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Sample records for sludge drying plant

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

    Science.gov (United States)

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

    2015-08-01

    Dewatered sewage sludge from Waste Water Treatment Plants (WWTPs) is encountering increasing problems associated with its disposal. Several solutions have been proposed in the last years regarding energy and materials recovery from sewage sludge. Current technological solutions have relevant limits as dewatered sewage sludge is characterized by a high water content (70-75% by weight), even if mechanically treated. A Refuse Derived Fuel (RDF) with good thermal characteristics in terms of Lower Heating Value (LHV) can be obtained if dewatered sludge is further processed, for example by a thermal drying stage. Sewage sludge thermal drying is not sustainable if the power is fed by primary energy sources, but can be appealing if waste heat, recovered from other processes, is used. A suitable integration can be realized between a WWTP and a waste-to-energy (WTE) power plant through the recovery of WTE waste heat as energy source for sewage sludge drying. In this paper, the properties of sewage sludge from three different WWTPs are studied. On the basis of the results obtained, a facility for the integration of sewage sludge drying within a WTE power plant is developed. Furthermore, energy and mass balances are set up in order to evaluate the benefits brought by the described integration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Evaluation of Potentially Harmful Substances in Dried Sludge of Isfahan Wastewater Treatment Plants

    Directory of Open Access Journals (Sweden)

    Bijan Bina

    2004-05-01

    Thus, taking into account the potential risks caused by presence of heavy metals in sludge and for the control of processes of sludge treatment and disposal and also protect of environmental health and enhauncement of public health level, specially for farmers and consumers of raw crops, needs sampling and characterization of sludge. In the present research concentration of 11 heavy metals and potentially toxic elements in dried sludge of Isfahan South and North and Shahinshahr wastewater treatment plants were determined using standard methods. Samples have been taken from dried sludge of treatment plants, and been measured after being prepared through atomic absorption apparatus and were compared with EPA enacted standards in regulation 40 CFR part 503. As well, fertilizer value parameters of sludge were measured and were compared with standards and guidelines. The results showed that the average concentration of above elements in all three treatment plants, not exceeded from EPA standards, however, regarding the accumulative property of these elements and lack of necessary protective effects of EPA standards, in using these sludges in the agricultural soils, the necessary caution and care should be taken, in other uses of sludges, however, there is no limitation.

  3. Use of dry sludge from waste water treatment plants as an additive in prefabricated concrete brick

    Directory of Open Access Journals (Sweden)

    Yagüe, A.

    2002-09-01

    Full Text Available Dry sludge from the Sabadell Water Treatment Plant was used to prepare prefabricated concrete bricks. After characterising the sludge and the manufacturing process used to make the bricks, we define the conditions of addition of the sludges in the manufacture. Reference samples not containing sludge and samples containing 2 % of dry sludge by cement weight were prepared. The variation in density, porosity, absorption coefficient and compressive strength of the bricks with the presence of sludge was determined over time. Leaching of the bricks was determined according to the NEN 7345 standard. In most cases the addition of sludge produces a decrease in porosity and absorption coefficients and an increase in compressive strength, so one could expect these bricks to have greater durability. As regards leaching pollutants in the bricks, they are below the limit of the Dutch NEN standard for construction materials and thus can be classified as inert material.

    El estudio ha consistido en la utilización de lodo seco de origen biológico de la depuradora de aguas residuales de Sabadell (Riu Sec, como adición en la preparación de adoquines de hormigón prefabricado. Después de caracterizar los lodos y el proceso de fabricación de los adoquines que utilizaremos, definimos las condiciones de adición de los lodos en esta fabricación. Se prepararon muestras de referencia, sin adición, y muestras con el 2 % de lodo seco sobrepeso de cemento. Se determinaron cómo variaban en el tiempo, con la presencia de lodos: la densidad, la porosidad y el coeficiente de absorción, y la resistencia mecánica a compresión de los adoquines. También se determinó la lixiviación que estas piezas presentaban de acuerdo a la norma NEN 7345. La adición de lodos produce, en la mayoría de los casos, una disminución de las porosidades y de los coeficientes de absorción y un aumento en las resistencias mecánicas, por lo que cabe esperar una mayor

  4. Fluidization of Dried Wastewater Sludge.

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Pohořelý, Michael; Trnka, Otakar

    2007-01-01

    Roč. 178, 3 (2007) , s. 166-172 ISSN 0032-5910 R&D Projects: GA AV ČR(CZ) IAA4072201 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidization characteristics * multiphase reactors * dried stabilized wastewater sludge Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.130, year: 2007

  5. Anaerobic Treatment Of Percolate From Faecal Sludge Drying Beds ...

    African Journals Online (AJOL)

    Composite percolate samples, from sludge drying beds of a pilot co-composting plant in Kumasi, Ghana, were characterised and subjected to laboratory scale anaerobic treatment. Two categories of percolate samples were investigated; samples seeded with anaerobic sludge and samples without seeding. The average ...

  6. Dewaterability of sludge digested in extended aeration plants using ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-07-19

    Jul 19, 2010 ... Dewaterability of unconditioned sludge digested in full scale and lab scale experiments using either extended aeration (EA) or anaerobic digestion were compared on full and lab scale sand drying beds. Sludge digested in EA plants resulted in improvement in sludge dewaterability compared to sludge.

  7. Dewaterability of sludge digested in extended aeration plants using ...

    African Journals Online (AJOL)

    Dewaterability of unconditioned sludge digested in full scale and lab scale experiments using either extended aeration (EA) or anaerobic digestion were compared on full and lab scale sand drying beds. Sludge digested in EA plants resulted in improvement in sludge dewaterability compared to sludge digested ...

  8. Evaluation of gaseous emissions produced in the tests on the demonstration plant for sludge drying and incineration

    International Nuclear Information System (INIS)

    Lotito, V.; Spinosa, L.; Antonacci, R.; Mininni, G.

    2001-01-01

    Incineration is a valid alternative to other more diffused disposal systems (agricultural use, landfill), when they cannot be applied due to high pollutants concentrations or other unforeseeable constraints. However, it can cause severe air pollution by inorganic (heavy metals) and organic (PAHs, PCDDs, PCDFs) pollutants, particulate, NO x , CO and acidic compounds; this fact has raised public concern about incineration and has hindered a wider application of this practice. Water Research Institute of Italian National Research Council realised a demonstration plant mainly consisting of a fluidized bed furnace, a rotary kiln furnace, a dryer with heat recovery section, particulate and acidic compounds removal apparatuses, and set up a research programme to demonstrate that incineration is a safe operation and can comply the relevant legislation, as far as organic and inorganic micropollutants are concerned. A total of 40 tests were carried out (30 with the fluidized bed furnace and 10 with rotary kiln one) treating dewatered sludges (in many cases with the addition of high chlorinated compounds and Cu salts) or dried ones, under different operating conditions (furnace temperature, after-burner temperature, chlorine concentration). Particulate concentrations, and consequently heavy metals concentrations, at the stack resulted in any case under legal limits. As far as conventional pollutants are concerned, only HCl and CO overcame sometimes standards, mainly due to temporary operating up-sets. PAHs concentration resulted quite constant, thus demonstrating that tests were operated in steady-state and satisfactory conditions. Also dioxins and furans overcame sometimes standards, but no correlation was found with more severe tests conditions; it happened when plant up-set conditions occurred. Operation resulted quite satisfactory, but dryer operation required constant operators attention. In rotary kiln furnace a build up of solidified ashes occurred in counter

  9. The exploitation of swamp plants for dewatering liquid sewage sludge

    Directory of Open Access Journals (Sweden)

    Jiří Šálek

    2006-01-01

    Full Text Available The operators of little rural wastewater treatment plants have been interested in economic exploitation of sewage sludge in local conditions. The chance is searching simply and natural ways of processing and exploitation stabilized sewage sludge in agriculture. Manure substrate have been obtained by composting waterless sewage sludge including rest plant biomass after closing 6–8 years period of filling liquid sewage sludge to the basin. Main attention was focused on exploitation of swamp plants for dewatering liquid sewage sludge and determination of influence sewage sludge on plants, intensity and course of evapotranspiration and design and setting of drying beds. On the base of determined ability of swamp plants evapotranspiration were edited suggestion solutions of design and operation sludge bed facilities in the conditions of small rural wastewater treatment plant.

  10. Energy from biomass: Wood-fuelled sewage sludge drying plant; Energetische Nutzung von Biomasse am Beispiel einer holzbefeuerten Klaerschlammtrocknungsanlage. Planung, Bau und erste Betriebserfahrung

    Energy Technology Data Exchange (ETDEWEB)

    Burgtorf, J. [Saarberg-Oekotechnik GmbH, Saarbruecken (Germany)

    1998-09-01

    A unique concept was developed for the drying plant of Biowaerme-Braeunlingen GmbH (BWB): The heat for drying sewage sludge is generated by a wood chip furnace with staggered grate, and the waste heat from plume condensation is fed into a district heating system supplying a neighbouring commercial and trade center. (orig./SR) [Deutsch] Fuer die Trocknungsanlage der Biowaerme-Braeunlingen GmbH (BWB) wurde ein bisher einmaliges Konzept entwickelt: Die zur Trocknung der kommunalen Klaerschlaemme des Kreises erforderliche Waerme wird durch ein Holzhackschnitzelheizwerk mit Treppenrostfeuerung erzeugt und die bei der Kondensation der Brueden anfallende Abwaerme wird in einem Fernwaermenetz zur Versorgung des umliegenden Gewerbegebietes genutzt. (orig./SR)

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

    International Nuclear Information System (INIS)

    Ohm, Tae-In; Chae, Jong-Seong; Kim, Jeong-Eun; Kim, Hee-kyum; Moon, Seung-Hyun

    2009-01-01

    In sludge treatment, drying sludge using typical technology with high water content to a water content of approximately 10% is always difficult because of adhesive characteristics of sludge. Many methods have been applied, including direct and indirect heat drying, but these approaches of reducing water content to below 40% after drying is very inefficient in energy utilization of drying sludge. In this study, fry-drying technology with a high heat transfer coefficient of approximately 500 W/m 2 deg. C was used to dry industrial wastewater sludge. Also waste oil was used in the fry-drying process, and because the oil's boiling point is between 240 and 340 deg. C and the specific heat is approximately 60% of that of water. In the fry-drying system, the sludge is input by molding it into a designated form after heating the waste oil at temperatures between 120 and 170 deg. C. At these temperatures, the heated oil rapidly evaporates the water contained in the sludge, leaving the oil itself. After approximately 10 min, the water content of the sludge was less than 10%, and its heating value surpassed 5300 kcal/kg. Indeed, this makes the organic sludge appropriate for use as a solid fuel. The wastewater sludge used in this study was the designated waste discharged from chemical, leather and plating plants. These samples varied in characteristics, especially with regard to heavy metal concentration. After drying the three kinds of wastewater sludge at oil temperatures 160 deg. C for 10 min, it was found that the water content in the sludge from the chemical, leather, and plating plants reduced from 80.0 to 5.5%, 81.6 to 1.0%, and 65.4 to 0.8%, respectively. Furthermore, the heat values of the sludge from the chemical, leather, and plating plants prior to fry-drying were 217, 264, and 428 kcal/kg, respectively. After drying, these values of sludge increased to 5317, 5983 and 6031 kcal/kg, respectively. The heavy metals detected in the sludge after drying were aluminum

  12. Costs and economic efficiency of the drying of sewage sludges; Kosten und Wirtschaftlichkeit der Klaerschlammtrocknung

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Ulrich [Haarslev Industries A/S, Herlev (Denmark). Marketing and Business Development

    2013-03-01

    New methods of the thermal utilization have to be created due to the fact that agricultural utilisation of sewage sludge and the use in the reclamation due to stringent limit values and enhanced quality criteria are available restricted in future. The incineration of mechanically dewatered and dried sewage sludge is performed in mono-combustion plants as well as in coal-fired power plants. The author of the contribution under consideration reports on the costs and economic efficiency of the drying of sewage sludge. The drying of sewage sludge may perform an important and reasonable contribution to the utilization of municipal sewage sludge. The selection of a suitable drying process should ever depend on the local realities. Proved and suitable technologies are available for every application. Before the decision for a certain provider, one should examine reference plants and consider specific experiences of the operator among the decision-making.

  13. [Effects of ultrasonic pretreatment on drying characteristics of sewage sludge].

    Science.gov (United States)

    Li, Run-Dong; Yang, Yu-Ting; Li, Yan-Long; Niu, Hui-Chang; Wei, Li-Hong; Sun, Yang; Ke, Xin

    2009-11-01

    The high water content of sewage sludge has engendered many inconveniences to its treatment and disposal. While ultrasonic takes on unique advantages on the sludge drying because of its high ultrasonic power, mighty penetrating capability and the ability of causing cavitations. Thus this research studies the characteristics influences of ultrasonic bring to the sludge drying and effects of the exposure time, ultrasonic generator power, temperatures of ultrasonic and drying temperature on the drying characteristics of dewatered sludge. Results indicate that ultrasonic pretreatment could speed up evaporation of the free water in sludge surface and help to end the drying stage with constant speed. In addition, ultrasonic treatment can effectively improve the sludge drying efficiency which could be more evident with the rise of the ultrasonic power (100-250 W), ultrasonic temperature and drying temperature. If dried under low temperature such as 105 degrees C, sludge will have premium drying characteristics when radiated under ultrasound for a shorter time such as 3 min. In the end, the ultrasonic treatment is expected to be an effective way to the low-cost sludge drying and also be an important reference to the optimization of the sludge drying process because of its effects on the increase of sludge drying efficiency.

  14. Modeling of Seepage Losses in Sewage Sludge Drying Bed ...

    African Journals Online (AJOL)

    This research was carried out to develop a model governing seepage losses in sewage sludge drying bed. The model will assist in the design of sludge drying beds for effective management of wastes derived from households' septic systems. In the experiment conducted this study, 125kg of sewage sludge, 90.7% moisture ...

  15. Accelerating Aerobic Sludge Granulation by Adding Dry Sewage Sludge Micropowder in Sequencing Batch Reactors

    Science.gov (United States)

    Li, Jun; Liu, Jun; Wang, Danjun; Chen, Tao; Ma, Ting; Wang, Zhihong; Zhuo, Weilong

    2015-01-01

    Micropowder (20–250 µm) made from ground dry waste sludge from a municipal sewage treatment plant was added in a sequencing batch reactor (R2), which was fed by synthetic wastewater with acetate as carbon source. Compared with the traditional SBR (R1), aerobic sludge granulation time was shortened 15 days in R2. Furthermore, filamentous bacteria in bulking sludge were controlled to accelerate aerobic granulation and form large granules. Correspondingly, the SVI decreased from 225 mL/g to 37 mL/g. X-ray Fluorescence (XRF) analysis demonstrated that Al and Si from the micropowder were accumulated in granules. A mechanism hypotheses for the acceleration of aerobic granulation by adding dry sludge micropowder is proposed: added micropowder acts as nuclei to induce bacterial attachment; dissolved matters from the micropowder increase abruptly the organic load for starved sludge to control overgrown filamentous bacteria as a framework for aggregation; increased friction from the movement of micropowder forces the filaments which extend outwards to shrink for shaping granules. PMID:26308025

  16. Municipal Sewage Sludge Drying Treatment by an Composite Modifier

    OpenAIRE

    Na Wei

    2012-01-01

    A sludge composite modifier (SCM) which comprises a mixture of three cementitious components was proposed for sludge drying and stabilization. Effect of SCM components on sludge moisture content was analyzed using uniform design and the optimum composition of SCM was determined by computer-aided modeling and optimization. To compare the drying effect of SCM, quicklime, and Portland cement, the effects of material content and curing time on moisture content of sludge were also studied. The res...

  17. Relationship between centrifugation and drying of sludge and the organic halogens

    Directory of Open Access Journals (Sweden)

    Karel Hrich

    2010-01-01

    Full Text Available This work is focused on determination of adsorbable organic halogens (AOX concentration in the digested sludge from the sewage treatment plant and the losses of this component during dewatering and drying of sludge. Drying of the sludge from wastewater treatment plant is not extended too much in Czech Republic. In this work, the AOX are monitored, because AOX is one of the limits restraining use of the sludge on an agricultural land. Another reason is technological demand for using the sludge in cement processing, because chlorine in AOX can cause decrease in a heat transfer effect in a cement kiln. It is clear from the results that both centrifuged and dried sludge from the sewage treatment plant Brno fulfilled limits for using sludge on agriculture land. They can also be composted, in case they meet other requirements. If not, it is a possibility of co-incineration in cement kiln. In such case, limit for total chlorine including the AOX is required too. This limit was not exceeded. Another aim was to calculate a mass balance of AOX during the centrifugation and drying processes. It was found out, that after centrifugation the main part of AOX remained in the centrifuged sludge (96.4 %. The rest was drawn-off with reject water. 60 % of AOX in the reject water were dissolved compounds. A similar situation occurred during the drying process. More than 99 % of AOX was bound in the dried sludge. The air and vaporised water contained such quantity of AOX, which corresponded with the amount of the dust in the air and the amount of particles of sludge in vaporised water.

  18. Sludge derived fuel technique of sewage sludge by oil vacuum evaporation drying

    International Nuclear Information System (INIS)

    Kim, Seokhwan; Lim, Byungran; Lee, Sookoo

    2010-01-01

    Sewage sludge contains high content of organic materials and its water content is also very high about 80% even after filtration process. Landfill as a sludge treatment methods can cause odor problem and leachate production which can derive the secondary contamination of soil and groundwater. The ocean dumping will be prohibited according to the London Convention and domestic stringent environmental regulation. Based on domestic agenda on organic sewage sludge treatment, the ocean disposal will be prohibited from 2012, thus alternative methods are demanded. Sludge derived fuel (SDF) technology can alleviate the emission of greenhouse gas and recover energy from sludge. For proper treatment and SDF production from sludge, the vacuum evaporation and immersion frying technology was adopted in this research. This technology dries moisture in sludge after mixing with oil such as Bunker C oil, waste oil or waste food oil etc. Mixing sludge and oil secures liquidity of organic sludge to facilitate handling throughout the drying process. The boiling temperature could be maintained low through vacuum condition in whole evaporation process. This study was performed to find the optimum operating temperature and pressure, the mixing ratio of sludge and oil. Finally, we could obtained SDF which moisture content was less than 5%, its heating value was over 4,500 kcal/ kg sludge. This heating value could satisfy the Korean Fuel Standard for the Recycle Products. Assessed from the perspective of energy balance and economic evaluation, this sludge drying system could be widely used for the effective sludge treatment and the production of SDF. (author)

  19. Effects of thermal drying on phosphorus availability from iron-precipitated sewage sludge

    DEFF Research Database (Denmark)

    Lemming, Camilla; Scheutz, Charlotte; Bruun, Sander

    2017-01-01

    sludge, and a triple superphosphate as a reference. Plant P availability was studied in a 197 d soil incubation experiment, with sampling for Diffusive Gradients in Thin films (DGT) and water extractable P (WEP) analyses over time, and in a pot experiment with spring barley (Hordeum vulgare L.). In both......, affects plant P availability after application to soil. The experiment included dewatered sewage sludge (20% DM) and thermally dried sewage sludge (95% DM) collected at a Danish wastewater treatment plant, as well as laboratory oven-dried (70, 130, 190, and 250°C; DM > 95%) subsamples of the dewatered...... experiments, thermal drying reduced P availability, as shown by 37 and 23% lower DGT and WEP values, respectively, and a 16% lower P uptake by barley in the pot experiment. The specific drying temperature did not appear to have much effect. Overall, our results suggest that thermal drying of iron...

  20. Changes on sewage sludge stability after greenhouse drying

    Science.gov (United States)

    Soriano-Disla, J. M.; Houot, S.; Imhoff, M.; Valentin, N.; Gómez, I.; Navarro-Pedreño, J.

    2009-04-01

    The progressive implementation of the Urban Waste Water Treatment Directive 91/271/EEC in all the European member states is increasing the quantities of sewage sludge requiring disposal. Sludge application onto cultivated soils as organic fertilizers allows the recycling of nutrients. The application of only dehydrated sludges has generated many problems including unpleasant odours and difficult management (regarding transport and application) related to their high water content. One way to overcome these problems, in a cheap and clean way, is the drying of sludges using the energy of the sun under greenhouse conditions. This drying may affect sludge chemical characteristics including organic matter stability and nitrogen availability, parameters which have to be controlled for the proper management of dry sludge application onto soils. For this reason, the main aim of this work was to study the impact of greenhouse drying of different sewage sludges on their organic matter stability and nitrogen availability, assessed by biochemical fractionation and mineralization assays. Three sewage sludges were sampled before (dehydrated sludges) and after greenhouse drying (dried sludges). The analyses consisted of: humidity, organic matter, mineral and organic N contents, N and C mineralization during 91-day laboratory incubations in controlled conditions, and biochemical fractionation using the Van Soest procedure. Greenhouse drying decreased the water content from 70-80% to 10% and also the odours, both of which will improve the management of the final product from the perspective of application and transport. We also found that drying reduced the organic matter content of the sludges but not the biodegradability of the remaining carbon. Organic N mineralization occurred during greenhouse drying, explaining why mineral N content tended to increase and the potential mineralization of organic nitrogen decreased after greenhouse drying. The biochemical stability did not

  1. Impact of storage duration on the gaseous emissions during convective drying of urban residual sludges

    Energy Technology Data Exchange (ETDEWEB)

    Fraikin, L.; Salmon, T.; Crine, M.; Leonard, A. [University of Liege, Laboratory of Chemical Engineering, Liege (Belgium); Herbreteau, B.; Nicol, F. [VEOLIA Environnement Recherche et Innovation, Limay (France); Levasseur, J.P. [VEOLIA Water, Technical Direction, Saint-Maurice (France)

    2011-07-15

    Drying has become an important step within the context of sludge management. Sometimes, sludges from several wastewater treatment plants are centralized in order to dry them at an acceptable cost. Depending on sludge supply, there can be a delay between delivery and feeding into the dryer. The impact of sludge storage duration on the drying kinetics and on the exhaust emissions of volatile organic compounds (VOCs), and ammonia is investigated. Results show that, after 20 days of storage, the drying time is multiplied by 1.5, and the emissions of VOCs and NH{sub 3} are multiplied by 5 and 40, respectively. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Demonstration of the vacuum drying technique on sludge from the paper and pulp industry; Demonstration av vakuumtorktekniken paa skogsindustriellt slam

    Energy Technology Data Exchange (ETDEWEB)

    Eklund, Anders [AaF-Energikonsult AB, Stockholm (Sweden)

    2003-10-01

    Previous studies have indicated that a cost effective drying of sludge from the paper and pulp mills can be done by the use of vacuum at a lower water temperature. The purpose was to erect a pilot plant and test different types of sludge. Therefore, advantages and problems with this method could be determined. This work has planned and erected a complete pilot plant for continuous drying of sludge and the pilot plant occupies a hard surface of 10x10 meters. A drum type dryer is in the centre of the pilot plant and it has been modified for lower pressures. Other vital components are: handling of vapours, vacuum pump, hot water generation and materials handling of the sludge, both in wet and dry condition. First, tests where carried out to verify theories and previous laboratory studies. These test successfully confirmed that difficult sludge types could effectively be dried at lower temperatures by the use of vacuum. Then, tests where carried out on 9 different sludges from 7 different mills. Average sample weight was about 170 kg or 250 litres. All sludge samples could successfully be dried but with different levels of complexity. For an easier comprehension of the handling and drying, the different sludges were organised into three classes: sludge with a clear resemblance of clay, sludge with a resemblance of mud or earth and finally, sludge with a majority of fibres. Fibre type sludges were easy to dry to a high degree of dryness. However, they also dusted easily and thus, fibres easily carried over into the condensate. Earth type sludge was in wet condition difficult to handle. The drying was more time consuming and the sludge formed small round balls during the drying. These balls slowed the drying process but they were eventually gradually reduced and a higher degree of drying could continue. Clay type sludges formed already in the handling round balls and during drying these balls formed a hard dry outer layer, which contained moisture inside the balls. By

  3. Modeling of Evaporation Losses in Sewage Sludge Drying Bed ...

    African Journals Online (AJOL)

    A model for evaporation losses in sewage sludge drying bed was derived from first principles. This model was developed based on the reasoning that the rate at which evaporation is taking place is directly proportional to the instantaneous quantity of water in the sludge. The aim of this work was to develop a model to assist ...

  4. Vendor Testing of Sensitive Compounds in Simulated Dry Sludge

    International Nuclear Information System (INIS)

    Dworjanyn, L.O.

    1999-01-01

    This assessment covers thermal screening, differential scanning calorimetry, and impact sensitivity testing on Mercury Fulminate, and mixtures of the fulminate in dry inorganic sludge, which is present in large quantities in a number of storage tanks at Westinghouse Savannah River

  5. Fluid dynamics simulation for design on sludge drying equipment

    Science.gov (United States)

    Li, Shuiping; Liang, Wang; Kai, Zhang

    2017-10-01

    Sludge drying equipment is a key component in the sludge drying disposal, the structure of drying equipment directly affects the drying disposal of the sludge, so it is necessary to analyse the performance of the drying equipment with different structure. Fluent software can be very convenient to get the distribution of the flow field and temperature field inside the drying equipment which reflects the performance of the structure. In this paper, the outlet position of the sludge and the shape of the sludge inlet are designed. The geometrical model of the drying equipment is established by using pre-processing software Gambit, and the meshing of the model is carried out. The Eulerian model is used to simulate the flow of each phase and the interaction between them, and the realizable turbulence model is used to simulate the turbulence of each phase. Finally, the simulation results of the scheme are compared and the optimal structure scheme is obtained, the operational requirement is proposed. The CFD theory provides a reliable basis for the drying equipment research and reduces the time and costs of the research.

  6. Municipal Sewage Sludge Drying Treatment by an Composite Modifier

    Directory of Open Access Journals (Sweden)

    Na Wei

    2012-01-01

    Full Text Available A sludge composite modifier (SCM which comprises a mixture of three cementitious components was proposed for sludge drying and stabilization. Effect of SCM components on sludge moisture content was analyzed using uniform design and the optimum composition of SCM was determined by computer-aided modeling and optimization. To compare the drying effect of SCM, quicklime, and Portland cement, the effects of material content and curing time on moisture content of sludge were also studied. The results showed that the optimum ratio of modifier component was slag/cement clinker/dihydrate gypsum = 0.64/0.292/0.068 and the moisture content of SCM-stabilized sludge decreased with the increasing material content and extending curing time. Besides, the experimental results showed that optimized SCM behaved better than quicklime and Portland cement in sludge semi-drying and XRD analysis revealed that the main hydrated product of stabilization was ettringite, which played an important role in the effective drying process. Sewage sludge stabilized using SCM could be used as an effective landfill cover.

  7. Bacterial regrowth potential in alkaline sludges from open-sun and covered sludge drying beds

    Energy Technology Data Exchange (ETDEWEB)

    Alkan, U.; Topac, F.O.; Birden, B.; Baskaya, H.S. [Uludag University, Gorukle (Turkey). Dept. of Environmnetal Engineering

    2007-10-15

    The aim of this study was to compare the regrowth potentials of wastewater sludges dried in two pilot-scale drying processes namely, Open-Sun Sludge Drying Bed (OSDB) and Covered Sludge Drying Bed (CSDB). Quicklime and/or coal fly ash were added to raw sludge samples prior to drying processes in order to enhance bacterial inactivation. Following three drying cycles (March-April, June-July and August-October), sludge samples were taken from the beds for the regrowth experiments. Addition of alkaline materials prevented the regrowth of faecal coliforms in all rewetted samples except for the samples obtained after the rainfall events in OSDB. Rewetting of these samples in the regrowth experiments increased faecal coliform numbers by 3.5-7 log units. In contradiction, the observed bacterial numbers in rewetted alkaline samples from CSDB were below the EPA Class B criterion (2 million MPN g{center_dot} 1) dry sludge). The combination of additional heat from solar collectors, protection from the rain and the unfavourable living conditions owing to alkaline materials appeared to inactivate bacteria more effectively in CSDB and hence eliminated regrowth potential more efficiently.

  8. Improved compaction of dried tannery wastewater sludge.

    Science.gov (United States)

    Della Zassa, M; Zerlottin, M; Refosco, D; Santomaso, A C; Canu, P

    2015-12-01

    We quantitatively studied the advantages of improving the compaction of a powder waste by several techniques, including its pelletization. The goal is increasing the mass storage capacity in a given storage volume, and reducing the permeability of air and moisture, that may trigger exothermic spontaneous reactions in organic waste, particularly as powders. The study is based on dried sludges from a wastewater treatment, mainly from tanneries, but the indications are valid and useful for any waste in the form of powder, suitable to pelletization. Measurements of bulk density have been carried out at the industrial and laboratory scale, using different packing procedures, amenable to industrial processes. Waste as powder, pellets and their mixtures have been considered. The bulk density of waste as powder increases from 0.64 t/m(3) (simply poured) to 0.74 t/m(3) (tapped) and finally to 0.82 t/m(3) by a suitable, yet simple, packing procedure that we called dispersion filling, with a net gain of 28% in the compaction by simply modifying the collection procedure. Pelletization increases compaction by definition, but the packing of pellets is relatively coarse. Some increase in bulk density of pellets can be achieved by tapping; vibration and dispersion filling are not efficient with pellets. Mixtures of powder and pellets is the optimal packing policy. The best compaction result was achieved by controlled vibration of a 30/70 wt% mixture of powders and pellets, leading to a final bulk density of 1t/m(3), i.e. an improvement of compaction by more than 54% with respect to simply poured powders, but also larger than 35% compared to just pellets. That means increasing the mass storage capacity by a factor of 1.56. Interestingly, vibration can be the most or the least effective procedure to improve compaction of mixtures, depending on characteristics of vibration. The optimal packing (30/70 wt% powders/pellets) proved to effectively mitigate the onset of smouldering

  9. Investigation of Excess Sludge Generated from Activated Sludge Treatment Plant of Concentrated Latex Factories: An Investigative Case Study in Southern Thailand

    Directory of Open Access Journals (Sweden)

    Wanrudee Wanseng

    2017-06-01

    Full Text Available Activated sludge technology has been employed for wastewater treatment in the concentrated latex factories in the south of Thailand. This paper highlights the survey results of the excess sludge generated from activated sludge treatment plants of the concentrated latex factories, including sludge generation rate, sludge characteristics, as well as sludge management and its problems. The total number of 11 factories was investigated. The findings showed that 20% of the investigated factories using activated sludge did not know how much the excess sludge generation rate was. With an in-depth investigation, the excess sludge generation rate was determined as for 28 kg/ton concentrated latex product or 10 kg/ton of field latex used in the concentrated latex factories. The excess sludge had a low C/N ratio with an average value of 4.7 and contained N, P, and K with the average of percentage values of 8.0, 2.0, and 1.0% dry basis, respectively. However, the excess sludge consisted of Zn with an average of 3.01% dry basis. 60% of the investigated factories using an activated sludge system had issues concerning the management of excess sludge. Moreover, various aspects of the excess sludge management were discussed and lessons were learned on the current excess sludge management of the concentrated latex industry in the south of Thailand.

  10. Recycling of sewage sludge: Feeding Nile tilapia, Oreochromis niloticus (Linn.), with irradiated and dried sludge from beer industry

    International Nuclear Information System (INIS)

    Chuapoehuk, W.; Piadang, S.; Tinnungwattana, W.

    1998-01-01

    Recycling of sewage sludge from wastewater treatment plant of beer industry as supplemental feed for fish was conducted. Industrial biosludge from wastewater treatment plant of beer industry was irradiated at 3.32 kGy gamma irradiator, carrier type, model JS 8900, 60 Co activity at 187,088.121 Ci on 6 June 1995. For fish production study, it is needed to change the wet sludge to dry powder form by Rotadics dryer, type Stord TST 3.4 C, Stord (Thailand) Co. Ltd., at the maximum capacity of 15 T/24 h. The moisture content of finished product is at 8-10%. Fish control diet was then replaced at 60% by weight with irradiated and dried sludge to become as test diet. Nile tilapia, Oreochromis niloticus (Linn.), fingerlings averaging 0.67 g. in body weight was stocked into earthern ponds of 400 square meters at the density of 5 fishes per square metre. Fish were fed with two diets, control diet and test diet, for 154 days. There are no statistical differences in specific growth rate, quality of the fish flesh (Cd and Pb concentration, edible portion and off flavour) and pond water quality. Survival rate and feed conversion efficiency of the fish fed test diet are higher than control diet (P<0.05). Replacement of irradiated sludge can decrease the cost of fish production and results in better benefit than that of control diet

  11. The drying of sewage sludge by immersion frying

    Directory of Open Access Journals (Sweden)

    D. P. Silva

    2005-06-01

    Full Text Available The objective of this work was to dry sewage sludge using a fry-drying process. The frying experiments were carried out in commercial fryers modified by adding thermocouples to the setup. During frying, typical drying curves were obtained and it was verified that, in relation to the parameters: oil temperature, oil type and shape of the sample, the shape factor the most effect on the drying rate, at least within the range chosen for the variables studied. Oil uptake and calorific value were also analyzed. The calorific value of the samples increased with frying time, reaching values around 24MJ/kg after 600s of frying (comparable to biocombustibles such as wood and sugarcane bagasse. The process of immersion frying showed great potential for drying materials, especially sewage sludge, obtaining a product with a high energy content, thereby increasing its value as a combustible.

  12. Environmental considerations on the FBC combustion of dry sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M. Helena; Abelha, Pedro; Gulyurtlu, Ibrahim; Cabrita, Isabel [INETI/DEECA, Lisboa (Portugal)

    2001-07-01

    This paper presents results of on-going research on the incineration of pre-dried granular sewage sludges using a FBC system. Co-combustion is compared with mono-combustion of sludges leads to minor emissions and higher retention of Cd, Pb, Cu, and Zn in the bottom ashes, when compared to co-combustion with coal. The leachability of the sludge is reduced through combustion, as none of the metals, Cd, Cr, Ca Ni, Ph, Zn, Co and Mn were leached from the bottom ashes. These findings may contribute to an improvement in the incineration of sewage sludges and to the development of applications for the ashes in civil engineering activities.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Drying behavior of K-East canister sludge

    International Nuclear Information System (INIS)

    Abrefah, J.; Buchanan, H.C.; Marschman, S.C.

    1998-05-01

    A series of tests were conducted by Pacific Northwest National Laboratory to evaluate the drying behavior of sludge taken from the Hanford K-East Basin storage canisters. Some of the components of K-Basin sludge, such as oxides of uranium and its hydrates, could be associated with the spent nuclear fuel that will ultimately be loaded into Multi-Canister Overpacks (MCOs) and transferred to interim dry storage on the Hanford Site. The materials sealed in the MCOs must be compatible with the storage facility safety basis and the design accident analyses. Understanding the drying behavior of hydrates that may be formed by the reaction of uranium oxides (corrosion products) and water will help ensure these criteria are addressed. Drying measurements of sludge samples collected from K-East Basin canisters showed the water content (physically plus chemically bound) to range between 5 wt% and 75 wt%. Uranium oxide hydrates, the main source of gaseous products that can pressurize the MCOs during storage, constituted about 3 wt% to 15 wt% of the total water content of the initial weight. Most of the physically bound water was assumed to be released from the samples at ambient temperature when the system was pumped down to vacuum conditions of about 40 mTorr. The period for release of most free water in the K-East canister sludge was about 24 hours

  15. Heavy metal fate in pilot-scale sludge drying reed beds under various design and operation conditions.

    Science.gov (United States)

    Stefanakis, Alexandros I; Tsihrintzis, Vassilios A

    2012-04-30

    Thirteen pilot-scale sludge drying reed bed (SDRB) units have been constructed and operated under various settings. The beds included a cobbles lower layer, where perforated PVC aeration tubes were placed, and two gravel layers on top. The setup included planted beds with common reeds and control units. Three sludge loading rates (SLR) were examined: 30, 60 and 75 kg dm/m(2)/yr. Heavy metal (HM) accumulation in the residual sludge layer was negligible or low, and was found to increase with sludge layer depth. Plant uptake was low; the belowground biomass accumulated significantly more HMs compared to the aboveground biomass. Less than 16% of the influent HM left the bed through drainage. HM accumulation in the gravel layer was the major metal sink in the mass balance. On the whole, the HM content of the residual sludge was below the legal limits proposed by the EU for land application. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Independent Panel Evaluation of Dry Sludge PISA Program

    International Nuclear Information System (INIS)

    Fondeur, F.F.

    1999-01-01

    Dr. Kirk Yeager and Mr. Marvin Banks from Energetic Material Research and Technology Center (EMRTC) evaluated the Savannah River Site (SRS) efforts in the Dry Sludge program. They evaluated four program areas: energetic material formation, stability, initiation, and propagation. The panel evaluation included a site visit (July 13, 1999 and July 14, 1999) as well as a review of various reports and presentations by researchers involved in the program

  17. Independent Panel Evaluation of Dry Sludge PISA Program

    Energy Technology Data Exchange (ETDEWEB)

    Fondeur, F.F.

    1999-10-20

    Dr. Kirk Yeager and Mr. Marvin Banks from Energetic Material Research and Technology Center (EMRTC) evaluated the Savannah River Site (SRS) efforts in the Dry Sludge program. They evaluated four program areas: energetic material formation, stability, initiation, and propagation. The panel evaluation included a site visit (July 13, 1999 and July 14, 1999) as well as a review of various reports and presentations by researchers involved in the program.

  18. Technical and economical feasibility study of a sewage sludge disinfection plants by irradiation process

    International Nuclear Information System (INIS)

    Rojas Bustos, Gustavo

    1999-01-01

    This report presents a technical and economical evaluation for a disinfection plant of sewage sludge based on irradiation. The process starts after sludge stabilization which is achieved by anaerobic digestion. It includes two stages, plus an optional: the first corresponds to dewatering of sewage sludge up to a solids content between 20 and 25 %, the second stage corresponds to disinfection by gamma or electron beam irradiation, and the third, which is optional, corresponds to the drying of sewage sludge up to a water content of 50%, which allows to diminish significantly the volumes of solids to be transported. If this stage is not accomplished the final product corresponds to a sewage sludge with 25 % of dry solids, which can also be disposed in agricultural land. Process was designed to treat 60 tons per day of sewage sludge (dry matter basis). The report presents the design of process equipment, principal and auxiliary, the investment and operational cost estimations as well as the total cost of treatment per ton of sewage sludge. A sensitivity analysis is also included to determine the influence of operational process parameters in operational and investment costs. The results showed that a sewage sludge plant including dewatering and disinfection process through gamma irradiation, achieves a capital investment of about US$ 12.000.000 with a treatment cost per ton of dry sludge of US$140. Including the optional air-drying stage, the total cost of treatment is about US$148 per ton of dry matter. In the case of electron beam irradiation the capital investment achieves a value of US$ 11 millions with a total treatment cost of US$ 136 per ton of dry matter. These values resulted quite similar to the cost of alternative treatment, i.e., disposal in a dedicated landfill. (L.V.)

  19. Energy potential and alternative usages of biogas and sludge from UASB reactors: case study of the Laboreaux wastewater treatment plant.

    Science.gov (United States)

    Rosa, A P; Conesa, J A; Fullana, A; Melo, G C B; Borges, J M; Chernicharo, C A L

    2016-01-01

    This work assessed the energy potential and alternative usages of biogas and sludge generated in upflow anaerobic sludge blanket reactors at the Laboreaux sewage treatment plant (STP), Brazil. Two scenarios were considered: (i) priority use of biogas for the thermal drying of dehydrated sludge and the use of the excess biogas for electricity generation in an ICE (internal combustion engine); and (ii) priority use of biogas for electricity generation and the use of the heat of the engine exhaust gases for the thermal drying of the sludge. Scenario 1 showed that the electricity generated is able to supply 22.2% of the STP power demand, but the thermal drying process enables a greater reduction or even elimination of the final volume of sludge to be disposed. In Scenario 2, the electricity generated is able to supply 57.6% of the STP power demand; however, the heat in the exhaust gases is not enough to dry the total amount of dehydrated sludge.

  20. Plant uptake of pentachlorophenol from sludge-amended soils

    International Nuclear Information System (INIS)

    Bellin, C.A.; O'Connor, G.A.

    1990-01-01

    A greenhouse study was conducted to determine the effects of sludge on plant uptake of 14 C-pentachlorophenol (PCP). Plants included tall fescue (Festuca arundinacea Schreb.), lettuce (Latuca sativa L.), carrot (Daucus carota L.), and chile pepper (Capsicum annum L.). Minimal intact PCP was detected in the fescue and lettuce by gas chromatography/mass spectrometry (GC/MS) analysis. No intact PCP was detected in the carrot tissue extracts. Chile pepper was not analyzed for intact PCP because methylene chloride extracts contained minimal 14 C. The GC/MS analysis of soil extracts at harvest suggests a half-life of PCP of about 10 d independent of sludge rate or PCP loading rate. Rapid degradation of PCP in the soil apparently limited PCP availability to the plant. Bioconcentration factors (dry plant wt./initial soil PCP concentration) based on intact PCP were < 0.01 for all crops, suggesting little PCP uptake. Thus, food-chain crop PCP uptake in these alkaline soils should not limit land application of sludge

  1. Liquid state bioconversion of sewage treatment plant sludge in batch fermenter and shake flask.

    Science.gov (United States)

    Alam, Md Zahangir; Fakhru'l-Razi, A

    2004-01-01

    A study on liquid state bioconversion of sewage treatment plant (STP) sludge was assisted to evaluate the performance of batch fermenter compared to shake flask in a laboratory. Bioconversion of STP sludge was highly influenced by the mixed fungal culture of Penicillium corylophilum and Aspergillus niger after 4 days of treatment. The results showed that about 24.9 g kg(-1) dry sludge cake (DSC) was produced with enrichment of fungal biomass protein in fermenter while 20.1 g kg(-1) in shake flask after 4 days of fungal treatment. The effective biodegradation of STP sludge was recorded in both fermenter and shake flask experiment compared to control (uninnoculated sample). The results presented in this study revealed that the overall performance of fermenter in terms of sludge cake (biosolids) accumulation and biodegradation of STP sludge was higher than the shake flask.

  2. Genotoxic and mutagenic effects of sewage sludge on higher plants.

    Science.gov (United States)

    Corrêa Martins, Maria Nilza; de Souza, Victor Ventura; Souza, Tatiana da Silva

    2016-02-01

    Sewage treatment yields sludge, which is often used as a soil amendment in agriculture and crop production. Although the sludge contains elevated concentrations of macro and micronutrients, high levels of inorganic and organic compounds with genotoxic and mutagenic properties are present in sludge. Application of sludge in agriculture is a pathway for direct contact of crops to toxic chemicals. The objective of this study was to compile information related to the genotoxic and mutagenic effects of sewage sludge in different plant species. In addition, data are presented on toxicological effects in animals fed with plants grown in soils supplemented with sewage sludge. Despite the benefits of using sewage sludge as organic fertilizer, the data showcased in this review suggest that this residue can induce genetic damage in plants. This review alerts potential risks to health outcomes after the intake of food cultivated in sewage sludge-amended soils. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Energy efficiency improvements in sewage sludge processing plants; Energetische Optimierung der Klaerschlammaufbereitung

    Energy Technology Data Exchange (ETDEWEB)

    Vetter, H.; Burger, S.

    2006-07-01

    From October 1st, 2006, sewage sludge may no longer be used as a fertilizer by farmers in Switzerland. Mechanical dewatering and drying of the sludge are the pre-stages of incineration. Based on a monitoring campaign and the results thereof, recommendations aiming at improving the energy efficiency have been worked out for use by waste water treatment plant operators and engineers for the design of drying plants. From the energetic point of view, solar drying of sludge is the best process. However, due to the large area required and the limited drying capacity, solar drying cannot be implemented everywhere. Therefore, three further drying processes have been monitored for eleven months: the fluidized bed drying process at the waste water treatment plant (WWTP) of the Region Berne, the low temperature/air recirculation dryer at WWTP Schwyz and the middle-temperature belt dryer at WWTP Wohlen. The electric energy consumption of the three investigated sludge drying processes was between 22 and 94 kWh per ton of evaporated water. The low temperature dryer showed the lowest energy consumption. The thermal energy consumption (expressed in useful energy) was between 648 and 1'033 kWh per ton of evaporated water, with the middle temperature dryer having the lowest consumption. On the other hand, the most advantageous process is the low temperature dryer if the comparison is based on the final energy consumption. This process has the advantage of making possible the integration of low-temperature waste heat. For whole Switzerland, the energy savings potential is estimated to be 133 GWh/year for fuel and 32 GWh/year for electricity, provided the drying process with the lowest energy consumption is implemented. It is recommended to conduct another measuring campaign at the first just commissioned sludge drying plant comprising a heat pump using waste water as a heat source, to check the effective energy savings. (author)

  5. Phage-host associations in a full-scale activated sludge plant during sludge bulking.

    Science.gov (United States)

    Liu, Ruyin; Qi, Rong; Wang, Juan; Zhang, Yu; Liu, Xinchun; Rossetti, Simona; Tandoi, Valter; Yang, Min

    2017-08-01

    Sludge bulking, a notorious microbial issue in activated sludge plants, is always accompanied by dramatic changes in the bacterial community. Despite large numbers of phages in sludge systems, their responses to sludge bulking and phage-host associations during bulking are unknown. In this study, high-throughput sequencing of viral metagenomes and bacterial 16S rRNA genes were employed to characterize viral and bacterial communities in a sludge plant under different sludge conditions (sludge volume index (SVI) of 180, 132, and 73 ml/g). Bulking sludges (SVI > 125 ml/g) taken about 10 months apart exhibited similar bacterial and viral composition. This reflects ecological resilience of the sludge microbial community and indicates that changes in viral and bacterial populations correlate closely with each other. Overgrowth of "Candidatus Microthrix parvicella" led to filamentous bulking, but few corresponding viral genotypes were identified. In contrast, sludge viromes were characterized by numerous contigs associated with "Candidatus Accumulibacter phosphatis," suggesting an abundance of corresponding phages in the sludge viral community. Notably, while nitrifiers (mainly Nitrosomonadaceae and Nitrospiraceae) declined significantly along with sludge bulking, their corresponding viral contigs were identified more frequently and with greater abundance in the bulking viromes, implying that phage-mediated lysis might contribute to the loss of autotrophic nitrifiers under bulking conditions.

  6. Sludge quantification at water treatment plant and its management scenario.

    Science.gov (United States)

    Ahmad, Tarique; Ahmad, Kafeel; Alam, Mehtab

    2017-08-15

    Large volume of sludge is generated at the water treatment plants during the purification of surface water for potable supplies. Handling and disposal of sludge require careful attention from civic bodies, plant operators, and environmentalists. Quantification of the sludge produced at the treatment plants is important to develop suitable management strategies for its economical and environment friendly disposal. Present study deals with the quantification of sludge using empirical relation between turbidity, suspended solids, and coagulant dosing. Seasonal variation has significant effect on the raw water quality received at the water treatment plants so forth sludge generation also varies. Yearly production of the sludge in a water treatment plant at Ghaziabad, India, is estimated to be 29,700 ton. Sustainable disposal of such a quantity of sludge is a challenging task under stringent environmental legislation. Several beneficial reuses of sludge in civil engineering and constructional work have been identified globally such as raw material in manufacturing cement, bricks, and artificial aggregates, as cementitious material, and sand substitute in preparing concrete and mortar. About 54 to 60% sand, 24 to 28% silt, and 16% clay constitute the sludge generated at the water treatment plant under investigation. Characteristics of the sludge are found suitable for its potential utilization as locally available construction material for safe disposal. An overview of the sustainable management scenario involving beneficial reuses of the sludge has also been presented.

  7. Leaching of heavy metals and alkylphenolic compounds from fresh and dried sewage sludge.

    Science.gov (United States)

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

    2014-02-01

    Reusing sewage sludge as a soil fertiliser has become a common alternative to disposal. Although this practice has a few benefits, it may contribute to the medium- and long-term contamination of the trophic chain because sewage sludge may contain heavy metals and organic contaminants. As the leaching of contaminants may depend on the sludge pre-treatment, the leaching of heavy metals (Cu, Ni, Pb, Zn and Cr) and alkylphenolic compounds (APCs) (octylphenol (OP), nonylphenol (NP), nonylphenol-mono-ethoxylate (NP1EO)) was investigated in five fresh and 40 °C dried sewage sludge samples from north-eastern Spain. FT-IR analyses and full-scan GC-MS chromatograms showed that sludge drying changed the nature of organic compounds leading to changes in their solubility. Moreover, sludge drying led to a higher relative contribution of dissolved organic carbon than the particulate organic carbon in the leachates. Leaching of Pb, Zn and Cr was below 5 % in both fresh and dried sludge samples, whereas Cu and Ni leached at rates up to 12 and 43 %, respectively, in some of the dried sludge samples. The leaching yields of OP, NP and NP1EO ranged from 1.3 to 35 % for fresh samples, but they decreased from 0.8 to 3.4 % in dried samples. The decrease in the leachability of APCs observed in dried sludge samples might be attributed to the fact that these compounds are associated with particulate organic matter, with significantly lower concentration or even absent in dried sludge than in fresh sludge samples. Therefore, it is recommended to dry the sludge before its disposal.

  8. Performance indicators and indices of sludge management in urban wastewater treatment plants.

    Science.gov (United States)

    Silva, C; Saldanha Matos, J; Rosa, M J

    2016-12-15

    Sludge (or biosolids) management is highly complex and has a significant cost associated with the biosolids disposal, as well as with the energy and flocculant consumption in the sludge processing units. The sludge management performance indicators (PIs) and indices (PXs) are thus core measures of the performance assessment system developed for urban wastewater treatment plants (WWTPs). The key PIs proposed cover the sludge unit production and dry solids concentration (DS), disposal/beneficial use, quality compliance for agricultural use and costs, whereas the complementary PIs assess the plant reliability and the chemical reagents' use. A key PI was also developed for assessing the phosphorus reclamation, namely through the beneficial use of the biosolids and the reclaimed water in agriculture. The results of a field study with 17 Portuguese urban WWTPs in a 5-year period were used to derive the PI reference values which are neither inherent to the PI formulation nor literature-based. Clusters by sludge type (primary, activated, trickling filter and mixed sludge) and by digestion and dewatering processes were analysed and the reference values for sludge production and dry solids were proposed for two clusters: activated sludge or biofilter WWTPs with primary sedimentation, sludge anaerobic digestion and centrifuge dewatering; activated sludge WWTPs without primary sedimentation and anaerobic digestion and with centrifuge dewatering. The key PXs are computed for the DS after each processing unit and the complementary PXs for the energy consumption and the operating conditions DS-determining. The PX reference values are treatment specific and literature based. The PI and PX system was applied to a WWTP and the results demonstrate that it diagnosis the situation and indicates opportunities and measures for improving the WWTP performance in sludge management. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. SLUDGE TREATMENT PROJECT PHASE 1 SLUDGE STORAGE OPTIONS ASSESSMENT OF T PLANT VERSUS ALTERNATE STORAGE FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    RUTHERFORD WW; GEUTHER WJ; STRANKMAN MR; CONRAD EA; RHOADARMER DD; BLACK DM; POTTMEYER JA

    2009-04-29

    The CH2M HILL Plateau Remediation Company (CHPRC) has recommended to the U.S. Department of Energy (DOE) a two phase approach for removal and storage (Phase 1) and treatment and packaging for offsite shipment (Phase 2) of the sludge currently stored within the 105-K West Basin. This two phased strategy enables early removal of sludge from the 105-K West Basin by 2015, allowing remediation of historical unplanned releases of waste and closure of the 100-K Area. In Phase 1, the sludge currently stored in the Engineered Containers and Settler Tanks within the 105-K West Basin will be transferred into sludge transport and storage containers (STSCs). The STSCs will be transported to an interim storage facility. In Phase 2, sludge will be processed (treated) to meet shipping and disposal requirements and the sludge will be packaged for final disposal at a geologic repository. The purpose of this study is to evaluate two alternatives for interim Phase 1 storage of K Basin sludge. The cost, schedule, and risks for sludge storage at a newly-constructed Alternate Storage Facility (ASF) are compared to those at T Plant, which has been used previously for sludge storage. Based on the results of the assessment, T Plant is recommended for Phase 1 interim storage of sludge. Key elements that support this recommendation are the following: (1) T Plant has a proven process for storing sludge; (2) T Plant storage can be implemented at a lower incremental cost than the ASF; and (3) T Plant storage has a more favorable schedule profile, which provides more float, than the ASF. Underpinning the recommendation of T Plant for sludge storage is the assumption that T Plant has a durable, extended mission independent of the K Basin sludge interim storage mission. If this assumption cannot be validated and the operating costs of T Plant are borne by the Sludge Treatment Project, the conclusions and recommendations of this study would change. The following decision-making strategy, which is

  10. SLUDGE TREATMENT PROJECT PHASE 1 SLUDGE STORAGE OPTIONS. ASSESSMENT OF T PLANT VERSUS ALTERNATE STORAGE FACILITY

    International Nuclear Information System (INIS)

    Rutherford, W.W.; Geuther, W.J.; Strankman, M.R.; Conrad, E.A.; Rhoadarmer, D.D.; Black, D.M.; Pottmeyer, J.A.

    2009-01-01

    The CH2M HILL Plateau Remediation Company (CHPRC) has recommended to the U.S. Department of Energy (DOE) a two phase approach for removal and storage (Phase 1) and treatment and packaging for offsite shipment (Phase 2) of the sludge currently stored within the 105-K West Basin. This two phased strategy enables early removal of sludge from the 105-K West Basin by 2015, allowing remediation of historical unplanned releases of waste and closure of the 100-K Area. In Phase 1, the sludge currently stored in the Engineered Containers and Settler Tanks within the 105-K West Basin will be transferred into sludge transport and storage containers (STSCs). The STSCs will be transported to an interim storage facility. In Phase 2, sludge will be processed (treated) to meet shipping and disposal requirements and the sludge will be packaged for final disposal at a geologic repository. The purpose of this study is to evaluate two alternatives for interim Phase 1 storage of K Basin sludge. The cost, schedule, and risks for sludge storage at a newly-constructed Alternate Storage Facility (ASF) are compared to those at T Plant, which has been used previously for sludge storage. Based on the results of the assessment, T Plant is recommended for Phase 1 interim storage of sludge. Key elements that support this recommendation are the following: (1) T Plant has a proven process for storing sludge; (2) T Plant storage can be implemented at a lower incremental cost than the ASF; and (3) T Plant storage has a more favorable schedule profile, which provides more float, than the ASF. Underpinning the recommendation of T Plant for sludge storage is the assumption that T Plant has a durable, extended mission independent of the K Basin sludge interim storage mission. If this assumption cannot be validated and the operating costs of T Plant are borne by the Sludge Treatment Project, the conclusions and recommendations of this study would change. The following decision-making strategy, which is

  11. The use of secondary energy for the drying of forest industry sludges - instead of destroying sludges to produce net energy; Jaetelaempoejen kaeyttoe metsaeteollisuuslietteiden kuivauksessa - lietteiden haevittaemisestae nettoenergian tuottamiseen - KLY 01

    Energy Technology Data Exchange (ETDEWEB)

    Pirkonen, P. [VTT Energy, Jyvaeskylae (Finland)

    1998-12-31

    The amount of waste water sludges in chemical forest industry was in 1995/1996 about 400 000 t dry solid matter and 70 % of these substances were incinerated mainly in the bark boilers. The rest were landfilled. Bio-, primary- and DlP-sludges and concentrate from debarking plant were dried with two laboratory scale layer dryers and pilot scale drum dryer. Bark, saw dust and peat were used as reference materials. Saw dust dried fastest and primary sludge slowest but the differences in the drying time between the dried materials were not large. The final moisture content could be 50 % and for example flue gases could be used as drying medium. Typical surface area of layer dryer needed to dry 40 000 t sludge from the moisture of 75 % to the moisture of 50 % could be 150 m{sup 2} and the value of investment could be 3-4 million FIM. Next step could be drying of sludges in pilot scale using some factories as references to get an idea of the real drying costs. (orig.)

  12. Growth, yield, and fruit quality of pepper plants amended with two sanitized sewage sludges.

    Science.gov (United States)

    Pascual, Immaculada; Azcona, Iñaki; Aguirreolea, Jone; Morales, Fermín; Corpas, Francisco Javier; Palma, José Manuel; Rellán-Alvarez, Rubén; Sánchez-Díaz, Manuel

    2010-06-09

    Organic wastes such as sewage sludge have been successfully used to increase crop productivity of horticultural soils. Nevertheless, considerations of the impact of sludges on vegetable and fruit quality have received little attention. Therefore, the objective of the present work was to investigate the impact of two sanitized sewage sludges, autothermal thermophilic aerobic digestion (ATAD) and compost sludge, on the growth, yield, and fruit quality of pepper plants ( Capsicum annuum L. cv. Piquillo) grown in the greenhouse. Two doses of ATAD (15 and 30% v/v) and three of composted sludge (15, 30, and 45%) were applied to a peat-based potting mix. Unamended substrate was included as control. ATAD and composted sludge increased leaf, shoot, and root dry matter, as well as fruit yield, mainly due to a higher number of fruits per plant. There was no effect of sludge on fruit size (dry matter per fruit and diameter). The concentrations of Zn and Cu in fruit increased with the addition of sewage sludges. Nevertheless, the levels of these elements remained below toxic thresholds. Pepper fruits from sludge-amended plants maintained low concentrations of capsaicin and dihydrocapsaicin, thus indicating low pungency level, in accordance with the regulations prescribed by the Control Board of "Lodosa Piquillo peppers" Origin Denomination. The application of sludges did not modify the concentration of vitamin C (ASC) in fruit, whereas the highest doses of composted sludge tended to increase the content of reduced (GSH) and oxidized (GSSG) glutathione, without change in the GSH/GSSG ratio. There were no effects of sludge on the transcript levels of enzymes involved in the synthesis of vitamin C, l-galactono-1,4-lactone dehydrogenase (GLDH) or in the ascorbate-glutathione cycle, ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR), and glutathione reductase (GR). Results suggest that the synthesis and degradation of ASC and GSH were compensated for in most of the

  13. Use of ready-mixed concrete plant sludge water in concrete containing an additive or admixture.

    Science.gov (United States)

    Chatveera, B; Lertwattanaruk, P

    2009-04-01

    In this study, we investigated the feasibility of using sludge water from a ready-mixed concrete plant as mixing water in concrete containing either fly ash as an additive or a superplasticizer admixture based on sulfonated naphthalene-formaldehyde condensates (SNF). The chemical and physical properties of the sludge water and the dry sludge were investigated. Cement pastes were mixed using sludge water containing various levels of total solids content (0.5, 2.5, 5, 7.5, 10, 12.5, and 15%) in order to determine the optimum content in the sludge water. Increasing the total solids content beyond 5-6% tended to reduce the compressive strength and shorten the setting time. Concrete mixes were then prepared using sludge water containing 5-6% total solids content. The concrete samples were evaluated with regard to water required, setting time, slump, compressive strength, permeability, and resistance to acid attack. The use of sludge water in the concrete mix tended to reduce the effect of both fly ash and superplasticizer. Sludge water with a total solids content of less than 6% is suitable for use in the production of concrete with acceptable strength and durability.

  14. Fertilization value of municipal sewage sludge for Eucalyptus camaldulensis plants

    Directory of Open Access Journals (Sweden)

    Soudani Leila

    2017-03-01

    Full Text Available The wastewater treatment produces a large amount of sludge. The different uses of eliminations sludge such as landfills or incineration have consequences negative for the environment, the agricultural use has increased worldwide, especially in crops and few or no studies have been conducted with forest plantations in Algeria. The objective of this study is to assess fertilizing characteristics of the sludge from the wastewater treatment plant of Tiaret (Algeria. One-year-old saplings of Eucalyptus camaldulensis were transplanted into pots with sludge/soil mixtures where sludge content was 20%, 40% and 60%. Biometric measurements (height, base diameter, diameter at mid-height and the number of leaves were performed during six months after planting. Results demonstrated the positive effect of sludge application. A significant difference in height increment and number of leaves was found between the control and sludge-treated plants. Biometric values for all sludge mixtures were higher than those for control plants (100% soil. The mixture, which contained 60% sludge, gives the best result, except for a diameter of stem. Plants grown on sludge/soil mixture had average height 49.4 ± 24.1 cm and average number of leaves 68.8 ± 6.2 while average height for plants grown on soil was 34.3 ± 12.8 cm and average number of leaves was 40 ± 3.8. Sludge application provides soil amendment and additional nutrient supply for planted trees.

  15. Agriculture reuse feasibility studies of sludges for the sewage sludge irradiation plant in Argentina

    International Nuclear Information System (INIS)

    Magnavacca, C.; Graino, J.C.

    1998-01-01

    The Argentine Sewage Sludge Irradiation Project, conceived by CNEA in 1992, decided the construction of an industrial-scale irradiation plant for disinfection of liquid sludges coming from a sewerage treatment plant and their recycling as fertilizers. This plant is being constructed and installed in Tucuman City in an agricultural zone of North Western Argentina. It is based on a gamma radiation process by batches of six cubic metres and using Argentine made Cobalt-60 sources. The feasibility studies on the Tucuman's Sewage Treatment Plant sludges involves: Technical parameters and chemical characterization of the sludges; Microbiological test to verify disinfection by irradiation; Toxic elements evaluation, both inorganic elements (heavy metals) and organic compounds (pesticide traces). These pollutant concentrations should meet the criteria set by the environmental regulations. Many of these experiments have been conducted within two Research Coordinated Programmes organized by the IAEA and the Joint FAO/IAEA Division. Another important aspect is the bioavailability of soil nutrients (N and P) from the sludges: it will determine the real economic value of sludges as fertilizers. Further studies on the behaviour of toxic elements accumulation on soil and plants, and also the capability of sludges to improve soil properties, will lead to the environment impact assessment of the application on land

  16. Sludge bio-drying: Effective to reduce both antibiotic resistance genes and mobile genetic elements.

    Science.gov (United States)

    Zhang, Junya; Sui, Qianwen; Tong, Juan; Buhe, Chulu; Wang, Rui; Chen, Meixue; Wei, Yuansong

    2016-12-01

    Sewage sludge is considered as one of major contributors to the increased environmental burden of ARGs. Sludge bio-drying was increasingly adopted due to its faster sludge reduction compared with composting. The fate of ARGs during full-scale sludge bio-drying was investigated to determine whether it could effectively reduce ARGs, and the contributions of bacterial community, horizontal gene transfer (HGT) through mobile genetic elements (MGEs) and co-selection from heavy metals to ARGs profiles were discussed in detail. Two piles with different aeration strategies (Pile I, the improved and Pile II, the control) were operated to elucidate effects of aeration strategy on ARGs profiles. Results showed that sludge bio-drying could effectively reduce both most of targeted ARGs (0.4-3.1 logs) and MGEs (0.8-3.3 logs) by the improved aeration strategy, which also enhanced both the sludge bio-drying performance and ARGs reduction. The enrichment of ARGs including ermF, tetX and sulII could be well explained by the evolution of bioavailable heavy metals, not HGT through MGEs, and their potential host bacteria mainly existed in Bacteroidetes. Although changes of bacterial community contributed the most to ARGs profiles, HGT through MGEs should be paid more attention especially in the thermophilic stage of sludge bio-drying. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Drying of sewage sludge; Le sechage des boues de stations d'epuration d'eaux urbaines

    Energy Technology Data Exchange (ETDEWEB)

    Pollet, O. [Seghers better technology (Belgium)

    2000-12-01

    Drying facilitates the valorization of sludge through different treatment routes. During drying, the sludge undergoes structural stages: plastic, granular and hardening stages. Sludge drying processes must be safe (explosion risks), respectful of environment (odor, dust), abrasion and corrosion resistant, flexible (varying sludge characteristics). A classification of these systems is proposed in the communication according to the following criteria: transition through the transit phase, heat transfer, drying/granulation in one step or post granulation, partial drying or complete drying. Various systems are described: rotary drum dryer, fluidized bed dryer, thin film dryer, disc dryer, paddle dryer, pipe bundle drum dryer, multi-tray dryer. (authors)

  18. Sewage sludge drying by energy recovery from OFMSW composting: preliminary feasibility evaluation.

    Science.gov (United States)

    Rada, Elena Cristina; Ragazzi, Marco; Villotti, Stefano; Torretta, Vincenzo

    2014-05-01

    In this paper an original energy recovery method from composting is analyzed. The integrated system exploits the heat available from the aerobic biochemical process in order to support the drying of sewage sludge, using a specific solar greenhouse. The aim is to tackle the problem of organic waste treatment, with specific regard to food waste. This is done by optimizing the energy consumption of the aerobic process of composting, using the heat produced to solve a second important waste management problem such as the sewage waste treatment. Energy and mass balances are presented in a preliminary feasibility study. Referring to a composting plant with a capacity of 15,000 t/y of food waste, the estimation of the power from recovered heat for the entire plant resulted about 42 kW. The results demonstrated that the energy recoverable can cover part of the heat necessary for the treatment of sludge generated by the population served by the composting plant (in terms of food waste and green waste collection). The addition of a renewable source such as solar energy could cover the residual energy demand. The approach is presented in detail in order for it to be replicated in other case studies or at full scale applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Disposal of sewage sludge. Rotary kiln plants and energetic utilization of sewage sludge; Klaerschlammentsorgung. Drehrohranlagen in der Trocknung und energetischen Nutzung von Klaerschlamm

    Energy Technology Data Exchange (ETDEWEB)

    Hormes, Franz [Visser und Smit Hanab GmbH, Kaarst (Germany). Rotary Kilns

    2013-03-01

    The author of the contribution under consideration reports on rotary kiln plants in the disposal of sewage sludge. The examples give an insight into the systems engineering for the thermal treatment of sewage sludge, for the minimization or full thermal utilization. The examples show that there exists any specific solution. The process selection depends on the legal requirements and the framework conditions in dependence from the site and infrastructure. Generally, the following statements are valid: (a) The co-combustion is cheaper than every mono-combustion; (b) The costs for the transport of wet sludge often are more favourable than the costs of drying; (c) Plants for low capacities are specifically expensive. The following criteria become more important: (a) energy costs, recycling of energy; (b) recycling of phosphorus from sewage sludge; (c) Reduction of the input of heavy metals in order to comply with the fertilizer ordinance.

  20. Sludge Reduction by Lumbriculus Variegatus in Ahvaz Wastewater Treatment Plant

    Directory of Open Access Journals (Sweden)

    Tim Hendrickx

    2012-08-01

    Full Text Available Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensivehealth hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm.The effects of changes in dissolved oxygen (DO concentration up to 3 mg/L (run 1 and up to 6 mg/L (run 2 were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. Theaverage sludge reductions were obtained as 33% (run 2 and 32% (run 1 in worm reactor,and 16% (run 1 and 12% (run 2 in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blankconditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing.

  1. Long term effects on petrochemical activated sludge on plants and soil. Plant growth and metal absorption

    Energy Technology Data Exchange (ETDEWEB)

    Tedesco, M.J.; Gianello, C. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Solos; Ribas, P.I.F.; Carvalho, E.B. [CORSAN-SITEL, Triunfo, RS (Brazil). Polo Petroquimico do Sul. Dept. de Operacao e Manutencao

    1993-12-31

    An experiment to study the effects of several application rates of excess activated sludge on plants, soil and leached water was started in 1985. Sludge was applied for six years and increased plant growth due to its nitrogen and phosphorous contribution, even though the decomposition rate in soil is low. Plant zinc, cadmium and nickel content increased with sludge application, while liming decreased the amounts of these metals taken up by plants. 9 refs., 8 tabs.

  2. MOBIL CONTAINER UNIT FOR SEWAGE SLUDGE UTILIZATION FROM SMALL AND MEDIUM WASTWATER TREATMENT PLANTS

    Directory of Open Access Journals (Sweden)

    Stanisław Ledakowicz

    2016-06-01

    Full Text Available The most wastewater treatment plants in Poland are small and medium plants of flow capacity below 1000 m3/d. These plants are not able to build sludge incineration plants and the transportation costs to the nearest plants increase the total costs of wastewater treatment. Polish company Metal Expert together with the French company ETIA and Lodz University of Technology proposed mobile unit for integrated drying and pyrolysis of sewage sludge in a pilot bench scale with capacity of 100 kg/h of dewatered sludge. The pilot plant was mounted in a typical mobile container which could provide service to small and medium wastewater treatment plants offering thermal processing of sewage sludge. This unit consists of KENKI contact dryer and „Spirajoule”® pyrolyser supplied with electricity utilizing the Joule effect, and a boiler, wherein the pyrolysis gases and volatile products are burned producing steam sent to the contact dryer. The bio-char produced during sludge pyrolysis could be utilized for agriculture purposes. During preliminary experiments and short-term exploitation of the unit at Elbląg Wastewater Treatment Plant the obtained results allowed us to make a mass and energy balance depended on the process conditions in the pyrolysis temperature range of 400÷800 °C. Based on the obtained results a calculator was created in the Excel , which enables assessment of pyrolysis products content and making mass and energy balances depended on process parameters such as initial moisture of sludge, pyrolysis temperature and installation output.

  3. Influence of forced air volume on water evaporation during sewage sludge bio-drying.

    Science.gov (United States)

    Cai, Lu; Chen, Tong-Bin; Gao, Ding; Zheng, Guo-Di; Liu, Hong-Tao; Pan, Tian-Hao

    2013-09-01

    Mechanical aeration is critical to sewage sludge bio-drying, and the actual water loss caused by aeration can be better understood from investigations of the relationship between aeration and water evaporation from the sewage sludge bio-drying pile based on in situ measurements. This study was conducted to investigate the effects of forced air volume on the evaporation of water from a sewage sludge bio-drying pile. Dewatered sewage sludge was bio-dried using control technology for bio-drying, during which time the temperature, superficial air velocity and water evaporation were measured and calculated. The results indicated that the peak air velocity and water evaporation occurred in the thermophilic phase and second temperature-increasing phase, with the highest values of 0.063 ± 0.027 m s(-1) and 28.9 kg ton(-1) matrix d(-1), respectively, being observed on day 4. Air velocity above the pile during aeration was 43-100% higher than when there was no aeration, and there was a significantly positive correlation between air volume and water evaporation from day 1 to 15. The order of daily means of water evaporation was thermophilic phase > second temperature-increasing phase > temperature-increasing phase > cooling phase. Forced aeration controlled the pile temperature and improved evaporation, making it the key factor influencing water loss during the process of sewage sludge bio-drying. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Effects of gamma radiation at pilot plant level compared with the effects of pasteurization on the dewatering of sewage sludges

    International Nuclear Information System (INIS)

    Groneman, A.F.

    1975-01-01

    Dewatering and disposal of sludge are costly and time consuming processes. At a pilot plant near Munich efforts were made to estimate the effects of ionizing radiation on dewatering characteristics of different sludges, used for recycling in agriculture. The ease with which sludge drains on drying beds and in mechanical devices is reflected in the value of the specific resistance to filtration. A dose of 300 krad, delivered at an average dose rate of 62 krad per hour in the irradiation plant, was effective for disinfection and reduced the specific resistance to filtration in sludges from the waste-water works at Geiselbullach and Starnberg from 24.2 x 10 9 s 2 /g and 18.0 x 10 9 s 2 /g to 9.7 x 10 9 s 2 /g and 5.6 x 10 9 s 2 /g respectively. These improved dewatering properties were associated with a clear increase in the compressibility of the anaerobically digested sludges. Pasteurization at 70degC during 30 minutes drastically reduced the dewatering properties, raising the specific resistance to values approximately four times as high as the specific resistance in irradiated sludges. Information obtained from filterability tests was confirmed by plant operators who noticed that irradiated sludges dewatered much better than untreated sludges in drying beds. Experimental evidence indicated that the conditioning effect of gamma irradiation persisted for more than 20 days suggesting that permanent changes were induced in the physical-chemical properties of the domestic, anaerobically digested sludges. Measurements of electrophoretic mobilities showed that the negative electrostatic charges of colloidal particles in sludges were reduced by gamma irradiation whereas pasteurization increased this negative electrostatic charge. Evidence indicated that the specific resistance was considerably increased by effects of the recirculating pumping. This pumping is done to obtain a homogeneous irradiation dose for disinfection. Alternative designs for irradiation plants are

  5. Dry co-digestion of sewage sludge and rice straw under mesophilic and thermophilic anaerobic conditions.

    Science.gov (United States)

    Chu, Xiangqian; Wu, Guangxue; Wang, Jiaquan; Hu, Zhen-Hu

    2015-12-01

    Dry anaerobic digestion of sewage sludge can recover biogas as energy; however, its low C/N ratio limits it as a single substrate in the anaerobic digestion. Rice straw is an abundant agricultural residue in China, which is rich in carbon and can be used as carbon source. In the present study, the performance of dry co-digestion of sewage sludge and rice straw was investigated under mesophilic (35 °C) and thermophilic (55 °C) conditions. The operational factors impacting dry co-digestion of sewage sludge and rice straw such as C/N ratio, moisture content, and initial pH were explored under mesophilic conditions. The results show that low C/N ratios resulted in a higher biogas production rate, but a lower specific biogas yield; low moisture content of 65 % resulted in the instability of the digestion system and a low specific biogas yield. Initial pH ranging 7.0-9.0 did not affect the performance of the anaerobic digestion. The C/N ratio of 26-29:1, moisture content of 70-80 %, and pH 7.0-9.0 resulted in good performance in the dry mesophilic co-digestion of sewage sludge and rice straw. As compared with mesophilic digestion, thermophilic co-digestion of sewage sludge and rice straw significantly enhanced the degradation efficiency of the substrates and the specific biogas yield (p sewage sludge under mesophilic and thermophilic conditions.

  6. Solidification of low-volume power plant sludges. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bell, N.E.; Halverson, M.A.; Mercer, B.M.

    1981-12-01

    A literature review was conducted to obtain information on the status of hazardous waste solidification technology and application of this technology to low-volume power plant waste sludges. Because of scarcity of sludge composition data, anticipated major components were identified primarily by chemical reactions that are known to occur during treatment of specific wastewaters. Chemical and physical properties of these sludges were critically analyzed for compatibility with several types of commercially available solidification processes. The study pointed out the need for additional information on the nature of these sludges, especially leaching characteristics and the presence of substances that will interfere with solidification processes. Laboratory studies were recommended for evaluation of solidification process which have the greatest potential for converting hazardous low-volume sludges to non-hazardous waste forms.

  7. PBDEs versus NBFR in wastewater treatment plants: occurrence and partitioning in water and sludge

    Directory of Open Access Journals (Sweden)

    Joyce Cristale

    2015-06-01

    Full Text Available This study evaluates the occurrence of flame retardants (FR in five wastewater treatment plants (WWTPs located close to Barcelona (NE Spain, an area with high urban and industrial pressures. Compounds studied include eight polybromodiphenyl ethers (PBDEs and eight New Brominated Flame Retardants (NBFRs, for which little information regarding their presence, partitioning and fate within the WWTPs is available. In unfiltered influent samples, PBDEs were not detected and bis(2-ethyl-1-hexyltetrabromophthalate was the only NBFR detected, and all WWTPs were efficient in eliminating this compound as no residues were found in the effluents. However, primary sludge contained from 279 to 2299 ng/g dry weight of ΣFR and the concentration increased in secondary (biological sludge. NBFRs accounted for the main FR detected in sludge, representing a 63-97% of the total load, and among PBDEs, BDE-209 was the most ubiquitous congener. Considering the amount of sludge generated in each WWTP, it was estimated that 0.34-17.2 kg of FR are released annually through the sludge, which can have negative environmental and health implications if sludge is used as biosolid in agriculture. Overall, this study provides a sampling design and analytical protocol to be used to determine the evolution of FR in WWTPs and compares the levels detected, considering that PBDEs are being phased out to be substituted by other compounds which also have high accumulative and recalcitrant properties.

  8. ENERGY SLUDGE PROCESSING IN A SEPARATE WASTEWATER TREATMENT PLANT DIGESTER POMORZANY IN SZCZECIN

    Directory of Open Access Journals (Sweden)

    Anna Iżewska

    2016-06-01

    Full Text Available Pomorzany Sewage Treatment Plant in Szczecin ensures the required parameters of treated sewage. However, due to higher efficiency of sewage treatment, more sludge is produced after the treatment process. In the examined sludge treatment plant, primary sludge is gravitationally thickened to the content of about 5% of dry matter, and the excessive is thickened in mechanical compactors up to 6% of dry matter. Settlements preliminary and excessive after compaction is discharged to the sludge tank where a pump is forced into two closed digesters. Each digester has the capacity of 5069 m3. At a temperature of about 37 °C a mesophilic digestion is performed. Biogas, that is produced in the chamber, is stored in two-coat tanks with the capacity of 1500 m3 each and after desulphurization with the biosulfex method (which results with obtaining elemental sulphur it is used as fuel in cogeneration units. The aim of this study was to determine amount of energy given by sewage sludge in the form of heat during the process of methane digestion (primary and excessive. These amounts were determined on the basis of chemical energy balance of sewage carried into and out of Separate Sludge Digesters and produced biogas within 24h. The study determined that the percentage value of average chemical energy amount turned into heat and discharged with produced methane in relation to chemical energy of sewage carried into the first digester in Pomorzany Treatment Plant in Szczecin was in the range of 47.86 ± 9.73% for a confidence level of 0.95. On average 80.86 ± 33.65% was emitted with methane and 19.14 ± 33.65% of energy was changed into heat.

  9. Drying of residue and separation of nitrate salts in the sludge waste for the lagoon sludge treatment

    International Nuclear Information System (INIS)

    Hwang, D. S.; Lee, K. I.; Choi, Y. D.; Hwang, S. T.; Park, J. H.

    2003-01-01

    This study investigated the dissolution property of nitrate salts in the dissolution process by water and the drying property of residue after separating nitrates in a series of the processes for the sludge treatment. Desalination was carried out with the adding ratio of water and drying property was analyzed by TG/DTA, FTIR, and XRD. Nitrate salts involved in the sludge were separated over 97% at the water adding ratio of 2.5. But a small quantity of calcium and sodium nitrate remained in the residue These were decomposed over 600 .deg. C and calcium carbonate, which was consisted mainly of residue, was decomposed into calcium oxide over 750 .deg. C. The residue have to be decomposed over 800 .deg. C to converse uranyl nitrate of six value into the stable U 3 O 8 of four value. As a result of removing the nitrates at the water adding ratio of 2.5 and drying the residue over 900 .deg. C, volume of the sludge waste decreased over 80%

  10. New biological deodrization device using dried activated sludge. Kanso odei wo mochiita shinki seibutsu dasshu sochi no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, S.; Nagayasu, K.; Suwa, T.; Hayashitani, M.; Ito, H.; Habata, K.; Kitakaze, T. (Kawasaki Heavy Industries, Ltd., Tokyo (Japan))

    1993-10-20

    The new biological deodorization device was developed using dried activated sludge as deodorant. Activated sludge obtained from a waste water treatment plant was dried at room temperature to protect from extinction of microorganisms in it before its charge into the device, and washed by water only as required. Offensive odor substances were oxidation-decomposed by microorganism after their adsorption into sludge surfaces, while microorganisms survived for a long time while getting such substances as nutritive sources. As basic deodorization characteristics were studied with the experimental device and artificial odor gases, more than 99% of 200 and 2,000 ppm H2S were removed at space velocities of 400/h and 33/h, respectively, together with nine typical offensive odor substances. As the result of demonstration tests with the small test device installed in a public waste water treatment plant, a high deodorizing efficiency was retained for 10 months or more, and its running cost was as low as 75% of that of current systems because of only one necessary washing every month. 3 refs., 14 figs., 12 tabs.

  11. The effect of lime-dried sewage sludge on the heat-resistance of eco-cement.

    Science.gov (United States)

    Li, Wen-Quan; Liu, Wei; Cao, Hai-Hua; Xu, Jing-Cheng; Liu, Jia; Li, Guang-Ming; Huang, Juwen

    2016-01-01

    The treatment and disposal of sewage sludge is a growing problem for sewage treatment plants. One method of disposal is to use sewage sludge as partial replacement for raw material in cement manufacture. Although this process has been well researched, little attention has been given to the thermal properties of cement that has had sewage sludge incorporated in the manufacturing process. This study investigated the fire endurance of eco-cement to which lime-dried sludge (LDS) had been added. LDS was added in proportions of 0%, 3%, 6%, 9%, and 12% (by weight) to the raw material. The eco-cement was exposed to 200, 400, or 600 °C for 3 h. The residual strength and the microstructural properties of eco-cement were then studied. Results showed that the eco-cement samples suffered less damage than conventional cement at 600 °C. The microstructural studies showed that LDS incorporation could reduce Ca(OH)(2) content. It was concluded that LDS has the potential to improve the heat resistance of eco-cement products.

  12. Dehydrating sewage plant sludge using a mobile centrifuge; Deshidratacion de fangos en las depuradoras mediante una centrifuga movil

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Palou, P.; Arnau Planas de Farnes, A.; Arnau Figuerola, J.

    1997-09-01

    This study set out to examine various mechanical sludge dehydration systems as alternatives to the drying beds currently in existence in the sewage plants managed by the Costa Brava Consortium at Portbou, Colera, El Port de la Selva and Cadaques by determining their technical and economic feasibility. (Author) 11 refs.

  13. The Assessment of Water Treatment Plant Sludge Properties and the Feasibility of Its Re-use according to Environmental Standards: Shahid Beheshti Water Treatment Plant Case Study, Hamadan

    Directory of Open Access Journals (Sweden)

    H. Pourmand

    2016-04-01

    Full Text Available Introduction & Objectives: Water treatment leads to produce large volumes of sludges in water treatment plants which are considered as solid waste, and should be managed appropriately and logically to avoid bioenvironmental effects. Materials & Methods: In this cross-sectional study, the required samples were taken from the sludge of Shahid Beheshti water treatment plant to assay physical and chemical characteristics during one year from summer, autumn and winter 93 until spring 94. Sampling and testing procedures were full fit according to standard methods. Results: The average concentration of total solids parameters (TSS, total suspended solids (TSS, and total dissolved solids (TDS were 22346, 21350 and 1005 mg/L, respectively. Among the heavy metals, aluminum, iron, manganese and zinc have the highest concentrations with the values of 1400, 956, 588 and 100 mg per kg of dry solids, respectively. The measured concentrations for cadmium were also higher than the permissible limits for agricultural purposes and discharges into the environment. The average concentrations of nickel were more than the recommended standard for industrial, agricultural and parkland application purposes. The concentrations were also slurry higher than the dry sludge. Conclusion: According to the past studies and results of this study, it could be concluded that contamination of heavy metals in sludge and slurry samples are more than dried sludge, .Therefore, if they are discharged into the environment, it is better to be disposed as dry sludges. Furthermore, because these types of waste sludges are routinely disposed in the environment, it is recommended to take the routine samples in order to measure the heavy metals and other relevant parameters contents of sludge before discharging it. (Sci J Hamadan Univ Med Sci 2016; 23 (1:57-64

  14. Physical and Chemical Properties of Sewage Sludge and the Final Disposal of Sewage Sludge from the Central Wastewater Treatment Plant Kranj

    OpenAIRE

    Dolenec, Matjaž

    2016-01-01

    The aim of the presented study was to examine physical and chemical characteristics of sewage sludge from the central wastewater treatment plant (CWWTP) in Kranj and examine the final sewage sludge disposal. Heavy metals are one of the main pollutantsthat are present in the sewage sludge. Their concentration is very important for the final sewage sludge disposal. In the first part,the study presents the Slovenian legislation of sewage sludge.It outlines the possibilities of the final sludg...

  15. Social and environmental aspects of a sewage sludge irradiation plant

    International Nuclear Information System (INIS)

    Mangussi, J.

    2000-01-01

    The critical environmental parameters involved in an environmental impact study for a 700,000 Ci of 60 Co sewage sludge irradiation plant are described and analyzed. The plant is the first that will operate in Argentina and it is located in a town of 500,000 inhabitants, in an agricultural region with no nuclear tradition. The position of the environmental authorities and of the public opinion is analyzed. Possible information alternatives are proposed. (author)

  16. Transfer of Cobalt-60 to plants from soils treated with sewage sludge

    International Nuclear Information System (INIS)

    Grummitt, W.E.

    1976-01-01

    The uptake of 60 Co from soils fertilized with contaminated sewage sludge has been investigated under a variety of experimental conditions. A number of garden plots were prepared by thoroughly mixing sludge containing 60 Co with farm soils from the Ottawa Valley. Edible plants were grown in the open on these plots under conditions approximating those in market gardens. The crops were harvested at maturity and were prepared for measurement of 60 Co by drying portions of the roots, leaves, stems and fruit. The samples were counted on a large germanium detector which was capable of resolving 60 Co from other gamma-emitting nuclides. Cobalt was readily taken up from contaminated sludge but was nonuniformly distributed in various parts of the plant. In general, the roots showed the highest levels while edible portions such as seeds and tubers had much lower concentrations. The uptake ratio, expressed as radioactivity in the sample to radioactivity in the soil, varied from 0.003 to 8 on a dry-weight basis. (author)

  17. Transfer of 60Co to plants from soils treated with sewage sludge

    International Nuclear Information System (INIS)

    Grummitt, W.E.

    1976-01-01

    The uptake of 60 Co from soils fertilized with contaminated sewage sludge has been investigated under a variety of experimental conditions. A number of garden plots were prepared by thoroughly mixing sludge containing 60 Co with farm soils from the Ottawa Valley. Edible plants were grown in the open on these plots under conditions approximating those in market gardens. The crops were harvested at maturity and were prepared for measurement of 60 Co by drying portions of the roots, leaves, stems and fruit. The samples were counted on a large germanium detector which was capable of resolving 60 Co from other gamma-emitting nuclides. Cobalt was readily taken up from contaminated sludge but was nonuniformly distributed in various parts of the plant. In general, the roots showed the highest levels while edible portions such as seeds and tubers had much lower concentrations. The uptake ratio, expressed as radioactivity in the sample to radioactivity in the soil, varied from 0.003 to 8 on a dry-weight basis

  18. Increased biogas production at wastewater treatment plants through co-digestion of sewage sludge with grease trap sludge from a meat processing plant.

    Science.gov (United States)

    Luostarinen, S; Luste, S; Sillanpää, M

    2009-01-01

    The feasibility of co-digesting grease trap sludge from a meat-processing plant and sewage sludge was studied in batch and reactor experiments at 35 degrees C. Grease trap sludge had high methane production potential (918 m(3)/tVS(added)), but methane production started slowly. When mixed with sewage sludge, methane production started immediately and the potential increased with increasing grease trap sludge content. Semi-continuous co-digestion of the two materials was found feasible up to grease trap sludge addition of 46% of feed volatile solids (hydraulic retention time 16d; maximum organic loading rate 3.46 kgVS/m(3)d). Methane production was significantly higher and no effect on the characteristics of the digested material was noticed as compared to digesting sewage sludge alone. At higher grease trap sludge additions (55% and 71% of feed volatile solids), degradation was not complete and methane production either remained the same or decreased.

  19. Hydrothermal Liquefaction and Upgrading of Municipal Wastewater Treatment Plant Sludge: A Preliminary Techno-Economic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Snowden-Swan, Lesley J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhu, Yunhua [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Susanne B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elliott, Douglas C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schmidt, Andrew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hallen, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billing, Justin M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Todd R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fox, Samuel P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Maupin, Gary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-06-08

    A preliminary process model and techno-economic analysis (TEA) was completed for fuel produced from hydrothermal liquefaction (HTL) of sludge waste from a municipal wastewater treatment plant (WWTP) and subsequent biocrude upgrading. The model is adapted from previous work by Jones et al. (2014) for algae HTL, using experimental data generated in fiscal year 2015 (FY15) bench-scale HTL testing of sludge waste streams. Testing was performed on sludge samples received from MetroVancouver’s Annacis Island WWTP (Vancouver, B.C.) as part of a collaborative project with the Water Environment and Reuse Foundation (WERF). The full set of sludge HTL testing data from this effort will be documented in a separate report to be issued by WERF. This analysis is based on limited testing data and therefore should be considered preliminary. Future refinements are necessary to improve the robustness of the model, including a cross-check of modeled biocrude components with the experimental GCMS data and investigation of equipment costs most appropriate at the smaller scales used here. Environmental sustainability metrics analysis is also needed to understand the broader impact of this technology pathway. The base case scenario for the analysis consists of 10 HTL plants, each processing 100 dry U.S. ton/day (92.4 ton/day on a dry, ash-free basis) of sludge waste and producing 234 barrel per stream day (BPSD) biocrude, feeding into a centralized biocrude upgrading facility that produces 2,020 barrel per standard day of final fuel. This scale was chosen based upon initial wastewater treatment plant data collected by the resource assessment team from the EPA’s Clean Watersheds Needs Survey database (EPA 2015a) and a rough estimate of what the potential sludge availability might be within a 100-mile radius. In addition, we received valuable feedback from the wastewater treatment industry as part of the WERF collaboration that helped form the basis for the selected HTL and upgrading

  20. The content of chromium and copper in plants and soil fertilized with sewage sludge with addition of various amounts of CaO and lignite ash

    Directory of Open Access Journals (Sweden)

    Wysokiński Andrzej

    2016-09-01

    Full Text Available The influence of fertilization with fresh sewage sludge with the addition of calcium oxide and lignite ash in the proportions dry mass 6:1, 4:1, 3:1 and 2:1 on the content of chromium and copper in plants and soil and uptake of these elements was investigated in pot experiment. Sewage sludge were taken from Siedlce (sludge after methane fermentation and Łuków (sludge stabilized in oxygenic conditions, eastern Poland. The chromium content in the biomass of the test plants (maize, sunflower and oat was higher following the application of mixtures of sewage sludge with ash than of the mixtures with CaO. The copper content in plants most often did not significantly depend on the type of additives to the sludge. Various amounts of additives to the sewage sludge did not have a significant effect on the contents of either of the studied trace elements in plants. The contents of chromium and copper in soil after 3 years of cultivation of plants were higher than before the experiment, but these amounts were not significantly differentiated depending on the type and the amount of the used additive (i.e. CaO vs. ash to sewage sludge.

  1. Sewage sludge as a sensitive indicator for airborne radionuclides from nuclear power plants

    International Nuclear Information System (INIS)

    Ingemansson, T.

    1982-01-01

    Sewage sludge collected at waste water treatment plants located in the vicinity of nuclear power stations, has been shown to be a sensitive and convenient indicator for airborne locally released activation products, 60 Co, 65 Zn, 58 Co and 54 Mn. We have therefore been able to study the distribution and behaviour of these radionuclides in the terrestrial environment of three Swedish nuclear power stations. Comparative measurements on ground level air and on samples of lichen (Cladonia alpestris) and soil have also been performed. The variation by distance from the power station of 60 Co measured in sludge as well as on air-filters could be described by the same power function. The temporal variation of the activity concentration in sludge samples well reflects the variation of the reported release rate of airborne radionuclides from the power stations if the prevalent wind direction is taken into consideration. The relation between the activity ratio 60 Co/ 7 Be in air and in sludge was investigated and indicated that most of the detected 60 Co and part of 58 Co and 54 Mn activity is released from a local source and is dry deposited on the ground before it is washed off by rain. (Author)

  2. Combustion of Dried Sewage Sludge in a Fluidized-Bed Reactor

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Trnka, Otakar

    2005-01-01

    Roč. 44, č. 10 (2005), s. 3432-3441 ISSN 0888-5885 R&D Projects: GA AV ČR(CZ) IAA4072201 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidized-bed combustion * dried sewage sludge * CO, NOx, and N2O emissions Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.504, year: 2005

  3. Experimental plant for sludge composting. Plant experimental de compostaje de lodos

    Energy Technology Data Exchange (ETDEWEB)

    Cadenas, A.; Caellas, N.; Amengual, A.; Calafact, J.

    1993-01-01

    Results and expertise collected during the first year of exploitation of a compost experimental plant located in Mallorca (Spain): The plant is treating sludge from the biological treatment plant of water at the town of Felanitx and the compost produced is used in agriculture. (Author)

  4. Effects of gamma-radiation at pilot plant level as compared to effects of pasteurization on the dewatering of sewage sludges

    International Nuclear Information System (INIS)

    Groneman, A.F.

    1975-01-01

    Dewatering and disposal of sludge are costly and time consuming processes. At a pilot plant near Munich efforts were made to estimate the effects of ionizing radiation on dewatering characteristics of different sludges, used for recycling in agriculture. The ease with which sludge drains on drying beds and in mechanical devices is reflected in the value of the specific resistance to filtration. A dose of 300 krad, delivered at an average dose rate of 62 krad per hour in the irradiation plant, was effective for disinfection and reduced the specific resistance to filtration in sludges from the waste water works at Geiselbullach and Starnberg from 24.2 x 10 9 sec 2 /g and 18.0 x 10 9 sec 2 /g to 9.7 x 10 9 sec 2 /g and 5.6 x 10 9 sec 2 /g, respectively. These improved dewatering properties were associated with a clear increase of the compressibility of the anaerobically digested sludges. Pasteurization at 70 0 C during 30 minutes drastically deteriorated the dewatering properties, raising the specific resistance to values approximately 4 times as high as the specific resistance in irradiated sludges. Information obtained from filterability tests was confirmed by plant operators who noticed that irradiated sludges dewatered much better than untreated sludges in drying beds. Experimental evidence indicated that the conditioning effect of gamma irradiation persisted for more than 20 days suggesting that permanent changes were induced in the physical-chemical properties of the domestic, anaerobically digested sludges. Measurements of electrophoretic mobilities showed that the negative electrostatic charges of colloidal particles in sludges were reduced by gamma irradiation whereas pasteurization increased this negative electrostatic charge. Evidence indicated that the specific resistance was considerably increased by effects of the recirculating pumping. This pumping is done to obtain a homogeneous irradiation dose for disinfection. Alternative designs for irradiation

  5. Experience with a pilot plant for the irradiation of sewage sludge: Results on the effect of differently treated sewage sludge on plants and soil

    International Nuclear Information System (INIS)

    Suess, A.; Rosopulo, A.; Borchert, H.; Beck, Th.; Bauchhenss, J.; Schurmann, G.

    1975-01-01

    Since hygienization of sewage sludge will be important for an agricultural application it is necessary to study the effect of differently treated sewage sludge on plants and soil. In bean and maize experiments in 1973 and 1974 it was found that the treatment of sewage sludge is less important than soil properties and water capacity. Analysis on the efficiency of nutrients, minor elements and heavy metals from differently treated sewage sludge to plants were performed. Microbiological greenhouse studies indicated that there is a distinct tendency for different reactions, that irradiated sewage sludge gives a slightly better effect than untreated sludge, while the heat-treated sewage sludge indicates always a decrease, especially with the increase of applied amounts (respiration, protease and nitrification). In the field experiments there were almost no differences between untreated and irradiated sewage sludge, whereas there was always a smaller microbial activity after application of heat-treated sewage sludge. Studies on soil fauna (especially on Collemboles and Oribatidae) in the field trials indicate the influences of abiotic factors on the different locations. Besides these influences there was a decrease in the number of Collemboles and mites (in comparison with a normal fertilized plot) on the plots with 800 m 3 /ha treated sewage sludge. There was a remarkably large decrease in the plots with irradiated sewage sludge after an application of 800 m 3 /ha. Depending on the soil type, physical and chemical studies indicated an increase in the effective field capacity after the application of sewage sludge, and sometimes the best effects occurred with irradiated sewage sludge. Relative high aggregate values were observed (6-2, 6-5 mm diameter) in the plots with irradiated sewage sludge. (author)

  6. Self-heating of dried industrial wastewater sludge: lab-scale investigation of supporting conditions.

    Science.gov (United States)

    Della Zassa, M; Biasin, A; Zerlottin, M; Refosco, D; Canu, P

    2013-06-01

    We studied the reactivity of dried sludge produced by treatment of wastewater, mainly from tanneries. The solids transformations have been first characterized with thermal analysis (TGA and DSC) proving that exothermic transformation takes place at fairly low temperature, before the total organic combustion that occurs in air above 400°C. The onset of low temperature reactions depends on the heating rate and it can be below 100°C at very small heating rate. Then, we reproducibly determined the conditions to trigger dried sludge self-heating at the laboratory scale, on samples in the 0.2-0.3 kg size. Thermal insulation, some aeration and addition of water are key factors. Mastering the self-heating at this scale allows more detailed investigations as well as manipulation of conditions, to understand its nature, course and remediation. Here we report proves and discussions on the role of air, water, particle size, porosity and biological activity, as well as proving that also dried sludge from similar sources lead to self-heating. Tests demonstrate that air and water are simultaneously required for significant self-heating to occur. They act in diverging directions, both triggering the onset of the reactions and damping the temperature rise, by supporting heat loss. The higher the O2 concentration, the higher the solids heating rate. More added water prolongs the exothermic phase. Further additions of water can reactivate the material. Water emphasizes the exothermic processes, but it is not sufficient to start it in an air-free atmosphere. The initial solid moisture concentration (between 8% and 15%) affects the onset of self-heating as intuitive. The sludge particles size strongly determines the strength and extent of the heat release, indicating that surface reactions are taking place. In pelletized particles, limitations to water and air permeability mitigates the reaction course. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Organophosphate Triesters and Diester Degradation Products in Municipal Sludge from Wastewater Treatment Plants in China: Spatial Patterns and Ecological Implications.

    Science.gov (United States)

    Fu, Lingfang; Du, Bibai; Wang, Fei; Lam, James C W; Zeng, Lixi; Zeng, Eddy Y

    2017-12-05

    Little is known about the occurrences, distributions, sources, and potential risks of organophosphate (OP) triesters and diester degradation products in municipal sludge from wastewater treatment plants (WWTPs). In this study, we conducted the first nationwide survey to simultaneously determine a suite of 11 OP triesters and six diester degradation products in sludge from WWTPs across China. All OP triesters were detected and three diesters were identified for the first time in sludge samples. Total concentrations of OP triesters and diester degradation products were in the ranges of 43.9-2160 and 17.0-1300 ng (g of dry weight) -1 , respectively, indicating relatively low pollution levels in China compared with those of several developed countries. A distinct geographical variation of higher concentrations of OP triesters and diesters in East China than in Central and West China was observed, suggesting that regional levels of organophosphate esters are associated with the magnitudes of regional economic development. Source analysis revealed nonchlorinated OP diesters are mainly derived from degradation in WWTPs, while chlorinated OP diesters were largely sourced from outside WWTPs. The estimated total emission fluxes of OP triesters and diesters via land-application sludge in China were approximately 330 and 134 kg/year, respectively. Further risk assessment based on risk quotient values in sludge-applied soils indicated low to medium risks for most OP triesters and diesters except tris(methylphenyl) phosphate. The significant accumulation of OP triesters and widespread occurrence of diester degradation products in sludge raise environmental concerns about these contaminants.

  8. Temporal evolution of polycyclic aromatic hydrocarbons (PAHs) in sludge from wastewater treatment plants: comparison between PAHs and heavy metals.

    Science.gov (United States)

    Villar, P; Callejón, M; Alonso, E; Jiménez, J C; Guiraúm, A

    2006-07-01

    This paper presents results on the presence and temporal variability of the 16 PAHs recommended by the EPA in primary, secondary and digested sewage sludge over a year. The sewage sludges originated from the Guadalete wastewater treatment plant (WWTP) site in Jerez de la Frontera (Cádiz, Spain). These organic pollutants have been extracted from the sewage sludge by microwave energy. High performance liquid chromatography coupled with diode array (HPLC-DAD) or fluorescence (HPLC-FL) detectors have been used. The results showed that total PAHs concentration varied between 1,945 ng g(-1) dry matter (DM) for primary sludges collected in March and 10,100 ng g(-1) DM for primary sludge collected in June. Generally, concentrations of PAHs were higher in compost and digested sludge than in fresh one. On the other hand, the highest concentration of PAHs were found on summer. This thing is associated to the traffic increase from inland zones to the coast (Jerez de la Frontera is very near to beaches). Finally, this paper present a comparative study of the American an European legislation concluding that the limits of concentrations established are not exceeded. In addition heavy metals were analysed. The origin of PAHs and heavy metals seems to be different.

  9. Influence of wastewater treatment plants' operational conditions on activated sludge microbiological and morphological characteristics.

    Science.gov (United States)

    Amanatidou, Elisavet; Samiotis, Georgios; Trikoilidou, Eleni; Tzelios, Dimitrios; Michailidis, Avraam

    2016-01-01

    The effect of wastewater composition and operating conditions in activated sludge (AS) microbiological and morphological characteristics was studied in three AS wastewater treatment plants (WWTPs): (a) a high organic load slaughterhouse AS WWTP, operating at complete solids retention, monitored from its start-up and for 425 days; (b) a seasonally operational, low nitrogen load fruit canning industry AS WWTP, operating at complete solids retention, monitored from its start-up and until the end of the season (87 days); (c) a municipal AS WWTP, treating wastewater from a semi-combined sewer system, monitored during the transitions from dry to rainy and again to dry periods of operation. The sludge microbiological and morphological characteristics were correlated to nutrients' availability, solids retention time, hydraulic retention time, dissolved oxygen, mixed liquor suspended solids (MLVSS), organic load (F/M) and substrate utilization rate. The AS WWTPs' operation was distinguished in periods based on biomass growth phase, characterized by different biological and morphological characteristics and on operational conditions. An anoxic/aerobic selector minimizes the readily biodegradable compounds in influent, inhibiting filamentous growth. Plant performance controlling is presented in a logic flowchart in which operational parameters are linked to microbial manipulation, resulting in a useful tool for researchers and engineers.

  10. Stabilization of heavy metals in fired clay brick incorporated with wastewater treatment plant sludge: Leaching analysis

    Science.gov (United States)

    Kadir, A. A.; Hassan, M. I. H.; Salim, N. S. A.; Sarani, N. A.; Ahmad, S.; Rahmat, N. A. I.

    2018-04-01

    Wastewater treatment sludge or known as sewage sludge is regarded as the residue and produced by the sedimentation of the suspended solid during treatment at the wastewater treatment plant. As such, this sludge was gained from the separation process of the liquids and solids. This sludge wastes has becomes national issues in recent years due to the increasing amount caused by population and industrialization growth in Malaysia. This research was conducted to fully utilize the sludge that rich in dangerous heavy metals and at the same time act as low cost alternative materials in brick manufacturing. The investigation includes determination of heavy metal concentration and chemical composition of the sludge, physical and mechanical properties. Wastewater treatment sludge samples were collected from wastewater treatment plant located in Johor, Malaysia. X-Ray Fluorescence was conducted to determine the heavy metals concentration of wastewater treatment sludge. Different percentage of sludges which are 0%, 1%, 5%, 10%, and 20%, has been incorporated into fired clay brick. The leachability of heavy metals in fired clay brick that incorporated with sludge were determined by using Toxicity Characteristic Leaching Procedure (TCLP) and Synthetic Precipitation Leachability Procedure (SPLP) that has been analyzed by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results show a possibility to stabilize the heavy metals in fired clay brick incorporated with wastewater treatment sludge. 20% of the sludge incorporated into the brick is the most suitable for building materials as it leached less heavy metals concentration and complying with USEPA standard.

  11. "Dry-column" chromatography of plant pigments

    Science.gov (United States)

    Woeller, F. H.; Lehwalt, M. F.; Oyama, V. I.

    1973-01-01

    Separation of plant pigments which can be accomplished on thin-layer silica plates with mixture of petroleum ether, halocarbon, acetone, and polar solvent can be readily translated into dry-column technique that yields reproducible chromatograms after elution in fashion of liquid chromatography with fluorimeter as detector. Best solvent system was found to be mixture of petroleum ether, dichloromethane, acetone, and ethyl acetate.

  12. Emission of artificial sweeteners, select pharmaceuticals, and personal care products through sewage sludge from wastewater treatment plants in Korea.

    Science.gov (United States)

    Subedi, Bikram; Lee, Sunggyu; Moon, Hyo-Bang; Kannan, Kurunthachalam

    2014-07-01

    Concern over the occurrence of artificial sweeteners (ASWs) as well as pharmaceuticals and personal care products (PPCPs) in the environment is growing, due to their high use and potential adverse effects on non-target organisms. The data for this study are drawn from a nationwide survey of ASWs in sewage sludge from 40 representative wastewater treatment plants (WWTPs) that receive domestic (WWTPD), industrial (WWTPI), or mixed (domestic plus industrial; WWTPM) wastewaters in Korea. Five ASWs (concentrations ranged from 7.08 to 5220 ng/g dry weight [dw]) and ten PPCPs (4.95-6930 ng/g dw) were determined in sludge. Aspartame (concentrations ranged from 28.4 to 5220 ng/g dw) was determined for the first time in sewage sludge. The median concentrations of ASWs and PPCPs in sludge from domestic WWTPs were 0.8-2.5 and 1.0-3.4 times, respectively, the concentrations found in WWTPs that receive combined domestic and industrial wastewaters. Among the five ASWs analyzed, the median environmental emission rates of aspartame through domestic WWTPs (both sludge and effluent discharges combined) were calculated to be 417 μg/capita/day, followed by sucralose (117 μg/capita/day), acesulfame (90 μg/capita/day), and saccharin (66μg/capita/day). The per-capita emission rates of select PPCPs, such as antimicrobials (triclocarban: 158 μg/capita/day) and analgesics (acetaminophen: 59 μg/capita/day), were an order of magnitude higher than those calculated for antimycotic (miconazole) and anthelmintic (thiabendazole) drugs analyzed in this study. Multiple linear regression analysis of measured concentrations of ASWs and PPCPs in sludge revealed that several WWTP parameters, such as treatment capacity, population-served, sludge production rate, and hydraulic retention time could influence the concentrations found in sludge. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. The use of hazardous sludge solidification and green-lipped mussel shells in cementitious material: a case study of ngcc power plant of priok

    Directory of Open Access Journals (Sweden)

    Halim Samuel Dwima

    2018-01-01

    Full Text Available This paper aims to introduce the utilization of hazardous sludge with green-lipped mussel shells as concrete mixture components. The hazardous sludge is a side product of wastewater treatment plant operated in NGCC Priok, while green-lipped mussel shells are side product of community activity in Kalibaru, North Jakarta, Indonesia. Utilization is dedicated to preserve the environment, reducing both hazardous sludge generations from wastewater treatment plant and potential waste from social activities in the coastal area. Three different groups of concretes were prepared. The first group contains normal concretes with W/C ratio of 0.5. Subsequently, the second group contains concretes with dry sludge and mussel as a replacement of fine aggregate at different contents, 5% (C1, 10% (C2, and 15% (C3, with W/C ratio of 0.5. Finally, the last group contains concretes with dry sludge as cement replacement and the green-lipped mussel as fine aggregate replacement at different contents of 5% (C4, 10% (C5, and 15% (C6. The results show that dry sludge and green-lipped mussel provide better results when used as a substitute for fine aggregate rather than as cement replacement. In addition, the rate of strength development of concretes containing waste additions are slow compared to normal concretes.

  14. Optimization of the coke-oven activated sludge plants

    Energy Technology Data Exchange (ETDEWEB)

    Raizer Neto, Ernesto [Santa Catarina Univ., Florianopolis, SC (Brazil); Colin, Francois [Institut de Recherches Hydrologiques, 54 - Nancy (France); Prost, Christian [Laboratoire de Sciences de Genie Chimique, Nancy (France)

    1993-12-31

    In the coke-oven activated sludge plants one of the greatest problems of malfunction is due to inffluent variability. The composition and, or, concentration variations of the inffluent substrate, which can cause an unstable system, are function of the pollutant load. Nevertheless, the knowledge of the kinetic biodegradation of the coke-oven effluent represents the limiting factor to develop an effective biological treatment. This work describes a computational model of the biological treatment which was elaborated and validated from continuous pilot scale experiments and calibrated by comparing its predictions to the pilot experiment`s results. 12 refs., 9 figs., 3 tabs.

  15. Effects of Sludge Dry Solid Content and Residual Bulking Agents on Volatile Solids Reduction Using Eisenia foetida

    Directory of Open Access Journals (Sweden)

    Mohammad ali Abdoli

    2009-06-01

    Full Text Available In the first stage of this study, the compound effects of sludge dry solid content and residual bulking agent type (paper, saw dust, straw mixed with activated sludge (10, 15, and 20% dry solids on volatile solids (V.S. reduction were investigated using Eisenia foetida in pilot scale experiments with batches of fifty earthworms in each of the 10 experimental treatments over a period of 10 weeks. The maximum V.S. reduction was attained in the mixture of sludge and paper, with a D.S. of 15% (0.42 ± 0.03 % day-1 while the minimum V.S. reduction was achieved in the mixture of sludge and straw, with a D.S. of 10% (0.26 ± 0.01 % day-1. In the second stage, the survival of Eisenia foetida in the anaerobic sewage sludge was investigated. In the unmixed raw anaerobic sludge, all the earthworms died during the first 9 weeks of the study period due to acute toxicity. From week 10, however, their survival rate improved so that by week 12 when toxicity reduced to 25.40%, they completely survived. This is while in the mixture of anaerobic sludge with paper (D.S. 15%, 100% of the earthworms survived from week 8 after the volatile solids reduced to 20.42% and 17.40%.

  16. Parameter investigation for decentralised dewatering and solar thermic drying of sludge.

    Science.gov (United States)

    Wett, B; Demattio, M; Becker, W

    2005-01-01

    The purpose of this paper is an experimental and model assisted investigation of the capabilities of a dewatering system for sewage sludge for decentralised sites. Laboratory and field tests are performed with different initial conditions and the influences of filter medium, initial height, initial total suspended solids, temperature and relative humidity are discussed. The experimental work shows the feasibility of geotextile media for dewatering high water content sewage sludge and that the textile structure is of secondary importance. The specific filter resistance of the sludge cake is found to be the most significant factor in dewatering applications. The mathematical description of the dewatering process is based on the superposition of two models, the Conventional Filtration Theory for the filtration phase and the BT-model for the drying phase. Feasibility and limits of the theoretical approach are evaluated by means of a comparison between measurements and simulated data of cyclic reloading tests. It is found that a better filtration efficiency is achieved at higher TSS and at lower initial height of the slurry layer. Due to the viscosity decrease, a higher temperature enhances not only evaporation, but also filtration rate.

  17. The location and nature of accumulated phosphorus in seven sludges from activated sludge plants which exhibited enhanced phosphorus removal

    International Nuclear Information System (INIS)

    Buchan, L.

    1981-01-01

    Electron microscopy combined with the energy dispersive analysis of X-rays (EDX) has been used to examine the nature of the phosphorus accumulated in sludges from seven activated sludge plants exhibiting enhanced phosphorus removal. Large phosphorus accumulations were located in identical structures in the sludges examined. The phosphorus was located in large electron-dense bodies, within large bacterial cells which were characteristically grouped in clusters. The calcium:phosphorus ratio of these electron-dense bodies precluded them from being any form of calcium phosphate precipitate. Quantitative analysis indicated that the electron-dense bodies contained in excess of 30% phosphorus. The results obtained are supportive of a biological mechanism of enhanced phosphorus uptake in activated sludge

  18. Experience with a pilot plant for the irradiation of sewage sludge

    International Nuclear Information System (INIS)

    Suess, A.; Rosopulo, A.; Borchert, H.; Beck, T.; Bauchhenss, J.; Schurmann, G.

    1975-01-01

    Since hygienization of sewage sludge will be important for an agricultural application, it is necessary to study the effect of differently treated sewage sludge to plants and soil. In bean- and maize experiments in 1973 and 1974 it was found that treatment of sewage sludge is less important than soil properties and water capacity. Analysis on the efficiency of nutrients, minor elements and heavy metals from differently treated sewage sludge to plants were performed. Microbiological greenhouse studies indicated that there is a distinct tendency for different reactions that irradiated sewage sludge gives a slightly better effect than untreated one. In the field experiments there were nearly no differences between untreated and irradiated sewage sludge. Studies on soil fauna in the performed field trials indicate influences of abiotic factors on the different locations. Besides these influences there is a decrease of the number of Collemboles and Mites on the plots with 800 m 3 /ha treated sewage sludge. There is a remarkable high decrease in the plots with irradiated sewage sludge after an application of 800 m 3 /ha. Physical and chemical studies indicated, depending on the soil type, an increase in the effective field capacity after the application of sewage sludge, while there were sometimes the best effects with irradiated sewage sludge. Relative high aggregate values were observed in the plots with irradiated sewage sludge. (orig./MG) [de

  19. A Comparative Evaluation of Dried Activated Sludge and Mixed Dried Activated Sudge with Rice Husk silica to Remove Hydrogen Sulfide

    Directory of Open Access Journals (Sweden)

    Seyed Mahmoud Mehdinia

    2013-03-01

    Full Text Available The aim of this study was to investigate the effectiveness of dried activated sludge (DAS and mixed dried activated sludge with rice husk silica (DAS & RHS for removal of hydrogen sulfide (H2S. Two laboratory-scale filter columns (packed one litter were operated. Both systems were operated under different conditions of two parameters, namely different inlet gas concentrations and different inlet flow rates. The DAS & RHS packed filter showed more than 99.96% removal efficiency (RE with empty bed residence time (EBRT of 45 to 90 s and 300 mg/L inlet concentration of H2S. However, the RE decreased to 96.87% with the EBRT of 30 s. In the same condition, the DAS packed filter showed 99.37% RE. Nonetheless, the RE was shown to have dropped to 82.09% with the EBRT of 30 s. The maximum elimination capacity (EC was obtained in the DAS & RHS packed filter up to 52.32 g/m3h, with the RE of 96.87% and H2S mass loading rate of 54 g/m3h. The maximum EC in the DAS packed filter was obtained up to 44.33 g/m3h with the RE of 82.09% and the H2S mass loading rate of 54 g/m3h. After 53 days of operating time and 54 g/m3h of loading rates, the maximum pressure drop reached to 3.0 and 8.0 (mm H2O for the DAS & RHS packed and DAS packed filters, respectively. Based on the findings of this study, the DAS & RHS could be considered as a more suitable packing material to remove H2S.

  20. A key role for arbuscular mycorrhiza in plant acquisition of P from sewage sludge recycled to soil

    DEFF Research Database (Denmark)

    Mackay, Jessica E.; Cavagnaro, Timothy R.; Müller-Stöver, Dorette Sophie

    2017-01-01

    Dried and incinerated sewage sludge (SS) have the potential to be used as phosphorus (P) fertilisers. Arbuscular mycorrhizal fungi (AMF) contribute to plant P uptake; however, their role in P uptake from SS has yet to be fully explored. A compartmented pot system with an isotope pool dilution...... approach was used to investigate wheat (Triticum aestivum L.) P uptake from soluble P, dried SS and incinerated SS, via roots and/or AMF hyphae. Wheat was sown into an inner compartment containing a 33P label with/without AMF (Rhizophagus irregularis) inoculum. An outer soil compartment contained the P...

  1. Sewage sludge application in a plantation: effects on trace metal transfer in soil-plant-snail continuum.

    Science.gov (United States)

    Bourioug, Mohamed; Gimbert, Frédéric; Alaoui-Sehmer, Laurence; Benbrahim, Mohammed; Aleya, Lotfi; Alaoui-Sossé, Badr

    2015-01-01

    We studied the potential bioaccumulation of Cu, Zn, Pb and Cd by the snail Cantareus aspersus and evaluated the risk of leaching after application of sewage sludge to forest plantation ecosystems. Sewage sludge was applied to the soil surface at two loading rates (0, and 6 tons ha(-1) in dry matter) without incorporation into the soil so as to identify the sources of trace metal contamination in soil and plants and to evaluate effects on snail growth. The results indicated a snail mortality rate of less than 1% during the experiment, while their dry weight decreased significantly (snails showed no acute toxicity symptoms after soil amendment with sewage sludge over the exposure period considered. Additions of sewage sludge led to higher levels of trace metals in forest litter compared to control subplots, but similar trace metal concentrations were observed in sampling plants. Bioaccumulation study demonstrated that Zn had not accumulated in snails compared to Cu which accumulated only after 28 days of exposure to amended subplots. However, Pb and Cd contents in snails increased significantly after 14 and 28 days of exposure in both the control and amended subplots. At the last sampling date, in comparison to controls the Cd increase was higher in snails exposed to amended subplots. Thus, sludge spread therefore appears to be responsible for the observed bioaccumulation for Cu and Cd after 28days of exposure. Concerning Pb accumulation, the results from litter-soil-plant compartments suggest that soil is this metal's best transfer source. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Evaluating the stabilisation degree of digested sewage sludge: investigations at four municipal wastewater treatment plants.

    Science.gov (United States)

    Parravicini, V; Smidt, E; Svardal, K; Kroiss, H

    2006-01-01

    Further reduction of volatile suspended solids (VSS) during a post-stabilisation step was applied to evaluate the stabilisation degree of digested sewage sludge. For this purpose digested sludge was collected at four municipal wastewater treatment plants (WWTPs) and further stabilised in lab-scale chemostat reactors either under anaerobic or aerobic conditions. Experimental results showed that even in adequately digested sludge a consistent amount of VSS was degraded during aerobic post-stabilisation. It seems that aerobic conditions play a significant role during degradation of residual VSS. Additionally, specific VSS production (gVSS/peCOD110.d) as well as specific oxygen uptake rate were shown to be suitable parameters to assess the degree of sludge stabilisation at WWTPs. Fourier transform infrared spectroscopy was used to reveal changes in the sludge composition. Spectra of treated and untreated sludge samples indicated that the major component of residual VSS in stabilised sludge for instance consisted of biomass, while cellulose was absent.

  3. Characterization and constructive utilization of sludge produced in clari-flocculation unit of water treatment plant

    Science.gov (United States)

    Ahmad, Tarique; Ahmad, Kafeel; Alam, Mehtab

    2018-03-01

    All water treatment plants produce waste/residue amid the treatment of raw water. This study selectively investigates the clariflocculator sludge for its physicochemical characteristics and potential reuse options. Sieve analysis, XRF, SEM, XRD, FTIR, and TG-DTA instrumental techniques have been used to characterize the sludge sample. Results show that clariflocculator sludge contains about 78% fine sand having grain size range 150-75 μm. SiO2, Al2O3, Fe2O3 and CaO constitute the maximum percentage of chemical compounds present in the sludge and quartz is the main crystalline phase of the sludge. Recycling and reuse of this sludge, especially, as fine sand in preparing mortar, concrete mix and other civil engineering products would pave the way for constructive utilization with safe and sustainable sludge management strategies.

  4. Sludge dewatering and disposal practices for small activated sludge wastewater treatment plants.

    Science.gov (United States)

    Hatziconstantinou, G J; Efstathiou, H

    2003-01-01

    Sludge dewatering is a decisive step in the reduction of waste sludge volume, thus considerably affecting total sludge treatment and disposal costs. The construction of sludge dewatering facilities in small WwTPs though, is generally not cost effective. In this paper some experimental evidence is presented, that waste sludge dewatering in small WwTPs of the activated sludge extended aeration type, can be effectively achieved by a centrifuge type of equipment withdrawing sludge directly from the aeration tank; an economic evaluation of the possibility to employ a transportable type of similar equipment mounted on a truck, to serve a number of small WwTPs located in remote or isolated areas is also presented and discussed.

  5. Reasonable management plan of sludge in sewage disposal plant

    Energy Technology Data Exchange (ETDEWEB)

    Yum, Kyu Jin; Koo, Hyun Jung [Korea Environment Institute, Seoul (Korea)

    1998-12-01

    The compost method, which is widely used as a sewage disposal recycling in Korea, is now basically impossible to recycle sludge to compost by the Ministry of Agriculture and Forestry announcement. Therefore, the disposal of sludge will be much harder with reducing the amount of sludge used as compost. The amount of sludge other than using as compost is very small, so the development of various sludge recycling and use will be needed with regulations. This study was implemented to help the establishment of sewage sludge recycling policy in Korea. 30 refs., 17 figs., 58 tabs.

  6. Study of potential impacts of using sewage sludge in the amendment of desert reclaimed soil on wheat and jews mallow plants

    Directory of Open Access Journals (Sweden)

    Ahmed Mazen

    2010-08-01

    Full Text Available This investigation was conducted to study the impacts of using sewage sludge at different concentrations (0, 10, 25, 50, 75% in amendment of desert reclaimed soil properties and some physiological aspects in wheat and jews mallow plants. Generally adding sewage sludge to desert soil improved the soil texture, raised the organic matter contents, water holding capacity and lowered pH value. The contents of NPK gradually increased as the ratio of sewage sludge increased. The fresh and dry weights and biosyntheses of pigment contents of the variously treated test plants were increased by increasing the sewage sludge levels in the soil. Also, total carbohydrate and protein contents of sewage sludge-treated test plants were positively affected. With respect to the proline content and total free amino acids, in most cases, it decreased significantly, expect at 75% sewage sludge, which was higher than that of other concentrations. Also, the accumulation of metal was generally higher, especially in the root than that in the shoot system in the test plant tissues.

  7. Characteristics of ammonia emission during thermal drying of lime sludge for co-combustion in cement kilns.

    Science.gov (United States)

    Liu, Wei; Xu, Jingcheng; Liu, Jia; Cao, Haihua; Huang, Xiang-Feng; Li, Guangming

    2015-01-01

    Thermal drying was used to reduce sludge moisture content before co-combustion in cement kilns. The characteristics of ammonia (NH3) emission during thermal drying of lime sludge (LS) were investigated in a laboratory-scale tubular dry furnace under different temperature and time conditions. As the temperature increased, the NH3 concentration increased in the temperature range 100-130°C, decreased in the temperature range 130-220°C and increased rapidly at >220°C. Emission of NH3 also increased as the lime dosage increased and stabilized at lime dosages>5%. In the first 60 min of drying experiments, 55% of the NH3 was released. NH3 accounted for about 67-72% of the change in total nitrogen caused by the release of nitrogen-containing volatile compounds (VCs) from the sludge. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy revealed that the main forms of nitrogen in sludge were amides and amines. The addition of lime (CaO) could cause conversion of N-H, N-O or C-N containing compounds to NH3 during the drying process.

  8. GRANTING MYCORRHIZAL AND SLUDGE TO INCREASE PRODUCTION PLANT OF PEANUT (Arachis hypogaea L)

    OpenAIRE

    Hariani, Farida; ,, Erlita

    2016-01-01

    Giving mycorrhiza can improve nutrient uptake P plant, while Sludge can fertilize the soil. The use of organic fertilizer such as sludge has many benefits when applied in fertilizing agricultural crop land. The emphasis on the use of organic fertilizers continuously and sustainably will provide advantages and benefits in the long-term use. This study aimed to evaluate the response of groundnut crop production due to the provision of mycorrhizal and sludge as well as their interactions.The res...

  9. Sludge reduction in a small wastewater treatment plant by electro-kinetic disintegration.

    Science.gov (United States)

    Chiavola, Agostina; Ridolfi, Alessandra; D'Amato, Emilio; Bongirolami, Simona; Cima, Ennio; Sirini, Piero; Gavasci, Renato

    2015-01-01

    Sludge reduction in a wastewater treatment plant (WWTP) has recently become a key issue for the managing companies, due to the increasing constraints on the disposal alternatives. Therefore, all the solutions proposed with the aim of minimizing sludge production are receiving increasing attention and are tested either at laboratory or full-scale to evaluate their real effectiveness. In the present paper, electro-kinetic disintegration has been applied at full-scale in the recycle loop of the sludge drawn from the secondary settlement tank of a small WWTP for domestic sewage. After the disintegration stage, the treated sludge was returned to the biological reactor. Three different percentages (50, 75 and 100%) of the return sludge flow rate were subjected to disintegration and the effects on the sludge production and the WWTP operation efficiency evaluated. The long-term observations showed that the electro-kinetic disintegration was able to drastically reduce the amount of biological sludge produced by the plant, without affecting its treatment efficiency. The highest reduction was achieved when 100% return sludge flow rate was subjected to the disintegration process. The reduced sludge production gave rise to a considerable net cost saving for the company which manages the plant.

  10. SLUDGE TREATMENT PROJECT KOP DISPOSITION - THERMAL AND GAS ANALYSIS FOR THE COLD VACUUM DRYING FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    SWENSON JA; CROWE RD; APTHORPE R; PLYS MG

    2010-03-09

    The purpose of this document is to present conceptual design phase thermal process calculations that support the process design and process safety basis for the cold vacuum drying of K Basin KOP material. This document is intended to demonstrate that the conceptual approach: (1) Represents a workable process design that is suitable for development in preliminary design; and (2) Will support formal safety documentation to be prepared during the definitive design phase to establish an acceptable safety basis. The Sludge Treatment Project (STP) is responsible for the disposition of Knock Out Pot (KOP) sludge within the 105-K West (KW) Basin. KOP sludge consists of size segregated material (primarily canister particulate) from the fuel and scrap cleaning process used in the Spent Nuclear Fuel process at K Basin. The KOP sludge will be pre-treated to remove fines and some of the constituents containing chemically bound water, after which it is referred to as KOP material. The KOP material will then be loaded into a Multi-Canister Overpack (MCO), dried at the Cold Vacuum Drying Facility (CVDF) and stored in the Canister Storage Building (CSB). This process is patterned after the successful drying of 2100 metric tons of spent fuel, and uses the same facilities and much of the same equipment that was used for drying fuel and scrap. Table ES-l present similarities and differences between KOP material and fuel and between MCOs loaded with these materials. The potential content of bound water bearing constituents limits the mass ofKOP material in an MCO load to a fraction of that in an MCO containing fuel and scrap; however, the small particle size of the KOP material causes the surface area to be significantly higher. This relatively large reactive surface area represents an input to the KOP thermal calculations that is significantly different from the calculations for fuel MCOs. The conceptual design provides for a copper insert block that limits the volume available to

  11. Gasification of a Dried Sewage Sludge in a Laboratory Scale Fixed Bed Reactor

    Directory of Open Access Journals (Sweden)

    Sebastian Werle

    2015-08-01

    Full Text Available This paper presents an investigation of sewage sludge gasification in a fixed bed gasifier. Experiments were conducted on a laboratory scale fixed bed gasifier. In the experiments, two types of dried sewage sludge were tested and their properties were analysed. Parameters such as air ratio λ = 0.12 to 0.27, gasification agent temperature t = 50 to 250 °C and gasification agent composition ( = 0.21 and  > 0.21 were found to influence on temperature distribution, syngas Lower Heating Value (LHV and syngas composition. The results indicate that the syngas LHV was found to decrease with increased air ratio for all analyzed cases: cold and preheated air and cold enriched air. The increase in the percentage of the main combustible components was accompanied by a decrease in the concentration of carbon dioxide. Increasing oxygen concentration increased the temperature, which tended to favor the formation of smaller molecules in the gas mixture. Thus, the enriched air medium produced a gas with a higher LHV. In contrast to conventional gasification, gasification process with gasification agent preheating causes that the flux of heat necessary to support endothermic gasification reactions is producing more effective. Air preheating causes increases hydrogen and carbon monoxide production.

  12. Thermo-Oxidization of Municipal Wastewater Treatment Plant Sludge for Production of Class A Biosolids

    Science.gov (United States)

    Bench-scale reactors were used to test a novel thermo-oxidation process on municipal wastewater treatment plant (WWTP) waste activated sludge (WAS) using hydrogen peroxide (H2O2) to achieve a Class A sludge product appropriate for land application. Reactor ...

  13. Application of waterworks sludge in wastewater treatment plants

    DEFF Research Database (Denmark)

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

    2013-01-01

    in pH due to the produced alkalinity from dissolution of iron(III)hydroxides from waterworks sludge, lower internal recirculation of phosphate concentration in the reject water and reduced sulphide in the digested liquid. However, recirculation of the produced soluble iron(II) as an iron source......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...... water and commercial iron solution was successful in dissolving the iron from waterworks sludge. The anaerobic dissolution of waterworks sludge due to co-digestion with biological sludge (primary and biological activated sludge) resulted in reduction of iron, increase in dissolved iron(II), increase...

  14. Evaluation of Pathogen Removal in a Solar Sludge Drying Facility Using Microbial Indicators

    Directory of Open Access Journals (Sweden)

    D. İpek Kurtböke

    2010-02-01

    Full Text Available South East Queensland is one of the fastest growing regions in Australia with a correspondingly rapid increase in sewage production. In response, local councils are investing in more effective and sustainable options for the treatment and reuse of domestic and industrial effluents. A novel, evaporative solar dryer system has been installed on the Sunshine Coast to convert sewage sludge into a drier, usable form of biosolids through solar radiation exposure resulting in decreased moisture concentration and pathogen reduction. Solar-dried biosolids were analyzed for selected pathogenic microbial, metal and organic contaminants at the end of different drying cycles in a collaborative study conducted with the Regional Council. Although fecal coliforms were found to be present, enteroviruses, parasites, E. coli, and Salmonella sp. were not detected in the final product. However, elevated levels of zinc and copper were still present which restricted public use of the biosolids. Dilution of the dried biosolids with green waste as well as composting of the biosolids is likely to lead to the production of an environmentally safe, Class A end-product.

  15. Evaluation of pathogen removal in a solar sludge drying facility using microbial indicators.

    Science.gov (United States)

    Shanahan, Emily F; Roiko, Anne; Tindale, Neil W; Thomas, Michael P; Walpole, Ronald; Kurtböke, D Ipek

    2010-02-01

    South East Queensland is one of the fastest growing regions in Australia with a correspondingly rapid increase in sewage production. In response, local councils are investing in more effective and sustainable options for the treatment and reuse of domestic and industrial effluents. A novel, evaporative solar dryer system has been installed on the Sunshine Coast to convert sewage sludge into a drier, usable form of biosolids through solar radiation exposure resulting in decreased moisture concentration and pathogen reduction. Solar-dried biosolids were analyzed for selected pathogenic microbial, metal and organic contaminants at the end of different drying cycles in a collaborative study conducted with the Regional Council. Although fecal coliforms were found to be present, enteroviruses, parasites, E. coli, and Salmonella sp. were not detected in the final product. However, elevated levels of zinc and copper were still present which restricted public use of the biosolids. Dilution of the dried biosolids with green waste as well as composting of the biosolids is likely to lead to the production of an environmentally safe, Class A end-product.

  16. System for the Reduction of Substances in Reject Water from Reed-Bed Sludge Mineralization Plants

    DEFF Research Database (Denmark)

    2004-01-01

    the reject water via recirculation into a mixed reactor and back onto the reed-beds. The mixed rector consists of a container in which sludge (that is typically loaded directly on to reed-beds) is mixed with recirculated reject water from reed-beds. The sludge mixture has a definable hydraulic retention time...... within the container. The solution is then applied to the reed-beds, which dewaters, converts, and partially mineralize the sludge mixture. The reject water from the reed-beds is split where up to100% of the reject water is recirculated back to the mixed reactor and the remaining usually disposed......The invention is a system for the reduction of substances in reject water from reed-bed sludge mineralization plants (also referred to as sludge dewatering reed-beds). The systems utilizes the composition of substances in reject water from reed-beds and that of sludge to reduce substance mass from...

  17. Sewage sludge conditioning with the application of ash from biomass-fired power plant

    Science.gov (United States)

    Wójcik, Marta; Stachowicz, Feliks; Masłoń, Adam

    2018-02-01

    During biomass combustion, there are formed combustion products. Available data indicates that only 29.1 % of biomass ashes were recycled in Poland in 2013. Chemical composition and sorptive properties of ashes enable their application in the sewage sludge treatment. This paper analyses the impact of ashes from biomass-combustion power plant on sewage sludge dewatering and higienisation. The results obtained in laboratory tests proved the possitive impact of biomass ashes on sewage sludge hydration reduction after dewatering and the increase of filtrate volume. After sludge conditioning with the use of biomass combustion by-products, the final moisture content decreased by approximatelly 10÷25 % in comparison with raw sewage sludge depending on the method of dewatering. The application of biomass combustion products in sewage sludge management could provide an alternative method of their utilization according to law and environmental requirements.

  18. Feasibility analysis of a sewage sludge treatment by an irradiation plant in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, J.; Balcazar, M. [Instituto Nacional de Investigaciones Nucleares, Km. 36.5 Carretera Mexico-Toluca, C.P. 52045 Estado de Mexico (Mexico); Colin, A. [Universidad Autonoma del Estado de Mexico, Toluca (Mexico); Tavera, L. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152, 07730 Mexico D.F. (Mexico)

    2002-07-01

    Technical and economic analyses of an irradiation plant for sewage sludge treatment determined that an appropriate place for the first sludge electron irradiator in Mexico would be the sewage water treatment plant located north of Toluca in the State of Mexico. This treatment plant is mainly used for domestic wastewater and produces an approximate volume of 70 ton d-] liquid sewage sludge. Considering a 50 k W power of a 10 MeV electron linear accelerator, an irradiation dose of S KGy and a treatment capacity of 346 tons per day, it is estimated that the treatment cost would be of $9.00 US dollars per ton. (Author)

  19. Feasibility analysis of a sewage sludge treatment by an irradiation plant in Mexico

    CERN Document Server

    Moreno, J; Colin, A; Tavera, L

    2002-01-01

    Technical and economic analyses of an irradiation plant for sewage sludge treatment determined that an appropriate place for the first sludge electron irradiator in Mexico would be the sewage water treatment plant located north of Toluca in the State of Mexico. This treatment plant is mainly used for domestic wastewater and produces an approximate volume of 70 ton d-] liquid sewage sludge. Considering a 50 k W power of a 10 MeV electron linear accelerator, an irradiation dose of S KGy and a treatment capacity of 346 tons per day, it is estimated that the treatment cost would be of $9.00 US dollars per ton. (Author)

  20. Effects of sewage sludge on Di-(2-ethylhexyl) phthalate uptake by plants

    International Nuclear Information System (INIS)

    Aranda, J.M.; O'Connor, G.A.; Eiceman, G.A.

    1989-01-01

    Di-(2-ethylhexyl) phthalate (DEHP) is a priority organic pollutant frequently found in municipal sludges. A greenhouse study was conducted to determine the effect of sludge on plant uptake of 14 C-DEHP (carbonyl labeled). Plants grown included three food chain crops, lettuce (Lactuca sativa L.), carrot (Daucus carota L.) and chile pepper (Capsicum annuum L.) and tall fescue (Festuca arundinacea Schreb.). Net 14 C concentration in plants grown in soil amended with 14 C-DEHP-contaminated sludge was independent of sludge rate (at the same DEHP loading) for lettuce, chile fruit, and carrot roots. Net 14 C concentration, however, was inversely related to sludge rate in carrot tops, fescue, and chile plants. Intact DEHP was not detected in plants by gas chromatography/mass spectrometry analysis. Calculated plant DEHP concentrations (based on measured net 14 C concentrations and DEHP specific activities) were generally correlated better with DEHP soil solution concentrations than with total DEHP soil concentrations. Net 14 C-DEHP bioconcentration factors were calculated from initial soil DEHP concentration and plant fresh weights. Bioconcentration factors ranged from 0.01 to 0.03 for fescue, lettuce, carrots, and chile, suggesting little DEHP uptake. Additionally, because intact DEHP was not detected in any plants, DEHP uptake by plants was of minor importance and would not limit sludge additions to soils used to grow these crops

  1. Drying Without Senescence in Resurrection Plants

    Directory of Open Access Journals (Sweden)

    Cara Ashleigh Griffiths

    2014-02-01

    Full Text Available Research into extreme drought tolerance in resurrection plants using species such as Craterostigma plantagineum, Craterostigma wilmsii, Xerophyta humilis, Tortula ruralis and Sporobolus stapfianus has provided some insight into the desiccation tolerance mechanisms utilized by these plants to allow them to persist under extremely adverse environmental conditions. Some of the mechanisms used to ensure cellular preservation during severe dehydration appear to be peculiar to resurrection plants. Apart from the ability to preserve vital cellular components during drying and rehydration, such mechanisms include the ability to down-regulate growth-related metabolism rapidly in response to changes in water availability, and the ability to inhibit dehydration-induced senescence programs enabling reconstitution of photosynthetic capacity quickly following a rainfall event. Currently, very little is known about the molecular mechanisms that resurrection plants employ to avoid undergoing drought-related senescence during the desiccation process. To survive desiccation, dehydration in the perennial resurrection grass S. stapfianus must proceed slowly over a period of 7 days or more. Leaves detached from the plant before 60% relative water content (RWC is attained are desiccation-sensitive indicating that desiccation tolerance is conferred in vegetative tissue of S. stapfianus when the leaf RWC has declined to 60%. Whilst some older leaves remaining attached to the plant during dehydration will senesce, suggesting dehydration-induced senescence may be influenced by leaf age or the rate of dehydration in individual leaves, the majority of leaves do not senesce. Rather these leaves dehydrate to air-dryness and revive fully following rehydration. Hence it seems likely that there are genes expressed in younger leaf tissues of resurrection plants that enable suppression of drought-related senescence pathways. As very few studies have directly addressed this

  2. Fate of cyanobacteria in drinking water treatment plant lagoon supernatant and sludge

    Energy Technology Data Exchange (ETDEWEB)

    Pestana, Carlos J.; Reeve, Petra J.; Sawade, Emma [Australian Water Quality Centre, South Australian Water Corporation, Adelaide, SA 5000 (Australia); Voldoire, Camille F. [Australian Water Quality Centre, South Australian Water Corporation, Adelaide, SA 5000 (Australia); École Européenne de Chimie, Polymères et Matériaux (ECPM), Strasbourg 67087 (France); Newton, Kelly; Praptiwi, Radisti [Australian Water Quality Centre, South Australian Water Corporation, Adelaide, SA 5000 (Australia); Collingnon, Lea [Australian Water Quality Centre, South Australian Water Corporation, Adelaide, SA 5000 (Australia); École Européenne de Chimie, Polymères et Matériaux (ECPM), Strasbourg 67087 (France); Dreyfus, Jennifer [Allwater, Adelaide Services Alliance, Wakefield St, Adelaide, SA 5001 (Australia); Hobson, Peter [Australian Water Quality Centre, South Australian Water Corporation, Adelaide, SA 5000 (Australia); Gaget, Virginie [University of Adelaide, Ecology and Environmental Sciences, School of Biological Sciences, Adelaide, SA 5005 (Australia); Newcombe, Gayle, E-mail: gayle.newcombe@sawater.com.au [Australian Water Quality Centre, South Australian Water Corporation, Adelaide, SA 5000 (Australia)

    2016-09-15

    In conventional water treatment processes, where the coagulation and flocculation steps are designed to remove particles from drinking water, cyanobacteria are also concentrated into the resultant sludge. As a consequence, cyanobacteria-laden sludge can act as a reservoir for metabolites such as taste and odour compounds and cyanotoxins. This can pose a significant risk to water quality where supernatant from the sludge treatment facility is returned to the inlet to the plant. In this study the complex processes that can take place in a sludge treatment lagoon were investigated. It was shown that cyanobacteria can proliferate in the conditions manifest in a sludge treatment lagoon, and that cyanobacteria can survive and produce metabolites for at least 10 days in sludge. The major processes of metabolite release and degradation are very dependent on the physical, chemical and biological environment in the sludge treatment facility and it was not possible to accurately model the net effect. For the first time evidence is provided to suggest that there is a greater risk associated with recycling sludge supernatant than can be estimated from the raw water quality, as metabolite concentrations increased by up to 500% over several days after coagulation, attributed to increased metabolite production and/or cell proliferation in the sludge. - Highlights: • Cyanobacteria in water treatment sludge significantly impact supernatant quality • Cyanobacteria can survive, and thrive, in sludge lagoon supernatant and in treatment sludge • Metabolite concentrations in cyanobacteria in sludge can increase up to 500% • The risk associated with supernatant recycling was assessed relative to available treatment barriers.

  3. Fate of cyanobacteria in drinking water treatment plant lagoon supernatant and sludge

    International Nuclear Information System (INIS)

    Pestana, Carlos J.; Reeve, Petra J.; Sawade, Emma; Voldoire, Camille F.; Newton, Kelly; Praptiwi, Radisti; Collingnon, Lea; Dreyfus, Jennifer; Hobson, Peter; Gaget, Virginie; Newcombe, Gayle

    2016-01-01

    In conventional water treatment processes, where the coagulation and flocculation steps are designed to remove particles from drinking water, cyanobacteria are also concentrated into the resultant sludge. As a consequence, cyanobacteria-laden sludge can act as a reservoir for metabolites such as taste and odour compounds and cyanotoxins. This can pose a significant risk to water quality where supernatant from the sludge treatment facility is returned to the inlet to the plant. In this study the complex processes that can take place in a sludge treatment lagoon were investigated. It was shown that cyanobacteria can proliferate in the conditions manifest in a sludge treatment lagoon, and that cyanobacteria can survive and produce metabolites for at least 10 days in sludge. The major processes of metabolite release and degradation are very dependent on the physical, chemical and biological environment in the sludge treatment facility and it was not possible to accurately model the net effect. For the first time evidence is provided to suggest that there is a greater risk associated with recycling sludge supernatant than can be estimated from the raw water quality, as metabolite concentrations increased by up to 500% over several days after coagulation, attributed to increased metabolite production and/or cell proliferation in the sludge. - Highlights: • Cyanobacteria in water treatment sludge significantly impact supernatant quality • Cyanobacteria can survive, and thrive, in sludge lagoon supernatant and in treatment sludge • Metabolite concentrations in cyanobacteria in sludge can increase up to 500% • The risk associated with supernatant recycling was assessed relative to available treatment barriers

  4. Hydrothermal Liquefaction and Upgrading of Municipal Wastewater Treatment Plant Sludge: A Preliminary Techno-Economic Analysis, Rev.1

    Energy Technology Data Exchange (ETDEWEB)

    Snowden-Swan, Lesley J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhu, Yunhua [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Susanne B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elliott, Douglas C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schmidt, Andrew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hallen, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billing, Justin M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Todd R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fox, Samuel P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Maupin, Gary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-01

    A preliminary process model and techno-economic analysis (TEA) was completed for fuel produced from hydrothermal liquefaction (HTL) of sludge waste from a municipal wastewater treatment plant (WWTP) and subsequent biocrude upgrading. The model is adapted from previous work by Jones et al. (2014) for algae HTL, using experimental data generated in fiscal year 2015 (FY15) bench-scale HTL testing of sludge waste streams. Testing was performed on sludge samples received from Metro Vancouver’s Annacis Island WWTP (Vancouver, B.C.) as part of a collaborative project with the Water Environment and Reuse Foundation (WERF). The full set of sludge HTL testing data from this effort will be documented in a separate report to be issued by WERF. This analysis is based on limited testing data and therefore should be considered preliminary. In addition, the testing was conducted with the goal of successful operation, and therefore does not represent an optimized process. Future refinements are necessary to improve the robustness of the model, including a cross-check of modeled biocrude components with the experimental GCMS data and investigation of equipment costs most appropriate at the relatively small scales used here. Environmental sustainability metrics analysis is also needed to understand the broader impact of this technology pathway. The base case scenario for the analysis consists of 10 HTL plants, each processing 100 dry U.S. ton/day (92.4 ton/day on a dry, ash-free basis) of sludge waste and producing 234 barrel per stream day (BPSD) biocrude, feeding into a centralized biocrude upgrading facility that produces 2,020 barrel per standard day of final fuel. This scale was chosen based upon initial wastewater treatment plant data collected by PNNL’s resource assessment team from the EPA’s Clean Watersheds Needs Survey database (EPA 2015a) and a rough estimate of what the potential sludge availability might be within a 100-mile radius. In addition, we received

  5. Re-use of drinking water treatment plant (DWTP) sludge: Characterization and technological behaviour of cement mortars with atomized sludge additions

    International Nuclear Information System (INIS)

    Husillos Rodriguez, N.; Martinez Ramirez, S.; Blanco Varela, M.T.; Guillem, M.; Puig, J.; Larrotcha, E.; Flores, J.

    2010-01-01

    This paper aims to characterize spray-dried DWTP sludge and evaluate its possible use as an addition for the cement industry. It describes the physical, chemical and micro-structural characterization of the sludge as well as the effect of its addition to Portland cements on the hydration, water demand, setting and mechanical strength of standardized mortars. Spray drying DWTP sludge generates a readily handled powdery material whose particle size is similar to those of Portland cement. The atomized sludge contains 12-14% organic matter (mainly fatty acids), while its main mineral constituents are muscovite, quartz, calcite, dolomite and seraphinite (or clinoclor). Its amorphous material content is 35%. The mortars were made with type CEM I Portland cement mixed with 10 to 30% atomized sludge exhibited lower mechanical strength than the control cement and a decline in slump. Setting was also altered in the blended cements with respect to the control.

  6. Wastewater Sludge Stabilization Using Lime A Case Study of West Ahwaz Wastewater Treatment Plant

    Directory of Open Access Journals (Sweden)

    Mehdi Farzadkia

    2009-01-01

    Full Text Available Lime stabilization is a chemical method used for wastewater sludge stabilization. It is capable of decreasing large quantities of pathogens and of preventing microbial degradation of sludge organic materials. The main objective of the present experimental research was to investigate stabilization of the sludge from west Ahwaz wastewater treatment plant by lime addition and to control if the microbial quality of this sludge conforms to the USEPA standards for sludge reuse and safe disposal. The study was carried out on a pilot scale in 5 stages over a period of 12 months (July 2005 to June 2006 at west Ahwaz wastewater treatment plant laboratory using raw sludge. For the purposes of this study, a 30-liter reactor was commissioned and loaded with sludge and appropriate quantities of hydrated lime were added based on the solid waste percent. The parameters used to determine stabilization efficiency were pH, Total Coliform, Fecal Coliform, and parasite eggs. The results showed that lime addition at a ratio of 265g Ca(OH2/kg. ds was the optimum level for sludge stabilization in westAhwazwastewater treatment plant, which is acceptable from both economic and technical viewpoints. The method is capable of achieving class B but never satisfied class A of USEPA standards.

  7. Plant dried powders as biocatalysts: Hydrolysis of 1- phenylpropanol ...

    African Journals Online (AJOL)

    Plant dried powders as biocatalysts: Hydrolysis of 1- phenylpropanol acetate. A Solís, HI Pérez, N Manjarrez, H Luna, J Cassani, LE Bernaldez, A Hernández. Abstract. The hydrolytic ability of plant dried powders, lyophilized or acetone dried, was tested on the hydrolysis of racemic 1-phenylpropanol acetate. Most of the ...

  8. Growth of plants on TBT-contaminated harbour sludge and effect on TBT removal.

    Science.gov (United States)

    Novak, Jana; Trapp, Stefan

    2005-11-01

    Worldwide, large amounts of sediments have to be dredged annually from waterways and harbours. These sediments are sometimes polluted with a variety of toxic compounds. In some countries, including Belgium, the load with the biocide tributyltin (TBT) from ship coatings prohibits the dumping of harbour sludge into the sea. Land-based dumping is a commonly used alternative. This research investigated the feasibility to use land-deposited harbour sludge for plant production. In a field trial, the growth of 38 more or less salt-tolerant plant species on low and high TBT-contaminated sediments was studied. The elimination of TBT from sludge with and without vegetation was compared. The uptake of TBT and its degradation products di- and monobutyltin (DBT and MBT) into harvest products under field conditions was determined. EXPERIMENTAL SET-UP: Sediments dredged in May 2003 from the brackish waters of the port of Antwerp were analysed in the laboratory for soil texture, pH, electroconductivity, sodium, magnesium, potassium, calcium, ammonium, nitrate, total nitrogen, chloride, sulphur and the organotins TBT, DBT and MBT. The sediments were lagooned for one year to dewater, desalinate and improve their structure. Salt-tolerant domestic and wild plants were selected and sown in May 2004. In August 2004, plants were harvested and the produced biomass was determined. Samples were taken from vegetated and non-vegetated top and bottom sediments and from plants growing above soil and analysed for TBT, DBT and MBT. The fresh sediments showed a good supply with nutrients and a neutral pH, but were rather saline (EC 14 mS cm(-1) of the saturated paste extract). The salinity decreased to 3.7 mS cm(-1) during lagoonation. The high and the low contaminated sediment had initially 43 and 1.6 mg TBT kg(-1) dry weight, respectively. Besides TBT, several other contaminants were present in the sediments at critical levels. The biomass production of the plant species from the field trial

  9. Drying without senescence in resurrection plants

    Science.gov (United States)

    Griffiths, Cara A.; Gaff, Donald F.; Neale, Alan D.

    2014-01-01

    Research into extreme drought tolerance in resurrection plants using species such as Craterostigma plantagineum, C. wilmsii, Xerophyta humilis, Tortula ruralis, and Sporobolus stapfianus has provided some insight into the desiccation tolerance mechanisms utilized by these plants to allow them to persist under extremely adverse environmental conditions. Some of the mechanisms used to ensure cellular preservation during severe dehydration appear to be peculiar to resurrection plants. Apart from the ability to preserve vital cellular components during drying and rehydration, such mechanisms include the ability to down-regulate growth-related metabolism rapidly in response to changes in water availability, and the ability to inhibit dehydration-induced senescence programs enabling reconstitution of photosynthetic capacity quickly following a rainfall event. Extensive research on the molecular mechanism of leaf senescence in non-resurrection plants has revealed a multi-layered regulatory network operates to control programed cell death pathways. However, very little is known about the molecular mechanisms that resurrection plants employ to avoid undergoing drought-related senescence during the desiccation process. To survive desiccation, dehydration in the perennial resurrection grass S. stapfianus must proceed slowly over a period of 7 days or more. Leaves detached from the plant before 60% relative water content (RWC) is attained are desiccation-sensitive indicating that desiccation tolerance is conferred in vegetative tissue of S. stapfianus when the leaf RWC has declined to 60%. Whilst some older leaves remaining attached to the plant during dehydration will senesce, suggesting dehydration-induced senescence may be influenced by leaf age or the rate of dehydration in individual leaves, the majority of leaves do not senesce. Rather these leaves dehydrate to air-dryness and revive fully following rehydration. Hence it seems likely that there are genes expressed in

  10. Estimates of Radiation Dose Rates Near Large Diameter Sludge Containers in T Plant

    CERN Document Server

    Himes, D A

    2002-01-01

    Dose rates in T Plant canyon during the handling and storage of large diameter storage containers of K Basin sludge were estimated. A number of different geometries were considered from which most operational situations of interest can be constructed.

  11. Water Treatment Plant Sludges--An Update of the State of the Art: Part 2.

    Science.gov (United States)

    American Water Works Association Journal, 1978

    1978-01-01

    This report outlines the state of the art with respect to nonmechanical and mechanical methods of dewatering water treatment plant sludge, ultimate solids disposal, and research and development needs. (CS)

  12. Fate of cyanobacteria in drinking water treatment plant lagoon supernatant and sludge.

    Science.gov (United States)

    Pestana, Carlos J; Reeve, Petra J; Sawade, Emma; Voldoire, Camille F; Newton, Kelly; Praptiwi, Radisti; Collingnon, Lea; Dreyfus, Jennifer; Hobson, Peter; Gaget, Virginie; Newcombe, Gayle

    2016-09-15

    In conventional water treatment processes, where the coagulation and flocculation steps are designed to remove particles from drinking water, cyanobacteria are also concentrated into the resultant sludge. As a consequence, cyanobacteria-laden sludge can act as a reservoir for metabolites such as taste and odour compounds and cyanotoxins. This can pose a significant risk to water quality where supernatant from the sludge treatment facility is returned to the inlet to the plant. In this study the complex processes that can take place in a sludge treatment lagoon were investigated. It was shown that cyanobacteria can proliferate in the conditions manifest in a sludge treatment lagoon, and that cyanobacteria can survive and produce metabolites for at least 10days in sludge. The major processes of metabolite release and degradation are very dependent on the physical, chemical and biological environment in the sludge treatment facility and it was not possible to accurately model the net effect. For the first time evidence is provided to suggest that there is a greater risk associated with recycling sludge supernatant than can be estimated from the raw water quality, as metabolite concentrations increased by up to 500% over several days after coagulation, attributed to increased metabolite production and/or cell proliferation in the sludge. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. The effect of sludge water treatment plant residuals on the properties of compressed brick

    Science.gov (United States)

    Shamsudin, Shamrul-Mar; Shahidan, S.; Azmi, M. A. M.; Ghaffar, S. A.; Ghani, M. B. Abdul; Saiful Bahari, N. A. A.; Zuki, S. S. M.

    2017-11-01

    The focus of this study is on the production of compressed bricks which contains sludge water treatment plant (SWTP) residuals obtained from SAJ. The main objective of this study is to utilise and incorporate discarded material (SWTP) in the form of residual solution to produce compressed bricks. This serves as one of the recycling efforts to conserve the environment. This study determined the optimum mix based on a mix ratio of 1:2:4 (cement: sand: soil) in the production of compressed bricks where 5 different mixes were investigated i. e. 0%, 5%, 10%, 20%, and 30% of water treatment plant residue solution. The production of the compressed bricks is in accordance with the Malaysian Standard MS 7.6: 1972 and British Standard BS 3921: 1985 - Compressive Strength & Water Absorption. After being moulded and air dried, the cured bricks were subjected to compression tests and water absorption tests. Based on the tests conducted, it was found that 20% of water treatment plant residue solution which is equivalent to 50% of soil content replacement with a mix composition of [10: cement] [20: sand] [20: soil] [20: water treatment plant residue solution] is the optimum mix. It was also observed that the bricks containing SWTP residuals were lighter in weight compared to the control specimens

  14. STP-ECRTS - THERMAL AND GAS ANALYSES FOR SLUDGE TRANSPORT AND STORAGE CONTAINER (STSC) STORAGE AT T PLANT

    Energy Technology Data Exchange (ETDEWEB)

    CROWE RD; APTHORPE R; LEE SJ; PLYS MG

    2010-04-29

    The Sludge Treatment Project (STP) is responsible for the disposition of sludge contained in the six engineered containers and Settler tank within the 105-K West (KW) Basin. The STP is retrieving and transferring sludge from the Settler tank into engineered container SCS-CON-230. Then, the STP will retrieve and transfer sludge from the six engineered containers in the KW Basin directly into a Sludge Transport and Storage Containers (STSC) contained in a Sludge Transport System (STS) cask. The STSC/STS cask will be transported to T Plant for interim storage of the STSC. The STS cask will be loaded with an empty STSC and returned to the KW Basin for loading of additional sludge for transportation and interim storage at T Plant. CH2MHILL Plateau Remediation Company (CHPRC) contracted with Fauske & Associates, LLC (FAI) to perform thermal and gas generation analyses for interim storage of STP sludge in the Sludge Transport and Storage Container (STSCs) at T Plant. The sludge types considered are settler sludge and sludge originating from the floor of the KW Basin and stored in containers 210 and 220, which are bounding compositions. The conditions specified by CHPRC for analysis are provided in Section 5. The FAI report (FAI/10-83, Thermal and Gas Analyses for a Sludge Transport and Storage Container (STSC) at T Plant) (refer to Attachment 1) documents the analyses. The process considered was passive, interim storage of sludge in various cells at T Plant. The FATE{trademark} code is used for the calculation. The results are shown in terms of the peak sludge temperature and hydrogen concentrations in the STSC and the T Plant cell. In particular, the concerns addressed were the thermal stability of the sludge and the potential for flammable gas mixtures. This work was performed with preliminary design information and a preliminary software configuration.

  15. Hydrogen-rich gas production via fast pyrolysis of biophysical dried sludge: Effect of particle size and moisture content on product yields and syngas composition.

    Science.gov (United States)

    Han, Rong; Liu, Jinwen; Zhao, Chenxi; Li, Yuliang; Chen, Aixia

    2016-06-01

    After biophysical drying, a novel biophysical dried sludge particle was obtained. This work aims to investigate the function and effects of particle sizes and moisture contents on the fast pyrolysis of biophysical dried sludge particles. The results showed that large particles (>4 mm) favoured the oil generation with a maximum value of 19.0%, and small particles (syngas production and induced higher H2 and CO emission, owing to the well-developed microstructure, enrichment of cellulose, and enhanced catalytic effects during the charring process. The introduction of proper moisture content (53.9% to 62.6%) to biophysical dried sludge was found to dramatically enhance syngas yield, hydrogen production, and carbon conversion efficiency. H2 molar concentration reached a maximum of 46.02% at a moisture content of 53.9%, which was attributed to the steam reforming and steam gasification accompanying the initial biophysical dried sludge pyrolysis. © The Author(s) 2016.

  16. Effects of aeration on matrix temperature by infrared thermal imager and computational fluid dynamics during sludge bio-drying.

    Science.gov (United States)

    Yu, Dawei; Yang, Min; Qi, Lu; Liu, Mengmeng; Wang, Yawei; Wei, Yuansong

    2017-10-01

    The effect of aeration on the pile matrix temperature was investigated using thermocouples and Infrared Thermal Imager (IRI) for temperature sensing, and Computational Fluid Dynamics (CFD) for modelling of temperature variation during aeration in a full-scale sludge biodrying plant. With aeration saving of 20%, the improved strategy speeded up biodrying from 21 days to 14 days, while achieving similar drying effect. A persistent thermocouple recorded the one-dimensional (1D) total temperature variation of all aeration strategies. The IRI captured the rapid two-dimensional (2D) pile temperature dropped from 72.5 °C to 30.3 °C during 6 min of aeration, which mechanism suggested as the latent heat of moisture evaporation and sensible heat of air exchange. The CFD three-dimensional (3D) CFD results highlight the importance of latent heat rather than sensible heat. Therefore, the pile temperature drop inferred is ΔT = 5.38 °C theoretically and ΔT = 5.17 ± 4.56 °C practically, per unit of MC removed. These findings also emphasize the possibility of a pile temperature valley, due to excessive aeration under unsaturated vapour conditions. Surface temperature monitored by IRI coupled with 3D temperature simulated by CFD rapidly gives a clear matrix temperature evolution, empowering biodrying by more accurate temperature and aeration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Improving biogas production from anaerobic co-digestion of sewage sludge with a thermal dried mixture of food waste, cheese whey and olive mill wastewater.

    Science.gov (United States)

    Maragkaki, A E; Vasileiadis, I; Fountoulakis, M; Kyriakou, A; Lasaridi, K; Manios, T

    2018-01-01

    Anaerobic co-digestion of sewage sludge and other organic wastes at a wastewater treatment plant (WWTP) is a promising method for both energy and material recovery. However, transportation and storage of wastes to WWTP may be the bottleneck for the successful implementation of this technology. In case of wet wastes and wastewater it is possible to reduce their volume and as a result the transportation and storage cost by using a drying process. During this study, the optimization of biogas production from sewage sludge (SS) was attempted by co-digesting with a dried mixture of food waste, cheese whey and olive mill wastewater (FCO). A series of laboratory experiments were performed in continuously-operating reactors at 37°C, fed with thermal dried mixtures of FCO at concentrations of 3%, 5% and 7%. The overall process was designed with a hydraulic retention time (HRT) of 24days. FCO addition can boost biogas yields if the mixture exceeds 3% (v/v) concentration in the feed. Any further increase of 5% FCO causes a small increase in biogas production. The reactor treating the sewage sludge produced 287ml CH 4 /L reactor /d before the addition of FCO and 815ml CH 4 /L reactor /d (5% v/v in the feed). The extra FCO-COD added (7% FCO v/v) to the feed did not have a negative effect on reactor performance, but seemed to have the same results. In all cases, the estimated biodegradability of mixtures was over 80%, while the VS removal was 22% for the maximum biomethane production (5% v/v). Moreover, co-digestion improved biogas production by 1.2-2.7 times. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Sludge reduction by lumbriculus variegatus in Ahvas wastewater treatment plant

    NARCIS (Netherlands)

    Basim, Y.; Farzadkia, M.; Jaafarzadeh, N.; Hendrickx, T.L.G.

    2012-01-01

    Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. Application of

  19. Corrosivity of cement pastes with addition of sludge generated in water treatment plant

    International Nuclear Information System (INIS)

    Rodrigues, R.A.; Martins, B.E.D.B.S.; Couto, V.M.P.; Carvalho, L.J.; Almeida, V.C.

    2011-01-01

    The amount of sludge produced in a water treatment plant (WTP) is an important economic factor in the context of waste treatment. The present article has the objective of study the corrosion of cement pastes produced with blended sludge. Aqueous extracts were produced from the milling of masses containing 5%, 10% and 30% of sludge in relation to cement after 28 days of healing. These extracts were used for polarization assays in order to determine the corrosiveness of the folders when in contact with the used fittings. Moreover, other chemical analysis tests were carried out for sludge characterization: X-ray fluorescence and X-ray diffraction. The obtained results point to the possibility of use of the studied cement masses in the development of construction materials promoting the economic reuse of WTP sludge before discarded in landfills. (author)

  20. Chemical dissolving of sludge from a high level waste tank at the Savannah River Plant

    International Nuclear Information System (INIS)

    Bradley, R.F.; Hill, A.J. Jr.

    1977-11-01

    The concept for decontamination and retirement of radioactive liquid waste tanks at the Savannah River Plant (SRP) involves hydraulic slurrying to remove most of the settled sludges followed by chemical dissolving of residual sludges. Dissolving tests were carried out with small samples of sludge from SRP Tank 16H. Over 95 percent of the sludge was dissolved by 8 wt percent oxalic acid at 85 0 C with agitation in a two-step dissolving process (50 hours per step) and an initial reagent-to-sludge volume of 20. Oxalic acid does not attack the waste tank material of construction, appears to be compatible with the existing waste farm processes and equipment after neutralization, and with future processes planned for fixation of the waste into a high-integrity solid for packaging and shipping

  1. NEW TECHNOLOGICAL MODEL USING PV TO COLLECT AND PARTIALLY DRY THE ACTIVE SLUDGE FROM NATURALS OR HYDROPOWER LAKES

    Directory of Open Access Journals (Sweden)

    RADULESCU V.

    2017-09-01

    Full Text Available The present paper is structured in six parts. In the first part are mentioned the topic importance and the new problems appeared into last decades, related to the environmental problems in natural or hydropower lakes. This new solution using renewable resources based on PV-photovoltaic panels intends to resolve these aspects. As area for testing were selected two natural reservations lakes. Based on some experimental measurements made during three months in 2015, was determined the quality of water, main parameters, presented in part two. In the third part are briefly presented the actual environmental conditions and in part four the effects on the active sludge deposits appeared due excess developed vegetation. In part five is presented the prototype model used to solve the local problem, to collect, compact and partially dry the active sludge. The extracted sludge can be in short time integrally consumed for agricultural purpose, as ecologic and nutritive fertiliser as to restore the agriculture lands. The sludge, knew in the past for its therapeutic utilisation, more then one hundred ago, nowadays due ecological and biological changes lost his efficiency. The reconstruction of the local ecologic balance and for the sludge to recover its therapeutic properties using renewable resources without disturb the environment are the main objectives of this research. Finally some conclusions and references are presented.

  2. "Recovery of Iron Coagulants From Tehran Water-Treatment-Plant Sludge for Reusing in Textile Wastewater Treatment"

    OpenAIRE

    F Vaezi; F Batebi

    2001-01-01

    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 ...

  3. Return sludge employed in enhancement of color removal in the integrally industrial wastewater treatment plant.

    Science.gov (United States)

    Liu, Shin-shou; Liang, Tsun-teng

    2004-01-01

    In this study, the recirculation of chemical sludge and integrated sludge were employed for enhancement of color removal in an integrally industrial wastewater treatment plant. The jar test was conducted for simulating chemical coagulation process with different coagulants, aluminum sulfate and polyaluminum chloride (PACl), after different activated sludge systems (with air or high-purity oxygen). The results showed that with sludge recirculation the process of coagulation for the color removal has up to 35% enhancement in comparison with no sludge recirculation. Meanwhile, the color removal enhancement of coagulant aluminum sulfate was approximately 2 to 3-times the color removal enhancement of coagulant PACl at the optimum ratio of return sludge. In coagulation process with influent color of 1220 true color unit (TCU), the optimum dosage of return sludge was 3010mg/L, when coagulant PACl or aluminum sulfate was employed. In coagulation process with influent color of 536 TCU, the optimum dosages of return sludge were 2340 and 4680mg/L using PACl and aluminum sulfate, respectively.

  4. Mineralogy and metals speciation in Mo rich mineral sludges generated at a metal recycling plant.

    Science.gov (United States)

    Vemic, M; Bordas, F; Guibaud, G; Joussein, E; Labanowski, J; Lens, P N L; van Hullebusch, E D

    2015-04-01

    In France, more than 250 million metric tons of sludges need to be treated each year. These sludges are either dumped on the landfills or reused as secondary resources in order to preserve natural resources. A large portions of these sludges are mineral sludges, originating from metal recycling plants. In order to estimate their metal recovery potential, these mineral sludges were characterized. Four types of mineral sludge samples were collected from a metal recycling plant (3 from the recycling plant storage areas (bulk storage, barrel storage and storage shed) and 1 from the collection basin). The sludges were characterized, wherein the Mo, Ni, Cr, Co, Zn and W content and speciation were quantified. The samples had pH values between 5.9 and 10.3 with organic matter contents varying between 6.3% (storage shed) and 29.5% (bulk storage) (loss on ignition at 500 °C). Based on their leaching properties, the four mineral sludge samples (in the case of Mo) and the bulk storage sludge (in the case of Ni and Zn) were classified as potentially hazardous regarding the EN 12457-1 and EN 12457-2 method. Mineralogical results reveal that both bulk storage and the storage shed give the highest contributions to the metal content of the collection basin sample. Sequential extraction of the collection basin samples indicated that Mo is bound to the oxidizable and residual fraction, while Ni, Cr and Co were bound to the residual fraction, and Zn to the soluble acid fraction, respectively. W tends to be equally distributed among all extracted fractions. A strong correlation existed between Mo and Co, as well as between Ni, Zn and Cr, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Evaluation of three analytical techniques used to determine high levels of volatile organic compounds in type IV sludge from Rocky Flats Plant

    International Nuclear Information System (INIS)

    Parish, K.J.; Applegate, D.V.; Tsai, Y.

    1996-01-01

    Before disposal, radioactive sludge (Type IV) from Rocky Flats Plant (RFP) must be evaluated for volatile organic compound (VOC) content. The Type IV sludge consists of organic solvents, degreasers, cutting oils, and transuranic (TRU) waste mixed with calcium silicate (MicroCel E reg-sign) and Oil Dri reg-sign to form a grease or paste-like material. For laboratory testing, a simulated Type IV RFP sludge (nonradioactive) was prepared at Argonne National Laboratory-East. This sludge has a composition similar to that expected from field samples. On the basis of historical information, a typical Type IV sludge is expected to contain approximately 1-10 percent of three target VOCs. The objective of this work is to evaluate three proposed methods for the determination of high levels of these three VOCs in Type IV sludge. The three methods are (1) static headspace gas analysis, (2) methanol extraction, and (3) ethylene glycol extraction. All three methods employ gas chromatography/mass spectrometry (GC/MS). They were evaluated regarding general method performance criteria, ease of operation, and amounts of secondary mixed waste generated

  6. Performance of 14 full-scale sewage treatment plants: comparison between four aerobic technologies regarding effluent quality, sludge production and energy consumption.

    Science.gov (United States)

    Vera, I; Sáez, K; Vidal, G

    2013-01-01

    The performance of 14 Full-Scale Sewage Treatment Plants (STPs) was evaluated. STPs were divided into four aerobic technologies: a) Aerated Lagoon (AL), and three configurations of activated sludge technologies, b) conventional (CAS), c) Extended Aeration (EA), d) Sequencing Batch Reactor (SBR). Comparison between these configurations were made regarding: a) control parameters, organic loading rate (OLR), Mixed Liquor Volatile Suspended Solids (MLVSS) concentrations, Food to Microorganism ratio (F/M), sludge age (theta(c)), Hydraulic Retention Time (HRT) and return sludge ratio (R); b) effluent quality, through 5-day Biological Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Total Kjeldahl Nitrogen (TKN), Total Phosphorus (TP); and c) indicators related to sludge production (on a dry basis) and electrical energy consumption. Also, complementary costs analyses were made. The results show that in terms of effluent quality, for all configurations organic matter (BOD5 and COD) and TKN removal efficiency were up to 90%, while TSS and TP were up to 90% and 50%, respectively. However, CAS, EA, SBR, and AL had stability problems with effluent concentrations. The results of the electrical energy consumption and sludge production analyses show that SBRs reduce these indicators by 40%. Cost analysis showed that CAS, EA, SBR and AL had similar cost structures, with more than 50% of total operating and maintenance cost being related to electrical energy and sludge management. Therefore, SBR could be defined as the configuration with a more stable performance.

  7. The effect of low-temperature transformation of mixtures of sewage sludge and plant materials on content, leachability and toxicity of heavy metals.

    Science.gov (United States)

    Gondek, Krzysztof; Baran, Agnieszka; Kopeć, Michał

    2014-12-01

    The aim of the study was to determine the influence of the process of low-temperature transformation and the addition of plant material to sewage sludge diversifying the content of mobile forms of heavy metals and their ecotoxicity. The experimental design included: sewage sludge+rape straw, sewage sludge+wheat straw, sewage sludge+sawdust, sewage sludge+bark and sewage sludge with no addition. The mixtures were subjected to thermal transformation in a chamber furnace, under conditions without air. The procedure consisted of two stages: the first stage (130°C for 40 min) focused on drying the material, whereas in the second stage (200°C for 30 min) proper thermal transformation of materials took place. Thermal transformation of the materials, caused an increase in total contents of heavy metals in comparison to the material before transformation. From among elements, the cadmium content changed the most in materials after thermal transformation. As a result of thermal transformation, the content of water soluble form of the heavy metals decreased significantly in all the prepared mixtures. Low toxicity of the extracts from materials for Vibrio fischeri and Lepidium sativum was found in the research, regardless of transformation process. L. sativum showed higher sensitivity to heavy metals occurring in the studied extracts from materials than V. fischeri, evidence of which are the positive significant correlations between the content of metals and the inhibition of root growth of L. sativum. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Elimination of pathogenic bacteria in sewage sludge during the solar drying; Eliminacion de bacterias patogenas en lodos residuales durante el secado solar

    Energy Technology Data Exchange (ETDEWEB)

    Cota Espericueta, Alma Delia; Ponce Corral, Carlos [Instituto de Ciencias Biomedicas, Universidad Autonoma de Ciudad Juarez, Ciudad Juarez, Chihuahua, (Mexico)

    2008-11-15

    This paper describes the performance of a solar dryer capable of bacterial pathogen removal from the physicochemical sludge of the main wastewater treatment plant for Ciudad Juarez, Mexico. The solar setup was proposed as an alternative solution, technically feasible, for reducing the volume of the 135 tons of sludge produced per day in this plant. The experimental-greenhouse prototype has a 4.5 m{sup 2} collection area, a 1 m{sup 3}-drying bed, and automatic systems for ventilation, extraction, and data acquisition. The automatic operation was controlled by temperature and humidity differences between internal and external conditions. Global solar radiation, pH and water content of the sludge were monitored. The overall effectiveness of the solar dryer was determined by assessing thermal and microbiological performance. Water content in sludge during the process was used as an indicator of thermal effectiveness. The microbiological elimination was quantified at different residence times considering two contamination indicators: faecal coliforms and Salmonella spp. Quantification of the pathogenic microorganisms was carried out by the multiple-tube fermentation technique presented in the Mexican regulation NOM-004-SEMARNAT-2002. The thermal results related to the water content showed an exponential decay that achieved up to a 99 % reduction. Regarding microbiological removal effectiveness, there was a strong dependence between the number of bacteria present and the water content in the sludge. As a consequence, with the removal of 92 % of water, it was verified that the elimination of faecal coliforms fell from 3.8x10{sup 6} to 1.6 MPN per gram of dried sludge; and for Salmonella spp. the reduction was from 1.5x10{sup 1}3 to 1.9x10{sup 3} MPN per gram of dried sludge. [Spanish] La presente investigacion describe el desempeno de un secador solar con respecto a la eliminacion de bacterias patogenas contenidas en lodos fisicoquimicos provenientes de la principal

  9. STABILIZATION OF DRY SLUDGE OF LIQUID WASTE OF LEATHER TREATMENT BY USING FLY ASH

    Directory of Open Access Journals (Sweden)

    Cahya Widiyati

    2010-06-01

    Full Text Available The experiment of solidification of dry sludge of liquid waste of leather treatment are containing chrome (Cr by using fly ash has been done.  The experiment objective are immobilize Cr in the solid waste by using pozzoland cement was made of fly ash in order to stable in the repository.  The experiment were carried out by solidification of solid waste are containing total chrome of 1480.5 mg/kg sum of 2 - 10 weight % of (water + pozzoland cement by using pozzoland cement was made from the mixture of fly ash and calcite were burned at 1000 oC temperature for 2 hours.  The characterization of the solid composite of stabilization result consist of the compressive strength test and the leaching test by American Nuclear Society (ANS-16.1 method.  The experiment result were shown that pozzoland cement  can binding solid waste sum of 10 weight % of (water + pozzoland cement became the composite of waste concrete with the compressive strength of 577 ton/m2 and the chrome leaching test for 14 days of 0.059 mg/l.  The composite of waste concrete according to Bapedal rule for solidification of toxic waste with minimum compressive strength of 10 ton/m2 and maximum leached chrome of 5 mg/L.   Keywords: stabilization, solid waste, leather treatment, fly ash.

  10. Utilization of petroleum effluent treatment plant sludge in making blended cement

    Energy Technology Data Exchange (ETDEWEB)

    Saikia, N.J.; Bordoloi, D.; Sengupta, P.; Borthakur, P.C. [Regional Research Laboratory, Jorhat (India)

    2001-07-01

    Treatment plants for effluents from oil-fields generate large quantities of sludge that contains substances with lime, alumina, silica, carbonates, and sulfates. A study was conducted to examine the pozzolanic activity of kaolin, calcined in the presence of effluent treatment plant sludge of the Lakwas oil field in Assam India. The physical properties of blended cements containing metakaolin were identified. It was determined that sludge ash consumes significant amounts of lime. Depending on the amount of sludge used in calcination of the clay, the pozzolanic activity of metakaolin was found to increase or decrease. The compressive strength of the mortar at 3, 7 and 28 days exhibited similar properties in blended cements made with metakaolin. 17 refs., 4 tabs., 1 fig.

  11. Electroosmotically enhanced sludge dewatering-pilot-plant study

    CSIR Research Space (South Africa)

    Smollen, M

    1994-01-01

    Full Text Available role in determining the ease or difficulty of phase separation. It seems that the inefficiency of dewatering applied to gelatinous and fine-particle sludges can be overcome by mechanical dewatering enhanced by electroosmosis. A prototype pilot...

  12. Verification of an alternative sludge treatment process for pathogen reduction at two wastewater treatment plants in Victoria, Australia.

    Science.gov (United States)

    Irwin, R; Surapaneni, A; Smith, D; Schmidt, J; Rigby, H; Smith, S R

    2017-08-01

    At South East Water wastewater treatment plants (WwTPs) in Victoria, Australia, biosolids are stockpiled for three years in compliance with the State guidelines to achieve the highest pathogen reduction grade (T1), suitable for unrestricted use in agriculture and landscaping. However, extended stockpiling is costly, may increase odour nuisance and greenhouse gas emissions, and reduces the fertiliser value of the biosolids. A verification programme of sampling and analysis for enteric pathogens was conducted at two WwTPs where sludge is treated by aerobic and anaerobic digestion, air drying (in drying pans or solar drying sheds) and stockpiling, to enumerate and, if present, monitor the decay of a range of enteric pathogens and parasites. The sludge treatment processes at both WwTPs achieved T1 grade biosolids with respect to prescribed pathogenic bacterial numbers (3 log 10 enteric virus reduction after a storage period of one year. No Ascaris eggs were detected in the influent to the WwTPs, confirming previous studies that the presence of helminth infections in Victoria is extremely low and that Ascaris is not applicable as a control criterion for the microbiological quality of biosolids in the region.

  13. Filterability of membrane bioreactor (MBR) sludge: impacts of polyelectrolytes and mixing with conventional activated sludge.

    Science.gov (United States)

    Yigit, Nevzat O; Civelekoglu, Gokhan; Cinar, Ozer; Kitis, Mehmet

    2010-01-01

    The main objective of this work was to investigate the filterability of MBR sludge and its mixture with conventional activated sludge (CAS). In addition, the impacts of type and dose of various polyelectrolytes, filter type and sludge properties on the filterability of both MBR and Mixed sludges were determined. Specific cake resistance (SCR) measured by the Buchner funnel filtration test apparatus and the solids content of the resulting sludge cake were used to assess the dewaterability of tested sludges. The type of filter paper used in Buchner tests affected the results of filterability for MBR, CAS and Mixed sludges. SCR values and optimum polyelectrolyte doses increased with increasing MLSS concentrations in the MBR, which suggested that increase in MLSS concentrations accompanied by increases in EPS and SMP concentrations and a shift toward smaller particles caused poorer dewaterability of the MBR sludge. The significant differences observed among the filterability of CAS and MBR sludges suggested that MLSS alone is not a good predictor of sludge dewaterability. Combining CAS and MBR sludges at different proportions generally improved their dewaterability. Combining MBR sludges having typically high MLSS and EPS concentrations with CAS having much lower MLSS concentrations may be an option for full-scale treatment plants experiencing sludge dewaterability problems. Better filterability and higher cake dry solids were achieved with cationic polyelectrolytes compared to anionic and non-ionic ones for all sludge types tested.

  14. Iodine-131 in sewage sludge from a small water pollution control plant serving a thyroid cancer treatment facility.

    Science.gov (United States)

    Rose, Paula S; Swanson, R Lawrence

    2013-08-01

    Iodine-131 (half-life = 8.04 d) is the most widely used radionuclide in medicine for therapeutic purposes. It is excreted by patients and is discharged directly to sewer systems. Despite considerable dilution in waste water and the relatively short half-life of I, it is readily measured in sewage. This work presents I concentrations in sewage sludge from three water pollution control plants (WPCPs) on Long Island, NY. Iodine-131 concentrations ranged from 0.027 ± 0.002 to 148 ± 4 Bq g dry weight. The highest concentrations were measured in the Stony Brook WPCP, a relatively small plant (average flow = 6.8 × 10 L d) serving a regional thyroid cancer treatment facility in Stony Brook, NY. Preliminary radiation dose calculations suggested further evaluation of dose to treatment plant workers in the Stony Brook WPCP based on the recommendations of the Interagency Steering Committee on Radiation Standards.

  15. Potential investigation of Reusing Ardabil Municipal Wastewater Treatment Plant Sludge Based on AHP and TOPSIS Models

    Directory of Open Access Journals (Sweden)

    Bizhan Maghsoudlou Kamali

    2013-07-01

    Full Text Available Introduction :By ever-increasing of population, shortage of water resources and the necessity of wastewater treatment, huge volumes of sludge that is a byproduct of wastewater treatment, requires to be disposed in environmentally secure ways. The target of specifying strategic preferences of reuse of sludge has been to find the correct way of disposal or beneficial use of sludge. Material and methods: In this study, to select the best alternative for reuse of wastewater sludge two systematic methods are introduced, which four alternatives for reuse of sludge (use in agriculture, use in green space, biogas, desert combat are introduced and they are compared by four main parameters including: 1- physicochemical 2-biological 3 - economic, social and cultural, and 4 - environmental pollution situation, that each contains some criteria. In this study, first each of the related parameters and criteria are compared by the expert groups of and through questionnaire. Then these weights are entered into Expert Choice software for the analyze of AHP model and paired comparisons and weightings have been done on the related parameters and criteria. Ultimately, the output of the software is entered into TOPSIS software for the analyze of TOPSIS model until the best alternative is selected. Results: sludge of Ardabil municipal wastewater treatment plant, according to standards and EPA regulations is eligible to class B, and due to the chemical in terms of heavy metals have special (excellent quality and contains considerable quantities of organic substance, nutrients and micronutrients which indicates the fertilizer value of the sludge. Conclusion: The result of this comparison has shown that the application of sludge in green spaces is the most appropriate alternative and then use in agriculture, biogas alternative, and desert combat alternative are, respectively, placed in the second to fourth preference for the reuse of sludge derived from municipal

  16. Potential impacts of using sewage sludge biochar on the growth of plant forest seedlings

    Directory of Open Access Journals (Sweden)

    Maria Isidoria Silva

    Full Text Available ABSTRACT: Sewage sludge has long been successfully used in the production of nursery plants; however, some restriction may apply due to its high pathogenic characteristics. The process of charring the organic waste significantly reduces that undesired component and may be as effective as the non-charred residue. The aim of this study was to evaluate the effect of sewage sludge biochar on the growth and morphological traits of eucalyptus ( Eucalyptus grandis L. seedlings, and compare results with those observed when using uncharred sewage sludge. Treatments were arranged in a completely randomized design, in a 2 x 2 factorial scheme, with four replications. Charred and non-charred sewage sludge were tested with and without NPK addition. A control treatment was also evaluated. Ten weeks old eucalyptus seedlings were transferred to the pots and grew for eight weeks. Chlorophyll content, plant height and stem diameter were measured at 0, 30 and 60 days after transplant. Shoot and root biomass were measured after plant harvest. Dickson Quality Index was calculated to evaluate the overall quality of seedlings. Biochar was effective in improving the seedlings quality, and had similar effects as the non-charred waste. Therefore, sewage sludge biochar has the potential to improve the process of production of forest species seedlings and further reduce the environmental risks associated with the use of non-charred sewage sludge.

  17. Co-digestion of sewage sludge from external small WWTP's in a large plant

    Science.gov (United States)

    Miodoński, Stanisław

    2017-11-01

    Improving energy efficiency of WWTPs (Waste Water Treatment Plants) is crucial action of modern wastewater treatment technology. Technological treatment process optimization is important but the main goal will not be achieved without increasing production of renewable energy from sewage sludge in anaerobic digestion process which is most often used as sludge stabilization method on large WWTP's. Usually, anaerobic digestion reactors used for sludge digestion were designed with reserve and most of them is oversized. In many cases that reserve is unused. On the other hand, smaller WWTPs have problem with management of sewage sludge due to lack of adequately developed infrastructure for sludge stabilization. Paper shows an analysis of using a technological reserve of anaerobic digestion reactors at large WWTP (1 million P.E.) for sludge stabilization collected from smaller WWTP in a co-digestion process. Over 30 small WWTPs from the same region as the large WWTP were considered in this study. Furthermore, performed analysis included also evaluation of potential sludge disintegration pre-treatment for co-digestion efficiency improvement.

  18. Plant-soil interactions of sludge-borne heavy metals and the effect ...

    African Journals Online (AJOL)

    No negative effects of heavy metal contamination in plant parts of the crops could be proven. Results showed that application of sludge to different soils could be useful in order to increase crop growth over a 28 d period in the glasshouse. Soil, plant and water quality monitoring, together with the prevention of metals ...

  19. An Operations Manual for Achieving Nitrification in an Activated Sludge Plant.

    Science.gov (United States)

    Ontario Ministry of the Environment, Toronto.

    In Ontario, the attainment of nitrification (oxidation of ammonia) in activated sludge plants is receiving increased attention. Nitrification of waste water is a necessary requirement because it reduces plant discharge of nitrogenous oxygen demand and/or toxic ammonia. However, this new requirement will result in added responsibility for…

  20. Do we know how plants sense a drying soil?

    Directory of Open Access Journals (Sweden)

    Streck Nereu Augusto

    2004-01-01

    Full Text Available The reduction of crop growth and yield in dry areas is largely due to stomatal closure in response to dry soil, which decreases photosynthesis. However, the mechanism that causes stomatal closure in a drying soil is a controversial issue. Experienced and respected plant physiologists around the world have different views about the primary sensor of soil water shortage in plants. The goal of this review is to present a chronological synthesis about the evidence of the possible candidates for the mechanism by which plants sense a drying soil. Hydraulic signals in the leaves as the mechanism that causes stomatal closure dominated the view on how plants sense a drying soil during the 70?s and the early 80?s. In the middle 80?s, studies suggested that stomatal conductance is better correlated with soil and root water status than with leaf water status. Thus, chemical signals produced in the roots dominated the view on how plants sense a drying soil during the late 80?s and early 90?s. During the second half of the 90?s, however, studies provided evidence that hydraulic signals in the leaves are still better candidates for the mechanism by which plants sense a drying soil. After more than 60 years of studies in plant-water relations, the question raised in the title still has no unanimous answer. This controversial issue is a good research rationale for the current generation of plant physiologists.

  1. Problematic issues of air protection during thermal processes related to the energetic uses of sewage sludge and other waste. Case study: Co-combustion in peaking power plant.

    Science.gov (United States)

    Hroncová, Emília; Ladomerský, Juraj; Musil, Juraj

    2018-03-01

    Currently, it is necessary to deal with issues related to the emissions as there is a constantly increasing interest in combusting sludge from sewage treatment plants in the boilers for wood. An analysis of the energetic importance of the combustion of sewage sludge has already been carried out, but the effects of various treatments of the sludge are not always clear, e.g. composting and subsequent combustion to the air pollution. Investments in other thermal processes of energetic utilisation of sewage sludge and organic waste are not always successfully implemented. The objective of this paper is to point out some problematic cases for acceptance of thermal processes related to energetic use of waste in terms of the air protection. The other aim is to mention the experience with solutions of such issues in Slovakia. There are mentioned first results of the operational validation experiments during the energy generation in circulating fluidized bed boiler in peaking power plant (Power 110MW) with the addition of the so-called alternative fuel based on wood and sewage sludge to the main fuel - black coal (anthracite). And there has already been achieved the highest share of 12.4%w. (dry matter) of sewage sludge in form of compost in blend with black coal, which is technologically viable. Moreover analyzed the problems of the authorization and operation of the co-combustion of sewage sludge and of combustion of products of various kinds of pyrolysis waste - pyrolysis gas and pyrolysis oil are analyzed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Utilization of alum sludge as chromium removal

    Science.gov (United States)

    Zahari, Nazirul Mubin; Sidek, Lariyah Mohd; Zulkifli, Muhammad Azmeer Asyraf; Hua, Chua Kok; Jalil, Nurulhidayah Abdul

    2017-09-01

    The amount of alum sludge produced at water treatment plant has become a problem where it is highly costly in order to dispose them. Various research was conducted to find the most suitable and economic alternative to recycle and reused of alum sludge. In this study, alum sludge was retrieved from Waterworks where it was dewatered, dried, grounded and sieved to obtain smallest particle sizes of alum sludge. The synthetic water was prepared at the laboratory in as it was used to imitate the properties of real water contaminated with chromium. This study was conducted to determine the percentage reduction of chromium concentration in synthetic water by using alum sludge as absorbent. The percentage reduction of chromium was observed under the effect of initial concentration of chromium and the height of alum sludge. The result indicates that chromium concentration reduction was the highest at the lowest initial concentration and at the highest height of alum sludge and vice versa.

  3. Vacuum drying plant for evaporator concentrates

    Energy Technology Data Exchange (ETDEWEB)

    Benavides, E. [ENSA, Madrid (Spain)

    2001-07-01

    Volume reduction systems applied to evaporator concentrates in PWR and BWR save a significant amount of drums. The concentration to dry product is a technique that reaches the maximum volume reduction, compared to conventional techniques (cementation, polymerisation). Four Spanish N.P.P. (3 PWR and 1 BWR) have selected ENSA's process by means of fixed ''in drum vacuum drying system''. A 130-litre steel drum is used for drying without any additional requirement except vacuum resistance. This steel drum is introduced into a standard 200-litre drum. Five centimeters concrete shielding cylinder exists between both drums. Final package is classified as 19 GO according to ENRESA's acceptance code (dry waste with 5 cm concrete between 130-l and 200-l drum). The generation of cemented waste in five N.P.P. versus dried waste will be reduced 83%. This reduction will save a considerable amount in disposal costs. (authors)

  4. Management experience on microthrix parvicella bulking in an activated sludge wastewater treatment plant

    International Nuclear Information System (INIS)

    De Bortoli, N.; Mion, M.; Di Giorgio, G.; Goi, D.

    2005-01-01

    Activated sludge wastewater treatment processes may give inefficiencies due to biological imbalances involving biomass. In fact, external causes as temperature lowering can increase the proliferation of the filamentous bacterium Microthrix parvicella into activated sludge flocks. Microthrix parvicella increases may create dangerous bulking phenomena compromising secondary settling without varying bio-kinetic parameters. In this case of study, a method to defeat growth of Microthrix parvicella has been set up. Aluminium poly-chloride (PAC) has been added to activated sludge contained into oxidation tanks of a municipal wastewater treatment plant, where a large growth of Microthrix parvicella has been periodically observed. It has been demonstrated that a definite PAC concentration can reduce Microthrix parvicella proliferation into activated sludge flocks so bulking phenomena can be well reduced [it

  5. Petroleum Sludge as gypsum replacement in cement plants: Its Impact on Cement Strength

    Science.gov (United States)

    Benlamoudi, Ali; Kadir, Aeslina Abdul; Khodja, Mohamed

    2017-08-01

    Due to high cost of cement manufacturing and the huge amount of resources exhaustion, companies are trying to incorporate alternative raw materials or by-products into cement production so as to produce alternative sustainable cement. Petroleum sludge is a dangerous waste that poses serious imparts on soil and groundwater. Given that this sludge contains a high percentage of anhydrite (CaSO4), which is the main component of gypsum (CaSO4.2H2O), it may play the same gypsum role in strength development. In this research, a total replacement of gypsum (100%) has been substituted by petroleum sludge in cement production and has led to an increase of 28.8% in UCS values after 28 curing days. Nevertheless, the burning of this waste has emitted a considerable amount of carbon monoxide (CO) gas that needs to be carefully considered prior to use petroleum sludge within cement plants.

  6. THE CONCENTRATION OF TRACE ELEMENTS IN SEWAGE SLUDGE FROM WASTEWATER TREATMENT PLANT IN GNIEWINO

    Directory of Open Access Journals (Sweden)

    Julita Karolina Milik

    2017-09-01

    Full Text Available Sewage sludge originated from wastewater treatment plants (WWTP serving rural areas are suggested for agricultural or natural usage. Before, however, sewage sludge is subjected to the several pre-treatments, which involve stabilization, hygienisation and pre-composting. These methods decrease mainly the amount of organic substances and presence of microorganisms, but hardly affects concentrations of heavy metals. The advantages of using sludges as fertilizer for improving and sustaining soil fertility and crop production are many. The addition of sewage sludge to soils could affect potential availability of heavy metals. Trace elements are distributed in the soil in various forms: solid phases, free ions in soil solution, soluble organic-mineral complexes, or adsorbed on colloidal particles. In the study the concentrations of trace elements (Pb, Cd, Cr, Hg, Ni, Zn, Al, As, Se, B, Ba, Br, Ca, Cu, Fe, Mn, Na, Ga, Li, Mo, Sr, Mg, K, Ru, Tl, V, U was tested in sewage sludge obtained from (WWTP serving rural areas (PE< 9 000. In each case, the tested sewage sludge was meeting the criteria of stabilization and was used for agriculture and land reclamation purpose. All the samples were collected in 2016 and were subjected to microwave mineralization in a closed system in aqua regia. The total amound of macro and microelements were determined with a ICP-OES. It was found that the total concentrations of trace metals in all of sewage sludge are the same than Polish regulation limit of pollutants for sludge to be used in agriculture. The trace elements (cadmium: 1,16 mg·kg-1/d.m. in polish sewage sludge, respectively, much higher than those in the other countries. As a most prevalent copper and zinc were observed (111,28 mg·kg-1/d.m. and 282,94 mg·kg-1/d.m.. The concentrations of copper in polish sewage sludge are much lower (49-130 mg·kg-1/d.m. than european sewage sludge (522-562 mg·kg-1/d.m.. The two out of tested heavy metals (beryllium, bismuth

  7. Effects Of Various Parameters On The Thickening Of Softening Plant Sludges

    DEFF Research Database (Denmark)

    Peters, Günther H.J.; Baumann, E. R.; Larson, M. A.

    1989-01-01

    Spectroscopic and thermal data for sludges from full-scale softening plants showed calcium and magnesium precipitated as calcite and an amorphous hydrated hydroxide, respectively. Magnesium ions were not incorporated into the calcium lattice to form a magnesian calcite. Scanning electron photomic......Spectroscopic and thermal data for sludges from full-scale softening plants showed calcium and magnesium precipitated as calcite and an amorphous hydrated hydroxide, respectively. Magnesium ions were not incorporated into the calcium lattice to form a magnesian calcite. Scanning electron...

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

    International Nuclear Information System (INIS)

    Farzadkia, M.; Gholami, M.; Darvishi Cheshmeh Soltani, R.; Yaghmaeian, K.; Shams Khorramabadi, G.

    2009-01-01

    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)

  9. Performance of Wastewater Treatment Plants in Gaza Strip Potential use of Wastewater and Sludge in Agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Shomar, B.H.; Mueller, G.; Yahya, A.

    2003-07-01

    Twelve elements (Ag, Al, As, Cd, Ca, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were analyzed in 120 composite samples of influent and effluent wastewater; the results revealed that domestic wastewater influent contains considerable amounts of heavy metals and the partially functional treatment plants of Gaza are able to remove 40-70% of most metals during the treatment process. Heavy metals in 31 industrial wastewater effluents are within the ranges of international standards. All industries of Gaza are light, despite that they have no treatment facilities, their effluents are being discharged to municipal sewerage system and the existing treatment plants are capable to absorb the industrial effluents with no significant impact on treatment bioprocesses. Thirty parameters were determined in 35 sludge samples; P, AOX, C, S, CaCO{sub 3}, Mg, Ca, Na, K, Li, Cu, Zn, Ni, Pb, Mn, Fe, Cr, Co, Cd, As, Hg, Ti, Se, Br, Rb, Th, Sr, Y, U, and Zr. Although there are no treatment facilities for sludge within the treatment plants, the results indicated that sludge in general is clean of heavy metals. Zinc and AOX only showed anomalous concentrations; more than 85% of sludge samples showed that averages of zinc and AOX are 2000 mg/kg and 550 mg Cl/kg, respectively, which exceed the standards of all industrial countries for sludge to be used in land application. (author)

  10. Sewage sludge fertiliser use: implications for soil and plant copper evolution in forest and agronomic soils.

    Science.gov (United States)

    Ferreiro-Domínguez, Nuria; Rigueiro-Rodríguez, Antonio; Mosquera-Losada, M Rosa

    2012-05-01

    Fertilisation with sewage sludge may lead to crop toxicity and environmental degradation. This study aims to evaluate the effects of two types of soils (forest and agronomic), two types of vegetation (unsown (coming from soil seed bank) and sown), and two types of fertilisation (sludge fertilisation and mineral fertilisation, with a no fertiliser control) in afforested and treeless swards and in sown and unsown forestlands on the total and available Cu concentration in soil, the leaching of this element and the Cu levels in plant. The experimental design was completely randomised with nine treatments and three replicates. Fertilisation with sewage sludge increased the concentration of Cu in soil and plant, but the soil values never exceeded the maximum set by Spanish regulations. Sewage sludge inputs increased both the total and Mehlich 3 Cu concentrations in agronomic soils and the Cu levels in plant developed in agronomic and forest soils, with this effect pronounced in the unsown swards of forest soils. Therefore, the use of high quality sewage sludge as fertiliser may improve the global productivity of forest, agronomic and silvopastoral systems without creating environmental hazards. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Comparison of bioindicator eukaryotes of activated sludge biocenoses on two water-treatment plants: a case study

    Directory of Open Access Journals (Sweden)

    Achmadulina Farida Y.

    2017-06-01

    Full Text Available Activated sludge biocenoses were compared on waste-water treatment plants in the city of Kazan, Russian Federation and the city of Teplice, Czech Republic. Based on Palia-Kovnatski index, Acanthamoeba in Kazan, Epistylis in Teplice, and Acanthamoeba and Centropyxis were dominant genera in both plants. The major subdominant generas identified were Arcella, Opercularia and Aspidisca. This indicates high nitrification ability, high water purification potential and matured activated sludge. Chemical composition of the waste-water was identified as the main factor determining the sludge biocenoses diversity. Higher sludge biodiversity (Shannon, Margalef, and Sorensen indexes was found in Kazan corresponding to more concentrated inflow water.

  12. Bio-oil production from dry sewage sludge by fast pyrolysis in an electrically-heated fluidized bed reactor

    Directory of Open Access Journals (Sweden)

    Renato O. Arazo

    2017-01-01

    Full Text Available The optimization of bio-oil produced from sewage sludge using fast pyrolysis in a fluidized bed reactor was investigated. Effects of temperature, sludge particle size and vapor residence time on bio-oil properties, such as yield, high heating value (HHV and moisture content were evaluated through experimental and statistical analyses. Characterization of the pyrolysis products (bio-oil and biogas was also done. Optimum conditions produced a bio-oil product with an HHV that is nearly twice as much as lignocellulosic-derived bio-oil, and with properties comparable to heavy fuel oil. Contrary to generally acidic bio-oil, the sludge-derived bio-oil has almost neutral pH which could minimize the pipeline and engine corrosions. The Fourier Transform Infrared and gas-chromatography and mass spectrometry analyses of bio-oil showed a dominant presence of gasoline-like compounds. These results demonstrate that fast pyrolysis of sewage sludge from domestic wastewater treatment plant is a favorable technology to produce biofuels for various applications.

  13. Irradiated Sewage Sludge for Production of Fennel Plants in Sandy Soil

    International Nuclear Information System (INIS)

    El-Motaium, R. A.; Abo El-Seoud, M. A.

    2004-01-01

    Irradiated sewage sludge (SS) has proved to be a useful organic fertilizer particularly for sandy soil. The objective of this study is to compare the response of fennel (Foeniculum vulgare L.) plants growing in sandy soil to different fertilizer regimes, organic vs. mineral. In a field experiment four levels (20, 40, 60, 80 t/ha) of irradiated and non-irradiated sewage sludge were incorporated into sandy soil, in addition to the control treatment (mineral fertilizer). Samples analysis included the biomass production at the vegetative and flowering stages, chlorophyll content, total and reducing sugars and heavy metals content of the shoots. The data indicate that the biomass production has dramatically increased as the sludge application rate increased in both irradiated and non-irradiated plots. However, the increase was significantly higher under all irradiated treatments than the corresponding rates of non-irradiated treatments at both the vegetative and flowering stages. Also, the biomass production at all levels of application was higher than the control, receiving mineral fertilizer. At the vegetative stage, the biomass values ranged from 3.1 g/plant for the control to 10.2 and 34.1 g/plant at 80 t/ha for non-irradiated and irradiated sewage sludge, respectively. Whereas, at the flowering stage the values ranged from 9.8 g/plant for the control to 23.9 and 65.1 g/plant at 80 t/ha for non-irradiated and irradiated sewage sludge, respectively. Total sugars, reducing sugar, non-reducing sugar, and chlorophyll content has increased as the sludge application rate increased. At 80t/ha application rate of irradiated sludge, the reducing sugars content was 29.39 mg/g DW at the vegetative stage and 37.85 mg/g DW at the flowering stage. Reducing sugars recorded lower values in the control plants, 14.54 mg/g DW at the vegetative stage and 18.78 mg/g DW at the flowering stage. Heavy metals (Zn, Fe, Pb, Cd) of the shoots was also determined. Sewage sludge was a good

  14. Effects of organic contaminants in sewage sludge on soil fertility, plants and animals

    International Nuclear Information System (INIS)

    Hall, J.E.; Sauerbeck, D.R.; L'Hermite, P.

    1992-01-01

    Sewage sludge production in Europe will continue to rise as a result of higher environmental standards, making disposal increasingly difficult in the future. A considerable part of this sludge is spread beneficially on agricultural land as an organic fertilizer, however, this outlet is very sensitive to the problems associated with the inorganic and organic contaminants which sludge inevitably contains. Much research has been devoted to the problems of contaminants in sludge and their potential effects on soil, plants, animals and man in recent years, and the European Commission's Concerted Action COST 681 has provided a valuable forum for the exchange of views and progress of research on sludge treatment and disposal. This book contains 19 papers presented to a joint meeting of Working Party 4 (Agricultural Value) and Working Party 5 (Environmental Effects) of COST 681, held at the German Federal Research Centre of Agriculture (FAL), Braunschweig on 6-8 June 1990. The meeting addressed two areas of current concern; the occurrence, behaviour and transfer of sludge-derived organic contaminants (Session 1), and the influence of inorganic and organic contaminants on soil micro-organisms and their activities (Session 2)

  15. Sludge valorization from wastewater treatment plant to its application on the ceramic industry.

    Science.gov (United States)

    Martínez-García, C; Eliche-Quesada, D; Pérez-Villarejo, L; Iglesias-Godino, F J; Corpas-Iglesias, F A

    2012-03-01

    The main aim of this study is to assess the effect of incorporating waste sludge on the properties and microstructure of clay used for bricks manufacturing. Wastewater treatment plants produce annually a great volume of sludge. Replacing clay in a ceramic body with different proportions of sludge can reduce the cost due to the utilization of waste and, at the same time, it can help to solve an environmental problem. Compositions were prepared with additions of 1%, 2.5%, 5%, 7.5%, 10% and 15% wt% waste sludge in body clay. In order to determine the technological properties, such as bulk density, linear shrinkage, water suction, water absorption and compressive strength, press-moulded bodies were fired at 950 °C for coherently bonding particles in order to enhance the strength and the other engineering properties of the compacted particles. Thermal heating destroys organic remainder and stabilizes inorganic materials and metals by incorporating oxides from the elemental constituent into a ceramic-like material. Results have shown that incorporating up to 5 wt% of sludge is beneficial for clay bricks. By contrast, the incorporation of sludge amounts over 5 wt% causes deterioration on the mechanical properties, therefore producing low-quality bricks. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Design for Wuhan Green sewage treatment plant using SBR activated sludge process

    OpenAIRE

    Tu, Guanyue

    2017-01-01

    The objective of the thesis project was to design a sewage treatment plant using Sequencing Batch Reactor(SBR) activated sludge process based on the requirements of Wuhan green sewage treatment plant. The main contents of the thesis are process comparison and selection,structure selection and plant layout arrangement. SBR process includes five phases,charging,aeration,sedimentation,discharge and standby process.SBR reactors treat the sewage from mechanical biological treatment facilities...

  17. Sludge busters

    International Nuclear Information System (INIS)

    Pichon, Max

    2010-01-01

    The biggest problem was that Woolgoolga couldn't handle its sludge load as the sludge ponds fill up. And there is nowhere to take it, so they have to take it to landfill. That is a very expensive way of dealing with it,” said McKibbin. It was also a growing problem, with Coffs Harbour Water budgeting $1.5 million to augment the sludge management system, including a third pond and centrifuge.But having observed the For Earth system at the Macksville Sewage Treatment plant in Nambucca, the council water authority instead opted for a 12-month trial of the system, which started last August. The aeration system was installed and some four litres a day of probiotics has been added to the 16kL sludge lagoons since then. Coffs Harbour Water's Adam Wilson is pleased with the results to date. The volume of sludge coming out of the ponds has plunged 47 per cent compared to the same period last year, solids concentration has dropped 61 per cent and the sludge dries in 10 days rather than 3-4 weeks.There are still the coldest winter months to go, but McKibbin said that presents no problems. “What happens is the cooler water temperatures will slow down the bacteria activity. But that's the beauty of adding probiotics bacteria, you can up the numbers and by doing that you're not held back by water temperature,” he said. After the initial set up cost of $22,000 and the $150 a week in probiotics, the sludge management operating costs have reduced by $1,416 per week, paying for the system in just 15 weeks. Operator time has been cut from 10 hours per week to two hours, but the biggest saving is more than halving the $3,000 a week bill to dispose of the dried sludge. Little wonder Coffs Harbour Water has already extended the use of probiotics and low energy aeration to three other water reclamation plants, though it stopped short of applying the technology to the Karangi Water Treatment Plant due to high concentrations of chemicals and the low biological content of its

  18. Ecophysiology of novel core phylotypes in activated sludge wastewater treatment plants with nutrient removal

    DEFF Research Database (Denmark)

    McIlroy, Simon Jon; Awata, Takanori; Nierychlo, Marta

    An in depth understanding of the ecology of activated sludge nutrient removal wastewater treatment systems requires detailed knowledge of the community composition and metabolic activities of individual members. Recent 16S rRNA gene amplicon surveys of activated sludge wastewater treatment plants...... with nutrient removal in Denmark indicate a core set of bacterial genera. These core genera are suggested to be responsible for the bulk of nutrient transformations underpinning the functions of these plants. While we know the basic in situ activities of some of these genera, there is little to no information...... limited to no information is available for their ecophysiology in activated sludge. A combination of MAR-FISH and SIP was applied to identify members of the genera Rhodoferax, Dechloromonas and Sulfuritalea, all within the class Betaproteobacteria, to be core denitrifiers in these systems. Similar...

  19. Effects of Sludge Compost on EC value of Saline Soil and Plant Height of Medicago

    Science.gov (United States)

    Sun, Chongyang; Zhao, Ke; Chen, Xing; Wang, Xiaohui

    2017-12-01

    In this study, the effects of sludge composting on the EC value of saline soil and the response to Medicago plant height were studied by planting Medicago with pots for 45 days in different proportions as sludge composting with saline soil. The results showed that the EC value of saline soil did not change obviously with the increase of fertilization ratio,which indicated that the EC value of saline soil was close to that of the original soil. The EC decreased by 31.45% at fertilization ratio of 40%. The height of Medicago reached the highest at 40% fertilization ratio, and that was close to 60% fertilization ratio, and the difference was significant with other treatments. By comprehensive analyse and compare,the optimum application rate of sludge compost was 40% under this test condition.

  20. Effects of dried wastewater-treatment sludge application on ground-water quality in South Dade County, Florida

    Science.gov (United States)

    Howie, Barbara

    1992-01-01

    Four test fields in the south Dade agricultural area were studied to determine the effects of sludge application on ground-water quality. Two fields had been cultivated for 10 years or more, and two had not been farmed for at least 10 years. The fields were representative of the area's two soil types (Rockdale and Perrine marl) and two major crop types (row crops and groves). Before the application of sludge, wells upgradient of, within, and downgradient of each field were sampled for possible sludge contaminants at the end of wet and dry seasons. Municipal wastewater treatment sludge from the Dade County Water and Sewe Authority Department was then applied to the fields at varying application rates. The wells at each field were sampled over a 2-year period under different hydrologic conditions for possible sludge-related constituents (specific conductance, pH, alkalinity, nitrogen, phosphorus, total organic carbon, copper, iron, magnesium, manganese, potassium, zinc, arsenic, cadmium, chloride, chromium, lead, mercury, nickel, and sodium). Comparisons were made between water quality in the vicinity of the test fields and Florida Department of Environmental Regulation primary and secondary drinking-water regulations, an between water quality upgradient of, beneath, and downgradient of the fields. Comparisons between presludge and postsludge water quality did not indicate any improvement because of retention of agrichemicals by the sludge nor did they indicate any deterioration because of leaching from the sludge. Comparisons of water quality upgradient of the fields to water quality beneath and downgradient of the fields also did not indicate any changes related to sludge. Florida Department of Environmental Regulation primary and secondary drinking-water regulations wer exceeded at the Rockdale maximum-application field by mercury (9.5 ug/L (micrograms per liter)), and the Perrine marl maximum-application field by manganese (60 ug/L) and lead (85 ug/L), and at the

  1. Monitoring and troubleshooting of non-filamentous settling and dewatering problems in an industrial activated sludge treatment plant

    DEFF Research Database (Denmark)

    Kjellerup, B. V.; Keiding, Kristian; Nielsen, Per Halkjær

    2001-01-01

    A large industrial activated sludge wastewater treatment plant had temporary problems with settling and dewatering of the sludge. Microscopical investigations revealed that the poor settling properties were not due to presence of filamentous bacteria, but poor floc properties. In order to charact......A large industrial activated sludge wastewater treatment plant had temporary problems with settling and dewatering of the sludge. Microscopical investigations revealed that the poor settling properties were not due to presence of filamentous bacteria, but poor floc properties. In order...... dewaterability. The monitoring program revealed that a deterioration of the floc strength and the settling properties in the process tanks was closely connected to downstream dewatering problems and poor effluent quality. Particularly severe problems were observed a few weeks after the production at the factory...... at this industrial plant. The described strategy can be useful in general to find and solve many solid/liquid separation problems in activated sludge wastewater treatment plants....

  2. Development of bricks with incorporation of coal ash and sludge from water treatment plant

    International Nuclear Information System (INIS)

    Silva, Mauro Valerio da

    2011-01-01

    Sludge from treatment water Brazilian plant station are, frequently, disposed and launched directly in the water bodies, causing a negative impact in the environment. Also, coal ashes is produced by burning of coal in coal-fired power stations and is the industrial solid waste most generated in southern Brazil: approximately 4 million tons/y. The efficient disposal of coal ashes is an issue due to its massive volume and harmful risks to the environment. The aim of this work was study the feasibility of incorporating these two industrial wastes in a mass used in the manufacture of ecological bricks. Samples of fly ashes from a cyclone filter from a coal-fired power plant located at Figueira County in Parana State, Brazil and waterworks sludge of Terra Preta County in Sao Paulo State, Brazil, were used in the study. Fly ash-sludge and fly ash-sludge-soil-cement bricks were molded and tested, according to the Brazilians Standards. The materials were characterized by physical-chemical analysis, X-ray diffraction, thermal analysis, morphological analysis, Fourier transform infrared spectroscopy and granulometric analysis. The results indicate that the waterworks sludge and coal ashes have potential to be used on manufacturing soil-cement pressed bricks according to the of Brazilians Standards NBR 10836/94. (author)

  3. Absorção de metais pesados do lodo de esgoto pelo feijoeiro (Phaseolus vulgaris L. Heavy Metal Uptake Of The Sewage Sludge By Bean Plants(Phaseolus vulgaris L.

    Directory of Open Access Journals (Sweden)

    Mário Miyazawa

    1998-06-01

    Full Text Available Toxicity and uptake of heavy metals of sewage sludge by beans (Phaseolus vulgaris L. were evaluated in green house experiments. Treatments consisted of 1,0 ; 2,0 and 5,0% (m/m of dry sewage sludge, collected from Londrina (Bom Retiro and ETE-Sul and Curitiba (ETE-Belém and RALF. Bean ( variety IAPAR 57 was sown three times at 0, 120 and 240 days after the treatments have been applied. Contents of Cd, Cr, Co, Cu, Ni, and Pb in bean tissues cultivated with 5,0% (m/m of all sewage sludge were similar to the control and Ba contents were reduced by increasing the quantity of sewage sludge in the soil. The Zn content in tissue bean incresed from 86 mg kg-1 of control to 462 mg kg-1 by applying 5% (m/m of sewage sludge in soil, but plant beans did not show toxicity symptons. The addition of 5% (m/m of sewage sludge increased Mn content in plants, from 193 mg kg-1 of control to 1.960 mg kg-1, showing toxity in bean leaves when the contents were more than 500 mg kg-1. The addition of sewage sludges in soils increased only available Zn carbonate and Cu organic species.

  4. Composting plant of vegetables wastes and sewage sludges in Castesdefells. Plant de compostaje de restos de poda y lodos de depuradora en Castelldefells

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    Castelldefells Municipality (Catalonia, Spain) has set up a recycling plant for vegetable wastes mixed with sewage sludge to obtain compost. The plant treats 48.000 m''3/y. of vegetable wastes, and receive 8.000 m''3/y. of sewage sludge. (Author)

  5. The effect of electron acceptors on biogas production from tannery sludge of a Mexican wastewater plant

    Science.gov (United States)

    Effluents from the leather processing plants generally are discharged into rivers or are used to irrigate farmland. The biogas production from the digestion of sludge produced could be used as alternative sources for energy and power generation. A study was carried out to examine the effects of vari...

  6. Mass and energy balances of sludge processing in reference and upgraded wastewater treatment plants.

    Science.gov (United States)

    Mininni, G; Laera, G; Bertanza, G; Canato, M; Sbrilli, A

    2015-05-01

    This paper describes the preliminary assessment of a platform of innovative upgrading solutions aimed at improving sludge management and resource recovery in wastewater treatment plants. The effectiveness of the upgrading solutions and the impacts of their integration in model reference plants have been evaluated by means of mass and energy balances on the whole treatment plant. Attention has been also paid to the fate of nitrogen and phosphorus in sludge processing and to their recycle back to the water line. Most of the upgrading options resulted in reduced production of dewatered sludge, which decreased from 45 to 56 g SS/(PE × day) in reference plants to 14-49 g SS/(PE × day) in the upgraded ones, with reduction up to 79% when wet oxidation was applied to the whole sludge production. The innovative upgrades generally entail an increased demand of electric energy from the grid, but energy recovery from biogas allowed to minimize the net energy consumption below 10 kWh/(PE × year) in the two most efficient solutions. In all other cases the net energy consumption was in the range of -11% and +28% of the reference scenarios.

  7. Detection of radionuclides originating from a nuclear power plant in sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Puhakainen, M.; Suomela, M

    1999-11-01

    Sewage sludge is a sensitive indicator of radionuclides entering the environment. Radionuclides originating in nuclear power stations have been detected in sludge found at wastewater treatment plants in communities near the power plants (NPP). The main contributor is the radionuclide discharges of the NPPs into the atmosphere, but workers may transmit small amounts through their clothes or skin, or from internal contamination. The purpose of the present investigation was to determine the amounts of radionuclides in sewage sludge and to obtain information on transport of the radionuclides from the NPPs to the wastewater treatment plants. Under normal operating conditions and during annual maintenance and refuelling outages at the Loviisa and Olkiluoto NPPs, sewage sludge samples were taken at wastewater treatment plants in communities located in the vicinity of the plants. With the exception of {sup 131}I, the most significant activities in discharges into the air from the Loviisa NPP were due to {sup 110}mAg. The latter was also noted most frequently in the sewage sludge at the wastewater treatment plant in the town of Loviisa about 10 km from the Loviisa pressurised water reactor (PWR) NPP. The other nuclides probably originating from the Loviisa NPP were {sup 51}Cr, {sup 54}Mn, {sup 58}Co, {sup 59}Fe, {sup 60}Co, {sup 110}mAg and {sup 124}Sb. In the wastewater treatment plant in the town of Rauma, about 10 km from the Olkiluoto boiling water reactor (BWR) NPP, the only nuclides possibly origination from the NPP were {sup 54}Mn, {sup 58}Co and {sup 60}Co. In the wastewater treatment plant, the variation in concentration of {sup 60}Co in sludge did not correlate with the activities measured in precipitation. The occurrence of the nuclide in the treatment plant did not correlate over time with the amounts of discharge from the NPP. This suggests that at least some of the activity was transported to the wastewater treatment plant via routes other than precipitation

  8. Combustion of sewage sludge water in Netherland; Incineracion de lodos procedentes de aguas residuales en Holanda

    Energy Technology Data Exchange (ETDEWEB)

    Viles, A. W. van der

    1995-12-31

    The Dutch policy for sewage sludge disposal has been changed in the last decades. Instead of predominantly beneficial use thermal processes, such as sludge drying and incineration, will become increasely more necessary. These processes are subject to very strict environmental regulations. Sludge incineration has to meet the very strict flue gas emission requirements of the Dutch Guideline on Incineration. The consequences for a new sludge incineration plant are reviewed.

  9. Removal of secondary sludge from steam generators used in French 900 class nuclear power plants

    International Nuclear Information System (INIS)

    Lebouc, B.

    1982-09-01

    The objective is to remove magnetite deposits which have formed on a steam generator tubesheet during plant operation. The deposits are separated from the tubesheet by spraying water at high pressure (about 200 bar at lance nozzle outlets) on each tube bundle ligament, i.e. the spaces between steam generator tubes. The water is recovered in suction lines and then filtered in two seperate units. The residue obtained after settling is removed in the form of solid waste. This paper presents the sludge lancing technique (spray lances, sludge recovery, liquid waste, cooling). A typical operating sequence is detailed (duration, personnel). Specifications for the equipment used are given

  10. Establishment of optimum plant densities for dry season sorghum ...

    African Journals Online (AJOL)

    (Received 21 April, 1998; accepted 2 December, 2001) Abstract Dry season transplanted sorghum is grown on Vertisols in the Lake Chad Basin at approximately 10,000 plants ha-1. Increasing plant density was hypothesised to be one way of increasing yields in this cropping system. To test this hypothesis, a trial was ...

  11. Conversion of sewage treatment plants on sludge digestion. Energetic and economic optimization potential

    International Nuclear Information System (INIS)

    Schmitt, Theo G.; Gretzschel, Oliver

    2014-03-01

    Investigations within the framework of the state-commissioned project ''Re-evaluation of wastewater purification plants with anaerobic sludge treatment with due consideration to framework conditions in terms of the energy and the wastewater management situation in Rhineland-Palatinate'', abbreviated ''NAwaS'', have shown that due to the rise in energy prices and availability of innovative techniques and methods it can be economically efficient, from a plant capacity of 10,000 inhabitants upwards, to convert sewage treatment plants to sludge digestion. Findings from the NAwaS project show the state of Rhineland-Palatinate to have a large potential for the conversion of sewage treatment plants to sludge digestion. Depending on the rate of price increase as well as interest rates the use of digester gas could permit an increase in electricity output by up to 50% over today's levels. Moreover, converted plants would be able to almost completely cover their own heat demand and in addition permit energy savings totalling an expected 5 kWh/(inhabitant x a). If one incorporates the possibilities offered by the procurement of sludge or suitable co-substrates from outside sources, by retrofitting sewage plants with combined heat and power stations or micro gas turbines as well as by process optimisation in existing digestion plants, this gives a further significant increase in potential production capacity and hence economic efficiency. In some of the sewage plants the above measures for saving energy and boosting energy production will even lead to energy self-sufficiency. [de

  12. Chromium fractionation and plant availability in tannery-sludge amended soil

    Science.gov (United States)

    Allué, Josep; Moya Garcés, Alba; Bech, Jaume; Barceló, Juan; Poschenrieder, Charlotte

    2013-04-01

    The leather industry represents an important economic sector in both developed and developing countries. Chromium tanning is the major process used to obtain high quality leather. Within the REACH regulation the use of Cr, especially CrVI, in the tanning process is under discussion in Europe. High Cr concentration in shoes and other Cr-tanned leather products can cause contact dermatitis in sensitive population. Moreover, the high Cr concentration is the major limiting factor for the use of tannery sludge as a source of organic matter in agricultural soils. Interest in Cr, however is not limited to its potential toxic effects. Chromium III is used as a dietary supplement because there are reports, but also controversy, about the positive effects of Cr III in glucose tolerance and type-2 diabetes. Adequate intake levels for Cr by the diet have been established between 25 and 35 µg/day for adult females and males, respectively. Sufficient supply of Cr III by the diet is preferable to the use of CrIII-salt based dietary supplements. The objective of the present work was to investigate whether Cr from tannery sludge-amended soil is available to Trigonella foenum-graecum plants, a plant used both as a spice and as a medicinal herb, because of its hypoglucemic effects. For this purpose clay loam soil (pH 7.8) was sieved (2mm) and thoroughly mixed with tannery sludge from a depuration station (Igualadina Depuració i Recuperació S.L., Igualada, Barcelona, Spain). The sludge had a Cr concentration of 6,034mg kg-1 and a 0.73 % of NH4-nitrogen. All the Cr was in the form of CrIII. Three treatments were disposed. Control soil receiving no sludge, a 60 mg kg-1 Cr treatment (10 g fresh sludge kg-1 soil) and a 120 mg kg-1 Cr treatment (20 g fresh sludge kg-1 soil). Control soil and the soil treated with 10g kg-1 sludge received NPK fertilizer in the form of ammonium sulfate, superfosfate, and KCl to rise the N,P, and K concentrations to similar levels to those achieved in the

  13. The agricultural use of water treatment plant sludge: pathogens and antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Ignacio Nadal Rocamora

    2015-12-01

    Full Text Available The use of water treatment plant sludge to restore degraded soils is customary agricultural practice, but it could be dangerous from the point of view of both health and the environment. A transient increase of either pathogenic or indicator microbial populations, whose persistence in time is variable and attributed to the characteristics of the soil (types of materials in the soil, any amendments (origin and treatments it has undergone or the weather (humidity and temperature mainly, has often been detected in soils treated with this kind of waste. Given their origin, water treatment plant sludges could lead to the transmission of a pathogens and b antibiotic-resistant microorganisms to human beings through the food chain and cause the spreading of antibiotic resistances as a result of their increase and persistence in the soil for variable periods of time. However, Spanish legislation regulating the use of sludges in the farming industry is based on a very restricted microbiological criterion. Thus, we believe better parameters should be established to appropriately inform of the state of health of soils treated with water treatment plant sludge, including aspects which are not presently assessed such as antibiotic resistance.

  14. Research on vitrification technology to immobilize radioactive sludge generated from Fukushima Daiichi power plant. Enhanced glass medium

    International Nuclear Information System (INIS)

    Amamoto, Ippei; Kobayashi, Hidekazu; Kitamura, Naoto; Takebe, Hiromichi; Mitamura, Naoki; Tsuzuki, Tatsuya; Fukayama, Daigen; Nagano, Yuichi; Jantzen, Tatjana; Hack, Klaus

    2016-01-01

    The search for an enhanced glass medium to immobilize the sludge at the Fukushima Daiichi Nuclear Power Plant is our main purpose. The iron phosphate glass (IPG) is a potential candidate as we set about assessing it by means of theoretical and experimental investigation. Based on the results of this study, the IPG showed favorable characteristics as a vitrification medium for the sludge. (author)

  15. A pilot-scale microwave technology for sludge sanitization and drying

    NARCIS (Netherlands)

    Mawioo, P.M.; Garcia, Hector A.; Hooijmans, Christine M.; Velkushanova, Konstantina; Simonič, Marjana; Mijatović, Ivan; Brdanovic, Damir

    2017-01-01

    Large volumes of sludge are produced from onsite sanitation systems in densely populated areas (e.g. slums and emergency settlements) and wastewater treatment facilities that contain high amounts of pathogens. There is a need for technological options which can effectively treat the rapidly

  16. Two Cases of Tsunami Dust Pneumonia: Organizing Pneumonia Caused by the Inhalation of Dried Tsunami Sludge after the 2011 Great East Japan Earthquake

    Science.gov (United States)

    Yamanda, Shinsuke; Kobayashi, Seiichi; Hanagama, Masakazu; Sato, Hikari; Suzuki, Satoshi; Ueda, Shinsaku; Takahashi, Toru; Yanai, Masaru

    2016-01-01

    We report two cases of organizing pneumonia (OP) secondary to the inhalation of the dried tsunami sludge which formed during the 2011 Great East Japan Earthquake and the consequent tsunami. After the disaster, both of these patients had been engaged in the restoration work. About half a month later, they developed shortness of breath and pulmonary infiltrates. These patients were diagnosed with interstitial pneumonia. Their biopsy specimens revealed multifocal peribronchiolitis and OP. An electron probe microanalysis of these specimens demonstrated the presence of elements from the earth's crust in the inflammatory lesions. These two cases indicate that exposure to dried tsunami sludge can cause OP. PMID:27980267

  17. Leachate Treatment from Sarimukti Landfill Using Ozone with Sludge from Water Treatment Plant as a Catalyst

    Directory of Open Access Journals (Sweden)

    Yudha Ramdhani Muhammad

    2018-01-01

    Full Text Available Leachate is the liquid waste from anaerobic decomposition in a landfill. The ozonation process can be used for leachate treatment. Sludge from sedimentation in water treatment plant contains 5.96% of Al and 9.35% of Si which can affect of its cation exchange capacity and affects the active site in the catalyst. This study aims to determine the effectivity of sludge in the ozonation process to treat leachate. A 1,5 L semi-batch reactor containing 1 L sample was used in this experiment with the rate of oxygen supply was at 4 L/min taken from ambient air. Two groups of sludge weighing 1.5 grams, 3.0 grams and 4.5 grams were used and activate with physically and chemically activated. The best result was obtained by the physically activated sludge with mass of 4.5 gram O3-L-4,5 AF. The differences of removal efficiency between O3-L-4,5 AF with the control (O3 for turbidity were respectively 13.02% and 7.81%, for EC were 10.57% and 8.29%, for COD were 49.44% and 37.50%, and for residual ozone concentration at the end of contact time were 7.6 mg/L and 9.7 mg/L. It can be concluded that activaed sludge and ozonation can be used as a catalyst in leachate treatment.

  18. Occurrence of bisphenol A in wastewater and wastewater sludge of CUQ treatment plant

    Directory of Open Access Journals (Sweden)

    Dipti Prakash Mohapatra

    2011-09-01

    Full Text Available The identification and quantification of bisphenol A (BPA in wastewater (WW and wastewater sludge (WWS is of major interest to assess the endocrine activity of treated effluent discharged into the environment. BPA is manufactured in high quantities fro its use in adhesives, powder paints, thermal paper and paper coatings among others. Due to the daily use of these products, high concentration of BPA was observed in WW and WWS. BPA was measured in samples from Urban Community of Quebec wastewater treatment plant located in Quebec (Canada using LC-MS/MS method. The results showed that BPA was present in significant quantities (0.07 μg L–1 to 1.68 μg L–1 in wastewater and 0.104 μg g–1 to 0.312 μg g–1 in wastewater sludge in the wastewater treatment plant (WWTP. The treatment plant is efficient (76 % in removal of pollutant from process stream, however, environmentally significant concentrations of 0.41 μg L–1 were still present in the treated effluent. Rheological study established the partitioning of BPA within the treatment plant. This serves as the base to judge the portion of the process stream requiring more treatment for degradation of BPA and also in selection of different treatment methods. Higher BPA concentration was observed in primary and secondary sludge solids (0.36 and 0.24 μg g–1, respectively as compared to their liquid counterpart (0.27 and 0.15 μg L–1, respectively separated by centrifugation. Thus, BPA was present in significant concentrations in the WWTP and mostly partitioned in the solid fraction of sludge (Partition coefficient (Kd for primary, secondary and mixed sludge was 0.013, 0.015 and 0.012, respectively.

  19. Sewage sludge as a biomass energy source

    Directory of Open Access Journals (Sweden)

    Pavel Kolat

    2013-01-01

    Full Text Available The major part of the dry matter content of sewage sludge consists of nontoxic organic compounds, in general a combination of primary sludge and secondary microbiological sludge. The sludge also contains a substantive amount of inorganic material and a small amount of toxic components. There are many sludge-management options in which production of energy is one of the key treatment steps. The most important options are anaerobic digestion, co-digestion, incineration in combination with energy recovery and co-incineration in coal-fired power plants. The goal of our applied research is to verify, if the sludge from waste water treatment plants may be used as a biomass energy source in respect of the EU legislation, which would comply with emission limits or the proposal of energy process optimizing the preparation of coal/sludge mixture for combustion in the existing fluid bed boilers in the Czech Republic. The paper discusses the questions of thermal usage of mechanically drained stabilized sewage sludge from the waste water treatment plants in the boiler with circulated fluid layer. The paper describes methods of thermal analysis of coal, sewage sludge and its mixtures, mud transport to the circulating fluidised bed boiler, effects on efficiency, operational reliability of the combustion equipment, emissions and solid combustion residues.

  20. Pilot-scale anaerobic co-digestion of sewage sludge with agro-industrial by-products for increased biogas production of existing digesters at wastewater treatment plants.

    Science.gov (United States)

    Maragkaki, A E; Fountoulakis, M; Gypakis, A; Kyriakou, A; Lasaridi, K; Manios, T

    2017-01-01

    Due to low degradability of dry solids, most of the digesters at wastewater treatment plants (WWTP) operate at low loading rates resulting in poor biogas yields. In this study, co-digestion of sewage sludge (SS) with olive mill wastewater (OMW), cheese whey (CW) and crude glycerol (CG) was studied in an attempt to improve biogas production of existing digesters at WWTPs. The effect of agro-industrial by-products in biogas production was investigated using a 220L pilot-scale (180L working volume) digester under mesophilic conditions (35°C) with a total feeding volume of 7.5L daily and a 24-day hydraulic retention time. The initial feed was sewage sludge and the bioreactor was operated using this feed for 40days. Each agro-industrial by-product was then added to the feed so that the reactor was fed continuously with 95% sewage sludge and 5% (v/v) of each examined agro-industrial by-product. The experiments showed that a 5% (v/v) addition of OMW, CG or CW to sewage sludge significantly increased biogas production by nearly 220%, 350% and 86% as values of 34.8±3.2L/d, 185.7±15.3L/d and 45.9±3.6L/d respectively, compared to that with sewage sludge alone (375ml daily, 5% v/v in the feed). The average removal of dissolved chemical oxygen demand (d-COD) ranged between 72 and 99% for organic loading rates between 0.9 and 1.5kgVSm -3 d -1 . Reduction in the volatile solids ranged between 25 and 40%. This work suggests that methane can be produced very efficiently by adding a small concentration (5%) of agro-industrial by-products and especially CG in the inlet of digesters treating sewage sludge. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Effect of oil refinery sludges on the growth and antioxidant system of alfalfa plants.

    Science.gov (United States)

    Martí, M Carmen; Camejo, Daymi; Fernández-García, Nieves; Rellán-Alvarez, Rubén; Marques, Silvia; Sevilla, Francisca; Jiménez, Ana

    2009-11-15

    The refining process in the petrochemical industry generates oil refinery sludges, a potentially contaminating waste product, with a high content of hydrocarbons and heavy metals. Faster degradation of hydrocarbons has been reported in vegetated soils than in non-vegetated soils, but the impact of these contaminants on the plants physiology and on their antioxidant system is not well known. In this study, the effect of the addition of petroleum sludge to soil on the physiological parameters, nutrient contents, and oxidative and antioxidant status in alfalfa was investigated. An inhibition of alfalfa growth and an induction of oxidative stress, as indicated by an increase in protein oxidation, were found. Also, the superoxide dismutase isoenzymes, peroxidase, and those enzymes involved in the ascorbate-glutathione cycle showed significant activity increases, parallel to an enhancement of total homoglutathione, allowing plants being tolerant to this situation. This information is necessary to establish successful and sustainable plant-based remediation strategies.

  2. Energy self-sufficient sewage wastewater treatment plants: is optimized anaerobic sludge digestion the key?

    Science.gov (United States)

    Jenicek, P; Kutil, J; Benes, O; Todt, V; Zabranska, J; Dohanyos, M

    2013-01-01

    The anaerobic digestion of primary and waste activated sludge generates biogas that can be converted into energy to power the operation of a sewage wastewater treatment plant (WWTP). But can the biogas generated by anaerobic sludge digestion ever completely satisfy the electricity requirements of a WWTP with 'standard' energy consumption (i.e. industrial pollution not treated, no external organic substrate added)? With this question in mind, we optimized biogas production at Prague's Central Wastewater Treatment Plant in the following ways: enhanced primary sludge separation; thickened waste activated sludge; implemented a lysate centrifuge; increased operational temperature; improved digester mixing. With these optimizations, biogas production increased significantly to 12.5 m(3) per population equivalent per year. In turn, this led to an equally significant increase in specific energy production from approximately 15 to 23.5 kWh per population equivalent per year. We compared these full-scale results with those obtained from WWTPs that are already energy self-sufficient, but have exceptionally low energy consumption. Both our results and our analysis suggest that, with the correct optimization of anaerobic digestion technology, even WWTPs with 'standard' energy consumption can either attain or come close to attaining energy self-sufficiency.

  3. Presence of radionuclides in sludge from conventional drinking water treatment plants. A review.

    Science.gov (United States)

    Fonollosa, E; Nieto, A; Peñalver, A; Aguilar, C; Borrull, F

    2015-03-01

    The analysis of sludge samples generated during water treatment processes show that different radioisotopes of uranium, thorium and radium, among others can accumulate in that kind of samples, even the good removal rates obtained in the aqueous phase (by comparison of influent and effluent water concentrations). Inconsequence, drinking water treatment plants are included in the group of Naturally Occurring Radioactive Material (NORM) industries. The accumulation of radionuclides can be a serious problem especially when this sludge is going to be reused, so more exhaustive information is required to prevent the possible radiological impact of these samples in the environment and also on the people. The main aim of this review is to outline the current situation regarding the different studies reported in the literature up to date focused on the analysis of the radiological content of these sludge samples from drinking water treatment plants. In this sense, special attention is given to the recent approaches for their determination. Another important aim is to discuss about the final disposal of these samples and in this regard, sludge reuse (including for example direct agricultural application or also as building materials) are together with landfilling the main reported strategies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Net positive energy wastewater treatment plant via thermal pre-treatment of sludge: A theoretical case study.

    Science.gov (United States)

    Farno, Ehsan; Baudez, Jean Christophe; Parthasarathy, Rajarathinam; Eshtiaghi, Nicky

    2017-04-16

    In a wastewater treatment process, energy is mainly used in sludge handling and heating, while energy is recovered by biogas production in anaerobic digestion process. Thermal pre-treatment of sludge can change the energy balance in a wastewater treatment process since it reduces the viscosity and yield stress of sludge and increases the biogas production. In this study, a calculation based on a hypothetical wastewater treatment plant is provided to show the possibility of creating a net positive energy wastewater treatment plant as a result of implementing thermal pre-treatment process before the anaerobic digester. The calculations showed a great energy saving in pumping and mixing of the sludge by thermal pre-treatment of sludge before anaerobic digestion process.

  5. Experience with Stabilization of SGHWR Sludge in a Commercial Plant in the United Kingdom

    International Nuclear Information System (INIS)

    Hagan, M.; Cornell, R.M.; Riley, B.; Ware, B.

    2009-01-01

    In July 2000, following a competitive tender, Nuvia Limited was contracted to design, build and commission a waste treatment plant to stabilise the active sludge stored in the External Active Sludge Tanks (EAST) at Winfrith, UK. The sludge was generated during the operational lifetime of the Steam Generating Heavy Water Reactor (SGHWR), which was in the early stages of decommissioning. This was in support of UKAEA's mission, which is to carry out environmental restoration of its nuclear sites and to put them to alternative uses wherever possible. Latterly, a new body, the Nuclear Decommissioning Authority (NDA), has become responsible for managing the UK decommissioning legacy and since 2004 UKAEA has been contracted to the NDA to deliver decommissioning work at Winfrith and other UK sites. The purpose of this commercial plant is to stabilise the radioactive sludge by encapsulation into a cement matrix within a purpose-designed 500 litre steel drum. The drum design incorporates a lost paddle mixer used to maintain homogeneity of the sludge as well as mixing it with the stabilising powders. The sludge in the EAST tanks is prepared for recovery by a process of homogenisation using in-tank stirrers. The means of reaching a narrow ratio of suspended solids within an aqueous medium will be described together with some of the problems encountered and the practical solutions devised. The material is transferred to the purpose-built Winfrith EAST Treatment Plant (WETP), where it is held in stainless steel tanks in a process area prior to being metered into a 500 litre stainless steel drum in the cell line for stabilization with powders. The cell line consists of five cells separated by shield doors designed to maintain strict contamination control. The line has a wet cell where the drums are filled with the sludge and powder, a cell with stations for curing and grouting the drums, a cell for lidding, bolting and QA inspection, a maintenance and gamma monitoring cell and a

  6. Residue characteristics of sludge from a chemical industrial plant by microwave heating pyrolysis.

    Science.gov (United States)

    Lin, Kuo-Hsiung; Lai, Nina; Zeng, Jun-Yan; Chiang, Hung-Lung

    2018-03-01

    Sludge from biological wastewater treatment procedures was treated using microwave heating pyrolysis to reduce the environmental impact of a chemical plant. In this study, major elements, trace elements, PAHs and nitro-PAHs in raw sludge, and pyrolysis residues were investigated. The contents of major element from raw sludge were carbon 46.7 ± 5.9%, hydrogen 5.80 ± 0.58%, nitrogen 6.81 ± 0.59%, and sulfur 1.34 ± 0.27%. Trace elemental concentrations including Zn, Mn, Cr, Cd, As, and Sn were 0.410 ± 0.050, 0.338 ± 0.008, 0.063 ± 0.006, 0.019 ± 0.001, 0.004 ± 0.001, and 0.003 ± 0.002 mg/g, respectively. For various pyrolysis temperatures, Ca, Fe, Sr, Cr, and Sn contents remained at almost the same level as those in raw sludge. Results indicated that these elements did not easily volatilize. The content of 16 PAH species was about 4.78 μg/g in the raw sludge and 23-65 μg/g for pyrolysis residues associated with various temperatures. The content of ten nitro-PAHs was about 58 ng/g for the raw sludge and 141-744 ng/g for pyrolysis residues. The total nitro-PAH content was highest at 600 °C and then decreased when the temperature was over 600 °C. Total nitro-PAH content was about 247 ng/g at 800 °C.

  7. Study on The Use of Sludge From Yogyakarta Waste Water Processing Plant as Environmental Friendly Organic Fertilizer

    International Nuclear Information System (INIS)

    M-Yazid; Mintargo-K; M-E-Supriyatni; Budiono

    2005-01-01

    Study on feasibility of the use of sludge from Yogjakarta Waste Water Processing Plant (JWWPP) as organic fertilizer with several aspects to be considered, such as plant nutrient content, heavy metal content and its pathogenic microbial. From the observation result is expected can be used as an input data for analyzing the use of sludge impact as fertilizer. Sludge sample was taken from JWWPP that located at Bantul. Sludge sample was dried at the room temperature, ground and weighed to be appropriate to the analysis type. The macro element content was analyzed using Neutron Activation Analysis (NAA), then counted using Ge(Li) Gamma Spectrometer. The heavy metal content, such as Pb, Cd and Hg was analyzed using AAS, while for Sm, Th, Sb, Cr and Co contents were analyzed using NAA. Sample was irradiated in order to kill pathogenic microbial, using varied doses which are 5, 10, 15, 20 and 25 kGy. Microbial observation was carried out at Microbiological Laboratory of Biological Faculty-Gadjah Mada University that include of total bacteria, Escherichia coli, Streptococcus and Salmonella. The average macro element content was determined from the analysis result, N is 4.10 ± 0.007 ppm, P is 640.51 ± 14.34, K is 3.04 ± 0.06 ppm, while micro element content consist of Mg is 79.31 ± 6.48 ppm, Zn is 599.8 ± 42.2 ppm, Cu is 16.13 ± 0.4 ppm, Ca is 117.6 ± 9.20 ppm and Fe is 4.35 ± 0.18 ppm. The range of heavy metal content consist of Pb is 73.27 - 125.65 ppm, Cd is 1.44 - 2.59 ppm, while Hg is undetected. Another that Sm is 0.04 - 18.68 ppm, Th is 2.20 - 6.37 ppm; Sb is 1.06 - 76.37 ppm, Cr is 1.94 - 51.40 ppm and Co is 0.57 - 84.03 ppm. The greatest bacteria population is Salmonella sp, then Streptococcus and the latest is Escherichia coli. The analysis result can be deduced that sludge from JWWPP can be used as organic fertilizer with specific treatment to decrease Cu, Fe and Zn content to be less then the critical value to hinder the growth of a plant. While the

  8. Development of biological process with pure bacterial cultures for effective bioconversion of sewage treatment plant sludge.

    Science.gov (United States)

    Alam, Zahangir; Muyibi, Suleyman A; Jamal, Parveen

    2007-02-15

    Forty-six bacterial strains were isolated from nine different sources in four treatment plants namely Indah Water Konsortium (IWK) sewage treatment plant (STP), International Islamic University Malaysia (IIUM) wastewater treatment plant-1,-2 and -3 to evaluate the bioconversion process in terms of efficient biodegradation and bioseparation. The bacterial strains isolated were found to be 52.2% (24 isolates) and 47.8% (22 isolates) in the IWK and IIUM treatment plants, respectively. The results showed that higher microbial population (9-10 x 10(4) cfu/mL) was observed in the secondary clarifier of IWK treatment plant. Among the isolates, 23 isolates were gram-positive bacillus (GPB) and gram-positive cocci (GPC), 19 isolates were gram-negative bacillus (GNB) and gram-negative cocci (GNC), and the rest were undetermined. Gram-negative cocci (GNC) were not found in the isolates from IWK. A total of 15 bacterial strains were selected for effective and efficient sludge bioconversion. All the strains were tested against sludge (1% total suspended solids, TSS) to evaluate the biosolids production (TSS% content), chemical oxygen demand (COD) removal and filtration rate (filterability test). The strain S-1 (IWK1001) showed lower TSS content (0.8% TSS), maximum COD removal (84%) and increased filterability (1.1 min/10 mL of filtrate) of treated sludge followed by the strains S-11, S-14, S-2, S-15, S-13, S-7, S-8, S-4, S-3, S-6, S-12, S-16, S-17 and S-9. The pH values in the fermentation broth were affected by the bacterial cultures and recorded as well. Effective bioconversion was observed during the first three days of sludge treatment.

  9. Utilization of lime-dried sludge for eco-cement clinker production: effects of different feeding points.

    Science.gov (United States)

    Cao, Haihua; Liu, Wei; Xu, Jingcheng; Liu, Jia; Huang, Juwen; Huang, Xiangfeng; Li, Guangming

    2018-02-01

    Co-processing lime-dried sludge (LDS) in cement kilns is an appropriate technique to solve the problem of LDS disposal and promote the sustainable development for cement industry. However, there were limited studies that investigated the effects of feeding points on product quality and cement kiln emissions. In this study, simulated experiments were conducted by dividing the feeding points into high-temperature zones (HTZs) and raw mill (RM). Cement quality and major cement kiln emission characteristics were comprehensively investigated. The results showed that in terms of burnability, compressive strength and microstructure, the optimum co-processing amount of LDS were 9 wt% when feeding at RM, while 6% when feeding at HTZs. Meanwhile, the organic emissions of RM samples were mainly low environmental risk compounds of amides and nitrogenous heterocyclic compounds. Inorganic gaseous pollutions of NO X and SO 2 , respectively, were 8.11 mg/g DS and 12.89 mg/g DS, compared with 7.61 mg/g DS and 4.44 mg/g DS for HTZs. However, all the cement kiln emissions concentration were still much lower than standard requirements. Overall, RM had a bigger LDS co-processing capacity and higher, but acceptable, cement kiln emissions. Feeding LDS via RM could dispose larger amounts of sludge and provide more alternative materials for cement manufacturing.

  10. Leachability Of Heavy Metals From Fly Ash, Slag Of Thermal Power Plant And Treatment Sludge

    Directory of Open Access Journals (Sweden)

    Murat Topal

    2011-12-01

    Full Text Available Fly ash and slag that result from combustion of coal in thermal power plants are important environmental problems; because they contain heavy metals. Sewage sludge that is an ultimate product of wastewater treatment contains pollutants removed from wastewater and these pollutants limits its beneficial usage. The aim of this study is to determine the leachability of some heavy metals from fly ash and slag of power plant and wastewater treatment sludge by Toxicity Characteristic Leaching Procedure (TCLP and American Society of Testing and Materials (ASTM methods. According to TCLP and ASTM results found that the heavy metal concentrations leached to solutions after leaching of the wastes were higher than the limits given by regulation. It was determined that important pollution can be seen as a result of the leaching of these wastes.

  11. Data on metagenomic profiles of activated sludge from a full-scale wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Jianhua Guo

    2017-12-01

    Full Text Available The data in this article mainly present the sequences of activated sludge from a full-scale municipal wastewater treatment plant (WWTP carrying out simultaneous nitrogen and phosphorous removal in Beijing, China. Data include the operational conditions and performance, dominant microbes and taxonomic analysis in this WWTP, and function annotation results based on SEED, Clusters of Orthologous Groups (COG, and Kyoto Encyclopedia of Genes and Genomes (KEGG databases. Sequencing data were generated by using Illumina HiSeq. 2000 platform according to the recommendations of the manufacturer. The sequencing data have been deposited in MG-RAST server (project ID: mgm4735473.3. For more information, see “Unraveling microbial structure and diversity of activated sludge in a full-scale simultaneous nitrogen and phosphorus removal plant using metagenomic sequencing” by Guo et al. (2017 [1].

  12. Environmental biodegradation of halophenols by activated sludge from two different sewage treatment plants.

    Science.gov (United States)

    Smułek, Wojciech; Zdarta, Agata; Kwiczak, Joanna; Zgoła-Grześkowiak, Agnieszka; Cybulski, Zefiryn; Kaczorek, Ewa

    2017-11-10

    Halophenols make a group of aromatic compounds that are resistible to biodegradation by environmental microorganisms. In this study, the biodegradation of 4-bromo-, 4-chloro- and 4-fluorophenols was studied with two types of activated sludges (from a small rural plant and from a bigger municipal plant) as an inoculum. Because of their wide use, surfactants are present in the wastewater and inhibitors enhance the biodegradation of different pollutants; the influence of natural surfactants on halophenols' biodegradation was also tested. Both types of activated sludge contained bacterial strains which were active in the halophenols' biodegradation process. The coexistence of surfactants and halophenols in the wastewater does not prevent microorganisms from effective halophenols' biodegradation. Moreover, surfactants can enhance the effectiveness of halophenols' removal from the environment. Different cell surface modifications of two isolated bacterial strains were observed in the same system of halophenols with or without surfactants. Halophenols and surfactants may also induce changes in bacteria cell surface properties.

  13. Absorption and translocation of polybrominated diphenyl ethers (PBDEs) by plants from contaminated sewage sludge

    Czech Academy of Sciences Publication Activity Database

    Vrkoslavová, J.; Demnerová, K.; Macková, M.; Zemanová, T.; Macek, Tomáš; Hajšlová, J.; Pulkrabová, J.; Hrádková, P.; Stiborová, H.

    2010-01-01

    Roč. 81, č. 3 (2010), s. 381-386 ISSN 0045-6535 R&D Projects: GA MŠk 2B06151 Grant - others:GA ČR(CZ) GP104/08/P188 Institutional research plan: CEZ:AV0Z40550506 Keywords : polybrominated diphenyl ethers * contaminated sewage sludge * plant uptake * bioconcentration factors * Nicotiana tabacum Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.155, year: 2010

  14. Dry matter yield of herbaceous rangeland plants and livemass gain ...

    African Journals Online (AJOL)

    1 in two blocks, and steers in one block were supplemented with phosphorus. Dry matter yield of herbaceous rangeland plants was measured at the end of each growing season from 1984 to 1990 except in 1986, whilst steer livemass was ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Amerine, D.B.

    1982-09-01

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

  16. Sludge stabilization at the Plutonium Finishing Plant, Hanford Site, Richland, Washington

    International Nuclear Information System (INIS)

    1994-10-01

    This Environmental Assessment evaluates the proposed action to operate two laboratory-size muffle furnaces in glovebox HC-21C, located in the Plutonium Finishing Plant (PFP), Hanford Site, Richland, Washington. The muffle furnaces would be used to stabilize chemically reactive sludges that contain approximately 25 kilograms (55 pounds) of plutonium by heating to approximately 500 to 1000 degrees C (900 to 1800 degrees F). The resulting stable powder, mostly plutonium oxide with impurities, would be stored in the PFP vaults. The presence of chemically reactive plutonium-bearing sludges in the process gloveboxes poses a risk to workers from radiation exposure and limits the availability of storage space for future plant cleanup. Therefore, there is a need to stabilize the material into a form suitable for long-term storage. This proposed action would be an interim action, which would take place prior to completion of an Environmental Impact Statement for the PFP which would evaluate stabilization of all plutonium-bearing materials and cleanout of the facility. However, only 10 percent of the total quantity of plutonium in reactive materials is in the sludges, so this action will not limit the choice of reasonable alternatives or prejudice the Record of Decision of the Plutonium Finishing Plant Environmental Impact Statement

  17. Safe use of sewage sludges as plant growth media; Yhdyskuntalietteiden turvallinen loppukaeyttoe

    Energy Technology Data Exchange (ETDEWEB)

    Itaevaara, M. [VTT Biotechnology, Espoo (Finland)

    2005-07-01

    A wide range of chemicals and polymers are used in wastewater treatment plants for phosphorus precipitation and sludge treatment. The inorganic chemicals used include e.g. lime and different types of aluminium and iron based compounds. Polymers are mainly cationic polyacrylamides, which are charged polymers i.e. polyelectrolytes. The aim of this project was to evaluate the environmental risks of these chemicals when sludge is composted and used as plant growth media. The environmental impact of chemicals and polymers was evaluated by collecting information from the literature, manufacturers and waste water treatment plants. In addition, a few commercial polymers were selected for laboratory-scale controlled composting tests. The major emphasis in this project was on the polyacrylamides used in sludge treatment. Polyacrylamides are manufactured from acrylamide, which is a carcinogenic and mutagenic compound. Commercial polyacrylamides also contain residues of acrylamide and other components such as catalysts. During composting harmful degradation products could also be formed. All these factors should be considered when the safety of these products is evaluated. The cationic polyacrylamides studied degraded partly under composting conditions and no acute toxicity was detected by the Vibrio fischerie Flash -test. Furthermore, no harmful effects on the growth of barley and radish were found after two weeks of cultivation. The toxicity, however, should be tested with other test organisms to ensure the safety of these polymers. In addition, the influence of the partly degraded polymer on soil ecology should be further evaluated. (orig.)

  18. Co-production of activated carbon, fuel-gas, and oil from the pyrolysis of corncob mixtures with wet and dried sewage sludge.

    Science.gov (United States)

    Shao, Linlin; Jiang, Wenbo; Feng, Li; Zhang, Liqiu

    2014-06-01

    This study explored the amount and composition of pyrolysis gas and oil derived from wet material or dried material during the preparation of sludge-corncob activated carbon, and evaluated the physicochemical and surface properties of the obtained two types of sludge-corncob-activated carbons. For wet material, owing to the presence of water, the yields of sludge-corncob activated carbon and the oil fraction slightly decreased while the yield of gases increased. The main pyrolysis gas compounds were H2 and CO2, and more H2 was released from wet material than dried material, whereas the opposite holds for CO2 Heterocyclics, nitriles, organic acids, and steroids were the major components of pyrolysis oil. Furthermore, the presence of water in wet material reduced the yield of polycyclic aromatic hydrocarbons from 6.76% to 5.43%. The yield of furfural, one of heterocyclics, increased sharply from 3.51% to 21.4%, which could be explained by the enhanced hydrolysis of corncob. In addition, the surface or chemical properties of the two sludge-corncob activated carbons were almost not affected by the moisture content of the raw material, although their mesopore volume and diameter were different. In addition, the adsorption capacities of the two sludge-corncob activated carbons towards Pb and nitrobenzene were nearly identical. © The Author(s) 2014.

  19. GROWTH AND NODULATION OF LEUCAENA AND PROSOPIS SEEDLINGS IN SOIL PLUS TANNERY SLUDGE

    Directory of Open Access Journals (Sweden)

    Ademir Sérgio Ferreira de Araújo

    2006-01-01

    Full Text Available The objective of this paper was to evaluate the growth and nodulation of Leucaena and Prosopis seedlings in soil plus tannery sludge. The study was conducted in a greenhouse, using bags containing soil plus tannery sludge. Seedlings of Leucaena and Prosopis inoculated with Bradyrhizobium sp were used. Results were evaluated 90 days after plant emergency. The application of tannery sludge, in the rate of 11.250 kg per hectare significantly increased plant height, stem diameter, and above ground dry mass ofLeucaena. Regarding Prosopis, there were no significant increases in these variables with tannery sludge application, except for aerial dry mass. No significant differences were seen between the treatments with sludge and inoculated with Bradyrhizobium sp. as to nodule number and dry mass. Tannery sludge evaluated in this work did not affect nodulation, besides favoring Leucaena and Prosopis seedling growth.

  20. Cost minimization in a full-scale conventional wastewater treatment plant: associated costs of biological energy consumption versus sludge production.

    Science.gov (United States)

    Sid, S; Volant, A; Lesage, G; Heran, M

    2017-11-01

    Energy consumption and sludge production minimization represent rising challenges for wastewater treatment plants (WWTPs). The goal of this study is to investigate how energy is consumed throughout the whole plant and how operating conditions affect this energy demand. A WWTP based on the activated sludge process was selected as a case study. Simulations were performed using a pre-compiled model implemented in GPS-X simulation software. Model validation was carried out by comparing experimental and modeling data of the dynamic behavior of the mixed liquor suspended solids (MLSS) concentration and nitrogen compounds concentration, energy consumption for aeration, mixing and sludge treatment and annual sludge production over a three year exercise. In this plant, the energy required for bioreactor aeration was calculated at approximately 44% of the total energy demand. A cost optimization strategy was applied by varying the MLSS concentrations (from 1 to 8 gTSS/L) while recording energy consumption, sludge production and effluent quality. An increase of MLSS led to an increase of the oxygen requirement for biomass aeration, but it also reduced total sludge production. Results permit identification of a key MLSS concentration allowing identification of the best compromise between levels of treatment required, biological energy demand and sludge production while minimizing the overall costs.

  1. Thermophilic sludge digestion improves energy balance and nutrient recovery potential in full-scale municipal wastewater treatment plants.

    Science.gov (United States)

    De Vrieze, Jo; Smet, Davey; Klok, Jacob; Colsen, Joop; Angenent, Largus T; Vlaeminck, Siegfried E

    2016-10-01

    The conventional treatment of municipal wastewater by means of activated sludge is typically energy demanding. Here, the potential benefits of: (1) the optimization of mesophilic digestion; and (2) transitioning to thermophilic sludge digestion in three wastewater treatment plants (Tilburg-Noord, Land van Cuijk and Bath) in the Netherlands is evaluated, including a full-scale trial validation in Bath. In Tilburg-Noord, thermophilic sludge digestion covered the energy requirements of the plant (102%), whereas 111% of sludge operational treatment costs could be covered in Bath. Thermophilic sludge digestion also resulted in a strong increase in nutrient release. The potential for nutrient recovery was evaluated via: (1) stripping/absorption of ammonium; (2) autotrophic removal of ammonium via partial nitritation/anammox; and (3) struvite precipitation. This research shows that optimization of sludge digestion may lead to a strong increase in energy recovery, sludge treatment costs reduction, and the potential for advanced nutrient management in full-scale sewage treatment plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Hydrogen sulphide removal in the anaerobic digestion of sludge by micro-aerobic processes: pilot plant experience.

    Science.gov (United States)

    Fdz-Polanco, M; Díaz, I; Pérez, S I; Lopes, A C; Fdz-Polanco, F

    2009-01-01

    H(2)S removal from biogas produced in anaerobic digestion of sludge through the introduction of oxygen under micro-aerobic conditions is studied. Research was carried out in two pilot plant reactors (working volume, 200 L each) treating sludge from WWTP with HRT of 20 days. Mixing was provided via sludge or biogas recirculation. Introduction of very low oxygen flow (0.013-0.024 L/L(reactor) d) successfully removed H(2)S content in biogas with an efficiency above 99%. Reactor performance during micro-aerobic operation in terms of biogas production, methane yield and COD removal were not affected by the amount of oxygen supplied, remaining stable and similar to the anaerobic behaviour. Sludge recirculation ( approximately 50 L/h) and biogas recirculation ( approximately 3.5 L/min) as mixing methods were found not significant in H(2)S removal from biogas while biogas recirculation reduced by 10 times dissolved sulphide concentration compared to sludge recirculation.

  3. Effects of sewage sludge amendment on snail growth and trace metal transfer in the soil-plant-snail food chain.

    Science.gov (United States)

    Bourioug, Mohamed; Gimbert, Frédéric; Alaoui-Sehmer, Laurence; Benbrahim, Mohammed; Badot, Pierre-Marie; Alaoui-Sossé, Badr; Aleya, Lotfi

    2015-11-01

    Cu, Zn, Pb, and Cd concentrations in a soil plant (Lactuca sativa) continuum were measured after sewage sludge amendment. The effects of sewage sludge on growth and trace metal bioaccumulation in snails (Cantareus aspersus) were investigated in a laboratory experiment specifically designed to identify contamination sources (e.g., soil and leaves). Application of sewage sludge increased trace metal concentrations in topsoil. However, except Zn, metal concentrations in lettuce leaves did not reflect those in soil. Lettuce leaves were the main source of Zn, Cu, and Cd in exposed snails. Bioaccumulation of Pb suggested its immediate transfer to snails via the soil. No apparent toxic effects of trace metal accumulation were observed in snails. Moreover, snail growth was significantly stimulated at high rates of sludge application. This hormesis effect may be due to the enhanced nutritional content of lettuce leaves exposed to sewage sludge.

  4. Use of Lecane rotifers for limiting Thiothrix filamentous bacteria in bulking activated sludge in a dairy wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Kowalska Ewa

    2014-01-01

    Full Text Available Excessive growth of filamentous bacteria is a serious problem in many dairy wastewater treatment plants (WWTPs. The objective of the study was to determine whether Lecane inermis rotifers were able to reduce the density of Thiothrix bacteria in activated sludge originating from a dairy WWTP, as well as to identify the impact of rotifers on other organisms in sludge. On a laboratory scale, three experiments were conducted in which activated sludge with a predominance of Thiothrix was inoculated with rotifers at an initial concentration of app. 600 individuals/mL. The results showed that the rotifers, by feeding on the bacterium filaments, are able to reduce significantly the quantity of Thiothrix. A decline in Thiothrix abundance coincided with an improvement of the sedimentation properties of activated sludge. In addition, it was proven that Lecane inermis did not negatively affect the number of Protozoa and Metazoa in activated sludge.

  5. Spontaneous plant colonization of brownfield soil and sludges and effects on substrate properties and pollutants mobility

    Science.gov (United States)

    Rocco, Claudia; Agrelli, Diana; Gonzalez, Maria Isabel; Mingo, Antonio; Motti, Riccardo; Stinca, Adriano; Coppola, Ida; Adamo, Paola

    2017-04-01

    This work was done on brownfield soil and sludges from a dismantled steel plant, moderately polluted by heavy metals (mainly Pb and Zn), 1) to analyzed the effects of substrate properties and environmental conditions on spontaneous vegetation; 2) to assess changes in the chemical properties of soils and sludges, with particular reference to the mobility and bioavailability of pollutants, induced by spontaneous plants revegetation. From 2006 to 2011, spontaneous plant colonization was monitored in the presence or absence of acidic peat both inside the degraded brownfield site and after transferal into a nearby Oak Park environment. During the five experimental years the vegetation growth was monitored using phytosociological method and data analyzed statistically. Both substrates, before and after plant growth, were analyzed for main chemical properties. Metals mobility and bioavailability was assessed using single (H2O; DTPA) and sequential extractions (EU-BCR). At the end of the experiment, plant ability to uptake metal was evaluated on selected species. Overall, 57 plant species grew healthily on the substrates. The combination of soil and sludges with peat resulted in an effective revegetation with a sensible increasing of plants biomass. Most of the species were found in the park (91%), showing plant colonization was mainly affected by the immediate environment rather than by substrate properties. Furthermore, after the five years, the substrate properties (pH, O.C.) were slightly affected by plant growth and, although metal pollutants in both substrates are characterized by low water solubility and DTPA availability, after plants growth an increase (even if not significant) of rhizospheric Cu, Fe, Mn and Zn solubility in H2O was detected. Metals speciation indicated a low risk of Pb and Zn mobility being either largely trapped in the mineralogical structure of oxides and silicates and occluded in easily reducible manganese or iron oxides. Restricted metal

  6. Rheological online determination of the organic dry substance concentration of sewage sludge; Rheologische online Bestimmung des oTS-Gehalts von Klaerschlamm

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, P.; Boehm, A.; Fessler, J.; Liebelt, U. [BASF AG, Ludwigshafen am Rhein (Germany); Traegner, U. [Fachhochschule fuer Technik, Mannheim (Germany)

    1999-07-01

    In order to adjust the filter cake to a certain calorific value and to enhance the dehydratability of sludge, ash, carbon and flocculation agents are added to the latter prior to filtration. Dosage of the additives depends on the sludge's content of organic solids, determined in the form of the so-called organic dry substance concentration. In bench-scale and technical-scale experiments on the rheological properties of sewage sludge, a correlation between organic dry substance concentration and rheological properties, especially the liquid limit of sewage sludge, was established. This knowledge was used to develop a measuring technique for online determination of organic dry substance concentration by means of rheology. (orig.) [German] Zur Einstellung eines bestimmten Heizwertes des Filterkuchens und zur Verbesserung der Entwaesserbarkeit werden dem Schlamm vor der Filtration Asche, Kohle und Flockungsmittel zugegeben. Die Dosierung der Zuschlagsstoffe erfolgt in Abhaengigkeit vom Gehalt des Schlamms an organischem Feststoff, bestimmt in Form der sog. oTS-Konzentration. In Labor- und Betriebsversuchen zum rheologischen Verhalten von Klaerschlamm konnte eine Korrelation zwischen der oTS-Konzentration und den Fliesseigenschaften, insbesondere der Fliessgrenze von Klaerschlamm ermittelt werden. Diese Erkenntnis wurde in ein Messverfahren zur online-Bestimmung der oTS-Konzentration mittels Rheologie umgesetzt. (orig.)

  7. Biotransformation of Domestic Wastewater Treatment Plant Sludge by Two-Stage Integrated Processes -Lsb & Ssb

    Directory of Open Access Journals (Sweden)

    Md. Zahangir Alam, A. H. Molla and A. Fakhru’l-Razi

    2012-10-01

    Full Text Available The study of biotransformation of domestic wastewater treatment plant (DWTP sludge was conducted in laboratory-scale by two-stage integrated process i.e. liquid state bioconversion (LSB and solid state bioconversion (SSB processes. The liquid wastewater sludge [4% w/w of total suspended solids (TSS] was treated by mixed filamentous fungi Penicillium corylophilum and Aspergillus niger, isolated, screened and mixed cultured in terms of their higher biodegradation potential to wastewater sludge. The biosolids was increased to about 10% w/w. Conversely, the soluble [i.e. Total dissolve solid (TDS] and insoluble substances (TSS in treated supernatant were decreased effectively in the LSB process. In the developed LSB process, 93.8 g kg-1of biosolids were enriched with fungal biomass protein and nutrients (NPK, and 98.8% of TSS, 98.2% of TDS, 97.3% of turbidity, 80.2% of soluble protein, 98.8% of reducing sugar and 92.7% of chemical oxygen demand (COD in treated sludge supernatant were removed after 8 days of treatment. Specific resistance to filtration (1.39x1012 m/kg was decreased tremendously by the microbial treatment of DWTP sludge after 6 days of fermentation. The treated biosolids in DWTP sludge was considered as pretreated resource materials for composting and converted into compost by SSB process. The SSB process was evaluated for composting by monitoring the microbial growth and its subsequent roles in biodegradation in composting bin (CB. The process was conducted using two mixed fungal cultures, Trichoderma harzianum with Phanerochaete chrysosporium 2094 and (T/P and T. harzianum and Mucor hiemalis (T/M; and two bulking materials, sawdust (SD and rice straw (RS. The most encouraging results of microbial growth and subsequent solid state bioconversion were exhibited in the RS than the SD. Significant decrease of the C/N ratio and germination index (GI were attained as well as the higher value of glucosamine was exhibited in compost; which

  8. Gravity Drainage of Activated Sludge on Reed Beds

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Dominiak, Dominik Marek; Keiding, Kristian

    has therefore been developed to measure relevant quality parameters: specific cake resistance, settling velocity and cake compressibility. It has been found that activated sludge form highly compressible cake even at the low compressive pressures obtained during drainage. Numerical simulation shows...... from the wastewater treatment plant to the red beds may destroy the sludge structure and thereby reduces the dewaterability of sludge. Both the mechanical stress during pumping and anaerobic microbial activity affects the sludge quality. The quality of the sludge can be improved if I) the drying reed...... beds are placed close to the wastewater treatment plant, II) anaerobic condition is avoid e.g. by adding calcium nitrate, and III) the sludge structure is rebuild before it is poured on the reed bed e.g. by adding calcium carbonate...

  9. Experience with a pilot plant for the irradiation of sewage sludge

    International Nuclear Information System (INIS)

    Wizigmann, I.

    1976-01-01

    Reduction of viable micro-organisms could be achieved by irradiation of sewage sludge in a pilot plant ( 60 Co gamma-radiation 300 krad, 300 min.). The reduction amounted to an average of 2 log with Enterococces and total bacterial count and to 5 log with Enterobacteriaceae. Out of 23 sludge batches from digestor II, 21 were free of Salmonella after irradiation. Of 7 sludge batches from digestor I with a higher level of Enterobacteriaceae and Salmonellae, 5 batches still contained Salmonella after treatment. By making some alterations in the pipe system and reloading further cobalt 60-sources, the duration of irradiation could be reduced to 65 min. while maintaining the dose level of 300 krad. Employing this altered procedure, 16 batches from digestor II and 4 from digestor I were irradiated to date. Only in one of 60 samples were Salmonellae detectable. The hygienic effects of the irradiation plant were confirmed by means of model experiment with pure bacterial cultures. Microorganisms of different species as well as strains of the same species differ in their radiosensitivity. Parasitological experiments were conducted with Ascaris suum ova. No embryonation was noted after radiation treatment at a dose of 300 krad. (orig./HK) [de

  10. Variability of zinc, copper and lead contents in sludge of the municipal stormwater treatment plant.

    Science.gov (United States)

    Zubala, Tomasz; Patro, Magdalena; Boguta, Patrycja

    2017-07-01

    Several years of observations enabled us to assess the extent and variability of heavy metal contamination (Zn, Cu and Pb) of the sludge of the municipal stormwater treatment plant (the town of Puławy, Poland). In terms of size (high capacity) and innovation, it is the only facility of this kind in the country. It collects rainwater run-offs from two catchments (separate inlets) with a total area of about 500 ha. The concentration of the analysed metals is characterised by a large spatial and temporal diversity. The reason for this may be differences in the manner and intensity of use of drained surfaces and different hydraulic conditions (of sedimentation) prevailing in the particular treatment devices. The highest pollution was found in sediments in the grit chamber and in the part of the settler from the side of the interceptor supplying sewage, i.e. from the main traffic route of the town (heavy traffic and developed technical infrastructure). The best-quality sludge was retained in the pond for treated wastewater. In the pool of analysed components, the largest share is Zn, which amounts to about 85%. The content of heavy metals limits the possibility of the natural use of sludge from the municipal stormwater treatment plant. In chemical terms, they should be seen as a potentially dangerous waste and undergo remediation.

  11. Hydrogen-Rich Syngas Production from Gasification and Pyrolysis of Solar Dried Sewage Sludge: Experimental and Modeling Investigations

    Directory of Open Access Journals (Sweden)

    Aïda Ben Hassen Trabelsi

    2017-01-01

    Full Text Available Solar dried sewage sludge (SS conversion by pyrolysis and gasification processes has been performed, separately, using two laboratory-scale reactors, a fixed-bed pyrolyzer and a downdraft gasifier, to produce mainly hydrogen-rich syngas. Prior to SS conversion, solar drying has been conducted in order to reduce moisture content (up to 10%. SS characterization reveals that these biosolids could be appropriate materials for gaseous products production. The released gases from SS pyrolysis and gasification present relatively high heating values (up to 9.96 MJ/kg for pyrolysis and 8.02  9.96 MJ/kg for gasification due to their high contents of H2 (up to 11 and 7 wt%, resp. and CH4 (up to 17 and 5 wt%, resp.. The yields of combustible gases (H2 and CH4 show further increase with pyrolysis. Stoichiometric models of both pyrolysis and gasification reactions were determined based on the global biomass formula, CαHβOγNδSε, in order to assist in the products yields optimization.

  12. Hydrogen-Rich Syngas Production from Gasification and Pyrolysis of Solar Dried Sewage Sludge: Experimental and Modeling Investigations

    Science.gov (United States)

    Ghrib, Amina; Friaa, Athar; Ouerghi, Aymen; Naoui, Slim; Belayouni, Habib

    2017-01-01

    Solar dried sewage sludge (SS) conversion by pyrolysis and gasification processes has been performed, separately, using two laboratory-scale reactors, a fixed-bed pyrolyzer and a downdraft gasifier, to produce mainly hydrogen-rich syngas. Prior to SS conversion, solar drying has been conducted in order to reduce moisture content (up to 10%). SS characterization reveals that these biosolids could be appropriate materials for gaseous products production. The released gases from SS pyrolysis and gasification present relatively high heating values (up to 9.96 MJ/kg for pyrolysis and 8.02  9.96 MJ/kg for gasification) due to their high contents of H2 (up to 11 and 7 wt%, resp.) and CH4 (up to 17 and 5 wt%, resp.). The yields of combustible gases (H2 and CH4) show further increase with pyrolysis. Stoichiometric models of both pyrolysis and gasification reactions were determined based on the global biomass formula, CαHβOγNδSε, in order to assist in the products yields optimization. PMID:28856162

  13. Monitoring and troubleshooting of non-filamentous settling and dewatering problems in an industrial activated sludge treatment plant

    DEFF Research Database (Denmark)

    Kjellerup, B. V.; Keiding, Kristian; Nielsen, Per Halkjær

    2001-01-01

    A large industrial activated sludge wastewater treatment plant had temporary problems with settling and dewatering of the sludge. Microscopical investigations revealed that the poor settling properties were not due to presence of filamentous bacteria, but poor floc properties. In order...... at this industrial plant. The described strategy can be useful in general to find and solve many solid/liquid separation problems in activated sludge wastewater treatment plants....... had started after summer closedown. Possible reasons for the changes in floc properties in the process tanks were found by a) analysing change in wastewater composition by evaluating the different production lines in the industrial plant, b) evaluating the operation of the plant, and c) performing...

  14. Results of exploitation of a pilot-plant installation for bituminization of radioactive sludges

    International Nuclear Information System (INIS)

    Golinski, M.; Ksiazak, Z.; Surala, J.; Dziubecki, R.

    1974-01-01

    Results are discussed of exploitation of a pilot-plant installation for bituminization of radioactive sludges of an efficiency of 25 l/h. In a time period of 20 month 120 cycles were carried out in which 60 m 3 of 2-4% sludges from treatment of low-level waste by the phosphate-ferrocyanide method were solidified. The P-60 asphalt was used for bituminization. The bituminization products contained 5-13.5% of mineral substances. Their activity was in the range 5 x 10 -4 - 5 x 10 -3 μCi/g for alpha emitters and 1.2 - 3.8 x 10 -2 μCi/g for beta emitters. (author)

  15. Chemical analysis of sewage sludge of southern sewerage treatment plant (SSTP) Hyderabad for achieving sustainable development in sector of agriculture

    International Nuclear Information System (INIS)

    Qureshi, K.; Shaikh, N.; Ahmed, R.S.; Nawaz, Z.

    2003-01-01

    A study on the chemical analysis of sewage sludge of southern sewerage treatment plant (SSPP) Hyderabad was studied. Chemical analysis on sludge samples collected form the waste stabilization for different micro-nutrients (essential manures, nitrogen, phosphorus, potassium, calcium and magnesium) were conducted in year 1999-2000. These nutrients and metal were detected by reliable analytical method i.e. Kjeldahls method and Atomic Absorption Spectrophotometer. The analysis showed that sewage sludge contained sufficient quantity of primary and secondary nutrients, hence sewage sludge could be utilized as a natural fertilizer. This will not only solve the disposal problem but it would also be environmentally safer way of providing regulators to the plants. (author)

  16. Coagulant recovery from water treatment plant sludge and reuse in post-treatment of UASB reactor effluent treating municipal wastewater.

    Science.gov (United States)

    Nair, Abhilash T; Ahammed, M Mansoor

    2014-09-01

    In the present study, feasibility of recovering the coagulant from water treatment plant sludge with sulphuric acid and reusing it in post-treatment of upflow anaerobic sludge blanket (UASB) reactor effluent treating municipal wastewater were studied. The optimum conditions for coagulant recovery from water treatment plant sludge were investigated using response surface methodology (RSM). Sludge obtained from plants that use polyaluminium chloride (PACl) and alum coagulant was utilised for the study. Effect of three variables, pH, solid content and mixing time was studied using a Box-Behnken statistical experimental design. RSM model was developed based on the experimental aluminium recovery, and the response plots were developed. Results of the study showed significant effects of all the three variables and their interactions in the recovery process. The optimum aluminium recovery of 73.26 and 62.73 % from PACl sludge and alum sludge, respectively, was obtained at pH of 2.0, solid content of 0.5 % and mixing time of 30 min. The recovered coagulant solution had elevated concentrations of certain metals and chemical oxygen demand (COD) which raised concern about its reuse potential in water treatment. Hence, the coagulant recovered from PACl sludge was reused as coagulant for post-treatment of UASB reactor effluent treating municipal wastewater. The recovered coagulant gave 71 % COD, 80 % turbidity, 89 % phosphate, 77 % suspended solids and 99.5 % total coliform removal at 25 mg Al/L. Fresh PACl also gave similar performance but at higher dose of 40 mg Al/L. The results suggest that coagulant can be recovered from water treatment plant sludge and can be used to treat UASB reactor effluent treating municipal wastewater which can reduce the consumption of fresh coagulant in wastewater treatment.

  17. Performance evaluations of steam power plants with dry cooling towers

    International Nuclear Information System (INIS)

    Fortunato, B.; Magi, V.

    1984-01-01

    A theoretical model is presented to design dry cooling tower systems and to evaluate their off-design performances. The influence of the more important design parameters on the tower dimensions is shown. A preliminary ''optimum'' size is predicted by means of a computer code using a simplified cost model. Moreover the influence of the designed cooling system on the performance of thermoelectric and/or nuclear power plants is analysed

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

    Science.gov (United States)

    Tandukar, Madan; Pavlostathis, Spyros G

    2015-12-15

    A bench-scale investigation was conducted to select external organic wastes and mixing ratios for co-digestion with municipal sludge at the F. Wayne Hill Water Resources Center (FWHWRC), Gwinnett County, GA, USA to support a combined heat and power (CHP) project. External wastes were chosen and used subject to two constraints: a) digester retention time no lower than 15 d; and b) total biogas (methane) production not to exceed a specific target level based on air permit constraints on CO2 emissions. Primary sludge (PS), thickened waste activated sludge (TWAS) and digested sludge collected at the FWHWRC, industrial liquid waste obtained from a chewing gum manufacturing plant (GW) and dewatered fat-oil-grease (FOG) were used. All sludge and waste samples were characterized and their ultimate digestibility was assessed at 35 °C. The ultimate COD to methane conversion of PS, TWAS, municipal sludge (PS + TWAS; 40:60 w/w TS basis), GW and FOG was 49.2, 35.2, 40.3, 72.7, and 81.1%, respectively. Co-digestion of municipal sludge with GW, FOG or both, was evaluated using four bench-scale, mesophilic (35 °C) digesters. Biogas production increased significantly and additional degradation of the municipal sludge between 1.1 and 30.7% was observed. Biogas and methane production was very close to the target levels necessary to close the energy deficit at the FWHWRC. Co-digestion resulted in an effluent quality similar to that of the control digester fed only with the municipal sludge, indicating that co-digestion had no adverse effects. Study results prove that high methane production is achievable with the addition of concentrated external organic wastes to municipal digesters, at acceptable higher digester organic loadings and lower retention times, allowing the effective implementation of CHP programs at municipal wastewater treatment plants, with significant cost savings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Ecological and Economic Aspects of the Application of Sewage Sludge in Energetic Plant Plantations - A Swot Analysis

    Science.gov (United States)

    Wójcik, Marta; Stachowicz, Feliks; Masłoń, Adam

    2017-12-01

    Sewage sludge management in Poland is a relatively new field of waste management called "in statu nascendi", the standards of which have not been recognized yet. It also requires the implementation of new solutions in the field of sewage sludge. So far, the most popular method of sewage sludge utilization has been landfill disposal. In line with the restriction placed on landfill waste with a calorific value above 6 MJ/kg introduced on 1 January 2016, agricultural use and thermal methods are particularly applied. Municipal sewage sludge may be successfully used in the cultivation of energetic plant plantations. The aforementioned waste could be treated as an alternative to traditional mineral fertilizers, which in turn might successfully provide valuable nutrients for plants. This paper illustrates the SWOT analysis (Strengths, Weaknesses, Opportunities, and Threats) associated with the use of sewage sludge from Świlcza-Kamyszyn WTTP (Podkarpackie Province, Poland) for agricultural purposes. This analysis could be useful in evaluating the utility of sewage sludge in perennial plant plantations in order to determine the appropriate waste management strategies.

  20. Intensifying drying process with creation of functional plant compositions

    Directory of Open Access Journals (Sweden)

    Zh. Petrova

    2015-05-01

    Full Text Available Introduction. The process of drying agricultural raw products is associated with loss of bioactive substances by the products exposed to heat, light, oxygen, or рН medium. It is reasonable to enhance the table beet processing technology in order to achieve maximum betanin conservation at lower energy consumption. Materials and methods. Table beets, rhubarbs, lemons, and tomatoes were dried at temperature of 50 to 100 ºС, air speed of 1.5 to 3.5 m/s, heat carrier water content of 7 to 15 g/kg, and layer thickness of 2 to 20 mm. The betanіn content was determined via absorption spectra, using the optical density value at 540 nm wavelength. A differential microcalorimeter was used for measuring evaporation heat consumption. Results and discussion.The effect of raw product pre-drying preparation was studied. With no preliminary preparation, the loss of betanin after drying reaches 66 %. The preliminary preparation technology we have developed includes boiling whole root crops with optimal selection of acid medium and allows us to reduce the betanin loss down to 6 %. Regretfully, the process requires large energy consumption. Low energy consumption pre-drying preparation method was developed for antioxidant raw products with thermal processing replaced by blending. The betanin loss, in this case, does not exceed 5 %. Optimal drying temperature of betanin-containing raw stock, after its preliminary processing, is 60 °С. It allows to keep up to 95 % of betanіn. Specific heat consumption for water evaporation out of the developed table beet based antioxidant plant compositions, with addition of rhubarb and lemon, is less by 4 to 5 % as compared to the initial components. Conclusions. Dependence of betanin loss in plant raw stock on the material temperature and composition components, in the course of their pre-drying preparation, was found. It was also found that water evaporation heat, for some antioxidant plant compositions developed, is less

  1. A new approach towards modelling of the carbon degradation cycle at two-stage activated sludge plants.

    Science.gov (United States)

    Winkler, S; Müller-Rechberger, H; Nowak, O; Svardal, K; Wandl, G

    2001-01-01

    A pilot plant has been operated in order to investigate the performance and operating characteristics of the plant concept developed for the extension of the main Vienna STP. Due to the different operational modes included in the plant concept, modelling of the carbon degradation becomes of crucial importance. A new activated sludge model is introduced which combines parts of the carbon degradation model concepts as they have been released in the ASM1-model and the ASM3-model, respectively. A method is presented which utilises results from mass balance calculations and sludge stabilisation experiments to reduce the uncertainty in the determination of the values of the simulation model parameters.

  2. Determination of fluoroquinolone antibacterial agents in sewage sludge and sludge-treated soil using accelerated solvent extraction followed by solid-phase extraction.

    Science.gov (United States)

    Golet, Eva M; Strehler, Adrian; Alder, Alfredo C; Giger, Walter

    2002-11-01

    A method for the quantitative determination of humanuse fluoroquinolone antibacterial agents (FQs) ciprofloxacin and norfloxacin in sewage sludge and sludge-treated soil samples was developed. The accelerated solvent extraction was optimized with regard to solvents and operational parameters, such as temperature, pressure, and extraction time. A 50 mM aqueous phosphoric acid/ acetonitrile mixture (1:1) was found to be optimum in combination with an extraction temperature of 100 degrees C at 100 bar, during 60 and 90 min for sewage sludge and sludge-treated soil samples, respectively. A cleanup step using solid-phase extraction substantially improved the selectivity of the method. Overall recovery rates for FQs ranged from 82 to 94% for sewage sludge and from 75 to 92% for sludge-treated soil, with relative standard deviations between 8 and 11%. Limits of quantification were 0.45 and 0.18 mg/kg of dry matter for sewage sludge and sludge-treated soils, respectively. The presented method was successfully applied to untreated and anaerobically digested sewage sludges and sludge-treated soils. Ciprofloxacin and norfloxacin were determined in sewage sludges from several wastewater treatment plants with concentrations ranging from 1.40 to 2.42 mg/kg of dry matter. Therefore, contrary to what may be expected for human-use pharmaceuticals, FQs may reach the terrestrial environment as indicated by the occurrence of FQs in topsoil samples from experimental fields, to which sewage sludge had been applied.

  3. Effects of natural plant tenderizers on proteolysis and texture of dry ...

    African Journals Online (AJOL)

    , and overall acceptability. From these results, it is shown that those enzymes as a raw plant juices could be used as tenderizers in dry sausage production. Keywords: Dry sausages, wild boar meat, plant enzymes, proteolysis, texture, sensory ...

  4. Anaerobic Codigestion of Municipal Wastewater Treatment Plant Sludge with Food Waste: A Case Study

    Directory of Open Access Journals (Sweden)

    Zubayeda Zahan

    2016-01-01

    Full Text Available The aim of this study was to assess the effects of the codigestion of food manufacturing and processing wastes (FW with sewage sludge (SS, that is, municipal wastewater treatment plant primary sludge and waste activated sludge. Bench scale mesophilic anaerobic reactors were fed intermittently with varying ratio of SS and FW and operated at a hydraulic retention time of 20 days and organic loading of 2.0 kg TS/m3·d. The specific biogas production (SBP increased by 25% to 50% with the addition of 1%–5% FW to SS which is significantly higher than the SBP from SS of 284±9.7 mLN/g VS added. Although the TS, VS, and tCOD removal slightly increased, the biogas yield and methane content improved significantly and no inhibitory effects were observed as indicated by the stable pH throughout the experiment. Metal screening of the digestate suggested the biosolids meet the guidelines for use as a soil conditioner. Batch biochemical methane potential tests at different ratios of SS : FW were used to determine the optimum ratio using surface model analysis. The results showed that up to 47-48% FW can be codigested with SS. Overall these results confirm that codigestion has great potential in improving the methane yield of SS.

  5. Ignored fungal community in activated sludge wastewater treatment plants: diversity and altitudinal characteristics.

    Science.gov (United States)

    Niu, Lihua; Li, Yi; Xu, Lingling; Wang, Peifang; Zhang, Wenlong; Wang, Chao; Cai, Wei; Wang, Linqiong

    2017-02-01

    Fungi are important contributors to the various functions of activated sludge wastewater treatment plants (WWTPs); however, the diversity and geographic characteristics of fungal populations have remained vastly unexplored. Here, quantitative polymerase chain reaction and 454 pyrosequencing were combined to investigate the abundance and diversity of the activated sludge fungal communities from 18 full-scale municipal WWTPs in China. Phylogenetic taxonomy revealed that the members of the fungal communities were assigned to 7 phyla and 195 genera. Ascomycota and Basidiomycota were the most abundant phyla, dominated by Pluteus, Wickerhamiella, and Penicillium. Twenty-three fungal genera, accounting for 50.1 % of the total reads, were shared by 18 WWTPs and constituted a core fungal community. The fungal communities presented similar community diversity but different community structures across the WWTPs. Significant distance decay relationships were observed for the dissimilarity in fungal community structure and altitudinal distance between WWTPs. Additionally, the community evenness increased from 0.25 to 0.7 as the altitude increased. Dissolved oxygen and the C/N ratio were determined to be the most dominant contributors to the variation in fungal community structure via redundancy analysis. The observed data demonstrated the diverse occurrence of fungal species and gave a marked view of fungal community characteristics based on the previously unexplored fungal communities in activated sludge WWTPs.

  6. Polyhydroxyalkanoate (PHA) accumulation potential and PHA-accumulating microbial communities in various activated sludge processes of municipal wastewater treatment plants.

    Science.gov (United States)

    Sakai, K; Miyake, S; Iwama, K; Inoue, D; Soda, S; Ike, M

    2015-01-01

    To clarify the polyhydroxyalkanoate (PHA) accumulation potential and the PHA-accumulating microbial community structure in activated sludge in municipal wastewater treatment plants (WWTPs) and to identify their influential factors. Nine activated sludge samples were collected from municipal WWTPs employing various biological treatment processes. In acetate-fed 24-h batch experiments under aerobic and nitrogen- and phosphorus-limited conditions, polyhydroxybutyrate (PHB) content of activated sludge increased from 0-1·3 wt% to 7·9-24 wt%, with PHB yields of 0·22-0·50 C-mol 3-hydroxybutyrate (C-mol acetate)(-1). Microbial community analyses found that activated sludge samples that accumulated >20 wt% of PHB after 24-h PHA accumulation experiments had >5·0 × 10(8) copies g(-1)-mixed liquor-suspended solid of phaC genes. Results indicated that (i) activated sludge in municipal WWTPs can accumulate up to approx. 20 wt% of PHA without enrichment processes, (ii) PHA accumulation potential of activated sludge varied depending on the operational conditions (treatment processes) of WWTPs, and (iii) phaC gene number can provide a simple indication of PHA accumulation potential. This is the first study to compare the PHA accumulation potential and PHA-accumulating microbial communities in activated sludge of various treatment processes. Our findings may be useful for enhancing the resource recovery potential of wastewater treatment systems. © 2014 The Society for Applied Microbiology.

  7. From municipal/industrial wastewater sludge and FOG to fertilizer: A proposal for economic sustainable sludge management.

    Science.gov (United States)

    Bratina, Božidar; Šorgo, Andrej; Kramberger, Janez; Ajdnik, Urban; Zemljič, Lidija Fras; Ekart, Janez; Šafarič, Riko

    2016-12-01

    After a ban on the depositing of untreated sludge in landfills, the sludge from municipal and industrial water-treatment plants can be regarded as a problem. Waste products of the water treatment process can be a problem or an opportunity - a source for obtaining raw materials. In the European Union, raw sludge and fats, oil and grease (FOG) from municipal and industrial wastewater treatment plants (WWTP) cannot be deposited in any natural or controlled environment. For this reason, it must be processed (stabilized, dried) to be used later as a fertilizer, building material, or alternative fuel source suitable for co-incineration in high temperature furnaces (power plants or concrete plants). The processes of drying sludge, where heat and electricity are used, are energy consuming and economically unattractive. Beside energy efficiency, the main problem of sludge drying is in its variability of quality as a raw material. In addition to this, sludge can be contaminated by a number of organic and inorganic pollutants and organisms. Due to the presence or absence of pollutants, different end products can be economically interesting. For example, if the dried sludge contains coliform bacteria, viruses, helminths eggs or smaller quantities of heavy metals, it cannot be used as a fertilizer but can still be used as a fuel. The objectives of the current article is to present a batch-processing pilot device of sludge or digestate that allows the following: (1) low pressure and low temperature energy effective drying of from 10 to 40% remaining water content, (2) disinfection of pathogen (micro)organisms, (3) heavy metal reduction, (4) production of products of predetermined quality (e.g. containing different quantities of water; it can be used as a fertilizer, or if the percentage of water in the dry sludge is decreased to 10%, then the dried sludge can be used as a fuel with a calorific value similar to coal). An important feature is also the utilization of low

  8. Co-conditioning of the anaerobic digested sludge of a municipal wastewater treatment plant with alum sludge : benefit of phosphorus reduction in reject water

    OpenAIRE

    Yang, Y.; Zhao, Y.Q.; Babatunde, A.O.; Kearney, P.

    2007-01-01

    In this study, alum sludge was introduced into co-conditioning and dewatering with an anaerobic digested activated sludge to examine the role of the alum sludge in improving the dewaterbility of the mixed sludge and also in immobilizing phosphorus in the reject water. Experiments have demonstrated that the optimal mix ratio for the two sludges is 2:1 (anaerobic digested sludge: alum sludge; volume basis), and this can bring about 99% phosphorus reduction in the reject water through the adsorp...

  9. Evaluation of plant-wide WWTP control strategies including the effects of filamentous bulking sludge

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Comas, J.S.; Rodríguez Roda, I.

    2009-01-01

    Model No. 2 (BSM2). In a second series of simulations the parameters of the secondary settler model in the BSM2 are automatically changed on the basis of an on-line calculated risk of filamentous bulking, in order to mimic the effect of growth of filamentous bacteria in the plant. The results...... concentration in both return and waste flow, less biomass in the bioreactors and a reduction of the TSS removal efficiency. The control alternatives using a TSS controller substantially increase the food to microorganisms (F/M) ratio in the bioreactor, thereby reducing both risk and effects of bulking sludge...

  10. Stepwise calibration of the activated sludge model no. 1 at a partially denitrifying large wastewater treatment plant.

    Science.gov (United States)

    Fall, C; Espinosa-Rodriguez, M A; Flores-Alamo, N; van Loosdrecht, M C M; Hooijmans, C M

    2011-11-01

    Activated sludge modeling technology is maturing; however, currently, there exists a great need to increase its use in daily engineering practice worldwide. A good way for building the capacities of the practitioners is to promote good modeling practices and standardize the protocols. In this study, a systematic procedure was proposed to calibrate the Activated Sludge Model No. 1 (ASM1) at a large wastewater treatment plant, by which the model adequately predicted the quality of the effluent and the sludge quantities. A hydraulics model was set up and validated through a tracer test. The Vesilind settling constants were measured and combined with the default value of the flocculent zone settling parameter, to calibrate the clarifiers. A virtual anoxic tank was installed in the return activated sludge to mimic the denitrification occurring in the settlers. In ASM1, the calibrated parameters were only two influent chemical oxygen demand fractions and one kinetic constant (oxygen half-saturation coefficient).

  11. Radioactivity of sludge in Finland in 1987

    International Nuclear Information System (INIS)

    Puhakainen, M.; Rahola, T.

    1989-05-01

    Sewage sludge from municipal wastewater treatment plants was studied to determine its radionuclide concentrations. Measurements were made to find out whether any radionuclides from the nuclear power stations at Loviisa and Olkiluoto and from hospitals and medical laboratories could be detected in sludge additional to those originating from global and Chernobyl fallout. In the treatment process of water, aluminium sulphate sludge is developed at treatment plants using surface water. This kind of sludge was measured since it also concentrates radionuclides. Fallout nuclides from the Chernobyl nuclear power station after the accident predominated in all sewage sludge samples in Finland. In 1987 six different radionuclides originating from the Chernobyl fallout were detected in sewage sludge. In spring when the snow melted and large quantities of run off water flowed into the treatment plants, the activity concentrations clearly increased, but then started decreasing again. At the end of the year the highest measured 137 Cs activity concentrations were below 1000 Bq kg -1 dry weight. The highest activity concentration in sludge originated from iodine used fro medical purposes

  12. Sewage sludge amendment and inoculation with plant-parasitic nematodes do not facilitate the internalization of Salmonella Typhimurium LT2 in lettuce plants.

    Science.gov (United States)

    Fornefeld, Eva; Baklawa, Mohamed; Hallmann, Johannes; Schikora, Adam; Smalla, Kornelia

    2018-05-01

    Contamination of fruits and vegetables with Salmonella is a serious threat to human health. In order to prevent possible contaminations of fresh produce it is necessary to identify the contributing ecological factors. In this study we investigated whether the addition of sewage sludge or the presence of plant-parasitic nematodes foster the internalization of Salmonella enterica serovar Typhimurium LT2 into lettuce plants, posing a potential threat for human health. Greenhouse experiments were conducted to investigate whether the amendment of sewage sludge to soil or the presence of plant-parasitic nematodes Meloidogyne hapla or Pratylenchus crenatus promote the internalization of S. Typhimurium LT2 from soil into the edible part of lettuce plants. Unexpectedly, numbers of cultivable S. Typhimurium LT2 decreased faster in soil with sewage sludge than in control soil but not in root samples. Denaturing gradient gel electrophoresis analysis revealed shifts of the soil bacterial communities in response to sewage sludge amendment and time. Infection and proliferation of nematodes inside plant roots were observed but did not influence the number of cultivable S. Typhimurium LT2 in the root samples or in soil. S. Typhimurium LT2 was not detected in the leaf samples 21 and 49 days after inoculation. The results indicate that addition of sewage sludge, M. hapla or P. crenatus to soil inoculated with S. Typhimurium LT2 did not result in an improved survival in soil or internalization of lettuce plants. Copyright © 2017. Published by Elsevier Ltd.

  13. Sludge recovery apparatus

    International Nuclear Information System (INIS)

    Marmo, A.R.

    1979-01-01

    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)

  14. FMTL x L y L z Dimensional Equation for Sludge Drying Beds ...

    African Journals Online (AJOL)

    On verification using the experimental data obtained from the sewage plant, the theoretical prediction of the derived equation gave a close relationship to the practical values with a correlation of 0.994. The specific resistance from the experimental data was found to increase as the hydrostatic pressure increases numerically ...

  15. Performance evaluation of a large sewage treatment plant in Brazil, consisting of an upflow anaerobic sludge blanket reactor followed by activated sludge.

    Science.gov (United States)

    Saliba, Pollyane Diniz; von Sperling, Marcos

    2017-10-01

    The objective of this study was to evaluate the behaviour of a system comprising an upflow anaerobic sludge blanket reactor followed by activated sludge to treat domestic sewage. The Betim Central sewage treatment plant, Brazil, was designed to treat a mean influent flow of 514 L/s. The study consisted of statistical treatment of monitoring data from the treatment plant covering a period of 4 years. This work presents the concentrations and removal efficiencies of the main constituents in each stage of the treatment process, and a mass balance of chemical oxygen demand (COD) and nitrogen. The results highlight the good overall performance of the system, with high mean removal efficiencies: BOD (biochemical oxygen demand) (94%), COD (91%), ammonia (72%) and total suspended solids (92%). As expected, this system was not effective for the removal of nutrients, since it was not designed for this purpose. The removal of Escherichia coli (99.83%) was higher than expected. There was no apparent influence of operational and design parameters on the effluent quality in terms of organic matter removal, with the exceptions of the BOD load upstream of the aeration tank and the sludge age in the unit. Results suggest that this system is well suited for the treatment of domestic sewage.

  16. Effect of anaerobic digestion and liming on plant availability of phosphorus in iron- and aluminium-precipitated sewage sludge from primary wastewater treatment plants.

    Science.gov (United States)

    Alvarenga, Emilio; Øgaard, Anne Falk; Vråle, Lasse

    2017-04-01

    More efficient plant utilisation of the phosphorus (P) in sewage sludge is required because rock phosphate is a limited resource. To meet environmental legislation thresholds for P removal from wastewater (WW), primary treatment with iron (Fe) or aluminium (Al) coagulants is effective. There is also a growing trend for WW treatment plants (WWTPs) to be coupled to a biogas process, in order to co-generate energy. The sludge produced, when stabilised, is used as a soil amendment in many countries. This study examined the effects of anaerobic digestion (AD), with or without liming as a post-treatment, on P release from Fe- and Al-precipitated sludges originating from primary WWTPs. Plant uptake of P from Fe- and Al-precipitated sludge after lime treatment but without AD was also compared. Chemical characterisation with sequential extraction of P and a greenhouse experiment with barley (Hordeum vulgare) were performed to assess the treatment effects on plant-available P. Liming increased the P-labile fraction in all cases. Plant P uptake increased from 18.5 mg pot -1 to 53 mg P pot -1 with liming of Fe-precipitated sludge and to 35 mg P pot -1 with liming of the digestate, while it increased from 18.7 mg pot -1 to 39 and 29 mg P pot -1 for the Al-precipitated substrate and digestate, respectively. Thus, liming of untreated Fe-precipitated sludge and its digestate resulted in higher P uptake than liming its Al-precipitated counterparts. AD had a negative impact on P mobility for both sludges.

  17. Energy recovery from wastewater treatment plants through sludge anaerobic digestion: effect of low-organic-content sludge.

    Science.gov (United States)

    Zhang, Yuyao; Li, Huan

    2017-09-18

    During anaerobic digestion, low-organic-content sludge sometimes is used as feedstock, resulting in deteriorated digestion performance. The operational experience of conventional anaerobic digestion cannot be applied to this situation. To investigate the feature of low-organic-content sludge digestion and explain its intrinsic mechanism, batch experiments were conducted using designed feedstock having volatile solids (VS) contents that were 30-64% of total solids (TS). The results showed that the accumulative biogas yield declined proportionally from 173.7 to 64.8 ml/g VS added and organic removal rate decreased from 34.8 to 11.8% with decreasing VS/TS in the substrate. The oligotrophic environment resulting from low-organic-content substrates led to decreased microbial activity and a switch from butyric fermentation to propionic fermentation. A first-order model described the biogas production from the batch experiments very well, and the degradation coefficient decreased from 0.159 to 0.069 day -1 , exhibiting a positive relation with organic content in substrate. The results observed here corroborated with data from published literature on anaerobic digestion of low-organic-content sludge and showed that it may not be feasible to recover energy from sludge with an organic content lower than 50% through mono digestion.

  18. Biological treatment of sewage treatment plant sludge by pure bacterial culture with optimum process conditions in a stirred tank bioreactor.

    Science.gov (United States)

    Alam, M Z; Muyibi, Suleyman A; Jamal, P

    2007-09-01

    Biological treatment of sewage treatment plant (STP) sludge by potential pure bacterial culture (Bacillus sp.) with optimum process conditions for effective biodegradation and bioseparation was carried out in the laboratory. The effective and efficient bioconversion was evaluated with the treatment of pure bacterial culture and existing microbes (uninnoculated) in sludge. The optimum process conditions i.e., temperature, 40 degrees C; pH, 6; inoculum, 5% (v/v); aeration, 1 vvm; agitation speed, 50 rpm obtained from the previous studies with chemical oxygen demand COD at 30 mgL(-1) were applied for the biological treatment of sludge. The results indicated that pure bacterial culture (Bacillus sp.) showed higher degradation and separation of treated sludge compared to treatment with the existing mixed microbes in a stirred tank bioreactor. The treated STP sludge by potential pure bacterial culture and existing microbes gave 30% and 11%; 91.2% and 59.1; 88.5% and 52.3%; 98.4% and 51.3%; 96.1% and 75.2%; 99.4% and 72.8% reduction of total suspended solids (TSS, biosolids), COD, soluble protein, turbidity, total dissolved solids (TDS) and specific resistance to filtration (SRF), respectively within 7 days of treatment. The pH was observed at 6.5 and 4 during the treatment of sludge by pure culture and existing microbes, respectively.

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

    Directory of Open Access Journals (Sweden)

    Dariusz Zdebik

    2015-01-01

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

  20. Research about impacts of specific pollutants like herbicides upon microbial activity of activated sludge systems in wastewater treatment plants

    Science.gov (United States)

    Hong, Wei; Liu, Shi-qing; Han, Cong; Chang, Gong-fa; Liu, Bo; Zou, Xiao-feng

    2017-04-01

    The impacts of five types of typical specific pollutants like herbicides (including prometon, propazine, acetochlor, metolachlor and bentazone) upon microbial activity of activated sludge systems in wastewater treatment plants were studied by quantitatively feeding specific pollutants into these systems and measuring changes to specific oxygen uptake rate (SOUR) of the systems. The research results suggest that all these five types of specific pollutants significantly inhibit microbial and aerobic metabolisms of the activated sludge systems. The impacts of these herbicides are arranged as follows according to their degrees: bentazoneactivated sludge by 17.0%, 28.4%, 25.8% and 31.1% respectively. The SOUR declined by 37.1% when the concentration of acetochlor was 10mg/L. Useful lessons may be drawn from this study for controlling concentration of specific pollutants like herbicides in influents of the wastewater treatment plants in pesticide parks.

  1. Relationship soil-water-plant after the dry season in dry Mediterranean areas

    Science.gov (United States)

    Hueso-González, P.; Jiménez-Donaire, V.; Ruiz-Sinoga, J. D.

    2012-04-01

    Preliminary studies have determined the existence of a pluviometric gradient around Mediterranean system, which varies from 240 to 1 100 mm mean annual rainfall. This gradient has an incidence in the physical, chemical and hydrological properties in soils with the same litology. Empiric results conclude that humid eco-geomorphological systems are controlled by biotic processes, whereas in arid eco-geomorphological systems, are abiotic factors which have more importance in soil degradation processes. The study area of the present work is located in Málaga (Andalusia, Spain), in the southern part of the Natural Park "Sierra Tejeda, Almijara y Alhama". There, the mean annual temperature is around 18 °C and the mean rainfall is 650 mm. Predominant vegetation corresponds to the termomediterranean serie Smilaci Mauritanicae-Querceto Rotundifoliae Sigmetum, typical of basic soils. The aim of this study is to analyse the immediate hydrological response of the soil under different vegetation covers, through the analysis of certain properties, all this, under subhumid ombrotipe. A random choice of ten representative plants has been done. These plants, with different sizes, were located in the same Southern slope. The soil samples were taken right beside the plant log, and also within a distance of 0.4 to 1 metre from them, depending on the plant size. The sampling was carried out between the end of the dry season and the beginning of the wet one, after a 20% of the mean annual rainfall had rained. The physical, chemical and hydrological analyzes -both in the field and the laboratory- were: exchange-base, total carbon, cation exchange capacity, soil infiltration capacity, salt content, hydrophobia, organic matter, soil organic carbon, total nitrogen, wetting profile in bared soil, wetting profile under vegetation cover (shrubland), and p.H. Literature reveals that rainfall affects significantly the edafogenetic factors, regarding the pluviometric gradient level. In the

  2. Irradiated Sewage Sludge for Production of Fennel (Foeniculum vulgare L.) Plants in Sandy Soil 2- Seed production, oil content, oil constituents and heavy metals in seeds

    International Nuclear Information System (INIS)

    El-Motaium, R. A.; Abo-El-Seoud, M. A.

    2007-01-01

    Field experiment was conducted to study the impact of irradiated and non-irradiated sewage sludge applied to sandy soil on fennel plants (Foeniculum vulgare L.) productivity. In this regards, four rates of sewage sludge application were used (20, 40, 60 and 80 ton/ha) in addition to the mineral fertilizer treatment (control). Sandy soil amended with sewage sludge showed a promising effect on fennel seed yield. A linear gradual increase in seeds yield was observed as the sludge application rate increases. Seeds production increased by 41% to 308% over the control at 80 t /ha application rate, for non-irradiated and irradiated sewage sludge treatments, respectively. Irradiated sewage sludge treatments showed higher fennel seed yield than non-irradiated sewage sludge treatments.Volatile oil percent exhibited no observable variation due to the use of sewage sludge. A few and limited fluctuations could be observed. However, total oil content (cc/plot) increased due to the increase in seeds yield. The magnitude of increase in volatile oil production in response to the sewage sludge application was parallel to the increase in seeds yield. The GLC measurements of the fennel volatile oil reveal that, the t-anethole is the predominant fraction. However, fenchone was detected in relatively moderate concentration. The applied sewage sludge treatment induced some variations in fennel volatile oil constituents. The t.anethole is relatively higher in volatile oil obtained from plants grown on sandy soil fertilized with non-irradiated sewage sludge than the one fertilized with irradiated sewage sludge or chemical fertilizer. In the meantime, the obtained increase in t.anethole was accompanied by a decline in fenchone content. Seeds heavy metals (Zn, Fe, Pb, Cd) were determined. Under all sludge application rates iron and zinc concentrations were in the normal plant concentration range whereas, Cd concentrations were traces.

  3. Evaluation of the functional activity of activated sludge from local waste water treatment plant in the Arctic region

    Directory of Open Access Journals (Sweden)

    Il'inskiy V. V.

    2017-03-01

    Full Text Available The paper considers characteristics of the activated sludge in the local wastewater treatment plant (LWTP and its ability to purify fully domestic sewage water in the Far North. Biochemical process of destruction of organic pollutants is influenced by a microbial complex functioning in aeration tanks. Taking into account climatic conditions of the region where the organic matter degradation processes are slowed, and lack of control over the operation, efficiency and occupational safety of LWTPs, it seems to be important to study the physiological characteristics of the bacteria used in bioremediation, and their ability to maximize the purifying domestic sewage in the Arctic region. Undue intervention in the biosphere systems leads to disruption of the balance of internal and external ecosystems communications. The goal of research is studying structural determination and functioning of activated sludge bacteriocenosis of LWTP TOPAS-5 (GK "Topol-ECO" in certain physical and chemical conditions of the habitat, and establishing completeness of cleaning process in this treatment plant. The paper considers the structure (quantitative and qualitative composition and function of LWTP activated sludge bacteriocenosis functioning in the Arctic region. The estimation of the activated sludge of full waste water treatment process of the LWTP has been given. The research's results have allowed to identify and determine the bacterial count of physiological groups of microorganisms purified domestic sewage; to isolate from activated sludge the bioflocculant-producing microorganisms' on the experimental medium; to evaluate efficiency of LWTP work in the Arctic region

  4. Evaluation and Source Apportionment of Heavy Metals (HMs in Sewage Sludge of Municipal Wastewater Treatment Plants (WWTPs in Shanxi, China

    Directory of Open Access Journals (Sweden)

    Baoling Duan

    2015-12-01

    Full Text Available Heavy metals (HMs in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index Igeo and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. Igeo classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes.

  5. Evaluation and Source Apportionment of Heavy Metals (HMs) in Sewage Sludge of Municipal Wastewater Treatment Plants (WWTPs) in Shanxi, China.

    Science.gov (United States)

    Duan, Baoling; Liu, Fenwu; Zhang, Wuping; Zheng, Haixia; Zhang, Qiang; Li, Xiaomei; Bu, Yushan

    2015-12-11

    Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index I(geo) and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. I(geo) classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes.

  6. Sludge composting of waste water treatment plant. Compost plant of Vila-Seca (Tarragona); Compostaje de lodos procedentes de la depuracion de aguas residuales. Planta de compostaje de Vila- Seca

    Energy Technology Data Exchange (ETDEWEB)

    Marza Brillas, J.

    1995-12-01

    Composting is a very effective process in waste treatment. Very good results are obtained in mass and volume loss, moisture reduction, organic matter establization as well as making possible agricultural uses for the final product. Some parameters as nutrients (C/N ratio), pH, temperature and oxygen content are pointed as the most important for the process. Some composting systems are mentioned but finally tunnel system is shown as the best. Its great advantage is that measurements from main parameters are given continuously to the control computer, so process optimization is done at the moment. The Vila-Seca sludge composting plant is described. This plant can treat 30.000 tones/year from three water treatment plants. The expected 50% on organic matter reduction and 70% on dry matter content has been achieved after only 3 months since its starting up. Finally, in september 1995 will start the construction of another sludge composting plant were the same technology, belonging to GICOM and represented by G.T.R. in Spain, will be installed.

  7. Computer optimization of dry and wet/dry cooling tower systems for large fossil and nuclear power plants

    International Nuclear Information System (INIS)

    Choi, M.; Glicksman, L.R.

    1979-02-01

    This study determined the cost of dry cooling compared to the conventional cooling methods. Also, the savings by using wet/dry instead of all-dry cooling were determined. A total optimization was performed for power plants with dry cooling tower systems using metal-finned-tube heat exchangers and surface condensers. The optimization minimizes the power production cost. The program optimizes the design of the heat exchanger and its air and water flow rates. In the base case study, the method of replacing lost capacity assumes the use of gas turbines. As a result of using dry cooling towers in an 800 MWe fossil plant, the incremental costs with the use of high back pressure turbine and conventional turbine over all-wet cooling are 11 and 15%, respectively. For a 1200 MWe nuclear plant, these are 22 and 25%, respectively. Since the method of making up lost capacity depends on the situation of a utility, considerable effort has been placed on testing the effects of using different methods of replacing lost capacity at high ambient temperatures by purchased energy. The results indicate that the optimization is very sensitive to the method of making up lost capacity. It is, therefore, important to do an accurate representation of all possible methods of making up capacity loss when optimizating power plants with dry cooling towers. A solution for the problem of losing generation capability by a power plant due to the use of a dry cooling tower is to supplement the dry tower during the hours of peak ambient temperatures by a wet tower. A separate wet/dry cooling tower system with series tower arrangement was considered in this study, and proved to be an economic choice over all-dry cooling where some water is available but supplies are insufficient for a totally evaporative cooling tower

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-09-15

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

  9. Treatment of organic pollutants in coke plant wastewater by the method of ultrasonic irradiation, catalytic oxidation and activated sludge

    NARCIS (Netherlands)

    Ning, Ping; Bart, Hans-Jörg; Jiang, Yijiao; de Haan, A.B.; Tien, C.

    2005-01-01

    The paper deals with the degradation of the organic pollutants in coke plant wastewater by the combination process of ultrasonic irradiation, catalytic oxidation and activated sludge. The effect factors of ultrasonic irradiation on the degradation of the organic pollutants such as saturating gas,

  10. The exploitation of sludge from aggregate plants in the manufacture of porous fired clay bricks

    Directory of Open Access Journals (Sweden)

    Chamorro-Trenado, M. A.

    2016-09-01

    Full Text Available Aggregates (gravel and sand are, after water, the Earth’s second most used natural resource, representing about 50% of all consumed mineral resources. Aggregate production generates a large quantity of waste from the aggregate washing process. This waste is made up of suspended solids – sludge – which has a great environmental impact. It is deposited in huge troughs because of the impossibility of discharging it directly into rivers. Many plants have incorporated decanters and filter presses to separate the solid from the liquid fraction. This paper evaluates the possibility of exploiting the solid fraction (i.e. sludge in the manufacture of fired clay bricks. The added value of these bricks is, on the one hand, the exploitation of sludge as a currently useless waste product, and on the other, the use of this sludge to enhance the physical and mechanical properties of conventional fired clay bricks.Los áridos son la segunda materia prima más consumida en la Tierra después del agua, representando alrededor del 50% de todos los recursos minerales consumidos. El proceso de elaboración de estos áridos genera una gran cantidad de residuos procedentes de su lavado. Se trata de partículas sólidas en suspensión – lodos – de gran impacto ambiental, que se depositan en grandes charcas ante la imposibilidad de verterlos directamente al rio. Muchas empresas han incorporado decantadores y filtros de prensa para separar la fracción solida de la líquida. El presente trabajo evalúa la posibilidad de utilizar la fracción sólida, es decir el barro, para la fabricación de piezas cerámicas. El valor añadido de estas piezas es por un lado el aprovechamiento del barro como producto residual, que en estos momentos es desechable, y por otro, conseguir que este barro mejore las propiedades físico-mecánicas de la cerámica convencional.

  11. CHARACTERIZATION OF THE SLUDGE OF IBN ZIAD CONSTANTINE SEWAGE TREATMENT PLANT FOR ITS LANDSPREADING

    Directory of Open Access Journals (Sweden)

    WASSILA CHEURFI

    2016-04-01

    Full Text Available The purpose of this study was to determine the content of metals elements in the sludge of Ibn Ziad sewage treatment plant of Constantine in order to preserve its quality for subsequent use in agriculture. The use of X-ray fluorescence spectroscopy allowed us to identify the following constituents in this mud: Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Ba, Pb. These elements represent 49.82 % of the total mass of the sludge. The elements present with regulated content limit are chromium, copper, nickel, lead and zinc. They occur respectively with the following concentrations: 0.27 mg·g-1, 0.48 mg·g-1, 0.11 mg·g-1, 0.35 mg·g-1 and 2.70 mg·g-1. We have achieved an extraction for evaluating the concentration of the dissolved nitrate ions, the chemical oxygen demand (COD, and pH. The nitrate ions were transformed into sodium paranitrosalicylate to be dosed by ultraviolet-visible (UV-Vis spectroscopy at 420 nm. The concentration measured was 0.12 mg·g-1. The measuring of the COD issued a value of 0.45 mg·g-1. pH was 7.1.

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

    International Nuclear Information System (INIS)

    Descoins, N.; Deleris, S.; Lestienne, R.; Trouvé, E.; Maréchal, F.

    2012-01-01

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

  13. Coliforms removal in full-scale activated sludge plants in India.

    Science.gov (United States)

    Kazmi, A A; Tyagi, V K; Trivedi, R C; Kumar, Arvind

    2008-05-01

    This paper investigates the removal of coliforms in full-scale activated sludge plants (ASP) operating in northern regions of India. Log2.2 and log2.4 removal were observed for total coliforms (TC) and fecal coliforms (FC), respectively. However, the effluent still contained a significant number of TC and FC which was greater than the permissible limit for unrestricted irrigation as prescribed by WHO. The observations also suggest that extended aeration (EA) process operating under high mixed liquor suspended solids (MLSS) and sludge retention time (SRT) is more efficient in the removal of coliforms. Further attempts have been made to establish the relationship between two key wastewater parameters, i.e. biochemical oxygen demand (BOD) and suspended solids (SS) with respect to fecal and TC. The relationships were observed to be linear with a good coefficient of correlation. The interrelationship of BOD and SS with coliforms manifest that improvement of the microbiological quality of wastewater could be linked with the removal of SS. Therefore, SS can serve as a regulatory tool in lieu of an explicit coliforms standard.

  14. Treating ammonium-rich wastewater with sludge from water treatment plant to produce ammonium alum

    Directory of Open Access Journals (Sweden)

    Wen-Po Cheng

    2016-03-01

    Full Text Available This study applies a process to treat ammonium-rich wastewater using alum-generated sludge form water purification plant, and gain economic benefit by producing ammonium alum (Al(NH4(SO42·12H2O. The factors affecting production of ammonium alum include molar ratio of ammonium to aluminum concentration, sulfuric acid concentration, mixing speed, mixing time, standing time, and temperature. According to the equation for the ammonium removal reaction, the theoretical quantity of ammonium alum was calculated based on initial and final concentrations of ammonium. Then, the weight of ammonium alum crystal was divided by the theoretical weight to derive the recovery ratio. The optimum sludge and sulfuric acid dosage to treat about 17 g L−1 ammonium wastewater are 300 g L−1 and 100 mL L−1, respectively. The optimal dosage for wastewater is molar ratio of ammonium to aluminum of about 1 due to the aluminum dissolving in acidified wastewater. The ammonium removal efficiency is roughly 70% and the maximum recovery ratio for ammonium alum is 93% when the wastewater is mixed for 10 min at the mixing velocity gradient of 100 s−1. Ammonium alum production or ammonium removal can be enhanced by controlling the reaction at low temperatures.

  15. Energy generation in a Microbial Fuel Cell using anaerobic sludge from a wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Vinicius Fabiano Passos

    Full Text Available ABSTRACT In microbial fuel cells (MFCs, the oxidation of organic compounds catalyzed by microorganisms (anode generates electricity via electron transfer to an external circuit that acts as an electron acceptor (cathode. Microbial fuel cells differ in terms of the microorganisms employed and the nature of the oxidized organic compound. In this study, a consortium of anaerobic microorganisms helped to treat the secondary sludge obtained from a sewage treatment plant. The microorganisms were grown in a 250 mL bioreactor containing a carbon cloth. The reactor was fed with media containing acetate (as the carbon source for 48 days. Concomitantly, the electrochemical data were measured with the aid of a digital multimeter and data acquisition system. At the beginning of the MFC operation, power density was low, probably due to slow microorganism growth and adhesion. The power density increased from the 15th day of operation, reaching a value of 13.5 μW cm–2 after ca. 24 days of operation, and remained stable until the end of the process. Compared with data in the literature, this power density value is promising; improvements in the MFC design and operation could increase this value even further. The system investigated herein employed excess sludge as a biocatalyst in an MFC. This opens up the possibility of using organic acids and/or carbohydrate-rich effluents to feed MFCs, and thereby provide simultaneous effluent treatment and energy generation.

  16. Utilization of palm oilsludge in poultry diet: 3. Inclusion of fresh or dried fermented palm oil sludge in broiler’s diet

    Directory of Open Access Journals (Sweden)

    A.P Sinurat

    2001-06-01

    Full Text Available Drying proces, especially with heating often affects the nutritive values of feed ingredients. Therefore, this experiment was designed to study the responses of broiler chickens when fed with ration containing fresh or dried fermented palm oil sludge(FPOS. Experimental diets with different levels of fresh or dried FPOS (5, 10, and 15% equally to dried FPOS were formulated with similar nutrient contents. A control diet with no FPOS was also included. Each diet was fed to 30 broiler chickens (5 replicates of 6 birds for 5 weeks. Performances (body weight, feed consumption, feed conversion, and mortalities of chickens were recorded. Carcass percentage and abdominal fat content was also measured at the end of feeding trial. Data obtained were subjected to analysis of variance in a completely randomized design and different between means were tested by orthogonal contrast procedures. Results of the experiment showed that body weight gain (BWG of control birds was not significantlydifferent with BWG of birds fed with FPOS. Birds fed with dried FLS gain more weight than those fed with fresh FPOS (1048 vs 981 g/bird. Increasing of dietary FPOS levels decreased BWG, but 10% inclusion was still tolerable. Feed consumption of control diet was significantly (P0.05. Conversion of feed dry matter to body weight gain of control diet was not significantly (P>0.05 different with those diets with FPOS. However, dry matter conversion of dried FPOS was significantly better than the fresh FPOS. Increasing levels of FLS from 5 to 15 significantly worsen the feed dry matter conversion but not with inclusion of 10% FPOS. Therefore, it is concluded that there is no superior advantage of feeding fresh FPOS as compared with dried FPOS. Inclusion of 10% dried or fresh FPOS in the diets did not affect growth performances of broiler chickens.

  17. Phyto-dehydration of confined polluted sludge: impacts on C-storage and heavy metal immobilization in plant tissues

    Science.gov (United States)

    Liberati, Dario; Sconocchia, Paolo; Ricci, Anna; Gigliotti, Giovanni; Tacconi, Chiara; De Angelis, Paolo

    2017-04-01

    Transpiration of plants can be used to control or remove water in artificial basins containing polluted flooded sediments (phyto-dehydration), with the aim to reduce the risk of environment contamination due to water/sediment spillage. At the same time plants can reduce the risks associated to the pollutants, reducing their mobility by the adsorption in the rhizosphere, uptake and accumulation in tissues, and providing organiccompounds contributing to bind heavy metals. We tested, at pilot scale, a phytodeydration approach to be applied to a storage pond containing sludge with high zinc and copper concentrations (3200 and 1000 µg/Kg, respectively). The sludge derives from the biodigestion of pig slurries, and for most of the year is covered by a water layer due to rainfall. The phyto-dehydration approach was tested in a two years long mesocosm-scale experiment. Inside the mesocosms we maintained the same sludge/water stratification observed in the pond; the helophyte species Phragmites australis was planted over a floating frame inside half of the mesocosms. Mesocosms with P.australis and control mesocosms without plants, were monitored during the test to assess the water consumption, CO2 and CH4 gas exchanges and plant functioning. At the end of the second year we analysed the changes on the carbon pool of the sludge and the immobilization of heavy metals in the plant tissues. After two years, the total organic carbon content of the sludge has been reduced in the control mesocosms, while in the P. australis mesocosms remain close to the initial values. Zinc and copper immobilization in the plant tissues, was characterised by: a very low concentration of zinc (5 µg/kg ) in leaves, intermediates values in culms and rhizomes (49 and 30 µg/kg) and higher values in roots (222 and 114 µg/kg). In conclusion, in addition to the reduction of the sludge spillage risks, the phyto-dehydration approach based on P. australis reduced the carbon loss of the sludge, and

  18. The response of maize (Zea mays L.) plant assisted with bacterial consortium and fertilizer under oily sludge.

    Science.gov (United States)

    Shahzad, Asim; Saddiqui, Samina; Bano, Asghari

    2016-01-01

    The objective of this study was to evaluate the role of PGPR consortium and fertilizer alone and in combination on the physiology of maize grown under oily sludge stress environment as well on the soil nutrient status. Consortium was prepared from Bacillus cereus (Acc KR232400), Bacillus altitudinis (Acc KF859970), Comamonas (Delftia) belonging to family Comamonadacea (Acc KF859971) and Stenotrophomonasmaltophilia (Acc KF859973). The experiment was conducted in pots with complete randomized design with four replicates and kept in field. Oily sludge was mixed in ml and Ammonium nitrate and Diammonium phosphate (DAP) were added at 70 ug/g and 7 ug/g at sowing. The plant was harvested at 21 d for estimation of protein, proline and antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD). To study the degradation, total petroleum hydrocarbon was extracted by soxhelt extraction and extract was analyzed by GC-FID at different period after incubation. Combined application of consortium and fertilizer enhanced the germination %, protein and, proline content by 90,130 and 99% higher than untreated maize plants. Bioavailability of macro and micro nutrient was also enhanced with consortium and fertilizer in oily sludge. The consortium and fertilizer in combined treatment decreased the superoxide dismutase (SOD), peroxidase dismutase (POD) of the maize leaves grown in oily sludge. Degradation of total petroleum hydrocarbon (TPHs) was 59% higher in combined application of consortium and fertilizer than untreated maize at 3 d. The bacterial consortium can enhanced the maize tolerance to oily sludge and enhanced degradation of total petroleum hydrocarbon (TPHs). The maize can be considered as tolerant plant species to remediate oily sludge contaminated soils.

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

    Science.gov (United States)

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

    2015-04-01

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

  20. Dried whole plant Artemisia annua as an antimalarial therapy.

    Directory of Open Access Journals (Sweden)

    Mostafa A Elfawal

    2012-12-01

    Full Text Available Drugs are primary weapons for reducing malaria in human populations. However emergence of resistant parasites has repeatedly curtailed the lifespan of each drug that is developed and deployed. Currently the most effective anti-malarial is artemisinin, which is extracted from the leaves of Artemisia annua. Due to poor pharmacokinetic properties and prudent efforts to curtail resistance to monotherapies, artemisinin is prescribed only in combination with other anti-malarials composing an Artemisinin Combination Therapy (ACT. Low yield in the plant, and the added cost of secondary anti-malarials in the ACT, make artemisinin costly for the developing world. As an alternative, we compared the efficacy of oral delivery of the dried leaves of whole plant (WP A. annua to a comparable dose of pure artemisinin in a rodent malaria model (Plasmodium chabaudi. We found that a single dose of WP (containing 24 mg/kg artemisinin reduces parasitemia more effectively than a comparable dose of purified drug. This increased efficacy may result from a documented 40-fold increase in the bioavailability of artemisinin in the blood of mice fed the whole plant, in comparison to those administered synthetic drug. Synergistic benefits may derive from the presence of other anti-malarial compounds in A. annua. If shown to be clinically efficacious, well-tolerated, and compatible with the public health imperative of forestalling evolution of drug resistance, inexpensive, locally grown and processed A. annua might prove to be an effective addition to the global effort to reduce malaria morbidity and mortality.

  1. Growth and elemental accumulation of plants grown in acidic soil amended with coal fly ash-sewage sludge co-compost

    Energy Technology Data Exchange (ETDEWEB)

    Wong, J.W.C.; Selvam, A. [Hong Kong Baptist University, Hong Kong (China)

    2009-10-15

    A greenhouse experiment was conducted to evaluate the growth and heavy-metal accumulation of Brassica chinensis and Agropyron elongatum in 10 and 25% ash-sludge co-compost (ASC)-amended loamy acidic soil (pH 4.51) at two different application rates: 20% and 40% (v/v). Soil pH increased, whereas electrical conductivity decreased with the amendment of ASC to soil. Bioavailable Cu, Zn, and Mn contents of ASC-amended soil decreased, whereas Ni, Pb, and B contents increased. Concentrations of bioavailable Cu, Zn, and Mn in sludge compost (SC)-amended soils were 5.57, 20.8, and 8.19 mg kg{sup -1}, respectively. These concentrations were significantly lower than those in soil receiving an application rate of 20 or 25% ASC as 2.64, 8.48, and 5.26 mg kg(-1), respectively. Heavy metals and B contents of the composting mass significantly increased with an increase in ASC application rate from 20 to 40% (6.2 to 16.6 mg kg{sup -1} for 10% ASC- and 9.4 to 18.6 mg kg{sup -1} for 25% ASC-amended soil. However, when the ash content in co-compost increased from 10 to 25% during composting, bioavailable heavy-metal contents decreased. However, B contents increased with an increase in ash content. Addition of co-composts increased the dry-weight yield of the plants, and this increase was more obvious as the ash amendment rate in the co-composts and the ASC application rate increased. In case of B. chinensis, the biomass of 2.84 g/plant for 40% application of 25% ASC was significantly higher than SC (0.352 g/plant), which was 40% application of 10% ASC (0.434 g/plant) treatments. However, in A. elongatum, the differences between biomass of plants grown with 10% (1.34-1.94 g/ plant) and 25% ASC (2.12-2.21 g/plant) were not significantly different. ASC was favorable in increasing the growth of B. chinensis and A. elongatum. The optimal ash amendment to the sludge composting and ASC application rates were at 25 and 20%, respectively.

  2. Zinc Regime in the Sewage Sludge-Soil-Plant System of a City Waste Water Treatment Pond

    OpenAIRE

    Lacatusu Radu; Lacatusu Anca-Rovena; Lungu Mihaela; Stanciu Burileanu Mihaela Monica; Vrînceanu Andrei

    2014-01-01

    The sewage sludge from wastewater treatment plant of Iasi, a city with 300,000 inhabitants, for domestic and industrial origin, was stored in a mud pond arranged on an area of 18,920 m2. Chemical analyzes of the sludge showed that, of all the chemical elements determined, only Zn is found at pollutant level (5739 mg∙kg-1), i.e. almost 30 times more than the maximum allowable limit for Zn in soil and 45 times more than the Zn content of the soil on which the mud pond has been set. Over time, t...

  3. Energy cogeneration in urban sewage treatment plants; Cogeneracion energetica en depuradoras de aguas residuales urbanas

    Energy Technology Data Exchange (ETDEWEB)

    Cazurra Perez, T.

    1997-04-01

    The management of the sludge it produces is a decisive element in designing and urban waste water treatment plant. For a single plant, or several plants that are geographically close together heat-drying the sludge is a viable post-treatment for joint sludge productions of 18,000 tons per year which is the equivalent of a 40,000 m``3/day treatment flow. Energy cogeneration substantially cuts the cost of providing the heat required, enabling the total cost of drying the sludge to be reduced by 40% and creating additional economic benefits. This makes the thermal drying/cogeneration combination and attractive proposition. (Author)

  4. REEMISSION OF MERCURY COMPOUNDS FROM SEWAGE SLUDGE DISPOSAL

    Directory of Open Access Journals (Sweden)

    Beata Janowska

    2016-12-01

    Full Text Available The sewage sludge disposal and cultivation methods consist in storage, agricultural use, compost production, biogas production or heat treatment. The sewage sludge production in municipal sewage sludge treatment plants in year 2013 in Poland amounted to 540.3 thousand Mg d.m. The sewage sludge for agricultural or natural use must satisfy chemical, sanitary and environmental safety requirements. The heavy metal content, including the mercury content, determines the sewage sludge disposal method. Mercury has a high chemical activity and biological form compounds with different properties. The properties of the mercury present in sewage sludge or composts, its potential bioavailability depend on its physicochemical forms. Different forms of mercury, which are found in soil and sediments and sewage sludge, may be determined using various techniques sequential extraction. In order to assess the bioavailability the analysis of fractional of mercury in samples of sewage sludge and composts was made. For this purpose the analytical procedure based on a four sequential extraction process was applied. Mercury fractions were classified as exchangeable (EX, base soluble (BS, acids soluble (AS and oxidizable (OX. This article presents the research results on the mercury compounds contents in sewage sludge subjected to drying process, combustion and in composted sewage sludge. During drying and combustion process of the sewage sludge, mercury transforms into volatile forms that could be emitted into the atmosphere. The mercury fractionation in composted sewage sludge proved that mercury in compost occurs mainly in an organic fraction and in a residual fraction that are scarce in the environment.

  5. The binary cycle for dry-coolant electric power plants

    International Nuclear Information System (INIS)

    Jaumotte, A.L.; Gaivao, A.

    1983-01-01

    Steadily growing water requirements have led the designers of large nuclear power plants to consider the use of a dry coolant seriously in the future (since the problem of a water shortage has already emerged). Two fluids are selected, ammonia and freon 22. In fact, this represents a binary cycle, either with ammonia or with freon (phase change heat transfer fluid). Freon 22 offers the major advantage over ammonia of great chemical stability. It is also nonflammable and nontoxic. Moreover, the use of a phase change fluid offers the possibility of reducing the difference between the air temperature and the steam condensation temperature, since exchange in the condenser is isothermal. The feasibility of the mechanical components, and the successful progress of experiments under way, tend to show that the binary cycle may be a highly attractive answer to the problem of water availability [fr

  6. The Efficiency of Anaerobic Digesters on Microbial Quality of Sludge in Isfahan and Shahinshahr Waterwaste Treatment Plant

    Directory of Open Access Journals (Sweden)

    A Takdastan, H Movahedian, N Jafarzadeh, B Bina

    2005-01-01

    Full Text Available Anaerobic digestion is among the oldest processes used for stabilization of solid and biosolids. In this survey 12 samples were taken from the digested anaerobic sludge of Isfahan and ShahinShahr WWTP and total solids, volatile solids, total coliform, fecal coliform, Salmonella and viable parasite ova tests were done. Results were compared with the 503 sections of the 40 CFR regulation of the US EPA .The result showed that the average reduction rate was 30% for volatile solids, 4.5×107 MPN/g. dry solids (DS for total coliform, 5.6×106MPN/g.DS for fecal coliform, 24MPN/4g.DS for Salmonella, and 27 number/4g.DS for viable parasite ova of digested anaerobic sludge in Isfahan. In Shahinshahr WWTP, the average of reduction was 39% in volatile solids, 2.13× 107MPN /g.DS in total coliform, 1.16×106 MPN /g.DS in fecal coliform ,11 MPN/4g.DS in Salmonella and 16 number/4g.DS for viable parasite ova of digested anaerobic sludge . Therefore the digested sludge in Isfahan did not meet the requirements of pathogen reduction in class A and B as well as the reduction requirements for vector attraction, while the digested sludge in ShahinShahr met the requirements of pathogen reduction in class B and vector attraction. So, agricultural use of digested sludge should be made by limiting the kind of crops as well as controlling the harvesting time. The results from the two anaerobic digesters of Isfahan and Shahin Shahr showed that there was a significance correlation between the reduction of volatile solids with total coliform, fecal coliform and Salmonella (P0.9 , while there was no significance correlation between the reduction of volatile solids and viable parasite ova.

  7. Nitrous oxide emissions from an intermittent aeration activated sludge system of an urban wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    William Z. de Mello

    2013-01-01

    Full Text Available This study investigated the emission of N2O during the sequential aerated (60-min and non-aerated (30-min stages of an intermittent aeration cycle in an activated sludge wastewater treatment plant (WWTP. N2O emission occurred during both stages; however, emission was much higher during aeration. Air stripping is the major factor controlling transfer of N2O from the sewage to the atmosphere. The N2O emissions exclusively from the aeration tank represented 0.10% of the influent total nitrogen load and the per capita emission factor was almost 3 times higher than that suggested by the IPCC for inventories of N2O emission from WWTPs.

  8. Activated sludge wastewater treatment plant modelling and simulation: state of the art

    DEFF Research Database (Denmark)

    Gernaey, Krist; Loosdrecht, M.C.M. van; Henze, Mogens

    2004-01-01

    , providing researchers and practitioners with a standardised. set of basis models. This paper introduces the nowadays most frequently used white-box models for description of biological nitrogen and phosphorus removal activated sludge processes. These models are mainly applicable to municipal wastewater......This review paper focuses on modelling of wastewater treatment plants (WWTP). White-box modelling is widely applied in this field, with learning, design and process optimisation as the main applications. The introduction of the ASM model family by the IWA task group was of great importance...... systems, but can be adapted easily to specific situations such as the presence of industrial wastewater. Some of the main model assumptions are highlighted, and their implications for practical model application are discussed. A step-wise procedure leads from the model purpose definition to a calibrated...

  9. Radioactivity of sludge in Finland in 1988-1990

    International Nuclear Information System (INIS)

    Puhakainen, M.; Rahola, T.

    1991-06-01

    Sludge samples from wastewater treatment plants were studied by the Finnish Centre for Radiation and Nuclear Safety from 1979 onwards. Sampling of sludge was extended to include more sewage treatment plants after the accident at the Chernobyl nuclear power station. The study was continued in some of the wastewater treatment plants in order to continuously follow the level of and changes in the fallout radioactivity. Sludge samples were also taken from treatment plants in communities close to the nuclear power stations at Loviisa and Olkiluoto. For a long time the most frequently detected nuclide in sewage sludge was 137 Cs originating from Chemobyl. The 137 Cs activity concentration in sludge varied in 1988 from 68 to 750, in 1989 from 16 to 480 and in 1990 from 11 to 300 Bq kg - 1 dry weight. The activation products in sludge originating from nuclear power stations in Finland were some becquerels per kilo, at the most about twenty becquerels per kilo dry weight. The most frequently detected medical radionuclide was 131 I, frequently detected in almost all wastewater treatment plants

  10. Zinc Regime in the Sewage Sludge-Soil-Plant System of a City Waste Water Treatment Pond

    Directory of Open Access Journals (Sweden)

    Lacatusu Radu

    2014-10-01

    Full Text Available The sewage sludge from wastewater treatment plant of Iasi, a city with 300,000 inhabitants, for domestic and industrial origin, was stored in a mud pond arranged on an area of 18,920 m2. Chemical analyzes of the sludge showed that, of all the chemical elements determined, only Zn is found at pollutant level (5739 mg∙kg-1, i.e. almost 30 times more than the maximum allowable limit for Zn in soil and 45 times more than the Zn content of the soil on which the mud pond has been set. Over time, the content of Zn in the mud pond, but also from soil to which it has been placed, has become upper the normal content of the surrounding soil up to a depth of 260 cm. On the other hand, the vegetation installed on sewage sludge in the process of mineralization, composed predominantly of Phragmites, Rumex, Chenopodium, and Aster species had accumulated in roots, stems and leaves Zn quantities equivalent to 1463 mg Kg-1, 3988 mg Kg-1, 1463 mg Kg-1, respectively, 1120 mg∙Kg-1. The plants in question represents the natural means of phytoremediation, and sewage sludge as such may constitute a fertilizer material for soils in the area, on which Zn deficiency in maize has been recorded. In addition, the ash resulted from the incineration of plants loaded with zinc may constitute, in its turn, a good material for fertilizing of the soils that are deficient in zinc.

  11. Development of effluent removal prediction model efficiency in septic sludge treatment plant through clonal selection algorithm.

    Science.gov (United States)

    Ting, Sie Chun; Ismail, A R; Malek, M A

    2013-11-15

    This study aims at developing a novel effluent removal management tool for septic sludge treatment plants (SSTP) using a clonal selection algorithm (CSA). The proposed CSA articulates the idea of utilizing an artificial immune system (AIS) to identify the behaviour of the SSTP, that is, using a sequence batch reactor (SBR) technology for treatment processes. The novelty of this study is the development of a predictive SSTP model for effluent discharge adopting the human immune system. Septic sludge from the individual septic tanks and package plants will be desuldged and treated in SSTP before discharging the wastewater into a waterway. The Borneo Island of Sarawak is selected as the case study. Currently, there are only two SSTPs in Sarawak, namely the Matang SSTP and the Sibu SSTP, and they are both using SBR technology. Monthly effluent discharges from 2007 to 2011 in the Matang SSTP are used in this study. Cross-validation is performed using data from the Sibu SSTP from April 2011 to July 2012. Both chemical oxygen demand (COD) and total suspended solids (TSS) in the effluent were analysed in this study. The model was validated and tested before forecasting the future effluent performance. The CSA-based SSTP model was simulated using MATLAB 7.10. The root mean square error (RMSE), mean absolute percentage error (MAPE), and correction coefficient (R) were used as performance indexes. In this study, it was found that the proposed prediction model was successful up to 84 months for the COD and 109 months for the TSS. In conclusion, the proposed CSA-based SSTP prediction model is indeed beneficial as an engineering tool to forecast the long-run performance of the SSTP and in turn, prevents infringement of future environmental balance in other towns in Sarawak. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. [Analysis on the target product from sewage sludge pyrolysis and experiments on using the char for enhancing plant cultivation].

    Science.gov (United States)

    Song, Xue-Ding; Chen, De-Zhen; Wang, Zhong-Hui; He, Wei

    2011-09-01

    Characteristics of sewage sludge pyrolysis under low temperatures were studied and the influences of reaction temperature and moisture content on products distribution and their properties were also investigated with a purpose to select a proper target product. After a dissective comparison, char produced from the pyrolysis process was chosen as the target product and then its effect on plant cultivation was checked by using it to plant garlic when blended into normal soil; also its heavy metals contents and their transfer to the garlic were investigated. The primary research results showed that with the moisture content reduced to a certain level, char production was above 40% of sewage sludge when the pyrolysis process took place under 550 degrees C; ash content of the char is around 60% - 65%, but it is rich with nitrogen, phosphorus and potassium contents. The heavy metal contents in the char meet up with the limitations for land use, and the garlic stems planted in the soil blended with the char grew much faster than those planted in normal soil with their averaged height being 3-4 cm higher; however the heavy metal contents in the fast-growing garlic stems were a little higher than that in the normal ones, which was not suitable for edible plants. The results obtained suggested that char produced from sewage sludge pyrolysis process could be a target product arranged for land use especially for non-edible plant cultivation.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

  14. Preliminary studies on the use of irradiation for decontaminating water and sludge in wastewater treatment plants in Chile

    International Nuclear Information System (INIS)

    Villanueva, Loreto; Schrader, Rosemarie

    1999-01-01

    This work describes the activities carried out to date by the Chilean Nuclear Energy Commission, CCHEN, in prospecting the application of gamma and electron beam irradiation to the decontamination of sewage water and sludge in the country. Sludge, in particular, will become a relevant environmental problem in the coming years, because of the large amounts that will be generated, due to the construction of many wastewater treatment plants in the country. The main study consisted of experimental gamma irradiation tests on representative samples of digested sludge from two pilot wastewater treatment plants operating in Santiago. This study showed the technical feasibility of using low irradiation doses, of around 2-3 kGy to significantly reduce the pathogen content in this sludge. Preliminary tests were also carried out to determine that the disinfected sludge was fit for agricultural use due to its nutrient content. A preliminary technical and economic evaluation is being prepared on the use of gamma irradiation for sludge disinfection, as a complement to the experimental studies. With this evaluation a feasible process has been outlined for using gamma irradiation in conjunction with conventional processes for the sludge disinfection or hygienization in domestic wastewater treatment plants, in order to produce a useful material for agricultural use that meets the demanding EPA standards when classified as class A sludge, which permits agricultural use without sanitary restrictions. Several evaluations have been made to determine the potential use of irradiation for water and industrial wastewater effluents decontamination, considering normative standards as well as technical and economic aspects. One of these has been the preliminary evaluation of using electron beam irradiation for disinfecting drinking water, which has the technical advantage of preventing the formation of trihalomethanes, that occur in water chlorination due to the presence of natural humic

  15. Evaluating energy efficient strategies and product quality for distillers' dried grains with solubles (DDGS) in dry-grind ethanol plants

    Science.gov (United States)

    Lan, Tian

    The drying of distillers dried grains with solubles (DDGS), a coproduct of dry-grind corn processing to ethanol utilizes about 30% of the total energy required for the production of a liter of fuel ethanol. Therefore, improving DDGS drying energy efficiency could have significant impact on the economics of the dry-grind corn-to-ethanol process. Drying process improvements must take account into the effects of various drying strategies on the final quality of DDGS which is primarily utilized as a feed ingredient. Previous studies in the literature have shown that physical and chemical properties of DDGS vary according to the ratio of the two primarily feed streams, wet distillers grains (WDG) and condensed distillers solubles (CDS) which make up DDGS. Extensive research using plant-scale and bench-scale experiments have been conducted on the effect of process variables (ratios of WDG, CDS and DDGS add-back) during drying on the physical and chemical properties of DDGS. However, these investigations did not correlate the product characteristics data to drying efficiency. Additionally, it cannot be clearly determined from the literature on DDGS drying that processes used in the industry are optimized for both product quality and energy efficiency. A bench-scale rotary drum dryer heated by an electrically powered heat gun was used to investigate the effects of WDG, CDS and add-back ratios on both energy efficiency, drying performance and DDGS physical and chemical properties. A two stage drying process with the bench-scale rotary dryer was used to simulate the drying of DDGS using ICM (ICM, Inc., Colwich, KS) dry-grind process technology for DDGS drying which uses two rotary drum dryers in series. Effects of drying process variables, CDS content (0, 10, 20 and 40% by mass) and percent DDGS add-back (0, 20, 40 and 60% by mass) on energy performance and product quality were determined. Sixteen different drying strategies based on drying process variable ratios were

  16. Utilization of urban sewage sludge: Chinese perspectives.

    Science.gov (United States)

    Chen, H; Yan, S-H; Ye, Z-L; Meng, H-J; Zhu, Y-G

    2012-06-01

    Urbanization and industrialization in China has resulted in a dramatic increase in the volume of wastewater and sewage sludge produced from wastewater treatment plants. Problems associated with sewage sludge have attracted increasing attention from the public and urban planners. How to manage sludge in an economically and environmentally acceptable manner is one of the critical issues that modern societies are facing. Sludge treatment systems consist of thickening, dewatering, and several different alternative main treatments (anaerobic digestion, aerobic digestion, drying, composting, and incineration). Agricultural application, landfill, and incineration are the principal disposal methods for sewage sludge in China. However, sewage sludge disposal in the future should focus on resource recovery, reducing environmental impacts and saving economic costs. The reuse of biosolids in all scenarios can be environmentally beneficial and cost-effective. Anaerobic digestion followed by land application is the preferable options due to low economic and energy costs and material reuse. It is necessary to formulate a standard suitable for the utilization of sewage sludge in China.

  17. Utilization of palm oil sludge in poultry diet. 1. Dried palm oil sludge and its fermented product in broiler’s diet

    Directory of Open Access Journals (Sweden)

    A.P Sinurat

    2000-06-01

    Full Text Available Palm oil sludge a by product of palm oil industry is not commonly used in poultry feed due to some limiting factors such as low protein and amino acids content and high fiber content. These limiting factors were expected to be reduced by fermentation technology. Therefore an experiment was conducted to study the use of fermented (FLS and non-fermented palm oil sludge (LS for broiler chicken feed. Two hundred and ten day-old broiler chicks were used for this study. The birds were allocated into 35 cages with 6 birds in each cage. Each 5 group of birds were fed with one of 7 experimental diets. All diets were formulated with similar nutrient contents containing either LS or FLS at 3 different levels (5, 10 and 15% and a control diet with no LS or FLS. The experimental diets were fed for 6 weeks and the performances were observed. Carcass yield, abdominal fat, weight of liver and gizzard were also measured at the end of the trial. The results showed that LS or FLS can be included in broiler’s diet, since the mortality, carcass yield, abdominal fat, liver and gizzard were not significantly affected. Best level inclusion of LS was 5%. Although inclusion of 10-15% LS did not affect growth and feed conversion significantly, the feed intake was significantly depressed. The best level inclusion of FLS was 10%, since higher level (15% caused growth depression.

  18. Leito de drenagem: sistema natural para redução de volume de lodo de estação de tratamento de água Draining beds: natural system for sludge volume reduction in the water treatment plant

    Directory of Open Access Journals (Sweden)

    Cali Laguna Achon

    2008-03-01

    Full Text Available As Estações de Tratamento de Água (ETAs tem funcionamento semelhante a uma indústria e podem em diversas etapas gerar resíduos que, na maioria das ETAs, são lançados nos corpos d’água sem tratamento. Neste trabalho avaliou-se o desempenho de Leitos de Drenagem, para o desaguamento de lodo, provenientes de ETAs de ciclo completo que empregam sulfato de alumínio e cloreto de polialumínio (PACl, como coagulantes. Analisou-se as características, a drenagem e secagem dos amostras de lodo e característica do drenado. Os Leitos de Drenagem mostraram-se eficientes para desaguamento e redução de volume de lodo de ETA, de forma natural, sem consumo de energia ou adição de produtos químicos. Obteve-se, aos sete dias, reduções da ordem de 87 % em volume para os lodos de PACl e 83 % para o lodo de Sulfato de Alumínio e teor de sólidos totais 28% e 31% respectivamente.In this work the performance of Draining Beds for sludge dewatering was assessed. The sludge was provided from full cycle Water Treatment Plants (WTPs that employ aluminum sulfate and polyaluminium chloride (PACl as coagulants. The characteristics, drainage and drying of samples of sludge and characteristic of drained were analysed. The Draining Beds were shown to be efficient for dewatering and sludge volume reduction in the WTP, in a natural way, without energy consumption or adding of chemical products. On the seventh day, it was possible to obtain reduction around 87% in volume for PACl sludge and 83% for the aluminum sulfate sludge and total solids content of 28 and 31% respectively.

  19. Effects of different drying processes on the concentrations of metals and metalloids in plant materials

    International Nuclear Information System (INIS)

    Anawar, H.M.; Canha, N.; Freitas, M.C; Santa Regina, I.; Garcia-Sanchez, A.

    2011-01-01

    The drying process of fresh plant materials may affect the porous structure, dehydration and a number of quality characteristics of these materials. Therefore, this study has investigated the effect of different drying processes on the variation of metal and metalloid concentrations in the dried plant materials. Seven varieties of native plant species collected from Sao Domingos mine were analyzed by instrumental neutron activation analysis (INAA) to investigate the effects of freeze-drying (FD), ambient air-drying (AAD) and oven-drying (OD) process on the concentrations of metals and metalloids in the plant biomass. Comparison of ambient air-dried, oven-dried and freeze-dried preparations allows a phenomenological description of the dehydration artefacts. In the quantitative analysis of metals and metalloids, FD and OD plant samples show the higher concentrations of metals and metalloids when compared to those in the AAD plant biomass. The freeze-drying process is comparatively reliable for determination of metals and metalloids concentrations in plant materials. (author)

  20. ASSESSMENT OF THE POSSIBILITIES OF AGRICULTURAL USE OF SEWAGE SLUDGE FROM WASTEWATER TREATMENT PLANTS IN OLECKO

    Directory of Open Access Journals (Sweden)

    Magdalena Filkiewicz

    2015-03-01

    Full Text Available According to the National Waste Management Plan 2014 (NWMP 2014 recommended method of utilization of sewage sludge is using it for agricultural purposes or for land reclamation. The sludge is characterized by a high content of organic substances, microelements and biogenic compounds, through which sewage sludge possess high soil formation and fertilization properties. It is assumed that in 2020 approximately 30% of the sludge production will be used for agricultural purposes, while 15% will be used for land reclamation. We have to remember that prior to the introduction of sludge into the ground, security, health and chemical requirements should be met. In order to use the sludge for agricultural purposes, the process of their disposal should be previously carried out e.g. Autoheated Thermophilic Aerobic Digestion (ATAD. It allows for hygienisation of sewage sludge and reducing the heavy metal content. As a result, processed sewage sludge is characterized by the presence of heavy metals in amounts which do not exceed the standards. It is also deprived of microorganisms. The stabilized sludge is characterized by high phosphorus and calcium content. Therefore there is possibility to use the examined sludge in agriculture.

  1. Cost estimation and economical evaluation of three configurations of activated sludge process for a wastewater treatment plant (WWTP) using simulation

    Science.gov (United States)

    Jafarinejad, Shahryar

    2017-09-01

    The activated sludge (AS) process is a type of suspended growth biological wastewater treatment that is used for treating both municipal sewage and a variety of industrial wastewaters. Economical modeling and cost estimation of activated sludge processes are crucial for designing, construction, and forecasting future economical requirements of wastewater treatment plants (WWTPs). In this study, three configurations containing conventional activated sludge (CAS), extended aeration activated sludge (EAAS), and sequencing batch reactor (SBR) processes for a wastewater treatment plant in Tehran city were proposed and the total project construction, operation labor, maintenance, material, chemical, energy and amortization costs of these WWTPs were calculated and compared. Besides, effect of mixed liquor suspended solid (MLSS) amounts on costs of WWTPs was investigated. Results demonstrated that increase of MLSS decreases the total project construction, material and amortization costs of WWTPs containing EAAS and CAS. In addition, increase of this value increases the total operation, maintenance and energy costs, but does not affect chemical cost of WWTPs containing EAAS and CAS.

  2. Molecular characterization of activated sludge from a seawater‐processing wastewater treatment plant

    Science.gov (United States)

    Sánchez, Olga; Garrido, Laura; Forn, Irene; Massana, Ramon; Maldonado, Manuel Ignacio; Mas, Jordi

    2011-01-01

    Summary The prokaryotic community composition of activated sludge from a seawater‐processing wastewater treatment plant (Almeria, Spain) was investigated by using the rRNA approach, combining different molecular techniques such as denaturing gradient gel electrophoresis (DGGE), clone libraries and in situ hybridization (FISH and CARD‐FISH). Most of the sequences retrieved in the DGGE and the clone libraries were similar to uncultured members of different phyla. The most abundant sequence recovered from Bacteria in the clone library corresponded to a bacterium from the Deinococcus–Thermus cluster (almost 77% of the clones), and the library included members from other groups such as the Alpha, Gamma and Delta subclasses of Proteobacteria, the Bacteroidetes and Firmicutes. Concerning the archaeal clone library, we basically found sequences related to different orders of methanogenic Archaea, in correspondence with the recovered DGGE bands. Enumeration of DAPI (4′,6‐diamidino‐2‐phenylindole) stained cells from two different activated sludge samples after a mechanical flocculation disruption revealed a mean cell count of 1.6 × 109 ml−1. Around 94% of DAPI counts (mean value from both samples) hybridized with a Bacteria specific probe. Alphaproteobacteria were the dominant bacterial group (36% of DAPI counts), while Beta‐, Delta‐ and Gammaproteobacteria, Bacteroidetes, Actinobacteria and Firmicutes contributed to lower proportions (between 0.5–5.7% of DAPI counts). Archaea accounted only for 6% of DAPI counts. In addition, specific primers for amplification of the amoA (ammonia monooxygenase) gene were used to detect the presence of Beta, Gamma and archaeal nitrifiers, yielding positive amplifications only for Betaproteobacteria. This, together with negative in situ hybridizations with probes for well‐known nitrifiying bacteria, suggests that nitrification is performed by still undetected microorganisms. In summary, the combination of the

  3. 454 Pyrosequencing reveals bacterial diversity of activated sludge from 14 sewage treatment plants

    Science.gov (United States)

    Zhang, Tong; Shao, Ming-Fei; Ye, Lin

    2012-01-01

    Activated sludge (AS) contains highly complex microbial communities. In this study, PCR-based 454 pyrosequencing was applied to investigate the bacterial communities of AS samples from 14 sewage treatment plants of Asia (mainland China, Hong Kong, and Singapore), and North America (Canada and the United States). A total of 259 K effective sequences of 16S rRNA gene V4 region were obtained from these AS samples. These sequences revealed huge amount of operational taxonomic units (OTUs) in AS, that is, 1183–3567 OTUs in a sludge sample, at 3% cutoff level and sequencing depth of 16 489 sequences. Clear geographical differences among the AS samples from Asia and North America were revealed by (1) cluster analyses based on abundances of OTUs or the genus/family/order assigned by Ribosomal Database Project (RDP) and (2) the principal coordinate analyses based on OTUs abundances, RDP taxa abundances and UniFrac of OTUs and their distances. In addition to certain unique bacterial populations in each AS sample, some genera were dominant, and core populations shared by multiple samples, including two commonly reported genera of Zoogloea and Dechloromonas, three genera not frequently reported (i.e., Prosthecobacter, Caldilinea and Tricoccus) and three genera not well described so far (i.e., Gp4 and Gp6 in Acidobacteria and Subdivision3 genera incertae sedis of Verrucomicrobia). Pyrosequencing analyses of multiple AS samples in this study also revealed the minority populations that are hard to be explored by traditional molecular methods and showed that a large proportion of sequences could not be assigned to taxonomic affiliations even at the phylum/class levels. PMID:22170428

  4. Effects of Amended Sewage Sludge Application on Yield and Heavy Metal Uptake of Barley: A Case Study of Ahvaz Sewage Treatment Plant

    Directory of Open Access Journals (Sweden)

    Mostafa Chorom

    2007-06-01

    Full Text Available One aspect of sewage sludge application as an organic fertilizer on agricultural farms is environmental pollution concerns such as heavy metals uptake by plants. The aim of this study was to investigate the influence of amended sewage sludge application on yield and heavy metal uptake of Barley. This study was carried out over a period of barley growth with two treatments of sewage sludge (50 and 100 ton/ha and control treatment with four replicates arranged in a randomized complete block design. Plant samples were taken at three intervals (50, 90, and 180 days after sowing. The samples were prepared for measuring nutrients and heavy metals in stem, leaf, straw, and grain. Results of plant analysis showed that application of sewage sludge increased nitrogen, phosphorous, potassium and cadmium in vegetative parts compared to control. Grain analysis showed that application of sewage sludge significantly increased nitrogen, phosphorous, potassium, iron, and zinc. Grass yield significantly increased in the plot treated with 100 ton/ha sewage sludge. Grain yield in the two treatments significantly increased. The results revealed that the sewage sludge increased heavy metals uptake by plants but still below standard levels. It is, therefore, necessary to use the quantities of the elements introduced into soil and absorbed by plants in order to determine the toxicity level for each metal taking into account factors such as plant and soil types as well as environmental conditions. This information can then be used to determine sludge application quantities in each case. Meanwhile, sludge application may only be recommended for irrigated crops receiving adequate irrigation water due to its salinity. Moreover, it cannot be recommended for irrigated crops directly consumed by man.

  5. Composting of sewage sludge with solid fraction of digested pulp from agricultural biogas plant

    OpenAIRE

    Czekała Wojciech; Dach Jacek; Przybył Jacek; Mazurwiekiwcz Jakub; Janczak Damian; Lewicki Andrzej; Smurzyńska Anna; Kozłowski Kamil

    2018-01-01

    Sewage sludge management is an important element of environmental protection. Composting and anaerobic digestion are the biological conversion methods for sewage sludge management. Mass and volume reduction is a result of a properly composted process. Solid fraction of digested pulp can be use as co-substrate, because it is good structural material. The aim of the study was to determine the possibility of composting sewage sludge with a solid fraction of digestate. The compost mix consisted o...

  6. Utilization potential evaluation of plant resources in the dry-hot valley of Jinsha River

    Science.gov (United States)

    Xi, Rong; Xu, Naizhong; Liu, Shengxiang; Ren, Tingyan

    2017-08-01

    Plant resources in the dry-hot valley of Jinsha River are endemic to a class of district. The article adopts the analytic hierarchy process method to evaluate the exploitation and utilization potential of plant resources of thirty typical plant resources on the basis of their characteristics in the dry-hot valley of Jinsha River, which provide scientific evidence for quantitative evaluation of regional plant resources, and we also suggest pathways offering protection and development.

  7. Composting rice straw with sewage sludge and compost effects on the soil-plant system.

    Science.gov (United States)

    Roca-Pérez, L; Martínez, C; Marcilla, P; Boluda, R

    2009-05-01

    Composting organic residue is an interesting alternative to recycling waste as the compost obtained may be used as organic fertilizer. This study aims to assess the composting process of rice straw and sewage sludge on a pilot-scale, to evaluate both the quality of the composts obtained and the effects of applying such compost on soil properties and plant development in pot experiments. Two piles, with shredded and non-shredded rice straw, were composted as static piles with passive aeration. Throughout the composting process, a number of parameters were determined, e.g. colour, temperature, moisture, pH, electrical conductivity, organic matter, C/N ratio, humification index, cation exchange capacity, chemical oxygen demand, and germination index. Moreover, sandy and clayey soils were amended with different doses of mature compost and strewed with barley in pot experiments. The results show that compost made from shredded rice straw reached the temperatures required to maximise product sanitisation, and that the parameters indicating compost maturity were all positive; however, the humification index and NH(4) content were more selective. Therefore, using compost-amended soils at a dose of 34 Mg ha(-1) for sandy soil, and of 11 Mg ha(-1) for clayey soil improves soil properties and the growth of Hordeum vulgare plants. Under there conditions, the only limiting factor of agronomic compost utilisation was the increased soil salinity.

  8. Variations in heavy metal accumulation, growth and yield of rice plants grown at different sewage sludge amendment rates.

    Science.gov (United States)

    Singh, R P; Agrawal, M

    2010-05-01

    Use of sewage sludge in agriculture is an alternative disposal technique for this waste. The present field study was conducted to assess the suitability of sewage sludge amendment in soil for rice (Oryza sativa L. cv. Pusa sugandha 3) by evaluating the heavy metal accumulation, growth, biomass and yield responses of plants grown at 0, 3, 4.5, 6, 9, 12 kgm(-2) sewage sludge amendment (SSA) rate. Sewage sludge amendment modified the physico-chemical properties of soil, thus increasing the availability of heavy metals in soil and consequently with higher accumulation in plant parts. Root length decreased, whereas shoot length, number of leaves, leaf area and total biomass increased significantly when grown under various SSA rates. Yield of rice increased by 60%, 111%, 125%, 134% and 137% at 3, 4.5, 6, 9 and 12 kgm(-2) SSA, respectively, as compared to those grown in unamended soil. Sewage sludge amendment rates above 4.5 kgm(-2) though increased the yield of rice, but caused risk of food chain contamination as concentrations of Ni and Cd in rice grains were found to be above the Indian safe limits (1.5 mgkg(-1)) of human consumption above 4.5 kgm(-2) SSA and of Pb (2.5 mgkg(-1)) above 6 kgm(-2) SSA. Since aboveground parts of the rice also showed higher concentration than the permissible levels of Ni, Cd and Pb at 4.5 kgm(-2) SSA rate, it cannot be used as fodder. The rice husk may be used as bioresource for energy production. Efforts should be made to treat the effluents from small scale industries before discharge into the sewerage system. Copyright 2010 Elsevier Inc. All rights reserved.

  9. Comparative effects of partial rootzone drying and deficit irrigation on growth and physiology of tomato plants

    Directory of Open Access Journals (Sweden)

    Savić Slađana

    2009-01-01

    Full Text Available The effects of partial rootzone drying (PRD, deficit irrigation (DI, and full irrigation (FI on tomato physiology were investigated. In PRD and DI plants, leaf water potential values and stomatal conductance were significantly lower, while xylem ABA concentration was greater compared to FI plants. Photosynthesis was similar for all treatments. Water use efficiency was improved by PRD and DI, which reduced fruit dry weight, but had no effect on dry weight of leaves and stems.

  10. Measurement campaign on a solar sewage-sludge drying installation in Bilten, Switzerland; Messkampagne fuer eine solare Klaerschlammtrocknungsanlage in Bilten GL

    Energy Technology Data Exchange (ETDEWEB)

    Fischli, O. [Energieprojekte Fischli, Naefels, (Switzerland); Zweifel, H. R. [HSW Hochschule, Waedenswil (Switzerland)

    2004-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results obtained from a measurement campaign carried out at the Glarnerland wastewater treatment plant in Switzerland. The study established the input/output ratio of the installation and its overall energy demands. The plant's performance was monitored over a period of three years. Apart from the analysis of the plant's economics, the paper provides suggestions on how to improve overall performance and reduce energy costs. It was shown that the cost of final treatment of the sewage sludge was drastically reduced and that the plant can be run economically. Details on the costs and the advantages and disadvantages of the treatment process are presented and discussed.

  11. Composting plant of sewage sludges in Calles, Valencia (Spain); Planta de compostaje de fangos en la localidad de Calles (Valencia)

    Energy Technology Data Exchange (ETDEWEB)

    Morenilla Martinez, J. J.; Bernacer Bonora, I.; Jimenez Sanchez, J.; Zorrilla Soriano, F.; Manuelcandela, V.

    2000-07-01

    This article explains the operation of the composting plant of muds of residual waters in the location of Calles, in Valencia. Through the composting, the sludge is transformed in wet material. This process is developed by aerobic thermopile fermentation of the organic fraction of the muds. The composting is a biological process aerobic and thermopile by decomposition of organic waste in solid phase and in controlled conditions. (Author)

  12. Enhanced nitrogen removal in the combined activated sludge-biofilter system of the Southpest Wastewater Treatment Plant.

    Science.gov (United States)

    Jobbágy, A; Tardy, G M; Literáthy, B

    2004-01-01

    In 1999 the existing activated sludge unit of the Southpest Wastewater Treatment Plant was supplemented by a two-stage biofilter system aiming for nitrification and post-denitrification. In this arrangement excess biomass of the filters is wasted through the activated sludge unit, facilitating backseeding, and recirculation of the nitrate-rich effluent of the N-filter serves for decreasing the methanol demand of the DN-filter and for saving aeration energy at the same time. The paper reports on the development of an ASM1-based mathematical model that proved to be adequate for describing the interactions in the combined system and was used to compare the efficiency of different treatment options. Full-scale results verified that backseeding may considerably improve performance. However, nitrification ability of the activated sludge unit depends on the treatment temperature and, if unexpected, can be limited by insufficient oxygen supply. The upgrading possibilities outlined may serve as a new perspective for implementation of combined activated sludge-biofilter systems.

  13. Filamentous fungi in Indah Water Konsortium (IWK) sewage treatment plant for biological treatment of domestic wastewater sludge.

    Science.gov (United States)

    Fakhrul-Razi, A; Alam, M Zahangir; Idris, Azni; Abd-Aziz, Suraini; Molla, Abul H

    2002-03-01

    A study was carried out to isolate and identify filamentous fungi for the treatment of domestic wastewater sludge by enhancing biodegradability, settleability and dewaterability of treated sludge using liquid state bioconversion process. A total of 70 strains of filamentous fungi were isolated from three different sources (wastewater, sewage sludge and leachate) of IWK's (Indah Water Konsortium) sewage treatment plant, Malaysia. The isolated strains were purified by conventional techniques and identified by microscopic examination. The strains isolated belonged to the genera of Penicillium, Aspergillus, Trichoderma, Spicaria and Hyaloflorae The distribution of observed isolated fungi were 41% in sewage sludge followed by 39% in wastewater and 20% in leachate. The predominant fungus was Penicillium (39 strains). The second and third most common isolates were Aspergillus (14 strains) and Trichoderma (12 strains). The other isolates were Spicaria (3 strains) and Hyaloflorae (2 strains). Three strains (WWZP1003, LZP3001, LZP3005) of Penicillium (P. corylophilum, P. waksmanii, and P. citrinum respectively), 2 strains (WWZA1006 and SS2017) of Aspergillus (A. terrues and A. flavus respectively) and one strain (SSZT2008) of Trichoderma (T. harzianum) were tentatively identified up to species level and finally verified by CABI Bioscience Identification Services, UK.

  14. Monitoring of total metal concentration in sludge samples: Case study for the mechanical–biological wastewater treatment plant in Velika Gorica, Croatia

    International Nuclear Information System (INIS)

    Filipović, Josip; Grčić, Ivana; Bermanec, Vladimir; Kniewald, Goran

    2013-01-01

    In this paper, monitoring of total metal concentration in sludge samples from wastewater treatment process is elaborated. The presented results summarize the analyses of sludge samples in a period from 2008 to 2012. Possible sources of pollutions are given. Primarily, waste solid samples were collected from different pretreatment steps: (A) coarse grid, (B) fine grid and (C) aerated sand grease grid. Samples of A and B followed a repeatable pattern in 2008 and 2010. According to the results from 2008, samples of C contained measurable concentration of the following metals (mg/kg dry matter): Zn (21), Ni (1.05) and Ba (14.9). Several types of sludge samples were analyzed: fresh raw sludge (PS; 6–12 hour old), the sludge from the digester for anaerobic sludge treatment (DS; 48–72 hour old), samples from lagoons where the sludge is temporarily deposited (DOS and DOSold; 30–120 days) and sludge samples from agricultural areas (AA; aged over 180 days). Additionally, samples of dehydrated sludge (DEHS and DEHSold; 90–180 days) were collected upon construction of equipment for sludge dehydration in 2011. An analysis of total metal concentrations for Cu, Zn, Cr, Pb, Ni, Hg, Cd, Ba, As, Se, Sb, Co, Mo, Fe and Mn was performed by flame atomic absorption spectrometry (FAAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). The most recent results (year 2011) indicated a high concentration of heavy metals in PS samples, exceeding the MCLs (mg/kg dry matter): Cu (2122), Zn (5945), Hg (13.67) and Cd (6.29). In 2012 (until July), only a concentration of Cu exceeded MCL (928.75 and 1230.5 in DS and DEHS, respectively). A composition of sludge was variable through time, offering the limited possibility for future prediction. The sludge is being considered as a hazardous waste and a subject of discussion regarding disposal. - Highlights: ► Summarized 5-year monitoring data for heavy metals in sludge ► Partially determined sources of pollution by

  15. Agronomical use of sewage sludge from urban waste water treatment plant

    International Nuclear Information System (INIS)

    Motta, S.

    2009-01-01

    The Urban Waste Water Treatment Directive (91/271/EEC) aims to encourage the use of sludge whenever appropriate; the sewage sludge is a product of wastewater treatment which could find a reutilisation in the agricultural field. The necessity to find a solution to the sewage and biomass disposal has lead to the development of techniques based on natural reuse of agricultural soils. (Author)

  16. Effects of an exotic plant invasion on native understory plants in a tropical dry forest.

    Science.gov (United States)

    Prasad, Ayesha E

    2010-06-01

    The dry forests of southern India, which are endangered tropical ecosystems and among the world's most important tiger (Panthera tigris) habitats, are extensively invaded by exotic plants. Yet, experimental studies exploring the impacts of these invasions on native plants in these forests are scarce. Consequently, little is known about associated implications for the long-term conservation of tigers and other biodiversity in these habitats. I studied the impacts of the exotic plant Lantana camara on understory vegetation in a dry-forest tiger habitat in southern India. I compared the richness, composition, and abundance of tree seedlings, herbs, and shrubs and the abundance of grass among plots in which Lantana was cleared or left standing. These plots were distributed across two blocks-livestock free and livestock grazed. Removal of Lantana had an immediate positive effect on herb-shrub richness in the livestock-free block, but had no effect on that of tree seedlings in either livestock block. Tree-seedling and herb-shrub composition differed significantly between Lantana treatment and livestock block, and Lantana removal significantly decreased survival of tree seedlings. Nevertheless, the absence of trees, in any stage between seedling and adult, indicates that Lantana may stall tree regeneration. Lantana removal decreased the abundance of all understory strata, probably because forage plants beneath Lantana are less accessible to herbivores, and plants in Lantana-free open plots experienced greater herbivory. Reduced access to forage in invaded habitats could negatively affect ungulate populations and ultimately compromise the ability of these forests to sustain prey-dependent large carnivores. Additional research focused on understanding and mitigating threats posed by exotic plants may be crucial to the long-term protection of these forests as viable tiger habitats.

  17. Quality of plant-based food materials and its prediction during intermittent drying.

    Science.gov (United States)

    Duc Pham, Nghia; Khan, Md Imran H; Joardder, M U H; Rahman, M M; Mahiuddin, Md; Abesinghe, A M Nishani; Karim, M A

    2017-11-30

    In most drying processes, several physical, chemical and nutritional modifications take place in food products. Innovative drying techniques such as intermittent drying can enhance the quality of dehydrated products effectively and efficiently. Intermittent drying is a technique where drying conditions are changed through varying the drying air temperature, humidity, velocity, pressure, or even mode of heat input. This drying technique has been successfully applied to overcome the problems of conventional drying systems such as longer time consumption, case hardening, lower energy efficiency and poor-quality attributes. However, as the effect of intermittent drying on food quality is not yet well understood, a comprehensive study of quality change during intermittent drying is crucial. The main aim of this paper is to present a thorough review of the potential effect of intermittent drying methods on physical, chemical, nutritional, and stability characteristics of plant-based food material. It is found that application of intermittency using different drying systems has a significant effect on product quality and its stability. In addition, a comprehensive review on existing models of physio/biochemical kinetics for food drying is presented. Finally, the paper is concluded with the discussion of the current challenges and future directions of intermittent drying for producing high-quality dried food products.

  18. Updated activated sludge model number 1 parameter values for improved prediction of nitrogen removal in activated sludge processes: validation at 13 full-scale plants.

    Science.gov (United States)

    Choubert, Jean-Marc; Stricker, Anne-Emmanuelle; Marquot, Aurélien; Racault, Yvan; Gillot, Sylvie; Héduit, Alain

    2009-01-01

    The Activated Sludge Model number 1 (ASM1) is the main model used in simulation projects focusing on nitrogen removal. Recent laboratory-scale studies have found that the default values given 20 years ago for the decay rate of nitrifiers and for the heterotrophic biomass yield in anoxic conditions were inadequate. To verify the relevance of the revised parameter values at full scale, a series of simulations were carried out with ASM1 using the original and updated set of parameters at 20 degrees C and 10 degrees C. The simulation results were compared with data collected at 13 full-scale nitrifying-denitrifying municipal treatment plants. This work shows that simulations using the original ASM1 default parameters tend to overpredict the nitrification rate and underpredict the denitrification rate. The updated set of parameters allows more realistic predictions over a wide range of operating conditions.

  19. Development of an efficient process for the treatment of residual sludge discharged from an anaerobic digester in a sewage treatment plant.

    Science.gov (United States)

    Abe, Naoki; Tang, Yue-Qin; Iwamura, Makoto; Ohta, Hiroto; Morimura, Shigeru; Kida, Kenji

    2011-09-01

    In order to reduce the discharge of residual sludge from an anaerobic digester, pre-treatment methods including low-pressure wet-oxidation, Fenton oxidation, alkali treatment, ozone oxidation, mechanical destruction and enzymatic treatment were evaluated and compared. VSS removal efficiencies of greater than 50% were achieved in cases of low-pressure wet-oxidation, Fenton oxidation and alkali treatment. Residual sludge from an anaerobic digester was pre-treated and subjected to thermophilic anaerobic digestion. As a result, the process of low-pressure wet-oxidation followed by anaerobic digestion achieved the highest VSS removal efficiency of 83%. The total efficiency of VSS removal of sewage sludge consisting of primary and surplus sludge would be approximately 92%, assuming that the VSS removal efficiency of sewage sludge is 50% in the anaerobic digester of the sewage treatment plant. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Sewage sludge disinfection by irradiation (ENEA-ACEA collaboration)

    International Nuclear Information System (INIS)

    Baraldi, D.

    1997-01-01

    The Municipal Association for Electricity and Water (ACEA) of Rome and the Lazio Regional Administration are implementing a programme of intervention aimed at protecting the water quality of the hydrogeological basin of Lake Bracciano. With support from ENEA, a pilot plant is being constructed for sewage-sludge direction by irradiation with accelerated electrons, in order to use the sludge as a fertilizer for agriculture, as is practised abroad mainly in Germany and the United States. The work to be carried out within the ENEA-ACEA agreement includes: sludge digestion, drying, and sterilization by irradiation. Results achieved so far, including preliminary analyses of irradiated sludge, are presented. The irradiation plant and processes involved are also described. (author)

  1. Minimização da produção de lodo no tratamento de águas de abastecimento mediante uso do cloreto de polialumínio e sua disposição em estações de tratamento de esgotos Minimization of water treatment plant sludge production with polyaluminium chloride application and its disposal in wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Sidney Seckler Ferreira Filho

    2009-09-01

    Full Text Available Uma das possibilidades para a redução da produção de lodo em estações de tratamento de água (ETAs é o uso do cloreto de polialumínio (CPA como coagulante, que pode ser aplicado de forma isolada ou em conjunto com sais de ferro. Este trabalho objetivou estudar o uso do CPA no que diz respeito à produção de lodo, bem como avaliar o impacto do lançamento de lodos de ETAs em estações de tratamento de esgoto (ETEs do tipo lodos ativados convencional. Observou-se que a produção de lodo do CPA apresentou valores próximos em comparação ao sulfato de alumínio, em torno de 4,75 mg de massa seca para cada 1 mg de Al, e o seu eventual lançamento para posterior processamento em ETEs deverá alterar a qualidade físico-química do lodo desidratado, sendo esta função do tipo e dosagem de coagulante e suas impurezas.One possible strategy to reduce sludge production in water treatment plant (WTP is the application of polyaluminium chloride (PAC as the sole coagulant or together with iron salts. The purpose of this paper was to investigate PAC usage with regard to sludge production as well as to evaluate impacts of discharging WTP sludge in activated sludge wastewater treatment plants (WWTPs. It was observed that PAC-based sludge production presented values close to aluminum sulfate-based sludge production, which was around 4.75 mg of dry solids per mg of Al. Furthermore, eventual discharge of PAC-based sludge in a WWTP should change the physical and chemical quality of the dry sludge, which is a function of coagulant type, coagulant dosage and of the impurities present in the coagulan's formulation.

  2. Sludge minimization technologies - an overview

    Energy Technology Data Exchange (ETDEWEB)

    Oedegaard, Hallvard

    2003-07-01

    The management of wastewater sludge from wastewater treatment plants represents one of the major challenges in wastewater treatment today. The cost of the sludge treatment amounts to more that the cost of the liquid in many cases. Therefore the focus on and interest in sludge minimization is steadily increasing. In the paper an overview is given for sludge minimization (sludge mass reduction) options. It is demonstrated that sludge minimization may be a result of reduced production of sludge and/or disintegration processes that may take place both in the wastewater treatment stage and in the sludge stage. Various sludge disintegration technologies for sludge minimization are discussed, including mechanical methods (focusing on stirred ball-mill, high-pressure homogenizer, ultrasonic disintegrator), chemical methods (focusing on the use of ozone), physical methods (focusing on thermal and thermal/chemical hydrolysis) and biological methods (focusing on enzymatic processes). (author)

  3. Application of biochar from sewage sludge to plant cultivation: Influence of pyrolysis temperature and biochar-to-soil ratio on yield and heavy metal accumulation.

    Science.gov (United States)

    Song, X D; Xue, X Y; Chen, D Z; He, P J; Dai, X H

    2014-08-01

    Applying biochar products from sewage sludge (SS) pyrolysis as soil amendment for plant cultivation was investigated in this study with special attention paid to heavy metal accumulation in the plants when pyrolysis temperature and biochar-to-soil mass ratio (C:S) were changed. Biochar obtained at four different temperatures were adopted as soil amendment for Allium sativum L. garlic plant cultivation. Experimental results revealed that biochars were rich in nutrient contents and they improved garlic yields. Although contents of heavy metals including As, Zn, Pb, Ni, Cd, Cr and Cu, etc. were elevated in the biochars compared to local soil, they fell within the acceptable limits for land application and SS is a suitable biochar resource, especially biochar produced at 450°C had rich micropores, relatively stable functional groups in structure and rugged surface to contact well with soil, conducive to its usage as a biochar. The garlic grew faster when planted in the biochar-amended soil and had higher final dry matter yields than those planted in the reference soil, especially biochar produced at 450°C corresponding to the highest final yields. The C:S ratio related to the highest garlic yields changed when the pyrolysis temperature was changed and this ratio was 1:4 for the biochar produced at 450°C. General heavy metal accumulation in the garlic occurred only for the most enriched Zn and Cu, and mainly in the roots & bulbs; in addition this bioaccumulation was increasing as leaching from biochar increased but not increasing with C:S ratio. The garlic planted in soil amended with biochar of 450°C contained the lowest level of heavy metals compared to other biochars. Those results indicated that heavy metal accumulation in plants can be inhibited through proper pyrolysis temperature choice and prevention of heavy metal leaching from the SS biochar. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. A Grey-Box Model for Spray Drying Plants

    DEFF Research Database (Denmark)

    Petersen, Lars Norbert; Poulsen, Niels Kjølstad; Niemann, Hans Henrik

    2013-01-01

    Multi-stage spray drying is an important and widely used unit operation in the production of food powders. In this paper we develop and present a dynamic model of the complete drying process in a multi-stage spray dryer. The dryer is divided into three stages: The spray stage and two fluid bed...

  5. Potential of recycling gamma-irradiated sewage sludge for use as a fertilizer: a study on chickpea (Cicer arietinum)

    International Nuclear Information System (INIS)

    Pandya, G.A.; Sachidanand, S.; Modi, V.V.

    1989-01-01

    The effects of gamma-irradiated sludge on the growth and yield of chickpea (Cicer arietinum) in pot cultures have been studied. Compared to plants grown only in soil, root length, fresh weight and dry weight of plants grown in soil supplemented with unirradiated sludge were found to be significantly reduced. This inhibition in growth was found to be nullified when plants were grown in soil supplemented with gamma-irradiated sludge, suggesting that gamma radiation induced inactivation of toxic substance(s) in sludge. The protein content of plants grown in soil supplemented with irradiated sludge was also found to be significantly increased compared to those grown with unirradiated or no sludge, after 45 days. There was no significant effect of gamma irradiated sludge on shoot length, total soluble sugars, starch content and yield of chickpea plants. The results obtained suggest that the sludge tested, and obtained from the digester of a conventional domestic sewage treatment plant, is inhibitory to several growth parameters. Gamma irradiation of sewage resulted in removal of this inhibition. This suggests a possibility of beneficial and safe recycling of gamma-irradiated sludge for agricultural uses. (author)

  6. Prediction analysis of effluent removal in a septic sludge treatment plant: a biomimetics engineering approach.

    Science.gov (United States)

    Chun, Ting Sie; Malek, M A; Ismail, Amelia Ritahani

    2014-09-20

    Effluent discharge from septic tanks is affecting the environment in developing countries. The most challenging issue facing these countries is the cost of inadequate sanitation, which includes significant economic, social, and environmental burdens. Although most sanitation facilities are evaluated based on their immediate costs and benefits, their long-term performance should also be investigated. In this study, effluent quality-namely, the biological oxygen demand (BOD), chemical oxygen demand (COD), and total suspended solid (TSS)-was assessed using a biomimetics engineering approach. A novel immune network algorithm (INA) approach was applied to a septic sludge treatment plant (SSTP) for effluent-removal predictive modelling. The Matang SSTP in the city of Kuching, Sarawak, on the island of Borneo, was selected as a case study. Monthly effluent discharges from 2007 to 2011 were used for training, validating, and testing purposes using MATLAB 7.10. The results showed that the BOD effluent-discharge prediction was less than 50% of the specified standard after the 97(th) month of operation. The COD and TSS effluent removals were simulated at the 85(th) and the 121(st) months, respectively. The study proved that the proposed INA-based SSTP model could be used to achieve an effective SSTP assessment and management technique.

  7. Chemical and thermal properties of VIP latrine sludge

    African Journals Online (AJOL)

    2015-07-04

    Jul 4, 2015 ... This study investigated the chemical and thermal properties of faecal sludge from 10 dry VIP latrines in Bester's Camp in the eThekwini Municipality, Durban, ... emptying and treatment equipment. A manual sorting of the pit .... (LaDePa) plant (Harrison and Wilson, 2012). Figure 3 illustrates the depths of the ...

  8. The compost with the OFMSW as a solution for the sludges from the wastewater purification plants; Compostaje con FORSU como una solucion para los fangos de depuradora

    Energy Technology Data Exchange (ETDEWEB)

    Chica Perez, A.; Diaz Rubio, M. M.; Mohedo Gaton, J. J.; Martin Martin, A. [Universidad de Cardoba (Spain); Revilla Alvarez, J. R.

    2001-07-01

    The correct management of the sludges coming from the municipal wastewater purification plants (mwpp) is an unsolved problem in many cases and its volume is quickly increasing. As a solution for its treatment and disposal the composting process of the sludges combined with the organic fraction of municipal solid wastes (OFMSW) selectively collected is proposed in this work. A suitable compost for agricultural use is obtained. Using respirometer methods better than using other analytical parameters can monitor the stabilisation process of the mixture of sludges from MWPP and OFMSW. The measurement of the maximum oxygen intake specific rate indicates an appropriate stabilisation of the mixture after third treatment month. (Author) 32 refs.

  9. Non-destructive quantification of water gradient in sludge composting with Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    Duval, F.P.; Quellec, S.; Tremier, A.; Druilhe, C.; Mariette, F.

    2010-01-01

    Sludge from a slaughter-house wastewater plant, and mixtures of bulking agent (crushed wood pallet) and sludge were studied by Nuclear Magnetic Resonance (NMR). The NMR spin-spin relaxation (T 2 ) and spin-lattice relaxation (T 1 ) signals for sludge, wet crushed wood pallet and mixtures of sludge and bulking agent were decomposed into three relaxation time components. Each relaxation time component was explained by a non-homogeneous water distribution on a microscopic length scale and by the porosity of the material. For all samples, the T 2 relaxation time value of each component was directly related to the dry matter content. The addition of wet crushed wood to sludge induced a decrease in the relaxation time, explained by water transfer between the sludge and the wood. Magnetic Resonance Imaging (MRI) and respirometric measurements were performed on sludge and wood mixtures. MR images of the mixtures were successfully obtained at different biodegradation states. Based on specific NMR measurements in an identified area located in the MRI cells, the results showed that grey levels of MR images reflected dry matter content. This preliminary study showed that MRI would be a powerful tool to measure water distribution in sludge and bulking agent mixtures and highlights the potential of this technique to increase the understanding of sludge composting.

  10. Applying Sewage Sludge to Eucalyptus grandis Plantations: Effects on Biomass Production and Nutrient Cycling through Litterfall

    International Nuclear Information System (INIS)

    Da Silva, P.H.M.; Poggiani, F.; Laclau, J.P.

    2011-01-01

    In most Brazilian cities sewage sludge is dumped into sanitary landfills, even though its use in forest plantations as a fertilizer and soil conditioner might be an interesting option. Sewage sludge applications might reduce the amounts of mineral fertilizers needed to sustain the productivity on infertile tropical soils. However, sewage sludge must be applied with care to crops to avoid soil and water pollution. The aim of our study was to assess the effects of dry and wet sewage sludges on the growth and nutrient cycling of Eucalyptus grandis plantations established on the most common soil type for Brazilian eucalypt plantations. Biomass production and nutrient cycling were studied over a 36-month period in a complete randomized block design. Four experimental treatments were compared: wet sewage sludge, dry sludge, mineral fertilizer, and no fertilizer applications. The two types of sludges as well as mineral fertilizer increased significantly the biomass of Eucalyptus trees. Wood biomass productions 36 months after planting were similar in the sewage sludge and mineral fertilization treatments (about 80 tons ha - '1) and 86 % higher than in the control treatment. Sewage sludge application also affected positively leaf litter production and significantly increased nutrient transfer among the components of the ecosystem.

  11. Applying Sewage Sludge to Eucalyptus grandis Plantations: Effects on Biomass Production and Nutrient Cycling through Litterfall

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Müller da Silva

    2011-01-01

    Full Text Available In most Brazilian cities sewage sludge is dumped into sanitary landfills, even though its use in forest plantations as a fertilizer and soil conditioner might be an interesting option. Sewage sludge applications might reduce the amounts of mineral fertilizers needed to sustain the productivity on infertile tropical soils. However, sewage sludge must be applied with care to crops to avoid soil and water pollution. The aim of our study was to assess the effects of dry and wet sewage sludges on the growth and nutrient cycling of Eucalyptus grandis plantations established on the most common soil type for Brazilian eucalypt plantations. Biomass production and nutrient cycling were studied over a 36-month period in a complete randomized block design. Four experimental treatments were compared: wet sewage sludge, dry sludge, mineral fertilizer, and no fertilizer applications. The two types of sludges as well as mineral fertilizer increased significantly the biomass of Eucalyptus trees. Wood biomass productions 36 months after planting were similar in the sewage sludge and mineral fertilization treatments (about 80 tons ha−1 and 86% higher than in the control treatment. Sewage sludge application also affected positively leaf litter production and significantly increased nutrient transfer among the components of the ecosystem.

  12. Two-phase anaerobic digestion of partially acidified sewage sludge: a pilot plant study for safe sludge disposal in developing countries.

    Science.gov (United States)

    Passio, Luca; Rizzoa, Luigi; Fuchs, Stephan

    2012-09-01

    The unsafe disposal of wastewater and sludge in different areas of developing countries results in significant environmental pollution, particularly for groundwater, thus increasing the risk of waterborne diseases spreading. In this work, a two-phase anaerobic digestion process for post-treatment of partially acidified sewage sludge was investigated to evaluate its feasibility as a safe sludge disposal system. Pilot tests showed that an effective sludge stabilization can be achieved (total volatile solids content sludge without restrictions is possible according to US Environmental Protection Agency criteria for safe sludge disposal. A biogas production as high as 390 L/d with a 60% methane content by volume was achieved, showing that energy production from biogas may be achieved as well.

  13. Chemical and biochemical characterization of sewage sludges from wastes treatment plant in Burgos (Spain); Caracterizacion quimica y bioqumica de lodos de depuradora de aguas residuales de Burgos

    Energy Technology Data Exchange (ETDEWEB)

    Navarro Gonzalez, M.; Saiz Orcajo, R. M.; Puente Miguel, G.; Carcedo Gonzalez, S. [Universidad de Burgos. Burgos (Spain)

    1998-12-31

    A study was carried out in order to evaluate the degree of heavy metals and potential of phosphohidrolitic, cellulotic and amidasic capacity of sewage sludges from Burgos wastewater treatment plant. The aim of the present paper is to look at the possibilities of using sewage sludge as an element in soil regeneration and maintaining green areas and the conditions governing its use on agricultural land. (Author) 15 refs.

  14. Anaerobic digestion of whole stillage from dry-grind corn ethanol plant under mesophilic and thermophilic conditions.

    Science.gov (United States)

    Eskicioglu, Cigdem; Kennedy, Kevin J; Marin, Juan; Strehler, Benjamin

    2011-01-01

    Anaerobic digestion of whole stillage from a dry-grind corn-based ethanol plant was evaluated by batch and continuous-flow digesters under thermophilic and mesophilic conditions. At whole corn stillage concentrations of 6348 to 50,786 mg total chemical oxygen demand (TCOD)/L, at standard temperature (0 °C) and pressure (1 atm), preliminary biochemical methane potential assays produced 88±8 L (49±5 L CH4) and 96±19 L (65±14 L CH4) biogas per L stillage from mesophilic and thermophilic digesters, respectively. Continuous-flow studies for the full-strength stillage (TCOD=254 g/L) at organic loadings of 4.25, 6.30 and 9.05 g TCOD/L days indicated unstable performance for the thermophilic digester. Among the sludge retention times (SRTs) of 60, 45 and 30 days tested, the mesophilic digestion was successful only at 60 days-SRT which does not represent a practical operation time for a large scale bioethanol plant. Future laboratory studies will focus on different reactor configurations to reduce the SRT needed in the digesters. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Composting of sewage sludge with solid fraction of digested pulp from agricultural biogas plant

    Science.gov (United States)

    Czekała, Wojciech; Dach, Jacek; Przybył, Jacek; Mazurwiekiwcz, Jakub; Janczak, Damian; Lewicki, Andrzej; Smurzyńska, Anna; Kozłowski, Kamil

    2018-02-01

    Sewage sludge management is an important element of environmental protection. Composting and anaerobic digestion are the biological conversion methods for sewage sludge management. Mass and volume reduction is a result of a properly composted process. Solid fraction of digested pulp can be use as co-substrate, because it is good structural material. The aim of the study was to determine the possibility of composting sewage sludge with a solid fraction of digestate. The compost mix consisted of 25 kilograms of sewage sludge and 20 kilograms solid fraction of digestate in fresh mass. The experiment was carried out in laboratory conditions. Bioreactors of 165 dm3 volume were used. The experiment included two stages. Stage I took place in bioreactors and lasted until the cooling phase of the compost was complete. Stage II included compost maturation for a period of eight months (to 287 day of composting). The reduction of mass obtained at the end of Stage I amounted 30.2%. At the end of Stage II, it was 86.7% relative to the initial weight of the compost. The maximum value of temperature was 75.1°C. Studies have shown that sludge with a solid fraction of digestate can be a suitable substrate for composting with sewage sludge.

  16. Composting of sewage sludge with solid fraction of digested pulp from agricultural biogas plant

    Directory of Open Access Journals (Sweden)

    Czekała Wojciech

    2018-01-01

    Full Text Available Sewage sludge management is an important element of environmental protection. Composting and anaerobic digestion are the biological conversion methods for sewage sludge management. Mass and volume reduction is a result of a properly composted process. Solid fraction of digested pulp can be use as co-substrate, because it is good structural material. The aim of the study was to determine the possibility of composting sewage sludge with a solid fraction of digestate. The compost mix consisted of 25 kilograms of sewage sludge and 20 kilograms solid fraction of digestate in fresh mass. The experiment was carried out in laboratory conditions. Bioreactors of 165 dm3 volume were used. The experiment included two stages. Stage I took place in bioreactors and lasted until the cooling phase of the compost was complete. Stage II included compost maturation for a period of eight months (to 287 day of composting. The reduction of mass obtained at the end of Stage I amounted 30.2%. At the end of Stage II, it was 86.7% relative to the initial weight of the compost. The maximum value of temperature was 75.1°C. Studies have shown that sludge with a solid fraction of digestate can be a suitable substrate for composting with sewage sludge.

  17. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlândia-MG, Brazil

    International Nuclear Information System (INIS)

    Oliveira Silva, Jader de; Filho, Guimes Rodrigues; Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Júlia Graciele; Vieira da Silva, Cleuzilene; Alves Cerqueira, Daniel

    2012-01-01

    Highlights: ► In this study, the sludge was characterized by thermal analyses and FTIR. ► The superior calorific value of the sludge was 16.2 MJ kg −1 . ► The sludge showed a significant biodegradable portion of 65%. ► The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlândia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg −1 was found, which is within the range of values reported in the literature.

  18. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlandia-MG, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Silva, Jader de [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Departamento Municipal de Agua e Esgoto de Uberlandia (DMAE) (Brazil); Filho, Guimes Rodrigues, E-mail: guimes@ufu.br [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Julia Graciele [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Vieira da Silva, Cleuzilene [Faculdade de Engenharia Quimica da Universidade Federal de Uberlandia (Brazil); Alves Cerqueira, Daniel [Instituto de Ciencias Ambientais e Desenvolvimento Sustentavel da Universidade Federal da Bahia (Brazil)

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer In this study, the sludge was characterized by thermal analyses and FTIR. Black-Right-Pointing-Pointer The superior calorific value of the sludge was 16.2 MJ kg{sup -1}. Black-Right-Pointing-Pointer The sludge showed a significant biodegradable portion of 65%. Black-Right-Pointing-Pointer The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlandia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg{sup -1} was found, which is within the range of values reported in the literature.

  19. EFFECTS OF SEWAGE SLUDGE AND SEWAGE SLUDGE COMPOST AMENDMENT ON SOIL PROPERTIES AND Zea mays L. PLANTS (HEAVY METALS, QUALITY AND PRODUCTIVITY)

    OpenAIRE

    Rocío VACA

    2011-01-01

    The use of organic wastes in agriculture can improve the soil's productive capacity, and physical and chemical characteristics. This study evaluated the effects of sewage sludge, sewage sludge compost and inorganic fertilizer applications on nickel, copper and zinc contents in soil and corn grains (Zea mays L); maize productivity, and grain nutritional quality. Sewage sludge and sewage sludge compost at 18 Mg ha¿1 and a mineral fertilizer (N-P-K) with a formulation of 150-75-30 were applied. ...

  20. Sewage sludge as a biomass energy source

    OpenAIRE

    Pavel Kolat; Zdeněk Kadlec

    2013-01-01

    The major part of the dry matter content of sewage sludge consists of nontoxic organic compounds, in general a combination of primary sludge and secondary microbiological sludge. The sludge also contains a substantive amount of inorganic material and a small amount of toxic components. There are many sludge-management options in which production of energy is one of the key treatment steps. The most important options are anaerobic digestion, co-digestion, incineration in combination with energ...

  1. First discovery of acetone extract from cottonseed oil sludge as a novel antiviral agent against plant viruses.

    Directory of Open Access Journals (Sweden)

    Lei Zhao

    Full Text Available A novel acetone extract from cottonseed oil sludge was firstly discovered against plant viruses including Tobacco mosaic virus (TMV, Rice stripe virus (RSV and Southern rice black streaked dwarf virus (SRBSDV. Gossypol and β-sitosterol separated from the acetone extract were tested for their effects on anti-TMV and analysed by nuclear magnetic resonance (NMR assay. In vivo and field trials in different geographic distributions and different host varieties declared that this extract mixture was more efficient than the commercial agent Ningnanmycin with a broad spectrum of anti-plant-viruses activity. No phytotoxic activity was observed in the treated plants and environmental toxicology showed that this new acetone extract was environmentally friendly, indicating that this acetone extract has potential application in the control of plant virus in the future.

  2. First discovery of acetone extract from cottonseed oil sludge as a novel antiviral agent against plant viruses.

    Science.gov (United States)

    Zhao, Lei; Feng, Chaohong; Hou, Caiting; Hu, Lingyun; Wang, Qiaochun; Wu, Yunfeng

    2015-01-01

    A novel acetone extract from cottonseed oil sludge was firstly discovered against plant viruses including Tobacco mosaic virus (TMV), Rice stripe virus (RSV) and Southern rice black streaked dwarf virus (SRBSDV). Gossypol and β-sitosterol separated from the acetone extract were tested for their effects on anti-TMV and analysed by nuclear magnetic resonance (NMR) assay. In vivo and field trials in different geographic distributions and different host varieties declared that this extract mixture was more efficient than the commercial agent Ningnanmycin with a broad spectrum of anti-plant-viruses activity. No phytotoxic activity was observed in the treated plants and environmental toxicology showed that this new acetone extract was environmentally friendly, indicating that this acetone extract has potential application in the control of plant virus in the future.

  3. Potential values of some non-leguminous browse plants as dry ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-03

    May 3, 2010 ... plants as dry season feed for ruminants in Nigeria. D. O. Ogunbosoye* and O. J. Babayemi ... Inadequate feed supply is a major constraint to ruminant production during the dry season in the tropics. ... nutritional composition of some non leguminous multi- purpose trees by their chemical composition and in ...

  4. Simulation of co-incineration of sewage sludge with municipal solid waste in a grate furnace incinerator.

    Science.gov (United States)

    Lin, Hai; Ma, Xiaoqian

    2012-03-01

    Incineration is one of the most important methods in the resource recovery disposal of sewage sludge. The combustion characteristics of sewage sludge and an increasing number of municipal solid waste (MSW) incineration plants provide the possibility of co-incineration of sludge with MSW. Computational fluid dynamics (CFD) analysis was used to verify the feasibility of co-incineration of sludge with MSW, and predict the effect of co-incineration. In this study, wet sludge and semi-dried sludge were separately blended with MSW as mixed fuels, which were at a co-incineration ratios of 5 wt.% (wet basis, the same below), 10 wt.%, 15 wt.%, 20 wt.% and 25 wt.%. The result indicates that co-incineration of 10 wt.% wet sludge with MSW can ensure the furnace temperature, the residence time and other vital items in allowable level, while 20 wt.% of semi-dried sludge can reach the same standards. With lower moisture content and higher low heating value (LHV), semi-dried sludge can be more appropriate in co-incineration with MSW in a grate furnace incinerator. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Rhodococcus lactis sp. nov., an actinobacterium isolated from sludge of a dairy waste treatment plant.

    Science.gov (United States)

    Singh, Pradip Kumar; Kumari, Annu; Chawla, Niharika; Pinnaka, Anil Kumar; Korpole, Suresh

    2015-11-01

    A Gram-stain-positive, non-motile and aerobic bacterium, designated strain DW151BT, was isolated from a sludge sample of a dairy industry effluent treatment plant. 16S rRNA gene sequence analysis of strain DW151BT placed it within the genus Rhodococcus. It displayed significant similarity with recognized species of the genus: Rhodococcus pyridinivorans PDB9T (98.8 %), Rhodococcus gordoniae W 4937T (98.6 %), Rhodococcus rhodochrous DSM 43241T (98.5 %) and Rhodococcus artemisiae YIM 65754T (97.5 %). However, strain DW151BT differed from phylogenetically closely related species in various phenotypic properties. The cellular polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE) and phosphatidylinositol (PI) as major lipids, MK-8(H2) was the major menaquinone and meso-diaminopimelic acid was the cell-wall peptidoglycan. The fatty acid profile consisted of C16 : 0, C18 : 1cis9 and C16 : 1cis9 as main components. The presence of C16 : 0 and diphosphatidylglycerol as major fatty acid and polar lipid, respectively, was in accordance with chemotaxonomic markers of the genus Rhodococcus. The DNA G+C content of strain DW151BT was 69.9 mol%, a value within the limits reported for the members of this genus. Furthermore, strain DW151BT showed low similarity at the whole genome level in DNA-DNA hybridization experiments with phylogenetically closely related strains. Considering the low similarity at the genome level and differences in phenotypic properties, strain DW151BT is considered to represent a novel species of the genus Rhodococcus, for which the name Rhodococcus lactis sp. nov. is proposed. The type strain is DW151BT ( = MTCC 12279T = DSM 45625T).

  6. Intensifying drying process with creation of functional plant compositions

    OpenAIRE

    Zh. Petrova; Yu. Snezhkіn; K. Getmanyuk; N. Dmytrenko; M. Vorontsov

    2015-01-01

    Introduction. The process of drying agricultural raw products is associated with loss of bioactive substances by the products exposed to heat, light, oxygen, or рН medium. It is reasonable to enhance the table beet processing technology in order to achieve maximum betanin conservation at lower energy consumption. Materials and methods. Table beets, rhubarbs, lemons, and tomatoes were dried at temperature of 50 to 100 ºС, air speed of 1.5 to 3.5 m/s, heat c...

  7. Dry Ice Blast Decontamination to in-service equipment in Japanese PWR plant

    International Nuclear Information System (INIS)

    2016-01-01

    MHI had developed several mechanical decontamination methods. Mechanical decontamination is beneficial when it is applied to equipment whose surface is narrow. Especially in terms of secondary waste reduction, MHI started the study of application of Dry Ice Blast Decontamination to actual PWR plant. This paper provides an introduction to Dry Ice Blast Decontamination principle, its system and actual application result to PWR plant. (J.P.N.)

  8. Efeito da adição de lodo de curtume na fertilidade do solo, nodulação e rendimento de matéria seca do Caupi Effect of tannery sludge addition on soil fertility, nodulation and dry matter yield of Cowpea

    Directory of Open Access Journals (Sweden)

    Keyla Rafaelly Gramosa Teixeira

    2006-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito do lodo de curtume sobre a fertilidade do solo, a nodulação e rendimento de matéria seca do caupi. O estudo foi conduzido em casa-de-vegetação, utilizando-se lodo de curtume adicionado ao solo, sendo em seguida plantadas sementes de caupi inoculadas com Bradyrhizobium sp. Os dados foram coletados aos 35 e 49 dias após a emergência das plantas. O lodo de curtume elevou o pH e os teores de matéria orgânica, cálcio e sódio do solo. Além disso, houve aumento na salinidade do solo com a aplicação do resíduo. Por outro lado, houve um incremento no rendimento de matéria seca do caupi com a adição do lodo de curtume, embora, em altas doses, o resíduo tenha diminuído a nodulação do caupi pela estirpe de Bradyrhizobium sp inoculada.The aim of this paper was to evaluate the effect of tannery sludge addition on soil fertility, nodulation and dry matter yield by cowpea. The study was conducted in greenhouse using tannery sludge applied to soil, and cowpea seeds inoculated with Bradyrhizobium sp. Data were collected at 35 and 49 days after plant emergence. Tannery sludge increased soil pH and organic matter, calcium and sodium content. There was an increase in soil salinity with application of the residue. There was also an increase in the dry matter yield of cowpea with tannery sludge addition, however, in higher rates, the residue decreased the Bradyrhizobium sp nodulation.

  9. Nitrogen Removal in a Full-Scale Domestic Wastewater Treatment Plant with Activated Sludge and Trickling Filter

    Directory of Open Access Journals (Sweden)

    Davood Nourmohammadi

    2013-01-01

    Full Text Available During the last decade, more stringent effluent requirements concerning the nutrients effluent values have been imposed by legislation and social concern. In this study, efficiency of total nitrogen removal in activated sludge and trickling filter processes (AS/TF was investigated in Tehran North wastewater treatment plant. Biological system in this site was included, anoxic selector tank, aeration tank, final sedimentation, and trickling filter. A part of treated wastewater before chlorination was mixed with supernatant of dewatered sludge and fed to the trickling filter. Supernatant of dewatered sludge with high concentration of NH4-N was diluted by treated wastewater to provide complete nitrification in trickling filter Produced nitrate in trickling filter was arrived to the anoxic tank and converted to nitrogen gas by denitrification. According to the study result, low concentration of organic carbone and high concentration of NH4-N led to nitrification in TF, then nitrate denitrification to nitrogen gas occurred in selector area. NH4-N concentration decreased from 26.8 mg/L to 0.29 mg/L in TF, and NO3-N concentration increased from 8.8 mg/L to 27 mg/L in TF. Consequently, the total nitrogen decreased approximately to 50% in biological process. This efficiency has been observed in returned flow around 24% from final sedimentation into TF. It was concluded that, in comparison with biological nutrient removal processes, this process is very efficient and simple.

  10. Changes in micronutrients, dry weight and plant growth of soybean ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-03

    Jun 3, 2008 ... Salinity stress negatively affected soybean cultivars and the ... Key words: Soybean, Glycine max (L), salt stress, dry weight, micronutrient accumulation. ..... Iron, copper, zinc and manganese contents wheat and rice varieties under salt stress. Turk. J. Agric. Forest, 22: 227-233. Ashraf M, McNeilly T (1990).

  11. Changes of micronutrients, dry weight and plant development in ...

    African Journals Online (AJOL)

    This study was carried out to determine the effects of salt stress on the growth, dry weights and micronutrient contents of canola (Brassica napus L.) cultivars grown in greenhouse conditions. 12 canola cultivars (Marinca, Kosa, Spok, Semu DNK207 NA, Tower, Liraspa, Star, Tobin, Helios, Semu 209/81, Regent and Lirawell) ...

  12. Investigation of pre-drying lignite in an existing Greek power plant

    Directory of Open Access Journals (Sweden)

    Agraniotis Michalis

    2012-01-01

    Full Text Available The application of lignite pre-drying technologies in next generation of lignite power plants by utilizing low pressure steam as a drying medium instead of hot recirculated flue gas - combined with thermal utilization of the vaporized coal moisture - is expected to bring efficiency increase of 2-4 percentage points in future lignite power plants compared with today’s state of the art. The pre-drying concept is of particular importance in Greek boilers firing lignite with a high water and ash content. The combustion of Greek predried lignite has been investigated experimentally and via numerical simulations in our previous research. This study focuses on the potential integration of a lignite pre-drying system in an existing Greek power plant with dry lignite co-firing thermal share of up to 30%. The radiative and convective heat fluxes to the boiler and the overall boiler heat balance is calculated for reference and dry lignite co-firing conditions by an in-house calculation code. The overall plant’s thermal cycle is then simulated using commercial thermal cycle calculation software. The net plant efficiency is in this way determined for reference and dry coal co-firing conditions. According to the simulation results the integration of a pre-drying system and the implementation of dry lignite co-firing may bring an efficiency increase of about 1.5 percentage points in existing Greek boilers. It is therefore considered as an important measure towards improving plant efficiency and reducing specific CO2 emissions in existing plants.

  13. Feasibility Study on Manufacturing Lightweight Aggregates from Water Purification Sludge

    Science.gov (United States)

    Peng, Ching-Fang; Chen, How-Ji

    2018-02-01

    This study mainly discussed the feasibility of manufacturing lightweight aggregates from water purification sludge in Taiwan. They were analysed for the physical and chemical composition before the sintering test for lightweight aggregates in a laboratory. Then the physical and mechanical properties of the synthesized aggregates were assessed. The result showed that the chemical composition of sludge in the water purification plants was within the appropriate range for manufacturing lightweight aggregate as proposed in the literature. The sintering test demonstrated that the particle density of aggregates from the ten types of water purification sludge were mostly less than 1.8 g/cm3. In addition, the dry unit weight, the organic impurity, the ignition loss, and other characteristics of synthesized aggregates met the requirement of CNS standards, while its water absorption and crushing strength also fulfilled the general commercial specifications. Therefore, reclamation of water purification sludge for production of lightweight aggregate is indeed feasible.

  14. Sustainable measures for sewage sludge treatment - evaluating the effects on P reaction in soils and plant P uptake

    Science.gov (United States)

    Shenker, Moshe; Einhoren, Hana

    2016-04-01

    Wastewater treatment, whether for water reusing or for releasing into the environment, results in sewage sludge rich in organic matter and nutrients. If free of pathogens and pollutants, this waste material is a widely used as soil amendment and source of valuable nutrients for agronomic use. Nevertheless, its P/N ratio largely exceeds plant P/N demand. Limiting its application rates according to the P demand of crops will largely limit its application rates and its beneficial effect as a soil amendment and as a source for other nutrients. An alternative approach, in which P is stabilized before application, was evaluated in this study. Anaerobically digested fresh sewage sludge (FSS) was stabilized by aluminum sulfate, ferrous sulfate, and calcium oxide (CaO), as well as by composting with shredded woody yard-waste to produce Al-FSS, Fe-FSS, CaO-FSS, and FSS-compost, respectively. Defined organic-P sources (glucose-1-phosphate and inositol-hexa-phosphate) and a P fertilizer (KH2PO4) were included as well and a control with no P amendments was included as a reference. Each material was applied at a fixed P load of 50 mg kg-1 to each of three soils and P speciation and plants P uptake were tested along 112 days of incubation at moderate (near field capacity) water content. Tomato seedlings were used for the P uptake test. The large set of data was used to evaluate the effect of each treatment on P reactions and mechanisms of retention in the tested soils and to correlate various P indices to P availability for plants. Plant P uptake was highly correlated to Olsen-P as well as to water-soluble inorganic-P, but not to water-soluble organic-P and not to total P or other experimentally-defined stable P fractions. We conclude that the P stabilization in the sludge will allow beneficial and sustainable use of sewage sludge as a soil amendment and source of nutrients, but the stabilization method should be selected in accordance with the target soil properties.

  15. Environmental evaluation of the outdoor radiological risk from a sewage sludge irradiation plant using a consultation system

    International Nuclear Information System (INIS)

    Mangussi, M.J.; Caporale, M.C.

    2003-01-01

    The consultation system presented will be included in the environmental assessment for a sewage sludge irradiation plant working with 7000.000 Ci of cobalt 60. The system shows over suitable plans the effective dose rate at any point selected by the user or it shows the equal dose zones on a color scheme; in both situations the security recommended upper level of the effective dose is showed. The software, developed in the Borland Delphi 5 visual language, is comprehensible without high nuclear knowledge and perusing it will be easy for the environmental authorities as well as for common people. (author)

  16. Changes of micronutrients, dry weight and plant development in ...

    African Journals Online (AJOL)

    User

    2011-05-09

    May 9, 2011 ... Fe content of the leaf in lettuce. In the root part of the plants, Mn content increased for. Omaha, Spok, Semu DNK-207NA, Tower, Semu209/81 and Lirawell in the salt stress treatment, however, its con- centration decreased in the other cultivars. Mn content decreased with salt stress in the shoot of plants in.

  17. WWTP design in warm climates - guideline comparison and parameter adaptation for a full-scale activated sludge plant using mass balancing.

    Science.gov (United States)

    Walder, C; Lindtner, S; Proesl, A; Klegraf, F; Weissenbacher, N

    2013-01-01

    The ATV-A-131 guideline and the design approach published in 'Wastewater Engineering, Treatment and Reuse (WE)' are widely used for the design of activated sludge plants. They are both based on simplified steady-state assumptions tailored to the boundary conditions of temperate climates. Using design guidelines beyond the designated temperature range may lead to inappropriate results. The objectives of this paper are (1) to summarise temperature relevant differences between ATV-A-131 and WE; (2) to show the related design components; and (3) to demonstrate a procedure for design parameter adaptation for a full-scale activated sludge plant located in a warm climate region. To gain steady-state data required for wastewater treatment plant (WWTP) design according to ATV-A-131 and WE, full-scale plant data were acquired for a period of 6 months as a basis for analyses and adaptation. Mass balances were calculated for the verification of the measurements and for analysing excess sludge production. The two approaches showed relevant temperature related differences. WE default application resulted in lower deviation in the mass balance results for excess sludge production. However, with the adaptation of the heterotrophic decay rates for both approaches and the inert organic and mineral solids fraction additionally for ATV-A-131, a good fit to the observed excess sludge production could be achieved.

  18. Sludge pumping in water treatment

    International Nuclear Information System (INIS)

    Solar Manuel, M. A.

    2010-01-01

    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.

  19. Diversity and ecological ranges of plant species from dry inter-Andean valleys

    DEFF Research Database (Denmark)

    Quintana, Catalina

    and neighboring habitats like mountain forests, páramos, Pacific and Amazonian lowlands. No prior study of dry valleys anywhere in the Neotropics has explored how species are shared with other habitats. 4) This paper presents a spatial hierarchical prioritization analysis for 95 species of DIAVs vegetation......Dry valleys in the American Andes and other mountains have provided excellent agricultural lands since millennia. Besides agriculture, wood extraction and the establishment of urban areas have diminished the native vegetation of these valleys. Consequently the original vegetation is now mostly...... found on steep slopes and in ravines. These areas of original dry valley vegetation preserve many wild relatives of cultivated plants on the one hand and old lineages of other wild plant groups. Dry inter-Andean valleys (DIAVs) in Ecuador therefore makeup a biodiversity hot spot for both plants...

  20. Diversity and ecological ranges of plant species from dry inter-Andean valleys

    DEFF Research Database (Denmark)

    Quintana, Catalina

    Dry valleys in the American Andes and other mountains have provided excellent agricultural lands since millennia. Besides agriculture, wood extraction and the establishment of urban areas have diminished the native vegetation of these valleys. Consequently the original vegetation is now mostly...... found on steep slopes and in ravines. These areas of original dry valley vegetation preserve many wild relatives of cultivated plants on the one hand and old lineages of other wild plant groups. Dry inter-Andean valleys (DIAVs) in Ecuador therefore makeup a biodiversity hot spot for both plants...... of Ecuadorian dry inter-Andean valleys vegetation, including information related to the physical settings as well as to the vegetation and flora of the valleys. 2) This chapter unveils the influence of disturbance, water availability and low temperature in shaping species composition and occurrence. We found...

  1. Evolution of reuse of sludge from water treatment plant in the red ceramic industry

    International Nuclear Information System (INIS)

    Rodrigues, R.A.; Martins, B.E.D.B.S.; Couto, V.M.P.; Campos, J.C.; Almeida, V.C.

    2011-01-01

    The ceramic industry has enormous potential to absorb wastes. The main objective of this study was to investigate whether the use of a sludge (WTP) in the physical and mechanical properties of the burning of a red ceramic body. Compositions were prepared with different percentages of mud by the method of forming the pressed and sintered at 900 deg C, 1000 deg C and 1100 ° C. The specimens were tested for linear shrinkage, water absorption, porosity and stress rupture flexion. Were characterized by X-ray fluorescence, X-ray diffraction and Scanning Electron Microscopy. The results show that the incorporation of sludge WTP changes the quality of ceramics. (author)

  2. How plants keep dry: a physicist's point of view.

    Science.gov (United States)

    Otten, Alexander; Herminghaus, Stephan

    2004-03-16

    This work describes the investigation of the physical basis of the amazing water repellence of some plant leaves, which is in addition to self-cleaning properties known as the "Lotus effect". Two rather different possible mechanisms are proposed, which are suggested to cover the main physics in a majority of superhydrophobic systems. These concepts are illustrated with two different types of plant leaves as well as a model surface carrying carbon nanotube aggregates.

  3. Occurrence of pharmaceutical compounds in wastewater and sludge from wastewater treatment plants: removal and ecotoxicological impact of wastewater discharges and sludge disposal.

    Science.gov (United States)

    Martín, J; Camacho-Muñoz, D; Santos, J L; Aparicio, I; Alonso, E

    2012-11-15

    The occurrence of sixteen pharmaceutically active compounds in influent and effluent wastewater and in primary, secondary and digested sludge in one-year period has been evaluated. Solid-water partition coefficients (Kd) were calculated to evaluate the efficiency of removal of these compounds from wastewater by sorption onto sludge. The ecotoxicological risk to aquatic and terrestrial ecosystems, due to wastewater discharges to the receiving streams and to the application of digested sludge as fertilizer onto soils, was also evaluated. Twelve of the pharmaceuticals were detected in wastewater at mean concentrations from 0.1 to 32 μg/L. All the compounds found in wastewater were also found in sewage sludge, except diclofenac, at mean concentrations from 8.1 to 2206 μg/kg dm. Ibuprofen, salicylic acid, gemfibrozil and caffeine were the compounds at the highest concentrations. LogKd values were between 1.17 (naproxen) and 3.48 (carbamazepine). The highest ecotoxicological risk in effluent wastewater and digested sludge is due to ibuprofen (risk quotient (RQ): 3.2 and 4.4, respectively), 17α-ethinylestradiol (RQ: 12 and 22, respectively) and 17β-estradiol (RQ: 12 and 359, respectively). Ecotoxicological risk after wastewater discharge and sludge disposal is limited to the presence of 17β-estradiol in digested-sludge amended soil (RQ: 2.7). Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Extracellular polymeric substances (EPS) producing bacterial strains of municipal wastewater sludge: isolation, molecular identification, EPS characterization and performance for sludge settling and dewatering.

    Science.gov (United States)

    Bala Subramanian, S; Yan, S; Tyagi, R D; Surampalli, R Y

    2010-04-01

    Wastewater treatment plants often face the problems of sludge settling mainly due to sludge bulking. Generally, synthetic organic polymer and/or inorganic coagulants (ferric chloride, alum and quick lime) are used for sludge settling. These chemicals are very expensive and further pollute the environment. Whereas, the bioflocculants are environment friendly and may be used to flocculate the sludge. Extracellular polymeric substances (EPS) produced by sludge microorganisms play a definite role in sludge flocculation. In this study, 25 EPS producing strains were isolated from municipal wastewater treatment plant. Microorganisms were selected based on EPS production properties on solid agar medium. Three types of EPS (slime, capsular and bacterial broth mixture of both slime and capsular) were harvested and their characteristics were studied. EPS concentration (dry weight), viscosity and their charge (using a Zetaphoremeter) were also measured. Bioflocculability of obtained EPS was evaluated by measuring the kaolin clay flocculation activity. Six bacterial strains (BS2, BS8, BS9, BS11, BS15 and BS25) were selected based on the kaolin clay flocculation. The slime EPS was better for bioflocculation than capsular EPS and bacterial broth. Therefore, extracted slime EPS (partially purified) from six bacterial strains was studied in terms of sludge settling [sludge volume index (SVI)] and dewatering [capillary suction time (CST)]. Biopolymers produced by individual strains substantially improved dewaterability. The extracted slime EPS from six different strains were partially characterized. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  5. Stepwise drying of medicinal plants as alternative to reduce time and energy processing

    Science.gov (United States)

    Cuervo-Andrade, S. P.; Hensel, O.

    2016-07-01

    The objective of drying medicinal plants is to extend the shelf life and conserving the fresh characteristics. This is achieved by reducing the water activity (aw) of the product to a value which will inhibit the growth and development of pathogenic and spoilage microorganisms, significantly reducing enzyme activity and the rate at which undesirable chemical reactions occur. The technical drying process requires an enormous amount of thermal and electrical energy. An improvement in the quality of the product to be dried and at the same time a decrease in the drying cost and time are achieved through the utilization of a controlled conventional drying method, which is based on a good utilization of the renewable energy or looking for other alternatives which achieve lower processing times without sacrificing the final product quality. In this work the method of stepwise drying of medicinal plants is presented as an alternative to the conventional drying that uses a constant temperature during the whole process. The objective of stepwise drying is the decrease of drying time and reduction in energy consumption. In this process, apart from observing the effects on decreases the effective drying process time and energy, the influence of the different combinations of drying phases on several characteristics of the product are considered. The tests were carried out with Melissa officinalis L. variety citronella, sowed in greenhouse. For the stepwise drying process different combinations of initial and final temperature, 40/50°C, are evaluated, with different transition points associated to different moisture contents (20, 30, 40% and 50%) of the product during the process. Final quality of dried foods is another important issue in food drying. Drying process has effect in quality attributes drying products. This study was determining the color changes and essential oil loses by reference the measurement of the color and essential oil content of the fresh product was

  6. Heavy metals in a degraded soil treated with sludge from water treatment plant

    Directory of Open Access Journals (Sweden)

    Teixeira Sandra Tereza

    2005-01-01

    Full Text Available The application of water treatment sludge (WTS to degraded soil is an alternative for both residue disposal and degraded soil reclaim. This study evaluated effects of the application of water treatment sludge to a Typic Hapludox soil degraded by tin mining in the National Forest of Jamari, State of Rondonia, Brazil, on the content of heavy metals. A completely randomized experimental design with five treatments was used: control (n = 4; chemical control, which received only liming (n = 4; and rates D100, D150 and D200, which corresponded to 100, 150 and 200 mg of N-sludge kg-1 soil (n = 20, respectively. Thirty days after liming, period in which soil moisture was kept at 70% of the retention capacity, soil samples were taken and analyzed for total and extractable Fe, Cu, Mn, Zn, Cd, Pb, Ni, and Cr. The application of WTS increased heavy-metal contents in the degraded soil. Although heavy metals were below their respective critical limits, sludge application onto degraded areas may cause hazardous environmental impact and thus must be monitored.

  7. Plant biomass increase linked to biological activity in soils amended with sewage sludge compost

    International Nuclear Information System (INIS)

    Ibanez-Burgos, A.; Lopez-Lopez, G.; Vera, J.; Rovira, J. M.; Reolid, C.; Sastre-Conde, I.

    2009-01-01

    Sewage sludge compost application to almond tree plantations presents a potential management alternative to combat soil mismanagement in Mediterranean areas where almonds are grown. this practice could also be used to restore vegetable biomass to soils which are not fertile enough to support other crops, as well as to fight climatic change. (Author)

  8. The effect of sewage sludge on heavy metal concentrations in wheat plant (Triticum aestivum L.).

    Science.gov (United States)

    Shahbazi, Fatemeh; Ghasemi, Somayeh; Sodaiezadeh, Hamid; Ayaseh, Kobra; Zamani-Ahmadmahmoodi, Rasool

    2017-06-01

    The use of sewage sludge in agricultural soils can improve soil physical and chemical properties and soil fertility by increasing organic materials; however, the presence of heavy metals in sewage sludge is a significant problem for the quality of agricultural products and the environment. Most heavy metals, due to their inactive nature, are stable and can affect human health. This study investigates the effect of sewage sludge on the concentration of copper, zinc, cadmium, lead, iron, and manganese in two varieties of wheat, i.e., Sivand (Triticum aestivum cv. Sivand) and Roshan (Triticum aestivum cv. Roshan). Results were obtained from a factorial experiment in a completely randomized design with three replications and at three levels (0, 60, and 120 kg soil) and were carried out in a research greenhouse. This research concluded that in the treated seed and stem of Sivand variety, concentrations of Zn, Cd, Fe, and Mn were below the standard toxicity limit, and concentrations of Cu and Pb were above the standard limit. In the Roshan variety, the concentrations of Zn, Cd, Pb, Fe, and Mn were below the standard limit, and Cu concentration was above the standard. The results of this study lead to the recommendation that farmers avoid using sewage sludge in farming, as much as possible. Instead, it is far more appropriately employed as a fertilizer for green space, ornamental trees, and parks, where edible products for human consumption are not grown.

  9. Bioavailable and biodegradable dissolved organic nitrogen in activated sludge and trickling filter wastewater treatment plants

    Science.gov (United States)

    A study was carried out to understand the fate of biodegradable dissolved organic nitrogen (BDON) and bioavailable dissolved organic nitrogen (ABDON) along the treatment trains of a wastewater treatment facility (WWTF) equipped with an activated sludge (AS) system and a WWTF equipped with a two-stag...

  10. Reuse of By-Products from Ready-Mixed Concrete Plants for the Production of Cement Mortars

    Directory of Open Access Journals (Sweden)

    Monika Zervaki

    2013-06-01

    Full Text Available This study was motivated by the necessity to recycle sludge water resulting from washing out concrete mixing trucks - a problem of both environmental and economic importance for the ready-mixed concrete industry. Sludge water from ready-mixed concrete plants as well as dry sludge, which is derived from the settling of the water, are hazardous for disposal due to their high pH value (pH>11.5. In this work, cement mortars were composed using either sludge water after various treatment, or dry sludge in several ratios. The cement mortars were tested for their workability and strength development. The purpose of this experimental design was to prove that sludge water, as well as sludge in a wet or dry form, can be used in the production of mortars without degrading any of their properties.

  11. Quantification of potentially toxic elements in sewage and sludge from treatment plants in the cities of Campinas and Jaguariuna using synchrotron radiation total reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Souza, Luciana Carla Ferreira de; Canteras, Felippe Benavente; Moreira, Silvana

    2013-01-01

    The rapid urban and industrial development in last decades has brought as one of the consequences, changes in the environment. The lack of planning of city growth is, today, one of the major causes of water pollution including residential, industrial, agricultural, and hospital waste. The metals contamination is a major problem, causing serious changes to the environment, causing harm to human health. The sludge generated at sewage treatment plants, is an important source of nutrients and organic matter, and therefore it can also be reused mainly for agricultural use, since contaminants are removed. The cities of Campinas and Jaguariuna are inserted in the Campinas Metropolitan Region (CMR), one of the most dynamic regions in the Brazilian economy. Therefore, to study the anthropogenic influences of the cities, evaluated the quality of raw and treated effluent and the sludge generated in sewage treatment plants, especially with regard to heavy metals. Measurements of metals were performed by Synchrotron Radiation Total Reflection X-ray Fluorescence. For treated effluent data were compared to CONAMA 357 law and Cr, Mn, Fe, Ni, Cu, Zn, Ba and Pb showed concentrations in according with the law. To reuse in agriculture the contents were compared to the limits defined by CETESB and some elements had concentrations above to the permitted preventing its reuse. For sludge, Cr, Ni, Cu, Zn, Ba and Pb, in the two treatment plants studied, the concentrations were lower than the maximum permissible values established by CONAMA 375 law allowing the sludge application sludge on agricultural land. (author)

  12. Screening the environmental fate of organic contaminants in sewage sludges applied to agricultural soils: II. The potential for transfers to plants and grazing animals.

    Science.gov (United States)

    Duarte-Davidson, R; Jones, K C

    1996-06-21

    This is the second of two papers which screen the environmental fate of sludge organic contaminants when applied to agricultural land. A simple screening model has been developed to assess the likelihood of organic contaminants accumulating into the food-chain following the application of sludge into arable and pasture land. The purpose of this exercise is to highlight those compounds that have the potential to accumulate into plants and animal tissues using data on physico-chemical properties of the compounds of interest. Over 300 organic compounds or groups of compounds which have been identified as potential pollutants in sludge have been screened for their potential to transfer from sludge-amended soils to plants via retention by root surfaces, root uptake and translocation, foliar uptake and animal intake via soil and herbage ingestion. Various organic contaminants have been identified as having a high potential to transfer into the food-chain through plant and animal accumulation. Two priority lists have been produced to include (a) those compounds which are shown as being of sufficient or suspected importance, but for which further sludge concentration data and fate studies would be necessary to check on their status, and (b) those compounds which have been highlighted in the screening processes as having a high potential to accumulate up the food-chain. This screening approach can be adapted to other chemicals as information on new chemicals and their physico-chemical properties becomes available.

  13. Losses of the elements during dry ashing of plant materials

    International Nuclear Information System (INIS)

    Nonaka, Nobuhiro; Higuchi, Hideo; Hamaguchi, Hiroshi; Tomura, Kenji.

    1981-01-01

    Dry ashing technique has been considered to cause potential errors due to loss of elements by volatilisation or by reaction with the vessel. To obtain an overall view of elemental loss, the dry ashing was applied to the standard reference materials such as Orchard leaves(NBS) and Bamboo leaves. The ashing condition was as follows; The temperature varied from 200 0 C to 800 0 C by stepwise heating and the duration of heating at each temperature was 24 h. Concentrations of 25 elements in a sample were determined by means of atomic absorption spectrometry and neutron activation analysis using a Ge(Li) detector. The results obtained were as follows; (1) The losses for alkali elements were dependent on crucible materials and sample species. The losses increased with temperature and they were serious when a silica dish was used. (2) The loss for mercury was found above 110 0 C and simply increased with temperature. On the other hand, chlorine, bromine, selenium and chromium showed complicated patterns in which the first losses occurred at 200 0 C, no additional losses being observed at each following step of heating between 200 0 C and 450 0 C, and they increased again above 500 0 C. (3) The losses for arsenic and antimony occurred at 200 0 C, but any losses could not be observed above 200 0 C. (4) No losses were detected over the temperature range studied for alkaline earths, rare earths, vanadium, manganese, iron, cobalt, zinc and aluminum. (author)

  14. Monitoring of sludge dewatering equipment by image classification

    Science.gov (United States)

    Maquine de Souza, Sandro; Grandvalet, Yves; Denoeux, Thierry

    2004-11-01

    Belt filter presses represent an economical means to dewater the residual sludge generated in wastewater treatment plants. In order to assure maximal water removal, the raw sludge is mixed with a chemical conditioner prior to being fed into the belt filter press. When the conditioner is properly dosed, the sludge acquires a coarse texture, with space between flocs. This information was exploited for the development of a software sensor, where digital images are the input signal, and the output is a numeric value proportional to the dewatered sludge dry content. Three families of features were used to characterize the textures. Gabor filtering, wavelet decomposition and co-occurrence matrix computation were the techniques used. A database of images, ordered by their corresponding dry contents, was used to calibrate the model that calculates the sensor output. The images were separated in groups that correspond to single experimental sessions. With the calibrated model, all images were correctly ranked within an experiment session. The results were very similar regardless of the family of features used. The output can be fed to a control system, or, in the case of fixed experiment conditions, it can be used to directly estimate the dewatered sludge dry content.

  15. Dry fractionation for sustainable production of plant protein concentrates

    NARCIS (Netherlands)

    Pelgrom, P.J.M.

    2015-01-01

    The global demand for protein-rich foods is expected to double in the coming decades due to the increasing prosperity and world population. To keep up with the demand, the transition from an animal to a plant-based protein supply is desirable from long-term economic and environmental perspectives.

  16. Effects of sewage sludge on the yield of plants in the rotation system of wheat-white head cabbage-tomato

    Directory of Open Access Journals (Sweden)

    Mehmet Arif Özyazıcı

    2013-01-01

    Full Text Available This research was carried to determine the effects of sewage sludge applications on the yield and yield components of plants under crop rotation system. The field experiments were conducted in the Bafra Plain, located in the north region of Turkey. In this research, the “wheat-white head cabbage-tomato” crop rotation systems have been examined and the same crop rotation has been repeated in two separate years and field trials have been established. Seven treatments were compared: a control without application of sludge nor nitrogen fertilization, a treatment without sludge, but nitrogen and phosphorus fertilization, applied at before sowing of wheat and five treatments where, respectively 10, 20, 30, 40 and 50 tons sludge ha-1. The experimental design was a randomized complete block with three replications. The results showed that all the yield components of wheat and yield of white head cabbage and tomato increased significantly with increasing rates of sewage sludge as compared to control. As a result, 20 t ha-1 of sewage sludge application could be recommended the suitable dose for the rotation of wheat-white head cabbage-tomato in soil and climatic conditions of Bafra Plain.

  17. A Study of the Utilization of Palm Fruit Sludge for Food Preparations ...

    African Journals Online (AJOL)

    In the study, palm fruit sludge was recovered and used in human food preparation. The sludge was obtained from palm fruit waste liquid through filtration and dewatering. The wet sludge was dried at 50°C, milled into powder and sieved to obtain the dry powder. Proximate analysis of the dry sludge showed that it contained ...

  18. Opportunities for energy conservation and load shaping in sludge management systems

    International Nuclear Information System (INIS)

    Burton, F.L.

    1992-11-01

    Expansion of both water and wastewater treatment plants increases the quantity of resulting sludge that must be processed. This report focuses on alternative sludge processing technologies, which may pre sent opportunities for managing the amount of electricity required to power processing equipment. Overall, the report provides information on the electrotechnologies used in sludge management systems, defines opportunities in the design and operation of water and wastewater sludge management systems for more efficient use of electric power, and identifies possible areas for research and development that would enhance the design of energy-efficient systems. The sludge operations and processes covered in this report include pumping, thickening, stabilization, conditioning and dewatering, heat drying, and thermal reduction

  19. Evaluation of heavy metal content in irradiated sludge, chicken manure and fertilized soil in Indonesia

    International Nuclear Information System (INIS)

    Hilmy, N.; Suwirma, S.; Surtipanti, S.; Harsojo

    1997-01-01

    The contents of heavy metals, Hg, Cd, Cr, Cu, Ni, Pb, Zn and Co, were determined in two irradiated sludges, chicken manure and fertilized soil. Sludge I was collected from a treatment plant in Jakarta city, Sludge II from a sludge reservoir in a Jakarta suburb, chicken manure was obtained from a farm south of Jakarta, and the soil had been treated with phosphate fertilizer since 1967. The sludges and chicken manure were collected during the rainy and dry seasons, and the heavy-metal contents were determined by atomic-absorption spectrometry and neutron-activation analysis. The results obtained are compared with data from Canada, and are discussed in terms of permissible limits in the environment. (author)

  20. Usage of hybrid solar collector system in drying technologies of medical plants

    International Nuclear Information System (INIS)

    Čiplienė, Aušra; Novošinskas, Henrikas; Raila, Algirdas; Zvicevičius, Egidijus

    2015-01-01

    Highlights: • Solar radiation energy utilization in drying technologies. • Accumulation of solar radiation energy. • The system comprising two different solar collector types. • Preparation of the drying agent by employing solar radiation energy around the clock. • The energy resources saving technology for medicinal plants’ raw material processing and drying. - Abstract: In the temperate climate zone under natural conditions, medicinal plants drying up to 8–12% moisture content and preparation of the quality medicinal plant’s raw material are complicated tasks. In many cases drying process of medicinal plants raw material, particularly rich in volatile compounds, needs the optimal drying temperatures of 30–45 °C and relative humidity not higher than 50–60%. In Lithuania, located in the northern part of the temperate climate zone, in summer the average temperature of ambient air is 16.1 ± 0.5 °C, and relative humidity is 77.3 ± 1.8%. In order to improve the sorption properties of ambient air, it is heated up to the admissible drying temperature. The experimental dryer was developed comprising two different solar collectors: the air type solar collector with area 12 m 2 for direct heating of the drying agent and the flat-plate type solar collector (8 m 2 ) for accumulation of converted heat energy. The research of motherwort (Leonurus cardiaca L.) drying was carried out in the dryer. It was determined that by combining operation of two different solar collectors, the solar radiation energy for drying agent’s heating could be used continuously around the clock by employing the accumulated energy, in order to compensate the solar irradiance variability and to ensure stability of the drying process. In the daytime the air-type solar collector at an airflow equal to 367 m 3 h −1 , i.e. at comparative flow of the drying agent per ton of dried medicinal plant raw material – 2450 m 3 h −1 , heats the air up to 30 °C when the solar

  1. User's manual for the BNW-II optimization code for dry/wet-cooled power plants

    International Nuclear Information System (INIS)

    Braun, D.J.; Bamberger, J.A.; Braun, D.J.; Faletti, D.W.; Wiles, L.E.

    1978-05-01

    The User's Manual describes how to operate BNW-II, a computer code developed by the Pacific Northwest Laboratory (PNL) as a part of its activities under the Department of Energy (DOE) Dry Cooling Enhancement Program. The computer program offers a comprehensive method of evaluating the cost savings potential of dry/wet-cooled heat rejection systems. Going beyond simple ''figure-of-merit'' cooling tower optimization, this method includes such items as the cost of annual replacement capacity, and the optimum split between plant scale-up and replacement capacity, as well as the purchase and operating costs of all major heat rejection components. Hence the BNW-II code is a useful tool for determining potential cost savings of new dry/wet surfaces, new piping, or other components as part of an optimized system for a dry/wet-cooled plant

  2. Drying of sewage sludge using the ECACTHERM {sup trademark} process; Trocknung von Abwasserschlaemmen mit dem ECACTHERM {sup trademark} Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Gerl, S. [Maschinenfabrik Gustav Eirich GmbH und Co KG, Hardheim (Germany)

    2003-07-01

    This is an established process in many fields of industry. For drying, superheated water vapour is introduced into a mechanically fluidized bed. The granulated end products are cooled in a vacuum using the cold generated by evaporation cooling. In partial vacuum and in a closed-loop process, drying and granulation take place in inert conditions, without unpleasant smell and with minimum energy consumption. (orig.) [German] Der EVACTHERM {sup trademark} Vakuumheissdampftrocknungsprozess in einem Eirich Mischreaktor ist seit vielen Jahren in den verschiedensten Industriebereichen zur Schlammaufbereitung erfolgreich im Einsatz. Die Trocknung erfolgt durch Einleitung von ueberhitztem Wasserdampf in ein mechanisch erzeugtes Wirbelbett. Die Kuehlung des granulierten Endproduktes wird durch Anlegen von Vakuum unter Ausnutzung der Verdampfungskuehlung erzielt. Durch die Aufbereitung im leichten Unterdruck und dem Betrieb in geschlossener Kreislauffuehrung mit ueberhitztem Dampf, erfolgt die Trocknung und Granulierung unter inerten Bedingungen, ohne Geruchsemissionen und bei minimalem Energieverbrauch. (orig.)

  3. The Relation between Polyaromatic Hydrocarbon Concentration in Sewage Sludge and Its Uptake by Plants: Phragmites communis, Polygonum persicaria and Bidens tripartita

    Science.gov (United States)

    Gworek, Barbara; Klimczak, Katarzyna; Kijeńska, Marta

    2014-01-01

    The aim of the study was to define the relationship between the concentration of PAHs in sewage sludge at a particular location and their amount in various plant materials growing on it. The credibility of the results is enhanced by the fact that sewage sludge from two separate sewage-treatment plants were selected for their influence on the content of PAHs in three plant species growing on them. The investigations were carried out for a period of three years. The results demonstrated unequivocally that the uptake of PAHs by a plant depended on polyaromatic hydrocarbon concentration in the sewage sludge. The correlation between accumulation coefficient of PAH in a plant and the content of the same PAH in the sewage sludge had for three-, four- and five-ring hydrocarbons an exponential character and for six-ring hydrocarbons was of a linear character. The accumulation coefficients calculated for three-ring aromatics were several times higher than for four-ring PAHs; further the coefficient values calculated for five-ring PAHs were several times lower than for four-ring hydrocarbons. Finally, the accumulation coefficient values of six-ring PAHs were the lowest in the series of studied polyaromatic hydrocarbons. PMID:25310699

  4. Sewage sludge pasteurization by gamma radiation: Financial viability case studies

    Science.gov (United States)

    Swinwood, Jean F.; Kotler, Jiri

    This paper examines the financial viability of sewage sludge pasteurization by gamma radiation, by examining the following three North American scenarios: 1) Small volume sewage treatment plant experiencing high sludge disposal costs. 2) Large volume sewage treatment plant experiencing low sludge disposal costs. 3) Large volume sewage treatment plant experiencing high sludge disposal costs.

  5. Sewage sludge pasteurization by gamma radiation: financial viability case studies

    International Nuclear Information System (INIS)

    Swinwood, J.F.; Kotler, J.

    1990-01-01

    This paper examines the financial viability of sewage sludge pasteurization by gamma radiation, by examining the following three North American scenarios: 1. Small volume sewage treatment plant experiencing high sludge disposal costs; 2. Large volume sewage treatment plant experiencing low sludge disposal costs; 3. Large volume sewage treatment plant experiencing high sludge disposal costs. (author)

  6. IDENTIFICATION OF RICE (Oryza sativa L. VARIETIES SUITABLE FOR DRY SEASON AND WET SEASON PLANTING

    Directory of Open Access Journals (Sweden)

    Sumarno Sumarno

    2013-07-01

    Full Text Available Rice planting on dry and wet seasons faces a specific climatological characteristic, which affects directly on rice growth and yield. Fifteen rice genotypes were evaluated for their seasonal planting adaptation at Sukamandi Experimental Station, Subang, West Java, during the dry and wet seasons of 2009-2010. Randomized complete block design with three replications was applied on the experiment. Plot size was 4 m x 6 m and plant spacing was 20 cm x 20 cm. Standard agronomic practices were applied on both planting season experiments. Data were collected for major morphological traits, days to grain maturity and grain yield, measured on wet and dry basis (11% moisture content. Data were analysed for analyses of variance for each season and for combined seasons, and mean values separation of the variable used the 5% Duncan Multiple Range Test. Correlation between grain yields and morphological variable data were computed for each season and for combined seasons. The correlation coefficients of variables and grain yield were partitioned into direct and indirect causes using path analyses. Combined analyses of variances indicated significant effects of genotypes, seasons and genotypes x seasons interaction for almost all variables, including grain yields, suggesting there were seasonal adaptation specificity among genotypes. Five genotypes were identified as suitable for dry season planting, and nine genotypes as suitable for wet season planting. Among those genotypes, three genotypes, namely Mekongga, Inpari-10 and OM 5240 were suitable for both dry and wet season planting. Ciherang and Cigeulis varieties were more suitable for dry season, while Cibogo, Inpari-1, Inpari-3, Inpari-5, and Inpari-8 were more suitable for wet season planting. Adopting the most productive rice varieties for planting on dry or wet season as was suggested on this research should increase rice production substantially. To facilitate the

  7. Natural-draught dry cooling tower for steam power plants

    International Nuclear Information System (INIS)

    Nasser, G.E.D.

    1977-01-01

    The problem of making natural-draught cooling towers for large steam power plants as simple, compact, and economical as possible can be solved by a combination of well-known structural features: The condenser elements, which are designed as stacks of plates with corrugated surfaces, are arranged in the form of a truncated pyramid enlarged at the top. In the cooling air flow, there are openings for feeding in superheated gas from the lower part of the cupola. (HP) [de

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

    Directory of Open Access Journals (Sweden)

    Neamat Jaafarzadeh Haghighi Fard

    2015-09-01

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

  9. Do competitive interactions in dry heathlands explain plant abundance patterns and species coexistence?

    DEFF Research Database (Denmark)

    Ransijn, Johannes; Damgaard, Christian; Schmidt, Inger K

    2015-01-01

    Plant community patterns in space and time may be explained by the interactions between competing plant species. The presented study investigates this in a nutrient and species poor ecosystem. The study presents a methodology for inferring competitive interactions from yearly vegetation inventories...... and uses this to assess the outcome of competitive interactions and to predict community patterns and dynamics in a Northwest-European dry heathland. Inferred competitive interactions from five consecutive years of measurements in permanent vegetation frames at a single dry heathland site were used...... to predict the community dynamics of C. vulgaris and D. flexuosa. This was compared with the observed plant community structure at 198 Danish dry heathland sites. Interspecific competition will most likely lead to competitive exclusion of D. flexuosa at the observed temporal and spatial scale...

  10. IDENTIFICATION AND AUTHENTICATION OF DRY SAMPLES OF SOME MEDICINAL PLANTS USING LEAF EPIDERMAL FEATURES AS MARKER

    Directory of Open Access Journals (Sweden)

    Abdullahi Alanamu ABDULRAHAMAN

    2016-06-01

    Full Text Available Herbal medicine is the oldest and still the most widely used system of medicine in the world today and they are made exclusively from plants. However, most of these medicines or drugs are adulterated due to lack of proper identification of the plant samples. Method of checking adulteration of drug plants is the main focus of this study. The identification and authentication of dry samples of some medicinal plants were carried out using anatomical features. Twenty-five (25 plants materials were collected in Ibadan and Ilorin, Nigeria. The plants studied include Azardiracta indica, Newboudia leavis, Polyalthia longifolia, Cymbopogon citratus, Anarcardium occidentalis, Nicotiana tobbaccum, Jatropha curcas, Chromoleana odorata, Mangifera indica, Terminalia catappa, Ocimum gratisimum, Morus messosygia, Morinda lucida, Psidium guajava, Vitellaria paradoxa, Annona senegalensis, Vernonia amygdalina, Gliricidium sepium, Ravoulvia vomitora, Telferia occindentalis Citrus aurantifolia, C. limon, C. paradisi and C. sinensis. Leaf epidermal anatomy of these selected plants showed no major variations in stomatal complex types, frequency, size and shape of stomatal cells, epidermal cell wall and trichomes between fresh and dry samples. The variations that occur were between different species but not within species. Leaf epidermal anatomy, therefore, proved to be a significant tool for resolution of taxonomic confusion of dried samples of these plants.

  11. Loss of selenium in drying and storage of agronomic plant species

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel

    1970-01-01

    In two experiments with Se75, loss of selenium from agricultural species was noted during both drying and storage. The loss of selenium during drying was to some extent overshadowed by the influence of self-absorption caused by the water in the fresh material. The results showed that even plant m...... material of non-indicator plantslose volatile selenium at drying temperatures of 60°C or higher, and in some cases even at temperatures below 60°C. The results also showed that storage as briquettes gives the lowest storage loss of selenium....

  12. Disturbance In Dry Coastal Dunes Promotes Diversity Of Plants And Arthropods

    DEFF Research Database (Denmark)

    Brunbjerg, Ane Kirstine; Jørgensen, Gorm Pilgaard; Nielsen, Kristian Mandsberg

    2015-01-01

    of three disturbance types (burning, trampling and blowouts) on plant and arthropod species richness and composition in dry coastal dunes in Jutland, Denmark. Environmental variables, plant presence–absence and arthropod abundance were measured in 150 1 × 2 m plots along transects in blowouts, burned areas...... on plant and arthropod composition. Indicator species analysis revealed plant and arthropod species indicative for different disturbances. Plant and arthropod species richness and the number of annual plant species generally increased with disturbance, and plant and arthropod richness and composition...... responded differently to different disturbances. Arthropod communities were more diverse in disturbed plots and hosted species often found in early successional habitats of potential conservation value. Disturbance promoted β-diversity, but affected plants more than arthropods, likely because...

  13. Screw pyrolysis technology for sewage sludge treatment.

    Science.gov (United States)

    Tomasi Morgano, Marco; Leibold, Hans; Richter, Frank; Stapf, Dieter; Seifert, Helmut

    2018-03-01

    Sewage sludge quantities have grown continuously since the introduction of the European Directive (UWWTD 91/271/EEC) relating to the treatment of urban wastewater. In the present, most of the sewage sludge is combusted in single fuels incineration plants or is co-fired in waste incineration or coal power plants. The combustion of sewage sludge is a proven technology. Other treatments, such as fluidized bed gasification, were successfully adopted to produce suitable syngas for power production. Besides, the number of large wastewater treatment plants is relatively small compared to the local rural ones. Moreover, alternative technologies are arising with the main target of nutrients recovery, with a special focus on phosphorus. The aforementioned issues, i.e. the small scale (below 1MW) and the nutrients recovery, suggest that pyrolysis in screw reactors may become an attractive alternative technology for sewage sludge conversion, recovery and recycling. In this work, about 100kg of dried sewage sludge from a plant in Germany were processed at the newly developed STYX Reactor, at KIT. The reactor combines the advantages of screw reactors with the high temperature filtration, in order to produce particle and ash free vapors and condensates, respectively. Experiments were carried out at temperatures between 350°C and 500°C. The yield of the char decreased from 66.7wt.% to 53.0wt.%. The same trend was obtained for the energy yield, while the maximum pyrolysis oil yield of 13.4wt.% was obtained at 500°C. Besides mercury, the metals and the other minerals were completely retained in the char. Nitrogen and sulfur migrated from the solid to the condensate and to the gas, respectively. Based on the energy balance, a new concept for the decentral production of char as well as heat and power in an externally fired micro gas turbine showed a cogeneration efficiency up to about 40%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Irrigation and Maize Cultivation Erode Plant Diversity Within Crops in Mediterranean Dry Cereal Agro-Ecosystems

    Science.gov (United States)

    Fagúndez, Jaime; Olea, Pedro P.; Tejedo, Pablo; Mateo-Tomás, Patricia; Gómez, David

    2016-07-01

    The intensification of agriculture has increased production at the cost of environment and biodiversity worldwide. To increase crop yield in dry cereal systems, vast farmland areas of high conservation value are being converted into irrigation, especially in Mediterranean countries. We analyze the effect of irrigation-driven changes on the farm biota by comparing species diversity, community composition, and species traits of arable plants within crop fields from two contrasting farming systems (dry and irrigated) in Spain. We sampled plant species within 80 fields of dry wheat, irrigated wheat, and maize (only cultivated under irrigation). Wheat crops held higher landscape and per field species richness, and beta diversity than maize. Within the same type of crop, irrigated wheat hosted lower plant diversity than dry wheat at both field and landscape scales. Floristic composition differed between crop types, with higher frequencies of perennials, cosmopolitan, exotic, wind-pollinated and C4 species in maize. Our results suggest that irrigation projects, that transform large areas of dry cereal agro-ecosystems into irrigated crop systems dominated by maize, erode plant diversity. An adequate planning on the type and proportion of crops used in the irrigated agro-ecosystems is needed in order to balance agriculture production and biodiversity conservation.

  15. Plant absorption of trace elements in sludge amended soils and correlation with soil chemical speciation

    International Nuclear Information System (INIS)

    Torri, Silvana; Lavado, Raul

    2009-01-01

    The aim of the present study was to investigate the relationship between Lolium perenne L. uptake of Cd, Cu, Pb, and Zn in sludge amended soils and soil availability of these elements assessed by soil sequential extraction. A greenhouse experiment was set with three representative soils of the Pampas Region, Argentina, amended with sewage sludge and sewage sludge enriched with its own incinerated ash. After the stabilization period of 60 days, half of the pots were sampled for soil analysis; the rest of the pots were sown with L. perenne and harvested 8, 12, 16 and 20 weeks after sowing, by cutting just above the soil surface. Cadmium and Pb concentrations in aerial tissues of L. perenne were below detection limits, in good agreement with the soil fractionation study. Copper and Zn concentration in the first harvest were significantly higher in the coarse textured soil compared to the fine textured soil, in contrast with soil chemical speciation. In the third harvest, there was a positive correlation between Cu and Zn concentration in aerial biomass and soil fractions usually considered of low availability. We conclude that the most available fractions obtained by soil sequential extraction did not provide the best indicator of Cu and Zn availability to L. perenne.

  16. Plant absorption of trace elements in sludge amended soils and correlation with soil chemical speciation

    Energy Technology Data Exchange (ETDEWEB)

    Torri, Silvana, E-mail: torri@agro.uba.ar [Catedra de Fertilidad y Fertilizantes, Facultad de Agronomia, UBA, Avda San Martin 4453, Buenos Aires (C1417 DSE) (Argentina); Lavado, Raul [Catedra de Fertilidad y Fertilizantes, Facultad de Agronomia, UBA, Avda San Martin 4453, Buenos Aires (C1417 DSE) (Argentina)

    2009-07-30

    The aim of the present study was to investigate the relationship between Lolium perenne L. uptake of Cd, Cu, Pb, and Zn in sludge amended soils and soil availability of these elements assessed by soil sequential extraction. A greenhouse experiment was set with three representative soils of the Pampas Region, Argentina, amended with sewage sludge and sewage sludge enriched with its own incinerated ash. After the stabilization period of 60 days, half of the pots were sampled for soil analysis; the rest of the pots were sown with L. perenne and harvested 8, 12, 16 and 20 weeks after sowing, by cutting just above the soil surface. Cadmium and Pb concentrations in aerial tissues of L. perenne were below detection limits, in good agreement with the soil fractionation study. Copper and Zn concentration in the first harvest were significantly higher in the coarse textured soil compared to the fine textured soil, in contrast with soil chemical speciation. In the third harvest, there was a positive correlation between Cu and Zn concentration in aerial biomass and soil fractions usually considered of low availability. We conclude that the most available fractions obtained by soil sequential extraction did not provide the best indicator of Cu and Zn availability to L. perenne.

  17. The Influence of Gamma Irradiation on the Bacterial Growth and the Concentration of Macro nutrient Plant Elements (N,P,K) in The Sludge

    International Nuclear Information System (INIS)

    Yazid, M.; Zainul Kamal; Elin Nuraini

    2002-01-01

    The investigation of the gamma irradiation influence for bacterial growth and macro-nutrient plant element in the sludge has been done. The objective of the research is to study the gamma irradiation influence on bacterial growth and macro-nutrient plant element concentration; after that, can be determine the effective dose for killing pathogenic bacteria, while the other kind of bacteria such as the decomposer has been survived. The sludge samples was collected from the vicinity of Surabaya such as Sukolilo for sewage, PT SIER Rungkut for industrial and Dr. Sutomo hospital waste sludge. The irradiation of the sludge has been done at P3TIR-BATAN by Co-60 irradiator and the dose variation are 0, 5, 10, 15, 20 and 25 kGy. Microbiological observation was done after irradiation at FMIPA-UNAIR laboratory and the analysis of N,P,K elements by using fast neutron activation analysis. The observation involving total bacterial and one kind of pathogenic microbial which is Salmonella, from this observation can be deduced that population of total bacteria in the sludge is in the range at 1.0 x 10 7 to 3.7 x 10 8 . For every 5 kGy increment could be able to decrease total bacterial growth about 10 times, and at 25 kGy the total bacterial growth can be suppressed. The higher population of Salmonella can be found in the hospital sludge is in range of 3.0 to 3.5 x 10 5 , in the sewage sludge is 1.4 to 1.6 x 10 4 and industry is 1.0 to 1.4 x 10 3 . For the Salmonella disinfection need the 15 to 20 kGy radiation dose. From the calculation results can be known that the nitrogen content in the sludge is in the range at 1.393 ± 0.692 to 3.147 ± 0.697 % , the phosphor 3.714 ± 0.892 to 8.120 ± 1.034 % and the potassium 1.999 ± 0.523 to 4.52 ± 0.599 %. The variation of the irradiation dose 10 - 25 kGy does not have any significant influence for the macro-nutrient plant (N,P,K) content in the sludge from the industrial, the sewage or the hospital waste water treatment. (author)

  18. Comparative study of cogasification and co-combustion of communal sewage sludge in brown coal fuelled plants; Vergleich der Mitvergasung und Mitverbrennung kommunaler Klaerschlaemme in braunkohlegefeuerten Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Schiffer, H.P.; Bierbaum, K.; Adlhoch, W.; Thomas, G. [Rheinbraun AG, Koeln (Germany)

    1996-12-31

    Co-combustion and cogasification of sewage sludge in brown coal fuelled plants are compared, and an economic assessment is made. (ABI) [Deutsch] Die Mitverbrennung und Mitvergasung von Klaerschlamm in braunkohlegefeuerten Anlagen werden verglichen und auf ihre Wirtschaftlichkeit hin untersucht. (ABI)

  19. Vermiconversion of wastewater sludge from textile mill mixed with anaerobically digested biogas plant slurry employing Eisenia foetida.

    Science.gov (United States)

    Garg, V K; Kaushik, Priya; Dilbaghi, Neeraj

    2006-11-01

    Vermicomposting is commonly used for the management of organic wastes. We have investigated the potential of an epigeic earthworm, Eisenia foetida, to transform solid textile mill sludge (STMS) spiked with anaerobically digested biogas plant slurry (BPS) into vermicompost to evaluate the feasibility of vermicomposting in industries for waste management. The growth and reproduction of E. foetida was monitored in a range of different feed mixtures for 15 weeks in laboratory under controlled experimental conditions. E. foetida did not survive in fresh STMS. But worms grew and reproduced in STMS spiked with BPS feed mixtures. A greater percentage of STMS in feed mixture affected biomass gain and cocoon production by earthworms. The maximum growth was recorded in 100% BPS. The net weight gain by E. foetida in 100% BPS was two-four-fold higher than STMS-containing feed mixtures. After 15 weeks, maximum cocoons (78) were counted in 100% BPS and minimum (26) in 60% BPS+40% STMS feed. Vermicomposting resulted in pH shift toward acidic, significant reduction in C:N ratio, and increase in nitrogen, phosphorus, and potassium contents. Microbial activity measured as dehydrogenase activity increased with time up to day 75 but decreased on day 90, indicating the exhaustion of feed and decrease in microbial activity. These experiments demonstrate that vermicomposting can be an alternate technology for the recycling and environmentally safe disposal/management of textile mill sludge using an epigeic earthworm, E. foetida, if mixed with anaerobically digested BPS in appropriate ratios.

  20. Effect of ozone on the microbiological status of five dried aromatic plants.

    Science.gov (United States)

    Kazi, Martha; Parlapani, Foteini F; Boziaris, Ioannis S; Vellios, Evangelos K; Lykas, Christos

    2018-03-01

    Aromatic plants may be contaminated with a wide range of microorganisms, making them a potential health hazard when infused or added to ready-to-eat meals. To ensure safety, the effect of gaseous ozone treatment on the population of aerobic plate counts (APC), hygienic indicators (Escherichia coli, Enterococcus spp. and Enterobacteriaceae) and fungi was investigated for five dried aromatic plants: oregano, thyme, mountain tea, lemon verbena and chamomile. Selection, isolation and further fungi identification were based on the phenotypic and macro- and microscopic characteristics. Prior to ozonation, APC on five dried aromatic plants was in the range 5-7 log colony-forming units (CFU) g -1 . The APC exhibited a 4 log reduction, from around 6.5 to 2.5 in the case of oregano, and only a 1-2 log reduction for other herbs after 30 or 60 min of 4 ppm gaseous ozone treatment. Enterococcus spp. and E. coli were not detected on any of the tested dried aromatic plants. The fungi counts were 2-4 log CFU g -1 before ozonation. Aspergillus spp, Penicillium spp, Cladosporium spp, Alternaria spp, Fusarium spp., Ulocladium spp. and some unknown fungi were detected on plants before ozone treatment. Aspergillus spp. and/or Penicillium spp. were only detected on mountain tea and thyme plant material after 60 min of ozonation. The present study provides information about the efficiency of ozone on the microbial decontamination of dried aromatic plants. Treatment with gaseous ozone at 4 ppm for 30 min in the case of dried oregano and 60 min in the case of chamomile and lemon verbena could be used as alternative disinfection methods. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  1. Assessment of Heavy Metals in Municipal Sewage Sludge: A Case Study of Limpopo Province, South Africa

    Directory of Open Access Journals (Sweden)

    Kudakwashe K. Shamuyarira

    2014-03-01

    Full Text Available Heavy metals in high concentrations can cause health and environmental damage. Nanosilver is an emerging heavy metal which has a bright future of use in many applications. Here we report on the levels of silver and other heavy metals in municipal sewage sludge. Five towns in Limpopo province of South Africa were selected and the sludge from their wastewater treatment plants (WWTPs was collected and analysed. The acid digested sewage sludge samples were analysed using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS methods. The concentrations of silver found were low, but significant, in the range 0.22 to 21.93 mg/kg dry mass. The highest concentration of silver was found in Louis Trichardt town with a concentration of 21.93 ± 0.38 mg/kg dry mass while the lowest was Thohoyandou with a concentration of 6.13 ± 0.12 mg/kg dry mass. A control sludge sample from a pit latrine had trace levels of silver at 0.22 ± 0.01 mg/kg dry mass. The result showed that silver was indeed present in the wastewater sewage sludge and at present there is no DWAF guideline standard. The average Cd concentration was 3.10 mg/kg dry mass for Polokwane municipality. Polokwane and Louis Trichardt municipalities exhibited high levels of Pb, in excess DWAF guidelines, in sludge at 102.83 and 171.87 mg/kg respectfully. In all the WWTPs the zinc and copper concentrations were in excess of DWAF guidelines. The presence of heavy metals in the sewage sludge in excess of DWAF guidelines presents environmental hazards should the sludge be applied as a soil ameliorant.

  2. Assessment of heavy metals in municipal sewage sludge: a case study of Limpopo province, South Africa.

    Science.gov (United States)

    Shamuyarira, Kudakwashe K; Gumbo, Jabulani R

    2014-03-03

    Heavy metals in high concentrations can cause health and environmental damage. Nanosilver is an emerging heavy metal which has a bright future of use in many applications. Here we report on the levels of silver and other heavy metals in municipal sewage sludge. Five towns in Limpopo province of South Africa were selected and the sludge from their wastewater treatment plants (WWTPs) was collected and analysed. The acid digested sewage sludge samples were analysed using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) methods. The concentrations of silver found were low, but significant, in the range 0.22 to 21.93 mg/kg dry mass. The highest concentration of silver was found in Louis Trichardt town with a concentration of 21.93 ± 0.38 mg/kg dry mass while the lowest was Thohoyandou with a concentration of 6.13 ± 0.12 mg/kg dry mass. A control sludge sample from a pit latrine had trace levels of silver at 0.22 ± 0.01 mg/kg dry mass. The result showed that silver was indeed present in the wastewater sewage sludge and at present there is no DWAF guideline standard. The average Cd concentration was 3.10 mg/kg dry mass for Polokwane municipality. Polokwane and Louis Trichardt municipalities exhibited high levels of Pb, in excess DWAF guidelines, in sludge at 102.83 and 171.87 mg/kg respectfully. In all the WWTPs the zinc and copper concentrations were in excess of DWAF guidelines. The presence of heavy metals in the sewage sludge in excess of DWAF guidelines presents environmental hazards should the sludge be applied as a soil ameliorant.

  3. Influence of Continuous Flow Microwave Pre-Treatment on Anaerobic Digestion of Secondary Thickened Sludge for Sustainable Energy Recovery in Sewage Treatment Plant

    Science.gov (United States)

    Hephzibah, D.; Kumaran, P.; Saifuddin, N. M.

    2016-03-01

    This work elucidates the effects of pre-treatment of secondary thickened sludge (STS) for enhancement of biogas production that has great potential to generate energy for the utilization of the sewage treatment plant (STP) itself. Microwave pre-treatment has been adopted for this study. Experiment works have been designed and conducted to examine the effectiveness of continuous flow microwave pre-treatment on the solubility of STS, digestibility of STS and biogas production at a power level of 80 W for 5, 10 and 15 minutes. A few characteristics of the sewage sludge were monitored daily to identify the effect of pre-treatment on the sludge. The soluble chemical oxygen demand (SCOD)/total chemical oxygen demand (TCOD) ratio increased by 0.1, 1.0 and 1.8%, while the volatile fatty acids (VFA) concentration of the pre-treated sludge improved by 4.4, 5.1, 5.9% at the irradiation time of 5, 10 and 15 minutes, respectively at a microwave power level of 80 W. Besides that, the digestate also indicates that the pre-treated sludge undergoes efficient VS removal and TCOD removal after anaerobic digestion compared to the untreated sludge. Moreover, the biogas quantity increased by an average of 19.2, 24.1 and 32.2% in 5, 10 and 15 minutes irradiation time respectively compared to the untreated sludge. The additional quantity of biogas generated has shown a great potential for sustainable energy generation that can be utilized internally by the STP.

  4. Sewage sludge disposal in Austria

    International Nuclear Information System (INIS)

    Koch, F.

    1997-01-01

    Sewage systems serve about 70% of the Austrian population, producing 6 million m 3 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)

  5. Geochemical and Geophysical Study in a Degraded Area Used for Disposal of Sludge from a Water Treatment Plant

    Directory of Open Access Journals (Sweden)

    Ricardo Cosme Arraes Moreira

    2011-01-01

    Full Text Available The effects of disposal of sludge from water treatment plant (WTS in area damaged by laterite extraction and its consequences to soil and groundwater were investigated. Therefore, the presence and concentration of anthropogenic elements and chemical compounds were determinated. WTS disposal's influence was characterized by electroresistivity method. The WTS's geochemical dispersion was noticed in the first meters of the nonsaturated zone from the lending area. Lateritic profiles were characterized due to the large variation in chemical composition between the horizons. Infiltration and percolation of rainwater through the WTS have caused migration of total dissolved solids to the groundwater. WTS's disposing area has more similarities to local preserved vegetation than to gravel bed area. WTS can be considered a noninert residue if disposed in degraded areas located in regions with similar geological and hydrochemical characteristics.

  6. Microwave and thermal pretreatment as methods for increasing the biogas potential of secondary sludge from municipal wastewater treatment plants

    DEFF Research Database (Denmark)

    Kuglarz, Mariusz; Karakashev, Dimitar Borisov; Angelidaki, Irini

    2013-01-01

    In the present study, the sludge was pretreated with microwave irradiation and low-temperature thermal method, both conducted under the same temperature range (30–100°C). Microwave pretreatment was found to be superior over the thermal treatment with respect to sludge solubilization and biogas pr...... experiments indicated that pre-treated sludge (microwave irradiation: 900W, temperature: 60–70°C) gave 35% more methane, compared to untreated sludge. Moreover, the results of this study clearly demonstrated that microwave pretreated sludge showed better degree of sanitation....

  7. Studies and research concerning BNFP: spent fuel dry storage studies at the Barnwell Nuclear Fuel Plant

    International Nuclear Information System (INIS)

    Anderson, K.J.

    1980-09-01

    Conceptual designs are presented utilizing the Barnwell Nuclear Fuel Plant for the dry interim storage of spent light water reactor fuel. Studies were conducted to determine feasible approaches to storing spent fuel by methods other than wet pool storage. Fuel that has had an opportunity to cool for several years, or more, after discharge from a reactor is especially adaptable to dry storage since its thermal load is greatly reduced compared to the thermal load immediately following discharge. A thermal analysis was performed to help in determining the feasibility of various spent fuel dry storage concepts. Methods to reject the heat from dry storage are briefly discussed, which include both active and passive cooling systems. The storage modes reviewed include above and below ground caisson-type storage facilities and numerous variations of vault, or hot cell-type, storage facilities

  8. Emulsion type dry cleaning system for reduction of laundry drains in nuclear plants

    International Nuclear Information System (INIS)

    Kohanawa, O.; Matsumoto, H.

    1987-01-01

    Protective clothing against radioactive contamination used in the radiation controlled areas of nuclear plants has been washed by the same wet washing as used for underwear washing, but recently dry cleaning is coming into use in place of wet washing, which generates a large quantity of laundry drain. However, it was required to use wet washing once every five to ten dry cleanings for washing protective clothing, because conventional dry cleaning is less effective in removing water-soluble soils. Therefore, in order to eliminate wet washing, and to decrease the quantity of laundry drains, the emulsion type dry cleaning system capable of removing both oil-soluble and water-soluble soils at a time has been developed. The results of developmental experiments and actual application are presented in this paper

  9. Measurement of symbiotic nitrogen-fixation in leguminous host-plants grown in heavy metal-contaminated soils amended with sewage sludge.

    Science.gov (United States)

    Obbard, J P; Jones, K C

    2001-01-01

    Rates of nitrogen fixation by Rhizobium in symbiosis with leguminous host-plants including white clover, broad bean and peas have been established in soils that have been amended experimentally with heavy metal-contaminated sewage sludges. Results from 15N-dilution experiments for the measurement of N2 fixation have shown that adverse heavy metal effects are apparent on symbiotic N2 fixation rates for white clover grown in inter-specific competition with ryegrass under mixed sward conditions, compared to white clover grown in pure sward. Further experiments on broad bean and pea indicated a significant, but minor-inhibitory metal-related effect on the rate of N2 fixation compared to untreated soils and soils amended with a relatively uncontaminated sludge. The implications of the results with respect to sludge utilisation in agriculture are discussed.

  10. Biomass and diversity of dry alpine plant communities along altitudinal gradients in the Himalayas

    NARCIS (Netherlands)

    Namgail, T.; Rawat, G.S.; Mishra, C.; Wieren, van S.E.; Prins, H.H.T.

    2012-01-01

    A non-linear relationship between phytodiversity and altitude has widely been reported, but the relationship between phytomass and altitude remains little understood.We examined the phytomass and diversity of vascular plants along altitudinal gradients on the dry alpine rangelands of Ladakh, western

  11. Effects of Seed Proportion and Planting Pattern on Dry Matter Yield ...

    African Journals Online (AJOL)

    Panicum coloratum (PC) and Stylosanthes guianensis (SG) mixed pasture was established to assess the effect of seed proportion and planting pattern on Dry Matter Yield (DMY), compatibility and nutrient content of the mixed stand. Seeds of PC and SG were mixed as 50%PC+50% SG and 25% PC+75% SG and sown in ...

  12. Plant diversity patterns in neotropical dry forests and their conservation implications

    Science.gov (United States)

    K. Banda-R; A. Delgado-Salinas; K. G. Dexter; R. Linares-Palomino; A. Oliveira-Filho; D. Prado; M. Pullan; C. Quintana; R. Riina; G. M. Rodriguez M.; J. Weintritt; P. Acevedo-Rodriguez; J. Adarve; E. Alvarez; A. Aranguren B.; J. C. Arteaga; G. Aymard; A. Castano; N. Ceballos-Mago; A. Cogollo; H. Cuadros; F. Delgado; W. Devia; H. Duenas; L. Fajardo; A. Fernandez; M. A. Fernandez; J. Franklin; E. H. Freid; L. A. Galetti; R. Gonto; R. Gonzalez-M.; R. Graveson; E. H. Helmer; A. Idarraga; R. Lopez; H. Marcano-Vega; O. G. Martinez; H. M. Maturo; M. McDonald; K. McLaren; O. Melo; F. Mijares; V. Mogni; D. Molina; N. d. P. Moreno; J. M. Nassar; D. M. Neves; L. J. Oakley; M. Oatham; A. R. Olvera-Luna; F. F. Pezzini; O. J. R. Dominguez; M. E. Rios; O. Rivera; N. Rodriguez; A. Rojas; T. Sarkinen; R. Sanchez; M. Smith; C. Vargas; B. Villanueva; R. T. Pennington

    2016-01-01

    Seasonally dry tropical forests are distributed across Latin America and the Caribbean and are highly threatened, with less than 10% of their original extent remaining in many countries. Using 835 inventories covering 4660 species of woody plants, we show marked floristic turnover among inventories and regions, which may be higher than...

  13. Techno-economic assessment of biogas plant upgrading by adsorption of hydrogen sulfide on treated sewage–sludge

    International Nuclear Information System (INIS)

    Aguilera, P.G.; Gutiérrez Ortiz, F.J.

    2016-01-01

    Highlights: • Three processes were considered: desulfurization by adsorption, in-situ sorbent regeneration and its production. • The steam for regeneration was studied considering it as a bought external utility and as an in-situ produced utility. • From the cash flow analysis, the cost of the overall desulfurization process was between 2.5 and 4.0 c€/Nm 3 . • A sensitivity analysis was carried out to consider the uncertainty of the methodology. • The competitiveness of the technology seems to be promising versus other biogas H 2 S removal technologies. - Abstract: Biogas plant upgrading by adsorption of hydrogen sulfide on treated sewage–sludge was techno-economically assessed. Three different processes were included in the study: the desulfurization of biogas by adsorption, the in-situ regeneration of the adsorbent and its production from sewage-sludge. Biogas plant upgrading was performed for a flow rate of 1000 Nm 3 /h of biogas with a H 2 S concentration of 2000 ppmv and a breakthrough concentration of 200 ppmv, which is the technical limit value for internal combustion engines. The cost due to the steam required for the in-situ regeneration was evaluated in two different scenarios: as a bought external utility and as an in-situ produced utility, installing an electric or a biogas steam boiler. According to the cash flow analysis carried out, all the options require a similar minimum selling price for the upgraded biogas (about 0.27–0.29 €/Nm 3 ), with a cost of the overall desulfurization process between 2.5 and 4.0 c€/Nm 3 .

  14. Correlating microbial community compositions with environmental factors in activated sludge from four full-scale municipal wastewater treatment plants in Shanghai, China.

    Science.gov (United States)

    Gao, Pin; Xu, Wenli; Sontag, Philip; Li, Xiang; Xue, Gang; Liu, Tong; Sun, Weimin

    2016-05-01

    Activated sludge system is an important process of domestic and industrial wastewater treatment containing highly diverse microbial communities. In this study, high-throughput sequencing was applied to examine the microbial community composition and diversity of activated sludge samples from four full-scale municipal wastewater treatment plants (WWTPs) in Shanghai. A relationship between microbial communities and environmental variables was examined. Proteobacteria was the most dominant phylogenetic group, followed by Bacteroidetes and Firmicutes. A total of 166 genera were commonly shared by all seven sludge samples, including Zoogloea, Dechloromonas, Thauera, Nitrospira, Arcobacter, etc. Besides these shared populations, certain unique bacterial populations were found abundant in individual sludge sample. Canonical correspondence analysis (CCA) indicated that influent COD and pH had the greatest influence on microbial community compositions, whereas dissolved oxygen (DO) exhibited the least influence. The operating process was likely to foster diversity of the microbial communities inhabiting the wastewater treatment facilities. Alternative operation methods including a fluctuation of anoxic, oxic, and anaerobic conditions were favorable for promoting the growth of diverse microbial populations in activated sludge systems.

  15. Production of dry wood chips in connection with a district heating plant

    Directory of Open Access Journals (Sweden)

    Yrjölä Jukka

    2004-01-01

    Full Text Available Moisture and its variation in wood chips make the control of burning in small scale heating appliances difficult resulting in emissions and loss of efficiency. If the quality of wood chips would be better, i. e. dried and sieved fuel with more uniform size distribution would be avail able, the burning could be much cleaner and efficiency higher. In addition higher power out put could be obtained and the investment costs of the burning appliances would be lower. The production of sieved and dried wood chip with good quality could be accomplished in connection with a district heating plant. Then the plant would make profit, in addition to the district heat, from the dried wood chips sold to the neighboring buildings and enterprises sep a rated from the district heating net using wood chips in energy production. The peak power of a district heating plant is required only a short time during the coldest days of the winter. Then the excess capacity during the milder days can be used as heat source for drying of wood chips to be marketed. Then wood chips are sieved and the fuel with best quality is sold and the reject is used as fuel in the plant it self. In a larger district heating plant, quality of the fuel does not need to be so high In this paper the effect of moisture on the fuel chain and on the boiler is discussed. Energy and mass balance calculations as a tool of system design is described and the characteristics of proposed dry chips production method is discussed.

  16. Modelagem do processo de desidratação de lodo anaeróbio em leitos de secagem simulados Anaerobic sludge dewatering process modeling in simulated drying beds

    Directory of Open Access Journals (Sweden)

    Sérgio R. A. Soares

    2001-05-01

    Full Text Available O emprego de leitos de secagem para a desidratação de lodo de descarte de reatores UASB, constitui excelente alternativa, face a sua simplicidade operacional e aos reduzidos custos de implantação. Este trabalho apresenta uma análise dos fenômenos que influenciam o processo de desidratação de lodo anaeróbio, a partir de simulação de leitos de secagem. Neste sentido, são feitas considerações sobre as características e o comportamento do lodo durante cada fase da secagem. Sugere-se também, um modelo matemático para representar o processo de secagem, obtido a partir dos dados experimentais.The employment of drying beds is an excellent option for dewatering of UASB reactor discarded sludge, because of their simple operation and low construction costs. This paper presents an anaerobic sludge dewatering process analysis of the most influential phenomenon based on drying beds simulation. Therefore, some considerations were made about sludge characteristics and behavior during each dewatering stage. A mathematical model for dewatering process representation obtained from experimental data is also suggested.

  17. Assessment of heavy metal pollution with applications of sewage sludge and city compost for maximizing crop yields

    International Nuclear Information System (INIS)

    D'Souza, T.J.; Ramachandran, V.; Raghu, K.

    1997-01-01

    Land application of municipal sewage sludge and city compost as organic manures make it imperative to assess heavy-metal pollution in soils and crops. Greenhouse experiments, conducted on maize in a vertisol and an ultisol amended with various doses of dry sewage sludge and city compost from Mumbai, indicated significant increases in dry matter-yields only in the vertisol. Significantly higher concentrations of Zn, Cu, Co, Pb, Ni and Cd were obtained in plants grown in the amended ultisol, but not in the amended vertisol. As Cd is the most toxic, experiments were conducted with four contrasting soils amended with varying doses of Cd-enriched sewage sludge and city compost. Results showed significant reductions in dry-matter yields of maize shoots at the higher rates of sludge or compost in the ultisol and an alfisol, but with no significant effects in the vertisol or an entisol. The levels of Cd and Zn were significantly elevated in plants in all four soil types. There were negative residual effects from the sludge and compost amendments: dry-matter yields of a succeeding maize crop were decreased in the ultisol and alfisol. Experiments with soils amended with sludge enriched with either Cd or Zn at 80 mg kg -1 indicated significant reductions in dry matter in all soils with Cd, but not with Zn. The results demonstrate that sewage sludges and city composts may be effectively used for maximizing crop yields, especially in vertisols and entisols. However, caution has to be exercised when using sludges containing even relatively low levels of Cd, or high levels of Zn, depending upon soil type. (author)

  18. Combined cycle power plant with indirect dry cooling tower forecasting using artificial neural network

    Directory of Open Access Journals (Sweden)

    Asad Dehghani Samani

    2017-07-01

    Full Text Available Application of Artificial Neural Network (ANN in modeling of combined cycle power plant (CCPP with dry cooling tower (Heller tower has been investigated in this paper. Prediction of power plant output (megawatt under different working conditions was made using multi-layer feed-forward ANN and training was performed with operational data using back-propagation. Two ANN network was constructed for the steam turbine (ST and the main cooling system(MCS. Results indicate that the ANN model is effective in predicting the power plant output with good accuracy.

  19. Dry anaerobic co-digestion of organic fraction of municipal waste with paperboard mill sludge and gelatin solid waste for enhancement of hydrogen production.

    Science.gov (United States)

    Elsamadony, M; Tawfik, A

    2015-09-01

    The aim of this study is to investigate the bio-H2 production via dry anaerobic co-fermentation of organic fraction of municipal solid waste (OFMSW) with protein and calcium-rich substrates such as gelatin solid waste (GSW) and paperboard mill sludge (PMS). Co-fermentation of OFMSW/GSW/PMS significantly enhanced the H2 production (HP) and H2 yield (HY). The maximum HP of 1082.5±91.4 mL and HY of 144.9±9.8 mL/gVSremoved were achieved at a volumetric ratio of 70% OFMSW:20% GSW:10% PMS. COD, carbohydrate, protein and lipids conversion efficiencies were 60.9±4.4%, 71.4±3.5%, 22.6±2.3% and 20.5±1.8% respectively. Co-fermentation process reduced the particle size distribution which is favorably utilized by hydrogen producing bacteria. The mean particle size diameters for feedstock and the digestate were 939.3 and 115.2μm, respectively with reduction value of 8.15-fold in the mixtures. The volumetric H2 production increased from 4.5±0.3 to 7.2±0.6 L(H2)/L(substrate) at increasing Ca(+2) concentrations from 1.8±0.1 to 6.3±0.5 g/L respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Byproducts Utilization Program: Sewage Sludge Irradiation Project. Progress report, July-December 1983

    Energy Technology Data Exchange (ETDEWEB)

    1984-12-01

    Engineering support for a demonstration-scale irradiator design included assisting the City of Albuquerque in preparing a comprehensive site plan for their proposed sludge handling and treatment facilities. The solar sludge dryer has been delivered to SNLA. A preliminary sludge drying experiment indicated the importance of optimizing stirring and air flow. Installation of instrumentation and mechanical equipment continued. The Sandia Irradiator for Dried Sewage Solids (SIDSS) was used to irradiate 23 tons of dried, digested sewage sludge for the New Mexico State University (NMSU) Department of Crop and Soil Sciences. Gamma Irradiation Facility (GIF) operations included irradiation of ground pork for Toxoplasma gondii inactivation experiments, irradiation of surgical supplies and soil samples. Beneficial Uses Shipping Systems (BUSS) cask activities included near completion of the two full-scale cask bodies. Work continued on the Cask Safety Analysis Report (SAR) including additional analyses to reconfigure the six strontium fluoride capsules and/or reduce the number of capsules accommodated. NMSU has indicated no regrowth of salmonellae occurred in the irradiated sludge stockpile, while salmonellae did regrow in the unirradiated stockpile. Analyses of raw and digested sewage sludge from the Albuquerque Waste Water Treatment Plant showed levels of Yersinia enterocolitica (a human pathogen of emerging significance) to be below detection limits.

  1. Byproducts Utilization Program: Sewage Sludge Irradiation Project. Progress report, July-December 1983

    International Nuclear Information System (INIS)

    1984-12-01

    Engineering support for a demonstration-scale irradiator design included assisting the City of Albuquerque in preparing a comprehensive site plan for their proposed sludge handling and treatment facilities. The solar sludge dryer has been delivered to SNLA. A preliminary sludge drying experiment indicated the importance of optimizing stirring and air flow. Installation of instrumentation and mechanical equipment continued. The Sandia Irradiator for Dried Sewage Solids (SIDSS) was used to irradiate 23 tons of dried, digested sewage sludge for the New Mexico State University (NMSU) Department of Crop and Soil Sciences. Gamma Irradiation Facility (GIF) operations included irradiation of ground pork for Toxoplasma gondii inactivation experiments, irradiation of surgical supplies and soil samples. Beneficial Uses Shipping Systems (BUSS) cask activities included near completion of the two full-scale cask bodies. Work continued on the Cask Safety Analysis Report (SAR) including additional analyses to reconfigure the six strontium fluoride capsules and/or reduce the number of capsules accommodated. NMSU has indicated no regrowth of salmonellae occurred in the irradiated sludge stockpile, while salmonellae did regrow in the unirradiated stockpile. Analyses of raw and digested sewage sludge from the Albuquerque Waste Water Treatment Plant showed levels of Yersinia enterocolitica (a human pathogen of emerging significance) to be below detection limits

  2. Occurrence of hexabromocyclododecane (HBCD) in sewage sludge from Shanghai: implications for source and environmental burden.

    Science.gov (United States)

    Xiang, Nan; Chen, Ling; Meng, Xiang-Zhou; Dai, Xiaohu

    2015-01-01

    Sewage sludge is regarded as one important sink for hydrophobic pollutants, including hexabromocyclododecane (HBCD), but the current pollution situation of HBCD in sludge from China is unknown, despite that many studies have reported its occurrence in other environmental compartments across China. In this study, we collected 27 sludge samples from Shanghai to investigate the occurrence and distribution, to examine the diastereoisomer profile and sources, and to provide advice for future pollution control. HBCD is ubiquitous in sludge with a mean concentration of 4.7ngg(-1) dry weight (dw) (range: 0.10-37.2ngg(-1) dw), lower than data from European countries and the United States. Sludge from wastewater treatment plants (WWTPs) treating industrial wastewater contained high levels of HBCD. However, no significant relationships were found between HBCD and four parameters (total organic carbon, the percentage of industrial wastewater, capacity and sludge production of WWTPs). α- and γ-HBCD were two main components with the corresponding contributions of 47.9% and 48.0%. Comparing with the annual production of HBCD in China, its storage in sewage sludge is extremely low (less than 0.002%), indicating future release of HBCD from waste polystyrene foam will be significant, and careful considerations should be taken during waste disposal. To our knowledge, this is the first report on HBCD in sewage sludge from China. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Influence of Cultivar and Planting Material on Soluble Dry Matter Content of Dahlia Tubers

    Directory of Open Access Journals (Sweden)

    Ioana Ciobanu

    2016-11-01

    Full Text Available The aim of present paper was to study the influence ofthe planting material (forced and unforced tuberous roots, and of the cultivar on the average soluble dry matter content (% from Dahlia tuberous roots at harvest. Also, there were determined a series of relationships between soluble dry matter content and main plant characteristics, like average shoots per plant and average weight of the tuberous roots at harvesting. The study was conducted for two years at University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca on seven cultivars of Dahlia variabilis ‘cactus’ type: 'Kennemerland', 'TsukiYori No Sisha', 'Hayley Jane', 'Purple Gem', 'Star Favourite', 'Park Princess' and 'Friquolet'. Based on the results obtained it can be concluded that the forcing of the tuberous roots affected the accumulation of soluble dry matter content at dahlia tubers, but it also depends on the cultivar. The highest content of soluble dry matter was at following cultivars 'Star Favourite'/forced tubers (25.47%, 'TsukiYori No Sisha'/unforced tubers (24.80%, ‘Kennemerland’/unforced tubers (24.27%, 'Hayley Jane'/forced tubers (23.97%, and 'TsukiYori No Sisha'/forced tubers (22.57%. These dahlia cultivars can be recommended for inulin extraction.

  4. Sterilization of activated sludges by gamma radiations

    International Nuclear Information System (INIS)

    Lacroix, J.P.; Boland, M.

    1978-01-01

    The purification process of a wastewater is described. It has been found that the great amount of sludge produced, the average value being 50 g of dry matter per inhabitant and per day, contains three species of pathogen microorganims: enteroviruses, bacteria and parasite eggs and cystes and that this microbial pollution is extremely harmful to human health. Therefore in order to manipulate as well as to use activated sludges in an agriculturad soil, a strong action against pathogen microorganisms is to be taken. Various treatment of sterilization are then described such as: pasteurization, incineration, liming, composting and by gamma radiations. The treatment by gamma radiations has been found to have many advantages in comparison with the other ones. An example of a sterilization plant located in Western Germany is given. (G.C.)

  5. Tsukamurella spumae sp. nov., a novel actinomycete associated with foaming in activated sludge plants.

    Science.gov (United States)

    Nam, Sun-Woo; Chun, Jongsik; Kim, Seungbum; Kim, Wonyong; Zakrzewska-Czerwinska, Jolanta; Goodfellow, Michael

    2003-09-01

    A polyphasic taxonomic study was undertaken to establish the taxonomic position of six representative strains isolated from activated sewage sludge foam. The organisms were found to have chemical and morphological properties consistent with their assignment to the genus Tsukamurella. DNA:DNA relatedness studies showed that five out of the six isolates formed a distinct genomic species, the remaining strain was most closely associated with this taxon. The five isolates had a unique phenotypic profile that served to distinguish them from representatives of the validly described species of Tsukamurella. The combination of the genotypic and phenotypic data indicated that the five strains should be classified as a new species in the genus Tsukamurella. The name proposed for this taxon is Tsukamurella spumae, the type strain is N1171T (= DSM 44.113T = NCIMB 13947T). It was also shown that some of the reference strains were misclassified as Tsukamurella paurometabola.

  6. Presence of helminth eggs in wastewater sludge; Presencia de huevos de helmintos en fangos de depuracion de aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    GeovanPerez Ortiz, O. G.; Gomez Vera, D. [Estacion Depuradora de Aguas Residuales. Alboraia. Valencia (Spain); Faubell Brell, M. [Universidad de Valencia (Spain); Morenilla Martinez, J. J.; Bernacer Bonora, I. [Entididad Publica de Saneamiento. Valencia (Spain); Bernabeu Adrian, A. [S. A. Agricultures de la Vega. Valencia (Spain); Amores Blasco, S. [Depuracion de Aguas del Mediterraneo. Valencia (Spain)

    2000-07-01

    Land application is one of the best options for the elimination of wastewater sludge, because sludge is useful as conditioner and fertilizer in soils. However, land application represents a sanitary hazards due to the sludge's content in pathogenic agents. Helminth eggs are among these agents, and their hardness and resistance to adverse environmental conditions allows them to survive in soils for months. With this in mind, we have launched a study of the presence of helminth eggs in the sludge of a wastewater treatment plant in Alboraia (Valencia). The results show a concentration of helminth eggs in digestion sludge of 27.000 eggs/kg dry matter. We discuss the potential sanitary relevant of these results and the need to continue with this evaluation program. (Author) 20 refs.

  7. Irradiation of sewage sludge using cesium-137: a comparative assessment

    International Nuclear Information System (INIS)

    1980-06-01

    Irradiation using 137 CS is a recently developed process for disinfecting sewage sludge before applying it to the land. Irradiation, composting, and heat drying are Processes to Further Reduce Pathogens (PFRP) when operated to meet the guidelines set forth under Title 40, Code of the Federal Register, Part 257 (40 CFR 257). This report identifies and develops technical, operational, and environmental considerations for sludge handling systems incorporating these PFRP to determine the economic advantages of each process. The results indicate that sludge irradiation systems are cost-competitive with composting and heat drying systems for wastewater treatment plants with or without existing anaerobic digesters. Irradiation can thus be considered for new as well as upgrading existing facilities for sludge disinfection. An attractive aspect of the irradiation process is that significantly less conventional energy is used for operation when compared to composting and heat drying. In the final analysis, however, the applicability and desirability of any process is best determined by more evaluations specific to a given community

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

    International Nuclear Information System (INIS)

    Parish, K.J.; Applegate, D.V.; Postlethwait, P.D.; Boparai, A.S.; Reedy, G.T.

    1994-12-01

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

  9. Nitrogen concentration in dry matter of the fifth leaf during growth of greenhouse tomato plants

    Directory of Open Access Journals (Sweden)

    Rattin Jorge E.

    2002-01-01

    Full Text Available The nitrogen concentration in dry matter of the fifth leaf during growth of a greenhouse tomato crop was determined. Plants of hybrid Monte Carlo were grown in 4.5 L bags, using a commercial substrate, in a plant density of 3.3 plants m-2. A nutrient solution containing, in mmol L-1: KNO3, 4.0; K2SO4, 0.9; Ca(NO32, 3.75; KH2PO4, 1.5; MgSO4, 1.0; iron chelate 19. 10³, was used as reference. Microelements were added by a commercial mixture. The T3 treatment was equal to the reference nutrient solution, whereas in treatments T1, T2, T4 and T5 quantities of all nutrients from T3 were multiplied by 0.25, 0.50, 1.25 and 1.50, respectively. In each treatment, the volume of 1 L of nutrient solution was supplied to each plant once a week by fertigation. Periodically destructive measurements were made from anthesis to ripening of the first truss, to determine dry matter and N concentration in shoot and in fifth leaf tissues, counted from the apex to the bottom of the plant. Five dilution curves were fitted from data of N concentration in the fifth leaf and shoot dry matter accumulation during growth of plants. A general relationship was adjusted between actual N concentration in shoot (Nt and in the fifth leaf (Nf: Nt = 1.287 Nf (R² = 0.80. This relationship could be used to estimate the N status of plants by means of a nitrogen nutrition index (NNI, from analysis of the fifth leaf sap.

  10. Phytoextraction of heavy metals from municipal sewage sludge by Rosa multiflora and Sida hermaphrodita.

    Science.gov (United States)

    Antonkiewicz, Jacek; Kołodziej, Barbara; Bielińska, Elżbieta Jolanta

    2017-04-03

    The aim of the study was to evaluate the efficacy of the multiflora rose var. "Jatar" (Rosa multiflora Thunb. ex Murray) and the Virginia fanpetals (Sida hermaphrodita Rusby) to phytoextract heavy metals from municipal sewage sludge. The 6-year field experiment involved four levels of fertilization with sewage sludge at doses of 0, 10, 20, 40, and 60 Mg DM (Dry Mass) sludge ha -1 . The increasing doses of sewage sludge were found to significantly increase the yield of multiflora rose and Virginia fanpetals biomass. They also significantly increased the content of heavy metals in these plants. The highest uptake of heavy metals by the multiflora rose and Virginia fanpetals crops was recorded at the fertilization dose of 60 Mg DM ⋅ ha -1 . Our investigations show that the Virginia fanpetals was more efficient in the phytoextraction of Cr, Ni, Cu, Zn, and Cd from the sewage sludge than the multiflora rose, due to the greater yields and higher heavy metal uptake by the former plant. In turn, the multiflora rose phytoextracted greater amounts of Pb from the sewage sludge. The analyses indicate that the Virginia fanpetals can be used for phytoremediation (phytoextraction) of heavy metals contained in sewage sludge.

  11. Abandoned coal mining sites: using ecotoxicological tests to support an industrial organic sludge amendment.

    Science.gov (United States)

    Chiochetta, Claudete G; Radetski, Marilice R; Corrêa, Albertina X R; Tischer, Vinícius; Tiepo, Erasmo N; Radetski, Claudemir M

    2013-11-01

    The different stages involved in coal mining-related activities result in a degraded landscape and sites associated with large amounts of dumped waste material. Remediation of these contaminated soils can be carried out by application of industrial organic sludge if the concerns regarding the potential negative environmental impacts of this experimental practice are properly addressed. In this context, the objective of this study was to use ecotoxicological tests to determine the quantity of organic industrial sludge that is required as a soil amendment to restore soil production while avoiding environmental impact. Chemical analysis of the solids (industrial sludge and soil) and their leachates was carried out as well as a battery of ecotoxicity tests on enzymes (hydrolytic activity), bacteria, algae, daphnids, earthworms, and higher plants, according to standardized methodologies. Solid and leachate samples of coal-contaminated soil were more toxic than those of industrial sludge towards enzyme activity, bacteria, algae, daphnids, and earthworms. In the case of the higher plants (lettuce, corn, wild cabbage, and Surinam cherry) the industrial sludge was more toxic than the coal-contaminated soil, and a soil/sludge mixture (66:34% dry weight basis) had a stimulatory effect on the Surinam cherry biomass. The ecotoxicological assessment of the coal-contaminated soil remediation using sludge as an amendment is very important to determine application rates that could promote a stimulatory effect on agronomic species without negatively affecting the environment.

  12. Use of biogas for cogeneration of heat and electricity for local application: performance evaluation of an engine power generator and a sludge thermal dryer.

    Science.gov (United States)

    Lobato, L C S; Chernicharo, C A L; Pujatti, F J P; Martins, O M; Melo, G C B; Recio, A A R

    2013-01-01

    A small unit of cogeneration of energy and heat was tested at the Centre for Research and Training on Sanitation UFMG/COPASA - CePTS, located at the Arrudas Sewage Treatment Plant, in Belo Horizonte, Minas Gerais, Brazil. The unit consisted of an engine power generator adapted to run on biogas, a thermal dryer prototype and other peripherals (compressor, biogas storage tank, air blower, etc.). The heat from engine power generator exhaust gases was directed towards the thermal dryer prototype to dry the sludge and disinfect it. The results showed that the experimental apparatus is self-sufficient in electricity, even producing a surplus, available for other uses. The tests of drying and disinfection of sludge lasted 7 h, leading to an increase in solids content from 4 to 8% (50% reduction in sludge volume). Although the drying of sludge was not possible (only thickening was achieved), the disinfection process proved very effective, enabling the complete inactivation of helminth eggs.

  13. Effect of water treatment on the comparative costs of evaporative and dry cooled power plants

    International Nuclear Information System (INIS)

    Gold, H.; Goldstein, D.J.; Yung, D.

    1976-07-01

    The report presents the results of a study on the relative cost of energy from a nominal 1000 Mwe nuclear steam electric generating plant using either dry or evaporative cooling at four sites in the United States: Rochester, New York; Sheridan, Wyoming; Gallup, New Mexico and Dallas, Texas. Previous studies have shown that because of lower efficiencies the total annual evaluated costs for dry cooling systems exceeds the total annual evaluated costs of evaporative cooling systems, not including the cost of water. The cost of water comprises the cost of supplying the makeup water, the cost of treatment of the makeup and/or the circulating water in the tower, and the cost of treatment and disposal of the blowdown in an environmentally acceptable manner. The purpose of the study is to show the effect of water costs on the comparative costs of dry and evaporative cooled towers

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

    Science.gov (United States)

    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.

  15. [Study on the quantitative and qualitative composition of fungi in dried medicinal plants].

    Science.gov (United States)

    Janda, Katarzyna; Ulfig, Krzysztof

    2005-01-01

    The quantitative and qualitative composition of fungi was determined in selected dried medicinal plants purchased in one of the herbal shops in Szczecin, Poland. The samples examined were as follows: chamomile (Flos Chamomillae), peppermint (Folium Menthae piperitae), lemon balm (Folium Melissae), St. John's wort (Herba Hyperici), and two herbal mixtures. The fungal composition depended on the specified sample. Xerophilic fungi, i.e. Eurotium amstelodami, E. herbariorum, E. rubrum and Wallemia sebi were isolated from dried medicinal plants. E. amstelodami was the predominating species. The prevailing thermophilic and thermotolerant species were Rhizopus microsporus var. rhizopodiformis and Aspergillus fumigatus. Pink and white yeasts were also numerous in some samples. Except for Aspergillus niger, mesophilic and toxigenous species were found to occur infrequently in the samples. However, Aspergillus versicolor was found to occur abundantly in lemon balm.

  16. Improved waste-activated sludge dewatering using sludge/oil ...

    African Journals Online (AJOL)

    Ultrasonication had low dewatering and energy efficiency with long irradiation times, indicating that it would be difficult to implement in a field plant. The water content of sludge was reduced to 60% within 120 s using microwaves, but dewatering efficiency depended on the thickness and volume of the sludge. In a pilot-scale ...

  17. Natural draft dry-type cooling tower for steam power plants

    International Nuclear Information System (INIS)

    Nasser, G.

    1976-01-01

    The task to build natural-draught dry cooling towers for large steam power plants as simple, compact, and economical as possible may be achieved by a combination of known features with the aid of the present application: the condenser elements built as piles of corrugated plates are arranged in the form of a truncated pyramid widened towards the top. For the cooling-air flow inlet openings for hot gas supplied from the lower part of the dome are provided. (UWI) [de

  18. Catalytic dry reforming of waste plastics from different waste treatment plants for production of synthesis gases.

    Science.gov (United States)

    Saad, Juniza Md; Williams, Paul T

    2016-12-01

    Catalytic dry reforming of mixed waste plastics, from a range of different municipal, commercial and industrial sources, were processed in a two-stage fixed bed reactor. Pyrolysis of the plastics took place in the first stage and dry (CO 2 ) reforming of the evolved pyrolysis gases took place in the second stage in the presence of Ni/Al 2 O 3 and Ni-Co/Al 2 O 3 catalysts in order to improve the production of syngas from the dry reforming process. The results showed that the highest amount of syngas yield was obtained from the dry reforming of plastic waste from the agricultural industry with the Ni/Al 2 O 3 catalyst, producing 153.67mmol syngas g -1 waste . The addition of cobalt metal as a promoter to the Ni/Al 2 O 3 catalyst did not have a major influence on syngas yield. Overall, the catalytic-dry reforming of waste plastics from various waste treatment plants showed great potential towards the production of synthesis gases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Insecticidal and biochemical effect of some dried plants against Oryzaephilus surinamensis (Coleoptera-Silvanidae

    Directory of Open Access Journals (Sweden)

    A.M. Al Qahtani

    2012-01-01

    Full Text Available Dry powders of three plants, namely ginger (Zingiber afficinale, hail (Elettaria cardamomum and shammar (Foeniculum vulgare were tested, for their toxicity, against the adult beetle Oryzaephilus surinamensis, as date pest threatens the date product in Saudi Arabia. All the tested plants showed insecticidal activity against O. surinamensis. Ginger is the most potent plant, recording the lowest LC50 value (0.14 mg/g followed by hail and shammar (LC50 = 0.4 and 0.7 mg/g respectively. Tested plants alter the protein configuration of O. surinamensis after using PAGE for protein analysis. Ginger and shammar increased the insect protein subfractions than normal; while hail reduced separated bands, especially proteins of moderate molecular weight.

  20. Performance Analysis of an Updraft Tower System for Dry Cooling in Large-Scale Power Plants

    Directory of Open Access Journals (Sweden)

    Haotian Liu

    2017-11-01

    Full Text Available An updraft tower cooling system is assessed for elimination of water use associated with power plant heat rejection. Heat rejected from the power plant condenser is used to warm the air at the base of an updraft tower; buoyancy-driven air flows through a recuperative turbine inside the tower. The secondary loop, which couples the power plant condenser to a heat exchanger at the tower base, can be configured either as a constant-pressure pump cycle or a vapor compression cycle. The novel use of a compressor can elevate the air temperature in the tower base to increases the turbine power recovery and decrease the power plant condensing temperature. The system feasibility is evaluated by comparing the net power needed to operate the system versus alternative dry cooling schemes. A thermodynamic model coupling all system components is developed for parametric studies and system performance evaluation. The model predicts that constant-pressure pump cycle consumes less power than using a compressor; the extra compression power required for temperature lift is much larger than the gain in turbine power output. The updraft tower system with a pumped secondary loop can allow dry cooling with less power plant efficiency penalty compared to air-cooled condensers.

  1. An Economic comparison of sludge irradiation and alternative methods of municipal sludge treatment

    Energy Technology Data Exchange (ETDEWEB)

    Ahlstrom, S.B.; McGuire, H.E.

    1977-11-01

    The relative economics of radiation treatment and other sludge treatment processes are reported. The desirability of radiation treatment is assessed in terms of cost and the quality of the treated sludge product. The major conclusions of this study are: radiation treatment is a high-level disinfection process. Therefore, it should only be considered if high levels of disinfection are required for widespread reuse of the sludge; the handling, transporting and pathogen growback problems associated with disinfected wet sludge makes it less attractive for reuse than dry sludge; radiation of composted sludge produces a product of similar quality at less cost than any thermal treatment and/or flash drying treatment option for situations where a high degree of disinfection is required; and heavy metal concerns, especially cadmium, may limit the reuse of sludge despite high disinfection levels. It is recommended that radiation treatment of sludge, particularly dry sludge, continue to be studied. A sensitivity analysis investigating the optimal conditions under which sludge irradiation operates should be instigated. Furthermore, costs of adding sludge irradiation to existing sludge treatment schemes should be determined.

  2. Economic comparison of sludge irradiation and alternative methods of municipal sludge treatment

    International Nuclear Information System (INIS)

    Ahlstrom, S.B.; McGuire, H.E.

    1977-11-01

    The relative economics of radiation treatment and other sludge treatment processes are reported. The desirability of radiation treatment is assessed in terms of cost and the quality of the treated sludge product. The major conclusions of this study are: radiation treatment is a high-level disinfection process. Therefore, it should only be considered if high levels of disinfection are required for widespread reuse of the sludge; the handling, transporting and pathogen growback problems associated with disinfected wet sludge makes it less attractive for reuse than dry sludge; radiation of composted sludge produces a product of similar quality at less cost than any thermal treatment and/or flash drying treatment option for situations where a high degree of disinfection is required; and heavy metal concerns, especially cadmium, may limit the reuse of sludge despite high disinfection levels. It is recommended that radiation treatment of sludge, particularly dry sludge, continue to be studied. A sensitivity analysis investigating the optimal conditions under which sludge irradiation operates should be instigated. Furthermore, costs of adding sludge irradiation to existing sludge treatment schemes should be determined

  3. Minimization of Excess Sludge in Activated Sludge Systems

    Directory of Open Access Journals (Sweden)

    Sayed Ali Reza Momeni

    2006-01-01

    Full Text Available The disposal of excess sludge from wastewater treatment plant represents a rising challenge in activated sludge processes. Hence, the minimization of excess sludge production was investigated by increasing the dissolved oxygen in aeration basin. Units of the pilot include: Primary sedimentation tank, aeration basin, secondary sedimentation tank, and return sludge tank. Volume of aeration basin is 360 l and influent flow rate is 90 L/h. Influent of pilot is taken from effluent of grit chamber of Isfahan's North Wastewater treatment plant. The experiments were done on different parts of pilot during the 5 month of study. Results show that increase of dissolved oxygen in aeration tank affect on decrease of excess sludge. Increase of dissolved oxygen from 0.5 to 4.5 mg/L resulted in 25% decrease of excess sludge. Variation of dissolved oxygen affect on settleability of sludge too. By increase of dissolved oxygen, SVI decreased and then increased. Value of 1-3 mg/L was the adequate range of dissolved oxygen by settleability of sludge and optimum range was 2-2.5 mg/L. It could be concluded by increasing of dissolved oxygen up to of 3 mg/L, sludge settleability significant decreased.

  4. Operator assisted optimization of sludge dewatering

    DEFF Research Database (Denmark)

    Grüttner, Henrik

    1991-01-01

    On a municipal wastewater treatment plant using a decanter-centrifuge for dewatering of anaerobic digested sludge an operator assisting system for sludge dewatering was developed. The system is based on a database used to collect data on sludge properties and operational conditions which is added...

  5. Including the effects of filamentous bulking sludge during the simulation of wastewater treatment plants using a risk assessment model

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Comas, J.; Rodriquez-Roda, I.

    2009-01-01

    pollution removal efficiency is observed. Also, a scenario analysis is conducted to examine i) the influence of sludge retention time (SRT), the external recirculation flow rate (Qr) and the air flow rate in the bioreactor (modelled as kLa) as factors promoting bulking sludge, and ii) the effect...

  6. Fractionation and business potential from sludge - Pafrak

    Energy Technology Data Exchange (ETDEWEB)

    Kylloenen, H.; Groenroos, A.; Pirkonen, P. (VTT Tecchnical Research Centre of Finland, Jyvaeskylae (Finland)), Email: hanna.kyllonen@vtt.fi; Maekinen, L.; Aemmaelae, A.; Niinimaeki, J. (Univ. of Oulu (Finland)), Email: liisa.makinen@oulu.fi

    2010-10-15

    Wastewater sludges contain valuable components which can be recycled and converted to secondary raw material. High water content of sludge can hinder the further processing. Dry solids content of waste activated sludge after dewatering can be as low as 12-20% and even lower for tertiary sludge. This research aimed with better knowledge of sludge and fractionation to generate potential business ideas, which could lead to new sludge based products and services in national and international markets already in this project or in separate development projects. Primary, waste activated, tertiary and deinking sludge from pulp and paper industry and municipal waste activated sludge were the suspensions to be studied. Basic properties of these sludges have been determined by large number of analysing methods. Wood based components and chemical elements have been determined to clarify the raw material potential for biorefineries. Conventional fractionation techniques (decanter centrifuge, hydrocyclone, belt filter press and sieve bend) have been used to see how the sludge can be fractionated. Correlations of wood based components and dewatering properties have been studied especially for the waste activated sludge. The effects of wood based filter aids were studied on the dewatering properties of waste activated sludge. State of the art has been drawn up about the current utilisation of wastewater sludge. (orig.)

  7. Potential biogas production from sewage sludge: A case study of the sewage treatment plant at Kwame Nkrumah university of science and technology, Ghana

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Richard [Energy Systems Engineering Department, Koforidua Polytechnic, Box KF 981, Koforidua (Ghana); Brew-Hammond, Abeeku [Faculty of Mechanical and Agricultural Engineering, Kwame Nkrumah University of Science and Technology, Private Mail Bag, Kumasi (Ghana)

    2010-07-01

    Biogas generation is one of the most promising renewable energy sources in Ghana. Anaerobic digestion is one of the effective ways of generating biogas. Anaerobic digestion is also a reliable method for wastewater treatment and the digestion the effluent can be used as fertilizer to enhance the fertility of the soil. This paper looks at the possibility of constructing a biogas plant at the KNUST sewage treatment plant tapping its feedstock the sludge at the Primary Sedimentation Tank to generate biogas. A laboratory experiment was done to determine the faecal sludge quality. The flowrate of the sludge was estimated based on the number of times the penstocks (valves) are operated to desludge the sewage which also depends on whether the university is on vacation (35.72 m3/day) or in session (71.44 m3/day). These parameters were used to determine the biogas potential of the sewage using 10, 20 and 30 days retention time for plant sizes of 540 m3, 1100m3 and 1600 m3 respectively. It was estimated that 170,719 m3, 341,858 m3 and 419,458 m3 of methane can be produced in a year and the power production was estimated to be 50 kW, 100 kW and 120 kW for the 540 m3, 1100m3 and 1600 m3 digester sizes respectively.

  8. Drying/rewetting cycles of the soil under alternate partial root-zone drying irrigation reduce carbon and nitrogen retention in the soil-plant systems of potato

    DEFF Research Database (Denmark)

    Sun, Yanqi; Yan, Fei; Liu, Fulai

    2013-01-01

    retention in the soil–plant systems of potato. Potato plants were grown in 20 L split-root pots with three N-fertilization rates, viz., 1.4 (N1), 2.5 (N2), and 4 (N3) g N pot−1 soil, respectively. At tuber initiation and earlier tuber bulking stages, the plants were subjected to PRD and DI treatment......Dry/wet cycles of soil may stimulate mineralization of soil organic carbon (C) and nitrogen (N) leading to increased N bioavailability to plants but potentially also increased C and N losses. We investigated the effects of partial root-zone drying (PRD) and deficit irrigation (DI) on C and N...... for five weeks. For each N rate, the PRD and DI plants received a same amount of water, which allowed re-filling one half of the PRD pots close to full water holding capacity. The results showed that plant dry biomass, plant water use, and water use efficiency were increased with increasing N...

  9. CONSOLIDATION OF K BASIN SLUDGE DATA AND EXPERIENCES ON AGGLOMERATE FORMATION

    International Nuclear Information System (INIS)

    Hill, S.R.

    2010-01-01

    The formation of high sludge strength agglomerates is a key concern to the Sludge Treatment Project (STP) to ensure the sludge can be retrieved after planned storage for up to 10 years in Sludge Transport and Storage Containers (STSC) at T Plant. This report addresses observations of agglomerate formation, conditions that the data shows lead to agglomeration, the frequency of agglomerate formation and postulated physiochemical mechanisms that may lead to agglomeration. Although the exact underlying chemistry of K Basin sludge agglomerate formation is not known, the factors that lead to agglomeration formation, based on observations, are as follows: (1) High Total Uranium Content (i.e., sample homogeneity and influence from other constituents); (2) Distribution of Uranium Phases (i.e., extent of conversion from uraninite to uranium oxide hydroxide compounds); (3) Sample Dry-out (loss of cover water); (4) Elevated temperature; (5) Solubility ofU(IV) phases vs. U(VI) phases; and (6) Long storage times. Agglomerated sludge has occurred infrequently and has only been observed in four laboratory samples, five samples subjected to hydrothermal testing (performed for 7 to 10 hours at ∼185 C and 225 psig), and indirectly during six sampling events in the KE Basin. In the four laboratory samples where agglomerates were observed, the agglomerates exhibited high shear strength and the sample container typically had to be broken to remove the solids. The total uranium content (dry basis) for the four samples (KE Pit, KC-2/3 SS, KC-2/3 M250 and 96-13) were ∼8 wt%, ∼59.0 wt%, 68.3 wt% and 82 wt%. The agglomerates that were present during the six sampling events were undoubtedly disturbed and easily broken apart during sample collection, thus no agglomerates were observed in subsequent laboratory analyses. The highest shear strengths measured for K Basin sludge samples were obtained after hydrothermal treatment (7 to 10 hr at 185 C) of high-uranium-content KE canister sludge

  10. Use of phytoproductivity data in the choice of native plant species to restore a degraded coal mining site amended with a stabilized industrial organic sludge.

    Science.gov (United States)

    Chiochetta, Claudete G; Toumi, Hela; Böhm, Renata F S; Engel, Fernanda; Poyer-Radetski, Gabriel; Rörig, Leonardo R; Adani, Fabrizio; Radetski, Claudemir M

    2017-11-01

    Coal mining-related activities result in a degraded landscape and sites associated with large amounts of dumped waste material. The arid soil resulting from acid mine drainage affects terrestrial and aquatic ecosystems, and thus, site remediation programs must be implemented to mitigate this sequential deleterious processes. A low-cost alternative material to counterbalance the affected physico-chemical-microbiological aspects of the degraded soil is the amendment with low contaminated and stabilized industrial organic sludge. The content of nutrients P and N, together with stabilized organic matter, makes this material an excellent fertilizer and soil conditioner, fostering biota colonization and succession in the degraded site. However, choice of native plant species to restore a degraded site must be guided by some minimal criteria, such as plant survival/adaptation and plant biomass productivity. Thus, in this 3-month study under environmental conditions, phytoproductivity tests with five native plant species (Surinam cherry Eugenia uniflora L., C. myrianthum-Citharexylum myrianthum, Inga-Inga spp., Brazilian peppertree Schinus terebinthifolius, and Sour cherry Prunus cerasus) were performed to assess these criteria, and additional biochemical parameters were measured in plant tissues (i.e., protein content and peroxidase activity) exposed to different soil/sludge mixture proportions. The results show that three native plants were more adequate to restore vegetation on degraded sites: Surinam cherry, C. myrianthum, and Brazilian peppertree. Thus, this study demonstrates that phytoproductivity tests associated with biochemical endpoint measurements can help in the choice of native plant species, as well as aiding in the choice of the most appropriate soil/stabilized sludge proportion in order to optimize biomass production.

  11. Thermal analysis of kieselguhr sludge

    Directory of Open Access Journals (Sweden)

    S. T. Antipov

    2013-01-01

    Full Text Available It’s currently necessary to clarify the mechanisms of thermodynamic and mass transfer processes in capillary porous media. In this paper we obtain the thermogravimetric curves of evaporation drying kieselguhr sludge. It is also an analysis of the curves, allowing to choose the optimum conditions of drying.

  12. Functional strategies of tropical dry forest plants in relation to growth form and isotopic composition

    Science.gov (United States)

    Santiago, L. S.; Silvera, K.; Andrade, J. L.; Dawson, T. E.

    2017-11-01

    Tropical dry forests (TDFs) undergo a substantial dry season in which plant species must endure several months of drought. Although TDFs support a diverse array of plant growth forms, it is not clear how they vary in mechanisms for coping with seasonal drought. We measured organic tissue stable isotopic composition of carbon (δ13C) and nitrogen (δ15N) across six plant growth forms including epiphytes, terrestrial succulents, trees, shrubs, herbs, and vines, and oxygen (δ18O) of four growth forms, to distinguish among patterns of resource acquisition and evaluate mechanisms for surviving annual drought in a lowland tropical dry forest in Yucatan, Mexico. Terrestrial succulent and epiphyte δ13C was around –14‰, indicating photosynthesis through the Crassulacean acid metabolism pathway, and along with one C4 herb were distinct from mean values of all other growth forms, which were between –26 and –29‰ indicating C3 photosynthesis. Mean tissue δ15N across epiphytes was –4.95‰ and was significantly lower than all other growth forms, which had values around +3‰. Tissue N concentration varied significantly among growth forms with epiphytes and terrestrial succulents having significantly lower values of about 1% compared to trees, shrubs, herbs and vines, which were around 3%. Tissue C concentration was highest in trees, shrubs and vines, intermediate in herbs and epiphytes and lowest in terrestrial succulents. δ18O did not vary among growth forms. Overall, our results suggest several water-saving aspects of resource acquisition, including the absolute occurrence of CAM photosynthesis in terrestrial succulents and epiphytes, high concentrations of leaf N in some species, which may facilitate CO2 drawdown by photosynthetic enzymes for a given stomatal conductance, and potentially diverse N sources ranging from atmospheric N in epiphytes with extremely depleted δ15N values, and a large range of δ15N values among trees, many of which are legumes and

  13. Thin layer convective air drying of wild edible plant (Allium roseum) leaves: experimental kinetics, modeling and quality.

    Science.gov (United States)

    Ben Haj Said, Leila; Najjaa, Hanen; Farhat, Abdelhamid; Neffati, Mohamed; Bellagha, Sihem

    2015-06-01

    The present study deals with the valorization of an edible spontaneous plant of the Tunisian arid areas: Allium roseum. This plant is traditionally used for therapeutic and culinary uses. Thin-layer drying behavior of Allium roseum leaves was investigated at 40, 50 and 60 °C drying air temperatures and 1 and l.5 m/s air velocity, in a convective dryer. The increase in air temperature significantly affected the moisture loss and reduced the drying time while air velocity was an insignificant factor during drying of Allium roseum leaves. Five models selected from the literature were found to satisfactorily describe drying kinetics of Allium roseum leaves for all tested drying conditions. Drying data were analyzed to obtain moisture diffusivity values. During the falling rate-drying period, moisture transfer from Allium roseum leaves was described by applying the Fick's diffusion model. Moisture diffusivity varied from 2.55 × 10(-12) to 8.83 × 10(-12) m(2)/s and increased with air temperature. Activation energy during convective drying was calculated using an exponential expression based on Arrhenius equation and ranged between 46.80 and 52.68 kJ/mol. All sulfur compounds detected in the fresh leaves were detected in the dried leaves. Convective air drying preserved the sulfur compounds potential formation.

  14. [Effects of irrigation and planting pattern on winter wheat water consumption characteristics and dry matter production].

    Science.gov (United States)

    Dong, Hao; Chen, Yu-Hai; Zhou, Xun-Bo

    2013-07-01

    Taking high-yield winter wheat cultivar 'Jimai 22' as test material, a field experiment was conducted in 2008-2010 to study the effects of different irrigation and planting modes on the water consumption characteristics and dry matter accumulation and distribution of winter wheat. Three planting patterns (uniform row, wide-narrow row, and furrow) and four irrigation schedules (no irrigation, W0; irrigation at jointing stage, W1; irrigation at jointing and anthesis stages, W2; and irrigation at jointing, anthesis, and milking stages, W3; with 60 mm per irrigation) were installed. With increasing amount of irrigation, the total water consumption and the ratio of irrigation water to total water consumption under different planting patterns all increased, while the soil water consumption and its ratio to total water consumption decreased significantly. As compared with W0, the other three irrigation schedules had a higher dry matter accumulation after anthesis and a higher grain yield, but a lower water use efficiency (WUE). Under the same irrigation schedules, furrow pattern had higher water consumption ratio, grain yield, and WUE. Taking the grain yield and WUE into consideration, furrow pattern combined with irrigation at jointing and anthesis stages would be the optimal water-saving and planting modes for the winter wheat production in North China Plain.

  15. Distribution of Cenozoic plant relicts in China explained by drought in dry season.

    Science.gov (United States)

    Huang, Yongjiang; Jacques, Frédéric M B; Su, Tao; Ferguson, David K; Tang, Hui; Chen, Wenyun; Zhou, Zhekun

    2015-09-15

    Cenozoic plant relicts are those groups that were once widespread in the Northern Hemisphere but are now restricted to some small isolated areas as a result of drastic climatic changes. They are good proxies to study how plants respond to climatic changes since their modern climatic requirements are known. Herein we look at the modern distribution of 65 palaeoendemic genera in China and compare it with the Chinese climatic pattern, in order to find a link between the plant distribution and climate. Central China and Taiwan Island are shown to be diversity centres of Cenozoic relict genera, consistent with the fact that these two regions have a shorter dry season with comparatively humid autumn and spring in China. Species distribution models indicate that the precipitation parameters are the most important variables to explain the distribution of relict genera. The Cenozoic wide-scale distribution of relict plants in the Northern Hemisphere is therefore considered to be linked to the widespread humid climate at that time, and the subsequent contraction of their distributional ranges was probably caused by the drying trend along with global cooling.

  16. Irradiation of municipal sludge for agricultural use

    Science.gov (United States)

    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.

  17. Select Generic Dry-Storage Pilot Plant Design for Safeguards and Security by Design (SSBD) per Used Fuel Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Demuth, Scott Francis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sprinkle, James K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-26

    As preparation to the year-end deliverable (Provide SSBD Best Practices for Generic Dry-Storage Pilot Scale Plant) for the Work Package (FT-15LA040501–Safeguards and Security by Design for Extended Dry Storage), the initial step was to select a generic dry-storage pilot plant design for SSBD. To be consistent with other DOE-NE Fuel Cycle Research and Development (FCR&D) activities, the Used Fuel Campaign was engaged for the selection of a design for this deliverable. For the work Package FT-15LA040501–“Safeguards and Security by Design for Extended Dry Storage”, SSBD will be initiated for the Generic Dry-Storage Pilot Scale Plant described by the layout of Reference 2. SSBD will consider aspects of the design that are impacted by domestic material control and accounting (MC&A), domestic security, and international safeguards.

  18. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Edward Levy

    2005-10-01

    Low rank fuels such as subbituminous coals and lignites contain significant amounts of moisture compared to higher rank coals. Typically, the moisture content of subbituminous coals ranges from 15 to 30 percent, while that for lignites is between 25 and 40 percent, where both are expressed on a wet coal basis. High fuel moisture has several adverse impacts on the operation of a pulverized coal generating unit. High fuel moisture results in fuel handling problems, and it affects heat rate, mass rate (tonnage) of emissions, and the consumption of water needed for evaporative cooling. This project deals with lignite and subbituminous coal-fired pulverized coal power plants, which are cooled by evaporative cooling towers. In particular, the project involves use of power plant waste heat to partially dry the coal before it is fed to the pulverizers. Done in a proper way, coal drying will reduce cooling tower makeup water requirements and also provide heat rate and emissions benefits. The technology addressed in this project makes use of the hot circulating cooling water leaving the condenser to heat the air used for drying the coal (Figure 1). The temperature of the circulating water leaving the condenser is usually about 49 C (120 F), and this can be used to produce an air stream at approximately 43 C (110 F). Figure 2 shows a variation of this approach, in which coal drying would be accomplished by both warm air, passing through the dryer, and a flow of hot circulating cooling water, passing through a heat exchanger located in the dryer. Higher temperature drying can be accomplished if hot flue gas from the boiler or extracted steam from the turbine cycle is used to supplement the thermal energy obtained from the circulating cooling water. Various options such as these are being examined in this investigation. This is the eleventh Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits

  19. Molecular assessment of ammonia- and nitrite-oxidizing bacteria in full-scale activated sludge wastewater treatment plants.

    Science.gov (United States)

    Robinson, K G; Dionisi, H M; Harms, G; Layton, A C; Gregory, I R; Sayler, G S

    2003-01-01

    Nitrification was assessed in two full-scale wastewater treatment plants (WWTPs) over time using molecular methods. Both WWTPs employed a complete-mix suspended growth, aerobic activated sludge process (with biomass recycle) for combined carbon and nitrogen treatment. However, one facility treated primarily municipal wastewater while the other only industrial wastewater. Real time PCR assays were developed to determine copy numbers for total 16S rDNA (a measure of biomass content), the amoA gene (a measure of ammonia-oxidizers), and the Nitrospira 16S rDNA gene (a measure of nitrite-oxidizers) in mixed liquor samples. In both the municipal and industrial WWTP samples, total 16S rDNA values were approximately 2-9 x 10(13) copies/L and Nitrospira 16S rDNA values were 2-4 x 10(10) copies/L. amoA gene concentrations averaged 1.73 x 10(9) copies/L (municipal) and 1.06 x 10(10) copies/L (industrial), however, assays for two distinct ammonia oxidizing bacteria were required.

  20. Dynamics of microbiological parameters, enzymatic activities and worm biomass production during vermicomposting of effluent treatment plant sludge of bakery industry.

    Science.gov (United States)

    Yadav, Anoop; Suthar, S; Garg, V K

    2015-10-01

    This paper reports the changes in microbial parameters and enzymatic activities during vermicomposting of effluent treatment plant sludge (ETPS) of bakery industry spiked with cow dung (CD) by Eisenia fetida. Six vermibins containing different ratios of ETPS and CD were maintained under controlled laboratory conditions for 15 weeks. Total bacterial and total fungal count increased upto 7th week and declined afterward in all the bins. Maximum bacterial and fungal count was 31.6 CFU × 10(6) g(-1) and 31 CFU × 10(4) g(-1) in 7th week. Maximum dehydrogenase activity was 1921 μg TPF g(-1) h(-1) in 9th week in 100 % CD containing vermibin, whereas maximum urease activity was 1208 μg NH4 (-)N g(-1) h(-1) in 3rd week in 100 % CD containing vermibin. The enzyme activity and microbial counts were lesser in ETPS containing vermibins than control (100 % CD). The growth and fecundity of the worms in different vermibins were also investigated. The results showed that initially biomass and fecundity of the worms increased but decreased at the later stages due to non-availability of the palatable feed. This showed that quality and palatability of food directly affect biological parameters of the system.

  1. Evaluating continuous application of treated sludge on soil and plant productivity

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Busaidi

    2018-01-01

    Full Text Available Kala Compost is a mixture of treated sewage bio-solids and green wastes. It can improve soil fertility and plant growth. However, long-term application of treated sewage bio-solids could result in heavy metals accumulation and some health problems. e objective of this study was to evaluate the e ect of a long run application of Kala compost mixed with chemical fertilizer on soil and plant productivity. Soil and plant (mainly cucumber samples were taken from 12 greenhouses that received Kala compost continuously for the last ve years. No symptoms of physical or chemical problems were observed in the greenhouses and measured soil samples. Moreover, the soil had su cient values of di erent nutrients for plant growth and all measured micronutrients (heavy metals were within the safe limit and below the range of the international standards. An excellent growth was observed in all grown plants and no symptoms of elements de ciency were found. Chemical analysis of fruit samples did not show any accumulation of heavy metals and all measured elements were within the safe limit and did not exceed the international standards. It can be concluded that Kala compost was a good media for plant growth that can enrich the soil with di erent elements needed for higher yield. However, more monitoring is needed with treated bio-solid application but good management could be the key to avoid any adverse e ect of any contaminant.

  2. The beneficial usage of water treatment sludge as pottery product ...

    African Journals Online (AJOL)

    The disposal of sludge from water treatment operations has become a major problem in Malaysia. The problem becomes acute because of scarcity of space for installation of sludge treatment facilities and disposal of treated sludge. Traditionally, treated sludge from water treatment plant will be sent to landfill for disposal.

  3. Current levels and composition profiles of emerging halogenated flame retardants and dehalogenated products in sewage sludge from municipal wastewater treatment plants in China.

    Science.gov (United States)

    Zeng, Lixi; Yang, Ruiqiang; Zhang, Qinghua; Zhang, Haidong; Xiao, Ke; Zhang, Haiyan; Wang, Yawei; Lam, Paul K S; Jiang, Guibin

    2014-11-04

    Occurrence of new toxic chemicals in sludge from wastewater treatment plants (WWTPs) is of concern for the environment and human health. Alternative halogenated flame retardants (HFRs) are a group of potentially harmful organic contaminants in the environment. In this study, a nationwide survey was carried out to identify the occurrence of HFRs and their potential dehalogenated products in sewage sludge from 62 WWTPs in China. Of all 20 target chemicals analyzed, decabromodiphenyl ethane (DBDPE), hexabromocyclododecane (HBCD) and 1, 2-bis (2,4,6-tribromophenoxy)-ethane (BTBPE) were detected in all sludge samples, and the concentrations were in the range of 0.82-215, 0.09-65.8, and 0.10-2.26 ng g(-1) d.w., respectively. Dechlorane Plus (DP) was found in 60 of 62 samples, and the concentration ranged from nd-298 ng g(-1) with a mean of 18.9 ng g(-1) d.w. The anti-DP fractional abundance fanti (0.79) in the samples was much higher than the commercial DP composition (fanti=0.59), indicating a stereoselective degradation. Comparison with global sludge concentrations of HFRs indicate that China is at the medium pollution level in the world. Principal components analysis revealed that strong correlations existed between ln-transformed concentrations (natural logarithm) of the dominant BFRs and total organic carbon (TOC) as well as industrial wastewater proportion, influent volume and serving population. Significant linear relationships (R=0.360-0.893, pproducts, pentabromocyclododecane (PBCD) and undecachloropentacyclooctadecadiene (Cl11-DP), derived from HBCD and DP, were also identified in sewage sludge for the first time.

  4. Gaseous emissions from sewage sludge combustion in a moving bed combustor.

    Science.gov (United States)

    Batistella, Luciane; Silva, Valdemar; Suzin, Renato C; Virmond, Elaine; Althoff, Chrtistine A; Moreira, Regina F P M; José, Humberto J

    2015-12-01

    Substantial increase in sewage sludge generation in recent years requires suitable destination for this residue. This study evaluated the gaseous emissions generated during combustion of an aerobic sewage sludge in a pilot scale moving bed reactor. To utilize the heat generated during combustion, the exhaust gas was applied to the raw sludge drying process. The gaseous emissions were analyzed both after the combustion and drying steps. The results of the sewage sludge characterization showed the energy potential of this residue (LHV equal to 14.5 MJ kg(-1), db) and low concentration of metals, polycyclic aromatic hydrocarbons (PAH), polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF). The concentration of CO, NOx, BTEX (benzene, toluene, ethylbenzene and xylenes) emitted from the sludge combustion process were lower than the legal limits. The overall sludge combustion and drying process showed low emissions of PCDD/PCDF (0.42 ng I-TEQ N m(-3)). BTEX and PAH emissions were not detected. Even with the high nitrogen concentration in the raw feed (5.88% db), the sludge combustion process presented NOx emissions below the legal limit, which results from the combination of appropriate feed rate (A/F ratio), excess air, and mainly the low temperature kept inside the combustion chamber. It was found that the level of CO emissions from the overall sludge process depends on the dryer operating conditions, such as the oxygen content and the drying temperature, which have to be controlled throughout the process in order to achieve low CO levels. The aerobic sewage sludge combustion process generated high SO2 concentration due to the high sulfur content (0.67 wt%, db) and low calcium concentration (22.99 g kg(-1)) found in the sludge. The high concentration of SO2 in the flue gas (4776.77 mg N m(-3)) is the main factor inhibiting PCDD/PCDF formation. Further changes are needed in the pilot plant scheme to reduce SO2 and particulate matter emissions

  5. The length of the dry season may be associated with leaf scleromorphism in cerrado plants.

    Science.gov (United States)

    Souza, Marcelo C; Franco, Augusto C; Haridasan, Mundayatan; Rossatto, Davi R; de Araújo, Janaína F; Morellato, Leonor P C; Habermann, Gustavo

    2015-09-01

    Despite limitations of low fertility and high acidity of the soils, the cerrado flora is the richest amongst savannas. Many cerrado woody species show sclerophyllous leaves, which might be related to the availability of water and nutrients in the soil. To better understand the function and structure of cerrado vegetation within its own variations, we compared two cerrado communities: one in its core region in central Brazil (Brasília, DF) and the other on its southern periphery (Itirapina, SP). We contrasted the length of the dry season, soil fertility rates, leaf concentrations of N, P, K, Ca and Mg and the specific leaf area (SLA) between these communities. The dry season was shorter on the periphery, where the soil was more fertile although more acidic. Plants from the periphery showed higher SLA and higher leaf concentrations of N, P, Ca and Mg. We propose that the higher SLA of plants from the periphery is related to the shorter dry season, which allows better conditions for nutrient uptake.

  6. Disposal Situation of Sewage Sludge from Municipal Wastewater Treatment Plants (WWTPs and Assessment of the Ecological Risk of Heavy Metals for Its Land Use in Shanxi, China

    Directory of Open Access Journals (Sweden)

    Baoling Duan

    2017-07-01

    Full Text Available Land use of sewage sludge is the primary disposal method in Shanxi, accounting for 42.66% of all. To determine the ecological risk of heavy metals in sewage sludge, contents of seven heavy metals in sewage sludge from 9 municipal waste water treatment plants (WWTPs that had the highest application for land use were determined. The order of the measured concentrations was: Zn > Cr > Cu > Ni > Pb > As > Cd, and all heavy metals contents were within the threshold limit values of the Chinese Control Standards for Pollutants in Sludge from Agriculture Use (GB4284-84. Four indices were used to assess the pollution and the ecological risk of heavy metals. By the mean values of the geoaccumulation index (Igeo, heavy metals were ranked in the following order: Cd > Zn > Cu > As > Cr > Ni > Pb. The values showed that the pollution of Zn in station 3 and Cd in station 1, 2, 3, 4, 8 and 9 were heavily; Cu in station 8 and 9, Zn in station 1, 2, 4, 8 and 9 and Cd in station 5 and 7 were moderately to heavily, and the accumulation of other heavy metals were not significant. The single-factor pollution index (PI suggested that none of the stations had heavy metals contamination, except for Cu in station 9, Zn in station 3 and 8, and Cd in station 1 and 9, which were at a moderate level. According to the results of the Nemerow’s synthetic pollution index (PN, sewage sludge from all stations was safe for land use with respect to heavy metals contamination, except for stations 3, 8 and 9, which were at the warning line. The monomial potential ecological risk coefficient (Eri revealed that heavy metals ecological risks in most stations were low. However, station 9 had a moderate risk for Cu; station 6 had a moderate risk, stations 5 and 7 had high risk, other stations had very high risk for Cd. According to the results of the potential ecological risk index (RI, station 1, 8 and 9 had high risk; station 2, 3, 4, 5 and 7 had a moderate risk, and station 6 had a

  7. Disposal Situation of Sewage Sludge from Municipal Wastewater Treatment Plants (WWTPs) and Assessment of the Ecological Risk of Heavy Metals for Its Land Use in Shanxi, China.

    Science.gov (United States)

    Duan, Baoling; Zhang, Wuping; Zheng, Haixia; Wu, Chunyan; Zhang, Qiang; Bu, Yushan

    2017-07-21

    Land use of sewage sludge is the primary disposal method in Shanxi, accounting for 42.66% of all. To determine the ecological risk of heavy metals in sewage sludge, contents of seven heavy metals in sewage sludge from 9 municipal waste water treatment plants (WWTPs) that had the highest application for land use were determined. The order of the measured concentrations was: Zn > Cr > Cu > Ni > Pb > As > Cd, and all heavy metals contents were within the threshold limit values of the Chinese Control Standards for Pollutants in Sludge from Agriculture Use (GB4284-84). Four indices were used to assess the pollution and the ecological risk of heavy metals. By the mean values of the geoaccumulation index (I geo ), heavy metals were ranked in the following order: Cd > Zn > Cu > As > Cr > Ni > Pb. The values showed that the pollution of Zn in station 3 and Cd in station 1, 2, 3, 4, 8 and 9 were heavily; Cu in station 8 and 9, Zn in station 1, 2, 4, 8 and 9 and Cd in station 5 and 7 were moderately to heavily, and the accumulation of other heavy metals were not significant. The single-factor pollution index (PI) suggested that none of the stations had heavy metals contamination, except for Cu in station 9, Zn in station 3 and 8, and Cd in station 1 and 9, which were at a moderate level. According to the results of the Nemerow's synthetic pollution index (PN), sewage sludge from all stations was safe for land use with respect to heavy metals contamination, except for stations 3, 8 and 9, which were at the warning line. The monomial potential ecological risk coefficient (Eri) revealed that heavy metals ecological risks in most stations were low. However, station 9 had a moderate risk for Cu; station 6 had a moderate risk, stations 5 and 7 had high risk, other stations had very high risk for Cd. According to the results of the potential ecological risk index (RI), station 1, 8 and 9 had high risk; station 2, 3, 4, 5 and 7 had a moderate risk, and station 6 had a low risk. The

  8. Occurrence, fate and ecotoxicological assessment of pharmaceutically active compounds in wastewater and sludge from wastewater treatment plants in Chongqing, the Three Gorges Reservoir Area

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Qing, E-mail: qyan2005@hotmail.com [Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environments of Ministry of Education, Chongqing University, Chongqing 400045 (China); College of Geography Science and Tourism, Chongqing Normal University, Chongqing 400047 (China); Gao, Xu, E-mail: gaoxu@cqu.edu.cn [Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environments of Ministry of Education, Chongqing University, Chongqing 400045 (China); Chen, You-Peng [Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environments of Ministry of Education, Chongqing University, Chongqing 400045 (China); Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 401122 (China); Peng, Xu-Ya; Zhang, Yi-Xin; Gan, Xiu-Mei; Zi, Cheng-Fang [Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environments of Ministry of Education, Chongqing University, Chongqing 400045 (China); Guo, Jin-Song [Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environments of Ministry of Education, Chongqing University, Chongqing 400045 (China); Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 401122 (China)

    2014-02-01

    The occurrence, removal and ecotoxicological assessment of 21 pharmaceutically active compounds (PhACs) including antibiotics, analgesics, antiepileptics, antilipidemics and antihypersensitives, were studied at four municipal wastewater treatment plants (WWTP) in Chongqing, the Three Gorges Reservoir Area. Individual treatment unit effluents, as well as primary and secondary sludge, were sampled and analyzed for the selected PhACs to evaluate their biodegradation, persistence and partitioning behaviors. PhACs were identified and quantified using high performance liquid chromatography/tandem mass spectrometry after solid-phase extraction. All the 21 analyzed PhACs were detected in wastewater and the target PhACs except acetaminophen, ibuprofen and gemfibrozil, were also found in sludge. The concentrations of the antibiotics and SVT were comparable to or even higher than those reported in developed countries, while the case of other target PhACs was opposite. The elimination of PhACs except acetaminophen was incomplete and a wide range of elimination efficiencies during the treatment were observed, i.e. from “negative removal” to 99.5%. The removal of PhACs was insignificant in primary and disinfection processes, and was mainly achieved during the biological treatment. Based on the mass balance analysis, biodegradation is believed to be the primary removal mechanism, whereas only about 1.5% of the total mass load of the target PhACs was removed by sorption. Experimentally estimated distribution coefficients (< 500 L/kg, with a few exceptions) also indicate that biodegradation/transformation was responsible for the removal of the target PhACs. Ecotoxicological assessment indicated that the environment concentrations of single compounds (including sulfadiazine, sulfamethoxazole, ofloxacin, azithromycin and erythromycin-H{sub 2}O) in effluent and sludge, as well as the mixture of the 21 detected PhACs in effluent, sludge and receiving water had a significant

  9. EVALUATION OF FGD DRY INJECTION SORBENTS AND ADDITIVES - VOLUME 2 - PILOT PLANT EVALUATION OF HIGH REACTIVITY SORBENTS

    Science.gov (United States)

    The report describes a mini-pilot test program to investigate potential new sorbents and processes for dry SO2 removal. Initial tests showed that the 85 cu m/h pilot plant could be used successfully to evaluate both spray dryer and dry injection processes using traditional calciu...

  10. Gene expression programming approach for the estimation of moisture ratio in herbal plants drying with vacuum heat pump dryer

    Science.gov (United States)

    Dikmen, Erkan; Ayaz, Mahir; Gül, Doğan; Şahin, Arzu Şencan

    2017-07-01

    The determination of drying behavior of herbal plants is a complex process. In this study, gene expression programming (GEP) model was used to determine drying behavior of herbal plants as fresh sweet basil, parsley and dill leaves. Time and drying temperatures are input parameters for the estimation of moisture ratio of herbal plants. The results of the GEP model are compared with experimental drying data. The statistical values as mean absolute percentage error, root-mean-squared error and R-square are used to calculate the difference between values predicted by the GEP model and the values actually observed from the experimental study. It was found that the results of the GEP model and experimental study are in moderately well agreement. The results have shown that the GEP model can be considered as an efficient modelling technique for the prediction of moisture ratio of herbal plants.

  11. Double stage dry-wet-fermentation - start-up of a pilot biogas plant

    International Nuclear Information System (INIS)

    Buschmann, Jeannette; Busch, Gunter; Burkhardt, Marko

    2009-01-01

    The Brandenburg University of Technology (BTU) has developed a double stage dry-wet fermentation process for fast and safe anaerobic degradation. Originally designed for treatment of organic wastes, this process allows using a wide variety of solid biodegradable materials. The dividing of hydrolysis and methanation in this process, allows an optimization of the different steps of biogas generation separately. The main advantages of the process are the optimum process control, an extremely stable process operation and a high gas productivity and quality. Compared to conventional processes, the retention times within the percolation stage (hydrolysis) are reduced considerably. In cooperation with the engineering and consulting company GICON, the technology was qualified further to an industrial scale. In 2007 a pilot plant, and, simultaneously, an industrial plant were built by GICON based on this double stage technology. Based on practical experience from the operation of laboratory fermentation plants, the commissioning of the pilot plant was planned, controlled and monitored by our institution. The start-up of a biogas plant of this type focuses mainly on the inoculation the of methane reactor. The growth of microbial populations and generation of a stable biocenosis within the methane reactor is essential and affects the duration of starting period as well as the methanation efficiency a long time afterwards. This paper concerns with start-up of a pilot biogas plant and discusses particular occurrences and effects during this period. (author)

  12. Adubação do milho: IX - Ensaio com lôdo de fossas sépticas "OMS" Fertilizer experiments with corn: IX - Trial with dried sewage sludge

    Directory of Open Access Journals (Sweden)

    G. P. Viégas

    1956-01-01

    Full Text Available No presente artigo os autores apresentam os resultados de um ensaio conduzido em terra roxa misturada, na Estação Experimental Central, Campinas, para estudar o efeito, na cultura do milho, do adubo OMS completado ou não com fósforo e potássio. O adubo OMS é um pó resultante da decantação, em tanques sépticos, do material de esgotos das cidades, contendo aproximadamente 10% de umidade, 45% de matéria orgânica, 2,5% de N, 0,7% de P2O5 e 0,2% de K2O. O ensaio constou de 16 tratamentos compreendendo tôdas as combinações de: 1 0, 2,5, 5 e 10 t/ha de adubo OMS; 2 0 e 80 kg/ha de P2O5 na forma de farinha de ossos e 3 0 e 50 kg/ha de K.,0 na forma de cinzas de café (que também forneceram 20 kg/ha de P2O5. Os adubos foram empregados somente no primeiro ano, 1943-44, mas o ensaio foi conduzido durante três anos. O efeito do fósforo foi muito pequeno (provavelmente porque a terra havia sido adubada com adubos fosfatados nas culturas anteriores ao ensaio, ao passo que o potássio aumentou extraordinariamente a produção no primeiro ano e teve magnífico efeito residual nos dois anos seguintes. O efeito do adubo OMS foi pequeno na ausência do potássio, mas elevou-se substancialmente na presença dêsse nutriente. As doses de 5 e 10 t/ha deram resultados satisfatórios; contudo, aumentaram relativamente mais a produção de colmos que a de grãos. O efeito do nitrogênio de OMS foi rápido, mas aparentemente pouco duradouro. Para melhor aproveitamento do seu nitrogênio, a aplicação do adubo OMS deveria ser feita com freqüência (talvez anualmente e em doses moderadas, completadas, conforme a terra, com fósforo e potássio.This paper reports the results of an experiment conducted in "terra roxa misturada" soil at the Central Experiment Station, Campinas, to study mainly the effect of dried sewage sludge as a fertilizer for corn. The product contained approximately 10% water, 45% organic matter, 2.5% N, 0.7% P2O5, and 0.2% K2O and

  13. Influence of anaerobic co-digestion of sewage and brewery sludges on biogas production and sludge quality.

    Science.gov (United States)

    Pecharaply, Athapol; Parkpian, Preeda; Annachhatre, Ajit P; Jugsujinda, Aroon

    2007-06-01

    potassium (K) 0.95-0.96%. The heavy metals, chromium (Cr) and copper (Cu) remaining in digested sludge were present at relatively high levels (Cr 1,849-4,230 and Cu 930-2,526 mg/kg dried sludge). The metals were present as organic matter-bound and sulfide-bound fractions that are not soluble and available. The digested sludge could be safely applied to soil as a plant nutrient source, without fecal coliforms or heavy metals risk. A sludge mixture ratio of 25:75 (sewage:brewery), which generated the higher nutrient concentrations (N=4.22%, P=3.20% and K=0.95%), biogas production and treatment efficiency meet the Bangkok Metropolitan Administration (BMA) safety guidelines required for agricultural application. Biogas production and methane at the 25:75 ratio (sewage:brewery) yielded highest amount of VSremoved (0.65 m3/kg) and CODremoved (220 L/kg), respectively.

  14. Energy and water conservation at lignite-fired power plants using drying and water recovery technologies

    International Nuclear Information System (INIS)

    Liu, Ming; Qin, Yuanzhi; Yan, Hui; Han, Xiaoqu; Chong, Daotong

    2015-01-01

    Highlights: • Pre-drying and water recovery technologies were used to conserve energy and water. • The energy and water conservation potential were analyzed with reference cases. • The air-cooling unit produces water when the water content of lignite is high enough. • Influences of main parameters on energy and water conservation were analyzed. - Abstract: Lignite is considered as a competitive energy raw material with high security of supply viewed from a global angle. However, lignite-fired power plants have many shortcomings, including high investment, low energy efficiency and high water use. To address these issues, the drying and water recovery technologies are integrated within lignite-fired power plants. Both air-cooling and wet-cooling units with three kinds of lignite as feeding fuel were analyzed quantitatively. Results showed that energy conservation and water conservation are obtained simultaneously. The power plant firing high moisture lignite becomes more environmental friendly with higher power generation efficiency and a lower water makeup rate than the one firing low moisture lignite. And further calculation revealed that the air-cooling unit needs no makeup water and even produces some water as it generates power, when the water carrying coefficient is higher than 40 g/MJ.

  15. Production of oil and coke from sludges containing organic pollutants; Gewinnung von Oel und Koks aus organisch belasteten Schlaemmen

    Energy Technology Data Exchange (ETDEWEB)

    Steger, M. [Martin Steger GmbH, Eggenfelden (Germany); Meissner, W.; Herold, R. [Max Aicher Umwelttechnik GmbH, Freilassing (Germany)

    1998-09-01

    Since the mid-eighties, Messrs. Max Aicher Umwelttechnik GmbH at Hammerau, Germany have been investigating sewage sludge pyrolysis. Laboratory experiments and semi-industrial investigations led to the construction of a combined sludge drying and conversion plant (``Aicher sludge recycling process``), in which the organic sludge fraction is converted into recyclable or combustible oils. Carbon is obtained as a by-product in solid form as conversion coke which can be utilized. Apart from sewage sludge, also industrial sludges with high organic fractions can be processed, e.g. sludges and sewage sludges from petroleum processing. (orig.) [Deutsch] In der Bundesrepublik Deutschland beschaeftigt sich die Max Aicher Umwelttechnik GmbH in Hammerau seit Mitte der Achtzigerjahre mit der Niedertemperaturkonvertierung (Pyrolyse) von Klaerschlamm. Versuche im Labor- und im halbtechnischen Massstab fuehrten zur Realisierung einer betriebstechnischen Anlage mit den Komponenten Schlammtrocknung und Konvertierung. Ziel des Aicher-Schlamm-Recycling-Verfahrens ist die Umwandlung der organischen Schlammfraktion in stofflich und energetisch verwertbare Oele. Bei der Umwandlung entsteht fixer Kohlenstoff, der im festen Rueckstand (Konversionskoks) angereichert wird. Neben dem gewonnenen Oel ist auch der produzierte Koks verwertbar. Einsatzstoffe fuer das Verfahren sind neben Klaerschlamm aus der kommunalen Abwasserreinigung vor allem industrielle Schlaemme mit hohen organischen Anteilen z.B. Schlaemme und Klaerschlaemme aus der Erdoelverarbeitung. (orig.)

  16. Anaerobic bioleaching of metals from waste activated sludge

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-01

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

  17. Fractionation and business potential from sludge (Pafrak)