793μgg-1 of zinc, 27μgg-1 of nickel and 2.3μgg-1 of cadmium. During the anaerobic acidification of 3gdry weightL-1 waste activated sludge, 80-85% of the copper, 66-69% of the lead, 87% of the zinc, 94-99% of the nickel and 73-83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead.

  5. Anaerobic bioleaching of metals from waste activated sludge.

    Science.gov (United States)

    Meulepas, Roel J W; Gonzalez-Gil, Graciela; Teshager, Fitfety Melese; Witharana, Ayoma; Saikaly, Pascal E; Lens, Piet N L

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g(-1) of copper, 487 μg g(-1) of lead, 793 μg g(-1) of zinc, 27 μg g(-1) of nickel and 2.3 μg g(-1) of cadmium. During the anaerobic acidification of 3 gdry weight L(-1) waste activated sludge, 80-85% of the copper, 66-69% of the lead, 87% of the zinc, 94-99% of the nickel and 73-83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. PMID:25659306

  6. Anaerobic co-digestion of sewage sludge and food waste.

    Science.gov (United States)

    Prabhu, Meghanath S; Mutnuri, Srikanth

    2016-04-01

    Anaerobic co-digestion of organic matter improves digester operating characteristics and its performance. In the present work, food waste was collected from the institute cafeteria. Two types of sludge (before centrifuge and after centrifuge) were collected from the fluidised bed reactor of the institute treating sewage wastewater. Food waste and sludge were studied for their physico-chemical characteristics, such as pH, chemical oxygen demand, total solids, volatile solids, ammoniacal nitrogen, and total nitrogen. A biomethane potential assay was carried out to find out the optimum mixing ratio of food waste and sludge for anaerobic co-digestion. Results indicated that food waste mixed with sludge in the ratio of 1:2 produced the maximum biogas of 823 ml gVS(-1)(21 days) with an average methane content of 60%. Batch studies were conducted in 5 L lab-glass reactors at a mesophilic temperature. The effect of different substrate loading rates on biogas production was investigated. The mixing ratio of food waste and sludge was 1:2. A loading rate of 1 gVS L d(-1)gave the maximum biogas production of 742 ml g(-1)VS L d(-1)with a methane content of 50%, followed by 2 gVS L d(-1)with biogas of 539 ml g(-1)VS L d(-1) Microbial diversity of the reactor during fed batch studies was investigated by terminal restriction fragment length polymorphism. A pilot-scale co-digestion of food waste and sludge (before centrifuge) indicated the process stability of anaerobic digestion. PMID:26879909

  7. Potential Biogas Production from Fish Waste and Sludge.

    OpenAIRE

    Shi, Chen

    2012-01-01

    In order to decrease the pollution of the marine environment from dumping fish waste and by-catch, alternative use for co-digestion with sludge in anaerobic condition was studied. The purpose of this project is to optimize the methane potential from adjustment of the proportion among mixed substrates. Ten groups of different proportions among fish waste, by-catch and sludge were conducted with AMPTS II instrument under mesophilic condition (37 ± 0.5 ºC), by means of the principle of BMP test....

  8. Nitrogen in the Process of Waste Activated Sludge Anaerobic Digestion

    Directory of Open Access Journals (Sweden)

    Suschka Jan

    2014-07-01

    Full Text Available Primary or secondary sewage sludge in medium and large WWTP are most often processed by anaerobic digestion, as a method of conditioning, sludge quantity minimization and biogas production. With the aim to achieve the best results of sludge processing several modifications of technologies were suggested, investigated and introduced in the full technical scale. Various sludge pretreatment technologies before anaerobic treatment have been widely investigated and partially introduced. Obviously, there are always some limitations and some negative side effects. Selected aspects have been presented and discussed. The problem of nitrogen has been highlighted on the basis of the carried out investigations. The single and two step - mesophilic and thermophilic - anaerobic waste activated sludge digestion processes, preceded by preliminary hydrolysis were investigated. The aim of lab-scale experiments was pre-treatment of the sludge by means of low intensive alkaline and hydrodynamic disintegration. Depending on the pretreatment technologies and the digestion temperature large ammonia concentrations, up to 1800 mg NH4/dm3 have been measured. Return of the sludge liquor to the main sewage treatment line means additional nitrogen removal costs. Possible solutions are discussed.

  9. Colloidal agglomerates in tank sludge: Impact on waste processing

    International Nuclear Information System (INIS)

    'Insoluble colloidal sludges in hazardous waste streams such as tank wastes can pose serious problems for waste processing, interfering with retrieval, transport, separation, and solidification procedures. Properties of sediment layers and sludge suspensions such as slurry viscosities, sedimentation rates, and final sediment densities can vary by orders of magnitude depending on the particle types present, the degree to which the particles agglomerate or stick to each other, and on a wide range of processing parameters such as solution shear rates, pH, salt content, and temperature. The objectives of this work are to: (1) understand the factors controlling the nature and extent of colloidal agglomeration under expected waste processing conditions; (2) determine how agglomeration phenomena influence physical properties relevant to waste processing including rheology, sedimentation, and filtration; and (3) develop strategies for optimizing processing conditions via control of agglomeration phenomena. Insoluble colloidal sludges in hazardous waste streams such as tank wastes can pose serious problems for waste processing, interfering with retrieval, transport, separation, and solidification procedures. Properties of sediment layers and sludge suspensions such as slurry viscosities, sedimentation rates, and final sediment densities can vary by orders of magnitude depending on the particle types present, the degree to which the particles agglomerate or stick to each other, and on a wide range of processing parameters such as solution shear rates, pH, salt content, and temperature. The objectives of this work are to: (1) understand the factors controlling the nature and extent of colloidal agglomeration under expected waste processing conditions; (2) determine how agglomeration phenomena influence physical properties relevant to waste processing including rheology, sedimentation, and filtration; and (3) develop strategies for optimizing processing conditions via control

  10. Vitrification treatability studies of actual waste water treatment sludges

    International Nuclear Information System (INIS)

    Treatability studies have been conducted at the laboratory-scale to evaluate vitrification of waste water sludges at the Oak Ridge Reservation (ORR). These studies are being conducted jointly by Westinghouse Savannah River Technology Center (SRTC) and Oak Ridge National Laboratory (ORNL). These studies include testing with surrogate waste formulations at both the laboratory-scale and pilot-scale, and testing with actual waste at the laboratory-scale, pilot-scale, and field-scale. ORR was chosen as the host site for the field-scale demonstration. The Y12 West End Treatment Facility (WETF) waste water treatment sludges, which are RCRA F-listed wastes, were chosen as the candidate waste stream for the first field-scale demonstration. The laboratory-scale ''proof-of-principle'' demonstrations reported in this study and the pilot-scale studies planned for FY95 on the WETF sludge will provide needed operating parameters for the planned field-scale demonstration. These laboratory-scale ''proof-of-principle'' and pilot-scale studies also provide needed data for the evaluation of the feasibility of vitrification as a stabilization option for a variety of wastes which do not currently meet RCRA/LDR (Resource Conservation and Recovery Act/Land Disposal Restrictions) requirements for storage/disposal and/or those for which treatment capacity does not presently exist

  11. Incorporation of fine steel sludge waste into red ceramic

    International Nuclear Information System (INIS)

    This work has as its objective to evaluate the effect of incorporation of fine steel sludge waste on the properties and microstructure of a kaolinitic clay used to fabricate bricks and roofing tiles. Characterization tests of the steel sludge employed X-ray diffraction, chemical composition, particle size distribution, scanning electron microscopy and DTA/TG analysis. Compositions were prepared with additions of 0, 5, 10 and 20 wt.% waste in a kaolinitic clay from Brazil. To determine the technological properties such as bulk density, linear shrinkage, water absorption and flexural strength, press molded specimens were fired in laboratory furnace at 900 deg. C. The microstructure of the fired specimens was evaluated by SEM and XRD. The results showed that incorporations up to 5 wt.% of fine steel sludge is beneficial to the red ceramic. By contrast, incorporations above 5 wt.% cause deleterious effect on the mechanical strength of the fired specimens

  12. Handling 78,000 drums of mixed-waste sludge

    International Nuclear Information System (INIS)

    The Oak Ridge Gaseous Diffusion Plant (now known as the Oak Ridge K-25 Site) closed two mixed-waste surface impoundments by removing the sludge and contaminated pond-bottom clay and attempting to process it into durable, nonleachable, concrete monoliths. Interim, controlled, above-ground storage included delisting the stabilized sludge from hazardous to nonhazardous and disposing of the delisted monoliths as Class 1 radioactive waste. Because of schedule constraints and process design and control deficiencies, ∼46,000 drums of material in various stages of solidification and ∼32,000 barrels of unprocessed sludge are stored. The abandoned treatment facility still contains ∼16,000 gal of raw sludge. Such storage of mixed waste does not comply with the Resource Conservation and Recovery Act (RCRA) guidelines. This paper describes actions that are under way to bring the storage of ∼78,000 drums of mixed waste into compliance with RCRA. Remediation of this problem by treatment to meet regulatory requirements is the focus of the discussion. 3 refs., 2 figs., 4 tabs

  13. Construction materials as a waste management solution for cellulose sludge

    International Nuclear Information System (INIS)

    Sustainable waste management system for effluents treatment sludge has been a pressing issue for pulp and paper sector. Recycling is always recommended in terms of environmental sustainability. Following an approach of waste valorisation, this work aims to demonstrate the technical viability of producing fiber-cement roof sheets incorporating cellulose primary sludge generated on paper and pulp mills. From the results obtained with preliminary studies it was possible to verify the possibility of producing fiber-cement sheets by replacing 25% of the conventional used virgin long fiber by primary effluent treatment cellulose sludge. This amount of incorporation was tested on an industrial scale. Environmental parameters related to water and waste, as well as tests for checking the quality of the final product was performed. These control parameters involved total solids in suspension, dissolved salts, chlorides, sulphates, COD, metals content. In the product, parameters like moisture, density and strength were controlled. The results showed that it is possible to replace the virgin long fibers pulp by primary sludge without impacts in final product characteristics and on the environment. This work ensures the elimination of significant waste amounts, which are nowadays sent to landfill, as well as reduces costs associated with the standard raw materials use in the fiber-cement industrial sector.

  14. Potential uses of Waste Sludge in Construction Industry: A Review

    Directory of Open Access Journals (Sweden)

    O.A. Johnson

    2014-07-01

    Full Text Available Waste generation and management is becoming a global challenge resulting into increased environmental concern. Waste management and recycle into a sustainable construction materials as proved to be an alternative for waste disposal helping out in the area of environmental pollution and economic. In recent years various type of waste has been used/reused in the development of sustainable construction materials. This study reviews various attempts that have been made to use sludge from different plants in construction industry. The mechanical and physical properties of the products, the environmental effect of the products and possible recommendations for future research was presented in the review.

  15. Reactor waste utilization in sewage sludge treatment

    International Nuclear Information System (INIS)

    This paper deals with inactivation of sewage pathogens by means of heat and γ radiation, either singly or simultaneously (thermoradiation). Bacteria, viruses, and Ascaris were studied. Chemical and physical effects on the sludges were also studied. A 137Cs facility is under development

  16. Continuous biohydrogen production from waste bread by anaerobic sludge.

    Science.gov (United States)

    Han, Wei; Huang, Jingang; Zhao, Hongting; Li, Yongfeng

    2016-07-01

    In this study, continuous biohydrogen production from waste bread by anaerobic sludge was performed. The waste bread was first hydrolyzed by the crude enzymes which were generated by Aspergillus awamori and Aspergillus oryzae via solid-state fermentation. It was observed that 49.78g/L glucose and 284.12mg/L free amino nitrogen could be produced with waste bread mass ratio of 15% (w/v). The waste bread hydrolysate was then used for biohydrogen production by anaerobic sludge in a continuous stirred tank reactor (CSTR). The optimal hydrogen production rate of 7.4L/(Ld) was achieved at chemical oxygen demand (COD) of 6000mg/L. According to the results obtained from this study, 1g waste bread could generate 0.332g glucose which could be further utilized to produce 109.5mL hydrogen. This is the first study which reports continuous biohydrogen production from waste bread by anaerobic sludge. PMID:27065225

  17. Evaluation of water treatment sludge for ameliorating acid mine waste.

    Science.gov (United States)

    Van Rensburg, L; Morgenthal, T L

    2003-01-01

    This study investigated the liming effect of water treatment sludge on acid mine spoils. The study was conducted with sludge from a water purification plant along the Vaal River catchments in South Africa. The optimum application rate for liming acid spoils and the speed and depth with which the sludge reacted with the mine waste were investigated. Chemical analysis indicated that the sludge is suitable as a liming agent because of its alkaline pH (8.08), high bicarbonate concentration (183.03 mg L(-1)), and low salinity (electrical conductivity = 76 mS m(-1)). The high cation exchange capacity of 15.47 cmol(c) kg(-1) and elevated nitrate concentration (73.16 mg L(-1)) also increase its value as an ameliorative material. The soluble concentrations for manganese, aluminum, lead, and selenium were high at a pH of 5 although only selenium (0.83 mg L(-1)) warranted some concern. According to experimental results, the application of 10 Mg ha(-1) of sludge to acid gold tailings increased the leach water pH from 4.5 to more than 7.5 and also increased the medium pH from 2.4 to 7.5. The addition of sludge further reduced the solubility of iron, manganese, copper, and zinc in the ameliorated gold tailings, but increased the electrical conductivity. The liming tempo was highest in the coal discard profile that had a coarse particle size distribution and took the longest to move through the gold tailings that had a fine particle size distribution. Results from this study indicate that the water treatment sludge investigated is suitable as a liming agent for rehabilitation of acid mine waste. PMID:14535306

  18. Chemical characterization of SRP waste tank sludges and supernates

    International Nuclear Information System (INIS)

    Most high-level liquid wastes at the Savannah River Plant (SRP) are byproducts from plutonium and enriched uranium recovery processes. The high-level liquid wastes generated by these separations processes are stored in large, underground, carbon-steel tanks. The liquid wastes consist of: supernate (an aqueous solution containing sodium, nitrate, nitrite, hydroxyl, and aluminate ions), sludge (a gelatinous material containing insoluble components of the waste, such as ferric and aluminum hydroxides, and mercuric and manganese oxides), and salt cake (crystals, such as sodium nitrate, formed by evaporation of water from supernate). Analyses of SRP wastes by laser-Raman spectrometry, atomic absorption spectrometry, spark-source mass spectrometry, neutron activation analysis, colorimetry, ion chromatography, and various other wet-chemical and radiochemical methods are discussed. These analyses are useful in studies of waste tank corrosion and of forms for long-term waste storage

  19. Prediction of centrifugal pump-cleaning ability in waste sludge

    International Nuclear Information System (INIS)

    Radioactive waste at the Savannah River Plant (SRP) is being transferred from older waste tanks to new, stress-relieved tanks for more effective waste management. The technology developed for waste removal involves the use of long-shaft, recirculating, centrifugal pumps (slurry pumps). Testing completed at the Savannah River Laboratory's 30-meter-diameter mock-up waste tank related the effective cleaning radius (ECR) of a slurry pump to critical pump and materials characteristics. Presently, this theory is being applied to radioactive waste at SRP. However, the technology can be applied to other remote handling situations where the slurry rheology can be determined. For SRP waste, an equation of the form: ECR α DV0 (rho/tau0)/sup 1/2/ was determined where D is the nozzle diameter, V0 is the average initial velocity, rho is the density of the slurry, and tau0 is the yield stress of the slurry. Using this relationship, the cleaning performance of a pump operating in any SRP sludge environment can be predicted. Specifically, yield stress and density measurements on sludge samples can be used to predict the required number and effective location for slurry pumps in actual SRP waste tanks

  20. Anaerobic co-digestion of coffee waste and sewage sludge

    OpenAIRE

    Neves, L.; Oliveira, Rosário; Alves, M. M.

    2006-01-01

    The feasibility of the anaerobic co-digestion of coffee solid waste and sewage sludge was assessed. Five different solid wastes with different chemical properties were studied in mesophilic batch assays, providing basic data on the methane production, reduction of total and volatile solids and hydrolysis rate constant. Most of the wastes had a methane yield of 0.24–0.28 m³CH4(STP)/kg VSinitial and 76–89% of the theoretical methane yield was achieved. Reduction of 50–73% in total solids and 75...

  1. ANAEROBIC CO-DIGESTION OF WASTED VEGETABLES AND ACTIVATED SLUDGE

    OpenAIRE

    Saev, M.; Koumanova, B.; Ivan, Simeonov

    2009-01-01

    Anaerobic co-digestion of activated sludge (AS) and wasted vegetables (wasted cucumbers (WC) and wasted tomatoes (WT)) was carried out at mesophilic conditions (34 ± 0.5 0C). A continuously stirred bioreactor with volume of 5 dm3 (3 dm3 working volume) was used. The digestion was examined in semi-continuous mode and 30 days hydraulic retention time. Total solids, volatile solids, COD and volatile fatty acids (VFA) were determined according to the standard methods. Daily the total biogas produ...

  2. Waste form development for use with ORNL waste treatment facility sludge

    International Nuclear Information System (INIS)

    A sludge that simulates Water Softening Sludge number 5 (WSS number 5 filtercake) at Oak Ridge National Laboratory was prepared and evaluated for its thermal behavior, volume reduction, stabilization, surface area and compressive strength properties. Compaction of the surrogate waste and the calcium oxide (produced by calcination) in the presence of paraffin resulted in cylindrical molds with various degrees of stability. This work has demonstrated that surrogate WSS number 5 at ORNL can be successfully stabilized by blending it with about 35 percent paraffin and compacting the mixture at 8000 psi. This compressive strength of the waste form is sufficient for temporary storage of the waste while long-term storage waste forms are developed. Considering the remarkable similarity between the surrogate and the actual filtercake, the findings of this project should be useful for treating the sludge generated by the waste treatment facility at ORNL

  3. CFD analysis of sludge accumulation and hydraulic performance of a waste stabilization pond.

    Science.gov (United States)

    Alvarado, Andres; Sanchez, Esteban; Durazno, Galo; Vesvikar, Mehul; Nopens, Ingmar

    2012-01-01

    Sludge management in waste stabilization ponds (WSPs) is essential for safeguarding the system performance. Sludge accumulation patterns in WSPs are strongly influenced by the pond hydrodynamics. CFD modeling was applied to study the relation between velocity profiles and sludge deposition during 10 years of operation of the Ucubamba WSP in Cuenca (Ecuador). One tracer experiment was performed and three sludge accumulation scenarios based on bathymetric surveys were simulated. A residence time distribution (RTD) analysis illustrated the decrease of residence times due to sludge deposition. Sludge accumulation rates were calculated. The influence of flow pattern on the sludge deposition was studied, enabling better planning of future pond operation and desludging. PMID:23032767

  4. Tank 42 sludge-only process development for the Defense Waste Processing Facility (DWPF)

    International Nuclear Information System (INIS)

    Defense Waste Processing Facility (DWPF) requested the development of a sludge-only process for Tank 42 sludge since at the current processing rate, the Tank 51 sludge has been projected to be depleted as early as August 1998. Testing was completed using a non-radioactive Tank 42 sludge simulant. The testing was completed under a range of operating conditions, including worst case conditions, to develop the processing conditions for radioactive Tank 42 sludge. The existing Tank 51 sludge-only process is adequate with the exception that 10 percent additional acid is recommended during sludge receipt and adjustment tank (SRAT) processing to ensure adequate destruction of nitrite during the SRAT cycle

  5. Tank 42 sludge-only process development for the Defense Waste Processing Facility (DWPF)

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, D.P.

    2000-03-22

    Defense Waste Processing Facility (DWPF) requested the development of a sludge-only process for Tank 42 sludge since at the current processing rate, the Tank 51 sludge has been projected to be depleted as early as August 1998. Testing was completed using a non-radioactive Tank 42 sludge simulant. The testing was completed under a range of operating conditions, including worst case conditions, to develop the processing conditions for radioactive Tank 42 sludge. The existing Tank 51 sludge-only process is adequate with the exception that 10 percent additional acid is recommended during sludge receipt and adjustment tank (SRAT) processing to ensure adequate destruction of nitrite during the SRAT cycle.

  6. Vermicomposting of milk processing industry sludge spiked with plant wastes.

    Science.gov (United States)

    Suthar, Surindra; Mutiyar, Pravin K; Singh, Sushma

    2012-07-01

    This work illustrates the vermistabilization of wastewater sludge from a milk processing industry (MPIS) unit spiked with cow dung (CD), sugarcane trash (ST) and wheat straw (WS) employing earthworms Eisenia fetida. A total of nine experimental vermibeds were established and changes in chemical parameters of waste material have been observed for 90 days. Vermistabilization caused significant reduction in pH, organic carbon and C:N ratio and substantial increase in total N, available P and exchangeable K. The waste mixture containing MPIS (60%)+CD (10%)+ST (30%) and MPIS (60%)+CD (10%)+WS (30%) had better waste mineralization rate among waste mixtures studied. The earthworm showed better biomass and cocoon numbers in all vermibeds during vermicomposting operation. Results, thus suggest the suitability of E. fetida for conversion of noxious industrial waste into value-added product for land restoration programme. PMID:22609678

  7. Alkali washing of simulated radioactive waste sludge

    International Nuclear Information System (INIS)

    The large volume of radioactive waste generated from uranium and plutonium recovery processes is currently stored in underground tanks at various U.S. Department of Energy sites. This waste is mainly in the form of metal oxides or precipitated metal hydroxides and the bulk of this material is nonradioactive. In order to remove this larger, nonradioactive component, methods are being developed to pretreat this waste by taking advantage of the solubility of aluminum and other nonradioactive elements under caustic conditions. A synthetic waste containing uranium and thorium was prepared based on published information. The solubility of ten elements was measured as a function of NaOH concentration, temperature, and time. The effects of aging the waste for five days at 100 degrees C in pH 10 solution were also studied. The results of the studies on uranium and thorium containing waste were similar to previous investigations, with significant amounts of aluminum, zinc, and chromium being removed by 6 M NaOH. The aging process decreased the amount of aluminum removed, while the amount of chromium removed was increased using the same caustic washing conditions. At 70 degrees C, both the rate and amount of the elements removed increased, with aluminum being effected the most. The usefulness of caustic dissolution as a possible pretreatment method to remove nonradioactive elements from the radioactive waste will be discussed

  8. Composting sewage sludge with green waste from tree pruning

    OpenAIRE

    Sarah Mello Leite Moretti; Edna Ivani Bertoncini; Cassio Hamilton Abreu-Junior

    2015-01-01

    Sewage sludge (SS) has been widely used as organic fertilizer. However, its continuous use can cause imbalances in soil fertility as well as soil-water-plant system contamination. The study aimed to evaluate possible improvements in the chemical and microbiological characteristics of domestic SS, with low heavy metal contents and pathogens, through the composting process. Two composting piles were set up, based on an initial C/N ratio of 30:1, with successive layers of tree pruning waste and ...

  9. Valorization and inertization of galvanic sludge waste in clay bricks

    OpenAIRE

    Pérez-Villarejo, L.; Martínez-Martínez, S; Carrasco-Hurtado, B.; Eliche-Quesada, D.; Ureña-Nieto, C.; Sánchez-Soto, Pedro José

    2015-01-01

    Galvanic sludge wastes (GSW) are produced by the physico-chemical treatments of wastewater generated by electroplating plants. These materials have a significant potential for the production of clay ceramic bricks. This paper focuses on the viability of the inertization of heavy metals from GSW mixed with clays. The original materials were obtained by mixing three types of raw clay (red, yellow and black) in equal parts with GSW. These mixtures were characterized by XRD, XRF, and chemical ele...

  10. Possible uses of sewage sludge from the urban waste water treatment plant Murska Sobota

    OpenAIRE

    Bernjak, Andreja

    2013-01-01

    This diploma thesis examines the current situation of sewage sludge management at the waste-water treatment plant in Murska Sobota. The export of sewage sludge to neighbour countries was found to be an unsuitable solution at the given knowledge in this field. Sewage sludge from the municipal waste-water treatment plant in Murska Sobota is not waste but has energetic potential, among others. Analyses were performed, following procedures which are regulated by the current legislation. These ana...

  11. Correlation models for waste tank sludges and slurries

    International Nuclear Information System (INIS)

    This report presents the results of work conducted to support the TEMPEST computer modeling under the Flammable Gas Program (FGP) and to further the comprehension of the physical processes occurring in the Hanford waste tanks. The end products of this task are correlation models (sets of algorithms) that can be added to the TEMPEST computer code to improve the reliability of its simulation of the physical processes that occur in Hanford tanks. The correlation models can be used to augment, not only the TEMPEST code, but other computer codes that can simulate sludge motion and flammable gas retention. This report presents the correlation models, also termed submodels, that have been developed to date. The submodel-development process is an ongoing effort designed to increase our understanding of sludge behavior and improve our ability to realistically simulate the sludge fluid characteristics that have an impact on safety analysis. The effort has employed both literature searches and data correlation to provide an encyclopedia of tank waste properties in forms that are relatively easy to use in modeling waste behavior. These properties submodels will be used in other tasks to simulate waste behavior in the tanks. Density, viscosity, yield strength, surface tension, heat capacity, thermal conductivity, salt solubility, and ammonia and water vapor pressures were compiled for solutions and suspensions of sodium nitrate and other salts (where data were available), and the data were correlated by linear regression. In addition, data for simulated Hanford waste tank supernatant were correlated to provide density, solubility, surface tension, and vapor pressure submodels for multi-component solutions containing sodium hydroxide, sodium nitrate, sodium nitrite, and sodium aluminate

  12. Correlation models for waste tank sludges and slurries

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, L.A.; Trent, D.S.

    1995-07-01

    This report presents the results of work conducted to support the TEMPEST computer modeling under the Flammable Gas Program (FGP) and to further the comprehension of the physical processes occurring in the Hanford waste tanks. The end products of this task are correlation models (sets of algorithms) that can be added to the TEMPEST computer code to improve the reliability of its simulation of the physical processes that occur in Hanford tanks. The correlation models can be used to augment, not only the TEMPEST code, but other computer codes that can simulate sludge motion and flammable gas retention. This report presents the correlation models, also termed submodels, that have been developed to date. The submodel-development process is an ongoing effort designed to increase our understanding of sludge behavior and improve our ability to realistically simulate the sludge fluid characteristics that have an impact on safety analysis. The effort has employed both literature searches and data correlation to provide an encyclopedia of tank waste properties in forms that are relatively easy to use in modeling waste behavior. These properties submodels will be used in other tasks to simulate waste behavior in the tanks. Density, viscosity, yield strength, surface tension, heat capacity, thermal conductivity, salt solubility, and ammonia and water vapor pressures were compiled for solutions and suspensions of sodium nitrate and other salts (where data were available), and the data were correlated by linear regression. In addition, data for simulated Hanford waste tank supernatant were correlated to provide density, solubility, surface tension, and vapor pressure submodels for multi-component solutions containing sodium hydroxide, sodium nitrate, sodium nitrite, and sodium aluminate.

  13. Recycling of radioactive oil sludge waste into pavement brick

    International Nuclear Information System (INIS)

    Malaysia produces about 1450 tons of radioactive oil sludge waste per year and there is an urgent need to find a permanent solution to the storage and disposal of this radioactive waste problem. Several treatment methods such bacteria farming, ultracentrifuge, steam reforming and incineration are currently being used but the core issue of the radioactive material in the oil sludge had not been solved. The paper relates a study on utilizing the radioactive component of the oil sludge and turning them into pavement brick. Characteristic study of this radioactive component by XRD and XRF show that it mainly comprised of quartz and anorthite minerals. While the radioactivity analysis by gamma technique shows that more than 90 % of this radioactivity comes from this soil component with Ra-226 and Ra-228 as the main radionuclides. A vitrified brick was then produced from this sediment by mixing it with low radioactive local red clay. The result also shows that the formation of the vitrified layer may be due high content of K in the red clay. Tensile test on the brick shows that it has more than four times the strength of commercial clay brick. Long duration leaching test on the brick also shows that there is no dissolution of radionuclide from the brick. (author)

  14. Laboratory stabilization/solidification of surrogate and actual mixed-waste sludge in glass and grout

    International Nuclear Information System (INIS)

    Grouting and vitrification are currently the most likely stabilization/solidification technologies for mixed wastes. Grouting has been used to stabilize and solidify hazardous and low-level waste for decades. Vitrification has long been developed as a high-level-waste alternative and has been under development recently as an alternative treatment technology for low-level mixed waste. Laboratory testing has been performed to develop grout and vitrification formulas for mixed-waste sludges currently stored in underground tanks at Oak Ridge National Laboratory (ORNL) and to compare these waste forms. Envelopes, or operating windows, for both grout and soda-lime-silica glass formulations for a surrogate sludge were developed. One formulation within each envelope was selected for testing the sensitivity of performance to variations (±10 wt%) in the waste form composition and variations in the surrogate sludge composition over the range previously characterized in the sludges. In addition, one sludge sample of an actual mixed-waste tank was obtained, a surrogate was developed for this sludge sample, and grout and glass samples were prepared and tested in the laboratory using both surrogate and the actual sludge. The sensitivity testing of a surrogate tank sludge in selected glass and grout formulations is discussed in this paper, along with the hot-cell testing of an actual tank sludge sample

  15. Sewage Sludge Treatment for Energy Purpose in China : Waste Treatment in China

    OpenAIRE

    Nyyssönen, Ville

    2015-01-01

    This thesis is made for ANDRITZ China Technology to find out sludge incineration potential in China. ANDRITZ is looking for markets and customers for ANDRITZ sewage sludge incineration technology in China. In addition ANDRITZ China manufactures centrifuges, skeleton model filter presses, belt presses and rotatory drums to treat the sludge. Sludge in China has become a major problem. It is considered to be toxic waste, because it contains pathogens, which are dangerous for human health. Th...

  16. Microwave-assisted chemical oxidation of biological waste sludge: simultaneous micropollutant degradation and sludge solubilization.

    Science.gov (United States)

    Bilgin Oncu, Nalan; Akmehmet Balcioglu, Isil

    2013-10-01

    Microwave-assisted hydrogen peroxide (MW/H2O2) treatment and microwave-assisted persulfate (MW/S2O8(2-)) treatment of biological waste sludge were compared in terms of simultaneous antibiotic degradation and sludge solubilization. A 2(3) full factorial design was utilized to evaluate the influences of temperature, oxidant dose, and holding time on the efficiency of these processes. Although both MW/H2O2 and MW/S2O8(2-) yielded ≥97% antibiotic degradation with 1.2g H2O2 and 0.87 g S2O8(2-) per gram total solids, respectively, at 160 °C in 15 min, MW/S2O8(2-) was found to be more promising for efficient sludge treatment at a lower temperature and a lower oxidant dosage, as it allows more effective activation of persulfate to produce the SO4(-) radical. Relative to MW/H2O2, MW/S2O8(2-) gives 48% more overall metal solubilization, twofold higher improvement in dewaterability, and the oxidation of solubilized ammonia to nitrate in a shorter treatment period. PMID:23928124

  17. Effects of waste glass additions on quality of textile sludge-based bricks.

    Science.gov (United States)

    Rahman, Ari; Urabe, Takeo; Kishimoto, Naoyuki; Mizuhara, Shinji

    2015-01-01

    This research investigated the utilization of textile sludge as a substitute for clay in brick production. The addition of textile sludge to a brick specimen enhanced its pores, thus reducing the quality of the product. However, the addition of waste glass to brick production materials improved the quality of the brick in terms of both compressive strength and water absorption. Maximum compressive strength was observed with the following composition of waste materials: 30% textile sludge, 60% clay and 10% waste glass. The melting of waste glass clogged up pores on the brick, which improved water absorption performance and compressive strength. Moreover, a leaching test on a sludge-based brick to which 10% waste glass did not detect significant heavy metal compounds in leachates, with the product being in conformance with standard regulations. The recycling of textile sludge for brick production, when combined with waste glass additions, may thus be promising in terms of both product quality and environmental aspects. PMID:25812619

  18. Gas Retention and Release from Hanford Site Sludge Waste Tanks

    Energy Technology Data Exchange (ETDEWEB)

    Meacham, Joseph E.; Follett, Jordan R.; Gauglitz, Phillip A.; Wells, Beric E.; Schonewill, Philip P.

    2015-02-18

    Radioactive wastes from nuclear fuel processing are stored in large underground storage tanks at the Hanford Site. Solid wastes can be divided into saltcake (mostly precipitated soluble sodium nitrate and nitrite salts with some interstitial liquid consisting of concentrated salt solutions) and sludge (mostly low solubility aluminum and iron compounds with relatively dilute interstitial liquid). Waste generates hydrogen through the radiolysis of water and organic compounds, radio-thermolytic decomposition of organic compounds, and corrosion of a tank’s carbon steel walls. Nonflammable gases, such as nitrous oxide and nitrogen, are also produced. Additional flammable gases (e.g., ammonia and methane) are generated by chemical reactions between various degradation products of organic chemicals present in the tanks.

  19. Hazardous Waste Code Determination for First/Second-Stage Sludge Waste Stream (IDCs 001, 002, 800)

    International Nuclear Information System (INIS)

    This document, Hazardous Waste Code Determination for the First/Second-Stage Sludge Waste Stream, summarizes the efforts performed at the Idaho National Engineering and Environmental Laboratory (INEEL) to make a hazardous waste code determination on Item Description Codes (IDCs) 001, 002, and 800 drums. This characterization effort included a thorough review of acceptable knowledge (AK), physical characterization, waste form sampling, chemical analyses, and headspace gas data. This effort included an assessment of pre-Waste Analysis Plan (WAP) solidified sampling and analysis data (referred to as preliminary data). Seventy-five First/Second-Stage Sludge Drums, provided in Table 1-1, have been subjected to core sampling and analysis using the requirements defined in the Quality Assurance Program Plan (QAPP). Based on WAP defined statistical reduction, of preliminary data, a sample size of five was calculated. That is, five additional drums should be core sampled and analyzed. A total of seven drums were sampled, analyzed, and validated in compliance with the WAP criteria. The pre-WAP data (taken under the QAPP) correlated very well with the WAP compliant drum data. As a result, no additional sampling is required. Based upon the information summarized in this document, an accurate hazardous waste determination has been made for the First/Second-Stage Sludge Waste Stream

  20. Hazardous Waste Code Determination for First/Second-Stage Sludge Waste Stream (IDCs 001, 002, 800)

    Energy Technology Data Exchange (ETDEWEB)

    Arbon, R.E.

    2001-01-31

    This document, Hazardous Waste Code Determination for the First/Second-Stage Sludge Waste Stream, summarizes the efforts performed at the Idaho National Engineering and Environmental Laboratory (INEEL) to make a hazardous waste code determination on Item Description Codes (IDCs) 001, 002, and 800 drums. This characterization effort included a thorough review of acceptable knowledge (AK), physical characterization, waste form sampling, chemical analyses, and headspace gas data. This effort included an assessment of pre-Waste Analysis Plan (WAP) solidified sampling and analysis data (referred to as preliminary data). Seventy-five First/Second-Stage Sludge Drums, provided in Table 1-1, have been subjected to core sampling and analysis using the requirements defined in the Quality Assurance Program Plan (QAPP). Based on WAP defined statistical reduction, of preliminary data, a sample size of five was calculated. That is, five additional drums should be core sampled and analyzed. A total of seven drums were sampled, analyzed, and validated in compliance with the WAP criteria. The pre-WAP data (taken under the QAPP) correlated very well with the WAP compliant drum data. As a result, no additional sampling is required. Based upon the information summarized in this document, an accurate hazardous waste determination has been made for the First/Second-Stage Sludge Waste Stream.

  1. REAL WASTE TESTING OF SLUDGE BATCH 5 MELTER FEED RHEOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, S.; Stone, M.

    2010-03-17

    Clogging of the melter feed loop at the Defense Waste Processing Facility (DWPF) has reduced the throughput of Sludge Batch 5 (SB5) processing. After completing a data review, DWPF attributed the clogging to the rheological properties of the Slurry Mix Evaporator (SME) project. The yield stress of the SB5 melter feed material was expected to be high, based on the relatively high pH of the SME product and the rheological results of a previous Chemical Process Cell (CPC) demonstration performed at the Savannah River National Laboratory (SRNL).

  2. Treatment of Lagoon sludge waste generated from Uranium Conversion Plant

    International Nuclear Information System (INIS)

    This study investigated the dissolution property of nitrate salts in the desalination process by water and the drying property of residual solid after separating nitrates in a series of processes for the sludge treatment. Desalination was carried out with the adding ratio of water and drying property was analyzed by TG/DTA, FTIR, and XRD. Nitrate salts involved in the sludge were separated over 97 % at the water adding ratio of 2.5. But a small quantity of calcium and sodium nitrate remained in the residue. These were decomposed over 600 deg. C while calcium carbonate, which was a main compound of residual solid, was decomposed into calcium oxide over 750 deg. C. The residual solid has to be decomposed over 800 deg. C to converse uranyl nitrate of six values into the stable U3O8 of four values. As a result of removing the nitrates at the adding ratio of 2.5 and drying the residue over 900 deg. C, volume of the sludge waste decreased over 80 %. (authors)

  3. Ferrocyanide Safety Program: Waste tank sludge rheology within a hot spot or during draining

    International Nuclear Information System (INIS)

    The conditions under which ferrocyanide waste sludge flows as a homogeneous non-Newtonian two-phase (solid precipitate-liquid) mixture rather than as a liquid through a porous medium (of stationary precipitate) are examined theoretically, based on the notion that the preferred rheological behavior of the sludge is the one which imposes the least resistance to the sludge flow. The homogeneous two-phase mixture is modeled as a power-law fluid and simple criteria are derived that show that the homogeneous power-law sludge-flow is a much more likely flow situation than the porous medium model of sludge flow. The implication of this finding is that the formation of a hot spot or the drainage of sludge from a waste tank are not likely to result in the uncovering (drying) and subsequent potential overheating of the reactive-solid component of the sludge

  4. Effect of ultrasound, low-temperature thermal and alkali treatments on physicochemical and biological properties of waste activated sludge

    OpenAIRE

    Ruiz Hernando, María

    2015-01-01

    [eng] The development of treatment processes to reduce or reuse sewage sludge is crucial for a proper environmental management. Segregating primary from secondary sludge allows for better reuse of secondary sludge, since digested secondary sludge is better suited for agricultural application, containing about double concentration in nutrients but significantly less contaminants. However, secondary sludge (also called waste activated sludge (WAS)) is difficult to dewater compared with primary...

  5. Waste Sludge Characteristics of a Wastewater Treatment Plant Compared with Environmental Standards

    Directory of Open Access Journals (Sweden)

    AR Mesdaghinia

    2004-06-01

    Full Text Available Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. On the other hand, this sludge has benefits for plants and soils. Thereupon, land application of sludge has received much attention over the traditional incineration and dump in sea. The comprehensive regulations of U.S.EPA title 40 CFR parts 503 include criteria and standards for land application of sludge. One of the most important wastewater treatment plants in Tehran, Iran is Shoosh Plant, which applies its waste sludge in agricultural lands after dewatering in drying beds. In this research, waste sludge from drying beds was examined according to 40 CFR parts 503. Results indicate that the dehydrated sludge has not the characteristics required for final discharge. If the dewatering process in the existing beds of the plant would be modified according to title 40 CFR part 503, the standard of Pathogen Reduction class B would be achieved. Waste sludge of drying bed must be applied in agricultural land with respect to the conditions of application method that is presented in vector attraction reduction. Concentration of this waste sludge is less than ceiling concentration limits identified by title 40 CFR parts 503.

  6. Characterization, Leaching, and Filtrations Testing of Ferrocyanide Tank sludge (Group 8) Actual Waste Composite

    Energy Technology Data Exchange (ETDEWEB)

    Fiskum, Sandra K.; Billing, Justin M.; Crum, J. V.; Daniel, Richard C.; Edwards, Matthew K.; Shimskey, Rick W.; Peterson, Reid A.; MacFarlan, Paul J.; Buck, Edgar C.; Draper, Kathryn E.; Kozelisky, Anne E.

    2009-02-28

    This is the final report in a series of eight reports defining characterization, leach, and filtration testing of a wide variety of Hanford tank waste sludges. The information generated from this series is intended to supplement the Waste Treatment and Immobilization Plant (WTP) project understanding of actual waste behaviors associated with tank waste sludge processing through the pretreatment portion of the WTP. The work described in this report presents information on a high-iron waste form, specifically the ferrocyanide tank waste sludge. Iron hydroxide has been shown to pose technical challenges during filtration processing; the ferrocyanide tank waste sludge represented a good source of the high-iron matrix to test the filtration processing.

  7. Gamma irradiation induced disintegration of waste activated sludge for biological hydrogen production

    Science.gov (United States)

    Yin, Yanan; Wang, Jianlong

    2016-04-01

    In this paper, gamma irradiation was applied for the disintegration and dissolution of waste activated sludge produced during the biological wastewater treatment, and the solubilized sludge was used as substrate for bio-hydrogen production. The experimental results showed that the solubilization of waste activated sludge was 53.7% at 20 kGy and pH=12, and the SCOD, polysaccharides, protein, TN and TP contents in the irradiated sludge solutions was 3789.6 mg/L, 268.3 mg/L, 1881.5 mg/L, 132.3 mg/L and 80.4 mg/L, respectively. The irradiated sludge was used for fermentative hydrogen production, and the hydrogen yield was 10.5±0.7 mL/g SCODconsumed. It can be concluded that the irradiated waste activated sludge could be used as a low-cost substrate for fermentative hydrogen production.

  8. Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges

    International Nuclear Information System (INIS)

    Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material was more pronounced under aerobic metabolic conditions than under strict anaerobic conditions. The changes in the hydrocarbon molecular weight distribution, infrared spectra, and PAH concentrations during slurry-phase treatment indicate that the aerobic thermophilic bioslurry achieved a higher degree of hydrocarbon degradation than the anaerobic thermophilic bioslurry during the same time period

  9. Characterization of Radionuclides in Purex Waste Sludges from the F-Area High Level Waste Tanks (U)

    Energy Technology Data Exchange (ETDEWEB)

    Obryant, R

    2005-06-13

    Sludge-contaminated waste consists of waste contaminated with both insoluble species (the sludge fraction) and entrained supernate. The WCS is based on the assumption that approximately 70% of the weight of what is commonly referred to as sludge is interstitial supernate; the remaining approximately 30% consists of the insoluble species (Reference 1). Development of a method for characterization of sludge-contaminated waste must consider both fractions. Separate waste cuts may contain sludge and supernate fractions in varying proportions due to the nature of the job generating the waste and the variability in waste handling techniques. Development of a distribution representative of all sludge-contaminated waste cuts must allow for varying fractions of sludge and supernate contamination. This document will develop a radionuclide distribution in accordance with the methodology outlined in WSRC 1S SRS Waste Acceptance Criteria Manual, Procedure 2.02, Revision 8 for the sludge fraction of sludge-contaminated waste generated in the F-Area Tank Farm This distribution was based on the assumption that sludge-contaminated waste from F-Area Tank Farm Waste Tanks could be co-mingled, and the actual contamination present on waste in a series of containers from these tanks will be representative of the mean radionuclide distribution. The original characterization was based primarily on process knowledge and fill histories (Reference 6). A single, comprehensive characterization for supernate has been developed previously (Reference 9). This document also describes the methodology for application of radionuclide distributions representative of the sludge and supernate fractions of sludge-contaminated waste to individual waste packages. Most of the waste contaminated with sludge from the F-Area Tank Farm will be categorized as Low Level Waste (LLW) and disposed of in the E-area trenches. The waste does, however, have the potential to be categorized as TRU and/or mixed waste

  10. Management of waste cladding hulls. Part II. An assessment of zirconium pyrophoricity and recommendations for handling waste hulls

    Energy Technology Data Exchange (ETDEWEB)

    Kullen, B J; Levitz, N M; Steindler, M J

    1977-11-01

    This report reviews experience and research related to the pyrophoricity of zirconium and zirconium alloys. The results of recent investigations of the behavior of Zircaloy and some observations of industrial handling and treatment of Zircaloy tubing and scrap are also discussed. A model for the management of waste Zircaloy cladding hulls from light water reactor fuel reprocessing is offered, based on an evaluation of the reviewed information. It is concluded that waste Zircaloy cladding hulls do not constitute a pyrophoric hazard if, following the model flow sheet, finely divided metal is oxidized during the management procedure. Steps alternative to the model are described which yield zirconium in deactivated form and also accomplish varying degrees of transuranic decontamination. Information collected into appendixes is (1) a collation of zirconium pyrophoricity data from the literature, (2) calculated radioactivity contents in Zircaloy cladding hulls from spent LWR fuels, and (3) results of a laboratory study on volatilization of zirconium from Zircaloy using HCl or Cl/sub 2/.

  11. Technology for removing sludge and cleaning Savannah River Plant radioactive liquid waste tanks

    International Nuclear Information System (INIS)

    A new two-step process has been developed for removing sludge and cleaning Savannah River Plant waste tanks scheduled for retirement. Step 1 is a low-pressure, hydraulic-slurrying technique that uses a minimum amount of power to recirculate liquid waste and to suspend sludges. Step 2 is a chemical technique for dissolving unsuspended residue with oxalic acid, and includes water rinses and continued hydraulic slurrying. Full-scale demonstrations of the hydraulic slurrying steps in a waste tank mockup (with kaolin clay as a stand-in for waste sludges) confirmed theoretical predictions that the effective cleaning radius was directly proportional to the momentum of the jet. Small-scale dissolving tests with actual sludges showed that over 95 percent of the sludge could be dissolved in oxalic acid solutions. 24 figures

  12. Proceedings of the workshop on radioactive, hazardous, and/or mixed waste sludge management

    International Nuclear Information System (INIS)

    A workshop sponsored by the US Department of Energy (DOE) Field Office, Oak Ridge, was held on December 4--6, 1990, in Knoxville, Tennessee. The primary objective of the workshop was the exchange of information, experiences, solutions, and future plans of DOE and its prime contractors who are engaged in work on the packaging, grouting, storage, and transport of waste sludges. In addition, the group met with industrial participants in an open forum to discuss problems and needs in the management of these wastes and to learn of possible industrial experiences, approaches, and solutions, including demonstrations of potential tools and techniques. Topics discussed include the following: mixed waste sludge issue at the K-25 site; processing saltstone from waste streams at the Savannah River Plant; the Hanford Grout Treatment Facility; treatment of pond sludge at the Rocky Flats Plant; cement solidification of low-level radioactive sludge at the West Valley Demonstration Project; studies on the solidification of low-level radioactive wastes in cement at INEL; cement solidification systems at Los Alamos National Laboratory; emergency avoidance solidification campaign at ORNL; diffusion plant sludge storage problems at the Portsmouth Gaseous Diffusion Plant; the proposed fixation of sludge in cement at the feed materials production center; regulatory aspects of sludge management; and delisting efforts for K-1407-C pond sludges. Individual projects are processed separately for the data bases

  13. Development of Rotary Magnetoferrite Treatment with Stirrers for Waste Water Treatment Plants to Reduce Excess Sludge

    OpenAIRE

    Mahmudul Kabir; Masafumi Suzuki; Noboru Yoshimura

    2012-01-01

    A large amount of excess sludge is being produced in the waste water treatment plants (WWTPs), which is a serious problem in terms of economical and environmental problems. So, the experiments on reduction of excess sludge are carried out. We have introduced a new approach for reduction of excess sludge by using ferrite particles and permanent magnets. A rotary treatment plant was introduced which showed good possibilities of this method for application in the WWTPs. Stirrers hold a very impo...

  14. Codigestion of olive oil mill wastewaters with manure, household waste or sewage sludge

    DEFF Research Database (Denmark)

    Angelidaki, I.; Ahring, B.K.

    1997-01-01

    Combined anaerobic digestion of oil mill effluent (OME) together with manure, household waste (HHW) or sewage sludge was investigated. In batch experiments it was shown that OME could be degraded into biogas when codigested with manure. In codigestion with HHW or sewage sludge, OME dilution with...

  15. Sewage sludge drying process integration with a waste-to-energy power plant.

    Science.gov (United States)

    Bianchini, A; Bonfiglioli, L; Pellegrini, M; Saccani, C

    2015-08-01

    Dewatered sewage sludge from Waste Water Treatment Plants (WWTPs) is encountering increasing problems associated with its disposal. Several solutions have been proposed in the last years regarding energy and materials recovery from sewage sludge. Current technological solutions have relevant limits as dewatered sewage sludge is characterized by a high water content (70-75% by weight), even if mechanically treated. A Refuse Derived Fuel (RDF) with good thermal characteristics in terms of Lower Heating Value (LHV) can be obtained if dewatered sludge is further processed, for example by a thermal drying stage. Sewage sludge thermal drying is not sustainable if the power is fed by primary energy sources, but can be appealing if waste heat, recovered from other processes, is used. A suitable integration can be realized between a WWTP and a waste-to-energy (WTE) power plant through the recovery of WTE waste heat as energy source for sewage sludge drying. In this paper, the properties of sewage sludge from three different WWTPs are studied. On the basis of the results obtained, a facility for the integration of sewage sludge drying within a WTE power plant is developed. Furthermore, energy and mass balances are set up in order to evaluate the benefits brought by the described integration. PMID:25959614

  16. Effects of total solids content on waste activated sludge thermophilic anaerobic digestion and its sludge dewaterability.

    Science.gov (United States)

    Wang, Tianfeng; Chen, Jie; Shen, Honglang; An, Dong

    2016-10-01

    The role of total solids content on sludge thermophilic anaerobic digestion was investigated in batch reactors. A range of total solids content from 2% to 10% was evaluated with two replicates. The lowest inhibitory concentration for free ammonia and total ammonia of sludge thermophilic anaerobic digestion was 110.9-171.4mg/L and 1313.1-1806.7mg/L, respectively. The volumetric biogas production rate increased with increasing of total solids content, but the corresponding biogas yield per gram volatile solid decreased. The result of normalized capillary suction time indicated that the dewaterability of digested sludge at high total solids content was poor, while solid content of sediment obtained by centrifuging sludge at 2000g for 10min increased with increasing of total solids content of sludge. The results suggest that thickened sludge mixed with dewatered sludge at an appropriate ratio could get high organic loading rate, high biogas yield and adequate dewatering effort. PMID:26897469

  17. Hazard Evaluation for Storage of Spent Nuclear Fuel (SNF) Sludge at the Solid Waste Treatment Facility

    International Nuclear Information System (INIS)

    The Solid Waste Treatment Facility, referred to throughout this document as T Plant, has been identified as the location where sludge from the K Basin fuel storage facilities will be stored until final disposition of the material occurs

  18. Effective Utilization of Waste Activated Sludge For Bioremediation and Bioenergy Production

    OpenAIRE

    Nazlina Haiza Mohd Yasin

    2015-01-01

    Activated sludge system is widely used in treating wastewater. However, this system creates a lot of waste activated sludge (WAS). The abundance of WAS creates serious problem to municipalities and industries in term of treatment cost and waste management. Hence, the purpose of my Ph. D. study is to seek an appropriate means for WAS management. Here, four approaches for utilizing WAS effectively are investigated; 1) WAS reduction at low temperature by using low temperature tolerant bacteria, ...

  19. Improvement of anaerobic bio-hydrogen gas production from organic sludge waste

    International Nuclear Information System (INIS)

    Microbial hydrogen gas production from organic matters stands out as one of the most promising alternatives for sustainable green energy production. Based on the literature review, investigation of anaerobic bio-hydrogen gas production from organic sludge waste using a mixed culture has been very limited. The objective of this study was to assess the anaerobic bio-hydrogen gas production from organic sludge waste under various conditions. (Author)

  20. A study on the dewatering of industrial waste sludge by fry-drying technology

    International Nuclear Information System (INIS)

    In sludge treatment, drying sludge using typical technology with high water content to a water content of approximately 10% is always difficult because of adhesive characteristics of sludge. Many methods have been applied, including direct and indirect heat drying, but these approaches of reducing water content to below 40% after drying is very inefficient in energy utilization of drying sludge. In this study, fry-drying technology with a high heat transfer coefficient of approximately 500 W/m2 deg. C was used to dry industrial wastewater sludge. Also waste oil was used in the fry-drying process, and because the oil's boiling point is between 240 and 340 deg. C and the specific heat is approximately 60% of that of water. In the fry-drying system, the sludge is input by molding it into a designated form after heating the waste oil at temperatures between 120 and 170 deg. C. At these temperatures, the heated oil rapidly evaporates the water contained in the sludge, leaving the oil itself. After approximately 10 min, the water content of the sludge was less than 10%, and its heating value surpassed 5300 kcal/kg. Indeed, this makes the organic sludge appropriate for use as a solid fuel. The wastewater sludge used in this study was the designated waste discharged from chemical, leather and plating plants. These samples varied in characteristics, especially with regard to heavy metal concentration. After drying the three kinds of wastewater sludge at oil temperatures 160 deg. C for 10 min, it was found that the water content in the sludge from the chemical, leather, and plating plants reduced from 80.0 to 5.5%, 81.6 to 1.0%, and 65.4 to 0.8%, respectively. Furthermore, the heat values of the sludge from the chemical, leather, and plating plants prior to fry-drying were 217, 264, and 428 kcal/kg, respectively. After drying, these values of sludge increased to 5317, 5983 and 6031 kcal/kg, respectively. The heavy metals detected in the sludge after drying were aluminum

  1. Bioleaching of zinc and aluminium from industrial waste sludges by means of Thiobacillus ferrooxidans.

    Science.gov (United States)

    Solisio, C; Lodi, A; Veglio, F

    2002-01-01

    Biological solubilisation of heavy metals contained in two different kinds of industrial wastes was performed in batches employing a strain of Thiobacillus ferroxidans. The wastes tested were: a dust coming from the iron-manganese alloy production in an electric furnace (sludge 1) and a sludge coming from a process treatment plant of aluminium anodic oxidation (sludge 2). The experimental results pointed out the ability of the used strain to maintain the environment, that initially has a pH about 8, at strongly acid conditions (pH 2.5-3.5), producing sulphuric acid that is the chemical agent responsible for the metals solubilisation. At wastes initial concentration of 1%, the percentage of solubilised metals was 76 and 78% for the wastes 1 and 2, respectively, but the lag phase was considerably longer for sludge 2 than for sludge 1, indicating a different affinity of microorganisms for the solid phase. Increasing the initial slurry concentration, the percentage of removed metal reached 72-73% for the sludge 1, while in case of sludge 2, the total amount of solubilized metal progressively decreased. Two kinetic models are proposed to describe the trends of metals solubilization curves. PMID:12214978

  2. Characterization of actinides in simulated alkaline tank waste sludges and leach solutions

    International Nuclear Information System (INIS)

    Current plans call for an alkaline scrub of actinide-bearing sludges in the Hanford Waste tanks prior to their incorporation in glass waste forms. Though it is assumed that actinides will remain in the sludge phase during this procedure, this assumption is based on insufficient supporting thermodynamic and kinetic data. In this project the authors will investigate the fundamental chemistry of actinides in strongly alkaline solution and solid phases to strengthen the foundation and identify potential limitations of this approach. They will focus on the characterization of the leaching of actinides from simulated BiPO4, REDOX, and PUREX sludges, the identification of actinide mineral phases in the sludge simulants, and the possible solubilization of actinides by complexation and radiolysis effects. This program will provide new fundamental information on the chemical behavior and speciation of uranium, neptunium, plutonium, and americium in simulated alkaline tank waste sludges and alkaline scrub liquors. Sludge simulants will be prepared from the appropriate matrix components using published data for guidance. Actinide ions will be introduced in the oxidation states pertinent to process conditions. The authors will characterize the speciation of the actinides in the sludges using a variety of techniques. In parallel studies, they will address the chemistry of actinide ions in alkaline solutions, principally those containing chelating agents. The third critical element of this research will be to assess the impact of radiolysis on actinide behavior. By correlating actinide speciation in the solid and solution phases with sludge composition, it will be possible to predict conditions favoring mobilization (or immobilization) of actinide ions during sludge washing. The new information will increase predictability of actinide behavior during tank sludge washing, and so contribute to minimization of the volume of high level waste created

  3. Effects of waste activated sludge and surfactant addition on primary sludge hydrolysis and short-chain fatty acids accumulation.

    Science.gov (United States)

    Ji, Zhouying; Chen, Guanlan; Chen, Yinguang

    2010-05-01

    This paper focused on the effects of waste activated sludge (WAS) and surfactant sodium dodecylbenzene sulfonate (SDBS) addition on primary sludge (PS) hydrolysis and short-chain fatty acids (SCFA) accumulation in fermentation. The results showed that sludge hydrolysis, SCFA accumulation, NH(4)(+)-N and PO(4)(3-)-P release, and volatile suspended solids (VSS) reduction were increased by WAS addition to PS, which were further increased by the addition of SDBS to the mixture of PS and WAS. Acetic, propionic and valeric acids were the top three SCFA in all experiments. Also, the fermentation liquids of PS, PS+WAS, and PS+WAS+SDBS were added, respectively, to municipal wastewater to examine their effects on biological municipal wastewater treatment, and the enhancement of both wastewater nitrogen and phosphorus removals was observed compared with no fermentation liquid addition. PMID:20096564

  4. SULFUR POLYMER STABILIZATION/SOLIDIFICATION (SPSS) TREATABILITY OF SIMULATED MIXED-WASTE MERCURY CONTAMINATED SLUDGE

    International Nuclear Information System (INIS)

    The Environmental Protection Agency (EPA) is currently evaluating alternative treatment standards for radioactively contaminated high mercury (Hg) subcategory wastes, which do not require the removal of mercury from the waste. The Sulfur Polymer Stabilization/Solidification (SPSS) process developed at Brookhaven National Laboratory is one of several candidate technologies capable of successfully treating various Hg waste streams. To supplement previously supplied data on treatment of soils, EPA needed additional data concerning stabilization of high Hg subcategory waste sludges. To this end, a 5000 ppm sludge surrogate, containing approximately 50 wt% water, was successfully treated by pilot-scale SPSS processing. In two process runs, 85 and 95 wt% of water was recovered from the sludge during processing. At waste loadings of 46 wt% (30 wt% dry) sludge, the treated waste form had no detectable mercury (<10 ppb) in TCLP leachates. Data gathered from the demonstration of treatment of this sludge will provide the EPA with information to support revisions to current treatment requirements for high Hg subcategory wastes

  5. Actinides in alkaline media: dissolution, mineral associations, and speciation in hanford waste tank sludge simulants

    International Nuclear Information System (INIS)

    We have investigated the leaching behavior of actinides from simulants of tank waste sludges derived from the BiPO4, Redox, and PUREX processes, the principal chemical separations processes that operated at the Hanford site during 40+years of plutonium production. Fundamental investigations of the speciation of uranium and neptunium in solutions representative of proposed alkaline sludge washing liquors have also been completed. Correlation of the results from sludge leaching indicate that, while Am and Pu are generally not appreciably dissolved from the sludges into alkaline solutions in the absence of oxidants, Np and U can be mobilized during alkaline sludge washing. Leaching of sludges with acidic solutions and strong complexing agents indicate considerable association of all actinide ions with Cr, Fe, and Mn oxides in the sludge simulants. Electrochemical experiments conducted in strongly alkaline solutions have defined the formal potentials of Np in strong base and reveal that mononuclear hydrolysis products dominate the speciation of neptunium (and by analogy U and Pu) in concentrated alkali. The results of these observations are discussed in the context of alkaline sludge washing procedures associated with waste tank remediation. This work supported by the Assistant Secretary for Environmental Management under U.S. Department of Energy Contract Numbers W-31-109ENG-38 at Argonne National Laboratory and DE-AC03-76SF0098 at Lawrence Berkeley National Laboratory. (author)

  6. Impact of sludge layer geometry on the hydraulic performance of a waste stabilization pond.

    Science.gov (United States)

    Ouedraogo, Faissal R; Zhang, Jie; Cornejo, Pablo K; Zhang, Qiong; Mihelcic, James R; Tejada-Martinez, Andres E

    2016-08-01

    Improving the hydraulic performance of waste stabilization ponds (WSPs) is an important management strategy to not only ensure protection of public health and the environment, but also to maximize the potential reuse of valuable resources found in the treated effluent. To reuse effluent from WSPs, a better understanding of the factors that impact the hydraulic performance of the system is needed. One major factor determining the hydraulic performance of a WSP is sludge accumulation, which alters the volume of the pond. In this study, computational fluid dynamics (CFD) analysis was applied to investigate the impact of sludge layer geometry on hydraulic performance of a facultative pond, typically used in many small communities throughout the developing world. Four waste stabilization pond cases with different sludge volumes and distributions were investigated. Results indicate that sludge distribution and volume have a significant impact on wastewater treatment efficiency and capacity. Although treatment capacity is reduced with accumulation of sludge, the latter may induce a baffling effect which causes the flow to behave closer to that of plug flow reactor and thus increase treatment efficiency. In addition to sludge accumulation and distribution, the impact of water surface level is also investigated through two additional cases. Findings show that an increase in water level while keeping a constant flow rate can result in a significant decrease in the hydraulic performance by reducing the sludge baffling effect, suggesting a careful monitoring of sludge accumulation and water surface level in WSP systems. PMID:27176549

  7. Characterization of Actinides in Simulated Alkaline Tank Waste Sludges and Leachates

    International Nuclear Information System (INIS)

    During sludge washing procedures associated with tank waste remediation, actinide ions are expected to remain with the insoluble metal oxide/hydroxide residue as the sludges are scrubbed to remove Cr, P, Al, S, and thus to be transmitted conveniently to the vitrification plant. Unfortunately, in laboratory tests with actual sludge samples alkaline sludge treatment has proven less efficacious for Al and Cr removal than was hoped. To improve removal of Al and Cr, more aggressive treatments of sludges are anticipated, including contact with oxidants targeting Cr(III). In addition, our prior research on the alkaline scrubbing of sludge simulants indicated higher than expected ''solubilization'' of Np and U into concentrated alkali, and some tendency for Am to be mobilized in contact with oxidants. In this project, we are investigating the fundamental chemistry of actinides in sludge simulants under representative oxidative leaching conditions. We are also examining acidic leaching with concurrent secondary separations to enhance Al removal. Our objective is to provide adequate insight into actinide behavior under these conditions to enable prudent decision making as tank waste treatment protocols develop. We expect to identify those components of sludges that are likely to be problematic in the application of oxidative leaching protocols

  8. Fenton peroxidation improves the drying performance of waste activated sludge.

    Science.gov (United States)

    Dewil, Raf; Baeyens, Jan; Neyens, Elisabeth

    2005-01-31

    Advanced sludge treatment processes (AST) reduce the amount of sludge produced and improve the dewaterability, thus probably also affecting the heat transfer properties and the drying characteristics of the sludge. This paper studies the influence of the Fenton peroxidation on the thermal conductivity of the sludge. Results demonstrate that the Fenton's peroxidation positively influences the sludge cake consistency and hence enhances the mechanical dewaterability and the drying characteristics of the dewatered sludge. For the two sludges used in this study, i.e. obtained from the wastewater treatment plants (WWTP) of Tienen and Sint-Niklaas--the dry solids content of the mechanically dewatered sludge increased from 22.5% to 40.3% and from 18.7% to 35.2%, respectively. The effective thermal conductivity k(e) of the untreated and the peroxidized sludges is measured and used to determine the heat transfer coefficient h(s). An average improvement for k(e) of 16.7% (Tienen) and 5.8% (Sint-Niklaas) was observed. Consequently the value of h(s) increased with 15.6% (Tienen) and 5.0% (Sint-Niklaas). This increased heat transfer coefficient in combination with the increased dewaterability has direct implications on the design of sludge dryers. A plate-to-plate calculation of a multiple hearth dryer illustrates that the number of plates required to dry the peroxidized sludge to 90% DS is less than half the number of plates needed to dry untreated sludge. This results in reduced dryer dimensions or a higher capacity for an existing dryer of given dimensions. PMID:15629575

  9. Ultrasonic waste activated sludge disintegration for recovering multiple nutrients for biofuel production.

    Science.gov (United States)

    Xie, Guo-Jun; Liu, Bing-Feng; Wang, Qilin; Ding, Jie; Ren, Nan-Qi

    2016-04-15

    Waste activated sludge is a valuable resource containing multiple nutrients, but is currently treated and disposed of as an important source of pollution. In this work, waste activated sludge after ultrasound pretreatment was reused as multiple nutrients for biofuel production. The nutrients trapped in sludge floc were transferred into liquid medium by ultrasonic disintegration during first 30 min, while further increase of pretreatment time only resulted in slight increase of nutrients release. Hydrogen production by Ethanoligenens harbinense B49 from glucose significantly increased with the concentration of ultrasonic sludge, and reached maximum yield of 1.97 mol H2/mol glucose at sludge concentration of 7.75 g volatile suspended solids/l. Without addition of any other chemicals, waste molasses rich in carbohydrate was efficiently turned into hydrogen with yield of 189.34 ml H2/g total sugar by E. harbinense B49 using ultrasonic sludge as nutrients. The results also showed that hydrogen production using pretreated sludge as multiple nutrients was higher than those using standard nutrients. Acetic acid produced by E. harbinense B49 together with the residual nutrients in the liquid medium were further converted into hydrogen (271.36 ml H2/g total sugar) by Rhodopseudomonas faecalis RLD-53 through photo fermentation, while ethanol was the sole end product with yield of 220.26 mg/g total sugar. Thus, pretreated sludge was an efficient nutrients source for biofuel production, which could replace the standard nutrients. This research provided a novel strategy to achieve environmental friendly sludge disposal and simultaneous efficient biofuel recovery from organic waste. PMID:26896823

  10. Bioproduction of volatile fatty acid from the fermentation of waste activated sludge for in situ denitritation.

    Science.gov (United States)

    Wang, Bo; Peng, Yongzhen; Guo, Yuanyuan; Wang, Shuying

    2016-04-01

    Waste activated sludge (WAS) fermentation integrated with denitritation (the reduction of nitrite to dinitrogen gas) at different pHs was investigated in batch-mode reactors over a 24-day period. The results showed that in comparison with controlled pHs, the volatile fatty acid (VFA) bioproduction for in situ denitritation was significantly improved at uncontrolled pH. VFA fermented from WAS was quickly consumed by denitritation at uncontrolled pH, which accelerated sludge degradation. On the other hand, sludge digestion was benefited from the alkalinity produced from denitritation, while methanogenesis was prohibited by alkalinity and nitrite. The integrated sludge fermentation and denitritation can be cost-effectively applied to wastewater treatment plants, so that organic substrates (e.g., VFAs) are produced for denitritation via simultaneous sludge fermentation, which enables WAS reutilization and enhances nitrogen removal efficiency without the need of external carbon sources. PMID:26475401

  11. Reduction of Fecal Streptococcus and Salmonella by selected treatment methods for sludge and organic waste

    DEFF Research Database (Denmark)

    Jepsen, Svend Erik; Krause, Michael; Grüttner, Henrik

    1997-01-01

    The increasing utilization of waste water sludge and source-separated organic household waste in agriculture has brought the quality aspects into focus, among others the hygienic aspects. In this study, the reducting effect on Fecal Streptococcus (FS) and Salmonella of different methods for...... waste have shown reductions of microorganisms allowing for unrestricted utilization in agriculture, meeting the product control:FS below 100/g and no Salmonella detected. The effect of storage of sludge at summer and winter temperatures respectively has been investigated. At temperatures (around 20°C...

  12. Recovery of Zinc Waste Galvanic Sludges with Increased Copper and Nickel Content

    Czech Academy of Sciences Publication Activity Database

    Jandová, J.; Dvořák, P.; Jiřičný, Vladimír

    Vol. 2. Madrid, 2004 - (Gaballah, I.; Mishra, B.; Solozabal, R.; Tanaka, M.), s. 1883-1891 ISBN 84-95520-05-2. [ Global Symposium on Recycling, Waste Treatment and Clean Technology REWAS 2004. Madrid (ES), 26.09.2004-29.09.2004] Institutional research plan: CEZ:AV0Z4072921 Keywords : zinc waste * galvanic sludge * nickel Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  13. Hybrid alkali-hydrodynamic disintegration of waste-activated sludge before two-stage anaerobic digestion process

    OpenAIRE

    Grübel, Klaudiusz; Suschka, Jan

    2014-01-01

    The first step of anaerobic digestion, the hydrolysis, is regarded as the rate-limiting step in the degradation of complex organic compounds, such as waste-activated sludge (WAS). The aim of lab-scale experiments was to pre-hydrolyze the sludge by means of low intensive alkaline sludge conditioning before applying hydrodynamic disintegration, as the pre-treatment procedure. Application of both processes as a hybrid disintegration sludge technology resulted in a higher organic matter release (...

  14. Can aquatic worms enhance methane production from waste activated sludge?

    Science.gov (United States)

    Serrano, Antonio; Hendrickx, Tim L G; Elissen, Hellen H J; Laarhoven, Bob; Buisman, Cees J N; Temmink, Hardy

    2016-07-01

    Although literature suggests that aquatic worms can help to enhance the methane production from excess activated sludge, clear evidence for this is missing. Therefore, anaerobic digestion tests were performed at 20 and at 30°C with sludge from a high-loaded membrane bioreactor, the aquatic worm Lumbriculus variegatus, feces from these worms and with mixtures of these substrates. A significant synergistic effect of the worms or their feces on methane production from the high-loaded sludge or on its digestion rate was not observed. However, a positive effect on low-loaded activated sludge, which generally has a lower anaerobic biodegradability, cannot be excluded. The results furthermore showed that the high-loaded sludge provides an excellent feed for L. variegatus, which is promising for concepts where worm biomass is considered a resource for technical grade products such as coatings and glues. PMID:26998797

  15. Co-digestion of mixed industrial sludge with municipal solid wastes in anaerobic simulated landfilling bioreactors

    International Nuclear Information System (INIS)

    In this study, the feasibility of the anaerobic co-digestion of a mixed industrial sludge with municipal solid wastes (MSW) was investigated in three simulated anaerobic landfilling bioreactors during a 150-day period. All of the reactors were operated with leachate recirculation. One of them was loaded only with MSW (control reactor); the second reactor was loaded with mixed industrial sludge and MSW, the weight ratio of the MSW to mixed industrial sludge was 1:1 (based on dry solid) (Run 1); the third reactor was loaded with mixed industrial sludge and MSW, the weight ratio of the MSW to mixed industrial sludge was 1:2 (based on dry solid) (Run 2). The VFA concentrations decreased significantly in Run 1 and Run 2 reactors at the end of 150 days. The pH values were higher in Run 1 and Run 2 reactors compared to control reactor. The differences between leachate characteristics, the biodegradation and the bioefficiency of the reactors were compared. The NH4-N concentrations released to leachate from mixed sludge in Run 1 and Run 2 reactors were lower than that of control reactor. The BOD5/COD ratios in Run 1 and Run 2 reactors were lower than that of control reactor at the end of 150 days. Cumulative methane gas productions and methane percentages were higher in Run 1 and Run 2 reactors. Reductions in waste quantity, carbon percentage and settlement of the waste were better in Run 1 and Run 2 reactors compared to control reactor at the end of 150 days. Furthermore, TN and TP removals in waste were higher in reactors containing industrial sludge compared to control. The toxicity test results showed that toxicity was observed in reactors containing industrial mixed sludge

  16. Nitrogen removal from wastewater and external waste activated sludge reutilization/reduction by simultaneous sludge fermentation, denitrification and anammox (SFDA).

    Science.gov (United States)

    Wang, Bo; Peng, Yongzhen; Guo, Yuanyuan; Zhao, Mengyue; Wang, Shuying

    2016-08-01

    This work demonstrates the feasibility of simultaneous nitrogen removal and external waste activated sludge (WAS) reutilization/reduction by using the synergy of sludge fermentation, denitrification and anammox processes in up-flow reactors (SFDA). Pre-treated domestic wastewater and synthetic wastewater (containing nitrite ∼20mg/L, ammonium ∼10mg/L in both) were fed to 1# and 2# SFDA, respectively. Long-term operation of 1# SFDA was investigated with achieving the peak ammonium removal rate of 0.021 and nitrite removal rate of 0.081kgN/(m(3)d) as nitrogen loading rate elevated from 0.075 to 0.106kgN/(m(3)d). Negative effect of dissolved oxygen on anammox or fermentation in the 2# SFDA was demonstrated negligible due to rapid depletion by microorganisms. Furthermore, a "net" sludge reduction of 38.8% was obtained due to sludge decay and organics consumption by denitrification. The SFDA process was expected to potentially be used for nitrogen removal and WAS reutilization/reduction in full-scale application. PMID:27140818

  17. Effects of Metal Nanoparticles on Methane Production from Waste-Activated Sludge and Microorganism Community Shift in Anaerobic Granular Sludge

    Science.gov (United States)

    Wang, Tao; Zhang, Dong; Dai, Lingling; Chen, Yinguang; Dai, Xiaohu

    2016-05-01

    Extensive use of nanoparticles (NPs) in consumer and industrial products has led to concerns about their potential environmental impacts; however, the influences of different NPs (e.g., nZVI (nano zero-valent iron), Ag NPs, Fe2O3 NPs and MgO NPs) on the anaerobic digestion of sludge have not yet been studied in depth. Additionally, a new guideline or the use of different NPs in the anaerobic digestion of sludge should be established to improve the anaerobic digestion of sludge and avoid inhibitory effects. This study investigated the effects of four representative NPs (i.e., nZVI, Ag NPs, Fe2O3 NPs and MgO NPs) on methane production during the anaerobic digestion of waste activated sludge (WAS). The presence of 10 mg/g total suspended solids (TSS) nZVI and 100 mg/g TSS Fe2O3 NPs increased methane production to 120% and 117% of the control, respectively, whereas 500 mg/g TSS Ag NPs and 500 mg/g TSS MgO NPs generated lower levels of methane production (73.52% and 1.08% that of the control, respectively). These results showed that low concentrations of nZVI and Fe2O3 NPs promoted the amount of microbes (Bacteria and Archaea) and activities of key enzymes but that higher concentrations of Ag NPs and MgO NPs inhibited them.

  18. Effects of Metal Nanoparticles on Methane Production from Waste-Activated Sludge and Microorganism Community Shift in Anaerobic Granular Sludge.

    Science.gov (United States)

    Wang, Tao; Zhang, Dong; Dai, Lingling; Chen, Yinguang; Dai, Xiaohu

    2016-01-01

    Extensive use of nanoparticles (NPs) in consumer and industrial products has led to concerns about their potential environmental impacts; however, the influences of different NPs (e.g., nZVI (nano zero-valent iron), Ag NPs, Fe2O3 NPs and MgO NPs) on the anaerobic digestion of sludge have not yet been studied in depth. Additionally, a new guideline or the use of different NPs in the anaerobic digestion of sludge should be established to improve the anaerobic digestion of sludge and avoid inhibitory effects. This study investigated the effects of four representative NPs (i.e., nZVI, Ag NPs, Fe2O3 NPs and MgO NPs) on methane production during the anaerobic digestion of waste activated sludge (WAS). The presence of 10 mg/g total suspended solids (TSS) nZVI and 100 mg/g TSS Fe2O3 NPs increased methane production to 120% and 117% of the control, respectively, whereas 500 mg/g TSS Ag NPs and 500 mg/g TSS MgO NPs generated lower levels of methane production (73.52% and 1.08% that of the control, respectively). These results showed that low concentrations of nZVI and Fe2O3 NPs promoted the amount of microbes (Bacteria and Archaea) and activities of key enzymes but that higher concentrations of Ag NPs and MgO NPs inhibited them. PMID:27166174

  19. Reduction of heavy metals in refinery waste sludge using em treatment

    International Nuclear Information System (INIS)

    This paper presents the efforts of National Cleaner Production Center (NCPC) and Attock Refinery Limited (ARL) Rawalpindi, to address the problem of refinery solid waste. A trial project was designed to treat and convert 1.7 m ton to oil sludge into environmental friendly residue (compost) under anaerobic conditions. The residue can be treated as bio fertilizer for agricultural purpose. The trial on bio remediation (anaerobic) of oily sludge of ARL, Rawalpindi within its premises using EM technology was successfully completed with the collaboration of effective microorganism research organization (EMRO), NCPC and ARL between 29th October to 10th December, 2002. The effective microorganisms transformed the undiluted oily sludge from ARL into bioactive sludge; which may be called as bio sludge. For heavy metal breakdown the trial data shows that Ba has been reduced by 85% in the EM. Treated oily sludge as compared to original ARL sludge, and Pb, Fe, Zn and Ni have been reduced by about 50% in the treated bio sludge. The contents of As, Cr, Cu and Mn showed no change. The residue obtained can be used as a bio fertilizer. (author)

  20. Composting sewage sludge with green waste from tree pruning

    Directory of Open Access Journals (Sweden)

    Sarah Mello Leite Moretti

    2015-10-01

    Full Text Available Sewage sludge (SS has been widely used as organic fertilizer. However, its continuous use can cause imbalances in soil fertility as well as soil-water-plant system contamination. The study aimed to evaluate possible improvements in the chemical and microbiological characteristics of domestic SS, with low heavy metal contents and pathogens, through the composting process. Two composting piles were set up, based on an initial C/N ratio of 30:1, with successive layers of tree pruning waste and SS. The aeration of piles was performed by mechanical turnover when the temperature rose above 65 ºC. The piles were irrigated when the water content was less than 50 %. Composting was conducted for 120 days. Temperature, moisture content, pH, electrical conductivity (EC, carbon and nitrogen contents, and fecal coliforms were monitored during the composting. A reduction of 58 % in the EC of the compost (SSC compared with SS was observed and the pH reduced from 7.8 to 6.6. There was an increase in the value of cation exchange capacity/carbon content (CEC/C and carbon content. Total nitrogen remained constant and N-NO3- + N-NH4+ were immobilised in organic forms. The C/N ratio decreased from 25:1 to 12:1. Temperatures above 55 ºC were observed for 20 days. After 60 days of composting, fecal coliforms were reduced from 107 Most Probable Number per gram of total solids (MPN g−1 to 104 MPN g−1. I one pile the 103 MPN g−1 reached after 90 days in one pile; in another, there was recontamination from 105 to 106 MPN g−1. In SSC, helminth eggs were eliminated, making application sustainable for agriculture purposes.

  1. "Isolation and Identification of Bacteria Present in the Activated Sludge Unit, in the Treatment of Industrial Waste Water "

    OpenAIRE

    MK Sharifi-Yazdi; C. Azimi; MB Khalili

    2001-01-01

    Activated sludge or extended aeration treatment involves a continous system where aerobic biological growths are mixed with waste water and then separated in a gravity clarifier. Therefore, waste treatment system such as the activated sludge system depend on the activities of communities of living organism. In this study, an attempt was made on the indentification of the bacterial population involved in the laboratory activated sludge unit. The results showed that gram-negative bacilli with a...

  2. Chemical stabilization of mine waste with sewage sludge and calcium carbonate residues

    OpenAIRE

    Höckert, Linda

    2007-01-01

    Chemical stabilization of mine waste from Ljusnarsbergsfältet with sewage sludge and calcium carbonate residues Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purp...

  3. Treatment of off-gas evolved from thermal decomposition of sludge waste

    International Nuclear Information System (INIS)

    Korea Atomic Energy Research Institute (KAERI) started a decommissioning program of a uranium conversion plant. The treatment of the sludge waste, which was generated during the operation of the plant, is one of the most important tasks in the decommissioning program of the plant. The major compounds of sludge waste are nitrate salts and uranium. The sludge waste is denitrated by thermal decomposition. The treatment of off-gas evolved from the thermal decomposition of nitrate salts in the sludge waste is investigated. The nitrate salts in the sludge were decomposed in two steps: the first decomposition is due to the ammonium nitrate, and the second is due to the sodium and calcium nitrate and calcium carbonate. The components of off-gas from the decomposition of ammonium nitrate at low temperature are NH3, N2O, NO2, and NO. In addition, the components from the decomposition of sodium and calcium nitrate at high temperature are NO2 and NO. Off-gas from the thermal decomposition is treated by the catalytic oxidation of ammonia and selective catalytic reduction (SCR). Ammonia is converted into nitrogen oxides through the oxidation catalyst and all nitrogen oxides are removed by SCR treatment besides nitrous oxide, which is greenhouse gas. An additional process is needed to remove nitrous oxide, and the feeding rate of ammonia in SCR should be controlled properly for evolved nitrogen oxides. (author)

  4. HIGH LEVEL WASTE MECHANCIAL SLUDGE REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT

    International Nuclear Information System (INIS)

    The Savannah River Site F-Tank Farm Closure project has successfully performed Mechanical Sludge Removal (MSR) using the Waste on Wheels (WOW) system for the first time within one of its storage tanks. The WOW system is designed to be relatively mobile with the ability for many components to be redeployed to multiple waste tanks. It is primarily comprised of Submersible Mixer Pumps (SMPs), Submersible Transfer Pumps (STPs), and a mobile control room with a control panel and variable speed drives. In addition, the project is currently preparing another waste tank for MSR utilizing lessons learned from this previous operational activity. These tanks, designated as Tank 6 and Tank 5 respectively, are Type I waste tanks located in F-Tank Farm (FTF) with a capacity of 2,840 cubic meters (750,000 gallons) each. The construction of these tanks was completed in 1953, and they were placed into waste storage service in 1959. The tank's primary shell is 23 meters (75 feet) in diameter, and 7.5 meters (24.5 feet) in height. Type I tanks have 34 vertically oriented cooling coils and two horizontal cooling coil circuits along the tank floor. Both Tank 5 and Tank 6 received and stored F-PUREX waste during their operating service time before sludge removal was performed. DOE intends to remove from service and operationally close (fill with grout) Tank 5 and Tank 6 and other HLW tanks that do not meet current containment standards. Mechanical Sludge Removal, the first step in the tank closure process, will be followed by chemical cleaning. After obtaining regulatory approval, the tanks will be isolated and filled with grout for long-term stabilization. Mechanical Sludge Removal operations within Tank 6 removed approximately 75% of the original 95,000 liters (25,000 gallons). This sludge material was transferred in batches to an interim storage tank to prepare for vitrification. This operation consisted of eleven (11) Submersible Mixer Pump(s) mixing campaigns and multiple intraarea

  5. Increased CPC batch size study for Tank 42 sludge in the Defense Waste Processing Facility

    International Nuclear Information System (INIS)

    A series of experiments have been completed at TNX for the sludge-only REDOX adjusted flowsheet using Tank 42 sludge simulant in response to the Technical Task Request HLW/DWPT/TTR-980013 to increase CPC batch sizes. By increasing the initial SRAT batch size, a melter feed batch at greater waste solids concentration can be prepared and thus increase melter output per batch by about one canister. The increased throughput would allow DWPF to dispose of more waste in a given time period thus shortening the overall campaign

  6. Engineering properties of sintered waste sludge as lightweight aggregate in a densified concrete mixture

    Institute of Scientific and Technical Information of China (English)

    彭予柱

    2009-01-01

    The global trend towards carbon reduction,energy conservation,and sustainable use of resources has led to an increased focus on the use of waste sludge in construction.We used waste sludge from a reservoir to produce high-strength sintered lightweight aggregate,and then used the densified mixture design algorithm to create high-performance concrete from the sintered aggregate with only small amounts of mixing water and cement.Ultrasonic,electrical resistance and concrete strength efficiency tests were perfo...

  7. Methods for reducing the infection hazard of waste-water sludge

    International Nuclear Information System (INIS)

    The most commonly used disposal practices for digested sewage sludge in the United States of America are disposal to landfill, agricultural use, incineration and disposal to the ocean. About a quarter of the sludge produced is used for agricultural purposes. The US Congress has been strongly urging more beneficial use of waste-water and waste-water sludge. However, plant location and other consideration, such as the high metals content of many sludges, make it unlikely that the proportion of sludge used on the land will increase markedly in the near future. A portion of the sludge used on the land must be attenuated in content of infectious material below that obtained by conventional digestion processes. One method for reducing infection hazard is high-energy irradiation. However, this method must compete with other methods such as pasteurization, long-term lagooning, thermophilic anaerobic digestion and thermophilic aerobic digestion. The high-energy irradiation method offers several advantages, particularly high reliability, but its cost must be competitive with other methods to gain acceptance. (author)

  8. Potential for land application of contaminated sewage sludge treated with fermented liquid from pineapple wastes.

    Science.gov (United States)

    Del Mundo Dacera, Dominica; Babel, Sandhya; Parkpian, Preeda

    2009-08-15

    The suitability for land application of anaerobically digested sewage sludge treated with naturally fermented and Aspergillus niger (A. niger) fermented raw liquid from pineapple wastes, in terms of changes in the forms and amount of heavy metals and nutrient and pathogen content, were investigated in this study. Leaching studies for fermented liquid at optimum conditions (pH and contact time with best metal removal efficiencies) were carried out for the removal of Cd, Cr, Cu, Pb, Ni and Zn from sewage sludge, with citric acid as a reference. Using the same sludge before and after leaching, sequential fractionation studies were done to observe the effect of treatment on the forms of metals in sludge and their mobility and bioavailability. Results of laboratory scale studies revealed that leaching with all extractants at selected optimum conditions resulted in a decrease in heavy metals and pathogen content of the treated sludge, presence of sufficient amount of nutrients (nitrogen and phosphorous) and dominance of residual fractions in most metals, with sludge treated with A. niger, having the best quality. The results, therefore, indicate the high potential of the treated sludge for land application, with no harm from heavy metals released and no toxicity to the soil and groundwater. PMID:19232826

  9. An Experimental Investigation of Partial Replacement of Cement by Industrial Waste (Hypo Sludge

    Directory of Open Access Journals (Sweden)

    Mr.R.Balamurugan

    2014-04-01

    Full Text Available Concrete is strength and tough material but it is porous material also which interacts with the surrounding environment. The durability of concrete depends largely on the movement of water and gas enters and moves through it. To produce low cost concrete by blending various ratios of cement with hypo sludge & to reduce disposal and pollution problems due to hypo sludge it is most essential to develop profitable building materials from hypo sludge. To make good quality paper limited number of times recycled Paper fibers can be used which produces a large amount of solid waste. The innovative use of hypo sludge in concrete formulations as a supplementary cementations material was tested as an alternative to traditional concrete.

  10. Enhancing denitrification using a carbon supplement generated from the wet oxidation of waste activated sludge.

    Science.gov (United States)

    Strong, P J; McDonald, B; Gapes, D J

    2011-05-01

    This study compared the effect of four pure carbon supplements on biological denitrification to a liquor derived as a by-product from the wet oxidation (WO) of waste activated sludge. Sequencing batch reactors were used to acclimate sludge biomass, which was used in batch assays. Acetate, WO liquor and ethanol-supplementation generated the fastest denitrification rates. Acetate and WO liquor were efficiently utilised by all acclimated biomass types, while poor rates were achieved with methanol and formate. When comparing an inoculum from an ethanol-supplemented and non-supplemented wastewater treatment plant (WWTP), the ethanol-acclimated sludge obtained superior denitrification rates when supplemented with ethanol. Similarly high nitrate removal rates were achieved with both sludge types with acetate and WO liquor supplementation, indicating that WO liquors could achieve excellent rates of nitrate removal. The performance of the WO liquor was attributed to the variety of organic carbon substrates (particularly acetic acid) present within the liquor. PMID:21196117

  11. Assessment and analysis of industrial liquid waste and sludge disposal at unlined landfill sites in arid climate

    International Nuclear Information System (INIS)

    Municipal solid waste disposal sites in arid countries such as Kuwait receive various types of waste materials like sewage sludge, chemical waste and other debris. Large amounts of leachate are expected to be generated due to the improper disposal of industrial wastewater, sewage sludge and chemical wastes with municipal solid waste at landfill sites even though the rainwater is scarce. Almost 95% of all solid waste generated in Kuwait during the last 10 years was dumped in five unlined landfills. The sites accepting liquid waste consist of old sand quarries that do not follow any specific engineering guidelines. With the current practice, contamination of the ground water table is possible due to the close location of the water table beneath the bottom of the waste disposal sites. This study determined the percentage of industrial liquid waste and sludge of the total waste dumped at the landfill sites, analyzed the chemical characteristics of liquid waste stream and contaminated water at disposal sites, and finally evaluated the possible risk posed by the continuous dumping of such wastes at the unlined landfills. Statistical analysis has been performed on the disposal and characterization of industrial wastewater and sludge at five active landfill sites. The chemical analysis shows that all the industrial wastes and sludge have high concentrations of COD, suspended solids, and heavy metals. Results show that from 1993 to 2000, 5.14±1.13 million t of total wastes were disposed per year in all active landfill sites in Kuwait. The share of industrial liquid and sludge waste was 1.85±0.19 million t representing 37.22±6.85% of total waste disposed in all landfill sites. Such wastes contribute to landfill leachate which pollutes groundwater and may enter the food chain causing adverse health effects. Lined evaporation ponds are suggested as an economical and safe solution for industrial wastewater and sludge disposal in the arid climate of Kuwait

  12. Low-Temperature, Vacuum-Aided Thermal Desorption Studies on a Simulated Organic Sludge Waste

    International Nuclear Information System (INIS)

    This report describes an initial set of small scale lab tests conducted on surrogate waste materials to investigate mass release behavior of volatile organics (VOC's) from a solidified liquid organic sludge matrix under vacuum-aided, low-temperature thermal desorption conditions. Low temperature thermal desorption is being considered as a potential processing technology alternative to incineration, to remove gas generation limitations affecting the transportation of transuranic (TRU) contaminated organic sludge wastes to a designated off-site repository (i.e., the Waste Isolation Pilot Plant). The lab-scale tests provide initial exploratory level information on temperature profiles and rates of volatile organic desorption for a range of initial VOC/oil liquid mixture concentrations in a calcium silicate matrix, under low temperature heating and vacuum boundary conditions that are representative of potentially desirable ''in-drum desorption'' conditions. The results of these tests indicate that reduced operating pressures have a potential for significantly enhancing the rate of thermal desorption experienced from a liquid organic/oil solidified ''sludge'' waste. Furthermore, the results indicate that in-drum thermal desorption can be performed on organic sludge wastes, at reduced pressures, while maintaining an operating temperature sufficiently low to prevent destruction of the waste drum packaging materials (confinement) surrounding the waste. The results also indicate that VOC release behavior/rates in the vacuum thermal desorption process cannot be represented by a simple liquid-liquid mass-diffusion model, since overall mass release rates observed are generally two orders of magnitude greater than predicted by simple liquid-liquid mass diffusion. This is partially attributed to the effects of the transient temperature profiles within the sludge during heat up; however, the primary cause is thought to be micro boiling of the volatile organics within the

  13. Environmental and resource implications of phosphorus recovery from waste activated sludge.

    Science.gov (United States)

    Sørensen, Birgitte Lilholt; Dall, Ole Leinikka; Habib, Komal

    2015-11-01

    Phosphorus is an essential mineral resource for the growth of crops and thus necessary to feed the ever increasing global population. The essentiality and irreplaceability of phosphorus in food production has raised the concerns regarding the long-term phosphorus availability and the resulting food supply issues in the future. Hence, the recovery of phosphorus from waste activated sludge and other waste streams is getting huge attention as a viable solution to tackle the potential availability issues of phosphorus in the future. This study explores the environmental implications of phosphorus recovery from waste activated sludge in Denmark and further elaborates on the potential availability or scarcity issue of phosphorus today and 2050. Life cycle assessment is used to assess the possibility of phosphorus recovery with little or no environmental impacts compared to the conventional mining. The phosphorus recovery method assessed in this study consists of drying process, and thermal gasification of the waste activated sludge followed by extraction of phosphorus from the ashes. Our results indicate that the environmental impacts of phosphorus recovery in an energy efficient process are comparable to the environmental effects from the re-use of waste activated sludge applied directly on farmland. Moreover, our findings conclude that the general recommendation according to the waste hierarchy, where re-use of the waste sludge on farmland is preferable to material and energy recovery, is wrong in this case. Especially when phosphorus is a critical resource due to its life threatening necessity, lack of substitution options and potential future supply risk originating due to the high level of global supply concentration. PMID:25792438

  14. Hazardous Waste Code Determinations for the First/Second Stage Sludge Waste Stream (IDCs 001, 002, 800)

    Energy Technology Data Exchange (ETDEWEB)

    Arbon, Rodney Edward

    2001-01-01

    This document, Hazardous Waste Code Determination for the First/Second-Stage Sludge Waste Stream, summarizes the efforts performed at the Idaho National Engineering and Environmental Laboratory (INEEL) to make a hazardous waste code determination on Item Description Codes (IDCs) 001, 002, and 800 drums. This characterization effort included a thorough review of acceptable knowledge (AK), physical characterization, waste form sampling, chemical analyses, and headspace gas data. This effort included an assessment of pre-Waste Analysis Plan (WAP) solidified sampling and analysis data (referred to as preliminary data). Seventy-five First/Second-Stage Sludge Drums, provided in Table 1-1, have been subjected to core sampling and analysis using the requirements defined in the Quality Assurance Program Plan (QAPP). Based on WAP defined statistical reduction, of preliminary data, a sample size of five was calculated. That is, five additional drums should be core sampled and analyzed. A total of seven drums were sampled, analyzed, and validated in compliance with the WAP criteria. The pre-WAP data (taken under the QAPP) correlated very well with the WAP compliant drum data. As a result, no additional sampling is required. Based upon the information summarized in this document, an accurate hazardous waste determination has been made for the First/Second-Stage Sludge Waste Stream.

  15. Potential of Waste Water Sludge as Environmental-Friendly Manure after UV-Treatment

    Directory of Open Access Journals (Sweden)

    Laila Zafar

    2012-10-01

    Full Text Available Due to exponential population increase in developing world, the wastewater and solid waste generation has tremendously increased and their management has become a serious health and environmental issue. A large amount of sewage sludge generated by sewage treatment plants however, can be re-used after proper segregation and treatment as fertilizer and for energy production. Hence, this study was carried out to find out the potential use of sludge produced at Islamabad Capital Territory (ICT Sewage Treatment Plant (STP as organic fertilizer. For this purpose, chemical analysis of the waste water was carried out to determine the quality of raw waste water (influent and treated waste water (effluent intermittently. Furthermore, post-wastewater treatment, sewage sludge was analyzed for its chemical characteristics, i.e., for Total Nitrogen (TN, Total Phosphorous (TP and Organic Matter (OM contents; and microbial analyses for the presence of Total Coliforms, Fecal Coliforms and E. Coli was also carried out sewage sludge was exposed to sunlight for 0, 3 and 6 months. The results were with commercial compost (control similar characteristics. According to the results, pH, EC, TSS, COD and BOD5 were found very high in the influent however, after the waste water treatment; the effluent quality was found within the limits of National Environmental Quality standards (NEQs. On the other hand, TN, TP and OM content remained high in sewage sludge as compared to the controls. In order to enumerate harmful microbes in sewage sludge, microbial analyses for Total Coliforms, Fecal Coliforms and E. coli was carried out in pre-treated, UV-post-treated and control sludge samples. According to the results, the Total and Fecal Coliforms were found very high (>16000 MPN/g whereas, E. Coli population remained between (7000-12000 MPN/g. The most important aspect noted in this study was: as the sludge aged, this figure (7,000, 12,000, and 1,600 MPN/g after 0, 3 and 6 months

  16. Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2011-06-08

    Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate’s beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ~60°C, 80°C, and 95°C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal

  17. Performance of calcium peroxide for removal of endocrine-disrupting compounds in waste activated sludge and promotion of sludge solubilization.

    Science.gov (United States)

    Zhang, Ai; Wang, Jie; Li, Yongmei

    2015-03-15

    Removal of six phenolic endocrine disrupting compounds (EDCs) (estrone, 17β-estradiol, 17α-ethinylestradiol, estriol, bisphenol A, and 4-nonylphenols) from waste activated sludge (WAS) was investigated using calcium peroxide (CaO2) oxidation. Effects of initial pH and CaO2 dosage were investigated. The impacts of CaO2 treatment on sludge solubilization and anaerobic digestion were also evaluated. Specifically, the role of reactive oxygen species (ROS) in EDC degradation during CaO2 oxidation was tested. Effects of 6 metal ions contained in the sludge matrix on EDC degradation were also evaluated. The results showed that CaO2 treatment can be a promising technology for EDC removal and facilitating sludge reuse. The EDC removal efficiencies increased with the increase in CaO2 dosage. At CaO2 doses of more than 0.34 g per gram of total solid (g g(-1) TS), more than 50% of EDCs were removed in a wide pH range of 2-12. Higher removal efficiencies were achieved at initial pH values of 12 and 2. The products of EDCs during CaO2 oxidation had less estrogenic activity than the originals. Under the conditions of neutral pH and CaO2 dosage = 0.34 g g(-1) TS, the sludge solubilization can be improved by increasing the soluble total organic carbon (STOC) and volatile suspended solids (VSS) reduction by 25% and 27% in 7 d, respectively; the volatile fatty acid (VFA) production was enhanced by 96% in the 15 d following anaerobic digestion. The ROS released by CaO2 are the main factors contributing to EDC removal, among which, hydroxyl radicals (OH) play the most important role. Metal ions contained in the sludge matrix also affected EDC removal. For most cases, Fe, Cu, and Zn had positive effects; Mn and Ag had negative effects; and Mg had an insignificant effect on EDC removal. PMID:25613412

  18. A laboratory-scale test of anaerobic digestion and methane production after phosphorus recovery from waste activated sludge.

    Science.gov (United States)

    Takiguchi, Noboru; Kishino, Machiko; Kuroda, Akio; Kato, Junichi; Ohtake, Hisao

    2004-01-01

    In enhanced biological phosphorus removal (EBPR) processes, activated sludge microorganisms accumulate large quantities of polyphosphate (polyP) intracellularly. We previously discovered that nearly all of polyP could be released from waste activated sludge simply by heating it at 70 degrees C for about 1 h. We also demonstrated that this simple method was applicable to phosphorus (P) recovery from waste activated sludge in a pilot plant-scale EBPR process. In the present study, we evaluated the effect of this sludge processing (heat treatment followed by calcium phosphate precipitation) on anaerobic digestion in laboratory-scale experiments. The results suggested that the sludge processing for P recovery could improve digestive efficiency and methane productivity at both mesophilic (37 degrees C) and thermophilic (53 degrees C) temperatures. In addition, heat-treated waste sludge released far less P into the digested sludge liquor than did untreated waste sludge. It is likely that the P recovery step prior to anaerobic digestion has a potential advantage for controlling struvite (magnesium ammonium phosphate) deposit problems in sludge handling processes. PMID:16233643

  19. Nutrient release, recovery and removal from waste sludge of a biological nutrient removal system.

    Science.gov (United States)

    Wang, Yi; Zheng, Shu-Jian; Pei, Li-Ying; Ke, Li; Peng, Dang-Cong; Xia, Si-Qing

    2014-01-01

    The uncontrolled release of nutrients from waste sludge results in nitrogen and phosphorus overloading in wastewater treatment plants when supernatant is returned to the inlet. A controlled release, recovery and removal of nutrient from the waste sludge of a Biological Nutrient Removal system (BNR) are investigated. Results showed that the supernatant was of high mineral salt, high electrical conductivity and poor biodegradability, in addition to high nitrogen and phosphorus concentrations after the waste sludge was hydrolysed through sodium dodecyl sulphate addition. Subsequently, over 91.8% of phosphorus and 10.5% of nitrogen in the supernatants were extracted by the crystallization method under the conditions of 9.5 pH and 400 rpm. The precipitate was mainly struvite according to X-ray diffraction and morphological examination. A multistage anoxic-oxic Moving Bed Biofilm Reactor (MBBR) was then adopted to remove the residual carbon, nitrogen and phosphorus in the supernatant. The MBBR exhibited good performance in simultaneously removing carbon, nitrogen and phosphorus under a short aeration time, which accounted for 31.25% of a cycle. Fluorescence in situ hybridization analysis demonstrated that nitrifiers presented mainly in floc, although higher extracellular polymeric substance content, especially DNA, appeared in the biofilm. Thus, a combination of hydrolysis and precipitation, followed by the MBBR, can complete the nutrient release from the waste sludge of a BNR system, recovers nutrients from the hydrolysed liquor and removes nutrients from leftovers effectively. PMID:25176308

  20. Biotechnology of intensive aerobic conversion of sewage sludge and food waste into fertilizer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.-Y.; Stabnikova, O.; Show, K.-Y.; Ding, H.-B.; Tay, S.T.-L.; Ivanov, V.; Tay, J.-H.

    2003-07-01

    Biotechnology for intensive aerobic bioconversion of sewage sludge and food waste into fertilizer was developed. The wastes were treated in a closed reactor under controlled aeration, stirring, pH, and temperature at 60{sup o}C, after addition of starter bacterial culture Bacillus thermoamylovorans. The biodegradation of sewage sludge was studied by decrease of volatile solids (VS), content of organic carbon and autofluorescence of coenzyme F{sub 420}. The degradation of anaerobic biomass was faster than biodegradation of total organic matter. The best fertilizer was obtained when sewage sludge was thermally pre-treated, mixed with food waste, chalk, and artificial bulking agent. The content of volatile solid and the content of organic carbon decreased at 24.8% and 13.5% of total solids, respectively, during ten days of bioconversion. The fertilizer was a powder with moisture content of 5%. It was stable, and not toxic for the germination of plant seeds. Addition of 1.0 to 1.5% of this fertilizer to the subsoil increased the growth of different plants tested by 113 to 164 %. The biotechnology can be applied in larger scale for the recycling of sewage sludge and food wastes in Singapore. (author)

  1. Technique for recovering uranium from sludge-like uranium-bearing wastes using hydrochloric acid

    International Nuclear Information System (INIS)

    Sludge-like uranium-bearing wastes generated from uranium refining and conversion R and D facilities are stored at the Ningyo-toge Environmental Engineering Center of the Japan Atomic Energy Agency. So far, approximately 1500 t of uranium wastes with radioactivity levels exceeding 10,000 Bq/g have been generated. We have proposed an environmentally benign aqueous process for recovering uranium from wastes using hydrochloric acid (HCl). This makes it possible to dispose of the wastes easily, and to reclaim uranium as a resource. In this process, first, the uranium content in the calcium fluoride (CaF2) sludge along with the entire sludge is dissolved almost completely in aqueous solutions containing HCl and aluminum chloride. The uranium species are then recovered as peroxide from the CaF2 sludge solution. Their characteristics are similar to those specified for uranium ore concentrate. After recovering the uranium content, the uranium concentration in the solution is reduced to below 0.01 mg/L using an iminodiacetic chelating resin. Also, the uranium concentration of the precipitate generated by the neutralization of the barren solution falls below 1 Bq/g. (author)

  2. Mesophilic anaerobic co-digestion of municipal solid waste and sewage sludge

    DEFF Research Database (Denmark)

    Aghdam, Ehsan Fathi; Kinnunen, V.; Rintala, Jukka A.

    2015-01-01

    This paper presents mesophilic anaerobic digestion (AD) of organic fraction of municipal solid waste (OFMSW), biowaste (BW), sewage sludge (SS), and co-digestion of BW and SS. Average methane yields of 386 ± 54, 385 ± 82, 198 ± 14, and 318 ± 59 L CH4/kg volatile solids (VS) were obtained for OFMSW...

  3. Sludge as dioxins suppressant in hospital waste incineration

    NARCIS (Netherlands)

    M. Yan; X. Li; J. Yang; T. Chen; S. Lu; A.G. Buekens; K. Olie; J. Yan

    2012-01-01

    Nitrogen containing compounds such as ammonia, urea and amines can effectively inhibit the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Sewage sludge accumulates both sulfur and nitrogen during wastewater treatment so it could be used to reduce PCDD/Fs formation. Indee

  4. Issues related to waste sewage sludge drying under superheated steam

    Directory of Open Access Journals (Sweden)

    Hamawand Ihsan

    2015-12-01

    Full Text Available Sewage sludge was dried in a rotary drum dryer under superheated steam. Particle size and moisture content were shown to have significant influences on sticking and agglomeration of the materials. Pouring partially dried sludge (70–80% moisture content, wet basis directly into the screw feeder of the drum dryer resulted in a significant sticking to the surface of the drum and the final particle size of the product was greater than 100 mm in diameter. The moisture content of this product was slightly less than its initial value. To overcome this issue, the sludge was mixed with lignite at variety ratios and then chopped before being introduced to the feeding screw. It was found that mixing the sludge with lignite and then sieving the chopped materials through a four millimetre mesh sieve was the key to solve this issue. This technique significantly reduced both stickiness and agglomeration of the material. Also, this enabled for a significant reduction in moisture content of the final product.

  5. Conversion of Agricultural Wastes to Biogas using as Inoculum Cattle Manure and Activated Sludge

    OpenAIRE

    Simina Neo; Teodor Vintilă; Marian Bura

    2012-01-01

    Agricultural wastes represent a large unexploited energy potential that could be converted into biogas by anaerobic digestion. In the present study there has been analysed the way in which agricultural wastes are converted into biogas by using as inoculum cattle manure as compared with activated sludge. To carry out this experiment on small scale there have been designed 5 batch bottles. For the batch process all substrate was put into the bottles at start. The biogas process was initiated af...

  6. Zr electrorefining process for the treatment of cladding hull waste in LiCl-KCl molten salts

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Hwa; Lee, You Lee; Jeon, Min Ku; Kang, Kweon Ho; Choi, Yong Taek; Park, Geun Il [Korea Atomic Energy Research Institute - KAERI, 989-111 Daeduk-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of)

    2013-07-01

    Zr electrorefining for the treatment of Zircaloy-4 cladding hull waste is demonstrated in LiCl-KCl-ZrCl{sub 4} molten salts. Although a Zr oxide layer thicker than 5 μm strongly inhibits the Zr dissolution process, pre-treatment processes increases the dissolution kinetics. For 10 g-scale experiments, the purities of the recovered Zr were 99.54 wt.% and 99.74 wt.% for fresh and oxidized cladding tubes, respectively, with no electrical contact issue. The optimal condition for Zr electrorefining has been found to improve the morphological feature of the recovered Zr, which reduces the salt incorporation by examining the effect of the process parameters such as the ZrCl{sub 4} concentration and the applied potential.

  7. Co-fermentation of sewage sludge and organic waste; CO-Vergaerung von Klaerschlamm und Bioabfaellen

    Energy Technology Data Exchange (ETDEWEB)

    Schmelz, K.G. [Emschergenossenschaft und Lippeverband, Essen (Germany)

    1999-07-01

    The processes taking place in sewage sludge digestion and organic waste fermentation are identical. It therefore seems obvious to treat organic waste and sewage sludge jointly. In contrast to organic waste fermentation plants to be newly erected, co-fermentation permits making use of anaerobic treatment systems that are already installed at sewage treatment plants. At these plants, in principle only the sections responsible for acceptance and conditioning of organic waste need to be retrofitted. Apart from the possibility to treat organic waste very inexpensively, the co-fermentation process offers a number of other advantages. For this reason, the Emschergenossenschaft and Lippeverband carried out extensive semi-technical scale tests in co-fermentation of organic waste and sewage sludge. (orig.) [German] Die ablaufenden biologischen Prozesse sind bei der Klaerschlammfaulung und der Bioabfallvergaerung gleich. Es liegt daher nahe, Bioabfaelle und Klaerschlaemme gemeinsam zu behandeln. Gegenueber neu zu errichtenden Bioabfall-Vergaerungsanlagen kann bei der Co-Vergaerung auf die bereits installierte Anaerobtechnik auf den Klaeranlagen zurueckgegriffen werden. Dort muss im wesentlichen nur der Annahme- und Aufbereitungsbereich fuer die Bioabfaelle nachgeruestet werden. Das Verfahren der Co-Vergaerung bietet ausser einer sehr kostenguenstigen Behandlungsmoeglichkeit fuer Bioabfaelle eine Reihe weiterer Vorteile. Aus diesem Grund wurden bei Emschergenossenschaft und Lippeverband umfangreiche halbtechnische Versuche zur Co-Vergaerung von Bioabfaellen und Klaerschlamm durchgefuehrt. (orig.)

  8. Laboratory stabilization/solidification of surrogate and actual mixed-waste sludge in glass and grout

    International Nuclear Information System (INIS)

    Grout and glass formulations were developed for the stabilization of highly radioactive tank sludges. These formulations were tested in the laboratory with a surrogate and with a sample of an actual mixed waste tank sludge. The grout formulation was tested at wet-sludge loadings of 50--60 wt%, giving a volume increase of about 40--50 vol%. Dried sludge was vitrified into glass at waste oxide loadings of 40--50 wt%, giving a volume decrease of about 50--60 vol%. The Resource Conservation and Recovery Act (RCRA) metals included in surrogate testing were Ag, Ba, Cd, Cr, Ni, Pb, Se, Tl and Hg. Since vitrification would volatilize, not stabilize mercury, it was not included in the surrogates vitrified. The actual sludge sample was only characteristically hazardous for mercury by the toxic characteristic leaching procedure (TCLP) but exceeded the Universal Treatment Standard (UTS) limit for chromium. The grout and glass formulations stabilized these RCRA metals within UTS limits. In addition, a group leachability index of about 9--10 was measured for both 85Sr and 137Cs, meeting the recommended requirement of >6. The glass leachability index was estimated to be > 18 for cold cesium and strontium

  9. Anaerobic co-digestion of waste activated sludge and greasy sludge from flotation process: Batch versus CSTR experiments to investigate optimal design

    OpenAIRE

    Girault, R.; Bridoux, G.; Nauleau, F.; Poullain, C.; Buffet, J.; Peu, P.; Sadowski, A.G.; Béline, F.

    2012-01-01

    In this study, the maximum ratio of greasy sluvdge to incorporate with waste activated sludge was investigated in batch and CSTR experiments. In batch experiments, inhibition occurred with a greasy sludge ratio of more than 20-30% of the feed COD. In CSTR experiments, the optimal greasy sludge ratio was 60% of the feed COD and inhibition occurred above a ratio of 80%. Hence, batch experiments can predict the CSTR yield when the degradation phenomenon are additive but cannot be used to determi...

  10. Towards a metagenomic understanding on enhanced biomethane production from waste activated sludge after pH 10 pretreatment

    OpenAIRE

    Wong, Mabel Ting; Zhang, Dong; Jun LI; Hui, Raymond Kin Hi; Tun, Hein Min; Brar, Manreetpal Singh; Park, Tae-Jin; Chen, Yinguang; Leung, Frederick C.

    2013-01-01

    BACKGROUND: Understanding the effects of pretreatment on anaerobic digestion of sludge waste from wastewater treatment plants is becoming increasingly important, as impetus moves towards the utilization of sludge for renewable energy production. Although the field of sludge pretreatment has progressed significantly over the past decade, critical questions concerning the underlying microbial interactions remain unanswered. In this study, a metagenomic approach was adopted to investigate the mi...

  11. The influence of amendment material on biosolid composting of sludge from a waste-water treatment plant

    Directory of Open Access Journals (Sweden)

    Patricia Torres Lozada

    2010-06-01

    Full Text Available Aerobic composting employing manual turning was evaluated by using the sludge produced by EMCALI EICE ESP's Cañaverlejo wastewater treatment plant (PTAR-C. Compost (in 1,0 ton piles consisted of sludge, a fixed proportion of bulking agent (10% and amendment material. Sugarcane waste and solid organic (marketplace waste were evaluated as amendment material using 20/80 and 40/60 weight/weight (amendment/sludge ratios. Incorporating the amendment material improved the compost, being reflected in a faster start for the thermophilic phase, higher temperatures beign maintained (>55°C and better C/N ratio obtained in the compost in all treatments compared to the pile which had no amendment added to it. Incorporating the bulking agent improved sludge manageability during composting; the best combination was 54% sludge + 10% sugacane bagasse + 36% liquid sugarcane waste.

  12. CO-DIGESTION OF CULTIVATED MICROALGAE AND SEWAGE SLUDGE FROM MUNICIPAL WASTE WATER TREATMENT

    OpenAIRE

    Olsson, Jesper; Ma, Shabiimam; Nehrenheim, Emma; Thorin, Eva

    2013-01-01

    The demand for biogas is continuously growing and the biogas substrate, such as food waste, may soon become limited and it is therefore important for biogas producers to expand the range of substrates. One way can be to use microalgae in co-digestion with sewage sludge. The present study explores the possibilities to use harvested microalgae from Lake Mälaren, as a co-substrate to sewage sludge in biogas production under mesophilic and thermophilic conditions. The aim is to investigate if co...

  13. Characteristics of lagoon sludge waste generated from an uranium conversion plant

    International Nuclear Information System (INIS)

    The Korea Atomic Energy Research Institute (KAERI) has launched a decommissioning program of the uranium conversion plant. The sludge waste, which was generated during the operation of the plant and stored in the lagoon, was characterized for the development of the treatment process. The physical properties were measured and chemical compositions and radiological properties analyzed. The main compounds of the sludge were ammonium nitrate, sodium nitrate, calcium nitrate, and calcium carbonate. All heavy radioactive elements such as uranium, thorium and 226Ra were precipitated and deposited at the bottom, and were not dissolved in the concentrated nitrate solution. A possible flow-scheme for processing is presented. (author)

  14. Hazard Evaluation for Storage of Spent Nuclear Fuel (SNF) Sludge at the Solid Waste Treatment Facility

    International Nuclear Information System (INIS)

    This document describes the hazards and operability (HAZOP) analysis performed for the activities associated with the storage of Spent Nuclear Fuel (SNF) sludge at the T Plant. The safety authorization basis for the T Plant for SNF sludge storage is defined as those aspects of facility design and operational requirements relied upon by DOE to authorize operations. The safety authorization basis for the current T Plant activities is described in HNF-SD-WM-ISB-006, Rev 2, ''Interim Safety Basis for Solid Waste Facilities (T Plant) (ISB)'' and associated amendments and engineering change notices. In addition the authorization basis includes other document as summarized in Section 1.3

  15. OPERATIONAL CHALLENGES IN MIXING AND TRANSFER OF HIGH YIELD STRESS SLUDGE WASTE

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, T.; Bhatt, P.

    2009-12-07

    The ability to mobilize and transport non-Newtonian waste is essential to advance the closure of highly radioactive storage tanks. Recent waste removal operations from Tank 12H at the Savannah River Site (SRS) encountered sludge mixtures with a yield stress too high to pump. The waste removal equipment for Tank 12H was designed to mobilize and transport a diluted slurry mixture through an underground 550m long (1800 ft) 0.075m diameter (3 inch) pipeline. The transfer pump was positioned in a well casing submerged in the sludge slurry. The design allowed for mobilized sludge to enter the pump suction while keeping out larger tank debris. Data from a similar tank with known rheological properties were used to size the equipment. However, after installation and startup, field data from Tank 12H confirmed the yield stress of the slurry to exceed 40 Pa, whereas the system is designed for 10 Pa. A revision to the removal strategy was required, which involved metered dilution, blending, and mixing to ensure effective and safe transfer performance. The strategy resulted in the removal of over 255,000 kgs of insoluble solids with four discrete transfer evolutions for a total transfer volume of 2400 m{sup 3} (634,000 gallons) of sludge slurry.

  16. Operational Challenges In Mixing And Transfer Of High Yield Stress Sludge Waste

    International Nuclear Information System (INIS)

    The ability to mobilize and transport non-Newtonian waste is essential to advance the closure of highly radioactive storage tanks. Recent waste removal operations from Tank 12H at the Savannah River Site (SRS) encountered sludge mixtures with a yield stress too high to pump. The waste removal equipment for Tank 12H was designed to mobilize and transport a diluted slurry mixture through an underground 550m long (1800 ft) 0.075m diameter (3 inch) pipeline. The transfer pump was positioned in a well casing submerged in the sludge slurry. The design allowed for mobilized sludge to enter the pump suction while keeping out larger tank debris. Data from a similar tank with known rheological properties were used to size the equipment. However, after installation and startup, field data from Tank 12H confirmed the yield stress of the slurry to exceed 40 Pa, whereas the system is designed for 10 Pa. A revision to the removal strategy was required, which involved metered dilution, blending, and mixing to ensure effective and safe transfer performance. The strategy resulted in the removal of over 255,000 kgs of insoluble solids with four discrete transfer evolutions for a total transfer volume of 2400 m3 (634,000 gallons) of sludge slurry.

  17. Thermogravimetric analysis of the co-pyrolysis of paper sludge and municipal solid waste

    International Nuclear Information System (INIS)

    Highlights: • The co-pyrolysis of municipal solid waste, paper sludge and the blends was studied. • The reactivity of paper sludge could be improved by blending municipal solid waste. • The FWO and KAS methods were used to calculate activation energy. • The average activation energy was the minimum by blending 50% paper sludge. - Abstract: The pyrolysis characteristics of municipal solid waste (MSW), paper sludge (PS) and their blends were studied through a thermogravimetric simultaneous thermal analyzer from room temperature to 1000 °C. Meanwhile their kinetics were studied by Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) methods. The mass proportions of PS in the blends were 10%, 30%, 50%, 70%, 90%, respectively and the experiments were carried out at different heating rates (30, 40 and 50 °C/min). The initial temperature of MSW was lower than that of PS and the terminated temperature was higher than PS. The comprehensive characteristic index decreased progressively along with the decrease of the MSW proportion. The values of average activation energies calculated by FWO and KAS methods were highly consistent. The average activation energy reached the minimum number, 96.7 kJ/mol by KAS and 11.56 kJ/mol by FWO, with the proportion of PS was 50%

  18. Reprocessing of zinc galvanic waste sludge by selective precipitation

    Czech Academy of Sciences Publication Activity Database

    Jandová, J.; Maixner, J.; Grygar, Tomáš

    2002-01-01

    Roč. 46, č. 2 (2002), s. 52-55. ISSN 0862-5468 R&D Projects: GA AV ČR IBS4032004; GA ČR GA203/99/0067 Institutional research plan: CEZ:AV0Z4032918; CEZ:MSM 223100002 Keywords : galvanic sludge * recovery * zinc Subject RIV: CA - Inorganic Chemistry Impact factor: 0.354, year: 2002

  19. Irradiated Palm Oil Waste (Sludge) As Feed Supplement For Nila Gift Fish (Oreochromis niloticus)

    International Nuclear Information System (INIS)

    The objective of the experiment was to study the fish weight development after being fed with irradiated palm oil waste pellet. Irradiated Palm oil waste pellet was produced from palm oil waste (sludge) with some additional materials, i.e. rice bran, fish powder, soybean powder, tapioca powder. The mixture was then irradiated with a dose of 4 kGy to decontaminate pathogen microbe and other contaminant microbes, the experiment have been carried out in 4 treatments. Treatment A was male fish which was being fed with irradiated sludge palm oil waste pellet and commercial pelletized feed (2:1), treatment C was female with the same feed as A, treatment B was male fish feed with commercial pelletized, treatment D was female fish with the same feed as B. Each treatment was placed in a pond. The feed with the amount of 3% of total body weight was given to the fishes 2 times per day. The result of this experiment showed that the male fish weight receiving treatment A and B were 195.37 g and 175.12 g. The female fish weight at treatments C and D were 170.28 g and 160.15 g, respectively. Data obtained from this experiment showed that the treatment of irradiated sludge palm oil waste pellet and commercial pelletized (2:1) were more efficient as fish feeding compared to commercial pellets

  20. Food waste co-digestion with sewage sludge--realising its potential in the UK.

    Science.gov (United States)

    Iacovidou, Eleni; Ohandja, Dieudonné-Guy; Voulvoulis, Nikolaos

    2012-12-15

    The application of anaerobic co-digestion of food waste with sewage sludge, although well established in many European countries, is still in its infancy in the UK. This process has many benefits to offer, with a successful application often associated with increased renewable energy potential, outweighing constraints associated with the variability of food waste and its handling requirements prior to co-digestion. With both regulations and water infrastructures designed and constructed on the basis of linear views and sectorial requirements and conditions and technologies from the past in many parts of the world, in the UK, sewage sludge and food waste digestion operations are also under very different regulatory and management regimes. With sustainability requiring that we do not address single issues in isolation, but through a systems approach that delivers integrated solutions, co-digestion of food waste with sewage sludge could become such a solution. If carefully applied, co-digestion can deliver beneficial synergies for the water industry and authorities responsible for food waste management. The collaboration of all relevant stakeholders and regulators to support changes to current regulatory frameworks to enable this, is proposed as the way forward, particularly as their complexity has been identified as the major hurdle to the implementation of co-digestion in the UK. PMID:22940124

  1. Comparative evaluation of anaerobic digestion for sewage sludge and various organic wastes with simple modeling.

    Science.gov (United States)

    Hidaka, Taira; Wang, Feng; Tsumori, Jun

    2015-09-01

    Anaerobic co-digestion of sewage sludge and other organic wastes, such as kitchen garbage, food waste, and agricultural waste, at a wastewater treatment plant (WWTP) is a promising method for both energy and material recovery. Substrate characteristics and the anaerobic digestion performance of sewage sludge and various organic wastes were compared using experiments and modeling. Co-digestion improved the value of digested sewage sludge as a fertilizer. The relationship between total and soluble elemental concentrations was correlated with the periodic table: most Na and K (alkali metals) were soluble, and around 20-40% of Mg and around 10-20% of Ca (alkaline earth metals) were soluble. The ratio of biodegradable chemical oxygen demand of organic wastes was 65-90%. The methane conversion ratio and methane production rate under mesophilic conditions were evaluated using a simplified mathematical model. There was reasonably close agreement between the model simulations and the experimental results in terms of methane production and nitrogen concentration. These results provide valuable information and indicate that the model can be used as a pre-evaluation tool to facilitate the introduction of co-digestion at WWTPs. PMID:26031329

  2. Treatment of the oily waste sludges through thermal plasma in absence of oxygen

    International Nuclear Information System (INIS)

    The thermal plasma process in absence of oxygen for the degradation of oily waste sludges was evaluated. These residues are commonly generated in the petrochemical industry and are considered hazardous wastes according to the present environmental regulations. The process was operated using difference residence times and the characteristics of the gaseous by products and residual soils were determined. The efficiency of organic matter degradation was 99.99%. The attained volume reduction, under the best conditions was 95.5%. The residual soils were composed of carbon and clays. The residual gases have low molecular weight. The resulting final wastes were non-hazardous and could be disposed of in landfills. (Author)

  3. Treatment of the oily waste sludges through thermal plasma in absence of oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda J, G.; Pacheco S, J. [Instituto Nacional de Investigaciones Nucleares. Laboratorio de Aplicaciones de Plasmas Termicos. Apdo. Postal 18-1027. C.P. 11801 Mexico D.F. (Mexico)

    2001-07-01

    The thermal plasma process in absence of oxygen for the degradation of oily waste sludges was evaluated. These residues are commonly generated in the petrochemical industry and are considered hazardous wastes according to the present environmental regulations. The process was operated using difference residence times and the characteristics of the gaseous by products and residual soils were determined. The efficiency of organic matter degradation was 99.99%. The attained volume reduction, under the best conditions was 95.5%. The residual soils were composed of carbon and clays. The residual gases have low molecular weight. The resulting final wastes were non-hazardous and could be disposed of in landfills. (Author)

  4. Final disposal of dissolver sludges, claddings, fuel hardware, and spent HTGR fuel elements in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    In the Federal Republic of Germany, radioactive waste of marked decay heat production shall be disposed of in vertical 300-m-deep boreholes in a salt dome formation. The disposal technique for heat generating intermediate-level wastes arising from LWR fuel reprocessing and for spent HTGR pebble bed fuel is referred to as the ILW borehole technique. This technique is under development since 1983 in a R and D project for intermediate-level waste and spent HTGR fuel element test disposal in boreholes. This paper reports on the main objectives of this project, to establish the ILW borehole technique by developing the emplacement and plugging concept up to design and testing of prototype components and testing of the multicomponent technique under real conditions in the ASSE salt mine

  5. Effect of Pretreating Waste Activated Sludge with Ozone on the Performance of Aerobic Digestion Process

    Directory of Open Access Journals (Sweden)

    H Asilian

    2009-03-01

    Full Text Available "n "nBackground and Objectives: A conventional treatment to stabilize the excess activated sludge is the aerobic digestion process but due to long aeration time, it requires large equipments as well as high investment cost. Because of high oxidation potential of ozone, sludge ozonation enhances stabilization rate and reduces sludge treatment equipment size and cost. Therefore, in this study, the combination of pretreatment with ozone and aerobic digestion processes were investigated."nMaterials and Methods: The experimental set-up consisted of an ozone generator and ozonation reactor with the total volume of 2 L. Removal percentages of TSS, VS, total and soluble COD, HPC, fecal coliform and settable solids were measured in integrated process compared to the single ones."nResults: The results of this research indicated that the aerobic digestion of waste activated sludge during 10 days could reduce 38% of volatile solids and thus obtaining the EPA standard. Also, the results of combined ozonation and aerobic digestion revealed that the pre-ozonation at 0.25 g O3/g TS or 0.5 g O3/g TS with 6 or 3 days aeration, respectively, could achieve 38% reduction in VS and hence the requirement set by EPA. Therefore, integration of pre-ozonation with aerobic digestion can significantly reduce the digestion time to attain the standards."nConclusion: The sludge pre-ozonation with low dose of ozone due to solids disintegration can enhance the efficiency of aerobic digestion in waste activated sludge stabilization, and consequently decrease size of equipments, air requirement, investment and probably operation cost.

  6. Enhanced waste activated sludge digestion using a submerged anaerobic dynamic membrane bioreactor: performance, sludge characteristics and microbial community

    Science.gov (United States)

    Yu, Hongguang; Wang, Zhiwei; Wu, Zhichao; Zhu, Chaowei

    2016-02-01

    Anaerobic digestion (AD) plays an important role in waste activated sludge (WAS) treatment; however, conventional AD (CAD) process needs substantial improvements, especially for the treatment of WAS with low solids content and poor anaerobic biodegradability. Herein, we propose a submerged anaerobic dynamic membrane bioreactor (AnDMBR) for simultaneous WAS thickening and digestion without any pretreatment. During the long-term operation, the AnDMBR exhibited an enhanced sludge reduction and improved methane production over CAD process. Moreover, the biogas generated in the AnDMBR contained higher methane content than CAD process. Stable carbon isotopic signatures elucidated the occurrence of combined methanogenic pathways in the AnDMBR process, in which hydrogenotrophic methanogenic pathway made a larger contribution to the total methane production. It was also found that organic matter degradation was enhanced in the AnDMBR, thus providing more favorable substrates for microorganisms. Pyrosequencing revealed that Proteobacteria and Bacteroidetes were abundant in bacterial communities and Methanosarcina and Methanosaeta in archaeal communities, which played an important role in the AnDMBR system. This study shed light on the enhanced digestion of WAS using AnDMBR technology.

  7. Effect of polyhydroxyalkanoates on dark fermentative hydrogen production from waste activated sludge.

    Science.gov (United States)

    Wang, Dongbo; Zeng, Guangming; Chen, Yinguang; Li, Xiaoming

    2015-04-15

    Polyhydroxyalkanoates (PHA), an intracellular energy and carbon storage polymer, can be accumulated in activated sludge in substantial quantities under wastewater dynamic treatment (i.e., substrate feast-famine) conditions. However, its influence on hydrogen production has never been investigated before. This study therefore evaluated the influences of PHA level and composition in waste activated sludge (WAS) on hydrogen production. The results showed that with the increase of sludge PHA content from 25 to 178 mg per gram volatile suspended solids (VSS) hydrogen production from WAS alkaline anaerobic fermentation increased from 26.5 to 58.7 mL/g VSS. The composition of PHA was also found to affect hydrogen production. When the dominant composition shifted from polyhydroxybutyrate (PHB) to polyhydroxyvalerate (PHV), the amount of generated hydrogen decreased from 51.2 to 41.1 mL/g VSS even under the same PHA level (around 130 mg/g VSS). The mechanism studies exhibited that the increased PHA content accelerated both the cell solubilization and the hydrolysis process of solubilized substrates. Compared with the PHB-dominant sludge, the increased PHV fraction not only slowed the hydrolysis process but also caused more propionic acid production, with less theoretical hydrogen generation in this fermentation type. It was also found that the increased PHA content enhanced the soluble protein conversion of non-PHA biomass. Further investigations with enzyme analyses showed that both the key hydrolytic enzyme activities and hydrogen-forming enzyme activities were in the sequence of the PHB-dominant sludge > the PHV-dominant sludge > the low PHA sludge, which was in accord with the observed order of hydrogen yield. PMID:25697693

  8. Enhancing anaerobic digestion of waste activated sludge by pretreatment: effect of volatile to total solids.

    Science.gov (United States)

    Wang, Xiao; Duan, Xu; Chen, Jianguang; Fang, Kuo; Feng, Leiyu; Yan, Yuanyuan; Zhou, Qi

    2016-06-01

    In this study the effect of volatile to total solids (VS/TS) on anaerobic digestion of waste activated sludge (WAS) pretreated by alkaline, thermal and thermal-alkaline strategies was studied. Experimental results showed that the production of methane from sludge was increased with VS/TS. When anaerobic digesters were fed with sludge pretreated by the thermal-alkaline method, the average methane yield was improved from 2.8 L/d at VS/TS 0.35 to 4.7 L/d at VS/TS 0.56. Also, the efficiency of VS reduction during sludge anaerobic digestion varied between 18.9% and 45.6%, and increased gradually with VS/TS. Mechanism investigation of VS/TS on WAS anaerobic digestion suggested that the general activities of anaerobic microorganisms, activities of key enzymes related to sludge hydrolysis, acidification and methanogenesis, and the ratio of Archaea to Bacteria were all increased with VS/TS, showing good agreement with methane production. PMID:26698921

  9. Photovoltaic's silica-rich waste sludge as supplementary cementitious material (SCM)

    International Nuclear Information System (INIS)

    Waste sludge, a solid recovered from wastewater of photovoltaic-industries, composes of agglomerates of nano-particles like SiO2 and CaCO3. This sludge deflocculates in aqueous solutions into nano-particles smaller than 1 μm. Thus, this sludge constitutes a potentially hazardous waste when it is improperly disposed. Due to its high content of amorphous SiO2, this sludge has a potential use as supplementary cementitious material (SCM) in concrete. In this study the main properties of three different samples of photovoltaic's silica-rich waste sludge (nSS) were physically and chemically characterized. The characterization techniques included: scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), nitrogen physical adsorption isotherm (BET method), density by Helium pycnometry, particle size distribution determined by laser light scattering (LLS) and zeta-potential measurements by dynamic light scattering (DLS). In addition, a dispersability study was performed to design stable slurries to be used as liquid additives for the concrete production on site. The effects on the hydration kinetics of cement pastes by the incorporation of nSS in the designed slurries were determined using an isothermal calorimeter. A compressive strength test of standard mortars with 7% of cement replacement was performed to determine the pozzolanic activity of the waste nano-silica sludge. Finally, the hardened system was fully characterized to determine the phase composition. The results demonstrate that the nSS can be utilized as SCM to replace portion of cement in mortars, thereby decreasing the CO2 footprint and the environmental impact of concrete. -- Highlights: •Three different samples of PV nano-silica sludge (nSS) were fully characterized. •nSS is composed of agglomerates of nano-particles like SiO2 and CaCO3. •Dispersability studies demonstrated that nSS agglomerates are broken to nano-size. •nSS can be classified as a

  10. Recovery of Organic and Amino Acids from Sludge and Fish Waste in Sub Critical Water Conditions

    Directory of Open Access Journals (Sweden)

    Muhammad Faisal

    2011-12-01

    Full Text Available The possibility of organic and amino acid production from the treatment of sludge and fish waste using water at sub critical conditions was investigated. The results indicated that at sub-critical conditions, where the ion product of water went through a maximum, the formation of organic acids was favorable. The presence of oxidant favored formation of acetic and formic acid. Other organic acids of significant amount were propionic, succinic and lactic acids. Depending on the type of wastes, formation of other organic acids was also possible. Knowing the organic acids obtained by hydrolysis and oxidation in sub-critical water of various wastes are useful in designing of applicable waste treatment process, complete degradation of organic wastes into volatile carbon and water, and also on the viewpoint of resource recovery. The production of lactic acid was discussed as well. The results indicated that temperature of 573 K, with the absence of oxidant, yield of lactic acid from fish waste was higher than sewage sludge. The maximum yield of total amino acids (137 mg/g-dry fish from waste fish entrails was obtained at subcritical condition (T = 523 K, P = 4 MPa at reaction time of 60 min by using the batch reactor. The amino acids obtained in this study were mainly alanine and glycine. Keywords:  organic acids, amino acids, sub-critical water, hydrothermal, resources recovery

  11. Ultrasonic techniques for the in situ characterisation of 'legacy' Waste sludges and dispersions - 59111

    International Nuclear Information System (INIS)

    Research being undertaken at the University of Leeds, as part of the DIAMOND university consortium, is exploring the effectiveness of various ultrasonic technologies as in situ probes to characterize and monitor nuclear waste slurries, such as the 'Legacy' Magnesium hydroxide sludges found in Sellafield, U.K. Through use of a commercial Acoustic Backscatter Sensor (ABS) with 1 - 5 MHz transducers, various properties of free-settling oxide simulant sludges were determined. Work was focused upon characterizing essentially 'static' sludges (to give prospective use as tools for the wastes in current deposits); although, the sensors also have potential as dispersion monitors during any future processing and storage of the Legacy wastes, as well as many other storage, clarifier or thickener systems across a wide range of industrial processing operations. ABS data of mixed glass powder dispersions was analysed and compared to scattering theory, to understand the correlations between acoustic attenuation and particulate concentration. The ABS was also calibrated to measure changes in average particulate concentration within a settling suspension over time, and showed the depth-wise segregation of the dispersion through the settling column at different particular time intervals. It was found that observed hindered settling also led to an increase in particulate concentration over the sludge zone and significant segregation occurred at moderate time intervals, due to the broad size distribution of the aggregates measured. It is hoped in future that these sensors may be able to be fitted to robotic handlers that have been installed onsite (and previously used for sampling), allowing fully automatic in situ sludge analysis. (authors)

  12. Characterization Of Actinides In Simulated Alkaline Tank Waste Sludges And Leachates

    International Nuclear Information System (INIS)

    In this project, both the fundamental chemistry of actinides in alkaline solutions (relevant to those present in Hanford-style waste storage tanks), and their dissolution from sludge simulants (and interactions with supernatants) have been investigated under representative sludge leaching procedures. The leaching protocols were designed to go beyond conventional alkaline sludge leaching limits, including the application of acidic leachants, oxidants and complexing agents. The simulant leaching studies confirm in most cases the basic premise that actinides will remain in the sludge during leaching with 2-3 M NaOH caustic leach solutions. However, they also confirm significant chances for increased mobility of actinides under oxidative leaching conditions. Thermodynamic data generated improves the general level of experiemental information available to predict actinide speciation in leach solutions. Additional information indicates that improved Al removal can be achieved with even dilute acid leaching and that acidic Al(NO3)3 solutions can be decontaminated of co-mobilized actinides using conventional separations methods. Both complexing agents and acidic leaching solutions have significant potential to improve the effectiveness of conventional alkaline leaching protocols. The prime objective of this program was to provide adequate insight into actinide behavior under these conditions to enable prudent decision making as tank waste treatment protocols develop.

  13. CHARACTERIZATION OF ACTINIDES IN SIMULATED ALKALINE TANK WASTE SLUDGES AND LEACHATES

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Kenneth L.

    2008-11-20

    In this project, both the fundamental chemistry of actinides in alkaline solutions (relevant to those present in Hanford-style waste storage tanks), and their dissolution from sludge simulants (and interactions with supernatants) have been investigated under representative sludge leaching procedures. The leaching protocols were designed to go beyond conventional alkaline sludge leaching limits, including the application of acidic leachants, oxidants and complexing agents. The simulant leaching studies confirm in most cases the basic premise that actinides will remain in the sludge during leaching with 2-3 M NaOH caustic leach solutions. However, they also confirm significant chances for increased mobility of actinides under oxidative leaching conditions. Thermodynamic data generated improves the general level of experiemental information available to predict actinide speciation in leach solutions. Additional information indicates that improved Al removal can be achieved with even dilute acid leaching and that acidic Al(NO3)3 solutions can be decontaminated of co-mobilized actinides using conventional separations methods. Both complexing agents and acidic leaching solutions have significant potential to improve the effectiveness of conventional alkaline leaching protocols. The prime objective of this program was to provide adequate insight into actinide behavior under these conditions to enable prudent decision making as tank waste treatment protocols develop.

  14. Effects of ozonation on disinfection and microbial activity in waste activated sludge for land application

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Kyu-Hong; Maeng, Sung Kyu; Hong, Jun-Seok; Lim, Byung-Ran

    2003-07-01

    Effects of ozonation on microbial biomass activity and community structure in waste activated sludges from various treatment plants were investigated. The densities of viable cells and microbial community structure in the sludges treated with ozone at 0.1, 0.2 and 0.4 gO{sub 3}/gDS were measured on the basis of the respiratory quinone profile and LIVE/DEAD Backlight(TM). The results from the bacterial concentration and quinone profiles of the waste activated sludge showed that respiratory activities of microorganisms were detected at the ozone dose of 0.4 gO{sub 3}/gDS. However, fecal coliform, fecal streptococcus and Salmonella sp. in the ozonized sludge were not detected. This result implies that some microorganisms might be more tolerant to ozonation than the pathogenic indicators. The pathogens reduction requirements for Class A biosolids were still met by the ozonation at 0.4 gO{sub 3}/gDS.

  15. Co-digestion of municipal sludge and external organic wastes for enhanced biogas production under realistic plant constraints.

    Science.gov (United States)

    Tandukar, Madan; Pavlostathis, Spyros G

    2015-12-15

    A bench-scale investigation was conducted to select external organic wastes and mixing ratios for co-digestion with municipal sludge at the F. Wayne Hill Water Resources Center (FWHWRC), Gwinnett County, GA, USA to support a combined heat and power (CHP) project. External wastes were chosen and used subject to two constraints: a) digester retention time no lower than 15 d; and b) total biogas (methane) production not to exceed a specific target level based on air permit constraints on CO2 emissions. Primary sludge (PS), thickened waste activated sludge (TWAS) and digested sludge collected at the FWHWRC, industrial liquid waste obtained from a chewing gum manufacturing plant (GW) and dewatered fat-oil-grease (FOG) were used. All sludge and waste samples were characterized and their ultimate digestibility was assessed at 35 °C. The ultimate COD to methane conversion of PS, TWAS, municipal sludge (PS + TWAS; 40:60 w/w TS basis), GW and FOG was 49.2, 35.2, 40.3, 72.7, and 81.1%, respectively. Co-digestion of municipal sludge with GW, FOG or both, was evaluated using four bench-scale, mesophilic (35 °C) digesters. Biogas production increased significantly and additional degradation of the municipal sludge between 1.1 and 30.7% was observed. Biogas and methane production was very close to the target levels necessary to close the energy deficit at the FWHWRC. Co-digestion resulted in an effluent quality similar to that of the control digester fed only with the municipal sludge, indicating that co-digestion had no adverse effects. Study results prove that high methane production is achievable with the addition of concentrated external organic wastes to municipal digesters, at acceptable higher digester organic loadings and lower retention times, allowing the effective implementation of CHP programs at municipal wastewater treatment plants, with significant cost savings. PMID:25979784

  16. "Isolation and Identification of Bacteria Present in the Activated Sludge Unit, in the Treatment of Industrial Waste Water "

    Directory of Open Access Journals (Sweden)

    MK Sharifi-Yazdi1

    2001-09-01

    Full Text Available Activated sludge or extended aeration treatment involves a continous system where aerobic biological growths are mixed with waste water and then separated in a gravity clarifier. Therefore, waste treatment system such as the activated sludge system depend on the activities of communities of living organism. In this study, an attempt was made on the indentification of the bacterial population involved in the laboratory activated sludge unit. The results showed that gram-negative bacilli with a yellow pigment was considered as a major group of the population.

  17. Leachability of Heavy Metals from Lightweight Aggregates Made with Sewage Sludge and Municipal Solid Waste Incineration Fly Ash

    OpenAIRE

    Na Wei

    2015-01-01

    Lightweight aggregate (LWA) production with sewage sludge and municipal solid waste incineration (MSWI) fly ash is an effective approach for waste disposal. This study investigated the stability of heavy metals in LWA made from sewage sludge and MSWI fly ash. Leaching tests were conducted to find out the effects of MSWI fly ash/sewage sludge (MSWI FA/SS) ratio, sintering temperature and sintering time. It was found that with the increase of MSWI FA/SS ratio, leaching rates of all heavy metal...

  18. Control of environmental pollution by using treated solid sludge waste as soil amendment

    International Nuclear Information System (INIS)

    The disposal of industrial waste is very significant problem that appears as an integral part of industrial development. This problem is equally signified in developed and developing countries. Solid waste and effluents are of particular importance and a prominent threat to environment. Crescent Bahuman Limited (CBL) is a textile industry operating near Pindi Bhattian, Pakistan and producing 26000 denim/day. Along with other wastes, the industry is facing problem of disposal of 130 T/month of treated solid sludge that is piling up consistently. This material contains organic matter, N, P and K and some micronutrients coming from cotton waste and household. Due to its present constituents it could be a useful source for reclamation and subsequent enhancement of fertility of sodic soils. This study was conducted to thrash out such possibilities. Treated solid sludge was used as an amendment alone or in combination with gypsum or sulphuric acid as well as compared with gypsum alone or gypsum+ sulphuric acid in addition to control. Data indicated that combination of treated sludge with gypsum or sulphuric acid proved most successful in rehabilitation of sodic soil (EC=2.56 d S/m SAR= 38.89 and pH= 10.1 Texture= sandy clay loam) as SAR and pH decreased significantly and brought within permissible limits after the growth of subsequent two crops. The yield of rice and wheat also increased significantly. Treated sludge alone proved superior to gypsum alone due to plant nutrients contained in it but both were statistically better than control (where no amendment was added). The soil fertility parameters (Organic matter, phosphorus and potassium) were also improved appreciably as compared to control. (author)

  19. Ammonia-methane two-stage anaerobic digestion of dehydrated waste-activated sludge

    OpenAIRE

    Nakashimada, Yutaka; Ohshima, Yasutaka; Minami, Hisao; Yabu, Hironori; Namba,Yuzaburo; Nishio, Naomichi

    2008-01-01

    In repeated batch-wise thermophilic anaerobic digestion of dehydrated waste-activated sludge with 80% (w/w) water content (DWAS), although methane production reached 30 % of total organic carbon in DWAS in the first run of 15d, it gradually decreased and finally stopped in the subsequent runs together with an increase in ammonia concentration. When the loading of DWAS on anaerobic digestion was investigated, methane production at 30d significantly decreased with the increase in the amount of ...

  20. Modeling and Production of Bioethanol from Mixtures of Cotton Gin Waste and Recycled Paper Sludge

    OpenAIRE

    Shen, Jiacheng

    2008-01-01

    In this study, the hydrolytic kinetics of mixtures of cotton gin waste (CGW) and recycled paper sludge (RPS) at various initial enzyme concentrations of Spezyme AO3117 and Novozymes NS50052 was investigated. The experiments showed that the concentrations of reducing sugars and the conversions of the mixtures increased with increasing initial enzyme concentration. The reducing sugar concentration and conversion of the mixture of 75% CGW and 25% RPS were higher than those of the mixture of 80% ...

  1. Spectroscopic characterization of digestates obtained from sludge mixed to increasing amounts of fruit and vegetable wastes

    Science.gov (United States)

    Provenzano, Maria Rosaria; Cavallo, Ornella; Malerba, Anna Daniela; Di Maria, Francesco; Ricci, Anna; Gigliotti, Giovanni

    2015-04-01

    Anaerobic digestion (AD) represents an efficient waste-treatment technology during which microorganisms break down biodegradable material in absence of oxygen yielding a biogas containing methane. The aim of this work was to investigate the transformations occurring in the organic matter during the co-digestion of waste mixed sludge (WMS) with an increasing amount of fruit and vegetable wastes (FVW) in a pilot scale apparatus reproducing a full-scale digester in an existing wastewater treatment plant. Samples comprised: sludge, FVW, sludge mixed with 10-20-30-40% FVW. Ingestates and digestates were analyzed by means of emission fluorescence spectroscopy and FTIR associated to Fourier self deconvolution (FSD) of spectra. With increasing the amount of FVW from 10% to 20% at which percentage biogas production reached the maximum value, FTIR spectra and FSD traces of digestates exhibited a decrease of intensity of peaks assigned to polysaccharides and aliphatics and an increase of peak assigned to aromatics as a result of the biodegradation of rapidly degradable materials and concentration of aromatic recalcitrant compounds. Digestates with 30 and 40% FVW exhibited a relative increase of intensity of peaks assigned to aliphatics likely as a result of the increasing amount of rapidly degradable materials and the consequent reduction of the hydraulic retention time. This may cause inhibition of methanogenesis and accumulation of volatile fatty acids. The highest emission fluorescence intensity was observed for the digestate with 20% FVW confirming the concentration of aromatic recalcitrant compounds in the substrate obtained at the highest biogas production.

  2. Utilization of molasses spentwash for production of bioplastics by waste activated sludge

    International Nuclear Information System (INIS)

    Present study describes the treatment of molasses spentwash and its use as a potential low cost substrate for production of biopolymer polyhydroxybutyrate (PHB) by waste activated sludge. Fluorescence microscopy revealed the presence of PHB granules in sludge biomass which was further confirmed by fourier transform-infra-red spectroscopy (FT-IR) and 13C nuclear magnetic resonance (NMR). The processing of molasses spentwash was carried out for attaining different ratios of carbon and nitrogen (C:N). Highest chemical oxygen demand (COD) removal and PHB accumulation of 60% and 31% respectively was achieved with raw molasses spentwash containing inorganic nitrogen (C:N ratio = 28) followed by COD removal of 52% and PHB accumulation of 28% for filtered molasses containing inorganic nitrogen (C:N ratio = 29). PHB production yield (Yp/s) was highest (0.184 g g-1 COD consumed) for deproteinized spentwash supplemented with nitrogen. In contrast, the substrate consumption and product formation were higher in case of raw spentwash. Though COD removal was lowest from deproteinized spentwash, evaluation of kinetic parameters suggested higher rates of conversion of available carbon to biomass and PHB. Thus the process provided dual benefit of conversion of two wastes viz. waste activated sludge and molasses spentwash into value-added product-PHB.

  3. Optimisation of bio methane production admixing organic fraction of municipal solid waste and sewage sludge

    International Nuclear Information System (INIS)

    Optimisation of bio methane production was carried out using the co-blended organic fraction of municipal solid waste (OFMSW) and sewage sludge (SS). The co-blending was evaluated at a range of carbon to nitrogen ratios (C:N) using a standard biochemical methane potential (BMP) test. OFMSW has a very high C:N ratio of around 30 and is predominantly carbon whereas by contrast, waste activated sludge has a low ratio of around 4.9 and comprises nitrogen. Co-blending of OFMSW with the thickened sludge from wastewater increases both the amount and the methane produced during anaerobic digestion. The optimum blend occurs at a C:N ratio of 15 which is achieved with 30% of organic fraction of municipal solid waste. The highest methane yield of 161 mL/g VS removed was also observed at C:N 15. The highest destruction of volatile solids of 85% was achieved at C:N of 20 followed by C:N 30 and 15. No inhibition was observed by ammonia at any C:N ratio's. (author)

  4. Revised cost savings estimate with uncertainty for enhanced sludge washing of underground storage tank waste

    International Nuclear Information System (INIS)

    Enhanced Sludge Washing (ESW) has been selected to reduce the amount of sludge-based underground storage tank (UST) high-level waste at the Hanford site. During the past several years, studies have been conducted to determine the cost savings derived from the implementation of ESW. The tank waste inventory and ESW performance continues to be revised as characterization and development efforts advance. This study provides a new cost savings estimate based upon the most recent inventory and ESW performance revisions, and includes an estimate of the associated cost uncertainty. Whereas the author's previous cost savings estimates for ESW were compared against no sludge washing, this study assumes the baseline to be simple water washing which more accurately reflects the retrieval activity along. The revised ESW cost savings estimate for all UST waste at Hanford is $6.1 B ± $1.3 B within 95% confidence. This is based upon capital and operating cost savings, but does not include development costs. The development costs are assumed negligible since they should be at least an order of magnitude less than the savings. The overall cost savings uncertainty was derived from process performance uncertainties and baseline remediation cost uncertainties, as determined by the author's engineering judgment

  5. A novel approach for phosphorus recovery and no wasted sludge in enhanced biological phosphorus removal process with external COD addition.

    Science.gov (United States)

    Xia, Cheng-Wang; Ma, Yun-Jie; Zhang, Fang; Lu, Yong-Ze; Zeng, Raymond J

    2014-01-01

    In enhanced biological phosphorus removal (EBPR) process, phosphorus (P) in wastewater is removed via wasted sludge without actual recovery. A novel approach to realize phosphorus recovery with special external chemical oxygen demand (COD) addition in EBPR process was proposed. During the new operating approach period, it was found that (1) no phosphorus was detected in the effluent; (2) with an external addition of 10 % of influent COD amount, 79 % phosphorus in the wastewater influent was recovered; (3) without wasted sludge, the MLVSS concentration in the system increased from 2,010 to 3,400 mg/L and kept stable after day 11 during 24-day operating period. This demonstrates that the novel approach is feasible to realize phosphorus recovery with no wasted sludge discharge in EBPR process. Furthermore, this approach decouples P removal and sludge age, which may enhance the application of membrane bioreactor for P removal. PMID:24122666

  6. Application of Ionizing Radiation to the Treatment of Waste Waters and Sewage Sludge

    International Nuclear Information System (INIS)

    There has recently been a revival of interest in the possible use of ionizing radiation in the treatment of waste waters, with applications as follows: disinfection; changes in the colloidal properties, as for example, settling rate, or filterability of sludges; radiation-induced oxidation of organic substances; and changes in biodegradability, e.g. modification of non-biodegradable substances to make them biodegradable. Published results are reviewed, appropriate criteria for satisfactory measurements are developed, and certain results are reported. Both continuous gamma irradiation from radioactive isotope sources and high dose rate irradiation from an electron linear accelerator have been used. The following conclusions have been reached: (1) Radiation-induced oxidation of organic material in waste waters does not appear economically feasible. A simple model of the radiation chemical processes occurring is given and it is concluded that oxidation of the organic materials occurs via conversion of dissolved O2 into active species as a result of attack by radicals formed by irradiation. A chain reaction is possible and is necessary for an economical process. Measurements of G-values for oxygen uptake and for decrease in oxidizable impurity in waste waters give results that are self- consistent and fit the model. No evidence of chain reactions has been observed in any case, and the maximum G-values found for oxidation are near 10. (2) Sludge beneficiation, i.e. improvement in properties such as settling or filterability, is more promising because the volume of sludge is typically only one per cent of that of waste water, and because the costs of sludge handling and disposal are high. Irradiation does increase the filterability of sludge, but the process is not economically competitive because similar results can be obtained with low concentrations of conditioning agents such as FeCl3, and because the effect saturates at too low a value to be useful. Irradiation does

  7. TGA–FTIR analysis of co-combustion characteristics of paper sludge and oil-palm solid wastes

    International Nuclear Information System (INIS)

    Highlights: • Co-combustion paper sludge with oil-palm solid wastes created significant changes. • Blending with oil-palm solid wastes could improve the combustion performance. • 10–30% of paper sludge in the blends could be determined as the optimum ratio range. • Co-combustion paper sludge with oil-palm solid wastes could reduce gaseous emissions. • The nth order reaction model could fit the co-combustion process very well. - Abstract: The kinetic thermal behavior and gaseous pollutant emissions of co-combustion between paper sludge and oil-palm solid wastes with a full range of blending ratio were investigated via a thermogravimetric simultaneous analyzer coupled with a Fourier transform infrared measurements. Co-combustion paper sludge with oil-palm solid wastes created significant changes in the thermal behaviors. With the exception of 10O90P blend, the combustion process of other blended fuels could be distinguished into three individual stages. The 90O10P blend showed the highest comprehensive combustion index (S = 5.59 × 10−07 min−2 °C−3) and the (dS/d(ratio)) reached the maximum at blended samples of 20O80P, these observations suggested the blending of paper sludge with oil-palm solid wastes improved the comprehensive combustion performance. Further analysis of the emission profiles of gaseous pollutants revealed that the co-combustion paper sludge and oil-palm solid wastes lead to a reduction in gaseous emissions (SO2, NO and CO2). Furthermore, co-combustion promoted the KCl of oil-palm solid wastes to convert into HCl in fuel gas, which could reduce the possibility of slagging, corrosion and fouling during co-combustion. The analysis results indicated 10–30% of paper sludge in the blends could be determined as the optimum ratio range for co-combustion paper sludge and oil-palm solid wastes. The nth order reaction model by the Coats–Redfern method was used to determine the kinetics parameters for the co-combustion of paper sludge

  8. Effects of Sludge Particle Size and Density on Hanford Waste Processing

    Energy Technology Data Exchange (ETDEWEB)

    Poloski, Adam P.; Wells, Beric E.; Mahoney, Lenna A.; Daniel, Richard C.; Tingey, Joel M.; Cooley, Scott K.

    2008-02-04

    The U.S. Department of Energy Office of River Protection’s Waste Treatment and Immobilization Plant (WTP) will process and treat radioactive waste that is stored in tanks at the Hanford Site in southeastern Washington State. Piping and pumps have been selected to transport the high-level waste (HLW) slurries in the WTP. Pipeline critical-velocity calculations for these systems require the input of a bounding particle size and density. Various approaches based on statistical analyses have been used in the past to provide an estimate of this bounding size and density. In this paper, representative particle size and density distributions (PSDDs) of Hanford waste insoluble solids have been developed based on a new approach that relates measured particle-size distributions (PSDs) to solid-phase compounds. This work was achieved through extensive review of available Hanford waste PSDs and solid-phase compound data. Composite PSDs representing the waste in up to 19 Hanford waste tanks were developed, and the insoluble solid-phase compounds for the 177 Hanford waste tanks, their relative fractions, crystal densities, and particle size and shape were developed. With such a large combination of particle sizes and particle densities, a Monte Carlo simulation approach was used to model the PSDDs. Further detail was added by including an agglomeration of these compounds where the agglomerate density was modeled with a fractal dimension relation. The Monte Carlo simulations were constrained to hold the following relationships: 1) the composite PSDs are reproduced, 2) the solid-phase compound mass fractions are reproduced, 3) the expected in situ bulk-solids density is qualitatively reproduced, and 4) a representative fraction of the sludge volume comprising agglomerates is qualitatively reproduced to typical Hanford waste values. Four PSDDs were developed and evaluated. These four PSDD scenarios correspond to permutations where the master PSD was sonicated or not

  9. The determination of PCBs in Rocky Flats Type IV waste sludge by gas chromatography/electron capture detection. Part 2

    International Nuclear Information System (INIS)

    Before disposal, radioactive sludge (Type IV) from Rocky Flats Plant (RFP) must be evaluated for polychlorinated biphenyl (PCB) content. The Type IV sludge consists of organic solvents, degreasers, cutting oils, and transuranic (TRU) waste mixed with calcium silicate (MicroCel E reg-sign and Oil Dri reg-sign to form a grease or paste-like material. For laboratory testing, a nonradioactive simulated Type 17V RFP sludge was prepared at Argonne National Laboratory-East (ANL-E). This sludge has a composition similar to that expected from field samples. In an earlier effort, a simplified method was developed for extraction, cleanup of extract, and determination of PCBs in samples of simulated sludge spiked with Aroclors 1254 and 1260. The simplified method has now been used to determine the presence and quantities of other Aroclors in the simulated sludge, namely, Aroclors 10 1 6, 1221, 1232, 1242, and 1248. The accuracy and precision of the data for these Aroclors were found to be similar to the data for sludges spiked with Aroclors 1254 and 1260. Since actual sludges may vary in composition, the method was also verified by analyzing another source of Type IV simulated sludge, prepared by Argonne National Laboratory-West (ANL-W)

  10. Effects of combined composting and vermicomposting of waste sludge on arsenic fate and bioavailability.

    Science.gov (United States)

    Maňáková, Blanka; Kuta, Jan; Svobodová, Markéta; Hofman, Jakub

    2014-09-15

    Composting and vermicomposting are traditional processes for the treatment of sludge. During these processes, the humification of organic matter has a significant effect on the physicochemical form and distribution of heavy metals. In this study, industrial sludge (groundwater treatment waste) contaminated by arsenic (396 ± 1 mg kg(-1)) was used. Such sludge poses a significant challenge with respect to effective treatment. Composting, vermicomposting (with Eisenia fetida), and the combined approach of composting and vermicomposting were performed to determine the evolution of arsenic speciation, mobility and bioavailability. The composting/vermicomposting was done with sludge, horse manure, and grass in the ratios of 3:6:1. A solution of 0.1M NH4COOCH3 was used as a single extraction solvent for determination of the mobile arsenic pool and targeted arsenic species (As(III), As(V), monomethylarsenic acid - MMA(V), dimethylarsenic acid - DMA(V)). The analysis of arsenic in the extracts was carried out by means of HPLC-ICP-MS spectrometry. In addition, the earthworm species E. fetida was used for bioaccumulation tests that followed the compost and vermicompost processes. The obtained results indicate a reduction in arsenic mobility and bioavailability in all matured composts and vermicomposts. The combined process exhibited a greater effect than compost or vermicompost alone. PMID:25209831

  11. A hybrid anaerobic membrane bioreactor coupled with online ultrasonic equipment for digestion of waste activated sludge.

    Science.gov (United States)

    Xu, Meilan; Wen, Xianghua; Yu, Zhiyong; Li, Yushan; Huang, Xia

    2011-05-01

    Anaerobic membrane bioreactor and online ultrasonic equipment used to enhance membrane filtration were coupled to form a hybrid system (US-AnMBR) designed for long-term digestion of waste activated sludge. The US-AnMBR was operated under volatile solids loading rates of 1.1-3.7 gVS/L·d. After comprehensive studies on digestion performance and membrane fouling control in the US-AnMBR, the final loading rate was determined to be 2.7 gVS/L·d with 51.3% volatile solids destruction. In the US-AnMBR, the improved digestion was due to enhanced sludge disintegration, as indicated by soluble matter comparison in the supernatant and particle size distribution in the digested sludge. Maximum specific methanogenic activity revealed that ultrasound application had no negative effect on anaerobic microorganisms. Furthermore, implementing ultrasound effectively controlled membrane fouling and successfully facilitated membrane bioreactor operation. This lab-scale study demonstrates the potential feasibility and effectiveness of setting up a US-AnMBR system for sludge digestion. PMID:21421308

  12. EFFECTIVENESS OF RECLAMATION OF SODA WASTE DISPOSAL SITE AT JANIKOWO USING SEWAGE SLUDGE

    Directory of Open Access Journals (Sweden)

    Jan Siuta

    2014-10-01

    Full Text Available There are numerous reclamation technologies based on sewage sludge treatment, however, one that is most purposeful consists in applying the sludge in order to achieve green cover (bioremediation with plants on fine grained waste disposal sites which have a high potential for soil formation on the one hand, but on the other, are highly vulnerable to erosive action of wind and atmospheric precipitation. The technological waste at the Janikowo Soda Plant has liquid consistence, contains fine-grained (dust-like and water soluble calcium compounds, and is highly alkaline and saline. The waste was disposed and dehydrated in the large-area earthen ponds elevated beyond the ground level. The combined surface of all the exploited settling ponds (with roads and escarpments jointly exceeds 105 ha. Dehydration by infiltration and evaporation was a source of unrestricted dust emissions from the drying and dry surfaces of the waste site. Urgent action was then deemed necessary to manage the high risk of nuisance dust to the local population, technical infrastructure, engines and cars. Consequently, it was decided that the best way to manage nuisance dust would be to create a thick and permanent vegetal cover on the waste site. The vegetal cover would also limit salt infiltration from the disposal site to groundwater and to adjacent agricultural land, and contribute to improving the local landscape values. Treatment with adequately high (appropriate for reclamation purposes doses of sewage sludge and sowing of plants which have a high growth potential and nutrient demand resulted in the quick establishment of green cover on the waste disposal site. The contents of mineral elements in plants and in the top layer of the ground reclaimed were analyzed starting from the year 2000 onwards until the year 2013. The chemical composition of sewage sludge was systematically analyzed as well. No excessive contents were found of main elements neither of heavy metals in

  13. Effects of Sludge Particle Size and Density on Hanford Waste Processing

    International Nuclear Information System (INIS)

    The U.S. Department of Energy Office of River Protection's Waste Treatment and Immobilization Plant (WTP) will process and treat radioactive waste that is stored in tanks at the Hanford Site in southeastern Washington State. Piping and pumps have been selected to transport the high-level waste (HLW) slurries in the WTP. Pipeline critical-velocity calculations for these systems require the input of a bounding particle size and density. Various approaches based on statistical analyses have been used in the past to provide an estimate of this bounding size and density. In this paper, representative particle size and density distributions (PSDDs) of Hanford waste insoluble solids have been developed based on a new approach that relates measured particle-size distributions (PSDs) to solid-phase compounds. This work was achieved through extensive review of available Hanford waste PSDs and solid-phase compound data. Composite PSDs representing the waste in up to 19 Hanford waste tanks were developed, and the insoluble solid-phase compounds for the 177 Hanford waste tanks, their relative fractions, crystal densities, and particle size and shape were developed. With such a large combination of particle sizes and particle densities, a Monte Carlo simulation approach was used to model the PSDDs. Further detail was added by including an agglomeration of these compounds where the agglomerate density was modeled with a fractal dimension relation. The Monte Carlo simulations were constrained to hold the following relationships: (1) the composite PSDs are reproduced, (2) the solid-phase compound mass fractions are reproduced, (3) the expected in situ bulk-solids density is qualitatively reproduced, and (4) a representative fraction of the sludge volume comprising agglomerates is qualitatively reproduced to typical Hanford waste values. Four PSDDs were developed and evaluated. These four PSDD scenarios correspond to permutations where the master PSD was sonicated or not

  14. Two-stage high temperature sludge gasification using the waste heat from hot blast furnace slags.

    Science.gov (United States)

    Sun, Yongqi; Zhang, Zuotai; Liu, Lili; Wang, Xidong

    2015-12-01

    Nowadays, disposal of sewage sludge from wastewater treatment plants and recovery of waste heat from steel industry, become two important environmental issues and to integrate these two problems, a two-stage high temperature sludge gasification approach was investigated using the waste heat in hot slags herein. The whole process was divided into two stages, i.e., the low temperature sludge pyrolysis at ⩽ 900°C in argon agent and the high temperature char gasification at ⩾ 900°C in CO2 agent, during which the heat required was supplied by hot slags in different temperature ranges. Both the thermodynamic and kinetic mechanisms were identified and it was indicated that an Avrami-Erofeev model could best interpret the stage of char gasification. Furthermore, a schematic concept of this strategy was portrayed, based on which the potential CO yield and CO2 emission reduction achieved in China could be ∼1.92∗10(9)m(3) and 1.93∗10(6)t, respectively. PMID:26409106

  15. Research on jet mixing of settled sludges in nuclear waste tanks at Hanford and other DOE sites: A historical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Powell, M.R.; Onishi, Y.; Shekarriz, R.

    1997-09-01

    Jet mixer pumps will be used in the Hanford Site double-shell tanks to mobilize and mix the settled solids layer (sludge) with the tank supernatant liquid. Predicting the performance of the jet mixer pumps has been the subject of analysis and testing at Hanford and other U.S. Department of Energy (DOE) waste sites. One important aspect of mixer pump performance is sludge mobilization. The research that correlates mixer pump design and operation with the extent of sludge mobilization is the subject of this report. Sludge mobilization tests have been conducted in tanks ranging from 1/25-scale (3 ft-diameter) to full scale have been conducted at Hanford and other DOE sites over the past 20 years. These tests are described in Sections 3.0 and 4.0 of this report. The computational modeling of sludge mobilization and mixing that has been performed at Hanford is discussed in Section 5.0.

  16. Research on jet mixing of settled sludges in nuclear waste tanks at Hanford and other DOE sites: A historical perspective

    International Nuclear Information System (INIS)

    Jet mixer pumps will be used in the Hanford Site double-shell tanks to mobilize and mix the settled solids layer (sludge) with the tank supernatant liquid. Predicting the performance of the jet mixer pumps has been the subject of analysis and testing at Hanford and other U.S. Department of Energy (DOE) waste sites. One important aspect of mixer pump performance is sludge mobilization. The research that correlates mixer pump design and operation with the extent of sludge mobilization is the subject of this report. Sludge mobilization tests have been conducted in tanks ranging from 1/25-scale (3 ft-diameter) to full scale have been conducted at Hanford and other DOE sites over the past 20 years. These tests are described in Sections 3.0 and 4.0 of this report. The computational modeling of sludge mobilization and mixing that has been performed at Hanford is discussed in Section 5.0

  17. Fermentative Hydrogen Production from Combination of Tofu processing and anaerobic digester sludge wastes using a microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    You-Kwan, O.; Mi-Sun, K.

    2009-07-01

    The combination of Tofu manufacturing waste and anaerobic digester sludge was studied for fermentative H{sub 2} production in batch and continuous modes using a mixed culture originated from sewage. In order to increase the solubilization of organic substrates from Tofu waste, various pretreatments including heat-treatment, acid/alkali treatment, and sonication were examined alone or in combination with others. (Author)

  18. Effect of Worm Predation on Changes in Waste Activated Sludge Properties.

    Science.gov (United States)

    Zhu, Xuefeng; Yuan, Wenyi; Wang, Zhiwei; Zhou, Mingyuan; Guan, Jie

    2016-05-01

    This study explored the effects of worm predation on changes in waste activated sludge properties. Results showed that the rate by which worm predation reduced mixed liquor volatile suspended solids (MLVSS) was approximately 23.7% ± 3.1%. Particle size distribution and extracellular polymeric substance (EPS) analyses indicated that the reduction of fine particles and EPS content in sludge predated by worms mainly increased dewaterability and reduced the ratio of MLVSS/mixed liquor suspended solids. Moreover, both mean particle size and protein/carbohydrate ratio increased. The results of three-dimensional excitation-emission matrix and gel filtration chromatogram analyses demonstrated the varied properties of soluble microbial products and EPS were attributed to the worms' selective predation of low molecular-weight organic matter, which facilitated the hydrolysis of macromolecular organic matter. PMID:27131302

  19. The Treatment of Low Level Radioactive Liquid Waste Containing Detergent by Biological Activated Sludge Process

    International Nuclear Information System (INIS)

    The treatment of low level radioactive liquid waste containing persil detergent from laundry operation of contaminated clothes by activated sludge process has been done, for alternative process replacing the existing treatment by evaporation. The detergent concentration in water solution from laundry operation is 14.96 g/l. After rinsing operation of clothes and mixing of laundry water solution with another liquid waste, the waste water solution contains about ≤ 1.496 g/l of detergent and 10-3 Ci/m3 of Cs-137 activity. The simulation waste having equivalent activity of Cs-137 10-3 Ci/m3, detergent content (X) 1.496, 0.748, 0.374, 0.187, 0.1496 and 0.094 g/l on BOD value respectively 186, 115, 71, 48, 19, and 16 ppm was processed by activated sludge in reactor of 18.6 l capacity on ambient temperature. It is used Super Growth Bacteria (SGB) 102 and SGB 104, nitrogen and phosphor nutrition, and aeration. The result show that bacteria of SGB 102 and SGB 104 were able to degrade the persil detergent for attaining standard quality of water release category B in which BOD values 6 ppm. It was need 30 hours for X ≤ 0.187 g/l, 50 hours for 0.187 < X ≤ 0.374 g/l, 75 hours for 0.374 < X ≤ 0.748, and 100 hours for 0.748 < X ≤ 1.496 g/l. On the initial period the bacteria of SGB 104 interact most quickly to degrade the detergent comparing SGB 102. Biochemical oxidation process decontaminate the solution on the decontamination factor of 350, Cs-137 be concentrate in sludge by complexing with the bacteria wall until the activity of solution be become very low. (author)

  20. Thermogravimetric analysis of the co-combustion of paper mill sludge and municipal solid waste

    International Nuclear Information System (INIS)

    Highlights: • Thermogravimetric analysis of paper mill sludge and municipal solid waste were studied. • The combustion of paper mill sludge could be improved by blending municipal solid waste. • There existed significant interaction during co-combustion of the blends. • The OFW and Starink methods were used to obtain the activation energy. • The average activation energy was the lowest by blending 20% municipal solid waste. - Abstract: The thermal characteristics and kinetics of paper mill sludge (PMS), municipal solid waste (MSW) and their blends in the combustion process were investigated in this study. The mass percentages of PMS in the blends were 10%, 30%, 50%, 70% and 90%, respectively. The experiments were carried out at different heating rates (10 °C/min, 20 °C/min and 30 °C/min) and the temperature ranged from room temperature to 1000 °C in a thermogravimetric simultaneous thermal analyzer. The results suggested that the ignition temperature and burnout temperature of MSW were lower than that of PMS, and the mass loss rate of MSW was larger especially at low temperatures. There were only two mass loss peaks in the differential thermogravimetry (DTG) curve, while three mass loss peaks were observed when the blending ratios of PMS were 30%, 50%, 70%. The value of the comprehensive combustion characteristic index of the blends indicated a good combustibility when the percentage of PMS (PPMS) in the blends was less than 30%. There existed certain interaction between the combustion process of PMS and MSW, especially at high temperature stage. Activation energy (E) value obtained by the Ozawa–Flynn–Wall (OFW) method and the Starink method were very consistent. When the mass percentage of PMS in the blends was 80%, the E average value attained the minimum

  1. Conditioning of cladding waste for long-term storage by press compaction and encapsulation in lead containment

    International Nuclear Information System (INIS)

    The conditioning of compacted cladding waste has been based on the concept of a corrosion-resistant containment. The technique of press compaction in remote operation conditions has been demonstrated. Detailed specifications of the design of the container are discussed in the report. Testing procedures for the different containment parts have been developed and applied. The remote welding techniques of the stainless steel and lead-based parts of the containment have been investigated and reliable procedures are reported. A technique for remote leak-testing of welded containers is described. The report contains a series of pictures documenting the entire conditioning concept, starting from the dissolver basket at the reprocessing stage up to the final disposal container

  2. Structural cladding /clad structures

    DEFF Research Database (Denmark)

    Beim, Anne

    2012-01-01

    Structural Cladding /Clad Structures: Studies in Tectonic Building Practice A. Beim CINARK – Centre for Industrialized Architecture, Institute of Architectural Technology, The Royal Danish Academy of Fine Arts School of Architecture, Copenhagen, Denmark ABSTRACT: With point of departure...... of materials, the structural features and the construction details of building systems in selected architectural works. With a particular focus at heavy constructions made of solid wood and masonry, and light weight constructions made of wooden frame structures and steel profiles, it is the intention...... tightness in constructions. At the same time a need for longevity and effortless maintenance have lead to contemporary architectural structures, where the exterior walls and the building envelope most often are made of several layers of advanced materials and separate building elements. In most contemporary...

  3. Towards a metagenomic understanding on enhanced biomethane production from waste activated sludge after pH 10 pretreatment

    Science.gov (United States)

    2013-01-01

    Background Understanding the effects of pretreatment on anaerobic digestion of sludge waste from wastewater treatment plants is becoming increasingly important, as impetus moves towards the utilization of sludge for renewable energy production. Although the field of sludge pretreatment has progressed significantly over the past decade, critical questions concerning the underlying microbial interactions remain unanswered. In this study, a metagenomic approach was adopted to investigate the microbial composition and gene content contributing to enhanced biogas production from sludge subjected to a novel pretreatment method (maintaining pH at 10 for 8 days) compared to other documented methods (ultrasonic, thermal and thermal-alkaline). Results Our results showed that pretreated sludge attained a maximum methane yield approximately 4-fold higher than that of the blank un-pretreated sludge set-up at day 17. Both the microbial and metabolic consortium shifted extensively towards enhanced biodegradation subsequent to pretreatment, providing insight for the enhanced methane yield. The prevalence of Methanosaeta thermophila and Methanothermobacter thermautotrophicus, together with the functional affiliation of enzymes-encoding genes suggested an acetoclastic and hydrogenotrophic methanogenesis pathway. Additionally, an alternative enzymology in Methanosaeta was observed. Conclusions This study is the first to provide a microbiological understanding of improved biogas production subsequent to a novel waste sludge pretreatment method. The knowledge garnered will assist the design of more efficient pretreatment methods for biogas production in the future. PMID:23506434

  4. DETERMINATION OF ACTIVATED SLUDGE MODEL ASDM PARAMETERS FOR WASTE WATER TREATMENT PLANT OPERATING IN THE SEQUENTIAL–FLOW TECHNOLOGY

    OpenAIRE

    Dariusz Zdebik

    2015-01-01

    This paper presents a method for calibration of activated sludge model with the use of computer program BioWin. Computer scheme has been developed on the basis of waste water treatment plant operating in the sequential – flow technology. For calibration of the activated sludge model data of influent and treated effluent from the existing object were used. As a result of conducted analysis was a change in biokinetic model and kinetic parameters parameters of wastewater treatment facilities. ...

  5. Peracetic acid oxidation as an alternative pre-treatment for the anaerobic digestion of waste activated sludge

    OpenAIRE

    Appels, Lise; Van Assche, Ado; Willems, Kris; Degrève, Jan; Impe, Jan Van; Dewil, Raf

    2011-01-01

    Anaerobic digestion is generally considered to be an economic and environmentally friendly technology for treating waste activated sludge, but has some limitations, such as the time it takes for the sludge to be digested and also the ineffectiveness of degrading the solids. Various pre-treatment technologies have been suggested to overcome these limitations and to improve the biogas production rate by enhancing the hydrolysis of organic matter. This paper studies the use of perace...

  6. Cone Penetrometer Shear Strength Measurements of Sludge Waste in Tanks 241-AN-101 and 241-AN-106

    Energy Technology Data Exchange (ETDEWEB)

    Follett, Jordan R.

    2014-03-06

    This document presents the resulting shear strength profiles for sludge waste in Tanks 241-AN-101 and 241-AN-106, as determined with a full-flow cone penetrometer. Full-flow penetrometer measurements indicate shear strength profiles that increase roughly uniformly with depth. For Tank 241-AN-101, the undrained shear strength was calculated to range from 500 Pa near the sludge surface to roughly 3,300 Pa at 15 inches above the tank bottom. For 241-AN-106, the undrained shear strength was calculated to range from 500 Pa near the sludge surface to roughly 5,000 Pa at 15 inches above the tank bottom.

  7. Effects of various pretreatments on biological sulfate reduction with waste activated sludge as electron donor and waste activated sludge diminution under biosulfidogenic condition

    International Nuclear Information System (INIS)

    The current study focused on the influences of various pretreatments, including alkaline, ultrasonic and thermal pretreatments on biological sulfate reduction with waste activated sludge (WAS) as sole electron donor. Our results showed that thermal and ultrasonic pretreatments increased the sulfate reduction percentage by 14.8% and 7.1%, respectively, compared with experiment with raw WAS, while alkaline pretreatment decreased the sulfate reduction percentage by 46%. By analyzing the WAS structure, particle size distribution, organic component, and enzyme activity after different pretreatments, we studied the effects of these pretreatments on WAS as well as on the mechanisms of how biological sulfate reduction was affected. The reduction of WAS and variation of WAS structure in the process of sulfate reduction were investigated. Our results showed that biosulfidogenesis was an efficient method of diminishing WAS, and various pretreatments could enhance the reduction efficiency of volatile solid in the WAS.

  8. Method of processing radioactive wastes

    International Nuclear Information System (INIS)

    Purpose: After removing clads from radioactive wastes, to dry and pulverize the same thereby to reduce hazard of radiation exposure and to obtain a large volume reduction ratio. Method: Regenerated liquid wastes, sludges and spent ion-exchange resin slurries within the tanks are respectively introduced into separation tanks, and the regenerated liquid wastes are sent into a mixing tank after clads within the separation tanks have been precipitated and separated. The sludges are applied with a supersonic wave in the separation tanks, and thereafter are passed through an electromagnetic filter. Then, clads are removed from the sludges, and thereafter the sludges are sent into the mixing tank. The spent ion-exchange resin slurries are applied with a supersonic wave and stirred in the separation tanks, and sent into the mixing tank after the clads have been precipitated and separated. The mixture which has been prepared in the mixing tank is dried and pulverized by a centrifugal film drier, and mixed with burnt ashes discharged from a hopper. Then, the mixture is pelletized and asphalt-hardened. (Yoshino, Y.)

  9. Modeling water retention of sludge simulants and actual saltcake tank wastes

    International Nuclear Information System (INIS)

    The Ferrocyanide Tanks Safety Program managed by Westinghouse hanford Company has been concerned with the potential combustion hazard of dry tank wastes containing ferrocyanide chemical in combination with nitrate salts. Pervious studies have shown that tank waste containing greater than 20 percent of weight as water could not be accidentally ignited. Moreover, a sustained combustion could not be propagated in such a wet waste even if it contained enough ferrocyanide to burn. Because moisture content is a key critical factor determining the safety of ferrocyanide-containing tank wastes, physical modeling was performed by Pacific Northwest National laboratory to evaluate the moisture-retaining behavior of typical tank wastes. The physical modeling reported here has quantified the mechanisms by which two main types of tank waste, sludge and saltcake, retain moisture in a tank profile under static conditions. Static conditions usually prevail after a tank profile has been stabilized by pumping out any excess interstitial liquid, which is not naturally retained by the waste as a result of physical forces such as capillarity

  10. Baseline data on radioactivity in drinking water, groundwater, waste water, sewage sludge, residues, and wastes, referring to annual report 1989 'Environmental radioactivity and radiation exposure'

    International Nuclear Information System (INIS)

    This issue of the WaBoLu series gives a comprehensive survey of the radioactivity in drinking water, groundwater, waste water, sewage sludge, residues and wastes in the FRG, as measured in the year 1989 and compiled by the Leitstelle of the WaBoLu Institute of the Federal Board of Health. (orig.)

  11. DEFENSE WASTE PROCESSING FACILITY ANALYTICAL METHOD VERIFICATION FOR THE SLUDGE BATCH 5 QUALIFICATION SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Click, D; Tommy Edwards, T; Henry Ajo, H

    2008-07-25

    For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs confirmation of the applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples. DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem Method, see Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICP-AES). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium Peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestion of Sludge Batch 5 (SB5) SRAT Receipt and SB5 SRAT Product samples. The SB5 SRAT Receipt and SB5 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB5 Batch composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 4 (SB4), to form the SB5 Blend composition. The results for any one particular element should not be used in any way to identify the form or speciation of a particular element in the sludge or used to estimate ratios of compounds in the sludge. A statistical comparison of the data validates the use of the DWPF CC method for SB5 Batch composition. However, the difficulty that was encountered in using the CC method for SB4 brings into question the adequacy of CC for the SB5 Blend. Also, it should be noted that visible solids remained in the final diluted solutions of all samples digested by this method at SRNL (8 samples total), which is typical for the DWPF CC method but not seen in the other methods. Recommendations to the DWPF for application to SB5 based on studies to date: (1) A dissolution study should be performed on the WAPS

  12. 5.2. Obtaining of cryolite-alumina concentrate from sludge and sifting of storage of solid wastes by flotation method

    International Nuclear Information System (INIS)

    The method of obtaining of cryolite-alumina concentrate from sludge and sifting of storage of solid wastes by means of flotation method was elaborated. The flowsheet of obtaining of cryolite-alumina concentrate from sludge and sifting of storage of solid wastes by means of flotation method was considered and presented in this article. The flowsheet of flotation of washed sludge was considered as well.

  13. Study on Influence to Waste Water Treatment Plant’s Sludge by Low-carbon Catalytic Combustion Furnace of Natural Gas

    OpenAIRE

    Ren TianQi; Fang Kai; Zhang Shihong

    2016-01-01

    There are two parts in this experiment. One of is about the concentration of Variation of exhaust gas while heating sludge of waste water treatment plant. The other one is about introduce the problems of the traditional incineration processes of sludge of waste water treatment as compared between the sludge heated by natural gas catalytic combustion furnace and the tradition’s. We can see that natural gas low-carbon catalytic combustion furnace realize the near-zero emission of contaminates.

  14. Frit Optimization For Sludge Batch Processing At The Defense Waste Processing Facility

    International Nuclear Information System (INIS)

    The Savannah River National Laboratory (SRNL) Frit Development Team recommends that the Defense Waste Processing Facility (DWPF) utilize Frit 418 for initial processing of high level waste (HLW) Sludge Batch 5 (SB5). The extended SB5 preparation time and need for DWPF feed have necessitated the use of a frit that is already included on the DWPF procurement specification. Frit 418 has been used previously in vitrification of Sludge Batches 3 and 4. Paper study assessments predict that Frit 418 will form an acceptable glass when combined with SB5 over a range of waste loadings (WLs), typically 30-41% based on nominal projected SB5 compositions. Frit 418 has a relatively high degree of robustness with regard to variation in the projected SB5 composition, particularly when the Na2O concentration is varied. The acceptability (chemical durability) and model applicability of the Frit 418-SB5 system will be verified experimentally through a variability study, to be documented separately. Frit 418 has not been designed to provide an optimal melt rate with SB5, but is recommended for initial processing of SB5 until experimental testing to optimize a frit composition for melt rate can be completed. Melt rate performance can not be predicted at this time and must be determined experimentally. Note that melt rate testing may either identify an improved frit for SB5 processing (one which produces an acceptable glass at a faster rate than Frit 418) or confirm that Frit 418 is the best option.

  15. Correlation between Organic Matter Degradation and the Rheological Performance of Waste Sludge During Anaerobic Digestion

    Science.gov (United States)

    Morel, Evangelina S.; Hernández-Hernándes, José A.; Méndez-Contreras, Juan M.; Cantú-Lozano, Denis

    2008-07-01

    Anaerobic digestion has demonstrated to be a good possibility to reduce the organic matter contents in waste activated sludge resulting in the effluents treatment. An anaerobic digestion was carried out in a 3.5 L reactor at 35 °C for a period of 20 days. An electronic thermostat controlled the temperature. The reactor was agitated at a rate of 200 rpm. The study of the rheological behavior of the waste activated sludge was done with an Anton Paar™ rheometer model MCR301 with a peltier plate for temperature control. Four-blade vane geometry was used with samples of 37 mL for determining rheological properties. Sampling (two samples) was taken every four days of anaerobic digestion through a peristaltic pump. The samples behavior was characterized by the Herschel-Bulkley model, with R2>0.99 for most cases. In all samples were found an apparent viscosity (ηap) and yield stress (τo) decrement when organic matter content diminishes. This demonstrates a relationship between rheological properties and organic matter concentration (% volatile solids). Also the flow activation energy (Ea) was calculated using the Ahrrenius correlation and samples of waste activated sludge before anaerobic digestion. In this case, samples were run in the rheometer at 200 rpm and a temperature range of 25 to 75 °C with an increment rate of 2 °C per minute. The yield stress observed was in a range of 0.93-0.18 Pa, the apparent viscosity was in a range of 0.0358-0.0010 Pa.s, the reduction of organic matter was in a range of 62.57-58.43% volatile solids and the average flow activation energy was 1.71 Calṡg-mol-1.

  16. Co-digestion of mixed sewage sludge and fruit and vegetables wastes effect of different mixtures on biogas yield

    OpenAIRE

    Arhoun, B.; Gómez-Lahoz, C.; Rodríguez-Maroto, JM.; García Herruzo, Francisco; Vereda-Alonso, C.

    2015-01-01

    Disposal of fruit and vegetable wastes (FVWs) in landfill site cause serious environmental issues such as contamination of soil, air and ground water. These wastes contain large quantities of biodegradable organic fractions, with high moisture that facilitates their biological treatment. One of the best alternatives to landfill disposal of these wastes is the anaerobic digestion. Therefore, it is one of the most widespread stabilization processes of the sludge in municipal wastewater treatmen...

  17. Testing Of Enhanced Chemical Cleaning Of SRS Actual Waste Tank 5F And Tank 12H Sludges

    International Nuclear Information System (INIS)

    Forty three of the High Level Waste (HLW) tanks at the Savannah River Site (SRS) have internal structures that hinder removal of the last approximately five thousand gallons of waste sludge solely by mechanical means. Chemical cleaning can be utilized to dissolve the sludge heel with oxalic acid (OA) and pump the material to a separate waste tank in preparation for final disposition. This dissolved sludge material is pH adjusted downstream of the dissolution process, precipitating the sludge components along with sodium oxalate solids. The large quantities of sodium oxalate and other metal oxalates formed impact downstream processes by requiring additional washing during sludge batch preparation and increase the amount of material that must be processed in the tank farm evaporator systems and the Saltstone Processing Facility. Enhanced Chemical Cleaning (ECC) was identified as a potential method for greatly reducing the impact of oxalate additions to the SRS Tank Farms without adding additional components to the waste that would extend processing or increase waste form volumes. In support of Savannah River Site (SRS) tank closure efforts, the Savannah River National Laboratory (SRNL) conducted Real Waste Testing (RWT) to evaluate an alternative to the baseline 8 wt. % OA chemical cleaning technology for tank sludge heel removal. The baseline OA technology results in the addition of significant volumes of oxalate salts to the SRS tank farm and there is insufficient space to accommodate the neutralized streams resulting from the treatment of the multiple remaining waste tanks requiring closure. ECC is a promising alternative to bulk OA cleaning, which utilizes a more dilute OA (nominally 2 wt. % at a pH of around 2) and an oxalate destruction technology. The technology is being adapted by AREVA from their decontamination technology for Nuclear Power Plant secondary side scale removal. This report contains results from the SRNL small scale testing of the ECC process

  18. TESTING OF ENHANCED CHEMICAL CLEANING OF SRS ACTUAL WASTE TANK 5F AND TANK 12H SLUDGES

    Energy Technology Data Exchange (ETDEWEB)

    Martino, C.; King, W.

    2011-08-22

    Forty three of the High Level Waste (HLW) tanks at the Savannah River Site (SRS) have internal structures that hinder removal of the last approximately five thousand gallons of waste sludge solely by mechanical means. Chemical cleaning can be utilized to dissolve the sludge heel with oxalic acid (OA) and pump the material to a separate waste tank in preparation for final disposition. This dissolved sludge material is pH adjusted downstream of the dissolution process, precipitating the sludge components along with sodium oxalate solids. The large quantities of sodium oxalate and other metal oxalates formed impact downstream processes by requiring additional washing during sludge batch preparation and increase the amount of material that must be processed in the tank farm evaporator systems and the Saltstone Processing Facility. Enhanced Chemical Cleaning (ECC) was identified as a potential method for greatly reducing the impact of oxalate additions to the SRS Tank Farms without adding additional components to the waste that would extend processing or increase waste form volumes. In support of Savannah River Site (SRS) tank closure efforts, the Savannah River National Laboratory (SRNL) conducted Real Waste Testing (RWT) to evaluate an alternative to the baseline 8 wt. % OA chemical cleaning technology for tank sludge heel removal. The baseline OA technology results in the addition of significant volumes of oxalate salts to the SRS tank farm and there is insufficient space to accommodate the neutralized streams resulting from the treatment of the multiple remaining waste tanks requiring closure. ECC is a promising alternative to bulk OA cleaning, which utilizes a more dilute OA (nominally 2 wt. % at a pH of around 2) and an oxalate destruction technology. The technology is being adapted by AREVA from their decontamination technology for Nuclear Power Plant secondary side scale removal. This report contains results from the SRNL small scale testing of the ECC process

  19. Microbial electrolysis contribution to anaerobic digestion of waste activated sludge, leading to accelerated methane production

    DEFF Research Database (Denmark)

    Liu, Wenzong; Cai, Weiwei; Guo, Zechong;

    2016-01-01

    Methane production rate (MPR) in waste activated sludge (WAS) digestion processes is typically limitedby the initial steps of complex organic matter degradation, leading to a limited MPR due to sludgefermentation speed of solid particles. In this study, a novel microbial electrolysis AD reactor (ME....../m3 reactor/d in AD). The methane production yield reached 116.2 mg/g VSS in the ME-ADreactor. According to balance calculation on electron transfer and methane yield, the increasedmethane production was mostly dependent on electron contribution through the ME system. Thus, theuse of the novel ME...

  20. Bio-Gas production from municipal sludge waste using anaerobic membrane bioreactor

    International Nuclear Information System (INIS)

    A laboratory scale anaerobic membrane bioreactor (AnMBR) system for the bio-methane gas production was operated for 60 days with municipal sludge wastes as a sole carbon source. The AnMRR system utilized the external cross-flow membrane module and was equipped with on-line data acquisition which enables continuous monitoring of the performance of both bioreactor and membrane through the analyses of pH, temperature, gas production; permeate flow rate, and transmembrane pressure (TMP). Such a configuration also provides an efficient tool to study rapid variations of monitoring membrane pressure (TMP). (Author)

  1. Remove and recover phosphorus during anaerobic digestion of excess sludge by adding waste iron scrap

    OpenAIRE

    Zheng Wei; Li Xiao Ming; Wang Dong Bo; Yang Qi; Luo Kun; Jing Yang Guo; Zeng Guang Ming

    2013-01-01

    In the current investigation, the feasibility of phosphorus removal in the anaerobic digestion of excess sludge by adding waste iron scrap (WIS) was studied. The results show that the removal efficiency of phosphorus increases with the amount of WIS, and the maximum removal efficiency could reach 39%, 93% and 99% at WIS dosages of 1, 2 and 3 g/L, respectively. Sterilization greatly decreases the removal efficiency of phosphorus, having only -6%, 53% and 64% at WIS dosages of 1, 2 and 3 ...

  2. Bio-Gas production from municipal sludge waste using anaerobic membrane bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. H.; Lee, S.

    2009-07-01

    A laboratory scale anaerobic membrane bioreactor (AnMBR) system for the bio-methane gas production was operated for 60 days with municipal sludge wastes as a sole carbon source. The AnMRR system utilized the external cross-flow membrane module and was equipped with on-line data acquisition which enables continuous monitoring of the performance of both bioreactor and membrane through the analyses of pH, temperature, gas production; permeate flow rate, and transmembrane pressure (TMP). Such a configuration also provides an efficient tool to study rapid variations of monitoring membrane pressure (TMP). (Author)

  3. Effects of microwave irradiation on dewaterability and extracellular polymeric substances of waste activated sludge.

    Science.gov (United States)

    Peng, Ge; Ye, Fenxia; Ye, Yangfang

    2013-03-01

    The effects of microwave irradiation on filterability and dewaterability of waste activated sludge measured by capillary suction time (CST) and dry solids in sludge cake were investigated. The results showed that the optimum irradiation time improved filterability, but that further increase of the time was detrimental. Dewaterability was enhanced significantly and increased with microwave time. Filterability and dewaterability were improved 25 to 28% and 1.3 times at the optimum times of 30 and 90 seconds for the sludge of 5 g total suspended solids (TSS)/L and 7 g TSS/L, respectively. The floc size decreased slightly. Loosely bound extracellular polymeric substances (LB-EPS) decreased under optimum time, but tightly bound extracellular polymeric substances did not change significantly after short irradiation time. The results implied that LB-EPS played a more important role in the observed changes of filterability and dewaterability and that the double-layered extracellular polymeric substances extraction method showed marked implications to dewaterability. PMID:23581243

  4. The Potential in Bioethanol Production From Waste Fiber Sludges in Pulp Mill-Based Biorefineries

    Science.gov (United States)

    Sjöde, Anders; Alriksson, Björn; Jönsson, Leif J.; Nilvebrant, Nils-Olof

    Industrial production of bioethanol from fibers that are unusable for pulp production in pulp mills offers an approach to product diversification and more efficient exploitation of the raw material. In an attempt to utilize fibers flowing to the biological waste treatment, selected fiber sludges from three different pulp mills were collected, chemically analyzed, enzymatically hydrolyzed, and fermented for bioethanol production. Another aim was to produce solid residues with higher heat values than those of the original fiber sludges to gain a better fuel for combustion. The glucan content ranged between 32 and 66% of the dry matter. The lignin content varied considerably (1-25%), as did the content of wood extractives (0.2-5.8%). Hydrolysates obtained using enzymatic hydrolysis were found to be readily fermentable using Saccharomyces cerevisiae. Hydrolysis resulted in improved heat values compared with corresponding untreated fiber sludges. Oligomeric xylan fragments in the solid residue obtained after enzymatic hydrolysis were identified using matrix-assisted laser desorption ionization-time of flight and their potential as a new product of a pulp mill-based biorefinery is discussed.

  5. Harnessing dark fermentative hydrogen from pretreated mixture of food waste and sewage sludge under sequencing batch mode.

    Science.gov (United States)

    Nam, Joo-Youn; Kim, Dong-Hoon; Kim, Sang-Hyoun; Lee, Wontae; Shin, Hang-Sik; Kim, Hyun-Woo

    2016-04-01

    Food waste and sewage sludge are the most abundant and problematic organic wastes in any society. Mixture of these two wastes may provide appropriate substrate condition for dark fermentative biohydrogen production based on synergistic mutual benefits. This work evaluates continuous hydrogen production from the cosubstrate of food waste and sewage sludge to verify mechanisms of performance improvement in anaerobic sequencing batch reactors. Volatile solid concentration and mixing ratio of food waste and sludge were adjusted to 5 % and 80:20, respectively. Five different hydraulic retention times (HRT) of 36, 42, 48, 72, and 108 h were tested using anaerobic sequencing batch reactors to find out optimal operating condition. Results show that the best performance was achieved at HRT 72 h, where the hydrogen yield, the hydrogen production rate, and hydrogen content were 62.0 mL H2/g VS, 1.0 L H2/L/day, and ~50 %, respectively. Sufficient solid retention time (143 h) and proper loading rate (8.2 g COD/L/day as carbohydrate) at HRT 72h led to the enhanced performance with better hydrogen production showing appropriate n-butyrate/acetate (B/A) ratio of 2.6. Analytical result of terminal-restriction fragment length polymorphism revealed that specific peaks associated with Clostridium sp. and Bacillus sp. were strongly related to enhanced hydrogen production from the cosubstrate of food waste and sewage sludge. PMID:26150291

  6. Compaction test of fuel element claddings (hulls) and fuel structures waste. 1

    International Nuclear Information System (INIS)

    The PNC (Power and Nuclear Fuel Development Corporation) plans a hull (fuel element cladding) and endpiece hardware compaction facility in Tokai Works. These tests are carried out to confirm the compaction method to be applied. A Series of tests consist of selection of 'simulated hull material', 'design of capsule', 'correlation between pressure and volume reduction ratio', 'estimation of the disk condition' and 'release of zircalloy-fines from the disk during the compressing process'. The results of these tests are as follows. 1) Non-annealing zircalloy for simulated hull material. 2) Optimization of the capsule design. 3) About 80 wt % of the theoretical zircalloy density at 390 MPa pressure. 4) No large void in the disk without cutting the endpiece. 5) The scattering zircalloy fines volume is about 30ppb by the pressing treatment. This test confirm the compaction to be applied. (author)

  7. Study of Structural Performance and Durability of Concrete by Partial Replacement of Cement with Hypo Sludge (Paper waste

    Directory of Open Access Journals (Sweden)

    K. Hari kishan,

    2015-12-01

    Full Text Available Utilization of industrial waste products as supplementary cementitious materials (SCM in concrete making is very important aspect in view of economical, environmental and technical reasons. As these supplementary cementitious materials have different chemical and mineralogical composition, their effect on micro structural properties and strength performance vary considerably. While producing paper, various wastes come out from the various processes in paper industries. The preliminary waste from paper industry is named as hypo sludge. In this study the material obtained from the paper industry waste (hypo sludge is admixed with Portland cement at different replacement levels. The properties of concrete investigated include compressive strength, split tensile strength, flexural strength, sorptivity and acid effect keeping optimum percentage of hypo sludge supposedly supplementary cementitious material (SCM. In this work, M20 grade was developed using IS method of mix design. Specimens of dimensions of 150 x 300mm cylinders for split tensile strength and dimensions of 100 x 100 x 500mm prisms for flexure strength and 150*150*150mm cubes were cast, with and without hypo sludge and tested under axial compression to justify the compressive strength for 7 and 28 days. Standard cubes were immersed in 5%HCL, 5%H2SO4 for inspecting the durability properties. The Sorptivity test has also been conducted. It is concluded that hypo sludge concrete had better mechanical properties and durability properties compared to normal concrete. Test results indicate that the use of hypo sludge in concrete has improved the performance of concrete from strength as well as durability aspects. The split tensile strength is less in hypo sludge concrete compared to normal concrete.

  8. High-Level Waste Mechanical Sludge Removal at the Savannah River Site - F Tank Farm Closure Project

    International Nuclear Information System (INIS)

    The Savannah River Site F-Tank Farm Closure project has successfully performed Mechanical Sludge Removal (MSR) using the Waste on Wheels (WOW) system for the first time within one of its storage tanks. The WOW system is designed to be relatively mobile with the ability for many components to be redeployed to multiple waste tanks. It is primarily comprised of Submersible Mixer Pumps (SMPs), Submersible Transfer Pumps (STPs), and a mobile control room with a control panel and variable speed drives. In addition, the project is currently preparing another waste tank for MSR utilizing lessons learned from this previous operational activity. These tanks, designated as Tank 6 and Tank 5 respectively, are Type I waste tanks located in F-Tank Farm (FTF) with a capacity of 2,840 cubic meters (750,000 gallons) each. The construction of these tanks was completed in 1953, and they were placed into waste storage service in 1959. The tank's primary shell is 23 meters (75 feet) in diameter, and 7.5 meters (24.5 feet) in height. Type I tanks have 34 vertically oriented cooling coils and two horizontal cooling coil circuits along the tank floor. Both Tank 5 and Tank 6 received and stored F-PUREX waste during their operating service time before sludge removal was performed. DOE intends to remove from service and operationally close (fill with grout) Tank 5 and Tank 6 and other HLW tanks that do not meet current containment standards. Mechanical Sludge Removal, the first step in the tank closure process, will be followed by chemical cleaning. After obtaining regulatory approval, the tanks will be isolated and filled with grout for long-term stabilization. Mechanical Sludge Removal operations within Tank 6 removed approximately 75% of the original 95,000 liters (25,000 gallons). This sludge material was transferred in batches to an interim storage tank to prepare for vitrification. This operation consisted of eleven (11) Submersible Mixer Pump(s) mixing campaigns and multiple intra

  9. Defense Waste Processing Facility Simulant Chemical Processing Cell Studies for Sludge Batch 9

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Tara E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, J. David [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Woodham, Wesley H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-08-10

    The Savannah River National Laboratory (SRNL) received a technical task request from Defense Waste Processing Facility (DWPF) and Saltstone Engineering to perform simulant tests to support the qualification of Sludge Batch 9 (SB9) and to develop the flowsheet for SB9 in the DWPF. These efforts pertained to the DWPF Chemical Process Cell (CPC). CPC experiments were performed using SB9 simulant (SB9A) to qualify SB9 for sludge-only and coupled processing using the nitric-formic flowsheet in the DWPF. Two simulant batches were prepared, one representing SB8 Tank 40H and another representing SB9 Tank 51H. The simulant used for SB9 qualification testing was prepared by blending the SB8 Tank 40H and SB9 Tank 51H simulants. The blended simulant is referred to as SB9A. Eleven CPC experiments were run with an acid stoichiometry ranging between 105% and 145% of the Koopman minimum acid equation (KMA), which is equivalent to 109.7% and 151.5% of the Hsu minimum acid factor. Three runs were performed in the 1L laboratory scale setup, whereas the remainder were in the 4L laboratory scale setup. Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) cycles were performed on nine of the eleven. The other two were SRAT cycles only. One coupled flowsheet and one extended run were performed for SRAT and SME processing. Samples of the condensate, sludge, and off-gas were taken to monitor the chemistry of the CPC experiments.

  10. Biological short-chain fatty acids (SCFAs) production from waste-activated sludge affected by surfactant.

    Science.gov (United States)

    Jiang, Su; Chen, Yinguang; Zhou, Qi; Gu, Guowei

    2007-07-01

    Short-chain fatty acids (SCFAs), the preferred carbon sources for biological nutrient removal, are the important intermediate products in sludge anaerobic fermentation. Sodium dodecylbenzene sulfonate (SDBS) is a widespread used surfactant, which can be easily found in waste-activated sludge (WAS). In this investigation, the effect of SDBS on SCFAs production from WAS was investigated, and the potential of using fermentative SCFAs to promote enhanced biological phosphorus removal (EBPR) was tested. Results showed that the total SCFAs production increased significantly in the presence of SDBS at room temperature. At fermentation time of 6 days, the maximum SCFAs was 2599.1mg chemical oxygen demand (COD)/L in the presence of SDBS 0.02g/g, whereas it was only 339.1mg (COD)/L in the absence of SDBS. The SCFAs produced in the case of SDBS 0.02g/g and fermentation time 6 days consisted of acetic acid (27.1%), propionic acid (22.8%), iso-valeric acid (20.1%), iso-butyric acid (11.9%), n-butyric acid (10.4%) and n-valeric acid (7.7%). It was found that during sludge anaerobic fermentation, the solubilization of sludge particulate organic-carbon and hydrolysis of solubilized substrate as well as acidification of hydrolyzed products were all increased in the presence of SDBS, while the methane formation was decreased, the SCFAs production was therefore remarkably improved. Further investigation showed that the production of SCFAs enhanced by SDBS was caused mainly by biological effects, rather than by chemical effects and SDBS decomposition. With the fermentative SCFAs as the main carbon source, the EBPR maintained high phosphorus removal efficiency ( approximately 97%). PMID:17499838

  11. Waste paper and clinoptilolite as a bulking material with dewatered anaerobically stabilized primary sewage sludge (DASPSS) for compost production.

    Science.gov (United States)

    Zorpas, Antonis A; Arapoglou, Dimitris; Panagiotis, Karlis

    2003-01-01

    Environmental problems associated with sewage sludge disposal have prompted strict legislative actions over the past few years. At the same time, the upgrading and expansion of wastewater treatment plants have greatly increased the volume of sludge generated. The major limitation of land application of sewage sludge compost is the potential for high heavy metal content in relation to the metal content of the original sludge. Composting of sewage sludge with natural zeolite (clinoptilolite) can enhance its quality and suitability for agricultural use. However, the dewatered anaerobically stabilized primary sewage sludge (DASPSS) contained a low concentration of humic substances (almost 2%), and the addition of the waste paper was necessary in order to produce a good soil conditioner with high concentrations of humics. The final results showed that the compost produced from DASPSS and 40-50% w/w of waste paper was a good soil fertilizer. Finally, in order to estimate the metal leachability of the final compost product, the generalized acid neutralization Capacity (GANC) procedure was used, and it was found that by increasing the leachate pH, the heavy metal concentration decreased. The application of the sequential chemical extraction indicated that metals were bound to the residual fraction characterized as a stabilize fractions. PMID:12623099

  12. Leachability of Heavy Metals from Lightweight Aggregates Made with Sewage Sludge and Municipal Solid Waste Incineration Fly Ash

    Directory of Open Access Journals (Sweden)

    Na Wei

    2015-05-01

    Full Text Available Lightweight aggregate (LWA production with sewage sludge and municipal solid waste incineration (MSWI fly ash is an effective approach for waste disposal. This study investigated the stability of heavy metals in LWA made from sewage sludge and MSWI fly ash. Leaching tests were conducted to find out the effects of MSWI fly ash/sewage sludge (MSWI FA/SS ratio, sintering temperature and sintering time. It was found that with the increase of MSWI FA/SS ratio, leaching rates of all heavy metals firstly decreased and then increased, indicating the optimal ratio of MSWI fly ash/sewage sludge was 2:8. With the increase of sintering temperature and sintering time, the heavy metal solidifying efficiencies were strongly enhanced by crystallization and chemical incorporations within the aluminosilicate or silicate frameworks during the sintering process. However, taking cost-savings and lower energy consumption into account, 1100 °C and 8 min were selected as the optimal parameters for LWA sample- containing sludge production. Furthermore, heavy metal leaching concentrations under these optimal LWA production parameters were found to be in the range of China’s regulatory requirements. It is concluded that heavy metals can be properly stabilized in LWA samples containing sludge and cannot be easily released into the environment again to cause secondary pollution.

  13. A novel conditioning process for enhancing dewaterability of waste activated sludge by combination of zero-valent iron and persulfate.

    Science.gov (United States)

    Zhou, Xu; Wang, Qilin; Jiang, Guangming; Liu, Peng; Yuan, Zhiguo

    2015-06-01

    Improvement of sludge dewaterability is crucial for reducing the costs of sludge disposal in wastewater treatment plants. This study presents a novel conditioning method for improving waste activated sludge dewaterability by combination of persulfate and zero-valent iron. The combination of zero-valent iron (0-30g/L) and persulfate (0-6g/L) under neutral pH substantially enhanced the sludge dewaterability due to the advanced oxidization reactions. The highest enhancement of sludge dewaterability was achieved at 4g persulfate/L and 15g zero-valent iron/L, with which the capillary suction time was reduced by over 50%. The release of soluble chemical oxygen demand during the conditioning process implied the decomposition of sludge structure and microorganisms, which facilitated the improvement of dewaterability due to the release of bound water that was included in sludge structure and microorganism. Economic analysis showed that the proposed conditioning process with persulfate and ZVI is more economically favorable for improving WAS dewaterability than classical Fenton reagent. PMID:25804531

  14. Enhanced digestion of waste activated sludge using microbial electrolysis cells at ambient temperature.

    Science.gov (United States)

    Asztalos, Joseph R; Kim, Younggy

    2015-12-15

    This study examined the effects of the microbial electrolysis cell (MEC) reactions on anaerobic digestion of waste activated sludge from municipal wastewater treatment under ambient temperature conditions (22-23 °C). Two lab-scale digesters, a control anaerobic digester and an electrically-assisted digester (EAD - equipped with a MEC bioanode and cathode) were operated under three solids retention times (SRT = 7, 10 and 14 days) at 22.5 ± 0.5 °C. A numerical model was also built by including the MEC electrode reactions in Anaerobic Digestion Model No.1. In experiments, the EAD showed reduced concentration of acetic acid, propionic acid, n-butyric acid and iso-butyric acid. This improved performance of the EAD is thought to be achieved by direct oxidation of the short-chain fatty acids at the bioanode as well as indirect contribution of low acetic acid concentration to enhancing beta-oxidation. The VSS and COD removal was consistently higher in the EAD by 5-10% compared to the control digester for all SRT conditions at 22.5 ± 0.5 °C. When compared to mathematical model results, this additional COD removal in the EAD was equivalent to that which would be achieved with conventional digesters at mesophilic temperatures. The magnitude of electric current in the EAD was governed by the organic loading rate while conductivity and acetic acid concentration showed negligible effects on current generation. Very high methane content (∼95%) in the biogas from both the EAD and control digester implies that the waste activated sludge contained large amounts of lipids and other complex polymeric substances compared to primary sludge. PMID:26051356

  15. Anaerobic Codigestion of Sludge: Addition of Butcher's Fat Waste as a Cosubstrate for Increasing Biogas Production.

    Science.gov (United States)

    Martínez, E J; Gil, M V; Fernandez, C; Rosas, J G; Gómez, X

    2016-01-01

    Fat waste discarded from butcheries was used as a cosubstrate in the anaerobic codigestion of sewage sludge (SS). The process was evaluated under mesophilic and thermophilic conditions. The codigestion was successfully attained despite some inhibitory stages initially present that had their origin in the accumulation of volatile fatty acids (VFA) and adsorption of long-chain fatty acids (LCFA). The addition of a fat waste improved digestion stability and increased biogas yields thanks to the higher organic loading rate (OLR) applied to the reactors. However, thermophilic digestion was characterized by an effluent of poor quality and high VFA content. Results from spectroscopic analysis suggested the adsorption of lipid components onto the anaerobic biomass, thus disturbing the complete degradation of substrate during the treatment. The formation of fatty aggregates in the thermophilic reactor prevented process failure by avoiding the exposure of biomass to the toxic effect of high LCFA concentrations. PMID:27071074

  16. XRF and leaching characterization of waste glasses derived from wastewater treatment sludges

    International Nuclear Information System (INIS)

    Purpose of this study was to investigate use of XRF (x-ray fluorescence spectrometry) as a near real-time method to determine melter glass compositions. A range of glasses derived from wastewater treatment sludges associated with DOE sites was prepared. They were analyzed by XRF and wet chemistry digestion with atomic absorption/inductively coupled emission spectrometry. Results indicated good correlation between these two methods. A rapid sample preparation and analysis technique was developed and demonstrated by acquiring a sample from a pilot-scale simulated waste glass melter and analyzing it by XRF within one hour. From the results, XRF shows excellent potential as a process control tool for waste glass vitrification. Glasses prepared for this study were further analyzed for durability by toxicity characteristic leaching procedure and product consistency test and results are presented

  17. Chemical properties and biodegradability of waste paper mill sludges to be used for landfill covering.

    Science.gov (United States)

    Zule, Janja; Cernec, Franc; Likon, Marko

    2007-12-01

    Waste paper mill sludges originating from different effluent treatment and de-inking installations are complex mixtures of inorganic and organic particles. Due to their favourable physico-chemical, and microbiological characteristics, they may be conveniently reused for different purposes as such or after appropriate pretreatment. Sludges from the Slovenian paper industry were extensively tested for their chemical, stability and sealing properties. During the biodegradability tests, evolutions of greenhouse gases CO2, CH4 and H2S as well as the concentrations of released volatile organic acids, such as acetic, propionic, butyric, lactic and glycollic acids as the typical degradation products of organic materials, were measured. Some other important parameters of water leachates such as pH, redox potential, content of starch and leachable ions were also evaluated. The results indicate that most of them can be efficiently applied as alternative hydraulic barrier layers for landfill construction and covering instead of the more expensive clay due to their good geomechanical properties, chemical inertness and microbiological stability. Such replacement brings about considerable economical and ecological benefits as the waste is reprocessed as secondary raw material. PMID:18229748

  18. Determination of long-lived fission products and actinides in Savannah River Site HLW sludge and glass for waste acceptance

    International Nuclear Information System (INIS)

    Savannah River Site (SRS) is immobilizing the radioactive, high-level waste sludge in Tank 51 into a borosilicate glass for disposal in a geologic repository. A requirement for repository acceptance is that SRS report the concentrations of certain fission product and actinide radionuclides in the glass. This paper presents measurements of many of these concentrations in both Tank 51 sludge and the final glass. The radionuclides were measured by inductively coupled plasma mass spectrometry and α, β, and γ counting methods. Examples of the radionuclides are 90Sr, 137Cs, 238U and , 239Pu. Concentrations in the glass are 3.1 times lower due to dilution of the sludge with a nonradioactive glass forming frit in the vitrification process. Results also indicated that in both the sludge and glass the relative concentrations of the long lived fission products insoluble in caustic are in proportion to their yields from the fission of 235U waste in the SRS reactors. This allowed the calculation of a fission yield scaling factor. This factor in addition to the sludge dilution factor can be used to estimate concentrations of waste acceptance radionuclides that cannot be measured in the glass. Examples of these radionuclides are 79Se, 93Zr, and 107Pd. (author)

  19. EFFECTS OF SOIL TREATMENT BY COAL MINING CARBONIFEROUS WASTE SLUDGE IN MAIZE GROWING

    Directory of Open Access Journals (Sweden)

    Robin Mujačić

    2011-11-01

    Full Text Available The multifuncional role and importance of organic matter in soil is widely known. It is also known that the organic matter in soil is subjected to microbiological-biochemical processes of transformation, which includes synthesis of humus as well as it’s decomposition -mineralization. Mineralization means transformation-decomposition of organic matter by microbiological processes to mineral products; plant nutrients and water + CO2 as starting and ending component of photosyntesis. Nutrients are partly plant available with fertilizing effect, partly lost from the soil - leaching in ground water, causing it’s eutrophication, but CO2 in atmosphere participates in greenhouse effect. Practically, mineralization means decreasing of organic matter content in soil and soil degradation [1,4]. In natural ecosystems (phytocenoses natural forests and meadows, it is almost a balanced between inflow and consumption of organic matter, while the cultural and anthropogenic soils agrobiocenosis in general, this relationship is disturbed that there is a disproportion between the inflow and loss [1,4]. Therefore, various materials that contains organic material (waste, various flotation, sludge, etc. are often used with more or less success. One of such materials, as well as the potential fertilizer, is carboniferous lake sludge like waste of coal mining sedimented at the bottom of the lake in huge quantities, which is the subject of our reasearch. The research were conducted to determine its fertilizing efects and value for repairing of physical and chemical properties of soil. The research refered to: -- Laboratory analysis of physical and chemical characteristics of the carboniferous sludge samples, -- Analysis of soil of the experimental field -- Research on heavy metals concentration in soil of the experimental farm and in carboniferous sludge, and Research of fertilizing effects of sludge, comparative mineral fertilizer and farmyard manure treatment by

  20. Influence of feeding mixture composition in batch anaerobic co-digestion of stabilized municipal sludge and waste from dairy farms.

    Science.gov (United States)

    Trulli, Ettore; Torretta, Vincenzo

    2015-01-01

    Waste anaerobic co-digestion applications are particularly useful in Southern Mediterranean areas where large quantities of agricultural waste materials and waste from agro-industries are produced. This waste can be added to urban waste together with the sludge produced by wastewater treatment processes, which, when combined, guarantee the supply of organic matrixes for treatment throughout the year. The implementation of facilities to service vast areas of the agricultural economy and which are heterogeneous in terms of production can provide a good solution. We present an experimental investigation into the anaerobic co-digestion of municipal sludge and bio-waste produced in the Mediterranean area. We conducted anaerobic treatability tests, with measures of biogas production and pH of the mixture in digestion. Our main aims were to identify an optimal mix of substrates for the production of biogas, and to analyse the influence on the composition of biogas and the variation in pH values of the substrates. This analysis was conducted considering the variation of the input, in particular due to the addition of waste acids, such as biological sewage sludge. PMID:25442095

  1. Conditioning of waste cladding hulls by eutectic melting and embedding in glass

    International Nuclear Information System (INIS)

    Radioactive zircaloy fuel cans were compacted by eutectic melting with copper. Decontamination of molten metal with a low melting point fluorinated slag was studied. Tritium release was also measured. Zircaboy fuel cans were embedded in glass by heating under argon atmosphere. Block obtained are monolithic and compact. Leaching ratio of metallic ingots are relatively high at ambient temperature, probably by galvanic corrosion due to copper. However alpha activity is lower than activity from conditioned wastes. Containment is poor for embedded wastes during first days of leaching due to the preparation process

  2. Fabrication of a Sludge-Conditioning System for processing legacy wastes from the Gunite and Associated Tanks

    International Nuclear Information System (INIS)

    The Sludge Conditioning System (SCS) for the Gunite and Associated Tanks (GAATs) is designed to receive, monitor, characterize and process legacy waste materials from the South Tank Farm tanks in preparation for final transfer of the wastes to the Melton Valley Storage Tanks (MVSTs), which are located at Oak Ridge National Laboratory. The SCS includes (1) a Primary Conditioning System (PCS) Enclosure for sampling and particle size classification, (2) a Solids Monitoring Test Loop (SMTL) for slurry characterization, (3) a Waste Transfer Pump to retrieve and transfer waste materials from GAAT consolidation tank W-9 to the MVSTs, (4) a PulsAir Mixing System to provide mixing of consolidated sludges for ease of retrieval, and (5) the interconnecting piping and valving. This report presents the design, fabrication, cost, and fabrication schedule information for the SCS

  3. Progress report for 1984/85 from the Waste Treatment and Disposal Working Party covering joint BNFL/DOE funded work

    International Nuclear Information System (INIS)

    The progress report from the waste treatment and disposal working party is concerned with the management of intermediate-level radioactive waste arising from dismantled fuel assemblies, cladding removed from fuel cans, sludges from fuel cladding corrosion, flocs from liquid waste, ion exchange resins and solid wastes generated during reprocessing. It is proposed that these wastes be incorporated in a matrix for safe transport, storage and disposal and the objectives of the study are to evaluate waste products arising from the treatment of ILWS and to develop techniques to check the quality of the finished waste product. (UK)

  4. Two-step upflow anaerobic sludge bed system for sewage treatment under subtropical conditions with posttreatment in waste stabilization ponds

    NARCIS (Netherlands)

    Seghezzo, L.; Trupiano, A.P.; Liberal, V.; Todd, P.G.; Figueroa, M.E.; Gutierrez, M.A.; Silva Wilches, Da A.C.; Iribarnegaray, M.; Guerra, R.G.; Arena, A.; Cuevas, C.M.; Zeeman, G.; Lettinga, G.

    2003-01-01

    A pilot-scale sewage treatment system consisting of two upflow anaerobic sludge bed (UASB) reactors followed by five waste stabilization ponds (WSPs) in series was studied under subtropical conditions. The first UASB reactor started up in only 1 mo (stable operation, high chemical oxygen demand [COD

  5. Sampling and analysis of radioactive liquid wastes and sludges in the Melton Valley and evaporator facility storage tanks at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Sears, M.B.; Botts, J.L.; Ceo, R.N.; Ferrada, J.J.; Griest, W.H.; Keller, J.M.; Schenley, R.L.

    1990-09-01

    The sampling and analysis of the radioactive liquid wastes and sludges in the Melton Valley Storage Tanks (MVSTs), as well as two of the evaporator service facility storage tanks at ORNL, are described. Aqueous samples of the supernatant liquid and composite samples of the sludges were analyzed for major constituents, radionuclides, total organic carbon, and metals listed as hazardous under the Resource Conservation and Recovery Act (RCRA). Liquid samples from five tanks and sludge samples from three tanks were analyzed for organic compounds on the Environmental Protection Agency (EPA) Target Compound List. Estimates were made of the inventory of liquid and sludge phases in the tanks. Descriptions of the sampling and analytical activities and tabulations of the results are included. The report provides data in support of the design of the proposed Waste Handling and Packaging Plant, the Liquid Low-Level Waste Solidification Project, and research and development activities (R D) activities in developing waste management alternatives. 7 refs., 8 figs., 16 tabs.

  6. 3.8. De-ironing of sludge, sifting of solid waste storage and products of their processing

    International Nuclear Information System (INIS)

    The de-ironing of sludge, sifting of solid waste storage and products of their processing by means of different methods, including the acid processing with extraction of iron-containing compounds into solution, alkaline de-ironing, and chlorination method was considered. The dependence of rate of iron and aluminium extraction on HCl concentration and temperature was studied.

  7. Co-digestion of cattle manure with food waste and sludge to increase biogas production

    International Nuclear Information System (INIS)

    Highlights: ► Small increase in methane production was observed applying sonication pretreatment. ► Biogas productions between 720 and 1100 mL/Lreactor day were achieved. ► Volatile solids removal efficiencies ranged between 53% and 60%. ► Lower methane yields were obtained when operating under thermophilic conditions. ► Optimum OLR in lab-scale CSTR was 1.2–1.3 g VS/L day (HRT: 20 days). - Abstract: Anaerobic co-digestion strategies are needed to enhance biogas production, especially when treating certain residues such as cattle/pig manure. This paper presents a study of co-digestion of cattle manure with food waste and sewage sludge. With the aim of maximising biogas yields, a series of experiments were carried out under mesophilic and thermophilic conditions using continuously stirred-tank reactors, operating at different hydraulic residence times. Pretreatment with ultrasound was also applied to compare the results with those obtained with non-pretreated waste. Specific methane production decreases when increasing the OLR and decreasing HRT. The maximum value obtained was 603 LCH4/kg VSfeed for the co-digestion of a mixture of 70% manure, 20% food waste and 10% sewage sludge (total solid concentration around 4%) at 36 °C, for an OLR of 1.2 g VS/L day. Increasing the OLR to 1.5 g VS/L day led to a decrease of around 20–28% in SMP. Lower methane yields were obtained when operating at 55 °C. The increase in methane production when applying ultrasound to the feed mixtures does not compensate for the energy spent in this pretreatment.

  8. Co-digestion of cattle manure with food waste and sludge to increase biogas production

    Energy Technology Data Exchange (ETDEWEB)

    Maranon, E., E-mail: emara@uniovi.es [Department of Chemical Engineering and Environmental Technology, University Institute of Technology of Asturias, Campus of Gijon, University of Oviedo, 33203 Gijon (Spain); Castrillon, L.; Quiroga, G.; Fernandez-Nava, Y. [Department of Chemical Engineering and Environmental Technology, University Institute of Technology of Asturias, Campus of Gijon, University of Oviedo, 33203 Gijon (Spain); Gomez, L.; Garcia, M.M. [Zero Emissions Technology, 41018 Seville (Spain)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Small increase in methane production was observed applying sonication pretreatment. Black-Right-Pointing-Pointer Biogas productions between 720 and 1100 mL/Lreactor day were achieved. Black-Right-Pointing-Pointer Volatile solids removal efficiencies ranged between 53% and 60%. Black-Right-Pointing-Pointer Lower methane yields were obtained when operating under thermophilic conditions. Black-Right-Pointing-Pointer Optimum OLR in lab-scale CSTR was 1.2-1.3 g VS/L day (HRT: 20 days). - Abstract: Anaerobic co-digestion strategies are needed to enhance biogas production, especially when treating certain residues such as cattle/pig manure. This paper presents a study of co-digestion of cattle manure with food waste and sewage sludge. With the aim of maximising biogas yields, a series of experiments were carried out under mesophilic and thermophilic conditions using continuously stirred-tank reactors, operating at different hydraulic residence times. Pretreatment with ultrasound was also applied to compare the results with those obtained with non-pretreated waste. Specific methane production decreases when increasing the OLR and decreasing HRT. The maximum value obtained was 603 LCH{sub 4}/kg VS{sub feed} for the co-digestion of a mixture of 70% manure, 20% food waste and 10% sewage sludge (total solid concentration around 4%) at 36 Degree-Sign C, for an OLR of 1.2 g VS/L day. Increasing the OLR to 1.5 g VS/L day led to a decrease of around 20-28% in SMP. Lower methane yields were obtained when operating at 55 Degree-Sign C. The increase in methane production when applying ultrasound to the feed mixtures does not compensate for the energy spent in this pretreatment.

  9. Production of Controlled Low Strength Material Utilizing Waste Paper Sludge Ash and Recycled Aggregate Concrete

    Directory of Open Access Journals (Sweden)

    Azmi A. N.

    2016-01-01

    Full Text Available Recently, the best method to make the concrete industry more sustainable was using the waste materials to replace the natural resources. Currently waste paper sludge is a major economic and environmental problem in this country. In this research, the alternative method is to dwindle the usage of natural resources and the usage of cement in the construction. This method is to replace the usage of cement with the waste paper sludge ash (WPSA and to use the recycle aggregate collected from the construction is used. The WPSA has ingredient likely cement such as self-cementation but for a low strength. The research was conducted at heavy laboratory UITM Pulau Pinang. Meanwhile, the WPSA is collected at MNI Industries at Mentakab, Pahang. The recycle aggregate is a separated half, which were fine aggregate and the coarse aggregate with the specific size. In this research, the ratio is divided into two (2 which is 1:1 and 1:2 for the aggregate and difference percentage levels of WPSA. The percentage levels of WPSA that use in this research are 10%, 20%, 30%, 40%, 50%, and 60%. A total of 36 cubes were prepared. Aim of this research is to develop a simple design approach for the mixture proportioning of WPSA and recycle concrete aggregate (RCA within the concrete and to assess the effect of concrete mix with different percentage of WPSA and RCA ratio on the properties. It is found that the best design mix that achieves control low strength material (CLSM is on 30% of WPSA with the ratio 1:2 on day 28 of compression test.

  10. Feasibility study of green wastes composting with digested and dewatering sludge from municipal wastewater treatment plant in Iran

    OpenAIRE

    Neamat Jaafarzadeh Haghighi Fard; Behnam Moradi; Mokhtar Abbasi; Rahman Alivar Babadi; Hossein Bahrani; Azadeh Mirzaie; Ahmad Zare Javid; Maryam Ravanbakhsh

    2015-01-01

    Background: Composting as a waste management technology is becoming more widespread. The purpose of this study was to assess the feasibility and to find the most effective composting process for the ratio of green waste, digested and dewatered sludge from Chonibieh wastewater treatment plant in the west region of Ahvaz. Methods: The composting time was 23 days and the evaluated parameters in this period of the study were organic carbon, total nitrogen, phosphorus, carbon to nitrogen ratio ...

  11. PLFAs of the microbial communities in composting mixtures of agro-industry sludge with different proportions of household waste

    OpenAIRE

    Amir, Soumia; Abouelwafa, Rajae; Meddich, Abdelilah; Souabi, Salah; Winterton, Peter; Merlina, Georges; Revel, Jean-Claude; Pinelli, Eric; Hafidi, Mohamed

    2010-01-01

    Phospholipid fatty acids (PLFAs) were analysed at different time periods during composting of two waste mixtures rich in fats, M1 (22%) and M2 (39%), with the aim of monitoring changes in microbial community structure. The two mixtures consisted of a sludge sample collected from a vegetable oil refinery effluent treatment plant combined with household wastes. The PLFA profiles of both mixtures revealed that, at the start of the process, fungi and Gram-negative bacteria (GÀ) were more abundant...

  12. Biomethane Production as an Alternative Bioenergy Source from Codigesters Treating Municipal Sludge and Organic Fraction of Municipal Solid Wastes

    OpenAIRE

    M. Evren Ersahin; Cigdem Yangin Gomec; R. Kaan Dereli; Osman Arikan; Izzet Ozturk

    2010-01-01

    Energy recovery potential of a mesophilic co-digester treating OFMSW and primary sludge at an integrated biomethanization plant was investigated based on feasibility study results. Since landfilling is still the main solid waste disposal method in Turkey, land scarcity will become one of the most important obstacles. Restrictions for biodegradable waste disposal to sanitary landfills in EU Landfill Directive and uncontrolled long-term contamination with gas emissions and leachate necessitate ...

  13. Transuranic Waste Processing Center (TWPC) Legacy Tank RH-TRU Sludge Processing and Compliance Strategy - 13255

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) needs to safely and efficiently treat its 'legacy' transuranic (TRU) waste and mixed low-level waste (LLW) from past research and defense activities at the Oak Ridge National Laboratory (ORNL) so that the waste is prepared for safe and secure disposal. The TWPC operates an Environmental Management (EM) waste processing facility on the Oak Ridge Reservation (ORR). The TWPC is classified as a Hazard Category 2, non-reactor nuclear facility. This facility receives, treats, and packages low-level waste and TRU waste stored at various facilities on the ORR for eventual off-site disposal at various DOE sites and commercial facilities. The Remote Handled TRU Waste Sludge held in the Melton Valley Storage Tanks (MVSTs) was produced as a result of the collection, treatment, and storage of liquid radioactive waste originating from the ORNL radiochemical processing and radioisotope production programs. The MVSTs contain most of the associated waste from the Gunite and Associated Tanks (GAAT) in the ORNL's Tank Farms in Bethel Valley and the sludge (SL) and associated waste from the Old Hydro-fracture Facility tanks and other Federal Facility Agreement (FFA) tanks. The SL Processing Facility Build-outs (SL-PFB) Project is integral to the EM cleanup mission at ORNL and is being accelerated by DOE to meet updated regulatory commitments in the Site Treatment Plan. To meet these commitments a Baseline (BL) Change Proposal (BCP) is being submitted to provide continued spending authority as the project re-initiation extends across fiscal year 2012 (FY2012) into fiscal year 2013. Future waste from the ORNL Building 3019 U-233 Disposition project, in the form of U-233 dissolved in nitric acid and water, down-blended with depleted uranyl nitrate solution is also expected to be transferred to the 7856 MVST Annex Facility (formally the Capacity Increase Project (CIP) Tanks) for co-processing with the SL. The SL-PFB project will construct and install

  14. Zero-valent iron enhanced methanogenic activity in anaerobic digestion of waste activated sludge after heat and alkali pretreatment.

    Science.gov (United States)

    Zhang, Yaobin; Feng, Yinghong; Quan, Xie

    2015-04-01

    Heat or alkali pretreatment is the effective method to improve hydrolysis of waste sludge and then enhance anaerobic sludge digestion. However the pretreatment may inactivate the methanogens in the sludge. In the present work, zero-valent iron (ZVI) was used to enhance the methanogenic activity in anaerobic sludge digester under two methanogens-suppressing conditions, i.e. heat-pretreatment and alkali condition respectively. With the addition of ZVI, the lag time of methane production was shortened, and the methane yield increased by 91.5% compared to the control group. The consumption of VFA was accelerated by ZVI, especially for acetate, indicating that the acetoclastic methanogenesis was enhanced. In the alkali-condition experiment, the hydrogen produced decreased from 27.6 to 18.8 mL when increasing the ZVI dosage from 0 to 10 g/L. Correspondingly, the methane yield increased from 1.9 to 32.2 mL, which meant that the H2-utilizing methanogenes was enriched. These results suggested that the addition of ZVI into anaerobic digestion of sludge after pretreated by the heat or alkali process could efficiently recover the methanogenic activity and increase the methane production and sludge reduction. PMID:25681947

  15. Verification Of The Defense Waste Processing Facility's (DWPF) Process Digestion Method For The Sludge Batch 7A Qualification Sample

    International Nuclear Information System (INIS)

    For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs confirmation of the applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples. DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICP-AES). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestions of Sludge Batch 7a (SB7a) SRAT Receipt and SB7a SRAT Product samples. The SB7a SRAT Receipt and SB7a SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constituates the SB7a Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 6 (SB6), to form the Sb7a Blend composition.

  16. [Bioleaching of fly ash from municipal solid waste incinerator using sewage sludge and pig manure as culture media].

    Science.gov (United States)

    Zhou, Shun-gui; Chang, Ming; Hu, Pei; Ni, Jin-ren

    2005-11-01

    A mixed culture of Acidihiobacillus ferrooaidans and Acidihiobacillus thiooxidans was used to leach heavy metals from municipal solid waste incineration fly ash (MSWI fly ash). This study explored the possibility of using sewage sludge or pig manure as nutrients for supporting the growth of the leaching bacteria and allowing metal solubilization like a synthetic mineral medium. In contrast to pig manure, there is a high ability for acidification of the fly ash and solubilization of toxic metals using sewage sludge at the same content. After 15 d of bioleaching, the following removal efficiencies were obtained for the treatment with the addition of 1% sewage sludge: Cd 88.1%; Zn 78.7%; Cu 69.6%, whereas their removal efficiencies for the treatment with the addition of 1% pig manure were 82.4%, 73.5% and 60.0%, respectively. Results demonstrate that the inhibition by sewage sludge DOM is much more significant than by pig manure DOM at the same concentration level. The dissolved organic carbon in excess of 400 and 150 mg/L was inhibitory to the bacterial growth using sludge DOM and manure DOM, respectively. Compared with sewage sludge, pig manure contained a higher fraction of DOM with molecular size <1000, which led to its higher toxicity. PMID:16447455

  17. Enhancement of thermophilic anaerobic digestion of thickened waste activated sludge by combined microwave and alkaline pretreatment

    Institute of Scientific and Technical Information of China (English)

    Yongzhi Chi; Yuyou Li; Xuening Fei; Shaopo Wang; Hongying Yun

    2011-01-01

    Pretreatment of thickened waste activated sludge (TWAS) by combined microwave and alkaline pretreatment (MAP) was studied to improve thermophilic anaerobic digestion efficiency.Uniform design was applied to determine the combination of target temperature (110-210℃),microwave holding time (1-51 min),and NaOH dose (0-2.5 g NaOH/g suspended solids (SS)) in terms of their effect on volatile suspended solids (VSS) solubilization.Maximum solubilization ratio (85.1%) of VSS was observed at 210℃ with 0.2 g-NaOH/g-SS and 35 min holding time.The effects of 12 different pretreatment methods were investigated in 28 thermophilic batch reactors by monitoring cumulative methane production (CMP).Improvements in methane production in the TWAS were directly related to the microwave and alkaline pretreatment of the sludge.The highest CMP was a 27% improvement over the control.In spite of the increase in soluble chemical oxygen demand concentration and the decrease in dewaterability of digested sludge,a semi-continuous thennophilic reactor fed with pretreated TWAS without neutralization (at 170℃ with 1 rain holding time and 0.05 g NaOH/g SS) was stable and functioned well,with volatile solid (VS) and total chemical oxygen demand (TCOD) reductions of 28% and 18%,respectively,which were higher than those of the control system.Additionally,methane yields (L@STP/g-CODadded,at standard temperature and pressure (STP) conditions of 0℃ and 101.325 kPa) and (L@STP/g VSadded) increased by 17% and 13%,respectively,compared to the control reactor.

  18. Determination of long-lived fission products and actinides in Savannah River site HLW sludge and glass for waste acceptance

    International Nuclear Information System (INIS)

    Savannah River Site (SRS) is currently immobilizing the radioactive, caustic, high-level waste sludge in Tank 51 into a borosilicate glass for disposal in a geologic repository. A requirement for repository acceptance is that SRS report the concentrations of certain fission product and actinide radionuclides in the glass. This paper presents measurements of many of these concentrations in both Tank 51 sludge and the final glass. The radionuclides were measured by inductively coupled plasma - mass spectrometry and α, β, and γ counting methods. Examples of the radionuclides are Sr-90, Cs-137, U-238, Pu-239, and Cm-244. Concentrations in the glass are 3.1 times lower due to dilution of the sludge with a nonradioactive glass forming frit in the vitrification process. Results also indicated that in both the sludge and glass the relative concentrations of the long lived fission products insoluble in caustic area in proportion to their yields from the fission of U-235 in the SRS reactors. This allowed the calculation of a fission yield scaling factor. This factor in addition to the sludge dilution factor can be used to estimate concentrations of waste acceptance radionuclides that cannot be measured in the glass

  19. Combined electrical-alkali pretreatment to increase the anaerobic hydrolysis rate of waste activated sludge during anaerobic digestion

    International Nuclear Information System (INIS)

    Highlights: • Combined electrical-alkali pretreatment for improving sludge anaerobic digestion was proposed. • Combined process enhanced the cell lysis, biopolymers releases, and thus sludge disintegration. • Increased solubilization of sludge increased the anaerobic hydrolysis rate. • Increased solubilization does not always induce an improved anaerobic digestion efficiency. - Abstract: Pretreatment can be used prior to anaerobic digestion to improve the efficiency of waste activated sludge (WAS) digestion. In this study, electrolysis and a commonly used pretreatment method of alkaline (NaOH) solubilization were integrated as a pretreatment method for promoting WAS anaerobic digestion. Pretreatment effectiveness of combined process were investigated in terms of disintegration degree (DDSCOD), suspended solids (TSS and VSS) removals, the releases of protein (PN) and polysaccharide (PS), and subsequent anaerobic digestion as well as dewaterability after digestion. Electrolysis was able to crack the microbial cells trapped in sludge gels and release the biopolymers (PN and PS) due to the cooperation of alkaline solubilization, enhancing the sludge floc disintegration/solubilization, which was confirmed by scanning electron microscopy (SEM) analysis. Biochemical methane potential (BMP) assays showed the highest methane yield was achieved with 5 V plus pH 9.2 pretreatment with up to 20.3% improvement over the non-pretreated sludge after 42 days of mesophilic operation. In contrast, no discernible improvements on anaerobic degradability were observed for the rest of pretreated sludges, probably due to the overmuch leakage of refractory soluble organics, partial chemical mineralization of solubilized compounds and sodium inhibition. The statistical analysis further indicated that increased solubilization induced by electrical-alkali pretreatment increased the first-order anaerobic hydrolysis rate (khyd), but had no, or very slight enhancement on WAS ultimate

  20. Laboratory Scale Study of Activated Sludge Process in Jet Loop Reactor for Waste WaterTreatment

    Directory of Open Access Journals (Sweden)

    M. S. Patil

    2014-03-01

    Full Text Available The present study was undertaken to evaluate the feasibility of Activated Sludge Process (ASP for the treatment of synthetic wastewater and to develop a simple design criteria under local conditions.A laboratory scale Compact jet loop reactor model comprising of an aeration tank and final clarifier was used for this purpose.Settled synthetic wastewater was used as influent to the aeration tank. The Chemical Oxygen Demand (COD of the influent and effluent was measured to find process efficiency at various mixed liquorvolatile suspended solids (MLVSS and hydraulic retention time (θ. The results of the studydemonstrated that an efficiency of above 95% could be obtained for COD if the ASP is operated atan MLVSS concentration of 3000 mg/L keeping an aeration time of 1 hour.In the present investigation the preliminary studies were carried out in a lab scale Jet loop reactor made of glass. Synthetic waste water having a composition of 1000 mg/L mixed with other nutrients such as Urea, Primary and secondary Potassium phosphates, Magnesium sulfate, Iron chloriderequired for the bacteria was prepared in the laboratory and reduction in COD and the increase inSuspended Solids (SSand the Sludge Volume Index (SVI were determined.

  1. Energy efficiency in waste water treatments plants: Optimization of activated sludge process coupled with anaerobic digestion

    International Nuclear Information System (INIS)

    This paper presents a study concerning the optimization of a Waste Water Treatment process. The process deals with carbon and nitrogen removal and includes activated sludge reactors coupled with an anaerobic digestion reactor. Nitrification and de-nitrification biochemical reactions are due to the biological activity of heterotrophic and autotrophic micro-organisms occurring inside the reactors. Rigorous Plant-Wide models that represent the main biochemical transformations have been constructed as per the CEIT approach . The energy consumption for each Physical Unit Operation (P.U.O.) involved in the flow-sheet is evaluated and a full link is made between the biological activity and the electrical demand or production. Steady-state mathematical optimizations are then computed and the influence of primary settling efficiency on electrical autonomy is quantified and demonstrated. The ammonium recycling from digestion to activated sludge reactors is also demonstrated to be a limiting factor for the overall energy efficiency, as well as the C-substrate availability for denitrifying. Some conclusions are then drawn to improve the global electrical efficiency of the system.

  2. Radioactivity in Oily Sludge and Produced Waste Water from Oil: Environmental Concerns and Potential Remedial Measures

    Directory of Open Access Journals (Sweden)

    Avin E. Pillay

    2010-03-01

    Full Text Available Produced water separated from oil is usually returned to the environment and could permeate through the water table. If such water is contaminated with radioactive substances, it could create a definite threat to the water supply, especially in arid regions where ground water and overhead streams are sources of potable water. Low-level radioactive contamination of oily sludge is equally hazardous and also leads to detrimental pollution of water resources. We investigated the distribution of 226Ra, 40K and 228Ac in produced waste water and oily sludge and found abnormal levels of radioactivity. A total of 90 ground wastewater samples were collected from different sites for a period of one year. The presence of these radionuclides was identified by their characteristic gamma rays. The detection system consisted of a high-purity germanium detector. Our results show that about 20% of the samples exhibited 20–60 Bq/L radioactivity and ~6% of the samples exceeded 60 Bq/L. Roughly 70% of the experimental samples fell in the range of 2–20 Bq/L, which still exceeded the maximum admissible drinking-water limit 0.2 Bq/L.

  3. Remove and recover phosphorus during anaerobic digestion of excess sludge by adding waste iron scrap

    Directory of Open Access Journals (Sweden)

    Zheng Wei

    2013-01-01

    Full Text Available In the current investigation, the feasibility of phosphorus removal in the anaerobic digestion of excess sludge by adding waste iron scrap (WIS was studied. The results show that the removal efficiency of phosphorus increases with the amount of WIS, and the maximum removal efficiency could reach 39%, 93% and 99% at WIS dosages of 1, 2 and 3 g/L, respectively. Sterilization greatly decreases the removal efficiency of phosphorus, having only -6%, 53% and 64% at WIS dosages of 1, 2 and 3 g/L, respectively. This means that iron-reducing bacteria and hydrolytic bacteria enhance 45%, 40% and 35% of phosphorus removal at WIS dosages of 1, 2 and 3 g/L, respectively. The first and the most important mechanism of phosphorus removal using WIS is hydrolytic bacteria, which reduce the pH of sludge to corrode the WIS, followed by precipitation of phosphorus by ferrous iron generated from the iron-reducing bacteria. Phosphorus adsorption onto the WIS is the second probable mechanism. The removed phosphorus is recovered up to 56% using magnet. This method is characterized by high removal efficiency, easy and steady operation, low cost, recovery and reuse, making it better than other physical and chemical treatments.

  4. Co-combustion of sewage sludge and energy-rich waste fuels or forest fuels; Sameldning av roetslam och energirika avfallsbraenslen eller skogsbraenslen

    Energy Technology Data Exchange (ETDEWEB)

    Linder, Kristina [TPS Termiska Processer AB, Nykoeping (Sweden)

    2003-10-01

    In this report literature on incineration of sewage sludge is summarises. In Sweden there is a yearly production of about 0,24 million-ton dry sewage sludge of which 50% is deposited. Recent changes in legislation will restrict and later prohibit the dumping of sewage sludge. Alternative methods for handling the material have not yet been found. In other parts of Europe the problem has been solved by incineration. Sludge incineration can be performed in several ways depending of the pretreatment. The sludge can be raw or digested, dewatered or dried. The sludge can be burnt as single fuel or in mixtures with other fuels. Focus in this work has been on co-combustion with biofuel or waste, as it will make use of existing plants. Digested sludge is also of major interest as 70% of the Swedish sludge is digested. The report describes the situation both in Sweden and in the rest of Europe. Sludge has a varying quality depending on origin and treatment, which affects the combustion properties. Ash and moisture contents differ from other fuels. The heating value of sewage sludge is approximately 20 MJ/kg per dry combustible matter and the amount of organic is around 70%. Compared to forest residue and demolition wood, sludge contains high levels of nitrogen and sulphur, which will cause emissions. The nitrogen level is about 10 times higher and the sulphur level 25 to 50 times higher. Sulphur, in combination with alkali metals, can cause deposit problems in boilers. However, sludge contains low levels of alkali. In the experimental investigation leaching of digested sludge showed low values on water conductivity which indicates a low concentration of sintering ash species in the sludge. A comparison of the aerodynamic properties of dried digested sludge and wood chips from energy coppice showed that sludge has a lower fraction of fines. This indicates that the sewage sludge is not likely to be carried over in the furnace but rather to stay in the fuel and ash bed on the

  5. Ecotoxicological tests for detection of toxicity in waste waters, sludges and solid wastes

    Czech Academy of Sciences Publication Activity Database

    Maršálek, Blahoslav

    Vol. 1. Tehran: PR Commitee of Asian Conference on Water and Waste water Management, 1998, s. 141-145. [Asian Conference on Water and Waste water Management. Teheran (IR), 02.03.1998-04.03.1998] Subject RIV: EE - Microbiology, Virology

  6. Volatile fatty acids produced by co-fermentation of waste activated sludge and henna plant biomass.

    Science.gov (United States)

    Huang, Jingang; Zhou, Rongbing; Chen, Jianjun; Han, Wei; Chen, Yi; Wen, Yue; Tang, Junhong

    2016-07-01

    Anaerobic co-fermentation of waste activated sludge (WAS) and henna plant biomass (HPB) for the enhanced production of volatile fatty acids (VFAs) was investigated. The results indicated that VFAs was the main constituents of the released organics; the accumulation of VFAs was much higher than that of soluble carbohydrates and proteins. HPB was an advantageous substrate compared to WAS for VFAs production; and the maximum VFAs concentration in an HPB mono-fermentation system was about 2.6-fold that in a WAS mono-fermentation system. In co-fermentation systems, VFAs accumulation was positively related to the proportion of HPB in the mixed substrate, and the accumulated VFAs concentrations doubled when HPB was increased from 25% to 75%. HPB not only adjust the C/N ratio; the associated and/or released lawsone might also have a positive electron-shuttling effect on VFAs production. PMID:27003793

  7. Microbiological characterization and specific methanogenic activity of anaerobe sludges used in urban solid waste treatment

    International Nuclear Information System (INIS)

    This study presents the microbiological characterization of the anaerobic sludge used in a two-stage anaerobic reactor for the treatment of organic fraction of urban solid waste (OFUSW). This treatment is one alternative for reducing solid waste in landfills at the same time producing a biogas (CH4 and CO2) and an effluent that can be used as biofertilizer. The system was inoculated with sludge from a wastewater treatment plant (WWTP) (Rio Frio Plant in Bucaramanga-Colombia) and a methanogenic anaerobic digester for the treatment of pig manure (Mesa de los Santos in Santander). Bacterial populations were evaluated by counting groups related to oxygen sensitivity, while metabolic groups were determined by most probable number (MPN) technique. Specific methanogenic activity (SMA) for acetate, formate, methanol and ethanol substrates was also determined. In the acidogenic reactor (R1), volatile fatty acids (VFA) reached values of 25,000 mg L-1 and a concentration of CO2 of 90%. In this reactor, the fermentative population was predominant (105-106 MPN mL-1). The acetogenic population was (105 MPN mL-1) and the sulphate-reducing population was (104-105 MPN mL-1). In the methanogenic reactor (R2), levels of CH4 (70%) were higher than CO2 (25%), whereas the VFA values were lower than 4000 mg L-1. Substrate competition between sulphate-reducing (104-105 MPN mL-1) and methanogenic bacteria (105 MPN mL-1) was not detected. From the SMA results obtained, acetoclastic (2.39 g COD-CH4 g-1 VSS-1 day-1) and hydrogenophilic (0.94 g COD-CH4 g-1 VSS-1 day-1) transformations as possible metabolic pathways used by methanogenic bacteria is suggested from the SMA results obtained. Methanotrix sp., Methanosarcina sp., Methanoccocus sp. and Methanobacterium sp. were identified

  8. Actual-Waste Testing Of Ultraviolet Light To Augment The Enhanced Chemical Cleaning Of SRS Sludge

    International Nuclear Information System (INIS)

    In support of Savannah River Site (SRS) tank closure efforts, the Savannah River National Laboratory (SRNL) conducted Real Waste Testing (RWT) to evaluate Enhanced Chemical Cleaning (ECC), an alternative to the baseline 8 wt% oxalic acid (OA) chemical cleaning technology for tank sludge heel removal. ECC utilizes a more dilute OA solution (2 wt%) and an oxalate destruction technology using ozonolysis with or without the application of ultraviolet (UV) light. SRNL conducted tests of the ECC process using actual SRS waste material from Tanks 5F and 12H. The previous phase of testing involved testing of all phases of the ECC process (sludge dissolution, OA decomposition, product evaporation, and deposition tank storage) but did not involve the use of UV light in OA decomposition. The new phase of testing documented in this report focused on the use of UV light to assist OA decomposition, but involved only the OA decomposition and deposition tank portions of the process. Compared with the previous testing at analogous conditions without UV light, OA decomposition with the use of UV light generally reduced time required to reach the target of <100 mg/L oxalate. This effect was the most pronounced during the initial part of the decomposition batches, when pH was <4. For the later stages of each OA decomposition batch, the increase in OA decomposition rate with use of the UV light appeared to be minimal. Testing of the deposition tank storage of the ECC product resulted in analogous soluble concentrations regardless of the use or non-use of UV light in the ECC reactor.

  9. ACTUAL-WASTE TESTING OF ULTRAVIOLET LIGHT TO AUGMENT THE ENHANCED CHEMICAL CLEANING OF SRS SLUDGE

    Energy Technology Data Exchange (ETDEWEB)

    Martino, C.; King, W.; Ketusky, E.

    2012-07-10

    In support of Savannah River Site (SRS) tank closure efforts, the Savannah River National Laboratory (SRNL) conducted Real Waste Testing (RWT) to evaluate Enhanced Chemical Cleaning (ECC), an alternative to the baseline 8 wt% oxalic acid (OA) chemical cleaning technology for tank sludge heel removal. ECC utilizes a more dilute OA solution (2 wt%) and an oxalate destruction technology using ozonolysis with or without the application of ultraviolet (UV) light. SRNL conducted tests of the ECC process using actual SRS waste material from Tanks 5F and 12H. The previous phase of testing involved testing of all phases of the ECC process (sludge dissolution, OA decomposition, product evaporation, and deposition tank storage) but did not involve the use of UV light in OA decomposition. The new phase of testing documented in this report focused on the use of UV light to assist OA decomposition, but involved only the OA decomposition and deposition tank portions of the process. Compared with the previous testing at analogous conditions without UV light, OA decomposition with the use of UV light generally reduced time required to reach the target of <100 mg/L oxalate. This effect was the most pronounced during the initial part of the decomposition batches, when pH was <4. For the later stages of each OA decomposition batch, the increase in OA decomposition rate with use of the UV light appeared to be minimal. Testing of the deposition tank storage of the ECC product resulted in analogous soluble concentrations regardless of the use or non-use of UV light in the ECC reactor.

  10. Co-digestion of food and garden waste with mixed sludge from wastewater treatment in continuously stirred tank reactors

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Boldrin, Alessio; Boe, Kanokwan;

    2016-01-01

    Co-digestions of urban organic waste were conducted to investigate the effect of the mixing ratio between sludge, food waste, grass clippings and green waste at different hydraulic retention times (HRTs). Compared to the digestion of 100% sludge, the methane yield increased by 48% and 35%, when co......-digesting sludge with food waste, grass clippings and garden waste with a corresponding % VS of 10:67.5:15.75:6.75 (R1) and 10:45:31.5:13.5 (R2), respectively. The methane yield remained constant at around 425 and 385 NmL CH4/g VS in R1 and R2, respectively, when the reactors were operated at HRTs of 15, 20 and 30...... days. However, the methane yield dropped significantly to 356 (R1) and 315 (R2) NmL CH4/g VS when reducing the HRT to 10 days, indicating that the process was stressed. Since the methane production rate improved significantly with decreasing HRT, the trade-off between yield and productivity was...

  11. Co-digestion of food and garden waste with mixed sludge from wastewater treatment in continuously stirred tank reactors.

    Science.gov (United States)

    Fitamo, T; Boldrin, A; Boe, K; Angelidaki, I; Scheutz, C

    2016-04-01

    Co-digestions of urban organic waste were conducted to investigate the effect of the mixing ratio between sludge, food waste, grass clippings and green waste at different hydraulic retention times (HRTs). Compared to the digestion of 100% sludge, the methane yield increased by 48% and 35%, when co-digesting sludge with food waste, grass clippings and garden waste with a corresponding %VS of 10:67.5:15.75:6.75 (R1) and 10:45:31.5:13.5 (R2), respectively. The methane yield remained constant at around 425 and 385 NmL CH4/g VS in R1 and R2, respectively, when the reactors were operated at HRTs of 15, 20 and 30 days. However, the methane yield dropped significantly to 356 (R1) and 315 (R2) NmL CH4/g VS when reducing the HRT to 10 days, indicating that the process was stressed. Since the methane production rate improved significantly with decreasing HRT, the trade-off between yield and productivity was obtained at 15 days HRT. PMID:26866760

  12. Recycling of blast furnace sludge by briquetting with starch binder: Waste gas from thermal treatment utilizable as a fuel.

    Science.gov (United States)

    Drobíková, Klára; Plachá, Daniela; Motyka, Oldřich; Gabor, Roman; Kutláková, Kateřina Mamulová; Vallová, Silvie; Seidlerová, Jana

    2016-02-01

    Steel plants generate significant amounts of wastes such as sludge, slag, and dust. Blast furnace sludge is a fine-grained waste characterized as hazardous and affecting the environment negatively. Briquetting is one of the possible ways of recycling of this waste while the formed briquettes serve as a feed material to the blast furnace. Several binders, both organic and inorganic, had been assessed, however, only the solid product had been analysed. The aim of this study was to assess the possibilities of briquetting using commonly available laundry starch as a binder while evaluating the possible utilization of the waste gas originating from the thermal treatment of the briquettes. Briquettes (100g) were formed with the admixture of starch (UNIPRET) and their mechanical properties were analysed. Consequently, they were subjected to thermal treatment of 900, 1000 and 1100°C with retention period of 40min during which was the waste gas collected and its content analysed using gas chromatography. Dependency of the concentration of the compounds forming the waste gas on the temperature used was determined using Principal component analysis (PCA) and correlation matrix. Starch was found to be a very good binder and reduction agent, it was confirmed that metallic iron was formed during the thermal treatment. Approximately 20l of waste gas was obtained from the treatment of one briquette; main compounds were methane and hydrogen rendering the waste gas utilizable as a fuel while the greatest yield was during the lowest temperatures. Preparation of blast furnace sludge briquettes using starch as a binder and their thermal treatment represents a suitable method for recycling of this type of metallurgical waste. Moreover, the composition of the resulting gas is favourable for its use as a fuel. PMID:26684056

  13. DETERMINATION OF ACTIVATED SLUDGE MODEL ASDM PARAMETERS FOR WASTE WATER TREATMENT PLANT OPERATING IN THE SEQUENTIAL–FLOW TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Dariusz Zdebik

    2015-01-01

    Full Text Available This paper presents a method for calibration of activated sludge model with the use of computer program BioWin. Computer scheme has been developed on the basis of waste water treatment plant operating in the sequential – flow technology. For calibration of the activated sludge model data of influent and treated effluent from the existing object were used. As a result of conducted analysis was a change in biokinetic model and kinetic parameters parameters of wastewater treatment facilities. The presented method of study of the selected parameters impact on the activated sludge biokinetic model (including autotrophs maximum growth rate, the share of organic slurry in suspension general operational, efficiency secondary settling tanks can be used for conducting simulation studies of other treatment plants.

  14. Recovering metals from sewage sludge, waste incineration residues and similar substances with hyperaccumulative plants

    Science.gov (United States)

    Kisser, Johannes; Gattringer, Heinz; Iordanopoulos-Kisser, Monika

    2015-04-01

    Sewage sludges as well as ashes from waste incineration plants are known accumulation sinks of many elements that are either important nutrients for biological organisms (phosphorus, potassium, magnesium, etc.) or valuable metals when considered on their own in pure form (nickel, chrome, zinc, etc.); they are also serious pollutants when they occur in wild mixtures at localized anthropogenic end- of-stream points. Austria and many other countries have to import up to 90% of the material inputs of metals from abroad. These primary resources are becoming more expensive as they become more scarce and remaining deposits more difficult to mine, which is a serious concern for industrialized nations. Basic economic and strategic reasoning demands an increase in recycling activities and waste minimization. Technologies to recover metals in a reasonable and economically relevant manner from very diffuse sources are practically non-existent or require large amounts of energy and chemicals, which pose environmental risks. On the other hand agriculture uses large volumes of mineral fertilizers, which are often sourced from mines as well, and thus are also subject to the same principle of finiteness and potential shortage in supply. These converted biological nutrients are taken up by crops and through the food chain and human consumption end up in sewage systems and in wastewater treatment plants in great quantities. The metabolized nutrients mostly do not return to agriculture, but due to contamination with heavy metals are diverted to be used as construction aggregates or are thermally treated and end up rather uselessly in landfills. The project BIO-ORE aimed to explore new pathways to concentrate metals from diluted sources such as sewage sludge and wastewater by using highly efficient biological absorption and transport mechanisms. These enzymatic systems from plants work with very little energy input. The process is called bioaccumulation and can be most effectively

  15. Exploring the Reuse Potential of Chemical Sludge from Textile Wastewater Treatment Plants in India-A Hazardous Waste

    Directory of Open Access Journals (Sweden)

    Hema Patel

    2009-01-01

    Full Text Available Problem statement: This study was conducted to explore the reuse potential of the chemical sludge (considered as hazardous waste as per Indian Government Hazardous Waste Management Rules generated from combined effluent treatment in textile clusters. These textile clusters mainly cover the cotton dyeing and printing operations. Approach: Therefore, treatability studies of chemical sludge were conducted using solidification/stabilization treatment to examine the possibility of its reuse in construction materials. The sludge was characterised for its physico-chemical parameters and heavy metals. Standard blocks of dimensions 70.6×70.6×70.6 mm were prepared, in which chemical sludge was used as a partial replacement of cement by mixing 30-70 % of sludge in cement. After the experimental curing, the blocks were evaluated for physical engineering properties such as hardening time, block density, unconfined compressive strength. The chemical properties were determined in terms of concentrations of heavy metals in the TCLP leachate. Results: The hardening time ranged between 30-45 h. The compressive strength in the sludge cement blocks ranged from 2.63-22.54 N mm-2 after 14 days of water curing and 6.48-24.89 N mmm-2 after 28 days of water curing for 30, 40, 50, 60 and 70 % sludge replacement in cement. The block density varied between 1361. 3408-1813.8992 Kg m-3 after 14 days and 1386.3953-1842.3446 Kg m-3 after 28 days of water curing. The concentrations of heavy metals were negligible in the TCLP leachate and thus below USEPA regulatory limits. Conclusion/Recommendations: As far as structural applications is concerned, it is fulfilling the criteria of some of the classes (C to K as per the BIS standards of the bricks upto a strength of 25 N mm2. The use of sludge can definitely be explored for other structural and non-structural applications depending upon strength requirement. Other applications of textile sludge in the construction materials

  16. HYDROLYSIS AND METHANOGENIC PHASE OF ANAEROBIC DIGESTION OF SEWAGE SLUDGE AND URBAN SOLID WASTE = HIDRÓLISIS Y FASE METANOGÉNICA DE LA DIGESTIÓN ANAEROBIA DE LODOS DE DEPURADORA Y RESIDUOS SÓLIDOS URBANOS

    OpenAIRE

    Tânia Forster Carneiro; Montserrat Pérez

    2012-01-01

    This paper presents and discusses the feasibility of the mesophilic anaerobic digestion of the sewage sludge and urban solid waste. The experiment consists in the implementation of anaerobic reactors for sewage sludge operating under mesophilic (35º C) and semi-continuous (TRS 30 and 20 days) and using two different sources of inoculum (30% inoculation) and digested sludge urban waste. The thermal effects, chemical, physical and biological treatment of sewage sludge and MSW to methane and car...

  17. Physicochemical characterization of sewage sludge and green waste for agricultural utilization.

    Science.gov (United States)

    Ramdani, N; Hamou, A; Lousdad, A; Al-Douri, Y

    2015-01-01

    In order to valorize the organic wastes, a mixture composed of 60 kg of thick sewage sludge from a wastewater treatment plant, 30 kg of green wastes (made of 10 kg straw of wheat, 10 kg manure farm wastes, and 10 kg of dead leaves), and 10 kg of wood chips was prepared. The organic wastes were mixed and put into a wooden cubic composter having a volume of 1.5 m3. Physicochemical analyses were made every 30 days for five months. The results of the analyses showed that the obtained compost had good physicochemical quality and can be used as an organic fertilizer. The main characteristics of this compost were distinguished by its pH from 7.4 to 7.8, with a ratio of organic matter of 40-42%. During composting, the humification process led to an increase in humic acids from 29.5 to 39.1 mg g(-1), a decrease in fulvic acids from 32.1 to 10.9 mg g(-1), and a global decomposition of hemicellulose, cellulose, and lignin. The obtained results show that a period of 150 days of composting gave a C/N ratio of 15.4. The total metal content in the final compost was much lower than the standard toxic levels for composts to be used as good soil fertilizers. The germination index for the two plants Cicer arietinum and Hordeum vulgare was 93% after the same period of composting, showing that the final compost was not phytotoxic. The study showed the possibility of valorization of the compost and its possible use in the domain of agriculture. PMID:25517858

  18. Pilot tests of microbe-soil combined treatment of waste drilling sludge

    Directory of Open Access Journals (Sweden)

    Lirong Chen

    2015-03-01

    Full Text Available Microbe-soil combined treatment is a newly developed technology in view of the defects of the curing process and waste drilling mud slag properties. In particular, 0.3%–0.5% bioremediation reagents were fully mixed with the waste drilling sludge according to its wet and dry degree, and 1.5 folds to twice weight of more finely ground soil was added in the mix, which was covered by soil of 5–15 cm thick and thereby grasses or greeneries were planted on the soil. The process was successfully applied to some fields of Well Danqian 001-8, Well Lianhua 000-X8, etc. After three months of such treatment, the main indexes of the drilling solid waste such as the degradation of COD and the oil-degrading ratio reached more than 90%, the index of leaching solution met the requirement of the first grade in the national “Integrated Wastewater Discharge Standard”; heavy metal ion concentration in soil did not change significantly with the indicators meeting the requirement of the third grade in the national “Soil Environmental Quality Standard” (Dry Land; and no harmful effects of heavy metals have ever been found on the planted grasses and greeneries. In conclusion, with this microbe-soil technology, the soil property will recover its background values without any other chemical additives, realizing the ecological restoration and reuse of land covered by wellsite wastes, so it is in line with the energy-saving and environmentally-friendly treatment way.

  19. Comparison of ozone and thermal hydrolysis combined with anaerobic digestion for municipal and pharmaceutical waste sludge with tetracycline resistance genes.

    Science.gov (United States)

    Pei, Jin; Yao, Hong; Wang, Hui; Ren, Jia; Yu, Xiaohua

    2016-08-01

    Biosolids from wastewater treatment plant (WWTP) are environmental reservoirs of antibiotic resistance genes, which attract great concerns on their efficient treatments. Anaerobic digestion (AD) is widely used for sewage sludge treatment but its effectiveness is limited due to the slow hydrolysis. Ozone and thermal hydrolysis pre-treatment were employed to improve AD efficiency and reduce antibiotic-resistant genes in municipal and pharmaceutical waste sludge (MWS and PWS, respectively) in this study. Sludge solubilization achieved 15.75-25.09% and 14.85-33.92% after ozone and thermal hydrolysis, respectively. Both pre-treatments improved cumulative methane production and the enhancements were greater on PWS than MWS. Five tetracycline-resistant genes (tet(A), tet(G), tet(Q), tet(W), tet(X)) and one mobile element (intI1) were qPCR to assess pre-treatments. AD of pre-treated sludge reduced more tet genes than raw sludge for both ozonation and thermal hydrolysis in PWS and MWS. Thermal hydrolysis pre-treatment was more efficient than ozone for reduction after AD. Results of this study help support management options for reducing the spread of antibiotic resistance from biosolids. PMID:27151286

  20. Alternative treatment for septic tank sludge: co-digestion with municipal solid waste in bioreactor landfill simulators.

    Science.gov (United States)

    Valencia, R; den Hamer, D; Komboi, J; Lubberding, H J; Gijzen, H J

    2009-02-01

    Co-disposal of septic tank sludge had a positive effect on the municipal solid waste (MSW) stabilisation process in Bioreactor Landfill simulators. Co-disposal experiments were carried out using the Bioreactor Landfill approach aiming to solve the environmental problems caused by indiscriminate and inadequate disposal of MSW and especially of septic tank sludge. The simulator receiving septic tank sludge exhibited a 200 days shorter lag-phase as compared to the 350 days required by the control simulator to start the exponential biogas production. Additionally, the simulator with septic sludge apparently retained more moisture (>60% w/w), which enhanced the overall conversion of organic matter hence increasing the biogas production (0.60 m3 biogas kg(-1)VS(converted)) and removal efficiency of 60% for VS from the simulator. Alkaline pH values (pH>8.5) did not inhibit the biogas production; moreover it contributed to reduce partially the negative effects of NH(4)(+) (>2 g L(-1)) due to NH(3) volatilisation thus reducing the nitrogen content of the residues. Associated risks and hazards with septage disposal were practically eliminated as total coliform and faecal coliform contents were reduced by 99% and 100%, respectively at the end of the experiment. These results indicate that co-disposal has two direct benefits, including the safe and environmentally sound disposal of septic tank sludge and an improvement of the overall performance of the Bioreactor Landfill by increasing moisture retention and supplying a more acclimatised bacterial population. PMID:18400366

  1. Carbon capture and biogas enhancement by carbon dioxide enrichment of anaerobic digesters treating sewage sludge or food waste.

    Science.gov (United States)

    Bajón Fernández, Y; Soares, A; Villa, R; Vale, P; Cartmell, E

    2014-05-01

    The increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9 M fractions into batch ADs treating food waste or sewage sludge. Daily specific methane (CH4) production increased 11-16% for food waste and 96-138% for sewage sludge over the first 24h. Potential CO2 reductions of 8-34% for sewage sludge and 3-11% for food waste were estimated. The capacity of ADs to utilise additional CO2 was demonstrated, which could provide a potential solution for onsite sequestration of CO2 streams while enhancing renewable energy production. PMID:24632434

  2. Initial Cladding Condition

    International Nuclear Information System (INIS)

    The purpose of this analysis is to describe the condition of commercial Zircaloy clad fuel as it is received at the Yucca Mountain Project (YMP) site. Most commercial nuclear fuel is encased in Zircaloy cladding. This analysis is developed to describe cladding degradation from the expected failure modes. This includes reactor operation impacts including incipient failures, potential degradation after reactor operation during spent fuel storage in pool and dry storage and impacts due to transportation. Degradation modes include cladding creep, and delayed hydride cracking during dry storage and transportation. Mechanical stresses from fuel handling and transportation vibrations are also included. This Analysis and Model Report (AMR) does not address any potential damage to assemblies that might occur at the YMP surface facilities. Ranges and uncertainties have been defined. This analysis will be the initial boundary condition for the analysis of cladding degradation inside the repository. In accordance with AP-2.13Q, ''Technical Product Development Planning'', a work plan (CRWMS M andO 2000c) was developed, issued, and utilized in the preparation of this document. There are constraints, caveats and limitations to this analysis. This cladding degradation analysis is based on commercial Pressurized Water Reactor (PWR) fuel with Zircaloy cladding but is applicable to Boiling Water Reactor (BWR) fuel. Reactor operating experience for both PWRs and BWRs is used to establish fuel reliability from reactor operation. It is limited to fuel exposed to normal operation and anticipated operational occurrences (i.e. events which are anticipated to occur within a reactor lifetime), and not to fuel that has been exposed to severe accidents. Fuel burnup projections have been limited to the current commercial reactor licensing environment with restrictions on fuel enrichment, oxide coating thickness and rod plenum pressures. The information provided in this analysis will be used in

  3. Initial Cladding Condition

    Energy Technology Data Exchange (ETDEWEB)

    E. Siegmann

    2000-08-22

    The purpose of this analysis is to describe the condition of commercial Zircaloy clad fuel as it is received at the Yucca Mountain Project (YMP) site. Most commercial nuclear fuel is encased in Zircaloy cladding. This analysis is developed to describe cladding degradation from the expected failure modes. This includes reactor operation impacts including incipient failures, potential degradation after reactor operation during spent fuel storage in pool and dry storage and impacts due to transportation. Degradation modes include cladding creep, and delayed hydride cracking during dry storage and transportation. Mechanical stresses from fuel handling and transportation vibrations are also included. This Analysis and Model Report (AMR) does not address any potential damage to assemblies that might occur at the YMP surface facilities. Ranges and uncertainties have been defined. This analysis will be the initial boundary condition for the analysis of cladding degradation inside the repository. In accordance with AP-2.13Q, ''Technical Product Development Planning'', a work plan (CRWMS M&O 2000c) was developed, issued, and utilized in the preparation of this document. There are constraints, caveats and limitations to this analysis. This cladding degradation analysis is based on commercial Pressurized Water Reactor (PWR) fuel with Zircaloy cladding but is applicable to Boiling Water Reactor (BWR) fuel. Reactor operating experience for both PWRs and BWRs is used to establish fuel reliability from reactor operation. It is limited to fuel exposed to normal operation and anticipated operational occurrences (i.e. events which are anticipated to occur within a reactor lifetime), and not to fuel that has been exposed to severe accidents. Fuel burnup projections have been limited to the current commercial reactor licensing environment with restrictions on fuel enrichment, oxide coating thickness and rod plenum pressures. The information provided in this analysis

  4. C-tank transfers: Transuranic sludge removal from the C-1, C-2, and W-23 waste storage tanks at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Two fluidic pulse jet mixing systems were used to successfully mobilize remote-handled transuranic sludge for retrieval from three 50,000-gal horizontal waste storage tanks at Oak Ridge National Laboratory (ORNL). The results of this operation indicate that the pulse jet system should be considered for mixing and bulk retrieval of sludges in other vertical and horizontal waste tanks at ORNL and at other U.S. Department of Energy sites

  5. C-tank transfers: Transuranic sludge removal from the C-1, C-2, and W-23 waste storage tanks at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Dahl, T.L.; Lay, A.C.; Taylor, S.A.; Moore, J.W.

    1999-05-01

    Two fluidic pulse jet mixing systems were used to successfully mobilize remote-handled transuranic sludge for retrieval from three 50,000-gal horizontal waste storage tanks at Oak Ridge National Laboratory (ORNL). The results of this operation indicate that the pulse jet system should be considered for mixing and bulk retrieval of sludges in other vertical and horizontal waste tanks at ORNL and at other U.S. Department of Energy sites.

  6. Composting of waste paint sludge containing melamine resin as affected by nutrients and gypsum addition and microbial inoculation

    International Nuclear Information System (INIS)

    Melamine formaldehyde resins have hard and durable properties and are found in many products, including automobile paints. These resins contain high concentrations of nitrogen and, if properly composted, can yield valuable products. We evaluated the effects of starter compost, nutrients, gypsum and microbial inoculation on composting of paint sludge containing melamine resin. A bench-scale composting experiment was conducted at 55 °C for 91 days and then at 30 °C for an additional 56 days. After 91 days, the composts were inoculated with a mixed population of melamine-degrading microorganisms. Melamine resin degradation after the entire 147 days of composting varied between 73 and 95% for the treatments with inoculation of microorganisms compared to 55–74% for the treatments without inoculation. Degradation was also enhanced by nutrients and gypsum additions. Our results infer that large scale composting of melamine resins in paint sludge is possible. - Highlights: ► Melamine resin in waste paint sludges could be efficiently composted at bench scale. ► Melamine resin degradation after 147 days of composting was 73–95% complete. ► Nutrients, gypsum and melamine-degrading microorganisms increased composting rate. ► Melamine degradation products first increased and then decreased in the compost. ► Final compost was enriched in nitrogen and other essential plant nutrients. - Melamine resin in waste paint sludges was efficiently composted at bench scale, with finished composts having low levels of heavy metals and enriched in plant nutrients.

  7. Presence of helminth eggs in sewage sludge from waste water plants; Presencia de huevos de helmintos en lodos procedentes de la depuracion de aguas

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Muro, J. L.; Garcia Orenes, F.; Nieto Asensio, N.; Bonora, I. B.; Morenilla Martinez, J. J.

    2003-07-01

    Land application of sewage sludge is a usual practice in wide areas of the Comunidad Valencia, due the low organic contents and nutrients of the soils, and the sewage sludge is a suitable material to use os organic amendment of soils. However the use of sewage sludge involves a very detailed characterization of sewage, to avoid sanitary hazards as the presence of helminth eggs and its high resistant to most of the treatment used to stabilize sewage sludge. The aim of this work was determine the parasitic contamination of helminths found in sewage sludge, stabilized by anaerobic digestion, from two waste water plants of Alicante (Alcoy y Benidorm) destined to agricultural land. Also it was studies the evolution of helminth eggs content of a sewage sludge subjected to composting process. (Author) 12 refs.

  8. Hydrochar from sewage sludge and urban wastes as a peat replacement in growing media preparation

    Science.gov (United States)

    Álvarez, Maria Luisa; Méndez, Ana; Paz-Ferreiro, Jorge; Soler-Rovira, Pedro; García-Gil, Juan Carlos; Plaza, César; Gascó, Gabriel

    2016-04-01

    Nowadays, there is an important trend in Europe for peat replacement with biochar in growing media formulation in order to reduce the environmental impact of peat exploitation. Hydrothermal carbonization (HTC) is a thermochemical process of converting organic feedstock into a high carbon rich solid product named hydrochar. It is performed in water mild temperature (180-260°C) under pressure conditions (2-6MPa) for 5-250 min. The reaction pressure is not controlled in the process and is autogenic with the saturation vapour pressure of water corresponding to the reaction temperature. In recent years, the possibility of subjecting organic wastes to HTC has attracted the scientific community attention due to their interesting advantages over other thermal treatments such as pyrolysis, torrefaction or gasification. The aim of the present paper is to study the possible use of two hydrochars produced by Ingelia (Spain) from sewage sludge and urban waste treatment as growing media material in horticulture. For this, thermal, chemical and hydrophysical properties were determined and compared with that of brown commercial peat.

  9. Conversion of Agricultural Wastes to Biogas using as Inoculum Cattle Manure and Activated Sludge

    Directory of Open Access Journals (Sweden)

    Simina Neo

    2012-05-01

    Full Text Available Agricultural wastes represent a large unexploited energy potential that could be converted into biogas by anaerobic digestion. In the present study there has been analysed the way in which agricultural wastes are converted into biogas by using as inoculum cattle manure as compared with activated sludge. To carry out this experiment on small scale there have been designed 5 batch bottles. For the batch process all substrate was put into the bottles at start. The biogas process was initiated after closing the bottles, and the biogas was collected during the process until the biogas production ended. During the 33 days of experiment the batch bottles were held at constant temperature (370C in a water bath. The biomass used in the experiment was wheat straw and corn stalks. Before being used in the experiment the biomass was milled using a kitchen mixer. After that the biomass was subjected to a combination of thermal and chemical pretreatments. The volume of biogas produces was measured every seven days during the experiment period. The biogas production measurements were done by using a BlueSens measuring equipment.

  10. Recent experience with air pollution control on sewage sludge, municipal solid waste and industrial incinerators

    Energy Technology Data Exchange (ETDEWEB)

    Felsvang, K.; Jacobsen, N. [NIRO A/S, Copenhagen (Denmark); Christiansen, O.B. [NIRO Inc., Columbia, MD (United States); Morvan, G. [ABB, Paris (France); Klinke, G. [GEA-Wiegand, Karlsruhe (Germany)

    1996-12-31

    During the last two decades, incineration of sewage sludge, municipal solid waste (MSW) and hazardous waste as a means of volume reduction have grown in importance. Although Europe has been leading the development in the use of incineration, North America today also has a substantial amount of incinerators. As the application of incinerators has increased, concerns have been raised over potential air pollution impacts associated with their use. This has led to the promulgation of emission limits and control requirements for a wide range of pollutants. This paper describes the trends in the emission requirements both in Europe and North America as well as the development of air pollution control technology to cope with the more stringent requirements. The paper describes development of a new process, the High-Performance Spray Dryer Absorber System, which is designed to meet all the new and future emission requirements. Finally the paper deals with mercury removal and results of a 5-year study of mercury revolatilization from dry end product.

  11. Co-digestion of the hydromechanically separated organic fraction of municipal solid waste with sewage sludge.

    Science.gov (United States)

    Borowski, Sebastian

    2015-01-01

    This study investigates the anaerobic digestion of the hydromechanically sorted organic fraction of municipal solid wastes (HS-OFMSW) co-digested with sewage sludge (SS). Eight laboratory-scale experiments were conducted under semi-continuous conditions at 15 and 20 days of solids retention time (SRT). The biogas yield from the waste reached 309 to 315 dm(3)/kgVS and 320 to 361 dm(3)/kgVS under mesophilic and thermophilic conditions, respectively. The addition of SS to HS-OFMSW (1:1 by weight) improved the C/N balance of the mixture, and the production of biogas through anaerobic mesophilic digestion increased to 494 dm(3)/kgVS, which corresponded to 316 dm(3)CH4/kgVS. However, when SS and HS-OFMSW were treated under thermophilic conditions, methanogenesis was inhibited by volatile fatty acids and free ammonia, which concentrations reached 5744 gCH3COOH/m(3) and 1009 gNH3/m(3), respectively. PMID:25262391

  12. Study on Influence to Waste Water Treatment Plant’s Sludge by Low-carbon Catalytic Combustion Furnace of Natural Gas

    Directory of Open Access Journals (Sweden)

    Ren TianQi

    2016-01-01

    Full Text Available There are two parts in this experiment. One of is about the concentration of Variation of exhaust gas while heating sludge of waste water treatment plant. The other one is about introduce the problems of the traditional incineration processes of sludge of waste water treatment as compared between the sludge heated by natural gas catalytic combustion furnace and the tradition’s. We can see that natural gas low-carbon catalytic combustion furnace realize the near-zero emission of contaminates.

  13. Microbial network for waste activated sludge cascade utilization in an integrated system of microbial electrolysis and anaerobic fermentation

    DEFF Research Database (Denmark)

    Liu, Wenzong; He, Zhangwei; Yang, Chunxue;

    2016-01-01

    integrated system of microbial electrolysis cell (MEC) and anaerobic digestion (AD) for waste activated sludge (WAS). Microbial communities in integrated system would build a thorough energetic and metabolic interaction network regarding fermentation communities and electrode respiring communities. The...... Parabacteroides, which showed a delayed contribution to the extracellular electron transport leading to a slow cascade utilization of WAS. Conclusions: Efficient pretreatment could supply more short-chain fatty acids and higher conductivities in the fermentative liquid, which facilitated mass transfer in anodic...

  14. Start-up and HRT Influence in Thermophilic and Mesophilic Anaerobic Digesters Seeded with Waste Activated Sludge

    OpenAIRE

    Benabdallah, El-Hadj T.; Dosta, J.; Mata-Alvarez, J.

    2007-01-01

    Since thermophilic anaerobic digestion represents an efficient alternative to mesophilic anaerobic digestion, multiple studies have been developed to compare their performance and viability. One of the problems related to thermophilic anaerobic digestion is the availability of an adequate seed to start-up the process. The goal of this study is to evaluate the possibility of using waste activated sludge (WAS) as a seed for both mesophilic (35 °C) and thermophilic (55 °C) anaerobic digesters...

  15. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    OpenAIRE

    Yiwen Liu; Qilin Wang; Yaobin Zhang; Bing-Jie Ni

    2015-01-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. Th...

  16. Treatment and use of sewage sludge and liquid agricultural wastes. Review of COST 68/681 programme, 1972-90

    International Nuclear Information System (INIS)

    This report summarizes the activities of the Community concerted action programme (finally termed COST 681) on the treatment and use of sewage sludge, and latterly of liquid agricultural waste, from its inception in the early 1970s to the end of 1990. It was prepared by WRC of the UK on behalf of DG XII of the Commission of the European Communities. (author). refs., Figs., Tabs

  17. Initial demonstration of the vitrification of nuclear waste sludge containing an organic Cs-loaded ion exchange resin

    International Nuclear Information System (INIS)

    When immobilizing into borosilicate glass the radionuclides in the caustic high-level radioactive wastes stored in the USA, the soluble fission product Cs-137 has to be removed from supernates of the wastes. In the current processes zeolites or an organic precipitant will be used to remove the Cs. These solids are then treated further and mixed with the radioactive sludges and vitrified into a borosilicate glass. This paper describes the vitrification of a mixture resulting from using a new process to remove Cs from the caustic supernate. An organic ion exchange resin is used. This resin was then mixed with sludge andfrit and vitrified. Using an organic ion exchange resin rather than zeolite or the organic precipitant has certain advantages. Some of these are discussed in the paper. Results in the paper indicate that a mixture of the resin, sludge and frit can be successfully vitrified in a joule-heated, slurry fed melter. The redox state of the glass is lowered by the presence of the resin in the feed, but the glass is still suitable as a canistered wasteform for radioactive waste glass

  18. Thermal behaviour of chrome shavings and of sludges recovered after digestion of tanned solid wastes with calcium hydroxide

    International Nuclear Information System (INIS)

    The thermal behaviour of chrome shavings and of sludges recovered after digestion of tanned wastes with Ca(OH)2 was studied. Ashes obtained after incineration of wastes at various temperatures were analysed by X-ray diffraction and EDX method. The main crystallized phases present in the ash obtained at 600 deg. C are Cr2O3 and NaCl. The diffractograms revealed an increase in the intensities of the chromium oxide peaks and a very notable decrease of the amount of sodium chloride at 1100 deg. C. EDX analysis revealed a total disappearance of the chlorine peak at this temperature. Scanning electron micrographs show that the waste lost its fibrous aspect when the temperature increases. Formation of aggregates was noted after 550 deg. C. Combustion of organic matters and decarbonation phenomenon are the main stages observed on GTA and DTA curves of sludges. These phenomena are, respectively, exothermic and endothermic. The diffractogram of sludges recorded at 550 deg. C, in the presence of a constant oxygen surplus, revealed the presence of CaCrO4 and CaCO3

  19. Hazardous waste management in pipeline terminal: a multi-pronged approach for safe disposal of tank bottom sludge

    Energy Technology Data Exchange (ETDEWEB)

    Ammanna, John [Indian Oil Corporation Limited (IOCL), Mumbai (India)

    2009-12-19

    Indian Oil Corporation Ltd., Pipeline Division owns and operates the 1850 Km long Salaya-Mathura Crude Oil Pipeline (SMPL) with installed capacity of 21 MMTPA. Almost 25 types of crude [90% imported and 10% indigenous] are received into 13 on-shore tanks at Vadinar (the Mother Station of SMPL) through 2 Nos. SPM's anchored in the Arabian Sea and located on the west coast of India in the Gulf of Kutch. Larger quantities of tank bottom sludge that gets generated in the terminal during tank M and I pose serious environmental hazards, as procedures for handling, treatment and disposal of hazardous waste are not well established. With increasingly stringent Environmental norms being enforced by Statutory / Regulatory Authorities, storage of hazardous solid waste in lagoons and its disposal through designated approved agencies within the specified time frame, becomes extremely difficult. This paper seeks to address this issue by putting forth an innovative approach to hazardous waste management in pipeline terminals having large crude oil tank farms that has been adopted at Indian Oil Corporation's Vadinar terminal of SMPL where a multi-pronged approach for safe disposal of tank bottom sludge has been successfully implemented. The terminal has since become a 'Zero sludge location'. (author)

  20. Experimental and Mathematical Modelling for Methane Biogas Production from Mixing of Real Municipal Solid Waste and Sewage Sludge

    OpenAIRE

    Faiza E. Gharib*; Ahmed Hassoon Ali; , Wisam Ali Hussein

    2014-01-01

    Biogas (methane) production from batch anaerobic digesters containing varying ratio of organic fraction municipal solid waste and sewage sludge, pH, temperature and total solid are studied for a period of 30 days. It was observed that biogas production was optimized when waste and inoculum were mixed in a ratio of 5:1.At temperature, total solid and pH of 35oC, 10 % and of 7.5 respectively. The maximum accumulative methane production is 450 mL/gm V.S. First order model was deve...

  1. A pilot study of anaerobic membrane digesters for concurrent thickening and digestion of waste activated sludge (WAS).

    Science.gov (United States)

    Dagnew, Martha; Parker, Wayne J; Seto, Peter

    2010-01-01

    The increased interest in biomass energy provides incentive for the development of efficient and high throughput digesters such as anaerobic membrane bioreactors (AnMBRs) to stabilize waste activated sludge (WAS). This paper presents the results of a pilot and short term filtration study that was conducted to assess the performance of AnMBRs when treating WAS at a 15 day hydraulic retention time (HRT) and 30 day sludge retention time (SRT) in comparison to two conventional digesters running at 15 (BSR-15) and 30 days (BSR-30) HRT/SRT. At steady state, the AnMBR digester showed a slightly higher volatile solids (VS) destruction of 48% in comparison to 44% and 35.3% for BSR-30 and BSR-15, respectively. The corresponding values of specific methane production were 0.32, 0.28 and 0.21 m(3) CH(4)/kg of VS fed. Stable membrane operation at an average flux of 40+/-3.6 LM(-2 )H(-1) (LMH) was observed when the digester was fed with a polymer-dosed thickened waste activated sludge (TWAS) and digester total suspended solids (TSS) concentrations were less than 15 gL(-1). Above this solids concentration a flux decline to 24.1+/-2.0 LM(-2) H(-1) was observed. Short term filtration tests conducted using sludge fractions of a 9.7 and 17.1 gL(-1) TSS sludge indicated 84 and 70% decline in filtration performance to be associated with the supernatant fraction of the sludge. At a higher sludge concentration, the introduction of unique fouling control strategy to tubular membranes, a relaxed mode of operation (i.e. 5 minutes permeation and 1 minute relaxation by) significantly increased the flux from 23.8+/-1.1 to 37.8+/-2.3 LMH for a neutral membrane and from 25.7+/-1.1 to 44.9+/-2.9 LMH for a negatively charged membrane. The study clearly indicates that it is technically feasible to employ AnMBRs to achieve a substantial reduction in digester volumes. PMID:20351424

  2. Polyhydroxyalkanoates in waste activated sludge enhances anaerobic methane production through improving biochemical methane potential instead of hydrolysis rate

    Science.gov (United States)

    Wang, Qilin; Sun, Jing; Zhang, Chang; Xie, Guo-Jun; Zhou, Xu; Qian, Jin; Yang, Guojing; Zeng, Guangming; Liu, Yiqi; Wang, Dongbo

    2016-01-01

    Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d-1) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery.

  3. X-ray diffraction of the diminution in the concentration of heavy metals from industrial waste water sludge

    International Nuclear Information System (INIS)

    We worked with an apparatus and process patented for Jaime Vite Torres, in the United States of America, for extracting simultaneously toxic and value metals from foundry sands. In this research, we used similar devices to remove toxic metals of waste water sludge. Generation of solid wastes including dangerous in 1992 in Mexico were 450,000 ton/day in accordance with the National Institut of Ecology (INE-SEDESOL 1992). With the apparatus and process of the present work we obtained two important points, whic are: a) the recovery of metals in solution which can be recycled and, b) an important reduction in the toxic of the wastes which one treated can be handled as normal waste with important savings. From among the metals which it is possible to recover one can mention among others: Au, Pt, Ag, Cr, Mn, Co, Pb, Al, Ni and others. (Author)

  4. Scalable Upcycling Silicon from Waste Slicing Sludge for High-performance Lithium-ion Battery Anodes

    International Nuclear Information System (INIS)

    Silicon (Si) has been perceived as a promising next-generation anode material for lithium ion batteries (LIBs) due to its superior theoretical capacity. Despite the natural abundance of this element on Earth, large-scale production of high-purity Si nanomaterials in a green and energy-efficient way is yet to become an industrial reality. Spray-drying methods have been exploited to recover Si particles from low-value sludge produced in the photovoltaic industry, providing a massive and cost-effective Si resource for fabricating anode materials. To address such drawbacks like volume expansion, low electrical and Li+ conductivity and unstable solid electrolyte interphase (SEI) formation, the recycled silicon particles have been downsized into nanoscale and shielded by a highly conductive and protective graphene multilayer through high energy ball milling. Cyclic voltammetry and electrochemical impedance spectroscopy measurements have revealed that the graphene wrapping and size reduction approach have significantly improved the electrochemical performance. It delivers an excellent reversible capacity of 1,138 mA h g−1 and a long cycle life with 73% capacity retention over 150 cycles at a high current of 450 mA g−1. The plentiful waste conversion methodology also provides considerable opportunities for developing additional rechargeable devices, ceramic, powder metallurgy and silane/siloxane products

  5. Enhanced dewatering of waste-activated sludge by composite hydrolysis enzymes.

    Science.gov (United States)

    Wu, Boran; Chai, Xiaoli; Zhao, Youcai

    2016-04-01

    The feasibility of composite hydrolysis enzymes in enhanced dewatering of waste-activated sludge (WAS) was verified in this study. A Pearson correlation analysis was conducted to explore the roles of different extracellular polymeric substance (EPS) fractions on WAS dewaterability. The results indicated that tightly bound EPS (TB-EPS) was released into the liquid phase consistently during enzymatic hydrolysis to form soluble EPS (S-EPS) and loosely bound EPS and that the TB-EPS content was positively correlated with the capillary suction time of WAS. A kinetic analysis was carried out to gain further insights into the kinetic variation in TB-EPS removal. It was found that TB-EPS reduction fit a first-order kinetic model and that mild temperature (25-30 °C) and a slightly acidic condition were favorable for the improvement of enzyme activity. Solid phase extraction combined with UV-Vis spectroscopy analysis was used to characterize the processes of migration and transformation of the hydrophobic (HPO), transphilic and hydrophilic (HPI) fractions in EPS during the enzymatic process. The results revealed that HPO and HPI were mainly composed of PN and PS, respectively, and that the enzymatic hydrolysis could enhance the transformation of HPI from TB-EPS to S-EPS, which was the dominant mechanism of improving WAS dewaterability. PMID:26815556

  6. Pilot-scale anaerobic co-digestion of municipal wastewater sludge with restaurant grease trap waste.

    Science.gov (United States)

    Razaviarani, Vahid; Buchanan, Ian D; Malik, Shahid; Katalambula, Hassan

    2013-07-15

    The maximum feasible loading rate of grease trap waste (GTW) to the municipal wastewater sludge (MWS) was investigated using two 1300 L pilot-scale (1200 L active volume) digesters under mesophilic conditions at a 20 day solids retention time. During the co-digestion, the test reactor received a mixture of GTW and MWS while the control reactor received only MWS. The test digester loading was increased incrementally to a maximum of 280% of the control digester COD loading. The highest feasible GTW loading was determined to be 23% and 58% in terms of its total 1.58 kg VS/(m(3) d) and 3.99 kg COD/(m(3) d) loadings, respectively. This test digester COD loading represented 240% of the control digester COD loading. At this loading, test digester biogas production was 67% greater than that of the control. During the test digester quasi steady state loading period when VS from GTW represented 19% of its total VS loading, the test digester COD and VS removal rates were 2.5 and 1.5 fold those of the control digester, respectively. The test digester biogas production declined markedly when the percentage of VS from GTW in its feed was increased to 30% of its total VS loading. Causes of the reduced biogas production were investigated and attributed to inhibition due to long chain fatty acid accumulation. PMID:23583789

  7. Bioconversion of volatile fatty acids derived from waste activated sludge into lipids by Cryptococcus curvatus.

    Science.gov (United States)

    Liu, Jia; Liu, Jia-Nan; Yuan, Ming; Shen, Zi-Heng; Peng, Kai-Ming; Lu, Li-Jun; Huang, Xiang-Feng

    2016-07-01

    Pure volatile fatty acid (VFA) solution derived from waste activated sludge (WAS) was used to produce microbial lipids as culture medium in this study, which aimed to realize the resource recovery of WAS and provide low-cost feedstock for biodiesel production simultaneously. Cryptococcus curvatus was selected among three oleaginous yeast to produce lipids with VFAs derived from WAS. In batch cultivation, lipid contents increased from 10.2% to 16.8% when carbon to nitrogen ratio increased from about 3.5 to 165 after removal of ammonia nitrogen by struvite precipitation. The lipid content further increased to 39.6% and the biomass increased from 1.56g/L to 4.53g/L after cultivation for five cycles using sequencing batch culture (SBC) strategy. The lipids produced from WAS-derived VFA solution contained nearly 50% of monounsaturated fatty acids, including palmitic acid, heptadecanoic acid, ginkgolic acid, stearic acid, oleic acid, and linoleic acid, which showed the adequacy of biodiesel production. PMID:27038264

  8. Examination of Uranium(VI) Leaching During Ligand Promoted Dissolution of Waste Tank Sludge Surrogates

    International Nuclear Information System (INIS)

    The dissolution of synthetic boehmite (?-AlOOH) by 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) was examined in a series of batch adsorption/dissolution experiments. Additionally, the leaching behavior of 233U(VI) from boehmite was examined as a function of pH and HEDPA concentration. The results are discussed in terms of sludge washing procedures that may be utilized during underground tank waste remediation. In the pH range 4 to 10, complexation of Al(III) by HEDPA significantly enhanced dissolution of boehmite. This phenomenon was especially pronounced in the neutral pH region where the solubility of aluminum, in the absence of complexants, is limited by the formation of sparsely soluble aluminum hydroxides. At pH higher than 10, dissolution of synthetic boehmite was inhibited by HEDPA, likely due to sorption of Al(III):HEDPA complexes. Addition of HEDPA to equilibrated U(VI)-synthetic boehmite suspensions yielded an increase in the aqueous phase uranium concentration. Partitioning of uranium between the solid and aqueous phase is described in terms of U(VI):HEDPA speciation and dissolution of the boehmite solid phase

  9. Basic Data Report -- Defense Waste Processing Facility Sludge Plant, Savannah River Plant 200-S Area

    Energy Technology Data Exchange (ETDEWEB)

    Amerine, D.B.

    1982-09-01

    This Basic Data Report for the Defense Waste Processing Facility (DWPF)--Sludge Plant was prepared to supplement the Technical Data Summary. Jointly, the two reports were intended to form the basis for the design and construction of the DWPF. To the extent that conflicting information may appear, the Basic Data Report takes precedence over the Technical Data Summary. It describes project objectives and design requirements. Pertinent data on the geology, hydrology, and climate of the site are included. Functions and requirements of the major structures are described to provide guidance in the design of the facilities. Revision 9 of the Basic Data Report was prepared to eliminate inconsistencies between the Technical Data Summary, Basic Data Report and Scopes of Work which were used to prepare the September, 1982 updated CAB. Concurrently, pertinent data (material balance, curie balance, etc.) have also been placed in the Basic Data Report. It is intended that these balances be used as a basis for the continuing design of the DWPF even though minor revisions may be made in these balances in future revisions to the Technical Data Summary.

  10. Production of glass-ceramics from sewage sludge and waste glass

    International Nuclear Information System (INIS)

    In the present study for recycling of sewage sludge and waste glass from JSC 'Valmieras stikla skiedra' treatment of them to the dense glass-ceramic composite material using powder technology is estimated. The physical-chemical properties of composite materials were identified – density 2.19 g/cm3, lowest water absorption of 2.5% and lowest porosity of 5% for the samples obtained in the temperature range of sintering 1120 – 1140 °C. Regarding mineralogical composition of glass-ceramics the following crystalline phases were identified by XRD analysis: quartz (SiO2), anorthite (CaAl2Si2O8) and hematite (Fe2O3), which could ensure the high density of materials and improve the mechanical properties of material - compressive strength up to 60.31±5.09 – 52.67±19.18 MPa. The physical-chemical properties of novel materials corresponds to dense glass-ceramics composite which eventually could be used as a building material, e.g. for floor covering, road pavement, exterior tiles etc.

  11. Batch anaerobic co-digestion of waste activated sludge and microalgae (Chlorella sorokiniana) at mesophilic temperature.

    Science.gov (United States)

    Beltrán, Carolina; Jeison, David; Fermoso, Fernando G; Borja, Rafael

    2016-08-23

    The microalgae Chlorella sorokiniana are used as co-substrate for waste activated sludge (WAS) anaerobic digestion. The specific objective of this research was to evaluate the feasibility of improving methane production from anaerobic digestion of WAS in co-digestion with this microalga, based on an optimized mixture percentage. Thus, the anaerobic co-digestion of both substrates aims to overcome the drawbacks of the anaerobic digestion of single WAS, simultaneously improving its management. Different co-digestion mixtures (0% WAS-100% microalgae; 25% WAS-75% microalgae; 50% WAS-50% microalgae; 75% WAS-25% microalgae; 100% WAS-0% microalgae) were studied. The highest methane yield (442 mL CH4/g VS) was obtained for the mixture with 75% WAS and 25% microalgae. This value was 22% and 39% higher than that obtained in the anaerobic digestion of the sole substrates WAS and microalgae, respectively, as well as 16% and 25% higher than those obtained for the co-digestion mixtures with 25% WAS and 75% microalgae and 50% WAS and 50% microalgae, respectively. The kinetic constant of the process increased 42%, 42% and 12%, respectively, for the mixtures with 25%, 50% and 75% of WAS compared to the substrate without WAS. Anaerobic digestion of WAS, together with C. sorokiniana, has been clearly improved by ensuring its viability, suitability and efficiency. PMID:27230742

  12. Efficient production of cellulase in the culture of Acremonium cellulolyticus using untreated waste paper sludge.

    Science.gov (United States)

    Prasetyo, Joni; Zhu, Jing; Kato, Tatsuya; Park, Enoch Y

    2011-01-01

    Cellulase was produced by Acremonium cellulolyticus using untreated waste paper sludge (PS) as the carbon source. The clay present in PS did not show any inhibitory effect on cellulase production but did alter the pH during fermentation. On the flask scale, the maleate buffer concentration and pH were key factors that affected the efficiency of cellulase production from PS cellulose. Optimum cellulase production in a 3-L fermentor of working volume 1.5 L was achieved by controlling the pH value at 6.0 using 2 M NaOH and 2 M maleic acid, and the productivity reached 8.18 FPU/mL. When 40.89 g/L PS cellulose, 2.2 g/L (NH(4) )(2) SO(4) , and 4.4 g/L urea were added to a 48-h culture, the cellulase activity was 9.31 FPU/mL at the flask scale and 10.96 FPU/mL in the 3-L fermentor. These values are ∼80% of those obtained when pure cellulose is used as the carbon source. The method developed here presents a new route for the utilization of PS. PMID:21312360

  13. Feasibility study of green wastes composting with digested and dewatering sludge from municipal wastewater treatment plant in Iran

    Directory of Open Access Journals (Sweden)

    Neamat Jaafarzadeh Haghighi Fard

    2015-09-01

    Full Text Available Background: Composting as a waste management technology is becoming more widespread. The purpose of this study was to assess the feasibility and to find the most effective composting process for the ratio of green waste, digested and dewatered sludge from Chonibieh wastewater treatment plant in the west region of Ahvaz. Methods: The composting time was 23 days and the evaluated parameters in this period of the study were organic carbon, total nitrogen, phosphorus, carbon to nitrogen ratio (C/N, moisture content and pH. The C/N ratio was maintained at 30 with weight:weight ratio of 1:1, 1:2, 1:3 (digested and dewatered sludge to green waste. Results: It was observed that vessel R3 produced higher quality of compost with final total nitrogen (1.28%, final total phosphorus (0.71%, final total organic carbon (TOC (25.78% and C/N (20.65% within the 23 days of composting. While vessel R1 produced higher final total nitrogen and total phosphorus with lower amount of total coliform indicating suitable quality of composting. Therefore, the results showed that the characteristics of dewatered sludge mixed with green waste proportion of green waste significantly influenced the compost quality and process dynamics. The results also showed that the quality of final products in all the conditions was in agreement with Global Organic Textile Standard (GOTS and World Health Organization (WHO guidelines. However, the moisture content ratios were lower than the mentioned guidelines. With regards to microbial quality, all three ratios were in agreement with US Environmental Protection Agency (EPA and Iranian guidelines. Conclusion: It is suggested that the final product of composting can be safely used in farmland and green space.

  14. Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

    International Nuclear Information System (INIS)

    F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events

  15. Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

    Energy Technology Data Exchange (ETDEWEB)

    Aponte, C.I.

    2000-02-17

    F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events.

  16. Characterization of radioactive wastes: TCLP and microwave digestion of inorganic process sludge, pyrochemical salts, and organic resins

    International Nuclear Information System (INIS)

    A modified SW-846 Method 3051 microwave leach procedure for digestion of transuranic (TRU) waste was developed using surrogates for pyrochemical salt and organic resin waste. The modified procedure uses an aqua regia acid matrix and heating profiles that vary depending on the matrix. For these surrogates adequate spike recoveries were obtained for the Resource Conservation and Recovery Act (RCRA) elements Ag, As, Ba, Be, Cd, Cr, Ni, Pb, and Se. TRU inorganic process sludge was analyzed for RCRA metals after Toxicity Characteristic Leaching Procedure (TCLP) extraction and microwave HNO3 acid digestion. The TCLP results show that analyte concentrations and spike recoveries for a 200mL extractor (10 g sample) are within experimental error of those obtained with the 2L extractor (100g sample). Comparison of the TCLP results with those from Method 3051 digestion of the sludge (0.5g samples) suggests that the microwave method has potential as a screening technique for the analysis of mixed waste samples. A significant advantage of the microwave leach procedures is a minimum 10-fold reduction of waste produced

  17. Method of removing arsenic and/or other amphoteric elements from sludge and solid waste materials

    NARCIS (Netherlands)

    Van Breemen. A.N.

    1990-01-01

    Abstract of WO 9006820 (A1) The noxious element arsenic may be removed with high efficiency from iron hydroxide sludge by first subjecting that sludge first to a thermal treatment in the presence of air or oxygen and of an alkaline reagent and next extracting the treated material with water. The

  18. MEASUREMENT AND CALCULATION OF RADIONUCLIDE ACTIVITIES IN SAVANNAH RIVER SITE HIGH LEVEL WASTE SLUDGE FOR ACCEPTANCE OF DEFENSE WASTE PROCESSING FACILITY GLASS IN A FEDERAL REPOSITORY

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C; David Diprete, D; Ned Bibler, N

    2008-12-31

    This paper describes the results of the analyses of High Level Waste (HLW) sludge slurry samples and of the calculations necessary to decay the radionuclides to meet the reporting requirement in the Waste Acceptance Product Specifications (WAPS) [1]. The concentrations of 45 radionuclides were measured. The results of these analyses provide input for radioactive decay calculations used to project the radionuclide inventory at the specified index years, 2015 and 3115. This information is necessary to complete the Production Records at Savannah River Site's Defense Waste Processing Facility (DWPF) so that the final glass product resulting from Macrobatch 5 (MB5) can eventually be submitted to a Federal Repository. Five of the necessary input radionuclides for the decay calculations could not be measured directly due to their low concentrations and/or analytical interferences. These isotopes are Nb-93m, Pd-107, Cd-113m, Cs-135, and Cm-248. Methods for calculating these species from concentrations of appropriate other radionuclides will be discussed. Also the average age of the MB5 HLW had to be calculated from decay of Sr-90 in order to predict the initial concentration of Nb-93m. As a result of the measurements and calculations, thirty-one WAPS reportable radioactive isotopes were identified for MB5. The total activity of MB5 sludge solids will decrease from 1.6E+04 {micro}Ci (1 {micro}Ci = 3.7E+04 Bq) per gram of total solids in 2008 to 2.3E+01 {micro}Ci per gram of total solids in 3115, a decrease of approximately 700 fold. Finally, evidence will be given for the low observed concentrations of the radionuclides Tc-99, I-129, and Sm-151 in the HLW sludges. These radionuclides were reduced in the MB5 sludge slurry to a fraction of their expected production levels due to SRS processing conditions.

  19. Enhanced treatment of waste frying oil in an activated sludge system by addition of crude rhamnolipid solution

    International Nuclear Information System (INIS)

    The presence of high-strength oil and grease (O and G) in wastewater poses serious challenges for environment. Addition of surfactant into the activated sludge bioreactor is feasible in reducing high concentrations of O and G via enhancing its bioavailability. In this paper, an aqueous biosurfactant solution of rhamnolipid as a cell-free culture broth of Pseudomonas aeruginosa zju.um1 was added into a batch of aerobic activated sludge system for treatment of the waste frying oil. This treatment was conducted on both bench and pilot-scales, whereas the removal efficiency of frying oil was determined by analyzing the residue concentration of O and G and chemical oxygen demand (COD). In the presence of varying concentrations of rhamnolipid from 22.5 mg/L to 90 mg/L, aerobic treatment for 30 h was enough to remove over 93% of O and G while this biodegradability was only 10% in the control system with the absence of rhamnolipids. The equivalent biodegradability was similarly obtained on COD under addition of rhamnolipid. Compared with bench studies, a higher treatment efficiency with the presence of rhamnolipids was achieved on a pilot-scale of activated sludge system, in which a short time of 12 h was required for removing approximately 95% of O and G while the control treatment attained a low efficiency of 17%. Finally, foaming and biodegradability of rhamnolipids in activated sludge system were further examined in the whole treatment process. It seems that the addition of rhamnolipid-containing culture broth showed great potential for treatment of oily wastewater by activated sludge.

  20. Effective bio-treatment of fresh leachate from pretreated municipal solid waste in an expanded granular sludge bed bioreactor.

    Science.gov (United States)

    Liu, Jianyong; Zhong, Jiangping; Wang, Yilan; Liu, Qiang; Qian, Guangren; Zhong, Liyun; Guo, Rongzhong; Zhang, Peijun; Xu, Zhi Ping

    2010-03-01

    This research investigated the anaerobic biodegradation of fresh leachate from pretreated municipal solid waste (MSW) in an expanded granular sludge bed (EGSB) bioreactor under mesophilic conditions. The observations showed that this bioreactor, inoculated with anaerobic granular sludge, could be readily activated. The chemical oxygen demand (COD) removal efficiency varied between 88% and 97% under normal operation conditions, and was kept at 94-96% under the proposed optimal conditions. We noted that 60-80% of the produced biogas was methane that was yielded at a rate depending on the organic loading rate (OLR) and the liquid up-flow velocity (Vup). Significantly, 80% of loaded COD or 83% of biodegraded COD was converted to methane under the proposed optimal conditions. These findings indicate that the fresh leachate from pretreated MSW can be efficiently treated in the EGSB bioreactor, and moreover, methane, a renewable energy, can be continuously generated. PMID:19640701

  1. VERIFICATION OF THE DEFENSE WASTE PROCESSING FACILITY PROCESS DIGESTION METHOD FOR THE SLUDGE BATCH 6 QUALIFICATION SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Click, D.; Jones, M.; Edwards, T.

    2010-06-09

    For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) confirms applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples.1 DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem (CC) Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICPAES). In addition to the CC method confirmation, the DWPF lab's mercury (Hg) digestion method was also evaluated for applicability to SB6 (see DWPF procedure 'Mercury System Operating Manual', Manual: SW4-15.204. Section 6.1, Revision 5, Effective date: 12-04-03). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium Peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestion of Sludge Batch 6 (SB6) SRAT Receipt and SB6 SRAT Product samples. For validation of the DWPF lab's Hg method, only SRAT receipt material was used and compared to AR digestion results. The SB6 SRAT Receipt and SB6 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB6 Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 5 (SB5), to form the SB6 Blend composition. In addition to the 16 elements currently measured by the DWPF, this report includes Hg and thorium (Th) data (Th comprising {approx}2.5 - 3 Wt% of the total solids in SRAT Receipt and SRAT Product, respectively) and provides specific details of ICP-AES analysis of Th. Thorium was found to interfere with the U 367.007 nm emission line, and an inter-element correction (IEC) had to be applied to U

  2. Hybrid alkali-hydrodynamic disintegration of waste-activated sludge before two-stage anaerobic digestion process.

    Science.gov (United States)

    Grübel, Klaudiusz; Suschka, Jan

    2015-05-01

    The first step of anaerobic digestion, the hydrolysis, is regarded as the rate-limiting step in the degradation of complex organic compounds, such as waste-activated sludge (WAS). The aim of lab-scale experiments was to pre-hydrolyze the sludge by means of low intensive alkaline sludge conditioning before applying hydrodynamic disintegration, as the pre-treatment procedure. Application of both processes as a hybrid disintegration sludge technology resulted in a higher organic matter release (soluble chemical oxygen demand (SCOD)) to the liquid sludge phase compared with the effects of processes conducted separately. The total SCOD after alkalization at 9 pH (pH in the range of 8.96-9.10, SCOD = 600 mg O2/L) and after hydrodynamic (SCOD = 1450 mg O2/L) disintegration equaled to 2050 mg/L. However, due to the synergistic effect, the obtained SCOD value amounted to 2800 mg/L, which constitutes an additional chemical oxygen demand (COD) dissolution of about 35 %. Similarly, the synergistic effect after alkalization at 10 pH was also obtained. The applied hybrid pre-hydrolysis technology resulted in a disintegration degree of 28-35%. The experiments aimed at selection of the most appropriate procedures in terms of optimal sludge digestion results, including high organic matter degradation (removal) and high biogas production. The analyzed soft hybrid technology influenced the effectiveness of mesophilic/thermophilic anaerobic digestion in a positive way and ensured the sludge minimization. The adopted pre-treatment technology (alkalization + hydrodynamic cavitation) resulted in 22-27% higher biogas production and 13-28% higher biogas yield. After two stages of anaerobic digestion (mesophilic conditions (MAD) + thermophilic anaerobic digestion (TAD)), the highest total solids (TS) reduction amounted to 45.6% and was received for the following sample at 7 days MAD + 17 days TAD. About 7% higher TS reduction was noticed compared with the sample after 9

  3. Verification Of The Defense Waste Processing Facility Process Digestion Method For The Sludge Batch 6 Qualification Sample

    International Nuclear Information System (INIS)

    For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) confirms applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples.1 DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem (CC) Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICPAES). In addition to the CC method confirmation, the DWPF lab's mercury (Hg) digestion method was also evaluated for applicability to SB6 (see DWPF procedure 'Mercury System Operating Manual', Manual: SW4-15.204. Section 6.1, Revision 5, Effective date: 12-04-03). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium Peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestion of Sludge Batch 6 (SB6) SRAT Receipt and SB6 SRAT Product samples. For validation of the DWPF lab's Hg method, only SRAT receipt material was used and compared to AR digestion results. The SB6 SRAT Receipt and SB6 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB6 Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 5 (SB5), to form the SB6 Blend composition. In addition to the 16 elements currently measured by the DWPF, this report includes Hg and thorium (Th) data (Th comprising ∼2.5 - 3 Wt% of the total solids in SRAT Receipt and SRAT Product, respectively) and provides specific details of ICP-AES analysis of Th. Thorium was found to interfere with the U 367.007 nm emission line, and an inter-element correction (IEC) had to be applied to U data, which is also

  4. Presentation of the project Thermal processes with energy recovery for sludge and special or hazardous waste disposal

    International Nuclear Information System (INIS)

    Main results obtained in the framework of the project Thermal processes with energy recovery for sludge and special waste (also hazardous) disposal granted for 2.16 M Euro by the Italian Ministry of Education through Structural Funds are reported. This project is subdivided into the following four main sub projects: combustion of hazardous sludges on a demonstrative plant; combustion of sludges in fluidized bed reactors on pilot and laboratory scale; set up of a flue gas sampling device at high temperature; fluid dynamic modelling of combustion. Original and interesting results were produced mainly connected with the following aspects: combined incineration of sewage and hazardous sludges appeared to be reliable considering that gaseous emissions did not show any deterioration following the addition of chlorinated hydrocarbons to sewage sludge. Gaseous emissions were found to be not conform with the standards only in very few cases generally not linked with critical conditions: polynuclear aromatic hydrocarbons (PAHs) were found to be a reliable parameter for emissions monitoring considering that they are produced in abundance following up set conditions due to a temperature decline or an insufficient oxygen supply; the very stringent limit at the emissions of 0.1 ng/m3 for dioxins and furans (TE) can be respected in the most of the cases but this monitoring is very complex, time consuming and expensive. Sampling and extraction errors might considerably impact the measured value, which is much more dependent on the conditions inside the recovery boiler rather than on the combustion efficiency; metals are enriched onto the fly ashes produced in the tests carried out by rotating drum furnace more than in the tests by fluidized bed furnace; after burning chamber mode of operation did not display a direct influence on the emissions; incineration tests carried out on reduced pilot scale have shown a total absence of fragmentation during volatilisation while particulate

  5. Characterization of and waste acceptance radionuclide to be reported for the 2nd macro-batch of high-level waste sludge being vitrified in the DWPF melter

    International Nuclear Information System (INIS)

    The Defense Waste Processing Facility (DWPF), at the Savannah River Site (SRS), is currently processing the second million gallon batch (Macro-Batch 2) of radioactive sludge slurry into a durable borosilicate glass for permanent geological disposal. To meet the reporting requirements as specified in the Department of Energy's Waste Acceptance Product Specifications (WAPS), for the final glass product, the nonradioactive and radioactive compositions must be provided for a Macro-Batch of material. In order to meet this requirement, sludge slurry samples from Macro-Batch 2 were analyzed in the Shielded Cells Facility of the Savannah River Technology Center (SRTC). This information is used to complete the necessary Production Records at DWPF so that the final glass product, resulting from Macro Batch 2, may be disposed of at a Federal Repository. This paper describes the results obtained from the analyses of the sludge slurry samples taken from Macro-Batch 2 to meet the reporting requirements of the WAPS. Twenty eight elements were identified for the nonradioactive composition and thirty one for the radioactive composition. The reportable radioisotopes range from C-14 to Cm-246

  6. Method of removing arsenic and/or other amphoteric elements from sludge and solid waste materials

    OpenAIRE

    Van Breemen. A.N.

    1990-01-01

    Abstract of WO 9006820 (A1) The noxious element arsenic may be removed with high efficiency from iron hydroxide sludge by first subjecting that sludge first to a thermal treatment in the presence of air or oxygen and of an alkaline reagent and next extracting the treated material with water. The arsenic present in the extract is thereupon adsorbed to an anion exchanger, eluted with an alkaline aqueous liquid and precipitated in salt form from it. The residual sludge is better suitable for re-...

  7. Behaviour of Main Microbiological Parameters And of Enteric Microorganisms During the Composting of Municipal Solid Wastes and Sewage Sludge in A Semi-Industrial Composting Plant

    OpenAIRE

    O. Fourti; Jedidi, N.; Hassen, A.

    2008-01-01

    This study was focused on the microbiological aspects of composting and on the behaviour of main prevalent microbial communities (non-pathogenic and selected pathogenic bacteria) during the composting process of municipal solid wastes and sewage sludge in a semi-industrial composting plant. Results showed that the dehydrogenase activity and Biomass C / Biomass N ratio showed a noticeable increase in the two windrows W1 (100% of municipal solid wastes) and W2 (60% of municipal solid wastes and...

  8. Ethanol production of semi-simultaneous saccharification and fermentation from mixture of cotton gin waste and recycled paper sludge

    OpenAIRE

    Shen, Jiacheng; Agblevor, Foster A.

    2010-01-01

    Ethanol production from the steam-exploded mixture of 75% cotton gin waste and 25% recycled paper sludge in various conditions was investigated by semi-simultaneous saccharification and fermentation (SSSF) consisting of a pre-hydrolysis and a simultaneous saccharification and fermentation (SSF). Four cases were studied: 24-h pre-hydrolysis + 48-h SSF (SSSF 24), 12-h pre-hydrolysis + 60-h SSF (SSSF 12), 72-h SSF, and 48-h hydrolysis + 24-h fermentation (SHF). The ethanol concentration, yield, ...

  9. Sustainable polysaccharide-based biomaterial recovered from waste aerobic granular sludge as a surface coating material

    NARCIS (Netherlands)

    Lin, Y.M.; Nierop, K.G.J.; Girbal-Neuhauser, E.; Adriaanse, M.; Van Loosdrecht, M.C.M.

    2015-01-01

    To evaluate the possibility of utilizing polysaccharide-based biomaterial recovered from aerobic granular sludge as a coating material, the morphology, molecular weight distribution and chemical composition of the recovered biomaterial were investigated by atomic force microscopy, size exclusion chr

  10. Batch system for study of Cr(VI) Bio sorption by dried waste activated sludge

    International Nuclear Information System (INIS)

    Activated sludge from wastewater treatment systems contains both bacteria and protozoa. The cell wall of bacteria essentially consists of various compounds, such as carboxyl, acidic polysaccharides,lipids, amino acids and other components. (Author)

  11. The chemistry of sludge washing and caustic leaching processes for selected Hanford tank wastes

    International Nuclear Information System (INIS)

    A broad-based study on washing and caustic leaching of Hanford tank sludges was performed in FY 1995 to gain a better understanding of the basic chemical processes that underlie this process. This approach involved testing of the baseline sludge washing and caustic leaching method on several Hanford tank sludges, and characterization of the solids both before and after testing by electron microscopy, X-ray diffraction, and X-ray absorption spectroscopy. A thermodynamically based model was employed to help understand the factors involved in individual specie distribution in the various stages of the sludge washing and caustic leaching treatment. The behavior of the important chemical and radiochemical components throughout the testing is summarized and reviewed in this report

  12. Hazardous sludge wastes of petrochemical industries in the developing countries[Held jointly with the 4. Canadian organic residuals and biosolids managment conference

    Energy Technology Data Exchange (ETDEWEB)

    Ghaheri, M. [Abadan Petrochemical Company, Tehran (Iran, Islamic Republic of); Ghaheri, S. [Azad Univ., Tehran (Iran, Islamic Republic of)

    2007-07-01

    Surface waters and agricultural fields are becoming more and more polluted as a result of waste sludges from wastewater treatment plants such as polyvinyl chloride (PVC) and organo-chlor compounds. In developing countries, environmental development is not parallel to industrial development and most industrial wastewater treatment plants in these countries are producing very harmful sludges. This paper discussed the management of hazardous wastes in Iran and the use of harmful chemical compounds that are being produced the country. The progress that has been made on hazardous waste management practices was also discussed with reference to waste management methods. It was noted that there are no comprehensive hazardous waste treatment and disposal facilities in Iran although many larger scale industries have installed their individual waste treatment facilities to treat hazardous wastes. It was concluded that the responsibility for proper and safe disposal of toxic and hazardous wastes requires the cooperation of government, industry and the general public in developing countries. In addition, it was recommended that the following facilities should be considered and/or supplied by the government due to the low public awareness and lack of public interest: land treatment facilities such as sludge farms; off-site recovery facilities; off-site treatment facilities such as plasma-energy incinerators requiring a high budget; off-site storage facilities including the premises of transport contractors; and, secure landfills designated for the disposal of scheduled wastes.

  13. Effect of short-time aerobic digestion on bioflocculation of extracellular polymeric substances from waste activated sludge.

    Science.gov (United States)

    Zhang, Zhiqiang; Zhang, Jiao; Zhao, Jianfu; Xia, Siqing

    2015-02-01

    The effect of short-time aerobic digestion on bioflocculation of extracellular polymeric substances (EPSs) from waste activated sludge (WAS) was investigated. Bioflocculation of the EPS was found to be enhanced by 2∼6 h of WAS aerobic digestion under the conditions of natural sludge pH (about 7), high sludge concentration by gravity thickening, and dissolved oxygen of about 2 mg/L. With the same EPS extraction method, the total suspended solid content reduction of 0.20 and 0.36 g/L and the volatile suspended solid content reduction of 0.19 and 0.26 g/L were found for the WAS samples before and after aerobic digestion of 4 h. It indicates that more EPS is produced by short-time aerobic digestion of WAS. The scanning electron microscopy images of the WAS samples before and after aerobic digestion of 4 h showed that more EPS appeared on the surface of zoogloea by aerobic digestion, which reconfirmed that WAS aerobic digestion induced abundant formation of EPS. By WAS aerobic digestion, the flocculating rate of the EPS showed about 31 % growth, almost consistent with the growth of its yield (about 34 %). The EPSs obtained before and after the aerobic digestion presented nearly the same components, structures, and Fourier transform infrared spectra. These results revealed that short-time aerobic digestion of WAS enhanced the flocculation of the EPS by promoting its production. PMID:23771440

  14. EFFECTIVENESS OF USING DILUTE OXALIC ACID TO DISSOLVEHIGH LEVEL WASTE IRON BASED SLUDGE SIMULANT

    Energy Technology Data Exchange (ETDEWEB)

    Ketusky, E

    2008-07-11

    At the Savannah River Site (SRS), near Aiken South Carolina, there is a crucial need to remove residual quantities of highly radioactive iron-based sludge from large select underground storage tanks (e.g., 19,000 liters of sludge per tank), in order to support tank closure. The use of oxalic acid is planned to dissolve the residual sludge, hence, helping in the removal. Based on rigorous testing, primarily using 4 and 8 wt% oxalic acid solutions, it was concluded that the more concentrated the acid, the greater the amount of residual sludge that would be dissolved; hence, a baseline technology on using 8 wt% oxalic acid was developed. In stark contrast to the baseline technology, reports from other industries suggest that the dissolution will most effectively occur at 1 wt% oxalic acid (i.e., maintaining the pH near 2). The driver for using less oxalic acid is that less (i.e., moles) would decrease the severity of the downstream impacts (i.e., required oxalate solids removal efforts). To determine the initial feasibility of using 1 wt% acid to dissolve > 90% of the sludge solids, about 19,000 liters of representative sludge was modeled using about 530,000 liters of 0 to 8 wt% oxalic acid solutions. With the chemical thermodynamic equilibrium based software results showing that 1 wt% oxalic acid could theoretically work, simulant dissolution testing was initiated. For the dissolution testing, existing simulant was obtained, and an approximate 20 liter test rig was built. Multiple batch dissolutions of both wet and air-dried simulant were performed. Overall, the testing showed that dilute oxalic acid dissolved a greater fraction of the stimulant and resulted in a significantly larger acid effectiveness (i.e., grams of sludge dissolved/mole of acid) than the baseline technology. With the potential effectiveness confirmed via simulant testing, additional testing, including radioactive sludge testing, is planned.

  15. Chronic Response of Waste Activated Sludge Fermentation to Titanium Dioxide Nanoparticles☆

    Institute of Scientific and Technical Information of China (English)

    Yinguang Chen; Hui Mu; Xiong Zheng⁎

    2014-01-01

    Due to the large-scale production and wide applications, many nanoparticles (NPs) enter wastewater treatment plants and accumulate in activated sludge. It is reported that titanium dioxide (TiO2) NPs show severe damage to many model microbes. However, it is stil unknown whether the long-term (e.g., 100 d) presence of TiO2 NPs would affect the performance of sludge fermentation. In this study, long-term exposure experiments (105 d) were conducted to investigate the potential risk of TiO2 NPs to sludge fermentation system. It is found that the presence of environmental y relevant [6 mg·(g TSS)−1] and higher [150 mg·(g TSS)−1] concentrations of TiO2 NPs does not affect methane production from sludge fermentation. The analysis of fluorescence in situ hybridiza-tion indicates that these concentrations of TiO2 NPs present marginal influences on abundances of bacteria and methanogenic archaea in sludge fermentation system. The viability of sludge microorganisms and activities of key enzymes related to methane production such as protease, acetate kinase, and coenzyme F420 are unchanged by the long-term presence of 6 and 150 mg·(g TSS)−1 of TiO2 NPs. Further investigations reveal that the insolu-bility of NPs and the protection role of sludge extracellular polymeric substances are the main reasons for the marginal influence of TiO2 NPs on sludge fermentation.

  16. "Study of the Biological Treatment of Industrial Waste Water by the Activated Sludge Unit"

    OpenAIRE

    MK Sharifi-Yazdi; C.Azimi; MB Khalili

    2001-01-01

    The activated sludge process simply involves bringing together wastewater and a mixed culture of microorganisms under aerobic conditions. The system usually includes a secondary treatment given to the settled sewage, and requires an environment in which active microorganisms are maintained in intimate contact with wastewater in the presence of sufficient oxygen. In this study, the treatment of industrial effluents, by using laboratory activated sludge unit was investigated. The reduction of t...

  17. INTEGRATED WASTE WATER TREATMENT ACCOMPANIED BY MINIMAL GENERATION OF EXCESSIVE ACTIVATED SLUDGE OR SEDIMENT

    Directory of Open Access Journals (Sweden)

    Makisha Nikolay Alekseevich

    2012-12-01

    ments held. A combination of aerobic and anaerobic processes helps provide the proper quality of integrated biological treatment. Chambers of the aeration reactor are also equipped with the polymer feed of various compositions. Sludge treatment that is also strongly needed was performed by means of aerobic stabilization accompanied by ejecting aeration. The experiment findings demonstrate its substantial effect in terms of both components, including sewage and sludge treatment.

  18. Selective hydrolysis of wastewater sludge. Part 1. Model calculations and cost benefit analysis for Esbjerg West waste water treatment plant, Denmark

    Energy Technology Data Exchange (ETDEWEB)

    OEstergaard, N. (Eurotec West A/S (DK)); Thomsen, Anne Belinda; Thygesen, Anders; Bangsoe Nielsen, H. (Risoe National Laboratory, DTU (DK)); Rasmussen, Soeren (SamRas (DK))

    2007-09-15

    The project 'Selective hydrolysis of wastewater sludge' investigates the possibilities of utilizing selective hydrolysis of sludge at waste water treatment plants to increase the production of biogas based power and heat, and at the same time reduce power consumption for handling and treatment of nitrogen and sludge as well as for disposal of the sludge. The selective hydrolysis system is based on the fact that an anaerobic digestion before a hydrolysis treatment increases the hydrolysis efficiency, as the production of volatile organic components, which might inhibit the hydrolysis efficiency, are not produced to the same extent as may be the case for a hydrolysis made on un-digested material. Furthermore it is possible to separate ammonia from the sludge without using chemicals; it has, however, proven difficult to treat wastewater sludge, as the sludge seems to be difficult to treat in the laboratory using simple equipment. Esbjerg Wastewater Treatment Plant West, Denmark, is used as model plant for the calculations of the benefits using selective hydrolysis of sludge as if established at the existing sludge digester system. The plant is a traditional build plant based on the activated sludge concept in addition to traditional digester technology. The plant treats combined household and factory wastewater with a considerable amount of the wastewater received from the industries. During the project period Esbjerg Treatment Plant West went through considerable process changes, thus the results presented in this report are based on historical plant characteristics and may be viewed as conservative relative to what actually may be obtainable. (BA)

  19. Actual-Waste Tests of Enhanced Chemical Cleaning for Retrieval of SRS HLW Sludge Tank Heels and Decomposition of Oxalic Acid - 12256

    International Nuclear Information System (INIS)

    Savannah River National Laboratory conducted a series of tests on the Enhanced Chemical Cleaning (ECC) process using actual Savannah River Site waste material from Tanks 5F and 12H. Testing involved sludge dissolution with 2 wt% oxalic acid, the decomposition of the oxalates by ozonolysis (with and without the aid of ultraviolet light), the evaporation of water from the product, and tracking the concentrations of key components throughout the process. During ECC actual waste testing, the process was successful in decomposing oxalate to below the target levels without causing substantial physical or chemical changes in the product sludge. During ECC actual waste testing, the introduction of ozone was successful in decomposing oxalate to below the target levels. This testing did not identify physical or chemical changes in the ECC product sludge that would impact downstream processing. The results from these tests confirm observations made by AREVA NP during larger scale testing with waste simulants. This testing, however, had a decreased utilization of ozone, requiring approximately 5 moles of ozone per mole of oxalate decomposed. Decomposition of oxalates in sludge dissolved in 2 wt% OA to levels near 100 ppm oxalate using ECC process conditions required 8 to 12.5 hours without the aid of UV light and 4.5 to 8 hours with the aid of UV light. The pH and ORP were tracked during decomposition testing. Sludge components were tracked during OA decomposition, showing that most components have the highest soluble levels in the initial dissolved sludge and early decomposition samples and exhibit lower soluble levels as OA decomposition progresses. The Deposition Tank storage conditions that included pH adjustment to approximately 1 M free hydroxide tended to bring the soluble concentrations in the ECC product to nearly the same level for each test regardless of storage time, storage temperature, and contact with other tank sludge material. (authors)

  20. Application of Gamma irradiation in treatment of Waste Activated Sludge to Obtain Class a Biosolids

    Directory of Open Access Journals (Sweden)

    Mohammed I. AL-Ghonaiem

    2010-01-01

    Full Text Available Problem statement: The main objective of the current study was investigation of the possible application of Gamma irradiation for treatment of the activated sludge generated wastewater treatment stations, to achieve the standard requirements in term of pathogens content. Approach: Activated sludge samples were collected from Riyadh wastewater plant and analyzed quantitatively for the presence of important bacterial parameters including fecal coliforms and Salmonella spp. The collected samples were treated with various doses of Gamma irradiation and bacterial count was determined. Results: The results indicated that all tested sludge samples were positive for the presence of fecal coliforms and Salmonella spp, with different counts in different stages of wastewater treatment. The raw sludge showed to have the highest coliforms and Salmonella spp counts of 1.1×108 and 2×103 MPN g-1 dry sludge, respectively. Furthermore, coliforms and Salmonella spp were detected in final resulted sludge with count of 2.5×107 and 6×102 MPN g-1 dry sludge, respectively. It was found that treatment of samples with gamma irradiation was able to reduce the fecal coliforms and Salmonella spp effectively and the reduction efficiency was increased by increasing the irradiation dose. Fecal coliforms and Salmonella counts were reduced to less than 100 MPN g-1 dry sludge by exposing to 1.5 and 0.25 kGy respectively. Furthermore, Gamma radiation dose of 2.0 kGy was able to remove both fecal coliforms and Salomnella spp completely. In addition, D10 values were determined and was found to be 0.25 and 0.24 kGy for fecal coliforms and Salmonella spp., respectively. Conclusion/Recommendations: The results indicating that the resulted activated sludge generated from Riyadh wastewater plant are rich with important pathogens and therefore further treatment procedures are necessary to achieve the required standards, before any land application. Application of

  1. Clad Degradation - FEPs Screening Arguments

    International Nuclear Information System (INIS)

    The purpose of this report is to document the screening of the cladding degradation features, events, and processes (FEPs) for commercial spent nuclear fuel (CSNF). This report also addresses the effect of some FEPs on both the cladding and the CSNF, DSNF, and HLW waste forms where it was considered appropriate to address the effects on both materials together. This report summarizes the work of others to screen clad degradation FEPs in a manner consistent with, and used in, the Total System Performance Assessment-License Application (TSPA-LA). This document was prepared according to ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of LA'' (BSC 2004a [DIRS 167796])

  2. Clad Degradation - FEPs Screening Arguments

    Energy Technology Data Exchange (ETDEWEB)

    E. Siegmann

    2004-03-17

    The purpose of this report is to document the screening of the cladding degradation features, events, and processes (FEPs) for commercial spent nuclear fuel (CSNF). This report also addresses the effect of some FEPs on both the cladding and the CSNF, DSNF, and HLW waste forms where it was considered appropriate to address the effects on both materials together. This report summarizes the work of others to screen clad degradation FEPs in a manner consistent with, and used in, the Total System Performance Assessment-License Application (TSPA-LA). This document was prepared according to ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of LA'' (BSC 2004a [DIRS 167796]).

  3. Activities performed within the program of nuclear safety research on structural and cladding materials for innovative reactor system able to transmute nuclear waste

    International Nuclear Information System (INIS)

    The transmutation of nuclear waste to reduce the burden on a geological repository is a relevant topic within the Program of Nuclear Safety Research of the Research Centre Karlsruhe. Several studies have confirmed that a high efficiency of transmutation of actinides is reached in fast neutron spectrum reactor system. Therefore, an important effort is dedicated to the study of transmutation strategies with different fast reactors and their associated technologies. Moreover, in international contexts as Generation IV International Forum (GIF) and Sustainable Nuclear Energy Technology Platform (SNETP), fast reactors are considered in the frame of sustainable development of nuclear energy and reduction of waste. The systems that are currently under investigation, in the frame of the different fuel cycle scenarios, are liquid metal cooled and gas cooled fast reactors as well as Accelerator Driven Sub-critical Transmutation devices (ADS). These innovative reactor systems, call for structural and clad materials, which are able to perform in a safe manner under the envisaged operational and postulated transient conditions. In this context the European Commission supports the FP7 project GETMAT, with the objective to contribute to the development and selection of reference structure materials for core components and primary systems of fast neutron reactors. Several institutes of the Research Centre Karlsruhe are involved in this project with activities in the area of 9Cr ODS steel development and mechanical characterisation; optimisation and ranking of weld and joining techniques as Electron Beam, TIG and Diffusion Bonding; assessment of materials behaviour in corrosive environment and in neutron and neutron/proton irradiation field; and development of corrosion protection barriers for cladding and primary system components and their characterisation. The objective of this contribution is to describe the context in which the GETMAT activities are embedded in the Program

  4. Microstructural characterization of oil sludge waste containing vitrified ceramic bodies; Caracterizacao microestrutural de corpos ceramicos vitrificados contendo residuo borra de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Souza, G.P.; Holanda, J.N.F. [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacazes, RJ (Brazil). Lab. de Materiais Avancados]. E-mail: parente@uenf.br

    2001-07-01

    In Campos Oil Basin, which is responsible for more than 75% of the national petroleum, it is generated great amount of wastes from deep crude oil extraction related activities. Particularly, the oil sludge waste has been intensely studied by the Advanced Materials Lab from UENF, in order to search for alternatives for the waste's treated form reuse in the local ceramics industry, named encapsulated oil sludge waste. In this work, 0, 5, 10, 15 and 20% wt waste containing ceramic bodies were produced and fired at 950 deg C for 1 h. Water absorption ultimate compressive strength and linear shrinkage were determined, as well as bodies microstructure by SEM. The obtained results revealed strict relationship between ceramic properties and sintered bodies microstructure. (author)

  5. Assessment of nutritional value of single-cell protein from waste-activated sludge as a protein supplement in poultry feed.

    Science.gov (United States)

    Nkhalambayausi-Chirwa, Evans M; Lebitso, Moses T

    2012-12-01

    The amount of protein wasted through sludge in Gauteng, South Africa, amounts to 95 000 metric tonne/yr, with the order of magnitude of the national protein requirement of approximately 145 000 metric tonne/yr. Waste-activated sludge (WAS) from wastewater treatment plants (WWTPs) that treat domestic wastewater contains protein in a ratio of 2:1 against fishmeal. This protein source has not been utilized because of the high content of toxic heavy metals and other potential carcinogenic pollutants in the sludge. In this study, a pretreatment method of modified aqua regia dilute acid wash was used to lower the metal content by approximately 60%. However, this resulted in a 33% loss of amino acids in the acid-washed WAS. A feed substitution test in poultry with different fishmeal-sludge ratios (0%, 25%, 50%, 75%, and 100% WAS as percent substitution of fishmeal) showed no impact of sludge single-cell protein (SCP) on mortality rate. However, sludge substitution in the feed yielded weight gains and cost savings up to 46%. PMID:23342942

  6. Antifoam Degradation Products in Off Gas and Condensate of Sludge Batch 9 Simulant Nitric-Formic Flowsheet Testing for the Defense Waste Processing Facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-14

    Ten chemical processing cell (CPC) experiments were performed using simulant to evaluate Sludge Batch 9 for sludge-only and coupled processing using the nitric-formic flowsheet in the Defense Waste Processing Facility (DWPF). Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) cycles were performed on eight of the ten. The other two were SRAT cycles only. Samples of the condensate, sludge, and off gas were taken to monitor the chemistry of the CPC experiments. The Savannah River National Laboratory (SRNL) has previously shown antifoam decomposes to form flammable organic products, (hexamethyldisiloxane (HMDSO), trimethylsilanol (TMS), and propanal), that are present in the vapor phase and condensate of the CPC vessels. To minimize antifoam degradation product formation, a new antifoam addition strategy was implemented at SRNL and DWPF to add antifoam undiluted.

  7. Efficiency Study of Nickel (II and Cadmium (II Biosorption by Powder of Waste Activated Sludge from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    A.A Ebrahimi

    2011-01-01

    Full Text Available "n "n "nBackground and Objective: Nickel (II and cadmium (II are important in environmental pollutant. Biosorption of heavy metals can be an effective process for the removal and recovery of heavy metal ions from aqueous solutions because of the decrease in sludge problems, economical issues, high efficiency and compatibility with the environment."nMaterials and Methods: power of wasted activated sludge have been contact with nickel (II and cadmium (II solutions in 0.25 and 0.75 milli molar invarious pHs and mixing pace, at 24-26 0C temperature on batch reactor system .After two hours (continuously 5-420 min in kinetic study samples were analyzed with atomic absorption spectrophotometer."nResults:The kinetic study results show that equilibrium adsorption time for nickel (II and cadmium"n(II reached within 2 hr, but the profile curve of cadmium (II biosorption was smoother than nickel (II biosorption. Both metals adsorption followed the Langmuir model and the maximum adsorption capacity (qmax for nickel (II and cadmium (II was 0.195 and 0.37 milli mole per gram respectively. The increase in pH resulted in adsorption increase for both metals. For cadmium (II at 0.25 and 0.75 mMinitial concentration there was no adsorption at pH 2 where as nickel (0.25 mM adsorption was observed at the same pH. The optimum mixing rate for both metals was 200 rpm and this effect was more obviously in greater concentration."nConclusion: Like othe biosorbents ,wasted activated sludge showed greater capacity for cadmium(II biosorption than nickel (II. Cadmium (II in modeling and biosorption characteristics study had more conformity than nickel (II.

  8. Anaerobic Codigestion of Sludge: Addition of Butcher’s Fat Waste as a Cosubstrate for Increasing Biogas Production

    Science.gov (United States)

    Martínez, E. J.; Gil, M. V.; Fernandez, C.; Rosas, J. G.

    2016-01-01

    Fat waste discarded from butcheries was used as a cosubstrate in the anaerobic codigestion of sewage sludge (SS). The process was evaluated under mesophilic and thermophilic conditions. The codigestion was successfully attained despite some inhibitory stages initially present that had their origin in the accumulation of volatile fatty acids (VFA) and adsorption of long-chain fatty acids (LCFA). The addition of a fat waste improved digestion stability and increased biogas yields thanks to the higher organic loading rate (OLR) applied to the reactors. However, thermophilic digestion was characterized by an effluent of poor quality and high VFA content. Results from spectroscopic analysis suggested the adsorption of lipid components onto the anaerobic biomass, thus disturbing the complete degradation of substrate during the treatment. The formation of fatty aggregates in the thermophilic reactor prevented process failure by avoiding the exposure of biomass to the toxic effect of high LCFA concentrations. PMID:27071074

  9. Semi-continuous anaerobic co-digestion of thickened waste activated sludge and fat, oil and grease

    International Nuclear Information System (INIS)

    Highlights: → Co-digestion of thickened waste activated sludge (TWAS) with fat, oil and grease (FOG). → Co-digestion of TWAS and FOG at 64% VS increased biogas production by 137%. → FOG addition ratio at 74% of total VS caused inhibition of the anaerobic digestion process. → Micronutrients addition did not significantly improve the biogas production and digestion stabilization. - Abstract: Co-digestion of thickened waste activated sludge (TWAS) and fat, oil and grease (FOG) was conducted semi-continuously under mesophilic conditions. The results showed that daily methane yield at the steady state was 598 L/kg VSadded when TWAS and FOG (64% of total VS) were co-digested, which was 137% higher than that obtained from digestion of TWAS alone. The biogas composition was stabilized at a CH4 and CO2 content of 66.8% and 29.5%, respectively. Micronutrients added to co-digestion did not improve the biogas production and digestion stabilization. With a higher addition of FOG (74% of total VS), the digester initially failed but was slowly self-recovered; however, the methane yield was only about 50% of a healthy reactor with the same organic loading rate.

  10. Ceramicrete stabilization of radioactive-salt-containing liquid waste and sludge water. Final CRADA report.

    Energy Technology Data Exchange (ETDEWEB)

    Ehst, D.; Nuclear Engineering Division

    2010-08-04

    It was found that the Ceramicrete Specimens incorporated the Streams 1 and 2 sludges with the adjusted loading about 41.6 and 31.6%, respectively, have a high solidity. The visible cracks in the matrix materials and around the anionite AV-17 granules included could not obtain. The granules mentioned above fixed by Ceramicrete matrix very strongly. Consequently, we can conclude that irradiation of Ceramecrete matrix, goes from the high radioactive elements, not result the structural degradation. Based on the chemical analysis of specimens No.462 and No.461 used it was shown that these matrix included the formation elements (P, K, Mg, O), but in the different samples their correlations are different. These ratios of the content of elements included are about {+-} 10%. This information shows a great homogeneity of matrix prepared. In the list of the elements founded, expect the matrix formation elements, we detected also Ca and Si (from the wollastonite - the necessary for Ceramicrete compound); Na, Al, S, O, Cl, Fe, Ni also have been detected in the Specimen No.642 from the waste forms: NaCl, Al(OH){sub 3}, Na{sub 2}SO{sub 4}. Fe(OH){sub 3}, nickel ferrocyanide and Ni(NO{sub 3})2. The unintelligible results also were found from analysis of an AV-17 granules, in which we obtain the great amount of K. The X-ray radiographs of the Ceramicrete specimens with loading 41.4 % of Stream 1 and 31.6% of Stream 2, respectively showed that the realization of the advance technology, created at GEOHKI, leads to formation of excellent ceramic matrix with high amount of radioactive streams up to 40% and more. Really, during the interaction with start compounds MgO and KH{sub 2}PO{sub 4} with the present of H{sub 3}BO{sub 3} and Wollastonite this process run with high speed under the controlled regimes. That fact that the Ceramicrete matrix with 30-40% of Streams 1 and 2 have a crystalline form, not amorphous matter, allows to permit that these matrix should be very stable, reliable

  11. Mesophilic and thermophilic alkaline fermentation of waste activated sludge for hydrogen production: Focusing on homoacetogenesis.

    Science.gov (United States)

    Wan, Jingjing; Jing, Yuhang; Zhang, Shicheng; Angelidaki, Irini; Luo, Gang

    2016-10-01

    The present study compared the mesophilic and thermophilic alkaline fermentation of waste activated sludge (WAS) for hydrogen production with focus on homoacetogenesis, which mediated the consumption of H2 and CO2 for acetate production. Batch experiments showed that hydrogen yield of WAS increased from 19.2 mL H2/gVSS at 37 °C and pH 10-80.1 mL H2/gVSS at 55 °C and pH 10. However, the production of volatile fatty acids (mainly acetate) was higher at 37 °C and pH 10 by comparison with 55 °C and pH 10. Hydrogen consumption due to homoacetogenesis was observed at 37 °C and pH 10 but not 55 °C and pH 10. Higher expression levels of genes relating with homoacetogenesis and lower expression levels of genes relating with hydrogen production were found at 37 °C and pH 10 compared to 55 °C and pH 10. The continuous experiment demonstrated the steady-state hydrogen yield of WAS was comparable to that obtained from batch experiments at 55 °C and pH 10, and homoacetogenesis was still inhibited. However, the steady-state hydrogen yield of WAS (6.5 mL H2/gVSS) was much lower than that (19.2 mL H2/gVSS) obtained from batch experiments at 37 °C and pH 10 due to the gradual enrichment of homoacetogens as demonstrated by qPCR analysis. The high-throughput sequencing analysis of 16S rRNA genes showed that the abundance of genus Clostridium, containing several homoacetogens, was 5 times higher at 37 °C and pH 10 than 55 °C and pH 10. PMID:27420808

  12. Improving the biogas production performance of municipal waste activated sludge via disperser induced microwave disintegration.

    Science.gov (United States)

    Kavitha, S; Rajesh Banu, J; Vinoth Kumar, J; Rajkumar, M

    2016-10-01

    In this study, the influence of disperser induced microwave pretreatment was investigated to analyze the proficiency of floc disruption on subsequent disintegration and biodegradability process. Initially, the flocs in the sludge was disrupted through disperser at a specific energy input of 25.3kJ/kgTS. The upshot of the microwave disintegration presents that the solids reduction and solubilization of floc disrupted (disperser induced microwave pretreated) sludge was found to be 17.33% and 22% relatively greater than that achieved in microwave pretreated (9.3% and 16%) sludge alone. The biodegradability analysis, affords an evaluation of parameter confidence and correlation determination. The eventual biodegradability of microwave pretreated, and floc disrupted sludges were computed to be 0.15(gCOD/gCOD) and 0.28(gCOD/gCOD), respectively. An economic assessment of this study offers a positive net profit of about 104.8USD/ton of sludge in floc disrupted sample. PMID:26897472

  13. Formation of nitrous oxide (N2O) in activated sludge from waste-water treatment plants

    International Nuclear Information System (INIS)

    In activated sludge from wastewater treatment plants nitrous oxide is formed, under reduced levels of oxygen or anoxic conditions. Especially higher nitrite concentration stimulated stronger production of N2O under anoxic conditions. Already when the dissolved O2 falls below 1,8 mg/l, N2O formation sets in. The maximal N2O production is observed at about 0,9 mg/l O2. As dissolved O2 sinks even further (to near zero), the rate of N2O formation falls again, unless other unfavorable environmental conditions stimulate N2O production. Activated sludge from the same treatment plant taken at different times can show quite different N2O production under standard conditions. N2O formation in activated sludge samples taken from different treatment plants ranges from 20 to more than 7000 ml N2O per hour per kg of protein (biomass). These experiments indicate, in addition, that sludges with particularly high N2O formation showed remarkebly lower nitrification rates upon aeration than sludges with lower N2O production. - The floc-forming bacteria, which under anoxic conditions use nitrate in place of oxygen as electron acceptor in an anaerobic respiration and which can contribute to N2O formation, are members of different metabolic groups. (orig.)

  14. Aquatic worm reactor for improved sludge processing and resource recovery

    OpenAIRE

    Hendrickx, T.L.G.

    2009-01-01

    Municipal waste water treatment is mainly achieved by biological processes. These processes produce huge volumes of waste sludge (up 1.5 million m3/year in the Netherlands). Further processing of the waste sludge involves transportation, thickening and incineration. A decrease in the amount of waste sludge would be both environmentally and economically attractive. Aquatic worms can be used to reduce the amount of waste sludge. After predation by the worms, the amount of final sludge is lower....

  15. Biological pretreatment of non-flocculated sludge augments the biogas production in the anaerobic digestion of the pretreated waste activated sludge.

    Science.gov (United States)

    Merrylin, J; Kumar, S Adish; Kaliappan, S; Yeom, Ick-Tae; Banu, J Rajesh

    2013-01-01

    High-efficiency resource recovery from municipal solid waste (MSW) has been a focus of attention. The objective of this research is to develop a bio-pretreatment process for application prior to the anaerobic digestion of MSW to improve methane productivity. Bacillus licheniformis was used for pretreating MSW (non-flocculated with 0.07% citric acid), followed by anaerobic digestion. Laboratory-scale experiments were carried out in semi-continuous bioreactors, with a total volume of 5 L and working volume of 3 L. Among the nine organic loading rates (OLRs) investigated, the OLR of 0.84 kg SS m(-3) reactor day(-1) was found to be the most appropriate for economic operation of the reactor. Pretreatment of MSW prior to anaerobic digestion led to 55% and 64% increase of suspended solids (SS) and volatile solids reduction, respectively, with an improvement of 57% in biogas production. The results indicate that the pretreatment of non-flocculated sludge with Bacillus licheniformis which consumes less energy compared to other pretreatment techniques could be a cost-effective and environmentally sound method for producing methane from MSW. PMID:24350465

  16. Effect of ultrasound, low-temperature thermal and alkali pre-treatments on waste activated sludge rheology, hygienization and methane potential.

    Science.gov (United States)

    Ruiz-Hernando, M; Martín-Díaz, J; Labanda, J; Mata-Alvarez, J; Llorens, J; Lucena, F; Astals, S

    2014-09-15

    Waste activated sludge is slower to biodegrade under anaerobic conditions than is primary sludge due to the glycan strands present in microbial cell walls. The use of pre-treatments may help to disrupt cell membranes and improve waste activated sludge biodegradability. In the present study, the effect of ultrasound, low-temperature thermal and alkali pre-treatments on the rheology, hygienization and biodegradability of waste activated sludge was evaluated. The optimum condition of each pre-treatment was selected based on rheological criteria (reduction of steady state viscosity) and hygienization levels (reduction of Escherichia coli, somatic coliphages and spores of sulfite-reducing clostridia). The three pre-treatments were able to reduce the viscosity of the sludge, and this reduction was greater with increasing treatment intensity. However, only the alkali and thermal conditioning allowed the hygienization of the sludge, whereas the ultrasonication did not exhibit any notorious effect on microbial indicators populations. The selected optimum conditions were as follows: 27,000 kJ/kg TS for the ultrasound, 80 °C during 15 min for the thermal and 157 g NaOH/kg TS for the alkali. Afterward, the specific methane production was evaluated through biomethane potential tests at the specified optimum conditions. The alkali pre-treatment exhibited the greatest methane production increase (34%) followed by the ultrasonication (13%), whereas the thermal pre-treatment presented a methane potential similar to the untreated sludge. Finally, an assessment of the different treatment scenarios was conducted considering the results together with an energy balance, which revealed that the ultrasound and alkali treatments entailed higher costs. PMID:24907480

  17. The cultivation of Rhizobial cells in sewage sludge and waste for the production of biological fertilizer

    International Nuclear Information System (INIS)

    The study on the growth of Rhizobium japonicum THA-7 in carriers: Peat Sludge, Filter press cake from sugar industry and the mixer compone nts of Sludge and Filter press cake. These carriers were sterilized by Gamm a radiation at 55 Kilograys. Then rhizobium suspension which grew to late log phase in Mannitol Yeast Extract broth were transfer to carriers. The initial rhizobial cells were 107 cfu at 50 percent moisture content. The maximum growth (109 cfu) was found after incubation at 30oC for 17 days in all carriers. The rhizobial cells were stored in carriers at 4o- 5oC for 120 days. The amount of cells in all carriers were detected at 108 cfu. Maximum survival rate was in the mixture of sludge and filter press cake at the ratio of 1 : 3. Therefore, It should be used as biological fertilizer better than other carriers

  18. CHEMICALLY BONDED CEMENTS FROM BOILER ASH AND SLUDGE WASTES. PHASE II REPORT, SEPT.1998-JULY 1999.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA,T.YAGER,K.A.BLANKENHORN,D.(KEYSPAN R AND D INITIATIVE)

    1999-08-01

    Based upon the previous Phase I research program aimed at looking for ways of recycling the KeySpan-generated wastes, such as waste water treatment sludge (WWTS) and bottom ash (BA), into the potentially useful cementitious materials called chemically bonded cement (CBC) materials, the emphasis of this Phase II program done at Brookhaven National Laboratory, in a period of September 1998 through July 1999, was directed towards the two major subjects: One was to assess the technical feasibility of WWTS-based CBC material for use as Pb-exchange adsorbent (PEA) which remediates Pb-contaminated soils in the field; and the other was related to the establishment of the optimum-packaging storage system of dry BA-based CBC components that make it a promising matrix material for the steam-cured concrete products containing sand and coarse aggregate. To achieve the goal of the first subject, a small-scale field demonstration test was carried out. Using the PEA material consisting of 30 wt% WWTS, 13 wt% Type I cement and 57 wt% water, the PES slurry was prepared using a rotary shear concrete mixer, and then poured on the Pb-contaminated soil. The PEA-to-soil ratio by weight was a factor of 2.0. The placed PEA slurry was blended with soil using hand mixing tools such as claws and shovels. The wettability of soils with the PEA was very good, thereby facilitating the soil-PEA mix procedures. A very promising result was obtained from this field test; in fact, the mount of Pb leached out from the 25-day-aged PEA-treated soil specimen was only 0.74 mg/l, meeting the requirement for EPA safe regulation of < 5 mg/l. In contrast, a large amount (26.4 mg/l) of Pb was detected from the untreated soil of the same age. Thus, this finding demonstrated that the WWTS-based CBC has a potential for use as PEA material. Regarding the second subject, the dry-packed storage system consisting of 68.7 wt% BA, 13.0 wt% calcium aluminate cement (CAC), 13.0 wt% Type I portland cement and 5.3 wt

  19. Bio-Denitrification of the Nitrate Waste Solution from the Lagoon Sludge in a Batch Fermenter

    International Nuclear Information System (INIS)

    It is a serious task to the decommissioning of the uranium conversion plant that the demolition of the lagoon sludge. The main component of the sludge is ammonium nitrate and that is the very explosive material. Therefore, the bio-denitrification is a attractive process to remove the nitrate. In this work, some process variables was tested such as incubation temperature, nitrate concentration, electron donor, C/N ratio, seeding ratio, and pH with an anaerobic bacteria as Pseudomonas halodenitrificans. The results would be used as basic data to the continuous bio-denitrification process.

  20. Investigation and recovery of unrecovered fuel pellets and cladding tube pieces

    International Nuclear Information System (INIS)

    The total weight of the fuel pellets lost due to break was about 1206 g, and cladding tube pieces were about 217 g. Among these, the pellets of about 527 g and the cladding tube pieces of about 152 g were recovered when broken fuel rods were discovered. It is not desirable to leave these broken pieces as unrecovered in view of safety and the management of nuclear fuel materials. Kansai Electric Power Co., Inc., investigated the position and the amount of these pellets and cladding tube pieces for about a year, and recovered a part of them. The results were written in two reports. The objects of the investigation and recovery, and the method of recovery are explained. The UO2 and zirconium recovered were 58.52 g and 369.58 g, respectively. The solid pellets were recovered from the reactor, fuel assemblies, a spent fuel pit and canals, and the content in sludge was recovered from other installations. The amounts of unrecovered pellets and cladding tube pieces in primary cooling water, coolant filters, sealing water filters, primary cooling pipes, waste resins and fuel assemblies were estimated. The problems concerning the recovery and estimation are pointed out. The results of estimating the amount of uranium in coolant filters and sealing water filters are useful to know the time of the occurrence of accident. (Kako, I.)

  1. Characterization of lorry washing sludge

    OpenAIRE

    Moreno Caballero, Ana Isabel; Font Montesinos, Rafael; Gómez-Rico Núñez de Arenas, María Francisca

    2014-01-01

    The sludge generated by washing lorry refuse and some fractions of municipal solid waste have been studied, to justify that washing sludge presents no danger and can therefore be managed adequately in a landfill, as well as other municipal solid waste fractions. One problem attributed to this type of sludge is its high level of sulfide content, which causes this waste to be considered hazardous. The determination of sulfide content in the studied samples was carried out according to environme...

  2. Microbial community dynamics linked to enhanced substrate availability and biogas production of electrokinetically pre-treated waste activated sludge.

    Science.gov (United States)

    Westerholm, Maria; Crauwels, Sam; Houtmeyers, Sofie; Meerbergen, Ken; Van Geel, Maarten; Lievens, Bart; Appels, Lise

    2016-10-01

    The restricted hydrolytic degradation rate of complex organic matter presents a considerable challenge in anaerobic digestion of waste activated sludge (WAS). Within this context, application of pre-treatment of digester substrate has potential for improved waste management and enhanced biogas production. Anaerobic degradation of untreated or electrokinetically pre-treated WAS was performed in two pilot-scale digesters for 132days. WAS electrokinetically pre-treated with energy input 0.066kJ/kg sludge was used in a first phase of operation and WAS pre-treated with energy input 0.091kJ/kg sludge was used in a second phase (each phase lasted at least three hydraulic retention times). Substrate characteristics before and after pre-treatment and effects on biogas digester performance were comprehensively analysed. To gain insights into influences of altered substrate characteristics on microbial communities, the dynamics within the bacterial and archaeal communities in the two digesters were investigated using 16S rRNA gene sequencing (pyrosequencing) and quantitative PCR (qPCR). Specific primers targeting dominant operation taxonomic units (OTUs) and members of the candidate phylum Cloacimonetes were designed to further evaluate their abundance and dynamics in the digesters. Electrokinetic pre-treatment significantly improved chemical oxygen demand (COD) and carbohydrate solubility and increased biogas production by 10-11% compared with untreated sludge. Compositional similarity of the bacterial community during initial operation and diversification during later operation indicated gradual adaptation of the community to the higher solubility of organic material in the pre-treated substrate. Further analyses revealed positive correlations between gene abundance of dominant OTUs related to Clostridia and Cloacimonetes and increased substrate availability and biogas production. Among the methanogens, the genus Methanosaeta dominated in both digesters. Overall, the

  3. Co-firing of paper sludge with high-calorific industrial wastes in a pilot-scale nozzle-grate incinerator.

    Science.gov (United States)

    Lee, Gyo Woo; Lee, Sung Jun; Jurng, Jongsoo; Hwang, Jungho

    2003-08-01

    Experiments on the co-firing of high-calorific industrial wastes with paper sludge were performed in a pilot-scale industrial waste incinerator with a nozzle-type grate system. The incineration capacity was approximately 160kg/h. The temporal variations in the temperatures and exhaust gas emissions were monitored and used as parameters for determining the desirable incineration conditions. The high CO emissions that were mainly due to the rapid vaporization of combustibles from high-calorific industrial wastes could be alleviated through the co-firing of sludge with the high-calorific industrial wastes. Because of the high nitrogen content in the sludge, the increase in the co-firing rate caused higher NO emissions in the flue gas. If the total calorific value of the feed was lower than 750,000kcal/h, for 25-30% of sludge co-firing, the temperature of gases exiting the secondary combustion chamber might be lower than that required by regulations. PMID:12935759

  4. Hazard Evaluation for Storage of Spent Nuclear Fuel (SNF) Sludge at the Solid Waste Treatment Facility

    International Nuclear Information System (INIS)

    As part of the Spent Nuclear Fuel (SNF) storage basin clean-up project, sludge that has accumulated in the K Basins due to corrosion of damaged irradiated N Reactor will be loaded into containers and placed in interim storage. The Hanford Site Treatment Complex (T Plant) has been identified as the location where the sludge will be stored until final disposition of the material occurs. Long term storage of sludge from the K Basin fuel storage facilities requires identification and analysis of potential accidents involving sludge storage in T Plant. This report is prepared as the initial step in the safety assurance process described in DOE Order 5480.23, Nuclear Safety Analysis Reports and HNF-PRO-704, Hazards and Accident Analysis Process. This report documents the evaluation of potential hazards and off-normal events associated with sludge storage activities. This information will be used in subsequent safety analyses, design, and operations procedure development to ensure safe storage. The hazards evaluation for the storage of SNF sludge in T-Plant used the Hazards and Operability Analysis (HazOp) method. The hazard evaluation identified 42 potential hazardous conditions. No hazardous conditions involving hazardous/toxic chemical concerns were identified. Of the 42 items identified in the HazOp study, eight were determined to have potential for onsite worker consequences. No items with potential offsite consequences were identified in the HazOp study. Hazardous conditions with potential onsite worker or offsite consequences are candidates for quantitative consequence analysis. The hazardous conditions with potential onsite worker consequences were grouped into two event categories, Container failure due to overpressure - internal to T Plant, and Spill of multiple containers. The two event categories will be developed into accident scenarios that will be quantitatively analyzed to determine release consequences. A third category, Container failure due to

  5. Hazard Evaluation for Storage of Spent Nuclear Fuel (SNF) Sludge at the Solid Waste Treatment Facility

    Energy Technology Data Exchange (ETDEWEB)

    SCHULTZ, M.V.

    2000-08-22

    As part of the Spent Nuclear Fuel (SNF) storage basin clean-up project, sludge that has accumulated in the K Basins due to corrosion of damaged irradiated N Reactor will be loaded into containers and placed in interim storage. The Hanford Site Treatment Complex (T Plant) has been identified as the location where the sludge will be stored until final disposition of the material occurs. Long term storage of sludge from the K Basin fuel storage facilities requires identification and analysis of potential accidents involving sludge storage in T Plant. This report is prepared as the initial step in the safety assurance process described in DOE Order 5480.23, Nuclear Safety Analysis Reports and HNF-PRO-704, Hazards and Accident Analysis Process. This report documents the evaluation of potential hazards and off-normal events associated with sludge storage activities. This information will be used in subsequent safety analyses, design, and operations procedure development to ensure safe storage. The hazards evaluation for the storage of SNF sludge in T-Plant used the Hazards and Operability Analysis (HazOp) method. The hazard evaluation identified 42 potential hazardous conditions. No hazardous conditions involving hazardous/toxic chemical concerns were identified. Of the 42 items identified in the HazOp study, eight were determined to have potential for onsite worker consequences. No items with potential offsite consequences were identified in the HazOp study. Hazardous conditions with potential onsite worker or offsite consequences are candidates for quantitative consequence analysis. The hazardous conditions with potential onsite worker consequences were grouped into two event categories, Container failure due to overpressure - internal to T Plant, and Spill of multiple containers. The two event categories will be developed into accident scenarios that will be quantitatively analyzed to determine release consequences. A third category, Container failure due to

  6. VERIFICATION OF THE DEFENSE WASTE PROCESSING FACILITY'S (DWPF) PROCESS DIGESTION METHOD FOR THE SLUDGE BATCH 7A QUALIFICATION SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Click, D.; Edwards, T.; Jones, M.; Wiedenman, B.

    2011-03-14

    For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs confirmation of the applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples. DWPF SRAT samples are typically dissolved using a room temperature HF-HNO{sub 3} acid dissolution (i.e., DWPF Cold Chem Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICP-AES). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestions of Sludge Batch 7a (SB7a) SRAT Receipt and SB7a SRAT Product samples. The SB7a SRAT Receipt and SB7a SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constituates the SB7a Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 6 (SB6), to form the Sb7a Blend composition.

  7. RHEOLOGICAL PROPERTIES OF SAVANNAH RIVER SITE (srs) RADIOACTIVE HIGH LEVEL WASTES AND MELTER FEEDS FOR SLUDGE BATCH 2

    International Nuclear Information System (INIS)

    The Savannah River Site, SRS, is currently pursuing an aggressive program to empty its High Level Waste, HLW, tanks and immobilize its radioactive waste into a durable borosilicate glass in the Defense Waste Processing Facility, DWPF. To create a batch of feed for the DWPF, several tanks of sludge slurry are combined into one of the million gallon, i.e. 3.79E06 liters, feed tanks for DWPF. A batch of feed nominally consists of 500,000 gallons, i.e. 1.89E06 liters. After a batch of feed is prepared, a portion of the batch, 26,500 liters, is transferred to DWPF. This batch is then chemically adjusted in the Chemical Processing Cell, CPC, prior to being fed to the melter to make the final product; canisters filled with glass. During the processing of the third batch, or Sludge Batch 2, of feed through the DWPF CPC, pumping and transfer problems were noted. These problems hindered the processing of the feed through the CPC, and thus impacted canister production in DWPF. In order to investigate the root cause of these problems, data were collected and evaluated for possible trends. One trend noted was the relationship between the pH, solids loading concentration, and temperature of the feed. As any one of these three variables changed, the rheological properties of the feed appeared to change. To determine the dependency of the rheological property, samples were obtained and shipped to Savannah River National Laboratory's, SRNL, Shielded Cells Facility. The samples were processed under two sets of conditions and rheological measurements obtained. The results of the SRNL studies showed that the ending pH of the samples impacted the rheological properties of the sample. Lowering the pH of the sludge slurry resulted in lower plastic viscosity and yield stress values,thus alleviating the processing problems. Increasing the solids loading typically increased both the plastic viscosity and yield stress. There was minimal or no dependency on temperature

  8. Sample preparation of drinking, ground and waste water as well as of sewage sludge, residual materials and wastes

    International Nuclear Information System (INIS)

    The primary objective of the preparation of water and sewage sludge samples consists in reducing the volume of the sample aimed at increasing their activity concentration or specific activity, that means the radionuclide(s) to be determined are to be enriched in the sample in order to reduce the detection limit. As a rule, a simplified preparation procedure may be used, such as evaporation of water samples, drying of sludge samples, because the determination of nuclides by means of gamma spectroscopy is performed parallely and undisturbedly. It is also usual to combine different preparation procedures, e.g. to evaporate a water sample converting it into a measuring preparation in filter geometry for gamma spectroscopy, and further converting it into an yttrium-90 measuring preparation in order to determine strontium-90 via the daughter nuclide. (orig./DG)

  9. Ash and sludge covering of mine waste. Benefits and/or risks using ash and sludge for covering of mine waste; Askor och roetslam som taeckskikt foer gruvavfall. Foerdelar och/eller risker med att anvaenda aska och slam som taeckskikt foer gruvavfall

    Energy Technology Data Exchange (ETDEWEB)

    Baeckstroem, Mattias; Johansson, Inger [Oerebro Univ. (Sweden). Man-Technology-Environment Research Centre

    2004-01-01

    One of the main sources for metal pollution in Sweden is mine waste. One way to decrease the leaching of metals from mine waste areas is covering which decreases the formation of acid drainage. There is a shortage of appropriate materials to use for covering, and excavation of till and clay from the environment might cause damages on the landscape. Previous studies have demonstrated that sludge and ashes are suitable materials for covering of waste deposits. When covering mine waste with ash and sludge various positive effects would arise, since the production of drainage water decreases as well as the pH increases due to the high buffer-capacity of the ash. In Ervalla outside Oerebro an area with mine waste has been covered with ash and sludge. This area gives a unique possibility to study benefits and/or risks with the covering of mine waste with ash and sludge. This report is a summary of the first phase of the project and the focus has been on characterisation of the material that has been used for covering. Also a monitoring program for the area has started. Preliminary findings indicate that that the covering decreases the leaching of some metals whereas the leaching of some metals increases. A decrease in the concentration of iron, nickel, cobalt and lead was observed and an increase was observed for arsenic, barium, chromium and copper.

  10. Geophysical investigation of the 116-B-11 retention basin, 116-B-1 liquid waste disposal trench, and 116-B-13 sludge trench, 100-BC-1 Operable Unit

    International Nuclear Information System (INIS)

    This report summarizes the results of geophysical investigations and data integration conducted for the 116-B-1 liquid waste disposal trench, the 116-B-11 retention basin, and the 116-B-13 sludge trench, which are all located at the 100-BC-1 Operable Unit (Figure 1). The objectives of this investigation include the following: Map the extent of 116-B-1 trench and any anomalous debris/material that may have been buried in it; Locate and accurately map the walls and pipelines associated with the 116-B-11 retention basin; and Locate and map the 116-B-13 sludge trench

  11. Anaerobic co-digestion of biodiesel waste glycerin with municipal wastewater sludge: microbial community structure dynamics and reactor performance.

    Science.gov (United States)

    Razaviarani, Vahid; Buchanan, Ian D

    2015-04-01

    Two 10 L completely mixed reactors operating at 37°C and 20 days SRT were used to evaluate the relationships between reactor performance and microbial community dynamics during anaerobic co-digestion of biodiesel waste glycerin (BWG) with municipal wastewater sludge (MWS). The addition of up to 1.35% (v/v) BWG to reactor feeds yielded increased VS and COD removal together with enhanced the biogas production and methane yield. This represented 50% of the MWS feed COD. Pyrosequencing analysis showed Methanosaeta (acetoclastic) and Methanomicrobium (hydrogenotrophic) to be the methanogenic genera present in greatest diversity during stable reactor operation. Methanosaeta sequences predominated at the lowest BWG loading while those of Methanomicrobium were present in greatest abundance at the higher BWG loadings. Genus Candidatus cloacamonas was present in the greatest number of bacterial sequences at all loadings. Alkalinity, pH, biogas production and methane yield declined and VFA concentrations (especially propionate) increased during the highest BWG loading. PMID:25678409

  12. An investigation of magnox sludge and alumino-ferric floc waste simulate, immobilised by a cementitious matrix

    International Nuclear Information System (INIS)

    Magnox sludge and alumino ferric floc simulates, prepared using non-radioactive tracers were immobilised by a cementitious system. Formulation design aimed at optimising pollutant leaching with permeability and compressive strength as secondary considerations. The behaviour of the products under accelerated weathering conditions was investigated. The study was divided into two parts: Formulation design in Phase I and the systematic testing of the optimum formulations under freeze-thaw, and hydration -dehydration conditions in Phase 2. Analytical method development for leachate analysis continued through both Phases. The Barnwood method of leach testing was used. The immobilised waste had good physical properties (i.e. high strength and low permeability) and a significant improvement was achieved during the course of the work in the leach rates of the tracers, particularly of caesium and strontium. (author)

  13. Effects of additives on the co-pyrolysis of municipal solid waste and paper sludge by using thermogravimetric analysis.

    Science.gov (United States)

    Fang, Shiwen; Yu, Zhaosheng; Lin, Yan; Lin, Yousheng; Fan, Yunlong; Liao, Yanfen; Ma, Xiaoqian

    2016-06-01

    By using thermogravimetric analysis (TGA), the effects of different additives (MgO, Al2O3 and ZnO) on the pyrolysis characteristics and activation energy of municipal solid waste (MSW), paper sludge (PS) and their blends in N2 atmosphere had been investigated in this study. The experiments resulted that these additives were effective in reducing the initial temperature and activation energy. However, not all the additives were beneficial to reduce the residue mass and enhance the index D. For the different ratios of MSW and PS, the same additive even had the different influences. The catalytic effects of additives were not obvious and the pyrolysis became difficult with the increase of the proportion of PS. Based on all the contrast of the pyrolysis characteristics, MgO was the best additive and 70M30P was the best ratio, respectively. PMID:26985626

  14. Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA

    International Nuclear Information System (INIS)

    Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra (226Ra plus 228Ra) concentrations commonly exceed 0.185 Bq L-1) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (-1). Combined Ra exceeded 0.185 Bq L-1 at 1 non-maintained system. Combined Ra was enriched in regeneration brine waste (maximum, 81.2 Bq L-1), but concentrations in septic-tank effluents receiving brine waste were less than in the untreated ground waters. The maximum combined Ra concentration in aquifer sands (40.7 Bq kg-1 dry weight) was less than that in sludge from the septic tanks (range, 84-363 Bq kg-1), indicating Ra accumulation in sludge from effluent. The combined Ra concentration in sludge from the homeowners' septic systems falls within the range reported for sludge samples from publicly owned treatment works within the region

  15. Utilization of Paper Sludge Wastes for Treatment of Wastewater from Food Processing Industries

    OpenAIRE

    Tohru Suzuki; Hideyuki Katsumata; Daizo Imai; Kiyoyuki Egusa; Ahmed H.A. Dabwan; Satoshi Kaneco

    2012-01-01

    The food processing industries usually produced large amount of wastewater containing fine and small particles. It takes long time for complete settlement of the fine and small particles in the wastewater. The coagulation method appears to become one of the useful treatments. New inorganic coagulant named “Agoclean‒P” has been developed from paper sludge ash. The treatment by coagulation and flocculation were carried out for the wastewater from three different food processing industries namel...

  16. Laboratory Scale Study of Activated Sludge Process in Jet Loop Reactor for Waste WaterTreatment

    OpenAIRE

    M. S. Patil; G. A. Usmani

    2014-01-01

    The present study was undertaken to evaluate the feasibility of Activated Sludge Process (ASP) for the treatment of synthetic wastewater and to develop a simple design criteria under local conditions.A laboratory scale Compact jet loop reactor model comprising of an aeration tank and final clarifier was used for this purpose.Settled synthetic wastewater was used as influent to the aeration tank. The Chemical Oxygen Demand (COD) of the influent and effluent was measured to find...

  17. K Basin sludge polychlorinated biphenyl removal technology assessment

    International Nuclear Information System (INIS)

    The two Hanford K Basins are water-filled concrete pools that contain over 2,100 metric tons of N Reactor fuel elements stored in aluminum or stainless steel canisters. During the time the fuel has been stored, approximately 50 m3 of heterogeneous solid material have accumulated in the basins. This material, referred to as sludge, is a mixture of fuel corrosion products, metallic bits of spent fuel and zirconium clad iron and metal corrosion products and silica from migrating sands. Some of the sludges also contain PCBs. The congener group of PCBs was identified as Aroclor 1254. The maximum concentration of sludge PCBS was found to be 140 ppm (as settled wet basis). However, the distribution of the PCBs is non-uniform throughout the sludge (i.e., there are regions of high and low concentrations and places where no PCBs are present). Higher concentrations could be present at various locations. Aroclors 1016/1242, 1221, 1248, 1254, and 1260 were identified and quantified in K West (KW) Canister sludge. In some of these samples, the concentration of 1260 was higher than 1254. The sludge requires pre-treatment to meet tank farm waste acceptance criteria, Among the numerous requirements, the sludge should be retreated so that it does not contain regulated levels of Toxic Substances Control Act (TSCA) compounds. Because of their stable chemistry and relative insolubility in water, PCBs are difficult to treat. They also resist degradation from heat and electrical charges. This stability has resulted in environmental persistence which has prompted the development of a variety of new cleanup processes including supercritical processes, advanced oxidation, dehalogenation and others. Hopefully, most of the new processes are discussed herein. Information on new processes are being received and will be evaluated in a future revision

  18. K Basin sludge polychlorinated biphenyl removal technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ashworth, S.C.

    1998-08-25

    The two Hanford K Basins are water-filled concrete pools that contain over 2,100 metric tons of N Reactor fuel elements stored in aluminum or stainless steel canisters. During the time the fuel has been stored, approximately 50 m3 of heterogeneous solid material have accumulated in the basins. This material, referred to as sludge, is a mixture of fuel corrosion products, metallic bits of spent fuel and zirconium clad iron and metal corrosion products and silica from migrating sands. Some of the sludges also contain PCBs. The congener group of PCBs was identified as Aroclor 1254. The maximum concentration of sludge PCBS was found to be 140 ppm (as settled wet basis). However, the distribution of the PCBs is non-uniform throughout the sludge (i.e., there are regions of high and low concentrations and places where no PCBs are present). Higher concentrations could be present at various locations. Aroclors 1016/1242, 1221, 1248, 1254, and 1260 were identified and quantified in K West (KW) Canister sludge. In some of these samples, the concentration of 1260 was higher than 1254. The sludge requires pre-treatment to meet tank farm waste acceptance criteria, Among the numerous requirements, the sludge should be retreated so that it does not contain regulated levels of Toxic Substances Control Act (TSCA) compounds. Because of their stable chemistry and relative insolubility in water, PCBs are difficult to treat. They also resist degradation from heat and electrical charges. This stability has resulted in environmental persistence which has prompted the development of a variety of new cleanup processes including supercritical processes, advanced oxidation, dehalogenation and others. Hopefully, most of the new processes are discussed herein. Information on new processes are being received and will be evaluated in a future revision.

  19. Achieving waste to energy through sewage sludge gasification using hot slags: syngas production

    Science.gov (United States)

    Sun, Yongqi; Nakano, Jinichiro; Liu, Lili; Wang, Xidong; Zhang, Zuotai

    2015-06-01

    To relieve the environmental issues of sewage sludge (SS) disposal and greenhouse gas (GHG) emission in China, we proposed an integrated method for the first time to simultaneously deal with these two problems. The hot slags below 920 °C could act as a good heat carrier for sludge gasification and the increasing CO2 concentration in CO2/O2 atmospheres enhanced the production of CO and H2 at 400-800 °C. Three stages of syngas release were clearly identified by Gaussian fittings, i.e., volatile release, char transformation and fixed carbon reaction. Additionally, the effect of sulfur retention of slags and the synergy effect of the stabilization of toxic elements in the solid residuals were discovered in this study. Furthermore, a novel prototype of multiple industrial and urban systems was put forward, in which the produced CO + H2 could be utilized for direct reduced iron (DRI) production and the solid residuals of sludge ash and glassy slags would be applied as cementitious materials. For a steel plant with an annual production of crude steel of 10 million tons in China, the total annual energy saving and GHG emission reduction achieved are 3.31*105 tons of standard coal and 1.74*106 tons of CO2, respectively.

  20. Partitioning of Tank Waste Sludge in a 5-cm Centrifugal Contactor Under Caustic-Side Solvent Extraction Conditions

    International Nuclear Information System (INIS)

    A test program has been performed to evaluate the effect of solids on the hydraulic performance of a 5-cm centrifugal contactor under conditions present in the extraction section of the Caustic-Side Solvent Extraction (CSSX) process. In addition to determining if the ability to separate the aqueous and organic phases is affected by the presence of solids in a feed solution, the extent to which solids are accumulated in the contactor was also assessed. The reported task was motivated by the need to determine if removal of cesium from Savannah River Site tank waste can be performed using a contactor-based CSSX process without first removing sludge that is suspended in the feed solution. The ability to pass solids through the CSSX process could facilitate placement of CSSX upstream of a process in which alpha-decaying actinides and strontium are removed from the waste stream by precipitation with monosodium titanate (MST). This relative placement of the CSSX and MST processes is desirable because removal of cesium would greatly reduce the activity level of the feed stream to the MST process, thereby reducing the level of shielding needed and mitigating remote maintenance design features of MST equipment. Both results would significantly reduce the cost of the Salt Processing Project. Test results indicate conclusively that a large fraction of suspended sludge that enters the centrifugal contactor remains inside. It is expected that extended operation would result in continued accumulation of solids and that hydraulic performance would be adversely affected. Results also indicate that a fraction of the solids partitions to the phase boundary and could affect phase separation as contactor operations progress

  1. SEISMIC DESIGN REQUIREMENTS SELECTION METHODOLOGY FOR THE SLUDGE TREATMENT and M-91 SOLID WASTE PROCESSING FACILITIES PROJECTS

    International Nuclear Information System (INIS)

    In complying with direction from the U.S. Department of Energy (DOE), Richland Operations Office (RL) (07-KBC-0055, 'Direction Associated with Implementation of DOE-STD-1189 for the Sludge Treatment Project,' and 08-SED-0063, 'RL Action on the Safety Design Strategy (SDS) for Obtaining Additional Solid Waste Processing Capabilities (M-91 Project) and Use of Draft DOE-STD-I 189-YR'), it has been determined that the seismic design requirements currently in the Project Hanford Management Contract (PHMC) will be modified by DOE-STD-1189, Integration of Safety into the Design Process (March 2007 draft), for these two key PHMC projects. Seismic design requirements for other PHMC facilities and projects will remain unchanged. Considering the current early Critical Decision (CD) phases of both the Sludge Treatment Project (STP) and the Solid Waste Processing Facilities (M-91) Project and a strong intent to avoid potentially costly re-work of both engineering and nuclear safety analyses, this document describes how Fluor Hanford, Inc. (FH) will maintain compliance with the PHMC by considering both the current seismic standards referenced by DOE 0 420.1 B, Facility Safety, and draft DOE-STD-1189 (i.e., ASCE/SEI 43-05, Seismic Design Criteria for Structures, Systems, and Components in Nuclear Facilities, and ANSI ANS 2.26-2004, Categorization of Nuclear Facility Structures, Systems and Components for Seismic Design, as modified by draft DOE-STD-1189) to choose the criteria that will result in the most conservative seismic design categorization and engineering design. Following the process described in this document will result in a conservative seismic design categorization and design products. This approach is expected to resolve discrepancies between the existing and new requirements and reduce the risk that project designs and analyses will require revision when the draft DOE-STD-1189 is finalized

  2. Enhancement of anaerobic digestion efficiency of wastewater sludge and olive waste: Synergistic effect of co-digestion and ultrasonic/microwave sludge pre-treatment.

    Science.gov (United States)

    Alagöz, B Aylin; Yenigün, Orhan; Erdinçler, Ayşen

    2015-12-01

    This study investigates the effect of ultrasonic and microwave pre-treatment on biogas production from the anaerobic co-digestion of olive pomace and wastewater sludges. It was found that co-digestion of wastewater sludge with olive pomace yielded around 0.21 L CH4/g VS added, whereas the maximum methane yields from the mono-digestion of olive pomace and un-pretreated wastewater sludges were 0.18 and 0.16L CH4/g VS added. In the same way, compared to mono-digestion of these substrates, co-digestion increased methane production by 17-31%. The microwave and ultrasonic pre-treatments applied to sludge samples prior to co-digestion process led to further increase in the methane production by 52% and 24%, respectively, compared to co-digestion with un-pretreated wastewater sludge. The highest biogas and methane yields were obtained from the co-digestion of 30 min microwave pre-treated wastewater sludges and olive pomace to be 0.46 L/g VS added and 0.32 L CH4/g VS added, respectively. PMID:26320815

  3. Improvement of anaerobic digestion of waste-activated sludge by using H₂O₂ oxidation, electrolysis, electro-oxidation and thermo-alkaline pretreatments.

    Science.gov (United States)

    Feki, Emna; Khoufi, Sonia; Loukil, Slim; Sayadi, Sami

    2015-10-01

    Disintegration of municipal waste-activated sludge (WAS) is regarded as a prerequisite of the anaerobic digestion process to reduce sludge volume and improve biogas yield. Pretreatment of WAS using thermo-alkaline (TA), H2O2 oxidation, electrolysis and electro-oxidation (EO) processes were investigated and compared in term of COD solubilization and biogas production. For each pretreatment, the influences of different operational variables were studied in detail. At optimum conditions, EO gave the maximum COD solubilization (28 %). The effects of pretreatments under the optimum conditions on anaerobic digestion were experienced with biochemical methane potential assay. Significant increases in biogas yield up to 78 and 40 % were observed respectively in the EO and TA pretreated samples compared to raw sludge. Results clearly revealed that the application of EO is a significant alternative method for the improvement of WAS anaerobic digestion. PMID:25982985

  4. Studies on the Electrochemical Dissolution for the Treatment of 10 g-Scale Zircaloy-4 Cladding Hull Wastes in LiCl-KCl Molten Salts

    Energy Technology Data Exchange (ETDEWEB)

    Lee, You Lee; Lee, Jang Hwa; Jeon, Min Ku; Kang, Kweon Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-12-15

    The electrochemical behaviors of 10 g-scale fresh and oxidized Zircaloy-4 cladding hulls were examined in 500 degree C LiCl-KCl molten salts to confirm the feasibility of the electrorefining process for the treatment of hull wastes. In the results of measuring the potential-current response using a stainless steel basket filled with oxidized Zircaloy-4 hull specimens, the oxidation peak of Zr appears to be at -0.7 to -0.8 V vs. Ag/AgCl, which is similar to that of fresh Zircaloy-4 hulls, while the oxidation current is found to be much smaller than that of fresh Zircaloy-4 hulls. These results are congruent with the outcome of current-time curves at -0.78 V and of measuring the change in the average weight and thickness after the electrochemical dissolution process. Although the oxide layer on the surface affects the uniformity and rate of dissolution by decreasing the conductivity of Zircaloy-4 hulls, electrochemical dissolution is considered to occur owing to the defect of the surface and phase properties of the Zr oxide layer.

  5. The use of ultrasound and {gamma}-irradiation as pre-treatments for the anaerobic digestion of waste activated sludge at mesophilic and thermophilic temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Lafitte-Trouque, S.; Forster, C.F. [The University of Birmingham (United Kingdom). School of Engineering

    2002-09-01

    The effect of ultrasound and {gamma}-irradiation used as pre-treatments for the anaerobic digestion of waste activated sludge at both mesophilic and thermophilic temperatures was examined. Untreated activated sludge was also subjected to anaerobic digestion at these temperatures as a control. The sonication time was 90 s using a Soniprep 150 (MSE Scientific Instruments) which operated at 23 kHz and had been adjusted to give an output of 47 W and the {gamma}-irradiation dose was 500 krad. The digesters were operated in a semi-continuous mode, being fed with fresh sludge every 24 h at hydraulic retention times (HRT) of 8, 10 and 12 days. Over the 24 h period the differences between the digesters, in terms of volatile solids (VS) reductions and biogas production, were not statistically significant for any particular set of conditions. Thermophilic digestion performed better than mesophilic digestion in terms of biogas production, VS reductions (except at HRT of 8 days) and specific methane yields and the optimum retention time was 10 days, at both temperatures. When gas production over the initial eight hours (probably the hydrolytic stage) was examined, it was found that the gas production rates for pre-treated sludges were higher than those for untreated sludges. This was most pronounced at thermophilic temperatures and a HRT of 10 days. Sonication did not affect the numbers of faecal coliforms in the sludge. However, {gamma}-irradiation caused a 3-log reduction and, when coupled with mesophilic digestion, gave a product which contained <100 g{sup -1} TS. Thermophilic anaerobic digestion produced sludges which contained <1 g{sup -1} TS irrespective of any pre-treatment. (author)

  6. Characterization and Leach Testing for REDOX Sludge and S-Saltcake Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Fiskum, Sandra K.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Hubler, Timothy L.; Jagoda, Lynette K.; Jenson, Evan D.; Kozelisky, Anne E.; Lumetta, Gregg J.; MacFarlan, Paul J.; McNamara, Bruce K.; Peterson, Reid A.; Sinkov, Sergey I.; Snow, Lanee A.; Swoboda, Robert G.

    2008-07-10

    This report describes processing and analysis results of boehmite waste type (Group 5) and insoluble high Cr waste type (Group 6). The sample selection, compositing, subdivision, physical and chemical characterization are described. Extensive batch leach testing was conducted to define kinetics and leach factors of selected analytes as functions of NaOH concentration and temperature. Testing supports issue M-12 resolution for the Waste Treatment Plant.

  7. Support to the control system for processing of waste sewage sludge into alternative fuel

    OpenAIRE

    Jarc, Gašper

    2013-01-01

    Constant potable water supply, waste water collecting through sewage systems and its purification in treatment plants have become a civilisation standard in the developed countries. Having purified water and different types of solid waste as a final product, the wastewater purification in municipal and other types of treatment plants is actually an advanced imitation of water self-purification as it occurs in nature. A major part of waste produced by municipal treatment plants represents acti...

  8. Disinfection of sludge and waste-water by irradiation with electrons of low accelerating voltage

    International Nuclear Information System (INIS)

    From the point of view of hygiene, sewage sludge and water accumulating in ever increasing quantities, some of which is used in agriculture, represent a potential threat to the health of man and beast, as well as to the environment. It is known that these chains of infection can be broken up by ionizing radiation. The use of natural ionizing radiation or electron radiation with high accelerating voltage has not been accepted in practice because the radiation cannot be cut off and the investment cost for electron accelerators with an accelerating voltage of more than 1 MV is very high. These disadvantages may be overcome by using an electron accelerator with low accelerating voltage. Complex experiments have shown that it is not necessary to adapt the thickness of sewage sludge or water layer to the range of electrons. The layer to be irradiated may be much thicker if the substrate is revolved during irradiation. The advantages of this method are low accelerating voltage for the electrons and hence less costly radiation shielding, complete absorption of the radiated energy by the substrate, and low investment and operating cost. The sterilizing effect of the process can be explained by the secondary reactions that take place in the water, in addition to the primary reactions, when irradiating with high specific ionizing density. It is known from experiments carried out by Muenzner that water irradiated with electrons of high specific ionization density, when added to bacterial cultures, will destroy them. This is explained by the Weiss radical theory of water, with reaction products such as H2, O2 and H2O2. The success of this process is shown by experiments with Escherichia coli, tap water to which Salmonella senftenberg were added, and by the content of Enterobacteriaceae in various sludges as a function of the irradiation period, as well as by the rate at which various invariable species of strongilide larvae, eggs of Ascaris suum, Fasciola hepatica and oocysts

  9. New process controls in the co-fermentation of organic waste and municipal sewage sludge; Neue Verfahrensfuehrungen bei der Co-Vergaerung von Bioabfaellen und kommunalen Klaerschlaemmen

    Energy Technology Data Exchange (ETDEWEB)

    Schaepers, D.; Schierholt, M.; Buer, T.; Risse, H. [Technische Hochschule Aachen (DE). Inst. fuer Siedlungswasserwirtschaft (ISA)

    1999-07-01

    For the co-fermentation of organic waste and sewage sludge in digester towers at municipal sewage treatment plant, mainly single-stage processes have so far been studied or are in use in part. Within the framework of a project sponsored by the foundation Oswald-Schulze-Stiftung, the use of a two-stage mode of operation (thermophilic/mesophilic) for co-fermenting organic waste and sewage sludge was investigated. By adding organic waste to the digester content, biogas production per reactor volume was more than doubled in comparison with exclusive sewage sludge fermentation. Because of the thermophilic stage for the conditioning of organic waste, specific biogas yield for an organic load of 1.5 kg organic dry residue TR/m{sup 3*}d was slightly enhanced in comparison with single-stage co-fermentation. (orig.) [German] Zur Co-Vergaerung von Bioabfaellen und Klaerschlamm in Faultuermen kommunaler Klaeranlagen werden bislang hauptsaechlich einstufige Verfahren untersucht und teilweise eingesetzt. Im Rahmen eines von der Oswald-Schulze-Stiftung gefoerderten Projektes wurde der Einsatz einer 2-stufigen Betriebsweise (thermophil/mesophil) bei der Co-Vergaerung von Bioabfaellen und Klaerschlamm untersucht. Die Biogasproduktion pro Reaktorvolumen konnte durch die Zugabe von Bioabfall in die Faulbehaelter gegenueber der reinen Klaerschlammfaulung mehr als verdoppelt werden. Durch die thermophile Stufe zur Vorbehandlung der Bioabfaelle konnte die spezifische Biogasausbeute bei einer organischen Raumbelastung von 1,5 kg o TR/m{sup 3*}d gegenueber der 1-stufigen Co-Vergaerung leicht erhoeht werden. (orig.)

  10. Anaerobic co-digestion of wine/fruit-juice production waste with landfill leachate diluted municipal sludge cake under semi-continuous flow operation.

    Science.gov (United States)

    Leiva, M Barrantes; Koupaie, E Hosseini; Eskicioglu, C

    2014-10-01

    Anaerobic co-digestion of four organic waste streams; a thickened waste activated sludge (TWAS) and screen cake (SC) from a fruit-juice/winery wastewater treatment plant along with municipal sludge cake (MC) and landfill leachate (LL) was evaluated. A total of eight semi-continuously-fed single and co-digesters were operated side-by-side at sludge retention times (SRT) of 20 and 10 days. Co-digestion of industrial waste streams (TWAS and SC) with MC and LL resulted in increased operational stability compared to the single digestion of industrial TWAS at the higher organic loading (10 d SRT). Although digester operational temperature had no statistically significant effect on organics removal and biogas production, mesophilic digesters had consistently higher total coliform densities (8838-37,959 most probable number or MPN/g-dry weight) compared to the thermophilic digesters (41-6723 MPN/g-dry weight) at both SRTs. Coliform analysis results also proved that most of the thermophilic digestates could be classified as Class A biosolids according to regulations. Furthermore, addition of industrial TWAS to co-digesters enhanced the dewaterability of the digested streams. A cost-benefit analysis confirmed the benefits and indicated that a full-scale co-digester utilizing all four waste streams can decrease the total capital and operational cost by 22% ($10.52 million). PMID:25081853

  11. Separation of oily sludge and glycerol from biodiesel processing waste by coagulation

    OpenAIRE

    Qiao-guang Xie1,; Wirach Taweepreda; Charongpun Musikavong1*; Chaisri Suksaroj 1*

    2011-01-01

    Raw waste glycerol is a by-product of biodiesel production from transesterification, which is high in salt, and has a highpH value (more than 9.6). The purpose of this research is to reduce the water pollution from waste glycerol by using acoagulation process and discussing the possibility of waste glycerol reuse. The commercial coagulant (2% by weight), whichwas composed by cationic polyamine (PA) 6% and poly-aluminium chloride (PACl) 94% (w/w), was used as coagulant totreat waste glycerol. ...

  12. Pilot-scale anaerobic co-digestion of municipal biomass waste and waste activated sludge in China: Effect of organic loading rate

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xiao, E-mail: liuxiao07@mails.tsinghua.edu.cn [School of Environment, Tsinghua University, Beijing 100084 (China); Wang Wei; Shi Yunchun; Zheng Lei [School of Environment, Tsinghua University, Beijing 100084 (China); Gao Xingbao [Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Qiao Wei [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Zhou Yingjun [Department of Urban and Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540 (Japan)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) was examined on a pilot-scale reactor. Black-Right-Pointing-Pointer System performance and stability under OLR of 1.2, 2.4, 3.6, 4.8, 6.0 and 8.0 kg VS (m{sup 3} d){sup -1} were analyzed. Black-Right-Pointing-Pointer A maximum methane production rate of 2.94 m{sup 3} (m{sup 3} d){sup -1} was achieved at OLR of 8.0 kg VS (m{sup 3} d){sup -1} and HRT of 15d. Black-Right-Pointing-Pointer With the increasing OLRs, pH values, VS removal rate and methane concentration decreased and VFA increased. Black-Right-Pointing-Pointer The changing of biogas production rate can be a practical approach to monitor and control anaerobic digestion system. - Abstract: The effects of organic loading rate on the performance and stability of anaerobic co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) were investigated on a pilot-scale reactor. The results showed that stable operation was achieved with organic loading rates (OLR) of 1.2-8.0 kg volatile solid (VS) (m{sup 3} d){sup -1}, with VS reduction rates of 61.7-69.9%, and volumetric biogas production of 0.89-5.28 m{sup 3} (m{sup 3} d){sup -1}. A maximum methane production rate of 2.94 m{sup 3} (m{sup 3} d){sup -1} was achieved at OLR of 8.0 kg VS (m{sup 3} d){sup -1} and hydraulic retention time of 15 days. With increasing OLRs, the anaerobic reactor showed a decrease in VS removal rate, average pH value and methane concentration, and a increase of volatile fatty acid concentration. By monitoring the biogas production rate (BPR), the anaerobic digestion system has a higher acidification risk under an OLR of 8.0 kg VS (m{sup 3} d){sup -1}. This result remarks the possibility of relating bioreactor performance with BPR in order to better understand and monitor anaerobic digestion process.

  13. Pilot-scale anaerobic co-digestion of municipal biomass waste and waste activated sludge in China: Effect of organic loading rate

    International Nuclear Information System (INIS)

    Highlights: ► Co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) was examined on a pilot-scale reactor. ► System performance and stability under OLR of 1.2, 2.4, 3.6, 4.8, 6.0 and 8.0 kg VS (m3 d)−1 were analyzed. ► A maximum methane production rate of 2.94 m3 (m3 d)−1 was achieved at OLR of 8.0 kg VS (m3 d)−1 and HRT of 15d. ► With the increasing OLRs, pH values, VS removal rate and methane concentration decreased and VFA increased. ► The changing of biogas production rate can be a practical approach to monitor and control anaerobic digestion system. - Abstract: The effects of organic loading rate on the performance and stability of anaerobic co-digestion of municipal biomass waste (MBW) and waste activated sludge (WAS) were investigated on a pilot-scale reactor. The results showed that stable operation was achieved with organic loading rates (OLR) of 1.2–8.0 kg volatile solid (VS) (m3 d)−1, with VS reduction rates of 61.7–69.9%, and volumetric biogas production of 0.89–5.28 m3 (m3 d)−1. A maximum methane production rate of 2.94 m3 (m3 d)−1 was achieved at OLR of 8.0 kg VS (m3 d)−1 and hydraulic retention time of 15 days. With increasing OLRs, the anaerobic reactor showed a decrease in VS removal rate, average pH value and methane concentration, and a increase of volatile fatty acid concentration. By monitoring the biogas production rate (BPR), the anaerobic digestion system has a higher acidification risk under an OLR of 8.0 kg VS (m3 d)−1. This result remarks the possibility of relating bioreactor performance with BPR in order to better understand and monitor anaerobic digestion process.

  14. Analysis of the stability of high-solids anaerobic digestion of agro-industrial waste and sewage sludge.

    Science.gov (United States)

    Aymerich, E; Esteban-Gutiérrez, M; Sancho, L

    2013-09-01

    The pilot-scale high-solids anaerobic digestion (HS-AD) of agro-industrial wastes and sewage sludge was analysed in terms of stability by monitoring the most common parameters used to check the performance of anaerobic digesters, i.e. Volatile Fatty Acids (VFA), ammonia nitrogen, pH, alkalinity and methane production. The results reflected similar evolution for the parameters analysed, except for an experiment that presented an unsuccessful start-up. The rest of the experiments ran successfully, although the threshold values proposed in the literature for the detection of an imbalance in wet processes were exceeded, proving the versatility of HS-AD to treat different wastes. The results evidence the need for understanding the dynamics of a high-solids system so as to detect periods of imbalance and to determine inhibitory levels for different compounds formed during anaerobic decomposition. Moreover, the findings presented here could be useful in developing an experimental basis to construct new control strategies for HS-AD. PMID:23859986

  15. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    Science.gov (United States)

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system.

  16. Biomethane production as an alternative bioenergy source from codigesters treating municipal sludge and organic fraction of municipal solid wastes.

    Science.gov (United States)

    Ersahin, M Evren; Gomec, Cigdem Yangin; Dereli, R Kaan; Arikan, Osman; Ozturk, Izzet

    2011-01-01

    Energy recovery potential of a mesophilic co-digester treating OFMSW and primary sludge at an integrated biomethanization plant was investigated based on feasibility study results. Since landfilling is still the main solid waste disposal method in Turkey, land scarcity will become one of the most important obstacles. Restrictions for biodegradable waste disposal to sanitary landfills in EU Landfill Directive and uncontrolled long-term contamination with gas emissions and leachate necessitate alternative management strategies due to rapid increase in MSW production. Moreover, since energy contribution from renewable resources will be required more in the future with increasing oil prices and dwindling supplies of conventional energy sources, the significance of biogas as a renewable fuel has been increased in the last decade. Results indicated that almost 93% of annual total cost can be recovered if 100% renewable energy subsidy is implemented. Besides, considering the potential revenue when replacing transport fuels, about 26 heavy good vehicles or 549 cars may be powered per year by the biogas produced from the proposed biomethanization plant (PE = 100,000; X(PS) = 61 g TS/PE·day; X(SS-OFMSW) = 50 g TS/PE·day). PMID:21274432

  17. Biomethane Production as an Alternative Bioenergy Source from Codigesters Treating Municipal Sludge and Organic Fraction of Municipal Solid Wastes

    Directory of Open Access Journals (Sweden)

    M. Evren Ersahin

    2011-01-01

    Full Text Available Energy recovery potential of a mesophilic co-digester treating OFMSW and primary sludge at an integrated biomethanization plant was investigated based on feasibility study results. Since landfilling is still the main solid waste disposal method in Turkey, land scarcity will become one of the most important obstacles. Restrictions for biodegradable waste disposal to sanitary landfills in EU Landfill Directive and uncontrolled long-term contamination with gas emissions and leachate necessitate alternative management strategies due to rapid increase in MSW production. Moreover, since energy contribution from renewable resources will be required more in the future with increasing oil prices and dwindling supplies of conventional energy sources, the significance of biogas as a renewable fuel has been increased in the last decade. Results indicated that almost 93% of annual total cost can be recovered if 100% renewable energy subsidy is implemented. Besides, considering the potential revenue when replacing transport fuels, about 26 heavy good vehicles or 549 cars may be powered per year by the biogas produced from the proposed biomethanization plant (PE = 100,000; XPS = 61 g TS/PE⋅day; XSS-OFMSW=50 g TS/PE⋅day.

  18. New mechanistically based model for predicting reduction of biosolids waste by ozonation of return activated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Isazadeh, Siavash; Feng, Min; Urbina Rivas, Luis Enrique; Frigon, Dominic, E-mail: dominic.frigon@mcgill.ca

    2014-04-01

    Highlights: • Biomass inactivation followed an exponential decay with increasing ozone doses. • From pure cultures, inactivation did not result in significant COD solubilization. • Ozone dose inactivation thresholds resulted from floc structure modifications. • Modeling description of biomass inactivation during RAS-ozonation was improved. • Model best describing inactivation resulted in best performance predictions. - Abstract: Two pilot-scale activated sludge reactors were operated for 98 days to provide the necessary data to develop and validate a new mathematical model predicting the reduction of biosolids production by ozonation of the return activated sludge (RAS). Three ozone doses were tested during the study. In addition to the pilot-scale study, laboratory-scale experiments were conducted with mixed liquor suspended solids and with pure cultures to parameterize the biomass inactivation process during exposure to ozone. The experiments revealed that biomass inactivation occurred even at the lowest doses, but that it was not associated with extensive COD solubilization. For validation, the model was used to simulate the temporal dynamics of the pilot-scale operational data. Increasing the description accuracy of the inactivation process improved the precision of the model in predicting the operational data.

  19. New mechanistically based model for predicting reduction of biosolids waste by ozonation of return activated sludge

    International Nuclear Information System (INIS)

    Highlights: • Biomass inactivation followed an exponential decay with increasing ozone doses. • From pure cultures, inactivation did not result in significant COD solubilization. • Ozone dose inactivation thresholds resulted from floc structure modifications. • Modeling description of biomass inactivation during RAS-ozonation was improved. • Model best describing inactivation resulted in best performance predictions. - Abstract: Two pilot-scale activated sludge reactors were operated for 98 days to provide the necessary data to develop and validate a new mathematical model predicting the reduction of biosolids production by ozonation of the return activated sludge (RAS). Three ozone doses were tested during the study. In addition to the pilot-scale study, laboratory-scale experiments were conducted with mixed liquor suspended solids and with pure cultures to parameterize the biomass inactivation process during exposure to ozone. The experiments revealed that biomass inactivation occurred even at the lowest doses, but that it was not associated with extensive COD solubilization. For validation, the model was used to simulate the temporal dynamics of the pilot-scale operational data. Increasing the description accuracy of the inactivation process improved the precision of the model in predicting the operational data

  20. The effect of salinity on waste activated sludge alkaline fermentation and kinetic analysis.

    Science.gov (United States)

    Jin, Baodan; Wang, Shuying; Xing, Liqun; Li, Baikun; Peng, Yongzhen

    2016-05-01

    The effect of salinity on sludge alkaline fermentation at low temperature (20°C) was investigated, and a kinetic analysis was performed. Different doses of sodium chloride (NaCl, 0-25g/L) were added into the fermentation system. The batch-mode results showed that the soluble chemical oxygen demand (SCOD) increased with salinity. The hydrolysate (soluble protein, polysaccharide) and the acidification products (short chain fatty acids (SCFAs), NH4(+)-N, and PO4(3-)-P) increased with salinity initially, but slightly declined respectively at higher level salinity (20g/L or 20-25g/L). However, the hydrolytic acidification performance increased in the presence of salt compared to that without salt. Furthermore, the results of Haldane inhibition kinetics analysis showed that the salt enhanced the hydrolysis rate of particulate organic matter from sludge particulate and the specific utilization of hydrolysate, and decreased the specific utilization of SCFAs. Pearson correlation coefficient analysis indicated that the importance of polysaccharide on the accumulation of SCFAs was reduced with salt addition, but the importance of protein and NH4(+)-N on SCFA accumulation was increased. PMID:27155412

  1. Blending in Nuclear Waste Tanks (Salt Disposition Initiative/Tank 50: Blending and Sludge Disturbance Study)

    International Nuclear Information System (INIS)

    The conclusions of this presentation are: (1) Designed, built, and fabricated the test equipment in 16 work days - (a) Six weeks to completion of initial 38 tests, (b) Total of 120 pilot scale tests, 30 CFD models, and 240 material property tests are complete, or in process. (2) 95% blending can be achieved in less than 12 hours - (a) Estimate from in-process test results, (b) Blending time at full scale will be checked from calculations in process, (c) Three to four days typically required to blend tank contents; (3) Recommendation to use one, non-rotating, pump instead of two for each of three tanks. (Pump cost per tank > 1 million dollars) - (a) Pump design parameters provided to SRR: nozzle velocity, nozzle diameter, nozzle angle from horizontal, and pump orientation with respect to the tank wall; and (4) Sludge disturbance was controlled at pilot scale - (a) Numerous models investigated, (b) Sludge disturbance at full scale will be established using CFD modeling and pilot scale test results.

  2. Sludge technology assessment

    International Nuclear Information System (INIS)

    The retrieval, processing, and generation of final waste forms from radioactive tank waste sludges present some of the most challenging technical problems confronting scientists and engineers responsible for the waste management programs at the various Department of Energy laboratories and production facilities. Currently, the Department of Energy is developing a strategy to retrieve, process, and generate a final waste form for the sludge that meets the acceptance criteria for the final disposition. An integral part of this strategy will be use of separation processes that treat the sludge; the goal is to meet feed criteria for the various processes that will generate the final waste form, such as vitrification or grouting. This document is intended to (1) identify separation technologies which are being considered for sludge treatment at various DOE sites, (2) define the current state of sludge treatment technology, (3) identify what research and development is required, (4) identify current research programs within either DOE or academia developing sludge treatment technology, and (5) identify commercial separation technologies which may be applicable. Due to the limited scope of this document, technical evaluations regarding the need for a particular separations technology, the current state of development, or the research required for implementation, are not provided

  3. Maximising biogas in anaerobic digestion by using engine waste heat for thermal hydrolysis pre-treatment of sludge.

    Science.gov (United States)

    Pickworth, B; Adams, J; Panter, K; Solheim, O E

    2006-01-01

    Dublin's Ringsend WWTP was designed to serve a population of approximately 1.2 million p.e. with a sludge production of 37,000 dry tonnes per year after upgrading to full secondary treatment. Several technical solutions were put forward as part of a design, build, finance and operate (DBFO) competition, with the chosen solution being a proposal by Black and Veatch for a combination of sequencing batch reactor (SBR) technology and anaerobic digestion with Cambi thermal hydrolysis pre-treatment (THP). The THP plant was built by Cambi and handed over to B&V in 2002. The plant is now operated by Celtic Anglian Water. In September 2004 a test was carried out on the mass and energy balance of the plant following 2 years of operation and is detailed in this paper. The process enables digestion at very high dry solids feed and low hydraulic retention time. The plant was built with three digesters of 4250 m3 each and is fed with hydrolysed sludge at 11% DS. There are four no. 1 MW Jenbacher engines operating mainly on biogas. Each pair of engines is fitted with a waste heat boiler with a capacity of one tonne steam per hour. These boilers have sufficient capacity to provide 80% of the steam required for the THP, which in turn provides all the heat for the subsequent digestion in the form of hydrolysed feed. There are two main biogas boilers for top up steam and other uses of the biogas including thermal oxidation of concentrated odours. PMID:17087375

  4. Biosorption of chromium, copper and zinc by wine-processing waste sludge: Single and multi-component system study

    International Nuclear Information System (INIS)

    Wine-processing waste sludge (WPWS) has been shown to have powerful potential for sorption of some heavy metals (i.e., chromium, lead and nickel) in single-component aqueous solutions. But although most industrial wastewater contains two or more toxic metals, there are few sorption studies on multicomponent metals by WPWS. This study has two goals: (i) conduct competitive adsorption using Cr, Cu and Zn as sorbates and examine their interaction in binary or ternary systems; and (ii) determine the effects of temperature on the kinetic sorption reaction. The sludge tested contained a high amount of organic matter (38%) and had a high cation exchange capacity (CEC, 255 cmolc kg-1). Infrared analysis reveals that carboxyl is the main functional group in this WPWS. The 13C NMR determination indicates alkyl-C and carboxyl-C are major organic functional groups. At steady state, there are about 40.4% (Cr), 35.0% (Cu) and 21.9% (Zn) sorbed in the initial 6.12 mM of single-component solutions. Only pseudo-second-order sorption kinetic model successfully describes the kinetics of sorption for all experimental metals. The rate constants, k2, of Cr, Cu and Zn in single-component solutions are 0.016, 0.030 and 0.154 g mg-1 min-1, respectively. The sorption of metals by WPWS in this competitive system shows the trend: Cr > Cu > Zn. Ions of charge, hydrated radius and electronic configuration are main factors affecting sorption capacity. The least sorption for Zn in this competitive system can be attributed to its full orbital and largest hydrated radius. Though the effect of temperature on Zn sorption is insignificant, high temperature favors the other metallic sorptions, in particular for Cr. However, the Cr sorption is lower than Cu at 10 deg. C. The Cr sorption by WPWS can be higher than that of Cu at 30 deg. and 50 deg. C.

  5. Filtration and Leach Testing for REDOX Sludge and S-Saltcake Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Shimskey, Rick W.; Billing, Justin M.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Geeting, John GH; Hallen, Richard T.; Jenson, Evan D.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Snow, Lanee A.; Swoboda, Robert G.

    2009-02-20

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan.( ) The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Under test plan TP-RPP-WTP-467, eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. Under this test plan, a waste-testing program was implemented that included: • Homogenizing the archive samples by group as defined in the test plan • Characterizing the homogenized sample groups • Performing parametric leaching testing on each group for compounds of interest • Performing bench-top filtration/leaching tests in the hot cell for each group to simulate filtration and leaching activities if they occurred in the UFP2 vessel of the WTP Pretreatment Facility. This report focuses on filtration/leaching tests performed on two of the eight waste composite samples and follow-on parametric tests to support aluminum leaching results from those tests.

  6. Sewage sludge as additive to reduce the initial fireside corrosion caused by combustion of shredder residues in a waste-fired BFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Jonsson, T.; Pettersson, J.; Johansson, L.G.; Svensson, J.E. [Chalmers Univ. of Technology, Goeteborg (Sweden). Environmental Inorganic Chemistry; Davidsson, K. [SP Technical Research Institute of Sweden, Boraas (Sweden)

    2010-07-01

    Corrosion/deposition field tests have been carried out in a commercial waste-fired BFB boiler using air-cooled probes. The influence of 20% shredder light fraction (SLF), from recovery of metal scrap material, mixed with waste was studied at different material temperatures (280-420 C). In addition, 3% sewage sludge was added to the 20% SLF/waste mixture. The initial deposit and corrosion products were compared to when the normal waste (municipal solid waste and industrial wastes) fuel was used. After 24 hours exposure, the deposits were analyzed as for elemental composition while the corrosion products were characterised by ESEM/EDX and XRD. The results show that combustion of 20% SLF increased the amount of deposition, which in addition contains a larger fraction chlorine. This causes a higher initial corrosion rate. Adding 3% sewage sludge removes the effect of the SLF and deposits and corrosion products were comparable with the ones formed during the reference exposure. The results indicate that the initial fireside corrosion is chlorine induced and no signs of low-melting heavy metals salts were observed in the corrosion products. (orig.)

  7. Effects of sludge recirculation rate and mixing time on performance of a prototype single-stage anaerobic digester for conversion of food wastes to biogas and energy recovery.

    Science.gov (United States)

    Ratanatamskul, Chavalit; Saleart, Tawinan

    2016-04-01

    Food wastes have been recognized as the largest waste stream and accounts for 39.25 % of total municipal solid waste in Thailand. Chulalongkorn University has participated in the program of in situ energy recovery from food wastes under the Ministry of Energy (MOE), Thailand. This research aims to develop a prototype single-stage anaerobic digestion system for biogas production and energy recovery from food wastes inside Chulalongkorn University. Here, the effects of sludge recirculation rate and mixing time were investigated as the main key parameters for the system design and operation. From the results obtained in this study, it was found that the sludge recirculation rate of 100 % and the mixing time of 60 min per day were the most suitable design parameters to achieve high efficiencies in terms of chemical oxygen demand (COD), total solids (TS), and total volatile solid (TVS) removal and also biogas production by this prototype anaerobic digester. The obtained biogas production was found to be 0.71 m(3)/kg COD and the composition of methane was 61.6 %. Moreover, the efficiencies of COD removal were as high as 82.9 % and TVS removal could reach 83.9 % at the optimal condition. Therefore, the developed prototype single-stage anaerobic digester can be highly promising for university canteen application to recover energy from food wastes via biogas production. PMID:25864735

  8. Bio-crude production from secondary pulp/paper-mill sludge and waste newspaper via co-liquefaction in hot-compressed water

    International Nuclear Information System (INIS)

    Co-liquefaction of secondary pulp/paper-mill sludge (solids concentration: 1.6 wt%) and waste newspaper with a total solids concentration of 11.3 wt% was investigated with and without the addition of catalysts in a 75 ml Parr High-Pressure reactor at temperatures of 250-380 oC for 20 min. The yield of heavy oil (HO) without catalyst was between 16.7 and 28.0 wt% within this temperature range, and peaked at 350 oC. The addition of HCO2H, FeS, or KOH at 5 wt% of the total solids (on a dry basis) was found to enhance the HO yield at 300 oC, particularly HCO2H, which increased the yield of HO from 24.9 to 34.4 wt%. More interestingly, synergistic effects between secondary pulp/paper-mill sludge and waste newspaper were observed in the co-liquefaction operations. For example, the HO yield attained was 26.9 wt% at 300 oC in the co-liquefaction of the mixture of 33 wt% sludge and 67 wt% waste newspaper, and was noted to be 9 wt% and 6 wt% higher than the yields obtained from liquefaction of sludge and waste newspaper alone, respectively. The HOs from liquefaction or co-liquefaction at 300 oC for 20 min exhibited significantly higher energy contents (HHV ≥ 30 MJ/kg), almost doubled those (-tilde 16 MJ/kg) of the original feedstocks.

  9. Modelling of thermal and flow processes in a solar waste-water sludge dryer with supplementary heat supply from external sources

    OpenAIRE

    Krzysztof Badyda; Piotr Krawczyk

    2011-01-01

    This article presents the continuation of the research on a model of solar waste-water sludge drying processes. The primary premises for that model were described in [1], [2].This paper presents results of simulation of a drying process powered by solar radiation energy supplemented with external heat delivered to the dried matter through the IR heating lamp installation and floor heating system. The modelling results were used to discuss the impact of individual heat delivery systems on the ...

  10. Methane enhancement through co-digestion of chicken manure and thermo-oxidative cleaved wheat straw with waste activated sludge: A C/N optimization case.

    Science.gov (United States)

    Hassan, Muhammad; Ding, Weimin; Shi, Zhendan; Zhao, Sanqin

    2016-07-01

    The present study emphasized the co-digestion of the thermal-H2O2 pretreated wheat straw (WS) and chicken manure (CM) with the waste activated sludge at four levels of C/N (35:1, 30:1, 25:1 and 20:1). All C/N compositions were found significant (Poptimize the most suitable C/N composition, the process stability of the co-digestion of WS and CM was deeply monitored. PMID:27038262

  11. Clad Degradation- Summary and Abstraction for LA

    International Nuclear Information System (INIS)

    The purpose of this model report is to develop the summary cladding degradation abstraction that will be used in the Total System Performance Assessment for the License Application (TSPA-LA). Most civilian commercial nuclear fuel is encased in Zircaloy cladding. The model addressed in this report is intended to describe the postulated condition of commercial Zircaloy-clad fuel as a function of postclosure time after it is placed in the repository. Earlier total system performance assessments analyzed the waste form as exposed UO2, which was available for degradation at the intrinsic dissolution rate. Water in the waste package quickly became saturated with many of the radionuclides, limiting their release rate. In the total system performance assessments for the Viability Assessment and the Site Recommendation, cladding was analyzed as part of the waste form, limiting the amount of fuel available at any time for degradation. The current model is divided into two stages. The first considers predisposal rod failures (most of which occur during reactor operation and associated activities) and postdisposal mechanical failure (from static loading of rocks) as mechanisms for perforating the cladding. Other fuel failure mechanisms including those caused by handling or transportation have been screened out (excluded) or are treated elsewhere. All stainless-steel-clad fuel, which makes up a small percentage of the overall amount of fuel to be stored, is modeled as failed upon placement in the waste packages. The second stage of the degradation model is the splitting of the cladding from the reaction of water or moist air and UO2. The splitting has been observed to be rapid in comparison to the total system performance assessment time steps and is modeled to be instantaneous. After the cladding splits, the rind buildup inside the cladding widens the split, increasing the diffusion area from the fuel rind to the waste package interior. This model report summarizes the

  12. Utilization of Paper Sludge Wastes for Treatment of Wastewater from Food Processing Industries

    Directory of Open Access Journals (Sweden)

    Tohru Suzuki

    2012-12-01

    Full Text Available The food processing industries usually produced large amount of wastewater containing fine and small particles. It takes long time for complete settlement of the fine and small particles in the wastewater. The coagulation method appears to become one of the useful treatments. New inorganic coagulant named “Agoclean‒P” has been developed from paper sludge ash. The treatment by coagulation and flocculation were carried out for the wastewater from three different food processing industries namely soup, tofu, and natto. “Hi‒Biah‒System”, which is an in‒situ solidification system, was used for the continuous treatment of wastewater. The parameters for the water quality were pH, five‒day biochemical oxygen demand (BOD5, chemical oxygen demand (COD, total suspended solids (TSS, total nitrogen (TN and total phosphorus (TP. These parameters after the treatment became much lower values relative to those obtained before the treatment.

  13. Environmental aspects of using waste waters and sludges in energy forest cultivation

    International Nuclear Information System (INIS)

    From a waste management point of view, energy crops offer the advantage of being non-food crops. Poplar and willow coppice have longer growing seasons and deeper, longer lasting root systems than annual crops, which enables them to have better utilization of mineralised nutrients from waste products. When using waste waters they have the further advantage of a high evapotranspiration. The removal of nutrients from the growth system by harvests is limited, however, and the applied amounts should be regulated accordingly, to avoid leaching of nutrients. Heavy metal contents of waste products for land use are controlled by national regulations. Applications several times higher than is now allowed has had little documented effect on the environment due to the binding of metals to soil particles. The nitrogen content of wood fuels converts mainly to atmospheric nitrogen, but with high temperatures where the combustion is most efficient, there is also some conversion to nitrogen oxides. (author)

  14. Development of high performance cladding

    International Nuclear Information System (INIS)

    The developments of superior next-generation light water reactor are requested on the basis of general view points, such as improvement of safety, economics, reduction of radiation waste and effective utilization of plutonium, until 2030 year in which conventional reactor plants should be renovate. Improvements of stainless steel cladding for conventional high burn-up reactor to more than 100 GWd/t, developments of manufacturing technology for reduced moderation-light water reactor (RMWR) of breeding ratio beyond 1.0 and researches of water-materials interaction on super critical pressure-water cooled reactor are carried out in Japan Atomic Energy Research Institute. Stable austenite stainless steel has been selected for fuel element cladding of advanced boiling water reactor (ABWR). The austenite stain less has the superiority for anti-irradiation properties, corrosion resistance and mechanical strength. A hard spectrum of neutron energy up above 0.1 MeV takes place in core of the reduced moderation-light water reactor, as liquid metal-fast breeding reactor (LMFBR). High performance cladding for the RMWR fuel elements is required to get anti-irradiation properties, corrosion resistance and mechanical strength also. Slow strain rate test (SSRT) of SUS 304 and SUS 316 are carried out for studying stress corrosion cracking (SCC). Irradiation tests in LMFBR are intended to obtain irradiation data for damaged quantity of the cladding materials. (M. Suetake)

  15. Dry anaerobic co-digestion of organic fraction of municipal waste with paperboard mill sludge and gelatin solid waste for enhancement of hydrogen production.

    Science.gov (United States)

    Elsamadony, M; Tawfik, A

    2015-09-01

    The aim of this study is to investigate the bio-H2 production via dry anaerobic co-fermentation of organic fraction of municipal solid waste (OFMSW) with protein and calcium-rich substrates such as gelatin solid waste (GSW) and paperboard mill sludge (PMS). Co-fermentation of OFMSW/GSW/PMS significantly enhanced the H2 production (HP) and H2 yield (HY). The maximum HP of 1082.5±91.4 mL and HY of 144.9±9.8 mL/gVSremoved were achieved at a volumetric ratio of 70% OFMSW:20% GSW:10% PMS. COD, carbohydrate, protein and lipids conversion efficiencies were 60.9±4.4%, 71.4±3.5%, 22.6±2.3% and 20.5±1.8% respectively. Co-fermentation process reduced the particle size distribution which is favorably utilized by hydrogen producing bacteria. The mean particle size diameters for feedstock and the digestate were 939.3 and 115.2μm, respectively with reduction value of 8.15-fold in the mixtures. The volumetric H2 production increased from 4.5±0.3 to 7.2±0.6 L(H2)/L(substrate) at increasing Ca(+2) concentrations from 1.8±0.1 to 6.3±0.5 g/L respectively. PMID:25989091

  16. Enhancement of biogas production from food waste and sewage sludge - Environmental and economic life cycle performance.

    Science.gov (United States)

    Eriksson, Ola; Bisaillon, Mattias; Haraldsson, Mårten; Sundberg, Johan

    2016-06-15

    Management of municipal solid waste is an efficient method to increase resource efficiency, as well as to replace fossil fuels with renewable energy sources due to that (1) waste to a large extent is renewable as it consists of food waste, paper, wood etc. and (2) when energy and materials are recovered from waste treatment, fossil fuels can be substituted. In this paper results from a comprehensive system study of future biological treatment of readily degradable waste in two Swedish regions are presented. Different collection and separation systems for food waste in households have been applied as well as technical improvements of the biogas process as to reduce environmental impact. The results show that central sorting of a mixed fraction into recyclables, combustibles, biowaste and inert is a competitive option compared to source separation. Use of pellets is beneficial compared to direct spreading as fertiliser. Fuel pellets seem to be the most favourable option, which to a large extent depends on the circumstances in the energy system. Separation and utilisation of nitrogen in the wet part of the digestion residue is made possible with a number of technologies which decreases environmental impact drastically, however to a substantial cost in some cases. PMID:27038432

  17. Improved volatile fatty acids anaerobic production from waste activated sludge by pH regulation: Alkaline or neutral pH?

    Science.gov (United States)

    Ma, Huijun; Chen, Xingchun; Liu, He; Liu, Hongbo; Fu, Bo

    2016-02-01

    In this study, the anaerobic fermentation was carried out for volatile fatty acids (VFAs) production at different pH (between 7.0 and 10.0) conditions with untreated sludge and heat-alkaline pretreated waste activated sludge. In the fermentation with untreated sludge, the extent of hydrolysis of organic matters and extent of acidification at alkaline pH are 54.37% and 30.37%, respectively, resulting in the highest VFAs yield at 235.46mg COD/gVS of three pH conditions. In the fermentation with heat-alkaline pretreated sludge, the acidification rate and VFAs yield at neutral pH are 30.98% and 240.14mg COD/gVS, respectively, which are higher than that at other pH conditions. With the glucose or bovine serum albumin as substrate for VFAs production, the neutral pH showed a higher VFAs concentration than the alkaline pH condition. The results of terminal restriction fragment length polymorphism (T-RFLP) analysis indicated that the alkaline pH caused low microbial richness. Based on the results in this study, we demonstrated that the alkaline pH is favor of hydrolysis of organic matter in sludge while neutral pH improved the acidogenesis for the VFAs production from sludge. Our finding is obvious different to the previous research and helpful for the understanding of how heat-alkaline pretreatment and alkaline fermentation influence the VFAs production, and beneficial to the development of VFAs production process. PMID:26652215

  18. High rate mesophilic, thermophilic, and temperature phased anaerobic digestion of waste activated sludge: A pilot scale study

    International Nuclear Information System (INIS)

    Highlights: ► High temperatures were tested in single and two-stage anaerobic digestion of waste activated sludge. ► The increased temperature demonstrated the possibility of improving typical yields of the conventional mesophilic process. ► The temperature phased anaerobic digestion process (65 + 55 °C) showed the best performances with yields of 0.49 m3/kgVSfed. ► Ammonia and phosphate released from solids destruction determined the precipitation of struvite in the reactor. - Abstract: The paper reports the findings of a two-year pilot scale experimental trial for the mesophilic (35 °C), thermophilic (55 °C) and temperature phased (65 + 55 °C) anaerobic digestion of waste activated sludge. During the mesophilic and thermophilic runs, the reactor operated at an organic loading rate of 2.2 kgVS/m3d and a hydraulic retention time of 20 days. In the temperature phased run, the first reactor operated at an organic loading rate of 15 kgVS/m3d and a hydraulic retention time of 2 days while the second reactor operated at an organic loading rate of 2.2 kgVS/m3d and a hydraulic retention time of 18 days (20 days for the whole temperature phased system). The performance of the reactor improved with increases in temperature. The COD removal increased from 35% in mesophilic conditions, to 45% in thermophilic conditions, and 55% in the two stage temperature phased system. As a consequence, the specific biogas production increased from 0.33 to 0.45 and to 0.49 m3/kgVSfed at 35, 55, and 65 + 55 °C, respectively. The extreme thermophilic reactor working at 65 °C showed a high hydrolytic capability and a specific yield of 0.33 gCOD (soluble) per gVSfed. The effluent of the extreme thermophilic reactor showed an average concentration of soluble COD and volatile fatty acids of 20 and 9 g/l, respectively. Acetic and propionic acids were the main compounds found in the acids mixture. Because of the improved digestion efficiency, organic nitrogen and phosphorus were

  19. Fractionation and business potential from sludge - Pafrak

    Energy Technology Data Exchange (ETDEWEB)

    Kylloenen, H.; Groenroos, A.; Pirkonen, P. (VTT Tecchnical Research Centre of Finland, Jyvaeskylae (Finland)), Email: hanna.kyllonen@vtt.fi; Maekinen, L.; Aemmaelae, A.; Niinimaeki, J. (Univ. of Oulu (Finland)), Email: liisa.makinen@oulu.fi

    2010-10-15

    Wastewater sludges contain valuable components which can be recycled and converted to secondary raw material. High water content of sludge can hinder the further processing. Dry solids content of waste activated sludge after dewatering can be as low as 12-20% and even lower for tertiary sludge. This research aimed with better knowledge of sludge and fractionation to generate potential business ideas, which could lead to new sludge based products and services in national and international markets already in this project or in separate development projects. Primary, waste activated, tertiary and deinking sludge from pulp and paper industry and municipal waste activated sludge were the suspensions to be studied. Basic properties of these sludges have been determined by large number of analysing methods. Wood based components and chemical elements have been determined to clarify the raw material potential for biorefineries. Conventional fractionation techniques (decanter centrifuge, hydrocyclone, belt filter press and sieve bend) have been used to see how the sludge can be fractionated. Correlations of wood based components and dewatering properties have been studied especially for the waste activated sludge. The effects of wood based filter aids were studied on the dewatering properties of waste activated sludge. State of the art has been drawn up about the current utilisation of wastewater sludge. (orig.)

  20. Effects of additional fermented food wastes on nitrogen removal enhancement and sludge characteristics in a sequential batch reactor for wastewater treatment.

    Science.gov (United States)

    Zhang, Yongmei; Wang, Xiaochang C; Cheng, Zhe; Li, Yuyou; Tang, Jialing

    2016-07-01

    In order to enhance nitrogen removal from domestic wastewater with a carbon/nitrogen (C/N) ratio as low as 2.2:1, external carbon source was prepared by short-term fermentation of food wastes and its effect was evaluated by experiments using sequencing batch reactors (SBRs). The addition of fermented food wastes, with carbohydrate (42.8 %) and organic acids (24.6 %) as the main organic carbon components, could enhance the total nitrogen (TN) removal by about 25 % in contrast to the 20 % brought about by the addition of sodium acetate when the C/N ratio was equally adjusted to 6.6:1. The fermented food waste addition resulted in more efficient denitrification in the first anoxic stage of the SBR operation cycle than sodium acetate. In order to characterize the metabolic potential of microorganisms by utilizing different carbon sources, Biolog-ECO tests were conducted with activated sludge samples from the SBRs. As a result, in comparison with sodium acetate, the sludge sample by fermented food waste addition showed a greater average well color development (AWCD590), better utilization level of common carbon sources, and higher microbial diversity indexes. As a multi-organic mixture, fermented food wastes seem to be superior over mono-organic chemicals as an external carbon source. PMID:26988362

  1. SPONTANEOUS CATALYTIC WET AIR OXIDATION DURING PRE-TREATMENT OF HIGH-LEVEL RADIOACTIVE WASTE SLUDGE

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, D.; Herman, C.; Pareizs, J.; Bannochie, C.; Best, D.; Bibler, N.; Fellinger, T.

    2009-10-01

    Savannah River Remediation, LLC (SRR) operates the Defense Waste Processing Facility for the U.S. Department of Energy at the Savannah River Site. This facility immobilizes high-level radioactive waste through vitrification following chemical pretreatment. Catalytic destruction of formate and oxalate ions to carbon dioxide has been observed during qualification testing of non-radioactive analog systems. Carbon dioxide production greatly exceeded hydrogen production, indicating the occurrence of a process other than the catalytic decomposition of formic acid. Statistical modeling was used to relate the new reaction chemistry to partial catalytic wet air oxidation of both formate and oxalate ions driven by the low concentrations of palladium, rhodium, and/or ruthenium in the waste. Variations in process conditions led to increases or decreases in the total oxidative destruction, as well as partially shifting the preferred species undergoing destruction from oxalate ion to formate ion.

  2. Anaerobic Treatment of Municipal Solid Waste and Sludge for Energy Production and Recycling of Nutrients

    Science.gov (United States)

    Leinonen, S.

    This volume contains 18 papers presented at a Nordic workshop dealing with application of anaerobic decomposition processes on various types of organic wastes, held at the Siikasalmi Research and Experimental Station of the University of Joensuu on 1-2 Oct. 1992. Subject coverage of the presentations extends from the biochemical and microbiological principles of organic waste processing to descriptions and practical experiences of various types of treatment plants. The theoretical and experimental papers include studies on anaerobic and thermophilic degradation processes, methanogenesis, effects of hydrogen, treatment of chlorinated and phenolic compounds, and process modeling, while the practical examples range from treatment of various types of municipal, industrial, and mining wastes to agricultural and fish farm effluents. The papers provide technical descriptions of several biogas plants in operation. Geographically, the presentations span the Nordic and Baltic countries.

  3. Removal of phenolic endocrine disrupting compounds from waste activated sludge using UV, H2O2, and UV/H2O2 oxidation processes: Effects of reaction conditions and sludge matrix

    International Nuclear Information System (INIS)

    Removal of six phenolic endocrine disrupting compounds (EDCs) (estrone, 17β-estradiol, 17α-ethinylestradiol, estriol, bisphenol A, and 4-nonylphenols) from waste activated sludge (WAS) was investigated using ultraviolet light (UV), hydrogen peroxide (H2O2), and the combined UV/H2O2 processes. Effects of initial EDC concentration, H2O2 dosage, and pH value were investigated. Particularly, the effects of 11 metal ions and humic acid (HA) contained in a sludge matrix on EDC degradation were evaluated. A pseudo-first-order kinetic model was used to describe the EDC degradation during UV, H2O2, and UV/H2O2 treatments of WAS. The results showed that the degradation of the 6 EDCs during all the three oxidation processes fitted well with pseudo-first-order kinetics. Compared with the sole UV irradiation or H2O2 oxidation process, UV/H2O2 treatment was much more effective for both EDC degradation and WAS solubilization. Under their optimal conditions, the EDC degradation rate constants during UV/H2O2 oxidation were 45–197 times greater than those during UV irradiation and 11–53 times greater than those during H2O2 oxidation. High dosage of H2O2 and low pH were favorable for the degradation of EDCs. Under the conditions of pH = 3, UV wavelength = 253.7 nm, UV fluence rate = 0.069 mW cm−2, and H2O2 dosage = 0.5 mol L−1, the removal efficiencies of E1, E2, EE2, E3, BPA, and NP in 2 min were 97%, 92%, 95%, 94%, 89%, and 67%, respectively. The hydroxyl radical (·OH) was proved to take the most important role for the removal of EDCs. Metal ions in sludge could facilitate the removal of EDCs during UV/H2O2 oxidation. Fe, Ag, and Cu ions had more obvious effects compared with other metal ions. The overall role of HA was dependent on the balance between its competition as organics and its catalysis/photosensitization effects. These indicate that the sludge matrix plays an important role in the degradation of EDCs. - Highlights: • UV/H2O2 is effective in removing EDCs

  4. Removal of phenolic endocrine disrupting compounds from waste activated sludge using UV, H{sub 2}O{sub 2}, and UV/H{sub 2}O{sub 2} oxidation processes: Effects of reaction conditions and sludge matrix

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ai; Li, Yongmei, E-mail: liyongmei@tongji.edu.cn

    2014-09-15

    Removal of six phenolic endocrine disrupting compounds (EDCs) (estrone, 17β-estradiol, 17α-ethinylestradiol, estriol, bisphenol A, and 4-nonylphenols) from waste activated sludge (WAS) was investigated using ultraviolet light (UV), hydrogen peroxide (H{sub 2}O{sub 2}), and the combined UV/H{sub 2}O{sub 2} processes. Effects of initial EDC concentration, H{sub 2}O{sub 2} dosage, and pH value were investigated. Particularly, the effects of 11 metal ions and humic acid (HA) contained in a sludge matrix on EDC degradation were evaluated. A pseudo-first-order kinetic model was used to describe the EDC degradation during UV, H{sub 2}O{sub 2}, and UV/H{sub 2}O{sub 2} treatments of WAS. The results showed that the degradation of the 6 EDCs during all the three oxidation processes fitted well with pseudo-first-order kinetics. Compared with the sole UV irradiation or H{sub 2}O{sub 2} oxidation process, UV/H{sub 2}O{sub 2} treatment was much more effective for both EDC degradation and WAS solubilization. Under their optimal conditions, the EDC degradation rate constants during UV/H{sub 2}O{sub 2} oxidation were 45–197 times greater than those during UV irradiation and 11–53 times greater than those during H{sub 2}O{sub 2} oxidation. High dosage of H{sub 2}O{sub 2} and low pH were favorable for the degradation of EDCs. Under the conditions of pH = 3, UV wavelength = 253.7 nm, UV fluence rate = 0.069 mW cm{sup −2}, and H{sub 2}O{sub 2} dosage = 0.5 mol L{sup −1}, the removal efficiencies of E1, E2, EE2, E3, BPA, and NP in 2 min were 97%, 92%, 95%, 94%, 89%, and 67%, respectively. The hydroxyl radical (·OH) was proved to take the most important role for the removal of EDCs. Metal ions in sludge could facilitate the removal of EDCs during UV/H{sub 2}O{sub 2} oxidation. Fe, Ag, and Cu ions had more obvious effects compared with other metal ions. The overall role of HA was dependent on the balance between its competition as organics and its catalysis

  5. Polycyclic Aromatic Hydrocarbon Affects Acetic Acid Production during Anaerobic Fermentation of Waste Activated Sludge by Altering Activity and Viability of Acetogen.

    Science.gov (United States)

    Luo, Jingyang; Chen, Yinguang; Feng, Leiyu

    2016-07-01

    Till now, almost all the studies on anaerobic fermentation of waste activated sludge (WAS) for bioproducts generation focused on the influences of operating conditions, pretreatment methods and sludge characteristics, and few considered those of widespread persistent organic pollutants (POPs) in sludge, for example, polycyclic aromatic hydrocarbons (PAHs). Herein, phenanthrene, which was a typical PAH and widespread in WAS, was selected as a model compound to investigate its effect on WAS anaerobic fermentation for short-chain fatty acids (SCFAs) accumulation. Experimental results showed that the concentration of SCFAs derived from WAS was increased in the presence of phenanthrene during anaerobic fermentation. The yield of acetic acid which was the predominant SCFA in the fermentation reactor with the concentration of 100 mg/kg dry sludge was 1.8 fold of that in the control. Mechanism exploration revealed that the present phenanthrene mainly affected the acidification process of anaerobic fermentation and caused the shift of the microbial community to benefit the accumulation of acetic acid. Further investigation showed that both the activities of key enzymes (phosphotransacetylase and acetate kinase) involved in acetic acid production and the quantities of their corresponding encoding genes were enhanced in the presence of phenanthrene. Viability tests by determining the adenosine 5'-triphosphate content and membrane potential confirmed that the acetogens were more viable in anaerobic fermentation systems with phenanthrene, which resulted in the increased production of acetic acid. PMID:27267805

  6. Effect of thermal pretreatment on the biogas production and microbial communities balance during anaerobic digestion of urban and industrial waste activated sludge.

    Science.gov (United States)

    Ennouri, Hajer; Miladi, Baligh; Diaz, Soraya Zahedi; Güelfo, Luis Alberto Fernández; Solera, Rosario; Hamdi, Moktar; Bouallagui, Hassib

    2016-08-01

    The effect of thermal pre-treatment on the microbial populations balance and biogas production was studied during anaerobic digestion of waste activated sludge (WAS) coming from urban (US: urban sludge) and industrial (IS: industrial sludge) wastewater treatment plants (WWTP). The highest biogas yields of 0.42l/gvolatile solid (VS) removed and 0.37l/gVS removed were obtained with urban and industrial sludge pre-treated at 120°C, respectively. Fluorescent in situ hybridization (FISH) was used to quantify the major Bacteria and Archaea groups. Compared to control trails without pretreatment, Archaea content increased from 34% to 86% and from 46% to 83% for pretreated IS and US, respectively. In fact, the thermal pre-treatment of WAS enhanced the growth of hydrogen-using methanogens (HUMs), which consume rapidly the H2 generated to allow the acetogenesis. Therefore, the stable and better performance of digesters was observed involving the balance and syntrophic associations between the different microbial populations. PMID:27132226

  7. New insight into adsorption characteristics and mechanisms of the biosorbent from waste activated sludge for heavy metals.

    Science.gov (United States)

    Zhou, Yun; Zhang, Zhiqiang; Zhang, Jiao; Xia, Siqing

    2016-07-01

    The adsorption characteristics and mechanisms of the biosorbent from waste activated sludge were investigated by adsorbing Pb(2+) and Zn(2+) in aqueous single-metal solutions. A pH value of the metal solutions at 6.0 was beneficial to the high adsorption quantity of the biosorbent. The optimal mass ratio of the biosorbent to metal ions was found to be 2. A higher adsorption quantity of the biosorbent was achieved by keeping the reaction temperature below 55°C. Response surface methodology was applied to optimize the biosorption processes, and the developed mathematical equations showed high determination coefficients (above 0.99 for both metal ions) and insignificant lack of fit (p=0.0838 and 0.0782 for Pb(2+) and Zn(2+), respectively). Atomic force microscopy analyses suggested that the metal elements were adsorbed onto the biosorbent surface via electrostatic interaction. X-ray photoelectron spectroscopy analyses indicated the presence of complexation (between -NH2, -CN and metal ions) and ion-exchange (between -COOH and metal ions). The adsorption mechanisms could be the combined action of electrostatic interaction, complexation and ion-exchange between functional groups and metal ions. PMID:27372140

  8. Effects of pretreatments on thickened waste activated sludge and rice straw co-digestion: Experimental and modeling study.

    Science.gov (United States)

    Abudi, Zaidun Naji; Hu, Zhiquan; Xiao, Bo; Abood, Alkhafaji R; Rajaa, Nagham; Laghari, Mahmood

    2016-07-15

    In order to maximize the biogas production from thickened waste activated sludge (TWAS), co-digestion of TWAS and rice straw (RS) was studied and the application of thermal/thermo-alkaline and NaOH/H2O2 to TWAS and RS, respectively, was evaluated. The batch experiments were conducted at three different TWAS/RS (volume basis) ratios of 1:3, 1:1 and 3:1, respectively. Furthermore, the modified Gompertz model was introduced to predict the biogas yield and evaluate the kinetic parameters. The highest biogas production (409.2 L/kg VSadded) was achieved from co-digestion of TWASthermo-alkaline and RSNaOH at mixing ratio of 1:1, which is greater by 42.2% and 5.9% than that of digesting TWASthermo-alkaline, and RSNaOH alone, respectively. The highest VS removal rate was obtained from the co-digestion of TWASthermo-alkaline and RSNaOH at mixing ratio of 1:3, which is greater by 55.8% and 14.0% than those of mono-digestion. The modified Gompertz model (R(2): 0.993-0.998 and 0.993-0.999 for mono- and co-digestions, respectively) showed a good fit to the experimental results and the estimated parameters indicating that the pretreatments and co-digestion of substrates markedly improved the biogas production rate. PMID:27104588

  9. Start-up of an anaerobic dynamic membrane digester for waste activated sludge digestion: temporal variations in microbial communities.

    Directory of Open Access Journals (Sweden)

    Hongguang Yu

    Full Text Available An anaerobic dynamic membrane digester (ADMD was developed to digest waste sludge, and pyrosequencing was used to analyze the variations of the bacterial and archaeal communities during the start-up. Results showed that bacterial community richness decreased and then increased over time, while bacterial diversity remained almost the same during the start-up. Proteobacteria and Bacteroidetes were the major phyla. At the class level, Betaproteobacteria was the most abundant at the end of start-up, followed by Sphingobacteria. In the archaeal community, richness and diversity peaked at the end of the start-up stage. Principle component and cluster analyses demonstrated that archaeal consortia experienced a distinct shift and became stable after day 38. Methanomicrobiales and Methanosarcinales were the two predominant orders. Further investigations indicated that Methanolinea and Methanosaeta were responsible for methane production in the ADMD system. Hydrogenotrophic pathways might prevail over acetoclastic means for methanogenesis during the start-up, supported by specific methanogenic activity tests.

  10. Increased temperature in the thermophilic stage in temperature phased anaerobic digestion (TPAD) improves degradability of waste activated sludge.

    Science.gov (United States)

    Ge, Huoqing; Jensen, Paul D; Batstone, Damien J

    2011-03-15

    Two-stage temperature phased anaerobic digestion (TPAD) is an increasingly popular method to improve stabilisation of sewage waste activated sludge, which normally has inherently poor and slow degradation. However, there has been limited systematic analysis of the impact of the initial thermophilic stage (temperature, pH and retention time) on performance in the main mesophilic stage. In this study, we demonstrate a novel two-stage batch test method for TPAD processes, and use it to optimize operating conditions of the thermophilic stage in terms of degradation extent and methane production. The method determines overall degradability and apparent hydrolysis coefficient in both stages. The overall process was more effective with short pre-treatment retention times (1-2 days) and neutral pH compared to longer retention time (4 days) and low pH (4-5). Degradabilities and apparent hydrolysis coefficients were 0.3-0.5 (fraction degradable) and 0.1-0.4d(-1), respectively, with a margin of error in each measurement of approximately 20% relative (95% confidence). Pre-treatment temperature had a strong impact on the whole process, increasing overall degradability from 0.3 to 0.5 as temperature increased from 50 to 65 °C, with apparent hydrolysis coefficient increasing from 0.1 to 0.4d(-1). PMID:21277081

  11. Hydrodynamic cavitation as a novel approach for pretreatment of oily wastewater for anaerobic co-digestion with waste activated sludge.

    Science.gov (United States)

    Habashi, Nima; Mehrdadi, Nasser; Mennerich, Artur; Alighardashi, Abolghasem; Torabian, Ali

    2016-07-01

    Application of hydrodynamic cavitation (HC) was investigated with the objective of biogas production enhancement from co-digestion of oily wastewater (OWW) and waste activated sludge (WAS). Initially, the effect of HC on the OWW was evaluated in terms of energy consumption and turbidity increase. Then, several mixtures of OWW (with and without HC pretreatment) and WAS with the same concentration of total volatile solid were prepared as a substrate for co-digestion. Following, several batch co-digestion trials were conducted. To compare the biogas production, a number of digestion trials were also conducted with a mono substrate (OWW or WAS alone). The best operating condition of HC was achieved in the shortest retention time (7.5 min) with the application of 3mm diameter orifice and maximum pump rotational speed. Biogas production from all co-digestion reactors was higher than the WAS mono substrate reactors. Moreover, biogas production had a direct relationship with OWW ratio and no major inhibition was observed in any of the reactors. The biogas production was also enhanced by HC pretreatment and almost all of the reactors with HC pretreatment had higher reaction rates than the reactors without pretreatment. PMID:26964961

  12. Decomposition of ammonia and hydrogen sulfide in simulated sludge drying waste gas by a novel non-thermal plasma.

    Science.gov (United States)

    Lu, Shengyong; Chen, Lu; Huang, Qunxing; Yang, Liqin; Du, Changming; Li, Xiaodong; Yan, Jianhua

    2014-12-01

    To efficiently clean NH3 and H2S contained in municipal sewage sludge drying waste gas, experiments were conducted with a novel gliding arc discharge plasma reactor. Important parameters including applied voltage and gas velocity which can strongly influence the removal efficiency, energy cost and by-products yields were investigated. Maximum removal efficiencies were all obtained at the applied voltage of 11 kV and gas velocity of 4.72 m s−1. When NH3 and H2S were treated together, the total energy cost decreased by 38%. NO and SO2 were observed as main decomposition by-products, and the presence of NH3 may inhibit the production of SO2 whose yield decreased from 223.8 to 27.8 mg m−3. Tests performed on lab scale reactor showed that gliding arc discharge is efficient in decreasing the NH3 and H2S concentrations, and experiments will also be conducted on a larger scale reactor in the future. PMID:25461948

  13. Optimization and microbial community analysis of anaerobic co-digestion of food waste and sewage sludge based on microwave pretreatment.

    Science.gov (United States)

    Zhang, Junya; Lv, Chen; Tong, Juan; Liu, Jianwei; Liu, Jibao; Yu, Dawei; Wang, Yawei; Chen, Meixue; Wei, Yuansong

    2016-01-01

    The effects of microwave pretreatment (MW) on co-digestion of food waste (FW) and sewage sludge (SS) have never been investigated. In this study, a series of mesophilic biochemical methane potential (BMP) tests were conducted to determine the optimized ratio of FW and SS based on MW, and the evolution of bacterial and archaeal community was investigated through high-throughput sequencing method. Results showed that the optimized ratio was 3:2 for co-digestion of FW and SS based on MW, and the methane production was 316.24 and 338.44mLCH4/gVSadded for MW-FW and MW-SS, respectively. The MW-SS was superior for methane production compared to MW-FW, in which accumulation of propionic acid led to the inhibition of methanogenesis. Proteiniborus and Parabacteroides were responsible for proteins and polysaccharides degradation for all, respectively, while Bacteroides only dominated in co-digestion. Methanosphaera dominated in MW-FW at the active methane production phase, while it was Methanosarcina in MW-SS and mono-SS. PMID:26496214

  14. Kinetic analysis of waste activated sludge hydrolysis and short-chain fatty acids production at pH 10

    Institute of Scientific and Technical Information of China (English)

    FENG Leiyu; YAN Yuanyuan; CHEN Yinguang

    2009-01-01

    The accumulation of short-chain fatty acids (SCFAs), a preferred carbon source for enhanced biological phosphorus removal microbes, was significantly improved when waste activated sludge (WAS) was fermented at pH 10. The kinetics of WAS hydrolysis and SCFAs production at pH 10 were investigated. It was observed that during WAS anaerobic fermentation at pH 10 the accumulation of SCFAs was limited by the hydrolysis process, and both the hydrolysis of WAS particulate COD and the accumulation of SCFAs followed first-order kinetics. The hydrolysis and SCFAs accumulation rate constants increased with a increasing of temperature from 10 to 35℃, which could be described by the Arrhenius equation. The kinetic data further indicated that SCFAs production at pH 10 was a biological process. Compared with the experiment of pH uncontrolled (blank test), both the rate constants of WAS hydrolysis and SCFAs accumulation at 20℃ were significantly improved when WAS was fermented at pH 10.

  15. Ethanol production of semi-simultaneous saccharification and fermentation from mixture of cotton gin waste and recycled paper sludge.

    Science.gov (United States)

    Shen, Jiacheng; Agblevor, Foster A

    2011-01-01

    Ethanol production from the steam-exploded mixture of 75% cotton gin waste and 25% recycled paper sludge in various conditions was investigated by semi-simultaneous saccharification and fermentation (SSSF) consisting of a pre-hydrolysis and a simultaneous saccharification and fermentation (SSF). Four cases were studied: 24-h pre-hydrolysis + 48-h SSF (SSSF 24), 12-h pre-hydrolysis + 60-h SSF (SSSF 12), 72-h SSF, and 48-h hydrolysis + 24-h fermentation (SHF). The ethanol concentration, yield, and productivity of SSSF 24 were higher than those of the other operations. A model of SSF was used to simulate the data for four components in SSF. The analysis of the reaction rates of cellobiose, glucose, cell, and ethanol using the model and the parameters from the experiments showed that there was a transition point of the rate-controlling step at which the cell growth control in the initial 2 h was changed to the cellobiose reaction control in later period during ethanol production of SSF from the mixture. PMID:20559849

  16. Management of cladding hulls and fuel hardware

    International Nuclear Information System (INIS)

    The reprocessing of spent fuel from power reactors based on chop-leach technology produces a solid waste product of cladding hulls and other metallic residues. This report describes the current situation in the management of fuel cladding hulls and hardware. Information is presented on the material composition of such waste together with the heating effects due to neutron-induced activation products and fuel contamination. As no country has established a final disposal route and the corresponding repository, this report also discusses possible disposal routes and various disposal options under consideration at present

  17. CLAD DEGRADATION - FEPS SCREENING ARGUMENTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Schreiner

    2004-10-21

    The purpose of this report is to evaluate and document the screening of the clad degradation features, events, and processes (FEPs) with respect to modeling used to support the Total System Performance Assessment-License Application (TSPA-LA). This report also addresses the effect of certain FEPs on both the cladding and the commercial spent nuclear fuel (CSNF), DOE-owned spent nuclear fuel (DSNF), and defense high-level waste (DHLW) waste forms, as appropriate to address the effects on multiple materials and both components (FEPs 2.1.09.09.0A, 2.1.09.11.0A, 2.1.11.05.0A, 2.1.12.02.0A, and 2.1.12.03.0A). These FEPs are expected to affect the repository performance during the postclosure regulatory period of 10,000 years after permanent closure. Table 1-1 provides the list of cladding FEPs, including their screening decisions (include or exclude). The primary purpose of this report is to identify and document the analysis, screening decision, and TSPA-LA disposition (for included FEPs) or screening argument (for excluded FEPs) for these FEPs related to clad degradation. In some cases, where a FEP covers multiple technical areas and is shared with other FEP reports, this report may provide only a partial technical basis for the screening of the FEP. The full technical basis for shared FEPs is addressed collectively by the sharing FEP reports. The screening decisions and associated TSPA-LA dispositions or screening arguments from all of the FEP reports are cataloged in a project-specific FEPs database.

  18. CLAD DEGRADATION - FEPS SCREENING ARGUMENTS

    International Nuclear Information System (INIS)

    The purpose of this report is to evaluate and document the screening of the clad degradation features, events, and processes (FEPs) with respect to modeling used to support the Total System Performance Assessment-License Application (TSPA-LA). This report also addresses the effect of certain FEPs on both the cladding and the commercial spent nuclear fuel (CSNF), DOE-owned spent nuclear fuel (DSNF), and defense high-level waste (DHLW) waste forms, as appropriate to address the effects on multiple materials and both components (FEPs 2.1.09.09.0A, 2.1.09.11.0A, 2.1.11.05.0A, 2.1.12.02.0A, and 2.1.12.03.0A). These FEPs are expected to affect the repository performance during the postclosure regulatory period of 10,000 years after permanent closure. Table 1-1 provides the list of cladding FEPs, including their screening decisions (include or exclude). The primary purpose of this report is to identify and document the analysis, screening decision, and TSPA-LA disposition (for included FEPs) or screening argument (for excluded FEPs) for these FEPs related to clad degradation. In some cases, where a FEP covers multiple technical areas and is shared with other FEP reports, this report may provide only a partial technical basis for the screening of the FEP. The full technical basis for shared FEPs is addressed collectively by the sharing FEP reports. The screening decisions and associated TSPA-LA dispositions or screening arguments from all of the FEP reports are cataloged in a project-specific FEPs database

  19. Biosorption of chromium, copper and zinc by wine-processing waste sludge: Single and multi-component system study

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Cheng-Chung [Department of Environmental Engineering, National Ilan University, Ilan, 260, Taiwan (China); Wang, Ming-Kuang, E-mail: mkwang@ntu.edu.tw [Department of Agricultural Chemistry, National Taiwan University, Taipei, 106, Taiwan (China); Chiou, Chyow-San; Li, Yuan-Shen [Department of Environmental Engineering, National Ilan University, Ilan, 260, Taiwan (China); Yang, Chia-Yi [Department of Chemical and Materials Engineering, Tamkang University, Tamsui, 251, Taiwan (China); Lin, Yu-An [Department of Animal Science, National Ilan University, Ilan, 260, Taiwan (China)

    2009-11-15

    Wine-processing waste sludge (WPWS) has been shown to have powerful potential for sorption of some heavy metals (i.e., chromium, lead and nickel) in single-component aqueous solutions. But although most industrial wastewater contains two or more toxic metals, there are few sorption studies on multicomponent metals by WPWS. This study has two goals: (i) conduct competitive adsorption using Cr, Cu and Zn as sorbates and examine their interaction in binary or ternary systems; and (ii) determine the effects of temperature on the kinetic sorption reaction. The sludge tested contained a high amount of organic matter (38%) and had a high cation exchange capacity (CEC, 255 cmol{sub c} kg{sup -1}). Infrared analysis reveals that carboxyl is the main functional group in this WPWS. The {sup 13}C NMR determination indicates alkyl-C and carboxyl-C are major organic functional groups. At steady state, there are about 40.4% (Cr), 35.0% (Cu) and 21.9% (Zn) sorbed in the initial 6.12 mM of single-component solutions. Only pseudo-second-order sorption kinetic model successfully describes the kinetics of sorption for all experimental metals. The rate constants, k{sub 2}, of Cr, Cu and Zn in single-component solutions are 0.016, 0.030 and 0.154 g mg{sup -1} min{sup -1}, respectively. The sorption of metals by WPWS in this competitive system shows the trend: Cr > Cu > Zn. Ions of charge, hydrated radius and electronic configuration are main factors affecting sorption capacity. The least sorption for Zn in this competitive system can be attributed to its full orbital and largest hydrated radius. Though the effect of temperature on Zn sorption is insignificant, high temperature favors the other metallic sorptions, in particular for Cr. However, the Cr sorption is lower than Cu at 10 deg. C. The Cr sorption by WPWS can be higher than that of Cu at 30 deg. and 50 deg. C.

  20. COMPUTER AIDED DESIGN OF WASTE WATER TREATMENT PLANT WITH ACTIVATED SLUDGE PROCESS

    OpenAIRE

    K. SUNDARA KUMAR

    2011-01-01

    There are two fundamental reasons for treatment of wastewater viz., prevention of pollution and thereby protecting the environment, and protecting the public health by safe guarding water supplies andpreventing the spread of water borne diseases. Proper design, construction together with good operation and maintenance are essential for waste water treatment plants (WWTP), in order to produce effluents which are satisfying the safe disposal standards prescribed by the regulatory authorities. I...

  1. Changes in microbial communities in green waste and sewage sludge composts following maturity

    International Nuclear Information System (INIS)

    Composting is an interesting way to valorize various bio wastes and is becoming an increasingly used soil amendment. compost is a product obtained after a humification process. However, compost utilization as amendment needs to know precisely its stability and maturity. since composting is mainly a microbial process, knowledge of the various microbial groups and their role in the process of bio-oxidation is essential. (Author)

  2. Thermophilic anaerobic co-digestion of sewage sludge with grease waste: Effect of long chain fatty acids in the methane yield and its dewatering properties

    International Nuclear Information System (INIS)

    Highlights: • Thermophilic anaerobic codigestion of sewage sludge and grease waste (GW) doubles methane yield. • High GW doses in the influent leads to instability and LCFA accumulation in the effluent. • GW addition promotes acetoclastic activity whilst worsening the hydrogenothrophic activity. • The mesophilic codigestion with GW performs better than the thermophilic one. - Abstract: Thermophilic co-digestion of sewage sludge with three different doses of trapped grease waste (GW) from the pre-treatment of a WWTP has been assessed in a CSTR bench-scale reactor. After adding 12% and 27% of grease waste (on COD basis), the organic loading rate increased from 2.2 to 2.3 and 2.8 kgCOD m−3 d−1 respectively, and the methane yield increased 1.2 and 2.2 times. Further GW increase (37% on COD basis) resulted in an unstable methane yield and in long chain fatty acids (LCFA) accumulation. Although this inestability, the presence of volatile fatty acids in the effluent was negligible, showing good adaptation to fats of the thermophilic biomass. Nevertheless, the presence of LCFA in the effluent worsens its dewatering properties. Specific methanogenic activity tests showed that the addition of grease waste ameliorates the acetoclastic activity in detriment of the hydrogenotrophic activity, and suggests that the tolerance to LCFA can be further enhanced by slowly increasing the addition of lipid-rich materials

  3. Sludge dewatering in a decanter centrifuge aided by cationic flocculant Praestol 855BS and essential oil of waste orange peels

    OpenAIRE

    Kowalczyk Anna; Piecuch Tadeusz

    2016-01-01

    In the study the comparative analysis of test results of drainage of municipal wastewater sludge was conducted with the use of flocculant Praestol 855BS and the mixture of flocculant Praestol 855BS 50% + orange essential oil 50%, as the reagents supporting this process. It was also attempted to reduce unpleasant smells exuding from the drained sludge.

  4. Sludge dewatering in a decanter centrifuge aided by cationic flocculant Praestol 855BS and essential oil of waste orange peels

    Directory of Open Access Journals (Sweden)

    Kowalczyk Anna

    2016-03-01

    Full Text Available In the study the comparative analysis of test results of drainage of municipal wastewater sludge was conducted with the use of flocculant Praestol 855BS and the mixture of flocculant Praestol 855BS 50% + orange essential oil 50%, as the reagents supporting this process. It was also attempted to reduce unpleasant smells exuding from the drained sludge.

  5. Recycle technologies for waste sludge, pulp reject and waste solid in pulping and ifber preparation%制浆与纤维制备污泥和渣浆处理及固体废料回收技术

    Institute of Scientific and Technical Information of China (English)

    Michael Waupotitsch

    2014-01-01

    安德里茨在制浆污泥和渣浆处理及固体废料回收技术装备方面走在世界前列。本文主要介绍了安德里茨如何将这些污泥、固体废料变成燃料、能源的先进理念和技术装备,以及最新应用情况。%Andritz has ranked at the ifrst row in the world in technology and equipment for the treatment of pulping sludge, pulp reject and the recycle of solid waste. In this article was introduced the advanced ideas and facilities how to change the sludge and the waste into fuel and power.

  6. Effect of hydraulic retention time and sludge recirculation on greenhouse gas emission and related microbial communities in two-stage membrane bioreactor treating solid waste leachate.

    Science.gov (United States)

    Nuansawan, Nararatchporn; Boonnorat, Jarungwit; Chiemchaisri, Wilai; Chiemchaisri, Chart

    2016-06-01

    Methane (CH4) and nitrous oxide (N2O) emissions and responsible microorganisms during the treatment of municipal solid waste leachate in two-stage membrane bioreactor (MBR) was investigated. The MBR system, consisting of anaerobic and aerobic stages, were operated at hydraulic retention time (HRT) of 5 and 2.5days in each reactor under the presence and absence of sludge recirculation. Organic and nitrogen removals were more than 80% under all operating conditions during which CH4 emission were found highest under no sludge recirculation condition at HRT of 5days. An increase in hydraulic loading resulted in a reduction in CH4 emission from anaerobic reactor but an increase from the aerobic reactor. N2O emission rates were found relatively constant from anaerobic and aerobic reactors under different operating conditions. Diversity of CH4 and N2O producing microorganisms were found decreasing when hydraulic loading rate to the reactors was increased. PMID:26860618

  7. Verification Of The Defense Waste Processing Facility's (DWPF) Process Digestion Methods For The Sludge Batch 8 Qualification Sample

    International Nuclear Information System (INIS)

    This report contains the results and comparison of data generated from inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis of Aqua Regia (AR), Sodium Peroxide/Sodium Hydroxide Fusion Dissolution (PF) and Cold Chem (CC) method digestions and Cold Vapor Atomic Absorption analysis of Hg digestions from the DWPF Hg digestion method of Sludge Batch 8 (SB8) Sludge Receipt and Adjustment Tank (SRAT) Receipt and SB8 SRAT Product samples. The SB8 SRAT Receipt and SB8 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB8 Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 7b (SB7b), to form the SB8 Blend composition

  8. Verification Of The Defense Waste Processing Facility's (DWPF) Process Digestion Methods For The Sludge Batch 8 Qualification Sample

    Energy Technology Data Exchange (ETDEWEB)

    Click, D. R.; Edwards, T. B.; Wiedenman, B. J.; Brown, L. W.

    2013-03-18

    This report contains the results and comparison of data generated from inductively coupled plasma – atomic emission spectroscopy (ICP-AES) analysis of Aqua Regia (AR), Sodium Peroxide/Sodium Hydroxide Fusion Dissolution (PF) and Cold Chem (CC) method digestions and Cold Vapor Atomic Absorption analysis of Hg digestions from the DWPF Hg digestion method of Sludge Batch 8 (SB8) Sludge Receipt and Adjustment Tank (SRAT) Receipt and SB8 SRAT Product samples. The SB8 SRAT Receipt and SB8 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB8 Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 7b (SB7b), to form the SB8 Blend composition.

  9. Hydrogenous Gas Production through Reactions among Supercritical Water, Ironmaking Sludge, and Steelmaking Slag and Recycling of Wastes from Integrated Steel Mills

    Science.gov (United States)

    Hayashi, Shoji

    Automobile Shredder Residue (ASR) and Refuse derived fuels (not carbonized and carbonized: YRDF and RDF) as carbonaceous wastes were reacted isothermally with sub-supercritical water (600-695°C, 200 atm) together with a CO2 fixation reagent Ca(OH)2 inside a closed metallic tube reactor (7cm3). Product gas mainly consisted of hydrogen gas and a little methane gas except YRDF. As a whole, gas generated more in order ASR, YRDF, and RDF. Addition of catalysis NaOH or KOH made product gas increase more. KOH was more effective to product gas than NaOH. X-ray diffraction followed that Ca(OH)2 and CaCO3 existed mainly in residues after reaction tests with a CO2 fixation reagent Ca(OH)2 or CaO. Therefore, it was supposed that an overall chemical reaction took place as shown below. BOF steelmaking slag for CO2 fixation provided maximum gas generation 1.42 times as much as molar carbon in a RDF sample with KOH. C + H2O + Ca(OH)2 = CaCO3 + 2H2 Two kinds of wastes from integrated steel mills (sludge from mill scale and activated sludge) were each reacted with supercritical water (600-650°C, 200 atm). Both sludges were effective to generate hydrogenous gas. It was found that harmful cyan in the latter sludge mostly decomposed after reaction. Also, the crushing strength after curing the steelmaking slag bearing residue briquette was not as high as that from Portland cement.

  10. Comment on "Synergistic co-digestion of solid-organic-waste and municipal-sewage-sludge: 1 plus 1 equals more than 2 in terms of biogas production and solids reduction" [Water Research 87, 416-423].

    Science.gov (United States)

    Insam, Heribert; Markt, Rudolf

    2016-05-15

    Co-digestion of organic waste and sewage sludge enhances biogas production and reduces the mass of remaining solids. This phenomenon of enhanced organic matter decomposition by adding labile substrate is known from other habitats like soils and sediments where it is called priming effect. It is thus suggested to adopt the term priming effect also in environmental biotechnology, and in particular for biomethanisation of wastewater sludges by the addition of energy-rich co-substrates. PMID:26965899

  11. Ash and sludge covering of mine waste - Final report. Benefits and/or risks using ash and sludge for covering of weathered mine waste; Aska och roetslam som taet- och taeckskikt foer vittrat gruvavfall - Slutrapport. Foerdelar och/eller risker med att anvaenda aska och slam som taet- och taeckskikt foer vittrat gruvavfall

    Energy Technology Data Exchange (ETDEWEB)

    Baeckstroem, Mattias; Karlsson, Ulrika [Oerebro Univ. (Sweden). Man-Technology-Environment Research Centre

    2006-02-15

    One of the main sources for metal pollution in Sweden is mine waste. One way to decrease the leaching of metals from mine waste areas are covering which decreases the volume of acid drainage. There is a shortage of appropriate materials to use for covering and excavation of till and clay from the environment might cause damages on the landscape. Previous studies have demonstrated that sludge and ashes are suitable materials for covering of waste deposits. When covering mine waste with ash and sludge various positive effects would arise, since the production of drainage water decreases as well as the pH increases due to the high buffer capacity of the ash. In Ervalla outside Oerebro an area with mine waste (tailings) has been covered with ash and sludge. This area gives a unique possibility to study benefits and/or risks with the covering of mine waste with ash and sludge. Unfortunately, the covering was not, from the start, carried out in a way that made it possible to evaluate the data. For instance, data about the surface and groundwater quality prior to the covering is lacking. Sulphidic minerals are also very common in the area, giving rise to acidic groundwater from other parts of the area, which haven't been remediated. This report is a final report where all phases are presented (phase 1 and 2). Focus in phase 1 has been on characterization of the material that has been used for covering and initiation of a monitoring program. In phase 2 focus has been on evaluation of monitoring data and the pros and cons of the deposit regarding the environment. Preliminary findings indicate that that the covering increases the leaching of some metals whereas the leaching of some metals decreases. An increase was observed for pH, calcium, potassium, sodium, arsenic, barium, chromium and copper. A decrease in the concentration of iron, nickel, cobalt, lead and zinc was observed. Other benefits with the remediation is also discussed (increased plant growth and an area

  12. SOLIDIFICATION OF THE HANFORD LAW WASTE STREAM PRODUCED AS A RESULT OF NEAR-TANK CONTINUOUS SLUDGE LEACHING AND SODIUM HYDROXIDE RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    Reigel, M.; Johnson, F.; Crawford, C.; Jantzen, C.

    2011-09-20

    The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge can be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the

  13. Solidification Of The Hanford Law Waste Stream Produced As A Result Of Near-Tank Continuous Sludge Leaching And Sodium Hydroxide Recovery

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge can be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the

  14. Enhanced hydrogen production from waste activated sludge by cascade utilization of organic matter in microbial electrolysis cells.

    Science.gov (United States)

    Lu, Lu; Xing, Defeng; Liu, Bingfeng; Ren, Nanqi

    2012-03-15

    Fermentative hydrogen production from waste activated sludge (WAS) has low H2 yield because WAS contains limited amounts of carbohydrate suitable for use by hydrogen-producing bacteria. Here, augmentation of hydrogen production from WAS by microbial electrolysis cells (MECs) was implemented. H2 yields of 3.89±0.39 mg-H2/g-DS (5.67±0.61 mg-H2/g-VSS) from raw WAS and 6.78±0.94 mg-H2/g-DS (15.08±1.41 mg-H2/g-VSS) from alkaline-pretreated WAS were obtained in the two-chamber MECs (TMECs). This was several times higher than yields obtained previously by fermentation. Single-chamber MECs (SMECs) with low internal resistance showed a H2 production rate that 13 times that of TMECs with similar H2 yield when alkaline-pretreated WAS was used. However, methanogenesis was detected after several batch cycles. A yield balance calculation revealed that carbohydrates were not the only substrates for electrohydrogenesis. Protein and its acidification products, such as volatile fatty acids are also responsible for a portion of H2 generation in MEC. Characterization of WAS in TMECs by three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy with parallel factor analysis indicated that electrohydrogenesis reacted on the extracellular polymeric substances and intracellular substances of WAS. Cascade utilization of organic matter in MECs increased hydrogen production from WAS. MECs showed high hydrogen yield from WAS, fewer H2 sinks, and insensitivity to temperature. Optimizing MEC configurations and operation conditions and improving the pretreatment processes of WAS are necessary before practical application can take place on a large scale. PMID:22197264

  15. Analyses by the Defense Waste Processing Facility Laboratory of Thorium Glasses from the Sludge Batch 6 Variability Study

    International Nuclear Information System (INIS)

    The Savannah River Remediation (SRR) Defense Waste Processing Facility (DWPF) is currently processing Sludge Batch 6 (SB6) with Frit 418. At times during the processing of this glass system, thorium is expected to be at concentrations in the final wasteform that make it a reportable element for the first time since startup of radioactive operations at the DWPF. The Savannah River National Laboratory (SRNL) supported the qualification of the processing of this glass system at the DWPF. A recommendation from the SRNL studies was the need for the DWPF Laboratory to establish a method to measure thorium by Inductively Coupled Plasma - Atomic Emission Spectroscopy (ICPAES). This recommendation led to the set of thorium-bearing glasses from the SB6 Variability Study (VS) being submitted to the DWPF Laboratory for chemical composition measurement. The measurements were conducted by the DWPF Laboratory using the sodium peroxide fusion preparation method routinely employed for analysis of samples from the Slurry Mix Evaporator (SME). These measurements are presented and reviewed in this report. The review indicates that the measurements provided by the DWPF Laboratory are comparable to those provided by Analytical Development's laboratory at SRNL for these same glasses. As a result, the authors of this report recommend that the DWPF Laboratory begin using its routine peroxide fusion dissolution method for the measurement of thorium in SME samples of SB6. The purpose of this technical report is to present the measurements generated by the DWPF Laboratory for the SB6 VS glasses and to compare the measurements to the targeted compositions for these VS glasses as well as to SRNL's measurements (both sets, targeted and measured, of compositional values were reported by SRNL in (2)). The goal of these comparisons is to provide information that will lead to the qualification of peroxide fusion dissolution as a method for the measurement by the DWPF Laboratory of thorium in SME

  16. Behaviour of Main Microbiological Parameters And of Enteric Microorganisms During the Composting of Municipal Solid Wastes and Sewage Sludge in A Semi-Industrial Composting Plant

    Directory of Open Access Journals (Sweden)

    O. Fourti

    2008-01-01

    Full Text Available This study was focused on the microbiological aspects of composting and on the behaviour of main prevalent microbial communities (non-pathogenic and selected pathogenic bacteria during the composting process of municipal solid wastes and sewage sludge in a semi-industrial composting plant. Results showed that the dehydrogenase activity and Biomass C / Biomass N ratio showed a noticeable increase in the two windrows W1 (100% of municipal solid wastes and W2 (60% of municipal solid wastes and 40% of dried sewage sludge during the thermophilic phase (≥45°C for 100 days and marked a high microbial activity during this period of the composting process. During the thermophilic phase, the removal of faecal indicator bacteria is in order of 2 Ulog10, and a total absence of Staphylococcus aureus and Salmonella was observed. The re-emergence of faecal indicator bacteria at the end of the composting progress (cooling step could constitute a major problem for the agricultural use of compost.

  17. Co-treatment of fruit and vegetable waste in sludge digesters: Chemical and spectroscopic investigation by fluorescence and Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Provenzano, Maria Rosaria; Cavallo, Ornella; Malerba, Anna Daniela; Di Maria, Francesco; Cucina, Mirko; Massaccesi, Luisa; Gigliotti, Giovanni

    2016-04-01

    In a previous work co-digestion of food waste and sewage sludge was performed in a pilot apparatus reproducing operating conditions of an existing full scale digester and processing waste mixed sludge (WMS) and fruit and vegetable waste (FVW) at different organic loading rates. An analysis of the relationship among bio-methane generation, process stability and digestate phytotoxicity was conducted. In this paper we considered humification parameters and spectroscopic analysis. Humification parameters indicated a higher not humified fraction (NH) and a lower degree of humification (DH) of FVW with respect to WMS (NH=19.22 and 5.10%; DH=36.65 and 61.94% for FVW and WMS, respectively) associated with their different chemical compositions and with the stabilization process previously undergone by sludge. FVW additions seemed to be favourable from an agronomical point of view since a lower percentage of organic carbon was lost. Fourier transform infrared spectra suggested consumption of aliphatics associated with rising in bio-methane generation followed by accumulation of aliphatics and carboxylic acids when the biogas production dropped. The trend of peaks ratios can be used as an indicator of the process efficiency. Fluorescence intensity of peak B associated with tryptophan-like substances and peak D associated with humic-like substances observed on tridimensional Excitation Emission Matrix maps increased up to sample corresponding to the highest rate of biogas production. Overall spectroscopic results provided evidence of different chemical pathways of anaerobic digestion associated with increasing amount of FVW which led to different levels of biogas production. PMID:26946935

  18. Solids Control in Sludge Pretreatment

    International Nuclear Information System (INIS)

    Sludge pretreatment will likely involve washing, followed by caustic or acidic leaching and washing of sludge residues after leaching. The principal goal of pretreatment is to obtain a low-volume high-activity waste stream and a high-volume low-activity waste stream. Also, some waste constituents such as chromium and phosphate can be included in glass formulations only at very low concentrations; therefore, it is desirable to remove them from high-level waste streams. Two aspects of sludge treatment and subsequent separations should be well delineated and predictable: (1) the distribution of chemical species between aqueous solutions and solids and (2) potential problems due to chemical interactions that could result in process difficulties or safety concerns.Before any treatment technology is adopted, it must be demonstrated that the process can be carried out as planned. Three pretreatment methods were considered in the Tri-Party (Washington State Ecology, U.S. Environmental Protection Agency, and U.S. Department of Energy) negotiations: (1) sludge washing with corrosion- inhibiting water, (2) Enhanced Sludge Washing, and (3)acidic dissolution with separations processes. Enhanced Sludge Washing is the baseline process. In Enhanced Sludge Washing, sludge is first washed with corrosion-inhibiting water; it is then leached with caustic (sodium hydroxide solution) and washed again with corrosion- inhibiting water. The initial concern is whether a pretreatment technique is effective in separating sludge components. This can be evaluated by bench-scale tests with sludge specimens from underground storage tanks. The results give data on the distribution of important species such as aluminum, phosphate, and radionuclides between wash and leach solutions and solid sludge residues

  19. Solids Control in Sludge Pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Beahm, E.C., Weber, C.F., Hunt, R.D., Dillow, T.A.

    1997-12-31

    Sludge pretreatment will likely involve washing, followed by caustic or acidic leaching and washing of sludge residues after leaching. The principal goal of pretreatment is to obtain a low-volume high-activity waste stream and a high-volume low-activity waste stream. Also, some waste constituents such as chromium and phosphate can be included in glass formulations only at very low concentrations; therefore, it is desirable to remove them from high-level waste streams. Two aspects of sludge treatment and subsequent separations should be well delineated and predictable: (1) the distribution of chemical species between aqueous solutions and solids and (2) potential problems due to chemical interactions that could result in process difficulties or safety concerns.Before any treatment technology is adopted, it must be demonstrated that the process can be carried out as planned. Three pretreatment methods were considered in the Tri-Party (Washington State Ecology, U.S. Environmental Protection Agency, and U.S. Department of Energy) negotiations: (1) sludge washing with corrosion- inhibiting water, (2) Enhanced Sludge Washing, and (3)acidic dissolution with separations processes. Enhanced Sludge Washing is the baseline process. In Enhanced Sludge Washing, sludge is first washed with corrosion-inhibiting water; it is then leached with caustic (sodium hydroxide solution) and washed again with corrosion- inhibiting water. The initial concern is whether a pretreatment technique is effective in separating sludge components. This can be evaluated by bench-scale tests with sludge specimens from underground storage tanks. The results give data on the distribution of important species such as aluminum, phosphate, and radionuclides between wash and leach solutions and solid sludge residues.

  20. Enhanced sludge washing evaluation plan

    International Nuclear Information System (INIS)

    The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices

  1. Characterization, Leaching, and Filtration Testing for Bismuth Phosphate Sludge (Group 1) and Bismuth Phosphate Saltcake (Group 2) Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Lumetta, Gregg J.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn; Edwards, Matthew K.; Fiskum, Sandra K.; Hallen, Richard T.; Jagoda, Lynette K.; Jenson, Evan D.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Shimskey, Rick W.; Sinkov, Sergey I.; Snow, Lanee A.

    2009-02-19

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan.() The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. The actual waste-testing program included homogenizing the samples by group, characterizing the solids and aqueous phases, and performing parametric leaching tests. Two of the eight defined groups—bismuth phosphate sludge (Group 1) and bismuth phosphate saltcake (Group 2)—are the subjects of this report. The Group 1 waste was anticipated to be high in phosphorus and was implicitly assumed to be present as BiPO4 (however, results presented here indicate that the phosphate in Group 1 is actually present as amorphous iron(III) phosphate). The Group 2 waste was also anticipated to be high in phosphorus, but because of the relatively low bismuth content and higher aluminum content, it was anticipated that the Group 2 waste would contain a mixture of gibbsite, sodium phosphate, and aluminum phosphate. Thus, the focus of the Group 1 testing was on determining the behavior of P removal during caustic leaching, and the focus of the Group 2 testing was on the removal of both P and Al. The waste-type definition, archived sample conditions, homogenization activities, characterization (physical, chemical, radioisotope, and crystal habit), and caustic leaching behavior as functions of time, temperature, and hydroxide concentration are discussed in this report. Testing was conducted according to TP-RPP-WTP-467.

  2. Process optimization of biogas production at Nemščak biogas plant by pre-treatment of the substrate and combining with waste sludge

    OpenAIRE

    Žitek, Filip

    2015-01-01

    The purpose of this thesis is to increase the amount of biogas produced by pre-treatment of the substrate and combining with waste sludge. For anaerobic digestion of different substrates, we used a pilot reactor to determine the biogas potential at Nemščak biogas plant. The pilot reactor was built in 2009 for the purpose of testing new substrates in the process of biogas production. The pilot reactor has a working volume of 2000 litres; there is a gas tank above it with the volume of 500 litr...

  3. Anaerobic co-digestion of vegetal oil and thickened waste-activated sludge: Effects on biogas production and microbial community structure

    OpenAIRE

    Lauwers, Joost; Appels, Lise; Ruyters, Stefan; Busschaert, Pieter; Lievens, Bart; Van Impe, Jan; Dewil, Raf

    2013-01-01

    Thickened waste-activated sludge (tWAS) was co-digested with vegetal oil in a continuous 50 L digester. Compared to a digester fed with only tWAS, the biogas production increased as expected due to the addition of oil: about 60 % for an oil load of 10-15 % of the volatile solids (VS) load and a triplication for an oil load of 37-44%. Using 454 pyrosequencing, the microbial community structure was analyzed and visualised in a non-metric multidimensional scaling. The community of the Bacte...

  4. Determination of F-, Cl-, NO2-, Br-, PO43- and SO42- ions in high-level liquid waste and sludge

    International Nuclear Information System (INIS)

    The determination of anions F-, Cl-, NO2-, Br-, PO3-4 and SO42- in high-level liquid waste (HLLW) and high-level radioactive sludge (HLRS) by ion chromatography (IC) is studied in detail. Potentially interfering cations are removed by pretreatment with a cation exchange resin column. A 104 times decrease in radioactivity is achieved by this step. Borate-gluconic acid solution is used as an eluent for IC to alter the peak sequence, and thus suppress the influence of NO3- ion. The method has been successfully used for determination of various anions HLLW and HLRS

  5. Activated Sludge and other Aerobic Suspended Culture Processes.

    Science.gov (United States)

    Li, Chunying; Wei, Li; Chang, Chein-Chi; Zhang, Yuhua; Wei, Dong

    2016-10-01

    This is a literature review for the year 2015 and contains information specifically associated with suspended growth processes including activated sludge, upflow anaerobic sludge blanket, and sequencing batch reactors. The review encompasses modeling and kinetics, nutrient removal, system design and operation. Compared to past reviews, many topics show increase in activity in 2015. These include, fate and effect of xenobiotics, industrial wastes treatment with sludge, and pretreatment for the activated sludge. These topics are referred to the degradation of constituents in activated sludge. Other sections include population dynamics, process microbiology give an insight into the activated sludge. The subsection in industrial wastes: converting sewage sludge into biogases was also mentioned. PMID:27620082

  6. Sludge pretreatment chemistry evaluation: Enhanced sludge washing separation factors

    International Nuclear Information System (INIS)

    This report presents the work conducted in Fiscal Year 1994 by the Sludge Pretreatment Chemistry Evaluation Subtask for the Tank Waste Remediation System (TWRS) Tank Waste Treatment Science Task. The main purpose of this task, is to provide the technical basis and scientific understanding to support TWRS baseline decisions and actions, such as the development of an enhanced sludge washing process to reduce the volume of waste that will require high-level waste (HLW) vitrification. One objective within the Sludge Pretreatment Chemistry Evaluation Subtask was to establish wash factors for various SST (single-shell tank) sludges. First, analytical data were compiled from existing tank waste characterization reports. These data were summarized on tank-specific worksheets that provided a uniform format for reviewing and comparing data, as well as the means to verify whether the data set for each tank was complete. Worksheets were completed for 27 SST wastes. The analytical water wash data provided tank-specific information about the fraction of each component that dissolves with water, i.e., an estimate of tank-specific wash factors for evaluating tank-by-tank processing. These wash data were then used collectively to evaluate some of the wash factors that are assumed for the overall SST waste inventory; specifically, wash factors for elements that would be found primarily in sludges. The final step in this study was to incorporate the characterization and wash factor data into a spreadsheet that provides insight into the effect of enhanced sludge washing on individual tank sludges as well as for groups of sludges that may be representative of different waste types. Spreadsheet results include the estimated mass and percentage of each element that would be removed with washing and leaching. Furthermore, estimated compositions are given of the final wash and leach streams and residual solids, in terms of both concentration and dry weight percent

  7. Effective anaerobic biodegradation of municipal solid waste fresh leachate using a novel pilot-scale reactor: comparison under different seeding granular sludge.

    Science.gov (United States)

    Luo, Jinghuan; Zhou, Jizhi; Qian, Guangren; Liu, Jianyong

    2014-08-01

    A novel integrated internal and external circulation (IIEC) reactor was developed for anaerobic biodegradation of municipal solid waste (MSW) fresh leachate with chemical oxygen demand (COD) between 40,000 and 60,000mg/l. The pilot-scale IIEC reactor was inoculated with two kinds of granular sludge from paper mill (SPM) and from citric acid factory (SCF), respectively. The bio-treating capacity in contaminant removal and biogas production performed much superior to others' results, principally attributed to appropriate configuration modification. Compared to SCF, much higher organic loading rate (40.5 vs 23.0kgCOD/m(3)d) and COD removal efficiency (>80% vs 60-75%) were achieved for the reactor with SPM. For methane production, 11.77 or ∼6m(3)STP/m(3)d of rate and 66-85% of content were observed with SPM or SCF, respectively. Due to better sludge concentrations and methanogenic activity, these findings indicate the anaerobic reactor could effectively bio-treat MSW leachate for methane generation, especially inoculated with granular sludge derived from leachate-like-wastewater. PMID:24755395

  8. Waste-Activated Sludge Fermentation for Polyacrylamide Biodegradation Improved by Anaerobic Hydrolysis and Key Microorganisms Involved in Biological Polyacrylamide Removal

    OpenAIRE

    Xiaohu Dai; Fan Luo; Dong Zhang; Lingling Dai; Yinguang Chen; Bin Dong

    2015-01-01

    During the anaerobic digestion of dewatered sludge, polyacrylamide (PAM), a chemical conditioner, can usually be consumed as a carbon and nitrogen source along with other organic matter (e.g., proteins and carbohydrates in the sludge). However, a significant accumulation of acrylamide monomers (AMs) was observed during the PAM biodegradation process. To improve the anaerobic hydrolysis of PAM, especially the amide hydrolysis process, and to avoid the generation of the intermediate product AM,...

  9. Superfund Record of Decision (EPA Region 4): Oak Ridge Reservation (USDOE) (sludge removal from the Gunite and Associated Tanks Operable Unit, Waste Area Grouping 1), Oak Ridge, TN, September 2, 1997

    International Nuclear Information System (INIS)

    This record of decision (ROD) presents the selected interim remedial action for removing mixed transuranic (TRU) waste sludge from eight tanks in the Gunite and Associated Tanks (GAAT) Operable Unit (OU). The tanks are located in Oak Ridge National Laboratory (ORNL) Waste Area Grouping (WAG) 1. The selected interim remedial includes removal of the sludge and subsequent transfer to the Melton Valley Storage Tanks (MVST). The plans for removing GAAT sludge will be included in the remedial design and remedial action documentation. The selected remedy was developed considering the TRU waste strategy (i.e., consolidate, treat, and ship waste to the Waste Isolation Pilot Plant (WIPP) or the Nevada Test Site (NTS)) and the strategy to evaluate residual contamination in the OU after waste removal as part of the Bethel Valley Watershed remediation. After removal of sludge, samples of the tank shell will be collected to provide contaminant levels for consideration during future closure evaluations, as part of the Bethel Valley Watershed remediation

  10. Hybrid Sludge Modeling in Water Treatment Processes

    OpenAIRE

    Brenda, Marian

    2015-01-01

    Sludge occurs in many waste water and drinking water treatment processes. The numeric modeling of sludge is therefore crucial for developing and optimizing water treatment processes. Numeric single-phase sludge models mainly include settling and viscoplastic behavior. Even though many investigators emphasize the importance of modeling the rheology of sludge for good simulation results, it is difficult to measure, because of settling and the viscoplastic behavior. In this thesis, a new method ...

  11. ANSTO's waste forms for the 31. century

    International Nuclear Information System (INIS)

    ANSTO waste form development for high-level radioactive waste is directed towards practical applications, particularly problematic niche wastes that do not readily lend themselves to direct vitrification. Integration of waste form chemistry and processing method is emphasised. Some longstanding misconceptions about titanate ceramics are dealt with. We have a range of titanate-bearing waste form products aimed at immobilisation of tank wastes and sludges, actinide-rich wastes, INEEL calcines and Na-bearing liquid wastes, Al-rich wastes arising from reprocessing of Al-clad fuels, Mo-rich wastes arising from reprocessing of U-Mo fuels, partitioned Cs-rich wastes, and 99Tc. Waste form production techniques cover hot isostatic and uniaxial pressing, sintering, and cold-crucible melting, and these are strongly integrated into waste form design. Speciation and leach resistance of Cs and alkalis in cementitious products and geo-polymers are being studied. Recently we have embarked on studies of candidate inert matrix fuels for Pu burning. We also have a considerable program directed at basic understanding of the waste forms in regard to crystal chemistry, dissolution behaviour in aqueous media, radiation damage effects and optimum processing techniques. (authors)

  12. Fractionation and business potential from sludge (Pafrak)

    Energy Technology Data Exchange (ETDEWEB)

    Pirkonen, P.; Kylloenen, H. (VTT Technical Research Centre of Finland, Jyvaeskylae (Finland)); Niinimaeki, J.; Oksanen, J. (Univ. of Oulu (Finland))

    2008-07-01

    Wastewater sludge contains valuable components which can be recycled and converted to secondary raw material. High water content of sludge can hinder the further processing. Dry solids content of waste activated sludge after dewatering can be as low as 12-20% and even lower for tertiary sludge. This research aims with better knowledge of sludge and fractionation to generation of potential business ideas which could lead to new sludge based products and services in national and international markets already in this project or in separate development projects. Municipal waste activated sludge and deinking, primary, waste activated and tertiary sludge from pulp and paper industry are the suspensions to be studied. Basic properties of these sludges have been determined by large number of analysing methods. Dewatering properties, which are one of the key topics, have been studied with a novel flocculation/filtration device. Conventional fractionation equipment (decanter centrifuge, hydrocyclone. filter belt press and sieve bend) have been used to see how the sludge could be fractionated. State of the art has been drawn up about the current utilisation of wastewater sludge. One of the key issues in future research is how to affect the binding forces between different substances in sludge. (orig.)

  13. K basins sludge removal sludge pretreatment system

    International Nuclear Information System (INIS)

    The Spent Nuclear Fuels Program is in the process of planning activities to remove spent nuclear fuel and other materials from the 100-K Basins as a remediation effort for clean closure. The 105 K- East and K-West Basins store spent fuel, sludge, and debris. Sludge has accumulated in the 1 00 K Basins as a result of fuel oxidation and a slight amount of general debris being deposited, by settling, in the basin water. The ultimate intent in removing the sludge and fuel is to eliminate the environmental risk posed by storing fuel at the K Basins. The task for this project is to disposition specific constituents of sludge (metallic fuel) to produce a product stream through a pretreatment process that will meet the requirements, including a final particle size acceptable to the Tank Waste Remediation System (TWRS). The purpose of this task is to develop a preconceptual design package for the K Basin sludge pretreatment system. The process equipment/system is at a preconceptual stage, as shown in sketch ES-SNF-01 , while a more refined process system and material/energy balances are ongoing (all sketches are shown in Appendix C). Thus, the overall process and 0535 associated equipment have been conservatively selected and sized, respectively, to establish the cost basis and equipment layout as shown in sketches ES- SNF-02 through 08

  14. Environmental sustainability of wastewater sludge treatments

    DEFF Research Database (Denmark)

    Boyer-Souchet, Florence; Larsen, Henrik Fred

    The European Water Framework Directive addresses the issue of pollution from urban waste water and is thereby changing the scope of sewage treatment. As part of this process, the Neptune project (EU, FP6) focuses on developing new and upgrading existing technologies of waste water and sludge...... treatment for municipal waste water. A special focus area in Neptune is sludge handling because the sludge amount is expected to increase due to advanced waste water treatment. The main sludge processing methods assessed in Neptune can be divided into two categories: disintegration processes before...... resources. As part of a sustainability assessment (or “best practice evaluation”), a comparison between the existing and new sludge handling techniques have been done by use of life cycle assessment (LCA).The concept of induced impacts as compared to avoided impacts when introducing a new sludge treatment...

  15. Chemical species of plutonium in Hanford radioactive tank waste

    Energy Technology Data Exchange (ETDEWEB)

    Barney, G.S.

    1997-10-22

    Large quantities of radioactive wastes have been generated at the Hanford Site over its operating life. The wastes with the highest activities are stored underground in 177 large (mostly one million gallon volume) concrete tanks with steel liners. The wastes contain processing chemicals, cladding chemicals, fission products, and actinides that were neutralized to a basic pH before addition to the tanks to prevent corrosion of the steel liners. Because the mission of the Hanford Site was to provide plutonium for defense purposes, the amount of plutonium lost to the wastes was relatively small. The best estimate of the amount of plutonium lost to all the waste tanks is about 500 kg. Given uncertainties in the measurements, some estimates are as high as 1,000 kg (Roetman et al. 1994). The wastes generally consist of (1) a sludge layer generated by precipitation of dissolved metals from aqueous wastes solutions during neutralization with sodium hydroxide, (2) a salt cake layer formed by crystallization of salts after evaporation of the supernate solution, and (3) an aqueous supernate solution that exists as a separate layer or as liquid contained in cavities between sludge or salt cake particles. The identity of chemical species of plutonium in these wastes will allow a better understanding of the behavior of the plutonium during storage in tanks, retrieval of the wastes, and processing of the wastes. Plutonium chemistry in the wastes is important to criticality and environmental concerns, and in processing the wastes for final disposal. Plutonium has been found to exist mainly in the sludge layers of the tanks along with other precipitated metal hydrous oxides. This is expected due to its low solubility in basic aqueous solutions. Tank supernate solutions do not contain high concentrations of plutonium even though some tanks contain high concentrations of complexing agents. The solutions also contain significant concentrations of hydroxide which competes with other

  16. Chemical species of plutonium in Hanford radioactive tank waste

    International Nuclear Information System (INIS)

    Large quantities of radioactive wastes have been generated at the Hanford Site over its operating life. The wastes with the highest activities are stored underground in 177 large (mostly one million gallon volume) concrete tanks with steel liners. The wastes contain processing chemicals, cladding chemicals, fission products, and actinides that were neutralized to a basic pH before addition to the tanks to prevent corrosion of the steel liners. Because the mission of the Hanford Site was to provide plutonium for defense purposes, the amount of plutonium lost to the wastes was relatively small. The best estimate of the amount of plutonium lost to all the waste tanks is about 500 kg. Given uncertainties in the measurements, some estimates are as high as 1,000 kg (Roetman et al. 1994). The wastes generally consist of (1) a sludge layer generated by precipitation of dissolved metals from aqueous wastes solutions during neutralization with sodium hydroxide, (2) a salt cake layer formed by crystallization of salts after evaporation of the supernate solution, and (3) an aqueous supernate solution that exists as a separate layer or as liquid contained in cavities between sludge or salt cake particles. The identity of chemical species of plutonium in these wastes will allow a better understanding of the behavior of the plutonium during storage in tanks, retrieval of the wastes, and processing of the wastes. Plutonium chemistry in the wastes is important to criticality and environmental concerns, and in processing the wastes for final disposal. Plutonium has been found to exist mainly in the sludge layers of the tanks along with other precipitated metal hydrous oxides. This is expected due to its low solubility in basic aqueous solutions. Tank supernate solutions do not contain high concentrations of plutonium even though some tanks contain high concentrations of complexing agents. The solutions also contain significant concentrations of hydroxide which competes with other

  17. Photodegradation of Orange II using waste paper sludge-derived heterogeneous catalyst in the presence of oxalate under ultraviolet light emitting diode irradiation.

    Science.gov (United States)

    Zhou, Guoqiang; Guo, Jinyi; Zhou, Guowang; Wan, Xiankai; Shi, Huixiang

    2016-09-01

    A waste paper sludge-derived heterogeneous catalyst (WPS-Fe-350) was synthesized via a facile method and successfully applied for the degradation of Orange II in the presence of oxalic acid under the illumination of ultraviolet light emitting diode (UV-LED) Powder X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electronic microscopy and N2 sorption isotherm analysis indicated the formation of α-Fe2O3 in the mesoporous nanocomposite. The degradation test showed that WPS-Fe-350 exhibited rapid Orange II (OII) degradation and mineralization in the presence of oxalic acid under the illumination of UV-LED. The effects of pH, oxalic acid concentration and dosage of the catalyst on the degradation of OII were evaluated, respectively. Under the optimal conditions (1g/L catalyst dosage, 2mmol/L oxalic acid and pH3.0), the degradation percentage for a solution containing 30mg/L OII reached 83.4% under illumination by UV-LED for 80min. Moreover, five cyclic tests for OII degradation suggested that WPS-Fe-350 exhibited excellent stability of catalytic activity. Hence, this study provides an alternative environmentally friendly way to reuse waste paper sludge and an effective and economically viable method for degradation of azo dyes and other refractory organic pollutants in water. PMID:27593273

  18. Improved anaerobic digestion of a thermally pretreated mixture of physicochemical sludge; broiler excreta and sugar cane wastes (SCW): Effect on organic matter solubilization, biodegradability and bioenergy production.

    Science.gov (United States)

    Nava-Valente, Noemí; Alvarado-Lassman, Alejandro; Nativitas-Sandoval, Liliana S; Mendez-Contreras, Juan M

    2016-01-01

    Thermal pretreatment effect of a mixture of organic wastes (physicochemical sludge, excreta of broiler chickens and sugarcane wastes (SCW)) in the solubilization and biodegradability organic matter as well as bioenergy production by anaerobic digestion was evaluated. Two different mixtures of physicochemical sludge, excreta of broiler chickens and SCW (70%, 15%, 15% and 60%, 20%, 20% of VS, respectively) were treated at different temperatures (80 °C, 85 °C and 90 °C) and contact time (30, 60 and 90 min). Results indicate that, organic matter solubilization degree increased from 1.14 to 6.56%; subsequently, in the anaerobic digestion process, an increase of 50% in the volatile solids removal and 10% in biogas production was observed, while, retention time decreased from 23 up to 9 days. The results obtained were similar to pilot-scale. In both experimental scales it showed that the synergy produced by the simultaneous anaerobic digestion of different substrates could increase bioenergy production up to 1.3 L bio g(-1) VS removed and 0.82 L CH4 g(-1) VS removed. The treatment conditions presented in this study allow for large residue quantities to be treated and large bioenergy quantities to be produced (10% higher than during conventional treatment) without increasing the anaerobic digester volume. PMID:26819145

  19. Overall strategy and program plan for management of radioactively contaminated liquid wastes and transuranic sludges at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    The use of hydrofracture was terminated after 1984, and LW concentrate has been accumulated and stored since that time. Currently, the volume of stored LW concentrate is near the safe fill limit for the 11 storage tanks in the active LW system, and significant operational constraints are being experienced. The tanks that provide the storage capacity of the active LW system contain significant volumes of TRU sludges that have been designated remote-handled transuranic (RH-TRU) wastes because of associated quantities of other radioisotopes, including 90Sr and 137Cs. Thirty-three additional tanks, which are inactive, also contain significant volumes of TRU waste and radioactive LW. A lack of adequate storage volume for LW jeopardizes ORNL's ability to ensure continued conduct of research and development (RandD) activities that generate LW because an unexpected operational incident could quickly deplete the remaining storage volume. Accordingly, a planning team comprised of staff members from the ORNL Nuclear and Chemical Waste Programs (NCWP) was created for developing recommended actions to be taken for management of LW. A program plan is presented which outlines work required for the development of a disposal method for each of the likely future waste streams associated with LW management and the disposal of the bulk of the resulting solid waste on the ORR. 8 refs., 20 figs., 12 tabs

  20. Mechanical interaction fuel/cladding

    International Nuclear Information System (INIS)

    There is a common agreement that rather large plastic cladding deformation may occur in fast breeder reactor conditions. In thermal irradiation experiments these deformations can be directly measured as cladding diameter increase. In case of fast flux, a distinction must be made between plastic strain and swelling due to pore formation. The separation of these two effects can be made by a combination of cladding diameter measurements and cladding density measurements. A simpler method to determine the mean plastic cladding expansion is to compare the increase of relative mean cladding diameter along the fuel element and the increase of relative cladding length. This comparison for the irradiation experiment in Rapsodie is shown

  1. The use of sewage sludge and horticultural waste to develop artificial soil for plant cultivation in Singapore.

    Science.gov (United States)

    Stabnikova, O; Goh, W-K; Ding, H-B; Tay, J-H; Wang, J-Y

    2005-06-01

    Greenhouse pot experiments were performed with Ipomoea aquatica (Kang Kong) to evaluate artificial soil produced from poor fertility subsoil, horticultural compost, and sewage sludge. The addition of horticultural compost and sewage sludge to subsoil substantially improved plant growth, improved the physical properties of subsoil and enriched subsoil by essential nutrients for plants. The effect was enhanced when the two ingredients were added to subsoil together. The highest yield of biomass of I. aquatica was observed in artificial soil prepared by mixing subsoil with 4% (wet weight/wet weight) of horticultural compost and 2% (dry weight/wet weight) of sewage sludge. The contents of heavy metals in plants, grown in the artificial soil, were significantly lower than toxic levels. The artificial soil could be recommended for urban landscaping and gardening in Singapore. PMID:15668204

  2. Investigation of Rheological Impacts on the Defense Waste Processing Facility's Sludge Slurry Feed as Insoluble Solids and Wash Endpoints are Adjusted

    International Nuclear Information System (INIS)

    The Savannah River Site (SRS) is currently pursuing an aggressive program to empty its High Level Waste (HLW) tanks and immobilize its radioactive waste into a durable borosilicate glass in the Defense Waste Processing Facility (DWPF). To create a batch of feed for the DWPF, several tanks of radioactive sludge slurry are combined into one of the million gallon (i.e. 3.79 E06 liters) feed tanks for DWPF. Once these sludge slurries are combined, the soluble sodium and weight percent total solids are adjusted by a 'washing' process. The 'washing' process involves diluting the soluble sodium of the sludge slurry with inhibited water (0.015 M NaOH and 0.015 M NaNO2) and allowing the sludge slurry to settle into two layers. The two layers in the tank consist of a clear supernate on top and a layer of settled sludge solids on the bottom. The clear supernate layer is then decanted to another hold tank. This 'washing' process is repeated until the desired wash endpoint (i.e. sodium concentration in the supernate) and weight percent total solids are achieved. A final washed batch of feed consists of approximately 500,000 gallons (i.e. 1.89 E06 liters). DWPF has already processed three batches of feed and is currently processing a fourth. Prior to processing a batch of feed in the DWPF, it must be well characterized. Samples of the prepared feed batch are sent to the Savannah River National Laboratory (SRNL) for this characterization. As a part of the SRNL characterization for the fourth batch, rheology measurements were performed. Measurements were performed at different weight percent insoluble solids loadings to mimic potential facility processing scenarios (i.e. mixing/pumping of concentrated sludge slurry). In order to determine the influence of the soluble Na on the rheological properties of the sample, the supernate of the 'as received' sample was adjusted from 1 M soluble Na to 0.5 M soluble Na by using a lab scale version of the 'washing' process. Rheology

  3. Zinc Regime in the Sewage Sludge-Soil-Plant System of a City Waste Water Treatment Pond

    OpenAIRE

    Lacatusu Radu; Lacatusu Anca-Rovena; Lungu Mihaela; Stanciu Burileanu Mihaela Monica; Vrînceanu Andrei

    2014-01-01

    The sewage sludge from wastewater treatment plant of Iasi, a city with 300,000 inhabitants, for domestic and industrial origin, was stored in a mud pond arranged on an area of 18,920 m2. Chemical analyzes of the sludge showed that, of all the chemical elements determined, only Zn is found at pollutant level (5739 mg∙kg-1), i.e. almost 30 times more than the maximum allowable limit for Zn in soil and 45 times more than the Zn content of the soil on which the mud pond has been set. Over time, t...

  4. K Basins sludge removal temporary sludge storage tank system

    International Nuclear Information System (INIS)

    Shipment of sludge from the K Basins to a disposal site is now targeted for August 2000. The current path forward for sludge disposal is shipment to Tank AW-105 in the Tank Waste Remediation System (TWRS). Significant issues of the feasibility of this path exist primarily due to criticality concerns and the presence of polychlorinated biphenyls (PCBS) in the sludge at levels that trigger regulation under the Toxic Substance Control Act. Introduction of PCBs into the TWRS processes could potentially involve significant design and operational impacts to both the Spent Nuclear Fuel and TWRS projects if technical and regulatory issues related to PCB treatment cannot be satisfactorily resolved. Concerns of meeting the TWRS acceptance criteria have evolved such that new storage tanks for the K Basins sludge may be the best option for storage prior to vitrification of the sludge. A recommendation for the final disposition of the sludge is scheduled for June 30, 1997. To support this decision process, this project was developed. This project provides a preconceptual design package including preconceptual designs and cost estimates for the temporary sludge storage tanks. Development of cost estimates for the design and construction of sludge storage systems is required to help evaluate a recommendation for the final disposition of the K Basin sludge

  5. K Basins sludge removal temporary sludge storage tank system

    Energy Technology Data Exchange (ETDEWEB)

    Mclean, M.A.

    1997-06-12

    Shipment of sludge from the K Basins to a disposal site is now targeted for August 2000. The current path forward for sludge disposal is shipment to Tank AW-105 in the Tank Waste Remediation System (TWRS). Significant issues of the feasibility of this path exist primarily due to criticality concerns and the presence of polychlorinated biphenyls (PCBS) in the sludge at levels that trigger regulation under the Toxic Substance Control Act. Introduction of PCBs into the TWRS processes could potentially involve significant design and operational impacts to both the Spent Nuclear Fuel and TWRS projects if technical and regulatory issues related to PCB treatment cannot be satisfactorily resolved. Concerns of meeting the TWRS acceptance criteria have evolved such that new storage tanks for the K Basins sludge may be the best option for storage prior to vitrification of the sludge. A reconunendation for the final disposition of the sludge is scheduled for June 30, 1997. To support this decision process, this project was developed. This project provides a preconceptual design package including preconceptual designs and cost estimates for the temporary sludge storage tanks. Development of cost estimates for the design and construction of sludge storage systems is required to help evaluate a recommendation for the final disposition of the K Basin sludge.

  6. Microbial release of 226Ra2+ from (Ba,Ra)SO4 sludges from uranium mine wastes

    International Nuclear Information System (INIS)

    226Ra2+ is removed from uranium mine effluents by coprecipitation with BaSO4. (Ba,Ra)SO4 sludge samples from two Canadian mine sites were found to contain active heterotrophic populations of aerobic, anaerobic, denitrifying, and sulfate-reducing bacteria. Under laboratory conditions, sulfate reduction occurred in batch cultures when carbon sources such as acetate, glucose, glycollate, lactate, or pyruvate were added to samples of (Ba,Ra)SO4 sludge. No external sources of nitrogen or phosphate were required for this activity. Further studies with lactate supplementation showed that once the soluble SO4(2-) in the overlying water was depleted, Ba2+ and 226Ra2+ were dissolved from the (Ba,Ra)SO4 sludge, with the concurrent production of S2-. Levels of dissolved 226Ra2+ reached approximately 400 Bq/liter after 10 weeks of incubation. Results suggest that the ultimate disposal of these sludges must maintain conditions to minimize the activity of the indigenous sulfate-reducing bacteria to ensure that unacceptably high levels of 226Ra2+ are not released to the environment

  7. Zinc Regime in the Sewage Sludge-Soil-Plant System of a City Waste Water Treatment Pond

    Directory of Open Access Journals (Sweden)

    Lacatusu Radu

    2014-10-01

    Full Text Available The sewage sludge from wastewater treatment plant of Iasi, a city with 300,000 inhabitants, for domestic and industrial origin, was stored in a mud pond arranged on an area of 18,920 m2. Chemical analyzes of the sludge showed that, of all the chemical elements determined, only Zn is found at pollutant level (5739 mg∙kg-1, i.e. almost 30 times more than the maximum allowable limit for Zn in soil and 45 times more than the Zn content of the soil on which the mud pond has been set. Over time, the content of Zn in the mud pond, but also from soil to which it has been placed, has become upper the normal content of the surrounding soil up to a depth of 260 cm. On the other hand, the vegetation installed on sewage sludge in the process of mineralization, composed predominantly of Phragmites, Rumex, Chenopodium, and Aster species had accumulated in roots, stems and leaves Zn quantities equivalent to 1463 mg Kg-1, 3988 mg Kg-1, 1463 mg Kg-1, respectively, 1120 mg∙Kg-1. The plants in question represents the natural means of phytoremediation, and sewage sludge as such may constitute a fertilizer material for soils in the area, on which Zn deficiency in maize has been recorded. In addition, the ash resulted from the incineration of plants loaded with zinc may constitute, in its turn, a good material for fertilizing of the soils that are deficient in zinc.

  8. Biodegradation of chlorpyrifos by Klebsiella sp. isolated from an activated sludge sample of waste water treatment plant in Damascus.

    Science.gov (United States)

    Ghanem, I; Orfi, M; Shamma, M

    2007-01-01

    A chlorpyrifos (CPY)-degrading bacterial strain was isolated from an activated sludge sample collected from the Damascus Wastewater Treatment Plant, Syria. The isolation of Klebsiella sp. was facilitated by the addition of CPY at a rate of 3.84 g/L of sludge weekly (selection pressure). Identification of Klebsiella sp. was done using major staining and biochemical differentiation tests (Gram stain, cytochrome oxidase and some relevant saccharide fermentation tests using biochemical assays). Klebsiella sp. was maintained by culturing in a poor medium consisting of mineral salts and CPY as the sole carbon source. When 3 activated sludge samples were incubated in the presence of CPY (13.9 g/L sludge), 46% of added CPY were degraded within 4 d. By comparison, within 4 d the isolated Klebsiella sp. was found to break down 92% of CPY when co-incubated in a poor mineral medium in which CPY was the sole carbon source (13.9 g/L poor medium). Isolated Klebsiella sp. was able to tolerate up to 17.3 g of CPY in the poor medium. PMID:18062192

  9. Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge

    International Nuclear Information System (INIS)

    Highlights: • Two strategies to reduce PCDD/F formation when co-firing solid recovered fuel (SRF) and biomass. • They were co-combustion with municipal sewage sludge (MSS) and addition of ammonium sulphate. • PCDD/Fs were significantly reduced for a biomass rich in chlorine when adding ammonium sulphate. • MSS had a suppressing effect on PCDD/F formation during co-combustion with SRF. • A link is presented between gaseous alkali chlorides, chlorine in deposits and PCDD/F formation. - Abstract: Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (th circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel

  10. PCDD/F in sewage sludges from two waste water treatment facilities in Rio de Janeiro State, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Souza Pereira, M. de [Universidade Federal Fluminense, Niteroi (Brazil). Dept. de Geoquimica - Instituto de Quimica; Kuch, B. [Stuttgart Univ. (Germany). Inst. fuer Siedlungswasserbau, Wasserguete- und Abfallwirtschaft, Abt. Hydrochemie, Fakultaet fuer Bauingenieur- und Vermessungswesen

    2004-09-15

    In Brazil, up to now, there is no specific legislation regarding the maximum equivalent concentration levels of organochlorine compounds in especial polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) in sewage sludge/biocompost considered for agricultural use or final deposition in soils. Besides the great risk heavy metals pose to humans and environment, PCDD/PCDF are types of persistent environmental contaminants with enhanced toxicity and carcinogenic and bioaccumulating properties. To PCDD/F, the human exposure is primarily attributed to background contamination caused by diffuse contamination of these pollutants coming from different sources and subsequently biomagnification through the trophic chain. As alternative paths of the diffuse contamination with PCDD/F, the transport of these substances by air deposition, by residual waters from household, industrial processes as well as by laundry of products treated with contaminated chemicals and the microbial activity on chlorophenols are listed. Possible transference pathways of these compounds to humans would be both the uptake via contaminated crops and grazing livestock, coming from sludge-amended soils 11. Concerning PCDD/F, a tolerable daily intake (TDI) of 1-4 pg I-TEQ/kg/day is recommended, according to the WHO/EURO standard guidelines, which would be exceeded if a persons diet came solely from land treated with sewage sludge containing high concentrations of PCDD/F. This work shows the results of a first study about the heavy metal, PCDD/PCDF content of sewage sludge coming from both an urban and a semi-agricultural area in the State of Rio de Janeiro, Brazil in comparison to results found in the region of Baden-Wuerttenberg, south Germany. The potential toxicity and probably sources related to these contaminants in Brazilian sewage sludge was also investigated.

  11. Combined Effect of Free Nitrous Acid Pretreatment and Sodium Dodecylbenzene Sulfonate on Short-Chain Fatty Acid Production from Waste Activated Sludge

    OpenAIRE

    Jianwei Zhao; Yiwen Liu; Bingjie Ni; Qilin Wang; Dongbo Wang; Qi Yang; Yingjie Sun; Guangming Zeng; Xiaoming Li

    2016-01-01

    Free nitrous acid (FNA) serving as a pretreatment is an effective approach to accelerate sludge disintegration. Also, sodium dodecylbenzene sulfonate (SDBS), a type of surfactants, has been determined at significant levels in sewage sludge, which thereby affects the characteristics of sludge. Both FNA pretreatment and sludge SDBS levels can affect short-chain fatty acid (SCFA) generation from sludge anaerobic fermentation. To date, however, the combined effect of FNA pretreatment and SDBS pre...

  12. The characteristics of organic sludge/sawdust derived fuel.

    Science.gov (United States)

    Chen, Wei-Sheng; Chang, Fang-Chih; Shen, Yun-Hwei; Tsai, Min-Shing

    2011-05-01

    A fundamental study of the characteristics of a sludge refuse-derived fuel (RDF) and the combustion behaviors were done. The test data demonstrate good results for the development of energy recovery technology of organic sludge or waste. The ash deposit formation propensity has been based on pretreatment, temperature and the ratio of organic sludge to sawdust. The usage of organic sludge and waste as an alternative fuel is cost effective and has environmental benefits. PMID:21129953

  13. Sludge reduction by lumbriculus variegatus in Ahvas wastewater treatment plant

    OpenAIRE

    Basim Yalda; Farzadkia Mahdi; Jaafarzadeh Nematollah; Hendrickx Tim

    2012-01-01

    Abstract Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahva...

  14. Sludge derived fuel technique of sewage sludge by oil vacuum evaporation drying

    International Nuclear Information System (INIS)

    Sewage sludge contains high content of organic materials and its water content is also very high about 80% even after filtration process. Landfill as a sludge treatment methods can cause odor problem and leachate production which can derive the secondary contamination of soil and groundwater. The ocean dumping will be prohibited according to the London Convention and domestic stringent environmental regulation. Based on domestic agenda on organic sewage sludge treatment, the ocean disposal will be prohibited from 2012, thus alternative methods are demanded. Sludge derived fuel (SDF) technology can alleviate the emission of greenhouse gas and recover energy from sludge. For proper treatment and SDF production from sludge, the vacuum evaporation and immersion frying technology was adopted in this research. This technology dries moisture in sludge after mixing with oil such as Bunker C oil, waste oil or waste food oil etc. Mixing sludge and oil secures liquidity of organic sludge to facilitate handling throughout the drying process. The boiling temperature could be maintained low through vacuum condition in whole evaporation process. This study was performed to find the optimum operating temperature and pressure, the mixing ratio of sludge and oil. Finally, we could obtained SDF which moisture content was less than 5%, its heating value was over 4,500 kcal/ kg sludge. This heating value could satisfy the Korean Fuel Standard for the Recycle Products. Assessed from the perspective of energy balance and economic evaluation, this sludge drying system could be widely used for the effective sludge treatment and the production of SDF. (author)

  15. An efficient and green pretreatment to stimulate short-chain fatty acids production from waste activated sludge anaerobic fermentation using free nitrous acid.

    Science.gov (United States)

    Li, Xiaoming; Zhao, Jianwei; Wang, Dongbo; Yang, Qi; Xu, Qiuxiang; Deng, Yongchao; Yang, Weiqiang; Zeng, Guangming

    2016-02-01

    Short-chain fatty acid (SCFA) production from waste activated sludge (WAS) anaerobic fermentation is often limited by the slow hydrolysis rate and poor substrate availability, thus a long fermentation time is required. This paper reports a new pretreatment approach, i.e., using free nitrous acid (FNA) to pretreat sludge, for significantly enhanced SCFA production. Experimental results showed the highest SCFA production occurred at 1.8 mg FNA/L with time of day 6, which was 3.7-fold of the blank at fermentation time of day 12. Mechanism studies revealed that FNA pretreatment accelerated disruption of both extracellular polymeric substances and cell envelope. It was also found that FNA pretreatment benefited hydrolysis and acidification processes but inhibited the activities of methanogens, thereby promoting the yield of SCFA. In addition, the FNA pretreatment substantially stimulated the activities of key enzymes responsible for hydrolysis and acidification, which were consistent with the improvement of solubilization, hydrolysis and acidification of WAS anaerobic fermentation. PMID:26363316

  16. Co-digestion of press liquids of source-sorted municipal organic waste in anaerobic sludge treatment of municipal wastewater treatment plants.

    Science.gov (United States)

    Effenberger, Johannes; Jahn, Lydia; Kuehn, Volker

    2016-01-01

    This paper describes a semi-continuous laboratory-scale investigation of a potential co-substrate for mesophilic anaerobic sludge digestion in a municipal wastewater treatment plant. A feed liquid produced from source-sorted municipal organic waste by pretreatment with a screw press was subjected to the investigation. Quantities produced in press trials as well as the composition of the feed liquid are presented. Mass balances for N, P and chemical oxygen demand are given in order to verify the methane production of the feed liquid in co-digestion with sewage sludge at mesophilic conditions. Hydraulic retention time of the reactors were 14.7 to 16 d and organic loading rates were 1.5 to 2.7 kg volatile solids (VS) per cubic metre per day. The pretreatment by screw press is compared to the production of feed liquids with pulper-based pretreatment processes. While the addition of the feed liquid increased methane production by about 345 ml CH(4)/g VS(in), total solids of the feed liquid were reduced to about 63%. With respect to co-digestion at municipal wastewater treatment plants, several risks associated with the investigated feed liquid are outlined. PMID:27332856

  17. Distribution of tetracycline resistance genes in anaerobic treatment of waste sludge: The role of pH in regulating tetracycline resistant bacteria and horizontal gene transfer.

    Science.gov (United States)

    Huang, Haining; Chen, Yinguang; Zheng, Xiong; Su, Yinglong; Wan, Rui; Yang, Shouye

    2016-10-01

    Although pH value has been widely regarded as an important factor that affects resource recovery of waste sludge, the potential influence of diverse pHs on the distribution of tetracycline resistance genes (TRGs) during sludge anaerobic treatment is largely unknown. Here we reported that in the range of pH 4-10, 0.58-1.18 log unit increase of target TRGs was observed at pH 4, compared with that at pH 7, while 0.70-1.31 log unit further removal were obtained at pH 10. Mechanism study revealed that varied pHs not only altered the community structures of tetracycline resistant bacteria (TRB), but also changed their relative abundances, benefitting the propagation (acidic pHs) or attenuation (alkaline pHs) of TRB. Further investigation indicated that the amount and gene-possessing abilities of key genetic vectors for horizontal TRGs transfer were greatly promoted at acidic pHs but restricted under alkaline conditions. PMID:27485281

  18. Vitrification and Product Testing of C-104 and AZ-102 Pretreated Sludge Mixed with Flowsheet Quantities of Secondary Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Gary L.; Bates, Derrick J.; Goles, Ronald W.; Greenwood, Lawrence R.; Lettau, Ralph C.; Piepel, Gregory F.; Schweiger, Michael J.; Smith, Harry D.; Urie, Michael W.; Wagner, Jerome J.

    2001-02-01

    The U.S. Department of Energy (DOE) Office of River Protection (ORP) has acquired Hanford tank waste treatment services at a demonstration scale. The River Protection Project Waste Treatment Plant (RPP-WTP) team is responsible for producing an immobilized (vitrified) high-level waste (IHLW) waste form. Pacific Northwest National Laboratory, hereafter referred to as PNNL, has been contracted to produce and test a vitrified IHLW waste form from two Envelope D high-level waste (HLW) samples previously supplied to the RPP-WTP project by DOE.

  19. Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Åmand, Lars-Erik [Chalmers University of Technology, Department of Energy and Environment, Gothenburg (Sweden); Kassman, Håkan, E-mail: hakan.kassman@vattenfall.com [Vattenfall Research and Development AB, Nyköping (Sweden)

    2013-08-15

    Highlights: • Two strategies to reduce PCDD/F formation when co-firing solid recovered fuel (SRF) and biomass. • They were co-combustion with municipal sewage sludge (MSS) and addition of ammonium sulphate. • PCDD/Fs were significantly reduced for a biomass rich in chlorine when adding ammonium sulphate. • MSS had a suppressing effect on PCDD/F formation during co-combustion with SRF. • A link is presented between gaseous alkali chlorides, chlorine in deposits and PCDD/F formation. - Abstract: Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW{sub th} circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS

  20. Trace metal determination by total-reflection x-ray fluorescence (TXRF) for the differentiation between pure fuel oil (bunker oil) and waste oil (sludge) in maritime shipping legal cases

    International Nuclear Information System (INIS)

    Using a simple sample preparation technique, the concentrations of Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Pb in several bunker and sludge oils have been measured simultaneously by total-reflection X-ray fluorescence analysis (TXRF) in the mg/kg range. As a result, five elements are suitable in distinguishing between both types of oil: Ca, V, Fe, Ni and Zn. This differentiation can be used in cases where shipping vessel captains or chiefs attempt to conceal illegal waste oil discharge at sea by wrongly declaring bunker oil as sludge. (author)