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Sample records for anaerobic sewage sludge

  1. 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.

  2. [Distribution and removal of anaerobic antibiotic resistant bacteria during mesophilic anaerobic digestion of sewage sludge].

    Science.gov (United States)

    Tong, Juan; Wang, Yuan-Yue; Wei Yuan, Song

    2014-10-01

    Sewage sludge is one of the major sources that releasing antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARG) into the environment since it contains large amount of ARB, but there is little information about the fate of the anaerobic ARB in the anaerobic digestion of sewage sludge. Therefore, the distribution, removal and seasonal changes of tetracycline and β-lactam antibiotics resistant bacteria in the mesophilic egg-shaped digesters of a municipal wastewater treatment plant were investigated for one year in this study. Results showed that there were higher amounts of ARB and higher resistance rate of β-lactam antibiotics than that of tetracycline antibiotics in the sewage sludge. All ARB could be significantly reduced during the mesophilic anaerobic digestion process by 1.48-1.64 log unit (P anaerobic digestion by 12.0% and 14.3%, respectively (P bacteria, there were more ARB in the sewage sludge in cold season than in warm season (P < 0.05).

  3. 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

  4. 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...

  5. 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.

  6. 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.

  7. 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)

  8. 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.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  11. 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).

  12. Anaerobic co-digestion of swine and poultry manure with municipal sewage sludge.

    Science.gov (United States)

    Borowski, Sebastian; Domański, Jarosław; Weatherley, Laurence

    2014-02-01

    The anaerobic digestion of municipal sewage sludge (SS) with swine manure (SM) and poultry manure (PM) was undertaken. It was found that a mixture of sewage sludge with a 30% addition of swine manure gave around 400 dm(3)/kg VS of biogas, whereas the maximal biogas yield from ternary mixture (SS:SM:PM=70:20:10 by weight) was only 336 dm(3)/kg VS. An inhibition of methanogenesis by free ammonia was observed in poultry manure experiments. The anaerobic digestion was inefficient in pathogen inactivation as the reduction in the number of E. coli an Enterobacteriaceae was only by one logarithmic unit. A substantial portion of pathogens was also released into the supernatant. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Modified anaerobic digestion elutriated phased treatment for the anaerobic co-digestion of sewage sludge and food wastewater.

    Science.gov (United States)

    Mo, Kyung; Lee, Wonbae; Kim, Moonil

    2017-02-01

    A modified anaerobic digestion elutriated phased treatment (MADEPT) process was developed for investigating anaerobic co-digestion of sewage sludge and food wastewater. The anaerobic digestion elutriated phased treatment (ADEPT) process is similar to a two-phase system, however, in which the effluent from a methanogenic reactor recycles into an acidogenic reactor to elutriate mainly dissolved organics. Although ADEPT could reduce reactor volume significantly, the unsolubilized solids should be wasted from the system. The MADEPT process combines thermo-alkali solubilization with ADEPT to improve anaerobic performance and to minimize the sludge disposal. It was determined that the optimal volume mixing ratio of sewage sludge and food wastewater was 4 : 1 for the anaerobic co-digestion. The removal efficiencies of total chemical oxygen demand, volatile solids, and volatile suspended solids in the MADEPT process were 73%, 70%, and 64%, respectively. However, those in the ADEPT process were only 48%, 37%, and 40%, respectively, at the same hydraulic retention time (HRT) of 7 days. The gas production of MADEPT was two times higher than that of ADEPT. The thermo-alkali solubilization increased the concentration of dissolved organics so that they could be effectively degraded in a short HRT, implying that MADEPT could improve the performance of ADEPT in anaerobic co-digestion.

  14. Microalgae Cultivation on Anaerobic Digestate of Municipal Wastewater, Sewage Sludge and Agro-Waste

    Directory of Open Access Journals (Sweden)

    Luca Zuliani

    2016-10-01

    Full Text Available Microalgae are fast-growing photosynthetic organisms which have the potential to be exploited as an alternative source of liquid fuels to meet growing global energy demand. The cultivation of microalgae, however, still needs to be improved in order to reduce the cost of the biomass produced. Among the major costs encountered for algal cultivation are the costs for nutrients such as CO2, nitrogen and phosphorous. In this work, therefore, different microalgal strains were cultivated using as nutrient sources three different anaerobic digestates deriving from municipal wastewater, sewage sludge or agro-waste treatment plants. In particular, anaerobic digestates deriving from agro-waste or sewage sludge treatment induced a more than 300% increase in lipid production per volume in Chlorella vulgaris cultures grown in a closed photobioreactor, and a strong increase in carotenoid accumulation in different microalgae species. Conversely, a digestate originating from a pilot scale anaerobic upflow sludge blanket (UASB was used to increase biomass production when added to an artificial nutrient-supplemented medium. The results herein demonstrate the possibility of improving biomass accumulation or lipid production using different anaerobic digestates.

  15. Diversity Profile of Microbes Associated with Anaerobic Sulfur Oxidation in an Upflow Anaerobic Sludge Blanket Reactor Treating Municipal Sewage

    Science.gov (United States)

    Aida, Azrina A.; Kuroda, Kyohei; Yamamoto, Masamitsu; Nakamura, Akinobu; Hatamoto, Masashi; Yamaguchi, Takashi

    2015-01-01

    We herein analyzed the diversity of microbes involved in anaerobic sulfur oxidation in an upflow anaerobic sludge blanket (UASB) reactor used for treating municipal sewage under low-temperature conditions. Anaerobic sulfur oxidation occurred in the absence of oxygen, with nitrite and nitrate as electron acceptors; however, reactor performance parameters demonstrated that anaerobic conditions were maintained. In order to gain insights into the underlying basis of anaerobic sulfur oxidation, the microbial diversity that exists in the UASB sludge was analyzed comprehensively to determine their identities and contribution to sulfur oxidation. Sludge samples were collected from the UASB reactor over a period of 2 years and used for bacterial 16S rRNA gene-based terminal restriction fragment length polymorphism (T-RFLP) and next-generation sequencing analyses. T-RFLP and sequencing results both showed that microbial community patterns changed markedly from day 537 onwards. Bacteria belonging to the genus Desulforhabdus within the phylum Proteobacteria and uncultured bacteria within the phylum Fusobacteria were the main groups observed during the period of anaerobic sulfur oxidation. Their abundance correlated with temperature, suggesting that these bacterial groups played roles in anaerobic sulfur oxidation in UASB reactors. PMID:25817585

  16. 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

  17. Seeking key microorganisms for enhancing methane production in anaerobic digestion of waste sewage sludge.

    Science.gov (United States)

    Mustapha, Nurul Asyifah; Hu, Anyi; Yu, Chang-Ping; Sharuddin, Siti Suhailah; Ramli, Norhayati; Shirai, Yoshihito; Maeda, Toshinari

    2018-04-25

    Efficient approaches for the utilization of waste sewage sludge have been widely studied. One of them is to use it for the bioenergy production, specifically methane gas which is well-known to be driven by complex bacterial interactions during the anaerobic digestion process. Therefore, it is important to understand not only microorganisms for producing methane but also those for controlling or regulating the process. In this study, azithromycin analogs belonging to macrolide, ketolide, and lincosamide groups were applied to investigate the mechanisms and dynamics of bacterial community in waste sewage sludge for methane production. The stages of anaerobic digestion process were evaluated by measuring the production of intermediate substrates, such as protease activity, organic acids, the quantification of bacteria and archaea, and its community dynamics. All azithromycin analogs used in this study achieved a high methane production compared to the control sample without any antibiotic due to the efficient hydrolysis process and the presence of important fermentative bacteria and archaea responsible in the methanogenesis stage. The key microorganisms contributing to the methane production may be Clostridia, Cladilinea, Planctomycetes, and Alphaproteobacteria as an accelerator whereas Nitrosomonadaceae and Nitrospiraceae may be suppressors for methane production. In conclusion, the utilization of antibiotic analogs of macrolide, ketolide, and lincosamide groups has a promising ability in finding the essential microorganisms and improving the methane production using waste sewage sludge.

  18. Dynamics of brominated flame retardants removal in contaminated wastewater sewage sludge under anaerobic conditions.

    Science.gov (United States)

    Stiborova, Hana; Vrkoslavova, Jana; Pulkrabova, Jana; Poustka, Jan; Hajslova, Jana; Demnerova, Katerina

    2015-11-15

    Disposal of solid waste to landfills from waste water sewage treatment plants (WWTPs) serves as a potential source of contamination by polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). Native microbial communities have been found to degrade a variety of xenobiotics, such as PBDEs and HBCDs. This study investigates the potential of autochthonous microflora to remove 11 PBDE congeners and HBCDs in waste water sludge under anaerobic conditions. Laboratory microcosms were constructed with sewage sludge from the WWTPs of Hradec Kralove and Brno. BDE 209 was detected as the prevailing congener in concentrations 685 and 1403 ng/g dw and the total amounts of 10 lower PBDEs (BDE 28, 47, 49, 66, 85, 99, 100, 153, 154, 183) were 605 and 205 ng/g dw in sludge from Hradec Kralove and Brno, respectively. The levels of HBCD were detected in both sludge lower than 24 ng/g dw. The experiment was carried out for 15 months. After three months of incubation, HBCD was completely degraded to below detection limits. In sewage from both WWTPs, the higher brominated DEs were removed faster than the lower brominated congeners. One exception was tri-BDE, which was degraded completely within 15 months of cultivation. A significant increase in congener tetra-BDE 49 concentrations was observed over the course of the experiment in all tested sewage. The relative distribution of individual congeners among all PBDEs changed after 15 months of the incubation in favour of lower brominated congeners. This indicates that debromination is the major mechanism of anaerobic biodegradation. Despite of the increase of BDE 49, the overall removal of all 11 PBDEs achieved the levels of 47.4 and 68.7% in samples from WWTPs Hradec Kralove and Brno, respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. The Leachate Release and Microstructure of the Sewage Sludge under the Anaerobic Fermentation

    Directory of Open Access Journals (Sweden)

    Yiqie Dong

    2015-01-01

    Full Text Available Pollutant release, pore structure, and thermal effect of sewage sludge during anaerobic fermentation were investigated. Results showed that the pH value firstly declined and then increased during anaerobic fermentation. The BOD5 and organics of sewage sludge declined, and the BOD5 of samples which was originally neutral declined as much as 53.6%. The micropore of samples was relatively developed. The biggest adsorption amount was 69.2 cm3/g. The average pore size was enlarged about 16.0–19.8% under anaerobic fermentation. There existed endothermic valley during heating procedure of 0–200∘C because of the dehydration, and the mass loss was 60.9–72.5%. The endothermic valley of the sample fluctuated at the 14th day in the anaerobic fermentation. During the heating procedure of 200–600∘C, there existed exothermal peaks because of the oxidation and burning of the organics. The curve of sample which was originally neutral had comparatively large endothermic valley and exothermal peak.

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

    Science.gov (United States)

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

    2013-01-01

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

  1. Anaerobic co-digestion of sewage sludge with shredded grass from public green spaces.

    Science.gov (United States)

    Hidaka, Taira; Arai, Sayuri; Okamoto, Seiichiro; Uchida, Tsutomu

    2013-02-01

    Adding greenery from public spaces to the co-digestion process with sewage sludge was evaluated by shredding experiments and laboratory-scale batch and continuous mesophilic anaerobic fermentation experiments. The ratio of the shredded grass with 20mm or less in length by a commercially available shredder was 93%. The methane production was around 0.2NL/gVS-grass in the batch experiment. The continuous experiment fed with sewage sludge and shredded grass was stably operated for 81days. The average methane production was 0.09NL/gVS-grass when the TS ratio of the sewage sludge and the grass was 10:1. This value was smaller than those of other reports using grass silage, but the grass species in this study were not managed, and the collected grass was just shredded and not ensiled before feeding to the reactor for simple operation. The addition of grass to a digester can improve the carbon/nitrogen ratio, methane production and dewaterability. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Inactivation of Clostridium difficile in sewage sludge by anaerobic thermophilic digestion.

    Science.gov (United States)

    Xu, Changyun; Salsali, Hamidreza; Weese, Scott; Warriner, Keith

    2016-01-01

    There has been an increase in community-associated Clostridium difficile infections with biosolids derived from wastewater treatment being identified as one potential source. The current study evaluated the efficacy of thermophilic digestion in decreasing levels of C. difficile ribotype 078 associated with sewage sludge. Five isolates of C. difficile 078 were introduced (final density of 5 log CFU/g) into digested sludge and subjected to anaerobic digestion at mesophilic (36 or 42 °C) or thermophilic (55 °C) temperatures for up to 60 days. It was found that mesophilic digestion at 36 °C did not result in a significant reduction in C. difficile spore levels. In contrast, thermophilic sludge digestion reduced endospore levels at a rate of 0.19-2.68 log CFU/day, depending on the strain tested. The mechanism of lethality was indirect - by stimulating germination then inactivating the resultant vegetative cells. Acidification of sludge by adding acetic acid (6 g/L) inhibited the germination of spores regardless of the sludge digestion temperature. In conclusion, thermophilic digestion can be applied to reduce C. difficile in biosolids, thereby reducing the environmental burden of the enteric pathogen.

  3. Rapid startup of thermophilic anaerobic digester to remove tetracycline and sulfonamides resistance genes from sewage sludge.

    Science.gov (United States)

    Xu, Rui; Yang, Zhao-Hui; Wang, Qing-Peng; Bai, Yang; Liu, Jian-Bo; Zheng, Yue; Zhang, Yan-Ru; Xiong, Wei-Ping; Ahmad, Kito; Fan, Chang-Zheng

    2018-01-15

    Spread of antibiotic resistance genes (ARGs) originating from sewage sludge is highlighted as an eminent health threat. This study established a thermophilic anaerobic digester using one-step startup strategy to quickly remove tetracycline and sulfonamides resistance genes from sewage sludge. At least 20days were saved in the startup period from mesophilic to thermophilic condition. Based on the results of 16S rDNA amplicons sequencing and predicted metagenomic method, the successful startup largely relied on the fast colonization of core thermophilic microbial population (e.g. Firmicutes, Proteobacteria, Actinobacteria). Microbial metabolic gene pathways for substrate degradation and methane production was also increased by one-step mode. In addition, real-time quantitative PCR approach revealed that most targeted tetracycline and sulfonamides resistance genes ARGs (sulI, tetA, tetO, tetX) were substantially removed during thermophilic digestion (removal efficiency>80%). Network analysis showed that the elimination of ARGs was attributed to the decline of their horizontal (intI1 item) and vertical (potential hosts) transfer-related elements under high-temperature. This research demonstrated that rapid startup thermophilic anaerobic digestion of wastewater solids would be a suitable technology for reducing quantities of various ARGs. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Pilot plant experience on anaerobic codigestion of source selected OFMSW and sewage sludge.

    Science.gov (United States)

    Cabbai, Valentina; De Bortoli, Nicola; Goi, Daniele

    2016-03-01

    Anaerobic codigestion of source selected organic fraction of municipal solid waste (SS-OFMSW) and sewage sludge may be one of the most viable solutions to optimize oversized digesters efficiency in wastewater treatment plants. Based on results of BMP tests obtained for sewage sludge and SS-OFMSW, pilot plant tests were carried out by 3.4 m(3) CSTR reactor at mesophilic temperature. A mix of fruit and vegetable waste from wholesale market and canteen waste was used as SS-OFMSW substrate. Tests were conducted applying an OLR (organic loading rate) ramp with 6 different phases until a value of 3.2 kgVS/m(3) d. Feedstock and digestate characteristics, efficiency and process parameters were monitored. The anaerobic codigestion development was stable in each phase: early indicators like VFA (volatile fatty acids) and FOS/TAC ratio were always below instability threshold values. The maximum OLR tested determined a GPR (gas production rate) of 0.95 N m(3)/m(3) d and SGP (specific gas production) of 0.49 N m(3)/kgVS with a VS abatement of 67.3%. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. 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

  6. 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.

  7. Molecular characterization of anaerobic sulfur-oxidizing microbial communities in up-flow anaerobic sludge blanket reactor treating municipal sewage.

    Science.gov (United States)

    Aida, Azrina A; Hatamoto, Masashi; Yamamoto, Masamitsu; Ono, Shinya; Nakamura, Akinobu; Takahashi, Masanobu; Yamaguchi, Takashi

    2014-11-01

    A novel wastewater treatment system consisting of an up-flow anaerobic sludge blanket (UASB) reactor and a down-flow hanging sponge (DHS) reactor with sulfur-redox reaction was developed for treatment of municipal sewage under low-temperature conditions. In the UASB reactor, a novel phenomenon of anaerobic sulfur oxidation occurred in the absence of oxygen, nitrite and nitrate as electron acceptors. The microorganisms involved in anaerobic sulfur oxidation have not been elucidated. Therefore, in this study, we studied the microbial communities existing in the UASB reactor that probably enhanced anaerobic sulfur oxidation. Sludge samples collected from the UASB reactor before and after sulfur oxidation were used for cloning and terminal restriction fragment length polymorphism (T-RFLP) analysis of the 16S rRNA genes of the bacterial and archaeal domains. The microbial community structures of bacteria and archaea indicated that the genus Smithella and uncultured bacteria within the phylum Caldiserica were the dominant bacteria groups. Methanosaeta spp. was the dominant group of the domain archaea. The T-RFLP analysis, which was consistent with the cloning results, also yielded characteristic fingerprints for bacterial communities, whereas the archaeal community structure yielded stable microbial community. From these results, it can be presumed that these major bacteria groups, genus Smithella and uncultured bacteria within the phylum Caldiserica, probably play an important role in sulfur oxidation in UASB reactors. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

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

    NARCIS (Netherlands)

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

    2003-01-01

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

  9. Transferring of components and energy output in industrial sewage sludge disposal by thermal pretreatment and two-phase anaerobic process.

    Science.gov (United States)

    Yang, Xiaoyi; Wang, Xin; Wang, Lei

    2010-04-01

    For a better sewage sludge disposal and more efficient energy reclamation, transforming of components and energy in sludge by thermal and WAO pretreatment followed by two-phase anaerobic UASB process were studied in the pilot scale. Biogas outputs and the qualities and quantities of the effluent and solid residue were compared with a traditional anaerobic sludge digestion. Sludge components, including carbon, nitrogen, phosphorus, sulphur, were observed and mass balances were discussed throughout the process. The input and output energy balance was also studied. Results showed different trait to compare with biogas outputs in terms of COD added and raw sludge added. Pretreatment improved the transformation of carbon substances into biogas production with higher carbon removal and higher VSS removal. Comparing the energy obtained from biogas production with energy inputs required for pretreatment, energy output in the whole process decreased with higher pretreatment temperature. Copyright 2009 Elsevier Ltd. All rights reserved.

  10. Comparative Analysis of Performance and Microbial Characteristics Between High-Solid and Low-Solid Anaerobic Digestion of Sewage Sludge Under Mesophilic Conditions.

    Science.gov (United States)

    Lu, Qin; Yi, Jing; Yang, Dianhai

    2016-01-01

    High-solid anaerobic digestion of sewage sludge achieves highly efficient volatile solid reduction, and production of volatile fatty acid (VFA) and methane compared with conventional low-solid anaerobic digestion. In this study, the potential mechanisms of the better performance in high-solid anaerobic digestion of sewage sludge were investigated by using 454 high-throughput pyrosequencing and real-time PCR to analyze the microbial characteristics in sewage sludge fermentation reactors. The results obtained by 454 high-throughput pyrosequencing revealed that the phyla Chloroflexi, Bacteroidetes, and Firmicutes were the dominant functional microorganisms in high-solid and low-solid anaerobic systems. Meanwhile, the real-time PCR assays showed that high-solid anaerobic digestion significantly increased the number of total bacteria, which enhanced the hydrolysis and acidification of sewage sludge. Further study indicated that the number of total archaea (dominated by Methanosarcina) in a high-solid anaerobic fermentation reactor was also higher than that in a low-solid reactor, resulting in higher VFA consumption and methane production. Hence, the increased key bacteria and methanogenic archaea involved in sewage sludge hydrolysis, acidification, and methanogenesis resulted in the better performance of high-solid anaerobic sewage sludge fermentation.

  11. Mesophilic anaerobic stabilization of sewage sludge. Mesophile anaerobe Klaerschlammstabilisierung mit aerober Folgebehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Stoll, U.

    1988-01-01

    Sludges treated in two stages in experiments - 7 days of anaerobic treatment and 2 days of aerobic-thermophilic treatment - can be judged to be completely stabilized because of the stabilization parameters BOD/sub 5//COD ratio and respiratory activity. The degradation results obtained are comparable to or better than those of the 20-day digestion (reference process). For all aerobic processes under investigation a clear temperature increase in the aerobic reactor was measured because of the exothermal metabolic processes of the aerobic biocenosis. There was a temperature rise of 15/sup 0/C in the tests in the aerobic reactor even after longer digestion times of 15 and 20 days. The results of the epidemics and hygiene investigations show that a secondary aerobic-thermophilic stage after the mesophilic digestion with adequate marginal conditions - germ retention time of 23 hours in the aerobic reactor at process temperatures higher than 50/sup 0/C as well as charging in batch quantities - leads to a safe and complete decontamination. Under these process and operation conditions all salmonellae were killed and the number of the enterobacteriaceae in 1 g of sludge was always less than 1.000. (orig./EF).

  12. Digestion of thermally hydrolyzed sewage sludge by anaerobic sequencing batch reactor

    International Nuclear Information System (INIS)

    Wang Zhijun; Wang Wei; Zhang Xihui; Zhang Guangming

    2009-01-01

    Laboratory experiments were conducted to investigate the performance of an anaerobic sequencing batch reactor (ASBR) for the digestion of thermally hydrolyzed sewage sludge. Both mesophilic ASBR and continuous-flow stirred tank reactors (CSTR) were evaluated with an equivalent loading rate of 2.71 kg COD/m 3 day at 20-day hydraulic retention time (HRT) and 5.42 kg COD/m 3 day at 10-day HRT. The average total chemical oxygen demand (TCOD) removals of the ASBR at the 20-day and 10-day HRT were 67.71% and 61.66%, respectively. These were 12.38% and 27.92% higher than those obtained by CSTR. As a result, the average daily gas production of ASBR was 15% higher than that of the CSTR at 20-day HRT, and 31% higher than that of the CSTR at 10-day HRT. Solids in thermally hydrolyzed sludge accumulated within ASBR were able to reach a high steady state with solid content of 65-80 g/L. This resulted in a relatively high solid retention time (SRT) of 34-40 days in the ASBR at 10-day HRT. However, too much solid accumulation resulted in the unsteadiness of the ASBR, making regular discharge of digested sludge from the bottom of the ASBR necessary to keep the reactor stable. The evolution of the gas production, soluble chemical oxygen demand (SCOD) and volatile fatty acids (VFAs) in an operation cycle of ASBR also showed that the ASBR was steady and feasible for the treatment of thermally hydrolyzed sludge

  13. Fate of Zinc Oxide Nanoparticles during Anaerobic Digestion of Wastewater and Post-Treatment Processing of Sewage Sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lombi, Enzo; Donner, Erica; Tavakkoli, Ehsan; Turney, Terence W.; Naidu, Ravi; Miller, Bradley W.; Scheckel, Kirk G. (U. South Australia); (EPA); (Monash)

    2013-01-14

    The rapid development and commercialization of nanomaterials will inevitably result in the release of nanoparticles (NPs) to the environment. As NPs often exhibit physical and chemical properties significantly different from those of their molecular or macrosize analogs, concern has been growing regarding their fate and toxicity in environmental compartments. The wastewater-sewage sludge pathway has been identified as a key release pathway leading to environmental exposure to NPs. In this study, we investigated the chemical transformation of two ZnO-NPs and one hydrophobic ZnO-NP commercial formulation (used in personal care products), during anaerobic digestion of wastewater. Changes in Zn speciation as a result of postprocessing of the sewage sludge, mimicking composting/stockpiling, were also assessed. The results indicated that 'native' Zn and Zn added either as a soluble salt or as NPs was rapidly converted to sulfides in all treatments. The hydrophobicity of the commercial formulation retarded the conversion of ZnO-NP. However, at the end of the anaerobic digestion process and after postprocessing of the sewage sludge (which caused a significant change in Zn speciation), the speciation of Zn was similar across all treatments. This indicates that, at least for the material tested, the risk assessment of ZnO-NP through this exposure pathway can rely on the significant knowledge already available in regard to other 'conventional' forms of Zn present in sewage sludge.

  14. Effects of disintegration on anaerobic degradation of sewage excess sludge in downflow stationary fixed film digesters.

    Science.gov (United States)

    Engelhart, M; Krüger, M; Kopp, J; Dichtl, N

    2000-01-01

    The effects of mechanical disintegration on anaerobic digestibility of sewage excess sludge in downflow stationary fixed film (DSFF) digesters were investigated on laboratory scale. Mechanical pretreatment using a high pressure homogenizer led to significantly enhanced concentrations of soluble proteins and carbohydrates in the feed sludge. Using DSFF digesters with two different tubular plastic media as support material it was shown that a stable digestion process could be achieved at hydraulic retention times (HRT) down to 5 days. Compared to conventional digesters at 10 d and 15 d HRT respectively, the degradation of volatile solids was enhanced up to 25%, also resulting in a higher specific biogas production. Further investigations on degradation of soluble proteins and carbohydrates showed that a slowly degradable fraction of carbohydrates was released via disintegration. Using the distribution of chain length and the concentrations of volatile fatty acids as process parameters, the dependability on the HRT and the degree of disintegration (the release of soluble COD) predominated the effects of specific surface area of the support media.

  15. Comparative analyses of microbial structures and gene copy numbers in the anaerobic digestion of various types of sewage sludge.

    Science.gov (United States)

    Hidaka, Taira; Tsushima, Ikuo; Tsumori, Jun

    2018-04-01

    Anaerobic co-digestion of various sewage sludges is a promising approach for greater recovery of energy, but the process is more complicated than mono-digestion of sewage sludge. The applicability of microbial structure analyses and gene quantification to understand microbial conditions was evaluated. The results show that information from gene analyses is useful in managing anaerobic co-digestion and damaged microbes in addition to conventional parameters like total solids, pH and biogas production. Total bacterial 16S rRNA gene copy numbers are the most useful tools for evaluating unstable anaerobic digestion of sewage sludge, rather than mcrA and total archaeal 16S rRNA gene copy numbers, and high-throughput sequencing. First order decay rates of gene copy numbers during pH failure were higher than typical decay rates of microbes in stable operation. The sequencing analyses, including multidimensional scaling, showed very different microbial structure shifts, but the results were not consistent. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Impact of food industrial waste on anaerobic co-digestion of sewage sludge and pig manure.

    Science.gov (United States)

    Murto, M; Björnsson, L; Mattiasson, B

    2004-02-01

    The performance of an anaerobic digestion process is much dependent on the type and the composition of the material to be digested. The effects on the degradation process of co-digesting different types of waste were examined in two laboratory-scale studies. In the first investigation, sewage sludge was co-digested with industrial waste from potato processing. The co-digestion resulted in a low buffered system and when the fraction of starch-rich waste was increased, the result was a more sensitive process, with process overload occurring at a lower organic loading rate (OLR). In the second investigation, pig manure, slaughterhouse waste, vegetable waste and various kinds of industrial waste were digested. This resulted in a highly buffered system as the manure contributed to high amounts of ammonia. However, it is important to note that ammonia might be toxic to the micro-organisms. Although the conversion of volatile fatty acids was incomplete the processes worked well with high gas yields, 0.8-1.0 m3 kg(-1) VS.

  17. Effect of the two-stage thermal disintegration and anaerobic digestion of sewage sludge on the COD fractions

    Directory of Open Access Journals (Sweden)

    Ciaciuch Anna

    2017-09-01

    Full Text Available The research presents the changes in chemical oxygen demand (COD fractions during the two-stage thermal disintegration and anaerobic digestion (AD of sewage sludge in municipal wastewater treatment plant (WWTP. Four COD fractions have been separated taking into account the solubility of substrates and their susceptibility to biodegradation: inert soluble organic matter SI, readily biodegradable substrate SS, slowly biodegradable substrates XS and inert particulate organic material XI. The results showed that readily biodegradable substrates SS (46.8% of total COD and slowly biodegradable substrates XS (36.1% of total COD were dominant in the raw sludge effluents. In sewage effluents after two-stage thermal disintegration, the percentage of SS fraction increased to 90% of total COD and percentage of XS fraction decreased to 8% of total COD. After AD, percentage of SS fraction in total COD decreased to 64%, whereas the percentage of other fractions in effluents increased.

  18. Effect of Addition of High Strength Food Wastes on Anaerobic Digestion of Sewage Sludge

    OpenAIRE

    Vaidya, Ramola Vinay

    2015-01-01

    Anaerobic co-digestion of municipal sludge and food wastes high in chemical oxygen demand (COD) has been an area of interest for waste water treatment facilities looking to increase methane production, and at the same time, dispose of the wastes and increase the revenue. However, addition of food wastes containing fats, oils and grease (FOG) to the conventional anaerobic digestion process can be difficult and pose challenges to utilities. Incorporating these wastes into the treatment plants c...

  19. Effects of Physico-Chemical Post-Treatments on the Semi-Continuous Anaerobic Digestion of Sewage Sludge

    Directory of Open Access Journals (Sweden)

    Xinbo Tian

    2017-07-01

    Full Text Available Sludge production in wastewater treatment plants is increasing worldwide due to the increasing population. This work investigated the effects of ultrasonic (ULS, ultrasonic-ozone (ULS-Ozone and ultrasonic + alkaline (ULS+ALK post-treatments on the anaerobic digestion of sewage sludge in semi-continuous anaerobic reactors. Three conditions were tested with different hydraulic retention times (HRT, 10 or 20 days and sludge recycle ratios (R = QR/Qin (%: 50 or 100%. Biogas yield increased by 17.8% when ULS+ALK post-treatment was applied to the effluent of a reactor operating at 20 days HRT and at a 100% recycle ratio. Operation at 10 days HRT also improved the biogas yield (277 mL CH4/g VSadded (VS: volatile solids versus 249 mL CH4/g VSadded in the control. The tested post-treatment methods showed 4–7% decrease in effluent VS. The post-treatment resulted in a decrease in the cellular ATP (Adenosine tri-phosphate concentration indicating stress imposed on microorganisms in the reactor. Nevertheless, this did not prevent higher biogas production. Based on the results, the post-treatment of digested sludge or treating the sludge between two digesters is an interesting alternative to pre-treatments.

  20. Research Regarding the Accumulation in Soybeans of Heavy Metals from Anaerobic Composted Sewage Sludge Used as Organic Fertilizer

    Directory of Open Access Journals (Sweden)

    Benoni Lixandru

    2010-10-01

    Full Text Available In sewage sludge from urban wastewater treatment stations can often be find high levels of Ni, Pb, Cu, Zn, Mn andCd. Aerobic or anaerobic composting of this sewage sludge does not eliminate the possibility of bioaccumulation ofthese metals in plants through metabolic processes of phytoextraction type. Researches regarding the accumulationdegree of heavy metals through phytoextraction processes were performed on soybean plants (Glycine max, Condorvariety. Plants were fertilized with anaerobic composted sludge in amounts of 25 t of / ha, 50 t / ha and 100 t / ha.The chemical analysis was done on an average sample of three repetitions. Metal concentration in soybeans wasanalyzed by reporting to the maximum allowance level for sheep, considered one of the most sensitive farm speciesto heavy metal toxicity. Our results showed a higher level than normal with 5.8 mg / kg only in the case of copperions. Zn, Pb, Mn and Cd concentration in soybeans was below the maximum allowance limits set by the rules offeeding farm animals. Also, heavy metal content of soybeans was not affected by the amount of composted sludgeused as fertilizer.

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

    Science.gov (United States)

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

    2014-05-01

    The increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9 M fractions into batch ADs treating food waste or sewage sludge. Daily specific methane (CH4) production increased 11-16% for food waste and 96-138% for sewage sludge over the first 24h. Potential CO2 reductions of 8-34% for sewage sludge and 3-11% for food waste were estimated. The capacity of ADs to utilise additional CO2 was demonstrated, which could provide a potential solution for onsite sequestration of CO2 streams while enhancing renewable energy production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Anaerobic bioprocessing of sewage sludge, focusing on degradation of linear alkylbenzene sulfonates (LAS)

    Energy Technology Data Exchange (ETDEWEB)

    Angelidaki, I.; Toraeng, L.; Waul, C.M.; Schmidt, J.E.

    2003-07-01

    Anaerobic degradation of sludge amended with linear alkylbenzene sulfonates (LAS) was tested in one stage continuous stirred tank reactor (CSTR) and a two stages reactor system consisting by a CSTR as first step and upflow anaerobic sludge bed (UASB) reactor in the second step. Anaerobic removal of LAS was only observed at the second step but not at the first step. Removal of LAS in the UASB reactors was approx. 80% where half was due to absorption and the other half was apparently due to biological removal as shown from the LAS mass balance. At the end of the experiment the reactors were spiked with {sup 14}C-LAS which resulted in 5.6% {sup 14}CO{sub 2} in the produced gas. Total mass balance of the radioactivity was however not achieved. In batch experiments it was found that LAS at concentrations higher than 50 mg/l is inhibitory for the most microbial groups of the anaerobic process. Therefore, low initial LAS concentration is a prerequisite for successful LAS degradation. The results from the present study suggest that anaerobic degradation of LAS is possible in UASB reactors when the concentration of LAS is low enough to avoid inhibition of microorganisms active in the anaerobic process. (author)

  3. Anaerobic digestion for simultaneous sewage sludge treatment and CO biomethanation: process performance and microbial ecology

    DEFF Research Database (Denmark)

    Luo, Gang; Wang, Wen; Angelidaki, Irini

    2013-01-01

    Syngas is produced by thermal gasification of both non-renewable and renewable sources including biomass and coal, and it consists mainly of CO, CO2 and H2. In this paper we aim to bio-convert CO in the syngas to CH4. A novel technology for simultaneous sewage sludge treatment and CO biomethanation....... However, the two species were distributed differently in the liquid phase and in the biofilm. Although carboxidotrophic activities test showed that CO was converted by both archaea and bacteria, the bacterial species responsible for CO conversion are unknown....

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

    Science.gov (United States)

    Passio, Luca; Rizzoa, Luigi; Fuchs, Stephan

    2012-09-01

    The unsafe disposal of wastewater and sludge in different areas of developing countries results in significant environmental pollution, particularly for groundwater, thus increasing the risk of waterborne diseases spreading. In this work, a two-phase anaerobic digestion process for post-treatment of partially acidified sewage sludge was investigated to evaluate its feasibility as a safe sludge disposal system. Pilot tests showed that an effective sludge stabilization can be achieved (total volatile solids content <65%, organic acid concentration <200 mg/L at flow rate = 50 L/d and hydraulic residence time = 18 d) as well as a relative low faecal coliform density (<1000 most probable number per g total solids), showing that land application of the sludge without restrictions is possible according to US Environmental Protection Agency criteria for safe sludge disposal. A biogas production as high as 390 L/d with a 60% methane content by volume was achieved, showing that energy production from biogas may be achieved as well.

  5. Study of two-phase sewage sludge anaerobic digestion process. 2

    Energy Technology Data Exchange (ETDEWEB)

    Kon, M; Onuma, T; Mori, N; Kakajima, I

    1981-01-01

    Studies have been made on the two-phase moderate temperature digestion process of mixed sludges sampled from various cities. With some mixed sludge, simultaneous acid fermentatin process and methane fermentation process were observed. This simultaneous fermentation processes unfavorably affected the gas generation rate. This advantage was eliminated by preheating the sludge (61 degrees C, 12hr), however, the heat balance was not satisfactory. This study was planned to improve the two-phase digestion process. The improved two-phase digestion process provides an increased methane gas generating rate exceeding that of the conventional method by 20%. The economic effect and the heat balance of the improved two-phase digestion process have been studied by the use of a simulated model of a facility for the sewage sludge treatment plant for 100,000 population city. The results of the simulation provided the possibility of lowering the volume of the digestion tank to 1/3, reducing the necessary site area by 20% and the initial cost by 20% as compared with the conventional process. 1 reference.

  6. 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.

  7. Improving anaerobic sewage sludge digestion by implementation of a hyper-thermophilic prehydrolysis step

    DEFF Research Database (Denmark)

    Lu, Jingquan; Gavala, Hariklia N.; Skiadas, Ioannis V.

    2008-01-01

    The present study focuses on a two-step process for treatment and stabilisation of primary sludge. The process consists of a hyperthermophilic hydrolysis step operated at 70 degrees C and a hydraulic retention time (HRT) of 2 clays followed by a thermophilic (55 degrees C) anaerobic digestion step......) with and Without pre-treatment respectively) and up to 115% increase of the methane production rate. Finally it was shown that the extra energy requirements for the operation of a pre-treatment step would be covered by the energy Produced from the extra methane production and in addition there would...

  8. Co-existence of Anaerobic Ammonium Oxidation Bacteria and Denitrifying Anaerobic Methane Oxidation Bacteria in Sewage Sludge: Community Diversity and Seasonal Dynamics.

    Science.gov (United States)

    Xu, Sai; Lu, Wenjing; Mustafa, Muhammad Farooq; Caicedo, Luis Miguel; Guo, Hanwen; Fu, Xindi; Wang, Hongtao

    2017-11-01

    Anaerobic ammonium oxidation (ANAMMOX) and denitrifying anaerobic methane oxidation (DAMO) have been recently discovered as relevant processes in the carbon and nitrogen cycles of wastewater treatment plants. In this study, the seasonal dynamics of ANAMMOX and DAMO bacterial community structures and their abundance in sewage sludge collected from wastewater treatment plants were analysed. Results indicated that ANAMMOX and DAMO bacteria co-existed in sewage sludge in different seasons and their abundance was positively correlated (P bacteria in autumn and winter indicated that these seasons were the preferred time to favour the growth of ANAMMOX and DAMO bacteria. The community structure of ANNAMOX and DAMO bacteria could also shift with seasonal changes. The "Candidatus Brocadia" genus of ANAMMOX bacteria was mainly recovered in spring and summer, and an unknown cluster was primarily detected in autumn and winter. Similar patterns of seasonal variation in the community structure of DAMO bacteria were also observed. Group B was the dominant in spring and summer, whereas in autumn and winter, group A and group B presented almost the same proportion. The redundancy analysis revealed that pH and nitrate were the most significant factors affecting community structures of these two groups (P < 0.01). This study reported the diversity of ANAMMOX and DAMO in wastewater treatment plants that may be the basis for new nitrogen removal technologies.

  9. Effects of aerobic and anaerobic biological processes on leaching of heavy metals from soil amended with sewage sludge compost.

    Science.gov (United States)

    Fang, Wen; Wei, Yonghong; Liu, Jianguo; Kosson, David S; van der Sloot, Hans A; Zhang, Peng

    2016-12-01

    The risk from leaching of heavy metals is a major factor hindering land application of sewage sludge compost (SSC). Understanding the change in heavy metal leaching resulting from soil biological processes provides important information for assessing long-term behavior of heavy metals in the compost amended soil. In this paper, 180days aerobic incubation and 240days anaerobic incubation were conducted to investigate the effects of the aerobic and anaerobic biological processes on heavy metal leaching from soil amended with SSC, combined with chemical speciation modeling. Results showed that leaching concentrations of heavy metals at natural pH were similar before and after biological process. However, the major processes controlling heavy metals were influenced by the decrease of DOC with organic matter mineralization during biological processes. Mineralization of organic matter lowered the contribution of DOC-complexation to Ni and Zn leaching. Besides, the reducing condition produced by biological processes, particularly by the anaerobic biological process, resulted in the loss of sorption sites for As on Fe hydroxide, which increased the potential risk of As release at alkaline pH. Copyright © 2016 Elsevier Ltd. All rights reserved.

  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. High-solid Anaerobic Co-digestion of Sewage Sludge and Cattle Manure: The Effects of Volatile Solid Ratio and pH

    Science.gov (United States)

    Dai, Xiaohu; Chen, Yang; Zhang, Dong; Yi, Jing

    2016-01-01

    High-solid anaerobic digestion is an attractive solution to the problem of sewage sludge disposal. One method that can be used to enhance the production of volatile fatty acids (VFAs) and the generation of methane from anaerobic digestion involves combining an alkaline pretreatment step with the synergistic effects of sewage sludge and cattle manure co-digestion, which improves the activity of key enzymes and microorganisms in the anaerobic co-digestion system to promote the digestion of organic waste. In this study, we describe an efficient strategy that involves adjusting the volatile solid (VS) ratio (sewage sludge/cattle manure: 3/7) and initial pH (9.0) to improve VFA production and methane generation from the co-digestion of sludge and manure. The experimental results indicate that the maximum VFA production was 98.33 g/kg-TS (total solid) at the optimal conditions. Furthermore, methane generation in a long-term semi-continuously operated reactor (at a VS ratio of 3/7 and pH of 9.0) was greater than 120.0 L/kg-TS. PMID:27725704

  12. 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.

  13. 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

  14. 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)

  15. 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

  16. 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...

  17. Kinetic modelling of methane production during bio-electrolysis from anaerobic co-digestion of sewage sludge and food waste.

    Science.gov (United States)

    Prajapati, Kalp Bhusan; Singh, Rajesh

    2018-05-10

    In present study batch tests were performed to investigate the enhancement in methane production under bio-electrolysis anaerobic co-digestion of sewage sludge and food waste. The bio-electrolysis reactor system (B-EL) yield more methane 148.5 ml/g COD in comparison to reactor system without bio-electrolysis (B-CONT) 125.1 ml/g COD. Whereas bio-electrolysis reactor system (C-EL) Iron Scraps amended yield lesser methane (51.2 ml/g COD) in comparison to control bio-electrolysis reactor system without Iron scraps (C-CONT - 114.4 ml/g COD). Richard and Exponential model were best fitted for cumulative methane production and biogas production rates respectively as revealed modelling study. The best model fit for the different reactors was compared by Akaike's Information Criterion (AIC) and Bayesian Information Criterion (BIC). The bioelectrolysis process seems to be an emerging technology with lesser the loss in cellulase specific activity with increasing temperature from 50 to 80 °C. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. 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.

  19. 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.

  20. 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)

  1. Removal of reactive dye Remazol Brilliant Blue R from aqueous solutions by using anaerobically digested sewage sludge based adsorbents

    Directory of Open Access Journals (Sweden)

    Özçimen Didem

    2016-01-01

    Full Text Available In this study, adsorbents were produced from sewage sludge via chemical and thermal activation processes. Experiments were carried out in a tubular furnace at the heating rate of 20˚C min-1 and temperature of 550 ˚C with a nitrogen flow rate of 400 mL min-1 for 1 h. Dye adsorption experiments were performed with Remazol Brilliant Blue R for its several concentrations under batch equilibrium conditions by comparing sewage sludge based adsorbents with raw material and a commercial activated carbon. Maximum adsorption capacities of carbonized sewage sludge (CSWS and activated sewage sludge (ASWS were found as 7.413 mg g-1 and 9.376 mg g-1 for 100 mg L-1 dye solution, whereas commercial activated carbon had a capacity of 11.561 mg g-1. Freundlich and Langmuir isotherms were used to explain the adsorption mechanism together with pseudo-first-order and pseudo-second-order kinetic models. Langmuir isotherm, which had adsorption capacities of 34.60 mg g-1 (CSWS and 72.99 mg g-1 (ASWS, provided better fit to the equilibrium data than that of Freundlich isotherm. Pseudo second-order, model which had adsorption capacities of 7.451 mg g-1 (CSWS and 9.319 mg g-1 (ASWS, was very favorable to explain the adsorption kinetics of the dye with high regression coefficients.

  2. 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

  3. 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 ...

  4. Anaerobic digestion of sewage sludge: French inventory and state of the art; La methanisation des boues d'epuration urbaines. Etat des lieux en France et etat de l'art

    Energy Technology Data Exchange (ETDEWEB)

    Reverdy, A.L.; Dieude-Fauvel, E.; Baudez, J.C. [Institut national de recherche en sciences et technologies pour l' environnement et l' agriculture - Irstea, Centre de Clermont-Ferrand, Unite de recherches TSCF, Les Palaquins, 03150 Montoldre (France); Ferstler, V. [MEEDDM - DEB, Grande Arche, Paroi Sud, 92055 La Defense Cedex (France)

    2012-07-01

    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{sub 4}), carbon dioxide (CO{sub 2}) and water (H{sub 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)

  5. Optimisation of sewage sludge anaerobic digestion through co-digestion with OFMSW: Effect of collection system and particle size

    Energy Technology Data Exchange (ETDEWEB)

    Silvestre, Gracia [IRTA, GIRO Joint Research Unit IRTA-UPC, Torre Marimon, Barcelona (Spain); Ainia, Departamento de Medio Ambiente, Bioenergía e Higiene Industrial, Paterna, Valencia (Spain); Bonmatí, August [IRTA, GIRO Joint Research Unit IRTA-UPC, Torre Marimon, Barcelona (Spain); Fernández, Belén, E-mail: belen.fernandez@irta.cat [IRTA, GIRO Joint Research Unit IRTA-UPC, Torre Marimon, Barcelona (Spain)

    2015-09-15

    Highlights: • Methane production rate increased between 56% and 208% during OFMSW–SS codigestion. • The OFMSW particle size reduction from 20 to 8 mm did not affect the methane yield. • OFMSW–SS codigestion promoted β-oxidation and acetoclastic methanogenic activity. • The evolution of specific activity was a feasible tool to control the process. - Abstract: The effect of organic fraction of municipal solid waste (OFMSW) loading rate and particulate size on the sewage sludge (SS) mesophilic anaerobic co-digestion was assessed in continuous stirred tank reactor at hydraulic retention time of 20 days. The SS–OFMSW mixture composed by 54% of the volatile solids fed (inlet-VS), at OLR of 3.1 kg{sub COD} m{sup −3} d{sup −1} (1.9 kg{sub VS} m{sup −3} d{sup −1}), showed the highest increment on the volumetric methane production and yield of +200% and +59% respectively, under stable conditions. The effect of particulate size was assessed with the same mixture and same operational conditions but reducing the OFMSW particulate size from 20 mm to 8 mm with the aim to improve the hydrolysis step, but the results showed any influence in the OFMSW particulate size range analysed. In addition, specific biomass activity was assessed at the end of each co-digestion period. Results showed that OFMSW promoted β-oxidation syntrophic acetogens and the acetoclastic methanogens activity; although the last increase of the OFMSW percentage (from 47% to 54% inlet-VS) affected negatively the specific substrate activity, but not inhibitory effect was observed. Therefore, the results obtained in the continuous experiment could be related with some inhibitory or toxic effect and not due to hydrolysis limitation. The specific biomass activity test was demonstrated to be an interesting tool to evaluate and control the co-digestion process, especially when conventional parameters did not explain the behaviour of the biological system.

  6. 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

  7. Fate of antibiotic resistance bacteria and genes during enhanced anaerobic digestion of sewage sludge by microwave pretreatment.

    Science.gov (United States)

    Tong, Juan; Liu, Jibao; Zheng, Xiang; Zhang, Junya; Ni, Xiaotang; Chen, Meixue; Wei, Yuansong

    2016-10-01

    The fate of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) were investigated during the sludge anaerobic digestion (AD) with microwave-acid (MW-H), microwave (MW) and microwave-H2O2-alkaline (MW-H2O2) pretreatments. Results showed that combined MW pretreatment especially for the MW-H pretreatment could efficiently reduce the ARB concentration, and most ARG concentrations tended to attenuate during the pretreatment. The subsequent AD showed evident removal of the ARB, but most ARGs were enriched after AD. Only the concentration of tetX kept continuous declination during the whole sludge treatment. The total ARGs concentration showed significant correlation with 16S rRNA during the pretreatment and AD. Compared with unpretreated sludge, the AD of MW and MW-H2O2 pretreated sludge presented slightly better ARB and ARGs reduction efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. 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.

  9. 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.)

  10. Performance evaluation of the sulfur-redox-reaction-activated up-flow anaerobic sludge blanket and down-flow hanging sponge anaerobic/anoxic sequencing batch reactor system for municipal sewage treatment.

    Science.gov (United States)

    Hatamoto, Masashi; Ohtsuki, Kota; Maharjan, Namita; Ono, Shinya; Dehama, Kazuya; Sakamoto, Kenichi; Takahashi, Masanobu; Yamaguchi, Takashi

    2016-03-01

    A sulfur-redox-reaction-activated up-flow anaerobic sludge blanket (UASB) and down-flow hanging sponge (DHS) system, combined with an anaerobic/anoxic sequencing batch reactor (A2SBR), has been used for municipal sewage treatment for over 2 years. The present system achieved a removal rate of 95±14% for BOD, 74±22% for total nitrogen, and 78±25% for total phosphorus, including low water temperature conditions. Sludge conversion rates during the operational period were 0.016 and 0.218 g-VSS g-COD-removed(-1) for the UASB, and DHS, respectively, which are similar to a conventional UASB-DHS system, which is not used of sulfur-redox-reaction, for sewage treatment. Using the sulfur-redox reaction made advanced treatment of municipal wastewater with minimal sludge generation possible, even in winter. Furthermore, the occurrence of a unique phenomenon, known as the anaerobic sulfur oxidation reaction, was confirmed in the UASB reactor under the winter season. Copyright © 2016. Published by Elsevier Ltd.

  11. Treatment of high-strength synthetic sewage in a laboratory-scale upflow anaerobic sludge bed (UASB) with aerobic activated sludge (AS) post-treatment.

    Science.gov (United States)

    Banihani, Qais H; Field, Jim A

    2013-01-01

    Performance of a combined system up-flow anaerobic sludge blanket (UASB) followed by aerobic treatment activated sludge (AS) for removal of carbonaceous and nitrogenous contaminants at an average temperature of 25°C was investigated. The combined system was fed with high strength synthetic sewage having chemical oxygen demand (COD) of 2500 mg L(-1). The organic loading rate (OLR) of the UASB reactor was increased gradually from 1.1 to 3.8 gCOD L(r) (-1) d(-1). At steady state condition, the UASB reactor achieved removal efficiency up to 83.5% of total COD (COD(tot)), 74.0% of volatile fatty acid (VFA) and 94.0% of protein. The combined system performed an excellent organic removal pushing the overall removal efficiency of COD(tot), VFA and protein to 91.0%, 99.9% and 98.2%, respectively. When the OLR of the UASB increased to 4.4 g COD L(r) (-1) d(-1), the UASB was overloaded and; thus, its effluent quality deteriorated. In respect to nitrogen removal, both partial nitrification and complete nitrification took place in aerobic post-treatment. When the dissolved oxygen (DO) concentration was >2.0 mg L(-1), complete nitrification (period B) occurred with an average nitrification efficiency of 96.2%. The partial nitrification occurred due to high OLR to AS during the overloading event (period A) and when DO concentration was <2.0 mg L(-1) (period C). The maximum accumulated nitrite concentration in periods A, B and C were 90.0, 0.9 and 75.8 mg NO(-) (2) -N L(-1), respectively. The nitrogen balance results of periods A and C indicated that there was a discrepancy between the amount of ammonium nitrogen removed and the amount of oxidized nitrogen formed. This suggests the occurrence of simultaneous nitrification/denitrification (SND) in aerobic post-treatment.

  12. 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

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

    Science.gov (United States)

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

    2017-04-01

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

  14. Preliminary experimental results of Sewage Sludge (SS) Co-digestion with Palm Oil Mill Effluent (POME) for Enhanced Biogas Production in Laboratory Scale Anaerobic Digester

    International Nuclear Information System (INIS)

    Sivasankari, R; Kumaran, P; Normanbhay, Saifuddin; Shamsuddin, Abd Halim

    2013-01-01

    An investigation on the feasibility of co-digesting Sewage Sludge with Palm Oil Mill Effluent for enhancing the biogas production and the corresponding effect of the co-digestion substrate ratio on the biogas production has been evaluated. Anaerobic co-digestion of POME with SS was performed at ratios of 100:0, 70:30, 60:40 and 0:100 to find the optimum blend required for enhanced waste digestion and biogas production. Single stage batch digestion was carried out for 12 days in a laboratory scale anaerobic digester. Co-digestion of sludge's at the 70:30 proportion resulted in optimal COD and C: N ratio which subsequently recorded the highest performance with regards to biogas production at 28.1 L's compared to the 1.98 L's of biogas produced from digestion of SS alone. From the results obtained, it is evident that co-digestion of POME and SS is an attractive option to be explored for enhancement of biogas production in anaerobic digesters.

  15. 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.

  16. Full-scale production of VFAs from sewage sludge by anaerobic alkaline fermentation to improve biological nutrients removal in domestic wastewater.

    Science.gov (United States)

    Liu, He; Han, Peng; Liu, Hongbo; Zhou, Guangjie; Fu, Bo; Zheng, Zhiyong

    2018-07-01

    A full-scale project of thermal-alkaline pretreatment and alkaline fermentation of sewage sludge was built to produce volatile fatty acids (VFAs) which was then used as external carbon source for improving biological nitrogen and phosphorus removals (BNPR) in wastewater plant. Results showed this project had efficient and stable performances in VFA production, sludge reduce and BNPR. Hydrolysis rate in pretreatment, VFAs yield in fermentation and total VS reduction reached 68.7%, 261.32 mg COD/g VSS and 54.19%, respectively. Moreover, fermentation liquid with VFA presented similar efficiency as acetic acid in enhancing BNPR, obtaining removal efficiencies of nitrogen and phosphorus up to 72.39% and 89.65%, respectively. Finally, the project also presented greater economic advantage than traditional processes, and the net profits for VFAs and biogas productions are 9.12 and 3.71 USD/m 3 sludge, respectively. Long-term operation indicated that anaerobic alkaline fermentation for VFAs production is technically and economically feasible for sludge carbon recovery. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. 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)

  18. Mesophilic anaerobic co-digestion of the organic fraction of municipal solid waste with the liquid fraction from hydrothermal carbonization of sewage sludge.

    Science.gov (United States)

    De la Rubia, M A; Villamil, J A; Rodriguez, J J; Borja, R; Mohedano, A F

    2018-06-01

    In the present study, the influence of substrate pre-treatment (grinding and sieving) on batch anaerobic digestion of the organic fraction of municipal solid waste (OFMSW) was first assessed, then followed by co-digestion experiments with the liquid fraction from hydrothermal carbonization (LFHTC) of dewatered sewage sludge (DSS). The methane yield of batch anaerobic digestion after grinding and sieving (20 mm diameter) the OFMSW was considerably higher (453 mL CH 4 STP g -1 VS added ) than that of untreated OFMSW (285 mL CH 4 STP g -1 VS added ). The modified Gompertz model adequately predicted process performance. The maximum methane production rate, R m , for ground and sieved OFMSW was 2.4 times higher than that of untreated OFMSW. The anaerobic co-digestion of different mixtures of OFMSW and LFHTC of DSS did not increase the methane yield above that of the anaerobic digestion of OFMSW alone, and no synergistic effects were observed. However, the co-digestion of both wastes at a ratio of 75% OFMSW-25% LFHTC provides a practical waste management option. The experimental results were adequately fitted to a first-order kinetic model showing a kinetic constant virtually independent of the percentage of LFHTC (0.52-0.56 d -1 ) and decreasing slightly for 100% LFHTC (0.44 d -1 ). Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. 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

  20. 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)

  1. 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 ...

  2. 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

  3. Post-anaerobic digestion thermal hydrolysis of sewage sludge and food waste: Effect on methane yields, dewaterability and solids reduction.

    Science.gov (United States)

    Svensson, Kine; Kjørlaug, Oda; Higgins, Matthew J; Linjordet, Roar; Horn, Svein J

    2018-04-01

    Post-anaerobic digestion (PAD) treatment technologies have been suggested for anaerobic digestion (AD) to improve process efficiency and assure hygenization of organic waste. Because AD reduces the amount of organic waste, PAD can be applied to a much smaller volume of waste compared to pre-digestion treatment, thereby improving efficiency. In this study, dewatered digestate cakes from two different AD plants were thermally hydrolyzed and dewatered, and the liquid fraction was recirculated to a semi-continuous AD reactor. The thermal hydrolysis was more efficient in relation to methane yields and extent of dewaterability for the cake from a plant treating waste activated sludge, than the cake from a plant treating source separated food waste (SSFW). Temperatures above 165 °C yielded the best results. Post-treatment improved volumetric methane yields by 7% and the COD-reduction increased from 68% to 74% in a mesophilic (37 °C) semi-continuous system despite lowering the solid retention time (from 17 to 14 days) compared to a conventional system with pre-treatment of feed substrates at 70 °C. Results from thermogravimetric analysis showed an expected increase in maximum TS content of dewatered digestate cake from 34% up to 46% for the SSFW digestate cake, and from 17% up to 43% in the sludge digestate cake, after the PAD thermal hydrolysis process (PAD-THP). The increased dewatering alone accounts for a reduction in wet mass of cake leaving the plant of 60% in the case of sludge digestate cake. Additionaly, the increased VS-reduction will contribute to further reduce the mass of wet cake. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. 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

  5. Impact of trace element additives on anaerobic digestion of sewage sludge with in-situ carbon dioxide sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Linville, Jessica L.; Shen, Yanwen; Schoene, Robin P.; Nguyen, Maximilian; Urgun-Demirtas, Meltem; Snyder, Seth W.

    2016-09-01

    Anaerobic digestion (AD) of sludge at wastewater treatment plants can benefit from addition of essential trace metals such as iron, nickel and cobalt to increase biogas production for utilization in combined heat and power systems, fed into natural gas pipelines or as a vehicle fuel. This study evaluated the impact and benefits of Ni/Co and olivine addition to the digester at mesophilic temperatures. These additions supplement previously reported research in which iron-rich olivine (MgSiO4) was added to sequester CO2 in-situ during batch AD of sludge. Trace element addition has been shown to stimulate and stabilize biogas production and have a synergistic effect on the mineral carbonation process. AD with 5% w/v olivine and 1.5 mg/L Ni/Co addition had a 17.3% increase in methane volume, a 6% increase in initial exponential methane production rate and a 56% increase in methane yield (mL CH4/g CODdegraded) compared to the control due to synergistic trace element and olivine addition while maintaining 17.7% CO2 sequestration from olivine addition. Both first-order kinetic modeling and response surface methodology modeling confirmed the combined benefit of the trace elements and olivine addition. These results were significantly higher than previously reported results with olivine addition alone [1].

  6. Research on the influence of anaerobic stabilization of various dairy sewage sludge on biodegradation of polycyclic aromatic hydrocarbons PAHs with the use of effective microorganisms

    International Nuclear Information System (INIS)

    Boruszko, Dariusz

    2017-01-01

    Sewage sludge was taken from a dairy WWTP belonging to Mlekovita Cooperative in Wysokie Mazowieckie. There were excess sludge, flotation sludge and a mixture of excess and flotation sludge from pre-treatment of dairy sewage. The initial content of 16 PAHs in excess sludge before fermentation was approximately 689 µg·kg −1 in dry mass, whereas in post-flotation sludge (which constituted around 30% of raw sludge) it was approximately 95 µg·kg −1 in dry mass. A mixture of excess and flotation sludge had the content of 497,7 µg·kg −1 in dry mass. Through comparison of particular hydrocarbons content in raw sewage sludge to the total PAHs content, it was shown that tricyclic compounds, which constituted 46,3% of the PAHs sum (excess sludge), and tetracyclic compounds, which constituted 60,0% of the PAHs sum (flotation sludge), were the dominating fractions. In the sludge subjected to fermentation in reactors with mixed sludge and surplus activated sludge, the general trend of the course of changes in concentrations of PAHs was similar. Both in the sludge inoculated with EM and in that not inoculated with EM, a significant increase in the total PAHs contents was observed in the first fermentation phase (acidic fermentation) after 7 days of the process. Addition of EM into the sludge did not prevent the PAHs release, and therefore higher concentrations of PAHs sum were recorded during the hydrolysis stage than in sludge before fermentation. A decrease in the sum of PAHs was observed after 2 weeks of fermentation in relation to the quantity observed after 1 week of fermentation (except from post-flotation sludge). In the following weeks, there was further decrease in the concentration of the 16 PAHs sum in all sludge types. However, in sludge without EM inoculation, it was lower than in sludge with EM inoculation. The loss of the majority of tested hydrocarbons was reported in the final phase of fermentation. - Highlights: • The influence of applying

  7. Research on the influence of anaerobic stabilization of various dairy sewage sludge on biodegradation of polycyclic aromatic hydrocarbons PAHs with the use of effective microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Boruszko, Dariusz, E-mail: d.boruszko@pb.edu.pl

    2017-05-15

    Sewage sludge was taken from a dairy WWTP belonging to Mlekovita Cooperative in Wysokie Mazowieckie. There were excess sludge, flotation sludge and a mixture of excess and flotation sludge from pre-treatment of dairy sewage. The initial content of 16 PAHs in excess sludge before fermentation was approximately 689 µg·kg{sup −1} in dry mass, whereas in post-flotation sludge (which constituted around 30% of raw sludge) it was approximately 95 µg·kg{sup −1} in dry mass. A mixture of excess and flotation sludge had the content of 497,7 µg·kg{sup −1} in dry mass. Through comparison of particular hydrocarbons content in raw sewage sludge to the total PAHs content, it was shown that tricyclic compounds, which constituted 46,3% of the PAHs sum (excess sludge), and tetracyclic compounds, which constituted 60,0% of the PAHs sum (flotation sludge), were the dominating fractions. In the sludge subjected to fermentation in reactors with mixed sludge and surplus activated sludge, the general trend of the course of changes in concentrations of PAHs was similar. Both in the sludge inoculated with EM and in that not inoculated with EM, a significant increase in the total PAHs contents was observed in the first fermentation phase (acidic fermentation) after 7 days of the process. Addition of EM into the sludge did not prevent the PAHs release, and therefore higher concentrations of PAHs sum were recorded during the hydrolysis stage than in sludge before fermentation. A decrease in the sum of PAHs was observed after 2 weeks of fermentation in relation to the quantity observed after 1 week of fermentation (except from post-flotation sludge). In the following weeks, there was further decrease in the concentration of the 16 PAHs sum in all sludge types. However, in sludge without EM inoculation, it was lower than in sludge with EM inoculation. The loss of the majority of tested hydrocarbons was reported in the final phase of fermentation. - Highlights: • The influence of

  8. Optimization and microbial community analysis of anaerobic co-digestion of food waste and sewage sludge based on microwave pretreatment.

    Science.gov (United States)

    Zhang, Junya; Lv, Chen; Tong, Juan; Liu, Jianwei; Liu, Jibao; Yu, Dawei; Wang, Yawei; Chen, Meixue; Wei, Yuansong

    2016-01-01

    The effects of microwave pretreatment (MW) on co-digestion of food waste (FW) and sewage sludge (SS) have never been investigated. In this study, a series of mesophilic biochemical methane potential (BMP) tests were conducted to determine the optimized ratio of FW and SS based on MW, and the evolution of bacterial and archaeal community was investigated through high-throughput sequencing method. Results showed that the optimized ratio was 3:2 for co-digestion of FW and SS based on MW, and the methane production was 316.24 and 338.44mLCH4/gVSadded for MW-FW and MW-SS, respectively. The MW-SS was superior for methane production compared to MW-FW, in which accumulation of propionic acid led to the inhibition of methanogenesis. Proteiniborus and Parabacteroides were responsible for proteins and polysaccharides degradation for all, respectively, while Bacteroides only dominated in co-digestion. Methanosphaera dominated in MW-FW at the active methane production phase, while it was Methanosarcina in MW-SS and mono-SS. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. 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)

  10. 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...

  11. 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.

  12. Anaerobic sewage treatment in a one-stage UASB reactor and a combined UASB Digester system

    NARCIS (Netherlands)

    Mahmoud, N.A.; Zeeman, G.; Gijzen, H.J.; Lettinga, G.

    2004-01-01

    The treatment of sewage at 15°C was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-Digester system. The latter consists of a UASB reactor complemented with a digester for mutual sewage treatment and sludge stabilisation. The UASB reactor was operated at a

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

    Science.gov (United States)

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

    2017-01-01

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

  14. Process performance assessment of advanced anaerobic digestion of sewage sludge including sequential ultrasound-thermal (55 °C) pre-treatment.

    Science.gov (United States)

    Neumann, Patricio; Barriga, Felipe; Álvarez, Claudia; González, Zenón; Vidal, Gladys

    2018-03-15

    The aim of this study was to evaluate the performance and digestate quality of advanced anaerobic digestion of sewage sludge including sequential ultrasound-thermal (55 °C) pre-treatment. Both stages of pre-treatment contributed to chemical oxygen demand (COD) solubilization, with an overall factor of 11.4 ± 2.2%. Pre-treatment led to 19.1, 24.0 and 29.9% increased methane yields at 30, 15 and 7.5 days solid retention times (SRT), respectively, without affecting process stability or accumulation of intermediates. Pre-treatment decreased up to 4.2% water recovery from the digestate, but SRT was a more relevant factor controlling dewatering. Advanced digestion showed 2.4-3.1 and 1.5 logarithmic removals of coliforms and coliphages, respectively, and up to a 58% increase in the concentration of inorganics in the digestate solids compared to conventional digestion. The COD balance of the process showed that the observed increase in methane production was proportional to the pre-treatment solubilization efficiency. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. 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)

  16. 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

  17. Anaerobic treatment of sludge: focusing on reduction of LAS concentration in sludge

    DEFF Research Database (Denmark)

    Haagensen, Frank; Mogensen, Anders Skibsted; Angelidaki, Irini

    2002-01-01

    Anaerobic degradation of linear alkylbenzene sulfonates (LAS) was tested in continuous stirred tank reactors (CSTR). LAS12 was used as a model compound and was spiked on sewage sludge. The experiments clearly showed that transformation of LAS12 occurred under anaerobic conditions. The degree...

  18. 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.

  19. 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)

  20. 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).

  1. 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.

  2. 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

  3. 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...

  4. The effect of sludge recirculation rate on a UASB-digester treating domestic sewage at 15 °C

    NARCIS (Netherlands)

    Zhang, L.; Hendrickx, T.L.G.; Kampman, C.; Zeeman, G.; Temmink, B.G.; Weiguang Li,; Buisman, C.J.N.

    2012-01-01

    The anaerobic treatment of low strength domestic sewage at low temperature is an attractive and important topic at present. The upflow anaerobic sludge bed (UASB)-digester system is one of the anaerobic systems to challenge low temperature and concentrations. The effect of sludge recirculation rate

  5. 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.

  6. 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.

  7. 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

  8. 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,.

  9. 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

  10. 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.

  11. 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)

  12. Microbial community composition of a down-flow hanging sponge (DHS) reactor combined with an up-flow anaerobic sludge blanket (UASB) reactor for the treatment of municipal sewage.

    Science.gov (United States)

    Kubota, Kengo; Hayashi, Mikio; Matsunaga, Kengo; Iguchi, Akinori; Ohashi, Akiyoshi; Li, Yu-You; Yamaguchi, Takashi; Harada, Hideki

    2014-01-01

    The microbial community composition of a down-flow hanging sponge (DHS) reactor in an up-flow anaerobic sludge blanket (UASB)-DHS system used for the treatment of municipal sewage was investigated. The clone libraries showed marked differences in microbial community composition at different reactor heights and in different seasons. The dominant phylotypes residing in the upper part of the reactor were likely responsible for removing organic matters because a significant reduction in organic matter in the upper part was observed. Quantification of the amoA genes revealed that the proportions of ammonia oxidizing bacteria (AOB) varied along the vertical length of the reactor, with more AOB colonizing the middle and lower parts of the reactor than the top of the reactor. The findings indicated that sewage treatment was achieved by a separation of microbial habitats responsible for organic matter removal and nitrification in the DHS reactor. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. 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)

  14. 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.

  15. 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

  16. 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.

  17. 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...

  18. Depth-resolved microbial community analyses in the anaerobic co-digester of dewatered sewage sludge with food waste.

    Science.gov (United States)

    Xu, Rui; Yang, Zhao-Hui; Zheng, Yue; Zhang, Hai-Bo; Liu, Jian-Bo; Xiong, Wei-Ping; Zhang, Yan-Ru; Ahmad, Kito

    2017-11-01

    This study evaluated the impacts of FW addition on co-digestion in terms of microbial community. Anaerobic co-digestion (AcoD) reactors were conducted at gradually increased addition of food waste (FW) from 0 to 4kg-VSm -3 d -1 for 220days. Although no markable acidification was found at an OLR of 4kg-VSm -3 d -1 , the unhealthy operation was observed in aspect of an inhibited methane yield (185mLg -1 VS added ), which was restricted by 40% when compared with its peak value. Deterioration of digestion process was timely indicated by the dramatic decrease of archaeal population and microbial biodiversity. Furthermore, the cooperation network showed a considerable number of rare species (<1%) were strongly correlated with methane production, which were frequently overlooked due to the limits of detecting resolution or analysis methods before. Advances in the analysis of sensitive microbial community enable us to detect the early disturbances in AcoD reactors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. 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.

  20. 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.)

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

    Directory of Open Access Journals (Sweden)

    Suschka Jan

    2014-07-01

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

  2. 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.

  3. Co-existence of Anaerobic Ammonium Oxidation Bacteria and Denitrifying Anaerobic Methane Oxidation Bacteria in Sewage Sludge: Community Diversity and Seasonal Dynamics

    DEFF Research Database (Denmark)

    Xu, Sai; Lu, Wenjing; Mustafa, Muhammad Farooq

    2017-01-01

    Anaerobic ammonium oxidation (ANAMMOX) and denitrifying anaerobic methane oxidation (DAMO) have been recently discovered as relevant processes in the carbon and nitrogen cycles of wastewater treatment plants. In this study, the seasonal dynamics of ANAMMOX and DAMO bacterial community structures......, and an unknown cluster was primarily detected in autumn and winter. Similar patterns of seasonal variation in the community structure of DAMO bacteria were also observed. Group B was the dominant in spring and summer, whereas in autumn and winter, group A and group B presented almost the same proportion...

  4. 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....

  5. 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

  6. 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)

  7. Viscosity evolution of anaerobic granular sludge

    NARCIS (Netherlands)

    Pevere, A.; Guibaud, G.; Hullebusch, van E.D.; Lens, P.N.L.; Baudu, M.

    2006-01-01

    The evolution of the apparent viscosity at steady shear rate of sieved anaerobic granular sludge (20¿315 ¿m diameter) sampled from different full-scale anaerobic reactors was recorded using rotation tests. The ¿limit viscosity¿ of sieved anaerobic granular sludge was determined from the apparent

  8. Low intensity surplus activated sludge pretreatment before anaerobic digestion

    Directory of Open Access Journals (Sweden)

    Suschka Jan

    2017-12-01

    Full Text Available Sewage sludge (municipal, or industrial treatment is still a problem in so far that it is not satisfactorily resolved in terms of cost and final disposal. Two common forms of sludge disposal are possible; the first being direct disposal on land (including agriculture and the second being incineration (ash production, although neither of these methods are universally applied. Simplifying the issue, direct sludge disposal on land is seldom applied for sanitary and environmental reasons, while incineration is not popular for financial (high costs reasons. Very often medium and large wastewater treatment plants apply anaerobic digestion for sludge hygiene principles, reducing the amount to be disposed and for biogas (energy production. With the progress in sewage biological treatment aiming at nutrient removal, primary sludge has been omitted in the working processes and only surplus activated sludge requires handling. Anaerobic digestion of waste activated sludge (WAS is more difficult due to the presence of microorganisms, the decomposition of which requires a relatively long time for hydrolysis. In order to upgrade the hydrolysis effects, several different pre-treatment processes have already been developed and introduced. The additional pre-treatment processes applied are aimed at residual sludge bulk mass minimization, shortening of the anaerobic digestion process or higher biogas production, and therefore require additional energy. The water-energy-waste Nexus (treads of of the benefits and operational difficulties, including energy costs are discussed in this paper. The intensity of pre-treatment processes to upgrade the microorganism’s hydrolysis has crucial implications. Here a low intensity pre-treatment process, alkalisation and hydrodynamic disintegration - hybrid process - were presented in order to achieve sufficient effects of WAS anaerobic digestion. A sludge digestion efficiency increase expressed as 45% biogas additional

  9. Pilot tests in enhanced ultrasonic disintegration of sewage sludge; Pilotversuche zur Intensivierung der Schlammfaulung durch Klaerschlammdesintegration mit Ultraschall

    Energy Technology Data Exchange (ETDEWEB)

    Nickel, K.; Tiehm, A.; Neis, U. [Technische Univ. Hamburg-Harburg, Hamburg (Germany). Arbeitsbereich Abwasserwirtschaft

    1999-07-01

    The work has the objective to optimize ultrasonic disintegration of sewage sludge in permant routine operation. Anaerobic degradation of disintegrated crude and excess sludge was investigated on a pilot scale at a municipal sewage treatment plant. (orig.) [German] Ziel dieser Arbeit ist die Optimierung der Klaerschlammdesintegration mit Ultraschall im praktischen Dauerbetrieb. Der anaerobe Abbau von desintegriertem Roh- und Ueberschussschlamm wurde im Pilotmassstab vor Ort auf einer kommunalen Klaeranlage untersucht. (orig.)

  10. Integrated anaerobic and aerobic treatment of sewage

    NARCIS (Netherlands)

    Wang, K.

    1994-01-01

    This thesis describes results of investigations dealing with sequential concept of anaerobic-aerobic treatment of municipal wastewater. The main purposes of the study were 1) to develop a proper anaerobic hydrolytic pretreatment unit, consisting of a Hydrolysis Upflow Sludge Bed (HUSB-)

  11. 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.

  12. 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.

  13. 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

  14. Application of Anaerobic Digestion Model No. 1 for simulating anaerobic mesophilic sludge digestion

    International Nuclear Information System (INIS)

    Mendes, Carlos; Esquerre, Karla; Matos Queiroz, Luciano

    2015-01-01

    Highlights: • The behavior of a anaerobic reactor was evaluated through modeling. • Parametric sensitivity analysis was used to select most sensitive of the ADM1. • The results indicate that the ADM1 was able to predict the experimental results. • Organic load rate above of 35 kg/m 3 day affects the performance of the process. - Abstract: Improving anaerobic digestion of sewage sludge by monitoring common indicators such as volatile fatty acids (VFAs), gas composition and pH is a suitable solution for better sludge management. Modeling is an important tool to assess and to predict process performance. The present study focuses on the application of the Anaerobic Digestion Model No. 1 (ADM1) to simulate the dynamic behavior of a reactor fed with sewage sludge under mesophilic conditions. Parametric sensitivity analysis is used to select the most sensitive ADM1 parameters for estimation using a numerical procedure while other parameters are applied without any modification to the original values presented in the ADM1 report. The results indicate that the ADM1 model after parameter estimation was able to predict the experimental results of effluent acetate, propionate, composites and biogas flows and pH with reasonable accuracy. The simulation of the effect of organic shock loading clearly showed that an organic shock loading rate above of 35 kg/m 3 day affects the performance of the reactor. The results demonstrate that simulations can be helpful to support decisions on predicting the anaerobic digestion process of sewage sludge

  15. Application of Anaerobic Digestion Model No. 1 for simulating anaerobic mesophilic sludge digestion

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, Carlos, E-mail: carllosmendez@gmail.com; Esquerre, Karla, E-mail: karlaesquerre@ufba.br; Matos Queiroz, Luciano, E-mail: lmqueiroz@ufba.br

    2015-01-15

    Highlights: • The behavior of a anaerobic reactor was evaluated through modeling. • Parametric sensitivity analysis was used to select most sensitive of the ADM1. • The results indicate that the ADM1 was able to predict the experimental results. • Organic load rate above of 35 kg/m{sup 3} day affects the performance of the process. - Abstract: Improving anaerobic digestion of sewage sludge by monitoring common indicators such as volatile fatty acids (VFAs), gas composition and pH is a suitable solution for better sludge management. Modeling is an important tool to assess and to predict process performance. The present study focuses on the application of the Anaerobic Digestion Model No. 1 (ADM1) to simulate the dynamic behavior of a reactor fed with sewage sludge under mesophilic conditions. Parametric sensitivity analysis is used to select the most sensitive ADM1 parameters for estimation using a numerical procedure while other parameters are applied without any modification to the original values presented in the ADM1 report. The results indicate that the ADM1 model after parameter estimation was able to predict the experimental results of effluent acetate, propionate, composites and biogas flows and pH with reasonable accuracy. The simulation of the effect of organic shock loading clearly showed that an organic shock loading rate above of 35 kg/m{sup 3} day affects the performance of the reactor. The results demonstrate that simulations can be helpful to support decisions on predicting the anaerobic digestion process of sewage sludge.

  16. 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)

  17. Anaerobic granular sludge and biofilm reactors

    DEFF Research Database (Denmark)

    Skiadas, Ioannis V.; Gavala, Hariklia N.; Schmidt, Jens Ejbye

    2003-01-01

    by the immobilization of the biomass, which forms static biofilms, particle-supported biofilms, or granules depending on the reactor's operational conditions. The advantages of the high-rate anaerobic digestion over the conventional aerobic wastewater treatment methods has created a clear trend for the change......-rate anaerobic treatment systems based on anaerobic granular sludge and biofilm are described in this chapter. Emphasis is given to a) the Up-flow Anaerobic Sludge Blanket (UASB) systems, b) the main characteristics of the anaerobic granular sludge, and c) the factors that control the granulation process...

  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. 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)

  1. 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.

  2. Anaerobic treatment of slaughterhouse waste using a flocculant sludge UASB reactor. [Upflow Anaerobic Sludge Blanket

    Energy Technology Data Exchange (ETDEWEB)

    Sayed, S.; de Zeeuw, W.; Lettinga, G.

    1984-01-01

    This study was carried out to assess the feasibility of using the upflow anaerobic sludge blanket (UASB) process for the one-step anaerobic treatment of slaughterhouse waste, which contains approximately 50% insoluble suspended COD. Batch experiments, as well as continuous experiments, were conducted. The continuous experiments were carried out in a 30 cubic m UASB pilot-plant with digested sewage sludge from the municipal sewage treatment plant of Ede, The Netherlands (Ede-2 sludge), used as seed. Initially the UASB pilot-plant was operated at a temperature of 30 degrees C, but, 20 weeks after the start-up, the temperature was reduced to 20 degrees C, because application of the process at this lower temperature might be quite attractive for economic reasons. The process can be started up at an organic space load of 1 kg COD/m/sup 3/ day (sludge load, 0.11 kg/COD kg VSSday) and at a liquid detention time of 35 h at a process temperature of 30 degrees C. Once started up, the system can satisfactorily handle organic space loads up to 3.5 kg COD/m/sup 3/ day at a liquid detention time of 8 hours at temperatures as low as 20 degrees C. A treatment efficiency up to 70% on a COD tot basis, 90% on a COD sol basis and 95% on a BOD5 sol basis was smoothly approached. Temporary shock loads up to 7 kg COD/m/sup 3/ day during the daytime at a liquid detention time of 5 h can well be accommodated provided such a shock load is followed by a period of underloading, e.g. at night. The methane yield amounted to 0.28 NM/sup 3/ per kilogram of COD removed: the methane content of the biogas from the wastewater varied between 65 and 75%. 19 references.

  3. 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

  4. 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...

  5. 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.

  6. 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...

  7. 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 ...

  8. Anaerobic digestion of industrial activated aerobic sludge

    International Nuclear Information System (INIS)

    Goodloe, J.G.; Roberts, R.S.

    1990-04-01

    The Tennessee Eastman Company manufactures a variety of organic chemicals, plastics and fibers at their Kingsport Tennessee Facility. The wastewater generated during the manufacture of these compounds is currently treated using an activated sludge process. The objective of the project is to evaluate the economic potential of an anaerobic digestion process to convert industrial sludge at the Tennessee Eastman Company into biogas. The evaluation will require collection and analysis of experimental data on the anaerobic digestion of industrial sludge obtained from Kingsport. Although the experiments will be conducted using Tennessee Eastman sludge, these results should be also generally applicable to similar industrial sludge

  9. 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)

  10. 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)

  11. 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.

  12. 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....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

  14. 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)

  15. 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.)

  16. 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

  17. 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.

  18. 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

  19. High-solids anaerobic co-digestion of sewage sludge and food waste in comparison with mono digestions: stability and performance.

    Science.gov (United States)

    Dai, Xiaohu; Duan, Nina; Dong, Bin; Dai, Lingling

    2013-02-01

    System stability and performance of high-solids anaerobic co-digestion of dewatered sludge (DS) and food waste (FW) in comparison with mono digestions were investigated. System stability was improved in co-digestion systems with co-substrate acting as a diluting agent to toxic chemicals like ammonia or Na(+). For high-solids digestion of DS, the addition of FW not only improved system stability but also greatly enhanced volumetric biogas production. For high-solids digestion of FW, the addition of DS could reduce Na(+) concentration and help maintain satisfactory stability during the conversion of FW into biogas. System performances of co-digestion systems were mainly determined by the mixing ratios of DS and FW. Biogas production and volatile solids (VSs) reduction in digestion of the co-mixture of DS and FW increased linearly with higher ratios of FW. A kinetic model, which aimed to forecast the performance of co-digestion and to assist reactor design, was developed from long-term semi-continuous experiments. Maximum VS reduction for DS and FW was estimated to be 44.3% and 90.3%, respectively, and first order constant k was found to be 0.17d(-1) and 0.50 d(-1), respectively. Experimental data of co-digestion were in good conformity to the predictions of the model. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. The effect of anaerobic-aerobic and feast-famine cultivation pattern on bacterial diversity during poly-β-hydroxybutyrate production from domestic sewage sludge.

    Science.gov (United States)

    Liu, Changli; Liu, Di; Qi, Yingjie; Zhang, Ying; Liu, Xi; Zhao, Min

    2016-07-01

    The main objective of this work was to investigate the influence of different oxygen supply patterns on poly-β-hydroxybutyrate (PHB) yield and bacterial community diversity. The anaerobic-aerobic (A/O) sequencing batch reactors (SBR1) and feast-famine (F/F) SBR2 were used to cultivate activated sludge to produce PHB. The mixed microbial communities were collected and analyzed after 3 months cultivation. The PHB maximum yield was 64 wt% in SBR1 and 53 wt% in SBR2. Pyrosequencing analysis 16S rRNA gene of two microbial communities indicated there were nine and four bacterial phyla in SBR1 and SBR2, respectively. Specifically, Proteobacteria (36.4 % of the total bacterial community), Actinobacteria (19.7 %), Acidobacteria (14.1 %), Firmicutes (4.4 %), Bacteroidetes (1.7 %), Cyanobacteria/Chloroplast (1.5 %), TM7 (0.8 %), Gemmatimonadetes (0.2 %), and Nitrospirae (0.1 %) were present in SBR1. Proteobacteria (94.2 %), Bacteroidetes (2.9 %), Firmicutes (1.9 %), and Actinobacteria (0.7 %) were present in SBR2. Our results indicated the SBR1 fermentation system was more stable than that of SBR2 for PHB accumulation.

  1. 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.

  2. Sewage characterisation as a tool for the application of anaerobic treatment in Palestine

    International Nuclear Information System (INIS)

    Mahmoud, Nidal; Amarneh, Mohammad Naser; Al-Sa'ed, Rashed; Zeeman, Grietje; Gijzen, Huub; Lettinga, Gatze

    2003-01-01

    Sewage characteristics can be used to select or modify treatment processes. - Adequate knowledge on sewage characteristics is a prerequisite for selection and sizing of anaerobic treatment technologies, i.e. Upflow Anaerobic Sludge Blanket (UASB) systems. Composite sewage samples were collected from three locations in Ramallah/Al-Bireh district and analysed for several chemical and physical parameters, including samples fractionation into soluble, colloidal and suspended. The results revealed that the sewage in the study area is of very high strength. This is attributed to low water consumption, industrial discharges and people's habits resulting in a high specific COD production [gCOD per capita per day (gCOD/c.d)]. Simple model calculations revealed that the process conditions in a one stage UASB reactor should be modified to overcome the sewage high solids content and low temperature during wintertime

  3. 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.

  4. 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

  5. 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.

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

    Science.gov (United States)

    Miodoński, Stanisław

    2017-11-01

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

  7. 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.

  8. 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.

  9. 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.)

  10. 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.

  11. 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)

  12. 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

  13. Comparison and optimization of different processes of mechanical sewage sludge disintegration; Vergleich und Optimierung verschiedener Verfahren der mechanischen Klaerschlammdesintegration

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-07-01

    There are in principle three applications of mechanical sewage sludge disintegration within the framework of sewage treatment, which are briefly dealt with. The organic material released in the course of the disintegration process can be used as a proton donator for denitrification. In the second application, mechanical sludge disintegration improves the sedimentation properties of bulking sludge and scum. In the third application, sewage sludge disintegration enhances the anaerobic degradation behaviour of excess sludge and digester sludge. (orig.) [German] Es gibt drei prinzipielle Einsatzfaelle einer mechanischen Klaerschlammdesintegration im Rahmen des Abwasserreinigungsprozesses, auf die im folgenden kurz eingegangen wird. Das im Zuge der Desintegration freigesetzte organische Material kann als Protonendonator fuer die Denitrifikation verwendet werden. Eine weitere Anwendung der mechanischen Desintegration stellt die Verbesserung der Absetzeigenschaften von Blaeh- und Schwimmschlaemmen dar. Den dritten Einsatzfall der Klaerschlammdesintegration stellt die Verbesserung des anaeroben Abbauverhaltens von Ueberschuss- und Faulschlaemmen dar. (orig.)

  14. 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.

  15. 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

  16. 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.

  17. 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)

  18. 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.

  19. PRESENCE OF HELMINTH EGGS IN SEWAGE SLUDGE FROM CAMPO GRANDE (MS, BRAZIL MUNICIPALITY AFTER ANAEROBIC TREATMENT LEVANTAMENTO DE OVOS DE HELMINTOS EM LODO DE ESGOTO ORIUNDO DE CAMPO GRANDE (MS APÓS TRATAMENTO ANAERÓBICO

    Directory of Open Access Journals (Sweden)

    Juliana Rosa Carrijo

    2008-04-01

    Full Text Available The present study was conducted to evaluate the helminth eggs presence in sewage sludge, previously treated in anerobic digestion process like anaerobic liquid fluid reactor. First of all were evaluated different kinds of materials to choose the best filter which permitted to filter the Taenia saginata eggs. The filter that showed better adaptation was the fine toilet paper one sheet. The helminth eggs were classified for their genera, according to their morphology. The Taenia sp, Trichuris, Dipylidium and Strongyloides were find only in one collect. The number of nematode eggs prevailed on the cestodes. The quantity of helminths eggs found was variable, indicatting complementary treatments process to the sewage sludge. It was concluded that the filter tested was efficient to Taenia sp eggs and to other helminth eggs present in sewage sludge. KEY WORDS: Biossolid, filter, Taenia sp. O presente trabalho avaliou a presença de ovos de helmintos em lodo de esgoto, previamente tratado em sistema de digestão anaeróbia do tipo reator anaeróbio de lodo fluidizado (RALF. Primeiramente testaram-se diferentes tipos de materiais para a escolha do filtro que possibilitasse a passagem de ovos de Taenia saginata. O filtro mais adequado foi o papel higiênico fino, folha única. Classificaram-se os ovos de helmintos por gênero, de acordo com sua morfologia. Encontraram-se ovos de Taenia sp, Trichuris, Dipylidium e

  20. 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.)

  1. 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.

  2. 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.

  3. 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.)

  4. Efeito do retorno de lodo aeróbio sobre as características da biomassa presente em reatores UASB tratando esgoto sanitário Effect of aerobic sludge return on the characteristics of anaerobic biomass present in UASB reactors treating domestic sewage

    Directory of Open Access Journals (Sweden)

    Patrícia Procópio Pontes

    2009-06-01

    Full Text Available O presente trabalho buscou avaliar a influência do retorno do lodo produzido em filtros biológicos percoladores (FBP sobre as características da biomassa em reatores UASB utilizados para o tratamento de esgoto sanitário. Os experimentos foram conduzidos em reatores em escala piloto e em escala de demonstração, sendo que os reatores UASB foram operados com e sem retorno do lodo produzido nos FBP. Os resultados obtidos indicaram uma diminuição no diâmetro das partículas de lodo, durante as fases com retorno de lodo, mas apenas para as amostras de lodo tomadas nos pontos mais altos dos reatores anaeróbios. A estabilidade e a atividade metanogênica específica do lodo anaeróbio praticamente não se modificaram com o retorno de lodo. Conforme esperado, a produção específica de lodo anaeróbio aumentou com o retorno de lodo.This work aimed at evaluating the influence of the return of excess aerobic sludge produced in trickling filters (TF upon the biomass characteristics in UASB reactors used for the treatment of domestic sewage. The experiments were carried out in pilot and demonstration-scale reactors, with the UASB reactors being operated with and without the return of sludge produced in the TF. Smaller sludge particle sizes were observed when the aerobic sludge was returned to the UASB reactor, but only for sludge samples collected in the upper parts of the anaerobic reactors. Sludge stability and specific methanogenic activity were not affected by the return of sludge. As expected, the specific anaerobic sludge production increased with the return of sludge.

  5. 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)

  6. 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 ...

  7. Improvement of anaerobic digestion of sludge

    Energy Technology Data Exchange (ETDEWEB)

    Dohanyos, Michael; Zabranska, Jana; Kutil, Josef; Jenicek, Pavel

    2003-07-01

    Anaerobic digestion improvement can be accomplished by different methods. Besides optimization of process conditions is frequently used pretreatment of input sludge and increase of process temperature. Thermophilic process brings a higher solids reduction and biogas production, the high resistance to foaming, no problems with odour, the higher effect of destroying pathogens and the improvement of the energy balance of the whole treatment plant. Disintegration of excess activated sludge in lysate centrifuge was proved in full-scale conditions causing increase of biogas production. The rapid thermal conditioning of digested sludge is acceptable method of particulate matter disintegration and solubilization. (author)

  8. 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

  9. 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

  10. 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.

  11. 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....

  12. 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...

  13. 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

  14. 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.

  15. 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

  16. An environmental LCA of alternative scenarios of urban sewage sludge treatment and disposal

    Directory of Open Access Journals (Sweden)

    Tarantini Mario

    2007-01-01

    Full Text Available The majority of pollutants that affect wastewater are concentrated by treatment processes in sludge; it is therefore critical to have a suitable evaluation methodology of sludge management options to analyze if pollution is redirected from water to other media, such as air and soil. Life cycle assessment is one of the most widely known and internationally accepted methodologies to compare environmental impacts of processes and systems and to evaluate their sustainability in the entire life cycle. In this study the methodology was applied to assess and compare three scenarios of urban sewage sludge treatment and disposal: sludge anaerobic digestion followed by dedicated incineration, sludge incineration without previous digestion, and sludge anaerobic digestion followed by composting. The potential benefits of spreading the compost to soil were not included in the system boundaries even if, due to its nutrients contents and soil improving features, compost could partially replace the use of commercial products. The study was aimed at finding out the environmental critical points of the treatment alternatives selected and at providing a technical and scientific contribution for further debates with national and local authorities on the environmental optimization of sewage sludge management. Life cycle assessment results confirmed the major contribution of electricity and methane consumption on several environmental impact categories. Incineration contributes more than sludge composting to almost all categories, although the heavy metals content of urban wastewater sludge raises substantial concerns when composted sludge is spread to soil. In this paper the models adopted, the hypotheses assumed and the main findings of the study are presented and discussed. .

  17. 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.

  18. Mesophilic and thermophilic anaerobic digestion of primary and secondary sludge. Effect of pre-treatment at elevated temperature

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Yenal, U.; Skiadas, Ioannis V.

    2003-01-01

    Anaerobic digestion is an appropriate technique for the treatment of sludge before final disposal and it is employed worldwide as the oldest and most important process for sludge stabilization. In general, mesophilic anaerobic digestion of sewage sludge is more widely used compared to thermophilic...... digestion. Furthermore, thermal pre-treatment is suitable for the improvement of stabilization, enhancement of dewatering of the sludge, reduction of the numbers of pathogens and could be realized at relatively low cost especially at low temperatures. The present study investigates (a) the differences...... between mesophilic and thermophilic anaerobic digestion of sludge and (b) the effect of the pretreatment at 70 degreesC on mesophilic and thermophilic anaerobic digestion of primary and secondary sludge. The pretreatment step showed very positive effect on the methane potential and production rate upon...

  19. 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.)

  20. 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.

  1. Fate of antibiotic resistance genes and its drivers during anaerobic co-digestion of food waste and sewage sludge based on microwave pretreatment.

    Science.gov (United States)

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

    2016-10-01

    In this study, anaerobic digestion of mono-SS, MW-SS:FW and SS:MW-FW was investigated to understand the fate of ARGs and its drivers. Anaerobic digestion was effective for the reduction of metal resistance genes (MRGs), and could reduce the abundance of blaOXA-1, sulI and tetG, while sulII in co-digestion and blaTEM and ereA only in MW-SS. ARGs reduction could be partly attributed to the reduction of co-selective pressure from heavy metals reflected by MRGs. However, the abundance of mefA/E, ermB, ermF, tetM and tetX increased significantly. Anaerobic co-digestion, especially for MW-SS, could reduce total ARGs abundance compared with mono-SS, and evolution of bacterial community was the main driver for the fate of ARGs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. 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)

  3. Enhanced dewaterability of sludge during anaerobic digestion with thermal hydrolysis pretreatment: New insights through structure evolution.

    Science.gov (United States)

    Zhang, Jingsi; Li, Ning; Dai, Xiaohu; Tao, Wenquan; Jenkinson, Ian R; Li, Zhuo

    2017-12-19

    Comprehensive insights into the sludge digestate dewaterability were gained through porous network structure of sludge. We measured the evolution of digestate dewaterability, represented by the solid content of centrifugally dewatered cake, in high-solids sequencing batch digesters with and without thermal hydrolysis pretreatment (THP). The results show that the dewaterability of the sludge after digestion was improved by 3.5% (±0.5%) for unpretreated sludge and 5.1% (±0.4%) for thermally hydrolyzed sludge. Compared to the unpretreated sludge digestate, thermal hydrolysis pretreatment eventually resulted in an improvement of dewaterability by 4.6% (±0.5%). Smaller particle size and larger surface area of sludge were induced by thermal hydrolysis and anaerobic digestion treatments. The structure strength and compactness of sludge, represented by elastic modulus and fractal dimension respectively, decreased with increase of digestion time. The porous network structure was broken up by thermal hydrolysis pretreatment and was further weakened during anaerobic digestion, which correspondingly improved the dewaterability of digestates. The logarithm of elastic modulus increased linearly with fractal dimension regardless of the pretreatment. Both fractal dimension and elastic modulus showed linear relationship with dewaterability. The rheological characterization combined with the analysis of fractal dimension of sewage sludge porous network structure was found applicable in quantitative evaluation of sludge dewaterability, which depended positively on both thermal hydrolysis and anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. 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 ...

  5. 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 ...

  6. 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

  7. 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

  8. 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.

  9. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

  11. Enhanced biohydrogen production from oat straw co-digested with cow dung / sewage sludge by combined aerobic digestion and anaerobic fermentation

    Directory of Open Access Journals (Sweden)

    Loretta Li

    2016-03-01

    Full Text Available Hydrogen was produced from oat straw by combined aerobic and anaerobic fermentation with fungi and cow dung. With aerobic pre-digestion, the maximum hydrogen production rate reached 133 ml/g volatile suspended solids per hour. The maximum hydrogen yield was 71.5 ml/g straw in 6 days by biological process. The lignocellulosic conversion of oak-straw waste was 39%, with the complex component converting 68% of the hemi-cellulose and 61% of the cellulose, but only 34% of lignin conversion. Aerobic pre-digestion by Trichoderma viride and Saccharomyces cerevisiae was significantly effective for lignin degradation.  Combining aerobic and anaerobic fermentation is a promising low-cost efficient and environmentally friendly method, compared with hydrogen fermentation, not only for hydrogen production, but also for converting straw biomass.

  12. Evaluation of different types of anaerobic seed sludge for the high rate anaerobic digestion of pig slurry in UASB reactors.

    Science.gov (United States)

    Rico, Carlos; Montes, Jesús A; Rico, José Luis

    2017-08-01

    Three different types of anaerobic sludge (granular, thickened digestate and anaerobic sewage) were evaluated as seed inoculum sources for the high rate anaerobic digestion of pig slurry in UASB reactors. Granular sludge performance was optimal, allowing a high efficiency process yielding a volumetric methane production rate of 4.1LCH 4 L -1 d -1 at 1.5days HRT (0.248LCH 4 g -1 COD) at an organic loading rate of 16.4gCODL -1 d -1 . The thickened digestate sludge experimented flotation problems, thus resulting inappropriate for the UASB process. The anaerobic sewage sludge reactor experimented biomass wash-out, but allowed high process efficiency operation at 3days HRT, yielding a volumetric methane production rate of 1.7LCH 4 L -1 d -1 (0.236LCH 4 g -1 COD) at an organic loading rate of 7.2gCODL -1 d -1 . To guarantee the success of the UASB process, the settleable solids of the slurry must be previously removed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlândia-MG, Brazil

    International Nuclear Information System (INIS)

    Oliveira Silva, Jader de; Filho, Guimes Rodrigues; Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Júlia Graciele; Vieira da Silva, Cleuzilene; Alves Cerqueira, Daniel

    2012-01-01

    Highlights: ► In this study, the sludge was characterized by thermal analyses and FTIR. ► The superior calorific value of the sludge was 16.2 MJ kg −1 . ► The sludge showed a significant biodegradable portion of 65%. ► The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlândia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg −1 was found, which is within the range of values reported in the literature.

  14. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlandia-MG, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Silva, Jader de [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Departamento Municipal de Agua e Esgoto de Uberlandia (DMAE) (Brazil); Filho, Guimes Rodrigues, E-mail: guimes@ufu.br [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Julia Graciele [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Vieira da Silva, Cleuzilene [Faculdade de Engenharia Quimica da Universidade Federal de Uberlandia (Brazil); Alves Cerqueira, Daniel [Instituto de Ciencias Ambientais e Desenvolvimento Sustentavel da Universidade Federal da Bahia (Brazil)

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer In this study, the sludge was characterized by thermal analyses and FTIR. Black-Right-Pointing-Pointer The superior calorific value of the sludge was 16.2 MJ kg{sup -1}. Black-Right-Pointing-Pointer The sludge showed a significant biodegradable portion of 65%. Black-Right-Pointing-Pointer The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlandia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg{sup -1} was found, which is within the range of values reported in the literature.

  15. Sewage sludge utilisation and disposal alternatives and their comparison; Puhdistamolietteiden hyoedyntaemis- ja loppusijoitusvaihtoehdot sekae niiden vertailu

    Energy Technology Data Exchange (ETDEWEB)

    Paatero, P.

    2001-07-01

    Sludge production will presumably not decrease in future. At present agricultural use of sludge is unstable and landfilling will most probably be restricted in the following years. The objective of this thesis is to gather information on options for sludge treatment and utilisation and to compare these options in order to find the best possible solution for future alternatives of sludge utilisation. Finnish and international literature as well as Finnish and EU legislation have been reviewed. Furthermore the mentoring group of this thesis as well as other experts in Finland have been used as a source of information. Sludge contains not only plant nutrients and organic matter but also varying quantities of a number of more or less hazardous substances. The quality and quantity of sewage sludge are described and possible health and environmental risks caused by sewage sludge are pointed out. The legislation linked to sludge utilisation and its demands are also presented. The sludge processing methods reviewed are: thickening, lime stabilisation, aerobic digestion, anaerobic digestion, composting and mechanical and thermal drying. In addition, the positive and negative sides of the stabilisation processes are looked at in greater detail. Agricultural use, landscaping, forestry, landfill, incineration, sludge derived products and newer processing technologies are reviewed as sludge utilisation options. Their environmental impacts, positive and negative sides and practical feasibility are evaluated. Various treatment utilisation combinations are also compared. Furthermore a rough cost assessment is presented. The optimal utilisation alternative has to be chosen case by case. The best use of plant nutrients and valuable organic matter is obtained in agricultural use or in landscaping. In the present situation it is difficult to enhance the portion of agricultural use, and landscaping is restricted by a low demand on the market. Incineration is an expensive option and can

  16. 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)

  17. Optimization of up-flow anaerobic sludge blanket reactor for ...

    African Journals Online (AJOL)

    aghomotsegin

    2013-06-05

    Jun 5, 2013 ... sludge instead of imported commercial anaerobic granulated sludge. Over the ... biogas, granulated anaerobic sludge, industrial wastewater. ... production of methane by methanogenic bacteria. Compared with other treatment processes, USAB ... effluent collector; 8, gas outlet; 9, gas collector; 10, side-arm ...

  18. 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.

  19. Anaerobic biodegradability and treatment of Egyption domestic sewage

    NARCIS (Netherlands)

    Elmitwally, T.A.; Al-Sarawey, A.; El-Sherbiny, M.F.; Zeeman, G.; Lettinga, G.

    2003-01-01

    The anaerobic biodegradability of domestic sewage for four Egyptian villages and four Egyptian cities was determined in batch experiments. The results showed that the biodegradability of the Egyptian-villages sewage (73%) was higher than that of the cities (66%). The higher biodegradability of the

  20. 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.

  1. 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)

  2. Anaerobic co-digestion of municipal food waste and sewage sludge: A comparative life cycle assessment in the context of a waste service provision.

    Science.gov (United States)

    Edwards, Joel; Othman, Maazuza; Crossin, Enda; Burn, Stewart

    2017-01-01

    This study used life cycle assessment to evaluate the environmental impact of anaerobic co-digestion (AcoD) and compared it against the current waste management system in two case study areas. Results indicated AcoD to have less environmental impact for all categories modelled excluding human toxicity, despite the need to collect and pre-treat food waste separately. Uncertainty modelling confirmed that AcoD has a 100% likelihood of a smaller global warming potential, and for acidification, eutrophication and fossil fuel depletion AcoD carried a greater than 85% confidence of inducing a lesser impact than the current waste service. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  3. 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)

  4. 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

  5. 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)

  6. 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...

  7. The influence of aerobic sludge retention time on anaerobic co ...

    African Journals Online (AJOL)

    ABR) and aerobic plug flow reactor (PFR) were operated aiming to minimize excess sludge output of the activated sludge process through coupled alkaline hydrolysis and anaerobic digestion. Variations in the effluent total chemical oxygen ...

  8. 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)

  9. 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 ...

  10. 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...

  11. 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

  12. 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...

  13. 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.

  14. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-07-01

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

  16. Enhanced methane yield by co-digestion of sewage sludge with micro-algae and catering waste leachate.

    Science.gov (United States)

    2018-04-04

    The co-digestion of different wastes is a promising concept to improve methane generation during anaerobic process. However, the anaerobic co-digestion of catering waste leachate with algal biomass and sewage sludge has not been studied to date. This work investigated the methane generation by the anaerobic co-digestion of different mixtures of catering waste leachate, micro-algal biomass, and sewage sludge. Co-digestion of waste mixture containing equal ratios of three substrates had 39.31% higher methane yield than anaerobic digestion of raw sludge. This was possibly due to a proliferation of methanogens during the co-digestion period induced by multi-phase digestion of different wastes with different degrees of digestibility. Therefore, co-digestion of catering waste leachate, micro-algal biomass, and sewage sludge appears to be an efficient technology for energy conversion from waste resources. The scientific application of this co-digestion technology with these three substrates may play a role in solving important environmental issues of waste management.

  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. 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...

  19. 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....

  20. 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.

  1. 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.

  2. Siloxane removal and sludge disintegration using thermo-alkaline treatments with air stripping prior to anaerobic sludge digestion

    International Nuclear Information System (INIS)

    Oshita, Kazuyuki; Fujime, Motochika; Takaoka, Masaki; Fujimori, Takashi; Appels, Lise; Dewil, Raf

    2015-01-01

    Highlights: • Siloxanes hamper the energy-use of anaerobic digestion biogas. • D5 siloxane was considered as target compound in this study. • The treatment removed 80% of D5 in sewage sludge at 55 °C and 135 g-NaOH kg −1 -VTS. • D5 removal and the disintegration of VSS in the sludge were correlated. • At the optimal conditions, the costs of anaerobic digestion were notably diminished. - Abstract: A thermo-alkaline treatment with air stripping was applied before anaerobic sludge digestion for both siloxane removal and sludge disintegration. The treatment was expected to increase the amount of biogas produced and to reduce the amount of siloxane in the gas. Adding sodium hydroxide (NaOH) to the sludge improved the removal of siloxane from the sludge, with approximately 90% of the siloxane removed to the gas phase using a thermo-alkaline treatment. Over 80% of decamethylcyclopentasiloxane (D5) could be removed under the following conditions: 55 °C treatment temperature, 135 g-NaOH kg −1 volatile total solids (VTS), and 0.5 L min −1 air-stripping rate. The disintegration ratio of volatile suspended solids (VSS) in the sludge was correlated with the D5 removal ratio. Because most of the siloxane was adsorbed to, or was contained in the VSS, the siloxane removal ratio increased with VSS disintegration. Finally, the energy consumption and operational costs of this system were evaluated for several scenarios. Thermo-alkaline treatment at the indicated operational conditions had the lowest operating costs for a 400 m 3 day −1 anaerobic sludge digestion system

  3. Life cycle assessment of biogas from sewage treatment sludge; Livscykelanalys av biogas fraan avloppsreningsverksslam

    Energy Technology Data Exchange (ETDEWEB)

    Palm, David; Ek, Mats (IVL Swedish Environmental Research Inst., Stockholm (Sweden))

    2010-08-15

    This report analyses the environmental impact from 1MJ of biogas (as vehicle fuel) produced by anaerobic digestion of sewage sludge. Data are primarily taken from Kaeppala sewage treatment plant, but have been complemented with data from literature. As a base case, the biogas has only been given the environmental burden from upgrading and purification of raw gas. This is because the anaerobic digestion is an inherent part of the waste water treatment in Sweden, biogas being produced regardless of its chosen end utilization. Calculations have also been performed with system expansion where the anaerobic digestion, sludge treatment and replaced mineral fertilizer have been included in the analysis, as well as calculations based on economic and energy allocation. The results have been characterised in accordance to CML (2007) for the potential of global warming on a 100 year perspective, eutrophication, acidification, photochemical oxidation creation and particles. The study represents a Swedish state-of-the-art plant for biogas production but also includes a sensitivity analysis that cover a Swedish average plant and a worst case plant. The sensitivity analysis shows a major impact on the results from methane leakage during anaerobic digestion and upgrading. The electricity consumption and choice of Swedish average electricity versus Swedish marginal electricity is of less importance for the outcome of the study

  4. Transformation products and human metabolites of triclocarban and tricllosan in sewage sludge across the United States

    Science.gov (United States)

    Pycke, Benny F.G.; Roll, Isaac B.; Brownawell, Bruce J.; Kinney, Chad A.; Furlong, Edward T.; Kolpin, Dana W.; Halden, Rolf U.

    2014-01-01

    Removal of triclocarban (TCC) and triclosan (TCS) from wastewater is a function of adsorption, abiotic degradation, and microbial mineralization or transformation, reactions that are not currently controlled or optimized in the pollution control infrastructure of standard wastewater treatment. Here, we report on the levels of eight transformation products, human metabolites, and manufacturing byproducts of TCC and TCS in raw and treated sewage sludge. Two sample sets were studied: samples collected once from 14 wastewater treatment plants (WWTPs) representing nine states, and multiple samples collected from one WWTP monitored for 12 months. Time-course analysis of significant mass fluxes (α = 0.01) indicate that transformation of TCC (dechlorination) and TCS (methylation) occurred during sewage conveyance and treatment. Strong linear correlations were found between TCC and the human metabolite 2′-hydroxy-TCC (r = 0.84), and between the TCC-dechlorination products dichlorocarbanilide (DCC) and monochlorocarbanilide (r = 0.99). Mass ratios of DCC-to-TCC and of methyl-triclosan (MeTCS)-to-TCS, serving as indicators of transformation activity, revealed that transformation was widespread under different treatment regimes across the WWTPs sampled, though the degree of transformation varied significantly among study sites (α = 0.01). The analysis of sludge sampled before and after different unit operation steps (i.e., anaerobic digestion, sludge heat treatment, and sludge drying) yielded insights into the extent and location of TCC and TCS transformation. Results showed anaerobic digestion to be important for MeTCS transformation (37–74%), whereas its contribution to partial TCC dechlorination was limited (0.4–2.1%). This longitudinal and nationwide survey is the first to report the occurrence of transformation products, human metabolites, and manufacturing byproducts of TCC and TCS in sewage sludge.

  5. Evaluation of sludge properties in a pilot-scale UASB reactor for sewage treatment in a temperate region.

    Science.gov (United States)

    Syutsubo, K; Yoochatchaval, W; Tsushima, I; Araki, N; Kubota, K; Onodera, T; Takahashi, M; Yamaguchi, T; Yoneyama, Y

    2011-01-01

    In this study, continuous operation of a pilot-scale upflow anaerobic sludge blanket (UASB) reactor for sewage treatment was conducted for 630 days to investigate the physical and microbial characteristics of the retained sludge. The UASB reactor with a working volume of 20.2 m(3) was operated at ambient temperature (16-29 °C) and seeded with digested sludge. After 180 days of operation, when the sewage temperature had dropped to 20 °C or lower, the removal efficiency of both total suspended solids (TSS) and total biochemical oxygen demand (BOD) deteriorated due to washout of retained sludge. At low temperature, the cellulose concentration of the UASB sludge increased owing to the rate limitation of the hydrolytic reaction of suspended solids in the sewage. However, after an improvement in sludge retention (settleability and concentration) in the UASB reactor, the process performance stabilized and gave sufficient results (68% of TSS removal, 75% of total BOD removal) at an hydraulic retention time (HRT) of 9.7 h. The methanogenic activity of the retained sludge significantly increased after day 246 due to the accumulation of Methanosaeta and Methanobacterium following the improvement in sludge retention in the UASB reactor. Acid-forming bacteria from phylum Bacteroidetes were detected at high frequency; thus, these bacteria may have an important role in suspended solids degradation.

  6. 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)

  7. Mass and energy balance: application to the sanitary sewage treatment with an upflow anaerobic sludge blanket (UASB) reactors to temperature of 20 deg C; Balanco de massa e energia: aplicacao ao tratamento de esgotos sanitarios com reatores anaerobicos de manta de lodo (UASB) a temperatura de 20 deg C

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, Katherine Ivonne Alcocer

    1992-07-01

    A feasibility study of an Upflow Anaerobic Sludge Blanket (UASB) reactor use as a sewage treatment plant component for areas with average temperature bellow 20 deg C was performed. The literature on UASB reactor indicates that a 70 % chemical oxygen demand (COD) removal al 20 and 6 to 17 hr hydraulic detention time is possible in sewage treatment plants. This study was developed for a Oruro (Bolivia) district and the plant was designed for a population of up to 10,000 inhabitants. This city presents average temperatures lower than 20 deg C being necessary to heat the sewage if is used the UASB reactor. Based on the performance simulation of mass and energy balances it was found that 84 % COD removal and 92 % total suspended solids removal are possible. The potential average energy production (61 kW due to methane combustion) is less than 10 % of the power consumption for heating, which indicates that the use of the methane may be expensive. The evaluated energy rate to be applied to the sewage for heating is 0.33 kW/m{sup 3} d{sup -1} which is significantly greater than the necessary energy to introduce oxygen in aerobic treatment systems. However total energy demand for aerobic systems must be evaluated for each particular case. (author)

  8. Impact of fertilizing with raw or anaerobically digested sewage sludge on the abundance of antibiotic-resistant coliforms, antibiotic resistance genes, and pathogenic bacteria in soil and on vegetables at harvest.

    Science.gov (United States)

    Rahube, Teddie O; Marti, Romain; Scott, Andrew; Tien, Yuan-Ching; Murray, Roger; Sabourin, Lyne; Zhang, Yun; Duenk, Peter; Lapen, David R; Topp, Edward

    2014-11-01

    The consumption of crops fertilized with human waste represents a potential route of exposure to antibiotic-resistant fecal bacteria. The present study evaluated the abundance of bacteria and antibiotic resistance genes by using both culture-dependent and molecular methods. Various vegetables (lettuce, carrots, radish, and tomatoes) were sown into field plots fertilized inorganically or with class B biosolids or untreated municipal sewage sludge and harvested when of marketable quality. Analysis of viable pathogenic bacteria or antibiotic-resistant coliform bacteria by plate counts did not reveal significant treatment effects of fertilization with class B biosolids or untreated sewage sludge on the vegetables. Numerous targeted genes associated with antibiotic resistance and mobile genetic elements were detected by PCR in soil and on vegetables at harvest from plots that received no organic amendment. However, in the season of application, vegetables harvested from plots treated with either material carried gene targets not detected in the absence of amendment. Several gene targets evaluated by using quantitative PCR (qPCR) were considerably more abundant on vegetables harvested from sewage sludge-treated plots than on vegetables from control plots in the season of application, whereas vegetables harvested the following year revealed no treatment effect. Overall, the results of the present study suggest that producing vegetable crops in ground fertilized with human waste without appropriate delay or pretreatment will result in an additional burden of antibiotic resistance genes on harvested crops. Managing human exposure to antibiotic resistance genes carried in human waste must be undertaken through judicious agricultural practice. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  9. 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

  10. [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.

  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. 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.

  18. 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...

  19. 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…

  20. New trends in processing and disposal of municipal and industrial sewage sludges. 8. Joint seminar `waste water technology` with exhibitor`s forum; Neue Trends bei der Behandlung und Entsorgung kommunaler und industrieller Klaerschlaemme. Achtes gemeinsames Seminar `Abwassertechnik` mit Ausstellerforum

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The present conference proceedings handle all aspects of sewage sludge disposal: agricultural use of sewage sludge, processing in anaerobic reactors, composting, drain, drying, gasification, combustion, economical aspects, ecological aspects, building, design and operation of modern sludge treatment plants. (SR) [Deutsch] Der vorliegende Tagungsband behandelt alle Aspekte der Klaerschlammentsorgung: landwirtschaftliche Nutzung von Klaerschlamm, Behandlung in Anaerobreaktoren, Kompostierung, Entwaesserung, Trocknung, Vergasung, Verbrennung, wirtschaftliche Aspekte, oekologische Aspekte, Bau, Ausruestung und Betrieb von modernen Schlammbehandlungsanlagen. (SR)

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

    African Journals Online (AJOL)

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

  2. The effect of sludge recirculation rate on a UASB-digester treating domestic sewage at 15 °C.

    Science.gov (United States)

    Zhang, Lei; Hendrickx, Tim L G; Kampman, Christel; Zeeman, Grietje; Temmink, Hardy; Li, Weiguang; Buisman, Cees J N

    2012-01-01

    The anaerobic treatment of low strength domestic sewage at low temperature is an attractive and important topic at present. The upflow anaerobic sludge bed (UASB)-digester system is one of the anaerobic systems to challenge low temperature and concentrations. The effect of sludge recirculation rate on a UASB-digester system treating domestic sewage at 15 °C was studied in this research. A sludge recirculation rate of 0.9, 2.6 and 12.5% of the influent flow rate was investigated. The results showed that the total chemical oxygen demand (COD) removal efficiency rose with increasing sludge recirculation rate. A sludge recirculation rate of 0.9% of the influent flow rate led to organic solids accumulation in the UASB reactor. After the sludge recirculation rate increased from 0.9 to 2.6%, the stability of the UASB sludge was substantially improved from 0.37 to 0.15 g CH₄-COD/g COD, and the bio-gas production in the digester went up from 2.9 to 7.4 L/d. The stability of the UASB sludge and bio-gas production in the digester were not significantly further improved by increasing sludge recirculation rate to 12.5% of the influent flow rate, but the biogas production in the UASB increased from 0.37 to 1.2 L/d. It is recommended to apply a maximum sludge recirculation rate of 2-2.5% of the influent flow rate in a UASB-digester system, as this still allows energy self-sufficiency of the system.

  3. Irradiated sewage sludge for application to cropland. Results of a co-ordinated research project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-10-01

    Modern urban societies produce large volumes of sewage, which are transported through a network of underground sewers to wastewater treatment plants, where one or more stages of physical, biological and chemical treatment are imposed. Considerable tonnages of aerobically, and sometimes anaerobically, digested sludge are produced, and treated or untreated effluent is discharged to lagoons, waterways or the ocean. The disposal of sewage sludge is a major issue for municipal authorities. There are increasing legislative restrictions in many countries on disposal methods (e.g. incineration, landfill, composting) including surface application to agricultural land. Sludge can either be viewed as a dangerous waste requiring expensive disposal procedures, or it can be seen as a resource for possible use in agriculture as a soil conditioning agent and a source of plant nutrients. Untreated sewage sludge presents a public-health hazard as it contains human pathogens, including bacteria, viruses and other harmful organisms. Although it has been demonstrated that an appropriate dose of gamma-irradiation can eliminate human parasites and bacterial pathogens from sewage sludge, there is still public concern about the presence of viruses, as well as heavy metals and toxic organic compounds from industrial sources that could enter the food chain if sludge is applied to croplands. More information is also needed on the value of sludge as a source of plant nutrients, expressed in terms of fertilizer equivalence. In this regard, isotopic labelling techniques have a unique role to play in estimating the contribution of sewage sludge to crop nutrition. As a result of recommendations formulated at a Consultants Meeting organized by the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture and the IAEA Division of Physical and Chemical Sciences, 5-9 December 1994 (IAEA-TECDOC-971, Sewage Sludge and Wastewater for Use in Agriculture) the Joint Division implemented a Co

  4. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    Shireen Meher Kotay; Debabrata Das [Fermentation Technology Lab., Department of Biotechnology, Indian Institute of Technology Kharagpur, W.B., INDIA-721302 (India)

    2006-07-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H{sub 2} production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H{sub 2}/ g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H{sub 2}/g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5%w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H{sub 2}/ g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H{sub 2} g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H{sub 2}/g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H{sub 2}/g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge

  5. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    Shireen Meher Kotay; Debabrata Das [Fermentation Technology Lab., Department of Biotechnology, Indian Institute of Technology Kharagpur, W.B., INDIA-721302 (India)

    2006-07-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H{sub 2} production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H{sub 2}/ g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H{sub 2}/ g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5% w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H{sub 2}/ g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H{sub 2}/ g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H{sub 2} / g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H{sub 2}/ g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from

  6. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    International Nuclear Information System (INIS)

    Shireen Meher Kotay; Debabrata Das

    2006-01-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H 2 production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H 2 / g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H 2 /g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5%w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H 2 / g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H 2 g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H 2 /g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H 2 /g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge. (authors)

  7. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    International Nuclear Information System (INIS)

    Shireen Meher Kotay; Debabrata Das

    2006-01-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H 2 production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H 2 / g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H 2 / g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5% w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H 2 / g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H 2 / g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H 2 / g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H 2 / g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge. (authors)

  8. STUDY ON MAXIMUM SPECIFIC SLUDGE ACIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The maximum specific sludge activity of granular sludge from large-scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (diffusion, substrate sort, substrate concentration and granular size) were studied. The general principle and procedure for the precise measurement of maximum specific sludge activity were suggested. The potential capacity of loading rate of the IC and Biobed anaerobic reactors were analyzed and compared by use of the batch tests results.

  9. 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)

  10. Enhancement of anaerobic sludge digestion by high-pressure homogenization.

    Science.gov (United States)

    Zhang, Sheng; Zhang, Panyue; Zhang, Guangming; Fan, Jie; Zhang, Yuxuan

    2012-08-01

    To improve anaerobic sludge digestion efficiency, the effects of high-pressure homogenization (HPH) conditions on the anaerobic sludge digestion were investigated. The VS and TCOD were significantly removed with the anaerobic digestion, and the VS removal and TCOD removal increased with increasing the homogenization pressure and homogenization cycle number; correspondingly, the accumulative biogas production also increased with increasing the homogenization pressure and homogenization cycle number. The optimal homogenization pressure was 50 MPa for one homogenization cycle and 40 MPa for two homogenization cycles. The SCOD of the sludge supernatant significantly increased with increasing the homogenization pressure and homogenization cycle number due to the sludge disintegration. The relationship between the biogas production and the sludge disintegration showed that the accumulative biogas and methane production were mainly enhanced by the sludge disintegration, which accelerated the anaerobic digestion process and improved the methane content in the biogas. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. 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

  12. 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

  13. 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

  14. Estimates of nitrogen availability of poultry manure and sewage sludge amendments in mined prime farmlands

    International Nuclear Information System (INIS)

    Zhai, Q.; Barnhisel, R.I.

    1994-01-01

    The application of poultry manure and sewage sludge may speed up the return of productivity of prime farmland following surface mining, as well as for utilizing nutrients in these wastes. However, excessive application may result in nitrate contamination of ground water. This research was carried out under laboratory and field conditions to test this concern. The objective was to examine nitrogen mineralization indices used to evaluate nitrogen availability to wheat (Triticum astivum). Two field experiments were established in fall 1992 in western Kentucky. Sewage sludge was applied to both topsoil and subsoil at one site, and poultry manure was applied to only the topsoil at the second site. Three rates of organic amendments were used in these experiments. Soil available nitrogen was evaluated by both biological mineralization and chemical extraction methods. A 7-day anaerobic incubation method was well correlated with grain yield and was superior to other chemical methods in predicting nitrogen availability. Both sewage sludge and poultry manure application to the topsoil provided a high available nitrogen source for wheat growth, which resulted in a higher yield than that for the unamended control

  15. CO-DIGESTION OF SEWAGE SLUDGE AND MATURE LANDFILL LEACHATE IN PRE-BIOAUGMENTED SYSTEM

    Directory of Open Access Journals (Sweden)

    Agnieszka Montusiewicz

    2014-10-01

    Full Text Available The study examined the effects of co-digestion of sewage sludge and mature landfill leachate at the volumetric ratio of 95:5% in primarily bioaugmented system. Bioaugmentation was carried out with the use of commercial product Arkea® in the volumetric dose of 5% and lasted three months prior to the co-digestion start-up. Co-digestion was undergone without bioaugmentation. The results indicated that in the first period (of three months following bioaugmentation, co-digestion led to biogas/methane yields only 5-8% lower as compared to anaerobic digestion of sewage sludge, and the differences were not statistically significant. Moreover, a comparable value of volatile solids removal was obtained. However, the effects became worse over time, i.e. a lower organics removal efficiency of 16% as well as 9.5–13% decreases of biogas/methane yields were achieved by applying co-digestion for a further period (of the same duration. Co-digestion of sewage sludge and mature landfill leachate could be recognized as quite efficient in the system that was primarily bioaugmented with the use of Arkea®. However, the beneficial impact of bioaugmentation remained for the limited period of three months after its completion. To sustain the favourable effects a periodical, repeatable bioaugmentation of the co-digestion system is required.

  16. 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.

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  18. 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.

  19. 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.

  20. 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)

  1. 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)

  2. Microbial hydrogen production from sewage sludge bioaugmented with a constructed microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    Kotay, Shireen Meher; Das, Debabrata [Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302 (India)

    2010-10-15

    A constructed microbial consortium was formulated from three facultative H{sub 2}-producing anaerobic bacteria, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1. This consortium was tested as the seed culture for H{sub 2} production. In the initial studies with defined medium (MYG), E. cloacae produced more H{sub 2} than the other two strains and it also was found to be the dominant member when consortium was used. On the other hand, B. coagulans as a pure culture gave better H{sub 2} yield (37.16 ml H{sub 2}/g COD{sub consumed}) than the other two strains using sewage sludge as substrate. The pretreatment of sludge included sterilization (15% v/v), dilution and supplementation with 0.5% w/v glucose, which was found to be essential to screen out the H{sub 2} consuming bacteria and ameliorate the H{sub 2} production. Considering (1:1:1) defined consortium as inoculum, COD reduction was higher and yield of H{sub 2} was recorded to be 41.23 ml H{sub 2}/g COD{sub reduced}. Microbial profiling of the spent sludge showed that B. coagulans was the dominant member in the constructed consortium contributing towards H{sub 2} production. Increase in H{sub 2} yield indicated that in consortium, the substrate utilization was significantly higher. The H{sub 2} yield from pretreated sludge (35.54 ml H{sub 2}/g sludge) was comparatively higher than that reported in literature (8.1-16.9 ml H{sub 2}/g sludge). Employing formulated microbial consortium for biohydrogen production is a successful attempt to augment the H{sub 2} yield from sewage sludge. (author)

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

    International Nuclear Information System (INIS)

    Schmitt, Theo G.; Gretzschel, Oliver

    2014-03-01

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

  4. Enrichment of denitrifying methanotrophic bacteria for application after direct low-temperature anaerobic sewage treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kampman, Christel, E-mail: christel.kampman@wur.nl [Sub-department of Environmental Technology, Wageningen University, P.O. Box 17, 6700 AA, Wageningen (Netherlands); Hendrickx, Tim L.G. [Sub-department of Environmental Technology, Wageningen University, P.O. Box 17, 6700 AA, Wageningen (Netherlands); Luesken, Francisca A.; Alen, Theo A. van; Op den Camp, Huub J.M.; Jetten, Mike S.M. [Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Zeeman, Grietje; Buisman, Cees J.N.; Temmink, Hardy [Sub-department of Environmental Technology, Wageningen University, P.O. Box 17, 6700 AA, Wageningen (Netherlands)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer A new concept for low-temperature anaerobic sewage treatment is proposed. Black-Right-Pointing-Pointer In this concept, denitrification and methane oxidation are performed by Methylomirabilis oxyfera. Black-Right-Pointing-Pointer The bacteria were enriched from fresh water sediment using sequencing fed-batch reactors. Black-Right-Pointing-Pointer The volumetric consumption rate has to be increased by an order of magnitude for practical application. Black-Right-Pointing-Pointer Further research should focus on systems with improved biomass retention. - Abstract: Despite many advantages of anaerobic sewage treatment over conventional activated sludge treatment, it has not yet been applied in temperate zones. This is especially because effluent from low-temperature anaerobic treatment contains nitrogen and dissolved methane. The presence of nitrogen and methane offers the opportunity to develop a reactor in which methane is used as electron donor for denitrification. Such a reactor could be used in a new concept for low-temperature anaerobic sewage treatment, consisting of a UASB-digester system, a reactor for denitrification coupled to anaerobic methane oxidation, and a nitritation reactor. In the present study denitrifying methanotrophic bacteria similar to 'Candidatus Methylomirabilis oxyfera' were enriched. Maximum volumetric nitrite consumption rates were 33.5 mg NO{sub 2}{sup -}-N/L d (using synthetic medium) and 37.8 mg NO{sub 2}{sup -}-N/L d (using medium containing effluent from a sewage treatment plant), which are similar to the maximum rate reported so far. Though the goal was to increase the rates, in both reactors, after reaching these maximum rates, volumetric nitrite consumption rates decreased in time. Results indicate biomass washout may have significantly decelerated enrichment. Therefore, to obtain higher volumetric consumption rates, further research should focus on systems with complete biomass

  5. Enrichment of denitrifying methanotrophic bacteria for application after direct low-temperature anaerobic sewage treatment

    International Nuclear Information System (INIS)

    Kampman, Christel; Hendrickx, Tim L.G.; Luesken, Francisca A.; Alen, Theo A. van; Op den Camp, Huub J.M.; Jetten, Mike S.M.; Zeeman, Grietje; Buisman, Cees J.N.; Temmink, Hardy

    2012-01-01

    Highlights: ► A new concept for low-temperature anaerobic sewage treatment is proposed. ► In this concept, denitrification and methane oxidation are performed by Methylomirabilis oxyfera. ► The bacteria were enriched from fresh water sediment using sequencing fed-batch reactors. ► The volumetric consumption rate has to be increased by an order of magnitude for practical application. ► Further research should focus on systems with improved biomass retention. - Abstract: Despite many advantages of anaerobic sewage treatment over conventional activated sludge treatment, it has not yet been applied in temperate zones. This is especially because effluent from low-temperature anaerobic treatment contains nitrogen and dissolved methane. The presence of nitrogen and methane offers the opportunity to develop a reactor in which methane is used as electron donor for denitrification. Such a reactor could be used in a new concept for low-temperature anaerobic sewage treatment, consisting of a UASB-digester system, a reactor for denitrification coupled to anaerobic methane oxidation, and a nitritation reactor. In the present study denitrifying methanotrophic bacteria similar to ‘Candidatus Methylomirabilis oxyfera’ were enriched. Maximum volumetric nitrite consumption rates were 33.5 mg NO 2 − -N/L d (using synthetic medium) and 37.8 mg NO 2 − -N/L d (using medium containing effluent from a sewage treatment plant), which are similar to the maximum rate reported so far. Though the goal was to increase the rates, in both reactors, after reaching these maximum rates, volumetric nitrite consumption rates decreased in time. Results indicate biomass washout may have significantly decelerated enrichment. Therefore, to obtain higher volumetric consumption rates, further research should focus on systems with complete biomass retention.

  6. Speciation evolution of zinc and copper during pyrolysis and hydrothermal carbonization treatments of sewage sludges.

    Science.gov (United States)

    Huang, Rixiang; Zhang, Bei; Saad, Emily M; Ingall, Ellery D; Tang, Yuanzhi

    2018-04-01

    Thermal and hydrothermal treatments are promising techniques for sewage sludge management that can potentially facilitate safe waste disposal, energy recovery, and nutrient recovery/recycling. Content and speciation of heavy metals in the treatment products affect the potential environmental risks upon sludge disposal and/or application of the treatment products. Therefore, it is important to study the speciation transformation of heavy metals and the effects of treatment conditions. By combining synchrotron X-ray spectroscopy/microscopy analysis and sequential chemical extraction, this study systematically characterized the speciation of Zn and Cu in municipal sewage sludges and their chars derived from pyrolysis (a representative thermal treatment technique) and hydrothermal carbonization (HTC; a representative hydrothermal treatment technique). Spectroscopy analysis revealed enhanced sulfidation of Zn and Cu by anaerobic digestion and HTC treatments, as compared to desulfidation by pyrolysis. Overall, changes in the chemical speciation and matrix properties led to reduced mobility of Zn and Cu in the treatment products. These results provide insights into the reaction mechanisms during pyrolysis and HTC treatments of sludges and can help evaluate the environmental/health risks associated with the metals in the treatment products. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Speciation evolution of zinc and copper during pyrolysis and hydrothermal carbonization treatments of sewage sludges

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Rixiang; Zhang, Bei; Saad, Emily M.; Ingall, Ellery D.; Tang, Yuanzhi

    2018-04-01

    Thermal and hydrothermal treatments are promising techniques for sewage sludge management that can potentially facilitate safe waste disposal, energy recovery, and nutrient recovery/recycling. Content and speciation of heavy metals in the treatment products affect the potential environmental risks upon sludge disposal and/or application of the treatment products. Therefore, it is important to study the speciation transformation of heavy metals and the effects of treatment conditions. By combining synchrotron X-ray spectroscopy/microscopy analysis and sequential chemical extraction, this study systematically characterized the speciation of Zn and Cu in municipal sewage sludges and their chars derived from pyrolysis (a representative thermal treatment technique) and hydrothermal carbonization (HTC; a representative hydrothermal treatment technique). Spectroscopy analysis revealed enhanced sulfidation of Zn and Cu by anaerobic digestion and HTC treatments, as compared to desulfidation by pyrolysis. Overall, changes in the chemical speciation and matrix properties led to reduced mobility of Zn and Cu in the treatment products. These results provide insights into the reaction mechanisms during pyrolysis and HTC treatments of sludges and can help evaluate the environmental/health risks associated with the metals in the treatment products.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Enhancement of ultrasonic disintegration of sewage sludge by aeration.

    Science.gov (United States)

    Zhao, He; Zhang, Panyue; Zhang, Guangming; Cheng, Rong

    2016-04-01

    Sonication is an effective way for sludge disintegration, which can significantly improve the efficiency of anaerobic digestion to reduce and recycle use of sludge. But high energy consumption limits the wide application of sonication. In order to improve ultrasonic sludge disintegration efficiency and reduce energy consumption, aeration was introduced. Results showed that sludge disintegration efficiency was improved significantly by combining aeration with ultrasound. The aeration flow rate, gas bubble size, ultrasonic density and aeration timing had impacts on sludge disintegration efficiency. Aeration that used in later stage of ultrasonic irradiation with low aeration flow rate, small gas bubbles significantly improved ultrasonic disintegration sludge efficiency. At the optimal conditions of 0.4 W/mL ultrasonic irradiation density, 30 mL/min of aeration flow rate, 5 min of aeration in later stage and small gas bubbles, ultrasonic sludge disintegration efficiency was increased by 45% and one third of ultrasonic energy was saved. This approach will greatly benefit the application of ultrasonic sludge disintegration and strongly promote the treatment and recycle of wastewater sludge. Copyright © 2015. Published by Elsevier B.V.

  14. 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)

  15. 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

  16. 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...

  17. Sewage sludge stabilisation and fertiliser value in a silvopastoral system developed with Eucalyptus nitens Maiden in Lugo (Spain).

    Science.gov (United States)

    Mosquera-Losada, M R; Ferreiro-Domínguez, N; Daboussi, S; Rigueiro-Rodríguez, A

    2016-10-01

    Copper (Cu) is one of the heavy metals with highest proportion in sewage sludge. In Europe, sewage sludge should be stabilised before using it as a fertiliser in agriculture. Depending on the stabilisation process, sewage sludge has different Cu contents, and soil Cu incorporation rates. This study was undertaken to examine the effect of fertilisation with different types of sewage sludge (anaerobic, composted, and pelletised) on the concentration of total and available Cu in the soil, the tree growth, the pasture production, and the concentration of Cu in the pasture when compared with control treatments (i.e. no fertilisation and mineral fertilisation) in a silvopastoral system under Eucalyptus nitens Maiden. The results of this experiment show that an improvement of the soil pH increased the incorporation and the mineralisation of the sewage sludge and litter, and therefore, the release of Cu from the soil. Moreover, the concentration of Cu in the pasture and the levels of Cu extracted by the pasture improved when the soil organic matter decreased because the high levels of organic matter in the soil could have formed Cu complex. The composted sewage sludge (COM) increased a) the soil variables studied (pH, total Cu, and available Cu) and b) the Cu extracted by the pasture, both probably due to the higher inputs of cations made with it. In any case, the levels of Cu found in the soil never exceeded the maximums as set by Spanish regulations and did not cause harmful effects on the plants and animals. Therefore, the use of COM as an organic fertiliser should be promoted in silvopastoral systems established in edaphoclimatic conditions similar to this study because COM enhanced the productivity of the system from a viewpoint of the soil and the pasture, without causing any environmental damage. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Differences on nitrogen availability in a soil amended with fresh, composted and thermally-dried sewage sludge.

    Science.gov (United States)

    Tarrasón, D; Ojeda, G; Ortiz, O; Alcañiz, J M

    2008-01-01

    Anaerobically-digested sludge called fresh sludge (F), composted sludge (C) and thermally-drying sludge (T), all from the same batch, were applied to the surface of a calcareous Udic Calciustept with loamy texture. Dosage equivalent was 10 t ha(-1) of dry matter. The concentration of mineral nitrogen (ammonium and nitrate) in the soil was measured in order to estimate the effects of the post-treatments to which the different kinds of sewage sludge are subjected in relation to the availability of N in the surface layer of the soil. The most significant differences in NH(4)-N and NO(3)-N concentrations due to the transformation of the organic matter were observed during the first three weeks following soil amendment. Thermally-dried and composted sludge initially displayed higher concentrations of ammonium and nitrate in soil. Five months after the amendment, soil applied with fresh sludge showed the highest concentrations of NH(4)-N and NO(3)-N (6.1 and 36.6 mg kg(-1), respectively). It is clear that the processes of composting and thermal-drying influence the bioavailability of nitrogen from the different types of sewage sludge.

  19. Factors Involved in Sludge Granulation under Anaerobic Conditions

    Directory of Open Access Journals (Sweden)

    Jalal Shayegan

    2011-03-01

    Full Text Available This paper investigates the effects of factors involved in sludge anaerobic granulation. Granulated sludge formation is the main parameter contributing to the success of UASB reactors. Anaerobic granulation leads to reduced reactor size, space requirement, and investment costs. Operation costs are also greatly reduced due to lack of aeration. An important parameter affecting process performance is the size of sludge granules; the factors involved in granule size will be investigated. Some of the important parameters of anaerobic sludge granulation are: existence of growth cores as inert particles or granulated sludge, process operational conditions (Sludge Loading Rate and Organic Loading Rate, Loading rate increase and …, and environment conditions (nutrients, temperature, pH, combination and ….

  20. Applicability and trends of anaerobic granular sludge treatment processes

    International Nuclear Information System (INIS)

    Lim, Seung Joo; Kim, Tak-Hyun

    2014-01-01

    Anaerobic granular sludge treatment processes have been continuously developed, although the anaerobic sludge granulation process was not clearly understood. In this review, an upflow anaerobic sludge blanket (UASB), an expanded granule sludge blanket (EGSB), and a static granular bed reactor (SGBR) were introduced as components of a representative anaerobic granular sludge treatment processes. The characteristics and application trends of each reactor were presented. The UASB reactor was developed in the late 1970s and its use has been rapidly widespread due to the excellent performance. With the active granules, this reactor is able to treat various high-strength wastewaters as well as municipal wastewater. Most soluble industrial wastewaters can be efficiently applied using a UASB. The EGSB reactor was developed owing to give more chance to contact between wastewater and the granules. Dispersed sludge is separated from mature granules using the rapid upward velocity in this reactor. The EGSB reactor shows the excellent performance in treating low-strength and/or high-strength wastewater, especially under low temperatures. The SGBR, developed at Iowa State University, is one of anaerobic granular sludge treatment processes. Although the configuration of the SGBR is very simple, the performance of this system is similar to that of the UASB or EGSB reactor. The anaerobic sludge granulation processes showed excellent performance for various wastewaters at a broad range of organic loading rate in lab-, pilot-scale tests. This leads to erect thousands of full-scale granular processes, which has been widely operated around the world. -- Highlights: • Anaerobic sludge granulation is a key parameter for maintaining granular processes. • Anaerobic granular digestion processes are applicable for various wastewaters. • The UASB is an economic high-rate anaerobic granular process. • The EGSB can treat high-strength wastewater using expanding granules. • The SGBR is

  1. 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....

  2. 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)

  3. 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)

  4. 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.

  5. Thermal pre-treatment of primary and secondary sludge at 70 °C prior to anaerobic digestion

    DEFF Research Database (Denmark)

    Skiadas, Ioannis; Gavala, Hariklia N.; Lu, J.

    2005-01-01

    In general, mesophilic anaerobic digestion of sewage sludge is more widely used compared tothermophilic digestion, mainly because of the lower energy requirements and higher stability of the process. However, the thermophilic anaerobic digestion process is usually characterised by accelerated...... studyinvestigates the effect of the pre-treatment at 70 °C on thermophilic (55 °C) anaerobic digestion of primaryand secondary sludge in continuously operated digesters. Thermal pre-treatment of primary and secondarysludge at 70 °C enhanced the removal of organic matter and the methane production during...... the subsequentanaerobic digestion step at 55 °C. It also greatly contributed to the destruction of pathogens present inprimary sludge. Finally it results in enhanced microbial activities of the subsequent anaerobic stepsuggesting that the same efficiencies in organic matter removal and methane recovery could be obtained...

  6. 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

  7. 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.

  8. Sewage sludge disintegration - a review of current processes; Klaerschlammdesintegration - Ueberblick ueber verschiedene Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Nickel, K. [ULTRAWAVES Wasser- und Umwelttechnologien GmbH, Hamburg (Germany); Neis, U. [Technische Univ. Hamburg-Harburg, Hamburg (Germany). Arbeitsbereich Abwasserwirtschaft

    2003-07-01

    Anaerobic stabilisation is an established technology for reducing sewage sludge volumes, but it has the drawback of low conversion rates. The speed of the process is determined by the hydrolysis of the solid fraction of the sludge. According to the current state of knowledge, exoenzymes produced by the fermenting microorganisms attack the particulate material and dissolve monomers. Production of exoenzymes is an energy-consuming process for the microorganisms; it reduces the energy gain and slows down cell growth. The same bacteria are responsible for aerobic and anaerobic hydrolysis. Therefore, the process of sludge destabilisation can be intensified considerably by making the whole organic fraction biologically available, i.e. by replacing the slow stage of enzymatic sludge hydrolysis by a chemical, thermal or mechanical stage. Sludge disintegration by one of these processes would intensify anaerobic degradation, reduce sludge volumes and enhance biogas production. (orig.) [German] Die anaerobe Stabilisierung ist anerkannte Regel der Technik und fuehrt zu einem teilweisen Abbau der organischen Bestandteile des Rohschlammes. Eine Verminderung der zu entsorgenden Schlammmasse geht damit einher. Wesentlicher Nachteil der anaeroben Klaerschlammstabilisierung ist die geringe Umsatzleistung dieses Prozesses. Dem Aufschluss der Feststoffe/grossen Molekuele des Schlammes kommt eine Schluesselrolle zu: die Hydrolyse der Rohschlammfeststoffe stellt den geschwindigkeitsbestimmenden Teilschritt des aneroben Abbauprozesses dar. Nach den gegenwaertigen Vorstellungen greifen von den fermentierenden Mikroorganismen produzierte Exoenzyme das partikulaere Material an und loesen Monomere heraus. Die Herstellung der Exoenzyme ist fuer die Mikroorganismen energetisch sehr aufwendig und vermindert den Energiegewinn und damit das Zellwachstum. Die Hydrolyse ist unabhaengig davon, ob sie aerob oder anaerob erfolgt, sie wird von denselben Bakterien bewerkstelligt. Man kann sich demnach

  9. 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.

  10. Potential biogas production from sewage sludge: A case study of the sewage treatment plant at Kwame Nkrumah university of science and technology, Ghana

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Richard [Energy Systems Engineering Department, Koforidua Polytechnic, Box KF 981, Koforidua (Ghana); Brew-Hammond, Abeeku [Faculty of Mechanical and Agricultural Engineering, Kwame Nkrumah University of Science and Technology, Private Mail Bag, Kumasi (Ghana)

    2010-07-01

    Biogas generation is one of the most promising renewable energy sources in Ghana. Anaerobic digestion is one of the effective ways of generating biogas. Anaerobic digestion is also a reliable method for wastewater treatment and the digestion the effluent can be used as fertilizer to enhance the fertility of the soil. This paper looks at the possibility of constructing a biogas plant at the KNUST sewage treatment plant tapping its feedstock the sludge at the Primary Sedimentation Tank to generate biogas. A laboratory experiment was done to determine the faecal sludge quality. The flowrate of the sludge was estimated based on the number of times the penstocks (valves) are operated to desludge the sewage which also depends on whether the university is on vacation (35.72 m3/day) or in session (71.44 m3/day). These parameters were used to determine the biogas potential of the sewage using 10, 20 and 30 days retention time for plant sizes of 540 m3, 1100m3 and 1600 m3 respectively. It was estimated that 170,719 m3, 341,858 m3 and 419,458 m3 of methane can be produced in a year and the power production was estimated to be 50 kW, 100 kW and 120 kW for the 540 m3, 1100m3 and 1600 m3 digester sizes respectively.

  11. Environmental & economic life cycle assessment of current & future sewage sludge to energy technologies.

    Science.gov (United States)

    Mills, N; Pearce, P; Farrow, J; Thorpe, R B; Kirkby, N F

    2014-01-01

    The UK Water Industry currently generates approximately 800GWh pa of electrical energy from sewage sludge. Traditionally energy recovery from sewage sludge features Anaerobic Digestion (AD) with biogas utilisation in combined heat and power (CHP) systems. However, the industry is evolving and a number of developments that extract more energy from sludge are either being implemented or are nearing full scale demonstration. This study compared five technology configurations: 1 - conventional AD with CHP, 2 - Thermal Hydrolysis Process (THP) AD with CHP, 3 - THP AD with bio-methane grid injection, 4 - THP AD with CHP followed by drying of digested sludge for solid fuel production, 5 - THP AD followed by drying, pyrolysis of the digested sludge and use of the both the biogas and the pyrolysis gas in a CHP. The economic and environmental Life Cycle Assessment (LCA) found that both the post AD drying options performed well but the option used to create a solid fuel to displace coal (configuration 4) was the most sustainable solution economically and environmentally, closely followed by the pyrolysis configuration (5). Application of THP improves the financial and environmental performance compared with conventional AD. Producing bio-methane for grid injection (configuration 3) is attractive financially but has the worst environmental impact of all the scenarios, suggesting that the current UK financial incentive policy for bio-methane is not driving best environmental practice. It is clear that new and improving processes and technologies are enabling significant opportunities for further energy recovery from sludge; LCA provides tools for determining the best overall options for particular situations and allows innovation resources and investment to be focused accordingly. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. 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)

  13. 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.

  14. 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.

  15. Application of sewage sludge and intermittent aeration strategy to the bioremediation of DDT- and HCH-contaminated soil.

    Science.gov (United States)

    Liang, Qi; Lei, Mei; Chen, Tongbin; Yang, Jun; Wan, Xiaoming; Yang, Sucai

    2014-08-01

    Adding organic amendments to stimulate the biodegradation of pesticides is a subject of ongoing interest. The effect of sewage sludge on the bioremediation of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) contaminated soil was investigated in bench scale experiments, and intermittent aeration strategy was also used in this study to form an anaerobic-aerobic cycle. Bioremediation of DDT and HCH was enhanced with the addition of sewage sludge and the intermittent aeration. The removal rates of HCH and DDT were raised by 16.8%-80.8% in 10 days. Sewage sludge increased the organic carbon content from 6.2 to 218 g/kg, and it could also introduce efficient degradation microbes to soil, including Pseudomonas sp., Bacillus sp. and Sphingomonas sp. The unaerated phase enhanced the anaerobic dechlorination of DDT and HCH, and anaerobic removal rates of β-HCH, o,p'-DDT and p,p'-DDT accounted for more than 50% of the total removal rates, but the content of α-HCH declined more in the aerobic phase. Copyright © 2014. Published by Elsevier B.V.

  16. Effects of sewage sludge addition to Norway spruce seedlings on nitrogen availability and soil fauna in clear-cut areas

    International Nuclear Information System (INIS)

    Nieminen, Jouni K.; Räisänen, Mikko

    2013-01-01

    Anaerobically digested and composted sewage sludge (CSS) has been suggested to be a slow-release fertilizer in forestry and an alternative to quick-release inorganic fertilizers. The effects of CSS with or without added carbohydrate on inorganic nitrogen availability and on soil animals were tested in two Norway spruce plantations. Half of the seedlings were individually fertilized with CSS, and the rest were left as controls. Solid sucrose was added to half of the fertilized and untreated seedlings. Soil samples were taken in the autumn in the first and the second year after the treatments. CSS increased soil NH 4 –N (2100%), the proportion of soil NO 3 –N, and the N concentration of spruce needles. CSS greatly reduced the abundances of enchytraeids, tardigrades and collembolans, but increased the proportion and abundance of bacterial-feeding nematodes irrespective of carbohydrate addition. A better stabilization method needs to be developed before CSS can be used as a forest fertilizer. -- Highlights: •Spruces were fertilized with anaerobically digested and composted sewage sludge (CSS). •CSS increased soil N, proportion of NO 3 –N, and N concentration of spruce needles. •CSS reduced the abundances of enchytraeids, tardigrades and collembolans. •CSS increased the proportion and abundance of bacterial-feeding nematodes. •Sucrose did not reduce N pools or counteract negative CSS effects on soil animals. -- Composting and carbohydrate addition do not mitigate the harmful effects of anaerobically digested sewage sludge in boreal forest soil

  17. Analysis on carbon dioxide emission reduction during the anaerobic synergetic digestion technology of sludge and kitchen waste: Taking kitchen waste synergetic digestion project in Zhenjiang as an example.

    Science.gov (United States)

    Guo, Qia; Dai, Xiaohu

    2017-11-01

    With the popularization of municipal sewage treatment facilities, the improvement of sewage treatment efficiency and the deepening degree of sewage treatment, the sludge production of sewage plant has been sharply increased. Carbon emission during the process of municipal sewage treatment and disposal has become one of the important sources of greenhouse gases that cause greenhouse effect. How to reduce carbon dioxide emissions during sewage treatment and disposal process is of great significance for reducing air pollution. Kitchen waste and excess sludge, as two important organic wastes, once uses anaerobic synergetic digestion technology in the treatment process can on the one hand, avoid instability of sludge individual anaerobic digestion, improve sludge degradation rate and marsh gas production rate, and on the other hand, help increase the reduction of carbon dioxide emissions to a great extent. The paper uses material balance method, analyzes and calculates the carbon dioxide emissions from kitchen waste and sludge disposed by the anaerobic synergetic digestion technology, compares the anaerobic synergetic digestion technology with traditional sludge sanitary landfill technology and works out the carbon dioxide emission reductions after synergetic digestion. It takes the kitchen waste and sludge synergetic digestion engineering project of Zhenjiang city in Jiangsu province as an example, makes material balance analysis using concrete data and works out the carbon dioxide daily emission reductions. The paper analyzes the actual situation of emission reduction by comparing the data, and found that the synergetic digestion of kitchen waste and sludge can effectively reduce the carbon dioxide emission, and the reduction is obvious especially compared with that of sludge sanitary landfill, which has a certain effect on whether to promote the use of the technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. 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)

  19. 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.

  20. 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)

  1. 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.

  2. 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

  3. Co-digestion of sewage sludge with glycerol to boost biogas production

    International Nuclear Information System (INIS)

    Fountoulakis, M.S.; Petousi, I.; Manios, T.

    2010-01-01

    The feasibility of adding crude glycerol from the biodiesel industry to the anaerobic digesters treating sewage sludge in wastewater treatment plants was studied in both batch and continuous experiments at 35 o C. Glycerol addition can boost biogas yields, if it does not exceed a limiting 1% (v/v) concentration in the feed. Any further increase of glycerol causes a high imbalance in the anaerobic digestion process. The reactor treating the sewage sludge produced 1106 ± 36 ml CH 4 /d before the addition of glycerol and 2353 ± 94 ml CH 4 /d after the addition of glycerol (1% v/v in the feed). The extra glycerol-COD added to the feed did not have a negative effect on reactor performance, but seemed to increase the active biomass (volatile solids) concentration in the system. Batch kinetic experiments showed that the maximum specific utilization rate (μ max ) and the saturation constant (K S ) of glycerol were 0.149 ± 0.015 h -1 and 0.276 ± 0.095 g/l, respectively. Comparing the estimated values with the kinetics constants for propionate reported in the literature, it can be concluded that glycerol uptake is not the rate-limiting step during the process.

  4. 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

  5. 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.)

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. Soil and pasture P concentration in a Fraxinus excelsior L. silvopastoral system fertilised with different types of sewage sludge

    Science.gov (United States)

    Ferreiro-Domínguez, Nuria; Nair, Vimala; Rigueiro-Rodríguez, Antonio; Rosa Mosquera-Losada, María

    2015-04-01

    In Europe, sewage sludge should be stabilised before using as fertiliser in agriculture. Depending on the stabilisation process that is used, sewage sludge has different characteristics, nutrient contents and soil nutrient incorporation rates. Sewage sludge is usually applied on a plant-available N or total metal concentration basic, and therefore, P concentrations can be well above crop needs. Leaching of excess P can threaten surface and ground waters with eutrophication. In this context, recent studies have demonstrated that the implementation of agroforestry systems could reduce the P leaching risk compared with conventional agricultural systems due to the different localisation of tree and crop roots which enhance nutrient uptake. The aim of this study was to evaluate during three consecutive years the effect of municipal sewage sludge stabilised by anaerobic digestion, composting, and pelletisation on concentration of P in soil and pasture compared to control treatments (mineral and no fertilisation) in a silvopastoral system established under Fraxinus excelsior L. in Galicia (Spain). The results showed that at the beginning of the study, the fertilisation with mineral increased more the total and available P in soil than the fertilisation with sewage sludge probably because the sludge nutrient release rate is slower than those from mineral fertilisers. The increment of soil available P caused by the mineral fertiliser implied an improvement of the P concentration in the pasture. However, in the last year of the experiment it was observed a positive effect of the fertilisation with pelletised sludge on the concentration of P in pasture compared with the composted sludge and the mineral fertiliser probably due to the annual application of this type of sludge. Therefore, the establishment of silvopastoral systems and their fertilisation with pelletized sludge should be recommended because the pelletized sludge increases the concentration of P in the pasture and

  11. 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...

  12. Anaerobic digestion of cheese whey using an upflow anaerobic sludge blanket reactor: Pt. 3; Sludge and substrate profiles

    Energy Technology Data Exchange (ETDEWEB)

    Yan, J.Q.; Lo, K.V.; Liao, P.H. (British Columbia Univ., Vancouver (CA). Dept. of Bio-Resource Engineering)

    1990-01-01

    Anaerobic treatment of cheese whey using a 17.5 litre upflow anaerobic sludge blanket reactor was investigated in the laboratory over a range of influent concentration from 4.5 to 38.1 g COD litre{sup -1} at a constant hydraulic retention time of 5 days. The results indicated that two sludge distribution regions, a sludge bed and a sludge blanket, as well as two distinct reaction phases, acidogenic and methanogenic, were formed. However, as the substrate loading was increased, the acidogenic region extended into the methanogenic region in the upper portion of the reactor until the whole region was acidogenic, leading to the failure of the reactor. (author).

  13. 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.

  14. Evaluation of emission of greenhouse gases from soils amended with sewage sludge.

    Science.gov (United States)

    Paramasivam, S; Fortenberry, Gamola Z; Julius, Afolabi; Sajwan, Kenneth S; Alva, A K

    2008-02-01

    Increase in concentrations of various greenhouse gases and their possible contributions to the global warming are becoming a serious concern. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in C and N, as soil amendments could contribute to the increase in emission of greenhouse gases such as methane (CH(4)) and nitrous oxide (N(2)O) into the atmosphere. Therefore, evaluation of flux of various greenhouse gases from soils amended with sewage sludge is essential to quantify their release into the atmosphere. Two soils with contrasting properties (Candler fine sand [CFS] from Florida, and Ogeechee loamy sand [OLS] from Savannah, GA) were amended with varying rates (0, 24.7, 49.4, 98.8, and 148.3 Mg ha(-1)) of 2 types of sewage sludge (industrial [ISS] and domestic [DSS] origin. The amended soil samples were incubated in anaerobic condition at field capacity soil water content in static chamber (Qopak bottles). Gas samples were extracted immediately after amending soils and subsequently on a daily basis to evaluate the emission of CH(4), CO(2) and N(2)O. The results showed that emission rates and cumulative emission of all three gases increased with increasing rates of amendments. Cumulative emission of gases during 25-d incubation of soils amended with different types of sewage sludge decreased in the order: CO(2) > N(2)O > CH(4). The emission of gases was greater from the soils amended with DSS as compared to that with ISS. This may indicate the presence of either low C and N content or possible harmful chemicals in the ISS. The emission of gases was greater from the CFS as compared to that from the OLS. Furthermore, the results clearly depicted the inhibitory effect of acetylene in both soils by producing more N(2)O and CH(4) emission compared to the soils that did not receive acetylene at the rate of 1 mL g(-1) soil. Enumeration of microbial population by fluorescein diacetate

  15. 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

  16. Optimization of up-flow anaerobic sludge blanket reactor for ...

    African Journals Online (AJOL)

    Optimization of up-flow anaerobic sludge blanket reactor for treatment of composite ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search ... Granules grown in the bottom part of UASB reactor were more compact and tense ...

  17. The influence of aerobic sludge retention time on anaerobic co ...

    African Journals Online (AJOL)

    GREGO

    2007-04-02

    Apr 2, 2007 ... INTRODUCTION. In developing countries such as China, secondary waste- ..... co-digestion product of azo dye of TDP wastewater. (Razo-Flores et al., .... sludge disintegration for improving anaerobic stabilization. Water. Res.

  18. Anaerobic bioleaching of metals from waste activated sludge

    KAUST Repository

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

    2015-01-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether

  19. 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.

  20. Hybrid life-cycle environmental and cost inventory of sewage sludge treatment and end-use scenarios: a case study from China.

    Science.gov (United States)

    Murray, Ashley; Horvath, Arpad; Nelson, Kara L

    2008-05-01

    Sewage sludge management poses environmental, economic, and political challenges for wastewater treatment plants and municipalities around the globe. To facilitate more informed and sustainable decision making, this study used life-cycle inventory (LCI) to expand upon previous process-based LCIs of sewage sludge treatmenttechnologies. Additionally, the study evaluated an array of productive end-use options for treated sewage sludge, such as fertilizer and as an input into construction materials, to determine how the sustainability of traditional manufacturing processes changes with sludge as a replacement for other raw inputs. The inclusion of the life-cycle of necessary inputs (such as lime) used in sludge treatment significantly impacts the sustainability profiles of different treatment and end-use schemes. Overall, anaerobic digestion is generally the optimal treatment technology whereas incineration, particularly if coal-fired, is the most environmentally and economically costly. With respect to sludge end use, offsets are greatest for the use of sludge as fertilizer, but all of the productive uses of sludge can improve the sustainability of conventional manufacturing practices. The results are intended to help inform and guide decisions about sludge handling for existing wastewater treatment plants and those that are still in the planning phase in cities around the world. Although additional factors must be considered when selecting a sludge treatment and end-use scheme, this study highlights how a systems approach to planning can contribute significantly to improving overall environmental sustainability.

  1. Biogas production as affected by heavy metals in the anaerobic digestion of sludge

    Directory of Open Access Journals (Sweden)

    Hussein I. Abdel-Shafy

    2014-12-01

    The sewage sludge samples were separated from the sewage water of the pilot plant at the National Research Centre, TDC site. The effect of heavy metals on the biogas production of the anaerobic digester was studied. The inhibitory effect on the biogas production and toxic level of metals was determined in this study. The general ranking of heavy metal toxicity appears to be Hg > Cd > Cr (III. The present investigation reveals that heavy metals in addition to the anaerobic digester decreased the biogas production as an indication of efficiency of the process. A significant decrease in gas production and volatile organic matter removal was obtained. It was also noted that an accumulation of organic acid intermediates was obtained as a result of methanogenic bacterial inhibition. This accumulation was limited during the pulse feed of metals. This is due to the rapid poisoning of the active bacterial forms in the digester.

  2. 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.

  3. Electrokinetic copper and iron migration in anaerobic granular sludge

    NARCIS (Netherlands)

    Virkutyte, J.; Sillanpää, M.J.; Lens, P.N.L.

    2006-01-01

    The application of low-level direct electric current (0.15 mA cm¿2) as an electrokinetic technique to treat copper-contaminated mesophilic anaerobic granular sludge was investigated. The sludge was obtained from a full scale UASB reactor treating paper-mill wastewater and was artificially

  4. 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.

  5. 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.

  6. 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

  7. Ultraviolet radiation is feasible alternative for desinfeting of aerobic and anaerobic treatment systems sewage in Brazil

    International Nuclear Information System (INIS)

    Daniel, Luis Antonio; Campos, Jose Roberto

    1993-01-01

    This works shows desinfecting results employing ultraviolet radiation to wastes of sewage treatment station on true scales. Wastes of anaerobic, facultative and maturation pools, septic tank and anaerobic reactor were disinfected. It was found a inactive efficiency to coliforms higher than 99.9%. Safe ultraviolet desinfecting is technically applicable to wastes of sewage treatment station applying aerobic or anaerobic process

  8. 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

  9. 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.

  10. Characteristics of residues from thermally treated anaerobic sludges

    International Nuclear Information System (INIS)

    Friedman, A.A.; Smith, J.E.; De Santis, J.; Ptak, T.; Ganley, R.C.

    1988-01-01

    Sludge management and disposal are probably the most difficult and expensive operations involved in wastewater treatment today. To minimize final disposal costs many waste treatment facilities practice some form of anaerobic digestion and dewatering to reduce the volume and offensiveness of their by-product sludges. One potential alternative for reducing sludge volumes consists of high temperature, partial oxidation of these previously digested sludges (PDS) and subsequent anaerobic biological conversion of resulting soluble organics to methane. This paper describes solids destruction, residue characteristics and biodegradability factors that should be considered in the design of liquid thermal treatment processes for the management of anaerobic sludges. To date only very limited information is available concerning the suitability of thermally treated PDS to serve as a substrate for the generation of methane. The primary objective of this research was to determine the feasibility of producing methane efficiently from the residual VSS in anaerobically digested sludges. Secondary goals were to establish the ''best'' conditions for thermal treatment for solubilizing PDS, to observe the effect of the soluble products on methanogenesis and to evaluate process sidestreams for dewaterability and anaerobic biodegradability

  11. 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

  12. Experimental continuous sludge microwave system to enhance dehydration ability and hydrogen production from anaerobic digestion of sludge.

    Science.gov (United States)

    Zhou, Cuihong; Huang, Xintong; Zeng, Meng

    2018-05-01

    Dehydrating large amounts of sludge produced by sewage treatment plants is difficult. Microwave pretreatment can effectively and significantly improve the dewaterability and hydrogen production of sludge subjected to anaerobic digestion. The aim of this study was to investigate the effects of different microwave conditions on hydrogen production from anaerobic digestion and dewaterability of sludge. Based on an analysis of the electric field distribution, a spiral reactor was designed and a continuous microwave system was built to conduct intermittent and continuous experiments under different conditions. Settling Volume, Capillary Suction Time, particle size, and moisture content of the sludge were measured. The results show that sludge pretreatment in continuous experiments has equally remarkable dehydration performance as in intermittent experiments; the minimum moisture content was 77.29% in the intermittent experiment under a microwave power of 300W and an exposure time of 60sec, and that in the continuous experiment was 77.56% under a microwave power of 400W and an exposure time of 60sec. The peak measured by Differential Scanning Calorimeter appeared earliest under a microwave power of 600W and an exposure time of 180sec. The heat flux at the peak was 4.343W/g, which is relatively small. This indicates that microwave pretreatment induced desirable effects. The maximum yield of hydrogen production was 7.967% under the conditions of microwave power of 500W, exposure time of 120sec, and water bath at 55°C. This research provides a theoretical and experimental basis for the development of a continuous microwave sludge-conditioning system. Copyright © 2017. Published by Elsevier B.V.

  13. 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

  14. 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...

  15. 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.

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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...

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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...

  8. 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

  9. 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.)

  10. 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.

  11. 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.

  12. Quantification of viable but nonculturable Salmonella spp. and Shigella spp. during sludge anaerobic digestion and their reactivation during cake storage.

    Science.gov (United States)

    Fu, B; Jiang, Q; Liu, H-B; Liu, H

    2015-10-01

    The presence of viable but nonculturable (VBNC) bacterial pathogens which often fail to be detected by cultivation and can regain the cultivability if the living conditions improve were reported. The objective of this study was to determine the occurrence of VBNC Salmonella spp. and Shigella spp. in the biosolids during anaerobic digestion and its reactivation during the cake storage. The occurrence of VBNC Salmonella spp. and Shigella spp. during mesophilic, temperature-phased, thermophilic anaerobic digestion of sewage sludge and the subsequent storage were studied by RT-qPCR and most probable number (MPN) method. The VBNC incidence of Salmonella spp. and Shigella spp. during thermophilic digestion was four orders of magnitude higher than those of mesophilic digestion. Accordingly, higher resuscitation ratio of VBNC pathogens was also achieved in thermophilic digested sludge. As a result, the culturable Salmonella typhimurium contents in thermophilic digested sludge after cake storage were two orders of magnitude higher than mesophilic digestion. Both quantitative PCR and reverse transcription quantitative PCR assay results showed the two bacterial counting numbers remained stable throughout the cake storage. The results indicate that the increase in the culturable Salmonella spp. and Shigella spp. after centrifugal dewatering was attributed to the resuscitation from the VBNC state to the culturable state. Thermophilic anaerobic digestion mainly induced Salmonella spp. and Shigella spp. into VBNC state rather than killed them, suggesting that the biological safety of sewage sludge by temperature-phased anaerobic digestion should be carefully assessed. © 2015 The Society for Applied Microbiology.

  13. 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.

  14. 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)

  15. Fate and distribution of pharmaceuticals in wastewater and sewage sludge of the conventional activated sludge (CAS) and advanced membrane bioreactor (MBR) treatment.

    Science.gov (United States)

    Radjenović, Jelena; Petrović, Mira; Barceló, Damià

    2009-02-01

    case of loratidine the experimentally determined sorption coefficients (Kds) were in the range 2214-3321 L/kg (mean). The results obtained for the solid phase indicated that MBR wastewater treatment yielding higher biodegradation rate could reduce the load of pollutants in the sludge. Also, the overall output load in the aqueous and solid phase of the investigated WWTP was calculated, indicating that none of the residual pharmaceuticals initially detected in the sewage sludge were degraded during the anaerobic digestion. Out of the 26 pharmaceutical residues passing through the WWTP, 20 were ultimately detected in the treated sludge that is further applied on farmland.

  16. [Gradient elevation of temperature startup experiment of thermophilic ASBR treating thermal-hydrolyzed sewage sludge].

    Science.gov (United States)

    Ouyang, Er-Ming; Wang, Wei; Long, Neng; Li, Huai

    2009-04-15

    Startup experiment was conducted for thermophilic anaerobic sequencing batch reactor (ASBR) treating thermal-hydrolyzed sewage sludge using the strategy of the step-wise temperature increment: 35 degrees C-->40 degrees C-->47 degrees C-->53 degrees C. The results showed that the first step-increase (from 35 degrees C to 40 degrees C) and final step-increase (from 47 degrees C to 53 degrees C) had only a slight effect on the digestion process. The second step-increase (from 40 degrees C to 47 degrees C) resulted in a severe disturbance: the biogas production, methane content, CODeffluent and microorganism all have strong disturbance. At the steady stage of thermophilic ASBR treating thermal-hydrolyzed sewage sludge, the average daily gas production, methane content, specific methane production (CH4/CODinfluent), TCOD removal rate and SCOD removal rate were 2.038 L/d, 72.0%, 188.8 mL/g, 63.8%, 83.3% respectively. The results of SEM and DGGE indicated that the dominant species are obviously different at early stage and steady stage.

  17. 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

  18. Anaerobic bioleaching of metals from waste activated sludge

    KAUST Repository

    Meulepas, Roel J W

    2015-05-01

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

  19. Anaerobic bioleaching of metals from waste activated sludge

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  20. Anaerobic bioleaching of metals from waste activated sludge

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-01

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

  1. 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

  2. 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.

  3. 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.

  4. Dispersed plug flow model for upflow anaerobic sludge bed reactors with focus on granular sludge dynamics

    NARCIS (Netherlands)

    Kalyuzhnyi, S.V.; Fedorovich, V.V.; Lens, P.N.L.

    2006-01-01

    A new approach to model upflow anaerobic sludge bed (UASB)-reactors, referred to as a one-dimensional dispersed plug flow model, was developed. This model focusses on the granular sludge dynamics along the reactor height, based on the balance between dispersion, sedimentation and convection using

  5. 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.

  6. 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

  7. 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.

  8. 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.)

  9. 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)

  10. 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.

  11. Anaerobic treatment of domestic sewage in modified septic tanks at low temperature.

    Science.gov (United States)

    Chen, Zhiqiang; Wen, Qinxue; Guan, Huabin; Bakke, Rune; Ren, Nanqi

    2014-01-01

    Three laboratory-scale septic tanks, an anaerobic baffled reactor (ABR)-septic tank (R1), a Yuhuan drawing three-dimensional-carrier-septic tank (R2) and a conventional septic tank (R3), were operated in parallel over half a year under hydraulic retention times (HRTs) of 36, 24 and 12 h, with a sewage temperature of 16 degrees C. The removal efficiencies of total chemical oxygen demand (CODtot) achieved in R1 and R2 increased by 14%, 21% and 12% and 18%, 3% and 16%, respectively, under three different HRTs, as compared to those in R3. The total nitrogen and phosphorus removal efficiencies were negligible. R1 sludges had a higher specific methane production rate as compared to that of R2 and R3 sludges. The results indicated that the two modified septic tanks can improve the performance in terms of COD and total solids removal, both were suitable technologies for domestic sewage (pre) treatment at low temperature in northern China.

  12. 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.

  13. Effects of palm oil mill effluent (POME) anaerobic sludge from 500 m ...

    African Journals Online (AJOL)

    In this study, co-composting of pressed-shredded empty fruit bunches (EFB) and palm oil mill effluent (POME) anaerobic sludge from 500 m3 closed anaerobic methane digested tank was carried out. High nitrogen and nutrients content were observed in the POME anaerobic sludge. The sludge was subjected to the ...

  14. Effect of gamma-irradiation pretreatment on improvement of anaerobic digestive characteristic of sludge

    International Nuclear Information System (INIS)

    Mou Yanyan; Yuan Shoujun; Yu Xin; Zheng Zheng; Cui Lei; Zhao Yongfu

    2005-01-01

    A comparative study was made about main anaerobic digestive characteristics of sludge which was subjected to a 60 Co gamma-irradiation pretreatment. The results showed the gamma-irradiation pretreatment can clearly improve anaerobic digestibility of sludge and pick up the anaerobic digestion speed of sludge. (authors)

  15. A Simple and Rapid Method to Evaluate Potentially Mineralizable Nitrogen in Sewage Sludge Amended Calcareous Soils

    Directory of Open Access Journals (Sweden)

    Yazdan Lotfi

    2005-06-01

    Full Text Available Potentially mineralizable nitrogen (PMN can be usually considered as labile nitrogen. Measurement of PMN is expensive and time consuming; therefore, a simpler and more rapid alternative may facilitate routine laboratory analysis. The objective of this study was to determine the relationship between PMN and biological index of nitrogen availability (BINA. The studied soil was previously treated with 0, 25, and 100 tons ha-1 of sewage sludge with 0, 1, 2 and 3 consecutive years of application. Soil samples were taken 6 months after the latest application. PMN was measured according to Stanford and Smith procedure (20 weeks of aerobic incubation with 2 weeks leaching intervals and BINA measured as described by Bundy and Meisinger (7 days of anaerobic incubation at 40˚ C followed by extraction of NH4+. Results showed that PMN was significantly correlated with BINA (r = 0.938, P

  16. Environmental assessment of the Sibiu County, Romania: proposal for sewage sludge and OFMSW management

    Directory of Open Access Journals (Sweden)

    Trombin Gloria

    2017-01-01

    Full Text Available The aim of the work is to assess current solid waste management (SWM and wastewater treatment (WWT in the county of Sibiu, Romania. Sibiu is a region where industrialization and tourism are spreading constantly, while pollution monitoring and the introduction of circular economy (CE principles are still lacking. The environmental issues are mostly due to the absence of reliable sanitation systems, in particular for what concerns sewage sludge treatment. Moreover, Organic fraction from selective collection of municipal solid waste is still missing, since it is disposed of directly to landfill, increasing environmental pollution and contributing considerably to global warming. As a result, SWM and WWT should be improved at the same time, as sludge requires specific handlings in order to be safety disposed. The objective of the study is to investigate the introduction of affordable technological facilities able to treat sludge and the organic fraction of municipal solid waste, recovering, at least, the energy required for the working phase of the treatment plants. Anaerobic digestion resulted viable, but the organic fraction full stream collection seems to be the only way to have a significant energy recovery. From the financial point of view, the feasibility of this co-treatment option could count on specific opportunities that Romania has in the frame of the European Union context.

  17. Aged refuse enhances anaerobic digestion of waste activated sludge.

    Science.gov (United States)

    Zhao, Jianwei; Gui, Lin; Wang, Qilin; Liu, Yiwen; Wang, Dongbo; Ni, Bing-Jie; Li, Xiaoming; Xu, Rui; Zeng, Guangming; Yang, Qi

    2017-10-15

    In this work, a low-cost alternative approach (i.e., adding aged refuse (AR) into waste activated sludge) to significantly enhance anaerobic digestion of sludge was reported. Experimental results showed that with the addition dosage of AR increasing from 0 to 400 mg/g dry sludge soluble chemical oxygen demand (COD) increased from 1150 to 5240 mg/L at the digestion time of 5 d, while the maximal production of volatile fatty acids (VFA) increased from 82.6 to 183.9 mg COD/g volatile suspended solids. Although further increase of AR addition decreased the concentrations of both soluble COD and VFA, their contents in these systems with AR addition at any concentration investigated were still higher than those in the blank, which resulted in higher methane yields in these systems. Mechanism studies revealed that pertinent addition of AR promoted solubilization, hydrolysis, and acidogenesis processes and did not affect methanogenesis significantly. It was found that varieties of enzymes and anaerobes in AR were primary reason for the enhancement of anaerobic digestion. Humic substances in AR benefited hydrolysis and acidogenesis but inhibited methanogenesis. The effect of heavy metals in AR on sludge anaerobic digestion was dosage dependent. Sludge anaerobic digestion was enhanced by appropriate amounts of heavy metals but inhibited by excessive amounts of heavy metals. The relative abundances of microorganisms responsible for sludge hydrolysis and acidogenesis were also observed to be improved in the system with AR addition, which was consistent with the performance of anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. 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.

  19. Sludge granulation during anaerobic treatment of pre-hydrolysed ...

    African Journals Online (AJOL)

    An upflow anaerobic sludge bed (UASB) digester was operated at different hydraulic retention times (HRT) ranging from 26.7 h to 2.2 h, while the organic load rate (OLR) ranged from 0.9 to 7.3 kgCOD/m3·d. Sludge granulation was observed after day 150 of operation, at an HRT of 3.4 h, when small granules of less than 2 ...

  20. 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)

  1. 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.

  2. 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.

  3. The phenomenon of granulation of anaerobic sludge

    NARCIS (Netherlands)

    Hulshoff Pol, L.

    1989-01-01

    Successful high-rate anaerobic wastewater treatment can only be accomplished when the slowgrowing anaerobic biomass is efficiently held back in the anaerobic treatment system. This biomass retention can be achieved in various ways including immobilization of the organisms on fixed materials

  4. 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.

  5. 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

  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. Anaerobic digestion of cheese whey using up-flow anaerobic sludge blanket reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yan, J.Q.; Lo, K.V.; Liao, P.H.

    1989-01-01

    Anaerobic treatment of cheese whey using a 17.5-litre up-flow anaerobic sludge blanket reactor was investigated in the laboratory. The reactor was studied over a range of influent concentration from 4.5 to 38.1 g chemical oxygen demand per litre at a constant hydraulic retention time of 5 days. The reactor start-up and the sludge acclimatization were discussed. The reactor performance in terms of methane production, volatile fatty acids conversion, sludge net growth and chemical oxygen demand reduction were also presented in this paper. Over 97% chemical oxygen demand reduction was achieved in this experiment. At the influent concentration of 38.1 g chemical oxygen demand per litre, an instability of the reactor was observed. The results indicated that the up-flow anaerobic sludge blanket reactor process could treat cheese whey effectively.

  9. 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

  10. Biomass stabilization in the anaerobic digestion of wastewater sludges

    Energy Technology Data Exchange (ETDEWEB)

    Arnaiz, C. [Universidad de Sevilla, Dept. de Ingenieria Quimica y Ambiental, Sevilla (Spain); Gutierrez, J.C. [Universidad Pablo de Olavide, Dept. de Ciencias Ambientales, Sevilla (Spain); Lebrato, J. [Universidad de Sevilla, Grupo Tratamiento de Aguas Residuales, Sevilla (Spain)

    2005-07-01

    Sludge stabilization processes include both volatile solid destruction and biomass stabilization. Traditionally, both processes have been considered together, in such a way that, when volatile solid destruction is achieved, the biomass is considered stabilized. In this study, volatile solids reduction and biomass stabilization in the anaerobic digestion of primary, secondary and mixed sludges from municipal wastewater treatment plants were researched in batch cultures by measurements of suspended solids and suspended lipid-phosphate. The estimated kinetic constants were higher in all sludge types tested for the biomass stabilization process, indicating that volatile solids destruction and biomass stabilization are not parallel processes, since the latter one is reached before the former. (Author)

  11. Effect of alkaline addition on anaerobic sludge digestion with combined pretreatment of alkaline and high pressure homogenization.

    Science.gov (United States)

    Fang, Wei; Zhang, Panyue; Zhang, Guangming; Jin, Shuguang; Li, Dongyi; Zhang, Meixia; Xu, Xiangzhe

    2014-09-01

    To improve anaerobic digestion efficiency, combination pretreatment of alkaline and high pressure homogenization was applied to pretreat sewage sludge. Effect of alkaline dosage on anaerobic sludge digestion was investigated in detail. SCOD of sludge supernatant significantly increased with the alkaline dosage increase after the combined pretreatment because of sludge disintegration. Organics were significantly degraded after the anaerobic digestion, and the maximal SCOD, TCOD and VS removal was 73.5%, 61.3% and 43.5%, respectively. Cumulative biogas production, methane content in biogas and biogas production rate obviously increased with the alkaline dosage increase. Considering both the biogas production and alkaline dosage, the optimal alkaline dosage was selected as 0.04 mol/L. Relationships between biogas production and sludge disintegration showed that the accumulative biogas was mainly enhanced by the sludge disintegration. The methane yield linearly increased with the DDCOD increase as Methane yield (ml/gVS)=4.66 DDCOD-9.69. Copyright © 2014 Elsevier Ltd. All rights reserved.

  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. Comparison between ozone and ultrasound disintegration on sludge anaerobic digestion.

    Science.gov (United States)

    Braguglia, C M; Gianico, A; Mininni, G

    2012-03-01

    This paper deals with the comparison of ultrasound (mechanical) and ozone (chemical) pre-treatment on the performances of excess sludge semi-continuous digestion. Sludge solubilisation has been investigated by varying specific energy input. For each pre-treatment, long anaerobic digestion tests were carried out by two parallel digesters: one reactor, as control unit, was fed with untreated waste activated sludge, and the other one was fed with disintegrated sludge. To evaluate and compare the efficacy of both pre-treatments, the specific energy was maintained approximately the same. The digestion tests were carried out to investigate the feasibility of anaerobic digestion performance (total biogas production, volatile solids removal, sludge dewaterability) and to assess the heat balance. Results obtained from the digestion of sonicated sludge at 4% disintegration degree (≈ 2500 kJ/kg TS) showed that the ultrasound pre-treatment may be effective both in increasing VS destruction (+19%) and cumulative biogas production (+26%). On the contrary, the digestion test with ozonized sludge (ozone dose of 0.05 g O(3)/g TS corresponding to ≈ 2000 kJ/kg TS) did not indicate a significant improvement on the digestion performances. By doubling the ozone dose an improvement in the organics removal and cumulative biogas production was observed. Relevant differences in terms of colloidal charge and filterability were discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  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. Persistence of perfluoroalkylated substances in closed bottle tests with municipal sewage sludge.

    Science.gov (United States)

    Sáez, Monica; de Voogt, Pim; Parsons, John R

    2008-09-01

    Perfluoroalkylated substances (PFAS) are chemicals with completely fluorinated alkyl chains. The specific properties of the F-C bond give PFAS a high stability and make them very useful in a wide range of applications. PFAS also pose a potential risk to the environment and humans because they have been recently characterized as persistent, bioaccumulative, and toxic. The objective of this work is to study the bacterial degradation of PFAS under aerobic and anaerobic conditions in municipal sewage sludge as a contribution toward understanding their environmental fate and behavior. Bacterial communities from sewage sludge were exposed to a mixture of PFAS under aerobic or anaerobic conditions. Individual PFAS concentrations were determined in the experiment media at different exposure times using liquid chromatography-mass spectrometry analysis after extraction with solid-phase extraction. The PFAS analyses of samples of sludge showed repeatable replicate results, allowing a reliable quantification of the different groups of PFAS analyzed. No conclusive evidence for PFAS degradation was observed under the experimental conditions tested in this work. Reduction in concentrations, however, was observed for some PFAS in sludge under aerobic conditions. The largest concentration decrease occurred for the fluorotelomer alcohols (FTOHs), especially for the 8:2 FTOH, which have been described as biodegradable in the literature. However, this concentration decrease could be due to different causes: sorption to glass, septa, or matrix components, as well as bacterial activity. Therefore, it is not certain that biodegradation occurred. PFAS are very recalcitrant chemicals, especially when fully fluorinated. Although some decreases in concentration have been observed for some PFAS, such as the FTOHs, there is no conclusive evidence for biodegradation. It can be concluded that the PFAS tested in these experiments are non-biodegradable under these experimental conditions. Since

  2. 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.

  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. 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.

  5. Fermentative biohydrogen and biomethane co-production from mixture of food waste and sewage sludge: Effects of physiochemical properties and mix ratios on fermentation performance

    International Nuclear Information System (INIS)

    Cheng, Jun; Ding, Lingkan; Lin, Richen; Yue, Liangchen; Liu, Jianzhong; Zhou, Junhu; Cen, Kefa

    2016-01-01

    Highlights: • Microanalyses revealed food waste had more gelatinized organics and less mineral ash. • Mixed food waste and sewage sludge at 5 ratios were used for H_2 and CH_4 co-production. • Highest H_2 yield of 174.6 mL/gVS was achieved when food waste:sewage sludge was 3:1. • Co-fermentation enhanced carbon conversion by strengthening hydrolysis of substrates. • Energy yield rose from 1.9 kJ/gVS in H_2 to 11.3 kJ/gVS in H_2 and CH_4 co-production. - Abstract: The accumulation of increasingly generated food waste and sewage sludge is currently a heavy burden on environment in China. In this study, the physiochemical properties of food waste and sewage sludge were identified using scanning electron microscopy and Fourier transform infrared spectroscopy to investigate the effects on the fermentation performance in the co-fermentation of food waste and sewage sludge for biohydrogen production. The high gelatinized organic components in food waste, the enhanced bioaccessibility due to the dilution of mineral compounds in sewage sludge, and the balanced C/N ratio synergistically improved the fermentative biohydrogen production through the co-fermentation of food waste and sewage sludge at a volatile solids (VS) mix ratio of 3:1. The biohydrogen yield of 174.6 mL/gVS was 49.9% higher than the weighted average calculated from mono-fermentation of food waste and sewage sludge. Co-fermentation also strengthened the hydrolysis and acidogenesis of the mixture, resulting in a total carbon conversion efficiency of 63.3% and an energy conversion efficiency of 56.6% during biohydrogen production. After the second-stage anaerobic digestion of hydrogenogenic effluent, the energy yield from the mixed food waste and sewage sludge significantly increased from 1.9 kJ/gVS in the first-stage biohydrogen production to 11.3 kJ/gVS in the two-stage fermentative biohydrogen and biomethane co-production.

  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. 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)

  10. 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...

  11. 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

  12. 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

  13. 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.

  14. Zinc deprivation of methanol fed anaerobic granular sludge bioreactors

    NARCIS (Netherlands)

    Fermoso, F.G.; Collins, G.; Bartacek, J.; Lens, P.N.L.

    2008-01-01

    The effect of omitting zinc from the influent of mesophilic (30 degrees C) methanol fed upflow anaerobic sludge bed (UASB) reactors, and latter zinc supplementation to the influent to counteract the deprivation, was investigated by coupling the UASB reactor performance to the microbial ecology of

  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. 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.

  17. 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

  18. 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.

  19. 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

  20. 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...

  1. 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.

  2. 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.)

  3. 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

  4. 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

  5. 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.

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

    Directory of Open Access Journals (Sweden)

    Julita Karolina Milik

    2017-09-01

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

  7. 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.)

  8. 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.

  9. 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 ...

  10. 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.

  11. 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

  12. 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...

  13. The behaviour of pharmaceuticals in anaerobic digester sludge

    OpenAIRE

    Campbell, Alison

    2013-01-01

    Pharmaceuticals are biologically active compounds that may be consumed in hundreds of tonnes per year, and which are excreted into municipal sewerage systems. Many pharmaceuticals persist during sewage treatment, and significant environmental risk has been linked to incomplete removal of pharmaceuticals. Evaluation of this risk is important and should be as representative as possible, taking into consideration all significant exposure routes and removal processes. Sludge treatment processes a...

  14. 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)

  15. 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.)

  16. 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.

  17. 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.

  18. 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.

  19. 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).

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. Biogas Production Experimental Research by Using Sewage Sludge Loading with Biochar Additive

    Directory of Open Access Journals (Sweden)

    Vitalij Kolodynskij

    2017-09-01

    Full Text Available Biogas – ecological fuel, which is assigned to alternative energy sources. It should be noted, that biogas – renewable energy source, which does not require any specific climatic conditions or geographical position of a country. This power source is available and can be successfully produced and used in all countries of the world. The main components of biogas – methane CH4 and carbon monoxide CO2. This gas is formed under anaerobic conditions, when microorganisms decompose biodegradable biomass. In biological sciences biomass means a living matter content, expressed in grams per unit area. Meanwhile, in the energy sector, the definition of biomass is limited and biomass is characterized as fuel source, produced from plant materials and organic waste (food waste, wood, sludge, manure, vegetables, etc.. Currently, to produce biogas from biomass, bioreactors are used worldwide. However, in order to increase the quality and yield of biogas, in the world practice various bioload additives are used: vegetable waste, clay minerals, and a large amount of the protein-containing waste. The goal – to evaluate the impact of biochar on biogas quality and yield using sewage sludge load. It was found, that 10% biochar additive increased average CH4 concentration of 7.9%, reduced the CO2 concentration of 3–4% and totally removed H2S from biogas.

  6. 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.

  7. 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...

  8. 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.

  9. 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)

  10. Anaerobic biodegradability and treatment of grey water in upflow anaerobic sludge blanket (UASB) reactor.

    Science.gov (United States)

    Elmitwalli, Tarek A; Otterpohl, Ralf

    2007-03-01

    Feasibility of grey water treatment in an upflow anaerobic sludge blanket (UASB) reactor operated at different hydraulic retention time (HRT) of 16, 10 and 6h and controlled temperature of 30 degrees C was investigated. Moreover, the maximum anaerobic biodegradability without inoculum addition and maximum removal of chemical oxygen demand (COD) fractions in grey water were determined in batch experiments. High values of maximum anaerobic biodegradability (76%) and maximum COD removal in the UASB reactor (84%) were achieved. The results showed that the colloidal COD had the highest maximum anaerobic biodegradability (86%) and the suspended and dissolved COD had similar maximum anaerobic biodegradability of 70%. Furthermore, the results of the UASB reactor demonstrated that a total COD removal of 52-64% was obtained at HRT between 6 and 16 h. The UASB reactor removed 22-30% and 15-21% of total nitrogen and total phosphorous in the grey water, respectively, mainly due to the removal of particulate nutrients. The characteristics of the sludge in the UASB reactor confirmed that the reactor had a stable performance. The minimum sludge residence time and the maximum specific methanogenic activity of the sludge ranged between 27 and 93 days and 0.18 and 0.28 kg COD/(kg VS d).

  11. Improved Energy Recovery by Anaerobic Grey Water Sludge Treatment with Black Water

    NARCIS (Netherlands)

    Tervahauta, T.H.; Bryant, I.M.; Hernandez Leal, L.; Buisman, C.J.N.; Zeeman, G.

    2014-01-01

    This study presents the potential of combining anaerobic grey water sludge treatment with black water in an up-flow anaerobic sludge blanket (UASB) reactor to improve energy recovery within source-separated sanitation concepts. Black water and the mixture of black water and grey water sludge were

  12. 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...

  13. 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.)

  14. 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 ...

  15. 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...

  16. 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

  17. 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

  18. Microbial degradation of 4-monobrominated diphenyl ether with anaerobic sludge

    International Nuclear Information System (INIS)

    Shih, Yang-hsin; Chou, Hsi-Ling; Peng, Yu-Huei

    2012-01-01

    Highlights: ► BDE-3 was degraded with two anaerobes in different rates. ► Glucose addition augment the debromination efficiencies. ► Hydrogen gas was detected and relative microbes were identified. ► Extra-carbon source enhanced degradation partial due to H 2 -generation bacteria. - Abstract: Polybrominated diphenyl ethers (PBDEs) are widely used flame retardant additives for many plastic and electronic products. Owing to their ubiquitous distribution in the environment, multiple toxicity to humans, and increasing accumulation in the environment, the fate of PBDEs is of serious concern for public safety. In this study, the degradation of 4-monobrominated diphenyl ether (BDE-3) in anaerobic sludge and the effect of carbon source addition were investigated. BDE-3 can be degraded by two different anaerobic sludge samples. The by-products, diphenyl ether (DE) and bromide ions, were monitored, indicating the reaction of debromination within these anaerobic samples. Co-metabolism with glucose facilitated BDE-3 biodegradation in terms of kinetics and efficiency in the Jhongsing sludge. Through the pattern of amplified 16S rRNA gene fragments in denatured gradient gel electrophoresis (DGGE), the composition of the microbial community was analyzed. Most of the predominant microbes were novel species. The fragments enriched in BDE-3-degrading anaerobic sludge samples are presumably Clostridium sp. This enrichment coincides with the H 2 gas generation and the facilitation of debromination during the degradation process. Findings of this study provide better understanding of the biodegradation of brominated DEs and can facilitate the prediction of the fate of PBDEs in the environment.

  19. 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.

  20. 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

  1. 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.)

  2. Relationships between stability, maturity, water-extractable organic matter of municipal sewage sludge composts and soil functionality.

    Science.gov (United States)

    Sciubba, Luigi; Cavani, Luciano; Grigatti, Marco; Ciavatta, Claudio; Marzadori, Claudio

    2015-09-01

    Compost capability of restoring or enhancing soil quality depends on several parameters, such as soil characteristics, compost carbon, nitrogen and other nutrient content, heavy metal occurrence, stability and maturity. This study investigated the possibility of relating compost stability and maturity to water-extractable organic matter (WEOM) properties and amendment effect on soil quality. Three composts from municipal sewage sludge and rice husk (AN, from anaerobic wastewater treatment plants; AE, from aerobic ones; MIX, from both anaerobic and aerobic ones) have been analysed and compared to a traditional green waste compost (GM, from green manure, solid waste and urban sewage sludge). To this aim, WEOMs were characterized through chemical analysis; furthermore, compost stability was evaluated through oxygen uptake rate calculation and maturity was estimated through germination index determination, whereas compost impact on soil fertility was studied, in a lab-scale experiment, through indicators as inorganic nitrogen release, soil microbial biomass carbon, basal respiration rate and fluorescein di-acetate hydrolysis. The obtained results indicated that WEOM characterization could be useful to investigate compost stability (which is related to protein and phenol concentrations) and maturity (related to nitrate/ammonium ratio and degree of aromaticity) and then compost impact on soil functionality. Indeed, compost stability resulted inversely related to soil microbial biomass, basal respiration rate and fluorescein di-acetate hydrolysis when the products were applied to the soil.

  3. A Survey of Sludge Granulation Theories Under Anaerobic Conditions

    Directory of Open Access Journals (Sweden)

    Jalal Shayegan

    2011-01-01

    Full Text Available This paper surveys the different theories developed on anaerobic sludge granulation. The theories are generally categorized as physical, microbial, and thermodynamic approaches. In the physical approach to the granulation process, granulation is described by such physical conditions of the reactor as upflow velocity of gas and liquid streams, suspended solids in the effluent flow, and excess sludge removal. Microbial theories are based on the properties of specific organisms and on granule properties (granule structure and its microbiology. The thermodynamic approach studies such factors as hydrophobia, electrophoretic mobility, effective energy in granule adhesion process, and effect of proton transferring activities on bacterial membrane surfaces.

  4. Degradation of organic pollutants in sewage sludge by aerobic-thermophilic sludge treatment. Final report; Abbau organischer Schadstoffe im Klaerschlamm durch aerob-thermophile Schlammbehandlung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Prechtl, S.

    1999-07-01

    A process for reduction of organic polllutants in sewage sludge was to be developed and optimized. The organic fraction of the solid matter in sewage sludge containes more than 300 different pollutant. Apart from the substances classified in the Sewage Sludge Ordinance (dioxins/furans, PCB), there are others that have been considered relevant as well but for which no sufficient data base is available. The research project investigated whether aerobic-thermophilic treatment (AT) would improve the sewage sludge quality with regard to phthalates (di(2-ethylhexyl)phthalate, DEHP), PAH and 4-nonylphenol (4-NP, a degradation product of nonionic tensides). Pollutants were analzyed by HPLC and GC/MS. The concentration of DEHP and 4-NP was reduced by 70% resp. 50% in laboratory experiments with doped sludges and by 61% resp. 53% in undoped sludges. In semi-industrial tests, a 14% reduction was achieved for DEHP and a 68% reduction for 4-NP. In the case of pyrene, the degradation was up to 57% in the laboratory experiments and 22% in semi-industrial tests. A combined process of short-term anaerobic digestion and AT resulted in a 60% reduction in the case of DEHP. Up to anthracene, PAH were reduced as well. In the case of higher-condensed PAH (basic load in the ppb range) there was no clear result. In the case of 4-NP, the degradation effect was counterbalanced by the formation of new 4-NP from alkylphenol ethoxylates in both anaerobic and aerobic conditions. The results prove the correlation between sewage sludge hygienisation and the time of residue in the reactor system. No enterobacteriaceae were found after a treatment of 96 h, both in the semi-industrial and the laboratory reactors. In activated sludge, a phenol-degrading mixed bacteria culture could be isolated which was also capable of degrading 4-NP in thermophilic conditions. [German] Das Ziel des Forschungsvorhabens war die Entwicklung/Optimierung eines Verfahrens zur Reduktion organischer Schadstoffe im

  5. 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