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1
Choi, H. B., K. Y. Hwang, and E. B. Shin. "Effects on anaerobic digestion of sewage sludge pretreatment." Water Science and Technology 35, no. 10 (May 1, 1997): 207–11. http://dx.doi.org/10.2166/wst.1997.0384.
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This research investigates the effect of sludge pretreatment on the anaerobic digestion of waste-activated sludge (WAS). In the key of this sludge pretreatment process, bacteria in the WAS were ruptured by mechanical jet and smashed under pressurized conditions. The protein concentrations in the sludge varied significantly after pretreatment. Protein concentration increased according to jet times and pressure. In batch experiments, volatile solids (VS) removal efficiencies were 13∼50% when the WAS pretreated once under 30 bar was fed into an anaerobic digester with 2∼26 day retention time. In the same operating conditions, when intact WAS was fed into the digester, VS removal efficiencies were 2∼35%. Therefore, it is recognized that higher digestion efficiencies of the WAS were obtained through a mechanical pretreatment of sludge.
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Lebiocka, Magdalena, Agnieszka Montusiewicz, and Agnieszka Cydzik-Kwiatkowska. "Effect of Bioaugmentation on Biogas Yields and Kinetics in Anaerobic Digestion of Sewage Sludge." International Journal of Environmental Research and Public Health 15, no. 8 (August 10, 2018): 1717. http://dx.doi.org/10.3390/ijerph15081717.
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Bioaugmentation with a mixture of microorganisms (Bacteria and Archaea) was applied to improve the anaerobic digestion of sewage sludge. The study was performed in reactors operating at a temperature of 35 °C in semi-flow mode. Three runs with different doses of bioaugmenting mixture were conducted. Bioaugmentation of sewage sludge improved fermentation and allowed satisfactory biogas/methane yields and a biodegradation efficiency of more than 46%, despite the decrease in hydraulic retention time (HRT) from 20 d to 16.7 d. Moreover, in terms of biogas production, the rate constant k increased from 0.071 h−1 to 0.087 h−1 as doses of the bioaugmenting mixture were increased, as compared to values of 0.066 h−1 and 0.069 h−1 obtained with sewage sludge alone. Next-generation sequencing revealed that Cytophaga sp. predominated among Bacteria in digesters and that the hydrogenotrophic methanogen Methanoculleus sp. was the most abundant genus among Archaea.
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Neis, U., K. Nickel, and A. Tiehm. "Enhancement of anaerobic sludge digestion by ultrasonic disintegration." Water Science and Technology 42, no. 9 (November 1, 2000): 73–80. http://dx.doi.org/10.2166/wst.2000.0174.
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Biological cell lysis is known to be the rate limiting step of anaerobic sludge stabilization. Shear forces generated by high-power ultrasound can be used to disintegrate bacterial cells in sewage sludge. Thus the quantity of bioavailable dissolved organic substrate (Chemical Oxygen Demand) is significantly increased. As a result the subsequent sludge degradation is accelerated considerably. In our tests the fermentation process of sonicated waste activated sludge remained stable even at a very short digestion time of 4 days. The enhanced degradation rate resulted in a reduced volatile solids concentration of the digested sludges after the usual fermentation times.
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Al-Haddad, Saleh, Cynthia Kusin Okoro-Shekwaga, Louise Fletcher, and Miller Alonso Camargo-Valero. "The Impact of Enzymatic Hydrolysis of Sewage Sludge as a Pre-treatment for Dark Fermentation." International Journal of Environmental Science and Development 13, no. 6 (2022): 279–86. http://dx.doi.org/10.18178/ijesd.2022.13.6.1405.
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For many years, sewage sludge has been processed for methane production in anaerobic digestion reactors at wastewater treatment plants around the world. Sewage sludge is produced in large quantities and is rich in biodegradable organic materials, from which sugars (e.g., glucose) can be produced, recovered and used as a substrate to support hydrogen production through the Dark Fermentation (DF) process. DF is one of several methods used for bio-hydrogen production, whereby fermentative bacteria are used to hydrolyse organic substrates to produce hydrogen gas. Carbohydrates (sugars) is one of the main fermentable substrates for hydrogen production, and they are considered the most favourable substrate for fermentative bacteria (e.g., Clostridium bacteria). Although sewage sludge is rich in organic materials, still the complexity of its structure and low carbon/nitrogen ratio limits the bio-hydrogen production via DF processes. Therefore, this paper addresses the impact of Enzymatic Hydrolysis (EH) as a pre-treatment of sewage sludge on enhancing the biodegradability and glucose content in sewage sludge. The result shows that using the EH process as pre-treatment for sewage sludge, enhanced the glucose content in sewage sludge and converted some of the macro sewage flocs to easy digestible micro flocs (glucose). Therefore, the substrate being more favourable and easier to digest by bacteria in the DF reactor, enhanced the production of hydrogen and VFAs. More research needs to be done to find the optimum enzyme dosage, initial substrate concentration and operation temperature (especially when the enzyme is used inside the DF reactor).
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Mueller, R. F., and A. Steiner. "Inhibition of Anaerobic Digestion Caused by Heavy Metals." Water Science and Technology 26, no. 3-4 (August 1, 1992): 835–46. http://dx.doi.org/10.2166/wst.1992.0464.
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The severity of heavy metal inhibition on anaerobic digestion is dependent on the metal species and their dissolved concentration in the digester. The general sequence of inhibition on anaerobic digestion of municipal sewage sludge was found with Ni > Cu > Cd > Cr > Pb. Metal immobilization affinity in the sludge followed the reverse sequence. Due to sulfide production during digestion high quantities of heavy metals are precipitating as highly insoluble sulfide salts. Nickel was immobilized to 94 % in the digester and indicated the most dramatic effect on anaerobic digestion. At a concentration of 250 to 300 g Ni m-3 toxicity occurred. Lower nickel concentrations resulted in reversible process inhibition. Copper up to 1000 g Cu m-3 caused reversible inhibition of acid producing, fermentative, and methanogenic bacteria. The time necessary for recovery of the process was dependent on the initial copper concentration in the digester. The organisms indicated capability of adaptation to copper. The copper uptake in the digester was 97 %. Cadmium inhibited digestion of sewage sludge up to approximately 50 % at 650 g Cd m-3. For long durations of acclimation a tendency toward recovery was observed. The cadmium uptake in the digested sludge was 99 %. Chromium and lead were uptaken at 99.9 % during digestion. Hence, the addition of these metals up to 1000 mg Cr/l and 600 mg Pb/l showed only little effect on anaerobic digestion.
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Chauret, Christian, Susan Springthorpe, and Syed Sattar. "Fate ofCryptosporidiumoocysts,Giardiacysts, and microbial indicators during wastewater treatment and anaerobic sludge digestion." Canadian Journal of Microbiology 45, no. 3 (March 1, 1999): 257–62. http://dx.doi.org/10.1139/w99-001.
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The extent of reduction in selected microorganisms was tested during both aerobic wastewater treatment and anaerobic digestion of sludge at the wastewater treatment plant in Ottawa to compare the removal of two encysted pathogenic protozoa with that of microbial indicators. Samples collected included the raw wastewater, the primary effluent, the treated wastewater, the mixed sludge, the decanted liquor, and the cake. All of the raw sewage samples were positive for Cryptosporidium oocysts and Giardia cysts, as well as for the other microorganisms tested. During aerobic wastewater treatment (excluding the anaerobic sludge digestion), Cryptosporidium and Giardia were reduced by 2.96 log10and 1.40 log10, respectively. Clostridium perfringens spores, Clostridium perfringens total counts, somatic coliphages, and heterotrophic bacteria were reduced by approximately 0.89 log10, 0.96 log10, 1.58 log10, and 2.02 log10, respectively. All of the other microorganisms were reduced by at least 3.53 log10. Sludge samples from the plant were found to contain variable densities of microorganisms. Variability in microbial concentrations was sometimes great between samples, stressing the importance of collecting a large number of samples over a long period of time. In all cases, the bacterial concentrations in the cake (dewatered biosolids) samples were high even if reductions in numbers were observed with some bacteria. During anaerobic sludge digestion, no statistically significant reduction was observed for Clostridium perfringens, Enterococcus sp., Cryptosporidium oocysts, and Giardia cysts. A 1-2 log10reduction was observed with fecal coliforms and heterotrophic bacteria. However, the method utilized to detect the protozoan parasites does not differentiate between viable and nonviable organisms. On the other hand, total coliforms and somatic coliphages were reduced by 0.35 log10and 0.09 log10, respectively. These results demonstrate the relative persistence of the protozoa in sewage sludge during wastewater treatment.Key words: Cryptosporidium, Giardia, indicators, wastewater, sludge.
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Mason, C. A., A. Häner, and G. Hamer. "Aerobic Thermophilic Waste Sludge Treatment." Water Science and Technology 25, no. 1 (January 1, 1992): 113–18. http://dx.doi.org/10.2166/wst.1992.0017.
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The expansion in both industrial and municipal wastewater treatment in recent years has resulted in a major increase in the quantities of by-product sludge produced and has exacerbated problems of waste sludge treatment and/or disposal. The traditional method for waste sewage sludge treatment is anaerobic mesophilic digestion for sludges that are to be disposed of on agricultural land. Other disposal methods for untreated sludges include incineration, an option receiving increased interest, and ocean dumping, an option that is environmentally incompatable and used much less frequently today compared with 10 years ago. Sewage sludge can be considered to be a resource as far as its mineral nutrient composition is concerned. However, this resource cannot be exploited in agriculture because sludges are inevitably contaminated with noxious chemicals that partition into the sludge during either primary or secondary wastewater treatment. In the case sewage sludge, pathogenic and potentially pathogenic organisms are also present unless such contaminants are removed during treatment. Traditional mesophilic treatment under anaerobic conditions does not remove either noxious chemicals such as detergent residues or pathogenic organisms to a satisfactory degree. During the past decade, autothermal aerobic thermophilic pretreatment processes have been introduced as a complementary sludge treatment stage. Such aerobic pretreatment processes allow both the biodegradation of chemicals that are recalcitrant to anaerobic treatment and the thermal inactivation of pathogenic organisms. However, their introduction as a total treatment process for sludges is inhibited by their relatively poor conversion efficiencies as far as mineralization is concerned. In this contribution the biodegradation bacteria under aerobic thermophilic conditions will be described and discussed and concepts for biomass yield coefficient reduction that could enhance aerobic thermophilic sludge treatment process effectiveness will be introduced.
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Oszust, Karolina, and Magdalena Frąc. "Evaluation of microbial community composition of dairy sewage sludge, corn silage, grass straw, and fruit waste biomass for potential use in biogas production or soil enrichment." BioResources 13, no. 3 (June 11, 2018): 5740–64. http://dx.doi.org/10.15376/biores.13.3.5740-5764.
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The purpose of the study was to link microbial community composition and chemical properties of various biomass and their resulting digestate residues for their potential use in biogas production or soil enrichment. The order of biogas production, graded from high to low was as follows: corn silage, grass silage, fruit waste, and dairy sewage sludge. Different bacterial families were predominant in different biomass. Corn silage deteriorated as a result of long-term air exposition and may serve as an efficient feedstock substrate for anaerobic digestion. A positive role in plant biocontrol microorganisms found in grass straw residues, and reasonable biogas yield obtained from this substrate suggests the use of grass straw for biogas production and its residues to enrich the soil. Due to potential threat of introducing pathogens into the soil within fruit waste or dairy sewage sludge, or soil acidification by fruit waste repeated use in field application, this biomass should be sanitized prior to soil application. Simultaneously, low biogas yields from fruit waste and dairy sewage sludge substrates make it necessary to transform them in anaerobic digestion with more energetic co-substrates. Tested residues may deliver a robust and wide range of methanogens as inoculum for further anaerobic digestion process.
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Poszytek, Krzysztof, Joanna Karczewska-Golec, Anna Ciok, Przemyslaw Decewicz, Mikolaj Dziurzynski, Adrian Gorecki, Grazyna Jakusz, et al. "Genome-Guided Characterization of Ochrobactrum sp. POC9 Enhancing Sewage Sludge Utilization—Biotechnological Potential and Biosafety Considerations." International Journal of Environmental Research and Public Health 15, no. 7 (July 16, 2018): 1501. http://dx.doi.org/10.3390/ijerph15071501.
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Sewage sludge is an abundant source of microorganisms that are metabolically active against numerous contaminants, and thus possibly useful in environmental biotechnologies. However, amongst the sewage sludge isolates, pathogenic bacteria can potentially be found, and such isolates should therefore be carefully tested before their application. A novel bacterial strain, Ochrobactrum sp. POC9, was isolated from a sewage sludge sample collected from a wastewater treatment plant. The strain exhibited lipolytic, proteolytic, cellulolytic, and amylolytic activities, which supports its application in biodegradation of complex organic compounds. We demonstrated that bioaugmentation with this strain substantially improved the overall biogas production and methane content during anaerobic digestion of sewage sludge. The POC9 genome content analysis provided a deeper insight into the biotechnological potential of this bacterium and revealed that it is a metalotolerant and a biofilm-producing strain capable of utilizing various toxic compounds. The strain is resistant to rifampicin, chloramphenicol and β-lactams. The corresponding antibiotic resistance genes (including blaOCH and cmlA/floR) were identified in the POC9 genome. Nevertheless, as only few genes in the POC9 genome might be linked to pathogenicity, and none of those genes is a critical virulence factor found in severe pathogens, the strain appears safe for application in environmental biotechnologies.
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Zieliński, Marcin, Marcin Dębowski, and Joanna Kazimierowicz. "The Effect of Static Magnetic Field on Methanogenesis in the Anaerobic Digestion of Municipal Sewage Sludge." Energies 14, no. 3 (January 24, 2021): 590. http://dx.doi.org/10.3390/en14030590.
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The present study aimed to determine the effect of a 17.6 mT static magnetic field (SMF) on the efficiency of anaerobic digestion (AD) of municipal sewage sludge (MSS). The SMF had a significant impact on methane (CH4) production efficiency, the levels of fermentation rate (ηFMSS) vs. removal rate (ηVS), and the structure of the anaerobic bacteria consortium, but it did not affect cumulative biogas production. The highest CH4 yield (431 ± 22 dm3CH4/kgVS) and the highest methane content in the biogas (66.1% ± 1.9%) were found in the variant in which the SMF exposure time was 144 min/day. This variant also produced the highest ηFMSS and ηVS values, reaching 73.8% ± 2.3% and ηVS 36.9% ± 1.6%, respectively. Longer anaerobic sludge retention time in the SMF area significantly decreased AD efficiency and caused a significant reduction in the number of methanogens in the anaerobic bacteria community. The lowest values were observed for SMF exposure time of 432 min/day, which produced only 54.8 ± 1.9% CH4 in the biogas. A pronounced reduction was recorded in the Archaea (ARC915) and Methanosaeta (MX825) populations in the anaerobic sludge, i.e., to 20% ± 11% and 6% ± 2%, respectively.
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Mondal, Tania, Duncan A. Rouch, Nerida Thurbon, Stephen R. Smith, and Margaret A. Deighton. "Factors affecting decay of Salmonella Birkenhead and coliphage MS2 during mesophilic anaerobic digestion and air drying of sewage sludge." Journal of Water and Health 13, no. 2 (December 8, 2014): 459–72. http://dx.doi.org/10.2166/wh.2014.313.
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Factors affecting the decay of Salmonella Birkenhead and coliphage, as representatives of bacterial and viral pathogens, respectively, during mesophilic anaerobic digestion (MAD) and air drying treatment of anaerobically digested sewage sludge were investigated. Controlled concentrations of S. Birkenhead were inoculated into non-sterile, autoclaved, γ-irradiated and nutrient-supplemented sludge and cultures were incubated at 37 °C (MAD sludge treatment temperature) or 20 °C (summer air drying sludge treatment temperature). Nutrient limitation caused by microbial competition was the principal mechanism responsible for the decay of S. Birkenhead by MAD and during air drying of digested sludge. The effects of protease activity in sludge on MS2 coliphage decay in digested and air dried sludge were also investigated. MS2 coliphage showed a 3.0–3.5 log10 reduction during incubation with sludge-protease extracts at 37 °C for 25 h. Proteases produced by indigenous microbes in sludge potentially increase coliphage inactivation and may therefore have a significant role in the decay of enteric viruses in sewage sludge. The results help to explain the loss of viability of enteric bacteria and viral pathogens with treatment process time and contribute to fundamental understanding of the various biotic inactivation mechanisms operating in sludge treatment processes at mesophilic and ambient temperatures.
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Grűbel, Klaudiusz, Alicja Machnicka, and Stanisław Wacławek. "Impact of Alkalization of Surplus Activated Sludge on Biogas Production." Ecological Chemistry and Engineering S 20, no. 2 (June 1, 2013): 343–51. http://dx.doi.org/10.2478/eces-2013-0025.
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Abstract Large amounts of sludge are produced in biological wastewater treatment plants. Since the sludge is highly contaminated, it has to undergo proper stabilization before it is disposed or utilized in an environmentally safe way. On the whole, the aim of bacterial cell disintegration is the release of cell contents in the form of an aqueous extract. Chemical disintegration of surplus activated sludge by alkalization results in destruction and disruption of the flocs and microorganisms as well as increase concentration of organic matter in supernatant. The mesophilic anaerobic sewage sludge digestion is an established process, most often applied at medium and large municipal sewage treatment plants. Four major steps of anaerobic digestion are distinguished. The first hydrolysis step leads to solubilization of insoluble particulate matter and biological decomposition of organic polymers to monomers or dimers. The hydrolysis step is recognized as the rate-limiting step of the following second and third steps, the processes of acidogenesis and acetogenesis. Chemical disintegration activates biological hydrolysis and, therefore, it can significantly increase the stabilization rate of the secondary sludge. It has been shown that when the activated sludge was subjected to alkalization to pH 9.0 value, the COD concentration increased from 101 to 530 mg/dm3 in sludge supernatant. The paper presents a potential application of chemical disintegration for sewage sludge (mainly activated sludge) to upgrading biogas production.
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Alhraishawi, Ali, and Sukru Aslan. "Effect of Lipid Content on Anaerobic Digestion Process and Microbial Community: Review Study." European Scientific Journal, ESJ 8 (August 23, 2022): 197. http://dx.doi.org/10.19044/esj.2022.v8n0p197.
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The indiscriminate release of significant amounts of food waste, fat oil and grease, and sewage sludge (SS) into the environment causes severe contamination in many nations. There are numerous potential treatment methods to cope with the organic wastes, but anaerobic digestion is currently widely accepted to handle different kinds of biological waste. One of the pillars supporting anaerobic digester biogas production increase in treatment plants is the use of fats in the wastewaters. However, it has been claimed that high-fat wastes, particularly mono-digestion in the anaerobic reactor, inhibits acetoclastic and methanotrophic bacteria, delays the formation of gas even more, and overtaxes the system. This paper examines the research on the impact of lipids on biogas enhancement, reactor inhibition, impact on the microbial communities, and co-digestion with lipids in the anaerobic digestion process.
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Parravicini, V., K. Svardal, R. Hornek, and H. Kroiss. "Aeration of anaerobically digested sewage sludge for COD and nitrogen removal: optimization at large-scale." Water Science and Technology 57, no. 2 (January 1, 2008): 257–64. http://dx.doi.org/10.2166/wst.2008.020.
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The paper will report about the experiences at an Austrian large wastewater treatment plant of 720,000 population equivalents, where anaerobically digested sewage sludge is further stabilised under aerobic conditions. Enhanced stabilisation of the anaerobically digested sludge was required at the plant in order to get a permit for landfill disposal of the dewatered stabilized sludge. By implementing a post-aeration treatment (SRT ∼ 6d; 36 °C) after anaerobic digestion the organic content of the anaerobically well digested sludge can be decreased by 16%. Investigations on site showed that during digested sludge post-aeration anoxic phases for denitrification are needed to provide stable process conditions. In this way the pH value can be kept in a more favourable range for micro-organisms and concrete structures. Additionally, inhibition of the biological process due to nitrite accumulation can be avoided. By optimising the aeration/pause ratio ∼ 45% of total nitrogen in digested sludge can be removed. This significantly improves nitrogen removal efficiency at the wastewater treatment plant. NH4-removal occurs mainly through nitritation and denitritation with an efficiency of 98%. The costs/benefit analysis shows that post-aeration of digested sludge results in an increase of total annual costs for wastewater treatment of only 0.84%, corresponding to 0.19 Euro/pe/a. Result of molecular biological analyses (DGGE) indicate that all four ammonium-oxidizing bacteria species present in activated sludge can survive anaerobic digestion, but only two of them can adapt in the digested sludge post-aeration tanks. Additionally, in the post-aerated digested sludge a further ammonium-oxidizing bacteria species was identified.
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Modjinou, Mawufemo. "Re-engineering Domestic Septic Tanks into Biogas Tanks." Journal of Energy and Natural Resource Management 2, no. 2 (February 21, 2018): 54–62. http://dx.doi.org/10.26796/jenrm.v2i0.45.
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This study is to design a novel septic tank, named Anaerobic Upflow Domestic Septic Tank (AUDST) to recover biogas asenergy and treat domestic sewage. The green technology proposes alternate options to existing Domestic Septic Tanks (DST),encourages anaerobically pre-treatment to reduce bacteria, pollutants, Total Suspended Solids (TSS), Chemical oxygen demand(COD) and Biological oxygen demand (BOD) before the effluent is discharged or is removed by cesspit trucks. Studies haveshown that DST in homes partially treat or just store sewage. Again, these DST have to be emptied from time to time becauseit lack features that will sustain anaerobic activity and usually the sludge is disposed of directly into the sea, water bodies andeven into open places such as “Lavender Hills” without any treatment or disinfection. These practices cause severe public healthand environmental problems. To tackle the challenge at household level, DST are redesigned to treat domestic sewage with lessmanagement, low operating cost, low secondary discharge of pollutants. The proposed new design concept is operated throughthree (3) units: such as desilting, anaerobic digestion and facultative filtration units. The anaerobic digestion stage is made upof baffle and anaerobic filter for accommodating sludge and providing a more intimate contact between anaerobic biomass andsewage which improves treatment performance. The anaerobic unit is fitted with locally woven baskets prefilled with packingmaterials. The aim is to strengthen the biological treatment process at this stage. The Facultative Filtration unit of the model isalso packed with filtering media such as gravels (3-6mm in diameter) that is low in cost, and has a high durability to produceeffluent with lower pollutants and suspended solids content to meet Ghana’s Environmental Protection Agency (EPA) standardsfor the discharge of domestic effluents.
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L. Darkwah, M. Modjinou,. "Re-engineering Domestic Septic Tanks into Biogas Tanks." Journal of Energy and Natural Resource Management 2, no. 2 (February 21, 2018): 54–62. http://dx.doi.org/10.26796/jenrm.v2i2.45.
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This study is to design a novel septic tank, named Anaerobic Upflow Domestic Septic Tank (AUDST) to recover biogas asenergy and treat domestic sewage. The green technology proposes alternate options to existing Domestic Septic Tanks (DST),encourages anaerobically pre-treatment to reduce bacteria, pollutants, Total Suspended Solids (TSS), Chemical oxygen demand(COD) and Biological oxygen demand (BOD) before the effluent is discharged or is removed by cesspit trucks. Studies haveshown that DST in homes partially treat or just store sewage. Again, these DST have to be emptied from time to time becauseit lack features that will sustain anaerobic activity and usually the sludge is disposed of directly into the sea, water bodies andeven into open places such as “Lavender Hills” without any treatment or disinfection. These practices cause severe public healthand environmental problems. To tackle the challenge at household level, DST are redesigned to treat domestic sewage with lessmanagement, low operating cost, low secondary discharge of pollutants. The proposed new design concept is operated throughthree (3) units: such as desilting, anaerobic digestion and facultative filtration units. The anaerobic digestion stage is made upof baffle and anaerobic filter for accommodating sludge and providing a more intimate contact between anaerobic biomass andsewage which improves treatment performance. The anaerobic unit is fitted with locally woven baskets prefilled with packingmaterials. The aim is to strengthen the biological treatment process at this stage. The Facultative Filtration unit of the model isalso packed with filtering media such as gravels (3-6mm in diameter) that is low in cost, and has a high durability to produceeffluent with lower pollutants and suspended solids content to meet Ghana’s Environmental Protection Agency (EPA) standardsfor the discharge of domestic effluents.
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Cea-Barcia, Glenda, Hélène Carrère, Jean Philippe Steyer, and Dominique Patureau. "Evidence for PAH Removal Coupled to the First Steps of Anaerobic Digestion in Sewage Sludge." International Journal of Chemical Engineering 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/450542.
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Anaerobic degradation of polycyclic aromatic hydrocarbons has been brought to the fore, but information on removal kinetics and anaerobic degrading bacteria is still lacking. In order to explore the organic micropollutants removal kinetics under anaerobic conditions in regard to the methane production kinetics, the removal rate of 12 polycyclic aromatic hydrocarbons was measured in two anaerobic batch reactors series fed with a highly loaded secondary sludge as growth substrate. The results underscore that organic micropollutants removal is coupled to the initial stages of anaerobic digestion (acidogenesis and acetogenesis). In addition, the organic micropollutants kinetics suggest that the main removal mechanisms of these hydrophobic compounds are biodegradation and/or sequestration depending on the compounds.
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Arora, A., and S. Saxena. "Accumulation of Heavy Metals in Anaerobic Sludge and its Disposal by Landspreading." Advanced Materials Research 20-21 (July 2007): 213–16. http://dx.doi.org/10.4028/www.scientific.net/amr.20-21.213.
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Sludge, a natural, uncalled for byproduct of aerobic/ anaerobic biological digestion of organic matter present in wastewaters, also known as biosolids, is a thick, black and viscous substance comprising of dead and degraded microbial cells that digested the influents. This dead microbial material, accumulates on the bottom of anaerobic lagoons/ reactors, is organic in nature and rich in plant nutrients such as nitrogen, phosphorus and essential trace elements. It must be removed periodically. Therefore, the objective is to use the sludge as a fertilizer on agricultural land. It is an environmentally acceptable and economical method of sludge disposal. The application of organic wastes to farmland has increased over the years as it contributes to the preservation of the environment and results in an improvement of chemical, biochemical and physical properties of soil, although there is an increased risk of soil and ground water being contaminated by pollutants. Sewage sludge may contain heavy metals whose presence in soil may reduce enzyme activities and affect microbial communities in soil. They accumulate in soil and are taken up by crop plants thus posing health hazard. The study was conducted to characterize anaerobic sludge and quantify the concentration of heavy metals in it, to determine the suitability of the sludge as fertilizer for crops. Physicochemical and biochemical analyses showed that anaerobic sludge produced at Upflow Anaerobic Sludge Blanket (UASB) sewage treatment plant at Faridabad (an industrial town), Haryana, India, contained total organic C 15.714 percent, total Kjeldahl N 0.795 percent, available P 8 3g g-1and heavy metals Zn 1500 3g g-1, Ni 226 3g g-1, Fe 3000 3g g-1 and high activity of enzymes like alkaline phosphatase and dehydrogenase in the sludge. These enzymes are important for soil fertility and nutrient cycling. The toxic heavy metals have been accumulated by bacteria from sewage waters. The ideal C/N ratio, P and enzyme activities show its suitability as fertilizer but presence of heavy metals is a matter of concern. Therefore its application as crop fertilizer or onto land has to be carefully managed.
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Ciezkowska, Martyna, Tomasz Bajda, Przemyslaw Decewicz, Lukasz Dziewit, and Lukasz Drewniak. "Effect of Clinoptilolite and Halloysite Addition on Biogas Production and Microbial Community Structure during Anaerobic Digestion." Materials 13, no. 18 (September 17, 2020): 4127. http://dx.doi.org/10.3390/ma13184127.
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The study presents a comparison of the influence of a clinoptilolite-rich rock—zeolite (commonly used for improving anaerobic digestion processes)—and a highly porous clay mineral, halloysite (mainly used for gas purification), on the biogas production process. Batch experiments showed that the addition of each mineral increased the efficiency of mesophilic anaerobic digestion of both sewage sludge and maize silage. However, halloysite generated 15% higher biogas production during maize silage transformation. Halloysite also contributed to a much higher reduction of chemical oxygen demand for both substrates (by ~8% for maize silage and ~14% for sewage sludge) and a higher reduction of volatile solids and total ammonia for maize silage (by ~8% and ~4%, respectively). Metagenomic analysis of the microbial community structure showed that the addition of both mineral sorbents influenced the presence of key members of archaea and bacteria occurring in a well-operated biogas reactor. The significant difference between zeolite and halloysite is that the latter promoted the immobilization of key methanogenic archaea Methanolinea (belong to Methanomicrobia class). Based on this result, we postulate that halloysite could be useful not only as a sorbent for (bio)gas treatment methodologies but also as an agent for improving biogas production.
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Rodriguez-Perez, S., F. G. Fermoso, and C. Arnaiz. "Influence of different anoxic time exposures on active biomass, protozoa and filamentous bacteria in activated sludge." Water Science and Technology 74, no. 3 (May 23, 2016): 595–605. http://dx.doi.org/10.2166/wst.2016.247.
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Medium-sized wastewater treatment plants are considered too small to implement anaerobic digestion technologies and too large for extensive treatments. A promising option as a sewage sludge reduction method is the inclusion of anoxic time exposures. In the present study, three different anoxic time exposures of 12, 6 and 4 hours have been studied to reduce sewage sludge production. The best anoxic time exposure was observed under anoxic/oxic cycles of 6 hours, which reduced 29.63% of the biomass production compared with the oxic control conditions. The sludge under different anoxic time exposures, even with a lower active biomass concentration than the oxic control conditions, showed a much higher metabolic activity than the oxic control conditions. Microbiological results suggested that both protozoa density and abundance of filamentous bacteria decrease under anoxic time exposures compared to oxic control conditions. The anoxic time exposures 6/6 showed the highest reduction in both protozoa density, 37.5%, and abundance of filamentous bacteria, 41.1%, in comparison to the oxic control conditions. The groups of crawling ciliates, carnivorous ciliates and filamentous bacteria were highly influenced by the anoxic time exposures. Protozoa density and abundance of filamentous bacteria have been shown as promising bioindicators of biomass production reduction.
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Kazimierowicz, Joanna, Marcin Dębowski, and Marcin Zieliński. "Effect of Pharmaceutical Sludge Pre-Treatment with Fenton/Fenton-like Reagents on Toxicity and Anaerobic Digestion Efficiency." International Journal of Environmental Research and Public Health 20, no. 1 (December 24, 2022): 271. http://dx.doi.org/10.3390/ijerph20010271.
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Sewage sludge is successfully used in anaerobic digestion (AD). Although AD is a well-known, universal and widely recognized technology, there are factors that limit its widespread use, such as the presence of substances that are resistant to biodegradation, inhibit the fermentation process or are toxic to anaerobic microorganisms. Sewage sludge generated by the pharmaceutical sector is one such substance. Pharmaceutical sewage sludge (PSS) is characterized by high concentrations of biocides, including antibiotics and other compounds that have a negative effect on the anaerobic environment. The aim of the present research was to determine the feasibility of applying Advanced Oxidation Processes (AOP) harnessing Fenton’s (Fe2+/H2O2) and Fenton-like (Fe3+/H2O2) reaction to PSS pre-treatment prior to AD. The method was analyzed in terms of its impact on limiting PSS toxicity and improving methane fermentation. The use of AOP led to a significant reduction of PSS toxicity from 53.3 ± 5.1% to 35.7 ± 3.2%, which had a direct impact on the taxonomic structure of anaerobic bacteria, and thus influenced biogas production efficiency and methane content. Correlations were found between PSS toxicity and the presence of Archaea and biogas yields in the Fe2+/H2O2 group. CH4 production ranged from 363.2 ± 11.9 cm3 CH4/g VS in the control PSS to approximately 450 cm3/g VS. This was 445.7 ± 21.6 cm3 CH4/g VS (1.5 g Fe2+/dm3 and 6.0 g H2O2/dm3) and 453.6 ± 22.4 cm3 CH4/g VS (2.0 g Fe2+/dm3 and 8.0 g H2O2/dm3). The differences between these variants were not statistically significant. Therefore, due to the economical use of chemical reagents, the optimal tested dose was 1.5 g Fe2+/6.0 g H2O2. The use of a Fenton-like reagent (Fe3+/H2O2) resulted in lower AD efficiency (max. 393.7 ± 12.1 cm3 CH4/g VS), and no strong linear relationships between the analyzed variables were found. It is, therefore, a more difficult method to estimate the final effects. Research has proven that AOP can be used to improve the efficiency of AD of PSS.
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Poszytek, Karczewska-Golec, Dziurzynski, Stepkowska-Kowalska, Gorecki, Decewicz, Dziewit, and Drewniak. "Genome-Wide and Functional View of Proteolytic and Lipolytic Bacteria for Efficient Biogas Production through Enhanced Sewage Sludge Hydrolysis." Molecules 24, no. 14 (July 18, 2019): 2624. http://dx.doi.org/10.3390/molecules24142624.
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In this study, we used a multifaceted approach to select robust bioaugmentation candidates for enhancing biogas production and to demonstrate the usefulness of a genome-centric approach for strain selection for specific bioaugmentation purposes. We also investigated the influence of the isolation source of bacterial strains on their metabolic potential and their efficiency in enhancing anaerobic digestion. Whole genome sequencing, metabolic pathway reconstruction, and physiological analyses, including phenomics, of phylogenetically diverse strains, Rummeliibacillus sp. POC4, Ochrobactrum sp. POC9 (both isolated from sewage sludge) and Brevundimonas sp. LPMIX5 (isolated from an agricultural biogas plant) showed their diverse enzymatic activities, metabolic versatility and ability to survive under varied growth conditions. All tested strains display proteolytic, lipolytic, cellulolytic, amylolytic, and xylanolytic activities and are able to utilize a wide array of single carbon and energy sources, as well as more complex industrial by-products, such as dairy waste and molasses. The specific enzymatic activity expressed by the three strains studied was related to the type of substrate present in the original isolation source. Bioaugmentation with sewage sludge isolates–POC4 and POC9–was more effective for enhancing biogas production from sewage sludge (22% and 28%, respectively) than an approach based on LPMIX5 strain (biogas production boosted by 7%) that had been isolated from an agricultural biogas plant, where other type of substrate is used.
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Worwąg, Małgorzata. "Impact of Adding Biopreparations on the Anaerobic Co-Digestion of Sewage Sludge with Grease Trap Waste." Civil And Environmental Engineering Reports 22, no. 3 (September 1, 2016): 167–79. http://dx.doi.org/10.1515/ceer-2016-0045.
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Abstract The aim of the study was to evaluate the effect of using biopreparations on efficiency of the co-fermentation process. Commercial bacterial biopreparations DBC Plus Type L, DBC Plus Type R5 and yeast biopreparations were used in the study. The process of cofermentation of sewage sludge with grease trap waste from a production plant that manufactured methyl esters of fatty acids was analysed in the laboratory environment under mesophilic conditions. The sludge in the reactor was replaced once a day, with hydraulic retention time of 10 days. Grease trap waste accounted for 35%wt. of the fermentation mixture. The stabilization process was monitored everyday based on the measurements of biogas volume. Addition of yeast biopreparation to methane fermentation of sewage sludge with grease trap waste caused an increase in mean daily biogas production from 6.9 dm3 (control mixture) to 9.21dm3 (mixture M3). No differences in biogas production were found for other cases (mixtures M1, M2). A similar relationship was observed for methane content in biogas.
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Fujishima, S., T. Miyahara, and T. Noike. "Effect of moisture content on anaerobic digestion of dewatered sludge: ammonia inhibition to carbohydrate removal and methane production." Water Science and Technology 41, no. 3 (February 1, 2000): 119–27. http://dx.doi.org/10.2166/wst.2000.0063.
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The purpose of this study is to investigate the effect of moisture content on anaerobic digestion of dewatered sewage sludge under mesophilic condition. The moisture contents of sludge fed to reactors were 97.0%, 94.6%, 92.9%, 91.1% and 89.0%. The VS removal efficiency changed from 45.6% to 33.8%, as the moisture content of sludge fed to digester decreased from 97.0% to 89.0%. The carbohydrate removal efficiency also decreased from 71.1% to 27.8%. Methane production decreased when the moisture content of sludge was lower than 91.1%. The number of glucose consuming acidogenic bacteria was decreased from 3.1×106 to 3.1×108(MPN/mL) as the moisture content decreased from 91.1% to 89.0%. The numbers of hydrogenotrophic and acetoclastic methanogenic bacteria decreased by one order of magnitude when the moisture content was lower than 91.1%. The decrease in numbers of glucose consuming acidogenic bacteria and methanogenic bacteria was found to correspond to the decrease in the carbohydrate removal efficiency and the accumulation of propionic acid. Batch experiments showed that acetoclastic methanogenic bacteria were acclimated to high ammonia concentration, on the other hand, glucose consuming acidogenic bacteria were inhibited.
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Mudzanani, Khuthadzo, Esta van Heerden, Ryneth Mbhele, and Michael O. Daramola. "Enhancement of Biogas Production via Co-Digestion of Wastewater Treatment Sewage Sludge and Brewery Spent Grain: Physicochemical Characterization and Microbial Community." Sustainability 13, no. 15 (July 23, 2021): 8225. http://dx.doi.org/10.3390/su13158225.
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The present study intends to evaluate a synergy towards enhanced biogas production by co-digesting municipal sewage sludge (SS) with brewery spent grain (BSG). To execute this, physicochemical and metagenomics analysis was conducted on the sewage sludge substrate. The automatic methane potential test system II (AMPTS II) biochemical methane potential (BMP) batch setup was operated at 35 ± 5 °C, pH range of 6.5–7.5 for 30 days’ digestion time on AMPTS II and 150 days on semi-continuous setup, where the organic loading rate (OLR) was guided by pH and the volatile fatty acids to total alkalinity (VFA/TA) ratio. Metagenomics analysis revealed that Proteobacteria was the most abundant phyla, consisting of hydrolytic and fermentative bacteria. The archaea community of hydrogenotrophic methanogen genus was enriched by methanogens. The highest BMP was obtained with co-digestion of SS and BSG, and 9.65 g/kg of VS. This not only increased biogas production by 104% but also accelerated the biodegradation of organic matters. However, a significant reduction in the biogas yield, from 10.23 NL/day to 2.02 NL/day, was observed in a semi-continuous process. As such, it can be concluded that different species in different types of sludge can synergistically enhance the production of biogas. However, the operating conditions should be optimized and monitored at all times. The anaerobic co-digestion of SS and BSG might be considered as a cost-effective solution that could contribute to the energy self-efficiency of wastewater treatment works (WWTWs) and sustainable waste management. It is recommended to upscale co-digestion of the feed for the pilot biogas plant. This will also go a long way in curtailing and minimizing the impacts of sludge disposal in the environment.
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Orellana, Esteban, Carol Davies-Sala, Leandro D. Guerrero, Ignacio Vardé, Melisa Altina, María Cielo Lorenzo, Eva L. Figuerola, Rodrigo M. Pontiggia, and Leonardo Erijman. "Microbiome network analysis of co-occurrence patterns in anaerobic co-digestion of sewage sludge and food waste." Water Science and Technology 79, no. 10 (May 15, 2019): 1956–65. http://dx.doi.org/10.2166/wst.2019.194.
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Abstract Addition of food waste (FW) as a co-substrate in anaerobic digesters of wastewater treatment plants is a desirable strategy towards achievement of the potential of wastewater treatment plants to become energy-neutral, diverting at the same time organic waste from landfills. Because substrate type is a driver of variations in phylogenetic structure of digester microbiomes, it is critical to understand how microbial communities respond to changes in substrate composition and concentration. In this work, high throughput sequencing was used to monitor the dynamics of microbiome changes in four parallel laboratory-scale anaerobic digesters treating sewage sludge during acclimation to an increasing amount of food waste. A co-occurrence network was constructed using data from 49 metagenomes sampled over the 161 days of the digesters' operation. More than half of the nodes in the network were clustered in two major modules, i.e. groups of highly interconnected taxa that had much fewer connections with taxa outside the group. The dynamics of co-occurrence networks evidenced shifts that occurred within microbial communities due to the addition of food waste in the co-digestion process. A diverse and reproducible group of hydrolytic and fermentative bacteria, syntrophic bacteria and methanogenic archaea appeared to grow in a concerted fashion to allow stable performance of anaerobic co-digestion at high FW.
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Tonanzi, Barbara, Simona Crognale, Andrea Gianico, Stefano Della Sala, Paola Miana, Maria Chiara Zaccone, and Simona Rossetti. "Microbial Community Successional Changes in a Full-Scale Mesophilic Anaerobic Digester from the Start-Up to the Steady-State Conditions." Microorganisms 9, no. 12 (December 13, 2021): 2581. http://dx.doi.org/10.3390/microorganisms9122581.
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Anaerobic digestion is a widely used technology for sewage sludge stabilization and biogas production. Although the structure and composition of the microbial communities responsible for the process in full-scale anaerobic digesters have been investigated, little is known about the microbial successional dynamics during the start-up phase and the response to variations occurring in such systems under real operating conditions. In this study, bacterial and archaeal population dynamics of a full-scale mesophilic digester treating activated sludge were investigated for the first time from the start-up, performed without adding external inoculum, to steady-state operation. High-throughput 16S rRNA gene sequencing was used to describe the microbiome evolution. The large majority of the reads were affiliated to fermentative bacteria. Bacteroidetes increased over time, reaching 22% of the total sequences. Furthermore, Methanosaeta represented the most abundant methanogenic component. The specific quantitative data generated by real-time PCR indicated an enrichment of bacteria and methanogens once the steady state was reached. The analysis allowed evaluation of the microbial components more susceptible to the shift from aerobic to anaerobic conditions and estimation of the microbial components growing or declining in the system. Additionally, activated sludge was investigated to evaluate the microbial core selected by the WWTP operative conditions.
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Michalke, K., E. B. Wickenheiser, M. Mehring, A. V. Hirner, and R. Hensel. "Production of Volatile Derivatives of Metal(loid)s by Microflora Involved in Anaerobic Digestion of Sewage Sludge." Applied and Environmental Microbiology 66, no. 7 (July 1, 2000): 2791–96. http://dx.doi.org/10.1128/aem.66.7.2791-2796.2000.
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ABSTRACT Gases released from anaerobic wastewater treatment facilities contain considerable amounts of volatile methyl and hydride derivatives of metals and metalloids, such as arsine (AsH3), monomethylarsine, dimethylarsine, trimethylarsine, trimethylbismuth (TMBi), elemental mercury (Hg0), trimethylstibine, dimethyltellurium, and tetramethyltin. Most of these compounds could be shown to be produced by pure cultures of microorganisms which are representatives of the anaerobic sewage sludge microflora, i.e., methanogenic archaea (Methanobacterium formicicum,Methanosarcina barkeri, Methanobacterium thermoautotrophicum), sulfate-reducing bacteria (Desulfovibrio vulgaris, D. gigas), and a peptolytic bacterium (Clostridium collagenovorans). Additionally, dimethylselenium and dimethyldiselenium could be detected in the headspace of most of the pure cultures. This is the first report of the production of TMBi, stibine, monomethylstibine, and dimethylstibine by a pure culture of M. formicicum.
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Stiborova, Hana, Jan Wolfram, Katerina Demnerova, Tomas Macek, and Ondrej Uhlik. "Bacterial community structure in treated sewage sludge with mesophilic and thermophilic anaerobic digestion." Folia Microbiologica 60, no. 6 (April 30, 2015): 531–39. http://dx.doi.org/10.1007/s12223-015-0396-9.
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Morita, H., and H. Tsuboi. "Basic investigation on the chemical forms of heavy metals in a sewage treatment plant." Water Science and Technology 42, no. 9 (November 1, 2000): 159–65. http://dx.doi.org/10.2166/wst.2000.0195.
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Sewage sludge mainly consists of organic matter, and it is rich in nutrients. Therefore, sewage sludge is beneficial as an energy resource and as a raw material for fertilizer. However, heavy metals in it are the obstacle to utilization of sludge. This study was conducted in order to know the chemical forms of heavy metals and their behavior in a sewage treatment plant as a basic study for development of technology to reduce heavy metals in sludge. Chemical methods and biological methods, such as extraction using acid, bacteria leaching, are applied to reduce heavy metals. In using these methods, the efficiency depends on the chemical forms of heavy metals. From this point of view, factors, which affect the chemical forms of heavy metals, were investigated through the survey at some plants of different conditions. Besides, experiments on the anaerobic digestion process, in which the chemical forms of heavy metals were expected to change, were conducted. As the results of these studies, it was found that the chemical forms of heavy metals and their behavior vary according to the species of heavy metals. In comparison of zinc (Zn), copper (Cu) and nickel (Ni), Cu was found to be changed most easily into a stable chemical form such as carbonate and sulfide. Zn was the second to Cu in its tendency to be stabilized. As for Ni, the tendency was further less than Zn.
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Carrington, E. G., E. B. Pike, D. Auty, and R. Morris. "Destruction of Faecal Bacteria, Enteroviruses and OVA of Parasites in Wastewater Sludge by Aerobic Thermophilic and Anaerobic Mesophilic Digestion." Water Science and Technology 24, no. 2 (July 1, 1991): 377–80. http://dx.doi.org/10.2166/wst.1991.0094.
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A new sludge treatment plant at Harrogate South Sewage Treatment Works is designed to handle up to 4 tonnes (dry solids) daily. Sludge is thickened continuously up to 8% (ds) and is then treated in parallel anaerobic mesophilic (AD) and thermophilic aerobic digestion (TAD) plants each with a maximum working volume of 530m3. Microbiological studies were carried out to compare the destruction of pathogens and faecal indicator bacteria. The AD plant operated with a mean retention of 26 days at 34 °C and achieved 49% reduction of volatile solids. The TAD plant operated with a mean retention of 28 days at 55 °C and reduced volatile solids by 35%. Operation was on a pump in-pump out cycle, guaranteeing 4h retention for all sludge. The disinfecting ability of TAD exceeded that of AD since it reduced counts of Enterobacteriaceae, thermotolerant coliforms and faecal streptococci to below 103/100ml, rendered cytopathic enteroviruses undetectable and destroyed viability of Ascaris suum ova within 4h. The AD process reduced bacterial counts by 90% and enteroviruses by 99%, but has no effect upon viability of Ascaris ova.
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Redhead, Sky, Jeroen Nieuwland, Sandra Esteves, Do-Hoon Lee, Dae-Wi Kim, Jordan Mathias, Chang-Jun Cha, et al. "Fate of antibiotic resistant E. coli and antibiotic resistance genes during full scale conventional and advanced anaerobic digestion of sewage sludge." PLOS ONE 15, no. 12 (December 1, 2020): e0237283. http://dx.doi.org/10.1371/journal.pone.0237283.
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Antibiotic resistant bacteria (ARB) and their genes (ARGs) have become recognised as significant emerging environmental pollutants. ARB and ARGs in sewage sludge can be transmitted back to humans via the food chain when sludge is recycled to agricultural land, making sludge treatment key to control the release of ARB and ARGs to the environment. This study investigated the fate of antibiotic resistant Escherichia coli and a large set of antibiotic resistance genes (ARGs) during full scale anaerobic digestion (AD) of sewage sludge at two U.K. wastewater treatment plants and evaluated the impact of thermal hydrolysis (TH) pre-treatment on their abundance and diversity. Absolute abundance of 13 ARGs and the Class I integron gene intI1 was calculated using single gene quantitative (q) PCR. High through-put qPCR analysis was also used to determine the relative abundance of 370 ARGs and mobile genetic elements (MGEs). Results revealed that TH reduced the absolute abundance of all ARGs tested and intI1 by 10–12,000 fold. After subsequent AD, a rebound effect was seen in many ARGs. The fate of ARGs during AD without pre-treatment was variable. Relative abundance of most ARGs and MGEs decreased or fluctuated, with the exception of macrolide resistance genes, which were enriched at both plants, and tetracyline and glycopeptide resistance genes which were enriched in the plant employing TH. Diversity of ARGs and MGEs decreased in both plants during sludge treatment. Principal coordinates analysis revealed that ARGs are clearly distinguished according to treatment step, whereas MGEs in digested sludge cluster according to site. This study provides a comprehensive within-digestor analysis of the fate of ARGs, MGEs and antibiotic resistant E. coli and highlights the effectiveness of AD, particularly when TH is used as a pre-treatment, at reducing the abundance of most ARGs and MGEs in sludgeand preventing their release into the environment.
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Świątczak, Piotr, Agnieszka Cydzik-Kwiatkowska, and Paulina Rusanowska. "Microbiota of anaerobic digesters in a full-scale wastewater treatment plant." Archives of Environmental Protection 43, no. 3 (September 1, 2017): 53–60. http://dx.doi.org/10.1515/aep-2017-0033.
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AbstractAnaerobic digestion is an important technology for the bio-based economy. The stability of the process is crucial for its successful implementation and depends on the structure and functional stability of the microbial community. In this study, the total microbial community was analyzed during mesophilic fermentation of sewage sludge in full-scale digesters.The digesters operated at 34–35°C, and a mixture of primary and excess sludge at a ratio of 2:1 was added to the digesters at 550 m3/d, for a sludge load of 0.054 m3/(m3·d). The amount and composition of biogas were determined. The microbial structure of the biomass from the digesters was investigated with use of next-generation sequencing.The percentage of methanogens in the biomass reached 21%, resulting in high quality biogas (over 61% methane content). The abundance of syntrophic bacteria was 4.47%, and stable methane production occurred at a Methanomicrobia to Synergistia ratio of 4.6:1.0. The two most numerous genera of methanogens (about 11% total) wereMethanosaetaandMethanolinea, indicating that, at the low substrate loading in the digester, the acetoclastic and hydrogenotrophic paths of methane production were equally important. The high abundance of the orderBacteroidetes, including the classCytophagia(11.6% of all sequences), indicated the high potential of the biomass for efficient degradation of lignocellulitic substances, and for degradation of protein and amino acids to acetate and ammonia.This study sheds light on the ecology of microbial groups that are involved in mesophilic fermentation in mature, stably-performing microbiota in full-scale reactors fed with sewage sludge under low substrate loading.
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Trably, E., D. Patureau, and J. P. Delgenes. "Enhancement of polycyclic aromatic hydrocarbons removal during anaerobic treatment of urban sludge." Water Science and Technology 48, no. 4 (August 1, 2003): 53–60. http://dx.doi.org/10.2166/wst.2003.0220.
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Anaerobically stabilized sewage sludge has potential to partially substitute synthetic fertilizers. The main risk with the recycling of urban sludge on agricultural soils is the accumulation of unwanted products, such as trace metals and organic micropollutants. In this context, the polycyclic aromatic hydrocarbons (PAHs) are particularly monitored because of their toxic properties at low concentrations and their high resistance to biological degradation. The aim of the present study was to optimize PAHs removal during anaerobic digestion of contaminated sewage sludge. Thirteen PAHs were monitored in laboratory-scale anaerobic bioreactors under mesophilic (35°C) and thermophilic (55°C) methanogenic conditions. Abiotic losses were statistically significant for the lightest PAHs, such as fluorene, phenanthrene and anthracene. It was shown that PAH removal was due to a specific biological activity. Biological PAHs removal was significantly enhanced by an increase of the temperature from 35°C to 55°C, especially for the heaviest PAHs. Bioaugmentation experiment was also performed by addition of a PAH-adapted bacterial consortium to a non-acclimated reactor. Significant enhancement of PAHs removal was observed. It was finally shown that PAH removal efficiencies and methanogenic performances were closely linked. The rate of biogas production may be used as an indicator of bacterial activity on PAH removal.
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Esposito, G., L. Frunzo, A. Panico, and G. d'Antonio. "Mathematical modelling of disintegration-limited co-digestion of OFMSW and sewage sludge." Water Science and Technology 58, no. 7 (October 1, 2008): 1513–19. http://dx.doi.org/10.2166/wst.2008.509.
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This paper presents a mathematical model able to simulate under dynamic conditions the physical, chemical and biological processes prevailing in a OFMSW and sewage sludge anaerobic digestion system. The model proposed is based on differential mass balance equations for substrates, products and bacterial groups involved in the co-digestion process and includes the biochemical reactions of the substrate conversion and the kinetics of microbial growth and decay. The main peculiarity of the model is the surface based kinetic description of the OFMSW disintegration process, whereas the pH determination is based on a nine-order polynomial equation derived by acid-base equilibria. The model can be applied to simulate the co-digestion process for several purposes, such as the evaluation of the optimal process conditions in terms of OFMSW/sewage sludge ratio, temperature, OFMSW particle size, solid mixture retention time, reactor stirring rate, etc. Biogas production and composition can also be evaluated to estimate the potential energy production under different process conditions. In particular, model simulations reported in this paper show the model capability to predict the OFMSW amount which can be treated in the digester of an existing MWWTP and to assess the OFMSW particle size diminution pre-treatment required to increase the rate of the disintegration process, which otherwise can highly limit the co-digestion system.
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Kwon, Kiwook, Hyosun Kim, Woojin Kim, and Junbae Lee. "Efficient Nitrogen Removal of Reject Water Generated from Anaerobic Digester Treating Sewage Sludge and Livestock Manure by Combining Anammox and Autotrophic Sulfur Denitrification Processes." Water 11, no. 2 (January 24, 2019): 204. http://dx.doi.org/10.3390/w11020204.
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The reject water from anaerobic digestion with high (Total Nitrogen) TN concentration was treated by a demonstration plant combining the anammox process and SOD (SOD®; Sulfur Oxidation Denitrification) process. The anaerobic digestion was a co-digestion of livestock wastewater, food waste water, and sewage sludge so that the TN concentration and conductivity of the reject water were very high. This anammox plant was the first anammox demonstration plant in South Korea. The maximum TN removal efficiency of 80% was achieved for the anammox reactor under nitrogen loading rate (NLR) of 0.45 kg-N/m3·d. As a result of decreasing the dilution of the reject water, the influent conductivity and NLR values were increased to 7.8 mS/cm and 0.7 kg/m3·d, causing a rapid decrease in the TN removal efficiency. The sludge concentration from the hydro-cyclone overflow was about 40 mg-MLVSS/L in which small sized anammox granules were detected. It was proven that the increase in (Mixed Liquor Volatile Suspended Solids) MLVSS concentration in the anammox reactor was not easy under high influent conductivity and NLR. 97% of NO2−-N+NO3−-N generated from the anammox process could be treated successfully by the SOD reactor. A TN removal efficiency of 35% under poor annamox treatment could increase to 67% by applying the SOD reactor post treatment for the removal of NO3−-N. The dominant anammox bacteria in the anammox reactor was identified as Brocadia fulgida and 9.3% (genus level) of the bacteria out of the total bacteria were anammox bacteria.
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Gnanambal, Venkatachalam Sundaresan, and Krishnaswamy Swaminathan. "Biogas production from renewable lignocellulosic biomass." International Journal of Environment 4, no. 2 (June 3, 2015): 341–47. http://dx.doi.org/10.3126/ije.v4i2.12662.
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Effect of raw and biologically treated lignocellulosic biomass using cow dung slurry for biogas production is reported. Biomass is an energy source. Water containing biomass such as sewage sludge, cow dung slurry and lignocellulosic waste, has several important advantages and one of the key feature is renewability. Cow dung slurry has the potential to produce large amounts of biogas. Four categories of bacteria viz., hydrolytic, fermentative, fermentative acidogenic and acidogenic-methanogenic bacteria are involved in the production of biogas. The different characteristics of the cow dung slurry were determined according to standard methods. Hemicellulose, cellulose and lignin content of the lignocellulosic waste were also determined in our earlier studies. The substrates were digested under anaerobic condition for 5 days. The total biogas and methane produced during anaerobic digestion were estimated on 5th day. The total biogas produced during digestion was estimated by water displacement method. Biological methane production was estimated by using Saccharometer. DOI: http://dx.doi.org/10.3126/ije.v4i2.12662 International Journal of Environment Vol.4(2) 2015: 341-347
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Caffaz, S., R. Canziani, C. Lubello, and D. Santianni. "Upgrading of Florence wastewater treatment plant: co-digestion and nitrogen autotrophic removal." Water Science and Technology 52, no. 4 (August 1, 2005): 9–17. http://dx.doi.org/10.2166/wst.2005.0082.
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In recent years a completely autotrophic nitrogen removal process based on Anammox biomass has been tested in a few European countries in order to treat anaerobic supernatant and to increase the COD/N ratio in municipal wastewater. This work reports experimental results on a possible technical solution to upgrade the S. Colombano treatment plant which treats wastewater from the Florentine urban area. The idea is to use 50% of the volume of the anaerobic digester in order to treat external sewage sludge (as septic tank sludge) together with waste activated sludge and to treat the resulting effluent on a SHARON-ANAMMOX process in order to remove nitrogen from the anaerobic supernatant. Anaerobic co-digestion, tested in a 200 L pilot plant, enables low cost treatment of septic tank sludge and increases biogas production; however, it also increases the nitrogen load re-circulated to the WWTP, where nitrogen removal efficiency is already low (<50%), due to the low COD/N ratio, which limits predenitrification efficiency. Experimental results from a SHARON process tested in a lab-scale pilot plant show that nitrite oxidising bacteria are washed-out and steady nitrite production can be achieved at retention times in the range 1–1.5 days, at 35 °C. In a lab-scale SBR reactor, coupled with a nitration bioreactor, maximum specific nitrogen removal rate under nitrite-limiting conditions (with doubling time equal to about 26 days at 35 °C) was equal to 0.22 kgN/kgSSV/d, about 44 times the rate measured in inoculum Anammox sludge. Finally, a cost analysis of the proposed upgrade is reported.
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El Houari, Abdelaziz, Magali Ranchou-Peyruse, Anthony Ranchou-Peyruse, Rhizlane Bennisse, Radia Bouterfas, Maria Soledad Goni Urriza, Abdel-Ilah Qatibi, and Rémy Guyoneaud. "Microbial Communities and Sulfate-Reducing Microorganisms Abundance and Diversity in Municipal Anaerobic Sewage Sludge Digesters from a Wastewater Treatment Plant (Marrakech, Morocco)." Processes 8, no. 10 (October 14, 2020): 1284. http://dx.doi.org/10.3390/pr8101284.
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Both molecular analyses and culture-dependent isolation were combined to investigate the diversity of sulfate-reducing prokaryotes and explore their role in sulfides production in full-scale anaerobic digesters (Marrakech, Morocco). At global scale, using 16S rRNA gene sequencing, Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria, Synergistetes, and Euryarchaeota were the most dominant phyla. The abundance of Archaea (3.1–5.7%) was linked with temperature. The mcrA gene ranged from 2.18 × 105 to 1.47 × 107 gene copies.g−1 of sludge. The sulfate-reducing prokaryotes, representing 5% of total sequences, involved in sulfides production were Peptococcaceae, Syntrophaceae, Desulfobulbaceae, Desulfovibrionaceae, Syntrophobacteraceae, Desulfurellaceae, and Desulfobacteraceae. Furthermore, dsrB gene ranged from 2.18 × 105 to 1.92 × 107 gene copies.g−1 of sludge. The results revealed that exploration of diversity and function of sulfate-reducing bacteria may play a key role in decreasing sulfide production, an undesirable by-product, during anaerobic digestion.
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Tong, Juan, Jibao Liu, Xiang Zheng, Junya Zhang, Xiaotang Ni, Meixue Chen, and Yuansong Wei. "Fate of antibiotic resistance bacteria and genes during enhanced anaerobic digestion of sewage sludge by microwave pretreatment." Bioresource Technology 217 (October 2016): 37–43. http://dx.doi.org/10.1016/j.biortech.2016.02.130.
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Zhou, Ying, Shuohui Shi, Jiong Zhou, Lei He, Xuejie He, Yang Lu, Qiang He, and Jian Zhou. "Composition Characterization and Transformation Mechanism of Dissolved Organic Matters in a Full-Scale Membrane Bioreactor Treating Co-Digestion Wastewater of Food Waste and Sewage Sludge." Sustainability 14, no. 11 (May 27, 2022): 6556. http://dx.doi.org/10.3390/su14116556.
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The membrane bioreactor (MBR) serves as the most widely used technology in anaerobic digestion wastewater treatment, but the composition and transformation of the dissolved organic matters (DOMs) are vague. This study focused on the composition characterization and transformation mechanism of DOMs in real co-digestion wastewater of food waste and sewage sludge from a full-scale MBR via molecular weight cut-off, 3D-EEM, FT-IR, and SPME-GC/MS. The results indicated that the co-digestion wastewater mainly comprised organics with molecular weight (MW) lower than 1 kDa and dominated by tryptophane-protein-like substances. The hydrolytic/acidogenic process improved the biodegradability with the conversion of high-MW organics into low-MW organics, while the two-stage A/O process possessed the highest contribution to the organic removal with the consumption of most DOMs. However, the deficient removal of refractory organics (MW < 5 kDa) in the ultrafiltration unit led to the residual DOMs in the effluent. The potential functional bacteria in the biological processes have also been identified and were principally affiliated with Proteobacteria and Firmicutes. These findings could help to advance the understanding of the co-digestion wastewater and provide fundamental information for the optimization and development of MBR in anaerobic digestion wastewater treatment.
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Yang, Xue, Xiang Liu, Si Chen, Guangmin Liu, Shuyan Wu, and Chunli Wan. "Volatile Fatty Acids Production from Codigestion of Food Waste and Sewage Sludge Based on β-Cyclodextrins and Alkaline Treatments." Archaea 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/1698163.
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Volatile fatty acids (VFAs) are preferred valuable resources, which can be produced from anaerobic digestion process. This study presents a novel technology using β-cyclodextrins (β-CD) pretreatment integrated alkaline method to enhance VFAs production from codigestion of food waste and sewage sludge. Experiment results showed that optimized ratio of food waste to sewage sludge was 3 : 2 because it provided adequate organic substance and seed microorganisms. Based on this optimized ratio, the integrated treatment of alkaline pH 10 and β-CD addition (0.2 g/g TS) performed the best enhancement on VFAs production, and the maximum VFAs production was 8631.7 mg/L which was 6.13, 1.38, and 1.57 times higher than that of control, initial pH 10, and 0.2 g β-CD/g TS treatment, respectively. Furthermore, the hydrolysis rate of protein and polysaccharides was greatly improved in integration treatment, which was 1.18–3.45 times higher than that of other tests. Though the VFAs production and hydrolysis of polymeric organics were highly enhanced, the primary bacterial communities with different treatments did not show substantial differences.
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Sposob, Michal, Hee-Sung Moon, Dongjin Lee, and Yeo-Myeong Yun. "Microbiome of Seven Full-Scale Anaerobic Digestion Plants in South Korea: Effect of Feedstock and Operational Parameters." Energies 14, no. 3 (January 28, 2021): 665. http://dx.doi.org/10.3390/en14030665.
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In this study, the microbiomes linked with the operational parameters in seven mesophilic full-scale AD plants mainly treating food waste (four plants) and sewage sludge (three plants) were analyzed. The results obtained indicated lower diversity and evenness of the microbial population in sludge digestion (SD) plants compared to food digestion (FD) plants. Candidatus Accumulibacter dominated (up to 42.1%) in SD plants due to microbial immigration from fed secondary sludge (up to 89%). Its potential activity in SD plants was correlated to H2 production, which was related to the dominance of hydrogenotrophic methanogens (Methanococcus). In FD plants, a balance between the hydrogenotrophic and methylotrophic pathways was found, while Flavobacterium and Levilinea played an important role during acidogenesis. Levilinea also expressed sensitivity to ammonia in FD plants. The substantial differences in hydraulic retention time (HRT), organic loading rate (OLR), and total ammonium nitrogen (TAN) among the studied FD plants did not influence the archaeal methane production pathway. In addition, the bacterial genera responsible for acetate production through syntrophy and homoacetogenesis (Smithella, Treponema) were present in all the plants studied.
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Fongsatitkul, Prayoon, Donald S. Mavinic, and K. V. Lo. "A two-phase anaerobic digestion (UASB-UASB) process: design criteria and optimal system loading capacity." Canadian Journal of Civil Engineering 22, no. 3 (June 1, 1995): 551–65. http://dx.doi.org/10.1139/l95-064.
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This research evaluated the effectiveness and feasibility of two-phase (separation acid and methanogenic phases) anaerobic digestion of simulated sewage sludge using a UASB-UASB (upflow anaerobic sludge blanket) process. Predictive models of chemical oxygen demand (COD) (soluble) removal efficiency and CH4 gas production during loading maximization and the recovery (after failure) period were made. The optimum hydraulic retention time (HRT) for the A-UASB was about 1.0 d; for the M-UASB system, two different optimum HRTs were evident, depending on the operational mode. When the UASB-UASB system was run under the maximum loading possible, the best HRT in the M-UASB was about 2.0 d, to achieve high COD removal and concurrent optimum CH4 production; after deliberate overloading, to induce failure, and subsequent system recovery, the predicted optimum HRT in the methane unit was about 2.7 d, to achieve concurrent adequate CH4 production and COD removal. There also appeared to be a restructuring of the bacterial community inside the M-UASB, during the recovery period. For overall design purposes, optimum operating HRTs of 1 and 2 d, with an internal recycle rate of 1.6 and 2.5 times the influent flow rate, are recommended for A- and M-UASBs, respectively; a conservative organic loading rate of 19 kg COD (total)/(m3∙d) is suggested. Finally, the optimum HRTA-UASB/HRTM-UASB ratio was found to be about 0.63 and HRTA-UASB/HRTsystem was 0.38, which are within the boundaries of this research project. Key words: anaerobic sludge treatment, design criteria, optimum system loading capacity, two-phase anaerobic stabilization, upflow anaerobic sludge blanket.
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Abouelenien, Fatma, Toyokazu Miura, Yutaka Nakashimada, Nooran S. Elleboudy, Mohammad S. Al-Harbi, Esmat F. Ali, and Mustafa Shukry. "Optimization of Biomethane Production via Fermentation of Chicken Manure Using Marine Sediment: A Modeling Approach Using Response Surface Methodology." International Journal of Environmental Research and Public Health 18, no. 22 (November 15, 2021): 11988. http://dx.doi.org/10.3390/ijerph182211988.
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In this study, marine sediment (MS) was successfully used as a source of methanogenic bacteria for the anaerobic digestion (AD) of chicken manure (CM). Using MS showed high production in liquid and semi-solid conditions. Even in solid conditions, 169.3 mL/g volatile solids of chicken manure (VS-CM) was produced, despite the accumulation of ammonia (4.2 g NH3-N/kg CM). To the best of our knowledge, this is the highest methane production from CM alone, without pretreatment, in solid conditions (20%). Comparing MS to Ozouh sludge (excess activated sewage sludge) (OS), using OS under semi-solid conditions resulted in higher methane production, while using MS resulted in more ammonia tolerance (301 mL/gVS-CM at 8.58 g NH3-N/kg). Production optimization was carried out via a response surface methodology (RDM) model involving four independent variables (inoculum ratio, total solid content, NaCl concentration, and incubation time). Optimized methane production (324.36 mL/gVS-CM) was at a CM:MS ratio of 1:2.5 with no NaCl supplementation, 10% total solid content, and an incubation time of 45 days.
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Kazimierowicz, Joanna, Marcin Dębowski, and Marcin Zieliński. "Taxonomic Structure Evolution, Chemical Composition and Anaerobic Digestibility of Microalgae-Bacterial Granular Sludge (M-BGS) Grown during Treatment of Digestate." Applied Sciences 13, no. 2 (January 13, 2023): 1098. http://dx.doi.org/10.3390/app13021098.
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The liquid fraction from the dewatering of digested sewage sludge (LF-DSS) represents a major processing complication for wastewater treatment facilities, thus necessitating new and effective methods of LF-DSS neutralization. This pilot-scale study examined the evolution of a Chlorella sp. monoculture into microalgal-bacterial granular sludge (M-BGS) during treatment of LF-DSS in a hybrid photo-bioreactor (H-PBR). The M-BGS reached a stable taxonomic and morphological structure after 60 days of H-PBR operation. The biomass was primarily composed of Chlorella sp., Microthrix parvicella, and type 1851 and 1701 filamentous bacteria. A greater abundance of bacteria led to a faster-growing M-BGS biomass (to a level of 4800 ± 503 mgTS/dm3), as well as improved TOC and COD removal from the LF-DSS (88.2 ± 7.2% and 84.1 ± 5.1%). The efficiency of N/P removal was comparable, since regardless of the composition and concentration of biomass, it ranged from 68.9 ± 3.1% to 71.3 ± 3.1% for N and from 54.2 ± 4.1% to 56, 2 ± 4.6% for P. As the M-BGS taxonomic structure evolved and the C/N ratio improved, so did the anaerobic digestion (AD) performance. Biogas yield from the M-BGS peaked at 531 ± 38 cm3/gVS (methane fraction = 66.2 ± 2.7%). It was found that final effects of AD were also strongly correlated with the N and TOC content in the substrate and pH value. A mature M-BGS significantly improved settleability and separability through filtration.
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Serdyukov, D. V., O. V. Kanunnikov, V. A. Akselrod, and N. G. Loyko. "Antimicrobial Properties of a Biocide Based on Quaternary Ammonium Compounds plus Polyhexamethylene Guanidine and Possible Methods of Its Deactivation." Biotekhnologiya 36, no. 6 (2020): 115–26. http://dx.doi.org/10.21519/0234-2758-2020-36-6-115-126.
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Biocidal agents (BA) are widely used in environmentally safe toilet complexes (ESTC) of passenger railcars to suppress microbial activity in fаecal sludge (FS). Subsequent disposal of BA-containing FS at municipal sewage treatment facilities adversely affects their work due to the loss of activated sludge. The antimicrobial properties of BA, based on quaternary ammonium compounds (QAC) and polyhexamethylene guanidine (PHMG), as well as methods for its neutralization, have been studied. It was confirmed that BA based on QAC and PHMG has an antimicrobial effect on various groups of bacteria, reducing their number by 10-100 or more times. It was found that FS contains two groups of microorganisms with different sensitivity to BA. Methods for deactivation of the BA antimicrobial action in FS were tested using: (1), a deactivating agent; (2), incubation with thermophilically digested wastewater sludge as a source of the microbial methanogenic community; and (3), chemical deactivation by acidification or alkalization. The highest efficiency was shown by the method of deactivation of BA via thermophilic anaerobic digestion with pretreatment of FS with a strong acid biocide, fаecal sludge of ESTC of passenger railcars, antimicrobial activity, quaternary ammonium compounds, polyhexamethylene guanidine, deactivator, methanogenic microbial community This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation.
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Sudiartha, Gede Adi Wiguna, Tsuyoshi Imai, and Yung-Tse Hung. "Effects of Stepwise Temperature Shifts in Anaerobic Digestion for Treating Municipal Wastewater Sludge: A Genomic Study." International Journal of Environmental Research and Public Health 19, no. 9 (May 8, 2022): 5728. http://dx.doi.org/10.3390/ijerph19095728.
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In wastewater treatment plants (WWTP), anaerobic digester (AD) units are commonly operated under mesophilic and thermophilic conditions. In some cases, during the dry season, maintaining a stable temperature in the digester requires additional power to operate a conditioning system. Without proper conditioning systems, methanogens are vulnerable to temperature shifts. This study investigated the effects of temperature shifts on CH4 gas production and microbial diversity during anaerobic digestion of anaerobic sewage sludge using a metagenomic approach. The research was conducted in lab-scale AD under stepwise upshifted temperature from 42 to 48 °C. The results showed that significant methanogen population reduction during the temperature shift affected the CH4 production. With 70 days of incubation each, CH4 production decreased from 4.55 L·g−1-chemical oxygen demand (COD) at 42 °C with methanogen/total population (M·TP−1) ratio of 0.041 to 1.52 L·g−1 COD (M·TP−1 ratio 0.027) and then to 0.94 L·g−1 COD ( M·TP−1 ratio 0.026) after the temperature was shifted to 45 °C and 48 °C, respectively. Methanosaeta was the most prevalent methanogen during the thermal change. This finding suggests that the Methanosaeta genus was a thermotolerant archaea. Anaerobaculum, Fervidobacterium, and Tepidanaerobacter were bacterial genera and grew well in shifted-up temperatures, implying heat-resistant characteristics.
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López-Palau, S., A. Pericas, J. Dosta, and J. Mata-Álvarez. "Partial nitrification of sludge reject water by means of aerobic granulation." Water Science and Technology 64, no. 9 (November 1, 2011): 1906–12. http://dx.doi.org/10.2166/wst.2011.386.
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Granular sludge formation was performed in a laboratory scale Sequencing Batch Reactor (SBR) fed with supernatant of anaerobic digestion of sewage sludge. This effluent was concentrated progressively in order to enhance biomass capacity without inhibiting it. During the first part of the study, ammonium nitrogen was converted to nitrate, so conventional nitrification took place. When a nitrogen load of 0.8 g N L−1 d−1 was treated, the effluent concentration of nitrite started to increase while the nitrate concentration decreased until it disappeared. So, partial nitrification was achieved. At the end of this study, a nitrogen load of 1.1 g N L−1 d−1 was treated obtaining an effluent with 50% ammonium and 50% nitrite. The volatile suspended solids concentration in the reactor reached 10 g VSS L−1. At this point the granule morphology was quite round and no filamentous bacteria was observed. The Feret's diameter was in the range between 1 and 6 mm with an average value of 4.5 mm. Roundness value was all the time higher than 0.7. Granule density increased during the experimental period, obtaining a final value of 7.0 g L−1.
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Zhu, Lei, Yuguang Li, Chong Liu, and Guibai Li. "Intermittent Microaeration Technology to Enhance the Carbon Source Release of Particulate Organic Matter in Domestic Sewage." Water 14, no. 12 (June 10, 2022): 1876. http://dx.doi.org/10.3390/w14121876.
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Domestic sewage treatment plants often have insufficient carbon sources in the influent water. To solve this problem, the commonly used technical means include an additional carbon source, primary sludge fermentation, and excess sludge fermentation, but these methods are uneconomical, unsustainable, and not applicable to small-scale wastewater treatment plants. Intermittent microaeration technology has the advantages of low energy-consumption, ease of application, and low cost, and can effectively promote anaerobic digestion of municipal sludge; however little research has been reported on its use to enhance the carbon sources release of particulate organic matter (POM) from domestic wastewater. Therefore, the effect of intermittent microaeration on the carbon source release of POM was evaluated in this study, with POM as the control test. The results showed that the release concentration of soluble chemical oxygen demand (SCOD) was the highest on day 4 under microaerobic conditions, and the concentrations of SCOD, NH4+-N, and PO43−-P in the liquid phase were 1153, 137.1, and 13 mg/L, respectively. Compared with the control group, the SCOD concentration increased by 34.2%, and the NH4+-N and PO43−-P concentrations decreased by 18.65% and 17.09%, respectively. Intermittent microaeration can effectively promote the growth of Paludibacter, Actinomyces, and Trichococcus hydrolytic fermentation functional bacteria. Their relative abundances increased by 282.83%, 21.77%, and 23.47%, respectively, compared with the control group. It can simultaneously inhibit the growth of acetate-type methanogenic archaea, Methanosaeta and Methanosarcina, with a decrease in relative abundances of 16.81% and 6.63%, respectively. The aforementioned data show that intermittent microaeration can not only promote the hydrolysis of POM, but can also reduce the loss of acetic acid carbon source, which is a cost-effective technical way to enhance the release of a carbon source of particulate organic matter in domestic sewage.