WorldWideScience

Sample records for dewatered sewage sludge

  1. Dewatering properties of differently treated sewage sludge

    International Nuclear Information System (INIS)

    Zehnder, H.J.

    1977-01-01

    A study on dewatering properties of radiosterilized sewage sludge of different type and origin was carried out. For comparison, also heat-treated (pasteurized) sludge was investigated. The specific filtration resistance of irradiated sewage sludge was lowered in all types of sludge examined. In general, pasteurization increased this parameter. The settling properties of irradiated digested sewage sludge was slightly improved, mainly in the first hours after treatment. Microbial effects may mask the real sedimentation relations especcially in aerobically stabilized sludges. A pasteurization treatment of sewage sludge caused an increased content of soluble substances and suspended particles in the supernatant water. The supernatant water from irradiated sludge showed a smaller increase

  2. 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.

  3. Highly efficient secondary dewatering of dewatered sewage sludge using low boiling point solvents.

    Science.gov (United States)

    He, Chao; Chena, Chia-Lung; Xu, Zhirong; Wang, Jing-Yuan

    2014-01-01

    Secondary dewatering of dewatered sludge is imperative to make conventional drying and incineration of sludge more economically feasible. In this study, a secondary dewatering of dewatered sludge with selected solvents (i.e. acetone and ethanol) followed by vacuum filtration and nature drying was investigated to achieve in-depth dewatering. After the entire secondary dewatering process, the sludge was shown to be odourless and the organic matter content was greatly retained. Increased mean particle size of sludge after solvent contact improved solid-liquid separation. With an acetone/sludge ratio of 3:1 (mL:g) in solvent contact and subsequent nature drying at ambient temperature after 24 h, the moisture content of sludge can be reduced to a level less than 20%. It is found that the polysaccharides were mainly precipitated by acetone, whereas the release ratios of protein and DNA were increased significantly as the added acetone volumes were elevated. During nature drying, accumulated evaporation rates of the sludge after solvent contact were 5-6 times higher than original dewatered sludge. Furthermore, sludge after acetone contact had better nature drying performance than ethanol. The two-stage dewatering involves solvent contact dewatering and solvent enhanced evaporation dewatering. Through selecting an appropriate solvent/sludge ratio as well as economical solvents and minimizing the solvent loss in a closed-pilot system, this dewatering process can be competitive in industrial applications. Therefore, this solvent-aided secondary dewatering is an energy-saving technology for effective in-depth dewatering of dewatered sludge and subsequent sludge utilization.

  4. Use of a water treatment sludge in a sewage sludge dewatering process

    Science.gov (United States)

    Górka, Justyna; Cimochowicz-Rybicka, Małgorzata; Kryłów, Małgorzata

    2018-02-01

    The objective of the research study was to determine whether a sewage sludge conditioning had any impact on sludge dewaterability. As a conditioning agent a water treatment sludge was used, which was mixed with a sewage sludge before a digestion process. The capillary suction time (CST) and the specific filtration resistance (SRF) were the measures used to determine the effects of a water sludge addition on a dewatering process. Based on the CST curves the water sludge dose of 0.3 g total volatile solids (TVS) per 1.0 g TVS of a sewage sludge was selected. Once the water treatment sludge dose was accepted, disintegration of the water treatment sludge was performed and its dewaterability was determined. The studies have shown that sludge dewaterability was much better after its conditioning with a water sludge as well as after disintegration and conditioning, if comparing to sludge with no conditioning. Nevertheless, these findings are of preliminary nature and future studies will be needed to investigate this topic.

  5. Thermal conductivity characteristics of dewatered sewage sludge by thermal hydrolysis reaction.

    Science.gov (United States)

    Song, Hyoung Woon; Park, Keum Joo; Han, Seong Kuk; Jung, Hee Suk

    2014-12-01

    The purpose of this study is to quantify the thermal conductivity of sewage sludge related to reaction temperature for the optimal design of a thermal hydrolysis reactor. We continuously quantified the thermal conductivity of dewatered sludge related to the reaction temperature. As the reaction temperature increased, the dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. Therefore, the bound water in the sludge cells comes out as free water, which changes the dewatered sludge from a solid phase to slurry in a liquid phase. As a result, the thermal conductivity of the sludge was more than 2.64 times lower than that of the water at 20. However, above 200, it became 0.704 W/m* degrees C, which is about 4% higher than that of water. As a result, the change in physical properties due to thermal hydrolysis appears to be an important factor for heat transfer efficiency. Implications: The thermal conductivity of dewatered sludge is an important factor the optimal design of a thermal hydrolysis reactor. The dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. The liquid phase slurry has a higher thermal conductivity than pure water.

  6. STABILIZATION OF DEWATERED SEWAGE SLUDGE BY AEROBIC COMPOSTING METHOD: USING SAWDUST AS BULKING AGENTS

    Directory of Open Access Journals (Sweden)

    A PARVARESH

    2002-12-01

    Full Text Available Introduction. Sludge production from municipal wastewater treatment plants should have quality standards before disposal in to the environment. Environmental specialists classified sewage sludge as a hazardous waste because of high organic compounds and pathogenic microorganisms. They belive that sewage should be stabilized before disposal and so composting of sewage sludge is an effective and economical method to stabilize. Sewage sludge compost could be used to improve soil structure and enrich the soil with nutrients. Methods. To evaluate the optimum conditions of aerobic compost, the mixture of dewatered sewage sludge from Isfahan municipal waste water treatment plant and sawdust as bulking agent were used. Pilot scale study were performed in Isfahan municipal waste water treatment plant. To perform this research project, the dewatered sewage sludge with humidity between 78 to 82 percent were mixed with sawdust. Turning over method of the piles with one week interval were applied to aerate the mixture. Temperature of the piles were monitored at different depths daily. Other parameters such as N, G, organic matters and pH were determined weekly. Total and fecal coli form, and salmonella were determined at the beginning and end of the composting process, also heavy metals were measured at the same time. Results. The results of this study showed that after days, temperature of the mixture reached up to 55 G, and were stabled for 15 days. Humidity, organic matter, organic carbon and GIN ratio of the mixture decreased over the period of the study, due to increasing the temperature. Also organic matter and humidity mainly decreased in thermofilic phase. The number of total and fecal coliform and also salmonella decreased to A class standards of US.EPA at the end of the operation. Discussion. The results of the study also showed that, this type of composting method is reliable, and simple to schedule, with high flexibility and low odor

  7. Effect of biodegradation on the consolidation properties of a dewatered municipal sewage sludge.

    Science.gov (United States)

    O'Kelly, Brendan C

    2008-01-01

    The effect of biodegradation on the consolidation characteristics of an anaerobically digested, dewatered municipal sewage sludge was studied. Maintained-load oedometer consolidation tests that included measurement of the pore fluid pressure response were conducted on moderately degraded sludge material and saturated bulk samples that had been stored under static conditions and allowed to anaerobically biodegrade further (simulating what would happen in an actual sewage sludge monofill or lagoon condition). Strongly degraded sludge material was produced after a storage period of 13 years at ambient temperatures of 5-15 degrees C, with the total volatile solids reducing from initially 70% to 55%. The sludge materials were highly compressible, although impermeable for practical purposes. Primary consolidation generally occurred very slowly, which was attributed to the microstructure of the solid phase, the composition and viscosity of the pore fluid, ongoing biodegradation and the high organic contents. The coefficient of primary consolidation values decreased from initially about 0.35m2/yr to 0.003-0.03m2/yr with increasing effective stress (sigmav'=3-100kPa). Initially, the strongly degraded sludge material was slightly more permeable, although both the moderately and strongly degraded materials became impermeable for practical purposes (k=10(-9)-10(-12)m/s) below about 650% and 450% water contents, respectively. Secondary compression became more dominant with increasing effective stress with a mean secondary compression index (Calphae) value of 0.9 measured for both the moderately and strongly degraded materials.

  8. A review on sludge dewatering indices.

    Science.gov (United States)

    To, Vu Hien Phuong; Nguyen, Tien Vinh; Vigneswaran, Saravanamuth; Ngo, Huu Hao

    2016-01-01

    Dewatering of sludge from sewage treatment plants is proving to be a significant challenge due to the large amounts of residual sludges generated annually. In recent years, research and development have focused on improving the dewatering process in order to reduce subsequent costs of sludge management and transport. To achieve this goal, it is necessary to establish reliable indices that reflect the efficiency of sludge dewatering. However, the evaluation of sludge dewaterability is not an easy task due to the highly complex nature of sewage sludge and variations in solid-liquid separation methods. Most traditional dewatering indices fail to predict the maximum cake solids content achievable during full-scale dewatering. This paper reviews the difficulties in assessing sludge dewatering performance, and the main techniques used to evaluate dewatering performance are compared and discussed in detail. Finally, the paper suggests a new dewatering index, namely the modified centrifugal index, which is demonstrated to be an appropriate indicator for estimating the final cake solids content as well as simulating the prototype dewatering process.

  9. [Magnetic Fe₃O₄Microparticles Conditioning-Pressure Electro-osmotic Dewatering (MPEOD) of Sewage Sludge].

    Science.gov (United States)

    Qian, Xu; Wang, Yi-li; Zhao, Li

    2016-05-15

    For magnetic Fe₃O₄ microparticles conditioning--pressure electro-osmotic dewatering (MPEOD) process of activated sludge (AS), the effects of operating parameters (optimal dosage of Fe₃O₄, electric field duration, mechanical pressure and voltage) on the dewatering efficiency and energy consumption were investigated, and the optimal conditions were determined. Moreover, the properties of supernatant and sludge along MPEOD process were studied as well as the interaction force between the sludge biosolids. Taking the energy consumption into consideration, the results showed that the optimal dewatering effect for AS could be achieved with a magnetic Fe₃O₄ microparticles dosage of 0.15 g · g⁻¹, an electric field duration of 2 h, a mechanical pressure of 400-600 kPa and a voltage of 30-50 V. When MPEOD was conducted at 400 kPa and 50 V for 2 h, the sludge reduction rate reached 98.30%, the percentage of water removal was 99.34% and the moisture content of AS decreased from 99.18% to 44.46%. The corresponding consumption of energy was 0.013 3 kW · h · kg⁻¹. The coagulation mechanism played a slight role in the AS conditioning with magnetic Fe₃O₄ micro-particles. In fact, magnetic Fe₃O₄micro-particles could greatly decrease the acid-base interaction (WA) between AS biosolids, cause floc growth and enlarge pores in AS aggregates, which will be beneficial to AS dewatering. Compared to DLVO theory, the extended DLVO theory could accurately describe the aggregation and dispersion behavior of sludge particles.

  10. Hydrothermal and alkaline hydrothermal pretreatments plus anaerobic digestion of sewage sludge for dewatering and biogas production: Bench-scale research and pilot-scale verification.

    Science.gov (United States)

    Li, Chunxing; Wang, Xingdong; Zhang, Guangyi; Yu, Guangwei; Lin, Jingjiang; Wang, Yin

    2017-06-15

    To test the feasibility and practicability of the process combing hydrothermal pretreatment for dewatering with biogas production for full utilization of sewage sludge, hydrothermal/alkaline hydrothermal pretreatments and in turn anaerobic digestion of the filtrates obtained after dewatering the pretreated sludge were performed at bench- and pilot-scales. The hydrothermal temperature fell within the range of 140 °C-220 °C and the pretreatment time varied from 30 min to 120 min. For the alkaline hydrothermal pretreatment the pH value of the sludge was adjusted to 9.0-11.0 by adding Ca(OH) 2 . The results showed that the dewaterability of the sewage sludge was improved with increasing pretreatment temperature but the impact of the pretreatment time was not significant. The addition of Ca(OH) 2 gave better performance on the subsequent mechanical dewatering of the pretreated sludge compared to pure hydrothermal pretreatment, and the higher the pH value was, the better the dewaterability of the pretreated sludge was. The conditions of 180 °C/30 min and 160 °C/60 min/pH = 10.0 (for hydrothermal and alkaline hydrothermal pretreatments, respectively) resulted in relatively good results in the theoretical energy balance, which were verified in the pilot-scale tests. Based on the data from the pilot tests, the alkaline hydrothermal process realized self-sufficiency in energy at the cost of a proper amount of CaO. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Reuse of liquid, dewatered, and composted sewage sludge on agricultural land: effects of long-term application on soil and crop.

    Science.gov (United States)

    Mantovi, Paolo; Baldoni, Guido; Toderi, Giovanni

    2005-01-01

    To evaluate the effects of repeated sewage sludge applications in comparison to mineral fertilisers on a winter wheat-maize-sugar beet rotation, a field experiment on a silty-loam soil, in the eastern Po Valley (Italy), was carried out since 1988. Municipal-industrial wastewater sludge as anaerobically digested, belt filtered (dewatered), and composted with wheat straw, has been applied at 5 and 10 Mg DM ha(-1)yr(-1). Biosolids gave crop yields similar to the highest mineral fertiliser dressing. However, with the higher rate of liquid and dewatered sludge, excessive N supply was harmful, leading to wheat lodging and poor quality of sugar beet and wheat crops. From this standpoint compost use was safer. Biosolids increased organic matter (OM), total N, and available P in the soil and reduced soil alkalinity, with more evident effects at the highest rate. Compost caused the most pronounced OM top soil accumulation. Significant accumulations of total Zn and Cu were detected in amended top soil, but no other heavy metals (Cd, Cr, Ni, Pb), whose total concentration remained well below the hazard limits. Biosolid applications significantly increased the content of N, P, Zn, and Cu in wheat grain, N and Cu in sugar beet roots, and only Cu in maize grain. The application of biosolids brought about notable benefits to soil fertility but it was associated with possible negative effects on water quality due to increased P availability and on soil ecology due to Zn accumulation.

  12. Dewatering of sludges

    International Nuclear Information System (INIS)

    Bode, P.

    1984-01-01

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

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

    International Nuclear Information System (INIS)

    Silvestre, G.; Illa, J.; Fernández, B.; Bonmatí, A.

    2014-01-01

    Highlights: • Thermophilic anaerobic codigestion of sewage sludge and grease waste (GW) doubles methane yield. • High GW doses in the influent leads to instability and LCFA accumulation in the effluent. • GW addition promotes acetoclastic activity whilst worsening the hydrogenothrophic activity. • The mesophilic codigestion with GW performs better than the thermophilic one. - Abstract: Thermophilic co-digestion of sewage sludge with three different doses of trapped grease waste (GW) from the pre-treatment of a WWTP has been assessed in a CSTR bench-scale reactor. After adding 12% and 27% of grease waste (on COD basis), the organic loading rate increased from 2.2 to 2.3 and 2.8 kg COD m −3 d −1 respectively, and the methane yield increased 1.2 and 2.2 times. Further GW increase (37% on COD basis) resulted in an unstable methane yield and in long chain fatty acids (LCFA) accumulation. Although this inestability, the presence of volatile fatty acids in the effluent was negligible, showing good adaptation to fats of the thermophilic biomass. Nevertheless, the presence of LCFA in the effluent worsens its dewatering properties. Specific methanogenic activity tests showed that the addition of grease waste ameliorates the acetoclastic activity in detriment of the hydrogenotrophic activity, and suggests that the tolerance to LCFA can be further enhanced by slowly increasing the addition of lipid-rich materials

  14. Dewatering and drying - prerequisites for a safe sewage sludge disposal; Entwaesserung und Trocknung - Voraussetzung fuer eine sichere Klaerschlammentsorgung

    Energy Technology Data Exchange (ETDEWEB)

    Wiesmann, J. [Stadtentwaesserung Zuerich (Switzerland)

    1997-12-31

    Today, besides the agricultural utilization of liquid and drained sludge and the composting, there are the following different disposal ways which come into consideration: - sludge combustion in an independent plant or with garbage together; - utilization as a combustible both in cement and asphalt industry as well as in thermal power stations; - additives in commercial fertilizer or direct utilization as a dry fertilizer in agriculture (phosphorus fertilizer). All these ways demand a sludge product, with a dry content of 55 up to approximately 90 percent. During specification of an as flexible as possible plant in the waste water treatment plant Zurich-Werdhoelzli therefore, was demanded a double stage drying, for the production of both products, one with about 55 percent of dry matter (for combustion without supplementary combustibles) and one of these with 85-95 percent of dry matter. An indirect thin film contact extrusion gear was chosen in order to hold the odour and dust problems as small as possible, a high drying degree, in order to allow the desired corrected piling up and a better handling. This in turn should bring a further flexibility for trading of the sewage sludge product what has again favorable influence on the costs. (orig./SR) [Deutsch] Zur Zeit kommen neben der landwirtschaftlichen Verwertung von fluessigem und entwaessertem Schlamm sowie dem Kompostieren folgende Entsorgungswege in Frage: - Schlammverbrennung in einer eigenstaendigen Anlage oder zusammen mit Muell; - Einsatz als Brennstoff sowohl in der Zement- und Asphaltindustrie wie auch in thermischen Kraftwerken; - Zuschlagstoff in Handelsduenger oder direkter Einsatz als Trockenduenger (Phosphorduenger) in der Landwirtschaft. Alle diese Wege verlangen ein Schlammprodukt, das einen Trockengehalt von 55 resp. rund 90 Prozent aufweisen muss. Bei der Spezifikation einer moeglichst flexiblen Anlage in der Klaeranlage Zuerich-Werdhoelzli wurde deshalb eine zweistufige Trocknung verlangt, die

  15. 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

  16. Assessment of technical-scale dewatering results in decanters on the basis of measurements of water types in sewage sludge; Bestimmung grosstechnischer Entwaesserungsergebnisse in Dekantern basierend auf der Messung der Wasserarten von Klaerschlaemmen

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, J.; Dichtl, N. [Technische Univ. Braunschweig (Germany). Inst. fuer Siedlungswasserwirtschaft

    1999-07-01

    In a sewage sludge suspension, three water portions can be measured and distinguished from each other. The free water portion is not bound to sludge particles and can be separated by mechanical dewatering. The interstitial water portion bound by capillary forces and bound water (on surfaces and in cells) remain in the sludge cake after dewatering. The described measuring system for thermo-gravimetric determination of the water portions of sewage sludge was adjusted and calibrated at Braunschweig Technical University and permits prognosticating the maximum attainable content of solids through mechanical dewatering in high-performance decanters. (orig.) [German] In einer Klaerschlammsuspension koennen drei Wasseranteile messtechnisch unterschieden werden. Der freie Wasseranteil ist nicht an die Schlammpartikel gebunden und ist bei einer maschinellen Entwaesserung abtrennbar. Der kapillar gehaltene Zwischenraumwasseranteil und das gebundene Wasser (auf Oberflaechen und in Zellen) verbleibt nach der Entwaesserung im Schlammkuchen. Die an der TU Braunschweig angepasste und kalibrierte Messanlage zur thermo-gravimetrischen Bestimmung der Wasseranteile eines Klaerschlammes ermoeglicht es, den maximal bei der maschinellen Entwaesserung in Hochleistungsdekantern erreichbaren Feststoffgehalt zu prognostizieren. (orig.)

  17. Insight into effects of electro-dewatering pretreatment on nitrous oxide emission involved in related functional genes in sewage sludge composting.

    Science.gov (United States)

    Wang, Ke; Wu, Yiqi; Wang, Zhe; Wang, Wei; Ren, Nanqi

    2018-05-26

    Electro-dewatering (ED) pretreatment could improve sludge dewatering performance and remove heavy metal, but the effect of ED pretreatment on nitrous oxide (N 2 O) emission and related functional genes in sludge composting process is still unknown, which was firstly investigated in this study. The results revealed that ED pretreatment changed the physicochemical characteristics of sludge and impacted N 2 O related functional genes, resulting in the reduction of cumulative N 2 O emission by 77.04% during 60 days composting. The higher pH and NH 4 + -N, but lower moisture, ORP and NO 2 - -N emerged in the composting of ED sludge compared to mechanical dewatering (MD) sludge. Furthermore, ED pretreatment reduced amoA, hao, narG, nirK and nosZ in ED sludge on Day-10 and Day-60 of composting. It was found that nirK reduction was the major factor impacting N 2 O generation in the initial composting of ED sludge, and the decline of amoA restricted N 2 O production in the curing period. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Operator assisted optimization of sludge dewatering

    DEFF Research Database (Denmark)

    Grüttner, Henrik

    1991-01-01

    by the operator. By graphical presentation and an advisory service these data are used to support the operator in his dewatering operations and to secure a running optimization of the sludge dewatering. Evaluations show that this system is a useful tool for data collection and presentation and that the data...

  19. Osmotic Effects in Sludge Dewatering

    DEFF Research Database (Denmark)

    Keiding, Kristian; Rasmussen, Michael R.

    2003-01-01

    A model of filtration dewatering is presented. The model is based on the d’Arcy flow equation in which the resistance to filtration is described by the Corzeny–Carman equation and the driving force is the difference between the external pressure and the osmotic pressure of the filter cake. It has...

  20. Sewage sludge additive

    Science.gov (United States)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  1. A process combining hydrothermal pretreatment, anaerobic digestion and pyrolysis for sewage sludge dewatering and co-production of biogas and biochar: Pilot-scale verification.

    Science.gov (United States)

    Li, Chunxing; Wang, Xingdong; Zhang, Guangyi; Li, Jie; Li, Zhiwei; Yu, Guangwei; Wang, Yin

    2018-04-01

    To fully dispose of/utilize sewage sludge, a process combing hydrothermal pretreatment (HTPT), anaerobic digestion (AD) and pyrolysis was developed and tested at the pilot scale. First, the improvement in sludge dewaterability by HTPT at 180 °C for 30 min was verified, and the water content decreased from 85 to 33 wt% after filter pressing. Then, the resulting filtrate underwent continuous mesophilic (37 ± 2 °C) AD in an up-flow anaerobic sludge bed (UASB) reactor for producing biogas to compensate for the energy required for HTPT. Meanwhile, the filter cake was pyrolyzed in a rotary furnace (600 ± 50 °C) to generate biochar, and heavy metals were well immobilized in the biochar. Finally, the material/energy balance made according to the pilot data showed that the proposed process was effective for full resource reuse of sewage sludge. Copyright © 2018. Published by Elsevier Ltd.

  2. Performance of Sandy Dry Beds for sludge dewatering

    International Nuclear Information System (INIS)

    Al-Muzaini, S.

    2003-01-01

    Sludge produced by the Jahra treatment plant was assessed. The assessment was directed at determining the performance of sand drying beds. The assessment of quality of the sludge produced was based on the standards for land application of sewage sludge. Analyses were carried out for trace heavy metals and bacteria. The results of analyses showed that the sludge produced was high in organic matter and sand content but low in heavy metals. The collected data indicated that the sand drying beds at the Jahra treatment plant are at present inadequate to handle the projected sludge production. The investigation showed that the sand drying beds are fully used and the plant will require 3-4 times the capacity of the existing drying beds when the plant becomes fully operational. In addition, these sand drying beds are subjected to uncontrollable conditions such as temperature, rainfall and sludge drainage rate. Thus, sand drying beds have become less popular as a dewatering system. This paper evaluates the performance of the existing sand drying beds and suggests the most appropriate technology to alleviate the above mentioned problems. (author)

  3. Electrical field: a historical review of its application and contributions in wastewater sludge dewatering.

    Science.gov (United States)

    Mahmoud, Akrama; Olivier, Jérémy; Vaxelaire, Jean; Hoadley, Andrew F A

    2010-04-01

    Electric field-assisted dewatering, also called electro-dewatering, is a technology in which a conventional dewatering mechanism such a pressure dewatering is combined with electrokinetic effects to realize an improved liquid/solids separation, to increase the final dry solids content and to accelerate the dewatering process with low energy consumption compared to thermal drying. Electro-dewatering is not a new idea, but the practical industrial applications have been limited to niche areas in soil mechanics, civil engineering, and the ceramics industry. Recently, it has received great attention, specially, in the fields of fine-particle sludge, gelatinous sludge, sewage sludge, pharmaceutical industries, food waste and bull kelp, which could not be successfully dewatered with conventional mechanical methods. This review focuses on the scientific and practical aspects of the application of an electrical field in laboratory/industrial dewatering, and discusses this in relation to conventional dewatering techniques. A comprehensive bibliography of research in the electro-dewatering of wastewater sludges is included. As the fine-particle suspensions possess a surface charge, usually negative, they are surrounded by a layer with a higher density of positive charges, the electric double layer. When an electric field is applied, the usually negative charged particles move towards the electrode of the opposite charge. The water, commonly with cations, is driven towards the negative electrode. Electro-dewatering thus involves the well-known phenomena of electrophoresis, electro-osmosis, and electromigration. Following a detailed outline of the role of the electric double layer and electrokinetic phenomena, an analysis of the components of applied voltage and their significance is presented from an electrochemical viewpoint. The aim of this elementary analysis is to provide a fundamental understanding of the different process variables and configurations in order to

  4. Sewage sludges disinfection

    International Nuclear Information System (INIS)

    Alexandre, D.; Gevaudan, P.P.

    1977-01-01

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

  5. 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.

  6. Sewage sludge irradiation with electrons

    International Nuclear Information System (INIS)

    Tauber, M.

    1976-01-01

    The disinfection of sewage sludge by irradiation has been discussed very intensively in the last few months. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. AEG-Telefunken is building an irradiation plant with a 1.5 MeV, 25 mA electron accelerator, to study the main features of electron irradiation of sewage sludge. (author)

  7. Heating value characteristics of sewage sludge: a comparative study of different sludge types

    International Nuclear Information System (INIS)

    Kim, Young-JU.; Kang, Hae-Ok.; Qureshi, T.I.

    2005-01-01

    Heating value characteristics of three different types of sludge, i.e. domestic sewage sludge, industrial sludge, and industrial + domestic sewage sludge were investigated. Industrial + domestic sewage sludge (thickened) showed the highest heating value (5040 kcal/kg) than other sludge types. This may be due to increased amount of organic matter presents in thickened sludge than de-watered sludge. A gradual increase in organic matter of the sludge was observed with the increase of the moisture contents. Heating value of the sludge having 60% moisture contents was found in the range between 924-1656 kcal/kg and this amount was higher than the minimum heating value (800 kcal/kg) required sustaining auto thermal combustion in sludge incineration process. Energy consumption requirement for pre drying sludge operations revealed that industrial sludge (de-watered) required the minimum cost (13 $/ton of sludge) to make it a sludge of fuel grade (60% W), while mixed sludge cost the highest amount for its pre-drying operations. (author)

  8. Sewage sludges disinfection

    International Nuclear Information System (INIS)

    Alexandre, D.

    1977-01-01

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

  9. Rheological properties of disintegrated sewage sludge

    Science.gov (United States)

    Wolski, Paweł

    2017-11-01

    The rheology of the sludge provides information about the capacity and the flow, which in the case of project tasks for the hydraulic conveying installation is an important control parameter. Accurate knowledge of the rheological properties of sludge requires the designation of rheological models. Models single and multiparameter (Ostwald, Bingham, Herschel-Bulkley'a, and others) allow an approximation of flow curves, and the determination of the boundaries of the flow of modified sludge allows you to control the process compaction or are dewatered sludge undergoing flow. The aim of the study was to determine the rheological parameters and rheological models of sludge conditioned by physical methods before and after the process of anaerobic digestion. So far, studies have shown that the application of conditioning in the preparation of sewage sludge increases shear stress, viscosity as well as the limits of flow in relation to the untreated sludge. Offset yield point by the application of a conditioning agent is associated with decreased flowability tested sludge, which has also been observed by analyzing the structure of the prepared samples. Lowering the yield point, and thus the shear stress was recorded as a result of the fermentation test of disintegrated sludge.

  10. 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)

  11. Composting sewage sludge

    International Nuclear Information System (INIS)

    Epstein, E.

    1979-01-01

    Sewage sludge is predominantly organic matter containing domestic and industrial wastes. The inefficiency of the waste water treatment to destroy pathogens and stabilization of odor-producing volatile organic compounds necessitates further treatment before sludge can be used as a soil amendment or fertilizer. Composting, which is the rapid biological decomposition of the sludge organic matter is an excellent method of sludge stabilization. During the process, volatile organics are decomposed and many of the pathogens destoyed. The low cost of the process and its flexibility with respect to labor and capital makes the system highly attractive to municipalities. A major problem facing large urban waste water treatment facilities is the distribution or marketing. The light weight of the material, expensive hauling costs, and low fertilizer value reduce its attractiveness to the agricultural sector. Thus, the greatest market is for horticultural purposes, sod, nurseries, greenhouses, parks, and reclamation areas. The major potential benefits of irradiating compost as a means of further disinfection are: (1) elimination of any health hazard; (2) increase of market potential, i.e., providing more market outlets to distribute the material; (3) compliance with state and federal health regulations; and (4) enhancement of the economics of composting as a result of utilizing compost in speciality products commanding a higher value

  12. 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-plant...

  13. Evaluation of energy consumption during aerobic sewage sludge treatment in dairy wastewater treatment plant.

    Science.gov (United States)

    Dąbrowski, Wojciech; Żyłka, Radosław; Malinowski, Paweł

    2017-02-01

    The subject of the research conducted in an operating dairy wastewater treatment plant (WWTP) was to examine electric energy consumption during sewage sludge treatment. The excess sewage sludge was aerobically stabilized and dewatered with a screw press. Organic matter varied from 48% to 56% in sludge after stabilization and dewatering. It proves that sludge was properly stabilized and it was possible to apply it as a fertilizer. Measurement factors for electric energy consumption for mechanically dewatered sewage sludge were determined, which ranged between 0.94 and 1.5 kWhm -3 with the average value at 1.17 kWhm -3 . The shares of devices used for sludge dewatering and aerobic stabilization in the total energy consumption of the plant were also established, which were 3% and 25% respectively. A model of energy consumption during sewage sludge treatment was estimated according to experimental data. Two models were applied: linear regression for dewatering process and segmented linear regression for aerobic stabilization. The segmented linear regression model was also applied to total energy consumption during sewage sludge treatment in the examined dairy WWTP. The research constitutes an introduction for further studies on defining a mathematical model used to optimize electric energy consumption by dairy WWTPs. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Co-conditioning and dewatering of chemical sludge and waste activated sludge.

    Science.gov (United States)

    Chang, G R; Liu, J C; Lee, D J

    2001-03-01

    The conditioning and dewatering behaviors of chemical and waste activated sludges from a tannery were studied. Capillary suction time (CST), specific resistance to filtration (SRF), and bound water content were used to evaluate the sludge dewatering behaviors. Zeta potentials were also measured. Experiments were conducted on each sludge conditioned and dewatered separately, and on the sludge mixed at various ratios. Results indicate that the chemical sludge was relatively difficult to be dewatered, even in the presence of polyelectrolyte. When the waste activated sludge was mixed with the chemical sludge at ratios of 1:1 and 2:1, respectively, the dewaterability of chemical sludge improved remarkably while the relatively better dewaterability of the waste activated sludge deteriorated only to a limited extent. As the mixing ratios became 4:1 and 8:1, the dewaterability of the mixed sludge was equal to that of the waste activated sludge. The optimal polyelectrolyte dosage for the mixed sludge was equal to or less than that of the waste activated sludge. It is proposed that the chemical sludges act as skeleton builders that reduce the compressibility of the mixed sludge whose dewaterability is enhanced. Bound water contents of sludge decreased at low polyelectrolyte dosage and were not significantly affected as polyelectrolyte dosage increased. Advantages and disadvantages of co-conditioning and dewatering chemical sludge and waste activated sludge were discussed.

  15. Pressurised electro-osmotic dewatering of activated and anaerobically digested sludges: electrical variables analysis.

    Science.gov (United States)

    Citeau, M; Olivier, J; Mahmoud, A; Vaxelaire, J; Larue, O; Vorobiev, E

    2012-09-15

    Pressurised electro-osmotic dewatering (PEOD) of two sewage sludges (activated and anaerobically digested) was studied under constant electric current (C.C.) and constant voltage (C.V.) with a laboratory chamber simulating closely an industrial filter. The influence of sludge characteristics, process parameters, and electrode/filter cloth position was investigated. The next parameters were tested: 40 and 80 A/m², 20, 30, and 50 V-for digested sludge dewatering; and 20, 40 and 80 A/m², 20, 30, and 50 V-for activated sludge dewatering. Effects of filter cloth electric resistance and initial cake thickness were also investigated. The application of PEOD provides a gain of 12 points of dry solids content for the digested sludge (47.0% w/w) and for the activated sludge (31.7% w/w). In PEOD processed at C.C. or at C.V., the dewatering flow rate was similar for the same electric field intensity. In C.C. mode, both the electric resistance of cake and voltage increase, causing a temperature rise by ohmic effect. In C.V. mode, a current intensity peak was observed in the earlier dewatering period. Applying at first a constant current and later on a constant voltage, permitted to have better control of ohmic heating effect. The dewatering rate was not significantly affected by the presence of filter cloth on electrodes, but the use of a thin filter cloth reduced remarkably the energy consumption compared to a thicker one: 69% of reduction energy input at 45% w/w of dry solids content. The reduction of the initial cake thickness is advantageous to increase the final dry solids content. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Radioactive contamination of sewage sludge

    International Nuclear Information System (INIS)

    Soeder, C.J.; Zanders, E.; Raphael, T.

    1986-01-01

    Because of the radioactivity released through the explosion of the nuclear reactor near Chernobyl radionuclides have been accumulated to a significant extent in sewage sludge in the Federal Republic of Germany. This is demonstrated for samples from four activated sludge plants according to a recent recommendation of the German Commission for Radiation Protection, there is until now no reason to deviate from the common practices of sludge disposal or incineration. The degree of radioactive contamination of plant materials produced on farm lands on which sewage sludge is being spread cannot be estimated with sufficient certainty yet. Additional information is required. (orig.) [de

  17. Composting of sewage sludge irradiated

    International Nuclear Information System (INIS)

    Hashimoto, Shoji; Watanabe, Hiromasa; Nishimura, Koichi; Kawakami, Waichiro

    1981-01-01

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

  18. Application of Hydrothermal Treatment to High Concentrated Sewage Sludge for Anaerobic Digestion Process

    OpenAIRE

    M. Orikawa; H. Kamahara; Y. Atsuta; H. Daimon

    2013-01-01

    Tomato and seaweed were produced by utilizing CO2 and heat discharged from power generation using biogas in Toyogawa biomass park, Japan. The biogas was obtained by anaerobic digestion with hydrothermal treatment. The hydrothermal treatment was applied to the high concentrated sewage sludge (22 % total solids (TS) dewatered sludge). The purpose of this study is to clarify the effect of hydrothermal treatment on the qualities of high concentrated sewage sludge, by analyzing particulate organic...

  19. Innovative sewage sludge utilization in Switzerland; Innovative Klaerschlammverwertung in der Schweiz

    Energy Technology Data Exchange (ETDEWEB)

    Greiler, Erwin [oeCompany - Renewable Energy Consulting, Graz (Austria)

    2017-08-01

    ln the nature in millions of years running of coal origin process is technically copied with the socalled hydrothermal carbonization within less hours. As source substrate any biomass can be used practically. ln the case of sewage sludge as the starting substrate, both fresh and sludge dewatering can be used. The advantage of the HTC procedure compared with to conventional sewage sludge utilisation lies, among other things, in the lower energy consumption during the process. Therefore, overall, it is more environmentally friendly.

  20. 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.

  1. The existing state of sewage sludge containing radioactive substances

    International Nuclear Information System (INIS)

    Shirasaki, Makoto; Hisaoka, Natsuki

    2012-01-01

    Radioactive substances were discharged over a wide range from the accident of the Fukushima Daiichi Nuclear Station of Tokyo Electric Power Company. As a result, in sewer system, especially in the combined sewer system that jointly collects rainwater and sewage, radioactive substances accumulated on the surface of urban areas were transferred together with rainwater to sewage plants and accumulated there. In the process of further treatment, radioactive substances were transferred to and concentrated in sewage sludge, and a high concentration of radioactive substances were detected in incineration ash. For this reason, some sewage plants still continuously store dewatered sludge, incinerator ash, etc. This paper introduces the current state of waste treatment from the published data from each local government in Tohoku and Kanto districts. As for the sewer, which is essential as a lifeline, the Ministry of Land, Infrastructure, Transport and Tourism, together with the Japan Sewage Works Association, established 'Investigative Commission on Radioactive Substance Countermeasures in Sewerage System.' This group grasped the damage situation due to radioactive substances, and summarized the measures to be taken by sewage managers, such as the storage method for sewage sludge containing radioactive substances as well as the method for the volume reduction of sewage sludge. (O.A.)

  2. Integral study of sewage sludges

    International Nuclear Information System (INIS)

    1994-01-01

    Sewage sludges are the by-product generated during the treatment process of waste water, and they are conformed by a solid phase which origin is the accumulation of pollutant materials which has been added to water during natural and anthropogenic activities. Its handling is one of the most serious problems faced by water treatment plants which involve the production, gathering, transportation, re utilization and final disposal of sewage sludges. The main purpose of this project is to perform a technical evaluation of the process of sewage sludge irradiation for its possible application as a choice for treatment and final disposal. Irradiation with gammas from Cobalt-60 shows effectiveness in disinfestation of sewage sludges, since they reduce six times the microbial population with a 7 KGy dose. In like manners with doses of 10 KGy is possible to bring down in 70 % the concentration of organic compounds, as well as to eliminate the presence of 6 to 22 organic compounds on samples of sewage sludges. The whole content of this work is presented in six sections: Introduction, Antecedents, Methodology, Conclusions, Suggestions and Bibliography. (Author)

  3. Effects of gamma irradiation on physical-chemical properties and dewatering characteristics of sludges

    International Nuclear Information System (INIS)

    Groneman, A.F.

    1976-01-01

    Separation of solids from liquids is a paramount operation in the processes applied in treating sewage and waste waters. Therfore, studies were undertaken to investigate effects of gamma irradiation on the physical-chemical properties of sludges and the de-watering characteristics of anaerobically digested sludge and aerobically activated sludge. A dose of 300 krad reduced the specific resistance of anaerobically digested sludges from 33 x 10 sec 2 /g to approximately 10 x 10 9 sec 2 /g. This conditioning effect was little influenced by the presence of oxygen or nitrogen. Pasteurization increased the specific resistance to filtration up to 48 x 10 9 sec 2 /g. Dewatering characteristics of raw sludge were not affected by irradiation in the presence of oxygen but a slight conditioning effect was noticed when the sludge was irradiated under deaerated conditions. Experimental evidence indicated that gamma irradiation detached organic substances from the sludge flocks resulting in a decrease of the specific resistance and an increase in the Total Organic Carbon (TOC) and the Chemical Oxygen Demand (COD) in the filtrates. Elutriation reduced but did not eliminate the conditioning effect of gamma irradiation. (author)

  4. Sewage sludge pretreatment and disposal. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    The bibliography contains citations concerning techniques and equipment used in the pretreatment and disposal of sewage sludges. Citations discuss sludge digestion, dewatering, disinfection, stabilization, chlorination, and desulfurization. Topics include pretreatment programs, land disposal, incineration, and waste utilization. Environmental monitoring and protection, federal regulations, and legal aspects are examined. (Contains 50-250 citations and includes a subject term index and title list.)

  5. Agricultural yields of irradiated sewage sludge

    International Nuclear Information System (INIS)

    Magnavacca, Cecilia; Miranda, E.; Sanchez, M.

    1999-01-01

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

  6. Microbiological and physico-chemical studies on irradiated dewatered sludge

    International Nuclear Information System (INIS)

    Hilmy, N.; Suwirma, S.; Harsoyo; Suhadi, F.

    1987-01-01

    Microbiological and physico-chemical studies on irradiated dewatered sludge. Microbiological and physico-chemical dewatered have been carried out and non-irradiated dewatered sludge of Jakarta city, collected during the rainy and dry season. Total bacterial counts of non-irradiated dewatered sludge with water content of around 20%, were found to be about 7x10 8 per g during the rainy season and 7x10 6 up to 1.3x10 8 per g during the dry season, while coliform fecal Streptococcus and Pseudomonas were found to be 1.6x10 4 to 1.0x10 7 , 3x10 5 , and 5x10 3 per g, respectively. No Salmonella, Shigella and Vibrio were detected in all of the samples observed. About 10% of the total number of coliforms were found to be Escherichia coli. A dose of 6 kGy could eliminate the coliform, E. Coli, fecal Streptococcus and Pseudomonas from all of the dewatered sludge observed. The nutrient value of the sludge was sufficient, i.e. total nitrogen content ranged between 1 and 4,42%, phosphorus between 1.55 and 2.36%, and potassium between 0,1 and 0,2% of dry matter. Heavy metal contents were found a little bit high to be applied as animal feed, but it is still acceptable for soil conditioner. Combining 3 months storage at ambient environment and irradiation dose of 2.5 kGy were found to work synergistically to eliminate coliforms and E. Coli from sludge. (author). 8 figs, 17 refs

  7. Effect of hydrothermal treatment temperature on the properties of sewage sludge derived solid fuel

    Directory of Open Access Journals (Sweden)

    Mi Yan

    2015-10-01

    Full Text Available High moisture content along with poor dewaterability are the main challenges for sewage sludge treatment and utilization. In this study, the effect of hydrothermal treatment at various temperature (120-200 ˚C on the properties of sewage sludge derived solid fuel was investigated in the terms of mechanical dewatering character, drying character, calorific value and heavy metal distribution. Hydrothermal treatment (HT followed by dewatering process significantly reduced moisture content and improved calorific value of sewage sludge with the optimum condition obtained at 140˚C. No significant alteration of drying characteristic was produced by HT. Heavy metal enrichment in solid particle was found after HT that highlighted the importance of further study regarding heavy metal behavior during combustion. However, it also implied the potential application of HT on sewage sludge for heavy metal removal from wastewater.

  8. Full-scale performance of selected starch-based biodegradable polymers in sludge dewatering and recommendation for applications.

    Science.gov (United States)

    Zhou, Kuangxin; Stüber, Johan; Schubert, Rabea-Luisa; Kabbe, Christian; Barjenbruch, Matthias

    2018-01-01

    Agricultural reuse of dewatered sludge is a valid route for sludge valorization for small and mid-size wastewater treatment plants (WWTPs) due to the direct utilization of nutrients. A more stringent of German fertilizer ordinance requires the degradation of 20% of the synthetic additives like polymeric substance within two years, which came into force on 1 January 2017. This study assessed the use of starch-based polymers for full-scale dewatering of municipal sewage sludge. The laboratory-scale and pilot-scale trials paved the way for full-scale trials at three WWTPs in Germany. The general feasibility of applying starch-based 'green' polymers in full-scale centrifugation was demonstrated. Depending on the sludge type and the process used, the substitution potential was up to 70%. Substitution of 20-30% of the polyacrylamide (PAM)-based polymer was shown to achieve similar total solids (TS) of the dewatered sludge. Optimization of operational parameters as well as machinery set up in WWTPs is recommended in order to improve the shear stability force of sludge flocs and to achieve higher substitution potential. This study suggests that starch-based biodegradable polymers have great potential as alternatives to synthetic polymers in sludge dewatering.

  9. Rapid thermal conditioning of sewage sludge

    Science.gov (United States)

    Zheng, Jianhong

    Rapid thermal conditioning (RTC) is a developing technology recently applied to sewage sludge treatment. Sludge is heated rapidly to a reaction temperature (up to about 220sp°C) under sufficient pressure to maintain the liquid phase. Reaction is quenched after 10 to 30 seconds when the mixture of sludge and steam pass through a pressure let-down valve. This process reduces the amount of sludge requiring land disposal, eliminates the need for polymer coagulant, improves dewaterability, increases methane production, and further reduces the concentration of pathogens. The odor problem associated with traditional thermal conditioning processes is largely minimized. Ammonia removal is readily integrated with the process. For this research, a pilot unit was constructed capable of processing 90 liters of sludge per hour. Over 22 runs were made with this unit using sludge from New York City Water Pollution Control Plants (WPCP). Sludges processed in this equipment were tested to determine the effect of RTC operating conditions on sludge dewaterability, biodegradability, and other factors affecting the incorporation of RTC into wastewater treatment plants. Dewaterability of thermally conditioned sludge was assessed for cetrifugeability and filterability. Bench scale centrifugation was used for evaluating centrifugeability, pressure filtration and capillary suction time (CST) for filterability. A mathematical model developed for centrifuge dewatering was used to predict the effect of RTC on full scale centrifuge performance. Particle size distribution and solids density of raw and treated PDS were also analyzed. An observed increase in sludge solids density at least partially explains its improved centrifugeability. An investigation of thermally conditioned amino acids showed that the L-isomer is highly biodegradable while the D-isomers are generally less so. Glucose is highly biodegradable, but rapidly becomes refractory as thermal conditioning time is lengthened. This

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

    International Nuclear Information System (INIS)

    Rosopulo, A.; Fiedler, I.; Staerk, H.; Suess, A.; Technische Univ. Muenchen

    1975-01-01

    Analyses of mineral nutrients and trace elements in sewage sludge over a one year period showed that there are relatively small differences in the content of inorganic constituents. In relation to sewage sludge treatment we found a change in the ratio of NH 4 -N : total N after a heat treatment; this means that the ammonium content increased in 70% of the analysed samples compared to untreated sludge. After radiation treatment of sewage sludge no change can be observed up to a pH of 8. With an increase of the pH-value (>= 8) losses of NH- 4 N can be observed. During the dewatering process of sewage sludge - which is influenced by sewage sludge treatment -, potassium, sodium and ammonium are enriched in the filtering water. While there is a decrease of these alkali elements in the dewatered sewage sludge, nearly no change in the other components can be observed. Studying the availability of mineral compounds and trace elements to plants, results are presented of inorganic nutrients and essential or toxic trace elements of sewage sludge and plants. (orig.) [de

  11. Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge

    DEFF Research Database (Denmark)

    Hansen, H.K.; Christensen, Iben Vernegren; Ottosen, Lisbeth M.

    2003-01-01

    . Casagrande's coefficients were determined for the four materials at different water contents. The experiments in this work showed that chalk could be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM by electroosmosis....... The process was not optimised indicating that higher dry matter contents could be achieved by electroosmosis. It was possible to relate Casagrande's coefficient directly to the electroosmotic coefficient obtained by dewatering experiments....

  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. Lipid profiling in sewage sludge.

    Science.gov (United States)

    Zhu, Fenfen; Wu, Xuemin; Zhao, Luyao; Liu, Xiaohui; Qi, Juanjuan; Wang, Xueying; Wang, Jiawei

    2017-06-01

    High value-added reutilization of sewage sludge from wastewater treatment plants (WWTPs) is essential in sustainable development in WWTPs. However, despite the advantage of high value reutilization, this process must be based on a detailed study of organics in sludge. We used the methods employed in life sciences to determine the profile of lipids (cellular lipids, free fatty acids (FFAs), and wax/gum) in five sludge samples obtained from three typical WWTPs in Beijing; these samples include one sludge sample from a primary sedimentation tank, two activated sludge samples from two Anaerobic-Anoxic-Oxic (A2/O) tanks, and two activated sludge samples from two membrane bioreactor tanks. The percentage of total raw lipids varied from 2.90% to 12.3%. Sludge from the primary sedimentation tank showed the highest concentrations of lipid, FFA, and wax/gum and the second highest concentration of cellular lipids. All activated sludge contained an abundance of cellular lipids (>54%). Cells in sludge can from plants, animals, microbes and so on in wastewater. Approximately 14 species of cellular lipids were identified, including considerable high value-potential ceramide (9567-38774 mg/kg), coenzyme (937-3897 mg/kg), and some phosphatidylcholine (75-548 mg/kg). The presence of those lipid constituents would thus require a wider range of recovery methods for sludge. Both cellular lipids and FFAs contain an abundance of C16-C18 lipids at high saturation level, and they serve as good resources for biodiesel production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Where to dispose of the sewage sludge?

    International Nuclear Information System (INIS)

    Beurer, P.; Geering, F.

    2001-01-01

    The 'proper' course for the disposal of sewage sludge is a topic that has continually sparked intense discussion for years. New legal regulations have developed which have significantly changed the disposal structure. Nevertheless, the consumer market of agriculture products has an increasing influence on sewage sludge recycling possibilities. In this report, the changes in sewage sludge disposal within the last ten years and the expected development is pointed out. On account of legal guidelines and of political market influences, the thermal recycling of sewage sludge is considered as the future solution, which should, however, be adapted according to marginal situations. (author)

  15. Effects of different sludge disintegration methods on sludge moisture distribution and dewatering performance.

    Science.gov (United States)

    Jin, Lingyun; Zhang, Guangming; Zheng, Xiang

    2015-02-01

    A key step in sludge treatment is sludge dewatering. However, activated sludge is generally very difficult to be dewatered. Sludge dewatering performance is largely affected by the sludge moisture distribution. Sludge disintegration can destroy the sludge structure and cell wall, so as change the sludge floc structure and moisture distribution, thus affecting the dewatering performance of sludge. In this article, the disintegration methods were ultrasound treatment, K2FeO4 oxidation and KMnO4 oxidation. The degree of disintegration (DDCOD), sludge moisture distribution and the final water content of sludge cake after centrifuging were measured. Results showed that three disintegration methods were all effective, and K2FeO4 oxidation was more efficient than KMnO4 oxidation. The content of free water increased obviously with K2FeO4 and KMnO4 oxidations, while it decreased with ultrasound treatment. The changes of free water and interstitial water were in the opposite trend. The content of bounding water decreased with K2FeO4 oxidation, and increased slightly with KMnO4 oxidation, while it increased obviously with ultrasound treatment. The water content of sludge cake after centrifuging decreased with K2FeO4 oxidation, and did not changed with KMnO4 oxidation, but increased obviously with ultrasound treatment. In summary, ultrasound treatment deteriorated the sludge dewaterability, while K2FeO4 and KMnO4 oxidation improved the sludge dewaterability. Copyright © 2014. Published by Elsevier B.V.

  16. [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.

  17. Environmental and economic life cycle assessment for sewage sludge treatment processes in Japan.

    Science.gov (United States)

    Hong, Jinglan; Hong, Jingmin; Otaki, Masahiro; Jolliet, Olivier

    2009-02-01

    Life cycle assessment for sewage sludge treatment was carried out by estimating the environmental and economic impacts of the six alternative scenarios most often used in Japan: dewatering, composting, drying, incineration, incinerated ash melting and dewatered sludge melting, each with or without digestion. Three end-of-life treatments were also studied: landfilling, agricultural application and building material application. The results demonstrate that sewage sludge digestion can reduce the environmental load and cost through reduced dry matter volume. The global warming potential (GWP) generated from incineration and melting processes can be significantly reduced through the reuse of waste heat for electricity and/or heat generation. Equipment production in scenarios except dewatering has an important effect on GWP, whereas the contribution of construction is negligible. In addition, the results show that the dewatering scenario has the highest impact on land use and cost, the drying scenario has the highest impact on GWP and acidification, and the incinerated ash melting scenario has the highest impact on human toxicity due to re-emissions of heavy metals from incinerated ash in the melting unit process. On the contrary, the dewatering, composting and incineration scenarios generate the lowest impact on human toxicity, land use and acidification, respectively, and the incinerated ash melting scenario has the lowest impact on GWP and cost. Heavy metals released from atmospheric effluents generated the highest human toxicity impact, with the effect of dioxin emissions being significantly lower. This study proved that the dewatered sludge melting scenario is an environmentally optimal and economically affordable method.

  18. Seasonal changes in bacterial counts and radiation-disinfection of sewage sludge

    International Nuclear Information System (INIS)

    Watanabe, Hiroshi; Ito, Hitoshi; Takehisa, Masaaki; Iizuka, Hiroshi.

    1981-01-01

    The effect of radiation on sewage sludge was investigated to disinfect it. The results obtained were as follows: 1. In either activated sludge or digested sludge dewatered by centrifugation, total bacteria and coliforms were up to 3.0 x 10 9 /g and 3.5 x 10 8 /g, respectively. In the activated sludge which was dewatered by a filter-press with calcium oxide and iron chloride, total bacteria were up to 3.0 x 10 5 /g, while coliforms were hardly detected. 2. The fraction of coliforms was somewhat more in centrifuged sludge than in raw sludge. 3. The radiosensitivity of coliforms in raw sludge differed between samples. Namely, some sludge was sterilized with 0.5 Mrad while others were not sterilized even with 1.0 Mrad. On the other hand, coliforms in dewatered sludge were sterilized with 0.5 Mrad without seasonal change, but total bacteria were more radioresistant and more than 13 Mrad was required to reduce it to an undetectable level. From these results it is concluded that the dewatered sludge should be irradiated at 0.5 Mrad to eliminate the coliforms in it. (author)

  19. Supercritical water gasification of sewage sludge: gas production and phosphorus recovery

    NARCIS (Netherlands)

    Acelas Soto, N.Y.; Lopez, D.P.; Brilman, Derk Willem Frederik; Kersten, Sascha R.A.; Kootstra, A.M.J.

    2014-01-01

    In this study, the feasibility of the gasification of dewatered sewage sludge in supercritical water (SCW) for energy recovery combined with P-recovery from the solid residue generated in this process was investigated. SCWG temperature (400 °C, 500 °C, 600 °C) and residence time (15 min, 30 min, 60

  20. Land application of sewage sludge: Pathogen issues

    International Nuclear Information System (INIS)

    Chang, A.C.

    1997-01-01

    Diseases transmitted via the faecal-oral exposure route cause severe gastroenteric disorders, and large numbers of causative organisms are discharged with the faecal matter of infected individuals. For this reason, pathogenic bacteria, viruses, protozoa, or helminths, are always found in sewage sludge. If not properly treated for use in agriculture, sludge can be a source of pathogenic contamination. Radiation is an attractive method to reduce the numbers of microorganisms in sewage sludge. Routine examination for pathogens is not practised nor recommended because complicated and costly procedures are involved. Instead, an indicator organism is usually assayed and enumerated. In this paper, methods are discussed for the investigation of pathogens in sewage sludge. (author)

  1. Disinfection of sewage sludge with gamma radiation

    International Nuclear Information System (INIS)

    1980-01-01

    In the Geiselbullach sewage treatment plant near Munich, sewage irradiation by a 60 Co source is being investigated on a technical scale. 145 m 3 of sewage sludge are irradiated per day and then used as field fertilizer. (orig./HBR) [de

  2. Dewaterability of five sewage sludges in Guangzhou conditioned with Fenton's reagent/lime and pilot-scale experiments using ultrahigh pressure filtration system.

    Science.gov (United States)

    Liang, Jialin; Huang, Shaosong; Dai, Yongkang; Li, Lei; Sun, Shuiyu

    2015-11-01

    Sludge conditioning with Fenton's reagent and lime is a valid method for sludge dewatering. This study investigated the influence of different organic matter content sludge on sludge dewatering and discussed the main mechanism of sludge conditioning by combined Fenton's reagent and lime. The results indicated that the specific resistance to filterability (SRF) of sludge was reduced efficiently by approximately 90%, when conditioned with Fenton's reagent and lime. Through single factor experiments, the optimal conditioning combinations were found. In addition, the relationship between VSS% and consumption of the reagents was detected. Furthermore, it was also demonstrated that the SRF and filtrate TOC values had a significant correlation with VSS% of sludge (including raw and conditioned). The main mechanism of sludge dewatering was also investigated. Firstly, it revealed that the dewaterability of sludge was closely correlated to extracellular polymeric substances (EPS) and bound water contents. Secondly, the results of scanning electron microscopy (SEM) stated that sludge particles were to be smaller and thinner after conditioning. And this structure could easily form outflow channels for releasing free water. Additionally, with the ultrahigh pressure filtration system, the water content of sludge cake conditioned with Fenton's reagent and lime could be reduced to below 50%. Moreover, the economic assessment shows that Fenton's reagent and lime combined with ultrahigh pressure filtration system can be an economical and viable technology for sewage sludge dewatering. Finally, three types of sludge were classified: (1) Fast to dewater; (2) Moderately fast to dewater; (3) Slow to dewater sludge. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Pressurized Fluidized Bed Combustion of Sewage Sludge

    Science.gov (United States)

    Suzuki, Yoshizo; Nojima, Tomoyuki; Kakuta, Akihiko; Moritomi, Hiroshi

    A conceptual design of an energy recovering system from sewage sludge was proposed. This system consists of a pressurized fluidized bed combustor, a gas turbine, and a heat exchanger for preheating of combustion air. Thermal efficiency was estimated roughly as 10-25%. In order to know the combustion characteristics of the sewage sludge under the elevated pressure condition, combustion tests of the dry and wet sewage sludge were carried out by using laboratory scale pressurized fluidized bed combustors. Combustibility of the sewage sludge was good enough and almost complete combustion was achieved in the combustion of the actual wet sludge. CO emission and NOx emission were marvelously low especially during the combustion of wet sewage sludge regardless of high volatile and nitrogen content of the sewage sludge. However, nitrous oxide (N2O) emission was very high. Hence, almost all nitrogen oxides were emitted as the form of N2O. From these combustion tests, we judged combustion of the sewage sludge with the pressurized fluidized bed combustor is suitable, and the conceptual design of the power generation system is available.

  4. 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)

  5. Sewage sludge pasteurization by gamma radiation: financial viability case studies

    Energy Technology Data Exchange (ETDEWEB)

    Swinwood, J.F.; Kotler, J. (Nordion International Inc., Kanata, Ontario (Canada))

    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. 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.

  7. Heavy metals precipitation in sewage sludge

    NARCIS (Netherlands)

    Marchioretto, M.M.; Rulkens, W.H.; Bruning, H.

    2005-01-01

    There is a great need for heavy metal removal from strongly metal-polluted sewage sludges. One of the advantages of heavy metal removal from this type of sludge is the possibility of the sludge disposal to landfill with reduced risk of metals being leached to the surface and groundwater. Another

  8. Effects of heat, radiation, and thermoradiation on the filterability of sewage sludge

    International Nuclear Information System (INIS)

    Carter, C.V.

    1978-01-01

    The effects of heat, radiation and thermoradiation processes on the dewatering properties of raw and primary digested sewage sludges were investigated. These effects were measured by observing the changes in filterability subsequent to treatment. Thermal treatment (40 0 to 95 0 C) of the sewage sludge resulted in decreased filterability. Radiation and thermoradiation treatment increased the filterability, the increase being dose and temperature dependent. These treatment methods are not as effective as chemical additives in increasing the filterability of sewage sludge. The combined use of radiation and organic polymer conditioner shows no significant improvement in the filterability of sewage sludge over the use of polymer alone. There appears to be some interaction; however, it shows no useful synergistic effect

  9. Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, H.K.; Kristensen, I.V.; Ottosen, L.M.; Villumsen, A. [Dept. of Geology and Geotechnical Engineering, The Technical Univ. of Denmark, Lyngby (Denmark)

    2001-07-01

    Electroosmotic dewatering has been tested in laboratory cells for 4 different porous materials: chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge from enzyme production. In all cases it was possible to remove water when passing electric DC current through the material. Casagrande's coefficients for the three materials where determined at different water contents. In the electroosmotic experiments shown in this work chalk can be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM. The process was not optimised indicating that higher dry matter contents could be achieved. (orig.)

  10. Sustainability of Domestic Sewage Sludge Disposal

    Directory of Open Access Journals (Sweden)

    Claudia Bruna Rizzardini

    2014-04-01

    Full Text Available Activated sludge is now one of the most widely used biological processes for the treatment of wastewaters from medium to large populations. It produces high amounts of sewage sludge that can be managed and perceived in two main ways: as a waste it is discharged in landfill, as a fertilizer it is disposed in agriculture with direct application to soil or subjected to anaerobic digestion and composting. Other solutions, such as incineration or production of concrete, bricks and asphalt play a secondary role in terms of their degree of diffusion. The agronomical value of domestic sewage sludge is a proved question, which may be hidden by the presence of several pollutants such as heavy metals, organic compounds and pathogens. In this way, the sustainability of sewage sludge agricultural disposal requires a value judgment based on knowledge and evaluation of the level of pollution of both sewage sludge and soil. The article analyzed a typical Italian case study, a water management system of small communities, applying the criteria of evaluation of the last official document of European Union about sewage sludge land application, the “Working Document on Sludge (3rd draft, 2000”. The report brought out good sewage sludge from small wastewater treatment plants and soils quality suggesting a sustainable application.

  11. REEMISSION OF MERCURY COMPOUNDS FROM SEWAGE SLUDGE DISPOSAL

    OpenAIRE

    Beata Janowska

    2016-01-01

    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 metho...

  12. 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.)

  13. Effect of Sewage Sludge Addition on the Completion of Aerobic Composting of Thermally Hydrolyzed Kitchen Biogas Residue

    OpenAIRE

    Hong-tao Liu; Lu Cai

    2014-01-01

    The composting of thermal-hydrolyzed kitchen biogas residue, either with or without sewage sludge, was compared in this study. The addition of sewage sludge increased and prolonged the temperature to a sufficient level that met the requirements for aerobic composting. Moreover, after mixing the compost materials, oxygen, ammonia, and carbon dioxide levels reverted to those typical of aerobic composting. Finally, increased dewatering, organic matter degradation, and similar mature compost prod...

  14. Dewatering of sludge using the hydrosoft high-pressure process; Entwaessern von Schlaemmen mit dem Hydrosoft-Hochdruckverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Eder, C.; Eder, G. [Christian Eder Technology GbR, Neunkirchen (Germany)

    1999-07-01

    The hydrosoft process permits to dewater sludge, especially also sludge from municipal sewage treatment plant, until it contains a high proportion of dry substance. For existing dewatering systems equipped with the long-lived chamber filter presses, too, the dry matter content of the filter cake can be substantially increased using the hydrosoft process; only the pump system must be retrofitted. As a preliminary measure, tests with mobile pilot plants should be carried out. (orig.) [German] Mit dem Hydrosoft-Verfahren besteht die Moeglichkeit Schlaemme, insbesondere auch Schlaemme aus kommunalen Klaeranlagen, auf hohe Trockensubstanz-Gehalte zu entwaessern. Auch bei bestehenden Entwaesserungsanlagen, die mit den langlebigen Kammerfilterpressen ausgeruestet sind, koennen die Trockensubstanzgehalte der Filterkuchen mit dem Hydrosoft-Verfahren, fuer das dann nur noch das Pumpsystem nachgeruestet werden muss, wesentlich angehoben werden. Vorausgehen sollten jeweils Vorversuche mit mobilen Versuchsanlagen. (orig.)

  15. Locally produced natural conditioners for dewatering of faecal sludge.

    Science.gov (United States)

    Gold, Moritz; Dayer, Pauline; Faye, Marie Christine Amie Sene; Clair, Guillaume; Seck, Alsane; Niang, Seydou; Morgenroth, Eberhard; Strande, Linda

    2016-11-01

    In urban areas of low-income countries, treatment of faecal sludge (FS) is insufficient or non-existent. This results in large amounts of FS being dumped into the environment. Existing treatment technologies for FS, such as settling-thickening tanks and drying beds, are land intensive which is limiting in urban areas. Enhanced settling and dewatering by conditioning was evaluated in order to reduce the treatment footprint (or increase treatment capacity). Conventional wastewater conditioners, such as commercially available lime and polymers, are expensive, and commonly rely on complex supply chains for use in low-income countries. Therefore, the treatment performance of five conditioners which could be produced locally was evaluated: Moringa oleifera seeds and press cake, Jatropha curcas seeds, Jatropha Calotropis leaves and chitosan. M. oleifera seeds and press cake, and chitosan improved settling and dewatering and had a similar performance compared to lime and polymers. Optimal dosages were 400-500 kg M. oleifera/t TS, 300-800 kg lime/t TS and 25-50 kg polymer solution/t TS. In comparison, chitosan required 1.5-3.75 kg/t TS. These dosages are comparable to those recommended for wastewater (sludge). The results indicate that conditioning of FS can reduce total suspended solids (TSS) in the effluent of settling-thickening tanks by 22-81% and reduce dewatering time with drying beds by 59-97%. This means that the area of drying beds could be reduced by 59-97% with end-use as soil conditioner, or 9-26% as solid fuel. Least expensive options and availability will depend on the local context. In Dakar, Senegal, chitosan produced from shrimp waste appears to be most promising.

  16. Radioactive contamination of sewage sludge. Preliminary data

    Energy Technology Data Exchange (ETDEWEB)

    Soeder, C J; Zanders, E; Raphael, T

    1986-01-01

    Because of the radioactivity released through the explosion of the nuclear reactor near Chernobyl radionuclides have been accumulated to a significant extent in sewage sludge in the Federal Republic of Germany. This is demonstrated for samples from four activated sludge plants according to a recent recommendation of the German Commission for Radiation Protection, there is until now no reason to deviate from the common practices of sludge disposal or incineration. The degree of radioactive contamination of plant materials produced on farm lands on which sewage sludge is being spread cannot be estimated with sufficient certainty yet. Additional information is required.

  17. Isolation and Characterization of Polyacrylamide-Degrading Bacteria from Dewatered Sludge

    Directory of Open Access Journals (Sweden)

    Feng Yu

    2015-04-01

    Full Text Available Polyacrylamide (PAM is a water-soluble polymer that is widely used as a flocculant in sewage treatment. The accumulation of PAM affects the formation of dewatered sludge and potentially produces hazardous monomers. In the present study, the bacterial strain HI47 was isolated from dewatered sludge. This strain could metabolize PAM as its sole nutrient source and was subsequently identified as Pseudomonas putida. The efficiency of PAM degradation was 31.1% in 7 days and exceeded 45% under optimum culture condition (pH 7.2, 39 °C and 100 rpm. The addition of yeast extract and glucose improved the bacterial growth and PAM degradation. The degraded PAM samples were analyzed by gel-filtration chromatography, Fourier transform infrared and high-performance liquid chromatography. The results showed that high-molecular-weight PAM was partly cleaved to small molecular oligomer derivatives and part of the amide groups of PAM had been converted to carboxyl groups. The biodegradation did not accumulate acrylamide monomers. Based on the SDS-PAGE and N-terminal sequencing results, the PAM amide groups were converted into carboxyl groups by a PAM-induced extracellular enzyme from the aliphatic amidase family.

  18. grown on soil amended with sewage sludge

    African Journals Online (AJOL)

    DELL

    2Department of Civil Engineering, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria. Corresponding ... Key Words: Sewage sludge, Green amaranth, Phytoextraction, Heavy metals. ..... Wastewater-irrigated Areas of Titagarh,.

  19. Enhancing sewage sludge dewaterability by bioleaching approach with comparison to other physical and chemical conditioning methods.

    Science.gov (United States)

    Liu, Fenwu; Zhou, Jun; Wang, Dianzhan; Zhou, Lixiang

    2012-01-01

    The sewage sludge conditioning process is critical to improve the sludge dewaterability prior to mechanical dewatering. Traditionally, sludge is conditioned by physical or chemical approaches, mostly with the addition of inorganic or organic chemicals. Here we report that bioleaching, an efficient and economical microbial method for the removal of sludge-borne heavy metals, also plays a significant role in enhancing sludge dewaterability. The effects of bioleaching and physical or chemical approaches on sludge dewaterability were compared. The conditioning result of bioleaching by Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans on sludge dewatering was investigated and compared with the effects of hydrothermal (121 degrees C for 2 hr), microwave (1050 W for 50 sec), ultrasonic (250 W for 2 min), and chemical conditioning (24% ferric chloride and 68% calcium oxide; dry basis). The results show that the specific resistance to filtration (SRF) or capillary suction time (CST) of sludge is decreased by 93.1% or 74.1%, respectively, after fresh sludge is conditioned by bioleaching, which is similar to chemical conditioning treatment with ferric chloride and calcium oxide but much more effective than other conditioning approaches including hydrothermal, microwave, and ultrasonic conditioning. Furthermore, after sludge dewatering, bioleached sludge filtrate contains the lowest concentrations of chroma (18 times), COD (542 mg/L), total N (TN, 300 mg/L), NH4(+)-N (208 mg/L), and total P (TP, 2 mg/L) while the hydrothermal process resulted in the highest concentration of chroma (660 times), COD (18,155 mg/L), TN (472 mg/L), NH4(+)-N (381 mg/L), and TP (191 mg/L) among these selected conditioning methods. Moreover, unlike chemical conditioning, sludge bioleaching does not result in a significant reduction of organic matter, TN, and TP in the resulting dewatered sludge cake. Therefore, considering sludge dewaterability and the chemical properties of sludge

  20. Improved waste-activated sludge dewatering using sludge/oil ...

    African Journals Online (AJOL)

    2014-10-07

    Oct 7, 2014 ... 2Dept. of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seongdong-Gu, Seoul 133-791, ... conventional heating methods in chemical reactions is becom- ... the dewaterability of sludge and reduces the organic matter ..... It is unlikely that this technique will be applied in.

  1. Survey of radiation effect on sewage sludge

    International Nuclear Information System (INIS)

    M'selmi, Nadia Ammar

    2005-01-01

    The high nutrient and organic matter contents of sewage sludge make it a useful soil amandment for famers. the presence of heavy metals and pathogens poses a major problem for utilisation of sladge to agriculture land. Radiation is a convenable method of sewage treatment. (author)

  2. Radiation hygienization of raw sewage sludge

    International Nuclear Information System (INIS)

    Shah, M.R.; Lavale, D.S.; Rawat, P.; Benny, P.G.; Sharma, A.K.; Dey, G.R.; Bhave, V.

    2001-01-01

    'Radiation treatment of municipal sewage sludge can achieve resource conservation and recovery objectives. The liquid sludge irradiator of Sludge Hygienization Research Irradiator at Baroda (India) was operated for generating data on treatment of raw sludge containing 3-4 % solids. The plant system was modified for irradiating raw sludge without affecting basic irradiator initially designed to treat digested sludge. Hourly samples were analysed for estimation of disinfection dose requirement. Sand separated from the sludge was used as in-situ dosimeter by making use of its thermoluminescence property. Investigations are being carried out for regrowth of Total Coliforms in the sludge samples from this irradiator. Possibility of inadequate treatment due to geometric configuration of irradiator is being checked. (author)

  3. 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.

  4. Land application of sewage sludge: Pathogen issues

    Energy Technology Data Exchange (ETDEWEB)

    Chang, A C [Department of Soil and Environmental Sciences, Univ. of California at Riverside, Riverside, CA (United States)

    1997-10-01

    Diseases transmitted via the faecal-oral exposure route cause severe gastroenteric disorders, and large numbers of causative organisms are discharged with the faecal matter of infected individuals. For this reason, pathogenic bacteria, viruses, protozoa, or helminths, are always found in sewage sludge. If not properly treated for use in agriculture, sludge can be a source of pathogenic contamination. Radiation is an attractive method to reduce the numbers of microorganisms in sewage sludge. Routine examination for pathogens is not practised nor recommended because complicated and costly procedures are involved. Instead, an indicator organism is usually assayed and enumerated. In this paper, methods are discussed for the investigation of pathogens in sewage sludge. (author). 8 refs, 3 tabs.

  5. Synergetic pretreatment of waste activated sludge by hydrodynamic cavitation combined with Fenton reaction for enhanced dewatering.

    Science.gov (United States)

    Cai, Meiqiang; Hu, Jianqiang; Lian, Guanghu; Xiao, Ruiyang; Song, Zhijun; Jin, Micong; Dong, Chunying; Wang, Quanyuan; Luo, Dewen; Wei, Zongsu

    2018-04-01

    The dewatering of waste activated sludge by integrated hydrodynamic cavitation (HC) and Fenton reaction was explored in this study. We first investigated the effects of initial pH, sludge concentration, flow rate, and H 2 O 2 concentration on the sludge dewaterability represented by water content, capillary suction time and specific resistance to filtration. The results of dewatering tests showed that acidic pH and low sludge concentration were favorable to improve dewatering performance in the HC/Fenton system, whereas optimal flow rate and H 2 O 2 concentration applied depended on the system operation. To reveal the synergism of HC/Fenton treatment, a suite of analysis were implemented: three-dimensional excitation emission matrix (3-DEEM) spectra of extracellular polymeric substances (EPS) such as proteins and polysaccharides, zeta potential and particle size of sludge flocs, and SEM/TEM imaging of sludge morphology. The characterization results indicate a three-step mechanism, namely HC fracture of different EPS in sludge flocs, Fenton oxidation of the released EPS, and Fe(III) re-flocculation, that is responsible for the synergistically enhanced sludge dewatering. Results of current study provide a basis to improve our understanding on the sludge dewatering performance by HC/Fenton treatment and possible scale-up of the technology for use in wastewater treatment plants. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Electron beam disinfection of sewage sludge

    International Nuclear Information System (INIS)

    Hashimoto, Shoji

    1992-01-01

    Electron beam treatment of dehydrated sewage sludge for safe reutilization was performed. Ranges of total bacterial counts and total coliforms in the sludge were from 1.5 x 10 8 to 1.6 x 10 9 and from 2.2 x 10 7 to 1.5 x 10 8 per wet gram, respectively. Total bacterial counts decreased about 5 log cycles after irradiating 5 kGy and irradiation with 2 kGy was enough to kill all coliforms in sewage sludge. The survival curves of total bacteria, obtained by irradiation in oxygen atmosphere, approached to that in nitrogen atmosphere with the increase of sludge thickness. No effects of dose rate and electron energy were found when the sludge layers were thin enough. Continuous disinfection of sewage sludge cake, with the maximum feed rate of 300 kg-sludge/hr, was successfully performed with a Cockcroft-Walton type electron accelerator, a sludge pump and a flat nozzle. (J.P.N.)

  7. Supercritical water gasification of sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Aye, L.; Yamaguchi, D. [Melbourne Univ. International Technologies Centre, Melbourne, Victoria (Australia). Dept. of Civil and Environmental Engineering

    2006-07-01

    Supercritical water gasification (SCWG) is an attractive technology for producing fuels from biomass and waste materials. As a result of greenhouse gas emissions and issues related to local air pollutants, hydrogen production from these renewable energy resources has been gaining in popularity. Disposal of sewage sludge is another environmental problem that have led to severe regulations. Incineration has been one of the most commonly used means of sewage sludge disposal. Thermal gasification produces gaseous fuel, making it a better option over incineration. However, due to its high moisture content, this process is not feasible to make use of sewage sludge directly. In order to analyze SCWG of sewage sludge, it has been determined that equilibrium analysis is most suitable since the maximum achievable amount of hydrogen in a given reacting condition can be estimated. The equilibrium model can be divided into two types of models, namely stoichiometric and non-stoichiometric. This paper presented the results of a study that used a computer program to develop a nonstoichiometric model with the direct Gibbs free energy minimization technique. In addition, various biomass were simulated for comparisons in order to identify if sewage sludge is a potential feedstock for hydrogen production. Last, the effects of reaction pressure and temperature on product distribution were also examined. It was shown that the proposed model is capable of estimating the product distribution at equilibrium. 33 refs., 4 tabs., 6 figs.

  8. Submersible microbial fuel cell for electricity production from sewage sludge

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Olias, Lola Gonzalez; Kongjan, Prawit

    2010-01-01

    A submersible microbial fuel cell (SMFC) was utilized to treatment of sewage sludge and simultaneous generate electricity. Stable power generation (145±5 mW/m2) was produced continuously from raw sewage sludge for 5.5 days. The corresponding total chemical oxygen demand (TCOD) removal efficiency...... of an effective system to treatment of sewage sludge and simultaneous recover energy....

  9. Virological investigations on inadiated sewage sludge

    International Nuclear Information System (INIS)

    Epp, C.

    1980-08-01

    The virusinactivating activity of a Co 60 -irradiation pilot plant at Geiselbullach/Munich was to be examined. We investigated 16 impure sewage water, 15 purified sewage water, 32 raw sladge samples, 62 digested sludge samples before irradiation, 52 digested sludge samples after irradiation and 9 raw sludge samples after irradiation. We completed these investigations by adding poliovaccinevirus type 1 to the digested sludge before irradiation and by adding suspensions of pure virus in MEM + 2% FBS packed in synthetic capsules and mixtures of virus and sludge packed in synthetic capsules to the digested sludge. After the irradiation we collected the capsules and determined the virustiter. The testviruses were poliovaccinevirus type 1, poliowildvirus type 1, echovirus type 6, coxsackie-B-virus type 5, coxsackie-A-virus type 9 and adenovirus type 1. In the field trial the irradiation results were like the laboratory results assuming that the sewage sludge was homogenized enough by digestion and the solid particle concentration was not more than 3%. The D-value was 300-400 krad for enteroviruses and 700 krad for adenovirus. (orig.) [de

  10. Sewage sludge pretreatment and disposal. (Latest citations from the NTIS Bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    The bibliography contains citations concerning techniques and equipment used in the pretreatment processes and disposal of sewage sludges. Topics include resource and energy recovery operations, land disposal, composting, ocean disposal, and incineration. Digestion, dewatering, and disinfection are among the pretreatment processes discussed. Environmental aspects, including the effects on soils, plants, and animals, are also presented. (Contains 250 citations and includes a subject term index and title list.)

  11. Energy recovery from sewage sludge by means of fluidised bed gasification

    International Nuclear Information System (INIS)

    Gross, Bodo; Eder, Christian; Grziwa, Peter; Horst, Juri; Kimmerle, Klaus

    2008-01-01

    Because of its potential harmful impact on the environment, disposal of sewage sludge is becoming a major problem all over the world. Today the available disposal measures are at the crossroads. One alternative would be to continue its usage as fertiliser or to abandon it. Due to the discussions about soil contamination caused by sewage sludge, some countries have already prohibited its application in agriculture. In these countries, thermal treatment is now presenting the most common alternative. This report describes two suitable methods to directly convert sewage sludge into useful energy on-site at the wastewater treatment plant. Both processes consist mainly of four devices: dewatering and drying of the sewage sludge, gasification by means of fluidised bed technology (followed by a gas cleaning step) and production of useful energy via CHP units as the final step. The process described first (ETVS-Process) is using a high pressure technique for the initial dewatering and a fluidised bed technology utilising waste heat from the overall process for drying. In the second process (NTVS-Process) in addition to the waste heat, solar radiation is utilised. The subsequent measures - gasification, gas cleaning and electric and thermal power generation - are identical in both processes. The ETVS-Process and the NTVS-Process are self-sustaining in terms of energy use; actually a surplus of heat and electricity is generated in both processes

  12. Sustainability of Domestic Sewage Sludge Disposal

    OpenAIRE

    Claudia Bruna Rizzardini; Daniele Goi

    2014-01-01

    Activated sludge is now one of the most widely used biological processes for the treatment of wastewaters from medium to large populations. It produces high amounts of sewage sludge that can be managed and perceived in two main ways: as a waste it is discharged in landfill, as a fertilizer it is disposed in agriculture with direct application to soil or subjected to anaerobic digestion and composting. Other solutions, such as incineration or production of concrete, bricks and asphalt play a s...

  13. Influence of nanoparticles on the polymer-conditioned dewatering of wastewater sludges.

    Science.gov (United States)

    Boyle, N J; Evans, G M

    2013-01-01

    The effect of using small-scale, high surface area, nanoparticles to supplement polymer-conditioned wastewater sludge dewatering was investigated. Aerobically digested sludge and waste activated sludge sourced from the Hunter Valley, NSW, Australia, were tested with titanium dioxide nanoparticles. The sludge samples were dosed with the nanoparticles in an attempt to adsorb a component of the charged biopolymer surfactants present naturally in sludge. The sludge was conditioned with a cationic polymer. The dewatering characteristics were assessed by measuring the specific resistance to filtration through a modified time-to-filter testing apparatus. The solids content of the dosed samples was determined by a mass balance and compared to the original solids content in the activated sludge. Test results indicated that nanoparticle addition modified the structure of the sludge and provided benefits in terms of the dewatering rate. The samples dosed with nanoparticles exhibited faster water removal, indicating a more permeable filter cake and hence more permeable sludge. A concentration of 2-4% nanoparticles was required to achieve a noticeable benefit. As a comparison, the sludge samples were also tested with a larger particle size, powdered activated carbon (PAC). It was found that the PAC did provide some minor benefits to sludge dewatering but was outperformed by the nanoparticles. The solids content of the final sludge was increased by a maximum of up to 0.6%. The impact of the order sequence of particles and polymer was also investigated. It was found that nanoparticles added before polymer addition provided the best dewatering performance. This outcome was consistent with current theories and previous research through the literature. An economic analysis was undertaken to confirm the viability of the technology for implementation at a full-scale plant. It was found that, currently, this technology is unlikely to be favourable unless the nanoparticles can be

  14. Co-disposal of sewage sludge and solid wastes-it works

    Energy Technology Data Exchange (ETDEWEB)

    Sussman, D B

    1977-10-01

    The problem of sludge disposal is one of more sludge than ever before, few suitable land disposal or land application sites, the ocean dumping option being phased out, and energy cost so high or supplies so few as to make incineration a questionable endeavor. The energy required to run a wastewater treatment plant and the heat needed to incinerate the sludge may be available in the same community in the form of municipal solid waste. Municipal sludge has a heat value of about 10,000 Btu/lb of dry solids; it is autogenous at>30% solids. Codisposal techniques are discussed which use the energy produced by the combustion of solid waste to dewater the sludge to its autogenous point. One approach is to use sewage sludge incinerators, in many cases already installed at the wastewater treatment plant, and to use the organic portion of solid waste as a fuel to dry, burn, and reduce the volume of the sludge that must ultimately be disposed. A second approach would use a solid waste incinerator, solid waste-fired steam generator, or waterwall combustion unit to burn dewatered sludge. Both approaches are being demonstrated or used. Thermal sludge disposal at wastewater treatment plants normally is carried out in multiple-hearth or fluidized-bed incinerators. The experiences of such plants in the US and Europe are summarized.

  15. PBDEs in Italian sewage sludge and environmental risk of using sewage sludge for land application

    International Nuclear Information System (INIS)

    Cincinelli, Alessandra; Martellini, Tania; Misuri, Lorenza; Lanciotti, Eudes; Sweetman, Andy; Laschi, Serena; Palchetti, Ilaria

    2012-01-01

    Polybrominated diphenyl ethers (PBDEs) were determined in sewage sludge samples collected from eight Italian wastewater treatment plants (WWTPs) between June 2009 and March 2010. Total PBDE concentrations ranged from 158.3 to 9427 ng g −1 dw, while deca-BDE (BDE-209) (concentrations ranging from 130.6 to 9411 ng g −1 dw) dominated the congener profile in all the samples, contributing between 77% and 99.8% of total PBDE. The suitability of using a magnetic particle enzyme-linked immunoassay (ELISA) to analyse PBDEs in sewage sludge was also tested. The ELISA results, expressed as BDE-47 equivalents, were well correlated with those obtained by GC–NCI–MS, with correlation coefficients (r 2 ) of 0.899 and 0.959, depending on the extraction procedure adopted. The risk assessment of PBDEs in sewage sludge addressed to land application was calculated. PEC soil values compared to the relative PNEC soil for penta and deca-BDE suggests that there is a low risk to the soil environment. - Highlights: ► PBDEs in sewage sludge were determined in eight Italian WWTPs for the first time. ► PBDEs concentrations showed differences between the eight investigated WWTPs. ► Deca-BDE (BDE-209) was the dominant congener in all samples. ► The suitability of using ELISA method to analyse PBDEs in sewage sludge was tested. ► The risk assessment of using sewage sludge for land application was evaluated. - Determination of PBDEs in sewage sludge by GC–NCI–MS and ELISA test and risk assessment when sewage sludge is used for land application.

  16. Phosphorus recovery from sewage sludge char ash

    NARCIS (Netherlands)

    Atienza-Martinez, M.; Gea, G.; Arauzo, J.; Kersten, Sascha R.A.; Kootstra, A.M.J.

    2014-01-01

    Phosphorus was recovered from the ash obtained after combustion at different temperatures (600 °C, 750 °C and 900 °C) and after gasification (at 820 °C using a mixture of air and steam as fluidising agent) of char from sewage sludge fast pyrolysis carried out at 530 °C. Depending on the leaching

  17. Feasibility of bioleaching combined with Fenton oxidation to improve sewage sludge dewaterability.

    Science.gov (United States)

    Liu, Changgeng; Zhang, Panyue; Zeng, Chenghua; Zeng, Guangming; Xu, Guoyin; Huang, Yi

    2015-02-01

    A novel joint method of bioleaching with Fenton oxidation was applied to condition sewage sludge. The specific resistance to filtration (SRF) and moisture of sludge cake (MSC) were adopted to evaluate the improvement of sludge dewaterability. After 2-day bioleaching, the sludge pH dropped to about 2.5 which satisfied the acidic condition for Fenton oxidation. Meanwhile, the SRF declined from 6.45×10(10) to 2.07×10(10) s2/g, and MSC decreased from 91.42% to 87.66%. The bioleached sludge was further conditioned with Fenton oxidation. From an economical point of view, the optimal dosages of H2O2 and Fe2+ were 0.12 and 0.036 mol/L, respectively, and the optimal reaction time was 60 min. Under optimal conditions, SRF, volatile solids reduction, and MSC were 3.43×10(8) s2/g, 36.93%, and 79.58%, respectively. The stability and settleability of sewage sludge were both improved significantly. Besides, the results indicated that bioleaching-Fenton oxidation was more efficient in dewatering the sewage sludge than traditional Fenton oxidation. The sludge conditioning mechanisms by bioleaching-Fenton oxidation might mainly include the flocculation effects and the releases of extracellular polymeric substances-bound water and intercellular water. Copyright © 2014. Published by Elsevier B.V.

  18. Cs-137 for irradiation of sewage sludge

    International Nuclear Information System (INIS)

    Lessel, T.

    1986-01-01

    Since 1973, the Geiselbullach sewage treatment works have been continuously operating their first system for gamma irradiation of sewage sludge. Within the framework of a German-American agreement, nine Cs-137 sources with a total activity of 56.000 Ci have been made available to the works free of charge in 1983, in order to test in practice and to demonstrate the applicability of these radiation sources in comparison to the Co-60 sources exclusively used up to then. This first study on the applicability of Cs-137 as a radiation source for sewage sludge treatment revealed no findings or effects speaking against Cs-137 as a radiation source for this purpose. (orig./RB) [de

  19. Sewage sludge irradiators: Batch and continuous flow

    International Nuclear Information System (INIS)

    Lavale, D.S.; George, J.R.; Shah, M.R.; Rawat, K.P.

    1998-01-01

    The potential threat to the environment imposed by high pathogenic organism content in municipal wastewater, especially the sludge and the world-wide growing aspirations for a cleaner, salubrious environment have made it mandatory for the sewage and sludge to undergo treatment, prior to their ultimate disposal to mother nature. Incapabilities associated with the conventional wastewater treatments to mitigate the problem of microorganisms have made it necessary to look for other alternatives, radiation treatment being the most reliable, rapid and environmentally sustainable of them. To promote the use of radiation for the sludge hygienization, Department of Atomic Energy has endeavoured to set up an indigenous, Sludge Hygienization Research Irradiator (SHRI) in the city of Baroda. Designed for 18.5 PBq of 60 Co to disinfect the digested sludge, the irradiator has additional provision for treatment of effluent and raw sewage. From engineering standpoint, all the subsystems have been functioning satisfactorily since its commissioning in 1990. Prolonged studies, spanning over a period of six years, primarily focused on inactivation of microorganism revealed that 3 kGy dose of gamma radiation is adequate to make the sludge pathogen and odour-free. A dose of 1.6 kGy in raw sewage and 0.5 kGy in effluent reduced coliform counts down to the regulatory discharge limits. These observations reflect a possible cost-effective solution to the burgeoning problem of surface water pollution across the globe. In the past, sub 37 PBq 60 Co batch irradiators have been designed and commissioned successfully for the treatment of sludge. Characterized with low dose delivery rates they are well-suited for treating low volumes of sludge in batches. Some concepts of continuous flow 60 Co irradiators having larger activities, yet simple and economic in design, are presented in the paper

  20. 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.

  1. Sanitizing effects of sewage sludge irradiation treatment

    International Nuclear Information System (INIS)

    Zhao Yongfu

    2005-01-01

    A large quantity of pathogenic organisms were found in sewage sludge. An investigation was carried out on the relationship in the chain of sludge-soil-vegetable between the survival of pathogenic organisms and the irradiation dosage. After irradiation with 5-6 kGy, coliform group reduced 3 log cycles, and ascarid ova were completely eliminated with a dose of 1 kGy, making the water matched the standard quality of irrigating water. In the soil applied with irradiated sewage sludge, the total bacteria and coliforms group count reduced to one tenth, and alive ascarid ova was not detected. The coliform group on the Chinese cabbage was extremely low and reached the standard of fresh eating. (authors)

  2. Combustion characteristics of biodried sewage sludge.

    Science.gov (United States)

    Hao, Zongdi; Yang, Benqin; Jahng, Deokjin

    2018-02-01

    In this study, effects of biodrying on the characteristics of sewage sludge and the subsequent combustion behavior were investigated. 7-Day of biodrying removed 49.78% of water and 23.17% of VS initially contained in the sewage sludge and increased lower heating value (LHV) by 37.87%. Meanwhile, mass contents of C and N decreased from 36.25% and 6.12% to 32.06% and 4.82%, respectively. Surface of the biodried sewage sludge (BDSS) appeared granulated and multi-porous, which was thought to facilitate air transfer during combustion. According to thermogravimetric (TG) analysis coupled with mass spectrometer (MS) with a heating rate of 10 °C/min from 35 °C to 1000 °C, thermally-dried sewage sludge (TDSS) and BDSS lost 74.39% and 67.04% of the initial mass, respectively. In addition, combustibility index (S) of BDSS (8.67 × 10 -8  min -2  K -3 ) was higher than TDSS. TG-MS analyses also showed that less nitrogenous gases were generated from BDSS than TDSS. It was again showed that the average CO and NO concentrations in exit gas from isothermal combustion of BDSS were lower than those from TDSS, especially at low temperatures (≤800 °C). Based on these results, it was concluded that biodrying of sewage sludge was an energy-efficient water-removal method with less emission of air pollutants when BDSS was combusted. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. [Improvement of municipal sewage sludge dewaterability by bioleaching: a pilot-scale study with sequence batch reaction model].

    Science.gov (United States)

    Liu, Fen-Wu; Zhou, Li-Xiang; Zhou, Jun; Jiang, Feng; Wang, Dian-Zhan

    2011-07-01

    To observe the bioleaching effect on sewage sludge dewaterability, three consecutive batch bioleaching experiments were conducted through a bioleaching bio-reactor with 700 L of working volume. Subsequently, the bioleached sludge was dewatered by using chamber filter press. The results show that the 1st batch bioleaching process can be finished within 90 hours if the aeration amount was 1.2 m3/h with the 1: 15 mixing ratio of bioleached sludge to raw sludge. The pH of sludge declines from initial 6.11 to 2.33 while ORP increased from initial -134 mV to finial 507 mV. The specific resistance to filtration (SRF) of the tested sludge was decreased from original 1.00 x 10(13) m/kg to final 0.09 x 10(13) m/kg after bioleaching. For the subsequent two batch trials, the bioleaching process can be finished in 40 hours and 46 hours, respectively. Likewise, sludge SRF is also significantly decreased to 0.19 x 10(13) m/kg and 0.36 x 10(13) m/kg if the mixing ratio of bioleached sludge to fresh sludge is 1:1 although the microbial nutrient substance dosage is reduced by 25% and 50% for 2nd, and 3rd batch experiments, respectively. The harvested bioleached sludge from three batch trails is dewatered by chamber filter press with 0.3-0.4 MPa working pressure for 2 hours. It is found that the moisture of dewatered sludge cake can be reduced to 58%, and that the dewatered sludge cake is of khaki appearance and didn't emit any offensive odor. In addition, it is also observes that sludge organic matter only changed a bit from 52.9% to 48.0%, but 58% of sludge-borne Cu and 88% of sludge-borne Zn can be removed from sludge by bioleaching process. Therefore, dual goals for sludge-borne heavy metal removal and sludge dewatering of high efficiency can be achieved simultaneously through the approach mentioned above. Therefore, bioleaching technique is of great engineering application for the treatment of sewage sludge.

  4. Anaerobic co-digestion of sewage sludge and molasses

    Science.gov (United States)

    Kalemba, Katarzyna; Barbusiński, Krzysztof

    2017-11-01

    The efficiency of simultaneous digestion of sewage sludge and by-product of refining sugar beets (molasses) was investigated. The study was conducted for 28 days under mesophilic conditions. 0.5%, 1%, 1.5%, 2% and 3% (m/m) of molasses was added to the mixture of sludge. The result of the study showed that addition of molasses had positive effect the biogas production. The biggest biogas yield was achieved in sample with 0.5% of molasses (95.69 mL/g VS). In this sample biogas production increased by 21% in comparison with reference sample (without molasses). The biggest methane content (73%) was also observed in the sample with 0.5% of molasses. For comparison in reference sample was produced biogas with 70% content of methane. The dose over 0.5% of molasses caused inhibition of fermentation process. The minimal degree (38%) of degradation of organic matter was achieved in reference sample (38.53%) and in sample with 0.5% of molasses (39.71%) but in other samples was in the range of 35.61-36.76 % (from 3% to 1%, respectively). Digestion process have adverse effect on dewatering properties of sludge. Before co-digestion capillary suction time was from 31 s to 55 s, and after process increased from 36 s to 556 s (from 0% to 3% of molasses, respectively).

  5. Radionuclides in sewage sludge and problems of use and disposal

    International Nuclear Information System (INIS)

    Schneider, P.; Tiefenbrunner, F.; Dierich, M.P.; Brunner, P.

    1987-01-01

    In a sewage plant with radioactive contaminated sewage an accumulation of radionuclide in the sewage sludge was to be found. The specific activities are in inverse proportion to the water content of the sewage sludge, the dehydrated sewage sludge shows the highest specific activities. These enriched radionuclides seem to be absorbed from the sludge. Yet they can be utilized by plants. This was demonstrated in experiments with Trifolium repens and Secale cereale, where the rate of absorption amounted 15-33% (inCi/kg dry weight plant:nCi/kg dry weight soil X 100) (transfer factors). This is why fertilization with radioactive contaminated sewage sludge seems to cause problems. In further experiments an extraction of radionuclides from ashed sewage sludge was shown. By acidifying the mobile phasis an increase in radioactivity in the eluated fractions was achieved. (orig./HP) [de

  6. 40 CFR 503.7 - Requirement for a person who prepares sewage sludge.

    Science.gov (United States)

    2010-07-01

    ... sewage sludge. 503.7 Section 503.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SEWAGE SLUDGE STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE General Provisions § 503.7 Requirement for a person who prepares sewage sludge. Any person who prepares sewage sludge shall ensure that the...

  7. 40 CFR Appendix A to Part 503 - Procedure To Determine the Annual Whole Sludge Application Rate for a Sewage Sludge

    Science.gov (United States)

    2010-07-01

    ... Whole Sludge Application Rate for a Sewage Sludge A Appendix A to Part 503 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SEWAGE SLUDGE STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE Pt... a Sewage Sludge Section 503.13(a)(4)(ii) requires that the product of the concentration for each...

  8. Types and treatment of sewage sludges: Practice in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Tabasaran, M.O.

    1975-01-01

    The sludge that is formed by the various processes in the sewage treatment plant consists mainly of water with a small amount of organic and inorganic suspended solids. It contains pathogenic agents and biological inhibitors, and must be prepared and brought into a form where it is less dangerous to the environment. The de-watering of the sludge is the first step in sludge handling. The solids content of the raw sludge, which is usually between 5 and 10%, can be increased by gravity thickening to 15%, by centrifuging or straining-band-pressing up to 30%, and by pressure-filtration up to 40%. The process of drying enables a substance with almost no moisture to be obtained. Generally the sludge will be either mixed before de-watering with coagulation agencies, or preheated, or its colloidal components biochemically oxidized in order to accelerate the withdrawal of the water. One of the most common methods of disposal is the transport of sludge to a land filling, usually together with the solid refuse of the community. For this purpose the moisture content of the sludge should not be more than 60 to 70 percent. The disposal of sludge into the sea can be practised in coastal towns, but the ecological effects of this kind of sludge removal are still disputed. More expedient is the agricultural utilization of sludge, particularly if the sludge is composted together with a carbon carrier such as city refuse which would make it a very suitable soil improver. In the Federal Republic of Germany the wet oxidation of sludge is applied in a few cases. The most common process is anaerobic alkaline digestion. The incineration of sludge is more economical than drying, but still too, expensive in comparison with other approved processes. (author)

  9. 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 ...

  10. The possibility of using a magnetic field for the conditioning of sewage sludge

    Directory of Open Access Journals (Sweden)

    Kamila Natalia Hrut

    2018-04-01

    Full Text Available The purpose of the work was to determine the applicability of the magnetic field for the conditioning of the sewage sludge prepared by the dual chemical method with using PIX 113 iron coagulate, and 2 types of organic polyelectrolytes: Superfloc C-494, and Superfloc C-496. In order to assess the impact of process parameters (flow rate and flow direction through the coil, tests were conducted in several research combinations differing in the method of preparation of sludge, the flow direction and flow rate through the solenoid. The analyses were divided into two stages, differing in the applied polyelectrolyte. In order to determine the changes of susceptibility to dewatering, the capillary suction time test, specific resistance to filtration and the final hydrating of the filter cake were used. The assessment of the quality of the leachates was made on the basis of the chemical oxygen demand values. The most beneficial effects of the magnetic field effect were achieved for the combination with the Superfloc C-494 polymer, and flow through the solenoid towards S-N at rate 1.0 L/min. The results shows that the influence of the magnetic field on the susceptibility to dewatering of the sludge is variable, dependent on the flow direction and flow rate of sludge through the coil, as well as on the type of conditioning agent. In order to be able to unequivocally determine the possibility of using a magnetic field for the conditioning of sewage sludge, further research is necessary.

  11. [Effect of different sludge retention time (SRT) on municipal sewage sludge bioleaching continuous plug flow reaction system].

    Science.gov (United States)

    Liu, Fen-Wu; Zhou, Li-Xiang; Zhou, Jun; Jiang, Feng; Wang, Dian-Zhan

    2012-01-01

    A plug-flow bio-reactor of 700 L working volume for sludge bioleaching was used in this study. The reactor was divided into six sections along the direction of the sludge movement. Fourteen days of continuous operation of sludge bioleaching with different sludge retention time (SRT) under the condition of 1.2 m3 x h(-1) aeration amount and 4 g x L(-1) of microbial nutritional substance was conducted. During sludge bioleaching, the dynamic changes of pH, DO, dewaterability (specific resistance to filtration, SRF) of sewage sludge in different sections were investigated in the present study. The results showed that sludge pH were maintained at 5.00, 3.00, 2.90, 2.70, 2.60 and 2.40 from section 1 to section 6 and the SRF of sludge was drastically decreased from initial 0.64 x 10(13) m x kg(-1) to the final 0.33 x 10(13) m x kg(-1) when bioleaching system reached stable at hour 72 with SRT 2.5d. In addition, the sludge pH were maintained at 5.10, 4.10, 3.20, 2.90, 2.70 and 2.60, the DO value were 0.43, 1.47, 3.29, 4.76, 5.75 and 5.88 mg x L(-1) from section 1 to section 6, and the SRF of sludge was drastically decreased from initial 0.56 x 10(13) to the final 0.20 x 10(13) m x kg(-1) when bioleaching system reached stable at hour 120 with SRT 2 d. The pH value was increased to 3.00 at section 6 at hour 48 h with SRT 1.25 d. The bioleaching system imbalanced in this operation conditions because of the utilization efficiency of microbial nutritional substance by Acidibacillus spp. was decreased. The longer sludge retention time, the easier bioleaching system reached stable. 2 d could be used as the optimum sludge retention time in engineering application. The bioleached sludge was collected and dewatered by plate-and-frame filter press to the moisture content of dewatered sludge cake under 60%. This study would provide the necessary data to the engineering application on municipal sewage sludge bioleaching.

  12. A microbiological study on sewage sludge treatment

    International Nuclear Information System (INIS)

    Sermkiattipong, Ngamnit; Ito, Hitoshi; Hashimoto, Shoji.

    1990-09-01

    Isolation and identification of salmonellae in sewage sludge cake and radiation sensitivities of the isolated strains were studied. Disinfection of the sludge by heat or radiation and effect of such treatment on composting were also carried out. Five groups of O-antigen and seven serotypes of salmonellae were identified from the sludge cakes. D 10 values of the salmonellae in phosphate buffer were ranged from 0.16 to 0.22 kGy and those in sludge were about three times larger. Total bacterial counts and coliforms in the sludges were determined to be 4.6 x 10 7 - 5.1 x 10 9 and 1.3 x 10 5 - 1.1 x 10 9 colony forming unit (cfu/g). After irradiation at 20 kGy by gamma ray or electron beam, decrease of total bacterial count was 5 - 7 log cycles and a dose of 5 kGy was enough to eliminate all of the coliforms. Coliforms decreased rapidly by heating at 65degC, but only one log cycle decrease was observed in total bacterial count. By heating at 100degC, total bacterial count decreased rapidly. Two peaks were observed in CO 2 evolution curves of radiation disinfected sludge composting, but only one peak in heat disinfected sludge composting. (author)

  13. Stabilization/solidification of sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Boura, Panagiota; Katsioti, Margarita; Tsakiridis, Petros; Katsiri, Alexandra

    2003-07-01

    The main objective of this work is to investigate a viable alternative for the final disposal of sewage sludge from urban wastewater treatment plants by its use as an additive in developing new construction materials. For this purpose, several mixtures of sludge- cement and sludge-cement and jarosite/alunite precipitate were prepared. Jarosite/alunite precipitate is a waste product of a new hydrometallurgical process. Two kinds of sludge were used: primary sludge from Psyttalia Wastewater Treatment Plant, which receives a considerable amount of industrial waste, and biological sludge from Metamorphosi Wastewater Treatment Plant. Various percentages of these sludges were stabilized/solidified with Portland cement and Portland cement with jarosite/alunite. The specimens were tested by determination of compressive strength according to the methods described by European Standard EN 196. X-Ray Diffraction (XRD) analysis as well as Thermogravimetry-Differential Thermal Analysis (TG-DTA) were used to determine the hydration products in 28 days. Furthermore, Toxicity Characteristic Leaching Procedure test for heavy metals (TCLP), were carried out in order to investigate the environmental compatibility of these new materials. (author)

  14. Joint stabilization of sewage sludge and separated manure fluid. Treatment and utilization of manure. Final report; Gemeinsame Stabilisierung von Klaerschlamm und separierter Guellefluessigkeit. Guellebehandlung und -verwertung. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, W.F.; Kolisch, G.

    1994-12-01

    As an alternative to separate manure processing, anaerobic stabilization of surplus manure and sewage sludge in combination is possible at municipal sewage treatment plants. Subsequently to the removal of solids, pig manure is fed into existing digesters. The process concept comprises the following partial steps: preliminary treatment of crude manure, anarobic stabilization of the separated manure fluid, biological nitrogen elimination from the digested mixture of sewage sludge and manure, and dewatering of the mixed sludge in the dewatering systems of the sewage treatment plant. (orig./SR) [Deutsch] Eine Alternative zu den Verfahren einer separaten Guelleaufbereitung stellt die gemeinsame anaerobe Stabilisierung von Ueberschussguelle und Klaerschlamm auf kommunalen Klaeranlagen dar, die eine Einspeisung feststoffseparierter Schweineguelle in bereits vorhandene Faulbehaelter vorsieht. Das Verfahrenskonzept besteht aus den Teilschritten Vorseparierung der Rohguelle, anaerobe Stabiliserung der separierten Guellefluessigkeit, biologische Stickstoffelimination aus dem ausgefaulten Klaerschlamm-Guelle-Gemisch sowie Entwaesserung der Mischschlaemme auf den Entwaesserungsaggregaten der Klaeranlage. (orig./SR)

  15. 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.

  16. Submersible microbial fuel cell for electricity production from sewage sludge

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Olias, Lola Gonzalez; Kongjan, Prawit

    2011-01-01

    A submersible microbial fuel cell (SMFC) was utilized to treat sewage sludge and simultaneously generate electricity. Stable power generation (145± 5 mW/m2, 470 Ω) was produced continuously from raw sewage sludge for 5.5 days. The maximum power density reached 190±5 mW/m2. The corresponding total...... system to treat sewage sludge and simultaneously recover energy....

  17. Electro-dewatering of wastewater sludge: influence of the operating conditions and their interactions effects.

    Science.gov (United States)

    Mahmoud, Akrama; Olivier, Jérémy; Vaxelaire, Jean; Hoadley, Andrew F A

    2011-04-01

    Electric field-assisted dewatering, also called electro-dewatering (EDW), is a technology in which a conventional dewatering mechanism such a pressure dewatering is combined with electrokinetic effects to realize an improved liquid/solids separation, to increase the final dry solids content and to accelerate the dewatering process with low energy consumption compared to thermal drying. The application of these additional fields can be applied to either or both dewatering stages (filtration and/or compression), or as a pre-or post-treatment of the dewatering process. In this study, the performance of the EDW on wastewater sludge was investigated. Experiments were carried out on a laboratory filtration/compression cell, provided with electrodes, in order to apply an electrical field. The chosen operating conditions pressure (200-1200 kPa) and voltage (10-50 V) are sufficient to remove a significant proportion of the water that cannot be removed using mechanical dewatering technologies alone. A response surface methodology (RSM) was used to evaluate the effects of the processing parameters of EDW on (i) the final dry solids content, which is a fundamental dewatering parameter and an excellent indicator of the extent of EDW and (ii) the energy consumption calculated for each additional mass of water removed. A two-factor central composite design was used to establish the optimum conditions for the EDW of wastewater sludge. Experiments showed that the use of an electric field combined with mechanical compression requires less than 10 and 25% of the theoretical thermal drying energy for the low and moderate voltages cases, respectively. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  18. Effect of lime addition during sewage sludge treatment on characteristics of resulting SSA when it is used in cementitious materials.

    Science.gov (United States)

    Vouk, D; Nakic, D; Štirmer, N; Baricevic, A

    2017-02-01

    Final disposal of sewage sludge is important not only in terms of satisfying the regulations, but the aspect of choosing the optimal wastewater treatment technology, including the sludge treatment. In most EU countries, significant amounts of stabilized and dewatered sludge are incinerated, and sewage sludge ash (SSA) is generated as a by product. At the same time, lime is one of the commonly used additives in the sewage sludge treatment primarily to stabilize the sludge. In doing so, the question arose how desirable is such addition of lime if the sludge is subsequently incinerated, and the generated ash is further used in the production of cementitious materials. A series of mortars were prepared where 10-20% of the cement fraction was replaced by SSA. Since all three types of analyzed SSA (without lime, with lime added during sludge stabilization and with extra lime added during sludge incineration) yielded nearly same results, it can be concluded that if sludge incineration is accepted solution, lime addition during sludge treatment is unnecessary even from the standpoint of preserving the pozzolanic properties of the resulting SSA. Results of the research carried out on cement mortars point to the great possibilities of using SSA in concrete industry.

  19. Physical, chemical and dewatering characteristics of Ba/RaSO4 sludges from uranium milling

    International Nuclear Information System (INIS)

    Skeaff, J.M.; Campbell, H.W.

    1980-01-01

    There is concern that long-term environmental pollution caused by radionuclide-bearing acid drainage could occur upon the abandonment of uranium tailings areas. One source of dissolved radionuclides could be the Ba/RaSO 4 sludges formed in most tailings ponds. Prior to discharge to open watercourses, uranium tailings decants are usually treated with barium chloride to coprecipitate dissolved radium. The resulting sludge is allowed to settle in ponds, the size and retention time of which will depend on the mine site. It may be necessary for environmental reasons to remove these sludges for permanent disposal. CANMET has awarded a contract to Kilborn Ltd. of Toronto to study methods for the recovery and dewatering of these sludges. To provide data for the Kilborn contract on the physical, chemical and dewatering of Ba/RaSO 4 sludges presently being produced at uranium mine/mill sites, samples were taken from the operational settling ponds at Rio Algom Mines Ltd., Elliot Lake. Dewatering characterization has also been conducted on two pilot plant facility sludges, one produced at the Wastewater Technology Centre's pilot plant at Rio Algom Mines, and the other from the pilot scale settling ponds designed by James F. MacLaren Ltd. for Rio Algom. The chemical and radionuclide analyses for the CANMET sludge are also reported

  20. Possibility of sludge conditioning and dewatering with rice husk biochar modified by ferric chloride.

    Science.gov (United States)

    Wu, Yan; Zhang, Panyue; Zhang, Haibo; Zeng, Guangming; Liu, Jianbo; Ye, Jie; Fang, Wei; Gou, Xiying

    2016-04-01

    Rice husk biochar modified by FeCl3 (MRB-Fe) was used to enhance sludge dewaterability in this study. MRB-Fe preparation conditions and dosage were optimized. Mechanisms of MRB-Fe improving sludge dewaterability were investigated. The optimal modification conditions were: FeCl3 concentration, 3mol/L; ultrasound time, 1h. The optimal MRB-Fe dosage was 60% DS. Compared with raw sludge, the sludge specific resistance to filtration (SRF) decreased by 97.9%, the moisture content of sludge cake decreased from 96.7% to 77.9% for 6min dewatering through vacuum filtration under 0.03MPa, the SV30% decreased from 96% to 60%, and the net sludge solids yield (YN) increased by 28 times. Positive charge from iron species on MRB-Fe surface counteracted negative charge of sludge flocs to promote sludge settleability and dewaterability. Meanwhile, MRB-Fe kept a certain skeleton structure in sludge cake, making the moisture pass through easily. Using MRB-Fe, therefore, for sludge conditioning and dewatering is promising. Copyright © 2016. Published by Elsevier Ltd.

  1. Composting of gamma-radiation disinfected sewage sludge

    International Nuclear Information System (INIS)

    Kawakami, W.; Hashimoto, S.; Watanabe, H.; Nishimura, K.; Watanabe, H.; Ito, H.; Takehisa, M.

    1981-01-01

    The composting of radiation disinfected sewage sludge has been studied since 1978, aiming to present a new process of sludge composting for agricultural uses. This process is composed of two steps: irradiation step to disinfect sludge, and composting step to remove odor and easily decomposable organics in sludge. In this paper, the gamma-irradiation effect on sludge cake and composting condition of irradiated sludge are discussed. (author)

  2. Sewage sludge - What can be done with it?

    International Nuclear Information System (INIS)

    Beurer, P.; Geering, F.

    2002-01-01

    This article presents a review of the state-of-the-art in the disposal of the sewage sludge that is left over after treatment of wastewater. Also, developments over the past ten years both in market structures and in legislation are discussed and future developments are reviewed. On account of legislation and political influences on the market, the thermal exploitation of sewage sludge is looked at in depth. The ecological and economic aspects of sewage sludge disposal are examined and the costs of different methods of sewage sludge treatment are compared. Various methods of disposal including dumping, composting, incineration in cement ovens, coal-fired power stations and waste incineration facilities are discussed, as is burning in special sludge incineration plant. A prognosis is made on the development of sewage sludge quantities for Germany, Switzerland and Austria over the next years

  3. Vancomycin resistant enterococci (VRE in Swedish sewage sludge

    Directory of Open Access Journals (Sweden)

    Aspan Anna

    2009-05-01

    Full Text Available Abstract Background Antimicrobial resistance is a serious threat in veterinary medicine and human healthcare. Resistance genes can spread from animals, through the food-chain, and back to humans. Sewage sludge may act as the link back from humans to animals. The main aims of this study were to investigate the occurrence of vancomycin resistant enterococci (VRE in treated sewage sludge, in a Swedish waste water treatment plant (WWTP, and to compare VRE isolates from sewage sludge with isolates from humans and chickens. Methods During a four month long study, sewage sludge was collected weekly and cultured for VRE. The VRE isolates from sewage sludge were analysed and compared to each other and to human and chicken VRE isolates by biochemical typing (PhenePlate, PFGE and antibiograms. Results Biochemical typing (PhenePlate-FS and pulsed field gel electrophoresis (PFGE revealed prevalence of specific VRE strains in sewage sludge for up to 16 weeks. No connection was found between the VRE strains isolated from sludge, chickens and humans, indicating that human VRE did not originate from Swedish chicken. Conclusion This study demonstrated widespread occurrence of VRE in sewage sludge in the studied WWTP. This implies a risk of antimicrobial resistance being spread to new farms and to the society via the environment if the sewage sludge is used on arable land.

  4. 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.

  5. Experiments as to the influence of heat recovery from a bioreactor on sewage sludge disinfecting

    Energy Technology Data Exchange (ETDEWEB)

    Tarjanyi, J.; Strauch, D.; Philipp, W.

    The influence of heat recovery on the disinfecting effect of composting of sewage sludge in a bio-reactor (in-vessel-composting) was investigated in a reactor type Weiss-system Kneer. As test agents 3 different serovars of salmonella, Parvo- and Poliovirus and eggs of Ascaris suum were used. The experiments were done in a reactor which was fed with dewatered municipal sewage sludge mixed with waste-paper as C-carrier for better composting. Even under winter conditions the test agents were inactivated within the time which is characteristic for the passage of the composting material through the plug-flow reactor. These results cannot simply be applied without further investigation to other reactors of the same type but with different ways of operation. (orig.)

  6. Use of sewage sludge and coconut coir mix as a peat substitute for potted chrysanthemum

    Energy Technology Data Exchange (ETDEWEB)

    Rosenani, A.B.; Lim, F.Y.; Thohirah, L.A.; Fauziah, C.I.

    2003-07-01

    Recent central processing of domestic wastewater in Malaysia has initiated investigations into the disposal/utilization of the sewage sludge produced. We had conducted an experiment to investigate the feasibility of using dewatered sewage sludge and coconut coir as a peat substitute in a potting medium for chrysanthemum. The experiment involved 9 treatments with sewage sludge (SS) and coconut coir (CC) mixed in different ratios (v/v) to replace peat in the standard potting medium of 3:2:1 (soil: peat: sand).The potting medium contained the following treatments, T1: peat + recommended rates of Agroblend (Ag), a slow release fertilizer, and Grofas (Gf), a foliar fertilizer (commonly used medium and fertilization), T2: [1SS:1CC] + Ag, T3: [1SS:1CC] + half recommended rates of Agroblend and Grofas (1/2Ag + 1/2Gf), T4: [2SS:1CC] + Ag, T5: [2SS:1CC] + 1/2Ag + 1/2Gf, T6: [3SS:1CC] + Ag, T7: [3SS:1CC] + 1/2Ag + 1/2Gf, T8: [4SS:1CC] + Ag, and T9: [4SS:1CC] + 1/2Ag + 1/2Gf; laid-out in a randomized complete block design with 5 replications. Results of the study show that in general the media with sludge and coconut coir mixtures produced better plant growth and higher total number of flowers than peat. However, the higher ratio of SS:CC, (4SS:1CC) produced poorer plant growth and less number of flowers. Increase in sewage sludge in the medium resulted in increase in foliar contents of heavy metals. This study demonstrates that sewage sludge and coconut coir mixture in the ratio of 1:1 may best substitute peat in the potting medium for chrysanthemum with only Agroblend fertilizer application. (author)

  7. Sewage sludge pretreatment and disposal. January 1980-February 1992 (Citations from the NTIS Data Base). Rept. for Jan 80-Feb 92

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    The bibliography contains citations concerning techniques and equipment used in the pretreatment processes and disposal of sewage sludges. Topics include resource and energy recovery operations, land disposal, composting, ocean disposal, and incineration. Digestion, dewatering, and disinfection are among the pretreatment processes discussed. Environmental aspects, including the effects on soils, plants, and animals, are also presented. (Contains 181 citations with title list and subject index.)

  8. Combustion of Sewage Sludge as Alternative Fuel for Cement Industry

    Institute of Scientific and Technical Information of China (English)

    LI Fuzhou; ZHANG Wei

    2011-01-01

    The combustion of sewage sludge and coal was studied by thermogravimetric analysis.Both differential scanning calorimetric analysis and derivative thermogravimetric profiles showed differences between combustion of sewage sludge and coal, and non-isothermal kinetics analysis method was applied to evaluate the combustion process. Based on Coats-Redfem integral method, some reaction models were tested,the mechanism and kinetics of the combustion reaction were discussed. The results show that the combustion of sewage sludge is mainly in the Iow temperature stage, meanwhile the ignition temperature and Arrhenius activation energy are lower than that of coal. The combustion of sewage sludge has the advantage over coal in some aspects, thus sewage sludge can partly replace coal used as cement industry fuel.

  9. The effect of bioleaching on sewage sludge pyrolysis.

    Science.gov (United States)

    Chen, Zhihua; Hu, Mian; Cui, Baihui; Liu, Shiming; Guo, Dabin; Xiao, Bo

    2016-02-01

    The effects of bioleaching on sewage sludge pyrolysis were studied. Sewage sludge was treated by bioleaching with solid concentrations of 6% (w/v), 8% (w/v), 10% (w/v). Results showed that bioleaching treatment could modify the physicochemical properties of sewage sludge and enhance the metals removal. The optimum removal efficiencies of heavy metals were achieved with solid concentration of 6% (w/v) bioleaching treatment: Cu, 73.08%; Zn, 78.67%; Pb, 24.65%; Cd, 79.46%. The characterization results of thermogravimetric analysis (TGA) showed that the bioleached sewage sludge with a 6% (w/v) solid concentration treatment was the easiest to decompose. Pyrolytic experiments of bioleached sewage sludge were performed in a laboratory-scale fixed bed reactor. Results indicated that bioleaching treatment greatly influenced the product yields and gas composition. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Sewage sludge treatment, utilisation and disposal; Schlammbehandlung, -verwertung und -beseitigung

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    In view of recent events and the resulting emotional and political decisions, the issue of sewage sludge treatment and disposal in Germany. must be seen in a new light. First, a new concept for sewage sludge management must be developed as recent legislation interferes with the 'classic' strategy of utilisation in agriculture, dumping and combustion. Scientists and sewage plant owners must find new ways to implement the specifications of the Act on Recycling and Waste Management. This ATV-DVWK training course discusses subjects that may be helpful on the new path. Starting from current legislation, problems, decision criteria and cost of sewage sludge treatment are gone into. Dimensioning fundamentals for sewage treatment plants re presented, and new and established treatment methods, operational problems and pollution problems are discussed. Further subjects are recycling of useful materials from sewage sludge, co-treatment of organic materials in fermenters, and disposal concepts for small and medium-sized communities. (orig.)

  11. Oil and coal from sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Naumann, H

    1981-01-01

    Under the leadership of professor Ernst Bayer a research group of Tuebingen succeeded in producing oil and coal from sewage sludge. The conversion of biomass into fossil fuels which in nature can only be calculated in historical periods of time is here brought about by the use of a catalyst on the basis of silicate and aluminium oxide, dopened with copper. First breakeven evaluations have given a real chance to be able to operate economically in a large scale plant the process being developed in laboratory tests.

  12. Use of sewage sludge for agriculture in Japan

    International Nuclear Information System (INIS)

    Kumazawa, K.

    1997-01-01

    In Japan, the use of sewage sludge and composted sewage sludge is gradually increasing. They are applied not only to agricultural land, but also to golf courses, parks, etc. The presence of heavy metals and pathogens poses a major problem for such utilization of sludge. Composting is a traditional method of sewage treatment. Laws have been introduced and guidelines prepared for proper and safe use of these materials by farmers. Public acceptance plays a crucial role. At a time when environmental preservation is a major issue in almost every aspect of life, greater emphasis will have to be placed on making sludge and compost hygienically acceptable with minimum contamination from pathogenic organisms and heavy metals. The advantages of using sludges as fertilizer for improving and sustaining soil fertility and crop production are many. This paper reviews studies conducted on the use of sewage sludge in agriculture in japan. (author)

  13. Synthesis, characterization, and secondary sludge dewatering performance of a novel combined silicon–aluminum–iron–starch flocculant

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Qintie, E-mail: qintlin@163.com; Peng, Huanlong; Zhong, Songxiong; Xiang, Jiangxin

    2015-03-21

    Highlights: • Silicon, aluminum, and iron were grafted onto starch chains to synthesize CSiAFS. • The sludge dewatering performance of CSiAFS was superior to PAC, PAM, and FeCl{sub 3}. • CSiAFS exhibited a good dewatering efficiency over a wide range of pH (3.0–11.0). • CSiAFS had a discontinuous surface with channels which helped to sludge dewatering. - Abstract: Flocculation is one of the most widely used cost-effective pretreatment method for sludge dewatering, and a novel environmentally friendly and efficient flocculant is highly desired in the sludge dewatering field. In this study, a novel combined silicon–aluminum–ferric–starch was synthesized by grafting silicon, aluminum, and iron onto a starch backbone. The synthesized starch flocculant was characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy, X-ray powder diffraction, and thermogravimetric analysis. The dewatering performance of secondary sludge was evaluated according to the capillary suction time, settling volume percentage, and specific resistance to filtration. The results indicated that the copolymer exhibited: (1) a good dewatering efficiency over a wide pH range of 3.0–11.0, (2) superior sludge dewatering performance compared to those of polyaluminum chloride (PACl), polyacrylamide (PAM), ferric chloride, and (3) a discontinuous surface with many channels or voids that helps to mobilize the impermeable thin layer of secondary sludge during filter pressing. Such a novel copolymer is a promising green flocculant for secondary sludge dewatering applications.

  14. Vitrification as an alternative to landfilling of tannery sewage sludge.

    Science.gov (United States)

    Celary, Piotr; Sobik-Szołtysek, Jolanta

    2014-12-01

    Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling. The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification. The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives. One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with flotation sewage sludge, and 45% v/v and 5% v/v, respectively, for precipitation sewage sludge. These combinations allowed for obtaining products with negligible heavy metal leaching levels and hardness similar to commercial glass, which suggests they could be potentially used as construction aggregate substitutes. Incineration of sewage sludge before the vitrification process lead to

  15. Monitoring and optimizing the co-composting of dewatered sludge: a mixture experimental design approach.

    Science.gov (United States)

    Komilis, Dimitrios; Evangelou, Alexandros; Voudrias, Evangelos

    2011-09-01

    The management of dewatered wastewater sludge is a major issue worldwide. Sludge disposal to landfills is not sustainable and thus alternative treatment techniques are being sought. The objective of this work was to determine optimal mixing ratios of dewatered sludge with other organic amendments in order to maximize the degradability of the mixtures during composting. This objective was achieved using mixture experimental design principles. An additional objective was to study the impact of the initial C/N ratio and moisture contents on the co-composting process of dewatered sludge. The composting process was monitored through measurements of O(2) uptake rates, CO(2) evolution, temperature profile and solids reduction. Eight (8) runs were performed in 100 L insulated air-tight bioreactors under a dynamic air flow regime. The initial mixtures were prepared using dewatered wastewater sludge, mixed paper wastes, food wastes, tree branches and sawdust at various initial C/N ratios and moisture contents. According to empirical modeling, mixtures of sludge and food waste mixtures at 1:1 ratio (ww, wet weight) maximize degradability. Structural amendments should be maintained below 30% to reach thermophilic temperatures. The initial C/N ratio and initial moisture content of the mixture were not found to influence the decomposition process. The bio C/bio N ratio started from around 10, for all runs, decreased during the middle of the process and increased to up to 20 at the end of the process. The solid carbon reduction of the mixtures without the branches ranged from 28% to 62%, whilst solid N reductions ranged from 30% to 63%. Respiratory quotients had a decreasing trend throughout the composting process. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Elemental transport and distribution in soils amended with incinerated sewage sludge.

    Science.gov (United States)

    Paramasivam, S; Sajwan, K S; Alva, A K; VanClief, D; Hostler, K H

    2003-05-01

    Sewage sludge (SS) is the major solid waste of sewage and wastewater treatment plants in cities around the world. Even though treated effluent water from wastewater treatment plants are utilized for irrigation, disposal of sewage sludge is becoming a serious problem. This is due to its high content of certain heavy metals still posing threat of accumulation in plants and groundwater contamination when it is used as soil amendment or disposed in landfills. Water treatment plants incinerate the dewatered activated sewage sludge (ISS) and dissolve the ash in water to store in ash ponds for long-term storage (WISS). A study was undertaken to evaluate the transport and leaching potential of various elements and their distribution within soil columns amended with various rates of ISS. Results of this study indicates that ISS from wastewater treatment plants can be used as soil amendment on agricultural lands at low to medium rates (< or = 100 Mg ha(-1)) without causing potential loading of metals into groundwater.

  17. Irradiation treatment of sewage sludge: History and prospects

    International Nuclear Information System (INIS)

    Bao Borong; Wu Minghong; Zhou Ruimin; Zhu Jinliang

    1998-01-01

    This paper first reviews the history of irradiation treatment of sewage sludge in the world. The first sludge irradiation plant was built in Geiselbullach, West Germany in 1973 and used 60 Co as irradiation source. Since then, many sludge irradiators were constructed in U.S.A., India, Japan, Canada, Poland, etc., which used 60 Co, 137 Cs or electron beam as irradiation sources. The paper then describes some basic research on irradiation treatment of sewage sludge including optimization of irradiation parameters, synergistic effect of radiation with heat, oxygenation, irradiation-composting and potential applications of treated sludge. Some proposals have been suggested for further development of this technology in the future

  18. Sludge, garbage may fuel California sewage plant

    Energy Technology Data Exchange (ETDEWEB)

    Sieger, R B

    1977-01-01

    The combustion and pyrolysis of sewage sludge and refuse-derived fuel (RFD) in multiple-hearth furnaces were recommended as a means of generating energy to power the Central Contra Costa Sanitary District's 30 mgd wastewater treatment plant using an off-gas from the pyrolysis process. In a full-scale test, a furnace in Concord, once used for sewage sludge incineration, was operated under O/sub 2/-starved conditions by limiting air addition through the burners and air nozzles, resulting in partial combustion. Using temperature as the controlled variable, the process was regulated to form a fuel gas through composition of the organic feed matter. Just enough fuel gas was combusted to evaporate moisture in the feed solids and furnish heat for the decomposition process. During most of the testing the afterburner was maintained at a temperature > 1400/sup 0/F with pyrolysis gas. At this temperature, automatic ignition of the gas occurred. When the gas generated dropped to a low heat of combustion because of high feed moisture content, the afterburner burner was used to ignite the gas. Some test observations are discussed. Preparation of the solid waste for processing by the use of shredders, air classifiers, and magnetic separators is described.

  19. Thermophilic versus Mesophilic Anaerobic Digestion of Sewage Sludge: A Comparative Review

    Science.gov (United States)

    Gebreeyessus, Getachew D.; Jenicek, Pavel

    2016-01-01

    During advanced biological wastewater treatment, a huge amount of sludge is produced as a by-product of the treatment process. Hence, reuse and recovery of resources and energy from the sludge is a big technological challenge. The processing of sludge produced by Wastewater Treatment Plants (WWTPs) is massive, which takes up a big part of the overall operational costs. In this regard, anaerobic digestion (AD) of sewage sludge continues to be an attractive option to produce biogas that could contribute to the wastewater management cost reduction and foster the sustainability of those WWTPs. At the same time, AD reduces sludge amounts and that again contributes to the reduction of the sludge disposal costs. However, sludge volume minimization remains, a challenge thus improvement of dewatering efficiency is an inevitable part of WWTP operation. As a result, AD parameters could have significant impact on sludge properties. One of the most important operational parameters influencing the AD process is temperature. Consequently, the thermophilic and the mesophilic modes of sludge AD are compared for their pros and cons by many researchers. However, most comparisons are more focused on biogas yield, process speed and stability. Regarding the biogas yield, thermophilic sludge AD is preferred over the mesophilic one because of its faster biochemical reaction rate. Equally important but not studied sufficiently until now was the influence of temperature on the digestate quality, which is expressed mainly by the sludge dewateringability, and the reject water quality (chemical oxygen demand, ammonia nitrogen, and pH). In the field of comparison of thermophilic and mesophilic digestion process, few and often inconclusive research, unfortunately, has been published so far. Hence, recommendations for optimized technologies have not yet been done. The review presented provides a comparison of existing sludge AD technologies and the gaps that need to be filled so as to optimize

  20. Biological sulphate reduction with primary sewage sludge in an ...

    African Journals Online (AJOL)

    The success of the UASB reactor depends largely on the settling properties and stability of the sludge bed which comprises the anaerobic active biomass. The solid-liquid separation behaviour of the sludge bed in 2 UASB reactors (R1 at 35oC and R2 at 20oC) fed with primary sewage sludge and sulphate was investigated ...

  1. Environmentally compatible sewage sludge disposal; Umweltgerechte Klaerschlammentsorgung

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J. [Technische Univ. Braunschweig (Germany). Inst. fuer Mechanische Verfahrenstechnik; Schwedes, J. [Technische Univ. Braunschweig (Germany). Inst. fuer Mechanische Verfahrenstechnik

    1997-09-01

    Cleaning of municipal and industrial waste water is done by means of biological processes: micro-organisms degrade pollutants. The resulting products are, besides cleaned waste water, sewage sludge and surplus sludge. Their disposal involves ecological and economic problems. One approach to their partial disposal is their degradation in a digester. Approximately one half of the organic substance is converted by anaerobic bacteria into energy-rich biogas. Optimization of this digestion process accelerates the anaerobic degradation process, increases the accruing amount of digester gas and reduces the volume of digested sludge to be disposed of. With these objectives, the Institute fuer Mechanische Verfahrenstechnik is conducting research into the mechanical treatment of micro-organisms remaining in surplus sludge by means of different treatment devices. The project is sponsored under the programme of the Deutsche Forschungsgemeinschaft DFG ``Biological processes with dispersive solids``. Mechanical treatment renders the cell constituents exploitable to anaerobic bacteria; the resulting sludge degradation is more rapid and more complete. (orig./ABI) [Deutsch] Zur Reinigung haeuslicher und industrieller Abwaesser werden biologische Prozesse eingesetzt. Dabei sorgen Mikroorganismen fuer den Abbau der Verunreinigungen. Neben dem gereinigten Abwasser fallen Primaer- und Ueberschussschlamm an, deren Entsorgung oekologische und oekonomische Probleme verursacht. Ein Weg zur partiellen Beseitigung dieser Klaerschlaemme ist ihr Abbau in einem Faulbehaelter. Dabei wird etwa die Haelfe der organischen Substanz durch anaerobe Bakterien zu einem energiereichen Biogas umgewandelt. Eine Optimierung dieses Faulprozesses beinhaltet: 1. Beschleunigung des anaeroben Abbauprozesses, 2. Erhoehung der anfallenden Faulgasmenge und 3. Reduzierung der zu entsorgenden Faulschlammenge. Mit diesen Zielsetzungen wird am Institut fuer Mechanische Verfahrenstechnik im Rahmen der DFG

  2. Sludge dewatering on filters aiming the utilization as fuel; Desaguamento de lodos em filtro visando aproveitamento como combustivel

    Energy Technology Data Exchange (ETDEWEB)

    Paschoalim, Luis Gustavo; Neves, Jose Mangolini

    1993-12-31

    This work presents modern methodologies for sludge dewatering and alternatives for environmental disposal of the so obtained cakes. Among the possible alternatives, special emphasis is given to the characterization and study of the variables which determine the behaviour of dewatering operation of sludges form pulp and paper industries. Results are presents for bench scale tests and pilot plant tests 28 refs., 9 figs., 7 tabs.

  3. Sludge dewatering on filters aiming the utilization as fuel; Desaguamento de lodos em filtro visando aproveitamento como combustivel

    Energy Technology Data Exchange (ETDEWEB)

    Paschoalim, Luis Gustavo; Neves, Jose Mangolini

    1992-12-31

    This work presents modern methodologies for sludge dewatering and alternatives for environmental disposal of the so obtained cakes. Among the possible alternatives, special emphasis is given to the characterization and study of the variables which determine the behaviour of dewatering operation of sludges form pulp and paper industries. Results are presents for bench scale tests and pilot plant tests 28 refs., 9 figs., 7 tabs.

  4. Enhanced composting of radiation disinfected sewage sludge

    International Nuclear Information System (INIS)

    Kawakami, W.; Hashimoto, S.

    1984-01-01

    Studies on isothermal composting of radiation disinfected sewage sludge and liquid chromatography of water extracts of the products were carried out. The optimum temperature and pH were around 50 deg C and 7 to 8, respectively. The repeated use of products as seeds increased the rate of CO 2 evolution. The rate reached a maximum within 10 hours and decreased rapidly, and the CO 2 evolution ceased after about 3 days. The conversion of organic carbon to carbon dioxide attained to about 40% for the repeated use of products as seeds at the optimum conditions. As long as seeds as available were used, no remarkable difference was found in the composting of unirradiated and irradiated sludges. The composting process using radiation, however, can be carried out at the optimum conditions and is expected to shorten the composting period, because it is not necessary to keep fermentation temperature higher to reduce pathogen in sludge. Liquid chromatographic studies of the products showed that low molecular components decreased and higher molecular ones increased with fermentation. An index expressing the degree of reduction of easily decomposable organics was presented. The index also showed that the optimum temperature for fermentation was 50 deg C. (author)

  5. On the rheological characteristics of sewage sludge

    Directory of Open Access Journals (Sweden)

    Tomáš Vítěz

    2010-01-01

    Full Text Available The work is focused on characterization of rheological behavior of sewage sludges sampled at different stages of waste water treatment. The main attention was focused on dynamic viscosity dependence on temperature, and shear rate. The sludge samples were examined under temperature ranging from 1 °C to 25 °C and under shear rate ranging from 0.34 s−1 to 68 s−1. Rotary digital viscometer (concentric cylinders geometry was used to perform the reological measurements. The solids content of the sludge samples ranged from 0.43 % to 21.45 % (A and C samples, respectively and ash free dry mass from 56.21 % to 67.80 % (A and B samples, respectively. The tested materials were found to be of non–Newtoninan nature and temperature dependent. Measured data were successfully cha­ra­cte­ri­zed by several mathematical models (Arrhenius, Bingham Plastic, Casson Law, Exponential, Gaussian, and IPC Paste in MATLAB® software with satisfying correlations between experimental and computed results. The best match (R2 = 0.999 was received with use of Gaussian model, in both cases, shear rate and temperature dependence. The results are quite useful e.g. for the purpose of technological equipment design.

  6. Chitosan use in chemical conditioning for dewatering municipal-activated sludge.

    Science.gov (United States)

    Zemmouri, H; Mameri, N; Lounici, H

    2015-01-01

    This work aims to evaluate the potential use of chitosan as an eco-friendly flocculant in chemical conditioning of municipal-activated sludge. Chitosan effectiveness was compared with synthetic cationic polyelectrolyte Sedipur CF802 (Sed CF802) and ferric chloride (FeCl₃). In this context, raw sludge samples from Beni-Messous wastewater treatment plant (WWTP) were tested. The classic jar test method was used to condition sludge samples. Capillary suction time (CST), specific resistance to filtration (SRF), cakes dry solid content and filtrate turbidity were analyzed to determine filterability, dewatering capacity of conditioned sludge and the optimum dose of each conditioner. Data exhibit that chitosan, FeCl₃and Sed CF802 improve sludge dewatering. Optimum dosages of chitosan, Sed CF802 and FeCl₃allowing CST values of 6, 5 and 9 s, were found, respectively, between 2-3, 1.5-3 and 6 kg/t ds. Both polymers have shown faster water removal with more permeable sludge. SRF values were 0.634 × 10¹², 0.932 × 10¹² and 2 × 10¹² m/kg for Sed CF802, chitosan and FeCl₃respectively. A reduction of 94.68 and 87.85% of the filtrate turbidity was obtained with optimal dosage of chitosan and Sed CF802, respectively. In contrast, 54.18% of turbidity abatement has been obtained using optimal dosage of FeCl₃.

  7. Recent developments in Sandia Laboratories' sewage sludge irradiation program

    International Nuclear Information System (INIS)

    Sivinski, H.D.; Brandon, J.R.; Morris, M.E.; Neuhauser, K.S.; Ward, R.L.; McCaslin, B.; Smith, G.S.

    1977-01-01

    Pathogen reduction studies show that gamma irradiation is effective in inactivating pathogenic bacteria, parasite ova, and viruses in liquid sludges. Ammonia is shown to be virucidal to poliovirus and several other enteric viruses. Sludge processing costs are relatively economical for composted or dried sludges, but only marginally competitive with costs of heat treatment for liquid sludges. Physical and chemical studies show that effects of irradiation of sludges on dewatering properties are insignificant when compared to the effects of polymer addition. Dried, irradiated undigested sludge has significant nutritional value as a feed supplement for sheep and cattle and in agronomic uses such as greenhouses and field plots. No significant harmful effects have been demonstrated in the feeding program. Product enhancement studies are under way, including schemes for removing nitrogen from wastewaters and adding it to sludges in the form of ammonium salts

  8. Dewatering and low-temperature pyrolysis of oily sludge in the presence of various agricultural biomasses.

    Science.gov (United States)

    Zhao, Song; Zhou, Xiehong; Wang, Chuanyi; Jia, Hanzhong

    2017-08-24

    Pyrolysis is potentially an effective treatment of waste oil residues for recovery of petroleum hydrocarbons, and the addition of biomass is expected to improve its dewatering and pyrolysis behavior. In this study, the dewatering and low-temperature co-pyrolysis of oil-containing sludge in the presence of various agricultural biomasses, such as rice husk, walnut shell, sawdust, and apricot shell, were explored. As a result, the water content gradually decreases with the increase of biomass addition within 0-1.0 wt % in original oily sludge. Comparatively, the dewatering efficiency of sludge in the presence of four types of biomasses follows the order of apricot shell > walnut shell > rice husk > sawdust. On the other hand, rice husk and sawdust are relatively more efficient in the recovery of petroleum hydrocarbons compared with walnut shell and apricot shell. The recovery efficiency generally increased with the increase in the biomass content in the range of 0-0.2 wt %, then exhibited a gradually decreasing trend with the increase in the biomass content from 0.2 to 1.0 wt %. The results suggest that optimum amount of biomass plays an important role in the recovery efficiency. In addition, the addition of biomass (such as rice husk) also promotes the formation of C x H y and CO, increasing the calorific value of pyrolysis residue, and controlled the pollution components of the exhaust gas discharged from residue incineration. The present work implies that biomass as addictive holds great potential in the industrial dewatering and pyrolysis of oil-containing sludge.

  9. Radiation disinfection of sewage sludge and composting of the irradiated sludge

    International Nuclear Information System (INIS)

    Hashimoto, Shoji; Nishimura, Koichi; Watanabe, Hiromasa; Kawakami, Waichiro

    1985-01-01

    In the radiation disinfected sewage sludge, its stabilization is necessary with the composting. In this disinfected sludge, there is no need of keeping it at high temperature at the cost of fermentation velocity. The fermentation velocity can thus be set to obtain its maximum value. In sewage sludge utilization of farm land, to prevent the contamination with pathogenic bacteria and the secondary pollution, the radiation disinfection of dehydrated sludge and the composting of the disinfected sludge have been studied. The disinfection effect when an electron accelerator is used for the radiation source is described. Then, the composting of the disinfected sludge is described in chemical kinetics of the microorganisms. (Mori, K.)

  10. Addition of biochar to sewage sludge decreases freely dissolved PAHs content and toxicity of sewage sludge-amended soil.

    Science.gov (United States)

    Stefaniuk, Magdalena; Oleszczuk, Patryk

    2016-11-01

    Due to an increased content of polycyclic aromatic hydrocarbons (PAHs) frequently found in sewage sludges, it is necessary to find solutions that will reduce the environmental hazard associated with their presence. The aim of this study was to determine changes of total and freely dissolved concentration of PAHs in sewage sludge-biochar-amended soil. Two different sewage sludges and biochars with varying properties were tested. Biochars (BC) were produced from biogas residues at 400 °C or 600 °C and from willow at 600 °C. The freely dissolved PAH concentration was determined by means of passive sampling using polyoxymethylene (POM). Total and freely dissolved PAH concentration was monitored at the beginning of the experiment and after 90 days of aging of the sewage sludge with the biochar and soil. Apart from chemical evaluation, the effect of biochar addition on the toxicity of the tested materials on bacteria - Vibrio fischeri (Microtox ® ), plants - Lepidium sativum (Phytotestkit F, Phytotoxkit F), and Collembola - Folsomia candida (Collembolan test) was evaluated. The addition of biochar to the sewage sludges decreased the content of C free PAHs. A reduction from 11 to 43% of sewage sludge toxicity or positive effects on plants expressed by root growth stimulation from 6 to 25% to the control was also found. The range of reduction of C free PAHs and toxicity was dependent on the type of biochar. After 90 days of incubation of the biochars with the sewage sludge in the soil, C free PAHs and toxicity were found to further decrease compared to the soil with sewage sludge alone. The obtained results show that the addition of biochar to sewage sludges may significantly reduce the risk associated with their environmental use both in terms of PAH content and toxicity of the materials tested. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. The presence of contaminations in sewage sludge - The current situation.

    Science.gov (United States)

    Fijalkowski, Krzysztof; Rorat, Agnieszka; Grobelak, Anna; Kacprzak, Malgorzata J

    2017-12-01

    Sewage sludge/biosolids are by-wastes of municipal and industrial wastewater treatment. As sources of nutrients (C, N, P) they are widely used in intensive farming where large supplementation of organic matter to maintain fertility and enhance crop yields is needed. However, according to the report of European Commission published in 2010, only 39% of produced sewage sludge is recycled into agriculture in the European Union. This situation occurs mainly due to the fact, that the sewage sludge may contain a dangerous volume of different contaminants. For over decades, a great deal of attention has been focused on total concentration of few heavy metals and pathogenic bacteria Salmonella and Escherichia coli. The Sewage Sludge Directive (86/278/EEC) regulates the allowable limits of Zn, Cu, Ni, Pb, Cd, Cr and Hg and pathogens and allows for recovery of sludge on land under defined sanitary and environmentally sound conditions. In this paper, a review on quality of sewage sludge based on the publications after 2010 has been presented. Nowadays there are several papers focusing on new serious threats to human health and ecosystem occurring in sewage sludge - both chemicals (such as toxic trace elements - Se, Ag, Ti; nanoparticles; polyaromatic hydrocarbons; polychlorinated biphenyl; perfluorinated surfactants, polycyclic musks, siloxanes, pesticides, phenols, sweeteners, personal care products, pharmaceuticals, benzotriazoles) and biological traits (Legionella, Yersinia, Escherichia coli O157:H7). Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Future of sewage sludge in disposal; Klaerschlammentsorgung. Quo vadis?

    Energy Technology Data Exchange (ETDEWEB)

    Wiechmann, Benjamin [Umweltbundesamt, Dessau (Germany). Fachgebiet III 2.4 - Abfalltechnik, Abfalltechniktransfer

    2013-06-01

    The thermal treatment of sewage sludge is changing continuously. In the future, the disposal of sewage sludge is framed and will be adjust by the idea of resource saving. Simultaneously due the amendment of the 17th BImSchV emission control will be encouraged. Although, more than a quarter of the upcoming sludge is incinerated in mono-incineration plants, this amount should be increased. Therefore, it is necessary to build up new capacities of mono-incineration plants. The legal and strategic framework which has an influence on the combustion of sludge will be examined in this paper. (orig.)

  13. Effect of TiO2 nanoparticles on UASB biomass activity and dewatered sludge.

    Science.gov (United States)

    Yadav, Tushar; Mungray, Alka A; Mungray, Arvind K

    2017-02-01

    The accumulation of the nanowastes in the wastewater treatment plants has raised several concerns; therefore, it is an utmost priority to study the nanoparticle (NP) toxicity in such systems. In this work, the effect of TiO 2 NPs on up-flow anaerobic sludge blanket (UASB) microflora and their photocatalytic effect on dewatered sludge were studied. We observed 99.98% removal of TiO 2 NPs by sludge biomass within 24 h, though negligible toxicity was found up to 100 mg/L TiO 2 concentration on extracellular polymeric substances (EPS), volatile fatty acid and biogas generation. The low toxicity corresponds to the agglomeration of TiO 2 NPs in UASB sludge. Alterations in dewatered sludge biochemical composition and increase in cell damage were observed upon exposure to sunlight as evidenced by FTIR and fluorescent microscopy, respectively. Results suggest the negligible toxicity of TiO 2 NPs on UASB biomass activity; however, once exposed to open environment and sunlight, they may exert detrimental effects.

  14. Fermentation of sewage sludge using the MixAlco process

    African Journals Online (AJOL)

    Nafiisah

    Sewage sludge consists mainly of the excess biomass produced during biological treatment ... The traditional method of converting biomass to alcohol is by simultaneous saccharification .... Lime pretreatment and enzymatic hydrolysis of corn ...

  15. Vitrification as an alternative to landfilling of tannery sewage sludge

    International Nuclear Information System (INIS)

    Celary, Piotr; Sobik-Szołtysek, Jolanta

    2014-01-01

    Highlights: • The possibility of vitrification of tannery sewage sludge was investigated. • Glass cullet was substituted with different wastes of mineral character. • Component ratio in the processed mixtures was optimized. • Environmental safety of the acquired vitrificates was verified. • An alternative management approach of usually landfilled waste was presented. - Abstract: Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling. The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification. The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives. One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with

  16. Vitrification as an alternative to landfilling of tannery sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Celary, Piotr, E-mail: pcelary@is.pcz.czest.pl; Sobik-Szołtysek, Jolanta, E-mail: jszoltysek@is.pcz.czest.pl

    2014-12-15

    Highlights: • The possibility of vitrification of tannery sewage sludge was investigated. • Glass cullet was substituted with different wastes of mineral character. • Component ratio in the processed mixtures was optimized. • Environmental safety of the acquired vitrificates was verified. • An alternative management approach of usually landfilled waste was presented. - Abstract: Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling. The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification. The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives. One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with

  17. 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.

  18. Electrodialytic recovery of phosphorus from chemically precipitated sewage sludge ashes

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    Phosphorus scarcity requires improved recover and reuse of urban sources; the recycling of this nutrient from sewage sludge has become increasingly important in the last years. Using an innovative electrodialytic process, the present study shows the potential for P separation from Fe and Al...... precipitated sewage sludge ash using this technique, with a recovery rate of around 70%. Furthermore, heavy metals were removed from the phosphorous fraction, producing a pure and safe phosphorus source in the end....

  19. Electrodialytic recovery of phosphorus from chemically precipitated sewage sludge ashes

    DEFF Research Database (Denmark)

    Viader, Raimon Parés; Erland Jensen, Pernille; Ottosen, Lisbeth M.

    Phosphorus scarcity requires improved recover and reuse of urban sources; the recycling of this nutrient from sewage sludge has become increasingly important in the last years. Using an innovative electrodialytic process, the present study shows the potential for P separation from Fe and Al...... precipitated sewage sludge ash using this technique, with a recovery rate of around 70%. Furthermore, heavy metals were removed from the phosphorous fraction, producing a pure and safe phosphorus source in the end...

  20. Odor assessment for sewage sludge samples 300A01002

    International Nuclear Information System (INIS)

    Cash, D.B.; Molton, P.M.

    1976-12-01

    The use of radiation as a means of detoxifying sewage sludge as an alternate to the more conventional biological digestion treatment method was studied. A combination of gamma irradiation and heat (thermoradiation) treatment is being considered. In support of this effort, Battelle's Pacific Northwest Laboratories (PNL) were requested to assess the odor change of the sewage sludge, if any, that occurs with time after the samples were subjected to the treatment conditions. The test methods and results are presented

  1. Properties of bacterial radioresistance observed in sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, H; Ito, H; Takehisa, M [Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment; Iizuka, H

    1981-09-01

    The changes in radiosensitivities of bacteria in sludge were investigated. The coliforms are more radioresistant in raw sludge than in cake (dewatered sludge). This radioresistance of coliforms was observed not only in raw sludge but also in the cake diluted with water. The radioresistance was independent of the difference of treatment plant, kind of sludge, and season. The oxygen effect on the radioresistance was not observed, but the resistance was changed during storage of sludge. Escherichia coli isolated from sludge was radiosensitive in buffer, but its radiosensitivity was protected by the water-extracts of sludge. On the other hand, radioresistant bacteria were present in total bacteria of sludge irradiated at 2 Mrad. However, the dominant flora in the irradiated sludge consisted of radiosensitive bacteria (mainly Pseudomonas). When a strain of radiosensitive Pseudomonas was irradiated in raw sludge and diluted cake, the radiosensitivity was remarkably protected. From these results, it is suggested that a factor affecting the radiosensitivity of bacteria is present in sludge.

  2. Properties of bacterial radioresistance observed in sewage sludge

    International Nuclear Information System (INIS)

    Watanabe, Hiroshi; Ito, Hitoshi; Takehisa, Masaaki; Iizuka, Hiroshi.

    1981-01-01

    The changes in radiosensitivities of bacteria in sludge were investigated. The coliforms are more radioresistant in raw sludge than in cake (dewatered sludge). This radioresistance of coliforms was observed not only in raw sludge but also in the cake diluted with water. The radioresistance was independent of the difference of treatment plant, kind of sludge, and season. The oxygen effect on the radioresistance was not observed, but the resistance was changed during storage of sludge. Escherichia coli isolated from sludge was radiosensitive in buffer, but its radiosensitivity was protected by the water-extracts of sludge. On the other hand, radioresistant bacteria were present in total bacteria of sludge irradiated at 2 Mrad. However, the dominant flora in the irradiated sludge consisted of radiosensitive bacteria (mainly Pseudomonas). When a strain of radiosensitive Pseudomonas was irradiated in raw sludge and diluted cake, the radiosensitivity was remarkably protected. From these results, it is suggested that a factor affecting the radiosensitivity of bacteria is present in sludge. (author)

  3. Preparing sewage sludge for land application or surface disposal: A guide for preparers of sewage sludge on the monitoring, record keeping, and reporting requirements of the federal standards for the use of disposal of sewage sludge, 40 CFR part 503

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    The document focuses on the monitoring, recordkeeping, and reporting requirements that apply to persons who prepare sewage sludge or a material derived from sewage sludge. It defines persons who prepare sewage sludge and then summarizes their general responsibilities. USEPA promulgated at 40 CFR Part 503 Phase 1 of the risk-based regulations that govern the final use or disposal of sewage sludge. The intent of the Federal program is to ensure that the use or disposal of sewage sludge occurs in a way that protects both human health and the environment. The Part 503 regulation establishes general requirements, pollutant limits, operational standards, and management practices, as well as monitoring, recordkeeping, and reporting requirements. These requirements apply to sewage sludge that is land applied, placed on a surface disposal site, or incinerated in a sewage sludge-only incinerator.

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

    Science.gov (United States)

    Borowski, Sebastian; Kubacki, Przemysław

    2015-06-01

    Slaughterhouse wastes (SHW) are potentially very attractive substrates for biogas production. However, mono-digestion of these wastes creates great technological problems associated with the inhibitory effects of ammonia and fatty acids on methanogens as well as with the foaming in the digesters. In the following study, the co-digestion of slaughterhouse wastes with sewage sludge (SS) was undertaken. Batch and semi-continuous experiments were performed at 35°C with municipal sewage sludge and pig SHW composed of meat tissue, intestines, bristles and post-flotation sludge. In batch assays, meat tissue and intestinal wastes gave the highest methane productions of 976 and 826 dm(3)/kg VS, respectively, whereas the methane yield from the sludge was only 370 dm(3)/kg VS. The co-digestion of sewage sludge with 50% SHW (weight basis) provided the methane yield exceeding 600 dm(3)/kg VS, which was more than twice as high as the methane production from sewage sludge alone. However, when the loading rate exceeded 4 kg VS/m(3) d, a slight inhibition of methanogenesis was observed, without affecting the digester stability. The experiments showed that the co-digestion of sewage sludge with large amount of slaughterhouse wastes is feasible, and the enhanced methane production does not affect the digester stability. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Considerations in the public acceptance of sewage sludge irradiation systems

    International Nuclear Information System (INIS)

    Dix, G.P.

    1975-01-01

    Considerations associated with public acceptance of municipal sewage sludge irradiation systems are discussed including the benefit to society, public information and safeguards. Public acceptance of products is based upon the benefit to society as measured by reduced consumer costs, minimization of public risk and enhancement of the quality of life and the environment. When viewed in this positive light, the sludge irradiator has high potential benefits to the community. If large-scale engineering experiments show that sludge irradiation is more cost-effective than other methods, reduced consumer costs would result. Today many sewage plants do not consistently remove pathogens from sludge; sludge irradiation could be an effective method of pathogen removal and result in avoidance of a major public risk. The sludge irradiator may be able to clean up recreational areas, reduce noxious odours from sewage treatment facilities, and reduce the energy requirements for producing fertilizer and soil conditioners and conserve their mineral content. Plant safeguards must be explained to dispel public concern that the contents of the source can be released to the sludge accidentally. This will be the main issue within the technical sector of the public, and the design, procedural and administrative safeguards of the plant must be fully explained. The primary risk associated with sludge irradiators will be the remote possibility of source leakage into the sludge. The various safeguards in sludge irradiation plants are discussed in detail including the form of the radionuclide, encapsulation, the irradiation chamber, safeguards instrumentation, shielding and thermal safeguards. (Author)

  6. 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 ...

  7. Co-composting of sewage sludge and Echinochloa pyramidalis (Lam.)

    African Journals Online (AJOL)

    Yaoundé-Cameroon) in order to assess the effect of three sewage sludge: Macrophyte ratios on the co-composting process and compost quality. The ratios were T1: 25 kg of plant material (Echinochloa pyramidalis) and 75 kg sludge; T2: 50 kg ...

  8. Phosphate Recovery From Sewage Sludge Containing Iron Phosphate

    NARCIS (Netherlands)

    Wilfert, P.K.

    2018-01-01

    The scope of this thesis was to lay the basis for a phosphate recovery technology that can be applied on sewage sludge containing iron phosphate. Such a technology should come with minimal changes to the existing sludge treatment configuration while keeping the use of chemicals or energy as small as

  9. Recycling of Treated Sewage Sludge in Sustainable Agriculture

    International Nuclear Information System (INIS)

    Galal, Y.G.M.

    2012-01-01

    Agricultural utilization of organic wastes amendments has been shown to be a sound alternative for both waste recycling and soil fertility improvement. Also, attention had been paid to use the biological agents that most cheap and safe for agricultural application in poor sandy soils. In this respect, irradiated sewage sludge and individual and dual inoculants of Azospirillum, Rhizobium and Arbuscular mycorrhizae fungi were applied for reclamation and development of low fertile sandy soil. The fertilizer value of sewage sludge has been known for a long time, but the concomitant problems of heavy metals in soil, as a result of its continuous applications, have only been recognized recently. Most of the studies were devoted to follow up the effect of high concentrations of metals when sewage sludge was applied, but no attention has been accelerated about its effect on soil microorganisms. Adverse effects of sewage sludge on microbial activity and populations of cyanobacteria, Rhizobium, Mycorrhizae and total microbial biomass have been detected in some cases of Europe. For example, N 2 fixation by free-living heterotrophic bacteria was found to be inhibited at concentrations (mg kg -1 ) of 127 Zn, 37 Cu, 21 Ni, 3.4 Cd, 52 Cr, and 71 Pb. Impact of bio fertilizers combined with irradiated sewage sludge on micro nutrients, e.g. Fe, Zn, Mn, Pb availability to clover and wheat plants, and productivity of both crops was the main objective of this study. In this connection, nuclear technology may offer a safety method against pathogenic effects of sewage sludge applied into agricultural ecosystems. Therefore, irradiated sludge is considered as safely source of organic wastes as well as the benefits on enrichment the low fertile soil with available nutrients, which act as a limiting factor for crop production. The N, P and K nutrients uptake by either shoots or grains of tested crops were positively and significantly affected by application of sewage sludge as well as bio

  10. INVESTIGATION OF BIOFLOCCULANT AS RENEWABLE DEWATERING AID IN SLUDGE TREATMENT

    Directory of Open Access Journals (Sweden)

    MOHAMMED SAEDI JAMI

    2018-06-01

    Full Text Available Sludge treatment is one of the most important and expensive steps in water and wastewater treatment plants. Chemical conditioners such as polyaluminum chloride, aluminum sulfate, Fenton’s reagent, gypsum, and polyacrylamide can produce byproducts that cause health and environmental problems. Moringa oleifera (MO seeds can be used as a natural alternative to chemical conditioners. The bioactive materials have to be extracted from MO seeds for better performance. In this study, the treatment methods of MO seeds were the bioactive extraction by NaCl (1 M and oil extraction by hexane solvent, as well as the untreated (crude seeds powder. Synthetic sludge samples were prepared using kaolin suspension (5% w/v. The most effective coagulant-form was determined based on the values of settling velocity (Vs and sludge volume index (SVI. Results showed that extraction by NaCl gave the best results of 0.41 cm/min of settling velocity and 63.39 ml/g of SVI. A SVI value greater than 150 ml/g indicates poor settling qualities whereas the control sludge of the current study was 100 ml/g. The most effective coagulant-form was optimized with respect to three process conditions: MO seeds dosage, mixing speed, and contact time. The experiments were designed using 2 Level Factorial-Design by Design-Expert software. The optimum process conditions were seeds dosage of 3246 mg/l, mixing speed of 102 rpm, and mixing time of 29 min. MO seeds can be considered as a natural coagulant that can be used as main sludge conditioner. ABSTRAK: Rawatan kotoran mendapan adalah salah satu rawatan penting dan termahal dalam merawat air dan sisa­ kumbahan loji. Perapi kimia seperti poli-aluminium klorida, aluminium sulfida, reagen Fenton, gipsum, dan poli-akrilamida menghasilkan sisa, di mana memberi kesan kepada kesihatan dan alam sekitar. Benih Moringa oleifera (MO boleh digunakan sebagai bahan ganti semula jadi kepada perapi kimia. Bahan bio-aktif perlu diekstrak daripada benih

  11. Hydraulic conductivity and soil-sewage sludge interactions

    Directory of Open Access Journals (Sweden)

    Silvio Romero de Melo Ferreira

    2011-10-01

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

  12. Response of rice to nitrogenous fertilizer and irradiated sewage sludge

    International Nuclear Information System (INIS)

    Azam, F.; Lodhi, A.; Sajjad, M.H.

    2003-01-01

    A greenhouse pot experiment was conducted to study the effect of Gamma-irradiated sewage sludge, applied alone or along with /sup 15/N-labelled ammonium sulphate (1.0 atom % /sup 15/N excess), on rice yield and N uptake. Six-kg portions of a clay loam were amended wit sewage sludge to obtain N addition rates of 30, 60, 90 and 120 mg kg/sub -1/ soil. In other treatments nitrogen was applied at 120 mg kg/sup -1/ as /sup 15/N-labelled ammonium sulphate or 120 mg kg/sub -1/ as /sup 15/NH/sub 4/-N + sludge-N in the ratios of 1:3, 1:1, or 3:1. All the treatments were given before transplanting rice. Three healthy seedlings (4-week old) of rice (Oryza sativa L., var. Bas-Pak) were transplanted pot/sup -1/ and the plants harvested at maturity. Application of sewage sludge caused a significant improvement in rice yield. Grain yield increased by 188% at sludge-N of 120 mg N kg/sup -1/. The yield benefit at similar rate of fertilizer N was 304%, the increase being more at higher rates of application. The increase in rice yield was dependent on uptake of N and sewage sludge significantly improved the availability of N to the plants. The additional plant N in sludge treated soil was partially attributable to enhanced mineralization of soil N and N/sub 2/ fixation by free living microorganisms. Application of inorganic N led to a significant increase in the availability of N to plants from soil organic matter and sewage sludge. Results of combined application suggested that substantial savings of fertilizer N can be made by using sewage sludge on rice-fields. (author)

  13. Biological sulphate reduction with primary sewage sludge in an ...

    African Journals Online (AJOL)

    2009-07-31

    Jul 31, 2009 ... The success of the UASB reactor depends largely on the settling properties and stability of the sludge bed which comprises the anaerobic active biomass. The solid-liquid separation behaviour of the sludge bed in 2 UASB reactors (R1 at 35oC and. R2 at 20oC) fed with primary sewage sludge and sulphate ...

  14. Bioelectrochemically-assisted anaerobic composting process enhancing compost maturity of dewatered sludge with synchronous electricity generation.

    Science.gov (United States)

    Yu, Hang; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Yunshu; Zheng, Zhen; Hao, Xiaodi

    2015-10-01

    Bioelectrochemically-assisted anaerobic composting process (AnCBE) with dewatered sludge as the anode fuel was constructed to accelerate composting of dewatered sludge, which could increase the quality of the compost and harvest electric energy in comparison with the traditional anaerobic composting (AnC). Results revealed that the AnCBE yielded a voltage of 0.60 ± 0.02 V, and total COD (TCOD) removal reached 19.8 ± 0.2% at the end of 35 d. The maximum power density was 5.6 W/m(3). At the end of composting, organic matter content (OM) reduction rate increased to 19.5 ± 0.2% in AnCBE and to 12.9 ± 0.1% in AnC. The fuzzy comprehensive assessment (FCA) result indicated that the membership degree of class I of AnCBE compost (0.64) was higher than that of AnC compost (0.44). It was demonstrated that electrogenesis in the AnCBE could improve the sludge stabilization degree, accelerate anaerobic composting process and enhance composting maturity with bioelectricity generation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Present situation and objective of sewage sludge treatment and disposal; Ausgangssituation und Zielstellung der Klaerschlammbehandlung und -entsorgung

    Energy Technology Data Exchange (ETDEWEB)

    Wittchen, F. [BC Berlin-Consult GmbH, Berlin (Germany); Pueschel, M. [BC Berlin-Consult GmbH, Berlin (Germany)

    1995-11-01

    Sewage sludge is a solid-liquid mixture produced in each treatment step of a waste water treatment plant. The suitable manner of sludge treatment and disposal depends on the characteristics of the sludge such as its content of heavy metals and nutrient composition. To assess the different sludge treatment and disposal options besides the economical aspects effects on the environment must be considered. The emission of CO{sub 2} can serve as a possible approach for assessment. The dewatering and thermal drying approach for assessment. The dewatering and thermal drying causes the biggest part of CO{sub 2} emissions. They are at the same level as the CO{sub 2} which would be generated directly by total oxidation of the carbon contained in the sludge. The best way of sewage sludge disposal in accordance with the legal frame work, environmental impact and financial aspects is the co-combustion of sludge in cole power plants. The agricultural use of sludge with low heavy metal concentrations, however, is cheaper. (orig.) [Deutsch] Das Fest-Fluessig-Gemisch Klaerschlamm entsteht in jeder Reinigungsstufe einer Klaeranlage und muss anschliessend einer Behandlung zugefuehrt werden. Der Entsorgungsweg ist abhaengig von den Eigenschaften des Schlammes, wie z.B. seiner Schwermetallbelastung. Den Rahmen fuer die Klaerschlammentsorgung bilden die Regelungen des Abfallgesetzes, der Klaerschlammverordnung, der Duengemittelanwendungsverordnung, der TA Siedlungsabfall, des LAGA Merkblattes 10 (Kompost) und weiterer Verordnungen des Immissionsschutz- und Abfallrechts. Zur Bewertung der verschiedenen Entsorgungswege wurden neben den oekonomischen Aspekten auch die Auswirkungen der jeweiligen Verfahren auf die Umwelt beruecksichtigt. Es wurde fuer die oekologische Bewertung die CO{sub 2}-Emission des einzelnen Verfahrens herangezogen. Das Resultat des Vergleichs zeigt, dass der Co-Verbrennung der Vorzug zu geben ist. Bei geringen Schwermetallbelastungen bietet die landwirtschaftliche

  16. Influence of process operating parameters on dryness level and energy saving during wastewater sludge electro-dewatering.

    Science.gov (United States)

    Mahmoud, Akrama; Hoadley, Andrew F A; Conrardy, Jean-Baptiste; Olivier, Jérémy; Vaxelaire, Jean

    2016-10-15

    Electrically assisted mechanical dewatering, known as electro-dewatering (EDW), is an alternative emerging technology for energy-efficient liquid/solids separation in the dewatering of wastewater sludge. In this study, the performance of the electro-dewatering (EDW) process for activated wastewater sludge was investigated. The influence of the operating modes; being the timing of voltage (U-EDW) or current (I-EDW) application to either or both the filtration and compression stages, and the influence of the applied pressure (in successive 30 min pressure steps) were studied. The results showed that by delaying the application of the electric field to the filter cake compression stage, there was a potential saving in power consumption of around 10-12% in the case of U-EDW and about 30-46% in the case of I-EDW. The increase of the applied pressure from 0.5 to 12 bar during the filter cake compression stage leads to an increase in electro-dewatering kinetics. The results also reveal that at a low electric field level the increase of the processing pressure has a relatively pronounced effect on the dewatering process. At high levels of the electric field, a minimum processing pressure (4-6 bar) is required to improve the electrical contact between the electrode and the sludge and thus lower the energy consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. 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.

  18. 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

    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......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 characterise the changes in floc properties that led to settling and dewatering problems and to find reasons for this taking place, a comprehensive monitoring program was conducted during more than one year. The monitoring program included various measurements of floc settleability, floc strength and sludge...

  19. ZEOLITIZATION OF SEWAGE SLUDGE ASH WITH A FUSION METHOD

    Directory of Open Access Journals (Sweden)

    Jolanta Latosińska

    2016-11-01

    Full Text Available The study shows the results of zeolitization of municipal sewage sludge ash with the indirect fusion method followed by a hydrothermal method. The zeolitization of sewage sludge ash was conducted at the melting temperature of 550°C and the melting time of 60 minutes, crystallization temperatures of 60°C and 90°C, crystallization time of 6 hours and the SSA:NaOH ratio of 1:1.8; 1:1.4. The research of modified sewage sludge ashes included the observation of changes of ash particles surface and the identification of crystalized phases. The zeolitization of sewage sludge ash at the ratio of SSA:NaOH 1.0:1.4 did not cause the formation of zeolite phases. On the other hand, the zeolitization at the ratio of SSA:NaOH 1.0:1.8 resulted in the formation of desired zeolite phases such as zeolite Y (faujasite and hydroxysodalite. The presented method of sewage sludge ash zeolitization allows to obtain highly usable material. Synthesized zeolites may be used as adsorbents and ion exchangers. They can be potentially used to remove heavy metals as well as ammonia from water and wastewater.

  20. Hydrogen and syngas production from sewage sludge via steam gasification

    Energy Technology Data Exchange (ETDEWEB)

    Nipattummakul, Nimit [The Combustion Laboratory, Dept. of Mechanical Engineering, University of Maryland, College Park, MD (United States); The Waste Incineration Research Center, Dept. of Mechanical and Aerospace Engineering, King Mongkut' s University of Technology, North Bangkok (Thailand); Ahmed, Islam I.; Gupta, Ashwani K. [The Combustion Laboratory, Dept. of Mechanical Engineering, University of Maryland, College Park, MD (United States); Kerdsuwan, Somrat [The Waste Incineration Research Center, Dept. of Mechanical and Aerospace Engineering, King Mongkut' s University of Technology, North Bangkok (Thailand)

    2010-11-15

    High temperature steam gasification is an attractive alternative technology which can allow one to obtain high percentage of hydrogen in the syngas from low-grade fuels. Gasification is considered a clean technology for energy conversion without environmental impact using biomass and solid wastes as feedstock. Sewage sludge is considered a renewable fuel because it is sustainable and has good potential for energy recovery. In this investigation, sewage sludge samples were gasified at various temperatures to determine the evolutionary behavior of syngas characteristics and other properties of the syngas produced. The syngas characteristics were evaluated in terms of syngas yield, hydrogen production, syngas chemical analysis, and efficiency of energy conversion. In addition to gasification experiments, pyrolysis experiments were conducted for evaluating the performance of gasification over pyrolysis. The increase in reactor temperature resulted in increased generation of hydrogen. Hydrogen yield at 1000 C was found to be 0.076 g{sub gas} g{sub sample}{sup -1}. Steam as the gasifying agent increased the hydrogen yield three times as compared to air gasification. Sewage sludge gasification results were compared with other samples, such as, paper, food wastes and plastics. The time duration for sewage sludge gasification was longer as compared to other samples. On the other hand sewage sludge yielded more hydrogen than that from paper and food wastes. (author)

  1. 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)

  2. Influence of organic and inorganic flocculants on the formation of PCDD/Fs during sewage sludge incineration.

    Science.gov (United States)

    Lin, Xiaoqing; Li, Xiaodong; Lu, Shengyong; Wang, Fei; Chen, Tong; Yan, Jianhua

    2015-10-01

    Flocculants are widely used to improve the properties of sludge dewatering in industrial wastewater treatment. However, there have been no studies conducted on the influence of flocculants on the formation of polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) during sewage sludge incineration. This paper selected three typical kinds of flocculants, including polyacrylamide (PAM), poly-ferric chloride (PFC), and polyaluminum chloride (PAC) flocculant, to study their influences on the formation of PCDD/Fs during sewage sludge incineration. The results indicated that PAM flocculant, which is an organic flocculant, inhibited the formation of PCDD/Fs in sewage sludge incineration, while inorganic flocculant, such as PFC and PAC flocculant, promoted the formation. The most probable explanation is that the amino content in the PAM flocculant acted as an inhibitor in the formation of PCDD/Fs, while the chlorine content, especially the metal catalyst in the PFC and PAC flocculants, increased the formation rate. The addition of flocculants nearly did not change the distribution of PCDD/F homologues. The PCDFs contributed the most toxic equivalent (TEQ) value, especially 2, 3, 4, 7, 8-PeCDF. Therefore, the use of inorganic flocculants in industrial wastewater treatment should be further assessed and possibly needs to be strictly regulated if the sludge is incinerated. From this aspect, a priority to the use of organic flocculants should be given.

  3. Electron ray facilities for the pasteurization of sewage sludges

    International Nuclear Information System (INIS)

    Heuer, D.; Hofmann, E.G.

    1978-01-01

    Growing industrialization and the simultaneous increase in population density demand broad preventive measures in the area of waste water and sewage sludges. Electron irradiation is becoming an important tool for disinfection in this field. The AEG-Telefunken sludge pasteurization process works in continuous operation with homogenized sludge at electron energies between 1,0 to 1,5 MeV and a radiation dosage of 4 kJ/kg. The system offers the capabilities for an effective and costadvantageous disinfection of waste sludges of differing consistencies and origins and their harmless reuse as fertilizer in agriculture. (orig.) [de

  4. [Sewage sludge conditioning by bioleaching-dual PAC and PAM addition].

    Science.gov (United States)

    Liu, Chang-Geng; Zhang, Pan-Yue; Zeng, Guang-Ming; Liu, Yong-Gang

    2010-09-01

    Bioleaching-dual polyaluminum chloride (PAC) and polyacrylamide (PAM) addition was used to condition sewage sludge. The results showed that FeSO4 x 7H2O addition improved the bioleaching rate obviously with a fixed sulfur power dosage of 3 g x L(-1); when the FeSO4 x 7H2O dosage was 8 g x L(-1), the bioleaching lasted 1.5 d to decrease the sludge pH below 2. Bioleaching improved the sludge dewaterability significantly with a specific resistance to filtration (SRF) reduction of 77.52% from 6.45 x 10(10)s2 x g(-10 to 1.45 x 10(10)s2 x g(-1), but the bioleached sludge was still difficult to be dewatered. After adjusting the bioleached sludge pH to 6, PAC and PAM were used to enhance conditioning of the bioleached sludge. The results indicated that the optimal dosage was 200 mg x L(-1) for PAC or 50 mg x L(-1) for PAM when single chemical was used. When PAC and PAM were dually used, the optimal dosages of PAC and PAM were 100 mg x L(-1) and 25 mg x L(-1), respectively; SRF and moisture of sludge cake reduced to 2.02 x 10(8) s2 x g(-1) and 74.81%, respectively, showing good dewaterability of the treated sludge. Compared with the single use of PAC and PAM, the dual use of PAC and PAM showed the advantages of lower cost and better conditioning effect.

  5. Soil Microbial Functional and Fungal Diversity as Influenced by Municipal Sewage Sludge Accumulation

    OpenAIRE

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy; Jezierska-Tys, Stefania; Nwaichi, Eucharia Oluchi

    2014-01-01

    Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS) and from a sewage sludge landfill that was 3 m from a SS landfill (SS3) were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Avera...

  6. Sewage sludge treatment and disposal. Experiences and perspectives; Klaerschlammbehandlung und -entsorgung. Erfahrungen und Perspektiven

    Energy Technology Data Exchange (ETDEWEB)

    Dichtl, N.; Mueller, J. [comps.] [Technische Univ. Braunschweig (Germany). Inst. fuer Siedlungswasserwirtschaft

    1997-09-01

    Topics of the proceedings are: sewage sludge treatment and sewage sludge disposal by means of: thermal treatment, fermentation, composting, wet oxidation, hydrolysis, disposal in agriculture, economical aspects of sewage sludge treatment. This book deals with theoretical aspects and practical examples. (SR)

  7. Study of heavy metal in sewage sludge and in Chinese cabbage ...

    African Journals Online (AJOL)

    The study was performed to investigate the heavy metal content and availability for crops in sewage sludge and its accumulation in Chinese cabbage grown in sewage sludge amended soil. We determined the total and chemical fraction of As, Cr, Cd, Pb, Ni, Cu, Zn, Fe, Mg and Mn in sewage sludge and the total content of ...

  8. 78 FR 34918 - Direct Final Approval of Sewage Sludge Incinerators State Plan for Designated Facilities and...

    Science.gov (United States)

    2013-06-11

    ... Approval of Sewage Sludge Incinerators State Plan for Designated Facilities and Pollutants; Indiana AGENCY... to control air pollutants from ``Sewage Sludge Incinerators'' (SSI). The Indiana Department of... unit,'' in part, as any device that combusts sewage sludge for the purpose of reducing the volume of...

  9. Application of radiation technology to sewage sludge processing: A review

    International Nuclear Information System (INIS)

    Wang Jianlong; Wang Jiazhuo

    2007-01-01

    Sewage sludge is unwanted residual solid wastes generated in wastewater treatment and its management is one of the most critical environmental issues of today. The treatment and disposal of sludge contribute a considerable proportion of the cost for running a wastewater treatment plant. The increasing amount of swage sludge and more and more legislative regulation of its disposal have stimulated the need for developing new technologies to process sewage sludge efficiently and economically. One ideal consideration is to recycle it after proper treatment. Radiation technology is regarded to be a promising alternative for its high efficiency in pathogen inactivation, organic pollutants oxidation, odor nuisance elimination and some other characteristics enhancement, which will facilitate the down-stream process of sludge treatment and disposal. Here we present a brief review of application of radiation technology on sewage sludge processing. Some basic information of two currently available irradiation systems and fundamental radiation chemistry are introduced firstly; then the world-wide application of this promising technology is reviewed; various effects of radiation on sludge is discussed in detail; and some concluding remarks are given and some future directions are also proposed

  10. Urban Sewage Sludge, Sustainability, and Transition for Eco-City

    DEFF Research Database (Denmark)

    Ren, Jingzheng; Liang, Hanwei; Chan, Felix T. S.

    2017-01-01

    The treatment of urban sewage sludge is of vital importance for mitigating the risks of environmental contaminations, and the negative effects on human health. However, there are usually various different technologies for the treatment of urban sewage sludge; thus, it is difficult for decision......-makers/stakeholders to select the most sustainable technology among multiple alternatives. This study aims at developing a generic multi-criteria decision support framework for sustainability assessment of the technologies for the treatment of urban sewage sludge. A generic criteria system including both hard and soft criteria...... in economic, environmental, social and technological aspects was developed for sustainability assessment. The improved analytic hierarchy process method, namely Best-Worst method, was employed to determine the weights of the criteria and the relative priorities of the technologies with respect to the soft...

  11. Bioleaching of heavy metals from sewage sludge using Acidithiobacillus thiooxidans

    Science.gov (United States)

    Wen, Ye-Ming; Lin, Hong-Yan; Wang, Qing-Ping; Chen, Zu-Liang

    2010-11-01

    Acidithiobacillus thiooxidans was isolated from sewage sludge using the incubation in the Waksman liquor medium and the inoculation in Waksman solid plate. It was found that the optimum conditions of the bioleaching included solid concentration 2%, sulfur concentration 5 gṡL-1 and cell concentration 10%. The removal efficiency of Cr, Cu, Pb and Zh in sewage sludge, which was obtained from waste treatment plant, Jinshan, Fuzhou, was 43.65%, 96.24%, 41.61% and 96.50% in the period of 4˜10 days under the optimum conditions, respectively. After processing using the proposed techniques, the heavy metals in sewage sludge did meet the requirement the standards of nation.

  12. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-10-01

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

  14. Combined treatment of solar energy and gamma irradiation to eliminate pathogenic bacteria in dewatered sludge

    International Nuclear Information System (INIS)

    Hilmy, N.; Harsoyo, S.; Suwirma, S.

    1987-01-01

    Combined treatment of solar energy and gamma irradiation to eliminate pathogenic bacteria in dewatered sludge. A combined treatment of solar energy and gamma irradiation has been done to eliminate the pathogenic microbes contaminating dewatered sludge. Samples were collected during dry season, i.e. from June to September 1985. To reduce the water content from 70% to 20%, solar energy from sun rays was used, i.e. from 9 a.m. to 2 p.m. for 4 days. Total bacterial count coliform bacteria Escherichia coli, Fecal Streptococcus, Enterobacteriaceae, and Pseudomonas sp were found to be 7.4x10 8 per g, 4.1x10 3 per g, 4.5x10 2 per g, 3.1x10 5 per g, 3.6x10 4 per g, and 5.4x10 3 per g of samples respectively. The combined treatment could reduce the irradiation dose needed to eliminate the pathogenic microbes of samples investigated from 6 to 2 kGy. (author). 5 figs, 11 refs

  15. A novel acrylamide-free flocculant and its application for sludge dewatering.

    Science.gov (United States)

    Lu, Lianghua; Pan, Zhida; Hao, Nan; Peng, Wenqing

    2014-06-15

    In the present research, copolymers of methyl acrylate (MA) with anionic or cationic monomers were synthesized via emulsion polymerization, and used as sludge dewatering aids in wastewater treatment. The copolymerization of different stoichiometry of two monomers afforded a variety of water soluble copolymers with charge densities ranging from 40% to 80%, which align with the charge density of current flocculant products. These copolymers resemble current commercial products, but provide a greener solution by eliminating acrylamide monomer, which is a suspected carcinogen. High molecular weight copolymers were achieved by applying powder-like synthesis process with intrinsic viscosity of final products as high as 12.98 dl/g for anionic flocculant and 10.74 dl/g for cationic flocculant. The copolymers of methyl acrylate and [2-(Acryloyloxy)ethyl]trimethylammonium chloride (AETAC) with 55% charge density exhibited comparable performance in clay settling test, real water jar test, and sludge dewatering, when compared to AM-based commercial product in the real wastewater treatment application. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Thermophilic versus Mesophilic Anaerobic Digestion of Sewage Sludge: A Comparative Review

    Directory of Open Access Journals (Sweden)

    Getachew D. Gebreeyessus

    2016-06-01

    Full Text Available During advanced biological wastewater treatment, a huge amount of sludge is produced as a by-product of the treatment process. Hence, reuse and recovery of resources and energy from the sludge is a big technological challenge. The processing of sludge produced by Wastewater Treatment Plants (WWTPs is massive, which takes up a big part of the overall operational costs. In this regard, anaerobic digestion (AD of sewage sludge continues to be an attractive option to produce biogas that could contribute to the wastewater management cost reduction and foster the sustainability of those WWTPs. At the same time, AD reduces sludge amounts and that again contributes to the reduction of the sludge disposal costs. However, sludge volume minimization remains, a challenge thus improvement of dewatering efficiency is an inevitable part of WWTP operation. As a result, AD parameters could have significant impact on sludge properties. One of the most important operational parameters influencing the AD process is temperature. Consequently, the thermophilic and the mesophilic modes of sludge AD are compared for their pros and cons by many researchers. However, most comparisons are more focused on biogas yield, process speed and stability. Regarding the biogas yield, thermophilic sludge AD is preferred over the mesophilic one because of its faster biochemical reaction rate. Equally important but not studied sufficiently until now was the influence of temperature on the digestate quality, which is expressed mainly by the sludge dewateringability, and the reject water quality (chemical oxygen demand, ammonia nitrogen, and pH. In the field of comparison of thermophilic and mesophilic digestion process, few and often inconclusive research, unfortunately, has been published so far. Hence, recommendations for optimized technologies have not yet been done. The review presented provides a comparison of existing sludge AD technologies and the gaps that need to be filled so

  17. The key to sewage sludge disposal. Wohin mit dem Klaerschlamm

    Energy Technology Data Exchange (ETDEWEB)

    Florin, G. (Sulzer-Escher Wyss GmbH, Fliessbett-Technik, Ravensburg (Germany))

    1994-01-01

    At the sewage treatment plant in Dornbirn (Austria), the quality of the treated effluent is so good that trout can be seen swimming in the outfall. Nevertheless, the quantity of removed polluting matter has posed a real problem for the persons responsible. In their efforts to find a means for reducing the volume of sewage sludge, they came across the so-called fluidbed drying process. (orig.)

  18. Transformation of Silver Nanoparticles in Sewage Sludge during Incineration.

    Science.gov (United States)

    Meier, Christoph; Voegelin, Andreas; Pradas del Real, Ana; Sarret, Geraldine; Mueller, Christoph R; Kaegi, Ralf

    2016-04-05

    Silver nanoparticles (Ag-NP) discharged into the municipal sewer system largely accumulate in the sewage sludge. Incineration and agricultural use are currently the most important strategies for sewage sludge management. Thus, the behavior of Ag-NP during sewage sludge incineration is essential for a comprehensive life cycle analysis and a more complete understanding of the fate of Ag-NP in the (urban) environment. To address the transformation of Ag-NP during sewage sludge incineration, we spiked metallic Ag(0)-NP to a pilot wastewater treatment plant and digested the sludge anaerobically. The sludge was then incinerated on a bench-scale fluidized bed reactor in a series of experiments under variable conditions. Complementary results from X-ray absorption spectroscopy (XAS) and electron microscopy-energy dispersive X-ray (EM-EDX) analysis revealed that Ag(0)-NP transformed into Ag2S-NP during the wastewater treatment, in agreement with previous studies. On the basis of a principal component analysis and subsequent target testing of the XAS spectra, Ag(0) was identified as a major Ag component in the ashes, and Ag2S was clearly absent. The reformation of Ag(0)-NP was confirmed by EM-EDX. The fraction of Ag(0) of the total Ag in the ashes was quantified by linear combination fitting (LCF) of XAS spectra, and values as high as 0.8 were found for sewage sludge incinerated at 800 °C in a synthetic flue gas atmosphere. Low LCF totals (72% to 94%) indicated that at least one relevant reference spectrum was missing in the LCF analysis. The presence of spherical Ag-NP with a diameter of incineration, as demonstrated in this study, needs to be considered in the life cycle assessment of engineered Ag-NP.

  19. Enhancement of biogas production from sewage sludge by addition of grease trap sludge

    International Nuclear Information System (INIS)

    Grosser, A.; Neczaj, E.

    2016-01-01

    Highlights: • Addition of grease trap sludge is interesting option for sewage sludge digestion. • Co-digestion of grease trap sludge and sewage sludge improved efficiency of process. • The anaerobic digestion can be carried out at short hydraulic retention time. • Long chain fatty acids concentration was below the ranges for inhibition of anaerobic digestion. - Abstract: Despite having many benefits, a low degree of volatile solids removal as well as long retention time are the main factors limiting the performance of the anaerobic digestion. Co-digestion of sewage sludge with other organic waste (for example fat rich materials) is one of the few potential ways to enhance the performance of the anaerobic digestion. In this article, the effects of adding fatty rich materials on the performance and stability of semi-continuous anaerobic digestion of sewage sludge were investigated on a 6 l laboratory-scale reactor (working volume equal to 5.5 l). The reactor was operated in a semi-continuous mode with a hydraulic retention time of 10 days. The data presented in this paper relate to the period in which the grease trap sludge accounted for 10, 12, 14, 16 and 18% of the mixture on the volatile solids basis. The results clearly indicate that the addition of fat rich materials like grease trap sludge can lead to a satisfactory increase in biogas yield in digester treating sewage sludge. The results showed that co-digestion can enhance the biogas yield by 28–82% compared to anaerobic digestion of sewage sludge alone (control sample). Moreover, the addition of grease trap sludge to digesters resulted in increased volatile solids removal from 44.38% (control sample) to 57.77% (feedstock with 14% addition of grease trap sludge). It was found that the increase of grease trap sludge in the feedstock had a direct impact on the biogas production and methane yield. This proposal has also been confirmed by statistical analysis such as Pearson correlation coefficients and

  20. Life cycle assessment of sewage sludge management: A review

    DEFF Research Database (Denmark)

    Yoshida, Hiroko; Christensen, Thomas Højlund; Scheutz, Charlotte

    2013-01-01

    In this article, 35 published studies on life cycle assessment (LCA) of sewage sludge were reviewed for their methodological and technological assumptions. Overall, LCA has been providing a flexible framework to quantify environmental impacts of wastewater and sewage sludge treatment and disposal...... and how they were estimated in the analysis. In order to reduce these choice uncertainties, consolidation of the modelling approach in the following area are recommended: quantification of fugitive gas emissions and modelling of disposal practices. Besides harmonization of the key technical assumptions...

  1. Phosphorus recovery from sewage sludge by an electrokinetic process

    DEFF Research Database (Denmark)

    Ribeiro, A.B.; Couto, N.; Mateus, E.P.

    to supply P for the next ca. 80 years. Additionaly, the quality of this raw material has deteriorated due to contamination, which has increased processing costs of mineral P fertilizers. The recovery of nutrients, like P, from secondary resources urges. Sewage sludge (SS) and sewage sludge ash (SSA) from...... waste water treatment plants (WWTP) may contain contaminants or unwanted elements regarding specific applications, but they also contain secondary resources of high value. Using these ash as a P resource, while removing the contaminants, seems a sustainable option. The electrokinetic (EK) process can....... This communication aims to discuss preliminary results of the feasibility of EK process to recover P from WWTP target wastes....

  2. 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.

  3. Leachability of fired clay brick incorporating with sewage sludge waste

    Science.gov (United States)

    Kadir, Aeslina Abdul; Salim, Nurul Salhana Abdul; Sarani, Noor Amira; Rahmat, Nur Aqma Izurin; Abdullah, Mohd Mustafa Al Bakri

    2017-09-01

    Sewage sludge is sewerage from wastewater treatment plants that generates millions tons of sludge ever year. Regarding this activity, it causes lack management of waste which is harmful to the surrounding conditions. Therefore, this study is focuses on the incorporation of sewage sludge waste into fired clay brick to provide an option of disposal method, producing adequate quality of brick as well as limiting the heavy metal leachability to the environment. Sewage sludge brick (SSB) mixtures were incorporated with 0%, 1%, 5%, 10%, 20% and 30% of sewage sludge waste (SSW). Heavy metals of crushed SSB were determined by using Toxicity Characteristic Leaching Procedure (TCLP) according to Method 1311 of United State Environment Protection Agency (USEPA) standard. From the results obtained, up to 20% of SSW could be incorporated into fired clay brick and comply with the USEPA standard. Therefore, this study revealed that by incorporating SSW into fired clay brick it could be an alternative method to dispose the SSW and also could act as a replacement material for brick manufacturing with appropriate mix and design.

  4. Agricultural yields of irradiated sewage sludge; Rendimiento agricola de barros cloacales irradiados

    Energy Technology Data Exchange (ETDEWEB)

    Magnavacca, Cecilia; Miranda, E; Sanchez, M [Comision Nacional de Energia Atomica, Ezeiza (Argentina). Centro Atomico Ezeiza

    1999-07-01

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

  5. The sanitary effect of gamma irradiation on sewage sludge

    International Nuclear Information System (INIS)

    Hess, E.; Breer, C.

    1975-01-01

    Sludge contains Salmonellae in more than 90% of samples. The maximum number reaches 10 7 per liter. Neither aerobic stabilization nor anaerobic digestion significantly reduces the contamination with Salmonellae. Moreover, Salmonellae in sewage sludge spread on grass may survive up to 72 weeks. Fertilizing with unsanitized sludge may therefore lead to transmission from plant to animal. Sanitizing of sludge to be used as fertilizer is therefore urgent. The sanitary effect of pasteurisation and of gamma irradiation on sewage sludge was investigated. For this the number of Enterobacteriaceae before and after irradiation in 259 specimens of sludge from 44 different sewage disposal plants was examined. The doses applied were 100, 200, 300, 400 and sometimes 500 krad. A linear reduction of Enterobacteriaceae was achieved with increasing radiation doses. A dose of 300 krad resulted in a death rate of 10 4 - 10 8 , occasionally 10 9 Enterobacteriaceae. Less than 10 Enterobacteriaceae per gramm were found in 97.2% of the samples irradiated with 300 krad. The effect found in the above mentioned model experiments could be perfectly confirmed under practical conditions in the irradiation plant of Geiselbullach. The sanitary effect of gamma irradiation with 300-350 krad, determined by Enterobacteriaceae reduction, was equivalent to the effect of heat treatment by pasteurisation. (orig./MG) [de

  6. Soil application of sewage sludge stabilized with steelmaking slag and its effect on soil properties and wheat growth.

    Science.gov (United States)

    Samara, Eftihia; Matsi, Theodora; Balidakis, Athanasios

    2017-10-01

    The effect of sewage sludge, stabilized with steelmaking slag, on soil chemical properties and fertility and on wheat (Triticum aestivum L.) growth was evaluated. Dewatered sewage sludge [75% (wet weight basis)] stabilized with steelmaking slag (25%) and three soils with different pH values were used in a pot experiment with winter wheat. The following treatments were applied: (i) sludge addition of 30gkg -1 (≈ 120Mgha -1 , rate equivalent to the common inorganic N fertilization for wheat, based on sludge's water soluble NO 3 -N), (ii) sludge addition of 10gkg -1 (≈ 40Mgha -1 , rate equivalent to the common inorganic N fertilization for wheat, based on sludge's Kjeldahl-N), (iii) addition of the common inorganic N fertilization for wheat (120kgNha -1 ) as NH 4 NO 3 , (iv) control (no fertilizer, no sludge). Sludge application at both rates to all soils resulted in a significant increase of pH, electrical conductivity of the saturation extract (EC se ) and soil available NO 3 -N and P, in comparison to the other two treatments and this increase remained constant till the end of the pot experiment. In sludge treatments pH did not exceed the critical value of 8.5, whereas EC se , although it did not reach the limit of 4dSm -1 , exceeded the value of 2dSm -1 at the rate of 30gkg -1 . Concentrations of heavy metals, which regulate the agronomic use of sewage sludge according to the established legislation, ranged from not detectable to lower than the respective permissible levels. Both rates of sludge's addition in all soils improved wheat's growth, as judged by the significant increase of the aboveground biomass yield and the total plant uptake of almost all nutrients, compared to the other two treatments. It was concluded that sewage sludge stabilized with steelmaking slag could be used in agriculture, applied at rates based on sludge's Kjeldahl-N content and crop's demand for N. However, potential environmental impacts must also be considered. Copyright © 2017

  7. The pilot plant in Geiselbullach for the gamma irradiation of sewage sludge - design, operation experience and cost calculations

    International Nuclear Information System (INIS)

    Lessel, T.; Hennig, E.

    1976-01-01

    The pilot plant for sewage sludge irradiation in Geiselbullach near Munich has been in operation from July '73 to October '75 with a capacity of 30 m 3 per day. Successful experiences during this period resulted in an increase of the installed radiation energy and in several improvements for the technique and the efficiency. From December 1975 on the plant has been operating with a daily capacity of 120 m 3 of sludge per day. The experience with this plant brought several problems which caused interruptions of the continuous operation and that had to be solved with new measures. But although the facility at Geiselbullach is a pilot plant the availability was more than 350 days per year. Due to the simple design of the plant and of the fully automatic operation no special trained personal is necessary for the maintenance. Beside the effect of the hygienization the irradiation caused improved sedimentation properties of the sludge. Presently investigations are undertaken to prove better mechanical sludge dewatering properties. Cost calculations resulted in about DM 2.30 for operating expenses and DM 2.25 for capital costs per m 3 of sludge for the fully charged plant. The capital costs will be less in commercial plants. The conditioning effect on the sludge by the irradiation means savings of about DM 1.00 per m 3 . The irradiation of sewage sludge proved to be possible at about equal costs compared to the wellknown heat treatment (pasteurization at 70 0 C during 30 minutes.). Further investigations have to be done to overcome the contrary development of the plant capacity, limited by the decaying radiation energy and the normally rising sludge quantities of a sewage water treatment plant. (author)

  8. 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

  9. Recent developments in the Sandia Laboratories' sewage sludge irradiation program

    International Nuclear Information System (INIS)

    Sivinski, H.D.; Brandon, J.R.; Morris, M.E.; Neuhauser, K.S.; Ward, R.L.; McCaslin, B.; Smith, G.S.

    1977-11-01

    Pathogen reduction studies have shown that a 1 Mrad treatment (or less at elevated temperatures) is very effective in eliminating pathogenic bacteria and viable parasite ova in liquid sludges. Heat is effective in reducing levels not only of pathogenic bacteria and Ascaris ova, but viruses as well. Ammonia has been shown to be virucidal to poliovirus and several other enteric viruses. Sludge processing costs are seen to be marginally competitive with heat treatment for liquid sludges and relatively economical for composted or dried sludges. Physical/chemical effects studies have shown that the effects of irradiation of sludges on dewatering properties are not significant when compared to polymers, nor is the combined effect synergistic. Dried, irradiated undigested sludge has been shown to be of significant nutritional value when used as a feed supplement for sheep and cattle, as well as in agronomic uses. No significant harmful effects have been demonstrated in the feeding program thus far. Product enhancement studies are currently under way, including schemes for removing nitrogen from effluent streams for addition as ammonium salts to sludges

  10. Acceleration of organic removal and electricity generation from dewatered oily sludge in a bioelectrochemical system by rhamnolipid addition.

    Science.gov (United States)

    Zhang, Yunshu; Zhao, Qingliang; Jiang, Junqiu; Wang, Kun; Wei, Liangliang; Ding, Jing; Yu, Hang

    2017-11-01

    Conversion of biomass energy of dewatered oily sludge to electricity is the rate-limiting process in bioelectrochemical system (BES). In this study, 2mgg -1 rhamnolipids were added to dewatered oily sludge, resulting in a significant enhancement in maximum power density from 3.84±0.37 to 8.63±0.81Wm -3 , together with an increase in total organic carbon (TOC) and total petroleum hydrocarbon (TPH) removal from 24.52±4.30 to 36.15±2.79mgg -1 and 29.51±3.30 to 39.80±2.47mgg -1 , respectively. Rhamnolipids can also enhance the solubilization and promote the hydrolysis of dewatered oily sludge with increases in SOCD from 14.93±2.44 to 18.40±0.08mgg -1 and VFAs from 1.02±0.07 to 1.39±0.12mgg -1 . Furthermore, bacteria related to substrate degradation were predominant in dewatered oily sludge, and bacteria related to the sulfate/sulfide cycle were significantly enriched by rhamnolipid addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    International Nuclear Information System (INIS)

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

    1974-06-01

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

  12. 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

  13. Sewage sludge and how to sell it

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, I M

    1977-10-01

    Largo, Florida dries its sludge and sells it as fertilizer for $80 to $169/T. The sludge processing plant capable of turning common sludge into a dry, pelletized soil conditioner was only slightly more expensive than the previously proposed concrete drying beds which would have required disposal of the dried residue. The city's experience in setting up the plant and marketing the finished product is discussed. The true advantage of selling heat-dried sludge is that residents of the surrounding area, knowing the value of the product to their lawns and shrubs, will provide the transportation for the product and the physical labor to spread it over an area wider than most municipalities could afford to own or operate. The current production cost of $140/T is high, but the addition of a sludge prethickener-conditioner process and expected future economies of scale as the volume of sludge treated increases should lower per ton costs.

  14. Fast pyrolysis of lignin, macroalgae and sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Trinh, N.T.

    2013-04-15

    Non-conventional biomass feedstock may also be applicable for fast pyrolysis processes. Among the forms of non-conventional biomasses, macroalgae, lignin (industrial residue) and sewage sludge may be attractive materials due to their low price, non-competitiveness with food crops and the possible utilization of solid wastes. Besides, a fast pyrolysis process can be used as a process to densify the biomass and produce bioslurry, a mixture of bio-oil and pyrolytic char. The bioslurry is found to be a possible feedstock for pressurized gasification plants. Thus, the aims of this project are to investigate fast pyrolysis properties of lignin, sewage sludge and macroalgae on a lab scale PCR and characterize their bio-oil properties. Bioslurry properties with respect to use as a feedstock for pressurized gasification is also investigated. Lignin and sewage sludge PCR pyrolysis provided bio-oil yields of 47 and 54 wt% daf, and oil energy recovery of 45 and 50 %, respectively. While the macroalgae PCR pyrolysis showed promising results with an organic oil yield of 65 wt% daf and an oil energy recovery of 76 %. The HHV of the lignin, sewage sludge and macroalgae oils were 29.7, 25.7 and 25.5 MJ/kg db respectively, and that are higher than that of typical bioiv oil from conventional biomasses (23-24 MJ/kg db). Almost all metals feedstock contents were contained in the chars at temperatures of 550 - 575 deg. C for lignin, sewage sludge and macroalgae PCR pyrolysis. Due to high feedstock nitrogen and sulfur contents, also a high level of nitrogen and sulfur of macroalgae and sewage sludge oils were observed compared to conventional bio-oil and this may limit their further industrial applications. The lignin char had a high proportion of small size particles, a HHV of 21 MJ/kg db and were almost free of chloride and sulfur, thus it is considered as a promising fuel for gasification or combustion; whereas macroalgae and sewage sludge chars containing high amounts of

  15. Evaluation of selected sewage sludge gasification technological parameters

    Science.gov (United States)

    Gałko, Grzegorz; Król, Danuta

    2018-02-01

    Evaluation of selected sewage sludge gasification technological parameters was shown in this paper. Degree of carbon conducted in combustible substance and syngas efficiency (technological readiness coefficient) in accordance with equations were calculated. Enthalpy of individual compounds formation and energy balance were calculated in accordance with rule of Hess.

  16. Biodegradation of Lignocelluloses in Sewage Sludge Composting and Vermicomposting

    Directory of Open Access Journals (Sweden)

    Hosein Alidadi

    2012-08-01

    Full Text Available Please cite this article as: Alidadi H, Najafpour AA, Vafaee A, Parvaresh A, Peiravi R. Biodegradation of lignocelluloses in sewage sludge composting and vermicomposting. Arch Hyg Sci 2012;1(1:1-5.   Aims of the Study: The aim of this study was to determine the amount of lignin degradation and biodegradation of organic matter and change of biomass under compost and vermicomposting of sewage sludge. Materials & Methods: Sawdust was added to sewage sludge at 1:3 weight bases to Carbon to Nitrogen ratio of 25:1 for composting or vermicomposting. Lignin and volatile solids were determined at different periods, of 0, 10, 30, 40 and 60 days of composting or vermicomposting period to determine the biodegradation of lignocellulose to lignin. Results were expressed as mean of two replicates and the comparisons among means were made using the least significant difference test calculated (p <0.05. Results: After 60 days of experiment period, the initial lignin increased from 3.46% to 4.48% for compost and 3.46% to 5.27% for vermicompost. Biodegradation of lignocellulose was very slow in compost and vermicompost processes. Vermicomposting is a much faster process than compost to convert lignocellulose to lignin (p <0.05. Conclusions: The organic matter losses in sewage sludge composting and vermicomposting are due to the degradation of the lignin fractions. By increasing compost age, the amount of volatile solids will decrease.

  17. A steady state model for anaerobic digestion of sewage sludges ...

    African Journals Online (AJOL)

    A steady state model for anaerobic digestion of sewage sludge is developed that comprises three sequential parts – a kinetic part from which the % COD removal and ... and a carbonate system weak acid/base chemistry part from which the digester pH is calculated from the partial pressure of CO2 and alkalinity generated.

  18. SEWAGE SLUDGE AS AN INGREDIENT IN FERTILIZERS AND SOIL SUBSTITUTES

    Directory of Open Access Journals (Sweden)

    Anna Grobelak

    2016-06-01

    Full Text Available In Poland, sludge management especially in medium and small sewage treatment plants is still a significant problem. According to data from the Central Statistical Office and the report on the implementation of the National Urban Wastewater Treatment Program (in polish KPOŚK land application of sewage sludge remains one of the main methods, although there has been considerable interest known: 'application for other purposes ", where the preparation of composts and fertilizers is included. The use of fertilizer produced from sewage sludge (compost, granules, organic and mineral fertilizers, is regulated by the Act on fertilizers and fertilization, and the relevant implementing rules. For example, they define the test procedure (concerning the quality of fertilizers to enable appropriate permissions to market this type of fertilizers. There is still only several technologies existing on the Polish market dedicated to production of fertilizers in advanced technologies of sewage sludge treatment. Usually the treatment plants are trying to obtain the necessary certificates for generated fertilizers (including composts, or soils substitutes. The advantages of these technologies should be no doubt: the loss of waste status, ability to store the fertilizer and unlimited transportation between areas, sanitization of the product (as a result of the use of calcium or sulfur compounds or temperature should be an alternative for drying technology. While the disadvantages are primarily the investment costs and time consuming certification procedures. However, these solutions enable to maintain the organic matter and phosphorus as well as greater control over possible pollution introduced into the soil.

  19. Utilisation of Electrodialytically Treated Sewage Sludge Ash in Mortar

    DEFF Research Database (Denmark)

    Kappel, Annemette; Pares Viader, Raimon; Kowalski, Krzysztof Piotr

    2018-01-01

    Phosphorous is a scarce resource and there is a need to develop methods for recovery of this irreplaceable nutrient from secondary resources, e.g. from sewage sludge ash (SSA). Today SSA is most often disposed of and the resource is lost. In the present study, about 90% phosphorous was recovered...

  20. Land Application of Sewage Effluents and Sludges: Selected Abstracts.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Research and Development.

    This report contains 568 selected abstracts concerned with the land application of sewage effluents and sludges. The abstracts are arranged in chronological groupings of ten-year periods from the l940's to the mid-l970's. The report also includes an author index and a subject matter index to facilitate reference to specific abstracts or narrower…

  1. Toluene in sewage and sludge in wastewater treatment plants.

    Science.gov (United States)

    Mrowiec, Bozena

    2014-01-01

    Toluene is a compound that often occurs in municipal wastewater ranging from detectable levels up to 237 μg/L. Before the year 2000, the presence of the aromatic hydrocarbons was assigned only to external sources. The Enhanced Biological Nutrients Removal Processes (EBNRP) work according to many different schemes and technologies. For high-efficiency biological denitrification and dephosphatation processes, the presence of volatile fatty acids (VFAs) in sewage is required. VFAs are the main product of organic matter hydrolysis from sewage sludge. However, no attention has been given to other products of the process. It has been found that in parallel to VFA production, toluene formation occurred. The formation of toluene in municipal anaerobic sludge digestion processes was investigated. Experiments were performed on a laboratory scale using sludge from primary and secondary settling tanks of municipal treatment plants. The concentration of toluene in the digested sludge from primary settling tanks was found to be about 42,000 μg/L. The digested sludge supernatant liquor returned to the biological dephosphatation and denitrification processes for sewage enrichment can contain up to 16,500 μg/L of toluene.

  2. Greenhouse gases emissions accounting for typical sewage sludge digestion with energy utilization and residue land application in China

    Energy Technology Data Exchange (ETDEWEB)

    Niu Dongjie, E-mail: niudongjie@tongji.edu.cn [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China); UNEP-Tongji Institute of Environment for Sustainable Development, 1239 Siping Road, Shanghai 200092 (China); Huang Hui [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China); Dai Xiaohu [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China); National Engineering Research Center for Urban Pollution Control, Shanghai 200092 (China); Zhao Youcai [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer GHGs emissions from sludge digestion + residue land use in China were calculated. Black-Right-Pointing-Pointer The AD unit contributes more than 97% of total biogenic GHGs emissions. Black-Right-Pointing-Pointer AD with methane recovery is attractive for sludge GHGs emissions reduction. - Abstract: About 20 million tonnes of sludge (with 80% moisture content) is discharged by the sewage treatment plants per year in China, which, if not treated properly, can be a significant source of greenhouse gases (GHGs) emissions. Anaerobic digestion is a conventional sewage sludge treatment method and will continue to be one of the main technologies in the following years. This research has taken into consideration GHGs emissions from typical processes of sludge thickening + anaerobic digestion + dewatering + residue land application in China. Fossil CO{sub 2}, biogenic CO{sub 2}, CH{sub 4,} and avoided CO{sub 2} as the main objects is discussed respectively. The results show that the total CO{sub 2}-eq is about 1133 kg/t DM (including the biogenic CO{sub 2}), while the net CO{sub 2}-eq is about 372 kg/t DM (excluding the biogenic CO{sub 2}). An anaerobic digestion unit as the main GHGs emission source occupies more than 91% CO{sub 2}-eq of the whole process. The use of biogas is important for achieving carbon dioxide emission reductions, which could reach about 24% of the total CO{sub 2}-eq reduction.

  3. Greenhouse gases emissions accounting for typical sewage sludge digestion with energy utilization and residue land application in China

    International Nuclear Information System (INIS)

    Niu Dongjie; Huang Hui; Dai Xiaohu; Zhao Youcai

    2013-01-01

    Highlights: ► GHGs emissions from sludge digestion + residue land use in China were calculated. ► The AD unit contributes more than 97% of total biogenic GHGs emissions. ► AD with methane recovery is attractive for sludge GHGs emissions reduction. - Abstract: About 20 million tonnes of sludge (with 80% moisture content) is discharged by the sewage treatment plants per year in China, which, if not treated properly, can be a significant source of greenhouse gases (GHGs) emissions. Anaerobic digestion is a conventional sewage sludge treatment method and will continue to be one of the main technologies in the following years. This research has taken into consideration GHGs emissions from typical processes of sludge thickening + anaerobic digestion + dewatering + residue land application in China. Fossil CO 2 , biogenic CO 2 , CH 4, and avoided CO 2 as the main objects is discussed respectively. The results show that the total CO 2 -eq is about 1133 kg/t DM (including the biogenic CO 2 ), while the net CO 2 -eq is about 372 kg/t DM (excluding the biogenic CO 2 ). An anaerobic digestion unit as the main GHGs emission source occupies more than 91% CO 2 -eq of the whole process. The use of biogas is important for achieving carbon dioxide emission reductions, which could reach about 24% of the total CO 2 -eq reduction.

  4. Use of radiation hygienised municipal sewage sludge as a soil conditioner to enhance agricultural productivity

    International Nuclear Information System (INIS)

    Shah, M.R.; Nareshkumar; Sabharwal, S.

    2009-01-01

    This paper presents a report on the applications that have been developed and demonstrated in the radiation hygienisation of municipal sewage sludge for use in the agriculture as value added manure. Radiation hygienization process effectively eliminates the pathogenic bacteria present in the sewage sludge. Application of sludge to agricultural land enhances the yield and quality of agricultural products due to macronutrients and micronutrients present in the sludge. The process benefits municipal sewage treatment plant authorities as well as farming community. (author)

  5. The effects of pelleted sewage sludge on Norway spruce establishment and nitrogen dynamics

    International Nuclear Information System (INIS)

    Johannesson, Anders

    1999-01-01

    In Sweden there is a big resource in unutilised sewage sludge. Studies have shown that application of municipal sewage sludge can improve forest productivity and planting environment. This study is examining the effects of two types of pelleted sewage sludge (pure sludge and a mixture of sludge and domestic wastes compost) on nitrogen turnover. Large differences were found in the fertilisation effect of the different treatments. The pure sewage sludge pellets treatment showed significant increases for NH 4 -accumulation, nitrification and NO 3 -leaching in the top 10 cm of the soil. Uptake of nitrogen was increased in spruce plants and vegetation. The mixed sludge/domestic waste pellets treatment showed indications of a minor initial release of nitrogen. This is seen as a small but significant initial increase in soil nitrification. These results suggest that the pure sewage sludge pellet is an adequate nitrogen fertiliser. The mixed sludge though is inadequate at least in the short run

  6. Sewage sludge - arisings, composition, disposal capacities; Klaerschlamm - Mengen, Zusammensetzung, Entsorgungskapazitaeten

    Energy Technology Data Exchange (ETDEWEB)

    Faulstich, M.; Rabus, J. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl fuer Wasserguete- und Abfallwirtschaft; Urban, A.I.; Friedel, M. [Kassel Univ. (Gesamthochschule) (Germany). Fachgebiet Abfalltechnik

    1998-09-01

    One of the main disposal paths for sewage sludge in the past was landfilling. This option was severely restricted by the issue of the Technical Code on Household Waste in 1993. In its agricultural applications sewage sludge serves as a fertiliser and a soil improvement agent. Estimates on potential thermal treatment capacities have shown that there are enough public power plants to accommodate and provide thermal treatment for the total of sewage sludge arisings in Germany. As can be seen from the estimates presented in this paper, it would not even be necessary to restrict oneself to public power plant capacities. The paper points out possibilities of using plant capacities already existing in industrial firing plants and certain production sectors. It uses a comparison to show that sewage sludge would have to be dried in order to permit its thermal treatment in these private facilities. Aside from this, there are a number of new techniques entering the market which from the technical viewpoint also appear to be well suited for thermal sewage sludge treatment. [Deutsch] Ein wesentlicher Entsorgungsweg von Klaerschlamm war in der Vergangenheit die Verbringung auf eine Deponie. Diese Moeglichkeit ist durch die TA Siedlungsabfall von 1993 stark eingeschraenkt. Bei der landwirtschaftlichen Verwertung wird durch den Klaerschlamm eine Duengewirkung sowie eine Bodenverbesserung erreicht. Eine Abschaetzung der potentiellen thermischen Behandlungskapazitaeten zeigt, dass die gesamte bundesdeutsche Klaerschlammenge in oeffentlichen Kraftwerken unterzubringen und thermisch zu behandeln waere. Wie die hier dargestellten Abschaetzungen gezeigt haben, ist man durchaus nicht allein auf die Nutzung oeffentlicher Kraftwerkskapazitaeten angewiesen. Es wurden Moeglichkeiten zur Nutzung vorhandener Anlagenkapazitaeten in industriellen Feuerungsanlagen und in Produktionsbereichen aufgezeigt. Wie aus einem Vergleich erkennbar wird, ist allerdings eine Trocknung der Klaerschlaemme

  7. Radiation disinfection of liquid sewage sludge for safe reutilization

    International Nuclear Information System (INIS)

    Harsoyo; Hilmy, Nazly; Suwirma, S.

    1992-01-01

    Liquid sewage sludge with water content of 80.9% was irradiated with doses of 2, 4, and 6 kGy respectively and then stored at room temperature. Parameter observed were total microbes per g, chemical, physical properties. Total bacterial counts of unirradiated liquid sewage sludge were found to be 12,91 X 10(5) per g, while coliform, enterobacteriaceae, staphylococcus, fecal streptococcus, and pseudomonas were found to be 76.66 X 10(4) per g, 23.82 X 10(4) per g, 46.57 X 10(3) per g, 6.27 X 10(2) per g, 20.04 X 10(3) per g, respectively. About 10% of the total coliform were escherichia coli. Irradiation dose of 4 kGy eliminated salmonella from all samples observed. No shigella was found in the samples. Total nitrogen contents of the liquid sewage sludge ranged berween 0.34 and 0.48%, phosphorus between 0.78 and 1.04%, and potassium between 0.04 and 0.06%. Heavy metal elements were found only in very small amount. The BOD(5), COD, solid suspension, particle size, and sedimentation rate of unirradiated liquid sewage sludge were found to be 1.49 ppm, 13.93% W, 46 mg/ml, 0.0035 ml, and 11.30 cm/week, respectively. A combination of irradiation at 4 kGy and storage for 4 weeks could eliminate enterobacteriaceae, staphylococcus, fecal streptococcus, psedomonas, and salmonella in the liquid sewage sludge. (authors). 9 refs, 13 tabs

  8. phytoremediation of sewage sludge in soils contaminated

    African Journals Online (AJOL)

    PROF EKWUEME

    repeated increase daily or weekly application of sewage ... fertilizers, herbicides, germicides and decomposition and burning of fossil fuels. ... However, organic and inorganic pollutants greatly ... green vegetables for the in-situ or ex-situ.

  9. Earthworms facilitate the stabilization of pelletized dewatered sludge through shaping microbial biomass and activity and community.

    Science.gov (United States)

    Fu, Xiaoyong; Cui, Guangyu; Huang, Kui; Chen, Xuemin; Li, Fusheng; Zhang, Xiaoyu; Li, Fei

    2016-03-01

    In this study, the effect of earthworms on microbial features during vermicomposting of pelletized dewatered sludge (PDS) was investigated through comparing two degradation systems with and without earthworm E isenia fetida involvement. After 60 days of experimentation, a relatively stable product with low organic matter and high nitrate and phosphorous was harvested when the earthworms were involved. During the process, earthworms could enhance microbial activity and biomass at the initial stage and thus accelerating the rapid decomposition of PDS. The end products of vermicomposting allowed the lower values of bacterial and eukaryotic densities comparison with those of no earthworm addition. In addition, the presence of earthworms modified the bacterial and fungal diversity, making the disappearances of some pathogens and specific decomposing bacteria of recalcitrant substrates in the vermicomposting process. This study evidences that earthworms can facilitate the stabilization of PDS through modifying microbial activity and number and community during vermicomposting.

  10. Evaluation of sewage sludge and slow pyrolyzed sewage sludge-derived biochar for adsorption of phenanthrene and pyrene.

    Science.gov (United States)

    Zielińska, Anna; Oleszczuk, Patryk

    2015-09-01

    The present study investigated the sorption of phenanthrene (PHE) and pyrene (PYR) by sewage sludges and sewage sludge-derived biochars. The organic carbon normalized distribution coefficient (log K(OC) for C(w) = 0.01 S(w)) for the sewage sludges ranged from 5.62 L kg(-1) to 5.64 L kg(-1) for PHE and from 5.72 L kg(-1) to 5.75 L kg(-1) for PYR. The conversion of sewage sludges into biochar significantly increased their sorption capacity. The value of log K(OC) for the biochars ranged from 5.54 L kg(-1) to 6.23 L kg(-1) for PHE and from 5.95 L kg(-1) to 6.52 L kg(-1) for PYR depending on temperature of pyrolysis. The dominant process was monolayer adsorption in the micropores and/or multilayer surface adsorption (in the mesopores), which was indicated by the significant correlations between log K(OC) and surface properties of biochars. PYR was sorbed better on the tested materials than PHE. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Hydrothermal treatment coupled with mechanical expression at increased temperature for excess sludge dewatering: the dewatering performance and the characteristics of products.

    Science.gov (United States)

    Wang, Liping; Li, Aimin

    2015-01-01

    Hydrothermal treatment coupled with mechanical expression at increased temperature in two separate cells respectively is effective for the dewatering of excess sludge with low energy consumption. The objectives of this study were to evaluate the dewatering performance and the characteristics of obtained products (hydrothermal sludge, hydrochar and filtrate). The results showed that harsher hydrothermal treatment (temperature from 120 to 210 °C and residence time from 10 to 90 min) led to greater water removal (from 7.44 to 96.64% reduction of total water) and mechanical pressure became less significant as it increased. The whole expression stage was completely described by the modified Terzaghi-Voigt rheological model. The role of tertiary consolidation stage in the water removal was reduced with hydrothermal treatment being stronger. The hydrothermal treatment is mainly a devolatilization process. The observed changes in H/C and O/C for hydrothermal sludge suggested dehydration was the major reaction mechanism and decarboxylation only occurred significantly at higher temperature. The higher heating value correlated well with carbon content of sludge, which was increased by 4.8% for hydrothermal sludge at 210 °C for 60 min and significantly decreased by 15.4% for hydrochar after 6.0 MPa for 20 min. The solubilization and decomposition of proteins, polysaccharides and DNA were determined to be temperature and residence time dependent. The improvement of dewaterability was closely correlated to the variation of these biopolymers. The filtrates collected above 150 °C were found to be acidic. The increase of humic substances and the melanoidins formed by Maillard reaction were largely responsible for the filtrate color.

  12. Properties of fired clay brick incorporating with sewage sludge waste

    Science.gov (United States)

    Kadir, Aeslina Abdul; Salim, Nurul Salhana Abdul; Sarani, Noor Amira; Rahmat, Nur Aqma Izurin; Abdullah, Mohd Mustafa Al Bakri

    2017-09-01

    The production of sludge in wastewater treatment plant is about to increase every year and most of the sludge was directly disposed to landfill. In addition, the constraint to treat sludge is very high in cost and time- consuming could be disadvantages to the responsible parties. Therefore, this research was conducted to utilize sludge produced from the wastewater treatment plant into fired clay brick as one of the alternatives of disposal method. In this study, the research attempt to incorporate sewage sludge waste (SSW) into fired clay brick. The sewage sludge brick (SSB) mixtures were incorporated with 0%, 1%, 5%, 10%, and 20% of SSW. The manufactured bricks were fired at 1050°C with heating rate of 1°C/min. Physical and mechanical properties test were conducted such as shrinkage, density, water absorption and compressive strength. As the conclusion, brick with utilization 5% of SSW is acceptable to produce good quality of brick. This study shows by using SSW in fired clay brick could be an alternative method to dispose of the SSW and also could act as a replacement material for brick manufacturing with appropriate mix and design.

  13. Radioactive nuclides in sewage sludges and problems associated with their utilisation or dumping

    International Nuclear Information System (INIS)

    Schneider, P.; Brunner, P.; Tiefenbrunner, F.; Dierich, M.P.

    1990-01-01

    In a sewage plant with radioactively contaminated sewage an accumulation of radionuclides was found in the sewage sludge. The specific activities are in inverse proportion to the water content of the sewage sludge, the dehydrated sewage sludge having the highest specific activities. The retained radionuclides seem to be firmly accumulated in the sludge. Nevertheless, they are in a form which can be utilised by plants. This was demonstrated in experiments with Trifolium Repens and Secale Cereale where the rate of absorption was 15-33% (in Ci/kg dry weight per plant: nCi/kg dry weight soil x 100). Thus there are problems associated with using radioactively contaminated sewage sludge as a fertiliser. In further experiments to extract radioactive nuclides from ashed sewage sludge it was shown that acidifying the aqueous phase results in an increase in the level of radioactivity in the eluated fractions. (author)

  14. Analysis of sewage sludge and cover soil by neutron activation analysis

    International Nuclear Information System (INIS)

    Moon, J.H.; Lim, J.M.; Kim, S.H.; Chung, Y.S.

    2008-01-01

    The Korean government reported that in 2005, 4395 tons/day of sewage sludge were generated from sewage disposal facilities in Korea and only 11.03% of it was reused. In addition, as a direct landfill of sewage sludge was forbidden from June 2003, research for a relevant disposal technique has been increasing. In this study, the aims were to analyze the collected sewage sludge samples and to evaluate the possibility for their reuse by a comparison of the elemental contents from a sewage sludge and a cover soil. Sludge samples were collected from a sewage disposal plant in Daejeon city and the cover soil was produced by a dilution of a sewage sludge with quicklime. Instrumental neutron activation analysis was employed to determine the elemental contents in the samples. Twenty seven elements were analyzed and their concentrations were compared. (author)

  15. Leaching of Heavy Metals Using SPLP Method from Fired Clay Brick Incorporating with Sewage Sludge

    Science.gov (United States)

    Kadir, Aeslina Abdul; Salim, Nurul Salhana Abdul; Amira Sarani, Noor; Aqma Izurin Rahmat, Nur

    2017-05-01

    Sewage sludge is a by-product generate from wastewater treatment process. The sewage sludge contains significant trace metal such as Cr, Mn, Ni, Cu, Zn, As, Cd and Pb which are toxic to the environment. Sewage sludge is disposed of by landfilling method. However, this option not suitable because of land restriction and environmental control regulations imposed. Therefore, sewage sludge from wastewater treatment plant was incorporated into fired clay brick to produce good quality of brick as well as reducing heavy metals from sludge itself. Sewage sludge with 0%, 1%, 5%, 10% and 20% of were incorporated into fired clay bricks and fired at 1050°C temperature with heating rates of 1°C/min. The brick sample then crushed and sieved through 9.5 mm sieve for Synthetic Precipitation Leaching Procedure (SPLP). From the results, incorporation up to 20% of sewage sludge has leached less heavy metals and compliance with USEPA standard.

  16. Feasibility of vermicomposting dewatered sludge from paper mills using Perionyx excavatus

    Directory of Open Access Journals (Sweden)

    Puspanjali Sonowal

    2013-06-01

    Full Text Available India has a large network of pulp and paper mills of varying capacity. On an industrial scale the sludge from paper and pulp mills is disposed of either as landfill or incinerated. Both methods result in the loss of a valuable resource and have obvious environmental and economic disadvantages. The solid waste from pulp and paper mills is a source of organic matter and its proper disposal and management is the responsibility of the industry. As composting/vermicomposting could be used to transform this waste trials were carried out to determine the feasibility of converting dewatered sludge (DS into a value added end product using an earthworm, Perionyx excavatus. The vermicomposting of the waste resulted in an increase in its electrical conductivity (EC, ash content, total nitrogen (TN, total phosphorous (TP and available phosphorous (AP, respectively, and a decrease in total organic carbon (TOC, biochemical oxygen demand (BOD, chemical oxygen demand (COD, oxygen uptake rate (OUR and evolution of carbon dioxide (CO2. Overall, the best treatment was T5 in which there was a 76.1% increase in TP, 58.7% in TN, 74.5% decrease in TOC , and a reduction of 6.7 fold in the production of CO2 and 10.7 fold in BOD, respectively. Our trials demonstrate that vermicomposting using an epigeic earthworm, Perionyx excavatus, is an alternate and environmentally safe way of recycling paper mill sludge if it is mixed with an appropriate amount of cow dung and food processing waste. Overall T5 was the best combination of paper mill sludge and waste for vermicomposting followed by T3, T2, T4 and T1, respectively.

  17. Inactivation of bacteria in sewage sludge by gamma radiation

    International Nuclear Information System (INIS)

    Pandya, G.A.; Kapila, Smita; Kelkar, V.B.; Negi, Shobha; Modi, V.V.

    1987-01-01

    The survival of certain bacterial cultures suspended in sewage sludge and exposed to gamma-radiation was studied. The inactivation patterns of most of the organisms were significantly different when irradiation was performed using sewage samples collected in the summer and monsoon seasons. The summer sample collected from the anaerobic digester afforded significant protection to both Gram negative and Gram positive organisms. This was evident by the increase in dose required to bring about a 6 log cycle reduction in viable count of the bacterial cultures, when suspended in sewage samples instead of phosphate buffer. The observations made using monsoon digester samples were quite different. This sewage sludge greatly enhanced inactivation by gamma-radiation in most cases. The effects of certain chemicals on the inactivation patterns of two organisms - Salmonella typhi and Shigella flexneri - were examined. Arsenate, mercury and lead salts sensitised S. typhi, while barium acetate and sodium sulphide protected this culture against gamma-radiation. In the case of Sh. flexneri, barium acetate and iodacetamide proved to be radioprotectors. The effects of some chemicals on the inactivation pattern of Sh. flexneri cells irradiated in sludge are also discussed. (author)

  18. Impact of composting strategies on the degradation of nonylphenol in sewage sludge.

    Science.gov (United States)

    Zheng, Guodi; Chen, Tongbin; Yu, Jie; Gao, Ding; Shen, Yujun; Niu, Mingjie; Liu, Hongtao

    2015-12-01

    Nonylphenol can be present in sewage sludge, and this can limit the use of the sewage sludge to amend soil. Composting is one of the most efficient and economical methods of making sewage sludge stable and harmless. The nonylphenol degradation rates during composting with added bulking agents and with aeration applied were studied. Three organic bulking agents (sawdust, corn stalk, and mushroom residue) were added to sewage sludge, and the effects of the bulking agents used and the amount added on nonylphenol degradation were determined. The highest apparent nonylphenol degradation rate (71.6%) was found for sewage sludge containing 20% mushroom residue. The lowest apparent nonylphenol degradation rate (22.5%) was found for sewage sludge containing 20% sawdust. The temperature of the composting pile of sewage sludge containing 20% sawdust became too high for nonylphenol to be efficiently degraded, and the apparent nonylphenol degradation rate was lower than was found for sewage sludge containing 10% sawdust. Increasing the ventilating time from 5 to 15 min increased the apparent nonylphenol degradation rate from 19.7 to 41.6%. Using appropriate aerobic conditions facilitates the degradation of nonylphenol in sewage sludge, decreasing the risks posed by sewage sludge applied to land. Adding too much of a bulking agent can decrease the amount of the nonylphenol degraded. Increasing the ventilating time and the amount of air supplied can increase the amount of nonylphenol degraded even if doing so causes the composting pile temperature to remain low.

  19. Biodegradation of tetrabromobisphenol A in the sewage sludge process.

    Science.gov (United States)

    Peng, Xingxing; Wang, Zhangna; Wei, Dongyang; Huang, Qiyuan; Jia, Xiaoshan

    2017-11-01

    Anaerobic sewage sludge capable of rapidly degrading tetrabromobisphenol A (TBBPA) was successfully acclimated in an anaerobic reactor over 280days. During the period from 0 to 280days, the TBBPA degradation rate (DR), utilization of glucose, and VSS were monitored continuously. After 280days of acclimation, the TBBPA DR of active sludge reached 96.0% after 20days of treatment in batch experiments. Based on scanning electron microscopy (SEM) observations and denaturing gradient gel electrophoresis (DGGE) determinations, the diversity of the microorganisms after 0 and 280days in the acclimated anaerobic sewage sludge was compared. Furthermore, eleven metabolites, including 2-bromophenol, 3-bromophenol, 2,4-dibromophenol, 2,6-dibromophenol, tribromophenol and bisphenol A, were identified by gas chromatography-mass spectrometry (GC-MS). Moreover, the six primary intermediary metabolites were also well-degraded by the acclimated anaerobic sewage sludge to varying degrees. Among the six target metabolites, tribromophenol was the most preferred substrate for biodegradation via debromination. These metabolites degraded more rapidly than monobromide and bisphenol A. The biodegradation data of the intermediary metabolites exhibited a good fit to a pseudo-first-order model. Finally, based on the metabolites, metabolic pathways were proposed. In conclusion, the acclimated microbial consortia degraded TBBPA and its metabolites well under anaerobic conditions. Copyright © 2017. Published by Elsevier B.V.

  20. Mechanisms and kinetics of granulated sewage sludge combustion.

    Science.gov (United States)

    Kijo-Kleczkowska, Agnieszka; Środa, Katarzyna; Kosowska-Golachowska, Monika; Musiał, Tomasz; Wolski, Krzysztof

    2015-12-01

    This paper investigates sewage sludge disposal methods with particular emphasis on combustion as the priority disposal method. Sewage sludge incineration is an attractive option because it minimizes odour, significantly reduces the volume of the starting material and thermally destroys organic and toxic components of the off pads. Additionally, it is possible that ashes could be used. Currently, as many as 11 plants use sewage sludge as fuel in Poland; thus, this technology must be further developed in Poland while considering the benefits of co-combustion with other fuels. This paper presents the results of experimental studies aimed at determining the mechanisms (defining the fuel combustion region by studying the effects of process parameters, including the size of the fuel sample, temperature in the combustion chamber and air velocity, on combustion) and kinetics (measurement of fuel temperature and mass changes) of fuel combustion in an air stream under different thermal conditions and flow rates. The combustion of the sludge samples during air flow between temperatures of 800 and 900°C is a kinetic-diffusion process. This process determines the sample size, temperature of its environment, and air velocity. The adopted process parameters, the time and ignition temperature of the fuel by volatiles, combustion time of the volatiles, time to reach the maximum temperature of the fuel surface, maximum temperature of the fuel surface, char combustion time, and the total process time, had significant impacts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. 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)

  2. Effects of ultrasonic disintegration of excess sewage sludge.

    Science.gov (United States)

    Zielewicz, Ewa

    2016-10-01

    Breaking down sludge floc (sonodyspergation effect) and destruction of the cell membranes of microorganisms forming floc is a direct effect of ultrasonic disintegration of sludge excess. This results in release of organic material by liquid sludge (the sonolysis effect). Desired technological effects of the disintegration are: to shorten the hydrolytic phase of fermentation, to increase the production of biogas (source of renewable energy) and an increased mineralization (stability) of fermented sludge. The presented study demonstrates research covering thickened excess sludge of various physicochemical properties, collected from nine municipal sewage treatment plants. The sludge was subjected to ultrasonic disintegration using three differently constructed disintegrators and different proportions of sonification area. Direct effects of disintegration were monitored and recorded using selected indicators describing changes in the properties of sludge and increase of substance dispersed and dissolved in the supernatant liquid to be filtered. Studies have demonstrated that those (direct) effects of ultrasonic disintegration depend on the physicochemical properties of the sludge (foremost the concentration of dry solids) that determine their variable susceptibility to the disintegration methods. The direct effects also depend on optimal process conditions (which consist of the construction of the ultrasonic disintegrator), the geometric proportions of the sonication area and the operating parameters of disintegration (which could be appropriately matched to the characteristics of sludge). The most preferable results were obtained for ultrasonic disintegration of sludge with a dry matter concentration C 0 < 4.2 %. The highest effect of sonolysis-an almost 30-fold increase in the COD dissolved in the supernatant-was obtained for the sludge of lowest dry matter (C 0 = 2.0 %), which was sonicated in a reactor with a short transducer of the largest radiating surface

  3. 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)

  4. Mechanism of red mud combined with Fenton's reagent in sewage sludge conditioning.

    Science.gov (United States)

    Zhang, Hao; Yang, Jiakuan; Yu, Wenbo; Luo, Sen; Peng, Li; Shen, Xingxing; Shi, Yafei; Zhang, Shinan; Song, Jian; Ye, Nan; Li, Ye; Yang, Changzhu; Liang, Sha

    2014-08-01

    Red mud was evaluated as an alternative skeleton builder combined with Fenton's reagent in sewage sludge conditioning. The results show that red mud combined with Fenton's reagent showed good conditioning capability with the pH of the filtrate close to neutrality, indicating that red mud acted as a neutralizer as well as a skeleton builder when jointly used with Fenton's reagent. Through response surface methodology (RSM), the optimal dosages of Fe(2+), H2O2 and red mud were proposed as 31.9, 33.7 and 275.1 mg/g DS (dry solids), respectively. The mechanism of the composite conditioner could be illuminated as follows: (1) extracellular polymeric substances (EPS), including loosely bound EPS and tightly bound EPS, were degraded into dissolved organics, e.g., proteins and polysaccharides; (2) bound water was released and converted into free water due to the degradation of EPS; and (3) morphology of the conditioned sludge exhibited a porous structure in contrast with the compact structure of raw sludge, and the addition of red mud formed new mineral phases and a rigid lattice structure in sludge, allowing the outflow of free water. Thus, sludge dewatering performance was effectively improved. The economic assessment for a wastewater treatment plant of 370,000 equivalent inhabitants confirms that using red mud conditioning, combined with Fenton's reagent, leads to a saving of approximately 411,000 USD/y or 50.8 USD/t DS comparing with using lime and ordinary Portland cement combined with Fenton's reagent, and approximately 612,000 USD/y or 75.5 USD/t DS comparing with the traditional treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. 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

    Thermal drying of sewage sludge implies sanitation and improves practical handling options of the sludge prior to land application. However, it may also affect its value as a fertilizer. The objective of this study was to assess whether thermal drying of sewage sludge, as well as drying temperature...

  6. The disc method. A new method for selecting facilitations in flocculating sludge to be dewatered in centrifuges; Metodo de disco. Un nuevo metodo para la seleccion de floculantes en la floculacion de lodos a deshidratar en centrifugas

    Energy Technology Data Exchange (ETDEWEB)

    Canga Rodriguez, J.; Gutierrez Lavin, A.

    2002-07-01

    An experimental protocol was designed at a laboratory scale, in view of achieving the selection with different poly electrolytes related to the chemical conditioning (flocculation) of sewage sludge before dewatering it in a drying centrifuge. The method is based on a new parameter of quality of the formed floc, which measures its compaction when is submitted to a fix external strength. Some experimental tests have been introduced, whose results are numbers, avoiding all subjective aspects related to direct observation of flocs. (Author) 8 refs.

  7. Application of Fuzzy Synthetic Evaluation in Selection of Best Sludge Dewatering Option in Ghods Town WWTP in Tehran

    Directory of Open Access Journals (Sweden)

    Masoud Taheriyoun

    2015-03-01

    Full Text Available The design and upgrade of sludge treatment systems generally depend on the decision made regarding the appropriate system from among the options available. The selection process has become increasingly important and complex due to recent technological developments that have led to increased diversity in the available options which offer a wide variety of capabilities. The multi-criteria decision making method is one of the techniques recently developed which takes into account all the criteria involved in the decision making process. The Ghods Town WWTP in the west of Tehran located in the vicinity of residential areas has given rise to claims by citizens due to the odors emitted by the sludge sand drying bed, which justifies the replacement of the present sludge dewatering system. For this purpose, the multi-criteria decision making method based on the fuzzy synthetic evaluation method was used to identify the optimal sludge dewatering system appropriate for the WWTP under consideration. Furthermore, weighting of the subjective (social, environmental, and administrative criteria was accomplished using the analytical hierarchy process and the objective (i.e., economic criteria were weighted using the entropy concept. In this method, the triangular fuzzy membership function was also used to take into account the uncertainty associated with each of the decision making parameters. Based on the results obtained, the belt filter press dewatering system and the filter press were identified as the preferred solutions.

  8. Evaluation of the nitrogen load of the sludge liquor from the band filters of the sewage treatment plant of Pinedo (Valencia); Nitrogeno aportado por el licor del fango de los filtros banda a la linea de retorno en la EDAR de Pinedo (Valencia)

    Energy Technology Data Exchange (ETDEWEB)

    Bes Pia, A.; Mendoza Roca, J. A. [Universidad Politecnica de Valencia (Spain)

    2000-07-01

    The sludge treatment in a sewage treatment plant generates liquid effluents called sludge liquors that are pumped to the plant entrance. These effluents provide a pollution load that must be considered in the design of the sewage treatment plant, outstanding, all and above the nitrogen load produced by the sludge dewatering after its anaerobic digestion. In the present research the mentioned liquor is studied and characterized in order to determine the nitrogen load recirculated to the entrance of the old-established line of the Pinedo sewage treatment plant (Valencia). (Author) 3 refs.

  9. Sanitary effect of gamma irradiation on sewage sludge

    International Nuclear Information System (INIS)

    Hess, E.; Breer, C.

    1975-01-01

    Our investigations prove that sludge contains Salmonellae in more than 90% of samples. The maximum number of organisms was 10 7 per litre. One of our most important findings was the fact that neither aerobic stabilization nor anaerobic digestion significantly reduces contamination with Salmonellae. Moreover we found that Salmonellae in sewage sludge spread on grass may survive up to 72 weeks. Fertilizing with unsanitized sludge may therefore lead to transmission from plant to animal. The increasing number of Salmonella carriers among our herds of cattle and their striking accumulation during the grazing period demonstrate that such transmission represents a growing danger. Sanitation of sludge to be used as fertilizer is therefore urgent. In our investigation of the sanitary effect of pasteurization (70degC for 30 min) and of gamma irradiation on sewage sludge, we examined the number of Enterobacteriaceae before and after irradiation in 259 specimens of sludge from 44 different sewage disposal plants. The doses applied were 100, 200, 300, 400 and also 500 krad. We found a linear reduction of Enterobacteriaceae with increasing doses; a dose of 300 krad resulted in a death rate of 10 4 - 10 8 , occasionally 10 9 Enterobacteriaceae; and there were less than 10 Enterobacteriaceae per gram in 97.2% of the samples irradiated with 300 krad. The results of these model experiments could be completely confirmed under practical conditions in the irradiation plant of Geiselbullach. The sanitary effect of gamma irradiation with 300-350 krad, determined by the reduction in Enterobacteriaceae, was equivalent to the effect of heat treatment by pasteurization. (author)

  10. Potential priority pollutants in sewage sludge

    DEFF Research Database (Denmark)

    Eriksson, Eva; Christensen, Nina; Schmidt, Jens Ejbye

    2008-01-01

    compounds using their inherent properties and environmental fate it was shown that 99 XOCs could be classified as being hazardous with regard to the solid phase and 23 were found to be priority pollutants in the subsequent hazard assessment. The final selected priority pollutants can act as indicators when...... assessing sludge quality. They were compared with European legislations and discussed in regard for pointing out the need for mitigation such as substitution. Furthermore, the potential need for implementation of sludge treatment trains in order to meet the society's needs was addressed....

  11. Radiation technology for sewage sludge treatment: The Argentine project

    International Nuclear Information System (INIS)

    Graino, J.G.

    2001-01-01

    Within the environmental applications of ionizing radiation, disinfection of wastewaters or sewage sludges is one of the most best known. Argentina based the project of a full scale irradiation plant on the gamma irradiation application, utilizing Argentine made Cobalt-60 sources. The design characteristics, process descriptions and costs are included. The research project developed information about the irradiation effects on the sludges with respect to plant performance. For the purpose of oxi-irradiation experiments, a lab-scale pool irradiator was constructed and is described. (author)

  12. Costs and hygienic necessity of sewage sludge pasteurization in Switzerland

    International Nuclear Information System (INIS)

    Obrist, W.

    1975-01-01

    Cost analyses of sludge pasteurization by heat treatment were made in six Swiss sewage treatment plants during 1973. Data indicate that specific cost figures will be between S.Fr.3.- and 14.- per cubic metre, depending mainly on capacity and actual output of the plant. The risk of infection for man and animals is a controversial question. Public health experts deny hazards from agricultural utilization of unpasteurized digested sludges, whereas veterinary hygienists stress the potential dangers for animals and man. A practicable pragmatic approach is suggested until sufficient evidence is available. Energy, ecological and economic aspects must be taken into consideration. (Author)

  13. Effects of sewage sludge fertilizer on heavy metal accumulation and consequent responses of sunflower (Helianthus annuus).

    Science.gov (United States)

    Belhaj, Dalel; Elloumi, Nada; Jerbi, Bouthaina; Zouari, Mohamed; Abdallah, Ferjani Ben; Ayadi, Habib; Kallel, Monem

    2016-10-01

    Use of sewage sludge, a biological residue produced from sewage treatment processes in agriculture, is an alternative disposal technique of waste. To study the usefulness of sewage sludge amendment for Helianthus annuus, a pot experiment was conducted by mixing sewage sludge at 2.5, 5, and 7.5 % (w/w) amendment ratios to the agricultural soil. Soil pH decreased whereas electrical conductivity, organic matter, total N, available P, and exchangeable Na, K, and Ca increased in soil amended with sewage sludge in comparison to unamended soil. Sewage sludge amendment led to significant increase in Pb, Ni, Cu, Cr, and Zn concentrations of soil. The increased concentration of heavy metals in soil due to sewage sludge amendment led to increases in shoot and root concentrations of Cr, Cu, Ni, and Zn in plant as compared to those grown on unamended soil. Accumulation was more in roots than shoots for most of the heavy metals. Moreover, high metal removal for the harvestable parts of the crops was recorded. Sewage sludge amendment increased root and shoot length, leaves number, biomass, and antioxidant activities of sunflower. Significant increases in the activities of antioxidant enzymes and in the glutathione, proline, and soluble sugar content in response to amendment with sewage sludge may be defense mechanisms induced in response to heavy metal stress. Graphical abstract Origin, fate and behavior of sewage sludge fertilizer.

  14. Energetic assessment of air-steam gasification of sewage sludge and of the integration of sewage sludge pyrolysis and air-steam gasification of char

    International Nuclear Information System (INIS)

    Gil-Lalaguna, N.; Sánchez, J.L.; Murillo, M.B.; Atienza-Martínez, M.; Gea, G.

    2014-01-01

    Thermo-chemical treatment of sewage sludge is an interesting option for recovering energy and/or valuable products from this waste. This work presents an energetic assessment of pyrolysis and gasification of sewage sludge, also considering the prior sewage sludge thermal drying and the gasification of the char derived from the pyrolysis stage. Experimental data obtained from pyrolysis of sewage sludge, gasification of sewage sludge and gasification of char (all of these performed in a lab-scale fluidized reactor) were used for the energetic calculations. The results show that the energy contained in the product gases from pyrolysis and char gasification is not enough to cover the high energy consumption for thermal drying of sewage sludge. Additional energy could be obtained from the calorific value of the pyrolysis liquid, but some of its properties must be improved facing towards its use as fuel. On the other hand, the energy contained in the product gas of sewage sludge gasification is enough to cover the energy demand for both the sewage sludge thermal drying and the gasification process itself. Furthermore, a theoretical study included in this work shows that the gasification efficiency is improved when the chemical equilibrium is reached in the process. - Highlights: • 4 MJ kg −1 for thermal drying of sewage sludge (SS) from 65 to 6.5 wt.% of moisture. • 0.15 MJ kg −1 for thermal decomposition of sewage sludge during fast pyrolysis. • Not enough energy in gases from SS pyrolysis and char gasification for thermal drying. • Enough energy in SS gasification gas for thermal drying and gasification process. • Gasification efficiency improves when equilibrium is reached in the process

  15. Soil cadmium mobility as a consequence of sewage sludge disposal

    Energy Technology Data Exchange (ETDEWEB)

    Lamy, I. [Station de Science du Sol, Versailles (France); Bourgeois, S.; Bermond, A. [Institut National Agronomique, Paris (France)

    1993-10-01

    Anaerobically digested liquid sewage sludge was applied as a single treatment to a loamy hydromorphic drained soil, characteristic of agricultural soils in the North of France, at a rate of 11 Mg of dry solids ha{sup -1}. Total Cd concentrations of drainage waters for both amended and unamended plots were monitored at selected times to follow the mobility of Cd after sludge disposal. The drained ground-water of the plot that exhibited the highest discharge of sludge soluble organic matter (SSOM) exhibited about twice the Cd levels of the control plot during the first few weeks following sludge disposal (average of 3 and 1.5 {mu}g L{sup -1} respectively). Laboratory experiments were conducted to provide estimates of the relative binding strength of Cd-soil interactions as well as Cd-SSOM interactions. The behavior of Cd in a mixed sludge-soil system showed that the addition of sludge soluble organic matter to the soil led to a decrease in the sorption of this cation across the pH range between 5 and 7. The laboratory studies highlighted the role of soluble organic matter in soil Cd speciation, and can be used to speculate on the perturbations induced by high levels of sludge soluble organic matter introduced into a soil.

  16. Metal fractionation in sludge from sewage UASB treatment.

    Science.gov (United States)

    Braga, A F M; Zaiat, M; Silva, G H R; Fermoso, F G

    2017-05-15

    This study evaluates the trace metal composition and fractionation in sludge samples from anaerobic sewage treatment plants from six cities in Brazil. Ten metals were evaluated: Ni, Mn, Se, Co, Fe, Zn, K, Cu, Pb and Cr. Specific methanogenic activity of the sludge was also evaluated using acetic acid as the substrate. Among the essential trace metals for anaerobic digestion, Se, Zn, Ni and Fe were found at a high percentage in the organic matter/sulfide fraction in all sludge samples analyzed. These metals are less available for microorganisms than other metals, i.e., Co and K, which were present in significant amounts in the exchangeable and carbonate fractions. Cu is not typically reported as an essential metal but as a possible inhibitor. One of the samples showed a total Cu concentration close to the maximal amount allowed for reuse as fertilizer. Among the non-essential trace metals, Pb was present in all sludge samples at similar low concentrations and was primarily present in the residual fraction, demonstrating very low availability. Cr was found at low concentrations in all sludge samples, except for the sludge from STP5; interestingly, this sludge presented the lowest specific methanogenic activity, indicating possible Cr toxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. 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.

  18. Sewage sludge utilisation and disposal in Switzerland; Loesungen zur Verwertung oder Beseitigung von Klaerschlamm in der Schweiz

    Energy Technology Data Exchange (ETDEWEB)

    Matter, C. [TBF Toscano-Bernardi-Frey AG, Zuerich (Switzerland); Pelloni, L.; Vollmeier, T. [TBF Toscano-Bernardi-Frey AG, Zuerich (Switzerland)

    1996-11-01

    Sewage sludge can be dumped in Switzerland only during a period of transition which will end by 2000. The amount of sewage sludge utilized in agriculture is limited. For these reasons, sewage sludge combustion is an important option. The available methods for sludge combustion are described and compared.

  19. Use of sewage sludge - nitrogen availability and heavy metal uptake into rape

    International Nuclear Information System (INIS)

    Gerzabek, M. H.; Lombi, E.; Herger, P.

    1998-07-01

    The results of a three years experiment with large pots in the field evaluating the effects of sewage sludge (sterilised by γ-irradiation or not sterilised) on rape growth, heavy metal-and N-uptake, using the 15 N-dilution technique, are presented. Mobile fractions of Cd, Cu and Zn increased significantly in the substrate due to sewage sludge treatments. However heavy metal transfer into rape plants did not respond clearly. Rape growth was clearly enhanced in the first and third year due to sewage sludge applications. The average N-utilization by rape from sewage sludge in a three years period decreased from 7.4 % (first year), 1.8 % (second year) to 1.1 % (third year), resulting in an overall utilization of 10.3 % of sewage sludge - N t by rape plants. Irradiation of sewage sludge did not result in any significant effect on the investigated parameters. (author)

  20. Sewage sludge pyrolysis - the distribution of heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Kistler, R.; Widmer, F.; Brunner, P.

    1986-01-01

    The paper informs about the heavy metal contents of sewage sludges and discusses the origin of household, industry and surface sewerage of the respective heavy metals. The study aimed at assessing whether and in how far heavy metal volatility may be checked by reducing the temperature during sewage sludge pyrolysis. The testing equipment used was made of glass/silica glass. Instead of in particles heavy metals were precipitated in the gaseous state. Except from mercury heavy metals are retained by the ashes up to temperatures from 450 to 555/sup 0/C. Due to the persistence of mercury care should be taken to keep the sewerage clear of it from the very beginning. Emissions caused by reactor materials can be avoided by choosing appropriate pyrolysis reactors.

  1. 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.

  2. Comparative study of the methods used for treatment and final disposal of sewage sludge in European countries.

    Science.gov (United States)

    Kelessidis, Alexandros; Stasinakis, Athanasios S

    2012-06-01

    Municipal wastewater treatment results to the production of large quantities of sewage sludge, which requires proper and environmentally accepted management before final disposal. In European Union, sludge management remains an open and challenging issue for the Member States as the relative European legislation is fragmentary and quite old, while the published data concerning sludge treatment and disposal in different European countries are often incomplete and inhomogeneous. The main objective of the current study was to outline the current situation and discuss future perspectives for sludge treatment and disposal in EU countries. According to the results, specific sludge production is differentiated significantly between European countries, ranging from 0.1 kg per population equivalent (p.e.) and year (Malta) to 30.8 kg per p.e. and year (Austria). More stringent legislations comparing to European Directive 86/278/EC have been adopted for sludge disposal in soil by several European countries, setting lower limit values for heavy metals as well as limit values for pathogens and organic micropollutants. A great variety of sludge treatment technologies are used in EU countries, while differences are observed between Member States. Anaerobic and aerobic digestion seems to be the most popular stabilization methods, applying in 24 and 20 countries, respectively. Mechanical sludge dewatering is preferred comparing to the use of drying beds, while thermal drying is mainly applied in EU-15 countries (old Member States) and especially in Germany, Italy, France and UK. Regarding sludge final disposal, sludge reuse (including direct agricultural application and composting) seems to be the predominant choice for sludge management in EU-15 (53% of produced sludge), following by incineration (21% of produced sludge). On the other hand, the most common disposal method in EU-12 countries (new Member States that joined EU after 2004) is still landfilling. Due to the obligations

  3. 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)

  4. Solid State Culture Conditions for Composting Sewage Sludge

    Directory of Open Access Journals (Sweden)

    N.A. Kabbashi

    2012-10-01

    Full Text Available Composting is applied to treat sewage sludge from treatment plants to enhance its quality and suitability for agricultural use. In this work the optimal conditions for composting sewage sludge from domestic wastewater treatment plants in a horizontal drum bioreactor (HDB were investigated. This study investigated the physico-chemical conditions affecting the use of filamentous fungi in composting. The average number of faecal coliforms was 2.3  107 bacteria/g waste dry weight at the beginning of the composting process, and decreased considerably to 8.2  103, 8.1  103, 8.5  103, 8.0  103,and 8.4  103 bacteria/g, respectively for experiments T1 to T5. This decrease was presumably the result of raising temperature. The phase of hygienisation was marked by a very significant decrease in the number of E. coli cells (1.8  107, to 3.7  103, 3.8  103, 3.3  103, 3.2  103, and 3.6  103 bacteria/g for T1 to T5 experiments, respectively: A second aspect was the investigation of a possible reduction of hazardous pollutants.  The highest concentration was for Fe and the lowest for Pb, showing that Fe is the most loosely bound to the sewage sludge organic matrix and Pb the most strongly bound, the Cd reduction by composting was more than 50%.Keywords: Sewage sludge, compost, horizontal drum bioreactor, hazardous.

  5. Treatment of supernatant from sewage sludge by elctron beam irradiation

    International Nuclear Information System (INIS)

    Arai, Hidehiko; Sugiyama, Masashi; Shimizu, Ken.

    1988-01-01

    Part of the results was presented on the investigation of treatment of supernatant from sewage sludge by combination of electron beam irradiation and microbiological treatment. Supernatant is electron-beam irradiated after microbiologically treated, and then treated microbiologically again. Based this method, by irradiation of 10 kGy, chemical oxygen demand (COD) in supernatant can be decreased lower than 30 ppm. Moreover, electron-beam irradiation induces remarkable decolorization and deodorization. (author)

  6. Joint NRC/EPA Sewage Sludge Radiological Survey: Survey Design & Test Site Results

    Science.gov (United States)

    This report contains the results of a radiological survey of nine publicly POTWs around the country, which was commissioned by the Sewage Sludge Subcommittee, to determine whether and to what extent radionuclides concentrate in sewage treatment wastes.

  7. Activated sewage sludge, a potential animal foodstuff. Part I. Nutritional characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Tacon, A.G.J.

    1979-08-01

    The nutritive value of activated sewage sludge is discussed in terms of its amino acid N, non-amino acid N, carbohydrate, fat, mineral, vitamin and microbial content. Processed activated sewage sludge is described as a stable dark brown material of relatively uniform quality, having a nutritive value broadly equivalent to brewers yeast or a protein-rich cereal. The potential hazards associated with the use of activated sewage sludge as a feed ingredient are discussed. 29 references

  8. Investigation into Total Carbon in Sewage Sludge and Compost

    Directory of Open Access Journals (Sweden)

    Eglė Zuokaitė

    2011-02-01

    Full Text Available The relation between soil and climate change is highly important. The soil is a part of the climate change problem; however, it could also be a part of the solution to the encountered problem. For a better understanding and estimation of climate gas emissions and for slowing down these processes, more investigation in this field is required. Sustainable soil usage could help with saving or even increasing the amount of carbon in the soil. Such process will sustain the balance of climate gas emissions. Soil carbon is an essential element that determines soil fertility. Recently, the importance of organic materials for soil quality and the applicability of sewage sludge to enrich the soil using such materials have been discussed. Sewage sludge as an organic carbon source can improve soil quality. The best way to stabilise and immobilise carbon is mineralisation that occurs in the composting process. The article analyses and evaluates the loss of organic carbon content during the composting process of sewage sludge and explores loss rates by adding various natural supplements (wood shavings and chips, milled bark, grained branches, peat and zeolite.Article in Lithuanian

  9. Thermal utilisation and disposal of sewage sludge; Thermische Klaerschlammverwertung -beseitigung

    Energy Technology Data Exchange (ETDEWEB)

    Baumgart, H.C. [Emscher Genossenschaft/Lippeverband, Essen (Germany). Technischer Vorstand

    2001-07-01

    Sewage sludge combustion - either in an incinerator or for heat or power generation - has always been important and is getting ever more so. From the cost aspect, it makes quite a difference whether sewage sludge is just incinerated or utilised. The author makes it clear that this cost aspect - and what it means to communities and citizens - tends to be neglected by those who favour sewage sludge combustion and utilisation. [German] Die Verbrennung von Klaerschlamm - sei es als Schlammveraschung oder als thermische oder energetische Verwertung - hat schon immer fuer grosse Klaeranlagen einen bedeutenden Stellenwert gehabt. Die Bedeutung der Verbrennung scheint in letzter Zeit sogar zuzunehmen. Unter Kostengesichtspunkten ist es ein grosser Unterschied, ob ein Klaerschlamm nur verascht oder energetisch verwertet wird. Vor dem Hintergrund der allgemeinen Diskussion um die leeren Kassen der Kommunen, um die sogenannte dritte Miete fuer den Buerger und damit die Zumutbarkeit fuer weitere Steigerungen der Abwassergebuehren stoert mich die Bagatellisierung der Kostengesichtspunkte vor allem auf Seiten derer, die die Verbrennung der Klaerschlaemme fordern. (orig.)

  10. Hydrogen production from sewage sludge by steam gasification

    Energy Technology Data Exchange (ETDEWEB)

    Aye, L.; Klinkajorn, P. [Melbourne Univ. International Technologies Centre, Melbourne, Victoria (Australia). Dept. of Civil and Environmental Engineering

    2006-07-01

    Because of the shortage of energy sources in the near future, renewable energy, such as biomass, has become an important source of energy. One of the most common approaches for producing gaseous fuels from biomass is gasification. The main product gases of gasification are hydrogen, carbon monoxide, methane and low molecular weight hydrocarbons. Because of the capability of very low emission at the point of use, the interest in using hydrogen for electrical power generation and in electric-vehicles has been increasing. Hydrogen from biomass steam gasification (SG) is a net zero green house gas emission fuel. Sewage sludge (SS) has a potential to produce hydrogen-rich gaseous fuel. Therefore, hydrogen production from sewage sludge may be a solution for cleaner fuel and the sewage sludge disposal problem. This paper presented the results of a computer model for SSSG by using Gibbs free energy minimization (GFEM) method. The computer model developed was used to determine the hydrogen production limits for various steam to biomass ratios. The paper presented an introduction to renewable energy and gasification and discussed the Gibbs free energy minimization method. The study used a RAND algorithm. It presented the computer model input parameters and discussed the results of the stoichiometric analysis and Gibbs free energy minimization. The energy requirement for hydrogen production was also presented. 17 refs., 1 tab., 6 figs.

  11. Sewage sludge does not induce genotoxicity and carcinogenesis

    Science.gov (United States)

    Silva, Paula Regina Pereira; Barbisan, Luis Fernando; Dagli, Maria Lúcia Zaidan; Saldiva, Paulo Hilário Nascimento

    2012-01-01

    Through a series of experiments, the genotoxic/mutagenic and carcinogenic potential of sewage sludge was assessed. Male Wistar rats were randomly assigned to four groups: Group 1 - negative control; Group 2 - liver carcinogenesis initiated by diethylnitrosamine (DEN; 200 mg/kg i.p.); Group 3 and G4-liver carcinogenesis initiated by DEN and fed 10,000 ppm or 50,000 ppm of sewage sludge. The animals were submitted to a 70% partial hepatectomy at the 3rd week. Livers were processed for routine histological analysis and immunohistochemistry, in order to detect glutathione S-transferase positive altered hepatocyte foci (GST-P+ AHF). Peripheral blood samples for the comet assay were obtained from the periorbital plexus immediately prior to sacrificing. Polychromatic erythrocytes (PCEs) were analyzed in femoral bone-marrow smears, and the frequencies of those micronucleated (MNPCEs) registered. There was no sewage-sludge-induced increase in frequency of either DNA damage in peripheral blood leucocytes, or MNPCEs in the femoral bone marrow. Also, there was no increase in the levels of DNA damage, in the frequency of MNPCEs, and in the development of GST-P AHF when compared with the respective control group. PMID:23055806

  12. Simulation of substrate degradation in composting of sewage sludge

    International Nuclear Information System (INIS)

    Zhang Jun; Gao Ding; Chen Tongbin; Zheng Guodi; Chen Jun; Ma Chuang; Guo Songlin; Du Wei

    2010-01-01

    To simulate the substrate degradation kinetics of the composting process, this paper develops a mathematical model with a first-order reaction assumption and heat/mass balance equations. A pilot-scale composting test with a mixture of sewage sludge and wheat straw was conducted in an insulated reactor. The BVS (biodegradable volatile solids) degradation process, matrix mass, MC (moisture content), DM (dry matter) and VS (volatile solid) were simulated numerically by the model and experimental data. The numerical simulation offered a method for simulating k (the first-order rate constant) and estimating k 20 (the first-order rate constant at 20 o C). After comparison with experimental values, the relative error of the simulation value of the mass of the compost at maturity was 0.22%, MC 2.9%, DM 4.9% and VS 5.2%, which mean that the simulation is a good fit. The k of sewage sludge was simulated, and k 20 , k 20s (first-order rate coefficient of slow fraction of BVS at 20 o C) of the sewage sludge were estimated as 0.082 and 0.015 d -1 , respectively.

  13. The legacy of sewage sludge disposal in New York bight

    Energy Technology Data Exchange (ETDEWEB)

    Buchholtz ten Brink, M.; Casso, M.A. [Geological Survey, Woods Hole, MA (United States); Allison, M.A. [Texas A and M Univ., Galveston, TX (United States); Schleel, J.S.

    1995-12-31

    From 1924 until 1987, New York City disposed of sewage sludge by dumping at the 12-mile dumpsite in 20 m of water off the New York-New Jersey coast. Approximately 125 {times} 10{sup 6} m{sup 3} was deposited, peaking in the early 1980`s. The dumpsite is at the head of the Hudson Shelf Valley, a submerged river channel crossing the continental shelf, in a region of sandy sediments that are regularly reworked by wave action. The introduction of the chemically and texturally distinct `sludge` sediment provides a tracer to study how accumulated anthropogenic deposits are dispersed throughout the region or transferred off the shelf. This work, begun in 1992, focuses on the fate of the material in the valley, ``downstream`` from the dumpsite. Geophysical, chemical, and radiological tools were used to delineate the sedimentary processes, the extent of contaminant dispersal, and the longterm fate of the dump spoils. Sediment derived from the sewage sludge has preferentially deposited on the valley floor relative to the surrounding shelf, resulting in unnaturally high accumulation rates in the upper valley. Dark, sludge-derived sediment is being covered by cleaner deposits from 0 to 26 km downvalley from the dumpsite, but ongoing resuspension and transport of the sediment results in a sewage signal in the uppermost sediments up to 80 km from the dumpsite. Both buried and surface ``sludge`` is subject to biological mixing. The patchy occurrence of the black sediment and interbedded sand layers observed downvalley suggest that resuspension and transport occur episodically, probably during major storm events.

  14. Modelling Analysis of Sewage Sludge Amended Soil

    DEFF Research Database (Denmark)

    Sørensen, P. B.; Carlsen, L.; Vikelsøe, J.

    the plant effluent. The focus in this work is the top soil as this layer is important for the fate of a xenobiotic substance due to the high biological activity. A simple model for the top soil is used where the substance is assumed homogeneously distributed as suggested in the European Union System......The topic is risk assessment of sludge supply to agricultural soil in relation to xenobiotics. A large variety of xenobiotics arrive to the wastewater treatment plant in the wastewater. Many of these components are hydrophobic and thus will accumulate in the sludge solids and are removed from...... for the Evaluation of Substances (EUSES). It is shown how the fraction of substance mass, which is leached, from the top soil is a simple function of the ratio between the degradation half lifetime and the adsorption coefficient. This model can be used in probabilistic risk assessment of agricultural soils...

  15. Characterization study on secondary sewage sludge for replacement in building materials

    Science.gov (United States)

    Kadir, Aeslina Abdul; Sarani, Noor Amira; Aziz, Nurul Sazwana A.; Hamdan, Rafidah; Abdullah, Mohd Mustafa Al Bakri

    2017-09-01

    Recently, environmental issues continually increased since expanded in industrial development and grown in population. Regarding to this activity, it will cause lack management of waste such as solid waste from wastewater treatment plant called sewage sludge. This research presents the characteristic study of sewage sludge, regardless of whether it is appropriate or not to be applied as building materials. The sewage sludge samples were collected from secondary treatment at Senggarang and Perwira under Indah Water Konsortium (IWK) treatment plant. Raw materials were tested with X-ray Fluorescence (XRF) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) in order to determine the composition of sewage sludge and heavy metal concentration contains in sewage sludge. From the study, it was found that sewage sludge contained high amount of Silica Oxide (SiO2) with 13.6%, Sulphur Trioxide (SO3) with 12.64% and Iron Oxide (Fe2O3) with 8.7% which is similar in clay. In addition, sewage sludge also high in Iron (Fe) with 276.2 mg/L followed by Zinc (Zn) with concentration 45.41 mg/L which sewage sludge cannot be directly disposed to landfill. Results from this study demonstrated that sewage sludge has high possibility to be reused as alternative building materials such as bricks and have compatible chemical composition with clay.

  16. Elimination of pathogenic microorganisms contained in sewage sludge by different anaerobic digestion technologies

    International Nuclear Information System (INIS)

    Rodriguez Morales, J. A.; Hernandez Lehmann, A.; Herandez Munoz, A. F.

    2010-01-01

    sewage sludge should be treated to facilitate handling and avoid possible problems like the smell of pathogens. These treatments modify the properties of the sludge making them more suitable for reuse or disposal. (Author) 5 refs.

  17. Heavy metals speciation in soils treated with sewage sludges

    International Nuclear Information System (INIS)

    Forero Hernandez, Adriana; Ballesteros Gonzalez, Maria Ines

    2004-01-01

    The chemical speciation in soils that had been treated with sewage sludge was determined to find out what had occurred to the heavy metals present. This was done nine weeks after sludge application. An incubation assay was realized using 2.5 % w/w sludge level; this is equivalent to 81.5 ton of sludge per hectare. Pots filled with sludge-soil mixture were placed in a greenhouse at temperature between 17 and 25 Celsius degrade, humidity at field capacity distributed in accordance with a random experimental design with four replicates and seven treatments. It was found that the concentration of Cd, Cu, Mn, Pb, and Zn was lower than the limits established by the environmental protection agency (EPA) for soil usage. Also, the organic carbon content, the available nitrogen and phosphorus were in the normal concentration range reported for organic fertilizers. The sludge addition to the soil gave significant increase of the fraction of Cd bounded to organic material as compared with the exchangeable fraction and the fraction bounded to iron-manganese oxides. Cooper showed more affinity for the fraction of iron-manganese oxides. Lead gave a fraction bounded to organic material that was absent in the witness samples. Zinc had a bigger proportion in the fraction associated with iron manganese oxides. Manganese as compared with the other metals showed the biggest unchangeable fraction

  18. Composition and reactivity of ash from sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Willems, M; Pedersen, B; Jorgensen, S S

    1976-01-01

    Sewage sludge and sludge ash produced at 450 to 1050/sup 0/C in the laboratory or in a multiple hearth incinerator were analyzed by chemical and X-ray diffraction methods. Among the ash components were 23 to 32 percent calcium and magnesium phosphates and the following percentages of heavy metals: Zn 0.9, Cu 0.2, Pb 0.1, Cr 0.07, Ni 0.02, and Cd 0.006. As shown by EDTA-extraction, the reactivity of heavy metals was higher in ash produced at 450/sup 0/C than in dry sludge, but lower in ash produced above 800/sup 0/C. Phosphate in the 800 to 900/sup 0/C samples was dissolved in citric acid but not in citrate.

  19. Sewage sludge disintegration by high-pressure homogenization: a sludge disintegration model.

    Science.gov (United States)

    Zhang, Yuxuan; Zhang, Panyue; Ma, Boqiang; Wu, Hao; Zhang, Sheng; Xu, Xin

    2012-01-01

    High-pressure homogenization (HPH) technology was applied as a pretreatment to disintegrate sewage sludge. The effects of homogenization pressure, homogenization cycle number, and total solid content on sludge disintegration were investigated. The sludge disintegration degree (DD(COD)), protein concentration, and polysaccharide concentration increased with the increase of homogenization pressure and homogenization cycle number, and decreased with the increase of sludge total solid (TS) content. The maximum DD(COD) of 43.94% was achieved at 80 MPa with four homogenization cycles for a 9.58 g/L TS sludge sample. A HPH sludge disintegration model of DD(COD) = kNaPb was established by multivariable linear regression to quantify the effects of homogenization parameters. The homogenization cycle exponent a and homogenization pressure exponent b were 0.4763 and 0.7324 respectively, showing that the effect of homogenization pressure (P) was more significant than that of homogenization cycle number (N). The value of the rate constant k decreased with the increase of sludge total solid content. The specific energy consumption increased with the increment of sludge disintegration efficiency. Lower specific energy consumption was required for higher total solid content sludge.

  20. Investigation of Catalytic effect sewage sludge combustion ash in the formation of HAPs

    Energy Technology Data Exchange (ETDEWEB)

    Fullana, A.; Sidhu, S.; Font, R.; Conesa, A.

    2002-07-01

    Incineration is a very important technique in the treatment of sewage sludge. In 1998 approximately 1,5 million and 2,5 million dry tons of sewage sludge were incinerated in the United States and European Union (EU), respectively. In 1985, only 10% of EU sludge was incinerated, but by 2005 approximately 40% of EU sludge is expected to be incinerated. Use of sewage sludge as agricultural fertilizer was considered the best application for sludge until it was discovered that the presence of heavy metals in sludge could contaminate farmland. The limitations facing landfills and recycling plants and the planned ban on sea disposal has led to the expectation that the role of incineration will increase in the future. The expected increase in sludge incineration has also led to increased scrutiny of the main drawback to the incineration of sewage sludge: the formation of hazard air pollutants (HAP). Sewage sludge incineration has been identified as a very important source of HAPs such as chloro benzenes, chloro phenols, and PCDD/Fs. One of the more important characteristics of sewage sludge incineration is the formation of large amounts of ash, which is rich in known HAP formation catalysts such as Cu and Fe. Thus, the sludge incineration ash is expected to play an important role in the formation of HAPs in the post-combustion zone of a sludge incinerator. in this paper, we present results of our investigation of the catalytic effect of sewage sludge ash on the formation of chloro benzenes and chloro phenols. In this study, pyrolytic gas from sewage sludge was used as reaction gas instead of the synthetic organic mix that has been used in most previous HAPs formation studies. (Author) 4 refs.

  1. Applicability of industrial wastewater as carbon source for denitrification of a sludge dewatering liquor.

    Science.gov (United States)

    Chen, Jiazhong; Lee, Yoomin; Oleszkiewicz, Jan A

    2013-01-01

    The applicability of four industrial waste streams from potato processing, canola processing and oil refining, biodiesel production (glycerol), and glycol as substitutes to methanol and ethanol in denitrification of anaerobically digested sludge dewatering liquor (centrate) was evaluated in bench-scale sequencing batch reactors. It was found that glycerol was the best substitute with the specific denitrification rate (SDNR) of 13 mg NO3-N/(g VSS x h) followed by potato processing wastewater at 12mg NO3-N/(g VSS x h). Both substrates produced faster SDNR than methanol's 10mg NO3-N/(g VSS x h); however, they were inferior to ethanol's 17 mg NO3-N/(g VSS x h). Glycol had SDNR of 8 mg NO3-N/(g VSS x h) and demonstrated a very fast acclimation rate, i.e. the response in increased denitrification rate was visible in three days following glycol addition. Canola processing and oil refining wastewater was considered an inappropriate carbon source due to a low SDNR of 5 mg NO3-N/(g VSS x h) and apparent inhibitory effect on nitrification.

  2. Behavior of Ag nanoparticles in soil: Effects of particle surface coating, aging and sewage sludge amendment

    International Nuclear Information System (INIS)

    Whitley, Annie R.; Levard, Clément; Oostveen, Emily; Bertsch, Paul M.; Matocha, Chris J.; Kammer, Frank von der; Unrine, Jason M.

    2013-01-01

    This study addressed the relative importance of particle coating, sewage sludge amendment, and aging on aggregation and dissolution of manufactured Ag nanoparticles (Ag MNPs) in soil pore water. Ag MNPs with citrate (CIT) or polyvinylpyrrolidone (PVP) coatings were incubated with soil or municipal sewage sludge which was then amended to soil (1% or 3% sludge (w/w)). Pore waters were extracted after 1 week and 2 and 6 months and analyzed for chemical speciation, aggregation state and dissolution. Ag MNP coating had profound effects on aggregation state and partitioning to pore water in the absence of sewage sludge, but pre-incubation with sewage sludge negated these effects. This suggests that Ag MNP coating does not need to be taken into account to understand fate of AgMNPs applied to soil through biosolids amendment. Aging of soil also had profound effects that depended on Ag MNP coating and sludge amendment. -- Highlights: •Silver nanoparticle coating affects fate in unamended soils. •Citrated coated silver nanoparticles could be found in pore water for up to six months. •Pre-incubation of silver nanoparticles in sewage sludge negated effects of surface coating. •Weathered or reprecipitated particles found in pore water for up to two months in sludge amended soils. •Particle surface coating, sewage sludge amendment and aging all have important impacts. -- Behavior of manufactured silver nanoparticles in soil depends on surface coating, contact with sewage sludge, and aging

  3. Effects of irradiation of sewage sludge on heavy metal bioavailability

    International Nuclear Information System (INIS)

    Sheppard, S.C.; Mayoh, K.R.

    1986-10-01

    Sewage sludges are a valuable resource to agriculture, but their use is limited by the hazards of pathogens, toxic chemicals and heavy metals. Irradiation can control the pathogens and deactivate some of the toxic chemicals. The relative cost of industrial-scale irradiation using accelerators has decreased progressively. This, coupled with the increasing necessity to recycle wastes, has led to renewed interest in irradiation of sludges. In response to this renewed interest, this report examines what is known about the effects of irradiation on the bioavailability of heavy metals. Very few studies have addressed this topic, although workers in the U.S. have claimed decreased solubility of metals in irradiated sludges. We have also briefly reviewed the general literature on sludge to gain indirect evidence on the likely effects. The scant data, often based on less than ideal experimental methodologies, show no major consistent effects of irradiation on the availability of heavy metals from sludge. The data are not sufficient to rule out such effects entirely, but the effects appear to be fairly subtle and not likely to persist beyond one growth season. 85 refs

  4. Usage of pumice as bulking agent in sewage sludge composting.

    Science.gov (United States)

    Wu, Chuandong; Li, Weiguang; Wang, Ke; Li, Yunbei

    2015-08-01

    In this study, the impacts of reused and sucrose-decorated pumice as bulking agents on the composting of sewage sludge were evaluated in the lab-scale reactor. The variations of temperature, pH, NH3 and CO2 emission rate, moisture content (MC), volatile solid, dissolved organic carbon, C/N and the water absorption characteristics of pumice were detected during the 25days composting. The MC of pumice achieved 65.23% of the 24h water absorptivity within the first 2h at the mass ratio of 0.6:1 (pumice:sewage sludge). Reused pumice increased 23.68% of CO2 production and reduced 21.25% of NH3 emission. The sucrose-decorated pumice reduced 43.37% of nitrogen loss. These results suggested that adding pumice and sucrose-decorated pumice in sludge composting matrix could not only adjust the MC of materials, but also improve the degradation of organic matters and reduce nitrogen loss. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. On the influence of sewage sludge irradiation by gamma radiation on the sludge properties

    International Nuclear Information System (INIS)

    Hegemann, W.

    1976-01-01

    The gamma irradiation is a technically usable method to disinfect sewage sludge. Furthermore, the slurry properties are also improved. After 24 hours' thickening time, a significantly smaller volume of concentrated thick slurry could be removed compared to untreated sludge. On the other hand, a dilution occurs with pasteurization if the heat is introduced by steam, and the initial concentration could not be achieved again even after thickening for 24 hours. The drainability of the treated sludge was also improved by irradiation, expressed by a reduction of the specific filter resistance. The costs are essentially determined by the radiation sources used. If it is technically possible to process reactor wastes in such a manner that they can be used in slurry radiation plants, costs of 3.50-4.00 DM/m 3 treated sludge seem possible. (orig.) [de

  6. Environmental Assessment of Sewage Sludge Management – Focusing on Sludge Treatment Reed Bed Systems

    DEFF Research Database (Denmark)

    Larsen, Julie Dam

    profiles of the STRB system technology and a mechanical treatment technology, constituting a basis for decision-making in relation to choice of technology. A major part of the project involved performance of fieldwork and laboratory work. Data were collected at three Danish, well-operated STRB systems...... assessment were based on international acknowledged standards and recommendations. An attributional LCA approach was chosen, and the loadings and savings for all impact categories were normalised to people equivalents (PE) (the annual loadings and savings provided by one average person). Three sludge...... gasses CH4 and N2O were larger for mechanical dewatered sludge, the net environmental loadings provided to the impact category Climate Change by this technology (S-CEN) and the STRB system technology (S-STRB and S-SPA) ended up being equally sized (9.010-4 PE), despite of higher biological activity...

  7. A study on torrefaction of sewage sludge to enhance solid fuel qualities

    International Nuclear Information System (INIS)

    Poudel, Jeeban; Ohm, Tae-In; Lee, Sang-Hoon; Oh, Sea Cheon

    2015-01-01

    Highlights: • The physio chemical variation of sewage sludge during torrefaction was studied. • Compounds with oxygen were emitted at a temperature lower than that for C x H y . • Sewage sludge torrefaction range was defined between 300 and 350 °C. - Abstract: Torrefaction is a treatment which serves to improve the properties of biomass in relation to thermochemical processing techniques for energy generation. In this study, the torrefaction of sewage sludge, which is a non-lignocellulosic waste was investigated in a horizontal tubular reactor under nitrogen flow at temperature ranging from 150 to 400 °C, for torrefaction residence time varying from 0 to 50 min. The torrefaction kinetics of sewage sludge was studied to obtain the kinetic parameters. The torrefied sewage sludge products were characterized in terms of their elemental composition, energy yield, ash content and volatile fraction. The energy and mass yields decreased with an increase in the torrefaction temperature. From an elemental analysis, the weight percentage of carbon in the sewage sludge increased with an increase in the torrefaction temperature. On the other hand, the weight percentages of hydrogen and oxygen tended to decrease. The gaseous products from torrefaction of sewage sludge were also analyzed. From this work, it was found that the compounds with oxygen were emitted at a temperature lower than that for hydrocarbon gases and the temperatures of 300–350 °C were the optimum torrefaction temperatures for sewage sludge

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

    DEFF Research Database (Denmark)

    Angelidaki, I.; Ahring, B.K.

    1997-01-01

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

  9. 78 FR 34973 - Proposal for Sewage Sludge Incinerators State Plan for Designated Facilities and Pollutants; Indiana

    Science.gov (United States)

    2013-06-11

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 62 [EPA-R05-OAR-2013-0372; FRL-9820-9] Proposal for Sewage Sludge Incinerators State Plan for Designated Facilities and Pollutants; Indiana AGENCY... direct final rulemaking, Indiana's State Plan to control air pollutants from Sewage Sludge Incinerators...

  10. A study on torrefaction of sewage sludge to enhance solid fuel qualities

    Energy Technology Data Exchange (ETDEWEB)

    Poudel, Jeeban [Department of Mechanical Engineering, Kongju National University, 1223-24 Cheonan-Daero, Seobuk, Chungnam 330-717 (Korea, Republic of); Ohm, Tae-In [Department of Civil and Environmental Engineering, Hanbat National University, 125 Dongseo-Daero, Yuseong, Daejeon, 330-717 (Korea, Republic of); Lee, Sang-Hoon [Korea Institute of Energy Technology Evaluation and Planning, 135-502 Teheran-ro 114gil 14, Gangnam-gu, Seoul (Korea, Republic of); Oh, Sea Cheon, E-mail: ohsec@kongju.ac.kr [Department of Environmental Engineering, Kongju National University, 1223-24 Cheonan-Daero, Seobuk, Chungnam 330-717 (Korea, Republic of)

    2015-06-15

    Highlights: • The physio chemical variation of sewage sludge during torrefaction was studied. • Compounds with oxygen were emitted at a temperature lower than that for C{sub x}H{sub y}. • Sewage sludge torrefaction range was defined between 300 and 350 °C. - Abstract: Torrefaction is a treatment which serves to improve the properties of biomass in relation to thermochemical processing techniques for energy generation. In this study, the torrefaction of sewage sludge, which is a non-lignocellulosic waste was investigated in a horizontal tubular reactor under nitrogen flow at temperature ranging from 150 to 400 °C, for torrefaction residence time varying from 0 to 50 min. The torrefaction kinetics of sewage sludge was studied to obtain the kinetic parameters. The torrefied sewage sludge products were characterized in terms of their elemental composition, energy yield, ash content and volatile fraction. The energy and mass yields decreased with an increase in the torrefaction temperature. From an elemental analysis, the weight percentage of carbon in the sewage sludge increased with an increase in the torrefaction temperature. On the other hand, the weight percentages of hydrogen and oxygen tended to decrease. The gaseous products from torrefaction of sewage sludge were also analyzed. From this work, it was found that the compounds with oxygen were emitted at a temperature lower than that for hydrocarbon gases and the temperatures of 300–350 °C were the optimum torrefaction temperatures for sewage sludge.

  11. 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.

  12. Irradiated sewage sludge for increased crop production - III. Macronutrient availability

    International Nuclear Information System (INIS)

    El-Motaium, R.; Badawy, S.H.

    2002-01-01

    Irradiated and non-irradiated sewage sludge, from El-Gabal El-Asfar Farm near Cairo, were applied to tomato (Lycopersicon esculentum cv. GS) grown in a calcareous and a sandy soil at rates of 20, 40, 60, and 80 t/ha. Unfertilized controls and basal-fertilizer treatments were included. Total concentrations of micronutrients (Cu, Zn, Fe, Mn) in sludge-treated calcareous soil were higher than those in the sandy soil, although DTPA-extractable micronutrient concentrations were lower. There were no significant differences between irradiated and non-irradiated sludge treatments in DTPA-extractable and total micronutrient concentrations for the calcareous or the sandy soil. The total micronutrient concentrations for the highest sludge application rate (80 t/ha) were 5,108, 125, 68.2, and 207 μg/g in the calcareous soil and 2,200, 74.8, 43.2, and 139 μg/g in the sandy soil for Fe, Mn, Cu, and Zn, respectively, whereas the DTPA-extractable micronutrient concentrations were 25.0, 6.2, 5.5 and 6.6 μg/g in the calcareous soil and 53.3, 10.1, 7.3 and 9.83 μg/g in the sandy soil, respectively. Highly significant differences were observed in total and available micronutrient concentrations in calcareous and sandy soils among the sludge-application rates. Micronutrient concentrations of tomato leaves and fruits increased with increasing application rates of irradiated and non-irradiated sludge, and were higher in the sandy than in the calcareous soil for the same treatment. Highly significant differences were observed among the sludge-application rates in terms of the concentrations of micronutrients in both leaves and fruits. However, there were no significant differences between the irradiated and non-irradiated sludge treatments in the micronutrient concentrations of leaves and fruits in either soil. Micronutrient uptake increased with increasing rates of application of sludge to the soil, more so in the sandy than in the calcareous soil. The amounts of Fe, Mn, Cu, and Zn

  13. Irradiated sewage sludge for increased crop production - III. Macronutrient availability

    International Nuclear Information System (INIS)

    El-Motaium, R.; Badawy, S.H.

    2002-01-01

    Irradiated and non-irradiated sewage sludge, from El-Gabal El-Asfar Farm near Cairo, were applied to tomato (Lycopersicon esculentum cv. GS) grown in a calcareous and a sandy soil at rates of 20, 40, 60, and 80 t/ha. Unfertilized controls and basal-fertilizer treatments were included. Total concentrations of micronutrients (Cu, Zn, Fe, Mn) in sludge-treated calcareous soil were higher than those in the sandy soil, although DTPAextractable micronutrient concentrations were lower. There were no significant differences between irradiated and non-irradiated sludge treatments in DTPA-extractable and total micronutrient concentrations for the calcareous or the sandy soil. The total micronutrient concentrations for the highest sludge application rate (80 t/ha) were 5,108, 125, 68.2, and 207 μg/g in the calcareous soil and 2,200, 74.8, 43.2, and 139 μg/g in the sandy soil for Fe, Mn, Cu, and Zn, respectively, whereas the DTPA-extractable micronutrient concentrations were 25.0, 6.2, 5.5 and 6.6 μg/g in the calcareous soil and 53.3, 10.1, 7.3 and 9.83 μg/g in the sandy soil, respectively. Highly significant differences were observed in total and available micronutrient concentrations in calcareous and sandy soils among the sludge-application rates. Micronutrient concentrations of tomato leaves and fruits increased with increasing application rates of irradiated and non-irradiated sludge, and were higher in the sandy than in the calcareous soil for the same treatment. Highly significant differences were observed among the sludge-application rates in terms of the concentrations of micronutrients in both leaves and fruits. However, there were no significant differences between the irradiated and non-irradiated sludge treatments in the micronutrient concentrations of leaves and fruits in either soil. Micronutrient uptake increased with increasing rates of application of sludge to the soil, more so in the sandy than in the calcareous soil. The amounts of Fe, Mn, Cu, and Zn

  14. Effect of Sewage Sludge on Some Macronutrients Concentration and Soil Chemical Properties

    Directory of Open Access Journals (Sweden)

    Sakine Vaseghi

    2005-03-01

    Full Text Available Sewage sludge as an organic fertilizer has economic benefits. Land application of sewage sludge improves some soil chemical and physical properties. The objective of this study was to evaluate the effect of sewage sludge on soil chemical properties and macronutrient concentration in acid and calcareous soils. The study was carried out in a greenhouse using factorial experiment design as completely randomized with three replications. Treatments included : four levels of 0 or control, 50, and 100, 200 ton ha-1 sludge and one level of chemical fertilizer (F consisting of 250 kg ha-1 diammonium phosphate and 250 kg ha-1 urea, and soil including soils of Langroud, Lahijan, Rasht, and Isfahan. As a major vegetable , crop spinach (Spinacea oleracea was grown in the treated soils. Soils samples were analyzed for their chemical properties after crop narvesting. Application of sewage sludge significantly increased plant available k, P, total N, organic matter, electrical conductivity and cation exchange in the soils. Soils pH significantly decreased as a result sewage sludge application. The effect of sewage sludge on plant yield was significant. Overall, the results indicated that sewage sludge is potentially a valuable fertilizer. However, the sludge effect on soil EC and heavy metals should be taken into consideration before its widespread use on cropland.

  15. 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.

  16. 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.

  17. Effect of bioleaching on hydrogen-rich gas production by steam gasification of sewage sludge

    International Nuclear Information System (INIS)

    Li, Hanhui; Chen, Zhihua; Huo, Chan; Hu, Mian; Guo, Dabin; Xiao, Bo

    2015-01-01

    Highlights: • Bioleaching can modify the physicochemical property of sewage sludge. • The enhancement is mainly hydrogen. • Bioleaching can enhance the gas production in gasification of sewage sludge. • Study provides an insight for future application of bioleached sewage sludge. - Abstract: Effect of bioleaching on hydrogen-rich gas production by steam gasification of sewage sludge was carried out in a lab-scale fixed-bed reactor. The influence of sewage sludge solids concentrations (6–14% (w/v) in 2% increments) during the bioleaching process and reactor temperature (600–900 °C in 100 °C increments) on gasification product yields and gas composition were studied. Characterization of samples showed that bioleaching treatment, especially in 6% (w/v) sludge solids concentration, led to metal removal effectively and modifications in the physicochemical property of sewage sludge which was favored for gasification. The maximum gas yield (49.4%) and hydrogen content (46.4%) were obtained at 6% (w/v) sludge solids concentration and reactor temperature of 900 °C. Sewage sludge after the bioleaching treatment may be a feasible feedstock for hydrogen-rich gas product.

  18. Fast pyrolysis of lignin, macroalgae and sewage sludge

    DEFF Research Database (Denmark)

    Trinh, Ngoc Trung

    effect on the product distributions of the lignin and sewage sludge PCR pyrolysis, as well as their bio-oil properties with respect to molecular mass distribution, identified GC-MS component compositions, water-insoluble fraction, viscosity, and HHV. A maximum of organic oil yields of lignin and sewage...... samples of wood, char and grinded char with respect to phase transitions, rheological properties, elemental composition, and energy density were investigated. Also pumping properties were investigated at temperatures of 25, 40 and 60 ºC and the solids loading of 0 - 20 wt%. The bioslurries obtained...... of the condenser nozzle and high rotor speed for obtaining high bio-oil. The recognized limitations lead to that the old PCR set-up cannot be safely scaled up and perform well in a continuous mode. Thus a new set-up with significant modifications of reactor and bio-condenser has been manufactured to overcome...

  19. Sewage sludge: guidelines and its use as fertilizer, soil conditioner and forest substrate

    Directory of Open Access Journals (Sweden)

    David Pessanha Siqueira

    2017-12-01

    Full Text Available Sewage sludge is a residue generated after treatment of sewage, being a growing environmental issue due to the increase in wastewater collection and treatment networks. The disposal of these wastes to agricultural land has been presented as the most appropriate, with positive effects indicated by research. However, there are criteria and procedures to be followed  for the sewage sludge legal management. The main guidelines for sewage sludge use in agriculture are presented, as well as its impact on the chemical and physical properties of soils and its performance as a forest substrate, highlighting its strengths and weaknesses.

  20. Macrobenthic succession following the cessation of sewage sludge disposal

    Science.gov (United States)

    Birchenough, Silvana N. R.; Frid, Chris L. J.

    2009-11-01

    Half a million tonnes of sewage sludge was disposed annually over an 18-yr period at a licensed area off the Northumberland coast, UK. The disposal operation ceased in December 1998, providing the ecological opportunity to study macrobenthic changes in relation to theoretical succession models. A transect from the centre of the disposal site to a control station was monitored three times a year (i.e. March, August and December). This study provides a description of the changes in the macrobenthos and physical environment in the initial '3 years' (i.e. 1999 - 2001). During the period of sewage sludge disposal there were indications of an impact on the macrobenthic community with a high total abundance of individuals ( N) and high total number of species ( S) at the stations located in the centre of the disposal ground. During the immediate post-disposal phase the site continued to show a localised increased of individuals and species in the disposal area. Over time the communities showed signs of successional changes when the reduction of organic matter source was eliminated from the natural system. Multivariate analysis demonstrated a clear gradient of change in the community composition between impacted and control stations. While most benthic studies assess re-colonisation and succession stages of macrobenthos by using manipulative field experiments, this study provides an in situ long-term assessment in the offshore environment. This study contributes with information on: i) initial colonization and succession of macrobenthic communities over a large scale and real world data; ii) macrobenthic data into existing successional models and iii) resilience of benthic communities following the cessation of sewage sludge disposal. This information has the potential to contribute to an effective management of the marine communities in the North Sea.

  1. Impacts of Sewage Sludge in Tropical Soil: A Case Study in Brazil

    International Nuclear Information System (INIS)

    Bettiol, W.; Ghini, R.

    2011-01-01

    A long-term assay was conducted to evaluate the environmental impacts of agriculture use of sewage sludge on a tropical soil. This paper describes and discusses the results obtained by applying a interdisciplinary approach and the valuable insights gained. Experimental site was located in Jaguariuna (SP, Brazil). Multiyear comparison was developed with the application of sewage sludge obtained from wastewater treatment plants at Barueri (domestic and industrial sewage) and Franca (domestic sewage), Sao Paulo State. The treatments were control, mineral fertilization, and sewage sludge applied based on the N concentration that provides the same amount of N as in the mineral fertilization recommended for corn crop, two, four, and eight times the N recommended dosage. The results obtained indicated that the amount of sewage sludge used in agricultural areas must be calculated based on the N crop needs, and annual application must be avoided to prevent over applications.

  2. Reclamation of copper mine tailings using sewage sludge

    OpenAIRE

    Stjernman Forsberg, Lovisa

    2008-01-01

    Tailings are the fine-grained fraction of waste produced during mining operations. This work was carried out on tailings from the Aitik copper mine in northern Sweden. Establishment of vegetation on the Aitik mine tailings deposit is planned to take place at closure of the mine, using sewage sludge as fertiliser. However, the tailings contain traces of metal sulphides, e.g. pyrite, FeS2, and chalcopyrite, CuFeS2. When the sulphides are oxidised, they start to weather and release metals and st...

  3. Phytoextraction of heavy metal from sewage sludge by plants

    Directory of Open Access Journals (Sweden)

    Jaroslava Bartlová

    2010-01-01

    Full Text Available In 2008 and 2009, studies made contents of cadmium and lead in the soil and their uptake by non-traditional plants were studied in a small-plot trial. At the same time also the effect of bio-algeen preparations on phytoextraction of heavy metals by these plants was investigated. Experimental plots were established on the reclaimed land after closing down mining operations in the town of Žacléř (North-East Bohemia where a layer of sewage sludge from a wastewater treatment plant 0.6–0.8 m thick was subsequently applied. The locality is situated in the altitude of 612 m, its average annual temperature is about 6.8 °C and the mean annual precipitations are 857 mm. Analyses revealed higher concentrations of heavy metals in the applied sewage sludge. The average concentrations of lead and cadmium were 180 mg . kg−1 and 6.89 mg . kg−1, respectively. The experiment had two variants: Variant 1 – sewage sludge without any other substances, and Variant 2 – sewage sludge + bio-algeen preparations (B. A. S-90 or B. A. Root Concentrate. To find the most suitable plant species for the phytoextraction of cadmium and lead, the following non-traditional plants were cultivated in both variants: fodder mallow (Malva verticillata L., rye (Secale cereale L. var. multicaule METZG. ex ALEF. and white sweet clover (Melilotus alba MEDIC.. The highest accumulation of cadmium and lead in the aboveground biomass was found out in rye, viz 14.89 mg . kg−1 DM and 14.89 mg . kg−1 DM of Cd and Pb, respectively., As compared with other plants under study, white sweet clover exhibited the significantly lowest capability to extract both heavy metals from soil (viz 0.22 and 3.20 mg . kg−1 DM of Cd and Pb, respectively. A positive effect of bio-algeen on phytoextraction of cadmium and lead was evident in all plants. The highest yield of aboveground biomass was recorded on the plot with white sweet clover with added

  4. Results of ultrasonic disintegration of sewage sludge in practice; Ergebnisse des Praxiseinsatzes der Schlammdesintegration mittels Ultraschall

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, E. [IWE-Ingenieurgesellschaft fuer Wasser und Entsorgung mbH, Radebeul (Germany); Friedrich, H. [Fraunhofer-Institut fuer Keramische Technologien und Sinterwerkstoffe (IKTS), Dresden (Germany); Hielscher, H. [Hielscher GmbH, Teltow (Germany)

    1999-07-01

    Using high-performance ultrasonic sludge disintegration in different stages of sewage and sludge treatment is found to be an innovative approach for reducing the accruing amounts of sewage sludge in terms of both mass and volume. By means of practical tests with sludge disintegration at sewage treatment plants, its effects are demonstrated. (orig.) [German] Der Einsatz einer Hochleistungs-Ultraschalltechnik zur Schlammdesintegration in verschiedenen Stufen der Abwasser- und Schlammbehandlung zeigt sich als innovativer Loesungsweg zur weitestgehenden massenmaessigen sowie volumenmaessigen Minimierung des Klaerschlammanfalles. An Hand von Einsatzerprobungen der Desintegration in der Klaeranlagenpraxis werden die Effekte der Desintegration vorgestellt. (orig.)

  5. Life cycle assessment of sewage sludge co-incineration in a coal-based power station.

    Science.gov (United States)

    Hong, Jingmin; Xu, Changqing; Hong, Jinglan; Tan, Xianfeng; Chen, Wei

    2013-09-01

    A life cycle assessment was conducted to evaluate the environmental and economic effects of sewage sludge co-incineration in a coal-fired power plant. The general approach employed by a coal-fired power plant was also assessed as control. Sewage sludge co-incineration technology causes greater environmental burden than does coal-based energy production technology because of the additional electricity consumption and wastewater treatment required for the pretreatment of sewage sludge, direct emissions from sludge incineration, and incinerated ash disposal processes. However, sewage sludge co-incineration presents higher economic benefits because of electricity subsidies and the income generating potential of sludge. Environmental assessment results indicate that sewage sludge co-incineration is unsuitable for mitigating the increasing pressure brought on by sewage sludge pollution. Reducing the overall environmental effect of sludge co-incineration power stations necessitates increasing net coal consumption efficiency, incinerated ash reuse rate, dedust system efficiency, and sludge water content rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Thermodynamic Equilibrium Calculations on Cd Transformation during Sewage Sludge Incineration.

    Science.gov (United States)

    Liu, Jing-yong; Huang, Limao; Sun, Shuiyu; Ning, Xun'an; Kuo, Jiahong; Sun, Jian; Wang, Yujie; Xie, Wuming

    2016-06-01

    Thermodynamic equilibrium calculations were performed to reveal the distribution of cadmium during the sewage sludge incineration process. During sludge incineration in the presence of major minerals, such as SiO2, Al2O3 and CaO, the strongest effect was exerted by SiO2 on the Cd transformation compared with the effect of others. The stable solid product of CdSiO3 was formed easily with the reaction between Cd and SiO2, which can restrain the emissions of gaseous Cd pollutants. CdCl2 was formed more easily in the presence of chloride during incineration, thus, the volatilization of Cd was advanced by increasing chlorine content. At low temperatures, the volatilization of Cd was restrained due to the formation of the refractory solid metal sulfate. At high temperatures, the speciation of Cd was not affected by the presence of sulfur, but sulfur could affect the formation temperature of gaseous metals.

  7. Wood ash to treat sewage sludge for agricultural use

    Energy Technology Data Exchange (ETDEWEB)

    White, R.K. [Clemson Univ., SC (United States)

    1993-12-31

    About 90% of the three million tons of wood ash generated in the United States from wood burning facilities is being landfilled. Many landfills are initiated tipping fees and/or restrictions on the disposal of special wastes such as ash. The purpose of this work was to evaluate (1) the feasibility of using wood ash to stabilize sewage sludge and (2) the fertilizer and liming value of the sludge/ash mixture on plant response and soil pH. Research showed that wood ash, when mixed with sludge, will produce a pH above 12.0, which meets US EPA criteria for pathogen reduction for land application on non-direct food chain crops. Different ratios of wood ash to sludge mixtures were tested and the 1:1 ratio (by weight) was found to be optimal. Five replications of wood ash from four sources were tested for moisture content, pH and fertilizer nutrients. The pH of the ash/sludge mixture (1:1) on day one ranged from 12.4 to 13.2. In most cases the pH remained the same over a 21 day test or only dropped 0.1 to 0.3 units. Analyses of the mixtures showed that heavy metal concentrations (As, B, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, S, Se, Zn) were low. The 1:1 ash/sludge mixture had a calcium carbonate equivalency of 17%. Green house pot studies using tall fescue grass were loadings of 300 to 750 pounds per acre of TKN-N than for 500 lb/acre of 10-10-10 commercial fertilizer. Plant tissue analysis showed N, P, K, Ca, and Mg levels to be within the sufficiency range for tall fescue.

  8. 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

  9. Use of sewage sludge as a fertilizer for increasing soil fertility and crop production

    International Nuclear Information System (INIS)

    Suess, A.

    1997-01-01

    The high nutrient and organic-matter contents of sewage sludge make it a useful soil amendment for farmers. In this study at four locations in Bavaria, the application of sewage sludge produced com yields that were similar to or better than those produced by an equal application (in terms of N) of chemical fertilizer. High rates of sludge (800 m 3 /ha) further improved crop yields, although such are impractical for farmers' fields. Residual beneficial effects of sewage-sludge application were seen also in terms of subsequent yields of barley. Application of sludge also improved biological and physical properties of the soils. More long-term studies are needed to better understand how sewage sludge contributes to the improvement of soil fertility and crop yields. (author)

  10. Bioavailability of nitrogen from sewage sludge using 15N-labelled ammonium sulphate

    International Nuclear Information System (INIS)

    El-Motaium, R.A.

    2001-01-01

    The high nutrient nitrogen and organic matter contents of sewage sludge (SS) make it a potential organic fertilizer for sandy soil. In this study, 15 N-labelled ammonium sulphate was used to investigate the availability of nitrogen from irradiated and non-irradiated sewage sludge to tomato plants. The application of sewage sludge to sandy soil increased dry matter production (DMP), nitrogen yield (NY) and nitrogen recovery (NR) over two successive years. A positive relationship was found between sludge application rate and DMP and NY. The increase was significantly higher (P=0.05) in irradiated than non-irradiated sewage sludge. Total nitrogen derived from non-irradiated sewage sludge are : 48.0, 63.7, 73.5, 105.2 Kg/ha, whereas, the total nitrogen derived from irradiated sewage sludge are: 55.1, 72.5, 88.9, 141.4 Kg/ha corresponding to application rates of 10 t/ha, 20 t/ha, 30 t/ha, respectively. This was attributed to higher dry matter production in the later than the former. A highly significant correlation (0.945**) was found between dry matter production and sludge nitrogen yield (i.e. nitrogen derived from sewage sludge). Fertilizer nitrogen yield (total nitrogen derived from fertilizer) was high in treatment receiving mineral fertilizer, however, the 15 N recovery by tomato was only 13.8%. Soil did not contribute well towards total nitrogen yield in tomato and most nitrogen was derived from sewage sludge. Percent nitrogen derived from sewage sludge was in the range 88-92%, depending on the application rate

  11. A laboratory manual for the determination of inorganic chemical contaminants and nutrients in sewage sludges

    International Nuclear Information System (INIS)

    Smith, R.

    1984-01-01

    In addition to a brief discussion on sewage sludge disposal, sludge contaminants, and the potential beneficial and adverse effects of the various inorganic chemical contaminants and nutrients commonly present in sewage sludge, this technical guide presents a scheme of analysis for the determination of the major inorganic contaminants and nutrients. Safety and simplicity were the main criteria considered in the selection of the various sample pretreatment procedures and analytical techniques

  12. TECHNOLOGICAL AND ENVIRONMENTAL PROBLEMS CONNECTED WITH THERMAL CONVERSION OF SEWAGE SLUDGE

    Directory of Open Access Journals (Sweden)

    Alina Żogała

    2016-02-01

    Full Text Available Overview of the most common technological and environmental problems connected with thermal conversion of sewage sludge was presented in the article. Such issues as the influence of content of moisture and mineral matter on fuel properties of sludge, problem of emission of pollutants, problem of management of solid residue, risk of corrosion, were described. Besides, consolidated characteristic of the most important methods of thermal conversion of sewage sludge, with their advantages and disadvantages, was presented in the paper.

  13. Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece.

    Science.gov (United States)

    Samolada, M C; Zabaniotou, A A

    2014-02-01

    For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a 'zero waste' solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. 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.

  15. CISCO - Combined Cycle with Integrated Sewage Sludge Combustion; Kombi-Anlage mit integrierter Klaerschlam-Verbrennung - CISCO (Combined Cycle with Integrated Sewage Sludge Combustion)

    Energy Technology Data Exchange (ETDEWEB)

    Vockrodt, S.; Leithner, R. [Technische Univ. Braunschweig (Germany). Inst. fuer Waerme- und Brennstofftechnik

    2004-12-01

    A new combined process is presented in which is sewage sludge is dried until it can be combusted, and the heat of combustion is used for sludge drying. (orig.) [German] Mit einer neuen Verfahrenskombination ist es moeglich, Klaerschlamm so weit zu trocknen, dass er verbrannt werden kann, wobei die Verbrennungswaerme zur Trocknung genutzt wird. (orig.)

  16. Co-combustion of sewage sludge; Mitverbrennung von Klaerschlamm

    Energy Technology Data Exchange (ETDEWEB)

    Thome-Kozmiensky, K.J. [Technische Univ. Berlin (Germany). Fachgebiet Abfallwirtschaft

    1998-09-01

    Thermal sewage disposal pursues the following aims: destruction of organic pollutants contained in the sludge; concentration and removal or almost complete fixation of inorganic pollutants in the residue matrix; minimisation of the mass solid residue; production of useful products; utilisation of the caloric content. The thermal treatment chain should be as short as possible; intermediate stages in separate reactors such as digestion, drying, degasification or gasification should be avoided if the material is ultimately to be combusted. The present paper examines and assesses the co-combustion of sewage sludge. [Deutsch] Mit der thermischen Klaerschlammentsorgung werden folgende Ziele verfolgt: - Zerstoerung der im Schlamm enthaltenen organischen Schadstoffe, - Konzentration und Ausschleusung oder weitestgehende Fixierung der anorganischen Schadstoffe in die Reststoffmatrix, - Minimierung der Masse an festen Restabfaellen, - Herstellung verwertbarer Produkte, - Nutzung des Waermeeinhalts. Die thermische Behandlungskette sollte moeglichst kurz sein; Zwischenschritte wie Faulung, Trocknung, Ent- oder Vergasung in getrennten Reaktoren sollten vermieden werden, wenn letztendlich doch verbrannt wird. Das Verfahren der Mitverbrennung von Klaerschlamm wird hier untersucht und bewertet. (orig./SR)

  17. Stability and activity of anaerobic sludge from UASB reactors treating sewage in subtropical regions

    NARCIS (Netherlands)

    Seghezzo, L.; Cuevas, C.M.; Trupiano, A.P.; Guerra, R.G.; Gonzalez, S.M.; Zeeman, G.; Lettinga, G.

    2006-01-01

    The production of small amounts of well-stabilized biological sludge is one of the main advantages of upflow anaerobic sludge bed (UASB) reactors over aerobic wastewater treatment systems. In this work, sludge produced in three pilot-scale UASB reactors used to treat sewage under subtropical

  18. Estrogenic compounds in Tunisian urban sewage treatment plant: occurrence, removal and ecotoxicological impact of sewage discharge and sludge disposal.

    Science.gov (United States)

    Belhaj, Dalel; Athmouni, Khaled; Jerbi, Bouthaina; Kallel, Monem; Ayadi, Habib; Zhou, John L

    2016-12-01

    The occurrence, fate and ecotoxicological assessment of selected estrogenic compounds were investigated at Tunisian urban sewage treatment plant. The influents, effluents, as well as primary, secondary and dehydrated sludge, were sampled and analyzed for the target estrogens to evaluate their fate. All target compounds were detected in both sewage and sludge with mean concentrations from 0.062 to 0.993 μg L -1 and from 11.8 to 792.9 μg kg -1 dry weight, respectively. A wide range of removal efficiencies during the treatment processes were observed, from 6.3 % for estrone to 76.8 % for estriol. Ecotoxicological risk assessment revealed that the highest ecotoxicological risk in sewage effluent and dehydrated sludge was due to 17β-estradiol with a risk quotient (RQ) of 4.6 and 181.9, respectively, and 17α-ethinylestradiol with RQ of 9.8 and 14.85, respectively. Ecotoxicological risk after sewage discharge and sludge disposal was limited to the presence of 17β-estradiol in dehydrated-sludge amended soil with RQ of 1.38. Further control of estrogenic hormones in sewage effluent and sludge is essential before their discharge and application in order to prevent their introduction into the natural environment.

  19. Ceramsite preparation from sea sludge with sewage sludge biochar and its environmental risk assessment

    Science.gov (United States)

    Li, Jie; Yu, Guangwei; Pan, Lanjia; Li, Chunxing; Xie, Shengyu; Wang, Gang; Wang, Yin

    2018-02-01

    Ceramsite were produced from sea sludge (SS) by adding different percentage of sewage sludge biochar (SSB). The characteristics of ceramsite including micrograph and elementary composition were analyzed. In addition, the heavy metals (HMs) fractions, leaching behaviour and potential environmental risk were also investigated. The microstructure of the ceramsite was slit pores and the main elements of the ceramsite were Si, Al and O. The residual fraction (F4) of Cu, Cr and Cd in ceramsite with 100% SS (SS100) reached the maximum (100%, 99% and 100%, respectively), while F4 of Zn and Ni in ceramsite with 80% SS and 20% SSB (SS80) reached the top value of 99.5% and 98%. Moreover, the HMs of feedstock can be immobilized after sintering as ceramsite and the leached amounts of HMs in all ceramsite were much lower than that stated by GB 5085.3-2007. Furthermore, ceramsite preparation from sea sludge with sewage sludge biochar will not bring HMs contamination and potential ecological risk.

  20. Changes in the Concentration of Heavy Metals (Cr, Cd, Ni During the Vermicomposting Process of Sewage Sludge

    Directory of Open Access Journals (Sweden)

    Aušra Zigmontienė

    2014-10-01

    Full Text Available Sewage sludge treatment and utilization is an important issue for a biodegradable waste management strategy. Heavy metals in sewage sludge complicate its use. Vermicomposting is one of the ways to improve the characteristics of sewage sludge and to reduce the residual concentrations of heavy metals. Study on changes in the concentration of heavy metals (Chromium, Nickel and Cadmium, when vermicomposting sewage sludge, was performed using Californian earthworms (Eisenia fetida. For that purpose, 60 kg of sewage sludge from Vilnius Waste Water Treatment Plant were taken thus inserting 1.5 kg of Californian earthworms into it. Optimal conditions for work (optimum temperature, moisture, pH for earthworms to survive were maintained in the course of the study that lasted 120 days and was conducted in June – August. The samples of sewage sludge and earthworms were taken every 10 days. The concentrations of heavy metals in sewage sludge were measured using atomic absorption spectroscopy.

  1. An Experimental Study on Axial Temperature Distribution of Combustion of Dewatered Poultry Sludge in Fluidized bed combustor

    Directory of Open Access Journals (Sweden)

    Abbas A.H.

    2016-01-01

    Full Text Available A laboratory scale bubbling fluidized bed combustor was designed and fabricated to study the combustion of dewatered poultry sludge at different operational parameters. This paper present a study on the influence of equivalent ratio, secondary to primary air ratio and the fuel feed rate on the temperature distribution along the combustor. The equivalent ratio has been changed between 0.8 to 1.4% under poultry sludge feed rate of 10 kg/h and from 0.8 to 1 under poultry sludge feed rate of 15 kg/h. The secondary to primary air ratio was varied from 0.1 to 0.5 at 0.65 m injection height and 1.25 equivalent ratio. The results showed that these factors had a significant influence on the combustion characteristics of poultry sludge. The temperature distribution along the combustor was found to be strongly dependent on the fuel feed rate and the equivalent ratio and it increased when these two factors increased. However, the secondary air ratio increased the temperature in the lower region of the combustor while no significant effect was observed at the upper region of the combustor. The results suggested that the poultry sludge can be used as a fuel with high thermal combustor efficiency.

  2. Effect of gamma irradiation and moisture on microbiological load of sewage sludge

    International Nuclear Information System (INIS)

    Al-Bachir, M.; Al-Adawi, M. A.; Shamma, M.

    2002-07-01

    Concentrated municipal sewage sludge, stored for 2, 4, and 6 months, with moisture content of 2, 20, 40, 60, and 80% were exposed to doses of 0, 1, 2, 3, 4, and 5 kGy in a 60 Co package irradiator. Immediately after irradiation, total microbial count, bacterial pathogens in sewage sludge was determined. Techno-economic feasibility of irradiated sewage according to the moisture content in sewage sludge and the needed irradiation dose to eliminate pathogens was evaluated. The results indicated that, all tested sewage sludge sample, bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and e. coli, were detected. Used doses of gamma irradiation reduced the counts of microorganisms. D 1 0 of total count decreased with increasing the moisture level of sewage sludge. The lowest lethal dose for bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and e. coli is over 5 kGy and 1 kGy in air dried and watered sludge with more than 40% sewage sludge respectively, for samples taken at 2, 4 and 6 months of storage. (author)

  3. Qualitative and Quantitative Assessment of Sewage Sludge by Gamma Irradiation with Pasteurization as a Tool for Hygienization

    Science.gov (United States)

    Priyadarshini, J.; Roy, P. K.; Mazumdar, A.

    2014-01-01

    In this research work, management of sewage sludge disposal on agricultural soils is addressed. The increasing amount of sewage sludge and more legislative regulation of its disposal have stimulated the need for developing new technologies to recycle sewage sludge efficiently. The research was structured along two main avenues, namely, the efficacy of the irradiation process for removing enteric pathogenic microorganisms and the potential of irradiated sludge as a soil amendment. This study investigated how application of irradiation with heat treatment reduced pathogens in sewage sludge. Raw and pasteurised Sewage sludge was treated at different dose treatment of 1.5, 3 and 5 kilogray (kGy) gamma irradiation individually and for 3 kGy sufficiency was achieved. Decrease in irradiation dose from 5 to 3 kGy was observed for pasteurised sludge resulting in saving of radiation energy. The presence of heavy metals in untreated sewage sludge has raised concerns, which decreases after irradiation.

  4. Biological testing of a digested sewage sludge and derived composts.

    Science.gov (United States)

    Moreira, R; Sousa, J P; Canhoto, C

    2008-11-01

    Aiming to evaluate a possible loss of soil habitat function after amendment with organic wastes, a digested sewage sludge and derived composts produced with green residues, where biologically tested in the laboratory using soil animals (Eisenia andrei and Folsomia candida) and plants (Brassica rapa and Avena sativa). Each waste was tested mimicking a field application of 6ton/ha or 12ton/ha. Avoidance tests did not reveal any impact of sludge and composts to soil biota. Germination and growth tests showed that application of composts were beneficial for both plants. Composts did not affect earthworm's mass increase or reproduction, but the highest sludge amendment revealed negative effects on both parameters. Only the amendment of composts at the highest dose originated an impairment of springtails reproductive output. We suggest that bioassays using different test species may be an additional tool to evaluate effects of amendment of organic wastes in soil. Biological tests are sensitive to pollutants at low concentrations and to interactions undetected by routine chemical analysis.

  5. 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.

  6. Heavy metals availability and soil fertility after land application of sewage sludge on dystroferric Red Latosol

    Directory of Open Access Journals (Sweden)

    Rodrigo Santos Moreira

    2013-12-01

    Full Text Available Sewage sludge is the solid residue obtained from urban sewage treatment plants. It is possible to use the sludge in a sustainable way as fertilizer and as soil conditioner due to its high levels of organic matter and nutrients. Besides pathogens and volatile organic compounds, the residue may also contain heavy metals which may accumulate and contaminate crops and the food chain. The aim of this study was evaluates the changes in the fertility of dystrophic Red Latosol and in the availability of heavy metals following application of sewage sludge. It was assessed whether organic matter supplied to the soil as large amounts of sewage sludge would decrease availability of heavy metals in the soil due to of insoluble compounds formation. From this, an experiment was carried out in polyethylene pots using lettuce plant for test. Sewage sludge were applied to the soil in concentrations equivalent to 60, 120 and 180 t ha-1, and a control without sludge, in four replicates, in a completely randomized design. The results show that sewage sludge led to an increase of organic matter contents, of the cation exchange capacity (CEC and of nutrients found in the soil. It also improved plant growth up to a concentration of 120 t ha-1. Availability of heavy metals, however, was reduced in sludge concentrations starting with 120 t ha-1.

  7. Evaluation of the nutritional value of Irradiated sewage sludges reuse in agriculture

    International Nuclear Information System (INIS)

    El-Motaium, R.A.; El-Ammari, M.F.

    2006-01-01

    Four different sludges were collected from wastewater treatment plants and a farm in greater Cairo area. These sludges represent three different treatments: secondary (Helwan), primary (Abou Rawash), digested (El-Gabal El-Asfar) and raw (El-Gabal El-Asfar farm). Half of the collected sludge was exposed to 6 KGy of gamma radiation and the other half was kept non-irradiated. The different parameters measured for this evaluation were ph, EC, total and available nitrogen, total and available phosphorus, total potassium, organic matter, C/N ratio, micro nutrients (Fe, Zn, Cu, Mn) and heavy metals (Cd, Pb, Ni). The data showed that irradiated sewage sludges contain high organic matter, nitrogen, phosphorus, potassium and micro nutrients content. Heavy metals concentrations in the different sludges were less than the international permissible levels for sludge utilization in agriculture. Thus, Egyptian irradiated sewage sludge can be reused for agriculture. Irradiated sewage sludge if applied at 20 t/ha rate can provide plants with their need of macro nutrients (NPK) and micro nutrients (Fe, Zn, Mn, Cu). In the meantime, Cd concentration that can be added to the soil at the same application rate is very small; 0.042-0.108 kg/ha for primary and secondary treated sludge, respectively. Sludge that was treated by digestion showed the highest concentrations of organic matter, nitrogen and phosphorus. Non-significant differences were observed between the ph, EC, OM%, C% and C/N values of irradiated and non-irradiated sewage sludges. In general, no consistent effect of gamma radiation on heavy metals content was recorded. Gamma radiation can impose positive effect on sewage sludge without a reduction of its nutritional value and it is recommended method for sewage sludge treatment

  8. Bioprocessing of sewage sludge for safe recycling on agricultural land - BIOWASTE

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Jens Ejbye; Angelidaki, Irini; Christensen, Nina; Batstone, Damien John; Lyberatos, Gerasimos; Stamatelatou, Katerina; Lichtfouse, Eric; Elbisser, Brigitte; Rogers, Kayne; Sappin-Didier, Valerie; Dernaix, Laurence; Caria; Giovanni; Metzger, Laure; Borghi, Veronica; Montcada, Eloi

    2003-07-01

    Disposal and handling of sewage sludge are increasing problems in Europe due to the increasing quantities of the sewage sludge produced. A large amount of the sewage sludge contains small fractions of toxic chemicals, which results in problems with safe use of the sewage sludge on agricultural land. From an ecological and economical point of view, it would be essential to establish methodologies, which could allow sewage sludge to be reused as fertilizers on agricultural land. Energy efficient biotreatment processes of organic waste are, therefore, of crucial importance. BIOWASTE will offer an integrated study of this area. The typical composition of sewage sludge will be characterized with regard to key contaminating compounds. The following compounds will be in focus: Emulsifying agents such as nonylphenols and nonylphenol ethoxylates (NPE), polycyclic aromatic hydrocarbons (PAHs) derived from incomplete combustion processes and phthalates, which are used as additives in plastics and surfactants such as linear alkyl benzene sulfonate (LAS). Analytical techniques suitable for qualitative and quantitative evaluation of the chemical species involved in the processes under investigation will be determined. Bacteria that are able to degrade selected contaminating compounds under anaerobic and aerobic conditions will be isolated, characterized and bioaugmented for decontamination of sewage sludge through bioprocessing. Aerobic, anaerobic and combination of aerobic/anaerobic bioprocessing of sewage sludge will be applied. A mathematical model will be developed to describe the biodegradation processes of the contaminating compounds after establishing the kinetic parameters for degradation of contaminating compounds. The bioprocessed sewage sludge will be used in eco- and plant- toxicology tests to evaluate the impact of the xenobiotics on the environment. Methodologies will be developed and applied to assess the cleanliness of the bioprocessing as a safe method for waste

  9. Composting of Sewage Sludge Using Recycled Matured Compost as a Single Bulking Agent

    Science.gov (United States)

    Zhang, Xiangyang; Ren, Jian; Niu, Huasi; Wu, Xingwu

    2010-11-01

    Pretreatment (bulking agent choice and mixing) is an essential phase of dewatered raw sludge (RS) composting affecting its industrialization significantly. In this paper recycled compost (RC) was chosen as a single bulking agent in the composting experiment instead of other agents such as sawdust, rice straw, MSW, and the mixing machine was developed for mixing of SS and RC. According to the mixing experiment, SS and RC can be mixed uniformly and formed into small particles of 10˜15 mm in diameter, which improved the availability of oxygen during composting. The effect of different volumetric ratios of RS to RC, 1:1 (Exp.1), 1:2 (Exp.2) and 1:4 (Exp.3), on the performance of composting was investigated in detail. Temperature, oxygen consumption rate, organic matter, C/N ratio and moisture content were monitored in each experiment. In despite of low initial C/N of the mixture, intensive fermentation happened in all the experiments. Exp.1 and Exp.2 achieved stability and sanitization, but Exp 1 took more days to accomplish the fermentation. Exp 3 maintained thermophilic temperatures for a shortest time and did not satisfy the necessary sanitation requirements because more RC was recycled. In all experiments, the moisture content of their final composts were too high to be used as bulking agents before extra moisture was reduced. RS: RC = 1:2 (v/v) was the optimum and advisable proportion for the industrialization of sewage sludge composting of, the composting period was about 10 days, and the aeration rate 0.05 m3/(m3ṡmin) was appropriate in this study.

  10. Transition metal rates in latosol twice treated with sewage sludge

    Directory of Open Access Journals (Sweden)

    Ana Tereza Jordão Pigozzo

    2006-05-01

    Full Text Available Agricultural recycling of sewage sludge has been a source of accumulation of heavy metals in the environment which may reach toxic levels and cause serious damage to the biota. Field experiments were undertaken for two agricultural years (2000 and 2002 and effects of two sewage sludge applications were evaluated through the extraction of (essential and non-essential transition metals by diethylenetriaminepentaacetic acid (DTPA extractor in a medium texture dystrophic Dark Red Latosol. Cd, Ni, Co, Pb and Cr were not detected. Application of sewage sludge initially caused a slight pH rise in the soil; later pH lowered and kept itself close to the starting level. It could be concluded that through consecutive sludge application, extractable rates of Fe and Mn in soil samples gradually increased during the two agricultural years in proportion to sewage sludge doses and sampling period. In fact, they were higher than rates of control. Due to low concentrations of soil samples, extractor had a restricted capacity for evaluation of its phytoavailability.A reciclagem agrícola do lodo de esgoto tem provocado o acúmulo de metais pesados no solo e na água, podendo atingir níveis tóxicos e causar danos às plantas cultivadas, aos animais e ao homem, por meio da cadeia trófica. Neste intuito foi desenvolvido o presente experimento, em condições de campo, entre 2000 e 2002, onde foram avaliados os efeitos da aplicação de lodo de esgoto por dois anos, sobre a extração de metais de transição (essenciais e não pelo extrator DTPA em um Latossolo Vermelho distrófico (LVd de textura média. As concentrações dos elementos metálicos: Mn, Fe, Cd, Ni, Co, Pb e Cr não foram detectados pelo método da absorção atômica na solução obtida com o extrator DTPA. A aplicação de lodo de esgoto causou inicialmente pequena elevação no pH do solo, posteriormente a diminuição do mesmo, e manteve-se próximo ao original. Foi possível concluir que, com

  11. Maximizing the benefits of a dewatering system

    International Nuclear Information System (INIS)

    Matthews, P.; Iverson, T.S.

    1999-01-01

    The use of dewatering systems in the mining, industrial sludge and sewage waste treatment industries is discussed, also describing some of the problems that have been encountered while using drilling fluid dewatering technology. The technology is an acceptable drilling waste handling alternative but it has had problems associated with recycled fluid incompatibility, high chemical costs and system inefficiencies. This paper discussed the following five action areas that can maximize the benefits and help reduce costs of a dewatering project: (1) co-ordinate all services, (2) choose equipment that fits the drilling program, (3) match the chemical treatment with the drilling fluid types, (4) determine recycled fluid compatibility requirements, and (5) determine the disposal requirements before project start-up. 2 refs., 5 figs

  12. Thermal utilisation and disposal of sewage sludge; Thermische Klaerschlammverwertung und -Beseitigung

    Energy Technology Data Exchange (ETDEWEB)

    Dichtl, N. [Technische Univ. Braunschweig (Germany). Inst. fuer Siedlungswasserwirtschaft

    2004-07-01

    In view of the increasing difficulty of getting rid of sewage sludge under the new legal specifications, thermal methods of sewage sludge treatment will become more important. While sewage sludge contains useful material such as carbon, nitrogen, or phosphorus, there are also harmful constituents like heavy metals and organic compounds. Thermal processes will handle these critical constituents, provided that they are really eliminated in the process and not emitted again with the flue gases. Even if thermal processes meet the rigid emission criteria, it should be kept in mind that other useful constituents, especially phosphorus, will remain unused. (orig.)

  13. Incinerated sewage sludge ash as alternative binder in cement-based materials

    DEFF Research Database (Denmark)

    Krejcirikova, Barbora; Goltermann, Per; Hodicky, Kamil

    2013-01-01

    Sewage sludge ash is characterized by its pozzolanic properties, as cement is. This predetermines its use in a substitution of cement and cementitious materials. Utilization of sewage sludge ash does not only decrease the consumption of cement, one of the largest cause of CO2 emissions, but also...... it can minimize the need of ash landfill disposal. The objective of this study is to show potential use of incinerated sewage sludge ash (ISSA), an industrial byproduct, as possible binder in cement-based materials. Chemical and mechanical characteristics are presented and compared with results obtained...

  14. Occurrence of high-tonnage anionic surfactants into Spanish sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Cantarero, S.; Prieto, C. A.; Lopez, I.; Berna, J. L.

    2009-07-01

    The sewage Sludge directive 86/278/EEc seeks to encourage the disposal of sewage sludge in agriculture applications and regulate its use to prevent harmful effects on the soil environment. currently, the sewage sludge Directive is under revision and a possible cut-off limit for some organic chemicals (including linear alkylbenzene sulphonates. LAS, the main synthetic anionic surfactant) is to be implemented. This legal limit is based on monitoring studies carried out in Scandinavian countries, being strongly rejected by most EU countries since the Nordic situations was regarded as not representative. (Author)

  15. Occurrence of high-tonnage anionic surfactants into Spanish sewage sludge

    International Nuclear Information System (INIS)

    Cantarero, S.; Prieto, C. A.; Lopez, I.; Berna, J. L.

    2009-01-01

    The sewage Sludge directive 86/278/EEc seeks to encourage the disposal of sewage sludge in agriculture applications and regulate its use to prevent harmful effects on the soil environment. currently, the sewage sludge Directive is under revision and a possible cut-off limit for some organic chemicals (including linear alkylbenzene sulphonates. LAS, the main synthetic anionic surfactant) is to be implemented. This legal limit is based on monitoring studies carried out in Scandinavian countries, being strongly rejected by most EU countries since the Nordic situations was regarded as not representative. (Author)

  16. 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)

  17. Modeling the Radiological Impact of Tritium in Sewage Sludge Being Used as Fertilizer

    International Nuclear Information System (INIS)

    Venter, A.; Smith, G.

    2005-01-01

    A study was undertaken to assess the radiological impact on humans via the foodchain resulting from the presence of tritium and C-14 in sewage sludge being used as fertilizer on agricultural land. The key endpoint of the assessment was the annual individual dose to an average member of potential critical groups. As part of the assessment, a model was developed to simulate the distribution of tritium between sewage sludge and effluent in the sewage treatment plant, the release of tritium upon sludge decomposition and subsequent uptake by plants and animals. The modeling assumptions, as well as key parameters and parameter values will be discussed in this paper

  18. 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.

  19. Roles of iron species and pH optimization on sewage sludge conditioning with Fenton's reagent and lime.

    Science.gov (United States)

    Yu, Wenbo; Yang, Jiakuan; Shi, Yafei; Song, Jian; Shi, Yao; Xiao, Jun; Li, Chao; Xu, Xinyu; He, Shu; Liang, Sha; Wu, Xu; Hu, Jingping

    2016-05-15

    Conditioning sewage sludge with Fenton's reagent could effectively improve its dewaterability. However, drawbacks of conditioning with Fenton's reagent are requirement of acidic conditions to prevent iron precipitation and subsequent neutralization with alkaline additive to obtain the pH of the filtrate close to neutrality. In this study, roles of pH were thoroughly investigated in the acidification pretreatment, Fenton reaction, and the final filtrate after conditioning. Through the response surface methodology (RSM), the optimal dosages of H2SO4, Fe(2+), H2O2, and lime acted as a neutralizer were found to be 0 (no acidification), 47.9, 34.3 and 43.2 mg/g DS (dry solids). With those optimal doses, water content of the dewatered sludge cakes could be reduced to 55.8 ± 0.6 wt%, and pH of the final filtrate was 6.6 ± 0.2. Fenton conditioning without initial acidification can simplify the conditioning process and reduce the usage of lime. The Fe(3+) content in the sludge cakes showed a close correlation with the dewaterability of conditioned sludge, i.e., the water content of sludge cakes, SRF (specific resistance to filtration), CST (capillary suction time), bound water content, and specific surface area. It indicated that the coagulation by Fe(3+) species in Fenton reaction could play an important role, compared to traditional Fenton oxidation effect on sludge conditioning. Thus, a two-step mechanism of Fenton oxidation and Fe(III) coagulation was proposed in sewage sludge conditioning. The mechanisms include the following: (1) extracellular polymeric substances (EPS) were firstly degraded into dissolved organics by Fenton oxidation; (2) bound water was converted to free water due to degradation of EPS; (3) the sludge particles were disintegrated into small ones by oxidation; (4) Fe(3+) generated from Fenton reaction acted as a coagulant to agglomerate smaller sludge particles into larger dense particles with less bond water; (5) finally, the dewatered

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

    OpenAIRE

    Nyyssönen, Ville

    2015-01-01

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

  1. Effects of Sewage Sludges Contaminated with Chlorinated Aromatic Hydrocarbons on Sludge-Treated Areas (Soils and Sediments

    Directory of Open Access Journals (Sweden)

    Ethel Eljarrat

    2002-01-01

    Full Text Available The fate of PCDDs, PCDFs, and PCBs in sewage sludges after different management techniques — such as agricultural application, land restoration, and marine disposal — was studied. Changes observed in the concentrations, in the ratio between PCDD and PCDF levels, and in the isomeric distribution suggest the influence of the sewage sludge on the sludge-treated areas (soils and sediments. Whereas land application techniques seem to produce no serious environmental consequences, marine disposal practices produce considerable increases in the levels of contamination in marine sediments.

  2. Occurrence of high-tonnage anionic surfactants in Spanish sewage sludge.

    Science.gov (United States)

    Cantarero, Samuel; Prieto, Carlos A; López, Ignacio

    2012-03-01

    Agricultural application has become the most widespread method of sewage sludge disposal, being the most economical outlet for sludge and also recycling beneficial plant nutrients and organic matter to soil for crop production. As a matter of fact, the European Sewage Sludge Directive 86/278/EEC seeks to encourage the disposal of sewage sludge in agriculture applications and regulate its use to prevent harmful effects on the soil environment. At the present time, the sewage sludge Directive is under revision and a possible cut-off limit for some organic chemicals may be implemented. Linear alkylbenzene sulphonate (LAS), the main synthetic anionic surfactant, has been included in the draft list of chemicals to be limited. The present research work deals with the monitoring of LAS and soap in Spanish sewage sludge. The average concentration of LAS found in anaerobic sewage sludge samples was 8.06 g/kg, higher than the average values for European sludge. Besides, it has been also found that more than 55% of Spanish anaerobic sludge would not fulfil the limit proposed by the 3rd European Working paper on sludge. As a consequence, the implementation of the limit for LAS would make the disposal of most Spanish biosolids for agricultural applications almost impossible. Regarding the mechanisms why anionic surfactants are found in sludge, two surfactants are compared: LAS and soap, both readily biodegraded in aerobic conditions. Irrespective of the anaerobic biodegradability of soap, its concentration found in sludge is higher than LAS (only anaerobically biodegradable under particular conditions). The relevance of anaerobic biodegradation to assure environmental protection is discussed for this case. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Beryllium-7 in Rainfall, River Sediment and Sewage Sludge - Beryllium-7 in rainwater, river sediment and sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Helmut W.; Igbinosa, Aimuamwosa; Souti, Maria Evangelia [University of Bremen, Institute of Environmental Physics, Otto-Hahn-Allee 1, D-28359 Bremen (Germany)

    2014-07-01

    profiles, with a clear time delay in the sludge. This behaviour can be explained by the travel time of the isotope through the sewer system. Due to the large delay found (about one week), apart from the relatively fast direct transport of rain water, other processes like deposition/resuspension or erosion may play a role. Due to loss of several monthly samples by external disturbances no coherent results could be obtained for river sediment so far. Conclusion: It could be shown that {sup 7}Be is a useful tracer in terrestrial and surface water studies - the rainfall amount correlates with deposition directly and, after a time delay, with sewage plant primary sludge concentration. The rainfall collection is being continued in order to extend the time series to a minimum of one year. (authors)

  4. Removal of siloxanes in sewage sludge by thermal treatment with gas stripping

    International Nuclear Information System (INIS)

    Oshita, Kazuyuki; Omori, Keigo; Takaoka, Masaki; Mizuno, Tadao

    2014-01-01

    Highlights: • A new treatment of sewage sludge were studied to reduce siloxanes in biogas. • D5 of cyclic siloxane concentrations were the highest in sewage sludge. • Under optimal conditions, most of siloxanes in the sludge were removed previously. • By this treatment, CH 4 was 1.6-fold larger and siloxane in biogas 95% lower. - Abstract: In this study, thermal treatment with gas stripping of sewage sludge before anaerobic digestion to reduce siloxanes in the sludge and accelerate the anaerobic digestion was studied experimentally. Regarding siloxanes in the sludge, D5 concentrations were the highest. Siloxane concentrations in the digested sludge were decreased, versus those in thickened sludge, because siloxanes in the sludge are moved to the biogas during the anaerobic digestion. Thermal treatment and gas stripping experiments were conducted. The optimum conditions for siloxane removal from sludge were found to be thermal treatment with gas stripping at 80 °C with 0.5 L/min of air flow for 48 h. Under these conditions, approximately 90% of all siloxanes in the sludge were removed. Next, anaerobic digestion experiments were conducted with the optimally treated sludge and untreated sludge. The biogas volume of the optimally treated sludge was 1.6-fold larger than that of the untreated sludge. Furthermore, D5 contents in biogas from the optimally treated sludge were 95% lower than in biogas from untreated sludge. Thus, thermal treatment with gas stripping of sludge before anaerobic digestion was effective in increasing biogas amounts, decreasing siloxane concentrations in the biogas, and reducing the need for a siloxane removal process from the biogas

  5. Land reclamation recovery with the sewage sludge use

    Directory of Open Access Journals (Sweden)

    Cristina Rincon Tamanini

    2008-08-01

    Full Text Available In this work, investigations were carried out with five treatments [control, three doses of lime stabilized sludge (60, 120, 240 Mg ha-1 dry base and soil corrective plus mineral fertilizer] to evaluate the immediate recuperation of a borrowed area. The application of stabilized alkaline sewage sludge acted as an acidity corrective, allowed the increase in the organic matter contents (21 to 43.5g dm-3 and available P (44 to 156 mg dm-3. Even with the use of the highest dose, no increase in the concentration of 32 analyzed metals was observed, due to the low concentration of metals in the sludge. The experiment showed that short term restoration of degraded area was possible by using high rates of sewage sludge without metal contamination.Obras de infra-estrutura próximas aos grandes centros levam ao surgimento de áreas degradadas por decapamento que podem ser reintegradas a paisagem através dos processos de recuperação com o uso do lodo de esgoto. Estabeleceu-se um experimento com cinco tratamentos [testemunha, três doses de lodo alcalinizado (60, 120, 240Mgha-1 em base seca e corretivo mais adubo mineral], para avaliar a recuperação imediata de uma área de empréstimo. A aplicação de lodo de esgoto alcalinizado atuou como corretivo da acidez, proporcionou aumento no teor de matéria orgânica (21 para 43,5g dm-3 e P disponível (4,4 para 156mg dm-3 e total, se mostrando superior ao mineral mais calagem. Mesmo com uso da maior dose, não foi observado acréscimos nos teores de 32 metais analisados, dado à baixa concentração de metais no lodo. Os resultados obtidos indicam que é possível o uso de doses elevadas de lodo de esgoto na recuperação de áreas degradadas.

  6. 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.

  7. Preparation of lightweight concretes with sewage sludge ash and their properties

    International Nuclear Information System (INIS)

    Lee, Hwa Young

    2010-01-01

    Sewage sludge results from the accumulation of solids from the unit processes of chemical coagulation, flocculation and sedimentation during wastewater treatment. Rapid urbanization in many areas of the world has resulted in a drastic increase of sewage sludge. More than two million tons of sewage sludge resulted from the treatment of urban sewage is produced annually in Korea. The majority of sewage sludge is disposed of conventionally by the landfill or ocean disposal method, both of which create severe environmental pollution. However, increasingly stringent environmental regulations and scarcity of landfill sites have posed disposal problems of sludge. Incineration is a viable alternative providing a means of sludge stabilization resulting in a reduced volume of sterile, odorless and practically inert residue. Accordingly, the development of environment friendly treatment technique of SSA (sewage sludge ash) inevitably produced during incineration of sewage sludge may be urgently required. For this aim, an attempt to manufacture the lightweight concrete has been made using sewage sludge ash and the physical properties have been determined in terms of specific gravity, compressive strength and thermal conductivity. As a result, the density of specimen prepared with SSA was ranged from 0.6 to 1.4g/ cm 3 and the compressive strength was ranged from 20 to 40kg/ cm 2 . As far as the thermal conductivity of specimen was concerned, it was ranged from 0.3 to 0.6 W/ mK depending on material composition which was far less than that of concrete. It was concluded that the lightweight concretes prepared with SSA could be applicable to building or construction materials such as insulation board and sound absorption material. (author)

  8. 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.

  9. Anaerobic digestion of sewage sludge: French inventory and state of the art

    International Nuclear Information System (INIS)

    Reverdy, A.L.; Dieude-Fauvel, E.; Baudez, J.C.; Ferstler, V.

    2012-01-01

    Following the Kyoto Protocol and the 'Grenelle de l'environnement', France committed itself to develop renewable energies. Methanization is a process which falls within this objective. Anaerobic digestion of organic material generates biogas made of methane (CH 4 ), carbon dioxide (CO 2 ) and water (H 2 O). In 2009, electricity generation from biogas represented only 0, 93% of the renewable electricity production in France. An inventory of facilities and a state of the art of the methanization of sewage sludge on wastewater treatment plants with the inhabitant equivalent of more than 30.000 were realized. They were done with bibliography and surveys. In France, 68 installations of sewage sludge methanization were counted. The primary technology used is a mix reactor in which sewage sludge, heated at deg. C 37, are introduced. Biogas is mainly valued to warm those sludges. Electrical valorization is poor, especially on old installations. Anaerobic digestion of sewage sludge is generally accepted by managers, mainly because of its capacity to reduce sewage sludge quantity and odors. Methanization as listed in France is quite basic. It is performed with digestion series modification, with pretreatments or with co-digestion. Given the quantity of sewage sludge which could be digested, France could increase renewable energies via biogas. However this technology is perfectible in many units because biogas is burned in flares. (authors)

  10. Practical aspects of the pasteurization of sewage sludge by electron irradiation

    International Nuclear Information System (INIS)

    Tauber, M.; Hofmann, E.G.; Offermann, B.P.

    1975-01-01

    Recently the demand for disinfection of sewage sludge has increased. Investigations have shown that the radiation pasteurization of sludge is the most preferable treatment. Up to now most of these investigations have been made with 60 Co radiation sources. However, it is not easy to run an economic and safe process line for the irradiation of sewage sludge with such isotope sources. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. From the standpoint of the limited electron penetration into the material it is desirable to use high-energy electrons (up to 1.5 MeV) whereas from an economic standpoint it may be better to use electrons of lower energies (0.5 to 1 MeV) and to homogenize the sewage sludge to the required thickness. The following parameters must be considered for a commercial process line: effectivity of the electron radiation process; limited penetration of electrons into the material to be irradiated; beam power of electron accelerators required for sewage sludge treatment; safety aspects; economics of the process with regard to electron energy, power and homogenization of the material; and environmental aspects of the installations. The practical aspects of commercial process lines for electron irradiation of sewage sludge and the design of handling equipment are discussed in relation to these parameters. (author)

  11. Phosphorus recovery from sewage sludge ash through an electrodialytic process

    DEFF Research Database (Denmark)

    Guedes, Paula; Couto, Nazare; Ottosen, Lisbeth M.

    2014-01-01

    The electrodialytic separation process (ED) was applied to sewage sludge ash (SSA) aiming at phosphorus (P) recovery. As the SSA may have high heavy metals contents, their removal was also assessed. Two SSA were sampled, one immediately after incineration (SA) and the other from an open deposit (SB......). Both samples were ED treated as stirred suspensions in sulphuric acid for 3,7 and 14 days. After 14 days, phosphorus was mainly mobilized towards the anode end (approx. 60% in the SA and 70% in the SB), whereas heavy metals mainly electromigrated towards the cathode end. The anolyte presented...... a composition of 98% of P, mainly as orthophosphate, and 2% of heavy metals. The highest heavy metal removal was achieved for Cu (ca. 80%) and the lowest for Pb and Fe (between 4% and 6%). The ED showed to be a viable method for phosphorus recovery from SSA, as it promotes the separation of P from the heavy...

  12. Characterization of sewage sludge generated in Rio de Janeiro, Brazil, and perspectives for agricultural recycling

    Directory of Open Access Journals (Sweden)

    Alan Henrique Marques de Abreu

    2017-08-01

    Full Text Available Sanitary sewage collection and treatment is a serious environmental problem in Brazilian cities, as well as the destination of solid waste resulting from this process, i.e. the sewage sludge, a substance rich in organic matter and nutrients, which is normally discarded in landfills. The aim of this study was to characterize the sewage sludge generated in four treatment stations in Rio de Janeiro State, Brazil and check if they meet the legal criteria of the National Environment Council (CONAMA, Resolution No. 375/2006. It also focused on analyzing the perspectives for its agricultural recycling based on the potential demand for main agricultural crops grown in Rio de Janeiro State. Samples from eight sewage sludge lots from four treatment stations located in the metropolitan area of Rio de Janeiro were analyzed. These stations receive and treat only domestic sewage by activated sludge system. For chemical and biological characterization of these lots, representative samples were collected and analyzed according to parameters of CONAMA Resolution No. 375/2006. In order to analyze the perspectives of agricultural recycling of sewage sludge in Rio de Janeiro State, 10 crops with the largest cultivated area in the state were surveyed and analyzed which of them are apt to receive sewage sludge as fertilizer and/or soil amendment. To determine the potential demand for sewage sludge in agriculture, the area occupied by these crops were multiplied by each fertilizer recommendation considering the sewage sludge as fertilizer. The analyzed sludge presented a high content of nutrients and organic matter and was included in the parameters of heavy metals, pathogenic agents, and bacteriological indicators stipulated by CONAMA Resolution No. 375/2006. The agricultural panorama of Rio de Janeiro State is favorable for agricultural recycling of sewage sludge since there is a great potential demand for this residue and, among the 10 agricultural crops with the

  13. Sewage sludge as a biomass resource for the production of energy: Overview and assessment of the various options

    NARCIS (Netherlands)

    Rulkens, W.H.

    2008-01-01

    Treatment of municipal wastewater results worldwide in the production of large amounts of sewage sludge. The major part of the dry matter content of this sludge consists of nontoxic organic compounds, in general a combination of primary sludge and secondary (microbiological) sludge. The sludge also

  14. Effect of pyrolysis temperatures on freely dissolved polycyclic aromatic hydrocarbon (PAH) concentrations in sewage sludge-derived biochars.

    Science.gov (United States)

    Zielińska, Anna; Oleszczuk, Patryk

    2016-06-01

    The aim of this study was to evaluate the effect of sewage sludge pyrolysis on freely dissolved (Cfree) polycyclic aromatic hydrocarbon (PAH) contents in biochars. Four sewage sludges with varying properties and PAH contents were pyrolysed at temperatures of 500 °C, 600 °C or 700 °C. Cfree PAH contents were determined using polyoxymethylene (POM). The contents of Cfree PAHs in the sludges ranged from 262 to 294 ng L(-1). Sewage sludge-derived biochars have from 2.3- to 3.4-times lower Cfree PAH contents comparing to corresponding sewage sludges. The Cfree PAH contents in the biochars ranged between 81 ng L(-1) and 126 ng L(-1). As regards agricultural use of biochar, the lower contents of Cfree PAHs in the biochars compared to the sewage sludges makes biochar a safer material than sewage sludge in terms of PAH contents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Forms of polycyclic aromatic hydrocarbon in the formation of sewage sludge toxicity to Heterocypris incongruens

    International Nuclear Information System (INIS)

    Oleszczuk, Patryk

    2008-01-01

    The aim of the present study was to evaluate to what degree polycyclic aromatic hydrocarbon (PAH) determines sewage sludge toxicity in relation to Heterocypris incongruens. Six differing sewage sludges with increasing contents of polycyclic aromatic hydrocarbons were selected for the present study. As well as total PAH content, the content of the potentially bioavailable fraction was also determined in the sewage sludges using a method of mild-solvent extraction (with n-butanol). The PAH content was also calculated in the sewage sludge pore water by the equilibrium partitioning method. The total PAH content in the sewage sludges studied were in the range 3.60 to 27.95 mg kg -1 . The contribution of the n-butanol extracted fraction was in the range 38.7 to 75.4%. In the group of individual PAHs, 4- and 5-ring compounds had the highest content in the potentially bioavailable group. H. incongruens mortality in the range 6.7 to 100%, depending both on the sewage sludge and the dose applied. An increase of the sewage sludge dose usually resulted in an increase in toxicity. At the highest dose, a 100% mortality of H. incongruens was found in half of the sludges. The lowest dose, irrespective of the sludge type, caused over 40% growth inhibition. However, the results obtained did not allow for the establishing of an unambiguous relationship between various sludge toxicity levels and the content of potentially bio-available PAHs. In some cases only, the extraction using n-butanol explained the high difference in toxicity despite a slight differentiation in the PAH content

  16. Effects of hydrothermal treatment of sewage sludge on pyrolysis and steam gasification

    International Nuclear Information System (INIS)

    Moon, Jihong; Mun, Tae-Young; Yang, Won; Lee, Uendo; Hwang, Jungho; Jang, Ensuk; Choi, Changsik

    2015-01-01

    Highlights: • Hydrothermal treatment (HT) is energy efficient and increases fuel energy density. • Pyrolysis and steam gasification were performed with sewage sludge before/after HT. • Product gases resembled those from wood chips, particularly at high temperature. • HT increases sludge lignin content, possibly enhancing methane yield of product gas. • HT can improve sewage sludge for use as an alternative to biomass and fossil fuels. - Abstract: Hydrothermal treatment is a promising option for pretreatment drying of organic waste, due to its low energy consumption and contribution to increasing fuel energy density. In this study, the characteristics of hydrothermally treated sewage sludge were investigated, and pyrolysis and steam gasification were performed with the sludge before and after hydrothermal treatment. The overall composition of product gases from treated sludge was similar to that obtained from steam gasification of wood chips, particularly under high-temperature conditions. In addition, the increase in lignin content of sewage sludge following hydrothermal treatment could help enhance methane yield in product gas during pyrolysis and steam gasification. The findings suggest that hydrothermal treatment is an appropriate method for improving sewage sludge for use as an alternative to biomass and fossil fuels

  17. Agricultural potential of an industrial sewage sludge in compliance with CONAMA Resolution no. 375/2006

    Directory of Open Access Journals (Sweden)

    Lívia Rodrigues Dias Machado

    2015-12-01

    Full Text Available The agricultural use of sewage sludge is one of the best alternatives to disposal because of its potential as a plant fertilizer and soil conditioner. However, to be safe for agricultural use, the sewage sludge must be evaluated according to its physical, chemical, and biological properties and its origin. In Brazil, NBR 10.004/2004 is the standard that determines the classification of solid waste, and CONAMA Resolution 375/2006 defines the criteria for the agricultural use of sewage sludge. This study evaluated the agricultural potential of an aerobically digested industrial sewage sludge from the Serramar Dairy Cooperative in the city of Guaratinguetá, São Paulo. This sludge was classified as Class IIA waste according to NBR 10.004/2004 and displayed potential for agricultural use by falling within the limits in terms for heavy metals and pathogenic organisms established by Resolution 375/2006 as well as containing high levels of nutrients. To establish the sludge doses allowed for application to crops such as maize (annual and Eucalyptus sp. (perennial by the resolution, the amount of nitrogen available in the sludge and the amounts of this nutrient required by these crops were considered. The recommended sewage sludge doses for corn (8 Mg ha- 1 and Eucalyptus sp. forestation (6 Mg ha- 1 can meet the nitrogen and phosphorus needs of these crops but require supplementation with potassium mineral fertilizer.

  18. Effects of sewage sludge stabilization on fertilizer value and greenhouse gas emissions after soil application

    DEFF Research Database (Denmark)

    Yoshida, Hiroko; Nielsen, Martin P.; Scheutz, Charlotte

    2015-01-01

    was therefore to investigate the effect of sewage sludge stabilization techniques on the C and N mineralization and gaseous emissions from soil. A soil incubation was conducted to determine the rate of C and N mineralization and N2O and CH4 emissions of sewage sludge stabilized using different techniques....... Unstabilized sludge released up to 90% of their C content as CO2, part of which could be caused by release of CO2 from carbonates. Compared with this, sludge stabilization including anaerobic digestion and drying resulted in a reduction of the C mineralization rate of about 40%. Liming reduced C mineralization...... the value of the sludge as a fertilizer. Emissions of CH4 were also reduced through sludge stabilization and mainly occurred after application of easily degradable sludge types, which is likely to have enhanced the creation of anaerobic microsites. The stabilization processes also decreased emissions of N2O...

  19. Life cycle assessment of sewage sludge treatment and its use on land

    DEFF Research Database (Denmark)

    Yoshida, Hiroko

    factors per unit application of N fertiliser on land by fitting a linear mixed-effect model to the outcome of simulations with varying N application levels. It was evident that the effects of inorganic N fertiliser appear immediately after its application, while improvements in crop yield and emissions......Sewage sludge is generated as an end-product of wastewater treatment processes, and its management holds importance in the operation of wastewater treatment plants from both an economic and an environmental point of view. At the same time, the management of sewage sludge is becoming increasingly...... (LCAs) have been applied in the field of sewage sludge management for the past two decades. While providing a flexible platform for comparing a range of sewage sludge management options, a knowledge gap has been identified through the review of existing studies, including inconsistencies in pollutant...

  20. Emission reduction in thermal processes for sewage sludge disposal; Emissionsreduzierung bei thermischen Verfahren zur Klaerschlammentsorgung

    Energy Technology Data Exchange (ETDEWEB)

    Nethe, L.P. [Maerker Umwelttechnik GmbH, Hamburg (Germany)

    1998-09-01

    Owing to the intensification of treatment processes and the construction of new sewage plants sewage arisings are due to rise considerably. The thermal treatment of sewage sludge which it has not been possible to avoid or utilise is an important and indispensable part of any sewage sludge disposal concept. If equipped with a state-of-the-art flue gas purification process that uses carbonaceous adsorbents (Sorbalit trademark), thermal treatment of sewage sludge can be regarded as an environmentally safe process technique. [Deutsch] Die anfallenden Klaerschlammengen werden durch die Intensivierung der Klaerprozesse und der Bau neuer Klaeranlagen deutlich zunehmen. Die thermische Behandlung nicht vermiedener oder verwerteter Klaerschlaemme stellt einen bedeutenden und unverzichtbaren Teil der Klaerschlamm-Entsorgungskonzepte dar. Bei Installation einer - dem Stand der Technik - entsprechenden Rauchgasreinigung mit dem Einsatz kohlenstoffhaltiger Adsorbentien (Sorbalit {sup trademark}) ist die thermische Behandlung von Klaerschlamm eine umweltsichere Verfahrenstechnik. (orig.)

  1. The fate of radionuclides in sewage sludge applied to land

    International Nuclear Information System (INIS)

    Boston, H.L.; Van Miegroet, H.; Larsen, I.L.; Walzer, A.E.; Carlton, J.E.

    1990-01-01

    Municipal sewage sludge containing up to 12 pCi/g 137 Cs, 20 pCi/g 60 Co, and 300 ppm U was injected in a pasture (43 Mg/ha) and sprayed over a young pine plantation (34 Mg/ha). In the pasture, radionuclides were largely retained in the upper 15 cm of the soil, and only about 15% moved below 15 cm. Sludge rapidly infiltrated the soil on the pine plantation. One year after application, at least 85% of the 137 Cs, 60 Co, and U were found in the upper 7 cm of the pine plantation, with only about 15% moving into the 7- to 15-cm strata. On-site total added radiation dose was 2 to 6 mrem/year. Radionuclides were not detected above background in soil solutions at ∼50 cm depth or in shallow down-gradient groundwater wells. Surface runoff from application areas did not have elevated radionuclide concentrations. Concentrations of these radionuclides increased slightly in vegetation on treated sites, and uranium was notably higher in earthworms. 9 refs., 2 tabs

  2. Electrokinetic extraction of surfactants and heavy metals from sewage sludge

    International Nuclear Information System (INIS)

    Ferri, Violetta; Ferro, Sergio; Martinez-Huitle, Carlos A.; De Battisti, Achille

    2009-01-01

    Waste management represents a quite serious problem involving aspects of remediation technologies and potential re-utilization in different fields of human activities. Of course, wastes generated in industrial activities deserve more attention because of the nature and amount of xenobiotic components, often difficult to be eliminated. However, also ordinary wastes of urban origin are drawing more and more attention, depending on the concentration of noxious substances like surfactants and some heavy metal, which may eventually require expensive disposal. In the present paper, a research has been carried out on the application of electrokinetic treatments for the abatement of the above xenobiotic components from sewage sludge generated in urban wastewater treatment plants. Experiments were carried out on a laboratory scale, in a 250 mm x 50 mm x 100 mm cell, using 250-300 g of sludge for each test and current densities between 2.4 and 5.7 mA cm -2 . As a general result, quite significant abatements of heavy-metal ions and surfactants were achieved, with relatively low energy consumption

  3. Relative effectiveness of sewage sludge as a nitrogen fertilizer for tall fescue

    Energy Technology Data Exchange (ETDEWEB)

    Kiemnec, G.L.; Jackson, T.L.; Hemphill, D.D. Jr.; Volk, V.V.

    Sewage sludge application rates on grasses are mainly determined by N availability and concentration of toxic metals in sludge. The exact availability of N in sludge is difficult to predict. A 3-yr study was conducted to determine which sludge rates would give yields of tall fescue (Festuca arundinacea Shreb. Alta) comparable to yields obtained from inorganic N application. Sludge and NH/sub 4/NO/sub 3/ were surface applied at annual rates of 0, 110, 220, 440, and 880 (sludge only) kg N/ha. Dry matter yield of tall fescue from sludge-treated soils was 36, 56, and 50% of that on NH/sub 4/NO/sub 3/-treated soils for 1976, 1977, and 1978, respectively. Sludge was 27, 41, and 44% as effective as NH/sub 4/NO/sub 3/ as a source of available N in 1976, 1977, and 1978, respectively. Ammonium-N in the sewage sludge apparently provided most of the available N for fescue growth. Concentrations of Zn, Cd, and Cu were higher and Mn lower in tall fescue grown on sludge-treated soil with NH/sub 4/NO/sub 3/ and usually increased toward the end of the growing season. However, plant concentrations of these heavy metals never reached toxic levels at any time. Sewage sludge was an effective and safe nutrient source for tall fescue.

  4. Combined (alkaline+ultrasonic) pretreatment effect on sewage sludge disintegration.

    Science.gov (United States)

    Kim, Dong-Hoon; Jeong, Emma; Oh, Sae-Eun; Shin, Hang-Sik

    2010-05-01

    The individual effects of alkaline (pH 8-13) and ultrasonic (3750-45,000kJ/kg TS) pretreatments on the disintegration of sewage sludge were separately tested, and then the effect of combining these two methods at different intensity levels was investigated using response surface methodology (RSM). In the combined pretreatment, ultrasonic treatment was applied to the alkali-pretreated sludge. While the solubilization (SCOD/TCOD) increase was limited to 50% in individual pretreatments, it reached 70% in combined pretreatment, and the results clearly showed that preconditioning of sludge at high pH levels played a crucial role in enhancing the disintegration efficiency of the subsequent ultrasonic pretreatment. By applying regression analysis, the disintegration degree (DD) was fitted based on the actual value to a second order polynomial equation: Y=-172.44+29.82X(1)+5.30x10(-3)X(2)-7.53x10(-5)X(1)X(2)-1.10X(1)(2)-1.043x10(-7)X(2)(2), where X(1), X(2), and Y are pH, specific energy input (kJ/kg TS), and DD, respectively. In a 2D contour plot describing the tendency of DD with respect to pH and specific energy input, it was clear that DD increased as pH increased, but it seemed that DD decreased when the specific energy input exceeded about 20,000kJ/kg TS. This phenomenon tells us that there exists a certain point where additional energy input is ineffective in achieving further disintegration. A synergetic disintegration effect was also found in the combined pretreatment, with lower specific energy input in ultrasonic pretreatment yielding higher synergetic effect. Finally, in order to see the combined pretreatment effect in continuous operation, the sludge pretreated with low intensity alkaline (pH 9)/ultrasonic (7500kJ/kg TS) treatment was fed to a 3 L of anaerobic sequencing batch reactor after 70 days of control operation. CH(4) production yield significantly increased from 81.9+/-4.5mL CH(4)/g COD(added) to 127.3+/-5.0mL CH(4)/g COD(added) by pretreatment, and

  5. 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

  6. Amendment of the EC Sewage Sludge Regulation and the German Sewage Sludge Ordinance; Novellierung der EG-Klaerschlammrichtlinie und der deutschen Klaerschlammverordnung

    Energy Technology Data Exchange (ETDEWEB)

    Bergs, C.G.; Krebsbach, A. [Bundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Berlin (Germany)

    2001-03-01

    The EC Sewage Sludge Guideline of 12 June 1996 laid down the boundary conditions for sewage sludge utilisation in agriculture. The purpose of the regulation was the standardisation of member states regulations on sewage sludge treatment and the harmonisation of limiting values for pollutant emissions in the EC member states. [German] Mit der 'Richtlinie des Rates vom 12. Juni 1996 ueber den Schutz der Boeden bei der Verwendung von Klaerschlamm in der Landwirtschaft' (86/278/EWG) hat die Europaeische Kommission EU-weite Rahmenvorgaben fuer die landwirtschaftliche Klaerschlammverwertung geschaffen. Ziel der Richtlinie war es, eine Rechtsangleichung der Regelungen ueber die Klaerschlammverwertung und eine Harmonisierung der Schadstoffgrenzwerte in den Mitgliedstaaten zu erreichen. (orig.)

  7. PAHs content of sewage sludge in Europe and its use as soil fertilizer

    Energy Technology Data Exchange (ETDEWEB)

    Suciu, Nicoleta A., E-mail: nicoleta.suciu@unicatt.it; Lamastra, Lucrezia; Trevisan, Marco

    2015-07-15

    Highlights: • Sewage sludge contamination by PAHs may restrict its use as soil fertilizer. • Long term data concerning sewage sludge contamination by PAHs is lacking. • Literature review for EU countries and monitoring data for Italy is presented. • Focus PEARL model was used to simulate B(a)Pyr, the most toxic PAH, fate in soil. • The simulated B(a)Pyr soil concentration was much lower than its LOEC for soil organisms. - Abstract: The European Commission has been planning limits for organic pollutants in sewage sludge for 14 years; however no legislation has been implemented. This is mainly due to lack of data on sewage sludge contamination by organic pollutants, and possible negative effects to the environment. However, waste management has become an acute problem in many countries. Management options require extensive waste characterization, since many of them may contain compounds which could be harmful to the ecosystem, such as heavy metals, organic pollutants. The present study aims to show the true European position, regarding the polycyclic aromatic hydrocarbons (PAHs) content of sewage sludge, by comparing the Italian PAHs content with European Union countries, and at assessing the suitability of sewage sludge as soil fertilizer. The FOCUS Pearl model was used to estimate the concentration of benzo [a] pyrene (B(a)Pyr), the most toxic PAH in soil, and its exposure to organisms was then evaluated. The simulated B(a)Pyr and PAHs, expressed as B(a)Pyr, concentrations in soil were much lower than the B(a)Pyr’s most conservative lowest observable effect concentration (LOEC) for soil organisms. Furthermore, the results obtained indicate that it is more appropriate to apply 5 t ha{sup −1} sewage sludge annually than 15 t ha{sup −1} triennially. Results suggest, the EU maximum recommended limit of 6 mg kg{sup −1} PAHs in sewage sludge, should be conservative enough to avoid groundwater contamination and negative effects on soil organisms.

  8. Interaction of alkylphenolic and perfluorinated compounds with sewage sludges and soils

    OpenAIRE

    Milinovic, Jelena

    2014-01-01

    [eng] In this doctoral thesis the interaction of emergent organic pollutants, such as alkylphenolic and perfluorinated compounds (APCs and PFCs, respectively) with sewage sludge and soil samples was studied. These two families of organic compounds were selected because of their ubiquitous presence and persistence in environmental matrices and to know mechanisms responsible for their interaction. With respect to the behaviour of APCs in sewage sludges, concretely octylphenol (OP), nonylphenol ...

  9. The use of reed canary grass and giant miscanthus in the phytoremediation of municipal sewage sludge.

    Science.gov (United States)

    Antonkiewicz, Jacek; Kołodziej, Barbara; Bielińska, Elżbieta Jolanta

    2016-05-01

    The application of municipal sewage sludge on energy crops is an alternative form of recycling nutrients, food materials, and organic matter from waste. Municipal sewage sludge constitutes a potential source of heavy metals in soil, which can be partially removed by the cultivation of energy crops. The aim of the research was to assess the effect of municipal sewage sludge on the uptake of heavy metals by monocotyledonous energy crops. Sewage sludge was applied at doses of 0, 10, 20, 40, and 60 Mg DM · ha(-1) once, before the sowing of plants. In a 6-year field experiment, the effect of four levels of fertilisation with sewage sludge on the uptake of heavy metals by two species of energy crops, reed canary grass (Phalaris arundinacea L.) of 'Bamse' cultivar and giant miscanthus (Miscanthus × giganteus GREEF et DEU), was analysed. It was established that the increasing doses of sewage sludge had a considerable effect on the increase in biomass yield from the tested plants. Due to the increasing doses of sewage sludge, a significant increase in heavy metals content in the energy crops was recorded. The heavy metal uptake with the miscanthus yield was the highest at a dose of 20 Mg DM · ha(-1), and at a dose of 40 Mg DM · ha(-1) in the case of reed canary grass. Research results indicate that on account of higher yields, higher bioaccumulation, and higher heavy metal uptake, miscanthus can be selected for the remediation of sewage sludge.

  10. PAHs content of sewage sludge in Europe and its use as soil fertilizer

    International Nuclear Information System (INIS)

    Suciu, Nicoleta A.; Lamastra, Lucrezia; Trevisan, Marco

    2015-01-01

    Highlights: • Sewage sludge contamination by PAHs may restrict its use as soil fertilizer. • Long term data concerning sewage sludge contamination by PAHs is lacking. • Literature review for EU countries and monitoring data for Italy is presented. • Focus PEARL model was used to simulate B(a)Pyr, the most toxic PAH, fate in soil. • The simulated B(a)Pyr soil concentration was much lower than its LOEC for soil organisms. - Abstract: The European Commission has been planning limits for organic pollutants in sewage sludge for 14 years; however no legislation has been implemented. This is mainly due to lack of data on sewage sludge contamination by organic pollutants, and possible negative effects to the environment. However, waste management has become an acute problem in many countries. Management options require extensive waste characterization, since many of them may contain compounds which could be harmful to the ecosystem, such as heavy metals, organic pollutants. The present study aims to show the true European position, regarding the polycyclic aromatic hydrocarbons (PAHs) content of sewage sludge, by comparing the Italian PAHs content with European Union countries, and at assessing the suitability of sewage sludge as soil fertilizer. The FOCUS Pearl model was used to estimate the concentration of benzo [a] pyrene (B(a)Pyr), the most toxic PAH in soil, and its exposure to organisms was then evaluated. The simulated B(a)Pyr and PAHs, expressed as B(a)Pyr, concentrations in soil were much lower than the B(a)Pyr’s most conservative lowest observable effect concentration (LOEC) for soil organisms. Furthermore, the results obtained indicate that it is more appropriate to apply 5 t ha −1 sewage sludge annually than 15 t ha −1 triennially. Results suggest, the EU maximum recommended limit of 6 mg kg −1 PAHs in sewage sludge, should be conservative enough to avoid groundwater contamination and negative effects on soil organisms

  11. Role of soil properties in sewage sludge toxicity to soil collembolans

    OpenAIRE

    Domene, X.

    2010-01-01

    Soil properties are one of the most important factors explaining the different toxicity results found in different soils. Although there is knowledge about the role of soil properties on the toxicity of individual chemicals, not much is known about its relevance for sewage sludge amendments. In particular little is known about the effect of soil properties on the toxicity modulation of these complex wastes. In addition, in most studies on sewage sludges the identity of the main substances lin...

  12. Thermal treatment of sewage sludge from waste water. Tratamiento termico de lodos procedentes de aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Andreottola, G. (Universidad de Trento (Italy)); Canziani, R.; Ragazzi, M. (Politicnico de Milan (Italy))

    1994-01-01

    Thermal Treatment of sewage sludge can be beneficial as a pre-treatment step of many treatment/disposal options, but above all, it allows the recovery of the energetic content sludge. Energy recovery from sewage sludge can be performed in many ways; direct incineration thermal drying followed by incineration and co-combustion with municipal solid wastes or other non conventional fuels. Another option is the recovery of waste energy (e.g. from an endo thermal engine using biogas as fuel) to dry sludge wich, in turn can be used as a fuel. The paper will evaluate several options of thermal treatment of sewage sludge, with particular emphasis on the energetic yield from different processes. (Author)

  13. Ensured waste disposal without thermal treatment of sewage sludge?; Entsorgungssicherheit ohne thermische Klaerschlammbehandlung?

    Energy Technology Data Exchange (ETDEWEB)

    Melsa, A.K. [Niersverband, Viersen (Germany)

    1998-07-01

    The Technical Rule on Domestic Waste Management (TASi) specifies that from 2005, sewage sludge containing more than 5% of organic dry matter must no longer be dumped. This means that sewage sludge combustion will be the only means of disposal, apart from using sewage sludge as a fertilizer. The author's employer ('Niersverband' utility) was among the first to develop a future-oriented sewage sludge disposal strategy, and a drying plant was construct which is to reduce the weight and volume of sewage sludge in order to obtain a fuel of high calorific value. Further, a contract was closed for combustion of sewage sludge as fuel in a combustion system. [German] Unter Beruecksichtigung der TASi, die verlangt, dass spaetestens ab dem Jahr 2005 Klaerschlaemme mit einem hoeheren organischen Feststoffgehalt als 5% nicht mehr abgelagert werden duerfen, verbleibt uns neben der stofflichen Verwertung in der Landwirtschaft als massgeblicher Entsorgungsweg die Verbrennung, und zwar nicht - und das ist zu unterstreichen - um die Schadstoffe im Klaerschlamm zu beseitigen, sondern um den Klaerschlamm zu entsorgen. Eine betriebssichere Klaerschlammverbrennung stellt dabei die hoechste erreichbare Stufe der Entsorgungssicherheit dar. Der Niersverband hat sich fruehzeitig mit der Aufstellung einer zukunftsfaehigen Klaerschlammentsorgungsstrategie befasst und eine Trocknungsanlage geplant, die eine weitgehende Gewichts- und Volumenreduktion des Klaerschlamms sowie die Erzeugung eines heizwertreichen Brennstoffs gewaehrleistet und damit die Entsorgungsmoeglichkeiten deutlich verbessert. Des weiteren wurde ein erster Vertrag zur energetischen Klaerschlammverwertung in einer Verbrennungsanlage abgeschlossen. (orig.)

  14. Soil Microbial Functional and Fungal Diversity as Influenced by Municipal Sewage Sludge Accumulation

    Directory of Open Access Journals (Sweden)

    Magdalena Frąc

    2014-08-01

    Full Text Available Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS and from a sewage sludge landfill that was 3 m from a SS landfill (SS3 were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Average Well Color Development (AWCD, Richness (R and Shannon-Weaver index (H were calculated to interpret the results. The fungi isolated from the sewage sludge were identified using comparative rDNA sequencing of the LSU D2 region. The MicroSEQ® ID software was used to assess the raw sequence files, perform sequence matching to the MicroSEQ® ID-validated reference database and create Neighbor-Joining trees. Moreover, the genera of fungi isolated from the soil were identified using microscopic methods. Municipal sewage sludge can serve as a habitat for plant pathogens and as a source of pathogen strains for biotechnological applications.

  15. Soil microbial functional and fungal diversity as influenced by municipal sewage sludge accumulation.

    Science.gov (United States)

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy; Jezierska-Tys, Stefania; Nwaichi, Eucharia Oluchi

    2014-08-28

    Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS) and from a sewage sludge landfill that was 3 m from a SS landfill (SS3) were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Average Well Color Development (AWCD), Richness (R) and Shannon-Weaver index (H) were calculated to interpret the results. The fungi isolated from the sewage sludge were identified using comparative rDNA sequencing of the LSU D2 region. The MicroSEQ® ID software was used to assess the raw sequence files, perform sequence matching to the MicroSEQ® ID-validated reference database and create Neighbor-Joining trees. Moreover, the genera of fungi isolated from the soil were identified using microscopic methods. Municipal sewage sludge can serve as a habitat for plant pathogens and as a source of pathogen strains for biotechnological applications.

  16. Effectiveness of DTPA Chelate on Cd Availability in Soils Treated with Sewage Sludge

    Directory of Open Access Journals (Sweden)

    Pegah Houshyar

    2017-09-01

    Full Text Available Application of sewage sludge as a fertilizer on farmlands is a common practice in most countries. Although the practice may play a positive role in plant performance, the organic amendments introduced may increase the soil heavy metals content. This study was conducted in Arak, Iran, to investigate the effectiveness of DTPA chelate on corn Cd availability in a sewage sludge treated soil. The treatments consisted of sewage sludge (0, 15, and 30 t ha-1 polluted with cadmium applied at 0, 5, 10, and 15 mg kg-1 as well as DTPA applied at 0 and 1.5 mmol kg-1 soil. Corn plants were then grown in the soil in each treatmnent and, on day 60, the physic-chemical characteristics and Cd quantities were measured ion both the corn plants and soil samples. Application of 1.5 m mol of DTPA chelate in soil contaminated with 5 mg Cd led to a significant increase in the soil available Cd content. It was also observed that application of DTPA chelate to soils containing 30 t ha-1 of sewage sludge polluted with 10 mg Cd increased root and shoot Cd concentrations by 17 and 25%, respectively. Results indicated the effectiveness of DTPA chelate in reducing Cd phytoremediation with increasing sewage sludge loading rate. This was evidenced by the lowest phytoremediation effectiveness observed for the treatment with the greatest sewage sludge loading (30 t ha-1 and the lowest cadmium pollution (5 mg Cd.

  17. Medium-Chain Chlorinated Paraffins (CPs) Dominate in Australian Sewage Sludge.

    Science.gov (United States)

    Brandsma, Sicco H; van Mourik, Louise; O'Brien, Jake W; Eaglesham, Geoff; Leonards, Pim E G; de Boer, Jacob; Gallen, Christie; Mueller, Jochen; Gaus, Caroline; Bogdal, Christian

    2017-03-21

    To simultaneously quantify and profile the complex mixture of short-, median-, and long-chain CPs (SCCPs, MCCPs, and LCCPs) in Australian sewage sludge, we applied and further validated a recently developed novel instrumental technique, using quadrupole time-of-flight high resolution mass spectrometry running in the negative atmospheric pressure chemical ionization mode (APCI-qTOF-HRMS). Without using an analytical column the cleaned extracts were directly injected into the qTOF-HRMS followed by quantification of the CPs by a mathematical algorithm. The recoveries of the four SCCP, MCCP and LCCP-spiked sewage sludge samples ranged from 86 to 123%. This APCI-qTOF-HRMS method is a fast and promising technique for routinely measuring SCCPs, MCCPs, and LCCPs in sewage sludge. Australian sewage sludge was dominated by MCCPs with concentrations ranging from 542 to 3645 ng/g dry weight (dw). Lower SCCPs concentrations (<57-1421 ng/g dw) were detected in the Australian sewage sludge, which were comparable with the LCCPs concentrations (116-960 ng/g dw). This is the first time that CPs were reported in Australian sewage sludge. The results of this study gives a first impression on the distribution of the SCCPs, MCCPs, and LCCPs in Australia wastewater treatment plants (WWTPs).

  18. 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.

  19. Yield of castor bean fertilized with sewage sludge and potassium and magnesium sulphate

    Directory of Open Access Journals (Sweden)

    Thâmara F. M. Cavalcanti

    2015-08-01

    Full Text Available ABSTRACTThe aim of this study was to evaluate the yield and nutrition of castor bean in response to fertilization with sewage sludge and potassium (K and magnesium (Mg sulphate. The experiment was carried out from January to July 2011. The treatments, in a randomized block design with three replicates, in a Nitosol, corresponded to a factorial scheme (2 x 4 +1: two doses of K and Mg sulphate combined with four doses of sewage sludge (0, 2.60, 5.20 and 10.40 t ha-1, dry basis, applied based on its nitrogen (N content and the N requirement for the crop and an additional treatment with NPK. The castor bean grain yield fertilized with sewage sludge did not differ from conventional fertilization, with the maximum value achieved at a dose of 7.5 t ha-1 of sewage sludge. The fertilization with sewage sludge increased zinc and copper levels in the soil to values close to or higher than those in conventional fertilization, without any influence on the concentrations in the leaf. Fertilization with K and Mg sulphate increased the levels of these cations in the soil without affecting the concentrations in the leaves. The fertilization with sewage sludge increased the contents of organic matter, sulfur, zinc, iron, copper and boron in the soil, and manganese and boron in castor bean leaves.

  20. Novel Concept of an Installation for Sustainable Thermal Utilization of Sewage Sludge

    Directory of Open Access Journals (Sweden)

    Wilhelm Jan Tic

    2018-03-01

    Full Text Available This study proposes an innovative installation concept for the sustainable utilization of sewage sludge. The aim of the study is to prove that existing devices and technologies allow construction of such an installation by integration of a dryer, torrefaction reactor and gasifier with engine, thus maximizing recovery of the waste heat by the installation. This study also presents the results of drying tests, performed at a commercial scale paddle dryer as well as detailed analysis of the torrefaction process of dried sewage sludge. Both tests aim to identify potential problems that could occur during the operation. The scarce literature studies published so far on the torrefaction of sewage sludge presents results from batch reactors, thus giving very limited data of the composition of the torgas. This study aims to cover that gap by presenting results from the torrefaction of sewage sludge in a continuously working, laboratory scale, isothermal rotary reactor. The study confirmed the feasibility of a self-sustaining installation of thermal utilization of sewage sludge using low quality heat. Performed study pointed out the most favorable way to use limited amounts of high temperature heat. Plasma gasification of the torrefied sewage sludge has been identified that requires further studies.

  1. Co-digestion of cultivated microalgae and sewage sludge from municipal waste water treatment.

    Science.gov (United States)

    Olsson, Jesper; Feng, Xin Mei; Ascue, Johnny; Gentili, Francesco G; Shabiimam, M A; Nehrenheim, Emma; Thorin, Eva

    2014-11-01

    In this study two wet microalgae cultures and one dried microalgae culture were co-digested in different proportions with sewage sludge in mesophilic and thermophilic conditions. The aim was to evaluate if the co-digestion could lead to an increased efficiency of methane production compared to digestion of sewage sludge alone. The results showed that co-digestion with both wet and dried microalgae, in certain proportions, increased the biochemical methane potential (BMP) compared with digestion of sewage sludge alone in mesophilic conditions. The BMP was significantly higher than the calculated BMP in many of the mixtures. This synergetic effect was statistically significant in a mixture containing 63% (w/w VS based) undigested sewage sludge and 37% (w/w VS based) wet algae slurry, which produced 23% more methane than observed with undigested sewage sludge alone. The trend was that thermophilic co-digestion of microalgae and undigested sewage sludge did not give the same synergy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. 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.

  3. Soil Microbial Functional and Fungal Diversity as Influenced by Municipal Sewage Sludge Accumulation

    Science.gov (United States)

    Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy; Jezierska-Tys, Stefania; Nwaichi, Eucharia Oluchi

    2014-01-01

    Safe disposal of municipal sewage sludge is a challenging global environmental concern. The aim of this study was to assess the response of soil microbial functional diversity to the accumulation of municipal sewage sludge during landfill storage. Soil samples of a municipal sewage sludge (SS) and from a sewage sludge landfill that was 3 m from a SS landfill (SS3) were analyzed relative to an undisturbed reference soil. Biolog EcoPlatesTM were inoculated with a soil suspension, and the Average Well Color Development (AWCD), Richness (R) and Shannon-Weaver index (H) were calculated to interpret the results. The fungi isolated from the sewage sludge were identified using comparative rDNA sequencing of the LSU D2 region. The MicroSEQ® ID software was used to assess the raw sequence files, perform sequence matching to the MicroSEQ® ID-validated reference database and create Neighbor-Joining trees. Moreover, the genera of fungi isolated from the soil were identified using microscopic methods. Municipal sewage sludge can serve as a habitat for plant pathogens and as a source of pathogen strains for biotechnological applications. PMID:25170681

  4. assessment of trace metals in sewage water and sludge from river ...

    African Journals Online (AJOL)

    UCHEGBU

    2009-08-17

    Aug 17, 2009 ... water), the speciation of metals in the sewage sludge from the drainage basin, and the risk to sewage .... evaluate the digestion process and the effectiveness of AAS .... for irrigation, as it might not affect soil infiltration rate due.

  5. ISCORS ASSESSMENT OF RADIOACTIVITY IN SEWAGE SLUDGE: MODELING TO ASSESS RADIATION DOSES

    Science.gov (United States)

    The Interagency Steering Committee on Radiation Standards (ISCORS) has recently completed a study of the occurrence within the United States of radioactive materials in sewage sludge and sewage incineration ash. One component of that effort was an examination of the possible tran...

  6. The use of municipal sewage sludge for the stabilization of soil contaminated by mining activities.

    Science.gov (United States)

    Theodoratos, P; Moirou, A; Xenidis, A; Paspaliaris, I

    2000-10-02

    The ability of municipal sewage sludge to immobilize Pb, Zn and Cd contained in contaminated soil originating from a former mining area in Lavrion, Greece was investigated. The soil was cured with sewage sludge in various proportions. The stabilization was evaluated primarily by applying chemical tests and complemented by the performance of additional biological tests. Application of the U.S. EPA Toxicity Characteristic Leaching Procedure (TCLP) on the stabilized mixtures proved that Pb, Zn and Cd solubility was reduced by 84%, 64% and 76%, respectively, at 15% w/w sludge addition, while a 10% w/w addition was sufficient to reduce Pb solubility below the U.S. EPA TCLP regulatory limit. The results of the extraction using EDTA solution showed the same trend, resulting in 26%, 36% and 53% reduction in the Pb, Zn and Cd extractable fractions, respectively. Speciation analysis of the treated soils revealed a significant decrease in the mobile fractions of heavy metals, which was attributed to their retention in sewage sludge by adsorption and organic complexation mechanisms. For the assessment of possible phytotoxicity, experiments including growing dwarf beans in the treated soil was carried out. It was found that sewage sludge addition had a positive effect on plant growth. Furthermore, the Pb and Zn uptake of plant leaves and roots was reduced, while Cd uptake was unaffected by the sludge treatment. The results of this study support the hypothesis that municipal sewage sludge is a potential effective stabilizing agent for contaminated soil containing Pb, Zn and Cd.

  7. Effect of acid detergent fiber in hydrothermally pretreated sewage sludge on anaerobic digestion process

    Science.gov (United States)

    Takasaki, Rikiya; Yuan, Lee Chang; Kamahara, Hirotsugu; Atsuta, Youichi; Daimon, Hiroyuki

    2017-10-01

    Hydrothermal treatment is one of the pre-treatment method for anaerobic digestion. The application of hydrothermal treatment to sewage sludge of wastewater treatment plant has been succeeded to enhance the biogas production. The purpose of this study is to quantitatively clarify the effect of hydrothermal treatment on anaerobic digestion process focusing on acid detergent fiber (ADF) in sewage sludge, which is low biodegradability. The hydrothermal treatment experiment was carried out for 15 minutes between 160 °C and 200 °C respectively. The ADF content was decreased after hydrothermal treatment compared with untreated sludge. However, ADF content was increased when raising the treatment temperature from 160 °C to 200 °C. During batch anaerobic digestion experiment, untreated and treated sludge were examined for 10 days under 38 °C, and all samples were fed once based on volatile solids of samples. From batch anaerobic digestion experiment, as ADF content in sewage sludge increased, the total biogas production decreased. It was found that ADF content in sewage sludge influence on anaerobic digestion. Therefore, ADF could be one of the indicator to evaluate the effect of hydrothermal treatment to sewage sludge on anaerobic digestion.

  8. Experience with a pilot plant for the irradiation of sewage sludge: Experiments on the inactivation of viruses in sewage sludge after radiation treatment

    International Nuclear Information System (INIS)

    Epp, C.

    1975-01-01

    Investigations examining the virus inactivating effect of a 60 Co-plant have up to now been limited to attempts to isolate virus from sludge samples taken from sewage sludge before and after irradiation with 300 krad. As in these sludge samples the presence of virus could be proved only on a rather irregular basis, an experiment was carried out in which defined virus quantities were packed into capsules and mixed with the digested sludge. At the end of the hygienization process these capsules were removed from the sludge and examined for virus content. In addition one radiation volume (5.6 m 3 ) was infected with attenuated polio virus type I and the virus content of the sludge titrated before and after the radiation treatment. (author)

  9. Use of Municipal Sewage Sludge for Improvement of Forest Sites in the Southeast

    Science.gov (United States)

    Charles R. Berry

    1987-01-01

    In eight field experiments dried municipal sewage sludge was applied to forest sites before planting of seedlings. In all cases, tree growth was faster on sludge-amended plots than on plots that received fertilizer and lime or no amendment. Deep subsoiling was beneficial regardless of Soil amendment. Where weeds were plentiful at the outset, they became serious...

  10. Electrodialytic treatment for metal removal from sewage sludge ash from fluidized bed combustion

    DEFF Research Database (Denmark)

    Pazos, Marta; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2010-01-01

    Sewage sludge contains several potentially hazardous compounds such as heavy metals, PCBs, PAHs, etc. However, elements with high agricultural value (P, K or Ca) are also present. During the last years, the fluidized bed sludge combustor (FBSC) is considered an effective and novel alternative to ...

  11. A 25-year record of polycyclic aromatic hydrocarbons in soils amended with sewage sludges

    DEFF Research Database (Denmark)

    Lichtfouse, Eric; Sappin-Didier, Valérie; Denaix, Laurence

    2005-01-01

    We studied polycyclic aromatic hydrocarbons (PAHs) in crop soils amended with 1000 tonnes dry weight of sewage sludges per 10,000 m(2) from 1974 to 1992, then after sludges addition from 1993 to 1999. The absence of variations of total PAHs levels of control soils, averaging at 123 mu g/Kg, shows...

  12. Influence analysis of sewage sludge methane fermentation parameters on process efficiency

    Directory of Open Access Journals (Sweden)

    Катерина Борисівна Сорокіна

    2016-12-01

    Full Text Available The efficiency dependence of sewage sludge organic matter decomposition from organization and conditions of the process is analyzed. Support of the optimal values of several parameters ensures to provide completeness of the sludge fermentation process and obtain biogas in calculated amount. Biogas utilization reduces costs for reactor heating and provides additional obtaining of other types of energy

  13. Influence analysis of sewage sludge methane fermentation parameters on process efficiency

    OpenAIRE

    Катерина Борисівна Сорокіна

    2016-01-01

    The efficiency dependence of sewage sludge organic matter decomposition from organization and conditions of the process is analyzed. Support of the optimal values of several parameters ensures to provide completeness of the sludge fermentation process and obtain biogas in calculated amount. Biogas utilization reduces costs for reactor heating and provides additional obtaining of other types of energy

  14. POTENTIAL AND PROPERTIES OF THE GRANULAR SEWAGE SLUDGE AS A RENEWABLE ENERGY SOURCE

    Directory of Open Access Journals (Sweden)

    Sebastian Werle

    2014-10-01

    Full Text Available The predominant method of the sewage sludge management in Poland is land disposal. However, since 01/01/2013, this method will be prohibited. Therefore, there is a strong need for development of thermal methods of sludge disposal. In the Polish legal system sewage sludge may be named as a biomass or waste. For purposes of determining the obligations of environmental regulations definition of the Minister of Environment should be used. When disposing of sewage sludge in an amount up to 1% by weight of fuel, emission standards for fuel do not change. At the disposal of sewage in quantities of more than 1%, should be conducted continuous measurement of emissions, including HCl, HF, and continuous measurements of flue gas parameters (as for the installation of waste disposal. For purposes of settlement of the share of energy from renewable sources we use the definition of Minister of Economy. In this case, in accordance with applicable law sewage sludge shall be considered as pure biomass is CO2 neutral. The use of sewage sludge as a fuel requires the determination of fundamental combustible properties. These properties should be in accordance with the requirements put fuels as an energy source. The paper presents results of a detailed physico-chemical analysis of dried sewage sludge produced in the two Polish wastewater treatment plants. The results were compared with five representatives of biomass fuels: straw of wheat, straw of rape, willow, pine and oak sawdust. Ultimate and proximate analysis includes a detailed analysis of fuel and ash. The results clearly indicate that the sludge is a very valuable fuel similar to “traditional” biomass.

  15. A preliminary study on the effects of sewage sludge disposal on soil polluted by heavy metals

    International Nuclear Information System (INIS)

    Calace, N.; Maggi, C.; Pellegrini, F.; Petronio, B. M.; Pietroletti, M.

    1998-01-01

    A preliminary study on the effects of sewage sludge disposal on soil polluted by heavy metal has been carried out in order to evaluate the possibility of reducing heavy metal mobility. Sewage sludge disposal on soil polluted by zinc and lead can modify their speciation, immobilizing a portion of metal present in mobile forms. In this way environmental hazards due to heavy metal presence can be reduced, because these derive essentially from the amount of metal present in mobile chemical forms. The results obtained show that sludge addition increases the fraction of metal sorbed from the soil; the characterization of the sludge before and after the treatment with the soil point out that this behaviour can be ascribed both to organic substances present in the sludge with the creation of new adsorbing sites, and to an increase of the ph value of the soil, due to the organic and inorganic compounds in the sludge [it

  16. Sewage sludge management strategies, volumes and disposal cost - a Europe-wide comparison; Entsorgungswege, Klaerschlammmengen und Entsorgungskosten im europaeischen Vergleich

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-07-01

    About 60 percent of the sewage sludge produced in the EU are used in agriculture or landscaping, at significantly lower cost than thermal disposal. If the EU were to banish the use of sewage sludge for these purposes, the cost of sewage sludge disposal would increase by about 40 percent. The same would apply in case of a hygienisation law. In this case, thermal utilisation would be preferable. (orig.)

  17. Improving material and energy recovery from the sewage sludge and biomass residues

    Energy Technology Data Exchange (ETDEWEB)

    Kliopova, Irina, E-mail: irina.kliopova@ktu.lt; Makarskienė, Kristina

    2015-02-15

    Highlights: • SRF production from 10–40 mm fraction of pre-composted sludge and biomass residues. • The material and energy balance of compost and SRF production. • Characteristics of raw materials and classification of produced SRF. • Results of the efficiency of energy recovery, comparison analysis with – sawdust. - Abstract: Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives of sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10–40 mm) of pre-composted materials – sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg{sup −1} of the net calorific value, about 23% were composted, the rest – evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning

  18. Improving material and energy recovery from the sewage sludge and biomass residues

    International Nuclear Information System (INIS)

    Kliopova, Irina; Makarskienė, Kristina

    2015-01-01

    Highlights: • SRF production from 10–40 mm fraction of pre-composted sludge and biomass residues. • The material and energy balance of compost and SRF production. • Characteristics of raw materials and classification of produced SRF. • Results of the efficiency of energy recovery, comparison analysis with – sawdust. - Abstract: Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives of sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10–40 mm) of pre-composted materials – sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg −1 of the net calorific value, about 23% were composted, the rest – evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning

  19. Beneficial uses program. Progress report ending December 31, 1978. [Irradiated sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    1979-03-01

    The Beneficial Uses Program is a comprehensive program to develop the necessary technologies for cost-beneficial uses of existing and future surplus radioactive materials. The major portion of the work at Sandia is concentrated in two sub-programs: The Waste Resources Utilization Program and the Separation Technology and Source Development Program. Progress is reported on: (1) the Sandia Irradiator for Dried Sewage Sludge; (2) bacteriology; (3) mycology; (4) virology; (5) animal feeds containing irradiated sewage solids; (6) use of irradiated sewage sludge as fertilizer; and (7) development of /sup 90/Sr and /sup 137/Cs radiation sources obtained from radioactive wastes. (TFD)

  20. Characterization program in the framework of the national sewage sludge plan in Spain

    International Nuclear Information System (INIS)

    Lopez Lopez, M. J.

    2009-01-01

    Sewage Sludge is the waste originated from the process of treatment of waste water. Due to the physical-chemical processes involved in the treatment, the sludge tends to concentrate heavy metals and poorly biodegradable trace organic compounds as well as potentially pathogenic organisms (viruses, bacteria, etc.). However, sludge is rich in nutrients such as nitrogen and phosphorous and contains valuable organic matter that is useful when soils are depleted or subject to erosion. (Author)

  1. 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

  2. Near-bottom pelagic bacteria at a deep-water sewage sludge disposal site

    Energy Technology Data Exchange (ETDEWEB)

    Takizawa, M.; Straube, W.L.; Hill, R.T.; Colwell, R.R.

    1994-01-01

    The epibenthic bacterial community at deep-ocean sewage sludge disposal site DWD-106, located approximately 106 miles (ca. 196 km) off the coast of New Jersey, was assessed for changes associated with the introduction of large amounts of sewage sludge. Mixed cultures and bacterial isolates obtained from water overlying sediment core samples collected at the deep-water (2,500 m) municipal sewage disposal site were tested for the ability to grow under in situ conditions of temperature and pressure. The responses of cultures collected at a DWD-106 station heavily impacted by sewage sludge were compared with those of samples collected from a station at the same depth which was not contaminated by sewage sludge. Significant differences were observed in the ability of mixed bacterial cultures and isolates from the two sites to grow under deep-sea pressure and temperature conditions. The levels of sludge contamination were established by enumerating Clostridium perfringens, a sewage indicator bacterium, in sediment samples from the two sites. (Copyright (c) 1993, American Society for Microbiology.)

  3. Comparative evaluation of microbial and chemical leaching processes for heavy metal removal from dewatered metal plating sludge

    International Nuclear Information System (INIS)

    Bayat, Belgin; Sari, Bulent

    2010-01-01

    The purpose of the study described in this paper was to evaluate the application of bioleaching technique involving Acidithiobacillus ferrooxidans to recover heavy metals (Zn, Cu, Ni, Pb, Cd and Cr) in dewatered metal plating sludge (with no sulfide or sulfate compounds). The effect of some conditional parameters (i.e. pH, oxidation-reduction potential (ORP), sulfate production) and operational parameters (i.e. pulp density of the sludge and agitation time) were investigated in a 3 l completely mixed batch (CMB) reactor. The metal recovery yields in bioleaching were also compared with chemical leaching of the sludge waste using commercial inorganic acids (sulfuric acids and ferric chloride). The leaching of heavy metals increased with decreasing of pH and increasing of ORP and sulfate production during the bioleaching experiment. Optimum pulp density for bioleaching was observed at 2% (w/v), and leaching efficiency decreased with increasing pulp density in bioleaching experiments. Maximum metal solubilization (97% of Zn, 96% of Cu, 93% of Ni, 84% of Pb, 67% of Cd and 34% of Cr) was achieved at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 ± 2 deg. C during the bioleaching process. The maximum removal efficiencies of 72% and 79% Zn, 70% and 75% Cu, 69% and 73% Ni, 57% and 70% Pb, 55% and 65% Cd, and 11% and 22% Cr were also attained with the chemical leaching using sulfuric acids and ferric chloride, respectively, at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 ± 2 deg. C during the acid leaching processes. The rates of metal leaching for bioleaching and chemical leaching are well described by a kinetic equation related to time. Although bioleaching generally requires a longer period of operation compared to chemical leaching, it achieves higher removal efficiency for heavy metals. The efficiency of leaching processes can be arranged in descending order as follows: bioleaching > ferric chloride leaching > sulfuric acid

  4. Comparative evaluation of microbial and chemical leaching processes for heavy metal removal from dewatered metal plating sludge

    Energy Technology Data Exchange (ETDEWEB)

    Bayat, Belgin, E-mail: bbayat@cu.edu.tr [Department of Environmental Engineering, Faculty of Engineering and Architecture, Cukurova University, Balcali, Adana 01330 (Turkey); Sari, Bulent [Department of Environmental Engineering, Faculty of Engineering and Architecture, Cukurova University, Balcali, Adana 01330 (Turkey)

    2010-02-15

    The purpose of the study described in this paper was to evaluate the application of bioleaching technique involving Acidithiobacillus ferrooxidans to recover heavy metals (Zn, Cu, Ni, Pb, Cd and Cr) in dewatered metal plating sludge (with no sulfide or sulfate compounds). The effect of some conditional parameters (i.e. pH, oxidation-reduction potential (ORP), sulfate production) and operational parameters (i.e. pulp density of the sludge and agitation time) were investigated in a 3 l completely mixed batch (CMB) reactor. The metal recovery yields in bioleaching were also compared with chemical leaching of the sludge waste using commercial inorganic acids (sulfuric acids and ferric chloride). The leaching of heavy metals increased with decreasing of pH and increasing of ORP and sulfate production during the bioleaching experiment. Optimum pulp density for bioleaching was observed at 2% (w/v), and leaching efficiency decreased with increasing pulp density in bioleaching experiments. Maximum metal solubilization (97% of Zn, 96% of Cu, 93% of Ni, 84% of Pb, 67% of Cd and 34% of Cr) was achieved at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 {+-} 2 deg. C during the bioleaching process. The maximum removal efficiencies of 72% and 79% Zn, 70% and 75% Cu, 69% and 73% Ni, 57% and 70% Pb, 55% and 65% Cd, and 11% and 22% Cr were also attained with the chemical leaching using sulfuric acids and ferric chloride, respectively, at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 {+-} 2 deg. C during the acid leaching processes. The rates of metal leaching for bioleaching and chemical leaching are well described by a kinetic equation related to time. Although bioleaching generally requires a longer period of operation compared to chemical leaching, it achieves higher removal efficiency for heavy metals. The efficiency of leaching processes can be arranged in descending order as follows: bioleaching > ferric chloride leaching > sulfuric

  5. Fate of triclosan in field soils receiving sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Butler, E [Department of Environmental Science and Technology, School of Applied Sciences, Cranfield University, College Road, Cranfield, Bedfordshire MK43 0AL (United Kingdom); Whelan, M J; Sakrabani, R [Department of Environmental Science and Technology, School of Applied Sciences, Cranfield University, College Road, Cranfield, Bedfordshire MK43 0AL (United Kingdom); Egmond, R van [Safety and Environmental Assurance Centre, Unilever Colworth Laboratory, Colworth Park, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom)

    2012-08-15

    The anti-microbial substance triclosan can partition to sewage sludge during wastewater treatment and subsequently transfer to soil when applied to land. Here, we describe the fate of triclosan in a one-year plot experiment on three different soils receiving sludge. Triclosan and methyl-triclosan concentrations were measured in soil samples collected monthly from three depths. A large fraction of triclosan loss appeared to be explained by transformation to methyl-triclosan. After 12 months less than 20% of the initial triclosan was recovered from each soil. However, the majority was recovered as methyl-triclosan. Most of the chemical recovered at the end of the experiment (both triclosan and methyl-triclosan) was still in the top 10 cm layer, although there was translocation to lower soil horizons in all three soils. Between 16.5 and 50.6% of the applied triclosan was unaccounted for after 12 months either as a consequence of degradation or the formation of non-extractable residues. - Highlights: Black-Right-Pointing-Pointer We study the fate of triclosan in 3 different field soils amended with biosolids. Black-Right-Pointing-Pointer Triclosan concentrations were measured over 12 months at 3 depths of soil. Black-Right-Pointing-Pointer Methyl-triclosan was identified as a main biotransformation product. Black-Right-Pointing-Pointer There was very little movement of triclosan through the soil. Black-Right-Pointing-Pointer Only between 16 and 50% of triclosan applied was degraded or leached out of the soil. - This paper investigates the mobility and degradation of triclosan in three field soils after receiving an application of biosolids and the persistence of methyl-triclosan.

  6. Fate of triclosan in field soils receiving sewage sludge

    International Nuclear Information System (INIS)

    Butler, E.; Whelan, M.J.; Sakrabani, R.; Egmond, R. van

    2012-01-01

    The anti-microbial substance triclosan can partition to sewage sludge during wastewater treatment and subsequently transfer to soil when applied to land. Here, we describe the fate of triclosan in a one-year plot experiment on three different soils receiving sludge. Triclosan and methyl-triclosan concentrations were measured in soil samples collected monthly from three depths. A large fraction of triclosan loss appeared to be explained by transformation to methyl-triclosan. After 12 months less than 20% of the initial triclosan was recovered from each soil. However, the majority was recovered as methyl-triclosan. Most of the chemical recovered at the end of the experiment (both triclosan and methyl-triclosan) was still in the top 10 cm layer, although there was translocation to lower soil horizons in all three soils. Between 16.5 and 50.6% of the applied triclosan was unaccounted for after 12 months either as a consequence of degradation or the formation of non-extractable residues. - Highlights: ► We study the fate of triclosan in 3 different field soils amended with biosolids. ► Triclosan concentrations were measured over 12 months at 3 depths of soil. ► Methyl-triclosan was identified as a main biotransformation product. ► There was very little movement of triclosan through the soil. ► Only between 16 and 50% of triclosan applied was degraded or leached out of the soil. - This paper investigates the mobility and degradation of triclosan in three field soils after receiving an application of biosolids and the persistence of methyl-triclosan.

  7. Integrated drying and incineration of wet sewage sludge in combined bubbling and circulating fluidized bed units.

    Science.gov (United States)

    Li, Shiyuan; Li, Yunyu; Lu, Qinggang; Zhu, Jianguo; Yao, Yao; Bao, Shaolin

    2014-12-01

    An original integrated drying and incineration technique is proposed to dispose of sewage sludge with moisture content of about 80% in a circulating fluidized bed. This system combines a bubbling fluidized bed dryer with a circulating fluidized bed incinerator. After drying, sewage sludge with moisture less than 20% is transported directly and continuously from the fluidized bed dryer into a circulating fluidized bed incinerator. Pilot plant results showed that integrated drying and incineration is feasible in a unique single system. A 100 t/d Sewage Sludge Incineration Demonstration Project was constructed at the Qige sewage treatment plant in Hangzhou City in China. The operational performance showed that the main operation results conformed to the design values, from which it can be concluded that the scale-up of this technique is deemed both feasible and successful. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Sewage sludge disposal-requirements, expense and acceptance; Klaerschlammentsorgung zwischen Anspruch, Aufwand und Akzeptanz

    Energy Technology Data Exchange (ETDEWEB)

    Gruenebaum, T. [Ruhrverband, Essen (Germany)

    1997-02-01

    Production of sewage sludges is unavoidable at wastewater treatment. Sewage sludges shall be used in agriculture. Although the content of hazardous substances in sewage sludges has obviously been minimized, the use of those sludges is limited because of the low acceptance in agriculture and food industry. Therefore it is necessary to build up methods of disposal which make possible and ensure a medium- or even longtime disposal. Incineration seems to be the solution since the requirements for landfill of sewage sludges have been renewed. The currently valid transitional regulation lead to remarkable reactions of the disposal market. The plans for sewage sludge disposal have to agree with the principles of environmental protection, safety, economic efficiency, good realization and operational handling. (orig.) [Deutsch] Bei der Abwasserreinigung faellt Klaerschlamm an. Dieser ist moeglichst in der Landwirtschaft zu verwerten. Obwohl die Schadstoffgehalte der Klaerschlaemme in den letzten 15 Jahren sehr deutlich gesunken sind, ist der Einsatz durch Akzeptanzprobleme in der Landwirtschaft und bei der Nahrungsmittelindustrie limitiert. Es gilt deshalb, Entsorgungspfade aufzubauen, die eine mittel- und langfristige Sicherung der Entsorgung ermoeglichen. Nach den neueren Anforderungen an eine Deponierung ist demnach immer eine Verbrennung vorzusehen. Die z.Z. noch geltende Uebergangsregelung hat zu massiven Reaktionen des Entsorgungsmarktes gefuehrt. Die Planungen zur Klaerschlammentsorgung muessen sich an den Grundsaetzen der Umsetzbarkeit und betrieblichen Handhabbarkeit ausrichten. (orig.)

  9. 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.

  10. Studies on land application of sewage sludge and its limiting factors

    International Nuclear Information System (INIS)

    Wang Xin; Chen Tao; Ge Yinghua; Jia Yongfeng

    2008-01-01

    Field experiments were conducted to study the effect of sewage sludge application on the heavy metal content in soils and grasses. The sewage sludge was obtained from Northern Shenyang Wastewater Treatment Plant, China, and applied at 0, 15, 30, 60, 120 and 150 t ha -1 . Native grasses Zoysia japonica and Poa annua were chosen as experimental plants. The experimental results showed that nutrient content of the soil, especially organic matter, was increased after sewage sludge application. The grass biomass was increased and the grass growing season was longer. Heavy metal concentrations in the soil also increased; however, the Zn content did not exceed the stringent Chinese environmental quality standard for soil. Pb and Cu did not exceed the standard for B grade soil, but Cd concentration in soil amended by sewage sludge has exceeded the B grade standard. Therefore, it is suggested that the sewage sludge produced from the wastewater treatment plant should not be applied to farmland, for which B grade soil or better is required. The sludge is suitable for application to forestry and grasslands or nurseries where food chain contamination with cadmium is not a concern

  11. Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece

    Energy Technology Data Exchange (ETDEWEB)

    Samolada, M.C. [Dept. Secretariat of Environmental and Urban Planning – Decentralized Area Macedonian Thrace, Taki Oikonomidi 1, 54008 Thessaloniki (Greece); Zabaniotou, A.A., E-mail: azampani@auth.gr [Aristotle University of Thessaloniki, Dept. of Chemical Engineering, University Box 455, University Campus, 541 24 Thessaloniki (Greece)

    2014-02-15

    Highlights: • The high output of MSS highlights the need for alternative routes of valorization. • Evaluation of 3 sludge-to-energy valorisation methods through SWOT analysis. • Pyrolysis is an energy and material recovery process resulting to ‘zero waste’. • Identification of challenges and barriers for MSS pyrolysis in Greece was investigated. • Adopters of pyrolysis systems face the challenge of finding new product markets. - Abstract: For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a ‘zero waste’ solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated.

  12. Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece

    International Nuclear Information System (INIS)

    Samolada, M.C.; Zabaniotou, A.A.

    2014-01-01

    Highlights: • The high output of MSS highlights the need for alternative routes of valorization. • Evaluation of 3 sludge-to-energy valorisation methods through SWOT analysis. • Pyrolysis is an energy and material recovery process resulting to ‘zero waste’. • Identification of challenges and barriers for MSS pyrolysis in Greece was investigated. • Adopters of pyrolysis systems face the challenge of finding new product markets. - Abstract: For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a ‘zero waste’ solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated

  13. Essential oil production of lemongrass (Cymbopogon citratus under organic compost containing sewage sludge

    Directory of Open Access Journals (Sweden)

    Júlia V. d'Ávila

    Full Text Available ABSTRACT One of the main urban polluting agents are the sewers, which even with proper treatment end up generating a polluting waste, the sewage sludge. One of the options for the disposal of this sludge is the use in agriculture, due to its high content of organic matter and nutrients. This study aimed to use urban sewage sludge for lemongrass cultivation and essential oil production. The plants were grown in soil containing different organic compost doses (0, 5, 10, 20, 40 and 60 t ha-1, formed from the sewage sludge composting process and waste of urban vegetation pruning. At harvest, plants were analyzed for the concentration of nutrients, chlorophyll content, number of tillers, biomass production, essential oil content and the microbiological quality of the leaves. The results showed that the addition of the compost increased the levels of nutrients in the plants, mainly nitrogen, positively influencing the production of tillers, biomass, chlorophyll contents, yield and essential oil content.

  14. Assessment of doses due to radionuclides in sewage sludge for different scenario of its use

    International Nuclear Information System (INIS)

    Lydagiene, R.; Morkunas, G.; Pilkyte, L.

    2003-01-01

    Assessment of doses due to radionuclides in sewage sludge for different scenarios of its use was made for sewage plant storage in Visaginas, Rimses district, Karlu village. Calculations of individual and collective doses were made on the basis of results of measurements. Two potential exposure pathways from radionuclides in sewage sludge were considered and two scenarios descriptions were made. The first scenario is when the sludge is using for fertilization, and the second one - the sludge is covered with soil. Using program Environ-Calc made by American Chemical Society the number of samples needed to be sampled was optimized. 38 sewage samples were collected for gamma spectrometrical measurements and 10 samples - for measurements of tritium activity. Results of measurements pointed out that the sludge has no higher activity of tritium that background ones. The only two man made radionuclides 60 Co and 137 Cs were found by gamma spectrometry in the sludge. Average activity for the fresh weight in the samples of 60 Co was 42 Bq/kg, 137 Cs - 10 Bq/kg. Concentration of natural radionuclides was in the same range as in any soil samples from Lithuania. The dose for the first scenario for 1 years child will be 12 μSv, for adult - 9,4 μSv. In another scenario doses for the workers in sewage plant were estimated as 0,76 mSv. Collective dose in case of use of sewage sludge for fertilizers will be 4,4*10 -3 man Sv. The lowest doses will be when the sewage storage is covered using soil. (author)

  15. The pilot plant in Geiselbullach for the gamma irradiation of sewage sludge - design, operation experience and cost calculations

    International Nuclear Information System (INIS)

    Lessel, T.; Hennig, E.

    1976-01-01

    Gamma irradiation of sewage sludge is possible with facilities of simple design and great availability; they can be working fully automatically 24 hours on 350 days a year or more. No specially trained service staff is necessary. The costs for gamma irradiation of sewage sludge are slightly higher than for heat treatment, but several secondary effects speak in favour of the irradiated sludge. The hygienization of sewage sludge by gamma irradiation is normally only useful when sludge has to be disinfected during the whole year. (orig.) [de

  16. Polybrominated diphenyl ethers in sewage sludge from Shanghai, China: possible ecological risk applied to agricultural land.

    Science.gov (United States)

    Yang, Chao; Meng, Xiang-Zhou; Chen, Ling; Xia, Siqing

    2011-10-01

    Ideally, agricultural use is a treatment for the sewage sludge generated from municipal wastewater. However, this treatment probably causes ecological risks due to the occurrence of organic contaminants in sludge, which has attracted rising concerns recently. To assess the possible ecological risk, in this study, sewage sludge samples were collected from 28 wastewater treatment plants (WWTPs) in Shanghai, China for exploring the level and profile of polybrominated diphenyl ethers (PBDEs). The mean concentration of Σ18PBDE (sum of all target analytes except for BDE-209) was at the low end of global range. However, we found the highest reported BDE-209 levels (34,900 ng g(-1) dw) in sewage sludge/biosoilds to date. The annual mass loadings of penta-BDE, octa-BDE, and deca-BDE were 3.6, 0.6, and 763 kg through sludge, respectively. Following sludge application in agricultural land, the concentrations of penta-BDE, octa-BDE, and deca-BDE in soil were 0.19, 0.03, and 39.5 ng g(-1), respectively. Preliminary results indicate that the ecological risk of soil in organisms exposed to PBDEs was relatively low. Nevertheless, further studies are needed to explore the fate of PBDEs in sewage sludge due to no restriction on the usage and production of PBDEs products in China currently. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Co-Combustion of Municipal Sewage Sludge and Hard Coal on Fluidized Bed Boiler WF-6

    Directory of Open Access Journals (Sweden)

    Rajczyk Rafał

    2014-12-01

    Full Text Available According to data of the Central Statistical Office, the amount of sludge produced in municipal wastewater treatment plants in 2010 amounted to 526000 Mg d.m. The forecast of municipal sewage sludge amount in 2015 according to KPGO2014 will reach 642400 Mg d.m. and is expected to increase in subsequent years. Significant amounts of sludge will create problems due to its utilization. In order to solve this problem the use of thermal methods for sludge utilization is expected. According to the National Waste Management Plan nearly 30% of sewage sludge mass should be thermally utilized by 2022. The article presents the results of co-combustion of coal and municipal sewage sludge in a bubbling fluidized bed boiler made by SEFAKO and located in the Municipal Heating Company in Morag. Four tests of hard coal and sewage sludge co-combustion have been conducted. Boiler performance, emissions and ash quality were investigated.

  18. Potential harmful effects on agricultural environments of sewage sludge utilization as a fertilizer

    International Nuclear Information System (INIS)

    Suess, A.

    1997-01-01

    There can be harmful effects of sewage-sludge utilization in agriculture. However, these can be overcome by treatment of the sludge and by appropriate farm-management practices. Sewage sludge is of increasing potential importance to farmers because of its value as a fertilizer. But some compounds in sludge can be harmful for plants, animals and man. Heavy metals may be taken up by plants, and the higher the content in the soil, the greater the uptake. There are substantial differences in heavy-metal accumulation and tolerance among plant species. With respect to pathogens (for example Salmonella) in sludge, recent developments in decontamination processes can provide greater guarantee of preservation of the environment. Gamma-radiation treatment at a dose of 3 kGy has been proven effective. The use of sewage sludge in agriculture is attractive from the economical and environmental points of view. It is therefore important that farmers are provided not only with more information about the nutrient effects, but also about risks, if any, of leaching of heavy metals and microbial condition to groundwater. To achieve this, there must be close co-operation between farmers and the authorities responsible for disposal of sewage sludge. (author)

  19. The Different Physiological and Antioxidative Responses of Zucchini and Cucumber to Sewage Sludge Application.

    Directory of Open Access Journals (Sweden)

    Anna Wyrwicka

    Full Text Available The present study investigates the effect of soil amended with sewage sludge on oxidative changes in zucchini and cucumber plants (Cucurbitaceae and the consequent activation of their antioxidative systems and detoxification mechanisms. The plants were grown in pots containing soil amended with three concentrations of sewage sludge (1.8 g, 5.4 g and 10.8 g per pot, while controls were potted with vegetable soil. The activities of three antioxidative enzymes, ascorbate peroxidase (APx, catalase (CAT and guaiacol peroxidase (POx, were assessed, as well as of the detoxifying enzyme S-glutathione transferase (GST. Lipid peroxidation was evaluated by measuring the extent of oxidative damage; α-tocopherol content, the main lipophilic antioxidant, was also measured. Visible symptoms of leaf blade damage after sewage sludge application occurred only on the zucchini plants. The zucchini and cucumber plants showed a range of enzymatic antioxidant responses to sewage sludge application. While APx and POx activities increased significantly with increasing sludge concentration in the zucchini plants, they decreased in the cucumber plants. Moreover, although the activity of these enzymes increased gradually with increasing doses of sewage sludge, these levels fell at the highest dose. An inverse relationship between peroxidases activity and CAT activity was observed in both investigated plant species. In contrast, although GST activity increased progressively with sludge concentration in both the zucchini and cucumber leaves, the increase in GST activity was greater in the zucchini plants, being visible at the lowest dose used. The results indicate that signs of sewage sludge toxicity were greater in zucchini than cucumber, and its defense reactions were mainly associated with increases in APx, POx and GST activity.

  20. Improving material and energy recovery from the sewage sludge and biomass residues.

    Science.gov (United States)

    Kliopova, Irina; Makarskienė, Kristina

    2015-02-01

    Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives of sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10-40 mm) of pre-composted materials--sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg(-1) of the net calorific value, about 23% were composted, the rest--evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning, comparison analysis with widely used bio-fuel-sawdust and conclusions made are presented. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. The Different Physiological and Antioxidative Responses of Zucchini and Cucumber to Sewage Sludge Application.

    Science.gov (United States)

    Wyrwicka, Anna; Urbaniak, Magdalena

    2016-01-01

    The present study investigates the effect of soil amended with sewage sludge on oxidative changes in zucchini and cucumber plants (Cucurbitaceae) and the consequent activation of their antioxidative systems and detoxification mechanisms. The plants were grown in pots containing soil amended with three concentrations of sewage sludge (1.8 g, 5.4 g and 10.8 g per pot), while controls were potted with vegetable soil. The activities of three antioxidative enzymes, ascorbate peroxidase (APx), catalase (CAT) and guaiacol peroxidase (POx), were assessed, as well as of the detoxifying enzyme S-glutathione transferase (GST). Lipid peroxidation was evaluated by measuring the extent of oxidative damage; α-tocopherol content, the main lipophilic antioxidant, was also measured. Visible symptoms of leaf blade damage after sewage sludge application occurred only on the zucchini plants. The zucchini and cucumber plants showed a range of enzymatic antioxidant responses to sewage sludge application. While APx and POx activities increased significantly with increasing sludge concentration in the zucchini plants, they decreased in the cucumber plants. Moreover, although the activity of these enzymes increased gradually with increasing doses of sewage sludge, these levels fell at the highest dose. An inverse relationship between peroxidases activity and CAT activity was observed in both investigated plant species. In contrast, although GST activity increased progressively with sludge concentration in both the zucchini and cucumber leaves, the increase in GST activity was greater in the zucchini plants, being visible at the lowest dose used. The results indicate that signs of sewage sludge toxicity were greater in zucchini than cucumber, and its defense reactions were mainly associated with increases in APx, POx and GST activity.

  2. Disinfection of sewage water and sludge using gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Musaad, R M.A. [Department of Radiation Chemistry, Atomic Energy Research Coordination Council, Sudan Academy of Sciences, Khartoum (Sudan)

    2008-04-15

    This study has been carried out to assess the efficiency of gamma radiation in disinfecting sewage water and sludge from harmful pathogenic bacteria (e.g. Streptococcus, Salmonella, Shigella, total E-coli and total coliform), parasites (Ascaris ova) as well as its ability to degrade organic matter (BOD). Samples were exposed to gamma-radiation doses ranging from 0.5 to 8 KGy using Co''6{sup 0} cell. Amongst pathogenic bacteria which are subjected to different doses of gamma-radiation Streptococcus faecalis revealed to be the most resistance bacterial indicator since complete elimination of these bacteria could be attained at 3.5 KGy. While total e-coli shown to be the most sensitive with lethal dose at 2 KGy. The radiation doses that required for reducing the bacterial population by 90% (D{sub 10}) and 50% (D {sub 50}) were determined for each species. The D{sub 10} values found ranged from 0.75 KGy for Streptococcus and 2.75 KGy for total count bacteria. On the other hand, D{sub 50} fall within the range of 0.5 KGy for total count bacteria, total coliform and Streptococcus, and 1.0 KGy for total e-coli. With regard to the efficiency of radiation treatment to destroy Ascaris ova viability it was found that no larvae were viable after exposure to 1.0 KGy following incubation of exposed ova for four weeks period.(Author)

  3. Disinfection of sewage water and sludge using gamma radiation

    International Nuclear Information System (INIS)

    Musaad, R.M.A.

    2008-04-01

    This study has been carried out to assess the efficiency of gamma radiation in disinfecting sewage water and sludge from harmful pathogenic bacteria (e.g. Streptococcus, Salmonella, Shigella, total E-coli and total coliform), parasites (Ascaris ova) as well as its ability to degrade organic matter (BOD). Samples were exposed to gamma-radiation doses ranging from 0.5 to 8 KGy using Co''6 0 cell. Amongst pathogenic bacteria which are subjected to different doses of gamma-radiation Streptococcus faecalis revealed to be the most resistance bacterial indicator since complete elimination of these bacteria could be attained at 3.5 KGy. While total e-coli shown to be the most sensitive with lethal dose at 2 KGy. The radiation doses that required for reducing the bacterial population by 90% (D 10 ) and 50% (D 50 ) were determined for each species. The D 10 values found ranged from 0.75 KGy for Streptococcus and 2.75 KGy for total count bacteria. On the other hand, D 50 fall within the range of 0.5 KGy for total count bacteria, total coliform and Streptococcus, and 1.0 KGy for total e-coli. With regard to the efficiency of radiation treatment to destroy Ascaris ova viability it was found that no larvae were viable after exposure to 1.0 KGy following incubation of exposed ova for four weeks period.(Author)

  4. Zinc, copper and manganese availability in soils treated with alkaline sewage sludge from Paraná state (Brazil

    Directory of Open Access Journals (Sweden)

    Maristela Dalpisol

    Full Text Available ABSTRACT In Paraná, most of the sludge generated in sewage treatment plants is subjected to the prolonged alkaline stabilization process. Although it is known that the alkaline sewage sludge contains micronutrients such as Zn, Cu and Mn, little is known about the availability of these elements in soils treated with this type of sewage sludge. Thus, the objective of the study was to evaluate the influence of alkaline sewage sludge from Paraná on Zn, Cu and Mn availability in soils. Twenty sewage treatment plants were selected throughout Paraná, where alkaline sewage sludge and the most representative agricultural soil of the each region were collected. Each soil was incubated for 60 days with alkaline sewage sludge rates (0, 10, 20, 40, and 80 Mg ha-1 from their region. Subsequently, Zn, Cu and Mn availability was determined using the Mehlich-1 extractant. The alkaline sewage sludge increased Zn availability and decreased Mn availability in most soils. Cu showed intermediate results, with increased availability, primarily in medium texture soils and decrease in most of the clayey soils. In soils with pH close to ideal for the plant growth, the alkaline sewage sludge rate should be carefully calculated so that there is no excessive increase in the pH and Zn, Cu and Mn imbalance.

  5. The influence of the anaerobic digestion process on the sewage sludges rheological behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, P.S. [Porto Univ. (Portugal). Facultade de Engenharia. Inst. de Hidraulica e Recursos Hidricos

    1998-12-31

    During the anaerobic digestion process, a significant part of the organic matter is sewage sludge is decomposed to form other organic and inorganic compounds in dissolved form. The biological transformation of a substantial part of the organic solids has, certainly, a strong influence on the rheological characteristics of the sludges. In this paper a test facility was set up to simulate sewage sludge digestion and periodic observations on the evolution of the sludge characteristics were carried out. Results of this study show that important changes on the sludge rheological behaviour occur during anaerobic digestion and that the evolution of those changes is related with the degree of digestion. Moreover, it is shown that the verified high degree of physical changes can not be demonstrated only by the total solids concentration variation and two hypothesis are proposed to explain those changes.

  6. Chemical fractionation of heavy metals in a soil amended with repeated sewage sludge application

    International Nuclear Information System (INIS)

    Walter, I.; Cuevas, G.

    1999-01-01

    A sequential extraction method (KNO 3 , NaOH, Na 2 -EDTA, HNO 3 ) was used to determine the soil fraction of Zn, Cd, Cu, Ni, Pb, and Cr in different plots treated with sewage sludges. The sludges were applied to cropland from 1983 to 1991. Soil samples were collected after the 1st and 5th-year of the last sludge application. Sludge applications increased the INOR-fraction for Zn, Cd, and Cu. Cu was the only element found in the EXCH-fraction. Pb and Cr were found mainly in the RES-fraction. Ni was found in the INOR and OM-fractions. All the metals increased in the more resistant fractions. Sewage sludge applications changed the metals distribution of the soil and this effect has continued for at least 5 years. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Survey in organic contaminants content in sewage sludge from the Emilia Romagna region

    International Nuclear Information System (INIS)

    Mantovi, P.; Sassi, D.; Piccinini, S.; Rossi, L.

    2008-01-01

    Data was collected on the organic pollutants cited in the Working document on sludge, 3. draft (AOX, LAS, DEHP, NPE, PAH, PCB, PCDD/F), for sewage sludge deriving from 12 municipal-industrial wastewater treatment plants and 7 agro-industrial wastewater treatment plants located in the Emilia-Romagna region (Italy), taking samples in spring, summer and winter. The limit values given in the Working document were sporadically exceeded. The most frequent contamination was associated with LAS, in particular in the winter period. Results confirmed lower organic contaminant contents in sludge of agro-industrial origin, compared to sludge from municipal-industrial wastewater treatment plants, with generally not detectable values for the majority of organic pollutants. Comparison of the results collected in this survey with values recorded in other European countries shows that the organic contaminant content of sewage sludge obtained in plants in the Emilia-Romagna region, excepting LAS, is reasonable [it

  8. Metal concentrations in earthworms from sewage sludge-amended soils at a strip mine reclamation site

    Energy Technology Data Exchange (ETDEWEB)

    Pietz, R.I.; Peterson, J.R.; Prater, J.E.; Zenz, D.R.

    A 3-yr study of earthworms was initiated in selected mine soil and nonmined fields at a Fulton County, IL land reclamation site. The purpose of this research was to determine the effect of the land application of anaerobically digested sewage sludge, used to reclaim the site, on heavy metal accumulations in earthworms. Two species of earthworms, Lumbricus terrestris and Aporrectodea tuberculata, were identified in the sludge-amended and nonamended, nonmined fields sampled. Only A. tuberculata was found in the sludge-amended and nonamended mine soil fields sampled. Earthworm metal concentrations generally increased with time in all the sampled fields. The decreasing order of metal accumulation by earthworms in all sludge-amended fields sampled was Cu > Cd > Ni > Cr > Pb > Zn. Sewage sludge applications to fields on both land types resulted in significant accumulations of Cd, Cu, and Zn. Land type (mine soil vs. nonmined) significantly affected earthworm Zn concentrations, with levels being higher in all nonmined fields sampled. Earthworm Cd and Cu accumulations in all fields sampled were significantly related to the current amounts of sludge-applied metals, the amount applied since the previous sampling. Concentrations of Ni, Cr, and Pb in earthworms were not significantly related to sewage sludge applications during the 1975 to 1977 sampling period. The higher Cd and Cu concentrations in earthworms from sludge-amended fields may pose a potential hazard to predators.

  9. Utilization of municipal sewage sludge as additives for the production of eco-cement

    International Nuclear Information System (INIS)

    Lin, Yiming; Zhou, Shaoqi; Li, Fuzhen; Lin, Yixiao

    2012-01-01

    Highlights: ► The results of X-ray diffraction (XRD) pattern and scanning electron micrograph (SEM) indicated that the major components in the eco-cement clinkers were similar to those in ordinary Portland cement. ► Though the C 2 S phase formation increased with the increase of sewage sludge contents. ► All the eco-cement pastes had a longer initial setting time and final setting time than those of plain cement paste, which increased as the sewage sludge contents in raw meal increased. ► All the eco-cement pastes had lower early flexural strengths and it increased with the increase of sewage sludge contents increased, while the compressive strengths decreased slightly. ► However, it had no significant effect on all the strengths at later ages. - Abstract: The effects of using dried sewage sludge as additive on cement property in the process of clinker burning were investigated in this paper. The eco-cement samples were prepared by adding 0.50–15.0% of dried sewage sludge to unit raw meal, and then the mixtures were burned at 1450 °C for 2 h. The results indicated that the major components in the eco-cement clinkers were similar to those in ordinary Portland cement. Although the C 2 S phase formation increased with the increase of sewage sludge content, it was also found that the microstructure of the mixture containing 15.0% sewage sludge in raw meal was significantly different and that a larger amount of pores were distributed in the clinker. Moreover, all the eco-cement pastes had a longer initial setting time and final setting time than those of plain cement paste, which increased as the sewage sludge content in the raw meal increased. All the eco-cement pastes had lower early flexural strengths, which increased as the sewage sludge content increased, while the compressive strengths decreased slightly. However, this had no significant effect on all the strengths at later stages. Furthermore, the leaching concentrations of all the types of eco

  10. Attributes of the soil fertilized with sewage sludge and calcium and magnesium silicate

    Directory of Open Access Journals (Sweden)

    Geraldo R. Zuba Junio

    2015-11-01

    Full Text Available ABSTRACTThis study aimed to evaluate the chemical attributes of an Inceptisol cultivated with castor bean (Ricinus communis L., variety ‘BRS Energia’, fertilized with sewage sludge compost and calcium (Ca and magnesium (Mg silicate. The experiment was conducted at the ICA/UFMG, in a randomized block design, using a 2 x 4 factorial scheme with three replicates, and the treatments consisted of two doses of Ca-Mg silicate (0 and 1 t ha-1 and four doses of sewage sludge compost (0, 23.81, 47.62 and 71.43 t ha-1, on dry basis. Soil organic matter (OM, pH, sum of bases (SB, effective cation exchange capacity (CEC(t, total cation exchange capacity (CEC(T, base saturation (V% and potential acidity (H + Al were evaluated. There were no significant interactions between doses of sewage sludge compost and doses of Ca-Mg silicate on soil attributes, and no effect of silicate fertilization on these attributes. However, fertilization with sewage sludge compost promoted reduction in pH and increase in H + Al, OM and CEC. The dose of 71.43 t ha-1 of sewage sludge compost promoted the best soil chemical conditions.

  11. Radioresistance of microorganisms in sewage sludge with special regard to the virus species

    International Nuclear Information System (INIS)

    Mayr, A.; Mahnel, H.; Brodorotti, H.S. v.; Ottis, K.

    1979-01-01

    Of the viral species present in surface and waste water only entero-, reo-, parvo-, and possibly paramyxoviruses are of relevance. These viruses remain infectious through to the sewage sludge stage, although then only present in small numbers. Bacteria and moulds are present in high concentrations in sewage sludge, the majority being non-pathogenis or only facultative pathogenic species. Of these only Salmonellae are of public health concern. Viruses are considerably more radiation resistant than bacteria and moulds. In sewage sludge a parvo virus was clearly the most resistant towards radiation followed, in order of decreasing resistivity, by reo- and entero-viruses. With the exception of the strongly resistant streptococcus faecalis two enterobacteria and one mould were found to be relatively radiation-sensitive. Gamma radiation is effective for inactivating all viral and bacterial contamination of sewage sludge. The dose required depends upon the radiation resistance and concentration of the individual strain. Enteroviral elimination determines the dose required for viruses and salmonella radiation the dose for bacteria. For practical sewage sludge decontamination a total irradiation dose of 500 krad has been calculated to meet normal requirements, and this dose can be raised to 1 Mrad for more stringent demands. (orig./MG) [de

  12. Analysis of briquetting process of sewage sludge with coal to combustion process

    Directory of Open Access Journals (Sweden)

    Kosturkiewicz Bogdan

    2016-01-01

    Full Text Available Energy recovery from sewage sludge can be achieved by several thermal technologies, but before those processes sewage sludge requires special pretreatment. The paper presents the investigation of the sewage sludge with coal briquettes as a fuel for combustion process. Research is conducted at Department of Manufacturing Systems and Department of Thermal Engineering and Environmental Protection, AGH University of Science and Technology to develop a technology of briquette preparation. The obtained results showed possibility of briquetting of municipal sewage sludge with coal in roll presses, equipped with asymmetric thickening gravity feed system. The following properties were determined for the obtained briquettes: density, drop strength and compressive strength. Based on physical and chemical analysis of prepared briquettes it was confirmed that briquettes have good fuel properties to combustion process. Thermal behaviour of studied sewage sludge and prepared mixture was investigated by thermogravimetric analysis (TG. For the thermo gravimetric analysis (TG the samples were heated in an alumina crucible from an ambient temperature up to 1000 °C at a constant rates: 10 °C/min, 40 °C/min and 100 °C/min in a 40 ml/min flow of air.

  13. Disinfection of sewage sludge by gamma radiation, electron beams and alternative methods

    International Nuclear Information System (INIS)

    Lessel, T.

    1997-01-01

    Sewage sludges generally contain high concentrations of pathogens, even after digestion or other conventional treatments for stabilization. Disinfection can be effected by irradiation (e.g. gamma or electron beam), by heat treatment (pasteurization or thermophilic stabilization), and by changing the pH (lime treatment). Irradiation is a simple and reliable process for disinfection with special advantages and favorable side-effects. Irradiation can be combined with oxygenation, heat or other treatments, with favorable synergistic effects. The total costs for the irradiation treatment of sewage sludges are comparable to those of alternative disinfection methods. Most of the worldwide practical experience has been obtained at the sewage-sludge irradiation plant in Geiselbullach (10 km west of Munich, Germany), which was continuously in operation from 1973 to 1993. A multidisciplinary research programme was conducted during the first 8 years. In subsequent years, the plant was operated commercially for sewage-sludge disinfection, without public funds. Other demonstration or research plants for sewage-sludge irradiation have been reported in the USA, India, Russia, Japan, Austria, Germany and Hungary. (author)

  14. Plant growth inhibition by soluble salts in sewage sludge-amended mine spoils

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, C.S.; Anderson, R.C. [Illinois State University, Normal, IL (United States). Dept. of Biological Sciences

    1995-07-01

    The growth response of prairie switchgrass {ital Panicum virgatum}L was compared in strip mine spoil amended with various levels of anaerobically digested waste-activated sewage sludge (0, 56, 111, 222, or 333 dry Mg ha{sup -1}) and commercial fertilizer, pure sludge, and glasshouse soil. Plants were grown in a growth chamber and substrates were maintained at field capacity during the study. Soluble salt concentrations of the substrates increased linearly as a function of sludge amendment and were within the range known to inhibit the growth of many plant species at the high levels of sludge application. There was, however, a linear response of biomass production to increasing levels of sludge amendment. Maintaining substrates at field capacity apparently prevented the high concentration of soluble salts from inhibiting plant growth. The increased biomass yield associated with sludge application was likely due to the increased availability of inorganic nutrients associated with sludge amendment. 22 refs., 2 figs., 2 tabs.

  15. Pharmaceutical load in sewage sludge and biochar produced by hydrothermal carbonization.

    Science.gov (United States)

    vom Eyser, C; Palmu, K; Schmidt, T C; Tuerk, J

    2015-12-15

    We investigated the removal of twelve pharmaceuticals in sewage sludge by hydrothermal carbonization (HTC), which has emerged as a technology for improving the quality of organic waste materials producing a valuable biochar material. In this study, the HTC converted sewage sludge samples to a biochar product within 4h at a temperature of 210 °C and a resulting pressure of about 15 bar. Initial pharmaceutical load of the sewage sludge was investigated as well as the residual concentrations in biochar produced from spiked and eight native sewage sludge samples from three waste water treatment plants. Additionally, the solid contents of source material and product were compared, which showed a considerable increase of the solid content after filtration by HTC. All pharmaceuticals except sulfamethoxazole, which remained below the limit of quantification, frequently occurred in the investigated sewage sludges in the μg/kg dry matter (DM) range. Diclofenac, carbamazepine, metoprolol and propranolol were detected in all sludge samples with a maximum concentration of 800 μg/kgDM for metoprolol. HTC was investigated regarding its contaminant removal efficiency using spiked sewage sludge. Pharmaceutical concentrations were reduced for seven compounds by 39% (metoprolol) to≥97% (carbamazepine). In native biochar samples the four compounds phenazone, carbamazepine, metoprolol and propranolol were detected, which confirmed that the HTC process can reduce the load of micropollutants. In contrast to the other investigated compounds phenazone concentration increased, which was further addressed in thermal behaviour studies including three structurally similar potential precursors. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Study on dewatering of chemical sludge by freeze-thaw process

    International Nuclear Information System (INIS)

    Xu Shikun; Liu Pin

    1993-01-01

    The treatment of radioactive sludge that is produced from treating radioactive waste water contains radioactively is different from that of non-radioactive sludge. The methods of immersing freeze and simulated two-step freeze have been studied for the elementary properties of simulated low-level radioactive sledge, the effect of freezing temperature, freeze time, and settling time on volume-reduction factor. Some parameters for design of freeze-thaw device are provided

  17. Chemical composition of sewage sludge of domestic and industrial areas of Hyderabad

    International Nuclear Information System (INIS)

    Ansari, T.P.; Kazi, T.G.; Kazi, G.H.

    2001-01-01

    A study on chemical composition sewage sludge of domestic and industrial areas of Hyderabad city has been carried out. The sludge samples were collected from various domestic and industrial areas of Hyderabad, over a period of 3 months. Analysis of sludge samples for different micro-nutrients and toxic elements has been accomplished by reliable analytical methods using atomic absorption, UV and colorimeter. It is observed that the levels of copper, nickel, zinc, lead and cadmium are higher in sludge samples of industrial area than those of domestic areas of Hyderabad. (author)

  18. Influence of gamma-irradiation on the behaviour of sewage sludges

    International Nuclear Information System (INIS)

    Hegeman, W.; Guenthert, W.

    1976-01-01

    Since summer, 1975 the Institute of Water Quality Management and Sanitary Engineering of The Tehnical University Munich has been performing tests on the alterations of the quality and the behaviour of sewage sludge caused by gamma-irradiation at the Geiselbullach treatment facilities. The tests comprise studies of the thickening ability in laboratory scale thickeners (V=30 l) and the determination of the specific resistance to filtration of untreated, pasteurised and irradiated sludges. The concentration of the supernatent liquor is characterised by the measurement of BOD 5 and COD. Test results of the dewaterability of the different sludges in filter presses and the amount of coagulants necessary for sludge conditioning are presented. (author)

  19. Natural attenuation of toxic metal phytoavailability in 35-year-old sewage sludge-amended soil.

    Science.gov (United States)

    Tai, Yiping; Li, Zhian; Mcbride, Murray B

    2016-04-01

    Toxic heavy metals persist in agricultural soils and ecosystem for many decades after their application as contaminants in sewage sludge and fertilizer products This study assessed the potential long-term risk of cadmium (Cd), lead (Pb), zinc (Zn), and copper (Cu) in land-applied sewage sludge to food crop contamination. A sewage sludge-amended soil (SAS) aged in the field more than 35 years was used in a greenhouse pot experiment with leafy vegetables (lettuce and amaranth) having strong Cd and Zn accumulation tendencies. Soil media with variable levels of available Cd, Zn, and Cu (measured using 0.01 M CaCl2 extraction) were prepared by diluting SAS with several levels of uncontaminated control soil. Despite long-term aging in the field, the sludge site soil still retains large reserves of heavy metals, residual organic matter, phosphorus, and other nutrients, but its characteristics appear to have stabilized over time. Nevertheless, lettuce and amaranth harvested from the sludge-treated soil had undesirable contents of Cd and Zn. The high plant uptake efficiency for Cd and Zn raises a concern regarding the quality and safety of leafy vegetables in particular, when these crops are grown on soils that have been amended heavily with sewage sludge products at any time in their past.

  20. Sewage sludge treatment and disposal in Germany. Results of the DWA Sewage Sludge Study of 2003; Stand der Klaerschlammbehandlung und -entsorgung in Deutschland. Ergebnisse der DWA-Klaerschlammerhebung 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-10-15

    In 2003, DWA carried out a nation-wide enquiry on sewage sludge treatment and disposal in Germany among operators of communal sewage treatment plant. Information was obtained on sewage sludge volumes and qualities as well as on methods of treatment and disposal pathways. Data were also compiled on the volumes and disposal of filtered-out material. This publication also includes results of other studies, e.g. by the Federal Office of Statistics (StBA) and Federal Environmental Office (UBA). The studies were initiated by the DWA Waste and Sewage Sludge Section. (orig.)

  1. Environmental application for GIS: Assessing Iskandar Malaysia's (IM) sewage sludge for potential biomass resource

    Science.gov (United States)

    Salim, M. R.; Shaharuddin, N.; Abdullah Halim, K.

    2014-02-01

    The low carbon scenario could be achieved through the identification of major sectors contributing to the emission of high greenhouse gases (GHG) into the atmosphere. Sewage treatment plant (STP) was ranked as one of the major sectors that emits methane gas (CH4) during treatment processes, including sludge treatment. Sludge treatment is also capital extensive with high operational cost. Thus, sewage sludge has been accepted as a nuisance in STP. However, many has claimed that, sludge produced contain organic matter that has the potential for biomass resource. Thus, it would be such a Žwaste? if sludge are directly disposed of into the landfill without utilizing them at its full potential. In order to do so, it is vital to be able to determine the amount of sludge production. This research was implemented in Iskandar Malaysia regions in the state of Johor. By using GIS tool, the regions that produced the most sewage sludge can be determined, and can be group as critical area. Result shows that Nusajaya produces the most, compared to other regions, which indicated Nusajaya as a densely populated region.

  2. The kinetics of combustion of chars derived from sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    J.S. Dennis; R.J. Lambert; A.J. Milne; S.A. Scott; A.N. Hayhurst [University of Cambridge, Cambridge (United Kingdom). Department of Chemical Engineering

    2005-02-01

    Experiments have been conducted to determine the combustion characteristics of sewage sludge chars in electrically heated beds of silica sand fluidised by air. The effects of the initial size of the char particles, the temperature of the bed and the concentration of (O{sub 2}) in the fluidising gas were investigated. Also, the temperatures of burning particles were measured with embedded thermocouples. The kinetics of combustion were measured at temperatures low enough for the CO formed by initial reaction between the carbon and oxygen to burn at some distance away from the particle. It is probable that the lower value is closer to the actual value, thought to be 135{+-}15 kJ/mol, reflecting the catalytic nature of the ash skeleton on which the carbon is supported. It was possible to obtain good agreement between measured burnout times and those predicted using the grain model of Szekely J, Evans JW, Sohn HY. Gas-solid reactions. New York: Academic Press; 1976, for the case where the kinetics are controlled by a combination of: (i) external mass transfer of oxygen from the particulate phase to the external surface of the burning char particle, (ii) diffusion of oxygen from the external surface into the porous matrix to the surfaces of grains, of which the solid is composed, and (iii) diffusion of oxygen into the microporous grains, where reaction occurs with the carbon. It was found that, for particles with diameters of 2 mm or larger, the initial rates of reaction, for bed temperatures in excess of 750{degree}C, are dominated by external mass transfer. 22 refs., 8 figs., 1 tab.

  3. Management of sewage sludge by composting using fermented water hyacinth.

    Science.gov (United States)

    Tello-Andrade, A F; Jiménez-Moleón, M C; Sánchez-Galván, G

    2015-10-01

    The goal of the present research work was to assess the management of sewage sludge (SS) by composting using fermented water hyacinth (WHferm) as an amendment. The water hyacinth was fermented, and a higher production of volatile fatty acids (VFAs) (782.67 mg L(-1)) and soluble organic carbon (CSOL) (4788.34 mg L(-1)) was obtained using a particle size of 7 mm compared to 50 mm. For composting, four treatments (10 kg fresh weight each) were evaluated: treatment A (100 % SS + 0 % WHferm), treatment B (75 % SS + 25 % WHferm), treatment C (50 % SS + 50 % WHferm), and treatment D (25 % SS + 75 % WHferm). The WHferm added to SS, especially in treatments C (50 %) and D (75 %), increased the initial contents of organic matter (OM), organic carbon (CORG), CSOL, the C/N ratio, and the germination index (GI). The heavy metal content (HMC) (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) at the beginning was below the maximum allowed by USEPA regulations. All of the samples were free of Salmonella sp. from the beginning. The reduction of the CORG, CSOL, total Kjeldahl nitrogen (TKN), and C/N ratio indicated the degradation of the OM by day 198. The treatments with WHferm (B, C, and D) yielded higher values of electrical conductivity, cation exchange capacity, and GI than SS at day 198. No significant differences were observed in GI among the treatments with WHferm. The fecal coliforms were eliminated (Penicillium, Rhizopus, Paecilomyces (penicillin producers), and Fusariella isolated from the compost may have promoted the elimination of pathogens since no thermophile temperatures were obtained. WHferm as an amendment in the composting of SS improved the characteristics of the final product, especially when it was used in proportions of 25 and 50 %. An excellent product was obtained in terms of HMC, and the product was B class in terms of pathogens.

  4. Composting sewage sludge with green waste from tree pruning

    Directory of Open Access Journals (Sweden)

    Sarah Mello Leite Moretti

    2015-10-01

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

  5. Moisture variation associated with water input and evaporation during sewage sludge bio-drying.

    Science.gov (United States)

    Cai, Lu; Gao, Ding; Chen, Tong-Bin; Liu, Hong-Tao; Zheng, Guo-Di; Yang, Qi-Wei

    2012-08-01

    The variation of moisture during sewage sludge bio-drying was investigated. In situ measurements were conducted to monitor the bulk moisture and water vapor, while the moisture content, water generation, water evaporation and aeration water input of the bio-drying bulk were calculated based on the water mass balance. The moisture in the sewage sludge bio-drying material decreased from 66% to 54% in response to control technology for bio-drying. During the temperature increasing and thermophilic phases of sewage sludge bio-drying, the moisture content, water generation and water evaporation of the bulk initially increased and then decreased. The peak water generation and evaporation occurred during the thermophilic phase. During the bio-drying, water evaporation was much greater than water generation, and aeration facilitated the water evaporation. Copyright © 2012. Published by Elsevier Ltd.

  6. Life cycle assessment of alternative sewage sludge disposal methods; Oekobilanz von Klaerschlammentsorgungsalternativen

    Energy Technology Data Exchange (ETDEWEB)

    Fehrenbach, H. [Institut fuer Energie- und Umweltforschung (ifeu), Heidelberg (Germany)

    1994-10-01

    At present there are three principal options for sewage sludge disposal in use or under discussion: agricultural utilisation - landfilling - cold pretreatment prior to disposal or utilisation (e.g., composting or fermentation) - thermal pretreatment prior to disposal or utilisation (e.g., monocombustion, co-combustion, pyrolysis, gasification). 10% of sewage sludge is currently combusted, 60% is landfilled, and 30% is used for agriculture. The ifeu Institute has carried out several studies which examine and compare the environmental impact of sewage sludge disposal options. [Deutsch] Zur Entsorgung bzw. Verwertung von Klaerschlamm stehen derzeit drei grundsaetzliche Optionen in Anwendung oder werden diskutiert: - Landwirtschaftliche Verwertung - Deponierung - kalte Vorbehandlung vor Deponierung oder Verwertung (z.B. Kompostierung oder Vergaerung) - thermische Vorbehandlung vorn Deponierung oder Verwertung (z.B. Mono- oder Mitverbrennung, Pyrolyse, Vergasung). Verbrannt werden gegenwaertig etwa 10%, 60% deponiert und 30% landwirschaftlich verwertet. Das ifeu-Institut hat in verschiedenen Arbeiten die Umweltauswirkungen von Klaerschlammentsorgungsoptionen untersucht und gegenuebergestellt. (orig./SR)

  7. Comparison of phosphorus recovery from incineration and gasification sewage sludge ash

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    Incineration of sewage sludge is a common practice in many western countries. Gasification is an attractive option because of its high energy efficiency and flexibility in the usage of the produced gas. However, they both unavoidably produce sewage sludge ash (SSA), a material which is rich...... in phosphorus (P), but that it is commonly landfilled or used in construction materials. With current uncertainty in phosphate rock (PR) supply, P recovery from SSA has become interesting. In the present work, ashes from incineration and gasification of the same sewage sludge were compared in terms of P...... extractability using electrodialytic (ED) methods. The results show that comparable recovery rates of P were achieved with a single ED step for incineration SSA and a sequential combination of two ED steps for gasification SSA, which was due to a higher influence of Fe and/or Al in P solubility for the latter...

  8. Comparison of phosphorus recovery from incineration and gasification sewage sludge ash

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2017-01-01

    Incineration of sewage sludge is a common practice in many western countries. Gasification is an attractive option because of its high energy efficiency and flexibility in the usage of the produced gas. However, they both unavoidably produce sewage sludge ash (SSA), a material which is rich...... in phosphorus (P), but that it is commonly landfilled or used in construction materials. With current uncertainty in phosphate rock (PR) supply, P recovery from SSA has become interesting. In the present work, ashes from incineration and gasification of the same sewage sludge were compared in terms of P...... extractability using electrodialytic (ED) methods. The results show that comparable recovery rates of P were achieved with a single ED step for incineration SSA and a sequential combination of two ED steps for gasification SSA, which was due to a higher influence of Fe and/or Al in P solubility for the latter...

  9. Review of enhanced processes for anaerobic digestion treatment of sewage sludge

    Science.gov (United States)

    Liu, Xinyuan; Han, Zeyu; Yang, Jie; Ye, Tianyi; Yang, Fang; Wu, Nan; Bao, Zhenbo

    2018-02-01

    Great amount of sewage sludge had been produced each year, which led to serious environmental pollution. Many new technologies had been developed recently, but they were hard to be applied in large scales. As one of the traditional technologies, anaerobic fermentation process was capable of obtaining bioenergy by biogas production under the functions of microbes. However, the anaerobic process is facing new challenges due to the low fermentation efficiency caused by the characteristics of sewage sludge itself. In order to improve the energy yield, the enhancement technologies including sewage sludge pretreatment process, co-digestion process, high-solid digestion process and two-stage fermentation process were widely studied in the literatures, which were introduced in this article.

  10. Influence of maize straw content with sewage sludge on composting process

    Directory of Open Access Journals (Sweden)

    Czekała Wojciech

    2016-09-01

    Full Text Available After entrance to EU in 2004, the management of sewage sludge has become more and more important problem for the new members. In Poland, one of the most promising technologies is composting process of sewage sludge with carbonaceous materials. However, the high price of typically used cereal straw forces the specialists to look for new and cheap materials used as donor of carbon and substrates creating good, porous structure of composted heap. This work presents the results of sewage sludge composting mixed with sawdust and maize straw used to create structure favorable for air exchange. The results show dynamic thermophilic phase of composting process in all cases where maize straw was used.

  11. Parametric effect during power generation from sewage sludge using prototype mfc

    International Nuclear Information System (INIS)

    Memon, A.R.; Aftab, A.

    2015-01-01

    Pakistan like other countries is also faced with energy crisis, for which there is a need to identify indigenous technologies along with renewable energy sources to satisfy the energy footprint of the country. Use of MFC (Microbial Fuel Cell) technique is currently a step towards this direction that can play an effective role in solving the dual problems of environmental pollution and energy shortage. In this study, sewage sludge from a wastewater treatment plant was collected and used as a substrate for electricity generation in association with other biomass sources. Effect of relevant parameters such as oxygen flow rate, pH and concentration on voltage generation was also analyzed. The experimental results yielded in voltage generation of 2500 mv/l for sewage sludge in comparison to that obtained using carbon manure (270 mv/l), wastewater (229 mv/l) and cow manure (330 mv/l) suggesting towards the potential of sewage sludge for power generation. (author)

  12. Effect Of Wood-Based Biochar And Sewage Sludge Amendments For Soil Phosphorus Availability

    Directory of Open Access Journals (Sweden)

    Frišták Vladimír

    2015-06-01

    Full Text Available This study investigated the effects of two biochars (pyrolysed wood chips and garden clippings on phosphorus (P availability in a heavy-metal contaminated soil poor in phosphorus. Short-term 14-days incubation experiments were conducted to study how applications of biochars at different rates (1 and 5 % in combination with (1:1 and without dried sewage sludge from a municipal waste water treatment plant (WWTP affected the content of soil extractable P. For P-availability analyses deionized water, calcium acetate lactate (CAL, Mehlich 3 and Olsen extraction protocols were applied. In addition, the content of total and mobile forms of potentially toxic heavy metals (PTHM was studied. Application of both biochars caused a significant decrease of PTHM available forms in sewage sludge amended soil samples. The concentration of total and available P increased with higher biochar and sewage sludge application rates.

  13. Chlorinated hydrocarbons and PCBs in field soils, sediments and sewage sludges

    International Nuclear Information System (INIS)

    Schaaf, H.

    1992-01-01

    As requested by the Ministry of Agriculture of the FRG, the 'Verband Deutscher Landwirtschaftlicher Untersuchungs- und Forschungsanstalten (VDLUFA)' built up a data collection over chlorinated hydrocarbons and PCBs in field soils, sediments, sewage sludges. Nearly 70.000 samples were collected and statistically evaluated. The results of these investigations will be described. The major constituents of the chlorinated hydrocarbons generally were Lindane, DDT(total) and HCB. In sewage sludges PCBs could be detected in nearly every sample. The contents of PCBs in field soils are smaller than in sewage sludges. Rather 'high contents', greater than 100-200 μg/kg d.m./organic pollutants, were detected only in 2% of the samples. 7 refs., 5 figs., 2 tabs

  14. CO2 emission from soil after reforestation and application of sewage sludge

    Directory of Open Access Journals (Sweden)

    Janaina Braga Carmo

    2014-09-01

    Full Text Available This study aimed to quantify the carbon dioxide emissions from an Oxisol under degraded pasture located in Sorocaba, São Paulo State, Brazil. The treatments were: sewage sludge (LE, sewage sludge compost (CLE, mineral fertilizer (AM and no fertilization (T0. The experiment was conducted in a completely randomized block design with analysis of the effect of the four treatments (CLE, LE, and AM T0 with four replications. The application of sewage sludge, sewage sludge compost, mineral fertilizer and no fertilizer was statistically significant for the variables of height increase and stem height of Guanandi seedlings (Calophyllum brasiliense Cambessèdes - Calophyllaceae. Treatments showed significant differences in terms of CO2 emissions from soil. The CLE exhibited the highest CO2 fluxes, reaching a peak of 9.33±0.96 g C m- 2 day- 1 (p<0.0001, as well as the LE with a maximum CO2 flux of 6.35±1.17 C m- 2 day- 1 (p<0.005. The AM treatment (4.96±1.61 g C m- 2 day- 1 had the same statistical effect as T0 (5.33±0.49 g C m- 2 day- 1. CO2 fluxes were correlated with soil temperature in all treatments. However, considering the period of 172 days of evaluation, the total loss of C as CO2 was 2.7% for sewage sludge and 0.7% for the sewage sludge compost of the total C added with the application on soil.

  15. INFLUENCE OF BIOLOGICAL AND THERMAL TRANSFORMED SEWAGE SLUDGE APPLICATION ON MANGANESE CONTENT IN PLANTS AND SOIL

    Directory of Open Access Journals (Sweden)

    Małgorzata Koncewicz-Baran

    2014-10-01

    Full Text Available A great variety of sewage sludge treatment methods, due to the agent (chemical, biological, thermal leads to the formation of varying ‘products’ properties, including the content of heavy metals forms. The aim of the study was to determine the effects of biologically and thermally transformed sewage sludge on the manganese content in plants and form of this element in the soil. The study was based on a two-year pot experiment. In this study was used stabilized sewage sludge collected from Wastewater Treatment Plant Krakow – ”Płaszów” and its mixtures with wheat straw in the gravimetric ratio 1:1 in conversion to material dry matter, transformed biologically (composting by 117 days in a bioreactor and thermally (in the furnace chamber with no air access by the following procedure exposed to temperatures of 130 °C for 40 min → 200 °C for 30 min. In both years of the study biologically and thermally transformed mixtures of sewage sludge with wheat straw demonstrated similar impact on the amount of biomass plants to the pig manure. Bigger amounts of manganese were assessed in oat biomass than in spring rape biomass. The applied sewage sludge and its biologically and thermally converted mixtures did not significantly affect manganese content in plant biomass in comparison with the farmyard manure. The applied fertilization did not modify the values of translocation and bioaccumulation ratios of manganese in the above-ground parts and roots of spring rape and oat. No increase in the content of the available to plants forms of manganese in the soil after applying biologically and thermally transformed sewage sludge mixtures with straw was detected. In the second year, lower contents of these manganese forms were noted in the soil of all objects compared with the first year of the experiment.

  16. Adsorption of mercury by activated carbon prepared from dried sewage sludge in simulated flue gas.

    Science.gov (United States)

    Park, Jeongmin; Lee, Sang-Sup

    2018-04-25

    Conversion of sewage sludge to activated carbon is attractive as an alternative method to ocean dumping for the disposal of sewage sludge. Injection of activated carbon upstream of particulate matter control devices has been suggested as a method to remove elemental mercury from flue gas. Activated carbon was prepared using various activation temperatures and times and was tested for their mercury adsorption efficiency using lab-scale systems. To understand the effect of the physical property of the activated carbon, its mercury adsorption efficiency was investigated as a function of their Brunauer-Emmett-Teller (BET) surface area. Two simulated flue gas conditions: (1) without hydrogen chloride (HCl) and (2) with 20 ppm HCl, were used to investigate the effect of flue gas composition on the mercury adsorption capacity of activated carbon. Despite very low BET surface area of the prepared sewage sludge activated carbons, their mercury adsorption efficiencies were comparable under both simulated flue gas conditions to those of pinewood and coal activated carbons. After injecting HCl into the simulated flue gas, all sewage sludge activated carbons demonstrated high adsorption efficiencies, i.e., more than 87%, regardless of their BET surface area. IMPLICATIONS We tested activated carbons prepared from dried sewage sludge to investigate the effect of their physical properties on their mercury adsorption efficiency. Using two simulated flue gas conditions, we conducted mercury speciation for the outlet gas. We found that the sewage sludge activated carbon had comparable mercury adsorption efficiency to pinewood and coal activated carbons, and the presence of HCl minimized the effect of physical property of the activated carbon on its mercury adsorption efficiency.

  17. Experience with a pilot plant for sewage sludge: Experiments on the inactivation of viruses in sewage sludge after a radiation treatment

    International Nuclear Information System (INIS)

    Epp, C.

    1975-01-01

    Investigations examining the virus inactivating effect of a Cobalt-60-plant were, till now, limited to the attempts to isolate virus from the sludge samples taken from sewage sludge before and after irradiation with 300 krad. As in those sludge samples virus presence could be proven only on a rather irregular basis, an experiment was devised in which defined virus quantities were packed into capsules and mixed with the digested sludge. At the end of the hygienization process these capsules were removed from the sludge and examined for virus content. Furthermore one radiation volume (5.6 m 3 ) was infected with attenuated polio virus type I and the virus content was determined before and after the radiation treatment. In 33 sludge samples examined before hygienization, presence of one or several viruses occurred in 8 samples. With the 33 capsules examined after hygienization with 300 krad, only 2 showed presence of virus. Suspensions of attenuated polio virus type I packed into synthetic capsules with a medium virus dosis of 10sup(6.92) JD 50/0.1 were immersed into sludge. In 6 experiments it was found that after hygienization, virus dosis was reduced to an average value of 10sup(5.4) JD 50/0.1 ml. Accordingly, the experimental results showed that after the radiation treatment the reduction of the exposed virus was more than 90%. Under natural conditions the investigation of the sewage sludge samples showed presence of virus 4 times less after hygienization than in the samples examined before hygienization. (orig./AK) [de

  18. Regulatory impact analysis of the part 503 sewage sludge regulation. Final report

    International Nuclear Information System (INIS)

    Burris, S.

    1992-01-01

    The report evaluates the costs, benefits, and economic impacts of the final 40 CFR Part 503 regulation governing the use of disposal of sewage sludge generated during the treatment of domestic sewage in a treatment works and domestic septage. The report begins by describing some relevant characteristics of treatment works and domestic septage haulers. The report focuses on the costs, risks, and benefits of the Part 503 regulation

  19. 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...

  20. Guidance for writing permits for the use or disposal of sewage sludge. Draft report

    Energy Technology Data Exchange (ETDEWEB)

    1993-03-01

    Section 405(d) of the Clean Water Act (CWA) directs the U.S. Environmental Protection Agency (EPA) to develop regulations containing guidelines for the use and disposal of sewage sludge. On February 19th, 1993, EPA published final regulations at 40 Code of Federal Regulations (CFR) Part 503 as the culmination of a major effort to develop technical standards in response to Section 405(d). These regulations govern three sewage sludge use and disposal practices: land application, surface disposal, and incineration. A key element in EPA's implementation of the Part 503 regulations is educating Agency and State personnel about these new requirements. Although the regulations are generally directly enforceable against all persons involved in the use and disposal of sewage sludge, they will also be implemented through permits issued to treatment works treating domestic sewage as defined in 40 CFR 122.22. Thus, the primary focus of the manual is to assist permit writers in incorporating the Part 503 requirements into permits; it serves as an update to the Guidance for Writing Case-by-Case Permit Conditions for Municipal Sewage Sludge (PB91-145508/HDM).

  1. Effect of hydrothermal carbonization on migration and environmental risk of heavy metals in sewage sludge during pyrolysis.

    Science.gov (United States)

    Liu, Tingting; Liu, Zhengang; Zheng, Qingfu; Lang, Qianqian; Xia, Yu; Peng, Nana; Gai, Chao

    2018-01-01

    The heavy metals distribution during hydrothermal carbonization (HTC) of sewage sludge, and pyrolysis of the resultant hydrochar was investigated and compared with raw sludge pyrolysis. The results showed that HTC reduced exchangeable/acid-soluble and reducible fraction of heavy metals and lowered the potential risk of heavy metals in sewage sludge. The pyrolysis favored the transformation of extracted/mobile fraction of heavy metals to residual form especially at high temperature, immobilizing heavy metals in the chars. Compared to the chars from raw sludge pyrolysis, the chars derived from hydrochar pyrolysis was more alkaline and had lower risk and less leachable heavy metals, indicating that pyrolysis imposed more positive effect on immobilization of heavy metals for the hydrochar than for sewage sludge. The present study demonstrated that HTC is a promising pretreatment prior to pyrolysis from the perspective of immobilization of heavy metals in sewage sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Phosphorus bioavailability in straw and sewage sludge ashes from low-temperature biomass gasification

    DEFF Research Database (Denmark)

    Müller-Stöver, Dorette Sophie; Jakobsen, Iver; Grønlund, Mette

    2017-01-01

    to their P bioavailability. A set of pot experiments with spring barley was carried out to compare the ash P fertiliser value with mineral P fertiliser and the sewage sludge feedstock. An indirect radioactive labelling approach with 33P was used to determine the amount of P taken up from the fertiliser....... In contrast, low- temperature gasification of Fe-rich sewage sludge reduced its P fertiliser value to practically zero. The results suggest that ashes from low-temperature gasification could be developed into alternative P fertilisers, however since their P bioavailability varies strongly depending...

  3. Technical support document for the surface disposal of sewage sludge. Final report

    International Nuclear Information System (INIS)

    1992-11-01

    The document provides the technical background and justification for the U.S. Environmental Protection Agency's (EPA) final regulation (40 CFR Part 503) covering the surface disposal of sewage sludge. The document summarizes current practices in land application and presents data supporting the risk assessment methodology used to derive human health and environmental risk-based limits for contaminants in sewage sludge placed on surface disposal sites. The management practices associated with surface disposal are outlined and the different pathways by which contaminants reach highly-exposed individuals (HEIs) through surface disposal are discussed

  4. Technical support document for the surface disposal of sewage sludge. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1992-11-01

    The document provides the technical background and justification for the U.S. Environmental Protection Agency's (EPA) final regulation (40 CFR Part 503) covering the surface disposal of sewage sludge. The document summarizes current practices in land application and presents data supporting the risk assessment methodology used to derive human health and environmental risk-based limits for contaminants in sewage sludge placed on surface disposal sites. The management practices associated with surface disposal are outlined and the different pathways by which contaminants reach highly-exposed individuals (HEIs) through surface disposal are discussed.

  5. Modern disposal techniques for sewage sludge and municipal waste; Moderne Entsorgungsverfahren fuer Klaerschlamm und Hausmuell

    Energy Technology Data Exchange (ETDEWEB)

    Garlipp, G. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany); Maczek, K. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany); Steinkamp, H. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany)

    1996-05-01

    Since the passing of the technical code on municipal waste, the issue of the disposal of sewage sludge and municipal waste has become more and more important in Germany. Increasingly, the possibility is made use of to burn industrial and municipal sewage sludge and municipal waste. For such thermal disposal, a great number of techniques are nowadays available. (orig.) [Deutsch] Seit der Verabschiedung der TA Siedlungsabfall gewinnt die Problematik der Entsorgung von Klaerschlamm und Hausmuell in Deutschland zunehmend an Bedeutung. Von der Moeglichkeit, industrielle und kommunale Klaerschlaemme und Hausmuell zu verbrennen, wird in zunehmendem Masse Gebrauch gemacht. Zur thermischen Entsorgung von Klaerschlaemmen und Hausmuell stehen heute eine Vielzahl von Verfahren zur Verfuegung. (orig.)

  6. Disposal of sewage sludge - problems and options; Klaerschlammentsorgung - Probleme und Moeglichkeiten

    Energy Technology Data Exchange (ETDEWEB)

    Kobelt, G.

    2000-06-01

    Sewage sludge production cannot be avoided. In consequence, the sewage sludge produced must either be utilised or combusted for heat and power generation. [German] Da Klaerschlaemme bei der Abwasserreinigung zwangsmaessig anfallen, ist ihre Vermeidung im Sinne des Paragraphen 4 (1), 1 des KrW/AbfG nicht moeglich. Deshalb muss es das Ziel einer vernuenftigen und geordneten Klaerschlammwirtschaft sein, den groesstmoeglichen Anteil des gesamten Schlammaufkommens, wie es das Gesetz ebenfalls vorschreibt, stofflich zu verwerten oder zur Gewinnung von Energie zu nutzen (energetische Verwertung). (orig.)

  7. Technical support document for land application of sewage sludge. Volume 1. Final report

    International Nuclear Information System (INIS)

    Jones, A.; Beyer, L.; Rookwood, M.; Pacenka, J.; Bergin, J.

    1992-11-01

    The document provides the technical background and justification for the U.S. Environmental Protection Agency's (EPA) final regulation (40 CFR Part 503) covering the land application of sewage sludge. The document summarizes current practices in land application and presents data supporting the risk assessment methodology used to derive human health and environmental risk-based limits for contaminants in land applied sewage sludge. The management practices associated with land application are outlined and the different pathways by which contaminants reach highly-exposed individuals (HEIs) through land application are discussed

  8. Mechanical and Physical Properties of Hydrophobized Lightweight Aggregate Concrete with Sewage Sludge.

    Science.gov (United States)

    Suchorab, Zbigniew; Barnat-Hunek, Danuta; Franus, Małgorzata; Łagód, Grzegorz

    2016-04-27

    This article is focused on lightweight aggregate-concrete modified by municipal sewage sludge and lightweight aggregate-concrete obtained from light aggregates. The article presents laboratory examinations of material physical parameters. Water absorptivity of the examined material was decreased by the admixture of water emulsion of reactive polysiloxanes. Water transport properties were determined using Time Domain Reflectometry, an indirect technique for moisture detection in porous media. Together with basic physical parameters, the heat conductivity coefficient λ was determined for both types of lightweight aggregate-concrete. Analysis of moisture and heat properties of the examined materials confirmed the usefulness of light aggregates supplemented with sewage sludge for prospective production.

  9. Yield of castor bean fertilized with sewage sludge and potassium and magnesium sulphate

    OpenAIRE

    Cavalcanti,Thâmara F. M.; Zuba,Geraldo R.; Sampaio,Regynaldo A.; Carneiro,João P.; Oliveira,Ely S. A. de; Rodrigues,Márcio N.

    2015-01-01

    ABSTRACTThe aim of this study was to evaluate the yield and nutrition of castor bean in response to fertilization with sewage sludge and potassium (K) and magnesium (Mg) sulphate. The experiment was carried out from January to July 2011. The treatments, in a randomized block design with three replicates, in a Nitosol, corresponded to a factorial scheme (2 x 4 +1): two doses of K and Mg sulphate combined with four doses of sewage sludge (0, 2.60, 5.20 and 10.40 t ha-1, dry basis), applied base...

  10. Radiation treatment of sewage sludge - experience with an operating pilot plant

    International Nuclear Information System (INIS)

    Suess, A.; Lessel, T.

    1977-01-01

    After an operation time of a pilot plant for the γ-irradiation of sewage sludge after 3 years promising results could be obtained for economic considerations, killing rate of pathogenes and radiation induced changes in sedimentation properties. Irradiated sewage sludge indicated nearly the same effect on soil and plant as untreated. No special trained personnel are necessary for maintenance because of the simple design. Successful experience during 18 months resulted in an increase of the daily capacity up to 120 m 3 from December 1975. (author)

  11. Ten year experience in operation of a sewage sludge treatment plant using gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lessel, T [Abwasserverband Ampergruppe, Eichenau/Muenchen (Germany, F.R.); Suess, A [Bayerische Landesanstalt fuer Bodenkultur und Pflanzenbau, Muenchen (Germany, F.R.)

    1984-01-01

    The first sewage sludge gamma irradiation plant in a technical scale, using Co-60 has been successfully working in Geiselbullach near Munich, FRG, since July 1973. More than 250,000 m/sup 3/ of liquid sludge has been disinfected during that time. Very simple plant design, fully automatic operation over 24 hours and high availability proved the practical applicability of such a facility in a sewage water purification plant without any specially skilled personnel. Beside wide investigations for hygienic aspects, changing of the physical sludge characteristics, effect of irradiated sludge on soil and plants the economic considerations were regarded as important. Experiments were undertaken to optimize the flexibility of the plant operation and to reduce the necessary radiation dose for minimizing the operation costs.

  12. Ten year experience in operation of a sewage sludge treatment plant using gamma irradiation

    International Nuclear Information System (INIS)

    Lessel, T.; Suess, A.

    1984-01-01

    The first sewage sludge gamma irradiation plant in a technical scale, using Co-60 has been successfully working in Geiselbullach near Munich, FRG, since July 1973. More than 250,000 m 3 of liquid sludge has been disinfected during that time. Very simple plant design, fully automatic operation over 24 hours and high availability proved the practical applicability of such a facility in a sewage water purification plant without any specially skilled personnel. Beside wide investigations for hygienic aspects, changing of the physical sludge characteristics, effect of irradiated sludge on soil and plants the economic considerations were regarded as important. Experiments were undertaken to optimize the flexibility of the plant operation and to reduce the necessary radiation dose for minimizing the operation costs. (author)

  13. Use of Municipal Sewage Sludge for Improvement of Forest Sites in the Southeast

    Energy Technology Data Exchange (ETDEWEB)

    Charles R. Berry

    1987-09-01

    In eight field experiments dried municipal sewage sludge was applied to forest sites before planting of seedlings. In all cases, tree growth was faster on sludge-amended plots than on plots that received fertilizer and lime or no amendment. In all studies, concentrations of total nitrogen in the soil were higher on sludge plots than on control or fertilizer plots, even on good forest sites. In seven of the eight studies, concentrations of phosphorus also were higher on sludge plots than on control or fertilizer plots. Nitrogen and phosphorus tended to be higher in foliage from trees growing on sludge plots. Deep subsoiling was beneficial regardless of soil amendment. Where weeds were plentiful at the outset, they became serious competitors on plots receiving sludge.

  14. Restoration of pyritic colliery waste with sewage sludge in the Midlands coalfield, England, United Kingdom

    International Nuclear Information System (INIS)

    Humphries, R.N.; McQuire, G.E.; Sly, M.

    1994-01-01

    A trial was set up in 1990 in the Midlands coalfield in the United Kingdom (UK) to evaluate the use of sewage sludge to revegetate colliery waste tips containing 1--2% sulfur as iron pyrites. The rate of sewage sludge application is currently restricted by legislation and codes of practice to maximum concentrations of potentially toxic elements (copper, nickel, zinc, etc.) in the soil or waste after application. Following this guidance, an application rate of 250 mt/ha dry solids was applied at the trial site. At this rate, the colliery waste became extremely acidic pH <4.0. From experience elsewhere, much higher levels have been found to be necessary to control acidification in the absence of other measures or treatments. In view of the restriction on the amount of sewage sludge that can be applied, it is recommended that the current practice of covering fresh colliery wastes with soil or low sulfur spoil to a minimum depth of 0.45m is continued in the UK. Where this is not possible, the sludge must always be applied with sufficient neutralizing agent to control the potential acidity. If the acidity cannot be maintained above pH 5.0, the guidelines do not permit the application of sewage sludge

  15. 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.

  16. Assessment of mobility and bioavailability of mercury compounds in sewage sludge and composts.

    Science.gov (United States)

    Janowska, Beata; Szymański, Kazimierz; Sidełko, Robert; Siebielska, Izabela; Walendzik, Bartosz

    2017-07-01

    Content of heavy metals, including mercury, determines the method of management and disposal of sewage sludge. Excessive concentration of mercury in composts used as organic fertilizer may lead to accumulation of this element in soil and plant material. Fractionation of mercury in sewage sludge and composts provides a better understanding of the extent of mobility and bioavailability of the different mercury species and helps in more informed decision making on the application of sludge for agricultural purposes. The experimental setup comprises the composing process of the sewage sludge containing 13.1mgkg -1 of the total mercury, performed in static reactors with forced aeration. In order to evaluate the bioavailability of mercury, its fractionation was performed in sewage sludge and composts during the process. An analytical procedure based on four-stage sequential extraction was applied to determine the mercury content in the ion exchange (water soluble and exchangeable Hg), base soluble (Hg bound to humic and fulvic acid), acid soluble (Hg bound to Fe/Mn oxides and carbonates) and oxidizable (Hg bound to organic matter and sulphide) fractions. The results showed that from 50.09% to 64.55% of the total mercury was strongly bound to organo-sulphur and inorganic sulphide; that during composting, increase of concentrations of mercury compounds strongly bound with organic matter and sulphides; and that mercury content in the base soluble and oxidizable fractions was strongly correlated with concentration of dissolved organic carbon in those fractions. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Evaluation of the energetic potential of sewage sludge by characterization of its organic composition.

    Science.gov (United States)

    Schaum, C; Lensch, D; Cornel, P

    2016-01-01

    The composition of sewage sludge and, thus, its energetic potential is influenced by wastewater and wastewater treatment processes. Higher or lower heating values (HHV or LHV) are decisive factors for the incineration/gasification/pyrolysis of sewage sludge. The HHV is analyzed with a bomb calorimeter and converted to the LHV. It is also possible to calculate the heating value via chemical oxygen demand (COD), total volatile solids (TVS), and elemental composition. Calculating the LHV via the COD provides a suitable method. In contrast, the correlation of the HHV or LHV with the TVS is limited. One prerequisite here is a constant specific energy density; this was given with the types of sewage sludge (primary, surplus/excess, and digested sludge) investigated. If the energy density is not comparable with sewage sludge, for instance with the co-substrate (bio-waste, grease, etc.), the estimation of the heating value using TVS will fail. When calculating the HHV or LHV via the elemental composition, one has to consider the validity of the coefficients of the calculation equation. Depending on the organic composition, it might be necessary to adjust the coefficients, e.g. when adding co-substrates.

  18. Fate of stable strontium in the sewage treatment process as an analog for radiostrontium released by nuclear accidents

    International Nuclear Information System (INIS)

    Kamei-Ishikawa, Nao; Ito, Ayumi; Umita, Teruyuki

    2013-01-01

    Highlights: • 76% of the Sr entering the plant was discharged to receiving water. • 21% of the Sr flowing through the plant was transferred to the sewage sludge. •Almost all of the Sr in the sewage sludge was concentrated in incinerated sewage sludge ash. • Activated sludge had a lower sorption capacity for Sr than metals such as Cd. -- Abstract: Radionuclides were widely released into the environment due to the nuclear accident at the Fukushima Daiichi Nuclear Power Plant. Some of these radionuclides have flowed into municipal sewage treatment plants through sewer systems. We have observed the fate of stable Sr in the sewage treatment process as a means to predict the fate of radiostrontium. Concentrations of stable Sr were determined in sewage influent, effluent, dewatered sludge, and incinerated sewage sludge ash collected from a sewage treatment plant once a month from July to December 2011. In the mass balance of Sr in the sewage treatment plant, 76% of the Sr entering the plant was discharged to the receiving water on average. Additionally, 14% of the Sr flowing through the plant was transferred to the sewage sludge and then concentrated in the sludge ash without being released to the atmosphere. We also investigated Sr sorption by activated sludge in a batch experiment. Measurements at 3 and 6 h after the contact showed Sr was sorbed in the activated sludge; however, the measurements indicated Sr desorption from activated sludge occurred 48 h after the contact

  19. Sewage Sludge Disposal with Energy Recovery by Fluidized Bed Gasification and CHP-Units

    Energy Technology Data Exchange (ETDEWEB)

    Horst, J.; Gross, B.; Kimmerle, K. [Inst. fuer ZukunftsEnergieSysteme, Saarbruecken (Germany); Eder, C. [Christian Eder Technology e.K., Neunkirchen (Germany)

    2006-07-15

    Sewage sludge is a composition of by-products collected during the different stages of the waste water cleaning process of communal and industrial treatment plants. Because of its harmful impacts on environment as well as animals - and mankind - health sewage sludge has become a problem. Therefore disposal of sludge is today on a crossroad depending on the discussion about soil contamination by using the sludge as fertiliser. Some countries are now abandoning disposal to agriculture and are entering into thermal treatment with the argument: 'Harmful substances already separated with high financial effort should definitely be removed from the food cycle and should not return indirectly via the fields to food and water'. The SEDIS project - a project funded by the European Commission under the specific research and technological development programme 'Promotion of innovation and encouragement of SME participation' - is aimed at eliminating the rising disposal problem of sewage sludge by an energy-related use of the raw sludge directly on site of wastewater treatment plants. SEDIS is developing an innovative, self-sustaining system to process liquid and pasty waste such as sewage sludge and solid biomass to utilise product-gas for power-generation direct on site. This process is called ETVS-process and is patented by Christian Eder Technology e.K. Today, where each company has to look for sustainable savings, the SEDIS concept offers a decentralised process, self-sustaining from other energy sources and able to provide the whole treatment plant with energy. Furthermore the treatment plant would be independent of price policy of sludge disposers.

  20. Inactivation of bacteria in sewage sludge by ionizing radiation, heat, and thermoradiation

    International Nuclear Information System (INIS)

    Brandon, J.R.; Langley, S.L.

    1976-01-01

    For purposes of animal feeding or fertilizer usage on edible crops, sewage sludge must be free of pathogenic organisms. Bacterial inactivation by a combination of heat and irradiation is shown to be effective. These results must be viewed in conjunction with those from studies of parasite egg inactivation, virus inactivation, and physical-chemical benefits in order to make a fair assessment of the value of the thermoradiation treatment compared to other possible sludge treatment processes

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

    OpenAIRE

    Stanisław Ledakowicz; Paweł Stolarek; A. Malinowski

    2016-01-01

    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 ...

  2. Sewage sludge pasteurization by gamma radiation: A Canadian demonstration project — 1988-91

    Science.gov (United States)

    Swinwood, Jean F.; Wilson, Bruce K.

    Nordion International Inc. and a Canadian city, in cooperation with the Federal & Provincial Ministries of the Environment, began a project in 1988 to construct and operate a commercial-scale sewage sludge pasteurization facility using gamma radiation technology. The facility is scheduled to begin operations in 1991. This paper discusses the objectives and scope of the project, the design of the irradiation system, and the plans to market the pasteurized sludge as a high-value, organic soil conditioner and fertilizer.

  3. Equilibrium sampling reveals increasing thermodynamic potential of polycyclic aromatic hydrocarbons during sewage sludge digestion

    DEFF Research Database (Denmark)

    Sjøholm, Karina Knudsmark; Nørgaard Schmidt, Stine; Jahnke, Annika

    2018-01-01

    The reuse of digested sludge from wastewater treatment plants (WWTPs) as soil fertilizer poses a risk for contamination of soil and water environments. The present study provides a new approach for investigating the exposure of hydrophobic organic chemicals in sewage sludge. The methodology...... (Cfree). The PAHs with logKow > 6 had ARs close to 1.3, whereas PAHs with logKow sediment....

  4. Sewage sludge disintegration by combined treatment of alkaline+high pressure homogenization.

    Science.gov (United States)

    Zhang, Yuxuan; Zhang, Panyue; Zhang, Guangming; Ma, Weifang; Wu, Hao; Ma, Boqiang

    2012-11-01

    Alkaline pretreatment combined with high pressure homogenization (HPH) was applied to promote sewage sludge disintegration. For sewage sludge with a total solid content of 1.82%, sludge disintegration degree (DD(COD)) with combined treatment was higher than the sum of DD(COD) with single alkaline and single HPH treatment. NaOH dosage ⩽0.04mol/L, homogenization pressure ⩽60MPa and a single homogenization cycle were the suitable conditions for combined sludge treatment. The combined sludge treatment showed a maximum DD(COD) of 59.