• 대한환경공학회지
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• 제29권1호
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• pp.98-105
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• 2007

본 연구에서는 초음파 cavitation을 이용한 슬러지의 전처리가 슬러지의 가용화와 혐기성 소화조의 운전효율에 미치는 영향을 바이오가스 생성을 중심으로 알아보고, 전처리의 효과를 ADM1 (Anaerobic Digestion Model No. 1)을 이용하여 시뮬레이션 한 결과와 비교하였다. 실험결과, 초음파 전처리는 하수슬러지의 탈수성을 감소시키며 SCOD의 생성을 증가시키는 것으로 나타났다. 실험실 규모의 혐기성 소화조는 초음파 미처리 슬러지(control)와 30분, 60분, 90분간 처리된 슬러지를 대상으로 4 계열로 운전되었으며, 그 처리효율은 TCOD의 경우, 각각 31.9%, 37.9%, 38.5%, 42.2%의 제거효율을 나타내었다. 또한 TS의 감량효율은 각각 15.9%, 20.8%, 21.5%, 24.1%로 평가되어 전처리에 따른 제거효율의 증가를 확인 할 수 있었고, 슬러지 부하와 전처리 시간의 증가에 따라서 바이오가스의 생성량도 증가하는 것으로 나타났다. 슬러지 전처리에 따른 혐기성 소화조의 운전결과와 시뮬레이션 결과의 추이는 전반적으로 일치하는 경향을 나타내었다.

• 유기물자원화
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• 제24권2호
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• pp.3-13
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• 2016

본 연구는 바이오가스화 처리 유 무에 따라 하수슬러지 처리방법별, 즉 소각, 탄화, 건조, 고형화 등에 대한 환경성 및 경제성 분석을 실시하였다. 추가적으로 혐기 소화효율 45 %, 함수율 95% 등 정부정책 가이드 라인에 때한 경제적 타당성 조사도 실시하여 정책수립의 과학적 근거자료로 제시하고자 하였다. 경제성 분석을 위하여 30개의 혐기소화 소유 시설과 17개 소유하지 않는 시설을 조사하였다. 결과적으로, 환경성 및 경제성을 고려할 때 혐기소화 이후 후처리로 소각 또는 건조하는 경우가 가장 타당한 것으로 분석되었으며, 후처리로 탄화처리하는 경우가 가장 타당성이 적은 것으로 분석되었다. 고형화 처리는 가장 경제적이었으나 환경적 및 운전성이 부족하여 타당성이 부족한 것으로 분석되었다.

• Environmental Engineering Research
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• 제24권4호
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• pp.662-669
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• 2019

Anaerobic digestion is a popular sewage sludge (Ss) treatment method as it provides significant pollution control and energy recovery. However, the low C/N ratio and poor biodegradability of Ss necessitate pretreatment methods that improve solubilization under anaerobic conditions in addition to anaerobic co-digestion with other substrates to improve the process efficiency. In this study, three pretreatment methods, namely microwave irradiation, ultrasonication, and heat treatment, were investigated, and the corresponding improvement in methane production was assessed. Additionally, the simplex centroid design method was utilized to determine the optimum mixture ratio of food waste (Fw), livestock manure (Lm), and Ss for maximum methane yield. Microwave irradiation at 700 W for 6 min yielded the highest biodegradability (62.0%), solubilization efficiency (59.7%), and methane production (329 mL/g VS). The optimum mixture ratio following pretreatment was 61.3% pretreated Ss, 28.6% Fw, and 10.1% Lm. The optimum mixture ratio without pretreatment was 33.6% un-pretreated Ss, 46.0% Fw, and 20.4% Lm. These results indicate that the choice of pretreatment method plays an important role in efficient anaerobic digestion and can be applied in operational plants to enhance methane production. Co-digestion of Ss with Fw and Lm was also beneficial.

• 유기물자원화
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• 제27권3호
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• pp.5-13
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• 2019

본 연구는 돈분 슬러리 단독 및 돈분과 우분슬러리 혼합, 가축분뇨 슬러리와 과실착즙박(사과착즙박, 감귤착즙박) 혼합 혐기처리가 바이오가스 발생에 미치는 영향을 규명하기 위하여 가동하였다. 6개의 중온소화 반응조를 96일간 가동하였으며, 유기물 부하량은 $1.0kg-VS/m^3{\cdot}day$ 으로 하였다. 과실착즙박이 혼합된 처리구인 돈분 슬러리와 감귤착즙박 혼합 처리구(70 : 30)가 가장 높은 메탄 생산량을 나타내었다. 반면, 돈분슬러리 단독 처리구의 메탄 발생량은 가장 적었다. 돈분, 우분 슬러리와 감귤착즙박 혼합 처리구가 돈분 슬러리 단독 처리구보다 바이오가스와 메탄가스가 2배 이상 많이 발생되었다. 돈분 슬러리와 감귤착즙박 혼합 처리구가 메탄가스 발생량이 많았던 것은 과일착즙 후 발생하는 과일박이 낮은 pH를 나타내어 가축분뇨 내 높은 알칼리도와 적절히 중화될 수 있으며, VS가 돈분슬러리보다 높았기 때문인 것으로 사료된다. 결론적으로 가축분뇨와 과실착즙박 혼합 투입이 돈분 단독 소화 보다 메탄가스 생산을 높이는 장점이 있다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.476-481
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• 2005

2004년말 현재 국내에서 발생되는 음식물쓰레기의 재활용량은 전체 발생량의 $87.7\%$인 10,015톤/일이며, 전체 재활용량의 $6.47\%$인 640톤/일 정도가 혐기성소화 방법에 의해 처리 및 자원화 되고 있다. 국내에서 적용되고 있는 음식물쓰레기 혐기성소화 기술의 대부분은 습식소화(Wet digestion) 공법이며, 처리 방법별로 2상 혐기성소화(Two-phase anaerobic digestion)와 하수슬러지 흑은 축산분뇨와 함께 혼합처리 하는 통합소화(Co-digestion) 공정으로 구분되고 있다. 음식물쓰레기의 자원화 방법에 있어 혐기성소화는 사료화, 퇴비화에 비하여 폐기물의 효과적인 감량화와 자원화 효과뿐만 아니라 유용 에너지원인 메탄가스의 회수가 가능하기에 최근에 주목을 받는 biotechnology중의 하나로 자리매김 하고 있으며, 또한 유기성폐기물의 자원순환형 관리 시스템 구현에 있어 적절한 대안으로 고려되고 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제10권6호
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• pp.541-550
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• 1997

Anaerobic chytridiomycete fungi are now well recognized as one of the major components of rumen microflora. Since the discovery of anaerobic fungi, the knowledge upon their morphology and physiology has been accumulated. It is certain that they gave roles in ruminal fiber digestion, although their quantitative contribution to rumen digestion is still unclear. Their role in fiber digestion is complicated by the dietary factors and the interaction with other microorganisms. We aim at reviewing such information in this article. Considerable attention gas been paid to the polysaccharidase of these fungi. Analysis on the fungal genes encoding these enzymes has been performed in several laboratories. This article also covers the genetical analysis of fungal polysaccharidases.

• 한국농공학회논문집
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• 제50권4호
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• pp.59-66
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• 2008

Anaerobic digestion system is getting more attractive in that it produces biogas in the process of organic waste stabilization. Net energy production is important when biogas production is concerned. In this study, net energy production was evaluated with respect to biogas production and heat losses in a hypothetical digester. Under the condition of digester operation with slurry inflow of 5% of TS, additional fuel is required to maintain digester temperature during the winder season. Substrate therefore, needs to have higher VS contents through co-digestion of silage or food waste that has greater values of methane production rate. Heating input slurry is important in cold season, which covers over 80% of heating requirement. Heat recovery from digestate is valuable to reduce the use of biogas for heating. It seems desirable to minimize slurry inflow when temperature is very low. Psychrophilic digestion may be a feasible option for reducing heating requirement.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.207-210
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• 2004

Effect of electron accepters on anaerobic degradation of petroleum hydrocarbons by an anaerobic sludge taken from a sludge digestion tank in a soil artificially contaminated with 10,000 mg/kg soil of diesel fuel was tested. Treatments of soil with 30 mL of the digestion sludge (2,000 mg/L of vss (volatile suspended solids)) were incubated under several anaerobic conditions including nitrate reducing, sulfate reducing, methanogenic, and mixed electron accepters conditions for 120 days. Treatments with the digested sludge showed significant degradation of diesel fuel under all anaerobic conditions compare to control treatments with an autoclaved sludge and without the sludge. The amount of TPH degradation after 120days incubation was the largest in the treatment with the sludge and mixed electron accepters (75% removal of TPH) followed in order by sulfate reducing, nitrate reducing, methanegenic condition as 67%, 53％, 43%, respectively. However, the rate of TPH degradation in the nitrate- and sulfate reducing condition within 105 days were comparable with that of the mixed electron accepters condition. Microorganisms in each electron acceptor condition were plated on solid mediums containing nitrate or sulfate as sole electron acceptor and several nitrate- and sulfate reducing bacteria showed effective degradation of diesel fuel within 30 days incubations. These results suggest that anaerobic degradation of diesel fuel in soil with digested sludge is effective for practical remediation of soil contaminated with petroleum hydrocarbons.

• 한국환경과학회지
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• 제23권5호
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• pp.853-859
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• 2014

The purpose of this study was to improve low digestibility in anaerobic digestion facility of the sewage treatment plant. To perform this research, sludge digestion and digestion gas purification facilities in sewage treatment plant was applied. In the result of this study, it was very effective for sludge reduction from the improvement of digestive efficiency. In addition, it was confirmed that high purity $CH_4$ (methane) was produced. This results can be useful as basic data to improve the low digestibility in anaerobic digestion processes.

• 상하수도학회지
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• 제28권1호
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• pp.55-60
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• 2014

Food waste leachate (FWL) is a serious pollutant waste coming from the food waste recycling facilities in Korea. FWL has a high organic matter content and high COD to nitrogen (COD/N) ratio, which can disturb efficient methane production in the anaerobic digestion of FWL. In the present study a microalga, Clorella vulgaris (C.V), was used as co-substrate for the FWL anaerobic digestion in order to supply nutrients, decrease the COD/N ratio and increase its methane yield. Different co-digestion mixtures (COD/N ratios) were studied by using biochemical methane potential test and modified Gompertz equation for kinetic study. Mixed substrate of FWL and C. vulgaris in the co-digestion clearly showed more the biomethane yield than the sole substrates. The maximum methane production, 827.7 mL-$CH_4$/g-VS added, was obtained for COD/N ratio of 24/1, whereas the highest improvement of methane yield was found for COD/N ratio of 15/1.