WorldWideScience

Sample records for acid tar sludges

  1. Utilization of acid tars

    Frolov, A.F.; Denisova, T.L.; Aminov, A.N.

    1987-01-01

    Freshly produced acid tar (FPAT), obtained as refinery waste in treating petroleum oils with sulfuric acid and oleum, contains 80% or more sulfuric acid. Of such tars, pond acid tars, which contain up to 80% neutral petroleum products and sulfonated resins, are more stable, and have found applications in the production of binders for paving materials. In this article the authors are presenting results obtained in a study of the composition and reactivity of FPAT and its stability in storage in blends with asphalts obtained in deasphalting operations, and the possibility of using the FPAT in road construction has been examined. In this work, wastes were used which were obtained in treating the oils T-750, KhF-12, I-8A, and MS-14. Data on the change in group chemical composition of FPAT are shown, and the acidity, viscosity, needle penetration, and softening point of acid tars obtained from different grades of oils are plotted as functions of the storage time. It is also shown that the fresh and hardened FPATs differ in their solubilities in various solvents.

  2. Characterization of acid tars

    Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

  3. Sewage sludge gasification characteristics and tar reduction using catalysts

    This study tested various types of catalysts such as dolomite steel slag and quicklime for tar reduction in the sewage sludge gasification process. For the experiments of sewage sludge gasification reaction characteristics and tar reduction using the catalysts a fixed bed of lab scale experimental apparatus was set up. The reactor was made of quartz glass using electric muffle furnaces. The sewage sludge samples were used with moisture content less than 6%. The catalysts were prepared using Dolomite (Seongshin Inc.) Steel slag (Hyundai Steel Co. Ltd.) Quicklime (Tae young EMC Co. LTD.). The experimental conditions were as follows sample weight was 20 g and reaction time was 10 minutes gasification reaction temperature was from 600 degree Celsius to 800 degree Celsius and the equivalence ratio was 0.2. Mass of catalysts were 2 g, 4 g, 6 g and temperatures of catalyst layer were 500 to 700 degree Celsius. The gas was analyzed for yield composition of product gas by GC/TCD(carbogen 1000 column) and tar composition of product gas by GC-mass(HP-Plan Al2O3/ KCl column). As reaction temperature increased up 800 degree Celsius yields of gaseous products and liquid products increased while char and tar products decreased which had effect on gas product compositions. These results were considered due to the increase of water gas reaction and Boudouard reaction. In the case of experiments with catalyst mass of catalysts were determined dolomite (4 g) steel slag (6 g) and quicklime (6 g) by previous experiments. When temperature of catalyst increased, weight of tar produced decreased with different cracking performance by catalysts. Reforming reaction on the surface of dolomite steel slag CaO of quicklime occurred caused by cracking of hydrocarbon structure. (author)

  4. Composition and properties of acid tar and asphalt produced from acid tar

    Frolov, A.F.; Aminov, A.N.; Timrot, S.D.

    Acid tar is a waste material that is produced in large volumes in treating petroleum oils with concentrated sulfuric acid. The acid tar contains up to 80% petroleum oils and tars and resins. In current practice, the acid tar is dumped into holding ponds that take up large areas of land; this practice leads to pollution of the ground, water, and air. The amounts of acid tar available in holding ponds are such that it can be used as raw material for the production of paving asphalt. This paper presents results from an investigation of the group composition and rheological properties of acid tar and the BKG asphalt produced from this tar. The fresh acid tar contains from 25 to 60% sulfuric acid. The group composition of the organic part of the fresh acid tar, as determined by the method of Sereda varies over wide limits, depending on the type of crude and the oils being produced (transformer, motor, perfumery, cylinder, etc.(: 34-94% resin/oil and resin/asphaltene substances, 5-60% sulfonic acids, and 1-6% carboxylic acids. Experimental results are plotted, tabulated and discussed in terms of recommendation for practical uses. 10 refs.

  5. Implementation of an ex situ stabilization technique at the Sand Springs superfund site to solidify and stabilize acid tar sludges involving a quick-lime based stabilization process and innovative equipment design

    McManus, R.W. [SOUND Environmental Services, Inc., Dallas, TX (United States); Grajczak, P. [ARCO, Los Angeles, CA (United States); Wilcoxson, J.C. [ARCO, Plano, TX (United States); Webster, S.D. [Environmental Protection Agency, Dallas, TX (United States)

    1997-12-31

    An old refinery site was safely remediated a year before schedule and for 25% less than final engineering estimates for the stabilization remedy thanks to energetic project management and innovative design involving ex situ stabilization/solidification of acid tar sludges. A quicklime based process, Dispersion by Chemical Reaction (DCR{trademark}), was employed to solidify and stabilize (SS) over 103,000 cubic meters (135,000 cubic yards) of petroleum waste, mostly acidic tarry sludge. The SS process was selected over competing methods because it afforded minimal volume increase, could readily achieve Record of Decision (ROD) specified physical and chemical treatment goals, could be implemented with treatment equipment that minimized emissions, and could be performed with low reagent usage and at low cost. To ensure treatment goals were achieved and an accelerated schedule met, a custom designed and fabricated transportable treatment unit (TTU) was employed to implement the process. The treated material was visually soil-like in character, it was left in stockpiles for periods of time, and it was placed and compacted in the on site landfill using standard earth-moving equipment.

  6. Remediation of mixed acidic tar and dredged bay mud

    Refineries using sulfuric acid in the production of lubricating oils produce a sulfonated byproduct, acid sludge tar. The acid sludge tar was typically hauled to an impoundment. In certain jurisdictions, regulatory pressures are being exerted to remediate impoundment contents. This paper will present a case history of the remediation of the contents of such an impoundment. The remediation involved the excavation, neutralization, stabilization. and replacement of more than 150,000 cubic yards of hazardous waste contained in an on-site impoundment at one California Refinery. The site was remediated under strict oversight by several regulatory agencies and two environmental consulting firms. A significant bench-scale testing program was initiated before the project began, and several full-scale tests were performed to optimize the treatment and stabilization process. During processing of the 150,000 cubic yards of waste, comprehensive performance specifications including leachability, strength, stiffness, compaction, and aquatic toxicity testing of the processed waste material were satisfied. An extensive quality control program was in place to ensure the product met the performance specifications

  7. Effect of wastewater treatment processes on the pyrolysis properties of the pyrolysis tars from sewage sludges

    Wu, Xia; Xie, Li-Ping; Li, Xin-Yu; Dai, Xiao-Hong; Fei, Xue-Ning; Jiang, Yuan-Guang

    2011-06-01

    The pyrolysis properties of five different pyrolysis tars, which the tars from 1# to 5# are obtained by pyrolyzing the sewage sludges of anaerobic digestion and indigestion from the A2/O wastewater treatment process, those from the activated sludge process and the indigested sludge from the continuous SBR process respectively, were studied by thermal gravimetric analysis at a heating rate of 10 °C/min in the nitrogen atmosphere. The results show that the pyrolysis processes of the pyrolysis tars of 1#, 2#, 3# and 5# all can be divided into four stages: the stages of light organic compounds releasing, heavy polar organic compounds decomposition, heavy organic compounds decomposition and the residual organic compounds decomposition. However, the process of 4# pyrolysis tar is only divided into three stages: the stages of light organic compounds releasing, decomposition of heavy polar organic compounds and the residual heavy organic compounds respectively. Both the sludge anaerobic digestion and the "anaerobic" process in wastewater treatment processes make the content of light organic compounds in tars decrease, but make that of heavy organic compounds with complex structure increase. Besides, both make the pyrolysis properties of the tars become worse. The pyrolysis reaction mechanisms of the five pyrolysis tars have been studied with Coats-Redfern equation. It shows that there are the same mechanism functions in the first stage for the five tars and in the second and third stage for the tars of 1#, 2#, 3# and 5#, which is different with the function in the second stage for 4# tar. The five tars are easy to volatile.

  8. Sedimentation of sulfuric acid in acid tars from current production

    Denisova, T.L.; Frolov, A.F.; Aminov, A.N.; Novosel' tsev, S.P.

    1987-09-01

    Acid tars obtained in treating T-750, KhF-12, and I-8A oils were investigated for purposes of recovering sulfuric acid and asphalt binders from the compositions and of determining the effects of storage time on the recovery. The consumption and sedimentation levels of sulfuric acid during storage for different periods and at different temperatures were assessed. The characteristics of an asphalt binder obtained by neutralizing acid tar with a paste consisting of asphalts from deasphalting operations and slaked lime, followed by oxidation of the mixture with atmospheric air, were determined. The sulfuric acid recovered in the settling process could be burned in order to purify it of organic contaminants.

  9. Composition of acid tars from sulfuric acid treatment of petroleum oils

    Frolov, A.F.; Denisova, T.L.; Karpova, I.V.; Titova, T.S.

    1986-01-01

    This paper examines the composition of freshly produced acid tars and pond tars, gives an analysis of the acid part of the tars, and obtains data on the change in composition of the acid tar in the course of storage--data that are needed in developing methods for utilizing the tar. The acid-pond tars consist of a mixture of hydrocarbons with a very low content of acids, whereas the freshly produced acid tars consist mainly of sulfuric acid, sulfonic acids, and carboxylic acids. In the course of storage, hardening of acid tars in the volume proceeds through reactions of polymerization, condensation, and oxidation of the surface layer that is in contact with air.

  10. The characterisation of tars produced during the gasification of sewage sludge in a spouted bed reactor

    A. Adegoroye; N. Paterson; X. Li; T. Morgan; A.A. Herod; D.R. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Chemical Engineering

    2004-10-01

    Tars released by the gasification of sewage sludge in a spouted bed gasifier have been collected, quantified and characterised. The amounts collected were low which shows that the volatiles contained in the feedstock were cracked efficiently under the conditions in the gasifier. The presence of a high concentration of steam in the gasifying medium enhanced the conversion further. Within the 760-980{sup o}C range, the amount present did not show any variation with temperature of formation. GC/MS of a limited number of samples showed that the tars it had an aromatic character, as expected at the temperatures used. Approximately, 60-70% of the tars evaporated below 450{sup o}C. Thermogravimetric analysis of the tar-trap samples has allowed an estimation of the boiling point distributions of the samples. For the majority of the tar samples, from both types of sewage, between 60 and 70% of the tar boiled at {lt} 450{sup o}C. The Biogran tar exhibited a trend of an increase in the {lt} 250{sup o}C fraction and an increase in the {gt} 450{sup o}C fraction, with increasing temperature of formation. The Danish tar-trap samples showed a decreasing trend in both fractions with increasing temperature. These data give an indication of the way the tars progressively break down under the gasifier conditions and implies that steam can have an impact on the reaction pathway. Changes in the composition of the tars with temperature were also identified using size exclusion chromatography (SEC) and by ultra violet fluorescence spectroscopy (UV-F). 21 refs., 11 figs., 9 tabs.

  11. Receiving demulsifying agent from the acid tar

    Nikitina, A.A.; Belyaeva, A.S.; Kunakova, R.V. [FGBIHE ' Ufa State Academy of Economics and Services' , Ufa (Russian Federation); Movsumzade, E.M. [FGBIHE ' Ufa State Petroleum Technological Univ.' , Ufa (Russian Federation); Lapidus, A.L. [Russian Academy of Sciences, Moscow (Russian Federation). N.D. Zelinsky Institute of Organic Chemistry

    2012-07-01

    The processing of wastes of petrochemical production makes it possible to reduce the price of produced commodity of petroleum products substantially. Bitumen, fuel oils, tars and other mixture of heavy organic compounds are widely used in road construction, in paint and cable industries, manufacture of roofing materials, are used as boiler and furnace fuel, fuel for marine diesel engines, raw material for the production of modifying additives, fillers, surfaceactive substances, etc. (orig.)

  12. Thermal degradation of cold cured anthracite/coke breeze briquettes prepared from a coal tar acid resin

    Thoms, L.J.; Snape, C.E.; Taylor, D.; Mullens, J.; Mullens, S. [University of Strathclyde, Glasgow (United Kingdom). Department of Pure & Applied Chemistry

    1999-07-01

    Phenolic resoles were synthesised using a coal tar acid fraction of the oil from a low temperature carbonisation process. Anthracite/coke breeze briquettes were prepared using the tar acid resoles. Thermogravimetric analysis-mass spectrometry of products and combustion of briquettes are described. 4 refs., 1 tab.

  13. Chemical stability of acid rock drainage treatment sludge and implications for sludge management.

    McDonald, Danny M; Webb, John A; Taylor, Jeff

    2006-03-15

    To assess the chemical stability of sludges generated by neutralizing acid rock drainage (ARD) with alkaline reagents, synthetic ARD was treated with hydrated lime (batch and high-density sludge process), limestone, and two proprietary reagents (KB-1 and Bauxsol). The amorphous metal hydroxide sludge produced was leached using deionized water, U.S. EPA methods (toxicity characteristic leaching procedure, synthetic precipitation leaching procedure), and the new strong acid leach test (SALT), which leaches the sludge with a series of sulfuric acid extractant solutions; the pH decreases by approximately 1 pH unit with each test, until the final pH is approximately 2. Sludges precipitated by all reagents had very similar leachabilities except for KB-1 and Bauxsol, which released more aluminum. SALT showed that lowering the pH of the leaching solution mobilized more metals from the sludges. Iron, aluminum, copper, and zinc began to leach at pH 2.5-3, approximately 4.5, approximately 5.5, and 6-6.5, respectively. The leachability of ARD treatment sludges is determined by the final pH of the leachate. A higher neutralization potential (e.g., a greater content of unreacted neutralizing agent) makes sludges inherently more chemically stable. Thus, when ARD or any acidic metalliferous wastewater is treated, a choice must be made between efficient reagent use and resistance to acid attack. PMID:16570625

  14. Suspended biofilm carrier and activated sludge removal of acidic pharmaceuticals

    Falås, Per; Baillon-Dhumez, Aude; Andersen, Henrik Rasmus;

    2012-01-01

    Removal of seven active pharmaceutical substances (ibuprofen, ketoprofen, naproxen, diclofenac, clofibric acid, mefenamic acid, and gemfibrozil) was assessed by batch experiments, with suspended biofilm carriers and activated sludge from several full-scale wastewater treatment plants. A distinct...... difference between nitrifying activated sludge and suspended biofilm carrier removal of several pharmaceuticals was demonstrated. Biofilm carriers from full-scale nitrifying wastewater treatment plants, demonstrated considerably higher removal rates per unit biomass (i.e. suspended solids for the sludges and...... attached solids for the carriers) of diclofenac, ketoprofen, gemfibrozil, clofibric acid and mefenamic acid compared to the sludges. Among the target pharmaceuticals, only ibuprofen and naproxen showed similar removal rates per unit biomass for the sludges and biofilm carriers. In contrast to...

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

    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.

  16. ALUMINUM RECLAMATION BY ACIDIC EXTRACTION OF ALUMINUM-ANODIZING SLUDGES

    Extraction of aluminum-anodizing sludges with sulfuric acid was examined to determine the potential for production of commercial-strength solutions of aluminum sulfate, that is liquid alum. The research established kinetic and stoichiometric relationships and evaluates product qu...

  17. GLYCOLIC-FORMIC ACID FLOWSHEET SLUDGE MATRIX STUDY

    Lambert, D.; Koopman, D.

    2011-06-30

    Testing was completed to demonstrate the viability of the newly developed glycolic acid/formic acid flowsheet on processing in the Defense Waste Processing Facility's (DWPF) Chemical Process Cell (CPC). The Savannah River National Laboratory (SRNL) initiated a sludge matrix study to evaluate the impact of changing insoluble solid composition on the processing characteristics of slurries in DWPF. Four sludge simulants were prepared to cover two compositional ranges in the waste. The first was high iron/low aluminum versus low iron/high aluminum (referred to as HiFe or LoFe in this report). The second was high calcium-manganese/low nickel, chromium, and magnesium versus low calcium-manganese/high nickel, chromium, and magnesium (referred to as HiMn or LoMn in this report). These two options can be combined to form four distinct sludge compositions. The sludge matrix study called for testing each of these four simulants near the minimum acid required for nitrite destruction (100% acid stoichiometry) and at a second acid level that produced significant hydrogen by noble metal catalyzed decomposition of formic acid (150% acid stoichiometry). Four simulants were prepared based on the four possible combinations of the Al/Fe and Mn-Ca/Mg-Ni-Cr options. Preliminary simulant preparation work has already been documented. The four simulants were used for high and low acid testing. Eight planned experiments (GF26 to GF33) were completed to demonstrate the viability of the glycolic-formic flowsheet. Composition and physical property measurements were made on the SRAT product. Composition measurements were made on the condensate from the Mercury Water Wash Tank (MWWT), Formic Acid Vent Condenser (FAVC), ammonia scrubber and on SRAT samples pulled throughout the SRAT cycle. Updated values for formate loss and nitrite-tonitrate conversion were found that can be used in the acid calculations for future sludge matrix process simulations with the glycolic acid/formic acid

  18. Physical characteristics of cold cured anthracite/coke breeze briquettes prepared from a coal tar acid resin

    Thoms, L.J.; Snape, C.E.; Taylor, D. [University of Strathclyde, Glasgow (United Kingdom). Dept. of Pure and Applied Chemistry

    1999-11-01

    Phenolic resins were synthesised using the whole coal tar acid fraction of the oil from a low temperature carbonisation process. A series of briquettes were prepared using a number of coal tar acid concentrations, cured at ambient temperature with various concentrations of sulphuric acid and were subjected to a variety of physical tests. Excellent briquettes, in terms of mechanical strength, water-proofing characteristics and thermal degradation, were produced with both nominally 10 and 9% w/w resole solution and acid concentrations down to 1.8 M, corresponding to sulphur addition in the briquettes of ca. 0.2% w/w. Briquettes bound with 8% w/w resole solution, however, required stronger acid concentrations to satisfy the test conditions. When the briquettes were combusted up to 850{degree}C, they retained their core shape after 70% weight loss. 16 refs., 4 figs., 4 tabs.

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

    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

  20. K Basin Sludge Conditioning Testing: Nitric Acid Dissolution Testing of K East Canister Sludge

    This report describes tests performed by Pacific Northwest National Laboratory (PNNL) for Numatec Hanford Corporation (NHC) as part of the overall activities for the development of the K Basin Sludge Treatment System. These tests were conducted to examine the dissolution behavior of a K East Basin canister sludge composite in nitric acid at the following concentrations: 2 M, 4 M, 6 M, 7.8 M and 10 M and temperatures of 25 C and boiling. Assuming that the sludge was 100% uranium metal, a 4X stoichiometric excess of nitric acid was used for all testing, except that conducted at 4 M. In the 4 M nitric acid dissolution test, 50% excess nitric acid was used resulting in a dissolver solution with a significantly higher solids loading. The boiling tests were conducted for 11 hr, the 25 C dissolution tests were conducted from 24 hr to 2 weeks. For the 25 C dissolution testing, the weight percent residual solids was determined, however, chemical and radiochemical analyses were not performed

  1. A Tat-grafted anti-nucleic acid antibody acquires nuclear-localization property and a preference for TAR RNA

    Highlights: → We generate 'H3Tat-3D8' by grafting Tat48-60 peptide to VH CDR of 3D8 scFv antibody. → H3Tat-3D8 antibody retains nucleic acid binding and hydrolyzing activities. → H3Tat-3D8 acquires a preference for TAR RNA structure. → Properties of Tat48-60 is transferred to an antibody via Tat-grafting into a CDR. -- Abstract: The 3D8 single chain variable fragment (3D8 scFv) is an anti-nucleic acid antibody that can hydrolyze nucleic acids and enter the cytosol of cells without reaching the nucleus. The Tat peptide, derived from the basic region of the HIV-1 Tat protein, translocates to cell nuclei and has TAR RNA binding activity. In this study, we generated a Tat-grafted antibody (H3Tat-3D8) by replacing complementarity-determining region 3 (CDR3) within the VH domain of the 3D8 scFv with a Tat48-60 peptide (GRKKRRQRRRPPQ). H3Tat-3D8 retained the DNA-binding and DNA-hydrolyzing activity of the scFv, and translocated to the nuclei of HeLa cells and preferentially recognized TAR RNA. Thus, the properties associated with the Tat peptide were transferred to the antibody via Tat-grafting without loss of the intrinsic DNA-binding and hydrolyzing activities of the 3D8 scFv antibody.

  2. Acid fermentation of municipal sludge: the effect of sludge type and origin on the production and composition of volatile fatty acids

    Due to the more stringent legislations controlling discharges of wastewater treatment plants (WWTPs) and existing problems such as high sludge production, new wastewater treatment processes resulting in considerably reduced sludge production and more effective treatment would be of great value. In this study, the feasibility of implementing acid fermentation process on different types of municipal sludge to increase soluble chemical oxygen demand (SCOD), especially short-chain volatile fatty acids (VFAs) was investigated by batch and semi-continuous experiments. (Author)

  3. Effect of low temperature on highly unsaturated fatty acid biosynthesis in activated sludge.

    He, Su; Ding, Li-Li; Xu, Ke; Geng, Jin-Ju; Ren, Hong-Qiang

    2016-07-01

    Low temperature is a limiting factor for the microbial activity of activated sludge for sewage treatment plant in winter. Highly unsaturated fatty acid (UFA) biosynthesis, phospholipid fatty acid (PLFA) constituents and microbial structure in activated sludge at low temperature were investigated. Over 12 gigabases of metagenomic sequence data were generated with the Illumina HiSeq 2000 platform. The result showed 43.11% of phospholipid fatty acid (PLFA) in the activated sludge participated in UFA biosynthesis, and γ-Linolenic could be converted to Arachidonic acid at low temperature. The highly UFA biosynthesis in activated sludge was n-6 highly UFA biosynthesis, rather than n-3 highly UFA biosynthesis. The microbial community structures of activated sludge were analyzed by PLFA and high-throughput sequencing (HiSeq) simultaneously. Acidovorax, Pseudomonas, Flavobacterium and Polaromonas occupied higher percentage at 5°C, and genetic changes of highly UFA biosynthesis derived from microbial community structures change. PMID:27035483

  4. Combined Effect of Free Nitrous Acid Pretreatment and Sodium Dodecylbenzene Sulfonate on Short-Chain Fatty Acid Production from Waste Activated Sludge

    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...

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

    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

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

    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.

  7. Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation

    Anderson, C.; Malambo, D.H.; Gonzalez Perez, M.E.; Nobela, H.N.; De Pooter, L.; Spit, J.; Hooijmans, C.M.; Van de Vossenberg, J.; Greya, W.; Thole, B.; Van Lier, J.B.; Brdjanovic, D.

    2015-01-01

    In this research, three faecal sludge sanitizing methods—lactic acid fermentation, urea treatment and lime treatment—were studied for application in emergency situations. These methods were investigated by undertaking small scale field trials with pit latrine sludge in Blantyre, Malawi. Hydrated lim

  8. Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation

    Catherine Anderson; Dennis Hanjalika Malambo; Maria Eliette Gonzalez Perez; Happiness Ngwanamoseka Nobela; Lobke de Pooter; Jan Spit; Christine Maria Hooijmans; Jack van de Vossenberg; Wilson Greya; Bernard Thole; Jules B. van Lier; Damir Brdjanovic

    2015-01-01

    In this research, three faecal sludge sanitizing methods—lactic acid fermentation, urea treatment and lime treatment—were studied for application in emergency situations. These methods were investigated by undertaking small scale field trials with pit latrine sludge in Blantyre, Malawi. Hydrated lime was able to reduce the E. coli count in the sludge to below the detectable limit within 1 h applying a pH > 11 (using a dosage from 7% to 17% w/w, depending faecal sludge alkalinity), urea tre...

  9. Recovery of wastewater sludge components by acid hydrolysis

    Recktenwald, Michael; Karlsson, Ingemar

    2003-07-01

    Municipal waste water sludge is a complex product containing both valuable products and contaminants. The valuable products are phosphorus, organic matter and precipitants. The contaminants include heavy metals and organic micro pollutants. Consumers, farmers and their organisations are restrictive to utilisation of sludge on arable land. Disposal of organic waste will be prohibited in 2005. Thus the sludge treatment process, KREPRO, has been developed. From the waste water sludge, different fractions can be separated and reused such as organic fraction, phosphate, precipitants and carbon source. (author)

  10. Effect of acetic acid on lipid accumulation by glucose-fed activated sludge cultures

    Mondala, Andro; Hernandez, Rafael; French, Todd; McFarland, Linda; Sparks, Darrell; Holmes, William; Haque, Monica

    2012-01-01

    The effect of acetic acid, a lignocellulose hydrolysis by-product, on lipid accumulation by activated sludge cultures grown on glucose was investigated. This was done to assess the possible application of lignocellulose as low-cost and renewable fermentation substrates for biofuel feedstock production. Results: Biomass yield was reduced by around 54% at a 2 g L -1 acetic acid dosage but was increased by around 18% at 10 g L -1 acetic acid dosage relative to the control run. The final gravimetric lipid contents at 2 and 10 g L -1 acetic acid levels were 12.5 + 0.7% and 8.8 + 3.2% w/w, respectively, which were lower than the control (17.8 + 2.8% w/w). However, biodiesel yields from activated sludge grown with acetic acid (5.6 + 0.6% w/w for 2 g L -1 acetic acid and 4.2 + 3.0% w/w for 10 g L -1 acetic acid) were higher than in raw activated sludge (1-2% w/w). The fatty acid profiles of the accumulated lipids were similar with conventional plant oil biodiesel feedstocks. Conclusions: Acetic acid enhanced biomass production by activated sludge at high levels but reduced lipid production. Further studies are needed to enhance acetic acid utilization by activated sludge microorganisms for lipid biosynthesis.

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

    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

  12. Comparison of some spectroscopic and physico-chemical properties of humic acids extracted from sewage sludge and bottom sediments

    Polak, J.; Bartoszek, M.; Sułkowski, W. W.

    2009-04-01

    Comparison of the physico-chemical properties was carried out for humic acids extracted from sewage sludge and bottom sediments. The isolated humic acids were investigated by means of EPR, IR, UV/vis spectroscopic methods and elementary analysis AE. On the basis of earlier studies it was stated that humic acids extracted from sewage sludge can be divided into humic acids extracted from raw sewage sludge and from sewage sludge after the digestion process. The digestion process was found to have the most significant effect on the physico-chemical properties of humic acids extracted from sludge during sewage treatment. Humic acids extracted from sewage sludge had higher free radical concentration than humic acid extracted from bottom sediments. Values of the g-factor were similar for all studied samples. However, it is noteworthy that g-factor values for humic acid extracted from raw sewage sludge and from bottom sediments were lower in comparison to the humic acid extracted from sewage sludge after the fermentation processes. The IR spectra of all studied humic acids confirmed the presence of functional groups characteristic for humic substances. It was also observed that humic acids extracted from bottom sediments had a more aromatic character and contained less carbon, nitrogen and hydrogen than those extracted from the sewage sludge.

  13. K Basin Sludge Conditioning Testing. Nitric Acid Dissolution Testing of K East Area Sludge Composite, Small- and Large-Scale Testing

    This report describes work performed by Pacific Northwest National Laboratory (PNNL) for Numatec Hanford Corporation (NHC) to support the development of the K Basin Sludge Treatment System. For this work, testing was performed to examine the dissolution behavior of a K East Basin floor and Weasel Pit sludge composite, referred to as K East area sludge composite, in nitric acid at the following concentrations: 2 M, 4 M, 6 M and 7.8 M. With the exception of one high solids loading test the nitric acid was added at 4X the stoichiometric requirement (assuming 100% of the sludge was uranium metal). The dissolution tests were conducted at boiling temperatures for 24 hours. Most of the tests were conducted with approximately2.5 g of sludge (dry basis). The high solids loading test was conducted with approximately7 g of sludge. A large-scale dissolution test was conducted with 26.5 g of sludge and 620 mL of 6 M nitric acid. The objectives of this test were to (1) generate a sufficient quantity of acid-insoluble residual solids for use in leaching studies, and (2) examine the dissolution behavior of the sludge composite at a larger scale

  14. Spectroscopic studies of the progress of humification processes in humic acid extracted from sewage sludge

    Polak, J.; Sułkowski, W. W.; Bartoszek, M.; Papież, W.

    2005-06-01

    The humic acids extracted from sludge collected from the digestion chamber and the sludge drying beds were studied. The sludge samples were collected, dried and humic acids were extracted. The progress of the humification processes was studied with EPR, IR and NMR spectroscopic methods. For extracted humic acids, concentration of free radicals and g factor was determined with EPR. The presence of characteristic functional groups was confirmed with IR and NMR spectroscopy. To study the changes in content of the elements, the elemental analysis was performed to determine the percentage of carbon, hydrogen, nitrogen, sulfur and oxygen. Taking all the obtained results into account it was found that on the sewage drying beds, humification processes take place in the sludge. In the first two weeks when the sludge on the drying beds an intensive enrichment of humic acids in free radicals takes place. This is the result of the intensive humification process course after the stage in the fermentation chamber where the mesophilic fermentation takes place. Moreover, the humidity of sludge influences the intensive development of free radical concentration at the beginning of the storing period, whereas the humification processes still continue.

  15. Volatile fatty acids platform from thermally hydrolysed secondary sewage sludge enhanced through recovered micronutrients from digested sludge.

    Kumi, Philemon J; Henley, Adam; Shana, Achame; Wilson, Victoria; Esteves, Sandra R

    2016-09-01

    The extracellular polymeric substances and microbial cytoplasmic contents seem to hold inorganic ions and organic products, such as proteins and carbohydrates that are of critical importance for the metabolism of hydrolytic and acidogenic anaerobic microorganisms. The addition of soluble microbially recovered nutrients from thermally treated digestate sludge, for the fermentation of thermally hydrolysed waste activated sludge, resulted in higher volatile fatty acids yields (VFAs). The yield of VFAs obtained from the recovered microbial nutrients was 27% higher than the no micronutrients control, and comparable to the yield obtained using a micronutrients commercial recipe. In addition, the use of a low pH resulting from a high sucrose dose to select spore forming acidogenic bacteria was effective for VFA production, and yielded 20% higher VFAs than without the pH shock and this associated with the addition of recovered microbial nutrients would overcome the need to thermally pre-treat the inoculum. PMID:27206055

  16. Reaction of formic and nitric acids with Savannah River Site radioactive HLW sludge in the DWPF pretreatment steps

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) will combine borosilicate frit with highly radioactive waste sludge to produce glass waste forms for disposal. A key step in the DWPF will be acidification of the sludge with formic and nitric acids prior to vitrification. The reducing properties of formic acid will be used to reduce mercury (II) oxide and salts to elemental mercury. The mercury will then be steam-stripped, recovered, and purified. Another benefit of acidifying the sludge will be to reduce its viscosity so that a sludge-frit mixture can be pumped to the melter. The sludge viscosity decreases with pH as various sludge components dissolve with increasing acidity

  17. Effect of sewage sludge on formation of acidic ground water at a reclaimed coal mine

    Data on rock, ground water, vadose water, and vadose gas chemistry were collected for two years after sewage sludge was applied at a reclaimed surface coal mine in Pennsylvania to determine if surface-applied sludge is an effective barrier to oxygen influx, contributes metals and nutrients to ground water, and promotes the acidification of ground water. Acidity, sulfate, and metals concentrations were elevated in the ground water from spoil relative to unmined rock because of active oxidation of pyrite and dissolution of aluminosilicate, carbonate, and Mn-Fe-oxide minerals in the spoil. Concentrations of acidity, sulfate, metals (Fe, Mn, Al, Cd, Cu, Cr, Ni, Zn), and nitrate, and abundances of iron-oxidizing bacteria were elevated in the ground water from sludge-treated spoil relative to untreated spoil having a similar mineral composition; however, gaseous and dissolved oxygen concentrations did not differ between the treatments. Abundances of iron-oxidizing bacteria in the ground water samples were positively correlated with concentrations of ammonia, nitrate, acidity, metals, and sulfate. Concentrations of metals in vadose water samples (< 5-m depth) from sludge-treated spoil (pH 5.9) were not elevated relative to untreated spoil (pH 4.4). In contrast, concentrations of nitrate were elevated in vadose water samples from sludge-treated spoil, frequently exceeding 10 mg/L. Downgradient decreases in nitrate to less than 3 mg/L and increases in sulfate concentrations in underlying ground water could result from oxidation of pyrite by nitrate. Thus, sewage sludge added to pyritic spoil can increase the growth of iron-oxidizing bacteria, the oxidation of pyrite, and the acidification of ground water. Nevertheless, the overall effects on ground water chemistry from the sludge were small and probably short-lived relative to the effects from mining only

  18. Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation

    Catherine Anderson

    2015-10-01

    Full Text Available In this research, three faecal sludge sanitizing methods—lactic acid fermentation, urea treatment and lime treatment—were studied for application in emergency situations. These methods were investigated by undertaking small scale field trials with pit latrine sludge in Blantyre, Malawi. Hydrated lime was able to reduce the E. coli count in the sludge to below the detectable limit within 1 h applying a pH > 11 (using a dosage from 7% to 17% w/w, depending faecal sludge alkalinity, urea treatment required about 4 days using 2.5% wet weight urea addition, and lactic acid fermentation needed approximately 1 week after being dosed with 10% wet weight molasses (2 g (glucose/fructose/kg and 10% wet weight pre-culture (99.8% pasteurised whole milk and 0.02% fermented milk drink containing Lactobacillus casei Shirota. Based on Malawian prices, the cost of sanitizing 1 m3 of faecal sludge was estimated to be €32 for lactic acid fermentation, €20 for urea treatment and €12 for hydrated lime treatment.

  19. Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation.

    Anderson, Catherine; Malambo, Dennis Hanjalika; Perez, Maria Eliette Gonzalez; Nobela, Happiness Ngwanamoseka; de Pooter, Lobke; Spit, Jan; Hooijmans, Christine Maria; de Vossenberg, Jack van; Greya, Wilson; Thole, Bernard; van Lier, Jules B; Brdjanovic, Damir

    2015-11-01

    In this research, three faecal sludge sanitizing methods-lactic acid fermentation, urea treatment and lime treatment-were studied for application in emergency situations. These methods were investigated by undertaking small scale field trials with pit latrine sludge in Blantyre, Malawi. Hydrated lime was able to reduce the E. coli count in the sludge to below the detectable limit within 1 h applying a pH > 11 (using a dosage from 7% to 17% w/w, depending faecal sludge alkalinity), urea treatment required about 4 days using 2.5% wet weight urea addition, and lactic acid fermentation needed approximately 1 week after being dosed with 10% wet weight molasses (2 g (glucose/fructose)/kg) and 10% wet weight pre-culture (99.8% pasteurised whole milk and 0.02% fermented milk drink containing Lactobacillus casei Shirota). Based on Malawian prices, the cost of sanitizing 1 m³ of faecal sludge was estimated to be €32 for lactic acid fermentation, €20 for urea treatment and €12 for hydrated lime treatment. PMID:26528995

  20. Particle Size (Sieving) and Enthalpy (Acid Calorimetry) Analysis of Single-Pull K East Basin Floor and Pit Sludges

    This report presents the results of particle size analyses and calorimetry testing performed on selected single-pull sludge samples collected from the Hanford K East Basin between December 1998 and June 1999. The samples were collected as isolated cores predominantly from areas that had not been previously sampled (e.g., North Loadout Pit, Dummy Elevator Pit, Tech View Pit), or from areas in which the sludge composition had been altered since the last sampling (e.g., Weasel Pit). Particle size analyses were performed by washing wet sludge samples through a series of four sieves with openings of 250, 500, 1410, and 4000 microm. The loaded sieves were weighed before and after drying to obtain wet and dry particle size distributions. Knowledge of the particle size distribution is needed to design and predict the performance of the systems that will be used to retrieve, transport, and recover sludge. Also, sieving provides an opportunity to observe the components in the sludge. For example, during sieving of the sludge sample from the North Loadout Pit, significant quantities of organic ion exchange beads were observed. The uranium metal content and the particle size of the uranium metal in the K Basin sludge will largely determine the chemical reactivity of the sludge. In turn, the designs for the sludge handling and storage systems must be compatible with the reactivity of the sludge. Therefore, acid calorimetry was performed to estimate the uranium metal content of the sludge. For this testing, sludge samples were dissolved in nitric acid within a calibrated adiabatic calorimeter. The resulting dissolution enthalpy data were then used to discriminate between metallic uranium (minus3750 J/g in nitric acid) and uranium oxide (minus394 J/g in nitric acid). Results from this testing showed that the single-pull sludge samples contained little or no uranium metal

  1. Particle Size (Sieving) and Enthalpy (Acid Calorimetry) Analysis of Single-Pull K East Basin Floor and Pit Sludges

    PR Bredt; CH Delegard; AJ Schmidt; KL Silvers; BM Thornton; S Gano

    2000-12-22

    This report presents the results of particle size analyses and calorimetry testing performed on selected single-pull sludge samples collected from the Hanford K East Basin between December 1998 and June 1999. The samples were collected as isolated cores predominantly from areas that had not been previously sampled (e.g., North Loadout Pit, Dummy Elevator Pit, Tech View Pit), or from areas in which the sludge composition had been altered since the last sampling (e.g., Weasel Pit). Particle size analyses were performed by washing wet sludge samples through a series of four sieves with openings of 250, 500, 1410, and 4000 {micro}m. The loaded sieves were weighed before and after drying to obtain wet and dry particle size distributions. Knowledge of the particle size distribution is needed to design and predict the performance of the systems that will be used to retrieve, transport, and recover sludge. Also, sieving provides an opportunity to observe the components in the sludge. For example, during sieving of the sludge sample from the North Loadout Pit, significant quantities of organic ion exchange beads were observed. The uranium metal content and the particle size of the uranium metal in the K Basin sludge will largely determine the chemical reactivity of the sludge. In turn, the designs for the sludge handling and storage systems must be compatible with the reactivity of the sludge. Therefore, acid calorimetry was performed to estimate the uranium metal content of the sludge. For this testing, sludge samples were dissolved in nitric acid within a calibrated adiabatic calorimeter. The resulting dissolution enthalpy data were then used to discriminate between metallic uranium ({minus}3750 J/g in nitric acid) and uranium oxide ({minus}394 J/g in nitric acid). Results from this testing showed that the single-pull sludge samples contained little or no uranium metal.

  2. Combined γ-ray irradiation-activated sludge treatment of humic acid solution from landfill leachate

    Humic acid, which is a typical microbially refractory organic substance, was extracted from a landfill leachate. The humic acid solution (COD=367 mg 1-1; TOC=293 mg 1-1; BOD=27 mg 1-1) was applied to a batch scale activated sludge treatment after the modification of its biodegradability by γ-ray irradiation. The BOD increased to 64 mg 1-1 by irradiation of 15 kGy (1.5 Mrad), while the COD and TOC decreased to 231 and 230 mg 1-1, respectively. When the irradiated sample was treated with an activated sludge, the BOD decreased rapidly to a similar value as the unirradiated sample. The elimination efficiency of TOC by the sludge treatment was approximately equal to that obtained by irradiation of 15 kGy. These facts suggest a utility of applying microbial processes after radiation treatment of microbially refractory wastewaters. (author)

  3. Dissolution of sludges containing uranium dioxide and metallic uranium in nitric acid

    The dissolution in nitric acid of sludges containing uranium oxide and uranium has been modeled. That study has shown that it was necessary to continuously feed the dissolver to have an appropriate control of the reaction. If a unique procedure is deemed preferable, NH03 6M has been used

  4. Heavy metal extraction from PCB wastewater treatment sludge by sulfuric acid

    Heavy metals contaminated wastewater sludge is classified as hazardous solid waste and needs to be properly treated to prevent releasing heavy metals to the environment. In this study, the wastewater treatment sludge from a printed circuit board manufacturing plant was treated in a batch reactor by sulfuric acid to remove the contained heavy metals. The effects of sulfuric acid concentration and solid to liquid ratio on the heavy metal removal efficiencies were investigated. The experimental results showed that the total and individual heavy metal removal efficiencies increased with increasing sulfuric acid concentration, but decreased with increasing solid to liquid ratio. A mathematical model was developed to predict the residual sludge weights at varying sulfuric concentrations and solid to liquid ratios. The trivalent heavy metal ions, iron and chromium were more difficult to be removed than the divalent ions, copper, zinc, nickel, and cadmium. For 5 g/L solid to liquid ratio, more than 99.9% of heavy metals can be removed from the sludge by treating with 0.5 M sulfuric acid in 2 h.

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

    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

  6. Effect of sewage sludge on formation of acidic ground water at a reclaimed coal mine

    Cravotta, C.A., III

    1998-01-01

    Data on rock, ground water, vadose water, and vadose gas chemistry were collected for two years after sewage sludge was applied at a reclaimed surface coal mine in Pennsylvania to determine if surface-applied sludge is an effective barrier to oxygen influx, contributes metals and nutrients to ground water, and promotes the acidification of ground water. Acidity, sulfate, and metals concentrations were elevated in the ground water (6- to 21-m depth) from spoil relative to unmined rock because of active oxidation of pyrite and dissolution of aluminosilicate, carbonate, and Mn-Fe-oxide minerals in the spoil. Concentrations of acidity, sulfate, metals (Fe, Mn, Al, Cd, Cu, Cr, Ni, Zn), and nitrate, and abundances of iron-oxidizing bacteria were elevated in the ground water from sludge-treated spoil relative to untreated spoil having a similar mineral composition; however, gaseous and dissolved oxygen concentrations did not differ between the treatments. Abundances of iron-oxidizing bacteria in the ground water samples were positively correlated with concentrations of ammonia, nitrate, acidity, metals, and sulfate. Concentrations of metals in vadose water samples (water samples from sludge-treated spoil, frequently exceeding 10 mg/L. Downgradient decreases in nitrate to less than 3 mg/L and increases in sulfate concentrations in underlying ground water could result from oxidation of pyrite by nitrate. Thus, sewage sludge added to pyritic spoil can increase the growth of iron-oxidizing bacteria, the oxidation of pyrite, and the acidification of ground water. Nevertheless, the overall effects on ground water chemistry from the sludge were small and probably short-lived relative to the effects from mining only.

  7. Effect of Volatile Fatty Acids and Trimethylamine on Nitrification in Activated Sludge

    Eilersen, Ann Marie; Henze, Mogens; Kløft, Lene

    1994-01-01

    The effect of volatile fatty acids and trimethylamine on the nitrification activity of activated sludge was studied in laboratory batch experiments. The critical concentration of inhibitor IK at which the activity ceases was determined by modelling. IK values for ammonia oxidation were found to be...... wastewater stripped of sulphide showed that volatile fatty acids and trimethylamine alone cannot account for the inhibition of the nitrification activity, indicating that other factors are also involved....

  8. Occurrence and point source characterization of perfluoroalkyl acids in sewage sludge.

    Alder, Alfredo C; van der Voet, Juergen

    2015-06-01

    The occurrence and levels of perfluoroalkyl acids (PFAAs) emitted from specific pollution sources into the aquatic environment in Switzerland were studied using digested sewage sludges from 45 wastewater treatment plants in catchments containing a wide range of potential industrial emitters. Concentrations of individual PFAAs show a high spatial and temporal variability, which infers different contributions from industrial technologies and activities. Perfluorooctane sulfonic acid (PFOS) was generally the predominant PFAA with concentrations varying between 4 and 2440μgkg(-1) (median 75μgkg(-1)). Elevated emissions were especially observed in catchments capturing discharges from metal plating industries (median 82μgkg(-1)), aqueous firefighting foams (median 215μgkg(-1)) and landfill leachates (median 107μgkg(-1)). Some elevated perfluoroalkyl carboxylic acids (PFCAs) levels could be attributed to emissions from textile finishing industries with concentrations up to 233μgkg(-1) in sewage sludge. Assuming sorption to sludge for PFOS and PFCAs of 15% and 2%, respectively, concentrations in wastewater effluents up to the low μgL(-1) level were estimated. Even if wastewater may be expected to be diluted between 10 and 100 times by the receiving waters, elevated concentrations may be reached at specific locations. Although sewage sludge is a minor compartment for PFAAs in WWTPs, these investigations are helpful for the identification of hot-spots from industrial emitters as well as to estimate monthly average concentrations in wastewater. PMID:25176581

  9. Comparative anti-dandruff efficacy between a tar and a non-tar shampoo.

    Piérard-Franchimont, C; Piérard, G E; Vroome, V; Lin, G C; Appa, Y

    2000-01-01

    A randomized double-blind clinical study was conducted on two groups of 30 volunteers using either a non-tar shampoo (2% salicylic acid, 0.75% piroctone olamine and 0.5% elubiol) or a 0.5% coal tar shampoo. Subjects were diagnosed as having moderate to marked dandruff. The study consisted of a 3-week washout, followed by a 4-week treatment and a 4-week posttreatment regression phase. The clinical evaluations and subject self-assessments showed that the non-tar shampoo was as effective as the tar shampoo. Both received high approval ratings (> or =70%). Biometrological methods proved to be more sensitive than clinical evaluations to assess the efficacy of the shampoos. The non-tar shampoo yielded a significantly better reduction of Malassezia spp. counts (ppiroctone olamine and elubiol exhibited increased beneficial effects compared to the coal tar shampoo. PMID:10773717

  10. Phthalic acid and benzo[a]pyrene in soil-plant-water systems amended with contaminated sewage sludge

    Mougin, C.; Dappozze, F.; Brault, A.;

    2006-01-01

    than 30% after 90 days in the situation of direct soil contamination, amendment with contaminated digested or composted sludge. It is reduced to 10% in the presence of the raw sludge. In that case, the values of phospholipidic fatty acids and dehydrogenase activity are the highest. By contrast, benzo...

  11. Effects of Composted and Thermally Dried Sewage Sludges on Soil and Soil Humic Acid Properties

    J.M.FERN(A)NDEZ; N.SENESI; C.PLAZA; G.BRUNETTI; A.POLO

    2009-01-01

    The effect of annual additions of composted sewage sludge (CS) and thermally dried sewage sludge (TS) at 80 t ha-1 on soil chemical properties was investigated for three years in a field experiment under semiarid conditions.Humie acids (HAs) isolated by conventional procedures from CS,TS,and unamended (SO) and sludge amended soils were analysed for elemental (C,H,N,S and O) and acidic functional groups (carboxylic and phenolic) and by ultraviolet-visible,Fourier transform infrared and fluorescence spectroscopies.With respect to CS,TS had similar pH and total P and K contents,larger dry matter,total organic C,total N.and C/N ratio and smaller ash content and electrical conductivity.Amendment with both CS and TS induced a number of modifications in soil properties,including an increase of pH,electrical conductivity,total organic C,total N,and available P.The CS-HA had greater O,total acidity,carboxyl,and phenolic OH group contents and smaller C and H contents than TS-HA.The CS-HA and TS-HA had larger N and S contents,smaller C,O and acidic functional group contents,and lower aromatic polycondensation and humification degrees than SO-HA.Amended soil-HAs showed C,H,N and S contents larger than SO-HA,suggesting that sludge HAs were partially incorporated into soil HAs.These effects were more evident with increasing number of sludge applications.

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

    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

  13. Application of acidic thermal treatment for one- and two-stage anaerobic digestion of sewage sludge.

    Takashima, M; Tanaka, Y

    2010-01-01

    The effectiveness of acidic thermal treatment (ATT) was examined in a 106-day continuous experiment, when applied to one- or two-stage anaerobic digestion of sewage sludge (4.3% TS). The ATT was performed at 170 °C and pH 5 for 1 hour (sulfuric acid for lowering pH). The one-stage process was mesophilic at 20 days hydraulic retention time (HRT), and incorporated the ATT as pre-treatment. The two-stage process consisted of a thermophilic digester at 5 days HRT and a mesophilic digester at 15 days HRT, and incorporated the ATT as interstage-treatment. On average, VSS reduction was 48.7% for the one-stage control, 65.8% for the one-stage ATT, 52.7% for the two-stage control and 67.6% for the two-stage ATT. Therefore, VSS reduction was increased by 15-17%, when the ATT was combined in both one- and two-stage processes. In addition, the dewaterability of digested sludge was remarkably improved, and phosphate release was enhanced. On the other hand, total methane production did not differ significantly, and color generation was noted in the digested sludge solutions with the ATT. In conclusion, the anaerobic digestion with ATT can be an attractive alternative for sludge reduction, handling, and phosphorus recovery. PMID:21099053

  14. Biosorption of Acid Yellow 17 from aqueous solution by non-living aerobic granular sludge

    Batch biosorption experiments were carried out for the removal of Acid Yellow 17 from aqueous solution using non-living aerobic granular sludge as an effective biosorbent. The effects of solution pH value, biosorbent dosage, initial Acid Yellow 17 concentration, NaCl concentration and temperature on the biosorption were investigated. The experimental results indicate that this process was highly dependent on pH value and the pH value of 2.0 was favorable. The Temkin isotherm was more applicable for describing the biosorption equilibrium at the whole concentration range than the Freundlich and Langmuir isotherm. The results of kinetics study show that the pseudo-second-order model fitted to the experimental data well. Both intraparticle diffusion and boundary layer diffusion might affect the biosorption rate. Thermodynamic studies demonstrate that the biosorption process was spontaneous and exothermic. The FTIR analysis before and after Acid Yellow 17 binding indicated that functional groups such as amine, hydroxyl, carboxyl and either on the non-living aerobic granular sludge would be the active binding sites for the biosorption of the studied dye. These results show that non-living aerobic granular sludge could be effectively used as a low-cost and alternative biosorbent for the removal of Acid Yellow 17 dye from wastewater.

  15. [Effect of municipal sludge and chemical fertilizers on phthalic acid esters (PAEs) contents in Ipomoea aquatica grown on paddy soils].

    Cai, Quanying; Mo, Cehui; Zhu, Xizhen; Wu, Qitang; Wang, Boguang; Jiang, Chengai; Li, Haiqin

    2003-11-01

    GC/MS determinations on six phthalic acid esters (PAEs) in Ipomoea aquatic grown on potted paddy soil fertilized with municipal sludge and chemical fertilizers showed that the total contents of PAEs (sigma PAEs) in Ipomoea aquatic aboveground parts ranged from 2.129 mg.kg-1 to 7.111 mg.kg-1, decreasing in order of Guangzhou sludge + fertilizers (7.111 mg.kg-1) > Guangzhou sludge (4.767 mg.kg-1) > Foshan sludge (3.569 mg.kg-1) > Foshan sludge + fertilizers (3.305 mg.kg-1) > fertilizers (2.638 mg.kg-1) > control (2.129 mg.kg-1), indicating that compared with control, fertilization increased sigma PAEs in Ipomoea aquatica to a different extent. Only certain compounds of PAEs in different treatments of Ipomoea aquatica were dominant, e.g., butylbenzyl phthalate (BBP) in control, chemical fertilizers, Foshan sludge, and Guangzhou sludge accounted for 40% to 80% of sigma PAEs, di-n-butyl phthalate(DnBP) in foshan sludge + chemical fertilizers accounted for 56%, while di-n-octyl phthalate(DnOP), di(2-ethylhexyl)phthalate(DEHP) and BBP in Guangzhou sludge + chemical fertilizers accounted for approximately 30%. sigma PAEs and the contents of its most compounds were higher in the plants of Ipomoea aquatica than in its roots to a different extent. PMID:14997666

  16. Structural characterization of humic acids, extracted from sewage sludge during composting, by thermochemolysis–gas chromatography–mass spectrometry

    Amir, Soumia; Hafidi, Mohamed; Lemee, Laurent; Merlina, Georges; Guiresse, Maritxu; Pinelli, Eric; Revel, Jean-Claude; Bailly, Jean-René; Amblès, André

    2006-01-01

    Thermochemolysis coupled with gas chromatography and mass spectrometry were applied to determine the structure of humic acids (HA) extracted from a sewage sludge and straw mixture at different steps of composting. The HA extracted from sludge mixture released various compounds, such as mono-, di-, tri-methoxy (alkyl) benzene and (alkyl) benzoic acids, which originated from lignin like derivatives of phydroxyphenyl, guiaicyl and syringyl units. In addition, other aromatic non-lignin derived st...

  17. K Basin Sludge Conditioning Process Testing Project. Results from Test 4, ''Acid Digestion of Mixed-Bed Ion Exchange Resin''

    Approximately 73 m3 of heterogeneous solid material, ''sludge,'' (upper bound estimate, Packer 1997) have accumulated at the bottom of the K Basins in the 100 K Area of the Hanford Site. This sludge is a mixture of spent fuel element corrosion products, ion exchange materials (organic and inorganic), graphite-based gasket materials, iron and aluminum metal corrosion products, sand, and debris (Makenas et al. 1996, 1997). In addition, small amounts of polychlorinated biphenyls (PCBs) have been found. Ultimately, it is planned to transfer the K Basins sludge to the Hanford double shell tanks (DSTs). The Hanford Spent Nuclear Fuel (HSNF) project has conducted a number of evaluations to examine technology and processing alternatives to pretreat K Basin sludge to meet storage and disposal requirements. From these evaluations, chemical pretreatment has been selected to address criticality issues, reactivity, and the destruction or removal of PCBs before the K Basin sludge can be transferred to the DSTs. Chemical pretreatment, referred to as the K Basin sludge conditioning process, includes nitric acid dissolution of the sludge (with removal of acid insoluble solids), neutrons absorber addition, neutralization, and reprecipitation. Laboratory testing is being conducted by the Pacific Northwest National Laboratory (PNNL) to provide data necessary to develop the sludge conditioning process

  18. Coal tar in dermatology

    Roelofzen, J.H.J.; Aben, K.K.H.; Van Der Valk, P.G.M.; Van Houtum, J.L.M.; Van De Kerkhof, P.C.M.; Kiemeney, L.A.L.M. [Radboud University Nijmegen Medical Center, Nijmegen (Netherlands). Dept. of Dermatology

    2007-07-01

    Coal tar is one of the oldest treatments for psoriasis and eczema. It has anti-inflammatory, antibacterial, antipruritic and antimitotic effects. The short-term side effects are folliculitis, irritation and contact allergy. Coal tar contains carcinogens. The carcinogenicity of coal tar has been shown in animal studies and studies in occupational settings. There is no clear evidence of an increased risk of skin tumors or internal tumors. Until now, most studies have been fairly small and they did not investigate the risk of coal tar alone, but the risk of coal tar combined with other therapies. New, well-designed, epidemiological studies are necessary to assess the risk of skin tumors and other malignancies after dermatological use of coal tar.

  19. Validation Testing of the Nitric Acid Dissolution Step Within the K Basin Sludge Pretreatment Process

    AJ Schmidt; CH Delegard; KL Silvers; PR Bredt; CD Carlson; EW Hoppe; JC Hayes; DE Rinehart; SR Gano; BM Thornton

    1999-03-24

    The work described in this report involved comprehensive bench-scale testing of nitric acid (HNO{sub 3}) dissolution of actual sludge materials from the Hanford K East (KE) Basin to confirm the baseline chemical pretreatment process. In addition, process monitoring and material balance information was collected to support the development and refinement of process flow diagrams. The testing was performed by Pacific Northwest National Laboratory (PNNL)for the US Department of Energy's Office of Spent Fuel Stabilization (EM-67) and Numatec Hanford Corporation (NHC) to assist in the development of the K Basin Sludge Pretreatment Process. The baseline chemical pretreatment process for K Basin sludge is nitric acid dissolution of all particulate material passing a 1/4-in. screen. The acid-insoluble fraction (residual solids) will be stabilized (possibly by chemical leaching/rinsing and grouting), packaged, and transferred to the Hanford Environmental Restoration Disposal Facility (ERDF). The liquid fraction is to be diluted with depleted uranium for uranium criticality safety and iron nitrate for plutonium criticality safety, and neutralized with sodium hydroxide. The liquid fraction and associated precipitates are to be stored in the Hanford Tank Waste Remediation Systems (TWRS) pending vitrification. It is expected that most of the polychlorinated biphenyls (PCBs), associated with some K Basin sludges, will remain with the residual solids for ultimate disposal to ERDF. Filtration and precipitation during the neutralization step will further remove trace quantities of PCBs within the liquid fraction. The purpose of the work discussed in this report was to examine the dissolution behavior of actual KE Basin sludge materials at baseline flowsheet conditions and validate the.dissolution process step through bench-scale testing. The progress of the dissolution was evaluated by measuring the solution electrical conductivity and concentrations of key species in the

  20. Validation Testing of the Nitric Acid Dissolution Step Within the K Basin Sludge Pretreatment Process

    The work described in this report involved comprehensive bench-scale testing of nitric acid (HNO3) dissolution of actual sludge materials from the Hanford K East (KE) Basin to confirm the baseline chemical pretreatment process. In addition, process monitoring and material balance information was collected to support the development and refinement of process flow diagrams. The testing was performed by Pacific Northwest National Laboratory (PNNL)for the US Department of Energy's Office of Spent Fuel Stabilization (EM-67) and Numatec Hanford Corporation (NHC) to assist in the development of the K Basin Sludge Pretreatment Process. The baseline chemical pretreatment process for K Basin sludge is nitric acid dissolution of all particulate material passing a 1/4-in. screen. The acid-insoluble fraction (residual solids) will be stabilized (possibly by chemical leaching/rinsing and grouting), packaged, and transferred to the Hanford Environmental Restoration Disposal Facility (ERDF). The liquid fraction is to be diluted with depleted uranium for uranium criticality safety and iron nitrate for plutonium criticality safety, and neutralized with sodium hydroxide. The liquid fraction and associated precipitates are to be stored in the Hanford Tank Waste Remediation Systems (TWRS) pending vitrification. It is expected that most of the polychlorinated biphenyls (PCBs), associated with some K Basin sludges, will remain with the residual solids for ultimate disposal to ERDF. Filtration and precipitation during the neutralization step will further remove trace quantities of PCBs within the liquid fraction. The purpose of the work discussed in this report was to examine the dissolution behavior of actual KE Basin sludge materials at baseline flowsheet conditions and validate the.dissolution process step through bench-scale testing. The progress of the dissolution was evaluated by measuring the solution electrical conductivity and concentrations of key species in the dissolver

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

    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. Evaluation Of Sludge Heel Dissolution Efficiency With Oxalic Acid Cleaning At Savannah River Site

    The chemical cleaning process baseline strategy at the Savannah River Site was revised to improve efficiency during future execution of the process based on lessons learned during previous bulk oxalic acid cleaning activities and to account for operational constraints imposed by safety basis requirements. These improvements were also intended to transcend the difficulties that arise from waste removal in higher rheological yield stress sludge tanks. Tank 12 implemented this improved strategy and the bulk oxalic acid cleaning efforts concluded in July 2013. The Tank 12 radiological removal results were similar to previous bulk oxalic acid cleaning campaigns despite the fact that Tank 12 contained higher rheological yield stress sludge that would make removal more difficult than the sludge treated in previous cleaning campaigns. No appreciable oxalate precipitation occurred during the cleaning process in Tank 12 compared to previous campaigns, which aided in the net volume reduction of 75-80%. Overall, the controls established for Tank 12 provide a template for an improved cleaning process

  3. Evaluation Of Sludge Heel Dissolution Efficiency With Oxalic Acid Cleaning At Savannah River Site

    Sudduth, Christie; Vitali, Jason; Keefer, Mark

    2014-01-08

    The chemical cleaning process baseline strategy at the Savannah River Site was revised to improve efficiency during future execution of the process based on lessons learned during previous bulk oxalic acid cleaning activities and to account for operational constraints imposed by safety basis requirements. These improvements were also intended to transcend the difficulties that arise from waste removal in higher rheological yield stress sludge tanks. Tank 12 implemented this improved strategy and the bulk oxalic acid cleaning efforts concluded in July 2013. The Tank 12 radiological removal results were similar to previous bulk oxalic acid cleaning campaigns despite the fact that Tank 12 contained higher rheological yield stress sludge that would make removal more difficult than the sludge treated in previous cleaning campaigns. No appreciable oxalate precipitation occurred during the cleaning process in Tank 12 compared to previous campaigns, which aided in the net volume reduction of 75-80%. Overall, the controls established for Tank 12 provide a template for an improved cleaning process.

  4. Fate and effect of naphthenic acids on oil refinery activated sludge wastewater treatment systems.

    Misiti, Teresa; Tezel, Ulas; Pavlostathis, Spyros G

    2013-01-01

    Naphthenic acids (NAs) are a complex group of alkyl-substituted acyclic, monocyclic and polycyclic carboxylic acids present in oil sands process waters, crude oil, refinery wastewater and petroleum products. Crude oil, desalter brine, influent, activated sludge mixed liquor and effluent refinery samples were received from six United States refineries. The total acid number (TAN) of the six crudes tested ranged from 0.12 to 1.5 mg KOH/g crude oil and correlated to the total NA concentration in the crudes. The total NA concentration in the desalter brine, influent, activated sludge mixed liquor and effluent samples ranged from 4.2 to 40.4, 4.5 to 16.6, 9.6 to 140.3 and 2.8 to 11.6 mg NA/L, respectively. The NAs in all wastewater streams accounted for less than 16% of the total COD, indicating that many other organic compounds are present and that NAs are a minor component in refinery wastewaters. Susceptibility tests showed that none of the activated sludge heterotrophic microcosms was completely inhibited by NAs up to 400 mg/L. Growth inhibition ranging from 10 to 59% was observed in all microcosms at and above 100 mg NA/L. NAs chronically-sorbed to activated sludge mixed liquor biomass and powdered activated carbon (PAC) were recalcitrant and persistent. More than 80% of the total NAs remained in the solid phase at the end of the 10-day desorption period (five successive desorption steps). Throughout a 90-day incubation period, the total NA concentration decreased by 33 and 51% in PAC-free and PAC-containing mixed liquor microcosms, respectively. The lower molecular weight fraction of NAs was preferentially degraded in both mixed liquors. The persistence of the residual, higher molecular weight NAs is likely a combination of molecular recalcitrance and decreased bioavailability when chronically-sorbed to the biomass and/or PAC. PMID:23141768

  5. Utilizing acid mine drainage sludge and coal fly ash for phosphate removal from dairy wastewater.

    Wang, Y R; Tsang, Daniel C W; Olds, William E; Weber, Paul A

    2013-01-01

    This study aims to investigate a new and sustainable approach for the reuse of industrial by-products from wastewater treatment. The dairy industry produces huge volumes of wastewater, characterized by high levels of phosphate that can result in eutrophication and degradation of aquatic ecosystems. This study evaluated the application of acid mine drainage (AMD) sludge, coal fly ash, and lignite as low-cost adsorbents for the removal of phosphate from dairy wastewater. Material characterization using X-ray fluorescence, X-ray diffraction, and Brunauer-Emmett-Teller surface area analysis revealed significant amounts of crystalline/amorphous Fe/Al/Si/Ca-based minerals and large surface areas of AMD sludge and fly ash. Batch adsorption isotherms were best described using the Freundlich model. The Freundlich distribution coefficients were 13.7 mg(0.577) L(0.423) g(-1) and 16.9 mg(0.478) L(0.522) g(-1) for AMD sludge and fly ash, respectively, and the nonlinearity constants suggested favourable adsorption for column applications. The breakthrough curves of fixed-bed columns, containing greater than 10 wt% of the waste materials (individual or composite blends) mixed with sand, indicated that phosphate breakthrough did not occur within 100 pore volumes while the cumulative removal was 522 and 490 mg kg(-1) at 10 wt% AMD sludge and 10 wt% fly ash, respectively. By contrast, lignite exhibited negligible phosphate adsorption, possibly due to small amounts of inorganic minerals suitable for phosphate complexation and limited surface area. The results suggest that both AMD sludge and fly ash were potentially effective adsorbents if employed individually at a ratio of 10 wt% or above for column application. PMID:24617077

  6. Effect of Volatile Fatty Acids and Trimethylamine on Denitrification in Activated Sludge

    Eilersen, Ann Marie; Henze, Mogens; Kløft, Lene

    1995-01-01

    with the strongest effect, n-butyric acid has a moderate effect, while TMA only have a small effect in stimulating the rates. Propionic, isobutyric, n-valeric, isovaleric and caproic acid inhibit denitrification, nitrate reduction being more inhibited than nitrite reduction. The inhibitor concentration......M for n-valeric, 18 mM for isovaleric and 105 mM for caproic acid. KI values for nitrite reduction were found to be 196 mM for propionic, 32 mM for isobutyric, 57 mM for n-valeric, 18 mM for isovaleric and 110 mM for caproic acid. Inhibition of the rate of hydrolysis could not be determined....... Anaerobically treated wastewaters from fish, potato and onion industries all stimulated denitrification. Reject water from anaerobic treatment of excess sludge had no significant effect on the denitrification processes. For isobutyric, isovaleric and n-valeric acid the undissociated compounds appear to act as...

  7. Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of Composite K East Canister Sludge

    Laboratory tests were performed to examine mixed nitric/hydrofluoric acid leach treatments for decontaminating dissolver residual solids (KECDVSR24H-2) produced during a 20- to 24-hr dissolution of a composite K East (KE) Basin canister sludge in 95 C 6 M nitric acid (HNO3). The scope of this testing has been described in Section 4.5 of ''Testing Strategy to Support the Development of K Basin Sludge Treatment Process'' (Flament 1998). Radionuclides sorbed or associated with the residual solids generated in the K Basin sludge treatment process can restrict disposal of this solid to the Environmental Restoration Disposal Facility (ERDF). The starting dissolver residual solid for this testing, KECDVSR24H-2, contains radionuclides at concentrations which exceed the ERDF Waste Acceptance Criteria for TRU by about a factor of 70, for 239Pu by a factor of 200, and for 241Am by a factor of 50. The solids also exceed the ERDF criterion for 137Cs by a factor of 2 and uranium by a factor of 5. Therefore, the radionuclides of greatest interest in this leaching study are first 239Pu and 241Am (both components of TRU) and then uranium and 137Cs

  8. Reuse of acid coagulant-recovered drinking waterworks sludge residual to remove phosphorus from wastewater

    Yang, Lan; Wei, Jie; Zhang, Yumei; Wang, Jianli; Wang, Dongtian

    2014-06-01

    Acid coagulant-recovered drinking waterworks sludge residual (DWSR) is a waste product from drinking waterworks sludge (DWS) treatment with acid for coagulant recovery. In this study, we evaluated DWSR as a potential phosphorus (P) removing material in wastewater treatment by conducting a series of batch and semi-continuous tests. Batch tests were carried out to study the effects of pH, initial concentration, and sludge dose on P removal. Batch test results showed that the P removal efficiency of DWSR was highly dependent on pH. Calcinated DWSR (C-DWSR) performed better in P removal than DWSR due to its higher pH. At an optimum initial pH value of 5-6 and a sludge dose of 10 g/L, the P removal rates of DWSR and DWS decreased from 99% and 93% to 84% and 14%, respectively, and the specific P uptake of DWSR and DWS increased from 0.19 and 0.19 mg P/g to 33.60 and 5.72 mg P/g, respectively, when the initial concentration was increased from 2 to 400 mg/L. The effective minimum sludge doses of DWSR and DWS were 0.5 g/L and 10 g/L, respectively, when the P removal rates of 90% were obtained at an initial concentration of 10 mg/L. Results from semi-continuous test indicated that P removal rates over 99% were quickly achieved for both synthetic and actual wastewater (lake water and domestic sewage). These rates could be maintained over a certain time under a certain operational conditions including sludge dose, feed flow, and initial concentration. The physicochemical properties analysis results showed that the contents of aluminum (Al) and iron (Fe) in DWSR were reduced by 50% and 70%, respectively, compared with DWS. The insoluble Al and Fe hydroxide in DWS converted into soluble Al and Fe in DWSR. Metal leaching test results revealed that little soluble Al and Fe remained in effluent when DWSR was used for P removal. We deduced that chemical precipitation might be the major action for P removal by DWSR and that adsorption played only a marginal role.

  9. An open label prospective randomized trial to compare the efficacy of coal tar-salicylic acid ointment versus calcipotriol/betamethasone dipropionate ointment in the treatment of limited chronic plaque psoriasis

    Sujay Khandpur

    2014-01-01

    Full Text Available Background: Chronic plaque psoriasis is a common papulosquamous skin disorder, for which a number of topical agents are being used including coal tar, topical steroids and more recently topical calcipotriol/betamethasone dipropionate. There is no study comparing purified coal tar preparation with calcipotriol/betamethasone dipropionate ointment in limited chronic plaque psoriasis. Aims and Objectives: A prospective randomized open label controlled trial to compare the efficacy and safety of topical application of coal tar-salicylic acid ointment with calcipotriol/betamethasone dipropionate ointment applied once at night for 12 weeks for the treatment of limited chronic plaque psoriasis. Materials and Methods: A total of 62 patients of limited chronic plaque psoriasis (body surface area <10% were randomized into two treatment groups: Group A received topical application of 6% coal tar with 3% salicylic acid ointment and Group B received calcipotriol/betamethasone dipropionate, once at night for 12 weeks. Results were assessed based on psoriasis area severity index (PASI scores and patient global assessment (PGA at each visit. Results: Mean PASI was significantly lower at week 2 (P = 0.01 and week 4 follow-up (P = 0.05 and the mean reduction in PASI was significantly higher at week 2 (P = 0.02 with calcipotriol/betamethasone than coal tar-salicylic acid, but this difference was not sustained at subsequent follow-up visits. Similarly, PGA scores at weeks 2 and 4 were significantly lower with calcipotriol/betamethasone dipropionate ointment (P = 0.003 and P = 0.007 respectively. There was no significant difference in any parameter during subsequent follow-up visits or at the end of the treatment phase (12 weeks. Conclusion: Topical nightly application of calcipotriol/betamethasone dipropionate ointment leads to an initial, more rapid reduction in disease severity, but the overall outcome parameters are comparable in the two treatment groups.

  10. Production of anti-Gordonia amarae mycolic acid polyclonal antibody for detection of mycolic acid-containing bacteria in activated sludge foam.

    Iwahori, K; Miyata, N; Takata, N; Morisada, S; Mochizuki, T

    2001-01-01

    Mycolic acid-containing actinomycetes (mycolata) are considered the causative agents of foaming of activated sludge and scum formation in activated sludge treatment plants. In this study, the production of anti-Gordonia amarae mycolic acid polyclonal antibodies was investigated. Rabbits were immunized with a conjugate of keyhole limpet hemocyanin and mycolic acids of G. amarae, which contained 48 to 56 carbon atoms (average, 52.0). Enzyme-linked immunosorbent assay (ELISA) demonstrated that the polyclonal antibodies could recognize cells of G. amarae ranging from 0.1 to 10 microg. The antibodies also reacted with other tested mycolata strains belonging to the genera Nocardia, Rhodococcus, Dietzia, Mycobacterium and Tsukamurella. However, reactivities against other gram-positive and gram-negative bacteria not containing mycolic acid were negligible or much lower. The results indicate that the anti-G. amarae mycolic acid antibodies show a reactivity selective for a group of mycolata involved in the foaming of activated sludge. PMID:16233121

  11. Heavy metal removal from sludge with organic chelators: Comparative study of N, N-bis(carboxymethyl) glutamic acid and citric acid.

    Suanon, Fidèle; Sun, Qian; Dimon, Biaou; Mama, Daouda; Yu, Chang-Ping

    2016-01-15

    The applicability and performance of a new generation of biodegradable chelator, N, N-Bis(carboxymethyl) glutamic acid (GLDA), for extracting heavy metals from sewage sludge was carried out and compared with citric acid (CA). Targeted metals included Cd, Co, Cu, Zn, Ni and Cr, and their contents in the raw sludge were 63.1, 73.4, 1103.2, 2060.3, 483.9 and 604.1 mg kg(-1) (dry sludge basis), respectively. Metals were divided into six fractions including water soluble, exchangeable, carbonates bound, Fe-Mn bound, organic matters bound and residual fraction via chemical fractionation. Washing results showed that in general GLDA exhibited better performance compared with CA, with removal efficiency of 83.9, 87.3, 81.2, 85.6, 89.3 and 90.2% for Cd, Co, Cu, Zn, Ni and Cr, respectively at equilibrium pH = 3.3. Residual metals were better stabilized in the GLAD-washed sludge than in the CA-washed sludge, and were mostly tightly bonded to the residual fraction. Furthermore, CA promoted phosphorus (P) release while GLDA had an opposite effect and tended to retain P within sludge, which could be beneficial for further application in agricultural use. Findings from this study suggested that GLDA could be a potential replacement for refractory and less environmentally-friendly chelators in the extraction of metals from sludge. PMID:26520041

  12. Combined Effect of Free Nitrous Acid Pretreatment and Sodium Dodecylbenzene Sulfonate on Short-Chain Fatty Acid Production from Waste Activated Sludge.

    Zhao, Jianwei; Liu, Yiwen; Ni, Bingjie; Wang, Qilin; Wang, Dongbo; Yang, Qi; Sun, Yingjie; Zeng, Guangming; Li, Xiaoming

    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 presence on SCFA production as well as the corresponding mechanisms have never been documented. This work therefore aims to provide such support. Experimental results showed that the combination of FNA and SDBS treatment not only improved SCFA accumulation but also shortened the fermentation time. The maximal SCFA accumulation of 334.5 mg chemical oxygen demand (COD)/g volatile suspended solids (VSS) was achieved at 1.54 mg FNA/L treatment and 0.02 g/g dry sludge, which was respectively 1.79-fold and 1.41-fold of that from FNA treatment and sludge containing SDBS alone. Mechanism investigations revealed that the combined FNA pretreatment and SDBS accelerated solubilization, hydrolysis, and acidification steps but inhibited the methanogenesis. All those observations were in agreement with SCFA enhancement. PMID:26868898

  13. Recovery of volatile fatty acids from fermentation of sewage sludge in municipal wastewater treatment plants.

    Longo, S; Katsou, E; Malamis, S; Frison, N; Renzi, D; Fatone, F

    2014-10-01

    This work investigated the pilot scale production of short chain fatty acids (SCFAs) from sewage sludge through alkaline fermentation and the subsequent membrane filtration. Furthermore, the impact of the fermentation liquid on nutrient bioremoval was examined. The addition of wollastonite in the fermenter to buffer the pH affected the composition of the carbon source produced during fermentation, resulting in higher COD/NH4-N and COD/PO4-P ratios in the liquid phase and higher content of propionic acid. The addition of wollastonite decreased the capillary suction time (CST) and the time to filter (TTF), resulting in favorable dewatering characteristics. The sludge dewatering characteristics and the separation process were adversely affected from the use of caustic soda. When wollastonite was added, the permeate flux increased by 32%, compared to the use of caustic soda. When fermentation liquid was added as carbon source for nutrient removal, higher removal rates were obtained compared to the use of acetic acid. PMID:25459853

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

    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

  15. Enhancement of sludge anaerobic biodegradability by combined microwave-H2O2 pretreatment in acidic conditions.

    Eswari, Parvathy; Kavitha, S; Kaliappan, S; Yeom, Ick-Tae; Banu, J Rajesh

    2016-07-01

    The aim of this study was to increase the sludge disintegration and reduce the cost of microwave (MW) pretreatment. Thermodynamic analysis of MW hydrolysis revealed the best fit with a first-order kinetic model at a specific energy of 18,600 kJ/kg total solids (TS). Combining H2O2 with MW resulted in a significant increment in solubilization from 30 to 50 % at 18,600 kJ/kg TS. The pH of H2O2-assisted MW-pretreated sludge (MW + H2O2) was in the alkaline range (pH 9-10), and it made the sludge unfavorable for subsequent anaerobic digestion and inhibits methane production. In order to nullify the alkaline effect caused by the MW + H2O2 combination, the addition of acid was considered for pH adjustment. H2O2-assisted MW-pretreated sludge in acidic conditions (MW + H2O2 + acid) showed a maximum methane production of 323 mL/g volatile solids (VS) than others during anaerobic biodegradability. A cost analysis of this study reveals that MW + H2O2 + acid was the most economical method with a net profit of 59.90 €/t of sludge. PMID:27026550

  16. Tar remover poisoning

    ... is used to get rid of tar, a dark oily material. This article discusses health problems that ... alertness (unconsciousness) Seizures Staggering Weakness SKIN Burns Irritation Holes in the skin or tissues under the skin

  17. Bioremediation potential of coal-tar-oil-contaminated soil

    The bioremediation of coal tar oil contaminated soil was investigated in 90 day laboratory simulation experiments. The effect of soil moisture, humic acid amendment, and coal tar oil concentration on the rate of disappearance of individual coal tar oil constituents (PAHs and related compounds) was determined by methylene chloride extraction and gas chromatography. Mass balance experiments determined the fate of both the individual 14C-labeled PAHs phenanthrene, pyrene, and benzo(a)pyrene, and the total coal tar oil carbon. Mineralization, volatilization, incorporation into microbial biomass, disappearance of individual coal tar oil constitutents, and the distribution of residual 14C-activity in different soil fractions were measured. The rate of disappearance of coal tar oil constituents increased with increasing soil moisture over the experimental range. Humic acid amendment initially enhanced the rate of disappearance, but decreased the extent of disappearance. The amount of contamination removed decreased at higher coal tar oil concentrations. The practical limit for biodegradation in the system tested appeared to be between 1.0 and 2.5% coal tar oil. Mineralization accounted for 40 to 50% of the applied coal tar oil. Volatilization was a minor pathway of disappearance

  18. Excess sludge and herbaceous plant co-digestion for volatile fatty acids generation improved by protein and cellulose conversion enhancement.

    Zhang, Dong; Fu, Xiang; Jia, Shuting; Dai, Lingling; Wu, Bing; Dai, Xiaohu

    2016-01-01

    Volatile fatty acids (VFA), the substrate for the bio-methane yield, can be generated from excess sludge or herbaceous plant waste during the anaerobic fermentation process. However, due to the high protein content and the low carbon-to-nitrogen (C/N) ratio of excess sludge, the nutrient utilization of excess sludge to generate VFA and bio-methane usually becomes inefficient and uneconomical. In this study, the laboratory findings showed that both the organic conversion and VFA generation from the mixture of excess sludge and herbaceous plant waste (e.g., the tall fescue was used as model), could be significantly enhanced, especially when the C/N ratio was adjusted to 20/1. In order to get more VFA and bio-methane generation, the effects of different thermal pretreatment strategies on the excess sludge and tall fescue co-fermentation were investigated. The study of thermal pretreatment revealed that the maximal VFA generation (585.2 g COD/kg of total solids (TS)) from the mixture of sludge and tall fescue by thermal pretreatment at 100 °C was almost 9.9 and 4.1 times higher than un-pretreated sole sludge and tall fescue, respectively. Then the mechanism of enhanced VFA generation from the mixture by thermal pretreatment was investigated. It was observed that pretreating the mixture of excess sludge and tall fescue at 100 °C caused the greatest hydrolysis and acidification. The produced VFA was applied to generate the bio-methane, and it was showed that the bio-methane produced from the thermal-pretreated (100 °C) mixture was almost 9.6 and 4.9 times as high as un-pretreated sole sludge and tall fescue, respectively. In addition, the detection of enzyme activities showed that the main enzymes related to cellulose, hemicelluloses, lignin degradation, and acid forming were more active when VFA was produced from the thermal-pretreated (100 °C) mixture than other cases. Class Bacteroidia, class β-Proteobateria, α-Proteobateria, and phylum Firmicutes of the reactor

  19. Biodegradable polymers from organic acids by using activated sludge enriched by aerobic periodic feeding.

    Dionisi, Davide; Majone, Mauro; Papa, Viviana; Beccari, Mario

    2004-03-20

    This article describes a new process for the production of biopolymers (polyhydroxyalkanoates, PHAs) based on the aerobic enrichment of activated sludge to obtain mixed cultures able to store PHAs at high rates and yields. Enrichment was obtained through the selective pressure established by feeding the carbon source in a periodic mode (feast and famine regime) in a sequencing batch reactor. A concentrated mixture of acetic, lactic, and propionic acids (overall concentration of 8.5 gCOD L(-1)) was fed every 2 h at 1 day(-1) overall dilution rate. Even at such high organic load (8.5 gCOD L(-1) day(-1)), the selective pressure due to periodic feeding was effective in obtaining a biomass with a storage ability much higher than activated sludges. The immediate biomass response to substrate excess (as determined thorough short-term batch tests) was characterized by a storage rate and yield of 649 mgPHA (as COD) g biomass (as COD)(-1) h(-1) and 0.45 mgPHA (as COD) mg removed substrates (as COD(-1)), respectively. When the substrate excess was present for more than 2 h (long-term batch tests), the storage rate and yield decreased, whereas growth rate and yield significantly increased due to biomass adaptation. A maximum polymer fraction in the biomass was therefore obtained at about 50% (on COD basis). As for the PHA composition, the copolymer poly(beta-hydroxybutyrate/beta-hydroxyvalerate) with 31% of hydroxyvalerate monomer was produced from the substrate mixture. Comparison of the tests with individual and mixed substrates seemed to indicate that, on removing the substrate mixture for copolymer production, propionic acid was fully utilized to produce propionylCoA, whereas the acetylCoA was fully provided by acetic and lactic acid. PMID:14966798

  20. Enhancement of acidic dye biosorption capacity on poly(ethylenimine) grafted anaerobic granular sludge

    Sun, Xue-Fei, E-mail: xfsun06@gmail.com [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Wang, Shu-Guang, E-mail: wsg@sdu.edu.cn [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Cheng, Wen [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Fan, Maohong [School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Tian, Bing-Hui [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Gao, Bao-Yu; Li, Xiao-Ming [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China)

    2011-05-15

    Developing a novel biosorbent with high capacity is crucial to remove dyes from waters in an efficient way. This study demonstrated that porous anaerobic granular sludge could be grafted with polyethylenimine (PEI), which definitely improved the sorption capacity towards Acid Red 18 (AR18) removal. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) study revealed that the PEI modification introduced a large number of amino groups on the surface of sludge, and the amino groups played an important role in the adsorption of dye molecule. Analysis of sorption data using a Boyd plot confirms the film diffusion was the rate-limiting step. The equilibrium data were well fitted Langmuir model, with a maximum AR18 uptake of 520.52 mg/g. Removal of AR18 decreased with the increasing pH and the maximum color removal was observed at pH 2.0. The sorption energy calculated from Dubinin-Radushkevich isotherm was found to be less than 8 for the biosorption of AR 18, which suggested that the biosorption processes of dye molecule onto modified anaerobic granules could be taken place by physical adsorption. Various thermodynamic parameters, such as {Delta}G{sup 0}, {Delta}H{sup 0} and {Delta}S{sup 0}, were also calculated, which indicated that the present system was spontaneous and endothermic process.

  1. Characteristic of wet method of phosphorus recovery from polish sewage sludge ash with nitric acid

    Gorazda Katarzyna

    2016-12-01

    Full Text Available Sewage Sludge Ash (SSA is a concentrated source of phosphorus and can be successfully recycled via a number of different routes. This paper presents research results on phosphorus recovery from differently combusted sewage sludge with the use of nitric acid extraction. Different SSA forms from Polish thermal utilization stations were compared. It was revealed that sewage treatment technology as well as combustion technology influence many physical and chemical parameters of ashes that are crucial for further phosphorus recovery from such waste according to the proposed method. Presented research defines extraction efficiency, characterized extracts composition and verifies the possibility of using SSA as cheaper and alternative sources of phosphorus compounds. Gdynia, Kielce and Kraków SSA have the best properties for the proposed technology of phosphorus recovery with high extraction efficiency greater than 86%. Unsuitable results were obtained for Bydgoszcz, Szczecin Slag and Warszawa SSA. Extraction process for Łódź and Szczecin Dust SSA need to be improved for a higher phosphorus extraction efficiency greater than 80%.

  2. Ammonium-oxidizing bacteria facilitate aerobic degradation of sulfanilic acid in activated sludge.

    Chen, Gang; Ginige, Maneesha P; Kaksonen, Anna H; Cheng, Ka Yu

    2014-01-01

    Sulfanilic acid (SA) is a toxic sulfonated aromatic amine commonly found in anaerobically treated azo dye contaminated effluents. Aerobic acclimatization of SA-degrading mixed microbial culture could lead to co-enrichment of ammonium-oxidizing bacteria (AOB) because of the concomitant release of ammonium from SA oxidation. To what extent the co-enriched AOB would affect SA oxidation at various ammonium concentrations was unclear. Here, a series of batch kinetic experiments were conducted to evaluate the effect of AOB on aerobic SA degradation in an acclimatized activated sludge culture capable of oxidizing SA and ammonium simultaneously. To account for the effect of AOB on SA degradation, allylthiourea was used to inhibit AOB activity in the culture. The results indicated that specific SA degradation rate of the mixed culture was negatively correlated with the initial ammonium concentration (0-93 mM, R²= 0.99). The presence of AOB accelerated SA degradation by reducing the inhibitory effect of ammonium (≥ 10 mM). The Haldane substrate inhibition model was used to correlate substrate concentration (SA and ammonium) and oxygen uptake rate. This study revealed, for the first time, that AOB could facilitate SA degradation at high concentration of ammonium (≥ 10 mM) in an enriched activated sludge culture. PMID:25259503

  3. Final technical report: Commercialization of the Biofine technology for levulinic acid production from paper sludge

    Fitzpatrick, Stephen W.

    2002-04-23

    This project involved a three-year program managed by BioMetics, Inc. (Waltham, MA) to demonstrate the commercial feasibility of Biofine thermochemical process technology for conversion of cellulose-containing wastes or renewable materials into levulinic acid, a versatile platform chemical. The program, commencing in October 1995, involved the design, procurement, construction and operation of a plant utilizing the Biofine process to convert 1 dry ton per day of paper sludge waste. The plant was successfully designed, constructed, and commissioned in 1997. It was operated for a period of one year on paper sludge from a variety of source paper mills to collect data to verify the design for a commercial scale plant. Operational results were obtained for four different feedstock varieties. Stable, continuous operation was achieved for two of the feedstocks. Continuous operation of the plant at demonstration scale provided the opportunity for process optimization, development of operational protocols, operator training and identification of suitable materials of construction for scale up to commercial operation . Separated fiber from municipal waster was also successfully processed. The project team consisted of BioMetics Inc., Great Lakes Chemical Corporation (West Lafayette, IN), and New York State Energy Research and Development Authority (Albany, NY).

  4. Effects of acid/alkaline pretreatment and gamma-ray irradiation on extracellular polymeric substances from sewage sludge

    In order to investigate the mechanism of extracellular polymeric substances (EPS) influencing sludge characteristics, variations of extractable EPS from municipal sewage sludge by acid/alkaline pretreatment and gamma-ray irradiation were studied. The changes in constituents of EPS were analyzed by UV–vis spectra and SEM images. The effects of alkaline pretreatment and gamma-ray irradiation on the functional groups in EPS were investigated by Fourier transform infrared (FTIR) spectrometer. Results showed that the extractable EPS increased clearly with increasing irradiation dose from 0 to 15 kGy. UV–vis spectra indicated that a new absorption band from 240 nm to 300 nm existed in all irradiated samples, apart from acid condition. The results of FTIR spectroscopic analysis indicated that, irradiation influenced major functional groups in EPS, such as protein and polysaccharide, and these effects were clearer under alkaline condition. SEM images provided that after alkaline hydrolysis, gamma-ray irradiation was more effective in resulting in the sludge flocs and cells broken, compared with acid pretreatment (pH 2.50). - Highlights: • Effects of acid/alkaline pretreatment and gamma irradiation on EPS were examined. • Gamma irradiation and alkaline treatment generated remarkable synergistic effects. • The combined application could promote sludge disintegration and solubilization

  5. Treatment of acidic mine water at uranium mine No. 711 by barium chloride-sludge recycle-fractional neutralization process

    The barium chloride-sludge recycle-fractional neutralization process for disposal of acidic mine water at Uranium Mine No. 711 was checked through laboratory and enlarged tests and one-year industrial trial-run. The results showed that the presented technology can meet the requirements of production and environmental protection

  6. The stabilization of tannery sludge and the character of humic acid-like during low temperature pyrolysis.

    Ma, Hongrui; Gao, Mao; Hua, Li; Chao, Hao; Xu, Jing

    2015-11-01

    Tannery sludge contained plenty of organic matter, and the organic substance stability had direct impact on its derived chars' utilization. In this paper, the stabilization of tannery sludge and the variation of humic acid-like (HAL) extracted by different methods were investigated in a magnetic stirring reactor under low temperature pyrolysis of 100-400 °C. Results showed that the aromatic structure of pyrolysis chars increased with the increase of temperature and time. The char contained highly aromatic structure and relatively small dissolved organic matters (DOM) at 300 °C. The similar behaviors appeared in two HAL series by different extraction methods. The N content, H/C value, and aliphatic structures of HAL decreased with the increase of pyrolysis temperature, while the C/N value and aromatic structures increased with the rise of pyrolysis temperature. The composition and functional groups of HAL were similar with the purchased humic acid (HA). The fluorescence spectra revealed that two main peaks were found at Ex/Em = 239/363-368 nm and 283/359-368 nm in each HAL series from raw and 100 °C pyrolysis tannery sludge, representing a protein-like matter. The new peak appeared at Ex/Em = 263-283/388 nm in each HAL series from 200 °C pyrolysis tannery sludge-represented humic acid-like matter. The fluorescence intensity increased strongly compared to the other two peak intensity. Therefore, the humification of organic matter was increased by pyrolyzing. Notably, the HAL from 200 °C pyrolysis tannery sludge contained simple molecular structure, and the polycondensation increased but with a relative lower humification degree compared to soil HAL and purchased HA. Therefore, the sludge needs further oxidation. The humic substance was negligible by direct extraction when the temperature was 300 and 400 °C. PMID:26092361

  7. Extracting Oil From Tar Sands

    Ford, L. B.; Daly, D.

    1984-01-01

    Recovery of oil from tar sands possible by batch process, using steam produced by solar heater. In extraction process, solar heater provides steam for heating solvent boiler. Boiling solvent removes oil from tar sands in Soxhlet extractor.

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

    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

  9. Acid Fermentation Process Combined with Post Denitrification for the Treatment of Primary Sludge and Wastewater with High Strength Nitrate

    Allen Kurniawan

    2016-03-01

    Full Text Available In this study, an anaerobic baffled reactor (ABR, combined with a post denitrification process, was applied to treat primary sludge from a municipal wastewater treatment plant and wastewater with a high concentration of nitrate. The production of volatile fatty acids (VFAs was maximized with a short hydraulic retention time in the acid fermentation of the ABR process, and then the produced VFAs were supplied as an external carbon source for the post denitrification process. The laboratory scale experiment was operated for 160 days to evaluate the VFAs’ production rate, sludge reduction in the ABR type-acid fermentation process, and the specific denitrification rate of the post denitrification process. As results, the overall removal rate of total chemical oxygen demand (TCOD, total suspended solids (TSS, and total nitrogen (TN were found to be 97%, 92%, 73%, respectively, when considering the influent into ABR type-acid fermentation and effluent from post denitrification. We observed the specific VFAs production rate of 0.074 gVFAs/gVSS/day for the ABR type-acid fermentation, and an average specific denitrification rate of 0.166 gNO3−-N/gVSS/day for the post denitrification. Consequently, we observed that a high production of VFAs from a primary sludge, using application of the ABR type acid fermentation process and the produced VFAs were then successfully utilized as an external carbon source for the post denitrification process, with a high removal rate of nitrogen.

  10. Improving volatile fatty acids production by exploiting the residual substrates in post-fermented sludge: Protease catalysis of refractory protein.

    Yin, Bo; Liu, Hongbo; Wang, Yuanyuan; Bai, Jie; Liu, He; Fu, Bo

    2016-03-01

    The real cause to the low yield of volatile fatty acids (VFAs), from inhibition or low biodegradation, is uncertain in sludge anaerobic fermentation. In this study, poor biodegradability of proteins and fast decrease of the indigenous hydrolase activity in the residual post-fermented sludge were found to be the major reasons. With the addition of trypsin or alkaline protease in residual post-fermented sludge after primary alkaline fermentation, degradation efficiency of refractory protein increased by 33.6% and 34.8%, respectively. Accordingly, the VFAs yields were improved by 69.7% and 106.1%, respectively. Furthermore, the activities of added trypsin and alkaline protease could maintain at 13.52 U/mL and 19.11 U/mL in the alkaline fermentation process. This study demonstrated that exploiting the refractory proteins in residual post-fermented sludge by protease addition seems to be a very promising way for improving VFAs yield of conventional alkaline fermentations with waste activated sludge. PMID:26722812

  11. Metal ion complexation properties of fulvic acids extracted from composted sewage sludge as compared to a soil fulvic acid.

    Esteves da Silva, Joaquim C G; Oliveira, César J S

    2002-07-01

    Complexation properties of an anthropogenic fulvic acid (FA) extracted from a composted sewage sludge (csFA) for Cu(II), Pb(II) and Cd(II) were studied at pH=6 and at a concentration of 25 mg L(-1). For the case of Cu(II), a particular analysis of the complexation phenomena was done at pH values of 3, 4, 5 and 6 and at aqueous FA concentrations of 25, 50 and 100 mg L(-1) by synchronous excitation molecular fluorescence spectroscopy (SyF). Potentiometric titrimetry with Cu(II), Pb(II), Cd(II) and H+ ion-selective electrodes and acid-base conductimetric titrations were used to obtain experimental information about the acid properties and complexation phenomena. A comparison of the results obtained for csFA with a natural soil FA (sFA) was made. Differences have been detected in the structural composition of the two samples and in the structure of the binding sites. In the csFA, binding site structures containing nitrogen probably play an important role in the complexation, besides oxygen containing structures. Complexation by sFA is mainly due to carboxylic and phenolic structures. Nevertheless, this work shows that csFA have macroscopic complexation properties (magnitude of the conditional stability constant and binding sites concentration) somewhat similar to the natural sFA samples. PMID:12188141

  12. Production of bio diesel from sludge palm oil by esterification using p-toluenesulfonic acid

    Full text: Sludge palm oil (SPO) is an attractive feedstock and a significant raw material for bio diesel production. The use of SPO as feedstock for bio diesel production requires additional pretreatment step to transesterification process, which is an esterification process. The most commonly preferred catalysts used in this process are sulfuric, sulphonic, hydrochloric and P-toluenesulfonic acid (PTSA). In this study bio diesel fuel was produced from SPO using PTSA as acid catalyst in different dosages in presence of alcohol to convert free fatty acid (FFA) to fatty acid methyl ester (FAME). Batch esterification process of SPO was carried out to study the influence of PTSA dosage (0.25-10 % wt/wt), molar ratio of methanol to SPO (6:1-20:1), temperature (40-80 degree Celsius), reaction time (30-120 min). The effects of those parameters on FFA content, yield of treated SPO and conversion of FFA to FAME were monitored. The study showed that the FFA content of SPO reduced from 22 % to less than 0.15 % using ratio of 0.5, 0.75, 1, 1.5, and 2 % wt/wt PTSA to SPO. After esterification process dosage of PTSA at 0.75 % wt/wt shows the highest conversion of FFA to FAME as well as yield of treated SPO. The optimum condition for batch esterification process was 10:1 molar ratio, temperature 60 degree Celsius and 60 minutes reaction time. The highest yield of bio diesel after transesterification process was 76.62 % with 0.06 % FFA and 93 % ester content. (author)

  13. Application of sewage sludge for corn cultivation on a tropical acid soil

    Malaysia produces about 5x106 m3 of domestic sewage sludge per year (wet basis), and this is expected to increase to 7x106 m3 by the year 2020. Thus, there is pressure to develop beneficial means of utilizing this waste. Although domestic in origin, it can have high concentrations of Cu and Zn. A field experiment was established to investigate the utility of applying sludge to agricultural land. The soil at the experimental site is well drained and classified as clayey kaolinitic, isohyperthermic Typic Paleudult, pH 4.7, 0.06% N, and 0.97% organic C. The treatments were: control, inorganic N fertilizer (ammonium sulphate) at 140 kg N/ha, and irradiated (IR) and nonirradiated (NIR) sludge applied at rates equivalent to 0, 150, 300, 450 and 600% of the recommended fertilizer N rate of 140 kg N/ha to the first corn cycle. No sludge was applied during the second corn cycle in order to observe any residual effects of the previously applied sludge. In the third, fourth and fifth corn cycles, the sludge rates were reduced to 100, 200, 300, and 400% of the recommended fertilizer-N rate. The plot size was 4x6 m, and the treatments had four replications. To quantify the availability of sludge N, the indirect 15N-dilution technique was used. Twenty kg 15N/ha (10% of a.e.) were added to the control and sludge-treatment plots in the first crop cycle. However, the method failed, as sludge-derived N in the crop could not be calculated. This may have been because the added 15N was not in equilibrium with soil N when the sludge was added, and the amount was large enough to cause an interaction with the sludge. With the fifth crop, the 15N technique was applied again, at 5 kg15N/ha (20% a.e.) in the all-sludge treatments and 140 kg15N/ha at 3% a.e. in the inorganic N-fertilizer treatment. No significant differences in dry matter yields were found among the various sludge rates, neither were there differences between the IR and NIR sludges due to high variability. In general, it

  14. Investigation into the use of cement kiln dust in high density sludge (HDS) treatment of acid mine water.

    Mackie, Allison L; Walsh, Margaret E

    2015-11-15

    The purpose of this study was to investigate the potential to replace lime with cement kiln dust (CKD) in high density sludge (HDS) treatment of acid mine drainage (AMD). The bench-scale study used two water samples: AMD sampled from a lead-zinc mine with high concentrations of iron (Fe), zinc (Zn), and arsenic (As) (Fe/Zn-AMD) and a synthetic AMD solution (Syn-AMD) spiked with ferric sulfate (Fe2(SO4)3). Arsenic was found to be significantly reduced with CKD-HDS treatment of Fe/Zn-AMD compared to lime-HDS treatment, to concentrations below the stringent mine effluent discharge regulation of 0.10 mg As/L (i.e., 0.04 ± 0.02 mg/L). Both CKD- and lime-HDS treatment of the two AMD samples resulted in settled water Fe concentrations above the stringent discharge guideline of 0.3 mg Fe/L. CKD addition in the HDS process also resulted in high settled water turbidity, above typical discharge guidelines of 15 mg TSS/L. CKD-HDS treatment was found to result in significantly improved settled solids (i.e., sludge) quality compared to that generated in the lime-HDS process. HDS treatment with CKD resulted in 25-88% lower sludge volume indices, 2 to 9 times higher % wet solids, and 10 to 20 times higher % dry solids compared to lime addition. XRD and XPS testing indicated that CKD-HDS sludge consisted of mainly CaCO3 and SiO2 with Fe(3+) precipitates attached at particle surfaces. XRD and XPS testing of the lime-HDS generated sludge showed that it consisted of non-crystalline Fe oxides typical of sludge formed from precipitates with a high water concentration. Increased sedimentation rates were also found for CKD (1.3 cm/s) compared to lime (0.3 cm/s). The increased solids loading with CKD addition compared to lime addition in the HDS process was suggested to both promote surface complexation of metal precipitates with insoluble CKD particles and increase compression effects during Type IV sedimentation. These mechanisms collectively contributed to the reduced water content of

  15. Compositional and functional features of humic acid-like fractions from vermicomposting of sewage sludge and cow dung.

    Li, Xiaowei; Xing, Meiyan; Yang, Jian; Huang, Zhidong

    2011-01-30

    The chemical changes occurring in five different substrates of sewage sludge spiked with different proportions of cow dung after vermicomposting with Eisenia foetida for 90 days were investigated. Their humic acid-like (HAL) fractions were isolated to determine the elemental and functional composition, and structural and functional characteristics using ultraviolet/visible, Fourier transform infrared (FT-IR) and fluorescence spectroscopies and scanning electron microscopy. After vermicomposting, the total organic C and C/N ratio decreased, and the total extractable C and humic acid (HA) C increased in all substrates. In the HAL fractions, the C and H contents, C/N and C/O and aliphatic structures, proteinaceous components and carbohydrates decreased, while the O and N and acidic functional group contents and C/H ratio, aromaticity and polycondensation structures increased. Further, the results suggest that the addition of cow dung to sewage sludge could improve the quality of organic matter humification of the substrates. The structures of HAL fractions in vermicomposts resembled those typical of soil HA, especially the vermicompost of cow dung alone. Scanning electron microscopy showed the microstructure of HAL fraction in final product became close-grained and lumpy. Overall results indicate that vermicomposting was an efficient technology for promoting organic matter (OM) humification in sewage sludge and cow dung alone, as well as in mixtures of both materials, improving their quality and environmental safety as a soil OM resource for utilization as soil amendments. PMID:21030148

  16. Effects of acid/alkaline pretreatment and gamma-ray irradiation on extracellular polymeric substances from sewage sludge

    Xie, Shuibo; Wu, Yuqi; Wang, Wentao; Wang, Jingsong; Luo, Zhiping; Li, Shiyou

    2014-04-01

    In order to investigate the mechanism of extracellular polymeric substances (EPS) influencing sludge characteristics, variations of extractable EPS from municipal sewage sludge by acid/alkaline pretreatment and gamma-ray irradiation were studied. The changes in constituents of EPS were analyzed by UV-vis spectra and SEM images. The effects of alkaline pretreatment and gamma-ray irradiation on the functional groups in EPS were investigated by Fourier transform infrared (FTIR) spectrometer. Results showed that the extractable EPS increased clearly with increasing irradiation dose from 0 to 15 kGy. UV-vis spectra indicated that a new absorption band from 240 nm to 300 nm existed in all irradiated samples, apart from acid condition. The results of FTIR spectroscopic analysis indicated that, irradiation influenced major functional groups in EPS, such as protein and polysaccharide, and these effects were clearer under alkaline condition. SEM images provided that after alkaline hydrolysis, gamma-ray irradiation was more effective in resulting in the sludge flocs and cells broken, compared with acid pretreatment (pH 2.50).

  17. Compositional and functional features of humic acid-like fractions from vermicomposting of sewage sludge and cow dung

    The chemical changes occurring in five different substrates of sewage sludge spiked with different proportions of cow dung after vermicomposting with Eisenia foetida for 90 days were investigated. Their humic acid-like (HAL) fractions were isolated to determine the elemental and functional composition, and structural and functional characteristics using ultraviolet/visible, Fourier transform infrared (FT-IR) and fluorescence spectroscopies and scanning electron microscopy. After vermicomposting, the total organic C and C/N ratio decreased, and the total extractable C and humic acid (HA) C increased in all substrates. In the HAL fractions, the C and H contents, C/N and C/O and aliphatic structures, proteinaceous components and carbohydrates decreased, while the O and N and acidic functional group contents and C/H ratio, aromaticity and polycondensation structures increased. Further, the results suggest that the addition of cow dung to sewage sludge could improve the quality of organic matter humification of the substrates. The structures of HAL fractions in vermicomposts resembled those typical of soil HA, especially the vermicompost of cow dung alone. Scanning electron microscopy showed the microstructure of HAL fraction in final product became close-grained and lumpy. Overall results indicate that vermicomposting was an efficient technology for promoting organic matter (OM) humification in sewage sludge and cow dung alone, as well as in mixtures of both materials, improving their quality and environmental safety as a soil OM resource for utilization as soil amendments.

  18. Compositional and functional features of humic acid-like fractions from vermicomposting of sewage sludge and cow dung

    Li Xiaowei [State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Xing Meiyan, E-mail: xmy5000@163.com [State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Yang Jian; Huang Zhidong [State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China)

    2011-01-30

    The chemical changes occurring in five different substrates of sewage sludge spiked with different proportions of cow dung after vermicomposting with Eisenia foetida for 90 days were investigated. Their humic acid-like (HAL) fractions were isolated to determine the elemental and functional composition, and structural and functional characteristics using ultraviolet/visible, Fourier transform infrared (FT-IR) and fluorescence spectroscopies and scanning electron microscopy. After vermicomposting, the total organic C and C/N ratio decreased, and the total extractable C and humic acid (HA) C increased in all substrates. In the HAL fractions, the C and H contents, C/N and C/O and aliphatic structures, proteinaceous components and carbohydrates decreased, while the O and N and acidic functional group contents and C/H ratio, aromaticity and polycondensation structures increased. Further, the results suggest that the addition of cow dung to sewage sludge could improve the quality of organic matter humification of the substrates. The structures of HAL fractions in vermicomposts resembled those typical of soil HA, especially the vermicompost of cow dung alone. Scanning electron microscopy showed the microstructure of HAL fraction in final product became close-grained and lumpy. Overall results indicate that vermicomposting was an efficient technology for promoting organic matter (OM) humification in sewage sludge and cow dung alone, as well as in mixtures of both materials, improving their quality and environmental safety as a soil OM resource for utilization as soil amendments.

  19. Urban energy mining from sewage sludge.

    Kwon, E E; Yi, H; Kwon, H H

    2013-01-01

    This work showed that sewage sludge could be a strong candidate for biodiesel production. High lipid content (18-20%) with C(16-18)-carbon range was experimentally identified and measured. These lipids from sewage sludge were converted into biodiesel via the transesterification reaction with MgO-CaO/Al(2)O(3) derived from magnesium slag, and biodiesel conversion was ~98%. The experimental work enabled explaining that temperature is the main driving force for the transesterification reaction, which can be enhanced in the presence of CO(2). This also enables combination of esterification of free fatty acids and transesterification of triglycerides into a single process within 1 min in the temperature range of 350-500°C. Sewage sludge residue after extracting lipids was also a good feedstock for recovering energy via thermo-chemical processes. The impact of CO(2) co-feed on the pyrolysis/gasification process of SS residue was also investigated in this work. The CO(2) injected into the thermo-chemical process remarkably increased the generation of CO by a factor of 2. Moreover, the introduction of CO(2) into the pyrolysis/gasification process enabled reducing condensable hydrocarbons (tar) by expediting cracking; thus, utilizing CO(2) as chemical feedstock for the gasification process not only leads to higher thermal efficiency but also has environmental benefits. PMID:23017593

  20. Methane Production from Rice Straw Hydrolysate Treated with Dilute Acid by Anaerobic Granular Sludge.

    Cheng, Jing-Rong; Liu, Xue-Ming; Chen, Zhi-Yi

    2016-01-01

    The traditional anaerobic digestion process of straw to biogas faces bottlenecks of long anaerobic digestion time, low digestion rate, less gas production, etc., while straw hydrolysate has the potential to overcome these drawbacks. In this study, the dilute sulphuric acid-treated hydrolysate of rice straw (DSARSH) containing high sulfate was firstly proved to be a feasible substrate for methane production under mesophilic digestion by granular sludge within a short digestion time. Batch anaerobic digestion process was operated under different initial chemical oxygen demand (COD) values at temperature of 37 °C with the pH of 8.5. Among the initial COD values ranging from 3000 to 11,000 mg/L, 5000 mg/L was proved to be the most appropriate considering high COD removal efficiency (94.17 ± 1.67 %), CH4 content (65.52 ± 3.12 %), and CH4 yield (0.346 ± 0.008 LCH4/g COD removed) within 120 h. Furthermore, when the studied system operated at the initial COD of 5000 mg/L, the sulfate removal ratio could reach 56.28 %. PMID:26378012

  1. Heavy metal removal from sewage sludge ash by thermochemical treatment with gaseous hydrochloric acid.

    Vogel, Christian; Adam, Christian

    2011-09-01

    Sewage sludge ash (SSA) is a suitable raw material for fertilizers due to its high phosphorus (P) content. However, heavy metals must be removed before agricultural application and P should be transferred into a bioavailable form. The utilization of gaseous hydrochloric acid for thermochemical heavy metal removal from SSA at approximately 1000 °C was investigated and compared to the utilization of alkaline earth metal chlorides. The heavy metal removal efficiency increased as expected with higher gas concentration, longer retention time and higher temperature. Equivalent heavy metal removal efficiency were achieved with these different Cl-donors under comparable conditions (150 g Cl/kg SSA, 1000 °C). In contrast, the bioavailability of the P-bearing compounds present in the SSA after thermal treatment with gaseous HCl was not as good as the bioavailability of the P-bearing compounds formed by the utilization of magnesium chloride. This disadvantage was overcome by mixing MgCO(3) as an Mg-donor to the SSA before thermochemical treatment with the gaseous Cl-donor. A test series under systematic variation of the operational parameters showed that copper removal is more depending on the retention time than the removal of zinc. Zn-removal was declined by a decreasing ratio of the partial pressures of ZnCl(2) and water. PMID:21819089

  2. Pb(II), Cr(VI) and atrazine sorption behavior on sludge-derived biochar: role of humic acids.

    Zhou, Fengsa; Wang, Hong; Fang, Sheng'en; Zhang, Weihua; Qiu, Rongliang

    2015-10-01

    Pyrolyzing municipal wastewater treatment sludge into biochar can be a promising sludge disposal approach, especially as the produced sludge-derived biochar (SDBC) is found to be an excellent sorbent for heavy metals and atrazine. The aim of this study was to investigate how and why the coexisting humic acids influence the sorption capacity, kinetic, and binding of these contaminants on SDBC surface. Results showed humic acids enhanced Pb(II)/Cr(VI) sorption binding, and increased the corresponding Pb(II) Langmuir sorption capacity at pH 5.0 from 197 to 233 μmol g(-1), and from 688 to 738 μmol g(-1) for Cr(VI) at pH 2.0. It can be mainly attributed to the sorbed humic acids, whose active functional groups can offer the additional sites to form stronger inner-sphere complexes with Pb(2+), and supply more reducing agent to facilitate the transformation of Cr(VI) to Cr(III). However, humic acids reduced the atrazine adsorption Freundlich constant from 1.085 to 0.616 μmol g(-1). The pore blockage, confirmed by the decreased BET-specific surface area, as well as the more hydrophilic surface with more sorbed water molecules may be the main reasons for that suppression. Therefore, the coexisting humic acids may affect heavy metal stabilization or pesticide immobilization during SDBC application to contaminated water or soils, and its role thus should be considered especially when organic residues are also added significantly to increase the humic acid content there. PMID:26062468

  3. Nutrient leaching potential following application of papermill lime-sludge to an acidic clay soil

    S. C. Vettorazzo

    2001-09-01

    Full Text Available This experiment was carried out under greenhouse conditions with soil pots during 210 days, to evaluate the effect of calcitic papermill lime-sludge application (at the rates 0, 773, 1.547, and 2.320 mg kg-1 or respective equivalents to control, 2, 4, and 6 t ha-1, on chemical composition of soil leachate and its effects on eucalypt growth and yield. Highest soil leachate pH, SO4, and Na concentrations occurred in the 4 and 6 t ha-1 treatments. Soil leachate nitrate concentrations decreased with increasing lime-sludge rate. Soil leachate phosphate remained low (below the detection limit in all treatments until 120 days, while the concentration increased in the lime-sludge treatments at 210 days (last sampling in about 600 mg L-1. Lime-sludge decreased leachate Mg concentration, but had no significant effect among rates. Soil leachate Ca, K, B, Cu, Fe, and Zn did not change significantly for any lime-sludge application rates. The maximum NO3, Ca, Mg, K, and Na concentrations in the soil leachate occurred at 60 days after lime-sludge application (leaching equivalent to 1 pore volume, but for pH and SO4, the maximum occurred at 210 days (leaching equivalent to 4 pore volumes. Lime-sludge application decreased the concentration of exchangeable Al in the soil. Plant diameter growth and dry matter yield were increased with increasing lime-sludge rate. Beneficial effects on mineral nutrition (P, K, Ca, B, and Zn of eucalypts were also obtained by the application of 4 and 6 t ha-1 of lime-sludge.

  4. Availability of Cu and Zn in an acidic sludge-amended soil as affected by zeolite application and liming

    Antoniadis, Vasileios; Dimirkou, Anthoula [Thessaly Univ., Volos (Greece). Dept. of Agriculture, Crop Production and Rural Environment; Damalidis, Konstantinos [Democritus Univ. of Thrace, Orestiada (Greece). Dept. of Agricultural Development

    2012-03-15

    Acidic soils exhibit high trace element availability compared to neutral pH soils, and thus, when trace metals are added (e.g. due to sewage sludge application), measures should be taken to reduce their mobility. In this experiment, we tested two such methods, liming and zeolite addition. The aim was to measure the availability, in ryegrass (Lolium perenne L.), of heavy metals (Cu and Zn) added to soil with sewage sludge in both acidic and limed soil. Thus, in this pot experiment, we used a soil at two pH values (original soil at pH 3.56 and limed to 6.5), two rates of sewage sludge (0 and 50 Mg ha{sup -1}) and three rates of zeolite (0, 2 and 5 Mg ha{sup -1}, referred to as Z-0, Z-1 and Z-2, respectively). We found that metal concentrations in plant decreased significantly with liming but zeolite did not further reduce metal levels. In metal extractions with DTPA, zeolite additions reduced metal concentrations. In the second sampling time (on day 100), metal levels were significantly reduced at Z-0 and Z-1 compared to day 50, but at Z-2, metals were either only slightly reduced or even unchanged. We concluded that zeolite hindered metals from being strongly and irreversibly bound onto soil colloids. Zeolite at Z-2 kept metal availability relatively high over time, while metal availability at Z-0 and Z-1 was being reduced due to liming. (orig.)

  5. Acid extraction of molybdenum, nickel and cobalt from mineral sludge generated by rainfall water at a metal recycling plant.

    Vemic, M; Bordas, F; Guibaud, G; Comte, S; Joussein, E; Lens, P N L; Van Hullebusch, E D

    2016-01-01

    This study investigated the leaching yields of Mo, Ni and Co from a mineral sludge of a metal recycling plant generated by rainfalls. The investigated mineral sludge had a complex heterogeneous composition, consisting of particles of settled soil combined with metal-bearing particles (produced by catalysts, metallic oxides and battery recycling). The leaching potential of different leaching reagents (stand-alone strong acids (HNO3 (68%), H2SO4 (98%) and HCl (36%)) and acid mixtures (aqua regia (nitric + hydrochloric (1:3)), nitric + sulphuric (1:1) and nitric + sulphuric + hydrochloric (2:1:1)) was investigated at changing operational parameters (solid-liquid (S/L) ratio, leaching time and temperature), in order to select the leaching reagent which achieves the highest metal leaching yields. Sulphuric acid (98% H2SO4) was found to be the leachant with the highest metal leaching potential. The optimal leaching conditions were a three-stage successive leaching at 80 °C with a leaching time of 2 h and S/L ratio of 0.25 g L(-1). Under these conditions, the achieved mineral sludge sample leaching yields were 85.5%, 40.5% and 93.8% for Mo, Ni and Co, respectively. The higher metal leaching potential of H2SO4 in comparison with the other strong acids/acid mixtures is attributed to the fact that H2SO4 is a diacidic compound, thus it has more H(+) ions, resulting in its stronger oxidizing power and corrosiveness. PMID:26369315

  6. Hygienisation and Nutrient Conservation of Sewage Sludge or Cattle Manure by Lactic Acid Fermentation

    Scheinemann, Hendrik A.; Dittmar, Katja; Stöckel, Frank S.; Müller, Hermann; Krüger, Monika E.

    2015-01-01

    Manure from animal farms and sewage sludge contain pathogens and opportunistic organisms in various concentrations depending on the health of the herds and human sources. Other than for the presence of pathogens, these waste substances are excellent nutrient sources and constitute a preferred organic fertilizer. However, because of the pathogens, the risks of infection of animals or humans increase with the indiscriminate use of manure, especially liquid manure or sludge, for agriculture. Thi...

  7. Diversity of Anaerobic Microorganisms Involved in Long-Chain Fatty Acid Degradation in Methanogenic Sludges as Revealed by RNA-Based Stable Isotope Probing▿

    Hatamoto, Masashi; IMACHI, HIROYUKI; Yashiro, Yuto; Ohashi, Akiyoshi; Harada, Hideki

    2007-01-01

    Long-chain fatty acid (LCFA) degradation is a key step in methanogenic treatment of wastes/wastewaters containing high concentrations of lipids. However, despite the importance of LCFA-degrading bacteria, their natural diversity is little explored due to the limited availability of isolate information and the lack of appropriate molecular markers. We therefore investigated these microbes by using RNA-based stable isotope probing. We incubated four methanogenic sludges (mesophilic sludges MP a...

  8. Prediction of tar ball formation

    Khelifa, A.; Gamble, L. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Division, Environmental Technology Centre, Science and Technology Branch

    2006-07-01

    The presence of small tar balls ranging in size from less than a millimetre to 60 centimetres have been observed during cleanup assessment operations following accidental oil spills on water. The tar balls are composed of heavy oil residues and suspended particulate matter (SPM) from the water column. They can be found on shorelines, settled on the seafloor and floating at or near the water surface. Their abundance on the shorelines varies from site to site and depends on the conditions of the spill and mixing conditions. Aggregation between SPM and micro-sized oil droplets occurs naturally in coastal waters and enhances the dispersion of spilled oil. Although tar balls are among the important end states of spilled oil in the marine environment, no model exists to estimate the percentage of the spilled oil that becomes tar balls. This paper offered some insight into the modeling of tar ball formation. Current modeling understanding of oil-SPM aggregate formation was used to predict tar ball formation. The formation of oil droplets was examined with respect to a range of conditions under which the formation of large droplets is expected. The role of aggregation was then presented to demonstrate the effects of concentration and type of SPM on the buoyancy of tar balls. Good agreement was found between modeling results and field data reported in the literature regarding the size and density of tar balls. Oil viscosity and mixing energy were found to be the main factors controlling the formation of tar balls. The aggregation of tar balls with SPM and shoreline material results in significant increases or decreases in density, depending on the type and concentration of SPM. 42 refs., 2 tabs., 6 figs.

  9. Recovery of molybdenum, nickel and cobalt by precipitation from the acidic leachate of a mineral sludge.

    Vemic, M; Bordas, F; Comte, S; Guibaud, G; Lens, P N L; van Hullebusch, E D

    2016-09-01

    The objective of this study was to investigate the recovery potential of molybdenum (Mo), nickel (Ni) and cobalt (Co) from synthetic and real acidic leachate of a mineral sludge from a metal recycling plant by sulfide precipitation. The operational parameters (metal sulfide (M/S) ratio 0.1-1, agitation speed 0-100 rpm, contact time 15-120 min and pH 1-5) were optimized in batch conditions on synthetic metal leachate (0.5 M HNO3, Mo = 101.6 mg L(-1), Ni = 70.8 mg L(-1), Co = 27.1 mg L(-1)) with a 0.1 M Na2S solution. Additionally, recovery of the target metals was theoretically simulated with a chemical equilibrium model (Visual MINTEQ 3.0). The optimized Na2S precipitation of metals from the synthetic leachate resulted in the potential selective recovery of Mo at pH 1 (98% by modeling, 95% experimental), after simultaneous precipitation of Ni and Co as sulfide at pH 4 (100% by modeling, 98% experimental). Metal precipitation from the real leachate (18 M H2SO4, Mo = 10,160 mg L(-1), Ni = 7,080 mg L(-1), Co = 2,710 mg L(-1)) was performed with 1 M Na2S, and resulted in a maximal Mo recovery at pH 2 (50%), while maximal recoveries of Ni and Co were observed at pH 4 (56% and 60%, respectively). Real leachate gave a lower metals recovery efficiency compared with synthetic leachate, which can be attributed to changes in the pH, nature of leachant, co-precipitation of Zn and competition for S(2-) ions. PMID:26824137

  10. Production of medium-chain-length polyhydroxyalkanoates by activated sludge enriched under periodic feeding with nonanoic acid.

    Lee, Sun Hee; Kim, Jae Hee; Mishra, Debaraj; Ni, Yu-Yang; Rhee, Young Ha

    2011-05-01

    The potential use of activated sludge for the production of medium-chain-length polyhydroxyalkanoates (MCL-PHAs) was investigated. The enrichment of bacterial populations capable of producing MCL-PHAs was achieved by periodic feeding with nonanoic acid in a sequencing batch reactor (SBR). Denaturing gradient gel electrophoresis analysis revealed Pseudomonas aeruginosa strains to be predominant in the bacterial community during the SBR process. The composition of PHA synthesized by the enriched biomass from nonanoic acid consisted of a large concentration (>89 mol%) of MCL monomer units and a small amount of short-chain-length monomer units. Under fed-batch fermentation with continuous feeding of nonanoic acid at a flow rate of 0.225 g/L/h and a C/N ratio of 40, a maximum PHA content of 48.6% dry cell weight and a conversion yield (Y(p/s)) of 0.94 g/g were achieved. These results indicate that MCL-PHA production by activated sludge is a promising alternative to typical pure culture approaches. PMID:21463934

  11. Adsorption of acid and basic dyes by sludge-based activated carbon:Isotherm and kinetic studies

    李鑫; 王广智; 李伟光; 王萍; 宿程远

    2015-01-01

    A batch experiment was conducted to investigate the adsorption of an acid dye (Acid Orange 51) and a basic dye (Safranine) from aqueous solutions by the sludge-based activated carbon (SBAC). The results show that the adsorption of Acid Orange 51 decreases at high pH values, whereas the uptake of Safranine is higher in neutral and alkaline solutions than that in acidic conditions. The adsorption time needed for Safranine to reach equilibrium is shorter than that for Acid Orange 51. The uptakes of the dyes both increase with temperature increasing, indicating that the adsorption process of the dyes onto SBAC is endothermic. The equilibrium data of the dyes are both best represented by the Redlich−Peterson model. At 25 °C, the maximum adsorption capacities of SBAC for Acid Orange 51 and Safranine are 248.70 mg/g and 525.84 mg/g, respectively. The Elovich model is found to best describe the adsorption process of both dyes, indicating that the rate-limiting step involves the chemisorption. It can be concluded that SBAC is a promising material for the removal of Acid Orange 51 and Safranine from aqueous solutions.

  12. Acetic acid recovery from a hybrid biological-hydrothermal treatment process of sewage sludge - a pilot plant study.

    Andrews, J; Dare, P; Estcourt, G; Gapes, D; Lei, R; McDonald, B; Wijaya, N

    2015-01-01

    A two-stage process consisting of anaerobic fermentation followed by sub-critical wet oxidation was used to generate acetic acid from sewage sludge at pilot scale. Volatile fatty acids, dominated by propionic acid, were produced over 4-6 days in the 2,000 L fermentation reactor, which also achieved 31% solids reduction. Approximately 96% of the carbon was retained in solution over the fermentation stage. Using a 200 L wet oxidation reactor operating in batch mode, the second stage achieved 98% volatile suspended solids (VSS) destruction and 67% total chemical oxygen demand (tCOD) destruction. Acetic acid produced in this stage was recalcitrant to further degradation and was retained in solution. The gross yield from VSS was 16% for acetic acid and 21% for volatile fatty acids across the process, higher than reported yields for wet oxidation alone. The pilot plant results showed that 72% of the incoming phosphorus was retained in the solids, 94% of the nitrogen became concentrated in solution and 41% of the carbon was converted to a soluble state, in a more degradable form. Acetic acid produced from the process has the potential to be used to offset ethanol requirements in biological nutrient removal plants. PMID:25768220

  13. Short-chain fatty acids production and microbial community in sludge alkaline fermentation: Long-term effect of temperature.

    Yuan, Yue; Liu, Ye; Li, Baikun; Wang, Bo; Wang, Shuying; Peng, Yongzhen

    2016-07-01

    Sludge alkaline fermentation has been reported to achieve efficient short-chain fatty acids (SCFAs) production. Temperature played important role in further improved SCFAs production. Long-term SCFAs production from sludge alkaline fermentation was compared between mesotherm (30±2°C) and microtherm (15±2°C). The study of 90days showed that mesotherm led to 2.2-folds production of SCFAs as microtherm and enhanced the production of acetic acid as major component of SCFAs. Soluble protein and carbohydrate at mesotherm was 2.63-folds as that at microtherm due to higher activities of protease and α-glucosidase, guaranteeing efficient substrates to produce SCFAs. Illumina MiSeq sequencing revealed that microtherm increased the abundance of Corynebacterium, Alkaliflexus, Pseudomonas and Guggenheimella, capable of enhancing hydrolysis. Hydrolytic bacteria, i.e. Alcaligenes, Anaerolinea and Ottowia, were enriched at mesotherm. Meanwhile, acidogenic bacteria showed higher abundance at mesotherm than microtherm. Therefore, enrichment of functional bacteria and higher microbial activities resulted in the improved SCFAs at mesotherm. PMID:27060243

  14. Identification of a novel HIV-1 TAR RNA bulge binding protein.

    B. Baker; Muckenthaler, M; Vives, E.; Blanchard, A.; Braddock, M; Nacken, W.; Kingsman, A J; Kingsman, S M

    1994-01-01

    The Tat protein binds to TAR RNA to stimulate the expression of the human immunodeficiency virus type 1 (HIV-1) genome. Tat is an 86 amino acid protein that contains a short region of basic residues (aa49-aa57) that are required for RNA binding and TAR is a 59 nucleotide stem-loop with a tripyrimidine bulge in the upper stem. TAR is located at the 5' end of all viral RNAs. In vitro, Tat specifically interacts with TAR by recognising the sequence of the bulge and upper stem, with no requiremen...

  15. Validation and application of an analytical method for the determination of selected acidic pharmaceuticals and estrogenic hormones in wastewater and sludge.

    Zhang, Mengtao; Mao, Qianhui; Feng, Jingwei; Yuan, Shoujun; Wang, Qiquan; Huang, Deying; Zhang, Jibiao

    2016-09-18

    This study was undertaken to develop an extraction method for seven acidic pharmaceuticals and five steroidal estrogens from wastewater, treated wastewater and sludge samples. The temperature and time of sample derivatization using N,O-bis(trimethylsilyl)trifluoroacetamide was optimized. Our results show that pretreatment combined with solid phase extraction (SPE) for wastewater samples (using an ENVI-C18 cartridge) and liquid-solid extraction combined with SPE (using an HLB cartridge) for sludge samples increased the analytical efficiency for acidic pharmaceuticals and estrogenic hormones using gas chromatography-mass spectrometry (GC-MS). The derivatization conditions were optimized at 40°C for 2 h. In addition, the derivatized samples were stable at ambient temperature. The new method was validated and applied to the analysis of real wastewater and discharged sludge samples from a local wastewater treatment plant. Except for 17α-ethinylestradiol, all acidic pharmaceuticals and estrogens were detected in the influent, effluent and discharged sludge samples. The concentrations of these compounds were particularly high in the discharged sludge samples. PMID:27314419

  16. Increase in complexation ability of humic acids with the addition of ligneous bulking agents during sewage sludge composting.

    Xiong, Xiong; Yan-Xia, Li; Ming, Yang; Feng-Song, Zhang; Wei, Li

    2010-12-01

    Wood sawdust and maize straw were selected to co-compost sewage sludge to investigate the effects of organic bulking agents on the formation and molecular transformation of humic substances. The results showed that composting process increased humic acids (HA) while decreased fulvic acids (FA), and the wood sawdust and maize straw promoted the formation of HA by 25.6% and 16.1%, respectively. Results from fluorescence titration demonstrated that organic bulking agents also increased the binding ability of HA with the heavy metal ions, Cu(II) and Cd(II), but had little influence on that of FA. These findings indicate that organic materials especially wood sawdust may be used as bulking agents to reduce the mobility and bioavailability of toxic metals in solid waste composts. PMID:20724147

  17. [Effect of various kinds of tar and tar concentrations on anthralin erythema].

    Wemmer, U; Schulze, H J; Mahrle, G; Steigleder, G K

    1986-06-15

    The effect of tar on anthralin-induced erythema was epicutaneously tested in ten patients. 3%, 5%, or 10% crude coal tar or coal tar solution was added to vaseline containing anthralin. A 5% or 10% tar preparation significantly suppressed the anthralin erythema induced by 0.5 to 1.0% anthralin having been applied for 24 hrs. In these concentrations, coal tar solution was at least as effective as coal tar itself. PMID:3751210

  18. Polycyclic Aromatic Hydrocarbon Affects Acetic Acid Production during Anaerobic Fermentation of Waste Activated Sludge by Altering Activity and Viability of Acetogen.

    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

  19. Topical tar: Back to the future

    Paghdal, K.V.; Schwartz, R.A. [University of Medicine & Dentistry of New Jersey, Newark, NJ (United States)

    2009-08-15

    The use of medicinal tar for dermatologic disorders dates back to the ancient times. Although coal tar is utilized more frequently in modern dermatology, wood tars have also been widely employed. Tar is used mainly in the treatment of chronic stable plaque psoriasis, scalp psoriasis, atopic dermatitis, and seborrheic dermatitis, either alone or in combination therapy with other medications, phototherapy, or both. Many modifications have been made to tar preparations to increase their acceptability, as some dislike its odor, messy application, and staining of clothing. One should consider a tried and true treatment with tar that has led to clearing of lesions and prolonged remission times. Occupational studies have demonstrated the carcinogenicity of tar; however, epidemiologic studies do not confirm similar outcomes when used topically. This article will review the pharmacology, formulations, efficacy, and adverse effects of crude coal tar and other tars in the treatment of selected dermatologic conditions.

  20. Improving volatile fatty acid yield from sludge anaerobic fermentation through self-forming dynamic membrane separation.

    Liu, Hongbo; Wang, Yuanyuan; Yin, Bo; Zhu, Yanfang; Fu, Bo; Liu, He

    2016-10-01

    Self-forming dynamic membrane (SFDM) separation was applied to the conventional sludge fermenter for improving VFA yields. Results indicated SFDM presented good performance in transferring products, retaining substrates, and enriching useful bacteria. The retention ratios of suspended solids, soluble COD, proteins, and polysaccharides reached 99%, 30%, 70%, and 40%, respectively, and more than 90% of the VFAs and ammonia could be transferred in a timely manner. The structure of the microbial community was optimized, which led to enhanced releases of hydrolytic enzymes and accelerated enrichments of functional bacteria. Protease and β-glucosidase activities increased from 1.0 to 5.0U/mL and 15.0 to 23.0μmol/L·h, respectively. VFA yield and sludge conversion ratio increased by 233.3% and 227.9%, respectively. Moreover, SFDM had good operation stability, including a short formation time, a long operation period, and a low transmembrane pressure. These results show VFA yield from sludge fermentation can be greatly improved by SFDM separation. PMID:27347803

  1. Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of K East Area Sludge Composite

    Laboratory tests were performed to examine the efficacy of various leach treatments for decontaminating dissolver residual solids (KEACRESID1) produced during a 24-hour dissolution of K East Basin floor and Weasel Pit sludge composite in boiling 6 M HNO3. The scope of this testing has been described in Section 4.5 of ''Testing Strategy to Support the Development of K Basin Sludge Treatment Process'' (Flament 1998). Radionuclides sorbed or associated with the residual solids generated in the K Basin sludge treatment process can restrict disposal of this solid to the Environmental Restoration Disposal Facility (ERDF). The starting dissolver residual solid for this testing, KEACRESID1, is a visibly heterogeneous material. This material contains radionuclides at concentrations above the ERDF Waste Acceptance Criteria for transuranics (TRU) by about a factor of 3, for 239Pu by a factor of 10, and for 241Am by a factor of 1.6. It meets the ERDF criterion for 137Cs by a factor of 4 and for uranium by a factor of 10. Therefore, the radionuclides of greatest interest in this leaching study are first 239Pu, and then 241Am, 137Cs, and uranium

  2. GLYCOLIC-NITRIC ACID FLOWSHEET DEMONSTRATION OF THE DWPF CHEMICAL PROCESS CELL WITH SLUDGE AND SUPERNATE SIMULANTS

    Lambert, D.; Stone, M.; Newell, J.; Best, D.; Zamecnik, J.

    2012-08-28

    Savannah River Remediation (SRR) is evaluating changes to its current Defense Waste Processing Facility (DWPF) flowsheet to improve processing cycle times. This will enable the facility to support higher canister production while maximizing waste loading. Higher throughput is needed in the Chemical Process Cell (CPC) since the installation of the bubblers into the melter has increased melt rate. Due to the significant maintenance required for the DWPF gas chromatographs (GC) and the potential for production of flammable quantities of hydrogen, reducing or eliminating the amount of formic acid used in the CPC is being developed. Earlier work at Savannah River National Laboratory has shown that replacing formic acid with an 80:20 molar blend of glycolic and formic acids has the potential to remove mercury in the SRAT without any significant catalytic hydrogen generation. This report summarizes the research completed to determine the feasibility of processing without formic acid. In earlier development of the glycolic-formic acid flowsheet, one run (GF8) was completed without formic acid. It is of particular interest that mercury was successfully removed in GF8, no formic acid at 125% stoichiometry. Glycolic acid did not show the ability to reduce mercury to elemental mercury in initial screening studies, which is why previous testing focused on using the formic/glycolic blend. The objective of the testing detailed in this document is to determine the viability of the nitric-glycolic acid flowsheet in processing sludge over a wide compositional range as requested by DWPF. This work was performed under the guidance of Task Technical and Quality Assurance Plan (TT&QAP). The details regarding the simulant preparation and analysis have been documented previously.

  3. Coal tar phototherapy for psoriasis reevaluated: erythemogenic versus suberythemogenic ultraviolet with a tar extract in oil and crude coal tar

    Recent studies have questioned the therapeutic value of coal tar versus ultraviolet (UV) radiation and their relative necessity in phototherapy for psoriasis. In this investigation, different aspects of tar phototherapy have been studied in single-blind bilateral paired comparison studies. The effects of 1% crude coal tar were compared with those of petrolatum in conjunction with erythemogenic and suberythemogenic doses of ultraviolet light (UVB) using a FS72 sunlamp tubed cabinet. Crude coal tar was clinically superior to petrolatum with suberythemogenic ultraviolet. With the erythemogenic UVB, petrolatum was equal in efficacy to crude coal tar. Suberythemogenic UVB was also used adjunctively to compare the effects of a 5% concentration of a tar extract in an oil base to 5% crude coal tar in petrolatum or the oil base without tar. The tar extract in oil plus suberythemogenic UVB produced significantly more rapid improvement than the oil base plus UVB. The direct bilateral comparison of equal concentrations of tar extract in oil base versus crude coal tar in petrolatum in a suberythemogenic UV photo regimen revealed no statistical differences between treatments. In a study comparing tar extract in oil and the oil base without ultraviolet radiation, the tar extract in oil side responded more rapidly

  4. An efficient and green pretreatment to stimulate short-chain fatty acids production from waste activated sludge anaerobic fermentation using free nitrous acid.

    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

  5. Hygienisation and nutrient conservation of sewage sludge or cattle manure by lactic acid fermentation.

    Hendrik A Scheinemann

    Full Text Available Manure from animal farms and sewage sludge contain pathogens and opportunistic organisms in various concentrations depending on the health of the herds and human sources. Other than for the presence of pathogens, these waste substances are excellent nutrient sources and constitute a preferred organic fertilizer. However, because of the pathogens, the risks of infection of animals or humans increase with the indiscriminate use of manure, especially liquid manure or sludge, for agriculture. This potential problem can increase with the global connectedness of animal herds fed imported feed grown on fields fertilized with local manures. This paper describes a simple, easy-to-use, low-tech hygienization method which conserves nutrients and does not require large investments in infrastructure. The proposed method uses the microbiotic shift during mesophilic fermentation of cow manure or sewage sludge during which gram-negative bacteria, enterococci and yeasts were inactivated below the detection limit of 3 log10 cfu/g while lactobacilli increased up to a thousand fold. Pathogens like Salmonella, Listeria monocytogenes, Staphylococcus aureus, E. coli EHEC O:157 and vegetative Clostridium perfringens were inactivated within 3 days of fermentation. In addition, ECBO-viruses and eggs of Ascaris suum were inactivated within 7 and 56 days, respectively. Compared to the mass lost through composting (15-57%, the loss of mass during fermentation (< 2.45% is very low and provides strong economic and ecological benefits for this process. This method might be an acceptable hygienization method for developed as well as undeveloped countries, and could play a key role in public and animal health while safely closing the nutrient cycle by reducing the necessity of using energy-inefficient inorganic fertilizer for crop production.

  6. Hygienisation and nutrient conservation of sewage sludge or cattle manure by lactic acid fermentation.

    Scheinemann, Hendrik A; Dittmar, Katja; Stöckel, Frank S; Müller, Hermann; Krüger, Monika E

    2015-01-01

    Manure from animal farms and sewage sludge contain pathogens and opportunistic organisms in various concentrations depending on the health of the herds and human sources. Other than for the presence of pathogens, these waste substances are excellent nutrient sources and constitute a preferred organic fertilizer. However, because of the pathogens, the risks of infection of animals or humans increase with the indiscriminate use of manure, especially liquid manure or sludge, for agriculture. This potential problem can increase with the global connectedness of animal herds fed imported feed grown on fields fertilized with local manures. This paper describes a simple, easy-to-use, low-tech hygienization method which conserves nutrients and does not require large investments in infrastructure. The proposed method uses the microbiotic shift during mesophilic fermentation of cow manure or sewage sludge during which gram-negative bacteria, enterococci and yeasts were inactivated below the detection limit of 3 log10 cfu/g while lactobacilli increased up to a thousand fold. Pathogens like Salmonella, Listeria monocytogenes, Staphylococcus aureus, E. coli EHEC O:157 and vegetative Clostridium perfringens were inactivated within 3 days of fermentation. In addition, ECBO-viruses and eggs of Ascaris suum were inactivated within 7 and 56 days, respectively. Compared to the mass lost through composting (15-57%), the loss of mass during fermentation (< 2.45%) is very low and provides strong economic and ecological benefits for this process. This method might be an acceptable hygienization method for developed as well as undeveloped countries, and could play a key role in public and animal health while safely closing the nutrient cycle by reducing the necessity of using energy-inefficient inorganic fertilizer for crop production. PMID:25786255

  7. Nutrient leaching potential following application of papermill lime-sludge to an acidic clay soil

    S. C. Vettorazzo; F. C. S. Amaral; J. C. Chitolina

    2001-01-01

    This experiment was carried out under greenhouse conditions with soil pots during 210 days, to evaluate the effect of calcitic papermill lime-sludge application (at the rates 0, 773, 1.547, and 2.320 mg kg-1 or respective equivalents to control, 2, 4, and 6 t ha-1), on chemical composition of soil leachate and its effects on eucalypt growth and yield. Highest soil leachate pH, SO4, and Na concentrations occurred in the 4 and 6 t ha-1 treatments. Soil leachate nitrate concentrations decreased ...

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

    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)

  9. A new insight into resource recovery of excess sewage sludge: Feasibility of extracting mixed amino acids as an environment-friendly corrosion inhibitor for industrial pickling

    Su, Wen; Tang, Bing, E-mail: renytang@163.com; Fu, Fenglian; Huang, Shaosong; Zhao, Shiyuan; Bin, Liying; Ding, Jiewei; Chen, Cuiqun

    2014-08-30

    Graphical abstract: - Highlights: • A value-added product was extracted from the municipal excess sludge. • The effective components contained in the product were mixed amino acids. • The product could provide a reliable protection to the steel from the acid medium. • A new insight into the resource recovery of excess sewage sludge was provided. - Abstract: The work mainly presented a laboratory-scale investigation on an effective process to extract a value-added product from municipal excess sludge. The functional groups in the hydrolysate were characterized with Fourier transform infrared spectrum, and the contained amino acids were measured by means of an automatic amino acid analyzer. The corrosion-inhibition characteristics of the hydrolysate were determined with weight-loss measurement, electrochemical polarization and scanning electron microscopy. Results indicated that the hydrolysate contained 15 kinds of amino acid, and their adsorption on the surface could effectively inhibit the corrosion reaction of the steel from the acid medium. Polarization curves indicated that the obtained hydrolysate was a mixed-type inhibitor, but mainly restricted metal dissolution on the anode. The adsorption accorded well with the Langmuir adsorption isotherm, involved an increase in entropy, and was a spontaneous, exothermic process.

  10. A new insight into resource recovery of excess sewage sludge: Feasibility of extracting mixed amino acids as an environment-friendly corrosion inhibitor for industrial pickling

    Graphical abstract: - Highlights: • A value-added product was extracted from the municipal excess sludge. • The effective components contained in the product were mixed amino acids. • The product could provide a reliable protection to the steel from the acid medium. • A new insight into the resource recovery of excess sewage sludge was provided. - Abstract: The work mainly presented a laboratory-scale investigation on an effective process to extract a value-added product from municipal excess sludge. The functional groups in the hydrolysate were characterized with Fourier transform infrared spectrum, and the contained amino acids were measured by means of an automatic amino acid analyzer. The corrosion-inhibition characteristics of the hydrolysate were determined with weight-loss measurement, electrochemical polarization and scanning electron microscopy. Results indicated that the hydrolysate contained 15 kinds of amino acid, and their adsorption on the surface could effectively inhibit the corrosion reaction of the steel from the acid medium. Polarization curves indicated that the obtained hydrolysate was a mixed-type inhibitor, but mainly restricted metal dissolution on the anode. The adsorption accorded well with the Langmuir adsorption isotherm, involved an increase in entropy, and was a spontaneous, exothermic process

  11. Adsorption of acid red from dye wastewater by Zn{sub 2}Al-NO{sub 3} LDHs and the resource of adsorbent sludge as nanofiller for polypropylene

    Xue, Tianshan; Gao, Yanshan; Zhang, Zhang [College of Environmental Science and Engineering, Beijing Forestry University, 35 Qinghua East Road, Haidian District, Beijing 100083 (China); Umar, Ahmad, E-mail: ahmadumar786@gmail.com [Department of Chemistry, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Yan, Xingru; Zhang, Xi; Guo, Zhanhu [Integrated Composites Laboratory, Dan F Smith Department of Chemical Engineering, Lamar University, Beaumont, TX 77710 (United States); Wang, Qiang, E-mail: qiang.wang.ox@gmail.com [College of Environmental Science and Engineering, Beijing Forestry University, 35 Qinghua East Road, Haidian District, Beijing 100083 (China)

    2014-02-25

    Highlights: • High removal efficiency of acid red 97 from dye wastewater was achieved by using Zn{sub 2}Al-NO{sub 3} LDHs adsorbent. • The resource of the LDH adsorbent sludge as nanofiller for polypropylene (PP) was proposed for the first time. • The thermal stability of PP was significantly improved by introducing only small amount of LDH adsorbent sludge. • The resource the dye adsorbent sludge as multifunctional nanofiller for polymers is a very promising option. -- Abstract: In this contribution, we report the removal of acid red 97 (AC97) from simulated dye wastewater by using Zn{sub 2}Al-NO{sub 3} layered double hydroxides (LDHs) adsorbent, and the resource of the LDH adsorbent sludge as nanofiller for polypropylene (PP) for the first time. The obtained Zn{sub 2}Al-NO{sub 3} LDH was analyzed using X-ray diffraction and scanning electron microscopy analysis, confirming the formation of pure and platelike LDH nanoparticles. The effects of adsorption time and initial dye concentration on the removal of AC97 from wastewater were systematically investigated, showing that the Zn{sub 2}Al-NO{sub 3} LDHs is very efficient in removing AC97. The saturated adsorption capacity of water washed and acetone washed Zn{sub 2}Al-LDHs is 204.4 and 299.5 mg/g, respectively. Finally, the LDH adsorbent sludge was added into PP using a modified solvent mixing method. Thermal gravimetric analysis and ultraviolet (UV) absorption analysis of PP/Zn{sub 2}Al-AC97 LDHs nanocomposites suggested that the Zn{sub 2}Al-AC97 LDH can significantly improve the thermal stability and UV shielding ability of PP. This data demonstrated that it is very promising to resource the dye adsorbent sludge as multifunctional nanofiller for polymers.

  12. Adsorption of acid red from dye wastewater by Zn2Al-NO3 LDHs and the resource of adsorbent sludge as nanofiller for polypropylene

    Highlights: • High removal efficiency of acid red 97 from dye wastewater was achieved by using Zn2Al-NO3 LDHs adsorbent. • The resource of the LDH adsorbent sludge as nanofiller for polypropylene (PP) was proposed for the first time. • The thermal stability of PP was significantly improved by introducing only small amount of LDH adsorbent sludge. • The resource the dye adsorbent sludge as multifunctional nanofiller for polymers is a very promising option. -- Abstract: In this contribution, we report the removal of acid red 97 (AC97) from simulated dye wastewater by using Zn2Al-NO3 layered double hydroxides (LDHs) adsorbent, and the resource of the LDH adsorbent sludge as nanofiller for polypropylene (PP) for the first time. The obtained Zn2Al-NO3 LDH was analyzed using X-ray diffraction and scanning electron microscopy analysis, confirming the formation of pure and platelike LDH nanoparticles. The effects of adsorption time and initial dye concentration on the removal of AC97 from wastewater were systematically investigated, showing that the Zn2Al-NO3 LDHs is very efficient in removing AC97. The saturated adsorption capacity of water washed and acetone washed Zn2Al-LDHs is 204.4 and 299.5 mg/g, respectively. Finally, the LDH adsorbent sludge was added into PP using a modified solvent mixing method. Thermal gravimetric analysis and ultraviolet (UV) absorption analysis of PP/Zn2Al-AC97 LDHs nanocomposites suggested that the Zn2Al-AC97 LDH can significantly improve the thermal stability and UV shielding ability of PP. This data demonstrated that it is very promising to resource the dye adsorbent sludge as multifunctional nanofiller for polymers

  13. Treating tar sands formations with karsted zones

    Vinegar, Harold J. (Bellaire, TX); Karanikas, John Michael (Houston, TX)

    2010-03-09

    Methods for treating a tar sands formation are described herein. The tar sands formation may have one or more karsted zones. Methods may include providing heat from one or more heaters to one or more karsted zones of the tar sands formation to mobilize fluids in the formation. At least some of the mobilized fluids may be produced from the formation.

  14. Reclamation of acid, toxic coal spoils using wet flue gas desulfurization by-product, fly ash and sewage sludge. Final report

    Kost, D.A.; Vimmerstedt, J.P.; Stehouwer, R.C.

    1997-03-01

    Establishment of vegetation on acid abandoned minelands requires modification of soil physical and chemical conditions. Covering the acid minesoil with topsoil or borrow soil is a common practice but this method may be restricted by availability of borrow soil and cause damage to the borrow site. An alternative approach is to use waste materials as soil amendments. There is a long history of using sewage sludge and fly ash as amendments for acid minesoils. Flue gas desulfurization (FGD) by-products are newer materials that are also promising amendments. Most flue gas sludges are mixtures of Calcium sulfate (CaSO{sub 4}), calcium sulfite (CaSO{sub 3}), calcium carbonate (CaCO{sub 3}), calcium hydroxide [Ca(OH){sub 2}], and fly ash. Some scrubbing processes produce almost pure gypsum (CaSO{sub 4}2H{sub 2}O). The primary purpose of the project is to evaluate two wet FGD by-products for effects on vegetation establishment and surface and ground water quality on an acid minesoil. One by-product from the Conesville, OH power plant (American Electric Power Service Corporation) contains primarily calcium sulfite and fly ash. The other by-product (Mg-gypsum FGD) from an experimental scrubber at the Zimmer power plant (Cincinnati Gas and Electric Company) is primarily gypsum with 4% magnesium hydroxide. These materials were compared with borrow soil and sewage sludge as minesoil amendments. Combinations of each FGD sludge with sewage sludge were also tested. This report summarizes two years of measurements of chemical composition of runoff water, ground water at two depths in the subsoil, soil chemical properties, elemental composition and yield of herbaceous ground cover, and elemental composition, survival and height of trees planted on plots treated with the various amendments. The borrow soil is the control for comparison with the other treatments.

  15. Reclamation of acid, toxic coal spoils using wet flue gas desulfurization by-product, fly ash and sewage sludge. Final report

    Establishment of vegetation on acid abandoned minelands requires modification of soil physical and chemical conditions. Covering the acid minesoil with topsoil or borrow soil is a common practice but this method may be restricted by availability of borrow soil and cause damage to the borrow site. An alternative approach is to use waste materials as soil amendments. There is a long history of using sewage sludge and fly ash as amendments for acid minesoils. Flue gas desulfurization (FGD) by-products are newer materials that are also promising amendments. Most flue gas sludges are mixtures of Calcium sulfate (CaSO4), calcium sulfite (CaSO3), calcium carbonate (CaCO3), calcium hydroxide [Ca(OH)2], and fly ash. Some scrubbing processes produce almost pure gypsum (CaSO42H2O). The primary purpose of the project is to evaluate two wet FGD by-products for effects on vegetation establishment and surface and ground water quality on an acid minesoil. One by-product from the Conesville, OH power plant (American Electric Power Service Corporation) contains primarily calcium sulfite and fly ash. The other by-product (Mg-gypsum FGD) from an experimental scrubber at the Zimmer power plant (Cincinnati Gas and Electric Company) is primarily gypsum with 4% magnesium hydroxide. These materials were compared with borrow soil and sewage sludge as minesoil amendments. Combinations of each FGD sludge with sewage sludge were also tested. This report summarizes two years of measurements of chemical composition of runoff water, ground water at two depths in the subsoil, soil chemical properties, elemental composition and yield of herbaceous ground cover, and elemental composition, survival and height of trees planted on plots treated with the various amendments. The borrow soil is the control for comparison with the other treatments

  16. Effect of organic load on decolourization of textile wastewater containing acid dyes in upflow anaerobic sludge blanket reactor

    Textile wastewater (TW) is one of the most hazardous wastewater for the environment when discharged without proper treatment. Biological treatment technologies have shown encouraging results over the treatment of recalcitrant compounds containing wastewaters. Upflow anaerobic sludge blanket reactor (UASB) was evaluated in terms of colour and the reduction of chemical oxygen demand (COD) with different organic loads using TW containing dyes belonging to different chemical groups. The study was performed using six different dye concentrations (10 mg/L, 25 mg/L, 50 mg/L, 100 mg/L, 150 mg/L, 300 mg/L) with three COD levels (∼1000 mg/L, ∼2000 mg/L, ∼3000 mg/L). Decolourization, COD removal and reactor stability were monitored. Over 85% of colour removal was observed with all dye concentrations with three organic loads. Acid Red 131 and Acid Yellow 79 were decolourized through biodegradation while Acid Blue 204 was decolourized due to adsorption onto anaerobic granules. COD removal was high in all dye concentrations, regardless of co-substrate levels. The reactor did not show any instability during the study. The activity of granules was not affected by the dyes. Methanothrix like bacteria were the dominant group in granules before introducing TW, however, they were reduced and cocci-shape microorganism increased after the treatment of textile wastewater.

  17. Biodiesel production from the lipid of wastewater sludge using an acidic heterogeneous catalyst

    Siddiquee, M.N.; Kazemian, H.; Rohani, S. [University of Western Ontario, Department of Chemical and Biochemical Engineering, London, ON (Canada)

    2011-12-15

    The production of biodiesel from the lipid of wastewater sludge was studied using SBA-15 impregnated with the heteropolyacid H{sub 3}PO{sub 4}.12WO{sub 3}.xH{sub 2}O (PW{sub 12}) as a mesoporous heterogeneous catalyst. X-ray diffraction, Brunauer-Emmett-Teller surface area, thermalgravimetric analysis, and scanning electron microscopy were applied to characterize the prepared catalysts. Catalytic performances were evaluated in a microreactor setup under different experimental conditions. The biodiesel yield for a sample impregnated with 15 % PW{sub 12} was 30.14 wt-% at a temperature of 135 C and a pressure of 135 psi for 3 h reaction time. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Removal of Anabaena flos-aquae in water treatment process using Moringa oleifera and assessment of fatty acid profile of generated sludge.

    Moreti, Livia O R; Coldebella, Priscila Ferri; Camacho, Franciele P; Carvalho Bongiovani, Milene; Pereira de Souza, Aloisio Henrique; Kirie Gohara, Aline; Matsushita, Makoto; Fernandes Silva, Marcela; Nishi, Letícia; Bergamasco, Rosângela

    2016-01-01

    This study aimed to evaluate the efficiency of the coagulation/flocculation/dissolved air flotation (C/F/DAF) process using the coagulant Moringa oleifera (MO) seed powder, and to analyse the profile of fatty acids present in the generated sludge after treatment. For the tests, deionized water artificially contaminated with cell cultures of Anabaena flos-aquae was used, with a cell density in the order of 10(4) cells mL(-1). C/F/DAF tests were conducted using 'Flotest' equipment. For fatty acid profile analyses, a gas chromatograph equipped with a flame ionization detector was used. It was seen that the optimal dosage (100 mg L(-1)) of MO used in the C/F/DAF process was efficient at removing nearly all A. flos-aquae cells (96.4%). The sludge obtained after treatment contained oleic acid (61.7%) and palmitic acid (10.8%). Thus, a water treatment process using C/F/DAF linked to integral MO powder seed was found to be efficient in removing cells of cyanobacteria, and produced a sludge rich in oleic acid that is a precursor favourable for obtaining quality biodiesel, thus becoming an alternative application for the recycling of such biomass. PMID:26586082

  19. Achieving Stable Nitritation for Mainstream Deammonification by Combining Free Nitrous Acid-Based Sludge Treatment and Oxygen Limitation

    Wang, Dongbo; Wang, Qilin; Laloo, Andrew; Xu, Yifeng; Bond, Philip L.; Yuan, Zhiguo

    2016-05-01

    Stable nitritation is a critical bottleneck for achieving autotrophic nitrogen removal using the energy-saving mainstream deammonification process. Herein we report a new strategy to wash out both the Nitrospira sp. and Nitrobacter sp. from the treatment of domestic-strength wastewater. The strategy combines sludge treatment using free nitrous acid (FNA) with dissolved oxygen (DO) control in the nitritation reactor. Initially, the nitrifying reactor achieved full conversion of NH4+ to NO3‑. Then, nitrite accumulation at ~60% was achieved in the reactor when 1/4 of the sludge was treated daily with FNA at 1.82 mg N/L in a side-stream unit for 24 h. Fluorescence in-situ hybridization (FISH) revealed FNA treatment substantially reduced the abundance of nitrite oxidizing bacteria (NOB) (from 23.0 ± 4.3 to 5.3 ± 1.9%), especially that of Nitrospira sp. (from 15.7 ± 3.9 to 0.4 ± 0.1%). Nitrite accumulation increased to ~80% when the DO concentration in the mainstream reactor was reduced from 2.5–3.0 to 0.3–0.8 mg/L. FISH revealed the DO limitation further reduced the abundance of NOB (to 2.1 ± 1.0%), especially that of Nitrobacter sp. (from 4.9 ± 1.2 to 1.8 ± 0.8%). The strategy developed removes a major barrier for deammonification in low-strength domestic wastewater.

  20. Quantitative analysis of phenol and alkylphenols in Brazilian coal tar

    Elina Bastos Caramão; Irajá do Nascimento Filho

    2004-01-01

    The main purpose of this work is the identification and quantification of phenolic compounds in coal tar samples from a ceramics factory in Cocal (SC), Brazil. The samples were subjected to preparative scale liquid chromatography, using Amberlyst A-27TM ion-exchange resin as stationary phase. The fractions obtained were classified as "acids" and "BN" (bases and neutrals). The identification and quantification of phenols, in the acid fraction, was made by gas chromatography coupled to mass spe...

  1. Improved volatile fatty acids anaerobic production from waste activated sludge by pH regulation: Alkaline or neutral pH?

    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

  2. Relationship Between the Composition and Interfacial Tension of Former Manufactured Gas Plant Tars

    Hauswirth, S.; Birak, P. S.; Miller, C. T.

    2011-12-01

    Former manufactured gas plant (FMGP) tars pose significant environmental hazards and present a challenge to regulators and industry professionals. The tars, which were produced as a byproduct of the gas manufacturing process, were frequently released into the environment through improper disposal or leaks in plant infrastructure. The interfacial tension (IFT) is a primary factor controlling the mobility of tars in porous media, and is therefore important to understand for both predicting the migration of tars and designing remediation strategies. In this study, we characterized nine field-collected FMGP tars and a commercially available coal tar by means of chemical extractions (asphaltenes, resins, acids, and bases), gas chromatography-mass spectrometry (GC-MS), and Fourier transform infrared (FTIR) spectroscopy. Additionally, the IFT and contact angle of each tar was determined for a pH range of 3-11. The IFT was found to be similar for all tars at pH 5 and 7 regardless of composition. Slight decreases in IFT at lower pH were correlated with higher concentrations of extractable bases, which consisted primarily of nitrogen-containing heterocyclic aromatic compounds. Much greater reductions of IFT were observed at high pH. These reductions were found to be associated with the presence of carbonyl or carboxyl groups in the asphaltenes. It is likely that the larger size of the asphaltene molecules (as compared to the extractable compounds) resulted in species with greater surface activity when ionized.

  3. Biological hydrolysis and acidification of sludge under anaerobic conditions: The effect of sludge type and origin on the production and composition of olatile fatty acids

    Ucisik, Ahmed Süheyl; Henze, Mogens

    2008-01-01

    .1–12.6% COD-yields, soluble COD (SCOD)/total COD (TCOD), in batch experiments, respectively. The COD-yields for primary, activated and mixed sludge were 19.1%, 6.5% and 21.37%, respectively, in semi-continuous experiments operated at solids retention time (SRT) of 5 d and temperature of 37 °C. The benefit of...

  4. Fermentative Conversion of Cellulose to Acetic Acid and Cellulolytic Enzyme Production by a Bacterial Mixed Culture Obtained from Sewage Sludge

    Khan, A. W.; Wall, Duncan; L. Van Den Berg

    1981-01-01

    A simple procedure that uses a cellulose-enriched culture started from sewage sludge was developed for producing cellulolytic enzymes and converting cellulose to acetic acid rather than CH4 and CO2. In this procedure, the culture which converts cellulose to CH4 and CO2 was mixed with a synthetic medium and cellulose and heated to 80°C for 15 min before incubation. The end products formed were acetic acid, propionic acid, CO2, and traces of ethanol and H2. Supernatants from 6- to 10-day-old cu...

  5. Combined Determination of Poly-β-Hydroxyalkanoic and Cellular Fatty Acids in Starved Marine Bacteria and Sewage Sludge by Gas Chromatography with Flame Ionization or Mass Spectrometry Detection

    Odham, Göran; Tunlid, Anders; Westerdahl, Gunilla; Mårdén, Per

    1986-01-01

    Extraction of lipids from bacterial cells or sewage sludge samples followed by simple and rapid extraction procedures and room temperature esterification with pentafluorobenzylbromide allowed combined determinations of poly-β-hydroxyalkanoate constituents and fatty acids. Capillary gas chromatography and flame ionization or mass spectrometric detection was used. Flame ionization permitted determination with a coefficient of variation ranging from 10 to 27% at the picomolar level, whereas quan...

  6. Application of waterworks sludge in wastewater treatment plants

    Sharma, Anitha Kumari; Thornberg, D.; Andersen, Henrik Rasmus

    2013-01-01

    The potential for reuse of iron-rich sludge from waterworks as a replacement for commercial iron salts in wastewater treatment was investigated using acidic and anaerobic dissolution. The acidic dissolution of waterworks sludge both in sulphuric acid and acidic products such as flue gas washing......, and are economically and environmentally more favourable compared to deposition of the waterworks sludge in controlled landfills....

  7. The extraction of bitumen from western tar sands. Annual report, July 1990--July 1991

    Oblad, A.G.; Bunger, J.W.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1992-04-01

    Contents of this report include the following: executive summary; characterization of the native bitumen from the Whiterocks oil sand deposit; influence of carboxylic acid content on bitumen viscosity; water based oil sand separation technology; extraction of bitumen from western oil sands by an energy-efficient thermal method; large- diameter fluidized bed reactor studies; rotary kiln pyrolysis of oil sand; catalytic upgrading of bitumen and bitumen derived liquids; ebullieted bed hydrotreating and hydrocracking; super critical fluid extraction; bitumen upgrading; 232 references; Appendix A--Whiterocks tar sand deposit bibliography; Appendix B--Asphalt Ridge tar sand deposit bibliography; and Appendix C--University of Utah tar sands bibliography.

  8. Structural study of humic acids during composting of activated sludge-green waste: Elemental analysis, FTIR and 13C NMR

    The humic acids extracted from a compost of activated sludge at different stages of maturity were characterized by various chemical techniques. Elemental analysis showed the reduction of H, and the H/C and C/N ratios and an increase in the proportion of N and S. At the end of composting C% and O% presented the same values as initially, although they increased in the intermediate stage. Based on the ratios of FTIR absorbance it was shown that the end product was enriched in etherified and peptidic compounds absorbing at 1384, 1034 and 1544 cm-1. The alkyl and other N-rich and oxidized recalcitrant structures compose the new humic polymers produced during composting. In principal components analysis, the first axis, PC1: 49.75% considers the variability between structures in decomposition from the other parameters that concern the stable new humic polymers formed after composting. PC2 (40.5%) shows a negative correlation between (aromatic carbon, FA level) and (aliphatic carbon, HA level) during composting.

  9. Kinetic analysis of waste activated sludge hydrolysis and short-chain fatty acids production at pH 10

    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.

  10. Reuse of sewage sludge as a catalyst in ozonation - Efficiency for the removal of oxalic acid and the control of bromate formation

    Wen, Gang [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Pan, Zhi-Hui [School Of Civil Engineering, Guangzhou University, Guangzhou 510006 (China); Ma, Jun, E-mail: majun@hit.edu.cn [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Liu, Zheng-Qian, E-mail: liuzhengqian@gmail.com [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhao, Lei [School of Civil Engineering, Harbin Institute of Technology, Harbin 150090 (China); Li, Jun-Jing [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Sewage sludge was converted into catalyst (SBC) and characterized. Black-Right-Pointing-Pointer SBC can enhance oxalic acid degradation in ozonation. Black-Right-Pointing-Pointer Surface reaction mechanism is responsible for enhancement of ozonation by SBC. Black-Right-Pointing-Pointer SBC can control the formation of bromate in ozonation. Black-Right-Pointing-Pointer Several combined reasons for the control of bromate formation are proposed. - Abstract: Sewage derived sludge is produced with an annual amount increase of 2% all over the world and it is an urgent issue to be addressed by human being. In the present study, sludge was converted into sludge-based catalyst (SBC) with ZnCl{sub 2} as activation agent and characterized by several methods (e.g., scanning electron microscope, X-ray photoelectron spectroscope and Fourier transform infrared spectroscope). Then it was used as a catalyst to enhance the removal of refractory organic matter, oxalic acid, and to control the formation of bromate (BrO{sub 3}{sup -}) in bench semi-continuous ozonation experiments. The effects of various operating parameters on the control of BrO{sub 3}{sup -} formation were investigated. Furthermore, the mechanism for the enhancement of organic matter removal and the control of BrO{sub 3}{sup -} formation was discussed as well. Results indicate that the combination of SBC with ozone shows a strong synergistic effect, resulting in a notable improvement on oxalic acid removal. A crucial surface reaction mechanism for the enhancement of organic matter removal is proposed on the basis of negative effect of higher pH and no inhibition effect of tert-butanol. The control for BrO{sub 3}{sup -} formation was demonstrated and the reason for its control in the process of O{sub 3}/SBC is the combined effect of SBC reductive properties, ozone exposure decrease and hydrogen peroxide concentration increase.

  11. Quantitative analysis of phenol and alkylphenols in Brazilian coal tar

    Elina Bastos Caramão

    2004-04-01

    Full Text Available The main purpose of this work is the identification and quantification of phenolic compounds in coal tar samples from a ceramics factory in Cocal (SC, Brazil. The samples were subjected to preparative scale liquid chromatography, using Amberlyst A-27TM ion-exchange resin as stationary phase. The fractions obtained were classified as "acids" and "BN" (bases and neutrals. The identification and quantification of phenols, in the acid fraction, was made by gas chromatography coupled to mass spectrometry (GC/MS. Nearly twenty-five phenols were identified in the samples and nine of them were also quantified. The results showed that coal tar has large quantities of phenolic compounds of industrial interest.

  12. Tar ball Monitoring Along the Kenyan Beaches.

    Nguta, M.

    1993-01-01

    Observations and measurements of petroleum tar balls on a number of Kenyan beaches were carried out between 1979 and 1982. A large variation in the size and amount of tar deposit at the beaches was recorded. These values ranged from very small pebbles to large lumps of 30 cm in diameter, weighing up to 1.5 kg. The average tar loading during the sampling period ranged from 0-18 g/m2. Between 25-50% by weight of the tar lumps were shell fragments, sand and other nonpetroleum debris. The chemica...

  13. Production of high optical purity l-lactic acid from waste activated sludge by supplementing carbohydrate: effect of temperature and pretreatment time.

    Jian, Qiwei; Li, Xiang; Chen, Yinguang; Liu, Yanan; Pan, Yin

    2016-10-01

    It has been widely accepted that the most environmentally beneficial way to treat waste activated sludge (WAS), the byproduct of municipal wastewater treatment plant, is to recover the valuable organic acid. However, the bio-conversion of lactic acid, one of the high added-value chemical, is seldom reported from WAS fermentation. In this paper, l-lactic acid was observed dominant in the WAS fermentation liquid with carbohydrate addition at ambient temperature. Furthermore, the effect of temperature on l-lactic acid and d-lactic acid production was fully discussed: two isomers were rapidly produced and consumed up in one day at mesophilic condition; and almost optically pure l-lactic acid was generated at thermophilic condition, yet time-consuming with yield of l-lactic acid enhancing by 52.9% compared to that at ambient temperature. The study mechanism showed that mesophilic condition was optimal for both production and consumption of l-lactic acid and d-lactic acid, while consumption of l-lactic acid and production of d-lactic acid were severely inhibited at thermophilic condition. Therefore, by maintaining thermophilic for 4 h in advance and subsequently fermenting mesophilic for 34 h, the concentration of l-lactic acid with optical activity of 98.3% was improved to 16.6 ± 0.5 g COD/L at a high specific efficiency of 0.6097/d. PMID:26878176

  14. Feeding behavior and trophic relationship of earthworms and other predators in vermifiltration system for liquid-state sludge stabilization using fatty acid profiles.

    Xing, Meiyan; Zhao, Chunhui; Yang, Jian; Lv, Baoyi

    2014-10-01

    The sludge reduction capability (VSS reduction) of vermifilter (VF) was 14.7% higher than that of conventional biofilter (BF) due to the fact that there was a net loss of biomass and energy when the food web in VF is extended. Therefore, feeding behavior and trophic relationship of earthworms and other predators (leeches, lymnaeidaes and limaxes) in VF were investigated using fatty acid (FA) profiles for the first time. Compared with BF biofilm, microbial community structure of VF biofilm got optimized by earthworms that the percentage of protozoa increased from 14.2% to 20.4%. Furthermore, analysis of specific microbial FAs composition in each predator suggested different trophic level of predators resulted from their selective ingestion of different microorganisms, and earthworms were at the second high trophic level in VF food web. Overall findings indicated earthworms modified microbial community and extended the food web of VF and thus enhanced the sludge reduction. PMID:25043348

  15. Continuous hydrogen production from mixed organic acids by an enriched phototrophic sludge

    Li, R.; Zhang, T.; Fang, HHP

    2007-01-01

    BACKGROUND: Phototrophic fermentation is one of the most promising processes to produce hydrogen, with higher substrates utilization efficiency compared to the dark fermentation, since it can utilize the byproduct of dark fermentation, the organic acids. The combination of dark and photo fermentation has been proposed as an efficient process. In order to put the two-step hydrogen producing process into practical application, a continuous phototrophic hydrogen production system should be condu...

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

    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...

  17. Sludge treatment studies

    Solid formation in filtered leachates and wash solutions was seen in five of the six sludges treated by Enhanced Sludge Washing. Solid formation in process solutions takes a variety of forms: very fine particles, larger particulate solids, solids floating in solution like egg whites, gels, crystals, and coatings on sample containers. A gel-like material that formed in a filtered leachate from Enhanced Sludge Washing of Hanford T-104 sludge was identified as natrophosphate, Na7(PO4)2F·19H2O. A particulate material that formed in a filtered caustic leachate from Hanford SX-113 sludge contained sodium and silicon. This could be any of a host of sodium silicates in the NaOH-SiO2-H2O system. Acidic treatment of Hanford B-202 sludge with 1 M, 3 M, and 6 M HNO3 sequential leaching resulted in complete dissolution at 75 C, but not at ambient temperature. This treatment resulted in the formation of solids in filtered leachates. Analyses of the solids revealed that a gel material contained silica with some potassium, calcium, iron, and manganese. Two phases were embedded in the gel. One was barium sulfate. The other could not be identified, but it was determined that the only metal it contained was bismuth

  18. Sludge treatment studies

    Beahm, E.C.; Weber, C.F.; Dillow, T.A.; Bush, S.A.; Lee, S.Y.; Hunt, R.D.

    1997-06-01

    Solid formation in filtered leachates and wash solutions was seen in five of the six sludges treated by Enhanced Sludge Washing. Solid formation in process solutions takes a variety of forms: very fine particles, larger particulate solids, solids floating in solution like egg whites, gels, crystals, and coatings on sample containers. A gel-like material that formed in a filtered leachate from Enhanced Sludge Washing of Hanford T-104 sludge was identified as natrophosphate, Na{sub 7}(PO{sub 4}){sub 2}F{center_dot}19H{sub 2}O. A particulate material that formed in a filtered caustic leachate from Hanford SX-113 sludge contained sodium and silicon. This could be any of a host of sodium silicates in the NaOH-SiO{sub 2}-H{sub 2}O system. Acidic treatment of Hanford B-202 sludge with 1 M, 3 M, and 6 M HNO{sub 3} sequential leaching resulted in complete dissolution at 75 C, but not at ambient temperature. This treatment resulted in the formation of solids in filtered leachates. Analyses of the solids revealed that a gel material contained silica with some potassium, calcium, iron, and manganese. Two phases were embedded in the gel. One was barium sulfate. The other could not be identified, but it was determined that the only metal it contained was bismuth.

  19. Effect of Volatile Fatty Acids and Trimethylamine on Nitrification in Activated Sludge

    Eilersen, Ann Marie; Henze, Mogens; Kløft, Lene

    1994-01-01

    6 mM for isobutyric, 37 mM for n-valeric, 6 mM for isovaleric 36 mM for n-caproic acid and 3 mM for trimethylamine. IK values for nitrite oxidation were found to be 2 mM for formic, 115 mM for acetic, 68 mM for propionic, 33 mM for n-butyric, 8 mM for isobutyric, 75 mM for n-valeric, 7 mM for...

  20. Utilisation of single added fatty acids by consortia of digester sludge in batch culture

    Inocula derived from an anaerobic digester were used to study (i) their potential for methane production and (ii) the utilisation rates of different short chain fatty acids (SCFAs) by the microbial community in defined media with mono-carbon sources (formic-, acetetic-, propionic-, butyric acid) in batch culture. It could be demonstrated that the microbial reactor population could be transferred successfully to the lab, and its ability to build up methane was present even with deteriorating biogas plant performance. Therefore, this reduction in performance of the biogas plant was not due to a decrease in abundance, but due to an inactivity of the microbial community. Generally, the physico-chemical properties of the biogas plant seemed to favour hydrogenotrophic methanogens, as seen by the high metabolisation rates of formate compared with all other carbon sources. In contrast, acetoclastic methanogenesis could be shown to play a minor role in the methane production of the investigated biogas plant, although the origin of up to 66% of methane is generally suggested to be generated through acetoclastic pathway.

  1. Bioaugmentation of aerobic sludge granules with a plasmid donor strain for enhanced degradation of 2,4-dichlorophenoxyacetic acid

    Aerobic sludge granules pre-grown on glucose were bioaugmented with a plasmid pJP4 carrying strain Pseudomonas putida SM1443 in a fed-batch microcosm system and a lab-scale sequencing batch reactor (SBR) to enhance their degradation capacity to 2,4-dichlorophenoxyacetic acid (2,4-D). The fed-batch test results showed that the bioaugmented aerobic granule system gained 2,4-D degradation ability faster and maintained a more stable microbial community than the control in the presence of 2,4-D. 2,4-D at the initial concentration of about 160 mg/L was nearly completely removed by the bioaugmented granule system within 62 h, while the control system only removed 26% within 66 h. In the bioaugmented SBR which had been operated for 90 days, the seeded aerobic granules pre-grown on glucose successfully turned into 2,4-D degrading granules through bioaugmentation and stepwise increase of 2,4-D concentration from 8 to 385 mg/L. The granules showed a compact structure and good settling ability with the mean diameter of about 450 μm. The degradation kinetics of 2,4-D by the aerobic granules can be described with the Haldane kinetics model with Vmax = 31.1 mg 2,4-D/gVSS h, Ki = 597.9 mg/L and Ks = 257.3 mg/L, respectively. This study shows that plasmid mediated bioaugmentation is a feasible strategy to cultivate aerobic granules degrading recalcitrant pollutants.

  2. Reducing N2O Emission from a Domestic-Strength Nitrifying Culture by Free Nitrous Acid-Based Sludge Treatment.

    Wang, Dongbo; Wang, Qilin; Laloo, Andrew Elohim; Yuan, Zhiguo

    2016-07-19

    An increase of nitrite in the domestic-strength range is generally recognized to stimulate nitrous oxide (N2O) production by ammonia-oxidizing bacteria (AOB). It was found in this study, however, that N2O emission from a mainstream nitritation system (cyclic nitrite = 25-45 mg of N/L) that was established by free nitrous acid (FNA)-based sludge treatment was not higher but much lower than that from the initial nitrifying system with full conversion of NH4(+)-N to NO3(-)-N. Under dissolved oxygen (DO) levels of 2.5-3.0 mg/L, N2O emission from the nitritation stage was 76% lower than that from the initial stage. Even when the DO level was reduced to 0.3-0.8 mg/L, N2O emission from the nitritation stage was still 40% lower. An investigation of the mechanism showed that FNA treatment caused a shift of the stimulation threshold of nitrite on N2O emission. At the nitritation stage, the maximal N2O emission factor occurred at ∼16 mg of N/(L of nitrite). However, it increased with increasing nitrite in the range of 0-56 mg of N/L at the initial stage. FNA treatment decreased the biomass-specific N2O production rate, suggesting that the enzymes relevant to nitrifier denitrification were inhibited. Microbial analysis revealed that FNA treatment decreased the microbial community diversity but increased the abundances of AOB and denitrifiers. PMID:27294698

  3. High-rate volatile fatty acid (VFA) production by a granular sludge process at low pH.

    Tamis, J; Joosse, B M; Loosdrecht, M C M van; Kleerebezem, R

    2015-11-01

    Volatile fatty acids (VFA) are proposed platform molecules for the production of basic chemicals and polymers from organic waste streams. In this study we developed a granular sludge process to produce VFA at high rate, yield and purity while minimizing potential operational costs. A lab-scale anaerobic sequencing batch reactor (ASBR) was fed with 10 g l(-1) glucose as model substrate. Inclusion of a short (2 min) settling phase before effluent discharge enabled effective granulation and very high volumetric conversion rates of 150-300 gCOD l(-1)  d(-1) were observed during glucose conversion. The product spectrum remained similar at the tested pH range with acetate and butyrate as the main products, and a total VFA yield of 60-70% on chemical oxygen demand (COD) basis. The requirement for base addition for pH regulation could be reduced from 1.1 to 0.6 mol OH(-) (mol glucose)(-1) by lowering the pH from 5.5 to 4.5. Solids concentrations in the effluent were 0.6 ± 0.3 g l(-1) but could be reduced to 0.02 ± 0.01 g l(-1) by introduction of an additional settling period of 5 min. The efficient production of VFA at low pH with a virtually solid-free effluent increases the economic feasibility of waste-based chemicals and polymer production. Biotechnol. PMID:25950759

  4. A new insight into resource recovery of excess sewage sludge: feasibility of extracting mixed amino acids as an environment-friendly corrosion inhibitor for industrial pickling.

    Su, Wen; Tang, Bing; Fu, Fenglian; Huang, Shaosong; Zhao, Shiyuan; Bin, Liying; Ding, Jiewei; Chen, Cuiqun

    2014-08-30

    The work mainly presented a laboratory-scale investigation on an effective process to extract a value-added product from municipal excess sludge. The functional groups in the hydrolysate were characterized with Fourier transform infrared spectrum, and the contained amino acids were measured by means of an automatic amino acid analyzer. The corrosion-inhibition characteristics of the hydrolysate were determined with weight-loss measurement, electrochemical polarization and scanning electron microscopy. Results indicated that the hydrolysate contained 15 kinds of amino acid, and their adsorption on the surface could effectively inhibit the corrosion reaction of the steel from the acid medium. Polarization curves indicated that the obtained hydrolysate was a mixed-type inhibitor, but mainly restricted metal dissolution on the anode. The adsorption accorded well with the Langmuir adsorption isotherm, involved an increase in entropy, and was a spontaneous, exothermic process. PMID:25036999

  5. Identification of a novel HIV-1 TAR RNA bulge binding protein.

    Baker, B; Muckenthaler, M; Vives, E; Blanchard, A; Braddock, M; Nacken, W; Kingsman, A J; Kingsman, S M

    1994-08-25

    The Tat protein binds to TAR RNA to stimulate the expression of the human immunodeficiency virus type 1 (HIV-1) genome. Tat is an 86 amino acid protein that contains a short region of basic residues (aa49-aa57) that are required for RNA binding and TAR is a 59 nucleotide stem-loop with a tripyrimidine bulge in the upper stem. TAR is located at the 5' end of all viral RNAs. In vitro, Tat specifically interacts with TAR by recognising the sequence of the bulge and upper stem, with no requirement for the loop. However, in vivo the loop sequence is critical for activation, implying a requirement for accessory cellular TAR RNA binding factors. A number of TAR binding cellular factors have been identified in cell extracts and various models for the function of these factors have been suggested, including roles as coactivators and inhibitors. We have now identified a novel 38 kD cellular factor that has little general, single-stranded or double-stranded RNA binding activity, but that specifically recognises the bulge and upper stem region of TAR. The protein, referred to as BBP (bulge binding protein), is conserved in mammalian and amphibian cells and in Schizosaccharomyces pombe but is not found in Saccharomyces cerevisiae. BBP is an effective competitive inhibitor of Tat binding to TAR in vitro. Our data suggest that the bulge-stem recognition motif in TAR is used to mediate cellular factor/RNA interactions and indicates that Tat action might be inhibited by such competing reactions in vivo. PMID:8078772

  6. Impact of solid retention time and nitrification capacity on the ability of activated sludge to remove pharmaceuticals

    Falås, Per; Andersen, Henrik Rasmus; Ledin, Anna;

    2012-01-01

    Removal of five acidic pharmaceuticals (ibuprofen, ketoprofen, naproxen, diclofenac and clofibric acid) by activated sludge from five municipal activated sludge treatment processes, with various sludge ages and nitrification capacities, was assessed through batch experiments. The increase in aero...

  7. Dissolution and transport of coal tar compounds in fractured clay-rich residuum

    Vulava, Vijay M.; McKay, Larry D.; Broholm, Mette Martina;

    2012-01-01

    We investigated the dissolution and transport of organic contaminants from a crude coal tar mixture in a monolith of fractured clay-rich residuum. An electrolyte solution was eluted through the residuum monolith containing a small emplaced source of coal tar under biologically inhibited and mildly...... acidic conditions. Concentrations of 10 coal tar compounds, representing mono-, poly-, and heterocyclic aromatic hydrocarbons that constitute crude coal tar were monitored in the effluent over a period of 377 days. Most compounds appeared in the effluent within the first 0.1 pore volume eluted indicating...... eluted at a much slower rate. Analysis of contaminant concentrations in microcore residuum samples indicated that all 10 compounds had spread throughout the entire monolith and had diffused into the fine-grained matrix between fractures. These data suggest that the predominantly fine pore structure did...

  8. Organic acids in the rhizosphere and phytoavailability of sewage sludge-borne trace elements Ácidos orgânicos na rizosfera e fitodisponibilidade de elementos-traço originários de lodo de esgoto

    Adriana Marlene Moreno Pires; Giuliano Marchi; Maria Emília Mattiazzo; Luiz Roberto Guimarães Guilherme

    2007-01-01

    The aim of this work was to quantify low molecular weight organic acids in the rhizosphere of plants grown in a sewage sludge-treated media, and to assess the correlation between the release of the acids and the concentrations of trace-elements in the shoots of the plants. The species utilized in the experiment were cultivated in sand and sewage sludge-treated sand. The acetic, citric, lactic, and oxalic acids, were identified and quantified by high performance liquid chromatography in sample...

  9. Solids Control in Sludge Pretreatment

    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

  10. Solids Control in Sludge Pretreatment

    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.

  11. Combinations of coal tar with polyurethanes

    Riberi, B. (Bayer A.G., Leverkusen (Germany, F.R.))

    1977-01-01

    Coatings based on polyurethanes have gained world-wide reputation in shipbuilding. Apart from light-fast and weatherproof coating varnishes, systems for corrosion protection and tar combinations are increasingly used. The fast hardening of polyurethane/coal tar combinations makes it possible to apply several layers in one day. The NCO/ON reaction takes place also at temperatures near the freezing point, so that this coating material can be used throughout the year. The special tars available for combination with synthetic resins are suitable also for polyurethane/coal tar combinations. Their service life is sufficiently long even without pretreatment of the tar. Polyurethane/coal tar combinations can be used in outside-current systems. Their behaviour is excellent in tests with a potential of up to -1250 mV (Cu/CuSO/sub 4/). Using polyisocyanate prepolymers, one-component varnishes harden with air moisture and with a high stability on storage. Using liquid polyisocyanates and low-viscosity tars, solvent-free coatings are obtained.

  12. Cancer fear over coal tar products

    NONE

    1995-01-01

    Discusses a report by Dutch researchers which suggests that the regular use of coal tar shampoos may significantly increase the risk of cancer due to the high levels of polynuclear aromatic hydrocarbons (PAHs) in the products. The PAH exposure of volunteers using a coal tar anti-dandruff shampoo was studied by measuring the amount of hydroxypyrene, a PAH breakdown product in their urine. Volunteers who had used the shampoo excreted high levels of hydroxypyrene the day after exposure. Excretion by the control group using a non-coal tar anti-dandruff shampoo remained constant. 1 ref., 1 fig.

  13. Coal tar: past, present and future

    Thami, G.P.; Sarkar, R. [Government Medical College & Hospital, Chandigarh (India). Dept. of Dermatology & Venerology

    2002-03-01

    Crude coal tar has been used in the treatment of dermatoses for many decades. In the last few years its use has been limited to skin diseases such as psoriasis and chronic dermatitis. Newer topical modalities for psoriasis are being used increasingly for treatment, but have failed to replace crude coal tar as a first-line treatment of psoriasis. The authors review the pharmacology, chemistry and use of crude coal tar in order to reappraise its role as a therapeutic agent in dermatology.

  14. Thermophilic anaerobic co-digestion of sewage sludge with grease waste: Effect of long chain fatty acids in the methane yield and its dewatering properties

    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

  15. Tracking the composition and transformation of humic and fulvic acids during vermicomposting of sewage sludge by elemental analysis and fluorescence excitation-emission matrix.

    Zhang, Jie; Lv, Baoyi; Xing, Meiyan; Yang, Jian

    2015-05-01

    Sewage sludge (T1) and the mixture of sewage sludge and cattle dung (T2) were vermicomposted with Eisenia fetida, respectively. The transformation of humic acid (HA) and fulvic acid (FA) extracted from these two treatments were evaluated by a series of chemical and spectroscopic methods. Results indicated that the vermicomposting decreased pH, TOC, and C/N ratio, and increased EC, total extractable C, and HA contents. The FA content in treatment T1 was increased significantly, and only slight increasing was observed in treatment T2. Moreover, vermicomposting decreased H content, C/N ratio, proteinaceous and carbohydrates components, and increased the N content, C/H ratio, aromatic compounds and polycondensation structures in HA and FA. In addition, fluorescence spectra and fluorescence regional integration indicated that protein-like groups were degraded and HA compounds were formed. Furthermore, the addition of cattle dung enhanced the humification process and improved the HA quality in spite of no significant effect on the FA. PMID:25736580

  16. Improving the mining soil quality for a vegetation cover after addition of sewage sludges: inorganic ions and low-molecular-weight organic acids in the soil solution.

    Peña, Aránzazu; Mingorance, Ma Dolores; Guzmán-Carrizosa, Ignacio; Fernández-Espinosa, Antonio J

    2015-03-01

    We assessed the effects of applying stabilized sewage sludge (SSL) and composted sewage sludge (CLV), at 5 and 10% to an acid mining soil. Limed soil (NCL) amended or not with SSL and CLV was incubated for 47 days. We studied the cations and organic and inorganic anions in the soil solution by means of ion chromatography. Liming led to big increases in Ca(2+) and SO4(2-) and to significant decreases in K(+), Mg(2+), NH4(+) and NO3(-). Addition of both organic amendments increased some cations (NH4(+), K(+), Mg(2+), Na(+)) and anions (Cl(-), NO3(-) only with CLV and PO4(3-) only with SSL) and provided a greater amount of low-molecular-weight organic acids (LMWOAs) (SSL more than CLV). Incubation led to decreases in all cations, particularly remarkable for Ca(2+) and Mg(2+) in SSL-10. A decrease in NH4(+) was associated with variations in NO2(-) and NO3(-) resulting from nitrification reactions. During incubation the LMWOAs content tended to decrease similarly to the cations, especially in SSL-10. Chemometric tools revealed a clear discrimination between SSL, CLV and NCL. Furthermore, treatment effects depended upon dose, mainly in SSL. Amendment nature and dose affect the quality of a mining soil and improve conditions for plant establishment. PMID:25506677

  17. Treating tar sands formations with dolomite

    Vinegar, Harold J.; Karanikas, John Michael

    2010-06-08

    Methods for treating a tar sands formation are described herein. The tar sands formation may include dolomite and hydrocarbons. Methods may include providing heat at less than the decomposition temperature of dolomite from one or more heaters to at least a portion of the formation. At least some of the hydrocarbon fluids are mobilized in the formation. At least some of the hydrocarbon fluids may be produced from the formation.

  18. USE OF AN EQUILIBRIUM MODEL TO FORECAST DISSOLUTION EFFECTIVENESS, SAFETY IMPACTS, AND DOWNSTREAM PROCESSABILITY FROM OXALIC ACID AIDED SLUDGE REMOVAL IN SAVANNAH RIVER SITE HIGH LEVEL WASTE TANKS 1-15

    KETUSKY, EDWARD

    2005-10-31

    This thesis details a graduate research effort written to fulfill the Magister of Technologiae in Chemical Engineering requirements at the University of South Africa. The research evaluates the ability of equilibrium based software to forecast dissolution, evaluate safety impacts, and determine downstream processability changes associated with using oxalic acid solutions to dissolve sludge heels in Savannah River Site High Level Waste (HLW) Tanks 1-15. First, a dissolution model is constructed and validated. Coupled with a model, a material balance determines the fate of hypothetical worst-case sludge in the treatment and neutralization tanks during each chemical adjustment. Although sludge is dissolved, after neutralization more is created within HLW. An energy balance determines overpressurization and overheating to be unlikely. Corrosion induced hydrogen may overwhelm the purge ventilation. Limiting the heel volume treated/acid added and processing the solids through vitrification is preferred and should not significantly increase the number of glass canisters.

  19. Gaseous fuels production from dried sewage sludge via air gasification.

    Werle, Sebastian; Dudziak, Mariusz

    2014-06-17

    Gasification is a perspective alternative method of dried sewage sludge thermal treatment. For the purpose of experimental investigations, a laboratory fixed-bed gasifier installation was designed and built. Two sewage sludge (SS) feedstocks, taken from two typical Polish wastewater treatment systems, were analysed: SS1, from a mechanical-biological wastewater treatment system with anaerobic stabilization (fermentation) and high temperature drying; and (SS2) from a mechanical-biological-chemical wastewater treatment system with fermentation and low temperature drying. The gasification results show that greater oxygen content in sewage sludge has a strong influence on the properties of the produced gas. Increasing the air flow caused a decrease in the heating value of the produced gas. Higher hydrogen content in the sewage sludge (from SS1) affected the produced gas composition, which was characterized by high concentrations of combustible components. In the case of the SS1 gasification, ash, charcoal, and tar were produced as byproducts. In the case of SS2 gasification, only ash and tar were produced. SS1 and solid byproducts from its gasification (ash and charcoal) were characterized by lower toxicity in comparison to SS2. However, in all analysed cases, tar samples were toxic. PMID:24938297

  20. SRTC Offgas Data from Formic Acid Addition to the Sludge Batch 2 Final SME Product for Redox Adjustment

    This report summarizes the offgas data collected during the Defense Waste Processing Facility (DWPF) Slurry Mix Evaporator (SME) Redox Adjustment Cycle of the Sludge Batch 2 demonstration in the Savannah River Technology Center (SRTC) Shielded Cells. The purpose of this report is to provide the DWPF with offgas data for the SME Redox Adjustment Cycle prior to a more complete report of the overall SME process

  1. A continuous pilot-scale system using coal-mine drainage sludge to treat acid mine drainage contaminated with high concentrations of Pb, Zn, and other heavy metals

    Highlights: ► Coal mine drainage sludge can effectively neutralize and treat the acidic drainage for a long time. ► We suggest that the continuous pilot system having CMDS can not only high removal efficiencies, but also high total rates for all heavy metals. ► The pilot system can have a much higher Zn(II) loading rate than other referenced systems such as wetland coupled with algal mat and anoxic limestone drain. - Abstract: A series of pilot-scale tests were conducted with a continuous system composed of a stirring tank reactor, settling tank, and sand filter. In order to treat acidic drainage from a Pb–Zn mine containing high levels of heavy metals, the potential use of coal-mine drainage sludge (CMDS) was examined. The pilot-scale tests showed that CMDS could effectively neutralize the acidic drainage due to its high alkalinity production. A previous study revealed that calcite and goethite contained in CMDS contributed to dissolutive coprecipitation and complexation with heavy metals. The continuous system not only has high removal efficiencies (97.2–99.8%), but also large total rate constants (Ktotal, 0.21–10.18 h−1) for all heavy metals. More specifically, the pilot system has a much higher Zn(II) loading rate (45.3 g m−3 day−1) than other reference systems, such as aerobic wetland coupled with algal mats and anoxic limestone drains. The optimum conditions were found to be a CMDS loading of 280 g L−1 and a flow rate of 8 L day−1, and the necessary quantity of CMDS was 91.3 g L−1 day−1, as the replacement cycle of CMDS was determined to be 70 days.

  2. Application of sequential expanded granular sludge bed reactors for biodegradation of acetate, benzoate, terephtalate and p-toluate in purified terephtalic acid production wastewater.

    Lee, Y S; Han, G B

    2016-01-01

    The anaerobic degradation of four major constituents from purified terephtalic acid production wastewater in sequential two expanded granular sludge bed (EGSB) reactors was studied. The performance of the system was evaluated in terms of chemical oxygen demand (COD) removal efficiencies, methane production, stability, granular sludge adaptability as well as reversion of bacterial inhibition. With volumetric loading rates of 1.9-25 kg-COD m(-3) d(-1) and terephtalate and p-toluate of 584-821 mg L(-1), average removal efficiencies of 97.6% and 75.2% were achieved in the EGSB reactors, respectively. In these conditions, gas production reached a total methane production rate of 0.33 L g-COD(-1) in the two-stage EGSB reactor system. The disturbance of the EGSB reactors was observed at a feed concentration above around 6.9 g-COD L(-1) because of higher influent COD concentration compared to other experiments. PMID:26513246

  3. A Study on the Sludge Solubilization by Alkaline Treatment and Electron Beam Irradiation

    Sludge is a major product in the wastewater treatment operations. The disposal of wastewater sludge which contains mainly microbial pathogens and organic compounds remains a critical problem in the world. The sludge solubilization reduces the amount of sludge for the final disposal. Moreover, it makes possible to utilize recovered organic acids from the sludge as an external carbon source in the denitrification process. In this study, we studied the sludge solubilization and E. coli sterilization by an alkaline treatment and electron beam irradiation

  4. Impact of the terminal bulges of HIV-1 cTAR DNA on its stability and the destabilizing activity of the nucleocapsid protein NCp7.

    Beltz, Hervé; Azoulay, Joel; Bernacchi, Serena; Clamme, Jean-Pierre; Ficheux, Damien; Roques, Bernard; Darlix, Jean-Luc; Mély, Yves

    2003-04-18

    Reverse transcription of HIV-1 genomic RNA to double-stranded DNA by reverse transcriptase (RT) is a critical step in HIV-1 replication. This process relies on two viral proteins, the RT enzyme and nucleocapsid protein NCp7 that has well documented nucleic acid chaperone properties. At the beginning of the linear DNA synthesis, the newly made minus-strand strong-stop DNA ((-)ssDNA) is transferred to the 3'end of the genomic RNA by means of an hybridization reaction between transactivation response element (TAR) RNA and cTAR DNA sequences. Since both TAR sequences exhibit stable hairpin structures, NCp7 needs to destabilize the TAR structures in order to chaperone their hybridization. To further characterize the relationships between TAR stability and NC-mediated destabilization, the role of the A(49) and G(52) bulged residues in cTAR DNA stability was investigated. The stability of cTAR and mutants where one or the two terminal bulges were replaced by base-pairs as well as the NCp7-mediated destabilization of these cTAR sequences were examined. Thermodynamic data indicate that the two bulges cooperatively destabilize cTAR by reducing the stacking interactions between the bases. This causes a free energy change of about 6.4 kcal/mol and seems to be critical for NC activity. Time-resolved fluorescence data of doubly labelled cTAR derivatives suggest that NC-mediated melting of cTAR ends propagates up to the 10C.A(44) mismatch or T(40) bulge. Fluorescence correlation spectroscopy using two-photon excitation was also used to monitor cTAR ends fraying by NC. Results show that NC causes a very significant increase of cTAR ends fraying, probably limited to the terminal base-pair in the case of cTAR mutants. Since the TAR RNA and cTAR DNA bulges or mismatches appear well conserved among all HIV-1 strains, the present data support the notion of a co-evolutionary relationship between TAR and NC activity. PMID:12684000

  5. An Evolved RNA Recognition Motif That Suppresses HIV-1 Tat/TAR-Dependent Transcription.

    Crawford, David W; Blakeley, Brett D; Chen, Po-Han; Sherpa, Chringma; Le Grice, Stuart F J; Laird-Offringa, Ite A; McNaughton, Brian R

    2016-08-19

    Potent and selective recognition and modulation of disease-relevant RNAs remain a daunting challenge. We previously examined the utility of the U1A N-terminal RNA recognition motif as a scaffold for tailoring new RNA hairpin recognition and showed that as few as one or two mutations can result in moderate affinity (low μM dissociation constant) for the human immunodeficiency virus (HIV) trans-activation response element (TAR) RNA, an RNA hairpin controlling transcription of the human immunodeficiency virus (HIV) genome. Here, we use yeast display and saturation mutagenesis of established RNA-binding regions in U1A to identify new synthetic proteins that potently and selectively bind TAR RNA. Our best candidate has truly altered, not simply broadened, RNA-binding selectivity; it binds TAR with subnanomolar affinity (apparent dissociation constant of ∼0.5 nM) but does not appreciably bind the original U1A RNA target (U1hpII). It specifically recognizes the TAR RNA hairpin in the context of the HIV-1 5'-untranslated region, inhibits the interaction between TAR RNA and an HIV trans-activator of transcription (Tat)-derived peptide, and suppresses Tat/TAR-dependent transcription. Proteins described in this work are among the tightest TAR RNA-binding reagents-small molecule, nucleic acid, or protein-reported to date and thus have potential utility as therapeutics and basic research tools. Moreover, our findings demonstrate how a naturally occurring RNA recognition motif can be dramatically resurfaced through mutation, leading to potent and selective recognition-and modulation-of disease-relevant RNA. PMID:27253715

  6. Sulphur K-edge XANES and acid volatile sulphide analyses of changes in chemical speciation of S and Fe during sequential extraction of trace metals in anoxic sludge from biogas reactors

    Shakeri Yekta, Sepehr; Gustavsson, Jenny; Svensson, Bo H.; Skyllberg, Ulf

    2012-01-01

    The effect of sequential extraction of trace metals on sulphur (S) speciation in anoxic sludge samples from two lab-scale biogas reactors augmented with Fe was investigated. Analyses of sulphur K-edge X-ray absorption near edge structure (S XANES) spectroscopy and acid volatile sulphide (AVS) were conducted on the residues from each step of the sequential extraction. The S speciation in sludge samples after AVS analysis was also determined by S XANES. Sulphur was mainly present as FeS (~60% o...

  7. Site-selective probing of cTAR destabilization highlights the necessary plasticity of the HIV-1 nucleocapsid protein to chaperone the first strand transfer

    Godet, Julien; Kenfack, Cyril; Przybilla, Frédéric; Richert, Ludovic; Duportail, Guy; Mély, Yves

    2013-01-01

    The HIV-1 nucleocapsid protein (NCp7) is a nucleic acid chaperone required during reverse transcription. During the first strand transfer, NCp7 is thought to destabilize cTAR, the (−)DNA copy of the TAR RNA hairpin, and subsequently direct the TAR/cTAR annealing through the zipping of their destabilized stem ends. To further characterize the destabilizing activity of NCp7, we locally probe the structure and dynamics of cTAR by steady-state and time resolved fluorescence spectroscopy. NC(11–55), a truncated NCp7 version corresponding to its zinc-finger domain, was found to bind all over the sequence and to preferentially destabilize the penultimate double-stranded segment in the lower part of the cTAR stem. This destabilization is achieved through zinc-finger–dependent binding of NC to the G10 and G50 residues. Sequence comparison further revealed that C•A mismatches close to the two G residues were critical for fine tuning the stability of the lower part of the cTAR stem and conferring to G10 and G50 the appropriate mobility and accessibility for specific recognition by NC. Our data also highlight the necessary plasticity of NCp7 to adapt to the sequence and structure variability of cTAR to chaperone its annealing with TAR through a specific pathway. PMID:23511968

  8. Effect of surfactant on hydrolysis products accumulation and short-chain fatty acids (SCFA) production during mesophilic and thermophilic fermentation of waste activated sludge: kinetic studies.

    Zhang, Peng; Chen, Yinguang; Zhou, Qi

    2010-09-01

    In the presence of surfactant sodium dodecylbenzene sulfonate (SDBS) the hydrolysis products accumulation and the short-chain fatty acids (SCFA) production during waste activated sludge fermentation under mesophilic and thermophilic conditions was compared with that at room temperature. In order to understand the mechanism of significant amounts of mesophilic and thermophilic hydrolysis products and SCFA observed in the presence of surfactant, the kinetic models at different SDBS dosages were developed. It was found that SDBS increased the mesophilic and thermophilic hydrolysis rate significantly, and the maximum specific utilization of hydrolysis products increased at low SDBS and decreased at high one. However, the observed maximum specific utilization of SCFA decreased seriously with SDBS increase. In the presence of SDBS the decay rate of acidogenic bacteria not only was lower than that in the absence of SDBS but decreased with the increase of SDBS under either mesophilic or thermophilic conditions. PMID:20409704

  9. Tar Management and Recycling in Biomass Gasification and Syngas Purification

    McCaffrey, Zach

    Removal of tars is critical to the design and operation of biomass gasification systems as most syngas utilization processing equipment (e.g. internal combustion engines, gas turbines, fuel cells, and liquid fuel synthesis reactors) have a low tolerance for tar. Capturing and disposal of tar is expensive due to equipment costs, high hazardous waste disposal costs where direct uses cannot be found, and system energy losses incurred. Water scrubbing is an existing technique commonly used in gasification plants to remove contaminants and tar; however using water as the absorbent is non-ideal as tar compounds have low or no water solubility. Hydrophobic solvents can improve scrubber performance and this study evaluated tar solubility in selected solvents using slip-streams of untreated syngas from a laboratory fluidized bed reactor operated on almond composite feedstock using both air and steam gasification. Tar solubility was compared with Hansen's solubility theory to examine the extent to which the tar removal can be predicted. As collection of tar without utilization leads to a hazardous waste problem, the study investigated the effects of recycling tars back into the gasifier for destruction. Prior to experiments conducted on tar capture and recycle, characterizations of the air and steam gasification of the almond composite mix were made. This work aims to provide a better understanding of tar collection and solvent selection for wet scrubbers, and to provide information for designing improved tar management systems for biomass gasification.

  10. IRRADIATION EFFECTS ON THE PHYSICAL CHARACTERISTICS OF SEWAGE SLUDGE

    Lee, M-J.; Lee, J-K.; Yoo, D-H.; Ho, K.

    2004-10-05

    The radiation effects on the physical characteristic of the sewage sludge were studied in order to obtain information which will be used for study on the enhancement of the sludge's dewaterability. Water contents, capillary suction time, zeta potential, irradiation dose, sludge acidity, total solid concentration, sludge particle size and microbiology before and after irradiation were investigated. Irradiation gave an effect on physical characteristics sludge. Water content in sludge cake could be reduced by irradiation at the dose of 10kGy.

  11. Genomic characterization of ribitol teichoic acid synthesis in Staphylococcus aureus: genes, genomic organization and gene duplication

    Lu Lingyi

    2006-04-01

    Full Text Available Abstract Background Staphylococcus aureus or MRSA (Methicillin Resistant S. aureus, is an acquired pathogen and the primary cause of nosocomial infections worldwide. In S. aureus, teichoic acid is an essential component of the cell wall, and its biosynthesis is not yet well characterized. Studies in Bacillus subtilis have discovered two different pathways of teichoic acid biosynthesis, in two strains W23 and 168 respectively, namely teichoic acid ribitol (tar and teichoic acid glycerol (tag. The genes involved in these two pathways are also characterized, tarA, tarB, tarD, tarI, tarJ, tarK, tarL for the tar pathway, and tagA, tagB, tagD, tagE, tagF for the tag pathway. With the genome sequences of several MRSA strains: Mu50, MW2, N315, MRSA252, COL as well as methicillin susceptible strain MSSA476 available, a comparative genomic analysis was performed to characterize teichoic acid biosynthesis in these S. aureus strains. Results We identified all S. aureus tar and tag gene orthologs in the selected S. aureus strains which would contribute to teichoic acids sythesis.Based on our identification of genes orthologous to tarI, tarJ, tarL, which are specific to tar pathway in B. subtilis W23, we also concluded that tar is the major teichoic acid biogenesis pathway in S. aureus. Further analyses indicated that the S. aureus tar genes, different from the divergon organization in B. subtilis, are organized into several clusters in cis. Most interesting, compared with genes in B. subtilis tar pathway, the S. aureus tar specific genes (tarI,J,L are duplicated in all six S. aureus genomes. Conclusion In the S. aureus strains we analyzed, tar (teichoic acid ribitol is the main teichoic acid biogenesis pathway. The tar genes are organized into several genomic groups in cis and the genes specific to tar (relative to tag: tarI, tarJ, tarL are duplicated. The genomic organization of the S. aureus tar pathway suggests their regulations are different when

  12. K Basin sludge dissolution engineering study

    Westra, A.G.

    1998-08-28

    The purpose of this engineering study is to investigate the available technology related to dissolution of the K Basin sludge in nitric acid. The conclusion of this study along with laboratory and hot cell tests with actual sludge samples will provide the basis for beginning conceptual design of the sludge dissolver. The K Basin sludge contains uranium oxides, fragments of metallic U, and some U hydride as well as ferric oxyhydroxide, aluminum oxides and hydroxides, windblown sand that infiltrated the basin enclosure, ion exchange resin, and miscellaneous materials. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be conditioned so that it meets Tank Waste Remediation System waste acceptance criteria and can be sent to one of the underground storage tanks. Sludge conditioning will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and then reacting the solution with caustic to co-precipitate the uranium and plutonium. There will be five distinct feed streams to the sludge conditioning process two from the K East (KE) Basin and three from the K West (KW) Basin. The composition of the floor and pit sludges which contain more iron oxides and sand than uranium is much different than the canister sludges which are composed of mostly uranium oxides. The sludge conditioning equipment will be designed to process all of the sludge streams, but some of the operating parameters will be adjusted as necessary to handle the different sludge stream compositions. The volume of chemical additions and the amount of undissolved solids will be much different for floor and pit sludge than for canister sludge. Dissolution of uranium metal and uranium dioxide has been studied quite thoroughly and much information is available. Both uranium metal and uranium dioxide have been dissolved on a large scale in nuclear fuel

  13. Potential contributions of asphalt and coal tar to black carbon quantification in urban dust, soils, and sediments

    Yang, Y.; Mahler, B.J.; Van Metre, P.C.; Ligouis, B.; Werth, C.J.

    2010-01-01

    Measurements of black carbon (BC) using either chemical or thermal oxidation methods are generally thought to indicate the amount of char and/or soot present in a sample. In urban environments, however, asphalt and coal-tar particles worn from pavement are ubiquitous and, because of their pyrogenic origin, could contribute to measurements of BC. Here we explored the effect of the presence of asphalt and coal-tar particles on the quantification of BC in a range of urban environmental sample types, and evaluated biases in the different methods used for quantifying BC. Samples evaluated were pavement dust, residential and commercial area soils, lake sediments from a small urban watershed, and reference materials of asphalt and coal tar. Total BC was quantified using chemical treatment through acid dichromate (Cr2O7) oxidation and chemo-thermal oxidation at 375??C (CTO-375). BC species, including soot and char/charcoal, asphalt, and coal tar, were quantified with organic petrographic analysis. Comparison of results by the two oxidation methods and organic petrography indicates that both coal tar and asphalt contribute to BC quantified by Cr2O7 oxidation, and that coal tar contributes to BC quantified by CTO-375. These results are supported by treatment of asphalt and coal-tar reference samples with Cr2O7 oxidation and CTO-375. The reference asphalt is resistant to Cr2O7 oxidation but not to CTO-375, and the reference coal tar is resistant to both Cr2O7 oxidation and CTO-375. These results indicate that coal tar and/or asphalt can contribute to BC measurements in samples from urban areas using Cr2O7 oxidation or CTO-375, and caution is advised when interpreting BC measurements made with these methods. ?? 2010 Elsevier Ltd.

  14. Electrodialytic removal of cadmium from wastewater sludge

    Jakobsen, M. R.; Fritt-Rasmussen, Janne; Nielsen, S.;

    2004-01-01

    /solid (ml/g fresh sludge) ratio was between 1.4 and 2. Three experiments were performed where the sludge was suspended in distilled water, citric acid or HNO"3. The experimental conditions were otherwise identical. The Cd removal in the three experiments was 69, 70 and 67%, respectively, thus the removal...

  15. Activated Sludge.

    Saunders, F. Michael

    1978-01-01

    Presents the 1978 literature review of wastewater treatment. This review covers: (1) activated sludge process; (2) process control; (3) oxygen uptake and transfer; (4) phosphorus removal; (5) nitrification; (6) industrial wastewater; and (7) aerobic digestion. A list of 136 references is also presented. (HM)

  16. Effect of influent organic content on digested sludge extracellular polymer content and dewaterability

    Houghton, Jennifer I.; Stephenson, Tom

    2002-01-01

    The organic composition of the feed sludge to six laboratory-scale anaerobic digesters was adjusted by substituting a proportion of the primary sludge for glucose or propionic acid solution. Substitution with glucose caused an increase in the microbial extracellular polymer (ECP) content of the digested sludge, which altered the particle size distribution of the sludge and made the sludge more difficult to dewater. Substitution with propionic acid gave similar results to the control. The relat...

  17. Effects of liming an acid soil amended with sewage sludge enriched with Cd, Cu, Ni, and Zn on yield and Cd content of wheat grain

    Bingham, F.T. (Univ. of California, Riverside); Page, A.L.; Mitchell, G.A.; Strong, J.E.

    1979-04-01

    An acid soil (pH 5.2) was treated +- lime and 1% sewage sludge enriched with three concentrations each of Cd, Zn, Cu, and Ni in a 3/sup 4/ complete factorial design experiment (81 treatments +- lime). These treated soils were placed in pots and cropped with wheat (Triticum aestivum L.). Analysis of variance revealed significant main effects on grain yield from all metal additions to the acid soil and from Cd and Cu only in the limed soil. Significant main effects on the concentration of Cd in grain occurred with all metals added in the limed soil, but only from Cd, Zn, and Ni on the acid soil. Significant multiple metal interactions occurred in all cases. Multiple regression equations were developed for estimating grain yield and Cd content from soil metal additions and saturation extract metal content. Grain Cd concentrations were highly correlated with soil metal additions (R/sup 2/ = 0.978 and 0.988 for limed and unlimed soils, respectively) and saturation extract metals (R/sup 2/ = 0.879 and 0.950 for limed and unlimed soils). The best fit equations were used to calculate metal equivalent values for soil metals added (SME) which were then used to develop regression equations and graphs relating grain yield to SME.

  18. Leachability of heavy metals from solidified sludge

    ZHANG HuYuan; WANG Bao; DONG XingLing; FENG Lei; FAN ZhiMing

    2009-01-01

    Solidified sludge undergoes progressive depletion of the alkalinity materials under natural weathering condition and releases out of heavy metals. The leaching of heavy metals from solidified sewage sludge was studied by acid neutralization capacity (ANC) test and flow-through leaching test. The results of ANC test showed that heavy metals release at high concentration when the pH of extract lowers than 6. The disintegration of solidified sludge and the transformation of heavy metals are the main reasons for the resolubilisation of contaminants. Flow-through leaching test indicated that leaching of heavy metals from solidified sludge occurs in a slow way. A mathematical model has been developed to predict the stabilization time of heavy metals in solidified sludge. The research results showed that decreasing hydraulic conductivity is more important than cement addition for controlling the release of heavy metals from solidified sludge.

  19. Reclamation of copper-contaminated soil using EDTA or citric acid coupled with dissolved organic matter solution extracted from distillery sludge

    Soil washing using a strong chelating agent is a common practice for restoring contaminated soils, but significant soil fertility degradation and high operation costs are the major disadvantages. Washing soil with a dissolved organic matter (DOM) solution has been identified as a method that can moderate the loss of nutrients in the soil and enhance metal removal. The DOM solutions were extracted from waste sludge obtained from a local whisky distillery. Single chelating washing and chelate-DOM washing were carried out using ethylenediaminetetraacetic acid (EDTA), citric acid, and DOM solutions to remediate highly Cu-contaminated soil. Two-phase washing using 0.34 M citric acid and then 1500 mg L−1 DOM solution (pH 8.5) was found to be most favorable for the soil. With this treatment, 91% Cu was removed from the topsoil; the organic matter, cation exchange capacity, plant-available nitrogen, and available phosphate content increased by 28.1%, 103%, 17.7%, and 422%, respectively. -- Highlights: •We employ dissolved organic matter (DOM) solution to partially substitute EDTA or citric acid for soil washing. •Moderately-contaminated subsoil can be successfully remediated by sequential DOM washing. •Soil fertility deteriorates if soil is washed with EDTA or citric acid alone. •The loss of soil fertility has been reduced by performing two-phase the chelate-DOM washing. -- Washing the soil with the two-phase chelate-DOM method could remove quantities of Cu and reserve most of fertility in soil

  20. Improved production of short-chain fatty acids from waste activated sludge driven by carbohydrate addition in continuous-flow reactors: Influence of SRT and temperature

    Highlights: • SRT or temperature increase benefited the hydrolysis of fermentation substrates. • SCFAs, especially propionic acid, accumulated most at SRT 8 d and 37 °C. • The activities of key enzymes were in accordance with SCFAs production. • The ratio of Bacteria to Archaea was improved at SRT 8 d and 37 °C. - Abstract: During anaerobic fermentation of waste activated sludge (WAS), the production of short-chain fatty acids (SCFAs), especially propionic acid which is considered as the most preferred carbon source for enhanced biological phosphorus removal, can be improved by controlling the suitable mass ratio of carbon to nitrogen (C/N) and pH in batch mode. In this study the influences of solids retention time (SRT) and temperature on WAS hydrolysis and acidification in the continuous-flow systems in which the C/N ratio of WAS was modified by carbohydrate addition were investigated. Experimental results showed that the increase of SRT and temperature in a pertinent range benefited the hydrolysis of fermentation substrates and the accumulation of SCFAs, and SRT 8 d and temperature 37 °C were the most preferred conditions for the production of SCFAs, especially propionic acid. As there were more consumption of protein and carbohydrate and less production of methane at SRT 8 d and temperature 37 °C, more SCFAs were accumulated. Also, both the activities of key hydrolases and acid-forming enzymes and the ratio of acidogenic bacteria to methanogens showed good agreements with SCFAs production

  1. Nigeria to step up tar sands activity

    1987-03-01

    The Nigerian government has directed its Ministry of Mines, Power and Steel to assume responsibility for the exploration and exploitation of tar sands deposits in Bendel, Ondo and Oyo States. The directive resulted from a survey report by the University of Ife's geological consultancy unit on bituminous sand deposits in the area. The statement said the government was satisfied that there were large commercial quantities of the sands in the three states. The survey had reported that Nigeria could recover between 31 and 40 billion barrels of heavy crude from the tar sand deposits. Exploration for hydrocarbons is currently going on in Anambra and Lake Chad basins as well as the Benue Trough. Apart from the Nigerian National Petroleum Corporation, Shell Petroleum and Gulf Oil have begun exploration activities in the Ondo area. Meanwhile, Nigeria has had to import heavy crude from Venezuela, for processing at the Kaduna refinery.

  2. Confirmation Run of the DWPF SRAT Cycle Using the Sludge-Only Flowsheet with Tank 40 Radioactive Sludge and Frit 200 in the Shielded Cells Facility

    Fellinger, T.L.

    2002-08-29

    Several basic data reports have been issued concerning the recent demonstration of the Defense Waste Processing Facility (DWPF) Sludge Receipt and Adjustment Tank (SRAT) Cycle and Slurry Mix Evaporator (SME) Cycle, conducted at the Savannah River Technology Center (SRTC). The SRTC demonstration was completed using the DWPF ''Sludge-Only'' flowsheet with washed Tank 40 sludge slurry (Sludge Batch 2 or Macrobatch 3) in the Shielded Cells facility. The DWPF ''Sludge-Only'' flowsheet calls for processing radioactive sludge slurry using nitric acid, concentrated formic acid, and frit 200.

  3. Ascorbic acid, β-carotene, sugars, phenols, and heavy metals in sweet potatoes grown in soil fertilized with municipal sewage sludge.

    Antonious, George F; Dennis, Sam O; Unrine, Jason M; Snyder, John C

    2011-01-01

    Municipal sewage sludge (MSS) used for land farming typically contains heavy metals that might impact crop quality and human health. A completely randomized experimental design with three treatments (six replicates each) was used to monitor the impact of mixing native soil with MSS or yard waste (YW) mixed with MSS (YW +MSS) on: i) sweet potato yield and quality; ii) concentration of seven heavy metals (Cd, Cr, Mo, Cu, Zn, Pb, and Ni) in sweet potato plant parts (edible roots, leaves, stem, and feeder roots); and iii) concentrations of ascorbic acid, total phenols, free sugars, and β-carotene in sweet potato edible roots at harvest. Soil samples were collected and analyzed for total and extractable metals using two extraction procedures, concentrated nitric acid (to extract total metals from soil) as well as CaCl₂ solution (to extract soluble metals in soil that are available to plants), respectively. Elemental analyses were performed using inductively coupled plasma mass spectrometry (ICP-MS). Overall, plant available metals were greater in soils amended with MSS compared to control plots. Concentration of Pb was greater in YW than MSS amendments. Total concentrations of Pb, Ni, and Cr were greater in plants grown in MSS+YW treatments compared to control plants. MSS+YW treatments increased sweet potato yield, ascorbic acid, soluble sugars, and phenols in edible roots by 53, 28, 27, and 48%, respectively compared to plants grown in native soil. B-carotene concentration (157.5 μg g⁻¹ fresh weight) was greater in the roots of plants grown in MSS compared to roots of plants grown in MSS+YW treatments (99.9 μg g⁻¹ fresh weight). Concentration of heavy metals in MSS-amended soil and in sweet potato roots were below their respective permissible limits. PMID:21207309

  4. Inflation Persistence in Nepal: A TAR Representation

    T.P. Koirala Ph.D.

    2012-01-01

    This paper investigates inflation persistence under Threshold Autoregressive (TAR) model motivated by the fact that inflation in Nepal goes through different degrees of persistence based on various regime shifts. Using monthly time series of the Consumer Price Index (CPI) from 1998:01 to 2011:12, the presence of dynamic adjustment of inflation between high inflation and low inflation regimes defined by threshold inflation reveals non-linear behavior of inflation. A degree of low persistency i...

  5. Enhancing Volatile Fatty Acid by anaerobic digestion using municipal sludge combined with multiple organics%污泥联合不同有机质对厌氧发酵产酸的影响

    李骥延

    2016-01-01

    This paper studied the process of three main organic components(carbohydrates,proteins,lipids)anaerobic digestion with municipal sludge to inhancing Volatile Fatty Acid(VFA)product. According to the text,VFA achieves maximum production when anaerobic digestion com-bined with protein,the maximum yield reaches 14. 52 g/ L and 43. 47% productivity,increasing 218% and 59% respectively compared to sludge solo anaerobic digestion. Sludge combined with lipid produce only 39% yield of VFA compared to sludge solo anaerobic digestion.%研究了城市有机垃圾的三种主要成分(碳水化合物,蛋白质,脂质)与市政污泥联合厌氧发酵产酸的过程,试验结果表明,蛋白类有机质能大幅提高厌氧发酵效率,其后期产酸量达到14.52 g/ L,挥发酸产率43.47%,分别比污泥单独厌氧发酵提高218%和59%;污泥联合脂质厌氧发酵产酸量最低,仅为单独厌氧发酵产酸量的39%。

  6. Reduction of Ammonia Volatilization through Mixing Urea with Humic and Fulvic Acids isolated from Palm Oil Mill Effluent Sludge

    Shamsuddin Rosliza

    2009-01-01

    Full Text Available Problem statement: Ammonia volatilization from surface-applied urea may be substantial but it is possible to control it by mixing urea with acidic substances such as Humic Acids (HA and Fulvic Acids (FA. The objective of this study was to compare the effects of urea-HA, urea-FA, urea-acidified (HA+FA mixtures on ammonia loss, soil pH, soil exchangeable ammonium and available nitrate accumulation compared to urea alone. Approach: The effects of urea amended with or without HA and FA were evaluated in a laboratory condition using a closed-dynamic air flow system. Ammonia loss, soil pH, soil exchangeable ammonium and available nitrate were determined using standard procedures. Results: Humic acid alone was not effective in controlling ammonia volatilization even though ammonium retention was found to be significantly higher compared to urea alone. Fulvic acid significantly reduced ammonia volatilization by 50% compared to urea alone. It also caused the highest retention of soil exchangeable ammonium and available nitrate. However, there was no ammonia volatilization with acidified HA and FA. Ammonium and nitrate accumulation for FA was better than acidified HA and FA. Ammonia loss could be reduced by improving ammonium retention. It must be stressed that results obtained in the incubation experiment using an acidic (pHwater 6.32 soil of Typic Paleudults (Bekenu series may only be applicable to similar acid soils. Conclusion: Urea amended with HA or HA and FA significantly reduced ammonia loss. The outcome of this study might be contributed to the improvement of urea N use efficiency as well as reducing environmental pollution.

  7. Enhancement of volatile fatty acid production by co-fermentation of food waste and excess sludge without pH control: The mechanism and microbial community analyses.

    Wu, Qing-Lian; Guo, Wan-Qian; Zheng, He-Shan; Luo, Hai-Chao; Feng, Xiao-Chi; Yin, Ren-Li; Ren, Nan-Qi

    2016-09-01

    The study provided a cost-effective and high-efficiency volatile fatty acid (VFA) production strategy by co-fermentation of food waste (FW) and excess sludge (ES) without artificial pH control. VFA production of 867.42mg COD/g-VS was obtained under the optimized condition: FW/ES 5, solid retention time 7d, organic loading rate 9g VS/L-d and temperature 40°C. Mechanism exploration revealed that the holistic biodegradability of substrate was greatly enhanced, and proper pH range (5.2-6.4) was formed by the high buffering capacity of the co-fermentation system itself, which effectively enhanced hydrolysis yield (63.04%) and acidification yield (83.46%) and inhibited methanogenesis. Moreover, microbial community analysis manifested that co-fermentation raised the relative abundances of hydrolytic and acidogenic bacteria including Clostridium, Sporanaerobacter, Tissierella and Bacillus, but suppressed the methanogen Anaerolineae, which also facilitated high VFA production. These results were of great guiding significance aiming for VFA recovery from FW and ES in large-scale. PMID:27289056

  8. Response surface optimization of acid red 119 dye from simulated wastewater using Al based waterworks sludge and polyaluminium chloride as coagulant.

    Moghaddam, S Sadri; Moghaddam, M R Alavi; Arami, M

    2011-04-01

    In this research, the performance of Polyaluminium Chloride (PAC) and Polyaluminium Chloride sludge (PACS) as coagulants for acid red 119 (AR119) dye removal from aqueous solutions were compared. The sample of PACS was collected from "Baba Sheikh Ali" water treatment plant (Isfahan, Iran) where PAC is used as a coagulant in the coagulation/flocculation process. A response surface methodology was applied to evaluate the simple and combined effects of the operating variables including initial pH, coagulant dosage and initial dye concentration and to optimize the operating conditions of the treatment process. Results reveal that the optimal conditions for dye removal were initial pH 3.42, coagulant dosage of 4.55 g dried PACS/L and initial dye concentration of 140 mg/L for PACS, while the optimal initial pH, coagulant dosage and initial dye concentration for PAC were 3.8, 57 mg/L and 140 mg/L, respectively. Under these optimal values of process parameters, the dye removal efficiency of 94.1% and 95.25% was observed for PACS and PAC, respectively. Although lower amount of PAC in comparison with PACS was needed for specific dye removal, the reuse of PACS as a low-cost material can offer some advantages such as high efficiency for AR119 dye removal and economic savings on overall water and wastewater treatment plant operation costs. PMID:21216522

  9. Pretreatment of neutralized cladding removal waste sludge

    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)

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

    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

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

    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.

  12. TREATMENT OF ACID MINE DRAINAGE: I. EQUILIBRIUM BIOSORPTION OF ZINC AND COPPER ON NON-VIABLE ACTIVATED SLUDGE

    Biosorption is potentially attractive technology for treament of acid mine drainage for separation/recovery of metal ions and mitigation of their toxicity to sulfate reducing bacteria. This study describes the equilibrium biosorptio of Zn(II) and CU(II) by nonviable activated slu...

  13. Diffusion of coal-tar compounds in natural clayey till

    Broholm, Mette M.; Broholm, Kim; Arvin, Erik

    2000-01-01

    The diffusion of coal-tar compounds in natural clayey till was studied. Diffusion profile data strongly indicated highly non-linear sorption isotherms with significantly stronger sorption of the most strongly sorbing compounds, in contrast to weaker sorption of the less strongly sorbing compounds......, at high solute concentrations. The observed diffusion profiles have important implications with respect to migration of coal-tar and dissolved coal-tar compounds in fractured clayey till....

  14. Effects of various pretreatments on biohydrogen production from sewage sludge

    XIAO BenYi; LIU JunXin

    2009-01-01

    The sewage sludge of wastewater treatment plant is a kind of biomass which contains many organics,mainly carbohydrates and proteins. Four pretreatments, acid pretreatment, alkaline pretreatment,thermal pretreatment and ultrasonic pretreatment, were used to enhance biohydrogen production from sewage sludge. The experimental results showed that the four pretreatments could all increase the soluble chemical oxygen demand (SCOD) of sludge and decrease the dry solid (DS) and volatile solid(VS) because the pretreatments could disrupt the floc structure and even the microbial cells of sludge.The results of batch anaerobic fermentation experiments demonstrated that all of the four pretreat-ments could select hydrogen-producing microorganisms from the microflora of sludge and enhance the hydrogen production. The hydrogen yield of the alkaline pretreated sludge at initial pH of 11.5 was the maximal (11.68 mL H2/g VS) and that of the thermal pretreated sludge was the next (8.62 mL H2/g VS).The result showed that the hydrogen yield of pretreated sludge was correlative with its SCOD. The hydrogen yields of acid pretreated sludge and alkaline pretreated sludge were also influenced by their initial pH. No methane could be detected in the anaerobic fermentation of alkaline pretreated sludge and thermal pretreated sludge, which suggested that these pretreatments could fully inhibit the activity of methanogens. The volatile fatty acids (VFA) production in anaerobic fermentation of alkaline pretreated sludge was the maximum and the next is that of thermal pretreated sludge.

  15. VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS

    Eric M. Suuberg; Vahur Oja

    1997-07-01

    This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization which have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.

  16. Evaluation of surfactant flushing for remediating EDC-tar contamination

    Liang, Chenju; Hsieh, Cheng-Lin

    2015-06-01

    Ethylene dichloride tar (EDC-tar) is a dense non-aqueous phase liquid (DNAPL) waste originated from the process of vinyl chloride production, with major constituents including chlorinated aliphatic and aromatic hydrocarbons. This study investigated the feasibility of Surfactant Enhanced Aquifer Remediation (SEAR) for treating EDC-tar contaminated aquifers. Initial experiments explored the potential to enhance the apparent solubility of EDC-tar using single or mixed surfactants. The results showed that an aqueous solution mixed anionic and non-ionic surfactants (i.e., SDS/Tween 80) exhibited higher EDC-tar apparent solubility and lower surface tension than other surfactant systems tested. Additionally, alkaline pH aids in increasing the EDC-tar apparent solubility. In column flushing experiments, it was seen that the alkaline mixed SDS/Tween 80 solution showed better removal of pure EDC-tar from silica sand porous media. Furthermore, separation of EDC-tar in the surfactant solution was conducted employing a salting-out effect. Significant separation of DNAPL was observed when 13 wt.% or more NaCl was added to the solution. Overall, this study evaluates the feasibility of using SEAR for remediating EDC-tar contaminated subsurface soil and groundwater.

  17. Evaluation of surfactant flushing for remediating EDC-tar contamination.

    Liang, Chenju; Hsieh, Cheng-Lin

    2015-01-01

    Ethylene dichloride tar (EDC-tar) is a dense non-aqueous phase liquid (DNAPL) waste originated from the process of vinyl chloride production, with major constituents including chlorinated aliphatic and aromatic hydrocarbons. This study investigated the feasibility of Surfactant Enhanced Aquifer Remediation (SEAR) for treating EDC-tar contaminated aquifers. Initial experiments explored the potential to enhance the apparent solubility of EDC-tar using single or mixed surfactants. The results showed that an aqueous solution mixed anionic and non-ionic surfactants (i.e., SDS/Tween 80) exhibited higher EDC-tar apparent solubility and lower surface tension than other surfactant systems tested. Additionally, alkaline pH aids in increasing the EDC-tar apparent solubility. In column flushing experiments, it was seen that the alkaline mixed SDS/Tween 80 solution showed better removal of pure EDC-tar from silica sand porous media. Furthermore, separation of EDC-tar in the surfactant solution was conducted employing a salting-out effect. Significant separation of DNAPL was observed when 13 wt.% or more NaCl was added to the solution. Overall, this study evaluates the feasibility of using SEAR for remediating EDC-tar contaminated subsurface soil and groundwater. PMID:25941757

  18. Analysis of Organic and Inorganic Contaminants in Dried Sewage Sludge and By-Products of Dried Sewage Sludge Gasification

    Sebastian Werle

    2014-01-01

    Full Text Available Organic and inorganic contaminants in sewage sludge may cause their presence also in the by-products formed during gasification processes. Thus, this paper presents multidirectional chemical instrumental activation analyses of dried sewage sludge as well as both solid (ash, char coal and liquid (tar by-products formed during sewage gasification in a fixed bed reactor which was carried out to assess the extent of that phenomenon. Significant differences were observed in the type of contaminants present in the solid and liquid by-products from the dried sewage sludge gasification. Except for heavy metals, the characteristics of the contaminants in the by-products, irrespective of their form (solid and liquid, were different from those initially determined in the sewage sludge. It has been found that gasification promotes the migration of certain valuable inorganic compounds from sewage sludge into solid by-products which might be recovered. On the other hand, the liquid by-products resulting from sewage sludge gasification require a separate process for their treatment or disposal due to their considerable loading with toxic and hazardous organic compounds (phenols and their derivatives.

  19. Biodiesel production from municipal secondary sludge.

    Kumar, Manish; Ghosh, Pooja; Khosla, Khushboo; Thakur, Indu Shekhar

    2016-09-01

    In the present study, feasibility of biodiesel production from freeze dried sewage sludge was studied and its yield was enhanced by optimization of the in situ transesterification conditions (temperature, catalyst and concentration of sludge solids). Optimized conditions (45°C, 5% catalyst and 0.16g/mL sludge solids) resulted in a 20.76±0.04% biodiesel yield. The purity of biodiesel was ascertained by GC-MS, FT-IR and NMR ((1)H and (13)C) spectroscopy. The biodiesel profile obtained revealed the predominance of methyl esters of fatty acids such as oleic, palmitic, myristic, stearic, lauric, palmitoleic and linoleic acids indicating potential use of sludge as a biodiesel feedstock. PMID:27240231

  20. Environmental fate mechanisms influencing biological degradation of coal-tar derived polynuclear aromatic hydrocarbons in soil systems

    This paper discusses biodegradation, a technically viable and cost effective approach for the reduction and immobilization of polynuclear aromatic hydrocarbons (PAH) present in contaminated soils and sludges associated with coal-tar derived processes. While it is widely reported and accepted that PAH biodegradation in soil systems does occur, the specific controlling mechanisms are not entirely understood. One common observation among published reports is that the more soluble, lower molecular weight PAH compounds are biodegraded to a greater extent than the less soluble, higher molecular weight PAHs. The rate and extent to which PAHs are removed form soil/sludges is influenced by the combined and simultaneously occurring effects of volatilization, sorption and biological oxidation. The degree to which each of these three environmental fate mechanisms occurs is mainly influenced by the physical/chemical characteristics of the contaminated media, the physical/chemical characteristics of the specific PAH compounds, and the design and operation of the particular biological treatment process

  1. Chemical modeling of waste sludges

    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.

  2. Distributions of 14 elements on 63 absorbers from three simulant solutions (acid-dissolved sludge, acidified supernate, and alkaline supernate) for Hanford HLW Tank 102-SY

    As part of the Hanford Tank Waste Remediation System program at Los Alamos, we evaluated 63 commercially available or experimental absorber materials for their ability to remove hazardous components from high-level waste (HLW). These absorbers included cation and anion exchange resins, inorganic exchangers, composite absorbers, and a series of liquid extractants sorbed on porous support-beads. We tested these absorbers with three solutions prepared to simulate acid-dissolved sludge (pH 0.6), acidified supernate (pH 3.5), and alkaline supernate (pH 13.9) from underground storage tank 102-SY at the Hanford Reservation near Richland, Washington. To these simulants we added the appropriate radionuclides and used gamma spectrometry to measure fission products (Ce, Cs, Sr, Tc, and Y), actinides (U, Pu, and Am), and matrix elements (Cr, Co, Fe, Mn, Zn, and Zr). For each of more than 2500 element/absorber/solution combinations, we measured distribution coefficients for dynamic contact periods of 30 min, 2 h, and 6 h to obtain information about sorption kinetics. Because we measured the sorption of many different elements, the tabulated results indicate those elements most likely to interfere with the sorption of elements of greater interest. On the basis of nearly 7500 measured distribution coefficients, we determined that many of these absorbers appear suitable for processing HLW. This study supersedes the previous version of LA-12654, in which results attributed to a solution identified as an alkaline supernate simulant were misleading because that solution contained insufficient hydroxide

  3. Textural characteristics of the Nigerian tar sands

    Enu, E. I.

    1985-05-01

    Extensive tar sands with reserves of about 41 billion barrels of oil are known to occur in Cretaceous terrigenous sediments in Ondo and Ogun States of Nigeria. The hydrocarbon occurs in two predominantly sandy zones separated by an 8 m thick oil shale. The lower (Horizon Y) is mostly quartz sand, 3-26 m thick. It shows an upward fining of grains and increased consolidation updip. The upper Horizon X is 10-22 m of sandstone with interbedded shales and siltstones. The sands are loosely consolidated. Cementing material is lacking, the grains being held together largely by the tarry oil. Porosity is about 30% and mean oil saturation in both zones is 12%. The recorded clay content (2-7%) is considerably lower than the average for Athabasca, Canada (10-25%) and may enhance the settling properties of the tailing ponds. The sands are water-wet, fine- to medium-grained, moderately well sorted, mesokurtic and positively skewed to near symmetrical. The Nigerian tar sands compare closely with the Athabasca sands in all the above textural parameters. They would thus be expected to show identical response to mining processing, except for the influence of higher ground-water table and the high humidity and ambient temperatures in Nigeria.

  4. The extraction of bitumen from western tar sands

    Oblad, A.G.; Bunger, J.W.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1990-07-01

    Topics discussed include: characterization of bitumen impregnated sandstone, water based tar sand separation technology, electrophoretic characterization of bitumen and fine mineral particles, bitumen and tar sand slurry viscosity, the hot water digestion-flotation process, electric field use on breaking water-in-oil emulsions, upgrading of bitumens and bitumen-derived liquids, solvent extraction.

  5. The extraction of bitumen from western tar sands. Annual report

    Oblad, A.G.; Bunger, J.W.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1990-07-01

    Topics discussed include: characterization of bitumen impregnated sandstone, water based tar sand separation technology, electrophoretic characterization of bitumen and fine mineral particles, bitumen and tar sand slurry viscosity, the hot water digestion-flotation process, electric field use on breaking water-in-oil emulsions, upgrading of bitumens and bitumen-derived liquids, solvent extraction.

  6. 48 CFR Appendix to Part 1252 - Tar Matrix

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Tar Matrix Appendix to Part 1252 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Pt. 1252, App. Appendix to Part 1252—Tar Matrix...

  7. Radiation stability of bitumunous oils and its tar fraction

    Full text : The radiation-chemical transformation of bituminous oil from Balakhani oil deposit and its tar fraction have been studied. The mechanism of radiation-chemical transformation of bituminous oil and its tar fraction have been established by methods of mass-spectrometry, infrared spectroscopy and chromatography. It has been shown that bituminous oils has a high radiation stability at the temperature under 50 degrees Celsius. The ratio of radiation stabilities of oil and tar fraction is 4:1. The radiation-chemical yield of decomposition of polycyclic aromatic compounds in the tar fraction changes in limits 10-2 - 10-3. It was concluded that high radiation stability of bituminous oil and its tar fraction, allows to use them as a initial raw material for production of the hydroisolation material, which can be used in conditions of influence of radiation

  8. Reductive smelting of spent lead-acid battery colloid sludge in a molten Na2CO3 salt

    Yu-jie Hu; Chao-bo Tang; Mo-tang Tang; Yong-ming Chen

    2015-01-01

    Lead extraction from spent lead–acid battery paste in a molten Na2CO3 salt containing ZnO as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, ZnO and salt dosages, were investigated in detail using single-factor experiments. The optimum conditions were determined as follows:T = 880°C;t = 60 min; Na2CO3/paste mass ratio = 2.8:1; and the ZnO dosage is equal to the stoichiometric requirement. Under the optimum conditions, the direct recovery rate of lead reached 98.14%. The re-sults suggested that increases in temperature and salt dosage improved the direct recovery rate of lead. XRD results and thermodynamic cal-culations indicated that the reaction approaches of lead and sulfur were PbSO4→Pb and PbSO4→ZnS, respectively. Sulfur was fixed in the form of ZnS, whereas the molten salt did not react with other components, serving only as a reaction medium.

  9. SLUDGE ORGANICS BIOAVAILABILITY

    Concern over the bioavailability of toxic organics that can occur in municipal sludges threatens routine land application of sludge. vailable data, however, show that concentrations of priority organics in normal sludges are low. ludges applied at agronomic rates yield chemical c...

  10. Continuous bioproduction of short-chain fatty acids from sludge enhanced by the combined use of surfactant and alkaline pH.

    Chen, Yinguang; Liu, Kun; Su, Yinglong; Zheng, Xiong; Wang, Qin

    2013-07-01

    This work reported the enhancement of continuous SCFA production from sludge by the combined use of surfactant (sodium dodecylbenzene sulfonate (SDBS)) and pH 10 (i.e., SDBS & pH 10). The maximal SCFA production (2056 mg COD/L) was achieved under the SDBS & pH 10 condition at a sludge retention time (SRT) of 12d, which was much higher than that of the blank, sole SDBS, or pH 10. The mechanisms investigation showed that the combined strategy had greater sludge solubilization, higher protein hydrolysis, and lower activity of methanogens. Fluorescence in situ hybridization analysis revealed that the abundance of bacteria was increased, whereas that of archaea was decreased by SDBS & pH 10. The excitation emission matrix fluorescence spectroscopy assay further suggested that SBDS caused protein structure change, which benefited protein hydrolysis. PMID:23685363

  11. Characterization and performance of carbonaceous materials obtained from exhausted sludges for the anaerobic biodecolorization of the azo dye Acid Orange II

    Graphical abstract: - Highlights: • Carbonaceous materials were prepared from exhausted sludge materials. • High surface area and good physicochemical properties were achieved. • Utilization of waste sludge materials and mixed anaerobic cultures were used in a continuous anaerobic UPBR system (upflow packed bed biological reactor). • Effective treatment of dye contaminated wastewater in a cheapest and environmental friendly method was demonstrated. - Abstract: This work presents the preliminary study of new carbonaceous materials (CMs) obtained from exhausted sludge, their use in the heterogeneous anaerobic process of biodecolorization of azo dyes and the comparison of their performance with one commercial active carbon. The preparation of carbonaceous materials was conducted through chemical activation and carbonization. Chemical activation was carried out through impregnation of sludge-exhausted materials with ZnCl2 and the activation by means of carbonization at different temperatures (400, 600 and 800 °C). Their physicochemical and surface characteristics were also investigated. Sludge based carbonaceous (SBC) materials SBC400, SBC600 and SBC800 present values of 13.0, 111.3 and 202.0 m2/g of surface area. Biodecolorization levels of 76% were achieved for SBC600 and 86% for SBC800 at space time (τ) of 1.0 min, similar to that obtained with commercial activated carbons in the continuous anaerobic up-flow packed bed reactor (UPBR). The experimental data fit well to the first order kinetic model and equilibrium data are well represented by the Langmuir isotherm model. Carbonaceous materials show high level of biodecolorization even at very short space times. Results indicate that carbonaceous materials prepared from sludge-exhausted materials have outstanding textural properties and significant degradation capacity for treating textile effluents

  12. Canada's toxic tar sands : the most destructive project on earth

    This document addressed the environmental problems associated with tar sands development in Alberta, with particular reference to toxicity problems associated with global warming and the impending destruction of the boreal forest. The authors cautioned that the tar sand projects are highly destructive, leaving downstream toxics equivalent to that of a massive slow motion oil spill that has the potential to poison people. Negligent oversights by the government regarding the impact of tar sands development were also discussed, with reference to toxics on site; toxics downwind; and toxics down the pipe. The report also provided information on the future of tar sands development and global warming in Canada. It included a discussion of reverse alchemy; Canada's failed climate politics; a tar sands tax; and taking responsibility. Last, the report addressed toxic enforcement, including the Fisheries Act; Canadian Environmental Protection Act; Canadian Environmental Assessment Act; and Alberta law. It was concluded that while it is a stretch to believe the tar sands can truly be sustainable, there is a great deal that can be done to clean it up. The authors recommended that new tar sands approvals should wait until certain reform elements are implemented, such as passing a real carbon cap; using dry tailings; requiring wildlife offsets; cleaning up refineries and upgraders; ensuring Aboriginal control and benefit; and having regulation and independent monitoring. 104 refs., 6 figs

  13. Final Safety Assessment of Coal Tar as Used in Cosmetics

    NONE

    2008-07-01

    Coal Tar is a semisolid by-product obtained in the destructive distillation of bituminous coal, which functions in cosmetic products as a cosmetic biocide and denaturant-antidandruff agent is also listed as a function, but this is considered an over-the-counter (OTC) drug use. In 2002, Coal Tar was reported to the Food and Drug Administration (FDA) to be used in four formulations, all of which appear to be OTC drug products. Coal Tar is monographed by the FDA as Category I (safe and effective) OTC drug ingredient for use in the treatment of dandruff, seborrhoea, and psoriasis. Coal Tar is absorbed through the skin of animals and humans and is systemically distributed. Although the Cosmetic Ingredient Review (CIR) Expert Panel believes that Coal Tar use as an antidandruff ingredient in OTC drug preparations is adequately addressed by the FDA regulations, the Panel also believes that the appropriate concentration of use of Coal Tar in cosmetic formulations should be that level that does not have a biological effect in the user. Additional data needed to make a safety assessment include product types in which Coal Tar is used (other than as an OTC drug ingredient), use concentrations, and the maximum concentration that does not induce a biological effect in users.

  14. Enhanced Lipid and Biodiesel Production from Glucose-Fed Activated Sludge: Kinetics an Microbial Community Analysis

    An innovative approach to increase biofuel feedstock lipid yields from municipal sewage sludge via manipulation of carbon:nitrogen (C:N) ratio and glucose loading in activated sludge bioreactors was investigated. Sludge lipid and fatty acid methyl ester (biodiesel) yields (% cel...

  15. 生活污水污泥制备的生物质炭对红壤酸度的改良效果及其环境风险%Amelioration Effects of Wastewater Sludge Biochars on Red Soil Acidity and Their Environmental Risk

    卢再亮; 李九玉; 姜军; 徐仁扣

    2012-01-01

    采用厌氧热解方法由采自南京市生活污水处理厂的2种污泥分别在300、500和700℃下制备生物质炭,测定了污泥和污泥生物质炭的性质和重金属含量,研究了污泥和污泥生物质炭对酸性红壤的改良效果,并探讨了污泥炭中重金属的环境风险,以考察污泥生物质炭在红壤地区农用的可行性.结果表明,污泥和污泥炭中含有一定量的碱,添加污泥和污泥炭均可提高红壤的pH值,但污泥中有机氮的矿化和铵态氮的硝化会引起红壤pH波动.90 d培养实验结束时,500和700℃下制备的污泥炭的改良效果远高于污泥.污泥和污泥炭中含有丰富盐基阳离子,添加污泥和污泥炭提高了土壤交换性钙、镁、钾和钠含量,降低了土壤交换性铝和交换性H+含量.污泥制备成生物质炭后重金属含量有所增加,但除Zn和Cd外,Cu、Pb、Ni和As含量没有超过国家标准.与污泥相比,城东污泥炭中有效态重金属含量显著降低,说明热解过程可以降低有毒重金属的活性.90 d培养实验结束后,添加江心洲污泥和污泥炭处理之间土壤有效态重金属含量差异不显著;添加城东污泥炭处理,土壤大部分重金属的有效态含量低于添加污泥处理.因此,污泥生物质炭可以用作酸性土壤改良剂,与直接添加污泥相比,污泥生物质炭没有增加土壤重金属的活性和生物有效性.%Biochars were prepared from wastewater sludge from two wastewater treatment plants in Nanjing using a pyrolysis method at 300,500 and 700℃.The properties of the biochars were measured,and their amelioration effects on the acidity of a red soil and environmental risk of application of sludge biochars were examined to evaluate the possibility of agricultural application of wastewater sludge biochars in red soils.Results indicated that incorporation of both sludge and sludge biochar increased soil pH due to the alkalinity of sludge and sludge biochar,and the

  16. USE OF THE SOIL-TAR MIXTURES IN FOREST ROADS

    Dalila C. M. Fernandes; Carlos C. Machado; Dario C. Lima; I. Jucksch; Reginaldo S. Pereira

    2002-01-01

    The purpose of this study was to analyze the engineering behavior of the soil-tar mixtures considering their application in forest road. The laboratory-testing program encompassed characterization and California bearing ratio (CBR) tests performed on soils and soil-tar mixtures. Three representative soil samples from the Viçosa, Minas Gerais State, Brazil, and tar contents of 0,25; 0,5; 1; 2; 4 and 6% in terms of dry soil mass were considered throughout the study. All the samples were compact...

  17. Spectroscopic study of the humification process during sewage sludge treatment

    Pajączkowska, J.; Sułkowska, A.; Sułkowski, W. W.; Jędrzejczyk, M.

    2003-06-01

    The aim of this work was to study the free radical transition of organic materials during the sewage treatment process. Investigations of sludge from biologic-mechanical sewage treatment plant in Sosnowiec Zagórze were carried out. The course of the humification processes during sewage treatment was studied by electron paramagnetic resonance (EPR) technique. The concentration of free radicals at each process stage and the value g were determined. Sludge samples and extracted fractions of humic acids were examined. Humic acids were extracted from sludge by means of conventional methods elaborated by Stevenson. For study of humic acids structures, besides EPR, the UV-Vis and IR spectroscopy were used.

  18. Sludge Treatment and Extraction Technology Development: Results of FY 1993 studies

    This report describes experimental results from work conducted in FY 1993 under the Sludge Treatment and Extraction Technology Development Task of the Tank Waste Remediation System (TWRS) Pretreatment Technology Development Project at Pacific Northwest Laboratory (PNL). Experiments were conducted in the following six general areas: (1) sludge washing, (2) sludge leaching, (3) sludge dissolution, (4) actinide separation by solvent extraction and extraction chromatography, (5) Sr separation by solvent extraction, and (6) extraction of Cs from acidic solution

  19. Source identification of a tar residue from Mumbai Beach

    Kadam, A; Rokade, M.A

    A tar residue from Mumbai Beach, Maharashtra, India was matched with the suspected source sample from a tanker using UV, IR and GLC techniques. Negligible differences in several ratios of UV absorbances and ratios of infrared transmittances...

  20. COLOR ASPHALT CONCRETE COATING ON POLIMER-TAR BINDER

    Zolotarev, V.; Golovenchic, S.; Oksak, S.; S. Efremov

    2005-01-01

    The possibility of receiving of color asphalt concrete on polimer-tar binder is found. Principal moments of production technology of coloured mixtures and device of asphalt concrete coating have been revealed.

  1. Application of the HTGR in tar sands oil recovery

    The study presented in this paper explored the potential application of a high-temperature gas-cooled reactor (HTGR) to supply both process steam and cogenerated electric power for tar sands oil recovery and upgrading. The raw product recovered from the tar sands is a heavy bitumen. Upgrading, which involves coking and hydrodesulfurization, produces a synthetic crude (refinable by current technology) and petroleum coke. Energy requirements by form for each process are considered. An HTGR plant could be the most economical source of steam and electric power. This paper includes a description of the HTGR plant, a heat cycle and energy balance developed for a typical commercial tar sands oil recovery operation, and a schematic field arrangement showing the coupling of the HTGR to the process. Data developed during this study include expected bitumen recovery, economic data, and a comparative assessment of the HTGR application for tar sands recovery

  2. Tar dewpoint analyser. For application in biomass gasification product gases

    This project aims at the development of an analyser for the on-line measurement of tar dewpoints in biomass product gases. The work has been executed according to the project proposal. On basis of the specifications for the tar dewpoint analyser (TDA), an existing hydrocarbon dewpoint sensor was modified and a gas conditioning section was designed for tar dewpoint measurements. Preliminary laboratory tests with the gas conditioning section and dewpoint sensor were run to investigate the performance and fouling characteristics of the dewpoint sensor and the gas conditioning section. The TDA (gas conditioning section + sensor) was tested and validated downstream the laboratory scale BFB gasifier at ECN. Tar dewpoints between 25C and 170C could successfully be measured. After finishing the tests a pre design for a commercial analyser was made. Finally, the market for the TDA was identified and segmented in R and D groups, indirect co-combustion and stand-alone biomass gasification installations

  3. Ultrasonic-assisted extraction of Cu, Zn, Ni and Cr in municipal sludge with oxalic acid and HEDTA%超声辐射协同草酸-HEDTA浸提污泥中重金属

    涂剑成; 赵庆良; 杨倩倩

    2011-01-01

    Ultrasonic was applied to enhance extraction of heavy metals in municipal sludge with oxalic acid and hydroxyethyl ethylenediamine triacetic acid (HEDTA). The effects of ultrasonic radiation time, power intensity and stirring on extraction of heavy metals were investigated. Moreover, the transformation of heavy metal speciation in municipal sludge was analyzed by the application of tessier's sequential extraction procedure. In general, the extraction ratios of Cu, Ni and Cr in sludge were improved with the increasing of ultrasonic time, power intensity and stirring, the extraction ratios of Zn had no obviously improved. After the ultrasonic-assisted chemical extraction procedure, the content of organic compounds and residue forms of Cu, Cr and Ni were decreased. However, exchangeable and carbonate compounds forms of heavy metals were dramatically increased, the speciation of Zn in sludge was hardly changed.%利用超声波辐射协同草酸—羟乙基替乙二胺三乙酸(HEDTA)浸提城市污泥中重金属Cu、Zn、Cr、Ni,研究了超声辐射时间、功率密度、搅拌作用对Cu、Zn、Cr、Ni浸出的影响,并利用Tessier连续浸提法分析了超声波协同草酸HEDTA浸提对污泥中重金属形态的影响.结果表明,随着超声时间、功率密度的增加和污泥搅动,污泥中Cu、Cr和Ni的浸提率呈上升趋势,Zn的浸提率无明显提高.污泥在超声辐射浸提处理后,Cu、Cr、Ni的有机物结合态和残渣态含量下降,金属离子可交换态和碳酸盐结合态含量有所增加,Zn的形态无明显变化.

  4. Waste-to-clean syngas: avoiding tar problems

    Bosmans, Anouk; Wasan, Shivanand; Helsen, Lieve

    2013-01-01

    Syngas from gasification of carbon-rich feedstock is used for power generation as well as for the production of synthetic fuels and commodity chemicals. Tar removal forms a major challenge in the effort to make these syngas valorisation technologies technically and commercially feasible. Tar removal methods can be divided into two categories: (1) primary methods or treatments inside the gasifier, and (2) secondary methods or hot gas cleaning after the gasifier. The most important features of ...

  5. Literature Review on Possible Alternatives to Tar for Antiskid Layers

    Xiao, Y

    2010-01-01

    In airports, there are different areas such as runways, taxiways, aprons and parking areas. For runways, good skid resistance and water drainage of the surface layer is necessary. Tar, because of its good adhesion properties and other advantages as mentioned above, is widely used in thin, high skid resistance surfaces. Tar however is toxic and carcinogenic because of its high benzene content. This material did not meet the Dutch environmental standards. In the Netherlands and many other count...

  6. Creating and maintaining a gas cap in tar sands formations

    Vinegar, Harold J. (Bellaire, TX); Karanikas, John Michael (Houston, TX); Dinkoruk, Deniz Sumnu (Houston, TX); Wellington, Scott Lee (Bellaire, TX)

    2010-03-16

    Methods for treating a tar sands formation are disclosed herein. Methods for treating a tar sands formation may include providing heat to at least part of a hydrocarbon layer in the formation from one or more heaters located in the formation. Pressure may be allowed to increase in an upper portion of the formation to provide a gas cap in the upper portion. At least some hydrocarbons are produced from a lower portion of the formation.

  7. Catalytic destruction of tar in biomass derived producer gas

    The purpose of this study is to investigate catalytic destruction of tar formed during gasification of biomass, with the goal of improving the quality of the producer gas. This work focuses on nickel based catalysts treated with alkali in an effort to promote steam gasification of the coke that deposits on catalyst surfaces. A tar conversion system consisting of a guard bed and catalytic reactor was designed to treat the producer gas from an air blown, fluidized bed biomass gasifier. The guard bed used dolomite to crack the heavy tars. The catalytic reactor was used to evaluate three commercial steam reforming catalysts. These were the ICI46-1 catalyst from Imperial Chemical Industry and Z409 and RZ409 catalysts from Qilu Petrochemical Corp. in China. A 0.5-3 l/min slipstream from a 5 tpd biomass gasifier was used to test the tar conversion system. Gas and tar were sampled before and after the tar conversion system to evaluate the effectiveness of the system. Changes in gas composition as functions of catalytic bed temperature, space velocity and steam/TOC (total organic carbon) ratio are presented. Structural changes in the catalysts during the tests are also described

  8. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, and 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments. - Coal-tar pavement sealants degrade stream invertebrate communities.

  9. USE OF THE SOIL-TAR MIXTURES IN FOREST ROADS

    Dalila C. M. Fernandes

    2002-01-01

    Full Text Available The purpose of this study was to analyze the engineering behavior of the soil-tar mixtures considering their application in forest road. The laboratory-testing program encompassed characterization and California bearing ratio (CBR tests performed on soils and soil-tar mixtures. Three representative soil samples from the Viçosa, Minas Gerais State, Brazil, and tar contents of 0,25; 0,5; 1; 2; 4 and 6% in terms of dry soil mass were considered throughout the study. All the samples were compacted at the Standard AASHTO compaction effort. Data support that: (i addition of tar contributed to improve the mechanical engineering response of the tested soils, for some treatments, in comparison with the plain soils; (ii curing time influences the mechanical response of the soil-tar mixtures; (iii although it was observed mechanical improvement of the soil-tar mixtures comparing to the plain soils, it was not reached the Brazilian National Road Engineering Office (DNER minimal stability requirements for sub-base layers of flexible pavements.

  10. Characterization and treatment of tars and biomass gasifiers

    Baker, E.G.; Brown, M.D.; Elliott, D.C.; Mudge, L.K.

    1988-08-01

    Biomass gasification and pyrolysis have the potential to make a significant impact on energy supplies in the United States and have demonstrated their commercial potential in many projects around the country. The environmental aspects of biomass gasification need to be defined to assure that the technology makes its maximum impact on energy supplies. One area that needs further development is characterization and treatment of the tar byproduct from gasifiers and pyrolyzers. This paper examines the effect of the type of gasifier/pyrolyzer and the processing conditions on the yield and properties of tars and condensates. End use limitations for tars are discussed. Wet scrubbing is the most common method of tar removal from gases. The scrub liquor will require treatment to remove organics before it can be disposed. Pacific Northwest Laboratory (PNL) is developing a catalytic tar destruction process that will treat the hot, raw gas from the gasifier and convert the tars to gas. The process increases the gas yield and cold gas efficiency of the gasification process, produces a clean gas that can be used for many applications, and produces a clean condensate that can be disposed with minimal treatment. 10 refs., 2 figs., 1 tab.

  11. Biodegradation of liquid coal tar in an aqueous bioreactor

    Coal tar is a by-product of the coal gasification process used between 1820 and 1950 to produce a gasified fuel. This material contains numerous monoaromatic and polynuclear aromatic hydrocarbons (PAH) some of which are considered to be carcinogenic. Environmentally disposed coal tar can migrate downward through the soil leaving a light fraction floating on the groundwater, referred to here as liquid coal tar. This research was carried out to determine whether liquid coal tar recovered during site clean-up operations could be cost-effectively biodegraded. Preliminary aqueous microcosm experiments demonstrated that the liquid tar was not toxic to site bacteria in concentrations up to 220,000 ppm. Liquid tar was treated in a 15 liter laboratory bioreactor operated in a batch mode with gas phase oxygen as the oxygen source. Thirty-nine major constituents were followed during treatment. In the first 63 days of operation 87% of these compounds were biodegraded or transformed. 2-, 3-, and 4-ring PAH were degraded 89%, 90%, and 70% respectively. Of the volatile compounds 89% were degraded and only 0.7% were trapped on carbon during reactor off-gassing

  12. Impact of sludge stabilization processes and sludge origin (urban or hospital) on the mobility of pharmaceutical compounds following sludge landspreading in laboratory soil-column experiments.

    Lachassagne, Delphine; Soubrand, Marilyne; Casellas, Magali; Gonzalez-Ospina, Adriana; Dagot, Christophe

    2015-11-01

    This study aimed to determine the effect of sludge stabilization treatments (liming and anaerobic digestion) on the mobility of different pharmaceutical compounds in soil amended by landspreading of treated sludge from different sources (urban and hospital). The sorption and desorption potential of the following pharmaceutical compounds: carbamazepine (CBZ), ciprofloxacin (CIP), sulfamethoxazole (SMX), salicylic acid (SAL), ibuprofen (IBU), paracetamol (PAR), diclofenac (DIC), ketoprofen (KTP), econazole (ECZ), atenolol (ATN), and their solid-liquid distribution during sludge treatment (from thickening to stabilization) were investigated in the course of batch testing. The different sludge samples were then landspread at laboratory scale and leached with an artificial rain simulating 1 year of precipitation adapted to the surface area of the soil column used. The quality of the resulting leachate was investigated. Results showed that ibuprofen had the highest desorption potential for limed and digested urban and hospital sludge. Ibuprofen, salicylic acid, diclofenac, and paracetamol were the only compounds found in amended soil leachates. Moreover, the leaching potential of these compounds and therefore the risk of groundwater contamination depend mainly on the origin of the sludge because ibuprofen and diclofenac were present in the leachates of soils amended with urban sludge, whereas paracetamol and salicylic acid were found only in the leachates of soils amended with hospital sludge. Although carbamazepine, ciprofloxacin, sulfamethoxazole, ketoprofen, econazole, and atenolol were detected in some sludge, they were not present in any leachate. This reflects either an accumulation and/or (bio)degradation of these compounds (CBZ, CIP, SMX, KTP, ECZ, and ATN ), thus resulting in very low mobility in soil. Ecotoxicological risk assessment, evaluated by calculating the risk quotients for each studied pharmaceutical compound, revealed no high risk due to the

  13. Processing method and device of radioactive sludge waste

    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. Sludge recovery apparatus

    An improved design of a sludge recovery apparatus used in the fabrication of nuclear fuel is described. This apparatus provides for automatic separation of sludge from the grinder coolant, drying of the sludge into a flowable powder and transfer of the dry powder to a salvage container. It can be constructed to comply with criticality-safe-geometry requirements and to obviate need for operating personnel in its immediate vicinity. (UK)

  15. Two step esterification-transesterification process of wet greasy sewage sludge for biodiesel production.

    Urrutia, C; Sangaletti-Gerhard, N; Cea, M; Suazo, A; Aliberti, A; Navia, R

    2016-01-01

    Sewage sludge generated in municipal wastewater treatment plants was used as a feedstock for biodiesel production via esterification/transesterification in a two-step process. In the first esterification step, greasy and secondary sludge were tested using acid and enzymatic catalysts. The results indicate that both catalysts performed the esterification of free fatty acids (FFA) simultaneously with the transesterification of triacylglycerols (TAG). Acid catalyst demonstrated better performance in FFA esterification compared to TAG transesterification, while enzymatic catalyst showed the ability to first hydrolyze TAG in FFA, which were esterified to methyl esters. In addition, FAME concentration using greasy sludge were higher (63.9% and 58.7%), compared with those of secondary sludge (11% and 16%), using acid and enzymatic catalysts, respectively. Therefore, only greasy sludge was used in the second step of alkaline transesterification. The alkaline transesterification of the previously esterified greasy sludge reached a maximum FAME concentration of 65.4% when using acid catalyst. PMID:26497113

  16. Energy and resource utilization of deinking sludge pyrolysis

    The thermochemical conversion technique was applied in deinking sludge from the pulp and papermaking industrial to indagate the utilization of sludge biomass to energy, and the pyrolysis characteristics and pyrolytic products of deinking sludge were studied with thermogravimetric analysis (TGA) and pyrolysis coupled with gas chromatograph–mass spectrometer (Py-GC/MS). The static tubular furnace as an applied industrial research was used to study deinking sludge pyrolysis. The solid, gas and liquid of products was characterized by electron probe microanalysis (EPMA), gas chromatograph (GC) and gas chromatograph–mass (GC/MS), respectively. The results revealed that the weight-loss process of deinking sludge was a non-isothermal reaction and composed of four stages, i.e. dewater stage, volatile releasing stage, carbon burnout stage and some calcium carbonate decomposition. Pyrolytic products from deinking sludge in the static tubular furnace were comprised of the gaseous (29.78%), condensed liquid (bio-oil, 24.41%) and solid residues (45.81%). The volatiles from deinking sludge pyrolyzing were almost aromatic hydrocarbons, i.e. styrene, toluene and benzene and few acids and the solid was calcium carbonate (CaCO3) that can be reused as paper filler. Deinking sludge was converted into high-grade fuel and chemicals by means of thermochemical conversion techniques, hence, pyrolysis of paper deinking sludge had a promising development on the comprehensive utilization.

  17. Effect of proteins, polysaccharides, and particle sizes on sludge dewaterability

    SHAO Liming; HE Peipei; YU Guanghui; HE Pinjing

    2009-01-01

    Four batch experiments of hydrolysis and acidification were carried out to investigate the distributions of proteins (PN) and polysaccharides (PS) in the sludge, the PN/PS ratio, the particle sizes, and their relationship with sludge dewaterability (as determined by capillary suction time, CST). The sludge flocs were stratified through centrifugation- and ultrasound-based method into four layers: (1) slime, (2) loosely bound extracellular polymeric substances (LB-EPS), (3) tightly bound EPS (TB-EPS), and (4) pellet. The results showed that PN was mainly partitioned in the pellet (80.7%) and TB-EPS (9.6%) layers, while PS distributed evenly in the four layers. During hydrolysis and acidification, PN was transferred from the pellet and TB-EPS layers to the slime layer, but PS had no significant transfer trends. The mean particle sizes of the sludge flocs decreased with hydrolysis and acidification. The pH had a more significant influence on the dewaterability of sludge flocs than temperature. Sludge dewaterability during hydrolysis and acidification processes greatly deteriorated from 9.7 s at raw sludge to 340--450 s under alkaline conditions. However, it was just slightly increased under acidic conditions. Further investigation suggested that CST was affected by soluble PN, soluble PN/PS, and particle sizes of sludge flocs, but was affected slightly by total PN, PS, or PN/PS in the whole sludge flocs and other layers (except slime).

  18. Separation of organic ion exchange resins from sludge - engineering study

    This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation

  19. Separation of organic ion exchange resins from sludge -- engineering study

    Duncan, J.B.

    1998-08-25

    This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation.

  20. Biogeochemical gradients above a coal tar DNAPL.

    Scherr, Kerstin E; Backes, Diana; Scarlett, Alan G; Lantschbauer, Wolfgang; Nahold, Manfred

    2016-09-01

    Naturally occurring distribution and attenuation processes can keep hydrocarbon emissions from dense non aqueous phase liquids (DNAPL) into the adjacent groundwater at a minimum. In a historically coal tar DNAPL-impacted site, the de facto absence of a plume sparked investigations regarding the character of natural attenuation and DNAPL resolubilization processes at the site. Steep vertical gradients of polycyclic aromatic hydrocarbons, microbial community composition, secondary water quality and redox-parameters were found to occur between the DNAPL-proximal and shallow waters. While methanogenic and mixed-electron acceptor conditions prevailed close to the DNAPL, aerobic conditions and very low dissolved contaminant concentrations were identified in three meters vertical distance from the phase. Comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS) proved to be an efficient tool to characterize the behavior of the present complex contaminant mixture. Medium to low bioavailability of ferric iron and manganese oxides of aquifer samples was detected via incubation with Shewanella alga and evidence for iron and manganese reduction was collected. In contrast, 16S rDNA phylogenetic analysis revealed the absence of common iron reducing bacteria. Aerobic hydrocarbon degraders were abundant in shallow horizons, while nitrate reducers were dominating in deeper aquifer regions, in addition to a low relative abundance of methanogenic archaea. Partial Least Squares - Canonical Correspondence Analysis (PLS-CCA) suggested that nitrate and oxygen concentrations had the greatest impact on aquifer community structure in on- and offsite wells, which had a similarly high biodiversity (H' and Chao1). Overall, slow hydrocarbon dissolution from the DNAPL appears to dominate natural attenuation processes. This site may serve as a model for developing legal and technical strategies for the treatment of DNAPL-impacted sites where contaminant plumes are absent or

  1. K basins sludge removal sludge pretreatment system

    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

  2. Hot balls dry sludge

    Hartmann, L.

    2004-01-01

    Each year some 25 million m3 of mineral sludge are dredged from rivers, canals and harbours in the Netherlands alone, twenty percent of which is polluted. The unpolluted sludge is usually dumped at sea. The remaining five million m3 may only be dumped in a few selected landfill locations, at conside

  3. Anaerobic sludge granulation

    Hulshoff Pol, L.W.; Castro Lopes, de S.I.; Lettinga, G.; Lens, P.N.L.

    2004-01-01

    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades
    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades. The initial stage

  4. Comparative Research on EPS Extraction from Mechanical Dewatered Sludge with Different Methods

    Weiyun Wang

    2015-09-01

    Full Text Available In order to find a suitable extracellular polymer substance (EPS extraction method for mechanical dewatered sludge, four different methods including EDTA extraction, alkali extraction, acid extraction, ultrasonic extraction method have been used in extracting EPS from belt filter dewatered sludge. The contents of polysaccharide and proteins extracted from the dewatered sludge by different extraction methods are also analyzed. The results indicated that EDTA method and alkali extraction method are more suitable for dewatered sludge with more EPS content and less cell damage, while sulfuric acid extraction and ultrasonic extraction were poorer with obvious cell lysis shown by higher DNA content in extracted EPS. Contents of proteins and polysaccharide in EPS extracted from mechanical dewatered sludge, is at the contents between that in EPS extracted from activated sludge and anaerobic digestion sludge.

  5. Consideration of Sludge Formation in HFC-134a / Polyol Ester oil Refrigeration System

    Yamamoto, Tsutomu; Yamamoto, Tethuya; Simizu, Yasuhiko; Nakayama, Yoshinori; Takizawa, Kikuo

    A refrigeration test employing HFC-134a and polyol ester oil was carried out in order to make clear the causes of the sludge formation in the capillary tube. Compressors used were two types: a hermetic reciprocating compressor and a rotary compressor. Installed dryer contained desiccant of the compound zeolite type. The results showed that the amount of capillary sludge increased as the compressor temperature rose. The capillary sludge was determined to consist of desiccant and metal dust for the reciprocating compressor, and of tar-like substance for the rotary compressor. Thermal stability test which was used to check the degree of deterioration of the ester oil, suggested that the presence of desiccant and high compressor temperature might produce tar-like substance by the break down and polymerization of the ester oil. In addition, it was confirmed that factors affecting the sludge formation were the dirtiness of the refrigeration circuit for the reciprocating compressor, and the presence of desiccant, for the rotary compressor.

  6. 硫酸浸出电镀污泥中Zn、Cr条件及其动力学研究%Study on the Conditions and Kinetics on Sulfuric Acid Leaching Zinc and Chromium from Electro-plating Sludge

    姚倩; 张宇峰; 葛苏苏; 汤传栋; 张慧

    2015-01-01

    采用硫酸作为酸浸出剂,考察了浸出时间、酸浓度和浸出温度对电镀污泥中重金属Zn、Cr浸出效果的影响,并运用Avrami方程拟合Zn、Cr的浸出动力学。结果表明:硫酸浸出Zn、Cr的最适浸出时间、酸浓度、温度均为4h、3mol/L、20℃。Zn、Cr的浸出过程均可用Avrami方程进行很好的拟合,其浸出反应的表观活化能分别为3.58和3.06kJ/mol,即两者的浸出过程均是扩散控制的,为工业规模的硫酸浸出电镀污泥中Zn、Cr提供理论参考。%This article,using sulphuric acid as acid leaching agent,investigates the effects of leaching time, acid concentration and leaching temperature on the leaching effect of zinc and chromium which are heavy metals from electroplating sludge,and uses Avrami equation to fit the leaching kinetics of zinc and chromi⁃um. The results showed that:both the optimum leaching time,acid concentration and temperature of sulph⁃uric acid leaching zinc and chromium are 4h,3mol/L and 20°C. Avrami equation could be used to fit both the leaching process of zinc and chromium very well,and the apparent activation energy of the leaching re⁃action are 3.58 and 3.06kJ/mol respectively,that is,both the leaching process are controlled by diffusion, which provides the theory reference for the sulfuric acid leaching zinc and chromium from electroplating sludge on an industrial scale.

  7. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

    Bryer, P.J.; Scoggins, M.; McClintock, N.L. [Lamar University, Beaumont, TX (United States). Dept. of Biology

    2010-05-15

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments.

  8. 生物质焦油催化裂解过程中酸性催化剂积碳失活与烧焦再生特性%Deactivation and Burning Regeneration of Coked Acid Catalysts in Catalytic Cracking Process of Biomass Tar

    李永玲; 吴占松

    2014-01-01

    为了研究酸性催化剂积碳失活以及再生特性,在固定床反应器上,以高铝砖作为催化剂,进行了生物质焦油催化裂解实验。实验结果表明,由于催化剂表面积碳,造成催化剂活性随着作用时间增加而下降。但当催化剂工作一定时间后,催化剂表面的积碳速率开始变得平缓,单层积碳向多层积碳转变。当积碳速率与反应中焦炭脱除速率达到平衡时,催化剂表面积碳量将趋于稳定。实验中采用烧焦法有效地恢复了催化剂的活性,但是焦炭燃烧会破坏催化剂表面的酸性结构,减少表面活化位,使得再生后的催化剂并不能完全达到新鲜催化剂所具有的催化能力。而且烧焦再生过程中会发生烧结,结晶等现象,改变催化剂的孔隙率、孔径分布、比表面积等物理特性。%In order to study the activity regeneration of deactivating acid catalysts with carbon deposition, the catalytic cracking experiments on biomass tar were carried out in a fixed bed reactor with high-alumina brick as acid catalyst. The results show that the catalyst activity declines with the increase of reaction time, due to the carbon depositing on catalyst surface. The carbon depositing rate on catalyst surface becomes smooth after a period of work time, and the mode of coke deposition becomes multi-layer form monolayer. The quantities of the carbon depositing on the catalyst surface will be stable, when the coking rate is equal to the rate of coke consumption. The regeneration method of coke burning can effectively recover the activity of catalyst. But the activity of regenerated catalyst cannot be the same as that of fresh catalyst, because the acidic structure and active center on catalyst surface are destroyed in coke combustion process. In addition, the sintering or crystallization phenomenon will occur in catalysts regeneration process with coke burning, which may change the physical

  9. K Basin sludge treatment process description

    Westra, A.G.

    1998-08-28

    The K East (KE) and K West (KW) fuel storage basins at the 100 K Area of the Hanford Site contain sludge on the floor, in pits, and inside fuel storage canisters. The major sources of the sludge are corrosion of the fuel elements and steel structures in the basin, sand intrusion from outside the buildings, and degradation of the structural concrete that forms the basins. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be treated so that it meets Tank Waste Remediation System (TWRS) acceptance criteria and can be sent to one of the double-shell waste tanks. The US Department of Energy, Richland Operations Office accepted a recommendation by Fluor Daniel Hanford, Inc., to chemically treat the sludge. Sludge treatment will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and reacting the solution with caustic to co-precipitate the uranium and plutonium. A truck will transport the resulting slurry to an underground storage tank (most likely tank 241-AW-105). The undissolved solids will be treated to reduce the transuranic (TRU) and content, stabilized in grout, and transferred to the Environmental Restoration Disposal Facility (ERDF) for disposal. This document describes a process for dissolving the sludge to produce waste streams that meet the TWRS acceptance criteria for disposal to an underground waste tank and the ERDF acceptance criteria for disposal of solid waste. The process described is based on a series of engineering studies and laboratory tests outlined in the testing strategy document (Flament 1998).

  10. K Basin sludge treatment process description

    The K East (KE) and K West (KW) fuel storage basins at the 100 K Area of the Hanford Site contain sludge on the floor, in pits, and inside fuel storage canisters. The major sources of the sludge are corrosion of the fuel elements and steel structures in the basin, sand intrusion from outside the buildings, and degradation of the structural concrete that forms the basins. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be treated so that it meets Tank Waste Remediation System (TWRS) acceptance criteria and can be sent to one of the double-shell waste tanks. The US Department of Energy, Richland Operations Office accepted a recommendation by Fluor Daniel Hanford, Inc., to chemically treat the sludge. Sludge treatment will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and reacting the solution with caustic to co-precipitate the uranium and plutonium. A truck will transport the resulting slurry to an underground storage tank (most likely tank 241-AW-105). The undissolved solids will be treated to reduce the transuranic (TRU) and content, stabilized in grout, and transferred to the Environmental Restoration Disposal Facility (ERDF) for disposal. This document describes a process for dissolving the sludge to produce waste streams that meet the TWRS acceptance criteria for disposal to an underground waste tank and the ERDF acceptance criteria for disposal of solid waste. The process described is based on a series of engineering studies and laboratory tests outlined in the testing strategy document (Flament 1998)

  11. Anaerobic treatment of thermal sludge conditioning liquor with granular sludge

    Thermal sludge conditioning liquor was successfully treated by a pilot-scale upflow anaerobic hybrid system with an effective volume of 10.4 m3. The reactor was similar to the HYAN reactor in Lakeview but without a recirculation system. A gas-solid separator was installed above a filter packed with polypropylene pall rings. The organic loading rate was increased stepwise to 30 kg chemical oxygen demand (COD)/m3·d. The hydraulic retention time was only 6 hours at the target loading rate. More than 70% of soluble COD in the influent was removed, even at an organic loading as high as 30 kg COD/m3·d. Soluble 5-day biochemical oxygen demand (BOD5) removal efficiency at the loading rate exceeded 95%. Volatile fatty acids concentration in the effluent was consistently less than 60 mg/L after the day when stable treatment had been obtained. The methane production fluctuated between 0.3 and 0.4 L/g COD removed. The inside of the reactor consisted of two zones, a sludge blanket zone with less than 1% solids concentration and a sludge bed zone with 4-7% solids concentration. Although the reactor was seeded with an anaerobically digested sludge, granular sludge was produced in the reactor. The ratio of granules to the solids remaining in the reactor increased to approximately 70% at the end of the experiments. Most of the granules had diameters of less than 1 mm and their settling velocity was 0.6 cm/s or more. The granules were composed of bacteria like Methanothrix according to SEM observations. The methane production rate was between 0.8 and 1.1 kg methane as COD/kg SS·d in an acetate solution. According to substrates distribution in the reactor and tracer tests, the bed zone in the reactor worked similarly to a continuously stirred tank reactor (CSTR). Evaluation of soluble COD removal rates in the reactor indicated that the rate could be simulated by a Monod type reaction. 10 refs., 12 figs., 8 tabs

  12. Sorption of perfluoroalkyl substances in sewage sludge.

    Milinovic, Jelena; Lacorte, Silvia; Rigol, Anna; Vidal, Miquel

    2016-05-01

    The sorption behaviour of three perfluoroalkyl substances (PFASs) (perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanesulfonic acid (PFBS)) was studied in sewage sludge samples. Sorption isotherms were obtained by varying initial concentrations of PFOS, PFOA and PFBS. The maximum values of the sorption solid-liquid distribution coefficients (Kd,max) varied by almost two orders of magnitude among the target PFASs: 140-281 mL g(-1) for PFOS, 30-54 mL g(-1) for PFOA and 9-18 mL g(-1) for PFBS. Freundlich and linear fittings were appropriate for describing the sorption behaviour of PFASs in the sludge samples, and the derived KF and Kd,linear parameters correlated well. The hydrophobicity of the PFASs was the key parameter that influenced their sorption in sewage sludge. Sorption parameters and log(KOW) were correlated, and for PFOS (the most hydrophobic compound), pH and Ca + Mg status of the sludge controlled the variation in the sorption parameter values. Sorption reversibility was also tested from desorption isotherms, which were also linear. Desorption parameters were systematically higher than the corresponding sorption parameters (up to sixfold higher), thus indicating a significant degree of irreversible sorption, which decreased in the sequence PFOS > PFOA > PFBS. PMID:26780052

  13. Phosphorus Recovery from Ashes of Sewage Sludge

    Cornel, Peter; Schaum, Peter

    2003-07-01

    About 90% of the incoming phosphorus load of waste water is eliminated by waste water treatment and transferred into the sewage sludge. Considerable amounts of sewage sludge can not be used agriculturally but are incinerated. Thus the ash from mono sludge incineration plants contains significant amounts of phosphorus (up to 25% P{sub 2}O{sub 5}) and could be used as raw material in fertilizer industry. The ash is hygienically harmless and free of organic substances. The ratio of phosphorus to heavy metals is basically the same as in the sewage sludge. The first step in separating phosphorus from heavy metals is to dissolve phosphorus by extraction. The most promising way seems to be the release of phosphorus with acids or bases. With 1 m sulphuric acid it is possible to release phosphorus completely. By use of acid most of the heavy metals dissolve, too. With caustic soda as solvent, only 30-40% of the phosphorus can be dissolved but the eluate is almost free of heavy metals. The amount of phosphorus which can be released with caustic soda, depends on the applied precipitant (Al or Fe salts) for phosphorus elimination at the waste water treatment. (author)

  14. Sludge Batch 2 (Marcobath 3) Flowsheet Studies with Simulants

    Sludge-only process simulations of the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) cycle were conducted for the two most likely scenarios for Sludge Batch 2 (Macrobatch 3). The two scenarios are a roughly 50:50 blend of Tank 8 and Tank 40 washed sludge and Tank 40 washed sludge by itself. The testing used new simulants of Tank 8 and Tank 40 washed sludge prepared at the University of South Carolina. The washing endpoint was about 0.5 moles sodium per liter supernate. This report summarizes both the simulant preparation and process simulation activities. The rheology work requested in the Task Plan will be documented in a separate report. Two scoping SRAT simulations were conducted for Tank 40 sludge. This was followed by a complete SRAT and SME simulation using Sludge Batch 1B acid stoichiometry (137.5 percent). Four scoping SRAT simulations were conducted for the Tank 8/40 blend. Three complete SRAT and SME simulations using blended sludge were then performed. One was at the recommended acid stoichiometry of 125 percent. The second used identical acid stoichiometry with HM levels of noble metals. The final run was at worst case noble metals and assumed complete transfer of the Formic Acid Feed Tank. Testing was completed without any major incidents. Hydrogen flow rates in excess of the design bases (0.65 lbs./hr for the SRAT and 0.23 lbs./hr for the SME) are marked in bold. Full details on the noble metals concentrations can be found in the body of the report

  15. Sludge Batch 2 (Marcobath 3) Flowsheet Studies with Simulants

    Koopman, D.C.

    2001-03-02

    Sludge-only process simulations of the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) cycle were conducted for the two most likely scenarios for Sludge Batch 2 (Macrobatch 3). The two scenarios are a roughly 50:50 blend of Tank 8 and Tank 40 washed sludge and Tank 40 washed sludge by itself. The testing used new simulants of Tank 8 and Tank 40 washed sludge prepared at the University of South Carolina. The washing endpoint was about 0.5 moles sodium per liter supernate. This report summarizes both the simulant preparation and process simulation activities. The rheology work requested in the Task Plan will be documented in a separate report. Two scoping SRAT simulations were conducted for Tank 40 sludge. This was followed by a complete SRAT and SME simulation using Sludge Batch 1B acid stoichiometry (137.5 percent). Four scoping SRAT simulations were conducted for the Tank 8/40 blend. Three complete SRAT and SME simulations using blended sludge were then performed. One was at the recommended acid stoichiometry of 125 percent. The second used identical acid stoichiometry with HM levels of noble metals. The final run was at worst case noble metals and assumed complete transfer of the Formic Acid Feed Tank. Testing was completed without any major incidents. Hydrogen flow rates in excess of the design bases (0.65 lbs./hr for the SRAT and 0.23 lbs./hr for the SME) are marked in bold. Full details on the noble metals concentrations can be found in the body of the report.

  16. Immobilization of activated sludge using improved polyvinyl alcohol (PVA) gel

    2007-01-01

    The microbial immobilization method using polyvinyl alcohol (PVA) gel as an immobilizing material was improved and used for entrapment of activated sludge. The OUR (oxygen uptake rate) was used to characterize the biological activity of immobilized activated sludge. Three kinds of PVA-immobilized particles of activated sludge, that is, PVA-boric acid beads, PVA-sodium nitrate beads and PVA-orthophosphate beads was prepared, and their biological activity was compared by measuring the OUR value. The bioactivity of both autotrophic and heterotrophic microorganisms of activated sludge was determined using different synthetic wastewater media (containing 250 mg/L COD and 25 mg/L NH4+-N). The experimental results showed that the bioactivity and stability of the three kinds of immobilized activated sludge was greatly improved after activation. With respect of the bioactivity and the mechanical stability, the PVA-orthophosphate method may be a promising and economical technique for microbial immobilization.

  17. Groundwater and contaminant transport modelling at the Sydney Tar Ponds

    King, M. [Groundwater Insight Inc., Halifax, NS (Canada); Check, G. [Jacques Whitford Environment Ltd., Halifax, NS (Canada); Carey, G. [Environmental Inst. for Continuing Education, Waterloo, ON (Canada); Abbey, D. [Waterloo Hydrogeologic, Waterloo, ON (Canada); Baechler, F. [ADI Ltd., Sydney, NS (Canada)

    2003-07-01

    The Muggah Creek Watershed, a tidal estuary located in Sydney, Nova Scotia, is known locally as the Tar Ponds. Over the past century, the Tar Ponds have accumulated contaminants in the contributing watershed from the iron, steel and coke manufacturing. There are sediments contaminated with polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). A groundwater modelling program was developed to estimate current contaminant fluxes to the estuary and site streams, through groundwater. Attempts were made to incorporate a complex stratigraphic profile, where groundwater flow and contaminant transport is strongly controlled by shallow fractured bedrock, into the conceptual model developed for the site. This conceptual model for groundwater flow and contaminant transport at the Sydney Tar Ponds site was presented. The complex flow patterns between bedrock and overburden, and between the bedrock units and surface water bodies were illustrated with model simulations. It was found that groundwater flow was dominated by discharge to the streams and the estuary. 6 refs., 2 tabs., 11 figs.

  18. Recovery of phosphorus from sewerage treatment sludge

    Manuilova, Anastasia

    1999-07-01

    This thesis is a review of the current state of technologies for the removal of phosphorus from wastewater and sludge, and the recovery and re-use of phosphorus. It explains the need for phosphorus removal and describes the current removal processes. Focus is given to phosphorus crystallisation processes and to the processes which treat sewage treatment sludges into potential sources of phosphorus. An interesting possibility to recover phosphorus from sewage sludge by use of Psenner fractionation is also discussed. By this method, the following phosphate fractions of technological significance may be distinguished: (1) redox sensitive phosphates, mainly bound to Fe(OH){sub 3}; (2) phosphate adsorbed to surfaces (Al{sub 2}O{sub 3}), exchangeable against OH{sup -}, and alkali-soluble phosphate; (3) phosphate bound to CaCO{sub 3}, MgCO{sub 3} and in apatite; and (4) organically bound phosphate. The basic removal mechanisms, process schemes and treatment results are described. Two experiments with three different types of sludges from Henriksdal wastewater treatment plant in Stockholm were performed in the laboratory. It was shown that the addition of sodium hydroxide or hydrochloric acid cause the significant release of phosphate (about 80%) for all types of sludges. If a whole Psenner fractionation was performed the phosphate release is approximately 100%.

  19. Remediation of sites with coal tar contamination. A case study

    The production and use of coal tar was tied to the industrial revolution and its dependence on coal for energy and as chemical feedstock for a large range of organic and inorganic products. Coal tar was produced, often as a byproduct, by coal gasification plants. The North American coal tar production in the mid 1950s was in the order of 25 billion litres. The production, handling, storage and use of coal tar and its derivatives generated a legacy of soil and groundwater contamination that today requires remediation at high costs. At one such site, coal tar was manufactured into a variety of roofing and tarbased products, as well as the production of creosote, oil stains, solvents and anhydrous ammonia. Over its 60 years of operation, a number of chemicals were leaked, dumped or released to the soil and groundwater on the site, of which the most significant was a brown dense non-aqueous phase liquid (DNAPL) with an oil-like viscosity. This DNAPL migrated from the fill, through a pre-development floodplain silt layer and into an underlying sand aquifer. Portions of the DNAPL moved along preferential pathways associated with the coarser material in the aquifer and reached the nearby river sediments, resulting in elevated concentrations of polyaromatic hydrocarbons (PAH). Site remediation was conducted mitigate risks posed by the coal tar. Remediation has included: in-place management of deep soil contamination, removal of shallow soil with high PAH concentrations (i.e., 10 times the provincial concentration standards for commercial land use), control of dissolved contamination in groundwater, and recovery of free- phase creosote. The remediation also provided long-term protection of the adjacent aquatic habitat through a combination of groundwater and DNAPL control and recovery, removal of near-shore contaminated sediments, and containment and natural attenuation of far-shore contaminated sediments through the use of a layer of crushed rock placed as a protective cap

  20. Proposed water treatment approach for commercial tar sand wastewaters

    Kocornik, D.

    1986-09-01

    Waters produced during the steamflood extraction of bitumen from tar sand require treatment before they can be recycled as feedwater for steam generation. The characterization of two waters from commercial-scale tar sand operations indicates that the levels of hardness, oil and grease, silica, suspended solids, and iron must be reduced before these waters can be reused in the bitumen extraction process. The Western Research Institute proposes two treatment methods (electrocoagulation and ultrafiltration) that may, when used in conjunction with standard practices, improve the efficiency of the overall treatment process. 21 refs., 3 tabs.

  1. Luminescence monitoring of oil or tar contamination for industrial hygiene

    Synfuel plants produce potentially carcinogenic oils and tars. Exposure of workers to these tars and oils is difficult to avoid completely and occurs via direct contact with dirty surfaces or condensation of escaped fumes onto or within the body. Surface skin, measurements are made directly with a near-ultraviolet luminoscope employing a fiber optics lightguide and a stethoscopic cap pressed against the skin. This instrument is especially suitable for measuring ng to μg/cm2 amounts of residual contamination remaining on the surface of the skin after washing. To minimize the potential for carcinogenicity, the excitating ultraviolet light intensity is only 1/100th that of sunlight. (orig.)

  2. Dewatering of sludges

    A filter rig has been designed and built. Simulated magnox and alumino ferric hydroxide sludges have been successfully filtered on this equipment and both types of sludge produced a clear filtrate and a cake. The flow rates were low. The cake often partially remained adhered to the filter membrane instead of dropping clear during the filter cleaning cycle. This filtration technique can only be used on sludges which form a non-binding cake. Permeability of the membrane can be altered by stretching. Irradiation of the membrane showed that it should withstand 20 to 50 M.rads. (author)

  3. Design and synthesis of á,á-trehalose derivatives bearing guanidino groups as inhibitors for the Tat Protein-TAR RNA interaction of HIV-1

    Wang Min; Xu Zhidong; Tu Pengfei; Xiao Sulong; Yu Xiaolin; Yang Ming

    2004-01-01

    Replication of human immunodeficiency virus type 1 (HIV-1) requires specific interactions of Tat protein with the transactivation responsive region (TAR) RNA. Disruption of Tat-TAR RNA interaction could inhibit HIV-1 replication. Here four target compounds were designed and synthesized to bind to TAR RNA for blocking the interaction of Tat-TAR RNA. The core molecule 6,6′-diamino-6,6′ -dideoxy-á,á-trehalose was obtained from selective bromination of a,a-trehalose at C-6,6′, followed by acetylation, azide displacement, deacetylation and reduction.Coupling of the core molecule with the protected amino acid, then deprotection and guanidinylation generated 6,6′-bis(L-arginylamino)-6,6′-dideoxy-á,á-trehalose,6,6′-bisguanidino-6,6′-dideoxy-á ,á-trehalose, 6,6′-bis [((a)-guanidinobutyryl)amino]-6,6′-dideoxy-á,á-trehalose and 6,6′-bis(guanidinoacetylamino)-6,6′-dideoxy-á,á-trehalose, respectively.Their abilities to inhibit Tat-TAR RNA interaction were determined by a Tat-dependent HIV-1LTR-driven CAT assays.

  4. Investigation of sulfur-polycyclic aromatic hydrocarbon in coal derived tars of pyrolysis and hydropyrolysis

    Chen, H.; Li, B.; Zhang, B. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion

    1999-07-01

    A study was undertaken to characterize sulphur forms in coal derived tars from pyrolysis and hydropyrolysis of bituminous coal and lignite. The pyrolysis tars were analyzed for content of polycyclic aromatic sulfur hydrocarbons (PASH). 5 refs., 3 figs., 3 tabs.

  5. In situ recovery of oil from Utah tar sand: a summary of tar sand research at the Laramie Energy Technology Center

    Marchant, L.C.; Westhoff, J.D.

    1985-10-01

    This report describes work done by the United States Department of Energy's Laramie Energy Technology Center from 1971 through 1982 to develop technology for future recovery of oil from US tar sands. Work was concentrated on major US tar sand deposits that are found in Utah. Major objectives of the program were as follows: determine the feasibility of in situ recovery methods applied to tar sand deposits; and establish a system for classifying tar sand deposits relative to those characteristics that would affect the design and operation of various in situ recovery processes. Contents of this report include: (1) characterization of Utah tar sand; (2) laboratory extraction studies relative to Utah tar sand in situ methods; (3) geological site evaluation; (4) environmental assessments and water availability; (5) reverse combustion field experiment, TS-1C; (6) a reverse combustion followed by forward combustion field experiment, TS-2C; (7) tar sand permeability enhancement studies; (8) two-well steam injection experiment; (9) in situ steam-flood experiment, TS-1S; (10) design of a tar sand field experiment for air-stream co-injection, TS-4; (11) wastewater treatment and oil analyses; (12) economic evaluation of an in situ tar sand recovery process; and (13) appendix I (extraction studies involving Utah tar sands, surface methods). 70 figs., 68 tabs.

  6. Organic acids in the rhizosphere and phytoavailability of sewage sludge-borne trace elements Ácidos orgânicos na rizosfera e fitodisponibilidade de elementos-traço originários de lodo de esgoto

    Adriana Marlene Moreno Pires

    2007-07-01

    Full Text Available The aim of this work was to quantify low molecular weight organic acids in the rhizosphere of plants grown in a sewage sludge-treated media, and to assess the correlation between the release of the acids and the concentrations of trace-elements in the shoots of the plants. The species utilized in the experiment were cultivated in sand and sewage sludge-treated sand. The acetic, citric, lactic, and oxalic acids, were identified and quantified by high performance liquid chromatography in samples collected from a hydroponics system. Averages obtained from each treatment, concentration of trace elements in shoots and concentration of organic acids in the rhizosphere, were compared by Tukey test, at 5% of probability. Linear correlation analysis was applied to verify an association between the concentrations of organic acids and of trace elements. The average composition of organic acids for all plants was: 43.2, 31.1, 20.4 and 5.3% for acetic, citric, lactic, and oxalic acids, respectively. All organic acids evaluated, except for the citric acid, showed a close statistical agreement with the concentrations of Cd, Cu, Ni, and Zn found in the shoots. There is a positive relationship between organic acids present in the rhizosphere and trace element phytoavailability.O objetivo deste estudo foi quantificar ácidos orgânicos de baixo peso molecular presentes na rizosfera de plantas cultivadas na presença de lodo de esgoto e avaliar a correlação entre a liberação dos ácidos e a concentração de elementos-traço nas plantas. As espécies utilizadas no experimento foram cultivadas em areia e areia com lodo de esgoto. Os ácidos acético, cítrico, lático e oxálico foram identificados e quantificados por cromatografia líquida de alta eficiência em amostras coletadas de um sistema hidropônico. As médias obtidas em cada tratamento, para concentração de elementos-traço na parte aérea e para concentração de ácidos orgânicos rizosf

  7. Mineralogy and leachability of gasified sewage sludge solid residues

    Highlights: → Study of the solid residue's characterization, solids resulting from sewage sludge gasification. → Multi-technique approach is used to study the evolution of the mineralogy including innovative methods. → Sewage sludge mineralogy undergoes significant transformations during thermal treatment, influenced mainly by temperature and heating atmosphere. → Heavy metals are differently stabilized and located. → Steam gasification is an attractive route for sewage sludge disposal in view of the mobility of heavy metals retained in the residues. - Abstract: Gasification of sewage sludge produces combustible gases as well as tar and a solid residue as by-products. This must be taken into account when determining the optimal thermal conditions for the gasification process. In this study, the influence of temperature, heating atmosphere and residence time on the characteristics of the gasified sewage sludge residues is investigated. ICP-AES analyses reveal that the major chemical elements in the char residues are phosphorus, calcium, iron and silicon. Heavy metals such as copper, zinc, chromium, nickel and lead are also present at relatively high levels - from 50 to more than 1000 mg/kg of dry matter. The major mineral phases' identification - before and after heating - as well as their morphology and approximate chemistry (XRD and SEM-EDX) demonstrate that a number of transformations take place during gasification. These are influenced by the reactor's temperature and the oxidative degree of its internal atmosphere. The copper-, zinc- and chromium-bearing phases are studied using chemometric tools, showing that the distribution of those metals among the mineral phases is considerably different. Finally, batch-leaching tests reveal that metals retained in the residue are significantly stabilized after thermal treatment to a higher or lower extent, depending on the thermal conditions applied.

  8. Sewage sludges disinfection

    There is a hygienic risk in using biological sewage sludges for agriculture. Systematic analyses carried out on sludge samples obtained from purification plants in the Eastern and Southern part of France, show the almost uniform presence of pathogenic microorganisms. Some of them survive more than nine months after application to the soil. Conventional processes for disinfection, liming and heat, make the sludge unsuitable for agricultural use. On the other hand, irradiation involves no modification of structure and composition of sludges. Radiation doses required for disinfection vary according to the type of microorganism. Some of them are eliminated at rather low doses (200 krad), but mycobacteria, viruses and eggs of worms resist to more important doses. The security dose is estimated to be approx. 1000 krad

  9. pH dependency of hydrogen fermentation from alkali-pretreated sludge

    2006-01-01

    Batch tests were carried out to study the possibility of hydrogen production from alkali-pre- treated sludge without seed and the pH dependency of hydrogen fermentation from alkali-pretreated sludge. Experimental results showed that the sewage sludge with alkali-pretreatment could be successfully applied to biologically producing hydrogen without seed and extra-feed. The results also showed that the initial pH value of sewage sludge was an important factor throughout the hydrogen fermentation of alkali-pretreated sludge. The maximum hydrogen yield was obtained at initial pH value of 11.0 (14.4 mL·g VS-1). The hydrogen yield of alkali-pretreated sludge at alkaline initial pH value was much higher than that of acidic or neutral initial pH value. The optimal pH value of hydrogen production from alkali- pretreated sludge was approximately 9.5. The consumption of hydrogen could be inhibited when the pH value of sludge was above 8.5. The change of hydrogen yield at various initial pH values was similar to that of sludge SCOD. The change of sludge pH value was slow and acetate was the major component of volatile fatty acids produced in the process of hydrogen production. The yield and the constitution of volatile fatty acids were sensitive to the initial pH value.

  10. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    2010-04-01

    ... coal tar hair dye containing any ingredient listed in paragraph (b) of this section shall bear, in... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Coal tar hair dyes posing a risk of cancer. 740.18... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.18 Coal tar hair...

  11. Experimental comparison of biomass chars with other catalysts for tar reduction

    Abu El-Rub, Z.; Bramer, E.A.; Brem, G.

    2008-01-01

    In this paper the potential of using biomass char as a catalyst for tar reduction is discussed. Biomass char is compared with other known catalysts used for tar conversion. Model tar compounds, phenol and naphthalene, were used to test char and other catalysts. Tests were carried out in a fixed bed

  12. Sludge technology assessment

    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

  13. EPR spectroscopic analysis of TAR RNA-metal ion interactions

    Metal ion-induced changes in HIV-1 TAR RNA internal dynamics were determined by the changes in EPR spectral width for TAR RNAs containing spin-labeled nucleotides (U23, U25, U38, and U40). This gave a dynamic signature for each of 10 metal ions studied, which fell into one of three distinct groups. While Li+ and K+ had little effect on TAR RNA internal dynamics, Na+ unexpectedly had a dynamic signature that was similar to Ca2+ and Sr2+, with a decrease in mobility at U23 and U38, little or no change at U25, and an increase in mobility at U40. Mg2+, Co2+, Ni2+, Zn2+, and Ba2+ had similar effects on U23, U38, and U40, but the mobility of U25 was markedly increased. Our results show that RNA dynamics change upon metal binding to the TAR RNA bulge, indicating that RNA structure adapts to accommodate metal ions of different size and coordination properties

  14. Supercritical-Fluid Extraction of Oil From Tar Sands

    Compton, L. E.

    1982-01-01

    New supercritical solvent mixtures have been laboratory-tested for extraction of oil from tar sands. Mixture is circulated through sand at high pressure and at a temperature above critical point, dissolving organic matter into the compressed gas. Extract is recovered from sand residues. Low-temperature super-critical solvents reduce energy consumption and waste-disposal problems.

  15. Wet scrubbing of biomass producer gas tars using vegetable oil

    Bhoi, Prakashbhai Ramabhai

    The overall aims of this research study were to generate novel design data and to develop an equilibrium stage-based thermodynamic model of a vegetable oil based wet scrubbing system for the removal of model tar compounds (benzene, toluene and ethylbenzene) found in biomass producer gas. The specific objectives were to design, fabricate and evaluate a vegetable oil based wet scrubbing system and to optimize the design and operating variables; i.e., packed bed height, vegetable oil type, solvent temperature, and solvent flow rate. The experimental wet packed bed scrubbing system includes a liquid distributor specifically designed to distribute a high viscous vegetable oil uniformly and a mixing section, which was designed to generate a desired concentration of tar compounds in a simulated air stream. A method and calibration protocol of gas chromatography/mass spectroscopy was developed to quantify tar compounds. Experimental data were analyzed statistically using analysis of variance (ANOVA) procedure. Statistical analysis showed that both soybean and canola oils are potential solvents, providing comparable removal efficiency of tar compounds. The experimental height equivalent to a theoretical plate (HETP) was determined as 0.11 m for vegetable oil based scrubbing system. Packed bed height and solvent temperature had highly significant effect (p0.05) effect on the removal of model tar compounds. The packing specific constants, Ch and CP,0, for the Billet and Schultes pressure drop correlation were determined as 2.52 and 2.93, respectively. The equilibrium stage based thermodynamic model predicted the removal efficiency of model tar compounds in the range of 1-6%, 1-4% and 1-2% of experimental data for benzene, toluene and ethylbenzene, respectively, for the solvent temperature of 30° C. The NRTL-PR property model and UNIFAC for estimating binary interaction parameters are recommended for modeling absorption of tar compounds in vegetable oils. Bench scale

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

    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)

  17. Sludge Stabilization Campaign blend plan

    This sludge stabilization blend plan documents the material to be processed and the order of processing for the FY95 Sludge Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing sludge. The source of the sludge is residual and glovebox floor sweepings from the production of material at the Plutonium Finishing Plant (PFP). The reactive sludge is currently being stored in various gloveboxes at PFP. There are two types of the plutonium bearing material that will be thermally stabilized in the muffle furnace: Plutonium Reclamation Facility (PRF) sludge and Remote Mechanical C (RMC) Line material

  18. Sludge Stabilization Campaign blend plan

    De Vries, M.L.

    1994-10-04

    This sludge stabilization blend plan documents the material to be processed and the order of processing for the FY95 Sludge Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing sludge. The source of the sludge is residual and glovebox floor sweepings from the production of material at the Plutonium Finishing Plant (PFP). The reactive sludge is currently being stored in various gloveboxes at PFP. There are two types of the plutonium bearing material that will be thermally stabilized in the muffle furnace: Plutonium Reclamation Facility (PRF) sludge and Remote Mechanical C (RMC) Line material.

  19. [Effect of coal tar on cignolin erythema--1 hour treatment of psoriasis with high-dose cignolin with and without tar].

    Schauder, S; Mahrle, G

    1985-06-01

    Coal tar applied simultaneously showed a suppressive effect on anthralin erythema. This effect was demonstrated by an epicutaneous test 24 hours (27 patients) and 1 hour (46 patients) after application of various concentrations of anthralin combined with tar 3%. In a clinical study on 9 patients, anthralin 3% alone or combined with tar 10% were administered in a right and left comparison on symmetrical chronic psoriatic lesions for 1 hour daily. Anthralin plus tar exhibited a stronger anti-psoriatic effect than anthralin alone did. Tar reduced the anthralin erythema in the perilesional skin. These findings favor the combination of coal tar and anthralin in the 1-hour treatment schedule of psoriasis. PMID:3160177

  20. SLUDGE BATCH 4 SIMULANT FLOWSHEET STUDIES: PHASE II RESULTS

    Stone, M; David Best, D

    2006-09-12

    The Defense Waste Processing Facility (DWPF) will transition from Sludge Batch 3 (SB3) processing to Sludge Batch 4 (SB4) processing in early fiscal year 2007. Tests were conducted using non-radioactive simulants of the expected SB4 composition to determine the impact of varying the acid stoichiometry during the Sludge Receipt and Adjustment Tank (SRAT) process. The work was conducted to meet the Technical Task Request (TTR) HLW/DWPF/TTR-2004-0031 and followed the guidelines of a Task Technical and Quality Assurance Plan (TT&QAP). The flowsheet studies are performed to evaluate the potential chemical processing issues, hydrogen generation rates, and process slurry rheological properties as a function of acid stoichiometry. Initial SB4 flowsheet studies were conducted to guide decisions during the sludge batch preparation process. These studies were conducted with the estimated SB4 composition at the time of the study. The composition has changed slightly since these studies were completed due to changes in the sludges blended to prepare SB4 and the estimated SB3 heel mass. The following TTR requirements were addressed in this testing: (1) Hydrogen and nitrous oxide generation rates as a function of acid stoichiometry; (2) Acid quantities and processing times required for mercury removal; (3) Acid quantities and processing times required for nitrite destruction; and (4) Impact of SB4 composition (in particular, oxalate, manganese, nickel, mercury, and aluminum) on DWPF processing (i.e. acid addition strategy, foaming, hydrogen generation, REDOX control, rheology, etc.).

  1. Analysis of the environmental control technology for tar sand development

    de Nevers, N.; Glenne, B.; Bryner, C.

    1979-06-01

    The environmental technology for control of air pollution, water pollution, and for the disposal, stabilization, and vegetation of the waste tar sand were thoroughly investigated. Although some difficulties may be encountered in any of these undertakings, it seems clear that the air and water pollution problems can be solved to meet any applicable standard. Currently there are two large-scale plants producing liquid fuels from tar sands in Alberta, Canada which use similar technology involving surface mining, hot water extraction, and surface disposal of waste sand. These projects all meet the Canadian environmental control regulations in force at the time they began. The largest US deposits of tar sands are much smaller than the Canadian; 95 percent are located in the state of Utah. Their economics do not appear as attractive as the Canadian deposits. The environmental control costs are not large enough to make an otherwise economic project uneconomic. The most serious environmental conflict likely to occur over the recovery of liquid fuels from the US deposits of tar sands is that caused by the proximity of the deposits to national parks, national monuments, and a national recreation area in Utah. These areas have very stringent air pollution requirements; and even if the air pollution control requirements can be met, there may still be adequate opposition to large-scale mining ventures in these areas to prevent their commercial exploitation. Another environmental constraint may be water rights availability.Essentially all of the water running in the Colorado river basin is now legally allocated. Barring new interpretations of the legality of water rights purchase, Utah tar sands developments should be able to obtain water by purchasing existing irrigation water rights.

  2. Designing the IShTAR antenna: Physics and engineering aspects

    Louche, F.; Jacquot, J.; Crombé, K.; Van Eester, D.; D'Inca, R.; Devaux, S.; Faudot, E.; Faugel, H.; Fünfgelder, H.; Heuraux, S.; Morgal, I.; Moritz, J.; Ochoukov, R.; Noterdaeme, J.-M.

    2015-12-01

    IShTAR (Ion cyclotron Sheath Test ARrangement) is a magnetised plasma test facility installed at the Max-Planck-Institut für Plasmaphysik in Garching, Germany. The main purpose of this device is the study of RF sheaths generated in front of ICRF (Ion Cyclotron Range of Frequency) antennas in magnetically confined plasmas. The plasma is generated by a helical RF antenna potentially able to reach a helicon mode. We present in this work recent modelling activities dedicated to IShTAR. On the one hand a parameterized magnetostatic model of the magnetic configuration was created with the finite element solver COMSOL Multiphysics [3]. The model considers two non-axial sets of coils and notably reproduces the magnetic field lines deviation at the center of the main vessel and the ripples observed during experiments. From this model we can infer that kA are required in the 2 main large coils of IShTAR for 1 kA in the 4 small coils to generate a "smooth" magnetic field along field lines. On the other hand an ICRF antenna has been designed for IShTAR. A tridimensional model of the IShTAR vessel was developed with the electromagnetic code MicroWave Studio (MWS [4]) for this purpose and a first antenna model made of a single strap inside a box was included. The strap is fed through the upper port located at the helicon source side. The antenna is fully immersed into the loading medium (plasma or homogeneous dielectric) and the curved strap front face is aligned with the magnetic surfaces to simplify the modelling. The initial design of this antenna has been studied with MWS in the presence of homogeneous dielectric. The presence of a back wall will be discussed.

  3. Avoiding tar formation in biocoke production from waste biomass

    This paper focuses in avoiding tar formation and in optimizing pyrolysis gas (maximizing H2 and CO) in the production of biocoke from waste lignocellulosic biomass. In order to obtain metallurgical grade biochar (biocoke) slow heating rate and high temperature are required. Under such conditions useless pyrolysis liquids, mainly composed of water together with some heavy-sticky tars, are obtained. In order to make biocoke a cost-effective process it is necessary to optimize pyrolysis vapors avoiding tar formation and maximizing the amount and quality of both coke and gases. With this objective, in this work different heating rates (3–20 °C min−1) and catalysts (zeolite, Ni/CeO2–Al2O3) have been tested in a two step pyrolysis process. Olive tree cuttings have been pyrolyzed in a 3.5 L batch reactor at 750 °C and the vapors generated have been thermally and catalytically treated at 900 °C in a second tubular reactor. About 25 wt.% biocoke useful as reducing agent in certain metallurgical processes, ≈57 wt.% gases with near 50 vol.% H2, and no tar production has been achieved when a heating rate of 3 °C min−1 and the homemade Ni/CeO2–Al2O3 catalyst were used. - Highlights: • Metallurgical grade biochar was obtained by olive waste pyrolysis. • Low heating rates avoid tar formation and increase gas and biochar yields. • Ni/CeO2–Al2O3 was better than HZSM5 zeolite for vapor upgrading in a second step. • Ni/CeO2–Al2O3 and 3 °C min−1 gave the maximum H2, gas and biochar yields

  4. Monitoring of tar contents in gases. Final report

    Petersen, Finn [ChimneyLab Europe ApS, Hadsten (Denmark); Houmann Jakobsen, H. [BioSynergi Proces ApS, Hoersholm (Denmark)

    2012-08-15

    The purpose of this project is to develop and test a relative cheap and simple online tar measuring method, which can monitor the tar content in product gas from thermal gasification. The measuring principle is absorption of tar from sample gas in Isopropanol (IPA), and measuring on this solution by UV-spectrophotometer. Continuous sampling of tar containing producer gas turned out to be a larger problem than earlier foreseen. The best solution was decided to be sampling with higher flows, and afterwards cleaning the IPA in activated carbon. The ambitions for continuous sampling had to be decreased to 1 week, where the IPA and the activated carbon is contaminated by tar and has to be replaced. However this requires larger amounts of IPA and activated carbon. For IPA the weekly consumption was 12-15 Litres and for activated carbon 10 Litres. The whole analyzer unit turned out to be more complex than first projected, mainly because of the increased amounts of IPA. The best mist filter, with respect to pressure drop, efficiency and retention time is a combination of glass wool and quarts wool. The unit has been tested on gas; 20 kW pellets burner for 116 hours. Harbooere updraft gasifier for 519 hours. Skive fluid bed gasifier for 879 hours. There have during the project period been several simple practical problems such as bubbles in the IPA, increasing pressure drop over the activated carbon bed, dropout of UV data acquisition program and increasing baseline. The principle showed from the beginning some good results, with the limitation of 1 week continuous operation, but at the 5. period in Skive the baseline was increasing all the time, and it was not possible to solve this problem. (LN)

  5. Isolation of indole from coal-tar fractions by liquid extraction

    Zaretskii, M.I.; Chartov, E.M.; Golub, V.B.; Taits, S.Z.

    1981-01-01

    Indole is a valuable intermediate in fine organic synthesis; it is used in the perfumery industry, in the production of plant growth stimulants, notably heteroauxin and in the production of amino acids such as triptophan and its derivatives. In recent years, indole derivatives have also found use in the manufacture of medicinal preparations. The main source of indole in the USSR at present is the coking industry. Coal tars from southern and eastern plants contain 0.22 and 0.50% indole respectively, while the wash-oil fractions contain 1.7 to 2.0 and 3.5 to 4.5%, respectively. Coal tar could yield over 6000 tons/yr. A method has been developed for concentrating and isolating indole from commercial coking-plant fractions by continuous liquid extraction. Conditioned extract fractions have been made under test-rig conditions and have yielded 99% pure indole by rectification in an enlarged laboratory unit. The experimental results form the basis of a proposed processing flowsheet.

  6. SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 5 QUALIFICATION

    Pareizs, J; Cj Bannochie, C; Damon Click, D; Dan Lambert, D; Michael Stone, M; Bradley Pickenheim, B; Amanda Billings, A; Ned Bibler, N

    2008-11-10

    Sludge Batch 5 (SB5) is predominantly a combination of H-modified (HM) sludge from Tank 11 that underwent aluminum dissolution in late 2007 to reduce the total mass of sludge solids and aluminum being fed to the Defense Waste Processing Facility (DWPF) and Purex sludge transferred from Tank 7. Following aluminum dissolution, the addition of Tank 7 sludge and excess Pu to Tank 51, Liquid Waste Operations (LWO) provided the Savannah River National Laboratory (SRNL) a 3-L sample of Tank 51 sludge for SB5 qualification. SB5 qualification included washing the sample per LWO plans/projections (including the addition of a Pu/Be stream from H Canyon), DWPF Chemical Process Cell (CPC) simulations, waste glass fabrication (vitrification), and waste glass chemical durability evaluation. This report documents: (1) The washing (addition of water to dilute the sludge supernatant) and concentration (decanting of supernatant) of the Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF CPC simulation using the washed Tank 51 sample. This includes a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid is added to the sludge to destroy nitrite and remove mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit is added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters for the CPC processing were based on work with a non radioactive simulant. (3) Vitrification of a portion of the SME product and Product Consistency Test (PCT) evaluation of the resulting glass. (4) Rheology measurements of the initial slurry samples and samples after each phase of CPC processing. This work is controlled by a Task Technical and Quality Assurance Plan (TTQAP) , and analyses are guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R

  7. Leaching techniques to remove metals and potentially hazardous nutrients from trout farm sludge.

    Jung, I S; Lovitt, R W

    2011-11-15

    A fish farm sludge high in P (2-6% w/w as dry matter), Fe (5-7%), C (40-50%) and N (0.8-4%) was subjected to a series of acid leaching treatments using HCl, organic acids, and biologically mediated acid production. Additions of biodegradable organic acid solubilized heavy metals better than HCl, while additions of 1.5% w/v glucose followed by 7 day incubation stabilized the sludge releasing 92% P, 100% Fe. The use of homo-lactic Lactobacillus plantarum starter cultures were more effective than hetero-lactic Lactobacillus buchneri, solubilizing 81.9% P, 92.2% Fe, 93.0% Zn and 96.4% Ca in the sludge. The anaerobic sludge-glucose fermentation using L. plantarum produced a leached sludge that has low heavy metal and nutrient content while affording the recovery of nutrients. The potential of these methods for practical application are briefly discussed. PMID:21940031

  8. Reducing capacities and redox potentials of humic substances extracted from sewage sludge.

    Yang, Zhen; Du, Mengchan; Jiang, Jie

    2016-02-01

    Humic substances (HS) are redox active organic materials that can be extracted from sewage sludge generated in wastewater treatment processes. Due to the poor understanding of reducing capacity, redox potentials and redox active functional groups of HS in sewage sludge, the potential contribution of sludge HS in transformation of wastewater contaminants is unclear. In the present study, the number of electrons donated or accepted by sewage sludge HS were quantified before and after reduction by iron compounds that possess different redox potentials and defined as the reducing capacity of the sewage sludge. In contrast to previous studies of soil and commercial humic acids (HA), reduced sludge HA showed a lower reducing capacity than that of native HA, which implies formation of semiquinone radicals since the semiquinone radical/hydroquinone pair has a much higher redox potential than the quinone/hydroquinone pair. It is novel that reducing capacities of sludge HA were determined in the redox potential range from -314 to 430 mV. The formation of semiquinone radicals formed during the reduction of quinone moieties in sludge HA is shown by three-dimensional excitation/emission matrix fluorescence spectroscopies information, increasing fluorescence intensities and blue-shifting of the excitation/emission peak of reduced sludge HA. Knowledge of sludge HS redox potentials and corresponding reducing capacities makes it possible to predict the transformation of redox active pollutants and facilitate manipulation and optimization of sludge loading wastewater treatment processes. PMID:26432531

  9. Effects of solids concentration, pH and carbon addition on the production rate and composition of volatile fatty acids in prefermenters using primary sewage sludge

    Zeng, Raymond Jianxiong; Yuan, Z.; Keller, J.

    2006-01-01

    Increasing evidence is emerging that the performance of enhanced biological phosphorus removal (EBPR) systems relies on not only the total amount but also the composition of volatile fatty acids (VFAs). Domestic wastewater often contains limited amounts of VFAs with acetic acid typically being the...

  10. Fractional Distribution of Lead and Cadmium in Sludge and Soil Amended with Sludge Compost

    E Yong; BIAN Wei; SHAN Dexin; ZHANG Di; FU Chunlei

    2006-01-01

    The modified three-step sequential extraction procedure proposed by the BCR was used to predict Pb and Cd fractional distribution in sewage sludge and tomato soil amended with sludge compost. There was no significant increasing of Pb and Cd contents in the soil with sludge application as compared with that in the reference soil. The Pb contents were much lower for the soil samples than for the National Soil Standards of Environmental Quality, but Cd contents in soil were much more than background mean Cd contents. Pb content in soil fractions was followed with residual Pb > reducible Pb > exchangeable and weak acid soluble Pb > oxidizable Pb. In all soil samples, the partitioning of Cd had the same extractability in the first two steps of the procedure and the residual fraction. Only a small fraction or almost zero extractability was observed at the oxidation step for Pb and Cd.

  11. Thickening methods in sludge processing

    Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Golomeov, Blagoj

    2011-01-01

    The treatment of wastewater occur a large amount of sludge that contains high percentage of water and substances that provide a poor quality of wastewater (suspended organic and inorganic substances, substances that give unpleasant odors, bacteria, etc.). The high content of water in the sludge requires relatively large objects for sludge processing. This indicates the need for application procedures for treating sludge to volume reduce, stabilization of substances subject to decay and ...

  12. Sludge pumping in water treatment

    In water treatment processes is frequent to separate residual solids, with sludge shape, and minimize its volume in a later management. the technologies to applicate include pumping across pipelines, even to long distance. In wastewater treatment plants (WWTP), the management of these sludges is very important because their characteristics affect load losses calculation. Pumping sludge can modify its behavior and pumping frequency can concern treatment process. This paper explains advantages and disadvantages of different pumps to realize transportation sludge operations. (Author) 11 refs.

  13. Comparative Research on EPS Extraction from Mechanical Dewatered Sludge with Different Methods

    Weiyun Wang; Wanyu Liu; Lingyun Wang

    2015-01-01

    In order to find a suitable extracellular polymer substance (EPS) extraction method for mechanical dewatered sludge, four different methods including EDTA extraction, alkali extraction, acid extraction, ultrasonic extraction method have been used in extracting EPS from belt filter dewatered sludge. The contents of polysaccharide and proteins extracted from the dewatered sludge by different extraction methods are also analyzed. The results indicated that EDTA method and alkali extraction metho...

  14. Phytostabilization of mine tailings covered with fly ash and sewage sludge

    Neuschütz, Clara

    2009-01-01

    Establishing plant communities is essential for the restoration of contaminated land. As potential cover materials, fly ash and sewage sludge can prevent formation of acid mine drainage from sulfidic mine waste. The aim of the thesis was to i) screen for plants that can be established in, and prevent leakage of metals and nutrients from sludge on top of ash and tailings, and ii) investigate root growth into sealing layers of ash and sludge. Analyses were performed under laboratory, greenhouse...

  15. Sludge Batch 7 Preparation: Tank 4 And 12 Characterization

    Samples of PUREX sludge from Tank 4 and HM sludge from Tank 12 were characterized in preparation for Sludge Batch 7 (SB7) formulation in Tank 51. SRNL analyses on Tank 4 and Tank 12 were requested in separate Technical Assistance Requests (TAR). The Tank 4 samples were pulled on January 19, 2010 following slurry operations by F-Tank Farm. The Tank 12 samples were pulled on February 9, 2010 following slurry operations by H-Tank Farm. At the Savannah River National Laboratory (SRNL), two 200 mL dip samples of Tank 4 and two 200 mL dip samples of Tank 12 were received in the SRNL Shielded Cells. Each tank's samples were composited into clean 500 mL polyethylene storage bottles and weighed. The composited Tank 4 sample was 428.27 g and the composited Tank 12 sample was 502.15 g. As expected there are distinct compositional differences between Tank 4 and Tank 12 sludges. The Tank 12 slurry is much higher in Al, Hg, Mn, and Th, and much lower in Fe, Ni, S, and U than the Tank 4 slurry. The Tank 4 sludge definitely makes the more significant contribution of S to any sludge batch blend. This S, like that observed during SB6 washing, is best monitored by looking at the total S measured by digesting the sample and analyzing by inductively coupled plasma - atomic emission spectroscopy (ICPAES). Alternatively, one can measure the soluble S by ICP-AES and adjust the value upward by approximately 15% to have a pretty good estimate of the total S in the slurry. Soluble sulfate measurements by ion chromatography (IC) will be biased considerably lower than the actual total S, the difference being due to the non-sulfate soluble S and the undissolved S. Tank 12 sludge is enriched in U-235, and hence samples transferred into SRNL from the Tank Farm will need to be placed on the reportable special nuclear material inventory and tracked for total U per SRNL procedure requirements.

  16. Destroying lignocellulosic matters for enhancing methane production from excess sludge.

    Hao, Xiaodi; Hu, Yuansheng; Cao, Daqi

    2016-01-01

    A lot of lignocellulosic matters are usually present in excess sludge, which are hardly degraded in anaerobic digestion (AD) and thus remains mostly in digested sludge. This is a reason why the conversion rate of sludge organics into energy (CH4) is often low. Obviously, the hydrolysis of AD cannot destruct the structure of lignocellulosic matters. Structural destruction of lignocellulosic matters has to be performed in AD. In this study, pretreatments with the same principles as cell disintegration of sludge were applied to destruct lignocellulosic matters so that these materials could be converted to CH4 via AD. Acid, alkali, thermal treatment and ultrasonic were used in the experiments to observe the destructed/degraded efficiency of lignocellulosic matters. Thermal treatment was found to be the most effective pretreatment. Under optimized conditions (T = 150 °C and t = 30  min), pretreated sludge had a degraded rate of 52.6% in AD, due to easy destruction and/or degradation of hemicelluloses and celluloses in pretreatment. The sludge pretreated by thermal treatment could enhance the CH4 yield (mL CH4 g(-1) VSS) by 53.6% compared to raw sludge. Economically, the thermal treatment can balance the input energy with the produced energy (steam and electricity). PMID:26215289

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

    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

  18. Hydrogen utilization by clostridia in sewage sludge.

    Ohwaki, K; Hungate, R E

    1977-06-01

    A sporeformer morphologically different but physiologically similar to Clostridium aceticum Wieringa was isolated from sewage sludge. It used large amounts of H2 and CO2, converting them chiefly to acetic acid. Growth occurs anaerobically on yeast extract alone, but after the nutrients in yeast extract are used, growth continues at a reduced rate, supported by the conversion of the gases to acetate. PMID:879782

  19. Sewage sludges disinfection

    There is an hygienic risk in using biological sewage sludges for agriculture. Systematic analysis carried out on sludges samples obtained from purification plants in East and South part of France, show the almost uniform presence of pathogenic microorganisms. Some of it survive more than 9 months after soil application. Conventional process for disinfection: liming and heat are not suitable for agricultural use. On the other hand, irradiation involves no modification in structure and composition of sludges. Radiation doses required for disinfection vary according to microorganisms. If some of them are eliminated with rather light doses (200 krad) mycobacteria, viruses and eggs of worms resist to more important doses. Security dose is estimated around 1000 krad

  20. Bioventing PAH contamination at the Reilly Tar Site

    A pilot-scale bioventing demonstration has been in progress since November 1992 to determine if bioventing is an effective remediation treatment for polycyclic aromatic hydrocarbons (PAHs). The Reilly Tar and Chemical Corporation site in St. Louis Park, Minnesota, was selected for this demonstration. The location is the site of a former coal tar refinery and wood-preserving facility at which creosote in mineral oil served as the primary preservative. The goal of the project is to achieve 10% greater PAH removal over background degradation for each year of the 3-year study. Respiration measurements were made to estimate PAH biodegradation as a means of monitoring the progress of the technology. These measurements indicated that 13.4% and 17.3% degradation of the total PAH was possible during the first year and second year, respectively. Although not all of the respiration can be attributed conclusively to PAH metabolism, strong correlations were found between the PAH concentration and biodegradation rates

  1. Activated Sludge Rheology

    Ratkovich, Nicolas Rios; Horn, Willi; Helmus, Frank;

    2013-01-01

    Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling and...... filtration). It therefore is an important property related to process performance, including process economics. To account for this, rheological behaviour is being included in process design, necessitating its measurement. However, measurements and corresponding protocols in literature are quite diverse...

  2. Effects of birch tar oils on soil organisms and plants

    Hagner, Marleena; Pasanen, Tiina; Lindqvist, Bengt; Lindqvist, Isa; Tiilikkala, Kari; Penttinen, Olli-Pekka; Setala, Heikki

    2010-01-01

    The use of birch tar oil (BTO) is a new innovation in plant and animal protection working against various weeds, harmful insects and rodents. Due to its novelty as a biocide/repellent/plant protection product, no comprehensive information on the effects of BTO on non-target soil organisms is available. In this study we examined the impact of BTO on non-target soil organisms (enchytraeids, nematodes and soil microbes) and plants using laboratory toxicity tests and field experiments. In additio...

  3. HIV-1 nucleocapsid protein activates transient melting of least stable parts of the secondary structure of TAR and its complementary sequence.

    Bernacchi, Serena; Stoylov, Stoyl; Piémont, Etienne; Ficheux, Damien; Roques, Bernard P; Darlix, Jean Luc; Mély, Yves

    2002-03-29

    The nucleocapsid protein NCp7 of HIV-1 possesses a nucleic acid chaperone activity that is critical in minus and plus strand transfer during reverse transcription. The minus strand transfer notably relies on the ability of NCp7 to destabilize the stable stem with five contiguous, double-stranded segments of both the TAR sequence at the 3' end of the viral genome and the complementary sequence, cTAR, in minus strong-stop DNA. In order to examine the nature and the extent of NCp7 destabilizing activity, we investigated, by absorbance and fluorescence spectroscopy, the interaction of TAR and cTAR with a (12-55)NCp7 peptide containing the zinc-finger motifs but lacking the ability to aggregate the oligonucleotides. The absorbance changes in the UV band of cTAR show that seven to eight base-pairs, on average, are melted per oligonucleotide at a ratio of one peptide to 7.5 nucleotides. In contrast, the melting of TAR does not exceed an average of one base-pair per oligonucleotide. This may be linked to the greater stability of TAR, since a strong correlation between NCp7 destabilizing effect and oligonucleotide stability was observed. The effect of (12-55)NCp7 on the stem terminus was investigated by using a cTAR molecule doubly labeled at the 3' and 5' ends by a donor/acceptor couple. In the absence of the peptide, about 80 % of the oligonucleotides are in a dark non-fluorescent state, having a close proximity of the two dyes. The remaining 20 % are distributed between three fluorescent species, having either the terminal segment, the two terminal segments or all segments of the stem melted. This is in line with a fraying mechanism wherein the stem terminus fluctuates rapidly between open and closed states. Addition of (12-55)NCp7 shifts the equilibrium toward the open species, suggesting that NC enhances fraying of the stem terminus. Taken together, our data suggest that NCp7 activates the transient opening of base-pairs in the least stable parts of the stem. Also

  4. A portable system for decanting and packaging radioactive sludge

    Several spent fuel storage basins are maintained to support operation of the N Reactor for the U.S. Department of Energy. These basins have systems to filter and demineralize the basin cooling water, but they have not facilities to remove accumulated radioactive sludge on the bottom of the pool. The sludge becomes stirred up during fuel handling operations, thus obscuring vision and increasing the operator radiation exposure in the basin. The portable sludge removal system (SRS) was built to remove accumulated sludge, and decant, solidify, and package it in a form suitable for disposal. Because of the flexible design of the SRS, other applications that have been identified include particulate separation from neutralized waste acid and cleanup of outfall structures and solar evaporation ponds

  5. New technology for recyclingmaterials from oily cold rollingmill sludge

    Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Meng, Ling; Liu, Yang

    2013-12-01

    Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of "hydrometallurgical treatment + hydrothermal synthesis" was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.

  6. Hydraulic conductivity and soil-sewage sludge interactions

    Silvio Romero de Melo Ferreira

    2011-10-01

    Full Text Available One of the main problems faced by humanity is pollution caused by residues resulting from the production and use of goods, e.g, sewage sludge. Among the various alternatives for its disposal, the agricultural use seems promising. The purpose of this study was to evaluate the hydraulic conductivity and interaction of soil with sandy-silty texture, classified as Spodosols, from the Experimental Station Itapirema - IPA, in Goiana, state of Pernambuco, in mixtures with sewage sludge from the Mangueira Sewage Treatment Station, in the city of Recife, Pernambuco at rates of 25, 50 and 75 Mg ha-1. Tests were conducted to let water percolate the natural saturated soil and soil-sludge mixtures to characterize their physical, chemical, and microstructural properties as well as hydraulic conductivity. Statistical data analysis showed that the presence of sewage sludge in soils leads to an increase of the < 0.005 mm fraction, reduction in real specific weight and variation in optimum moisture content from 11.60 to 12.90 % and apparent specific dry weight from 17.10 and 17.50 kN m-3. In the sludge-soil mixture, the quartz grains were covered by sludge and filling of the empty soil macropores between grains. There were changes in the chemical characteristics of soil and effluent due to sewage sludge addition and a small decrease in hydraulic conductivity. The results indicate the possibility that soil acidity influenced the concentrations of the elements found in the leachate, showing higher levels at higher sludge doses. It can be concluded that the leaching degree of potentially toxic elements from the sewage sludge treatments does not harm the environment.

  7. Chemical conditioning of sludge

    Novak, John T.; Park, Chul

    2003-07-01

    With all the advances made in understanding the structure and composition of sewage sludges, chemical conditioning remains a trial and error process, both with regard to the type and dose of conditioner needed. Recent studies at Virginia Tech have found that biological floc consists of two types of biopolymer, material associated with iron and aluminum and material associated with calcium and magnesium. These materials behave differently when sludges undergo digestion. This results in very different material being released into solution during digestion and very different conditioning requirements. This study shows that the primary materials released during anaerobic digestion are proteins and coagulation of the colloidal protein fraction in solution is the primary mechanism for conditioning. For aerobically digested sludges, both proteins and polysaccharides make up the colloid fraction that interferes with dewatering. This research also shows that the effectiveness of the digestion process as characterized by volatile solids destruction is directly related to the chemical dose required for conditioning. That is, as the solids destruction increases, the conditioning chemical requirement also increases. Well-digested sludges dewater more poorly and require more conditioning chemical that those with less volatile solids destruction. (author)

  8. Chemical conditioning of sludge.

    Novak, J T; Park, C

    2004-01-01

    With all the advances made in understanding the structure and composition of sewage sludges, chemical conditioning remains a trial and error process, both with regard to the type and dose of conditioner needed. Recent studies at Virginia Tech have found that biological floc consists of two types of biopolymer, material associated with iron and aluminium and material associated with calcium and magnesium. These materials behave differently when sludges undergo digestion. This results in very different material being released into solution during digestion and very different conditioning requirements. This study shows that the primary materials released during anaerobic digestion are proteins and coagulation of the colloidal protein fraction in solution is the primary mechanism for conditioning. For aerobically digested sludges, both proteins and polysaccharides make up the colloid fraction, which interferes with dewatering. This research also shows that the effectiveness of the digestion process as characterized by volatile solids destruction is directly related to the chemical dose required for conditioning. That is, as the solids destruction increases, the conditioning chemical requirement also increases. Well digested sludges dewater more poorly and require more conditioning chemical than those with less volatile solids destruction. PMID:15259940

  9. Catalytic Pyrolysis of Olive Mill Wastewater Sludge

    Abdellaoui, Hamza

    2015-01-01

    Olive mill wastewater sludge (OMWS) is the solid residue that remains in the evaporation ponds after evaporation of the majority of water in the olive mill wastewater (OMW). OMWS is a major environmental pollutant in the olive oil producing regions. Approximately 41.16 wt. % of the OMWS was soluble in hexanes (HSF). The fatty acids in this fraction consist mainly of oleic and palmitic acid. Catalytic pyrolysis of the OMWS over red mud and HZSM-5 has been demonstrated to be an effective techno...

  10. Sewage sludge treatment system

    Kalvinskas, John J. (Inventor); Mueller, William A. (Inventor)

    1976-01-01

    Raw sewage may be presently treated by mixing screened raw sewage with activated carbon. The mixture is then allowed to stand in a first tank for a period required to settle the suspended matter to the bottom of the tank as a sludge. Thereafter, the remaining liquid is again mixed with activated carbon and the mixture is transferred to a secondary settling tank, where it is permitted to stand for a period required for the remaining floating material to settle as sludge and for adsorption of sewage carbon as well as other impurities to take place. The sludge from the bottom of both tanks is removed and pyrolyzed to form activated carbon and ash, which is mixed with the incoming raw sewage and also mixed with the liquid being transferred from the primary to the secondary settling tank. It has been found that the output obtained by the pyrolysis process contains an excess amount of ash. Removal of this excess amount of ash usually also results in removing an excess amount of carbon thereby requiring adding carbon to maintain the treatment process. By separately pyrolyzing the respective sludges from the first and second settling tanks, and returning the separately obtained pyrolyzed material to the respective first and second tanks from which they came, it has been found that the adverse effects of the excessive ash buildup is minimized, the carbon yield is increased, and the sludge from the secondary tank can be pyrolyzed into activated carbon to be used as indicated many more times than was done before exhaustion occurs.

  11. The assessment of sewage sludge gasification by-products toxicity by ecotoxicologial test.

    Werle, Sebastian; Dudziak, Mariusz

    2015-08-01

    The process of gasification of sewage sludge generates by-products, which may be contaminated with toxic and hazardous substances, both organic and inorganic. It is therefore important to assess the environmental risk associated with this type of waste. The feasibility of using an ecotoxicological tests for this purpose was determined in the presented study. The applied tests contained indicator organisms belonging to various biological groups (bacteria, crustaceans, plants). The subject of the study were solid (ash, char) and liquid (tar) by-products generated during gasification (in a fixed bed reactor) of dried sewage sludge from various wastewater treatment systems. The tested samples were classified based on their toxic effect. The sensitivity of the indicator organisms to the tested material was determined. In-house procedures for the preparation for toxicity analysis of both sewage sludge and by-products generated during the gasification were presented. The scope of work also included the determination of the effect of selected process parameters (temperature, amount of gasifying agent) on the toxicity of gasification by-products depending on the sewage sludge source. It was shown that both the type of sewage sludge and the parameters of the gasification process affects the toxicity of the by-products of gasification. However, the results of toxicity studies also depend on the type of ecotoxicological test used, which is associated with a different sensitivity of the indicator organisms. Nevertheless, it may be concluded that the by-products formed during the gasification of the low toxicity sewage sludge can be regarded as non-toxic or low toxic. However, the results analysis of the gasification of the toxic sludge were not conclusive, which leads to further research needs in this area. PMID:25827844

  12. Behavior of solid matters and heavy metals during conductive drying process of sewage sludge

    Jianping Luo

    2016-12-01

    Full Text Available Behavior of solid matters and heavy metals during conductive drying process of sewage sludge was evaluated in a sewage sludge disposal center in Beijing, China. The results showed most of solid matters could be retained in the dried sludge after drying. Just about 3.1% of solid matters were evaporated with steam mainly by the form of volatile fatty acids. Zn was the dominant heavy metal in the sludge, followed by Cu, Cr, Pb, Ni, Hg, and Cd. The heavy metals in the condensate were all below the detection limit except Hg. Hg in the condensate accounted for less than 0.1% of the total Hg. It can be concluded that most of the heavy metals are also retained in the dried sludge during the drying process, but their bioavailability could be changed significantly. The results are useful for sewage sludge utilization and its condensate treatment.

  13. Structural insights into the cTAR DNA recognition by the HIV-1 nucleocapsid protein: role of sugar deoxyriboses in the binding polarity of NC.

    Bazzi, Ali; Zargarian, Loussiné; Chaminade, Françoise; Boudier, Christian; De Rocquigny, Hughes; René, Brigitte; Mély, Yves; Fossé, Philippe; Mauffret, Olivier

    2011-05-01

    An essential step of the reverse transcription of the HIV-1 genome is the first strand transfer that requires the annealing of the TAR RNA hairpin to the cTAR DNA hairpin. HIV-1 nucleocapsid protein (NC) plays a crucial role by facilitating annealing of the complementary hairpins. Using nuclear magnetic resonance and gel retardation assays, we investigated the interaction between NC and the top half of the cTAR DNA (mini-cTAR). We show that NC(11-55) binds the TGG sequence in the lower stem that is destabilized by the adjacent internal loop. The 5' thymine interacts with residues of the N-terminal zinc knuckle and the 3' guanine is inserted in the hydrophobic plateau of the C-terminal zinc knuckle. The TGG sequence is preferred relative to the apical and internal loops containing unpaired guanines. Investigation of the DNA-protein contacts shows the major role of hydrophobic interactions involving nucleobases and deoxyribose sugars. A similar network of hydrophobic contacts is observed in the published NC:DNA complexes, whereas NC contacts ribose differently in NC:RNA complexes. We propose that the binding polarity of NC is related to these contacts that could be responsible for the preferential binding to single-stranded nucleic acids. PMID:21227929

  14. Who is actively denitrifying in activated sludge?

    Hansen, Aviaja Anna; Nielsen, Jeppe Lund

    -scale wastewater treatment plant the transcripts (mRNA) of the nirS, nirK and nosZ denitrification genes expressed under acetate or amino acid consumption were amplified, sequenced and identified. This revealed that the majority of the denitrifiers belonged to Alpha- and Betaproteobacteria, while only few...... genetic diversity was observed from the nirS transcripts and not the nosZ transcripts. Likewise, denitrifying cultures obtained from the activated sludge affiliated with the same Alpha- and Betaproteobacteria as detected with the denitrification genes, except one culture, which affiliated with...... Bacteroidetes. Furthermore, potential denitrifying genera of Alpha- and Betaproteobacteria were quantified in the activated sludge with 16S rRNA gene probes for fluorescence in situ hybridization (FISH). This revealed that Aquaspirillum-related bacteria were dominant followed by bacteria related to Azoarcus...

  15. Enzyme extraction by ultrasound from sludge flocs

    YU Guanghui; HE Pinjing; SHAO Liming; ZHU Yishu

    2009-01-01

    Enzymes play essential roles in the biological processes of sludge treatment. In this article, the ultrasound method to extract enzymes from sludge flocs was presented. Results showed that using ultrasound method at 20 kHz could extract more types of enzymes than that ultrasound at 40 kHz and ethylenediamine tetraacetic acid (EDTA) methods. The optimum parameters of ultrasound extraction at 20 kHz were duration of 10 min and power of 480 W. Under the condition, ultrasound could break the cells and extract both the extracellular and intercellular enzymes. Ultrasound power was apparently more susceptive to enzyme extraction than duration, suggesting that the control of power during ultrasound extraction was more important than that of duration. The Pearson correlation analysis between enzyme activities and cation contents revealed that the different types of enzymes had distinct cation binding characteristics.

  16. Structural features in TAR RNA of human and simian immunodeficiency viruses: a phylogenetic analysis.

    Berkhout, B.

    1992-01-01

    A comparative analysis of TAR RNA structures in human and simian immunodeficiency viruses reveals the conservation of certain structural features despite the divergence in sequence. Both the TAR elements of HIV-1 and SIV-chimpanzee can be folded into relatively simple one-stem hairpin structures. Chemical and RNAase probes were used to analyze the more complex structure of HIV-2 TAR RNA, which folds into a branched hairpin structure. A surprisingly similar RNA conformation can be proposed for...

  17. Radioactivity in sludge: tank cleaning procedures and sludge disposal

    In the oil and gas industry management of alpha-active sludge is made more complex by the presence of hydrocarbons and heavy metals. This presentation discusses the origin of radioactivity in sludge, management of risk in terms of safe working procedures, storage and possible disposal options. The several options will generally involve aspects of dilution or of concentration; issues to be discussed will include sludge farming, bioremediation and incineration. (author)

  18. Identification of sources of tar balls deposited along the Goa coast, India, using fingerprinting techniques

    Highlights: ► This is first fingerprinting study in India on identification of source of tar balls. ► Tar balls were formed from tanker-wash spills and they resemble floating tar ball. ► δ13C values of Bombay High crude oil and the present tar balls do not match. ► Compound specific stable carbon isotope analysis confirmed the source of tar balls. ► Source is confirmed as the South East Asian Crude Oil and not the Bombay High crude. -- Abstract: Deposition of tar balls along the coast of Goa, India is a common phenomenon during the southwest monsoon. Representative tar ball samples collected from various beaches of Goa and one Bombay High (BH) crude oil sample were subjected to fingerprint analysis based on diagnostic ratios of n-alkane, biomarkers of pentacyclic tri-terpanes and compound specific stable carbon isotope (δ13C) analysis to confirm the source. The results were compared with the published data of Middle East Crude Oil (MECO) and South East Asian Crude Oil (SEACO). The results revealed that the tar balls were from tanker-wash derived spills. The study also confirmed that the source is not the BH, but SEACO. The present study suggests that the biomarkers of alkanes and hopanes coupled with stable carbon isotope analysis act as a powerful tool for tracing the source of tar balls, particularly when the source specific biomarkers fail to distinguish the source

  19. Fungi tar degradation : possible application for micro-scale slow pyrolysis rotary kiln

    Petra Bozic

    2009-01-01

    When gas is cleaned in the process of slow pyrolysis in small-scale applications, water scrubbing is the most commonly used technology. After gas cleaning the tar and water vapors are trapped in the water, which is used for scrubbing. This waste water consists of condensed water vapoEndurnýjanleg orkars and two fractions of tar (water soluble and heavy tar). The product of this slow pyrolysis process is considered waste. None of the tar fractions are adequate for direct use in co-firing techn...

  20. Dermal uptake of polycyclic aromatic hydrocarbons after hairwash with coal-tar shampoo

    Schooten, F.-J. van; Moonen, E.J.C.; Rhijnsburger, E.; Agen, B. van; Thijssen, H.H.W.; Kleinjans, J.C.S. [University of Limburg, Maastricht (Netherlands). Dept. of Health Risk Analysis and Toxicology

    1994-11-26

    Describes an experiment to assess the dermal uptake of polycyclic aromatic hydrocarbons (PAHs) after hairwashing with coal tar antidandruff shampoo. The urinary excretion of 1-hydroxypyrene (1-OH-P), a PAH metabolile was used to assess internal dose of PAH. A single use of coal tar shampoo resulted in increased 1-OH-P excretion in all members of the experimental group compared with the control group using a non-coal tar antidandruff shampoo. It is suggested that repeated use of coal tar shampoo would result in a high internal dose of carcinogenic PAH. 5 refs., 1 fig.

  1. The Legend of Hot Tar or Pitch as a Defensive Weapon

    Atzbach, Rainer

    2015-01-01

    production and use during the Middle Ages will be discussed with special focus on the application of tar pitch as an ingredient in medieval and post-medieval thermal weapons (especially Greek Fire, the firebomb and the fire arrow). The punishment of tarring and feathering will also be considered. This......In popular culture and even in academic discourse surrounding castles, hot tar pitch has been depicted as a widespread defensive weapon. The identification of "machicoulis" (machicolations) as an architectural provision for pouring down liquid tar pitch goes back to the early days of castle...

  2. K Basins sludge removal temporary sludge storage tank system

    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

  3. K Basins sludge removal temporary sludge storage tank system

    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.

  4. Sewage sludge gasification in fluidized bed: influence of temperature and the stoichiometric relation; Gasificacion de fangos de depuradora en lecho fluidizado: influencia de la temperatura y de la relacion estequiometrica

    Manya, J.J.; Gonzalo, A.; Sanchez, J.L.; Arauzo, J. [Universidad de Zaragoza, Aragon (Spain). Inst. de Investigacion en Ingenieria. Grupo de Procesos Termoquimicos; Rocha, J.D. [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Nucleo Interdisciplinar de Planejamento Energetico (NIPE); Mesa Perez, J.M. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. de Engenharia Agricola (FEAGRI)

    2004-07-01

    The gasification of a dry granular sewage sludge has been experimentally studied. The gasification was carried out in a bench scale BFB facility, operated at steady state. The attention was focused on the presence of tar in the produced gas which affect the process efficiency and give negative drawbacks in the utilization in motors. The influence of two operating variables (bed temperature and equivalence ratio) on the gasification performances has been explored. Results show that the composition of produced gas is quite dependent of the variables analyzed. However, the results of tar yield show an unexpected behaviour. (author)

  5. The effect of composting on the organic colloidal fraction from domestic sewage sludge

    Almendros, Gonzalo; Leal, Juan A.; Martin, Francisco; Gonzalez-Vila, Francisco J.

    Due to the frequent use of domestic sewage sludges as organic additives to soils with low humus content, the chemical characteristics of the extractable polymers from composted and uncomposted sludges were described. The alkali-soluble, acid-insoluble sludge fraction (humic-like) was isolated after exhaustive lipid extraction, and analyzed by chemical degradation followed by combined gas chromatography mass spectrometry. It was observed that this sludge fraction contained an important amount of lipid compounds (more than 40% by weight). Most of this lipid material can be physically removed, but the residual polymer fractions were also found to be highly aliphatic in nature. The high yields upon degradation of several types of alkanoic acids and the relatively high proportion of polypeptides (30% by weight), as well as carbohydrates, suggested that the humic-like fractions from both the composted and uncomposted sludges consisted of slightly altered microbial and residual biopolymers. The effects of composting sludge mainly concern the selective biodegradation of the less resistant moieties. The great differences between the chemical nature of the humic-like fraction of the composted sludge and that of the soil humic acids are considered to reflect the low proportion of lignified materials in the original sludge.

  6. Pyrolysis gasification of dried sewage sludge in a combined screw and rotary kiln gasifier

    Chun, Young Nam; Kim, Seong Cheon [BK21 Team for Hydrogen Production, Department of Environmental Engineering, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of); Yoshikawa, Kunio [Frontier Research Center, Tokyo Institute of Technology, G5-8, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)

    2011-04-15

    A pyrolysis gasifier, with carbonization and activation steps, was developed to convert dried sludge into activated char and gas fuel energy. To determine the optimal driving conditions, parametric investigations were conducted on the amount of steam input, pyrolysis gasifier temperature and moisture content in the dried sludge. The optimal conditions for the dried sludge were found to be a steam input of 10 mL/min, gasifier temperature of 820 C and moisture content of 11% with a holding time in the pyrolysis gasifier of 1 h. The specific area of the activated char was 40.1 m{sup 2}/g, with an average pore diameter and volume of 63.49 Aa and 0.2354 cm{sup 3}/g, respectively. The pyrolysis gases were H{sub 2} (34.1%), CO (18.6%), CH{sub 4} (8.5%) and CO{sub 2} (8%). The higher heating value for the pyrolysis gas was 10,107 kJ/N m{sup 3}. To determine the tar adsorption characteristics, a benzene adsorption test was conducted using a fixed bed adsorption tower (H/D = 2, GHSV = 1175/h). The saturation point of the activated char was found after 45 min, and the amount of adsorption was 140 mg/g. Therefore, the pyrolysis gasification of sewage sludge can produce activated char which can be used to reduce tar, and gasification gas which can be utilized as a high enthalpy gas fuel. (author)

  7. SLUDGE BATCH 7B QUALIFICATION ACTIVITIES WITH SRS TANK FARM SLUDGE

    Pareizs, J.; Click, D.; Lambert, D.; Reboul, S.

    2011-11-16

    projected noble metals content for SB7b. Characterization was performed on the Tank 51 SB7b samples and SRNL performed DWPF simulations using the Tank 40 SB7b material. This report documents: (1) The preparation and characterization of the Tank 51 SB7b and Tank 40 SB7b samples. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the SB7b Tank 40 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a nonradioactive simulant. (3) Vitrification of a portion of the SME product and characterization and durability testing (as measured by the Product Consistency Test (PCT)) of the resulting glass. (4) Rheology measurements of the SRAT receipt, SRAT product, and SME product. This program was controlled by a Task Technical and Quality Assurance Plan (TTQAP), and analyses were guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R&D) for the DWPF. It should be noted that much of the data in this document has been published in interoffice memoranda. The intent of this technical report is bring all of the SB7b related data together in a single permanent record and to discuss the overall aspects of SB7b processing.

  8. Sludge Batch 7B Qualification Activities With SRS Tank Farm Sludge

    projected noble metals content for SB7b. Characterization was performed on the Tank 51 SB7b samples and SRNL performed DWPF simulations using the Tank 40 SB7b material. This report documents: (1) The preparation and characterization of the Tank 51 SB7b and Tank 40 SB7b samples. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the SB7b Tank 40 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a nonradioactive simulant. (3) Vitrification of a portion of the SME product and characterization and durability testing (as measured by the Product Consistency Test (PCT)) of the resulting glass. (4) Rheology measurements of the SRAT receipt, SRAT product, and SME product. This program was controlled by a Task Technical and Quality Assurance Plan (TTQAP), and analyses were guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R and D) for the DWPF. It should be noted that much of the data in this document has been published in interoffice memoranda. The intent of this technical report is bring all of the SB7b related data together in a single permanent record and to discuss the overall aspects of SB7b processing.

  9. [Detection of anaerobic processes and microorganisms in immobilized activated sludge of a wastewater treatment plant with intense aeration].

    Litti, Iu V; Nekrasova, V K; Kulikov, N I; Siman'kova, M V; Nozhevnikova, A N

    2013-01-01

    Attached activated sludge from the Krasnaya Polyana (Sochi) wastewater treatment plant was studied after the reconstruction by increased aeration and water recycle, as well as by the installation of a bristle carrier for activated sludge immobilization. The activated sludge biofilms developing under conditions of intense aeration were shown to contain both aerobic and anaerobic microorganisms. Activity of a strictly anaerobic methanogenic community was revealed, which degraded organic compounds to methane, further oxidized by aerobic methanotrophs. Volatile fatty acids, the intermediates of anaerobic degradation of complex organic compounds, were used by both aerobic and anaerobic microorganisms. Anaerobic oxidation of ammonium with nitrite (anammox) and the presence of obligate anammox bacteria were revealed in attached activated sludge biofilms. Simultaneous aerobic and anaerobic degradation of organic contaminants by attached activated sludge provides for high rates of water treatment, stability of the activated sludge under variable environmental conditions, and decreased excess sludge formation. PMID:25509405

  10. Agricultural yields of irradiated sewage sludge

    Lettuce, radish and ryegrass have been used to study the nitrogen fertilization of soil by sewage sludge. The results show that the irradiated sludge improve by 15 - 30 % the production yield, compared to the non-irradiated sludge. (author)

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

    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. Heavy metal sequestration by humic substances during phyto-treatment of sewage sludges

    The presence of heavy metals in sludges stabilized in a reed bed system, may affect their use for agricultural purposes; however, the environmental impact of sludges depends on the availability and phyto toxicity of their heavy metal. The aim of this paper was to determine the effectiveness of a reed bed (Phragmites Australia) sludge treatment system in two urban wastewater treatment plants in Italy after two-year period of operation: by estimating the process of sludge stabilization, following conventional and non conventional parameters related with the evolution of organic matter quality Water soluble Carbon, Dehydrogenase activity, Fulvic Acids, Humic Acids, Pyrolytic indices or organic matter Mineralization and Humification); by following the heavy metal speciation bioavailability in sludges. (Author)

  13. Structural and dynamic characterization of the upper part of the HIV-1 cTAR DNA hairpin

    Zargarian, Loussiné; Kanevsky, Igor; Bazzi, Ali; Boynard, Jonathan; Chaminade, Françoise; Fossé, Philippe; Mauffret, Olivier

    2009-01-01

    First strand transfer is essential for HIV-1 reverse transcription. During this step, the TAR RNA hairpin anneals to the cTAR DNA hairpin; this annealing reaction is promoted by the nucleocapsid protein and involves an initial loop–loop interaction between the apical loops of TAR and cTAR. Using NMR and probing methods, we investigated the structural and dynamic properties of the top half of the cTAR DNA (mini-cTAR). We show that the upper stem located between the apical and the internal loop...

  14. Production from multiple zones of a tar sands formation

    Karanikas, John Michael; Vinegar, Harold J

    2013-02-26

    A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat is allowed to transfer from the heaters to at least a portion of the formation. Fluids are produced from the formation through at least one production well that is located in at least two zones in the formation. The first zone has an initial permeability of at least 1 darcy. The second zone has an initial of at most 0.1 darcy. The two zones are separated by a substantially impermeable barrier.

  15. Podcast #5: Interview mit Mihara Ryôtarô

    Ryôtarô, Mihara; Offermann, Philipp

    2013-01-01

    Our most recent podcast: We were able to talk to the Japanese culturalanthropologist Mihara Ryôtarô while he visited Frankfurt in July for a talkon the Coool Japan Initiative [link]. As we have written on K-Pop in the past,we were very interested to talk about this kind of export promotion ofcultural goods as a foreign policy strategy: Do export subsidies of J-Popartifacts really promote Japanese soft power in the region? What are thedangers of promoting certain images of Japanese-ness? And i...

  16. Characterization of lorry washing sludge

    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...

  17. Faecal Sludge Management Systems

    Strande, Linda; Brdjanovic, Damir

    2014-01-01

    "It is estimated that literally billions of residents in urban and peri-urban areas of Africa, Asia, and Latin America are served by onsite sanitation systems (e.g. various types of latrines and septic tanks). Until recently, the management of faecal sludge from these onsite systems has been grossly neglected, partially as a result of them being considered temporary solutions until sewer-based systems could be implemented. However, the perception of onsite or decentralized sanitation technolo...

  18. Glazed Sludge Tile

    Dayalan J; Beulah. M

    2014-01-01

    In this article, glaze with different colorants was applied to tile specimens manufactured by incinerated sewage sludge ash (ISSA) and Clay. Improvements using different amounts of colorants, and glaze components and concentrations on tile bodies were investigated. Three different proportions of clay (by weight ratio) were replaced by ISSA. Tiles of size 10cm *10cm*1 cm were made and left in an electric furnace to make biscuit tiles at 800°C. Afterwards, four colorants, Fe2O3 ...

  19. Investigation of PHA Polymer Production from Sludge of Municipal Wastewater Treatment Plant and Its Effect on Sludge Volume Reduction

    N Mokhtarani

    2011-01-01

    Full Text Available "n "n "nBackgrounds and Objectives:Owing to the fact that the major environmental problem is production of surplus sludge in wastewater treatment plant, reducing the volume of produced sludge was objective of this research."nMaterials and Methods: An anaerobic-aerobic SBR with working volume of 10 L was used to make micro-organism adapted and a polymer production reactor (PPR with working volume of 1.5 L was used for producing polymer munisipal wastewater which contained different concentration of volatile fatty acids was consodered as the feed source (acetate and propionate and this system was evaluated with SRT of 5, 7 and 10 days."nResults: The maximum polymer production efficiency observed within 5 days (SRT=5 days though this efficiency was not significant in comparison with the two others time courses study. In this research the maximum polymer production efficiency at optimum condition was 25% of the sludge dry weight."nConclusion: Experiment revealed that producing polymer from activated sludge reduced the volume of sludge and the maximum reduced sludge volume was obtained 19%.

  20. Composting of sewage sludge irradiated

    Recently, the development of the techniques to return sewage sludge to forests and farm lands has been actively made, but it is necessary to assure its hygienic condition lest the sludge is contaminated by pathogenic bacteria. The research to treat sewage sludge by irradiation and utilize it as fertilizer or soil-improving material has been carried out from early on in Europe and America. The effects of the irradiation of sludge are sterilization, to kill parasites and their eggs, the inactivation of weed seeds and the improvement of dehydration. In Japan, agriculture is carried out in the vicinity of cities, therefore it is not realistic to use irradiated sludge for farm lands as it is. The composting treatment of sludge by aerobic fermentation is noticed to eliminate the harms when the sludge is returned to forests and farm lands. It is desirable to treat sludge as quickly as possible from the standpoint of sewage treatment, accordingly, the speed of composting is a problem. The isothermal fermentation experiment on irradiated sludge was carried out using a small-scale fermentation tank and strictly controlling fermentation conditions, and the effects of various factors on the fermentation speed were studied. The experimental setup and method are described. The speed of composting reached the maximum at 50 deg C and at neutral or weak alkaline pH. The speed increased with the increase of irradiation dose up to 30 Mrad. (Kako, I.)

  1. Sewage sludge disposal in Austria

    Sewage systems serve about 70% of the Austrian population, producing 6 million m3 of sewage sludge per year with a dry matter content of 4-5%. At present about 52% of this sludge is disposed of in land fills, 33% is incinerated, and only about 15 % is used in agriculture. Although agricultural utilization is becoming increasingly important, several problems, especially those related to public opinion, need to be resolved before increased use will be possible. In this paper, wastewater treatment and sewage-sludge production in Austria, and problems associated with sludge disposal are discussed. (author)

  2. Glazed Sludge Tile

    Dayalan J

    2014-03-01

    Full Text Available In this article, glaze with different colorants was applied to tile specimens manufactured by incinerated sewage sludge ash (ISSA and Clay. Improvements using different amounts of colorants, and glaze components and concentrations on tile bodies were investigated. Three different proportions of clay (by weight ratio were replaced by ISSA. Tiles of size 10cm *10cm*1 cm were made and left in an electric furnace to make biscuit tiles at 800°C. Afterwards, four colorants, Fe2O3 (red, V2O5 (yellow, and CoCO3 (blue and three different glaze concentrations were applied on biscuit tile specimens. These specimens were later sintered into glazed tiles at 1050°C. The study shows that replacement of clay by sludge ash had adverse effects on properties of tiles. Water absorption increased and bending strength reduced with increased amounts of sludge ash. However, both water absorption and bending strength improved for glazed ash tiles. Abrasion of grazed tiles reduced noticeably from 0.001 to 0.002 g. This implies glaze can enhance abrasion resistance of tiles.

  3. Activated Sludge Ozonation to Reduce Sludge Production in MBR

    HE Sheng-bing; XUE Gang; WANG Bao-zhen

    2005-01-01

    The total experimental period was divided into two stages.At the first stage, a series of batch studies were carried out to get an understanding of the effect of ozonation on sludge properties. At the following stages, three MBRs with different amounts of activated sludge to be ozonated were run in parallel for a long period to evaluate the influence of sludge ozonation on sludge yield and permeate quality.Through batch study, it was found that ozone could disrupt the cell walls and caused the release of plasm from the cells,then the amounts of soluble organics in the solution increased with ozonation time. With the rise of soluble organics, the amount of soluble organics to be mineralized increased as well, which wonld reduce the soluble organics content. For the counteraction between these two aspects, a pseudo-balance could be achieved, and soluble organics would vary in a limited range. Sludge ozonation also increased the contents of nitrogen and phosphorus in the solution. In addition, ozonation was effective in improving sludge settling property. On the basis of batch study, a suitable ozone dosage of 0.16 kgO3/kgMLSS wasdetermined. Three systems were run in parallel for a total period of 39 days, it was demonstrated that a part of activated sludge ozonation could reduce sludge production significantly, and biological performance of mineralization and nitrification would not be inhibited due to sludge ozonation. Experimental results proved that the combination of ozonation unit with MBR unit could achieve an excellent quality of permeate as well as a small quantity of sludge production, and economic analysis indicated that an additional ozonation operating cost for treatment of both wastewater and sludge was only 0.096Yuan (US $0.011,5)/m3 wastewater.

  4. Sludge Washing And Demonstration Of The DWPF Flowsheet In The SRNL Shielded Cells For Sludge Batch 6 Qualification

    Prior to initiating a new sludge batch in the Defense Waste Processing Facility (DWPF), Savannah River National Laboratory (SRNL) is required to simulate this processing, including Chemical Process Cell (CPC) simulation, waste glass fabrication, and chemical durability testing. This report documents this simulation for the next sludge batch, Sludge Batch 6 (SB6). SB6 consists of Tank 12 material that has been transferred to Tank 51 and subjected to Low Temperature Aluminum Dissolution (LTAD), Tank 4 sludge, and H-Canyon Pu solutions. Following LTAD and the Tank 4 addition, Liquid Waste Operations (LWO) provided SRNL a 3 L sample of Tank 51 sludge for SB6 qualification. Pu solution from H Canyon was also received. SB6 qualification included washing the sample per LWO plans/projections (including the addition of Pu from H Canyon), DWPF CPC simulations, waste glass fabrication (vitrification), and waste glass characterization and chemical durability evaluation. The following are significant observations from this demonstration. Sludge settling improved slightly as the sludge was washed. SRNL recommended (and the Tank Farm implemented) one less wash based on evaluations of Tank 40 heel projections and projections of the glass composition following transfer of Tank 51 to Tank 40. Thorium was detected in significant quantities (>0.1 wt % of total solids) in the sludge. In past sludge batches, thorium has been determined by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS), seen in small quantities, and reported with the radionuclides. As a result of the high thorium, SRNL-AD has added thorium to their suite of Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) elements. The acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT) processing of 115%, or 1.3 mol acid per liter of SRAT receipt slurry, was adequate to accomplish some of the goals of SRAT processing: nitrite was destroyed to below 1,000 mg/kg and mercury was removed to

  5. Metaproteomics provides functional insight into activated sludge wastewater treatment.

    Paul Wilmes

    Full Text Available BACKGROUND: Through identification of highly expressed proteins from a mixed culture activated sludge system this study provides functional evidence of microbial transformations important for enhanced biological phosphorus removal (EBPR. METHODOLOGY/PRINCIPAL FINDINGS: A laboratory-scale sequencing batch reactor was successfully operated for different levels of EBPR, removing around 25, 40 and 55 mg/l P. The microbial communities were dominated by the uncultured polyphosphate-accumulating organism "Candidatus Accumulibacter phosphatis". When EBPR failed, the sludge was dominated by tetrad-forming alpha-Proteobacteria. Representative and reproducible 2D gel protein separations were obtained for all sludge samples. 638 protein spots were matched across gels generated from the phosphate removing sludges. 111 of these were excised and 46 proteins were identified using recently available sludge metagenomic sequences. Many of these closely match proteins from "Candidatus Accumulibacter phosphatis" and could be directly linked to the EBPR process. They included enzymes involved in energy generation, polyhydroxyalkanoate synthesis, glycolysis, gluconeogenesis, glycogen synthesis, glyoxylate/TCA cycle, fatty acid beta oxidation, fatty acid synthesis and phosphate transport. Several proteins involved in cellular stress response were detected. CONCLUSIONS/SIGNIFICANCE: Importantly, this study provides direct evidence linking the metabolic activities of "Accumulibacter" to the chemical transformations observed in EBPR. Finally, the results are discussed in relation to current EBPR metabolic models.

  6. Quantitative group-type analysis of coal-tar pitches

    Membrado, L.; Cebolla, V.L.; Vela, J. [Instituto de carboquimica, Zaragoza (Spain)

    1995-12-31

    Preparative liquid chromatographic (LC) and related techniques (e.g.., extrography) are mostly used for quantitative compound class or group-type analysis of coal-tar pitches. TLC-FID has hardly been used for this purpose because of the time-consuming calibration steps required. As the FID response of each peak depends on its nature, the classical approach in fossil fuel analysis to a quantitative analysis is the absolute calibration using fractions derived from the fossil fuel itself (previously isolated by LC) as external standards. An added problem is the isolation of these fractions with the required purity. A TLC-FID system has previously been described in this issue, which gives adequate repeatability and precision, and gives a quantitative FID response. In this work, a rapid calibration procedure which allows a quantitative group-type analysis of a whole coal-tar pitch (without any prefractionation) using TLC-FID is presented as an alternative to absolute calibration. This method considerably reduces the total time of analysis. Likewise, the use of TLC-FID as a monitoring technique to improve the classical absolute calibration is also proposed. Pros and cons of group-type analysis techniques are finally discussed with regard to TLC-FID.

  7. Evaluation of different oxygen carriers for biomass tar reforming

    Mendiara, Teresa; Johansen, Joakim Myung; Utrilla, Rubén;

    2011-01-01

    This work is a continuation of a previous paper by the authors [1] which analyzed the suitability of the Chemical Looping technology in biomass tar reforming. Four different oxygen carriers were tested with toluene as tar model compound: 60% NiO/MgAl2O4 (Ni60), 40% NiO/NiAl2O4 (Ni40), 40% Mn3O4/Mg......–ZrO2 (Mn40) and FeTiO3 (Fe) and their tendency to carbon deposition was analyzed in the temperature range 873–1073K. In the present paper, the reactivity of these carriers to other compounds in the gasification gas is studied, also with special emphasis on the tendency to carbon deposition. Experiments...... were carried out in a TGA apparatus and a fixed bed reactor. Ni-based carriers showed a tendency to form carbon in the reaction with CH4, especially Ni60. The addition of water in H2O/CH4 molar ratios of 0.4–2.3 could decrease the carbon deposited, but not in the case of Ni60. Mn-based sample reacted...

  8. Combined free nitrous acid and hydrogen peroxide pre-treatment of waste activated sludge enhances methane production via organic molecule breakdown

    Zhang, Tingting; Wang, Qilin; Ye, Liu; Batstone, Damien; Yuan, Zhiguo

    2015-11-01

    This study presents a novel pre-treatment strategy using combined free nitrous acid (FNA i.e. HNO2) and hydrogen peroxide (H2O2) to enhance methane production from WAS, with the mechanisms investigated bio-molecularly. WAS from a full-scale plant was treated with FNA alone (1.54 mg N/L), H2O2 alone (10-80 mg/g TS), and their combinations followed by biochemical methane potential tests. Combined FNA and H2O2 pre-treatment substantially enhanced methane potential of WAS by 59-83%, compared to 13-23% and 56% with H2O2 pre-treatment alone and FNA pre-treatment alone respectively. Model-based analysis indicated the increased methane potential was mainly associated with up to 163% increase in rapidly biodegradable fraction with combined pre-treatment. The molecular weight distribution and chemical structure analyses revealed the breakdown of soluble macromolecules with the combined pre-treatment caused by the deamination and oxidation of the typical functional groups in proteins, polysaccharides and phosphodiesters. These changes likely improved the biodegradability of WAS.

  9. Structural Analysis of the Ligand-Binding Domain of the Aspartate Receptor Tar from Escherichia coli.

    Mise, Takeshi

    2016-07-01

    The Escherichia coli cell-surface aspartate receptor Tar mediates bacterial chemotaxis toward an attractant, aspartate (Asp), and away from a repellent, Ni(2+). These signals are transmitted from the extracellular region of Tar to the cytoplasmic region via the transmembrane domain. The mechanism by which extracellular signals are transmitted into the cell through conformational changes in Tar is predicted to involve a piston displacement of one of the α4 helices of the homodimer. To understand the molecular mechanisms underlying the induction of Tar activity by an attractant, the three-dimensional structures of the E. coli Tar periplasmic domain with and without bound aspartate, Asp-Tar and apo-Tar, respectively, were determined. Of the two ligand-binding sites, only one site was occupied, and it clearly showed the electron density of an aspartate. The slight changes in conformation and the electrostatic surface potential around the aspartate-binding site were observed. In addition, the presence of an aspartate stabilized residues Phe-150' and Arg-73. A pistonlike displacement of helix α4b' was also induced by aspartate binding as predicted by the piston model. Taken together, these small changes might be related to the induction of Tar activity and might disturb binding of the second aspartate to the second binding site in E. coli. PMID:27292793

  10. Solid state 13 C NMR quantitative study of wood tar pitches

    In this work, solid-state 13 C NMR is used with other techniques to characterize Eucalyptus tar pitches and to follow their polymerization reactions. The pitches are the residues of distillation (about 50% m;m) of the tar generated in Eucalyptus slow pyrolysis for charcoal production in metal industry

  11. Gas chromatographic-mass spectrometric analysis of tar compounds formed during pyrolysis of rice husks

    Haanappel, V.A.C.; Stevens, T.W.; Hovestad, A.; Skolnik, V.; Visser, R.

    1991-01-01

    Pyrolysis of agricultural waste to produce fuel gas involves formation of tars as noxious by-products. In this paper the qualitative analysis of tars formed during pyrolysis of rice husks is presented, based on identification by gas chromatography—mass spectrometry and interpolation of retention tim

  12. Estimating release of polycyclic aromatic hydrocarbons from coal tar at manufactured-gas plant sites

    One component of the EPRI's research on Envirorunental Behavior of Organic Substances (EBOS) consists of developing information and models to predict releases of monocyclic and polycyclic aromatic hydrocarbons (MAHs and PAHs) to groundwater from coal tars and contaminated soils at MGP sites. The results of this report focus primarily on release of PAHs from coal tars. There are at least two approaches to predicting the release of organic chemicals from coal tar to water. The simplest method to estimate aqueous concentrations is to assume that water solubility of a PAH compound released from the tar can be defined by equilibrium precipitation-dissolution reactions. Application of Raoult's law is another method to predict aqueous concentrations, which requires the assumption of ''ideal'' behavior for partitioning of PAHs between the tar and water phases. To evaluate the applicability of these two methods for predicting PAH releases, laboratory experiments were conducted with eight coal tar samples from former MGP sites across the country. Migration of chemicals in the environment and resulting contaminant plumes in groundwater are determined by leachate concentrations of the chemicals. The use of equilibrium precipitation-dissolution reactions will usually result in an overestimation of PAH concentrations in the leachate from a coal tar source, and thus the resulting PAH concentrations in groundwater. Raoult's law appears to be a more accurate approach to predicting the release of several PAHs from coal tars. Furthermore, if nonequilibrium conditions prevail, aqueous-phase PAH concentrations will be even lower than those predicted using Raoult's law

  13. Utilization of AMD sludges from the anthracite region of Pennsylvania for removal of phosphorus from wastewater

    Sibrell, P.L.; Cravotta, C.A., III; Lehman, W.G.; Reichert, W.

    2010-01-01

    Excess phosphorus (P) inputs from human sewage, animal feeding operations, and nonpoint source discharges to the environment have resulted in the eutrophication of sensitive receiving bodies of water such as the Great Lakes and Chesapeake Bay. Phosphorus loads in wastewater discharged from such sources can be decreased by conventional treatment with iron and aluminum salts but these chemical reagents are expensive or impractical for many applications. Acid mine drainage (AMD) sludges are an inexpensive source of iron and aluminum hydrous oxides that could offer an attractive alternative to chemical reagent dosing for the removal of P from local wastewater. Previous investigations have focused on AMD sludges generated in the bituminous coal region of western Pennsylvania, and confirmed that some of those sludges are good sorbents for P over a wide range of operating conditions. In this study, we sampled sludges produced by AMD treatment at six different sites in the anthracite region of Pennsylvania for potential use as P sequestration sorbents. Sludge samples were dried, characterized, and then tested for P removal from water. In addition, the concentrations of acid-extractable metals and other impurities were investigated. Test results revealed that sludges from four of the sites showed good P sorption and were unlikely to add contaminants to treated water. These results indicate that AMD sludges could be beneficially used to sequester P from the environment, while at the same time decreasing the expense of sludge disposal.

  14. Nitrogen availability of anaerobic swine lagoon sludge: sludge source effects.

    Moore, Amber D; Israel, Daniel W; Mikkelsen, Robert L

    2005-02-01

    Increased numbers of swine producers will be removing sludge from their anaerobic waste treatment lagoons in the next few years, due to sludge exceeding designed storage capacity. Information on availability of nitrogen (N) in the sludge is needed to improve application recommendations for crops. The objective of this study was to investigate possible effects of different companies and types of swine operations on the availability of N in sludge from their associated lagoons. A laboratory incubation study was conducted to quantify the availability of N (i.e. initial inorganic N plus the potentially mineralizable organic N) in the sludge. Nine sludge sources from lagoons of sow, nursery and finishing operations of three different swine companies were mixed with a loamy sand soil (200 mg total Kjeldahl N kg(-1) soil) and incubated at a water content of 0.19 g. water g(-1) dry soil and 25+/-2 degrees C for 12 weeks. Samples were taken at eight times over the 12-week period and analyzed for inorganic N (i.e. NH(4)-N and NO(3)-N) to determine mineralization of organic N in the sludge. Company and type of swine operation had no significant effects (P incubation. While plant N availability coefficients were not measured in this study, the lack of significant company or type of swine operation effects on sludge N mineralization suggests that use of the same plant N availability coefficient for sludge from different types of lagoons is justifiable. The validity of this interpretation depends on the assumption that variation in other components of different sludge sources such as Cu and Zn does not differentially alter N uptake by the receiver crops. PMID:15474933

  15. Determination of the acidic sites of purified single-walled carbon nanotubes by acid base titration

    Hu, H.; Bhowmik, P.; Zhao, B.; Hamon, M. A.; Itkis, M. E.; Haddon, R. C.

    2001-09-01

    We report the measurement of the acidic sites in three different samples of commercially available full-length purified single-walled carbon nanotubes (SWNTs) - as obtained from CarboLex (CLI), Carbon Solutions (CSI) and Tubes@Rice (TAR) - by simple acid-base titration methods. Titration of the purified SWNTs with NaOH and NaHCO 3 solutions was used to determine the total percentage of acidic sites and carboxylic acid groups, respectively. The total percentage of acidic sites in full length purified SWNTs from TAR, CLI and CSI are about 1-3%.

  16. Sludge Treatment Evaluation: 1992 Technical progress

    This report documents Fiscal Year 1992 technical progress on the Sludge Treatment Evaluation Task, which is being conducted by Pacific Northwest Laboratory. The objective of this task is to develop a capability to predict the performance of pretreatment processes for mixed radioactive and hazardous waste stored at Hanford and other US Department of Energy (DOE) sites. Significant cost savings can be achieved if radionuclides and other undesirable constituents can be effectively separated from the bulk waste prior to final treatment and disposal. This work is initially focused on chemical equilibrium prediction of water washing and acid or base dissolution of Hanford single-shell tank (SST) sludges, but may also be applied to other steps in pretreatment processes or to other wastes. Although SST wastes contain many chemical species, there are relatively few constituents -- Na, Al, NO3, NO2, PO4, SO4, and F -- contained in the majority of the waste. These constituents comprise 86% and 74% of samples from B-110 and U-110 SSTS, respectively. The major radionuclides of interest (Cs, Sr, Tc, U) are present in the sludge in small molal quantities. For these constituents, and other important components that are present in small molal quantities, the specific ion-interaction terms used in the Pitzer or NRTL equations may be assumed to be zero for a first approximation. Model development can also be accelerated by considering only the acid or base conditions that apply for the key pretreatment steps. This significantly reduces the number of chemical species and chemical reactions that need to be considered. Therefore, significant progress can be made by developing all the specific ion interactions for a base model and an acid dissolution model

  17. Sludge Digestion Manual; Handboek Slibgisting

    NONE

    2011-09-15

    This manual offers a guideline for developing, designing, optimizing and operating sludge digestion installations based on sewage sludge. It also offers tools for solving operation problems [Dutch] Het Handboek is een leidraad voor het ontwikkelen, ontwerpen, optimaliseren en bedrijven van slibgistingsinstallaties voor zuiveringsslib. Ook geeft het handvatten voor het oplossen van operationele problemen.

  18. RECLAMATION OF ALUMINUM FINISHING SLUDGES

    The research study of the reclamation of aluminum-anodizing sludges was conducted in two sequential phases focused on enhanced dewatering of aluminum-anodizing sludges to produce commercial-strength solutions of aluminum sulfate, i.e., liquid alum. The use of high-pressure (14 to...

  19. Microwave-induced cracking of pyrolytic tars coupled to microwave pyrolysis for syngas production.

    Beneroso, D; Bermúdez, J M; Montes-Morán, M A; Arenillas, A; Menéndez, J A

    2016-10-01

    Herein a new process is proposed to produce a syngas-rich gas fraction (>80vol% H2+CO) from biowaste based on microwave heating within two differentiated steps in order to avoid tars production. The first step consists of the microwave pyrolysis of biowaste induced by a char-based susceptor at 400-800°C; tars, char and syngas-rich gas fractions being produced. The tars are then fed into the second step where a portion of the char from the first step is used as a bed material in a 0.3:1wt% ratio. This bed is heated up by microwaves up to 800°C, allowing thermal cracking of tars and additional syngas (>90vol% H2+CO) being then produced. This new concept arises as an alternative technology to the gasification of biowastes for producing syngas with no need for catalysts or gasifying reagents to minimise tars production. PMID:27420155

  20. Decomposition of tar in gas from updraft gasifier by thermal cracking

    Brandt, Peder; Henriksen, Ulrik Birk

    2000-01-01

    Continuing earlier work with tar reduction by partial oxidation of pyrolysis gas [1] thermal cracking has been evaluated as a gas cleaning process. The work has been focusing on cleaning gas from updraft gasifiers, and the long term purpose is to develop a tar cleaning unit based on thermal...... low as 15 mg/Nm3 was obtained on gas from an updraft gasifier. The lower heating value of the cleaned gas was 6.0 MJ/Nm3, and the energy content of the non condensable gasses was 19% higher than before cracking....... was 1200, 1250 and 1290°C, and the residence time at this temperature was 0.5 second. The measurements show that at the selected residence time of 0.5 second, the gas flow in a thermal tar cracking unit has to be heated to at least 1250°C to achieve sufficient tar cleaning. At 1290°C, a tar content as...

  1. The influence of partial oxidation mechanisms on tar destruction in TwoStage biomass gasification

    Ahrenfeldt, Jesper; Egsgaard, Helge; Stelte, Wolfgang;

    2013-01-01

    TwoStage gasification of biomass results in almost tar free producer gas suitable for multiple end-use purposes. In the present study, it is investigated to what extent the partial oxidation process of the pyrolysis gas from the first stage is involved in direct and in-direct tar destruction and...... conversion. The study identifies the following major impact factors regarding tar content in the producer gas: oxidation temperature, excess air ratio and biomass moisture content. In a experimental setup, wood pellets were pyrolyzed and the resulting pyrolysis gas was transferred in a heated partial...... resulting PAH tar compounds are readily converted in the subsequent char-bed of the TwoStage gasification process and the partial oxidation process thus contributes directly as well as in-directly to the overall tar destruction. A high temperature and excess air ratios contribute positively to the direct...

  2. Study of thermal reactivity of brown coal tars from rapid and slow pyrolysis

    Teubel, J.; Rast, A.; Schmiers, H.; Scholze, S. (Bergakademie, Freiberg (German Democratic Republic))

    1990-01-01

    Analyzes differences in properties of brown coal tars produced from coal of the same deposit, but using either rapid or slow pyrolysis. Samples of rapid pyrolysis tar originated from laboratory fluidized bed carbonization; the slow pyrolysis tar came from industrial brown coal coking. The study showed that rapid pyrolysis tar has a high thermal reactivity in the 400 C temperature range. Obtained pitch from thermal tar treatment has a high content of asphaltenes and benzene insoluble compounds. Electrode coke produced by carbonization of this pitch had an unfavorable microstructure and is unsuitable for graphitization. Secondary pyrolysis is therefore required to gain rapid pyrolysis pitch comparable in properties to pitch from industrial slow pyrolysis. 4 refs.

  3. Structural determinants of TAR RNA-DNA annealing in the absence and presence of HIV-1 nucleocapsid protein

    Kanevsky, Igor; Chaminade, Françoise; Chen, Yingying; Godet, Julien; René, Brigitte; Darlix, Jean-Luc; Mély, Yves; Mauffret, Olivier; Fossé, Philippe

    2011-01-01

    Annealing of the TAR RNA hairpin to the cTAR DNA hairpin is required for the minus-strand transfer step of HIV-1 reverse transcription. HIV-1 nucleocapsid protein (NC) plays a crucial role by facilitating annealing of the complementary hairpins. To gain insight into the mechanism of NC-mediated TAR RNA–DNA annealing, we used structural probes (nucleases and potassium permanganate), gel retardation assays, fluorescence anisotropy and cTAR mutants under conditions allowing strand transfer. In t...

  4. Core competency needs analysis for U.S. naval reserve training and administration Of reserve (TAR) officers

    Newman, Carol E.

    2002-01-01

    Approved for public release; distribution is unlimited This thesis identifies fundamental Reserve management-related core competencies required for Training and Administration of the Reserve (TAR) officers. In-depth interviews were conducted with 21 experienced TAR officers who defined and described essential competencies for TAR officers. Additionally, they identified competency gaps and offered recommendations as to how TAR officers could better develop the competencies. Based on the ana...

  5. Extraction kinetics of heavy metal-containing sludge.

    Lee, I-Hsien; Wang, Yi-Jing; Chern, Jia-Ming

    2005-08-31

    In order to remove and recover copper, zinc, cadmium, and chromium from the wastewater treatment sludge generated by an electroplating process, the heavy metal extraction kinetics was studied in a batch reactor using two different extraction agents (nitric and citric acid) at constant agitation speed (150 rpm) and solid to liquid ratio (10 g/L), but varying acid concentrations (0.02-0.10 N), temperatures (25-85 degrees C in nitric acid solution, 25-95 degrees C in citric acid solution), and sludge particle sizes. The shrinking-core model and empirical kinetic model were adopted to analyze the experimental data. Although both models could fit the experimental kinetic data well, the obtained parameters of the shrinking-core model did not show reasonable trends varying with the experimental variables while the empirical model parameters showed significant trends. The experimental and modeling results showed that the metal extraction rates increased with acid concentration, temperature, but decreased with increasing particle size. Nitric acid was found to be more effective than citric acid to extract the heavy metals from the sludge. The extraction activation energies obtained in this study suggested that both a physical diffusion process and a chemical reaction process might play important roles in the overall extraction process. PMID:15993295

  6. Separation of coal tar fractions by solvent extraction - Extractant/solvent separation by secondary extraction

    Salim, C.; Saito, J.; Egashira, R. [Tokyo Institute of Technology, Tokyo (Japan). Graduate School of Science & Engineering

    2005-01-15

    Solvent extraction was applied to the separation of tar light oil and absorption oil, and solvent recovery in the separation of these coal tar fractions by extraction with secondary oil solvent. The liquid-liquid equilibria were measured with various combinations of oil and aqueous methanol phases that occur throughout the whole extraction process. Based on the equilibrium results, a process separating absorption oil and tar light oil simultaneously with a single aqueous solvent is suggested, in which the two feed oils also act as secondary solvents for mutual separation. In the separation of feed oils by aqueous methanol solution as solvent, nitrogen heterocyclic compounds in the absorption oil and the tar light oil were extracted preferentially to other compounds including homocyclic hydrocarbons and oxygen heterocyclic compounds. In the solvent recovery in the separation of absorption oil, the aqueous extract phase containing aqueous solvent and extractants was separated by tar light oil as secondary oil solvent. In the solvent recovery in the separation of tar light oil, the aqueous extract phase was separated by absorption oil as the secondary oil solvent. The distribution coefficients were not affected by the type of oil phase of coal tar fraction and by the presence of the extractants in the aqueous phase. The distribution coefficients in all cases of oil phases of absorption oil and tar light oil could be classified into three groups: monocyclic nitrogen compounds, bicyclic nitrogen compounds, and other compounds including hydrocarbons and oxygen compounds. By integrating the two separation processes of absorption oil and tar light oil into one process separating both coal tar fractions simultaneously with a single aqueous solvent, several extractors and solvents required in the two separate processes can be eliminated.

  7. Ultrasonic sludge pretreatment under pressure.

    Le, Ngoc Tuan; Julcour-Lebigue, Carine; Delmas, Henri

    2013-09-01

    The objective of this work was to optimize the ultrasound (US) pretreatment of sludge. Three types of sewage sludge were examined: mixed, secondary and secondary after partial methanisation ("digested" sludge). Thereby, several main process parameters were varied separately or simultaneously: stirrer speed, total solid content of sludge (TS), thermal operating conditions (adiabatic vs. isothermal), ultrasonic power input (PUS), specific energy input (ES), and for the first time external pressure. This parametric study was mainly performed for the mixed sludge. Five different TS concentrations of sludge (12-36 g/L) were tested for different values of ES (7000-75,000 kJ/kgTS) and 28 g/L was found as the optimum value according to the solubilized chemical oxygen demand in the liquid phase (SCOD). PUS of 75-150 W was investigated under controlled temperature and the "high power input - short duration" procedure was the most effective at a given ES. The temperature increase in adiabatic US application significantly improved SCOD compared to isothermal conditions. With PUS of 150 W, the effect of external pressure was investigated in the range of 1-16 bar under isothermal and adiabatic conditions for two types of sludge: an optimum pressure of about 2 bar was found regardless of temperature conditions and ES values. Under isothermal conditions, the resulting improvement of sludge disintegration efficacy as compared to atmospheric pressure was by 22-67% and 26-37% for mixed and secondary sludge, respectively. Besides, mean particle diameter (D[4,3]) of the three sludge types decreased respectively from 408, 117, and 110 μm to about 94-97, 37-42, and 36-40 μm regardless of sonication conditions, and the size reduction process was much faster than COD extraction. PMID:23587728

  8. Relationship between organic matter humification and bioavailability of sludge-borne copper and cadmium during long-term sludge amendment to soil.

    Liu, Hongtao

    2016-10-01

    Recycling of sludge as soil amendment poses certain risk of heavy metals contamination. This study investigated the relationship between organic matter in composted sludge and its heavy metals bioavailability over 7years. Periodic monitoring indicated a gradual increase in organic matter degradation, accompanied by changing degrees of polymerization, i.e., ratio of humic acid (HA)/fulvic acid (FA) coupled with incremental exchangeable fraction of copper (Cu) in sludge, with a growing rate of 74.7%, rather than that in soil. However, cadmium (Cd) in composted sludge exhibited an independent manner. Linear-regression analysis revealed that the total proportion of the Cu active fraction (exchangeable plus carbonate bound) was better correlated with the degree of polymerization (DP) and humification ratio (HR) than the degradation ratio of organic matter. Overall, amount of uptaken Cu was more dependent on the humification degree of organic matter, especially the proportion of HA in humus. PMID:27208784

  9. A Technology of Wastewater Sludge Treatment

    Gizatulin, R. A.; Senkus, V. V.; Valueva, A. V.; Baldanova, A. S.; Borovikov, I. F.

    2016-04-01

    At many communities, industrial and agricultural enterprises, treatment and recycling of wastewater sludge is an urgent task as the sludge is poured and stored in sludge banks for many years and thus worsens the ecology and living conditions of the region. The article suggests a new technology of wastewater sludge treatment using water-soluble binder and heat treatment in microwave ovens.

  10. Occurrence and fate of perfluorinated compounds in sewage sludge from Spain and Germany.

    Gómez-Canela, Cristian; Barth, Johannes A C; Lacorte, Silvia

    2012-11-01

    Perfluorinated compounds (PFCs) are persistent and bioaccumulative organic compounds used as additives in many industrial products. After use, these compounds enter wastewater treatment plants (WWTP) and long-chain PFCs are primarily accumulated in sludge. The aim of this study was to determine the occurrence and behavior of five PFCs in sludge from 15 WWTP from Spain and Germany that receive both urban and industrial wastes. The PFCs studied were perfluorooctanesulfonate (PFOS), perfluorohexanesulfonate (PFHxS), perfluorobutanesulfonate (PFBS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA). One gram of freeze-dried, sieved, and homogenized sludge was extracted using an ultrasonic bath with methanol and glacial acetic acid. After that, the extract was recovered and evaporated to dryness with a TurboVap and then 1 mL of acetonitrile was added and the extract was cleaned up with black carbon. Liquid chromatography coupled to mass spectrometry operated in selected reaction monitoring was used to determine target compounds. Quality parameters are provided for the set of compounds studied. PFCs were detected in all samples. In Spanish sludge, ∑PFC ranged from 0.28 to 5.20 ng/g dry weight (dw) with prevalence of PFOS, while in German sludge, ∑PFC ranged from 20.7 to 38.6 ng/g dw and PFBS was the dominant compound. As a next step, the evolution of PFC concentrations within the sludge treatment steps (primary sludge, anaerobic digested sludge, and centrifuged sludge) was evaluated and differences among levels and patterns were observed and were attributed to the influent water quality and treatment used. Finally, we estimated the amount of PFCs discharged via sludge in order to determine the potential impact to the environment according to different sludge usage practices in the two regions investigated. This manuscript provided an intra-European overview of PFC distribution in sludge. Levels and compound distribution depend on the WWTP sampled

  11. Role of dissolved humic substances surrogates on phthalate esters migration from sewage sludge.

    Zheng, Z; He, P J; Zhang, H; Shao, L M

    2008-01-01

    The facilitated transport of dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP), the priority endocrine disrupting chemicals in sludge, by dissolved humic substances (HS) was evaluated by batch extraction. The DBP, much less hydrophobic than DEHP, was inclined to migrate from sludge matrix into humic substances solutions, while the DEHP could not migrate facilitated by most humic and fulvic acids solutions, except the humic acid surrogate of high humification. This result revealed that the affinity of DEHP in sludge matrix exceeded DBP and was not susceptible by weak HS. The hydrophobic property controlled the association of phthalic acid esters on sludge residual phases. Migration rate of DBP was positively correlated to the weight-average molecular weight of HS surrogates and the aromatic extents of HA. Some functional groups in HS molecules benefited to the facilitated transport of DBP. PMID:18360003

  12. Laboratory testing in-tank sludge washing, summary letter report

    In-tank washing is being considered as a means of pretreating high-level radioactive waste sludges, such as neutralized current acid waste (NCAW) sludge. For this process, the contents of the tank will be allowed to settle, and the supernatant solution will be decanted and removed. A dilute sodium hydroxide/sodium nitrite wash solution will be added to the settled sludge and the tank contents will be mixed with a mixer pump system to facilitate washing of the sludge. After thorough mixing, the mixer pumps will be shut off and the solids will be allowed to re-settle. After settling, the supernatant solution will be withdrawn from the tank, and the wash cycle will be repeated several times with fresh wash solution. Core sample data of double shell tank 241-AZ-101 indicate that settling of NCAW solids may be very slow. A complicating factor is that strong thermal currents are expected to be generated from heat produced by radionuclides in the sludge layer at the bottom of the tank. Additionally, there are concerns that during the settling period (i.e., while mixing pumps and air-lift re-circulators are shut off), the radionuclides may heat the residual interstitial water in the sludge to the extent that violent steam discharges (steam bumping) could occur. Finally, there are concerns that during the washing steps sludge settling may be hindered as a result of the reduced ionic strength of the wash solution. To overcome the postulated reduced settling rates during the second and third washing steps, the use of flocculants is being considered. To address the above concerns and uncertainties associated with in-tank washing, PNL has conducted laboratory testing with simulant tank waste to investigate settling rates, steam bump potential, and the need for and use of flocculating agents

  13. Study of the pyrolysis of sludge and sludge/disposal filter cake mix for the production of value added products

    VELGHE, Inge; Carleer, Robert; Yperman, Jan; Schreurs, Sonja

    2013-01-01

    Slow and fast pyrolysis of sludge and sludge/disposal filter cake (FC) mix are performed to investigate the liquid and solid products for their use as value added products. The obtained slow pyrolysis liquid products separate in an oil, a water rich fraction and a valuable crystalline solid 5,5-dimethyl hydantoin. During fast pyrolysis, mainly an oil fraction is formed. Aliphatic acids and amides present in the water rich fractions can be considered as value added products and could be purifi...

  14. Androginia e intertextualidad tarótica en El milagro

    Ronald Antonio Ramírez Castellanos

    2015-01-01

    El presente estudio examina el componente mítico en la novela El milagro de Miguel de Carrión, vinculado a la temática de la androginia y su relación, desde un enfoque icónico como procedimiento del análisis semiótico, con el esoterismo tarótico, en tanto elemento de la intertextualidad de la obra. Indagaciones referidas a estos tópicos han sido poco exploradas por estudiosos de la narrativa de uno de los más importantes autores del período republicano en Cuba durante el siglo XX. De esta for...

  15. Kinetics of mesophase transformation of coal tar pitch

    Shui, H.; Feng, Y.; Shen, B.; Gao, J. [East China Institute of Metallurgy, Maanshan (China)

    1998-05-01

    A study on the kinetics of mesophase transformation of two coal tar pitches (CTP) with different primary quinoline-insoluble (QI) content is reported. It showed that the meosphase transformation of CTP studied was an autocatalytic type reaction. The rate law and rate constants for the mesophase transformation at holding temperature of 390{degree}C, 410{degree}C and 450{degree}C were determined and the rate constants of mesophase transformation follow the Arrhenius equation. Primary QI of CTP decreases the activation energy from 210.1 kJ/mol to 175.8 kJ/mol, and the pre-exponential factor from 2.12 x 10{sup 13} 1/h to 6.29 x 10{sup 10} 1/h; its influence on the rate constants is irregular. 8 refs., 3 figs., 3 tabs.

  16. Evaluation of different oxygen carriers for biomass tar reforming

    Mendiara, Teresa; Johansen, Joakim Myung; Utrilla, Rubén;

    2011-01-01

    /oxidizing cycles. Several variables affecting the reducing cycle were analyzed: temperature, time for the reduction step and H2O/C7H8 molar ratio. Ni40 and Mn40 presented interesting characteristics for CLR of biomass tar. Both showed stable reactivity to C7H8 after a few cycles. Ni40 showed a high tendency to...... carbon deposition compared to Mn40, specially at high temperatures. Carbon deposition could be controlled by decreasing the temperature and the time for the reduction step. The addition of water also reduced the amount of carbon deposited, which was completely avoided working with a H2O/C7H8 molar ratio...

  17. SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 7A QUALIFICATION

    Pareizs, J.; Billings, A.; Click, D.

    2011-07-08

    Waste Solidification Engineering (WSE) has requested that characterization and a radioactive demonstration of the next batch of sludge slurry (Sludge Batch 7a*) be completed in the Shielded Cells Facility of the Savannah River National Laboratory (SRNL) via a Technical Task Request (TTR). This characterization and demonstration, or sludge batch qualification process, is required prior to transfer of the sludge from Tank 51 to the Defense Waste Processing Facility (DWPF) feed tank (Tank 40). The current WSE practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks. Discharges of nuclear materials from H Canyon are often added to Tank 51 during sludge batch preparation. The sludge is washed and transferred to Tank 40, the current DWPF feed tank. Prior to transfer of Tank 51 to Tank 40, SRNL simulates the Tank Farm and DWPF processes with a Tank 51 sample (referred to as the qualification sample). Sludge Batch 7a (SB7a) is composed of portions of Tanks 4, 7, and 12; the Sludge Batch 6 heel in Tank 51; and a plutonium stream from H Canyon. SRNL received the Tank 51 qualification sample (sample ID HTF-51-10-125) following sludge additions to Tank 51. This report documents: (1) The washing (addition of water to dilute the sludge supernate) and concentration (decanting of supernate) of the SB7a - Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the washed Tank 51 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a non

  18. Sludge Washing And Demonstration Of The DWPF Flowsheet In The SRNL Shielded Cells For Sludge Batch 7A Qualification

    Waste Solidification Engineering (WSE) has requested that characterization and a radioactive demonstration of the next batch of sludge slurry (Sludge Batch 7a*) be completed in the Shielded Cells Facility of the Savannah River National Laboratory (SRNL) via a Technical Task Request (TTR). This characterization and demonstration, or sludge batch qualification process, is required prior to transfer of the sludge from Tank 51 to the Defense Waste Processing Facility (DWPF) feed tank (Tank 40). The current WSE practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks. Discharges of nuclear materials from H Canyon are often added to Tank 51 during sludge batch preparation. The sludge is washed and transferred to Tank 40, the current DWPF feed tank. Prior to transfer of Tank 51 to Tank 40, SRNL simulates the Tank Farm and DWPF processes with a Tank 51 sample (referred to as the qualification sample). Sludge Batch 7a (SB7a) is composed of portions of Tanks 4, 7, and 12; the Sludge Batch 6 heel in Tank 51; and a plutonium stream from H Canyon. SRNL received the Tank 51 qualification sample (sample ID HTF-51-10-125) following sludge additions to Tank 51. This report documents: (1) The washing (addition of water to dilute the sludge supernate) and concentration (decanting of supernate) of the SB7a - Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the washed Tank 51 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a non

  19. Investigation of Seasonal Heavy Metal Contents in the Activated Sludge Wastewater Treatment Plant: Case Study

    Turgay Dere

    2012-10-01

    Full Text Available In this study, composite sewage sludge samples were taken from the drying beds of the Elazig City Activated Sludge Treatment Plant in order to investigate the seasonal heavy metal concentrations in the samples. According to the results of the analysis, the acid extractable annual heavy metal concentrations of the effluent sludge coming from the drying beds were found as Fe >Zn> Mn >Cu >Cr >Ni >Pb> Co> Cd. İron concentration in the sewage sludge was found to be the highest where Cd was detected in the lowest concentration value. According to the independent t-test applied to the summer and winter pollution loads of the sewage sludge, statistical differences for the average values were observed between the groups for the iron, copper, and cadmium contents (p0.05.

  20. Enhancing toxic metal removal from acidified sludge with nitrite addition.

    Du, Fangzhou; Freguia, Stefano; Yuan, Zhiguo; Keller, Jürg; Pikaar, Ilje

    2015-05-19

    The production of sludge (biosolids) during wastewater treatment is a major issue for water utilities. A main issue limiting its beneficial reuse on agricultural lands is the presence of toxic metals. The currently used metal reduction technologies achieve insufficient removal of metals that are bound to the organic fraction of the sludge. In this study, we propose and demonstrate a novel method that involves the addition of nitrite during sludge acidification to enhance metal removal. Using waste activated sludge collected from three full-scale wastewater treatment plants, we found that acidification to pH 2.0 achieved good Zn solubilization of around 70%, but only 3-7% of Cu was being dissolved. Nitrite addition to the acidified sludge at a concentration of 20 mg NO2(-)-N/L (equals to 19.2 mg HNO2-N/L), substantially enhanced Cu removal to 45-64%, while Zn removal was also increased to over 81%. Metal distribution analysis using sequential chemical extraction revealed that the improvement of Cu and Zn removal was mainly due to the release of the organically bound metal fraction. We hypothesize that free nitrous acid (HNO2, FNA) may assist in the (partial) disruption of extracellular polymeric substances (EPS) and the subsequent release and solubilization of fixed metals. PMID:25872418

  1. Pengaruh Hydraulic Retenton Time (HRT) Dan Recycle Sludge Pada Proses Asidogenesis Limbah Cair Pabrik Kelapa Sawit (LCPKS) Menggunakan Temperatur 45 °C

    Melida, Yola

    2016-01-01

    Acidogenesis is a complex process in which microbes decompose anaerobically together organic compounds into low molecular organic acids such as Volatile Fatty Acid (VFA) consisting of acetic acid, propionic acid and butyric acid. This study aims to get the effect of variations in HRT and recycle sludge and to obtain the best sludge recycle ratio on Palm Oil Mill Effluent (POME) acidogenesis process at a temperature of 45 oC. Fermenter used is CSTR fermentor and agitation rat...

  2. Rheology of Savannah River site tank 42 and tank 51 HLW radioactive sludges

    Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site (SRS) is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. The high activity radioactive wastes stored as caustic slurries at SRS result from the neutralization of acid waste generated from production of nuclear defense materials. During storage, the wastes separate into a supernate layer and a sludge layer. In the Defense Waste Processing Facility (DWPF) at SRS, the radionuclides from the sludge and supernate will be immobilized into borosilicate glass for long term storage and eventual disposal. Before transferring the waste from a storage tank to the DWPF, a portion of the aluminum in the waste sludge will be dissolved and the sludge will be extensively washed to remove sodium. Tank 51 and Tank 42 radioactive sludges represent the first batch of HLW sludge to be processed in the DWPF. This paper presents results of rheology measurements of Tank 51 and Tank 42 at various solids concentrations. The rheologies of Tank 51 and Tank 42 radioactive slurries were measured remotely in the Shielded Cells Operations (SCO) at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco RV-12 with an M150 measuring drive unit and TI sensor system. Rheological properties of the Tank 51 and Tank 42 radioactive sludges were measured as a function of weight percent solids. The weight percent solids of Tank 42 sludge was 27, as received. Tank 51 sludge had already been washed. The weight percent solids were adjusted by dilution with water or by concentration through drying. At 12, 15, and 18 weight percent solids, the yield stresses of Tank 51 sludge were 5, 11, and 14 dynes/cm2, respectively. The apparent viscosities were 6, 10, and 12 centipoises at 300 sec-1 shear rate, respectively

  3. Assessment of alternative management techniques of tank bottom petroleum sludge in Oman

    This paper investigated several options for environmentally acceptable management techniques of tank bottom oily sludge. In particular, we tested the applicability of managing the sludge by three options: (1) as a fuel supplement; (2) in solidification; (3) as a road material. Environmental testing included determination of heavy metals concentration; toxic organics concentration and radiological properties. The assessment of tank bottom sludge as a fuel supplement included various properties such as proximate analysis, ultimate analysis and energy content. Solidified sludge mixtures and road application sludge mixtures were subjected to leaching using the toxicity characteristic leaching procedure (TCLP). Tank bottom sludge was characterized as having higher concentrations of lead, zinc, and mercury, but lower concentrations of nickel, copper and chromium in comparison with values reported in the literature. Natural occurring radioactive minerals (NORM) activity values obtained on different sludge samples were very low or negligible compared to a NORM standard value of 100 Bq/g. The fuel assessment results indicate that the heating values, the carbon content and the ash content of the sludge samples are comparable with bituminous coal, sewage sludge, meat and bone meal and petroleum coke/coal mixture, but lower than those in car tyres and petroleum coke. The nitrogen content is lower than those fuels mentioned above, while the sulfur content seems comparable with bituminous coal, petroleum coke and a petroleum coke/coal mixture. The apparent lack of leachability of metals from solidification and road material sludge applications suggests that toxic metals and organics introduced to these applications are not readily attacked by weak acid solutions and would not be expected to migrate or dissolved into the water. Thus, in-terms of trace metals and organics, the suggested sludge applications would not be considered hazardous as defined by the TCLP leaching procedure

  4. Canada's toxic tar sands : the most destructive project on earth

    Hatch, C.; Price, M. [Environmental Defence, Toronto, ON (Canada)

    2008-02-15

    This document addressed the environmental problems associated with tar sands development in Alberta, with particular reference to toxicity problems associated with global warming and the impending destruction of the boreal forest. The authors cautioned that the tar sand projects are highly destructive, leaving downstream toxics equivalent to that of a massive slow motion oil spill that has the potential to poison people. Negligent oversights by the government regarding the impact of tar sands development were also discussed, with reference to toxics on site; toxics downwind; and toxics down the pipe. The report also provided information on the future of tar sands development and global warming in Canada. It included a discussion of reverse alchemy; Canada's failed climate politics; a tar sands tax; and taking responsibility. Last, the report addressed toxic enforcement, including the Fisheries Act; Canadian Environmental Protection Act; Canadian Environmental Assessment Act; and Alberta law. It was concluded that while it is a stretch to believe the tar sands can truly be sustainable, there is a great deal that can be done to clean it up. The authors recommended that new tar sands approvals should wait until certain reform elements are implemented, such as passing a real carbon cap; using dry tailings; requiring wildlife offsets; cleaning up refineries and upgraders; ensuring Aboriginal control and benefit; and having regulation and independent monitoring. 104 refs., 6 figs.

  5. Opening of the TAR hairpin in the HIV-1 genome causes aberrant RNA dimerization and packaging

    Das Atze T

    2012-07-01

    Full Text Available Abstract Background The TAR hairpin is present at both the 5′ and 3′ end of the HIV-1 RNA genome. The 5′ element binds the viral Tat protein and is essential for Tat-mediated activation of transcription. We recently observed that complete TAR deletion is allowed in the context of an HIV-1 variant that does not depend on this Tat-TAR axis for transcription. Mutations that open the 5′ stem-loop structure did however affect the leader RNA conformation and resulted in a severe replication defect. In this study, we set out to analyze which step of the HIV-1 replication cycle is affected by this conformational change of the leader RNA. Results We demonstrate that opening the 5′ TAR structure through a deletion in either side of the stem region caused aberrant dimerization and reduced packaging of the unspliced viral RNA genome. In contrast, truncation of the TAR hairpin through deletions in both sides of the stem did not affect RNA dimer formation and packaging. Conclusions These results demonstrate that, although the TAR hairpin is not essential for RNA dimerization and packaging, mutations in TAR can significantly affect these processes through misfolding of the relevant RNA signals.

  6. Skin disease after occupational dermal exposure to coal tar: a review of the scientific literature.

    Moustafa, Giannis-Aimant; Xanthopoulou, Eleni; Riza, Elena; Linos, Athena

    2015-08-01

    For about a century, coal tar has been used in industry and has been applied in the therapeutic management of several skin diseases. However, in the last decades the benefits of coal tar exploitation for humans could not outweigh its harmful effects on health. The aim of this study is to present the main adverse effects of coal tar on skin, with the emphasis on occupational exposure. The scientific literature indicates that dermal exposure to coal tar and coal tar pitches can be the cause of phototoxic reactions, irritation and burn, allergic dermatitis, folliculitis, occupational acne, atrophy of the epidermis, and hyperpigmentation. Moreover coal tar has been implicated in tumorigenesis, a relationship shown in numerous studies but not confirmed yet as the mechanism has not been fully clarified. A common finding in most studies is that exposure over a long period is the main risk factor for malignancy development, even in low exposure levels. Additional prospective, well-designed studies need to be performed to confirm the validity of the carcinogenic, mutagenic, and cytotoxic potential of coal tar on skin. PMID:26183242

  7. Catalytic Tar Reduction for Assistance in Thermal Conversion of Space Waste for Energy Production

    Caraccio, Anne Joan; Devor, Robert William; Hintze, Paul E.; Muscatello, Anthony C.; Nur, Mononita

    2014-01-01

    The Trash to Gas (TtG) project investigates technologies for converting waste generated during spaceflight into various resources. One of these technologies was gasification, which employed a downdraft reactor designed and manufactured at NASA's Kennedy Space Center (KSC) for the conversion of simulated space trash to carbon dioxide. The carbon dioxide would then be converted to methane for propulsion and water for life support systems. A minor byproduct of gasification includes large hydrocarbons, also known as tars. Tars are unwanted byproducts that add contamination to the product stream, clog the reactor and cause complications in analysis instrumentation. The objective of this research was to perform reduction studies of a mock tar using select catalysts and choose the most effective for primary treatment within the KSC downdraft gasification reactor. Because the KSC reactor is operated at temperatures below typical gasification reactors, this study evaluates catalyst performance below recommended catalytic operating temperatures. The tar reduction experimentation was observed by passing a model tar vapor stream over the catalysts at similar conditions to that of the KSC reactor. Reduction in tar was determined using gas chromatography. Tar reduction efficiency and catalyst performances were evaluated at different temperatures.

  8. Geochemical Characteristics and Origin of Tar Mats from the Yaha Field in Tarim Basin,China

    张敏; 张俊; 等

    1999-01-01

    Tar mats were firstly discovered and determined accurately in terrestrial oil and gas reservoirs associated with Lower Tertiary sandstone reservoirs in the Yaha field of the Tarim Basin,China,by thin-layer chromatography-flame ionization detector(TLC-FID)and Rock-Eval analysis.The relative content of asphaltene in gross composition of tar mat extracts accounts for more than 30%,that in the corresponding oil leg less than 20%.In the geochemical description profile of oil gas reservoirs,drastic changes in asphaltene contents between tar mats and oil legs could be discovered.This in an important marker to determine tar mats.Distribution characteristics of saturated and aromaic hydrocarbons from reservoir core extracts and crude oils in the Yaha oil and gas reservoirs in the Tarim Basin are described systematically in this paper,and the results show there are similarities among n-alkane distribution characteristics,biomarker distribution characteristics and their combined characteristics of saturated hydrocarbons,and the geochemical characteristics of aromatic hydrocarbons for tar mats.oil leg,asphaltic sand and crude oil.These characteristics suggest the hydrocarbons in these samples were originated from the common source rocks.However,the geochemical characteristics of tar mats reveales that the mechanism of formation of tar mats is the precipitation of asphaltene from crude oils in petroleum reservoirs caused by increased dissolved gas in oil legs(gas injection).

  9. Sewage sludge drying and combustion

    Salgado, Mario Alejandro Heredia

    2014-01-01

    A brief review of the paper pulp production process in order to understand the origin of the sewage sludge was performed. Then a general revision of the current treatment options for this type of waste was addressed. The thermal treatment by combustion was focused and a review of the state of the art of this process was performed. The high moisture content of sludge was identified as a major concern. Thus a revision of the state of the art regarding thermal drying of sewage sludge was perform...

  10. Carbazole is a naturally occurring inhibitor of angiogenesis and inflammation isolated from antipsoriatic coal tar

    Jack L. Arbiser; Baskaran Govindarajan; Traci E. Battle; Rebecca Lynch; David A. Frank; Masuko Ushio-Fukai; Betsy N. Perry; David F. Stern; G. Tim Bowden; Anquan Liu; Eva Klein; Pawel J. Kolodziejski; N. Tony Eissa; Chowdhury F. Hossain; Dale G. Nagle [Emory University School of Medicine, Atlanta, GA (United States). Department of Dermatology

    2006-06-15

    Coal tar is one of the oldest and an effective treatment for psoriasis. Coal tar has been directly applied to the skin, or used in combination with UV light as part of the Goeckerman treatment. The use of coal tar has caused long-term remissions in psoriasis, but has fallen out of favor because the treatment requires hospitalization and coal tar is poorly acceptable aesthetically to patients. Thus, determining the active antipsoriatic component of coal tar is of considerable therapeutic interest. We fractionated coal tar into its components, and tested them using the SVR angiogenesis inhibitor assay. Treatment of SVR endothelial cells with coal tar fractions resulted in the isolation of a single fraction with antiangiogenic activity. The active antiangiogenic compound in coal tar is carbazole. In addition to antiangiogenic activity, carbazole inhibited the production of inflammatory IL-15 by human mononuclear cells. IL-15 is elevated in psoriasis and is thought to contribute to psoriatic inflammation. Carbazole treatment also reduced activity of inducible nitric oxide synthase (iNOS), which is proinflammatory and elevated in psoriasis. The effect of carbazole on upstream pathways in human psoriasis was determined, and carbazole was shown to inhibit signal transducer and activator of transcription (stat)3-mediated transcription, which has been shown to be relevant in human psoriasis. IL-15, iNOS, and stat3 activation require the activation of the small GTPase rac for optimal activity. Carbazole was found to inhibit rac activation as a mechanism for its inhibition of downstream inflammatory and angiogenic pathways. Given its antiangiogenic and anti-inflammatory activities, carbazole is likely a major component of the antipsoriatic activity of coal tar. Carbazole and derivatives may be useful in the therapy of human psoriasis.

  11. Physicochemical changes effected in activated sludge by the earthworm Eisenia foetida. [Concentration of heavy metals during sludge catabolism

    Hartenstein, R. (State Univ. of New York, Syracuse); Hartenstein, F.

    1981-09-01

    Measurements were made of some physicochemical changes effected in activated sludge by the earthworm Eisenia foetida following conversion of the sludge into wormcasts. Mineralization was accelerated 1.3-fold and 2% of the minerals were assimilated. The rate at which heavy metals were concentrated during sludge catabolism was also accelerated. Castings stabilized within 2 weeks, as indexed by respirometry. Nucleic acids, which can be used as an index of microbial biomass, were present at a greater concentration in the wormcasts than in the sludge, while the phenolic content, which may potentially serve as an index of humification, was less concentrated. Other changes included a reduction in pH and an increase in oxidation-reduction potential and cation exchange capacity. The major general effect of E. foetida on the physicochemical properties of activated sludge is to convert a material which has a relatively small surface/volume ratio into numerous particles with an overall large S/V ratio, thus accelerating decomposition, mineralization, drying, and preclusion of malodor.

  12. Characterisation of dense non-aqueous phase liquids of coal tar using comprehensive two-dimensional gas chromatography coupled with time of flight mass spectrometry.

    Gauchotte-Lindsay, Caroline; McGregor, Laura; Richards, Phil; Kerr, Stephanie; Glenn, Aliyssa; Thomas, Russell; Kalin, Robert

    2013-04-01

    Comprehensive two-dimensional gas chromatography (GCxGC) is a recently developed analytical technique in which two capillary columns with different stationary phases are placed in series enabling planar resolution of the analytes. The resolution power of GCxGC is one order of magnitude higher than that of one dimension gas chromatography. Because of its high resolution capacity, the use of GCxGC for complex environmental samples such as crude oils, petroleum derivatives and polychlorinated biphenyls mixtures has rapidly grown in recent years. We developed a one-step method for the forensic analysis of coal tar dense non-aqueous phase liquids (DNAPLs) from former manufactured gas plant (FMGP) sites. Coal tar is the by-product of the gasification of coal for heating and lighting and it is composed of thousands of organic and inorganic compounds. Before the boom of natural gases and oils, most towns and cities had one or several manufactured gas plants that have, in many cases, left a devastating environmental print due to coal tar contamination. The fate of coal tar DNAPLs, which can persist in the environment for more than a hundred years, is therefore of crucial interest. The presented analytical method consists of a unique clean-up/ extraction stage by pressurized liquid extraction and a single analysis of its organic chemical composition using GCxGC coupled with time of flight mass spectrometry (TOFMS). The chemical fingerprinting is further improved by derivatisation by N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) of the tar compounds containing -OH functions such as alcohols and carboxylic acids. We present here how, using the logical order of elution in GCxGC-TOFMS system, 1) the identification of never before observed -OH containing compounds is possible and 2) the isomeric selectivity of an oxidation reaction on a DNAPL sample can be revealed. Using samples collected at various FMGP sites, we demonstrate how this GCxGC method enables the simultaneous

  13. "Recovery of Iron Coagulants From Tehran Water-Treatment-Plant Sludge for Reusing in Textile Wastewater Treatment"

    F Vaezi

    2001-09-01

    Full Text Available Most of the water treatment plants in Iran discharge their sludge to the environment whithout consideration of possible side effects. Since this kind of sludge is generally considered pollutant, the sludge treatment of water industry seems to be an essential task. Obviously theweight and volume of solids produced during the coagulation process are much more than other wastes of water treatment operations, and their treatment is much more difficult as well. Besides, this sludge contains metal hydroxide so disposing of it would waste considerable amounts of valuable metal salts. To face the mentioned problems, reclamation of coagulatns from waste sludges for reuse has been investigated in this research. Among different chemicals used in the experiments of recovery, sulfuric-acid showed better results from both practical and cost viewpoints. Three important phenomena were observed by sludge acidificantion: dissolution of metal hydroxide, reduction of sludge volume and finally faster settleability and dryness of remainder sludge. The salt recovered by sulfuric acid from the sludges of Tehran Water-Treatment Plant was ferric sulfate which showed good results in the treatment of two different types of wastewaters from textile industry.

  14. Influence of ferrous ions on extracellular polymeric substances content and sludge dewaterability during bioleaching.

    Wong, Jonathan W C; Zhou, Jun; Kurade, Mayur B; Murugesan, Kumarasamy

    2015-03-01

    Pretreatment of activated sludge with sulfuric acid and bioleaching using Acidithiobacillus ferrooxidans along with addition of Fe(2+) on sludge dewaterability was investigated. The sludge dewatering efficiency in terms of capillary suction time (CST) and specific resistant to filtration (SRF) was increased with a decrease in sludge pH. A pH of 2.67 was found to be optimum for dewatering, at which 81% and 63% reduction of CST and SRF were achieved, respectively. The dewaterability of sludge was enhanced after the addition of Fe(2+) and A. ferrooxidans. Ideal concentration of Fe(2+) was 2 g/L for sludge dewaterability, which showed 96% and 88% reduction in CST and SRF, respectively. In the control sludge, maximum part of the biopolymeric macromolecules was contributing by the tightly bound extracellular polymeric substances (TB-EPS). At optimum Fe(2+) concentration, total EPS was reduced by 73%, enhancing sludge dewaterability. Bioleaching conducted by A. ferrooxidans could solubilized 88% Cu and 99% Zn within 120 h. PMID:25528607

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

    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)

  16. Assessment of the ability of sludge to degrade PCP under anaerobic conditions

    R. M. L. Bolaños

    2005-12-01

    Full Text Available The capacity of sludge from different sources to degrade pentachlorophenol (PCP was evaluated. Three 2.5 liter reactors (R1, R2, and R3 were inoculated with different anaerobic sludges, semi continuously fed and maintained in orbital motion at 30±1°C. R1 was inoculated with aerobic sludge and river sediment collected downstream from a pulp and paper plant. R2 received sludge from an anaerobic reactor treating effluents from a paper recycling plant and R3 received anaerobic sludge from a biodigestor treating industrial and domestic effluents. The sludges were first acclimatized to a culture medium generally recommended for organochloride anaerobic degradation studies. The reactors were then subjected to increasing concentrations of PCP from 0.05 to 10.0 mg.l-1. PCP degradation and metabolite formation were monitored using gas chromatography, and the effects of PCP on the anaerobic process were verified by monitoring pH, volatile fatty acids, alkalinity, total suspended solids, and chemical oxygen demand. It was found that PCP did not affect reactor performance. All the sludges displayed the best PCP degradation capacity at a concentration of 0.2 mg.l-1, producing fewer chlorinated metabolites than when higher PCP concentrations were applied. R1 consistently produced fewer chlorinated metabolites, confirming the hypothesis that pre exposure to chlorinated compounds improves the sludge's capacity to degrade PCP.

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

    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

  18. Effects of thermally pretreated temperature on bio-hydrogen production from sewage sludge

    XIAO Ben-yi; LIU Jun-xin

    2006-01-01

    Hydrogen can be obtained by anaerobic fermentation of sewage sludge. Therefore, in this paper the effects of thermally pretreated temperatures on hydrogen production from sewage sludge were investigated under different pre-treatment conditions. In the thermal pretreatment, some microbial matters of sludge were converted into soluble matters from insoluble ones. As a result, the suspended solid(SS) and volatile suspended solid(VSS) of sludge decreased and the concentration of soluble COD(SCOD) increased,including soluble carbohydrates and proteins. The experimental results showed that all of those pretreated sludge could produce hydrogen by anaerobic fermentation and the hydrogen yields under the temperatures of 121 ℃ and 50℃ were 12.23 ml/g VS(most)and 1.17 ml/g VS (least), respectively. It illuminated that the hydrogen yield of sludge was affected by the thermally pretreated temperatures. Additionally, the endurance of high hydrogen yield depended on the translation of microbial matters and inhibition of methanogens in the sludge. The temperatures of 100℃ and 121℃ (treated time, 30 min) could kill or inhibit completely the methanogens while the others could not. To produce hydrogen and save energy, 100℃ was chosen as the optimal temperature for thermal pretreatment. The composition changes in liquid phase in the fermentation process were also discussed. The SCOD of sludge increased, which was affected by the pretreatment temperature. The production of volatile fatty acids in the anaerobic fermentation increased with the pretreatment temperature.

  19. Sludge pretreatment chemistry evaluation: Enhanced sludge washing separation factors

    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

  20. Characterization of the replication and stability regions of Agrobacterium tumefaciens plasmid pTAR.

    Gallie, D R; Zaitlin, D; Perry, K L; Kado, C I

    1984-01-01

    A 5.4-kilobase region containing the origin of replication and stability maintenance of the 44-kilobase Agrobacterium tumefaciens plasmid pTAR has been mapped and characterized. Within this region is a 1.3-kilobase segment that is capable of directing autonomous replication. The remaining segment contains the stability locus for maintenance of pTAR during nonselective growth. Approximately 35% of pTAR shares sequence homology with pAg119, a 44-kilobase cryptic plasmid in grapevine strain 1D11...

  1. Simulation of Trajectories of Tar Ball Transport to the Goa Coast

    Suneel, V.; Vethamony, P.; VinodKumar, K.; Babu, M.T.; Prasad, V.S.R.

    were predicted for open boundaries from Global Tidal Model (inbuilt in MIKE ZERO). 2.2.3. Tracking of tar ball transport Tar ball transport is tracked using Particle Analysis (PA) module of MIKE 21. PA module is based on Lagrangian Random walk... act as nuclei around the oil slicks/emulsions and form the tar ball (Heaton et al, 1980). The cyclonic eddy produces the convergence in the ocean while the divergence is due to an anticyclonic eddy. According to the Sand theory, when oil encounters...

  2. A comparison of thermal conversion process for several coal tar pitches

    Feng, Y.; Shui, H.; Yuan, X. [East China Metallurgical Institute, Ma`anshan (China)

    1995-03-01

    The property and constituents of coal tar pitch are of great importance to the production of raw material for needle coke. Structural constituents of five coal tar pitches were determined using {sup 1}H-NMR. Besides, thermal conversion process of these pitches in which primary quinoline in soluble fraction was removed by centrifugal separation method was also investigated. The experimental results show Baogang (I) and Meishan coal tar pitches meet the requirements of raw material for needle coke. The thermal conversion data was correlated with structural parameters. 6 refs.,1 fig., 1 tab.

  3. A role for nuclear energy in the recovery of oil from the tar sands of Alberta

    Techniques of oil recovery from the tar sands and the energy requirements of this operation are described. Fossil fuels, and CANDU reactors are examined as competitive sources of energy for the tar sands plants. The CANDU-OCR reactor appears to have the necessary flexibility to fit into many of the possible methods of recovering oil from the tar sands. Cost comparisons of fossil and nuclear sources show that, for the supply of process steam, the nuclear source is competitive under the criteria of debt financing or low discount rates on capital, continued escalation, and long plant capital write-off period. (author)

  4. Municipal sewage sludge to biodiesel by simultaneous extraction and conversion of lipids

    Highlights: • Efficient production of biodiesel from primary and secondary sewage sludge. • Zr-SBA-15 converts more than 90% of the saponifiable oil fraction into FAME. • High water and impurities tolerance of the Zr-SBA-15 catalyst. - Abstract: Two different approaches have been investigated for the production of biodiesel from glycerides and free fatty acids (FFAs) extracted from sewage sludge. The first one is a two-step process consisting of organic solvent extraction followed by acid-catalyzed esterification/transesterification of the isolated oil fraction. The second one is a one-step direct transformation consisting of the simultaneous extraction and conversion of the lipid fraction contained in the sewage sludge. In both alternatives, a heterogeneous acid Zr-SBA-15 catalyst has been used. In the two-step extraction–reaction process, conversion close to 90% of the saponifiable fraction (including FFAs and glycerides) were achieved. Remarkably, the catalyst provided such high conversion in the presence of high amounts of unsaponifiable matter. Furthermore, the catalyst kept its activity in successive catalytic runs in presence of this low-quality lipid fraction. In the one-step direct conversion of the dried sludge, the overall weight FAME yield, based on the initial mass of dried sewage sludge, was around 15.5 wt% for primary and 10.0 wt% for secondary sludge. In contrast, this FAME yield was lower than 6 wt% for two-step process when processing primary sludge (being negligible for the secondary sludge). Finally, the results of this work proof the high potential of Zr-SBA-15 as catalyst for the production of biodiesel from a low quality oleaginous feedstock such as municipal sewage sludge

  5. Microbiological and biochemical properties of an agricultural Mexican soil amended with sewage sludge

    Renato Armenta

    2012-11-01

    Full Text Available The application of sewage sludge is a concern because it may affect the quality of organic matter and microbiological and biochemical soil properties. The effects of surface application of sewage sludge to an agricultural soil (at 18 and 36 t ha-1 dry basis were assessed in one maize (Zea mays L. growing season. The study evaluated microbial biomass, basal respiration and selected enzymatic activities (catalase, urease, acid and alkaline phosphatase, and β-glucosidase 230 days after sewage sludge application and infrared spectroscopy was used to assess the quality of dissolved organic matter and humic acids. Sewage sludge applications increased the band intensity assigned to polysaccharides, carboxylic acids, amides and lignin groups in the soil. The organic matter from the sewage sludge had a significant influence on the soil microbial biomass; nevertheless, at the end of the experiment the equilibrium of the soil microbial biomass (defined as microbial metabolic quotient, qCO2 was recovered. Soil urease, acid and alkaline phosphatase activity were strongly influenced by sewage sludge applications.

  6. 酸碱性调节对混合污泥氮磷释放及回收的影响%Impact of acid-alkali adjustment on release and recovery of nitrogen and phosphorus from mixed sludge

    杨和义

    2011-01-01

    在pH值分别为3.0和10.0的条件下,以不调节pH值作对比,研究了10~15℃下混合污泥水解酸化过程中NH3-N和PO4--p的释放规律,并对鸟粪石法回收氮磷做了可行性分析.结果表明,强碱能够促进NH3-N大量释放,第10天时其释放量接近最大16.80 mg/g[TS],pH值为3.0可抑制氨氮的释放.与NH3 -N相反,PO34-P的释放量大小为pH值为3.0>空白>pH值为10.0,酸性条件反应12d时其释放量接近最大,为8.52 mg/g[TS].宜选用酸性条件反应12d作为鸟粪石回收的最佳条件,但因Ca2+对鸟粪石形成的严重干扰,需要采取合理的措施将其去除后才能有利于鸟粪石的形成.%Taking the condition under uncontrolled pH as the contrast, the rules of NH3-N and PO43 -P release during the hydrolysis acidification of mixed sludge at 10 - 15 ℃ with the pH controlled at 3.0 and 10.0 were studied respectively, and then, the feasibility of using struvite precipitation method to recover nitrogen and phosphorus was evaluated. The results showed that, strong alkali could facilitate the release of NH3-N; the release amount was close to the maximum: 16.80 mg/g[TS] on the 10th day, and the process was inhibited at pH 3.0. Contrary to the release of NH3-N, the release amount of PO43--P under different pH conditions showed a descending order as follows: at pH 3.0 > blank test > at pH 10.0, the release amount reached the maximum: 8.52 mg/g[TS] after 12 days of reaction under acidic condition. It was advisable to consider 12 days of reaction under acidic condition as the optimal operating condition for the struvite precipitation. However, due to the serious interference of Ca2+ to the struvite formation, rational measures to removing Ca2+ should be taken first so as to benefit the struvite formantion.

  7. Radiation processing of sewage sludge

    The sludge resulting from municipal wastewater treatment usually is in the form of a liquid or semisolid liquid that typically contains 0.25-12% solids by weight, depending on the operations and processes used. Of the components removed in wastewater treatment, sludge is by far the greatest in volume, and the problems associated with its processing and disposal are complex because: - It is composed of the substances responsible for the offensive character of untreated wastewater; - The portion of sludge produced from biological treatment and requiring disposal is composed of the organic matter contained in the wastewater, but in a form that can decompose and become offensive; - Only a small portion of the sludge is solid matter

  8. Aluminum removal from washed sludge

    Purpose of this project is to reduce the volume of storage tank sludge to be treated by removing the Al and other nonradioactive components. In initial sludge surrogate studies, Al, Cr, and Zn showed the highest solubility in NaOH solutions; Ce and Zr were the least soluble of the elements tested. Removal of Fe and Bi approached 2%, the rest of the elements studied showed <1% removal. Amount of Al removed increased as the NaOH conc. increased from 0.1 to 6 M. Sequential washing of the sludge surrogate with 3 M NaOH removed 84% of the Al, 39% of the Cr, and 65% of the Zn. Surrogate sludges containing U and Th were also studied

  9. Steam generator sludge removal apparatus

    The present invention relates to equipment for cleaning steam generators and in particular to a high pressure fluid lance for cleaning sludge off the steam generator tubes away from an open tube lane. 6 figs

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

    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

  11. Irradiation of municipal sludge for agricultural use

    Ahlstrom, Scott B.

    Research has demonstrated that irradiation is an effective means for reducing pathogens in sewage sludge to levels where sludge reuse in public areas meets criteria for protection of the public health. Complementary research has demonstrated the value of the irradiated sludge in both agronomic and animal science applications. The benefits of sludge application to cropland are well documented. The irradiation process does not increase the extractability and plant uptake of a broad range of nutrients and heavy metals from sludge-amended soils. However, it does eliminate the hazards associated with pathogen contamination when applying sludge to agricultural land. Irradiated sludge has also been evaluated as a supplemental foodstuff for cattle and sheep. The data indicate that products derived from raw sewage may have a substantial nutritive value for ruminant animals. Irradiation of sewage sludge is a practical means of sludge disinfection. Where a highly disinfected sludge is required, it should be considered as a viable sludge management alternative. Evaluation of sludge irradiation technology and its associated costs must be done with consideration of other sludge treatment processes to develop an acceptable sludge management system.

  12. Hydrothermal carbonization of industrial mixed sludge from a pulp and paper mill

    Mäkelä, Mikko; Benavente Domenech, Verónica; Fullana Font, Andrés

    2015-01-01

    Mixed sludge from a pulp and paper mill was hydrothermally carbonized at 180–260 °C for 0.5–5 h with the use of HCl or NaOH for determining the effect of acid and base additions during sludge carbonization. Based on the results carbonization was mainly governed by dehydration, depolymerization and decarboxylation of sludge components. Additive type had a statistically significant effect on hydrochar carbon content and carbon and energy yield, of which especially energy yield increased through...

  13. Enhanced sludge washing evaluation plan

    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

  14. Comparative Study of the Modification of Coal Tar Pitch for Higher Carbonization Yield and Better Properties

    张文娟; 李铁虎; 卢萌; 侯翠岭

    2013-01-01

    Parent coal tar pitch (CTP) was modified with boric acid (BA), cinnamaldehyde (CMA) and the mixture of BA and CMA, respectively. The parent CTP and three modified CTPs were characterized by elemental analysis, thermogravimetric analysis, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy. The four samples were carbonized at different temperatures and resultant carbonized products were characterized by FT-IR spectroscopy, X-ray diffraction and polarized-light microscopy. The results show that the morphologies and carbonization behaviors of the parent CTP and modified CTPs are quite different. The carbonization yield of the CTP modified with the mixture of BA and CMA is higher than that of CTP modified with BA or CMA only. In addition, the modification of CTP with 7 g of BA and 10 ml of CMA results in an increase in carbonization yield by 5.64%. During the pyrolysis of modified CTPs, the dehydration of BA or the distillation of CMA occurs at the tem-perature lower than 300 °C, and methyl and methylene groups of the modified CTPs disappear gradually as tem-perature rises. Furthermore, the modification of CTP by the mixture of BA and CMA results in more intensive mesophase spheres than other modified CTPs, and the modified CTP is easier to be carbonized to form graphitic carbon.

  15. Effects of Sludge-amendment on Mineralization of Pyrene and Microorganisms in Sludge and Soil

    Klinge, C; Gejlsbjerg, B; Ekelund, Flemming;

    2001-01-01

    Hydrophobic contaminants sorb to sludge in wastewater treatment plants and enter the soil environment when the sludge is applied to agricultural fields. The mineralization of pyrene was examined in soil, in sludge mixed homogeneously into soil, and in sludge-soil systems containing a lump of sludge....... Sludge-amendment enhanced the mineralization of pyrene in the soil compared to soil without sludge, and the most extensive mineralization was observed when the sludge was kept in a lump. The number of protozoa, heterotrophic bacteria and pyrene-mineralizing bacteria was much higher in the sludge compared...... to the soil. The amendment of sludge did not affect the number of protozoa and bacteria in the surrounding soil, which indicated that organic contaminants in the sludge had a little effect on the number of protozoa and bacteria in the surrounding soil...

  16. Tar removal from biosyngas in the biomass gasification process. (Liquid + liquid) equilibrium {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)}

    Highlights: ► (Liquid + liquid) equilibria at atmospheric pressure. ► Solubility of benzene (or toluene or phenol) in paraxylene at (303 to 343) K. ► Solubility of benzene (or toluene or phenol) in methyl palmitate or methyl hexadecanoate at (303 to 343) K. ► Correlation of LLE using NRTL model. - Abstract: Tar is generated in the process by the condensation of the gas resulting from biomass gasification. The objective of this work is a contribution to the database on thermodynamic quantity which will be useful at the operation of tar removal from aqueous medium. With this aim, (liquid + liquid) equilibrium of {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)} was studied at temperatures (303.2, 323.2, and 343.2) K. The data obtained were correlated with the non-random two-liquid (NRTL) model.

  17. Light absorption properties of laboratory generated tar ball particles

    A. Hoffer

    2015-06-01

    Full Text Available Tar balls (TBs are a specific particle type which is abundant in the global troposphere, in particular in biomass smoke plumes. These particles belong to the family of atmospheric brown carbon (BrC which can absorb light in the visible range of the solar spectrum. Albeit TBs are typically present as individual particles in biomass smoke plumes, their absorption properties have been only indirectly inferred from field observations or calculations based on their electron energy-loss spectra. This is because in biomass smoke TBs coexist with various other particle types (e.g. organic particles with inorganic inclusions and soot, the latter is emitted mainly during flaming conditions from which they cannot be physically separated; thus, a direct experimental determination of their absorption properties is not feasible. Very recently we have demonstrated that TBs can be generated in the laboratory from droplets of wood tar that resemble atmospheric TBs in all of their observed properties. As a follow-up study we have installed on-line instruments to our laboratory set-up generating pure TB particles to measure the absorption and scattering, as well as size distribution of the particles. In addition, samples were collected for transmission electron microscopy (TEM and total carbon (TC analysis. The effects of experimental parameters were also studied. The mass absorption coefficients of the laboratory generated TBs were found to be in the range of 0.8–3.0 m2 g−1 at 550 nm, with absorption Ångström exponents (AAE between 2.7 and 3.4 (average 2.9 in the wavelength range 467–652 nm. The refractive index of TBs as derived from Mie calculations was about 1.84–0.21i at 550 nm. In the brown carbon continuum these values fall closer to those of soot than to other light-absorbing species such as humic-like substances (HULIS. Considering the abundance of TBs in biomass smoke and the global magnitude of biomass burning emissions, these findings may

  18. Light absorption properties of laboratory generated tar ball particles

    Hoffer, A.; Tóth, A.; Nyirő-Kósa, I.; Pósfai, M.; Gelencsér, A.

    2015-06-01

    Tar balls (TBs) are a specific particle type which is abundant in the global troposphere, in particular in biomass smoke plumes. These particles belong to the family of atmospheric brown carbon (BrC) which can absorb light in the visible range of the solar spectrum. Albeit TBs are typically present as individual particles in biomass smoke plumes, their absorption properties have been only indirectly inferred from field observations or calculations based on their electron energy-loss spectra. This is because in biomass smoke TBs coexist with various other particle types (e.g. organic particles with inorganic inclusions and soot, the latter is emitted mainly during flaming conditions) from which they cannot be physically separated; thus, a direct experimental determination of their absorption properties is not feasible. Very recently we have demonstrated that TBs can be generated in the laboratory from droplets of wood tar that resemble atmospheric TBs in all of their observed properties. As a follow-up study we have installed on-line instruments to our laboratory set-up generating pure TB particles to measure the absorption and scattering, as well as size distribution of the particles. In addition, samples were collected for transmission electron microscopy (TEM) and total carbon (TC) analysis. The effects of experimental parameters were also studied. The mass absorption coefficients of the laboratory generated TBs were found to be in the range of 0.8-3.0 m2 g-1 at 550 nm, with absorption Ångström exponents (AAE) between 2.7 and 3.4 (average 2.9) in the wavelength range 467-652 nm. The refractive index of TBs as derived from Mie calculations was about 1.84-0.21i at 550 nm. In the brown carbon continuum these values fall closer to those of soot than to other light-absorbing species such as humic-like substances (HULIS). Considering the abundance of TBs in biomass smoke and the global magnitude of biomass burning emissions, these findings may have substantial

  19. Light absorption properties of laboratory-generated tar ball particles

    Hoffer, A.; Tóth, A.; Nyirő-Kósa, I.; Pósfai, M.; Gelencsér, A.

    2016-01-01

    Tar balls (TBs) are a specific particle type that is abundant in the global troposphere, in particular in biomass smoke plumes. These particles belong to the family of atmospheric brown carbon (BrC), which can absorb light in the visible range of the solar spectrum. Albeit TBs are typically present as individual particles in biomass smoke plumes, their absorption properties have been only indirectly inferred from field observations or calculations based on their electron energy-loss spectra. This is because in biomass smoke TBs coexist with various other particle types (e.g., organic particles with inorganic inclusions and soot, the latter emitted mainly during flaming conditions) from which they cannot be physically separated; thus, a direct experimental determination of their absorption properties is not feasible. Very recently we have demonstrated that TBs can be generated in the laboratory from droplets of wood tar that resemble atmospheric TBs in all of their observed properties. As a follow-up study, we have installed on-line instruments to our laboratory set-up, which generate pure TB particles to measure the absorption and scattering, as well as the size distribution of the particles. In addition, samples were collected for transmission electron microscopy (TEM) and total carbon (TC) analysis. The effects of experimental parameters were also studied. The mass absorption coefficients of the laboratory-generated TBs were found to be in the range of 0.8-3.0 m2 g-1 at 550 nm, with absorption Ångström exponents (AAE) between 2.7 and 3.4 (average 2.9) in the wavelength range 467-652 nm. The refractive index of TBs as derived from Mie calculations was about 1.84 - 0.21i at 550 nm. In the brown carbon continuum, these values fall closer to those of soot than to other light-absorbing species such as humic-like substances (HULIS). Considering the abundance of TBs in biomass smoke and the global magnitude of biomass burning emissions, these findings may have

  20. Secondary reactions of tar during thermochemical biomass conversion[Dissertation 14341

    Morf, P.O.

    2001-07-01

    This dissertation submitted to the Swiss Federal Institute of Technology in Zurich presents and discusses the results obtained during the examination of the processes involved in the formation and conversion of tar in biomass gasification plant. Details are given on the laboratory reactor system used to provide separated tar production and conversion for the purposes of the experiments carried out. The results of analyses made of the tar and the gaseous products obtained after its conversion at various temperatures are presented. The development of kinetic models using the results of the experiments that were carried out is described. The results of the experiments and modelling are compared with the corresponding results obtained using a full-scale down-draft, fixed-bed gasifier. The author is of the opinion that the reaction conditions found in full-scale gasifiers can be well simulated using heterogeneous tar conversion experiments using the lab reactor system.

  1. Thatcheri tütar avalikustas Raudse Leedi nõdrameelsuse / Sandra Maasalu

    Maasalu, Sandra

    2008-01-01

    Ilmunud ka: Postimees : na russkom jazõke 26. aug. 2008, lk. 9. Suurbritannia endise peaministri Margaret Thatcheri tütar Carol Thatcher kirjutab peatselt ilmuvas mälestusteraamatus oma ema dementsusest

  2. Coal tar, material used in soil improvement for use in road engineering

    Ochoa Díaz, R.; Montañez, A.; Cuentas, J.

    2016-02-01

    Coal tar is a by-product of coal distillation in the absence of oxygen to obtain metallurgical coke; its colour varies from dark coffee to black, slightly viscous and its density is greater than that of water. Taking into account the previous characteristics, this document presents a study of the feasibility of using coal tar for the improvement of physical properties, mechanics and dynamics of materials used in road engineering. In this way, the origin, characteristics, and properties of tar are first described. Next, its combination with which granular-based material is evaluated through the CBR test procedure to determine its resistance and to compare it with the non-stabilized material. Finally, the behaviour of the material when subjected to dead loads by means of resistant modules found with the NAT (Nottingham Asphalt Tester) is explored. As a result, the option of using coal tar as a stabilizer was identified due to its use under specific conditions.

  3. National Assessment of Oil and Gas Project - Uinta-Piceance Province (020) Tar Sand Deposits

    U.S. Geological Survey, Department of the Interior — Tar sands represent a significant source of hydrocarbons in the United States. Also known by several other names including bitumen-bearing rocks, natural asphalt,...

  4. Identification of sources of tar balls deposited along the Goa coast, India, using fingerprinting techniques.

    Suneel, V; Vethamony, P; Zakaria, M P; Naik, B G; Prasad, K V S R

    2013-05-15

    Deposition of tar balls along the coast of Goa, India is a common phenomenon during the southwest monsoon. Representative tar ball samples collected from various beaches of Goa and one Bombay High (BH) crude oil sample were subjected to fingerprint analysis based on diagnostic ratios of n-alkane, biomarkers of pentacyclic tri-terpanes and compound specific stable carbon isotope (δ¹³C) analysis to confirm the source. The results were compared with the published data of Middle East Crude Oil (MECO) and South East Asian Crude Oil (SEACO). The results revealed that the tar balls were from tanker-wash derived spills. The study also confirmed that the source is not the BH, but SEACO. The present study suggests that the biomarkers of alkanes and hopanes coupled with stable carbon isotope analysis act as a powerful tool for tracing the source of tar balls, particularly when the source specific biomarkers fail to distinguish the source. PMID:23522683

  5. Work plan for integrated sludge packaging demonstration

    This document describes the tasks which will be performed to support the hot demonstration of the integrated sludge packaging system to package the sludge that has accumulated in the KE Basin. This activity will be performed in three phases: Phase 1 will consist of testing component and sub-system performance using a surrogate sludge, Phase 2 will consist of cold testing the integrated sludge packaging system using a surrogate sludge, and Phase 3 will consist of the hot demonstration of the integrated sludge packaging system

  6. Thermo-chemical process with sewage sludge by using CO2.

    Kwon, Eilhann E; Yi, Haakrho; Kwon, Hyun-Han

    2013-10-15

    This work proposed a novel methodology for energy recovery from sewage sludge via the thermo-chemical process. The impact of CO2 co-feed on the thermo-chemical process (pyrolysis and gasification) of sewage sludge was mainly investigated to enhance thermal efficiency and to modify the end products from the pyrolysis and gasification process. The CO2 injected into the pyrolysis and gasification process enhance the generation of CO. As compared to the thermo-chemical process in an inert atmosphere (i.e., N2), the generation of CO in the presence of CO2 was enhanced approximately 200% at the temperature regime from 600 to 900 °C. The introduction of CO2 into the pyrolysis and gasification process enabled the condensable hydrocarbons (tar) to be reduced considerably by expediting thermal cracking (i.e., approximately 30-40%); thus, exploiting CO2 as chemical feedstock and/or reaction medium for the pyrolysis and gasification process leads to higher thermal efficiency, which leads to environmental benefits. This work also showed that sewage sludge could be a very strong candidate for energy recovery and a raw material for chemical feedstock. PMID:23792821

  7. Criteria for selection of dolomites and catalysts for tar elimination from biomass gasification gas. Kinetic constants

    Corella, J.; Narvaez, I.; Orio, A. [Madrid Univ. (Spain). Dept. of Chem. Eng.

    1996-12-31

    Calcined dolomites and commercial steam reforming catalysts are used downstream biomass gasifiers for hot catalytic raw gas cleaning. To further compare these solids under a rigorous basis, a reaction network and a kinetic model are presented. The apparent kinetic constant for the tar reduction is here proposed as a basis of comparison. Tar sampling and analysis, and the units used for the space-time in the catalytic reactor affect the kinetic constants observed. (author) (2 refs.)

  8. Integrated Biomass Gasification with Catalytic Partial Oxidation for Selective Tar Conversion

    Zhang, Lingzhi; Wei, Wei; Manke, Jeff; Vazquez, Arturo; Thompson, Jeff; Thompson, Mark

    2011-05-28

    Biomass gasification is a flexible and efficient way of utilizing widely available domestic renewable resources. Syngas from biomass has the potential for biofuels production, which will enhance energy security and environmental benefits. Additionally, with the successful development of low Btu fuel engines (e.g. GE Jenbacher engines), syngas from biomass can be efficiently used for power/heat co-generation. However, biomass gasification has not been widely commercialized because of a number of technical/economic issues related to gasifier design and syngas cleanup. Biomass gasification, due to its scale limitation, cannot afford to use pure oxygen as the gasification agent that used in coal gasification. Because, it uses air instead of oxygen, the biomass gasification temperature is much lower than well-understood coal gasification. The low temperature leads to a lot of tar formation and the tar can gum up the downstream equipment. Thus, the biomass gasification tar removal is a critical technology challenge for all types of biomass gasifiers. This USDA/DOE funded program (award number: DE-FG36-O8GO18085) aims to develop an advanced catalytic tar conversion system that can economically and efficiently convert tar into useful light gases (such as syngas) for downstream fuel synthesis or power generation. This program has been executed by GE Global Research in Irvine, CA, in collaboration with Professor Lanny Schmidt's group at the University of Minnesota (UoMn). Biomass gasification produces a raw syngas stream containing H2, CO, CO2, H2O, CH4 and other hydrocarbons, tars, char, and ash. Tars are defined as organic compounds that are condensable at room temperature and are assumed to be largely aromatic. Downstream units in biomass gasification such as gas engine, turbine or fuel synthesis reactors require stringent control in syngas quality, especially tar content to avoid plugging (gum) of downstream equipment. Tar- and ash-free syngas streams are a critical

  9. An optical analysis of the organic soil over an old petroleum tar deposit

    Gillet, Servane; PONGE, Jean-François

    2006-01-01

    International audience We analysed by an optical method (the small volume method) the composition and the vertical distribution of an organic soil which accumulated over an old petroleum tar deposit. The study site was an oil refinery now colonised by woody vegetation since the time of abandonment (1964), located at Merkwiller-Pechelbronn (Alsace, France). Comparisons were done with a nearby unpolluted control plot under similar vegetation. The humus form over the tar deposit was described...

  10. Influence of Pyrolysis Temperature on Rice Husk Char Characteristics and Its Tar Adsorption Capability

    Anchan Paethanom; Kunio Yoshikawa

    2012-01-01

    A biomass waste, rice husk, was inspected by thermoanalytical investigation to evaluate its capability as an adsorbent medium for tar removal. The pyrolysis process has been applied to the rice husk material at different temperatures 600, 800 and 1000 °C with 20 °C/min heating rate, to investigate two topics: (1) influence of temperature on characterization of rice husk char and; (2) adsorption capability of rice husk char for tar removal. The results showed that subsequent ...

  11. Gas chromatographic-mass spectrometric analysis of tar compounds formed during pyrolysis of rice husks

    Haanappel, V.A.C.; Stevens, T.W.; Hovestad, A.; Skolnik, V.; Visser, R.

    1991-01-01

    Pyrolysis of agricultural waste to produce fuel gas involves formation of tars as noxious by-products. In this paper the qualitative analysis of tars formed during pyrolysis of rice husks is presented, based on identification by gas chromatography—mass spectrometry and interpolation of retention times on a polyaromatic hydrocarbon index scale. The influence of some reaction parameters on product formation is briefly discussed.

  12. Feasibility study of tar sands conditioning for earth pressure balance tunnelling

    Martinelli, D; D. Peila; E. Campa

    2015-01-01

    This paper presents the results of laboratory test on the feasibility of soil conditioning for earth pressure balance (EPB) excavation in a tar sand, which is a natural material never studied in this respect. The laboratory test performed is based on a procedure and methods used in previous studies with different types of soils, but for this special complex material, additional tests are also conducted to verify particular properties of the tar sands, such as the tilt test and vane shear test...

  13. Activated sewage sludge, a potential animal foodstuff. Part I. Proximate and mineral content; seasonal variation

    Tacon, A.G.J.; Ferns, P.N.

    1979-08-01

    A detailed proximate and mineral analysis of activated sewage sludge is described. Samples were collected at bi-weekly intervals from a rural domestic sewage works for one year. The following annual ranges and mean values were determined for the chemical components within the sludge samples: moisture, total nitrogen, crude protein, Lowry protein, fat, saponification value, available carbohydrate as glucose, fiber, ash, acid insoluble ash, and 26 elements. The seasonal variation patterns observed are discussed. 23 references

  14. Effects of pre-treatments on the lipid extraction and biodiesel production from municipal WWTP sludge

    Olkiewicz, Magdalena; Fortuny Sanromá, Agustín; Stüber, Frank Erich; Fabregat Llagostera, Azael; Font Capafons, Josep; Bengoa, Christophe José

    2015-01-01

    Biodiesel production is currently limited due to high raw material costs. The potential of using sludge from municipal wastewater treatment plants as an alternative lipid feedstock was investigated. Four different types of sludge (primary, secondary, blended and stabilised) were tested in lipid extraction by Soxhlet using hexane, and biodiesel production by acid catalysis. To improve the extraction efficiency, the influence of pre-treatment methods (ultrasonic and mechanical disintegration) a...

  15. Microbiological and biochemical properties of an agricultural Mexican soil amended with sewage sludge

    Renato Armenta; Rocio Vaca; Jorge Lugo; Pedro del Aguila

    2012-01-01

    The application of sewage sludge is a concern because it may affect the quality of organic matter and microbiological and biochemical soil properties. The effects of surface application of sewage sludge to an agricultural soil (at 18 and 36 t ha-1 dry basis) were assessed in one maize (Zea mays L.) growing season. The study evaluated microbial biomass, basal respiration and selected enzymatic activities (catalase, urease, acid and alkaline phosphatase, and β-glucosidase) 230 days after sewage...

  16. Small sized pilot scale experiments on the recovery cooper and nickel hydroxide from galvanic sludge

    Vilarinho, Cândida; de Castro, F.; Ribeiro, André

    2011-01-01

    The present work, carried out within the project VALMETAIS, proposes a hydrometallurgical process for copper and nickel recovery from galvanic sludges produced by Ni/Cr plating plants. The procedure has been developed on laboratory scale and the results validation was verified in a small sized pilot scale. The project starts with a leaching process of sludge in sulphuric acid solution in three stages followed by copper cementation step, using iron scrap as precipitating agent. It was found...

  17. Gasification of municipal solid waste in a downdraft gasifier: Analysis of tar formation

    Tabitha Geoffrey Etutu

    2016-04-01

    Full Text Available In this study, municipal solid waste (MSW from a dumpsite was converted into refuse derived fuel (RDF and used as feedstock for an air-blown gasification process. The gasification process was conducted in a 10 kg.hr -1 downdraft gasifier at different air flow rates of 300, 350, 400, 450 and 550 NL.min1 at atmospheric pressure in order to investigate the quantity and quality of tar formed. It was shown that the increase in the air flow rate from 300 NL.min1 to 550 NL.min1 led to an increase in the oxidation temperature from 719°C to 870°C and an increase in the reduction temperature from 585°C to 750°C, respectively. Tar was reduced from 15 g.Nm3 to 4.7 g.Nm3 respectively. Heavy tar compounds (>C17 e.g. pyrene and phenathrene, decreased with the increase in the light tar compounds (tar reduction through a tar cracking process.

  18. Tar sands. Fuelling the climate crisis, undermining EU energy security and damaging development objectives

    Wykes, S.; Heywood, S.; Urbaniak, D. (ed.); De Clerck, P. (ed.)

    2010-05-15

    Tar sands - bitumen that is extracted and upgraded to produce synthetic crude - has been heavily criticised for its poor environmental and social outcomes, locally and globally. Tar sands generates on average 3 to 5 times more greenhouse gas (GHG) emissions than conventional oil, representing a huge threat to climate protection. Canada is currently the only major centre of production but investment is expanding, including by European oil companies such as BP, Shell, Total and ENI. The second part of this report shows which oil companies are increasing their investments in tar sands and oil shale, and where. In Canada, tar sands development is the fastest growing source of GHG emissions and is undermining the country's Kyoto commitments. Tar sands projects are also extremely costly and capital intensive - to the point where investors and analysts have raised concerns about their longer-term financial viability in a world where the introduction of low-carbon regulation and reduced demand for expensive fossil fuels are increasingly likely. A more strategic approach to energy policy would encourage redirection of the hundreds of billions to be invested over the next decade in tar sands production in Canada alone into development of renewable fuel technologies and energy efficiency measures.

  19. A feasibility study to use coal tar contaminated soil in asphalt cement mixture production

    Coal tars are the residues produced during the gasification of coal. Traditionally, coal tars were buried onsite at the power plants or left as residuals in the bottom of gas holders. Currently, there are more than 1,500 such historic sites which will undergo site assessment in the near future. The use of coal tar residuals in asphalt-based products could result in greatly reduced disposal costs, in comparison to current methods of disposal. Present disposal practice of coal tar contaminated residuals includes disposal in hazardous waste landfills or incineration. Treatment and disposal costs are reported to be as much as $1,000/ton for current coal tar contaminated residuals disposal options. This feasibility study was performed to determine the use of coal tar contaminated soil (CTCS) in bituminous materials to produce hot asphalt mix. Mixtures of varying composition of CTCS and bituminous material were produced to perform TCLP. The air emissions during the mixing process were captured and analyzed. In this study, a bench scale investigation was performed to identify and quantify the emissions from heating the CTCS at the mixer temperature. The pilot scale investigations were performed by replacing reclaimable asphalt pavement (RAP) with CTCS during the hot asphalt mix production. The investigations were performed on two types of mixtures; using CTCS as the direct additive in the first type, and using SS-1 (slow setting asphalt emulsion) stabilized CTCS as an additive in the second type

  20. A feasibility study to use coal tar contaminated soil in asphalt cement mixture production

    Dulam, C.S.; Hoag, G.E.; Dahmani, A.; Nadim, F. [Univ. of Connecticut, Storrs, CT (United States). Environmental Research Inst.

    1996-11-01

    Coal tars are the residues produced during the gasification of coal. Traditionally, coal tars were buried onsite at the power plants or left as residuals in the bottom of gas holders. Currently, there are more than 1,500 such historic sites which will undergo site assessment in the near future. The use of coal tar residuals in asphalt-based products could result in greatly reduced disposal costs, in comparison to current methods of disposal. Present disposal practice of coal tar contaminated residuals includes disposal in hazardous waste landfills or incineration. Treatment and disposal costs are reported to be as much as $1,000/ton for current coal tar contaminated residuals disposal options. This feasibility study was performed to determine the use of coal tar contaminated soil (CTCS) in bituminous materials to produce hot asphalt mix. Mixtures of varying composition of CTCS and bituminous material were produced to perform TCLP. The air emissions during the mixing process were captured and analyzed. In this study, a bench scale investigation was performed to identify and quantify the emissions from heating the CTCS at the mixer temperature. The pilot scale investigations were performed by replacing reclaimable asphalt pavement (RAP) with CTCS during the hot asphalt mix production. The investigations were performed on two types of mixtures; using CTCS as the direct additive in the first type, and using SS-1 (slow setting asphalt emulsion) stabilized CTCS as an additive in the second type.

  1. HIV-1 TAR RNA-binding proteins control TAT activation of translation in Xenopus oocytes.

    Braddock, M; Powell, R; Blanchard, A D; Kingsman, A J; Kingsman, S M

    1993-01-01

    Human immunodeficiency virus (HIV-1) gene expression is activated by the viral TAT protein that interacts with an RNA sequence, TAR, located at the 5' end of all viral mRNAs. TAT functions primarily as a transcriptional activator in mammalian cells. However, in Xenopus oocytes TAT functions primarily as a translational activator. TAR is an RNA structure comprising a partially base-paired stem, a tripyrimidine bulge in the upper stem, and an unpaired six-nucleotide loop. In vitro, TAT binds directly to the bulge with no requirement for the loop. In vivo, however, mutations in the loop abolish TAT activation of transcription and translation, implying a requirement for TAR-binding cellular factors. We now provide genetic evidence for the presence of two TAR-specific cellular factors in Xenopus oocytes. These factors display independent and mutually exclusive interactions with either the loop or the bulge region of TAR. Furthermore, by using in vivo RNA competition assays we show that the cellular factors regulate the accessibility of the TAT binding site. The fact that Xenopus oocytes contain factors that specifically interact with a human viral RNA sequence might indicate that the TAT/TAR interaction is subverting a conserved pathway in the cell. PMID:8422967

  2. Source targeting tar balls along the southern Louisiana coastline

    Stranded oil and tarballs deposited along the southern coast of Louisiana were source targeted, or compared for petroleum similarities, during 1992. The distribution, frequency, and composition of the stranded oil was assessed for specific study sites covering about 200 miles of the Louisiana coastline. Petroleum transportation off Louisiana shores is in the millions of barrels; with the Louisiana Offshore Oil Port receiving more than 200 million barrels per year. Also contributing to this transportation system are the outer continental shelf production activities, transporting 98 percent of their production by pipeline and 2 percent by barge. The questions addressed here are: What are the sources of the stranded oil and tar found upon the beaches? Are they primarily from small unrelated events, or are they from chronic discharges of identifiable sources? Preliminary data indicates a wide range of petroleum sources, with bunker oils most abundant. The petroleum has undergone varying degrees of weathering, or degradation by environmental processes. Preliminary data indicate relatively undegraded as well as extremely degraded petroleum, with no apparent correlation with study stations. Stations selected along the coastline were biannually surveyed, and petroleum samples collected were quantitatively assessed for petroleum per square meter per station. For a complete chemical assessment, the samples were qualitatively analyzed by detailed gas chromatography/mass spectrometry (GC/MS) characterization and source fingerprinting using selective ion monitoring (SIM). The results were plotted in a cluster matrix to highlight the number of possible sources and the chemical characteristics of the petroleum found

  3. Studies of RF sheaths and diagnostics on IShTAR

    Crombé, K.; Devaux, S.; D'Inca, R.; Faudot, E.; Faugel, H.; Fünfgelder, H.; Heuraux, S.; Jacquot, J.; Louche, F.; Moritz, J.; Ochoukov, R.; Tripsky, M.; Van Eester, D.; Wauters, T.; Noterdaeme, J.-M.

    2015-12-01

    IShTAR (Ion cyclotron Sheath Test ARrangement) is a linear magnetised plasma test facility for RF sheaths studies at the Max-Planck-Institut für Plasmaphysik in Garching. In contrast to a tokamak, a test stand provides more liberty to impose the parameters and gives better access for the instrumentation and antennas. The project will support the development of diagnostic methods for characterising RF sheaths and validate and improve theoretical predictions. The cylindrical vacuum vessel has a diameter of 1 m and is 1.1 m long. The plasma is created by an external cylindrical plasma source equipped with a helical antenna that has been designed to excite the m=1 helicon mode. In inductive mode, plasma densities and electron temperatures have been characterised with a planar Langmuir probe as a function of gas pressure and input RF power. A 2D array of RF compensated Langmuir probes and a spectrometer are planned. A single strap RF antenna has been designed; the plasma-facing surface is aligned to the cylindrical plasma to ease the modelling. The probes will allow direct measurements of plasma density profiles in front of the RF antenna, and thus a detailed study of the density modifications induced by RF sheaths, which influences the coupling. The RF antenna frequency has been chosen to study different plasma wave interactions: the accessible plasma density range includes an evanescent and propagative behaviour of slow or fast waves, and allows the study of the effect of the lower hybrid resonance layer.

  4. Kinetics of co-pyrolysis of sawdust, coal and tar.

    Montiano, M G; Díaz-Faes, E; Barriocanal, C

    2016-04-01

    Two coals, sawdust and coal tar were selected to prepare briquettes. Thermogravimetric analyses at three heating rates (i.e. 10, 20 and 30°C/min) and up to 1000°C were carried out with the briquette components. Four blends were prepared and the experimental decomposition profiles were compared with the calculated data taking into account the amount of each component in the blend. No interaction was found when comparing the experimental and calculated decomposition profiles of the blends. Isoconversional models OFW (Ozawa-Flynn-Wall) and KAS (Kissinger-Akahira-Sunose) were used to obtain the activation energies of the blend components. The activation energies obtained were introduced in the Coats-Redfern (CR) model to derive the pre-exponential factors. The thermal decomposition profiles calculated using the kinetic parameters were in good agreement with the experimental results in the case of the briquette components, but worse results were obtained in the case of the blends due to their greater complexity. PMID:26829530

  5. First experimental results on the IShTAR testbed

    D’Inca, R.; Jacquot, J.; Ochoukov, R.; Morgal, I.; Fünfgelder, H.; Faugel, H. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Crombe, K.; Louche, F.; Van Eester, D. [LPP-ERM-KMS, TEC partner, Brussels (Belgium); Heuraux, S.; Devaux, S.; Moritz, J.; Faudot, E. [Institut Jean Lamour UMR 7198 CNRS-Université de Lorraine, Nancy (France); Noterdaeme, J.-M. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Department of Applied Physics, Ghent University (Belgium)

    2015-12-10

    IShTAR (Ion cyclotron Sheath Test ARrangement) is a linear magnetized plasma test facility dedicated to the investigation of RF wave/plasma interaction [1] in the Ion Cyclotron Range of Frequencies (ICRF). It provides a better accessibility for the instrumentation than tokamaks while being representative of the neighboring region of the wave emitter. It is equipped with a magnetized plasma source (1 m long, 0.4 m diameter) powered by a helical antenna up to 3 kW at 11 MHz. We present the results of the first analysis of the plasma characteristics (plasma density, electron temperature) in function of the operating parameters (injected power, neutral pressure and magnetic field) as measured with fixed and movable Langmuir probes, spectrometer and cameras. The plasma is presently produced only by the helical antenna (no ICRF). We show that the plasma exists in three regime depending on the power level: the first two ones are stable and separated by a jump in density; a first spatial profile of the plasma density has been established for these modes; The third mode is unstable, characterized by strong oscillations of the plasma tube position.

  6. Topical tazarotene vs. coal tar in stable plaque psoriasis

    Kumar, U.; Kaur, I.; Dogra, S.; De, D.; Kumar, B. [Postgraduate Institute of Medical Education & Research, Chandigarh (India)

    2010-07-15

    The efficacy of topical tazarotene has not previously been compared with the conventional topical treatment of crude coal tar (CCT) in stable plaque psoriasis. In this nonblinded side-to-side comparison study, patients with chronic stable plaque psoriasis, who had bilaterally symmetrical plaques on the limbs, applied 0.1% tazarotene gel on the right side and 5% CCT ointment on the left side once daily for 12 weeks followed by an 8-week treatment-free follow up period. Severity of psoriatic lesions and response to treatment was evaluated by scoring erythema, scaling and induration (ESI). Of 30 patients recruited, 27 could be assessed. In the per-protocol analysis, the mean percentage reduction in ESI score at the end of the treatment period was 74.15% {+-} 9.43 and 77.37% {+-} 10.93 with tazarotene and CCT, respectively (P {gt} 0.05). A reduction in ESI score of {gt} 75% was seen in 11 (40.74%) and 16 (59.26%) patients with tazarotene and CCT, respectively, at the end of 12 weeks. Side-effects were seen in 48.14% of patients treated with tazarotene, but in no patient treated with CCT. Tazarotene 0.1% gel has comparable clinical efficacy to CCT 5% ointment. CCT ointment remains a cost-effective therapy for plaque psoriasis.

  7. Structural and dynamic characterization of the upper part of the HIV-1 cTAR DNA hairpin.

    Zargarian, Loussiné; Kanevsky, Igor; Bazzi, Ali; Boynard, Jonathan; Chaminade, Françoise; Fossé, Philippe; Mauffret, Olivier

    2009-07-01

    First strand transfer is essential for HIV-1 reverse transcription. During this step, the TAR RNA hairpin anneals to the cTAR DNA hairpin; this annealing reaction is promoted by the nucleocapsid protein and involves an initial loop-loop interaction between the apical loops of TAR and cTAR. Using NMR and probing methods, we investigated the structural and dynamic properties of the top half of the cTAR DNA (mini-cTAR). We show that the upper stem located between the apical and the internal loops is stable, but that the lower stem of mini-cTAR is unstable. The residues of the internal loop undergo slow motions at the NMR time-scale that are consistent with conformational exchange phenomena. In contrast, residues of the apical loop undergo fast motions. The lower stem is destabilized by the slow interconversion processes in the internal loop, and thus the internal loop is responsible for asymmetric destabilization of mini-cTAR. These findings are consistent with the functions of cTAR in first strand transfer: its apical loop is suitably exposed to interact with the apical loop of TAR RNA and its lower stem is significantly destabilized to facilitate the subsequent action of the nucleocapsid protein which promotes the annealing reaction. PMID:19417069

  8. Catalytic decomposition of tar derived from wood waste pyrolysis using Indonesian low grade iron ore as catalyst

    Wicakso, Doni Rahmat; Sutijan, Rochmadi, Budiman, Arief

    2016-06-01

    Low grade iron ore can be used as an alternative catalyst for bio-tar decomposition. Compared to other catalysts, such as Ni, Rd, Ru, Pd and Pt, iron ore is cheaper. The objective of this research was to investigate the effect of using low grade iron ore as catalyst for tar catalytic decomposition in fixed bed reactor. Tar used in this experiment was pyrolysis product of wood waste while the catalyst was Indonesian low grade iron ore. The variables studied were temperatures between 500 - 600 °C and catalyst weight between 0 - 40 gram. The first step, tar was evaporated at 450 °C to produce tar vapor. Then, tar vapor was flowed to fixed bed reactor filled low grade iron ore. Gas and tar vapor from reactor was cooled, then the liquid and uncondensable gas were analyzed by GC/MS. The catalyst, after experiment, was weighed to calculate total carbon deposited into catalyst pores. The results showed that the tar components that were heavy and light hydrocarbon were decomposed and cracked within the iron ore pores to from gases, light hydrocarbon (bio-oil) and carbon, thus decreasing content tar in bio-oil and increasing the total gas product. In conclusion, the more low grade iron ore used as catalyst, the tar content in the liquid decrease, the H2 productivity increased and calorimetric value of bio-oil increased.

  9. Fractionation and business potential from sludge - Pafrak

    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.)

  10. Effect and behaviour of different substrates in relation to the formation of aerobic granular sludge.

    Pronk, M; Abbas, B; Al-Zuhairy, S H K; Kraan, R; Kleerebezem, R; van Loosdrecht, M C M

    2015-06-01

    When aerobic granular sludge is applied for industrial wastewater treatment, different soluble substrates can be present. For stable granular sludge formation on volatile fatty acids (e.g. acetate), production of storage polymers under anaerobic feeding conditions has been shown to be important. This prevents direct aerobic growth on readily available chemical oxygen demand (COD), which is thought to result in unstable granule formation. Here, we investigate the impact of acetate, methanol, butanol, propanol, propionaldehyde, and valeraldehyde on granular sludge formation at 35 °C. Methanogenic archaea, growing on methanol, were present in the aerobic granular sludge system. Methanol was completely converted to methane and carbon dioxide by the methanogenic archaeum Methanomethylovorans uponensis during the 1-h anaerobic feeding period, despite the relative high dissolved oxygen concentration (3.5 mg O2 L(-1)) during the subsequent 2-h aeration period. Propionaldehyde and valeraldehyde were fully disproportionated anaerobically into their corresponding carboxylic acids and alcohols. The organic acids produced were converted to storage polymers, while the alcohols (produced and from influent) were absorbed onto the granular sludge matrix and converted aerobically. Our observations show that easy biodegradable substrates not converted anaerobically into storage polymers could lead to unstable granular sludge formation. However, when the easy biodegradable COD is absorbed in the granules and/or when the substrate is converted by relatively slow growing bacteria in the aerobic period, stable granulation can occur. PMID:25616527

  11. Pentachlorophenol (PCP) sludge recycling unit

    The Guelph Utility Pole Company treats utility poles by immersion in pentachlorophenol (PCP) or by pressure treatment with chromated copper arsenate (CCA). The PCP treatment process involves a number of steps, each producing a certain amount of sludge and other wastes. In a plant upgrading program to improve processing and treatment of poles and to reduce and recycle waste, a PCP recovery unit was developed, first as an experimental pilot-scale unit and then as a full-scale unit. The PCP recovery unit is modular in design and can be modified to suit different requirements. In a recycling operation, the sludge is pumped through a preheat system (preheated by waste heat) and suspended solids are removed by a strainer. The sludge is then heated in a tank and at a predetermined temperature it begins to separate into its component parts: oil, steam, and solids. The steam condenses to water containing low amounts of light oil, and this water is pumped through an oil/water separator. The recovered oil is reused in the wood treatment process and the water is used in the CCA plant. The oil remaining in the tank is reused in PCP treatment and the solid waste, which includes small stones and wood particles, is removed and stored. By the third quarter of operation, the recovery unit was operating as designed, processing ca 10,000 gal of sludge. This sludge yielded 6,500 gal of water, 3,500 gal of oil, and ca 30 gal of solids. Introduction of the PCP sludge recycling system has eliminated long-term storage of PCP sludge and minimized costs of hazardous waste disposal. 4 figs

  12. Experimental studies of relevance on zirconium nitrate raffinate sludge for its disposal as well as zirconium recovery

    One of the many routes of production of nuclear grade zirconium dioxide involve separation of zirconium and hafnium by solvent extraction of zirconium nitrate using tri-n-butyl phosphate followed by precipitation of zirconium with ammonia and finally calcination of the so obtained hydrated zirconia at elevated temperature. The zirconium feed solution as is generated from digestion of zirconium washed dried frit (produced by the caustic fusion of zircon sand which is one of the beach sand heavy minerals) in nitric acid contain considerable amount of sludge material and after solvent extraction this whole sludge material rests with raffinate. This sludge material has a scope to contain considerable amounts of zirconium along with other metal ions such as hafnium, aluminium, iron, etc. besides nitric acid and it constitutes one of the important solid wastes that needs to be disposed suitably. One of the disposal means of this sludge material is to use it as a land fill for which two important criteria are to be viz the pH of 10% solid waste solution should be near to neutral pH and the loss on ignition at 550℃ on dry basis of the sludge to be below 20%. In order to study the implications of presence of varying amounts of zirconium nitrate in the sludge on the pH of 10% solution of the sludge various synthetic zirconium nitrate solid waste were prepared using the sludge material generated at the laboratory during the analysis of zirconium washed dried frit. Presence of zirconium in the sludge is expected to decrease the overall pH of the 10% solution of the sludge because zirconium is prone to hydrolyze especially locally when zirconium ion comes into contact with water according to the chemical equation Zr4+ H2O → ZrO2++ 2H+ . From this equation, it is clear that for every one mole of zirconium ions two moles of hydrogen ions are produced. This is verified experimentally using the synthetically prepared sludge materials with varying amounts of zirconium. Thus, the

  13. The Chemical Composition and Physical Properties of the Light and Heavy Tar Resulted from Coconut Shell Pyrolysis

    Uswatun Hasanah

    2012-10-01

    Full Text Available The tar resulted from pyrolysis of coconut shell is a waste. It is important to be clarified their chemical composition and physical properties in order to find out their feasibility as source of a fuel. This research was resulted two immiscible organic fractions, and these were further determined their physical properties such as water composition by using ASTM D-95 methods, ash composition (ASTM D-482, flash point C.O.C (ASTM D-92, kinematics of viscosity (ASTM D-445, and caloric valued using bomb calorimetric. In addition, tar composition was determined by gas chromatography-mass spectrometry (GCMS. The result provided oil which was categorized as light and heavy bio-oils. The light bio-oil has specific gravity 0.99, ash content 0.01%, kinematics viscosity 25.5 cSt, flash point <27 oC, pH 3 and heating value 10304 kcal/kg. On the other hand, heavy bio- oils gave specific gravity 1.13, ash 0.46%, kinematics viscosity 185 cSt, flash point 134 oC, pH 2.5 and heating value 6210 kcal/kg. Moreover, the light bio-oil contained 79 compounds which was composed of phenol 16.4%, hydrocarbon 12.4%, phenolic 27.6%, other oxygenated compounds 53.6%, and acetic acid 3%, meanwhile the heavy bio-oils contained of 18 compounds which was consisted of phenol 31.2%, lauric acid 6.0%, phenolic 27.6%, and other oxygenated compounds 35.3%, respectively. With this result, it was clarify that these bio-oils could not be used directly as a fuel for motor nor diesel machinery.

  14. Formation and degradation of valuable intermediate products during wet oxidation of municipal sludge.

    Baroutian, Saeid; Gapes, Daniel J; Sarmah, Ajit K; Farid, Mohammed M; Young, Brent R

    2016-04-01

    The current study investigated the formation of organic acids and alcohols as major intermediate products of wet oxidation of municipal sludge. Municipal sludge was subjected to 60-min wet oxidation at temperatures ranging from 220 to 240°C, with 20bar oxygen partial pressure. Acetic acid was the main intermediate compound produced in this study, followed by propionic, n-butyric, iso-butyric and pentanoic acids and methanol. It was found that the process severity has a significant influence on the formation and degradation of these intermediate products. PMID:26832394

  15. Radiation hygienization of raw sewage sludge

    'Radiation treatment of municipal sewage sludge can achieve resource conservation and recovery objectives. The liquid sludge irradiator of Sludge Hygienization Research Irradiator at Baroda (India) was operated for generating data on treatment of raw sludge containing 3-4 % solids. The plant system was modified for irradiating raw sludge without affecting basic irradiator initially designed to treat digested sludge. Hourly samples were analysed for estimation of disinfection dose requirement. Sand separated from the sludge was used as in-situ dosimeter by making use of its thermoluminescence property. Investigations are being carried out for regrowth of Total Coliforms in the sludge samples from this irradiator. Possibility of inadequate treatment due to geometric configuration of irradiator is being checked. (author)

  16. Electron beam disinfection of sewage sludge

    Electron beam treatment of dehydrated sewage sludge for safe reutilization was performed. Ranges of total bacterial counts and total coliforms in the sludge were from 1.5 x 108 to 1.6 x 109 and from 2.2 x 107 to 1.5 x 108 per wet gram, respectively. Total bacterial counts decreased about 5 log cycles after irradiating 5 kGy and irradiation with 2 kGy was enough to kill all coliforms in sewage sludge. The survival curves of total bacteria, obtained by irradiation in oxygen atmosphere, approached to that in nitrogen atmosphere with the increase of sludge thickness. No effects of dose rate and electron energy were found when the sludge layers were thin enough. Continuous disinfection of sewage sludge cake, with the maximum feed rate of 300 kg-sludge/hr, was successfully performed with a Cockcroft-Walton type electron accelerator, a sludge pump and a flat nozzle. (J.P.N.)

  17. Evaluation of forest trees growth after sewage sludge application

    Vaitkutä--, Dovilé; Balträ--Naitä--, Edita; Booth, Colin A.; Fullen, Michael A.; Pereira, Paulo

    2010-05-01

    Sewage sludge is extensively used in forest to improve soil properties. It is expected that sewage sludge rich in phosphorus, nitrogen and organic material enhance the germination of tree seedlings in poor soils. In Lithuania, the deforested soils are highly acid, and have a lack of nutrients, especially in exploited peat areas. Sewage sludge from industry contains beneficial components for the soils (such as organic matter, phosphorus, nitrogen, calcium, magnesium, etc.). However, it is also rich in heavy metals, especially Cd, Pb, Cu and Zn. High heavy metals concentrations in soil can be phytotoxic and cause reduced plant growth or plant death. The main objectives of this research was to determine the influence of industrial sewage sludge in the forestry and to highlight the idea that industrial sewage sludge containing metals does not favour development of birch and pine trees. The study was performed in Taruskos experimental plot in Panevezys region (Lithuania), amended with industrial sewage sludge ten years ago was afforestated with birch and pine seedlings. In order to observe the effects of the amendment in accumulation the mentioned metals and tree growth we collected data from trees in amended plot and control plot. The results showed that soil parameters were improved in the amended plot, in comparing with control site (higher pH, organic matter and cation exchange capacity). However, the growth of investigated trees was slower (e.g. birch roots, shoot, stem and leaves biomass was 40, 7.4, 18.6, 22% smaller than in control site. In pine case: 30, 1.2, 17, 36%, respectively; the stem height of birch was 16% and pine - 12% smaller than in control site). This reduced growth can be related with heavy metals concentration load on soil and accumulation in trees. Cu and Cd concentrations were higher in soil amended with sewage sludge comparing with control site (60 and 36%, respectively). Also, in contaminated trees Cu and Cd concentrations were higher (Cu

  18. Integral study of sewage sludges

    Sewage sludges are the by-product generated during the treatment process of waste water, and they are conformed by a solid phase which origin is the accumulation of pollutant materials which has been added to water during natural and anthropogenic activities. Its handling is one of the most serious problems faced by water treatment plants which involve the production, gathering, transportation, re utilization and final disposal of sewage sludges. The main purpose of this project is to perform a technical evaluation of the process of sewage sludge irradiation for its possible application as a choice for treatment and final disposal. Irradiation with gammas from Cobalt-60 shows effectiveness in disinfestation of sewage sludges, since they reduce six times the microbial population with a 7 KGy dose. In like manners with doses of 10 KGy is possible to bring down in 70 % the concentration of organic compounds, as well as to eliminate the presence of 6 to 22 organic compounds on samples of sewage sludges. The whole content of this work is presented in six sections: Introduction, Antecedents, Methodology, Conclusions, Suggestions and Bibliography. (Author)

  19. Effect of cations on activated sludge dewatering

    Raynaud, M.; Vaxelaire, J.; Héritier, P.; Baudez, J.C.

    2010-01-01

    Even after mechanical dewatering, the residual water within activated sludge remains high. Due to its complex structure, this material is usually extremely compressible and known to be difficult to dewater. The ability of sludge to dewater depends on its biological nature, its composition and also the type of treatment it comes from. Indeed, changes in ionic strength and in ionic composition of sludge affect the stability of structural properties of activated sludge and thus the dewatering...

  20. Hybrid Sludge Modeling in Water Treatment Processes

    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 ...

  1. Filterability and Sludge Concentration in Membrane Bioreactors

    Lousada-Ferreira, M

    2011-01-01

    The Thesis entitled “Filterability and Sludge Concentration in Membrane Bioreactors” aims at explaining the relation between Mixed Liquid Suspended Solids (MLSS) concentration, the amount of solids in the wastewater being treated, also designated as sludge, and filterability, being the ability of the sludge to be filtrated through a membrane, in a wastewater treatment system designated as Membrane Bioreactor (MBR). An MBR is a wastewater treatment system that combines an activated sludge proc...

  2. Evaluation of coagulation sludge from raw water treated with Moringa oleifera for agricultural use

    Jhon Jairo Feria

    2016-08-01

    Full Text Available Coagulation-flocculation is a physical-chemical process responsible for producing the largest amount of sludge in the purification of natural raw water. Conventionally, aluminum sulfate or alum has been used as a coagulant. However, disposal of the sludge produced has been problematic for the environment due to excess aluminum. Currently, the convenience of using natural coagulants such as seed extracts from Moringa oleifera (MO is being studied, although, the properties of sewage sludge produced and its possible reuse are unknown. In this paper the physical-chemical, nutritional and dangerous characteristics from MO sludge were evaluated by using standard methods to verify its potential use in agricultural soils. Results indicated that pH, electrical conductivity, ion exchange capacity, organic matter and micronutrients from sludge were suitable for application to soils with agricultural potential; but deficiency of macronutrients and presence of fecal coliforms limits it to be used as soil improver and not as fertilizer. Sludge stabilization with hydrated lime at doses greater than or equal to 3 % was effective to ensure the elimination of pathogenic microorganisms and to obtain a Class A sludge, unrestricted for agricultural use and suitable for acid soils.

  3. Comparison of extracellular polymeric substances (EPS) extraction from two different activated sludges.

    Zhang, Leiyan; Ren, Hongqiang; Ding, Lili

    2012-01-01

    The characteristics of extracellular polymeric substances (EPS) extracted with five different extraction protocols from two different activated sludges were studied. The results showed that the major EPS constituent extracted by centrifugation was protein for the sludge in sequencing batch reactor treating chemical wastewater, and nucleic acid for the sludge in moving bed biofilm reactor treating synthetic urban wastewater. The order of EPS extraction amounting from the two sludges was formaldehyde + NaOH > formaldehyde + heating > EDTA > heating > centrifugation. The different extraction methods, the wastewater type, and activated sludge source greatly affected the amount and composition of EPS. The chemical extracted methods were more effective than the physical methods in extracting EPS for the two sludges. Moreover, formaldehyde combined NaOH was most effective in extracting EPS for the two sludges. However, chemical extraction could contaminate the EPS solution, which was pointed out by infra-red analysis and was also proved by cell lyses during EPS extraction and carrying over of the chemical extractant. Therefore, this study highlights that the choice of EPS extraction method should consider both the extraction yield and content and the contamination of extracting reagents to the EPS solution. The extraction procedures should be optimized and most effective. PMID:22864444

  4. [Microbial composition of the activated sludges of the Moscow wastewater treatment plants].

    Kallistova, A Iu; Pimenov, N V; Kozlov, M N; Nikolaev, Iu A; Dorofeev, A G; Aseeva, V G; Grachev, V A; Men'ko, E V; Berestovskaia, Iu Iu; Nozhevnikova, A N; Kevbrina, M V

    2014-01-01

    The contribution of the major technologically important microbial groups (ammonium- and nitrite-oxidizing, phosphate-accumulating, foam-inducing, and anammox bacteria, as well as planctomycetes and methanogenic archaea) was characterized for the aeration tanks of the Moscow wastewater treatment facilities. FISH investigation revealed that aerobic sludges were eubacterial communities; the metabolically active archaea contributed insignificantly. Stage II nitrifying microorganisms and planctomycetes were significant constituents of the bacterial component of activated sludge, with Nitrobacter spp. being the dominant nitrifier. No metabolically active anammox bacteria were revealed in the sludge from aeration tanks. The sludge from the aeration tanks using different wastewater treatment technologies were found to differ in characteristics. Abundance of the nitrifying and phosphate-accumulating bacteria in the sludges generally correlated with microbial activity, in microcosms and with efficiency of nitrogen and phosphorus removal from wastewater. The highest microbial numbers and activity were found in the sludges of the tanks operating according to the technologies developed in the universities of Hanover and Cape Town. The activated sludge from the Novokur yanovo facilities, where abundant growth of filamentous bacteria resulted in foam formation, exhibited the lowest activity The group of foaming bacteria included Gordonia spp. and Acinetobacter spp., utilizing petroleum and motor oils, Sphaerotilus spp. utilizing unsaturated fatty acids, and Candidatus 'Microthrix parvicella'. Thus, the data on abundance and composition of metabolically active microorganisms obtained by FISH may be used for the technological control of wastewater treatment. PMID:25844473

  5. Long-term acclimation of anaerobic sludges for high-rate methanogenesis from LCFA

    Inhibition of methanogens by long chain fatty acids (LCFA) and the low numbers of LCFA-degrading bacteria are limitations to exploit biogas production from fat-rich wastewaters. Generally reactors fail due to excessive LCFA accumulation onto the sludge. Here, long-term acclimation and bioaugmentation with a LCFA-degrading coculture were hypothesized as strategies to enhance methanogenic conversion of these compounds. Anaerobic sludges previously exposed to LCFA for more than 100 days converted a specific biomass-associated substrate of (3.2 ± 0.1) kg·kg−1 with very short lag phases (<1 day), whereas non-acclimated sludges showed lag phases of 11–15 days for metabolizing (1.6–1.8) kg·kg−1. Addition of a coculture of Syntrophomonas zehnderi and Methanobacterium formicicum to sludges previously loaded with LCFA and containing different amounts of biomass-associated substrate (from (0.5–3.2) kg·kg−1) did not improve methane production neither lag phases were shortened, indicating that the endogenous microbiota are not a limiting factor. Clearly, we show that long-term sludge acclimation to LCFA is essential for high rate methanogenesis from LCFA. - Highlights: • Long-term sludge acclimation results in more resilient microbial communities to LCFA. • Excessive LCFA accumulation onto the biomass should be prevented. • Bioaugmentation does not improve methane production by LCFA-overloaded sludge

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

    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

  7. Alkaline Leaching of Low Zinc Content Iron-Bearing Sludges

    Gargul K.; Jarosz P.; Małecki S.

    2016-01-01

    Various types of waste materials containing zinc (e.g. dusts and sludges from gas dedusting process) are obtained in steel industry. The contents of Zn in these materials may vary considerably. Even a low concentration of zinc in recirculated products precludes their recycling in ferrous metallurgy aggregates. Long storage of this type of material can lead to contamination of soil and water by zinc compounds which can be leached out by acid rain, for example. This paper focuses on research in...

  8. Fractionation and business potential from sludge (Pafrak)

    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.)

  9. Supplementary information on K-Basin sludges

    MAKENAS, B.J.

    1999-03-15

    Three previous documents in this series have been published covering the analysis of: K East Basin Floor and Pit Sludge, K East Basin Canister Sludge, and K West Basin Canister Sludge. Since their publication, additional data have been acquired and analyses performed. It is the purpose of this volume to summarize the additional insights gained in the interim time period.

  10. Supplementary information on K-Basin sludges

    Three previous documents in this series have been published covering the analysis of: K East Basin Floor and Pit Sludge, K East Basin Canister Sludge, and K West Basin Canister Sludge. Since their publication, additional data have been acquired and analyses performed. It is the purpose of this volume to summarize the additional insights gained in the interim time period

  11. Studies of RF sheaths and diagnostics on IShTAR

    Crombé, K., E-mail: Kristel.Crombe@UGent.be [Department of Applied Physics, Ghent University, Ghent (Belgium); LPP-ERM/KMS, Royal Military Academy, Brussels (Belgium); Devaux, S.; Faudot, E.; Heuraux, S.; Moritz, J. [YIJL, UMR7198 CNRS-Université de Lorraine, Nancy (France); D’Inca, R.; Faugel, H.; Fünfgelder, H.; Jacquot, J.; Ochoukov, R. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Louche, F.; Tripsky, M.; Van Eester, D.; Wauters, T. [LPP-ERM/KMS, Royal Military Academy, Brussels (Belgium); Noterdaeme, J.-M. [Department of Applied Physics, Ghent University, Ghent (Belgium); Max-Planck-Institut für Plasmaphysik, Garching (Germany)

    2015-12-10

    IShTAR (Ion cyclotron Sheath Test ARrangement) is a linear magnetised plasma test facility for RF sheaths studies at the Max-Planck-Institut für Plasmaphysik in Garching. In contrast to a tokamak, a test stand provides more liberty to impose the parameters and gives better access for the instrumentation and antennas. The project will support the development of diagnostic methods for characterising RF sheaths and validate and improve theoretical predictions. The cylindrical vacuum vessel has a diameter of 1 m and is 1.1 m long. The plasma is created by an external cylindrical plasma source equipped with a helical antenna that has been designed to excite the m=1 helicon mode. In inductive mode, plasma densities and electron temperatures have been characterised with a planar Langmuir probe as a function of gas pressure and input RF power. A 2D array of RF compensated Langmuir probes and a spectrometer are planned. A single strap RF antenna has been designed; the plasma-facing surface is aligned to the cylindrical plasma to ease the modelling. The probes will allow direct measurements of plasma density profiles in front of the RF antenna, and thus a detailed study of the density modifications induced by RF sheaths, which influences the coupling. The RF antenna frequency has been chosen to study different plasma wave interactions: the accessible plasma density range includes an evanescent and propagative behaviour of slow or fast waves, and allows the study of the effect of the lower hybrid resonance layer.

  12. Effects of electric current upon catalytic steam reforming of biomass gasification tar model compounds to syngas

    Highlights: • ECR technique was proposed to convert biomass gasification tar model compounds. • Electric current enhanced the reforming efficiency remarkably. • The highest toluene conversion reached 99.9%. • Ni–CeO2/γ-Al2O3 exhibited good stability during the ECR performance. - Abstract: Electrochemical catalytic reforming (ECR) technique, known as electric current enhanced catalytic reforming technique, was proposed to convert the biomass gasification tar into syngas. In this study, Ni–CeO2/γ-Al2O3 catalyst was prepared, and toluene was employed as the major feedstock for ECR experiments using a fixed-bed lab-scale setup where thermal electrons could be generated and provided to the catalyst. Several factors, including the electric current intensity, reaction temperature and steam/carbon (S/C) ratio, were investigated to reveal their effects on the conversion of toluene as well as the composition of the gas products. Moreover, toluene, two other tar model compounds (benzene and 1-methylnaphthalene) and real tar (tar-containing wastewater) were subjected to the long period catalytic stability tests. All the used catalysts were analyzed to determine their carbon contents. The results indicated that the presence of electric current enhanced the catalytic performance remarkably. The toluene conversion reached 99.9% under the electric current of 4 A, catalytic temperature of 800 °C and S/C ratio of 3. Stable conversion performances of benzene, 1-methylnaphthalene and tar-containing wastewater were also observed in the ECR process. H2 and CO were the major gas products, while CO2 and CH4 were the minor ones. Due to the promising capability, the ECR technique deserves further investigation and application for efficient tar conversion

  13. Effect of temperature and dolomite on tar formation during gasification of torrefied biomass in a pressurized fluidized bed

    This work investigates the effect of temperature and bed material on the yields and composition of gas and tar produced from gasification of two types of biomass feedstock previously torrefied at 275 °C. Special attention was devoted to the evolution of tar composition under the different experimental conditions. Experiments were conducted in a fluidized bed reactor using two different types of bed material (sand and dolomite) under a constant pressure of 0.5 MPa and at two temperature levels (750 and 850 °C). Tar destruction reactions promoted by the catalyst (dolomite) enhanced the production of some of the gas components (H2, CO2, CO and CH4) whereas C2 hydrocarbons decreased, this effect being slightly more relevant at 850 °C. Comparable trends were observed with increasing temperature, which had a positive effect on cracking reactions and tar destruction. For both feedstocks, the increase in temperature resulted in (i) higher gas yields, and (ii) enhanced char gasification rate. On the other hand the evolution of tar yield and composition revealed a possible competition between two tar reaction pathways during gasification, (i) tar polymerization, and (ii) de-alkylation, dehydration and cracking of tars, depending on the experimental conditions and feedstock used. - Highlights: • An experimental study of pressurized gasification of torrefied biomass is presented. • Special attention was devoted to the evolution of tar composition. • Increasing temperature and dolomite presence led to higher gas and lower tar yields. • Tar evolution revealed a possible competition between two tar reaction pathways

  14. Radioactive sludge and wastewater analysis and treatment in the Hungarian VVER-440/213-type NPP

    It is well known that in the Hungarian VVER-type nuclear power plant Paks the radioactive waste waters are collected in common tanks. These water streams contain radioactive isotopes in ultra-low concentration and inactive compounds as major components (borate 1.7 g/dm3, sodium-nitrate 0.4 g/dm3, sodium-hydroxide 0.16 g/dm3, and oxalate 0.25 g/dm3). These low salinity solutions were evaporated by adding sodium-hydroxide, until 400 g/dm3 salt content is reached. There is about 6000 m3 concentrated evaporator bottom residues in the tanks of the reactor. There are some tanks at the power plant containing sludge type radioactive waste containing more or less liquid phase too. The general physical and chemical characteristics (density, pH, total solid, dissolved solid etc.) and chemical and radiochemical composition are important information for volume reduction and solidification treatment of these wastes. We have investigated and constructed a complex analysis system for the radioactive sludge and supernatant analysis, including the physical, as well as the chemical and radiochemical analysis methods. Using well known analysis techniques as ion chromatography, ICP-MS, AAS, gamma-and alpha-spectrometry and chemical alkaline fusion digestion and acidic dissolution methods we could analyze the main inorganic, organic and radioactive components of the sludges and supernatants. Determination of the mass and charge balance for the sludge samples were more difficult then for the supernatant samples. Not only are there assumptions required about the chemical form and the oxidation state of the species present in the sludge, but many of the compounds in the sludge are mixed oxides which are not directly measured. Also, the sludge is actually a slurry with a high water content. The interstitial liquid is in close contact with the sludge, and there are many ionic solubility equilibriums. The anion data for the sludge samples are based on the water soluble anions that would be

  15. Crystallization and preliminary X-ray diffraction analysis of the periplasmic domain of the Escherichia coli aspartate receptor Tar and its complex with aspartate

    Mise, Takeshi; Matsunami, Hideyuki; Samatey, Fadel A.; Maruyama, Ichiro N., E-mail: ichi@oist.jp [Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami, Okinawa 904-0495 (Japan)

    2014-08-27

    The periplasmic domain of the E. coli aspartate receptor Tar was cloned, expressed, purified and crystallized with and without bound ligand. The crystals obtained diffracted to resolutions of 1.58 and 1.95 Å, respectively. The cell-surface receptor Tar mediates bacterial chemotaxis toward an attractant, aspartate (Asp), and away from a repellent, Ni{sup 2+}. To understand the molecular mechanisms underlying the induction of Tar activity by its ligands, the Escherichia coli Tar periplasmic domain with and without bound aspartate (Asp-Tar and apo-Tar, respectively) were each crystallized in two different forms. Using ammonium sulfate as a precipitant, crystals of apo-Tar1 and Asp-Tar1 were grown and diffracted to resolutions of 2.10 and 2.40 Å, respectively. Alternatively, using sodium chloride as a precipitant, crystals of apo-Tar2 and Asp-Tar2 were grown and diffracted to resolutions of 1.95 and 1.58 Å, respectively. Crystals of apo-Tar1 and Asp-Tar1 adopted space group P4{sub 1}2{sub 1}2, while those of apo-Tar2 and Asp-Tar2 adopted space groups P2{sub 1}2{sub 1}2{sub 1} and C2, respectively.

  16. Preliminary Study on Pyrolysis of Wood Tar in Molten Salt Media%熔融盐裂解木焦油的初步研究

    吕红云; 于凤文; 唐强; 计建炳

    2012-01-01

    Catalytic cracking reactions was performed using wood tar as raw material under the catlysis of molten salt in fixed-bed cracking reactor. The influence of cracking temperature on the components of product was investigated. The chemical components of wood tar and secondary cracking products were analyzed using gas chromatograph with mass selective detector ( GC-MS). It was found that the wood tar is mainly compsed of guaiacol, 4-ethyl guaiacol, 4-methyl guaiacol, 3-methyl phenol, diacetone alcohol etc. Combination of high cracking temperature and low feed rate are beneficial to the cracking reaction of tar. The secondary cracking of tar yield could reach 16. 47% under the reaction conditions of temperature 500℃ and the feeding rate 1 g/min. Under the effect of molten salt, the amount of acids, ketones, esters and phenanthrene was significantly reduced. The conversion of phenol is lower than other fractions, and other fractions can be converted phenolic fractions.%以木焦油为原料,在自制的反应器上利用ZnCl2和KCI混合盐分别在300、350、400、450和500℃下,对木焦油进行裂解试验,利用GC -MS分析木焦油裂解前后组成的变化.结果表明:木焦油的主要成分为愈创木酚、4-乙基愈创木酚、4-甲基愈创木酚、间甲酚及二丙酮醇等.较高的熔融盐温度、较低的进料速率有利于木焦油的裂解,在裂解温度为500℃,进料速率为1 g/min时,二次裂解焦油的得率为16.47%.在高温熔融盐作用下,酸、酮、酯及菲都有较明显的减少,酚类的转化较少,并且还存在其它组分向酚类的转化.

  17. Arsenic in an alkaline AMD treatment sludge: Characterization and stability under prolonged anoxic conditions

    Lime treatment of acid mine drainage (AMD) generates large volumes of neutralization sludge that are often stored under water covers. The sludge consists mainly of calcite, gypsum and a widespread ferrihydrite-like Fe phase with several associated species of metal(loid) contaminants. The long-term stability of metal(loid)s in this chemically ill-defined material remains unknown. In this study, the stability and speciation of As in AMD sludge subjected to prolonged anoxic conditions is determined. The total As concentration in the sludge is 300 mg kg-1. In the laboratory, three distinct water cover treatments were imposed on the sludge to induce different redox conditions (100%N2, 100%N2 + glucose, 95%N2:5%H2). These treatments were compared against a control of oxidized, water-saturated sludge. Electron micro-probe (EMP) analysis and spatially resolved synchrotron X-ray fluorescence (SXRF) results indicate that As is dominantly associated with Fe in the sludge. In all treatments and throughout the experiment, measured concentrations of dissolved As were less than 5 μg L-1. Dissolved Mn concentration in the N2 + glucose treatment increased significantly compared to other treatments. Manganese and As K-edge X-ray absorption near edge structure spectroscopy (XANES) analyses showed that Mn was the redox-active element in the solid-phase, while As was stable. Arsenic(V) was still the dominant species in all water-covered sludges after 9 months of anoxic treatments. In contrast, Mn(IV) in the original sludge was partially reduced into Mn(II) in all water-covered sludges. The effect was most pronounced in the N2 + glucose treatment, suggesting microbial reduction. Micro-scale SXRF and XANES analysis of the treated sludge showed that Mn(II) accumulated in areas already enriched in Fe and As. Overall, the study shows that AMD sludges remain stable under prolonged anoxic conditions. External sources of chemical reductants or soluble C were needed to induce lower redox state

  18. Iron(II) supramolecular helicates interfere with the HIV-1 Tat–TAR RNA interaction critical for viral replication

    Malina, Jaroslav; Hannon, Michael J.; Brabec, Viktor

    2016-07-01

    The interaction between the HIV-1 transactivator protein Tat and TAR (transactivation responsive region) RNA, plays a critical role in HIV-1 transcription. Iron(II) supramolecular helicates were evaluated for their in vitro activity to inhibit Tat–TAR RNA interaction using UV melting studies, electrophoretic mobility shift assay, and RNase A footprinting. The results demonstrate that iron(II) supramolecular helicates inhibit Tat-TAR interaction at nanomolar concentrations by binding to TAR RNA. These studies provide a new insight into the biological potential of metallosupramolecular helicates.

  19. Iron(II) supramolecular helicates interfere with the HIV-1 Tat–TAR RNA interaction critical for viral replication

    Malina, Jaroslav; Hannon, Michael J.; Brabec, Viktor

    2016-01-01

    The interaction between the HIV-1 transactivator protein Tat and TAR (transactivation responsive region) RNA, plays a critical role in HIV-1 transcription. Iron(II) supramolecular helicates were evaluated for their in vitro activity to inhibit Tat–TAR RNA interaction using UV melting studies, electrophoretic mobility shift assay, and RNase A footprinting. The results demonstrate that iron(II) supramolecular helicates inhibit Tat-TAR interaction at nanomolar concentrations by binding to TAR RNA. These studies provide a new insight into the biological potential of metallosupramolecular helicates. PMID:27405089

  20. TAR RNA binding properties and relative transactivation activities of human immunodeficiency virus type 1 and 2 Tat proteins.

    Rhim, H; Rice, A P

    1993-01-01

    Using gel shift assays, we found that the human immunodeficiency virus type 1 (HIV-1) Tat protein (Tat-1) bound both HIV-1 and HIV-2 TAR RNAs with similar high affinities. In contrast, the HIV-2 Tat protein (Tat-2) bound only TAR-2 RNA with high affinity. We conclude that the weak in vivo activity of Tat-2 on the HIV-1 long terminal repeat that has been observed previously is likely the result of low affinity for TAR-1 RNA. Additionally, TAR-2 RNA was found to contain multiple specific bindin...