• Membrane and Water Treatment
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• v.3 no.1
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• pp.1-23
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• 2012

The coupling of anaerobic biological process and membrane separation could provide excellent suspended solids removal and better biomass retention for wastewater treatment. This coupling improves the biological treatment process while allowing for the recovery of energy through biogas. This review gives a basic description of the anaerobic wastewater treatment process, summarizes the state of the art of anaerobic membrane bioreactors (AnMBRs), and describes the current research trends and needs for the development of AnMBRs. The research interest on AnMBR has grown over the conventional anaerobic processes such as upflow anaerobic sludge blanket (UASB). Studies on AnMBRs have developed different reactor configurations to enhance performances. The AnMBR performances have achieved comparable status to other high rate anaerobic reactors. AnMBR is highly suitable for application with thermophilic anaerobic process to enhance performances. Studies indicate that the applications of AnMBR are not only limited to the high strength industrial wastewater treatment, but also for the municipal wastewater treatment. In recent years, there is a significant progress in the membrane fouling studies, which is a major concern in AnMBR application.

• Journal of Korean Society on Water Environment
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• v.18 no.2
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• pp.151-157
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• 2002

Landfill leachate is one of highly contaminated and heterogeneous wastewater. The leachate from initial landfill can be treated by anaerobic process because it contains biodegradable matters, particularly, volatile fatty acids (VFAs). However, the anaerobic treatment of leachate is generally required longer hydraulic retention time (HRT) than aerobic process and another treatment process to satisfy effluent concentration. Therefore the modification of conventional anaerobic treatment is needed. Two phase anaerobic membrane process (TPAMP) is an integrated membrane process to be able to separate anaerobic metabolism into two phase which are acidogenesis and methanogenesis for improvement of anaerobic treatment efficiency. In this study, the efficiency of TPAMP and conventional anaerobic treatment were compared in terms of HRT, effluent SCOD, VFAs Membrane used in TPAMP was the UF of capillary type with the surface area of $0.048m^2$. The average effluent SCOD of conventional anaerobic treatment was 1352 mg/L and the removal was 96 % at HRT 60 days, while in TPAMP, 927 mg/L and 98% at HRT 30 days.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.3
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• pp.299-306
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• 2008

This study has been conducted to derive the bio-energy, hydrogen and methane production, from mixture of food wastewater and swine wastewater, the high strength organic wastewater and to increase effluent quality. To overcome this limitation in one-phase anaerobic process, two-phase anaerobic process combining hydrogen fermenter and methane fermenter was applied. In this system $2,323ml\;H_2/L$ was produced daily from Run II where 500 ml of heattreated sludge in methane fermenter was injected, and methane produced from methane fermenter did not show big difference regardless of the amount of returning sludge at each Run. It was concluded that the two-phase anaerobic process was the appropriat process to produce hydrogen and methane simultaneously and stably. Influent $TCOD_{Cr}$ to two-phase anaerobic process showed the range of 132~145 g/L(average 140 g/L), and effluent $TCOD_{Cr}$ range was 25~40 g/L(average 32 g/L), and organic removal efficiency showed 71~82%(average 76.3%).

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.2
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• pp.99-108
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• 1998

Results obtained from this research showed that the anaerobic contact process was applicable to pear waste with COD removal efficiencies of up to $95\%$ depending on conditions, provided ammonium and phosphate salts were added as well as other nutrients, present in the commercial fertilizer, Milorganite or in yeast extract. These latter materials were required in minimum concentrations of 5 and 1.5 g/L, respectively, in the feed independent of HRT and volatile solids loading rate, with part of the effect due to the mineral fraction. Digestion was satisfactory over the whole range of volatile solids loading rates and liquid retention time of 30 to 0.5 days tested, although treatment efficiency dropped off noticeably between 1 and 0.5 day liquid retention time because of poorer flocculation and separation of anaerobic bacteria. Settling of anaerobic bacteria including methane producing bacteria was related to settling of mixed liquor suspended solids only at 1 to 5 days liquid retention times, at other liquid retention times anaerobic microorganism settled markedly less efficiently than mixed liquor suspended solids. Further studies are being made to provide information of practical and basic interest. Data on the composition of the active fraction of yeast extract might solve many practical nutrient problems encountered with the anaerobic contact process and improve its economics. Further improvement in the flocculation and settling of anaerobic bacteria as well as other bacteria would improve overall performance and allow the use of shorter liquid retention times with dilute waste. Knowledge about the numbers of methane formers present would allow a degree of understanding and control of the process not presently attainable.

• Journal of Animal Environmental Science
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• v.11 no.2
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• pp.97-102
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• 2005

Anaerobic decomposition is one of the most common processes in nature and has been extensively used in waste and wastewater treatment for several centuries. New applications and system modifications continue to be adapted making the process either more effective, less expensive, or suited to the particular waste in question and the operation to which it is to be applied. Animal manure is a highly biodegradable organic material and will naturally undergo anaerobic fermentation, resulting in release of noxious odors, such as in manure storage pits. Depending on the presence or absence of oxygen in the manure, biological treatment process may be either aerobic or anaerobic. Under anaerobic conditions, bacteria carry on fermentative metabolisms to break down the complex organic substances into simpler organic acids and then convert them to ultimately formed methane and carbon dioxide. Anaerobic biological systems for animal manure treatment include anaerobic lagoons and anaerobic digesters. Methane and carbon dioxide are the principal end products of controlled anaerobic digestion. These two gases are collectively called biogas. The biogas contains $60\~70\%$ methane and can be used directly as a fuel for heating or electrical power generation. Trace amounts of ammonia and hydrogen sulfide ($100\~300\;ppm$) are always present in the biogas stream. Anaerobic lagoons have found widespread application in the treatment of animal manure because of their low initial costs, ease of operation and convenience of loading by gravity flow from the animal buildings. The main disadvantage is the release of odors from the open surfaces of the lagoons, especially during the spring warm-up or if the lagoons are overloaded. However, if the lagoons are covered and gases are collected, the odor problems can be solved and the methane collected can be used as a fuel. Anaerobic digesters are air-tight, enclosed vessels and are used to digest manure in a well-controlled environment, thus resulting in higher digestion rates and smaller space requirements than anaerobic lagoons. Anaerobic digesters are usually heated and mixed to maximize treatment efficiency and biogas production. The objective of this work was to review a current anaerobic biological treatment of animal manure for effective new technologies in the future.

• Journal of Environmental Health Sciences
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• v.19 no.4
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• pp.38-43
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• 1993

The characteristics of food wastewater treatment in an anaerobic packed bed reactor (APBR) with polyurethane as a packing material and sludge bed reactor (ASBR) was studied. The reactor of 9cm-ID, 150cm-height was fed in a continuous mode from bottom of reactor. For the purpose of constant temperature of reactor, water jacket was installed. The used packing materials was polyurethane sponge foam. Methane which was produced by decomposed organics collected at the top of the reactor for using as a fuel. The substrates used were synthetic, mixed and food wastewater. For the acclimatization of microorganisms, mixed wastewater was used. The major analyses were gas production, COD, pH and volatile acids. Based upon the completed works, the results are as follows: When food wastewater was fed the quantity of produced gas was less than that of synthetic wastewater, but food process saw higher methane content than synthetic process. As well as COD removal efficiency of food process reached at about 85%. In aspect of effluent volatile acid, food process showed low concentration of below 500 mg/l, therefore anaerobic reaction stabled. Conclusively food wastewater used can be digested by anaerobic treatment, especially anaerobic packed bed reactor showed 82% of COD removal, 75% of methane content, 10 l of gas production, and anaerobic sludge bed reactor did 79% of COD removal, 75% of methane content, 81 of gas production at 4 kgCOD/m$^3$day, 36$\circ$C.

• Journal of Environmental Health Sciences
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• v.20 no.2
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• pp.73-79
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• 1994

The effects of packing materials in the anaerobic reactor and inorganic chemicals in the synthetic wastewater on the anaerobic treatment during the start up period were investigated using anaeroic filter process. The Ringlace and Honeycomb tube as packing materials were used in the anaerobic reactors. The Ca$^{2+}$ and Fe$^{2+}$ ion concentration as inorganic chemicals contained higher 40 times and 100 times as compared to the control synthetic wastewater, respectively. A start up period 104 and 150 days were necessary to achieve loading rate of 0.37 and 0.74 kg-Toc/m$^3$.d in the anaerobic filter process packed by Ringlace and Honeycomb tube, respectively. The loading rates of the reactor using the synthetic wastewater containing Ca$^{2+}$ (40 times) could be increased faster than in the reactors using the synthetic wastewater containing Fe$^{2+}$ ion (100 times) and control synthetic wastewater. The results of XMA analysis that a lot of the Ca$^{2+}$ ion on the surface of the anaerobic sludge in the anaerobic reactor packed by Ringlace which were fed supplied with synthetic wastewater containing Ca$^{2+}$ ion (40 times) observed as compared to the reactors supplied with control synthetic wastewater and containing Fe$^{2+}$ ion (100 times).

• Journal of Environmental Science International
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• v.28 no.2
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• pp.203-209
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• 2019

Organic wastewater generated from polyester manufacturing processes was selected from H company to investigate the feasibility of anaerobic digestion that produces gases including methane. Bio Methane Potential (BMP) tests were conducted to measure the gas production and methane concentration for 7 process wastewater and 2 kinds of sludges from the H company. Also, along with monitoring pH and alkalinity during the anaerobic digestion process, the concentrations of COD and 1,4-dioxane were measured with 4 different operating conditions for N Emulsion (NE) and Ethylene Glycol (EG) wastewater. The BMP tests showed that 65% of methane was produced from NE and EG wastewater. This suggests that the organic wastewater from H company can be effectively treated by an anaerobic digester by which more than 90% of COD was removed.

• Journal of Korean Society of Water and Wastewater
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• v.37 no.5
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• pp.253-259
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• 2023

Bioreactors are devices used by sewage treatment plants to process sewage and which produce active sludge, and sediments separated by solid-liquid are treated in anaerobic digestion tanks. In anaerobic digestion tanks, the volume of active sludge deposits is reduced and biogas is produced. After dehydrating the digestive sludge generated after anaerobic digestion, anaerobic digested wastewater, which features a high concentration of organic matters, is generated. In this study, the decomposition of organic carbon and nitrogen was studied by advanced oxidation process. Ozone-microbubble flotation process was used for oxidation pretreatment. During ozonation, the TOC decreased by 11.6%. After ozone treatment, the TOC decreased and the removal rate reached 80.4% as a result of the Ultra Violet-Advanced Oxidation Process (UV-AOP). The results with regard to organic substances before and after treatment differed depending on the organic carbon index, such as CODMn, CODCr, and TOC. Those indexes did not change significantly in ozone treatment, but decreased significantly after the UV-AOP process as the linkage treatment, and were removed by up to 39.1%, 15.2%, and 80.4%, respectively. It was confirmed that biodegradability was improved according to the ratio of CODMn to TOC. As for the nitrogen component, the ammonia nitrogen component showed a level of 3.2×10² mg/L or more, and the content was maintained at 80% even after treatment. Since most of the contaminants are removed from the treated water and its transparency is high, this water can be utilized as a resource that contains high concentrations of nitrogen.

• Journal of Animal Environmental Science
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• v.14 no.2
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• pp.113-118
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• 2008

Sequencing batch operation consists of fill, react, settle and decant phases in the same reactor. Operation consists of anaerobic, anoxic and oxic (aerobic) phases when nutrient removal from the wastewater is desired. Since the same reactor is used for biological oxidation (or mixing) and sedimentation in aerobic and anaerobic SBR operations, capital and operating costs are lower than conventional activated sludge process and conventional anaerobic digestion process, respectively. Therefore, Aerobic SBR and Anaerobic SBR operations may be more advantageous far treatment of small volume animal wastewater in rural areas.