• Proceedings of the Membrane Society of Korea Conference
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• 1996.04a
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• pp.20-29
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• 1996

한외여과를 비롯한 막분리 기술은 의약 및 식품산업 등의 화학공학분야, 각종 제조업에서의 배수처리 및 물질회수 등에 널리 이용되는 실용기술로서 앞으로 활용이 기대되고 있다. 최근에 막분리 기술은 상.하수 및 배수 등의 수처리 분야에 있어서도 이용되고 있으며, 역침투에 의한 해수담수화, 정밀여과에 의한 탁질제거 등의 상수처리, 한외여과와 역침투에 의한 초순수제조, 한외여과와 RO등에 의한 잡용수도의 정화처리, 한외여과와 정밀여과를 고액분리장치로서 분뇨 및 하수처리 등과 같은 처리에 광범위하게 이용되고 있다. 또한 한외여과 등으로 유용미생물을 고농도로 유지하여 특정물질의 제거와 유용물질 등을 회수하는 Process도 개발되고 있다. 본 논문에서는 일본에 있어서 분리막을 도입한 배수처리 및 분뇨처리의 기술개발과 혐기성소화의 기능향상에 관한 연구의 현황에 관하여 소개하고, 분리막에 관한 한.일의 연구자간의 정보교환이 되었으면 한다.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.241-241
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• 2020

축산물의 수요가 증가함에 따라 가축의 사육규모 및 두수도 증가하여 가축분뇨의 발생량이 증가한다. 가축분뇨는 일반하수에 비해 고농도의 유기물, 질소, 인 등의 오염물질이 포함되어 있다. 적절한 처리 없이 하수처리장 및 수계로 유입될 경우 하수처리장 처리 효율에 영향을 미치거나 부영양화 등 다양한 문제를 야기 시킬 수 있다. 이러한 문제를 해결하기 위해 아질산화 반응을 이용하는 다양한 공정들이 연구되고 있다. 아질산화 반응은 완전 질산화 반응에 비해 질산화 단계에서 약 25%의 산소요구량이 절감되고, 탈질 단계에서 약 40%의 탄소원이 절감되는 경제적 장점이 있기 때문이다. 본 연구에서는 부피 8L의 실험실 규모 아질산화 반응조 원통형 아크릴로 제작되었고, 서울 A하수처리장 미생물을 채취하여 사용했다. 또한 SRT의 영향을 살펴보기 위하여 35℃ 동일 온도를 유지했다. 반응조 슬러지 반송 및 폐기가 없는 완전 혼합 반응조로 SRT와 HRT가 동일하게 운전하는 방법을 사용하여 SRT를 조절하는 방식으로 운전했다. SRT의 경우 8일, 6일, 4일, 2일의 변경조건을 통해서 차이를 살펴보았다. Ammonia Removal Rate(%)의 경우 각각 86%, 86%, 87%, 24%의 효율을 보였고, Nitrite Conversion Rate(%)의 경우 각각 10%, 45%, 80%, 41%의 효율을 보였다. 35℃ 실험실 규모 반응조에서 가축분뇨 유입 원수의 아질산화 반응을 유도하기 위해서는 SRT운전 조건은 4~8일, 고효율의 아질산화 반응을 유도하기 위해서는 SRT 4일 조건이 적합하다고 판단된다. 본 연구는 실제 가축분뇨 처리 효율 상승을 위해서 아질산화 공법을 도입할 경우 중요한 자료로 이용 가능할 것으로 판단된다.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.100-114
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• 2005

Organic waste, which is defined as wastes derived from various biological organisms that contain more than 40% of organic materials, is generated about 100 million tons per year in Korea. These organic wastes are now controlled by several governmental entities, under different rules and regulations, leading to the improper management and inefficient treatment. Therefore, integrated management system is primarily needed for the efficient recycling of organic waste. In this study, six kinds of organic wastes, which are food waste, sludges(sewage, waste water, night soil), animal excreta, animals and plants residues, and three kinds of recycling by-products(compost, feed, anaerobic digestion by-products) made of organic wastes, were analyzed for their physical and chemical characteristics. On the basis of this result, a possibility for the efficient recycling of organic waste was investigated.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.356-362
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• 2010

This research studied the bio-methane potential of several waste biomass materials as alternative sources for biogas production, and the laboratory procedure for measuring the biochemical methane potential was described. The wastes from four agro-industries (sewage, livestock, food wastewater treatment sludge and cattle rumen substance generating in slaughter house) were evaluated as substrates for the assay of biochemical methane potential. In order to estimate the ultimate methane yield, two empirical equations (modified Gompertz equation and exponential equation) was investigated. The ultimate methane yield of sewage, livestock, food sludge and lumen substance estimated by the modified Gompertz equation were 0.086, 0.147, 0.146, and 0.121 L $CH_{4}\;g^{-1}\;VS_{added}$, respectively. The ultimate methane yield estimated by the exponential equation were 0.109, 0.246 and 0.174 L $CH_{4}\;g^{-1}\;VS_{added}$ in sewage, livestock sludge and lumen substance. And the ultimate methane yield estimated by the exponential equation showed more high values in the range of 26.7 ~67.3% than the ultimate methane yield estimated by the modified Gompertz equation.

• Microbiology and Biotechnology Letters
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• v.9 no.4
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• pp.219-223
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• 1981

Experiments on methane gas digestion were conducted to prevent livestock pollution and develop substitute energy. When about 30(w/w)% of sludge was added to cow feces, pig feces, and poultry feces and digested at 37$^{\circ}C$ for 20 days, methane gas produced per Kg of organic matter for cow feces, pig feces, poultry feces was 131, 248 and 235 l, respectively. pH decreased slightly at first but increased gradually afterwards during digestion period. When 20, 30, and 40(w/w)% of sludge were added to the mixture of cow feces (300g) and water (200g), the volumes of gas produced were 6.1, 14.5 and 13.4 l, respectively. Volume of methane gas produced from the mixture of cow feces and saw dust was much more than that from the mixture of cow feces and rice polishings. The contents of N, K, P for digestion residues were sufficient to be utilized as a fertilizer. When methane gas digestion was carried out with cow feces in a submersible pump digester the volume of methane gas produced per Kg of organic matter was 188 l. The price of total methane gas produced at this digestion was similar to that of the electric power consumed.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.7
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• pp.387-395
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• 2015

Anaerobic mesophilic batch test of several organic wastes were carried out by a graphical statistic analysis (GSA) to evaluate their ultimate biodegradability and two distinctive decay rates ($k_1$ and $k_2$) with their corresponding degradable substrate fractions ($S_1$ and $S_2$). Each 3 L batch reactor was operated for more than 100 days at the substrate to inoculum ratio (S/I) of 0.5 as an initial total volatile solids (TVS) mass basis. Their Ultimate biodegradabilities were obtained respectively as follow; 69% swine waste, 45% dairy cow manure, 66% slaughterhouse waste, 79% food waste, 87% food waste leachate, 68% primary sludge and 39% waste activated sludge. The readily biodegradable fraction of 89% ($S_1$) of Swine Waste BVS ($S_o$) degraded with in the initial 31 days with $k_1$ of $0.116day^{-1}$, where as the rest 11% slowly biodegradable fraction ($S_2$) of BVS degraded for more than 100 days with the long term batch reaction rates ($k_2$) of $0.004day^{-1}$. For the Food Waste and Waste Activated Sludge, their readily biodegradable portions ($S_1$) appeared 89% and 80%, which degrades with $k_1$ of $0.195day^{-1}$ and $0.054day^{-1}$ for an initial 15 days and 28 days, respectively. Their corresponding long term batch reaction rates ($k_2$) were $0.003day^{-1}$ and $0.002day^{-1}$. Results from other organic wastes are addressed in this paper. The theoretical hydraulic retention times (HRTs) of anaerobic digesters treating organic wastes are easily determined by the analysis of multiple decay rate coefficients ($k_1$ and $k_2$) and their corresponding biodegradable substrate fractions ($S_1$ and $S_2$).

• Resources Recycling
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• v.7 no.3
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• pp.52-57
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• 1998

The objective of this study was to investigate the effect of cow manure as additive material on the ripening of sewage s sludge for vermistabiJization. The changes of the waste properties by ripening for 50days were observed as a function of the v various mixture ratios of sewage sludge ‘and cow manure. The pH values of the mixture wastes decreased from 7.5-7.67 to 6_ 9~7.2 by the ripening for 50days, and the mixture ratio made dIfferent pH values. The initial value of oxidation-reduction p potential (Eh) of the mixture waste was a negative (-) value indicating an unfavorable condition for earthworm after, but the v values of Eh increased with the opening time. The Increase rate at Eh value was prop$\alpha$rtional to the mixture ratio of cow m manure. The value of alkalinity was also changed into the favorable range for earthworm after 50days except for non-use of 1 the cow manure When the mixture ratio of the cow manure increased from 10% to 30%, the growth of earthworms increased h from 63.7% to 88.3 % tor the survival rate, 265% to 321% for the liveweight increasing rate and 66.7_7% to 91% for hatching f rate of the cocoons. It can be concluded that the proper content of tbe cow manure in the sewage sludge to ensure effective v vermistabilization was over 20%, when the mixture was ripened during 50 days. The quantity of ingestion and 며ectian at 20%-30% was found to be O.15--i.L18g sludge and 0 1l--O.14g solid per capacity earthworm per day, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.3
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• pp.117-127
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• 1983

An experimental research was performed employing the two stage anaerobic digestion of the mixture of the nightsoil and septic tank sludge to determine the effects of various hydraulic retention time of the digestion on chemical characteristics and treatment effeciency, thus determining the proper retention time. Results of the research are as follows, 1. Volatile-acid decreased as HRT increased. 2. Alklinity and ammonia-N tended to increase as HRT increased as did pH values, however, were observed to be constant at higher HRT values than 15 days. 3. The removal efficiencies of TBOD, TCOD and VS increased as HRT increased. 4. The removal efficiency of volatile solid decreased as VS loading increased. 5. It was observed that the rates of gas production were: 0.33 with HRT of 5 days, 0.58 with HRT of 15 days and $0.57m^3/kg$ VS fed/day with HRT of 25 days respectively. It is believed that the highest rate of gas production was at HRT of 15 days. 6. The sludge settling experiment showed that the minimum settling time required to ensure the desired underflow concentraton was estimated to be 8.6 days.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.2
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• pp.1-15
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• 1983

This paper has concentrated on estimating the possibility and mathematical analysis for the application of BFB to the treatment of nightsoil with low dilution rate. The experiment for the study of this purpose was conducted by continuous type reactor at $20^{\circ}C$, varying F/M ratio from 0.12 to 0.37 and dilution ratio from 2 to 10, and in it provided matted reticulated polypropylene sheets for the solid supports. The obtained results showed that the application of BFB to the treatment of nightsoil would be more effective than any other biological treatment process. Also, it has observed that the optimum dilution ratio was about 5 times and the optimum HRT was about 17 hours, and then it was estimated that the reactor volume and the quantity of weak water could be reduced to the extent of 70 percent and 80 percent. The experimental results of BFB could be analysed by the mathematical models applied to complete mixing activated sludge process. The substrate removal rates which were obtained by McKinney's($K_m$) and EcKenfelder's($K_e$) equation was 1.784/hr and $2.0{\times}10l/mg{\cdot}day$, and substrate was removed very rapidly compared to those of conventional type biological treatment processes. The biomass yield coefficient($a_5$), the endogeneous respiration rate(b), the synthesis oxygen demand rate($a{_5}^{\prime}$), and the endogeneous respiration oxygen demand rate(b') were 0.349, 0.0237/day, 0.495 and 0.0336, respectively.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.1
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• pp.57-64
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• 2019

We investigated influence of connected influent on the treatability of a wastewater treatment plant (WWTP), recently accepting effluent from a sludge carbonization facility. Based upon the pollutant loading rates (kg/d) of each connected influent, food waste leachate and livestock wastewater contributed to high BOD and COD loadings, while sludge carbonization facility effluent certainly contributed to T-N and $NH_3-N$ loadings. The nitrification rate in aerobic tank decreased to 55% with the carbonization facility effluent entering to the WWTP, while it was 89% with no carbonization facility effluent entering. The sludge carbonization facility effluent may need to be pretreated to reduce T-N and $NH_3-N$ loadings before entering to the WWTP for further treatment.