• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.1
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• pp.13-21
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• 1996

For treating tannery wastewater containing high sulfate and heavy metals, test was performed to assess their performance, competition between SRB (sulfate reducing bacteria) and MPB (methane producing bacteria), and the activity of MPB according to change of chromium concentrations. COD removal efficiency was above 70% at VLR (volumetric loading rate) of 2.0 gCOD/I.day and HRT (hydraulic retention time) of 18hrs at $35^{\circ}C$. In the competition between SRB and MPB, about 15% of the removed COD was utilized by SRB in the begining, but it became 43% at the end. It indicated that MPB was strongly suppressed by the occurrence of significant sulfate reduction since a large electron flow was uptaken by SRB. For the entire experiment, removal efficiencies of chromium concentration were more than 90%. Despite high removal efficiencies of chromium concentration, performance of reactor did not change significantly during the experimental periods. Expecially, chromium (III) is tannery wastewater is less toxic than chromium (VI).

• Journal of Korean Society of Water and Wastewater
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• v.9 no.2
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• pp.127-135
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• 1995

The purpose of this study was to more fully evaluate the potential for chlorophenol degradation in anaerobic sludge. The pH effects on the ring cleavage of phenol and dechlorination of monochlorophenol isomers and dichlorophenl isomers. This study results are as follows ; Each of the monochlorophenol isomers were degraded in anaerobic sludge. The relatives rates were 2-Chlorophenol > 3-Chlorophenol > 4-Chlorophenol. Biodegradation results for the dichlorophenol isomers in anaerobic sludge are such as 2,3-dichlorophenol and 2,5-dichlorophenol was reductively dechlorinated to 3-chlorophenol, 2,4-dichlorophenol to 4-chlorophenol, 2,6-dichlorophenol to 2-chlorophenol. The two dichlorophenol isomers which did not contain an ortho Cl substituent 3,4-dichlorophenol and 3,5-dichlorophenol were persistent during the 6-week incubation. The rate of dechlorination was enhanced by the presence of a Cl group ortho, rather than para, to the site of dechlorination.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.652-654
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• 2009

퇴비화는 유기물질이 분해되는 조건에 따라 호기성 퇴비화(Aerobic composting)와 혐기성 퇴비화(Anaerobic composting)로 대별된다. 음식물쓰레기 퇴비화 시설의 주요공정은 선별시설, 혼합 및 발효시설, 불순물제거장치, 숙성시설, 악취제거시설로 구성된다. 본 과제에서는 이와 같이 음식폐기물 처리공정 등에 널리 사용되는 퇴비화 공정에서 발생하는 악취를 제거하기 위한 연구를 진행하였다. 본 연구에서는 다양한 형태의 탈취 공정을 비교 검토하였으며, 세라믹 담체를 사용한 생물학적 처리에 초점을 맞추어 연구를 진행하였다. 이를 위하여 퇴비화 온도에 따른 유기물의 변화와 NaCl의 농도변화를 측정하여 퇴비화 진행에 따른 성분 변화를 예측하였다.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.197-200
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• 2003

In oil-contaminated environments, anaerobic biodegradation of toluene depended on the concentration and distribution of terminal electron acceptor as well as the physicochemical properties such as DO concentration, redox potential and pH. This study showed the anaerobic biodegradation of toluene in two different soils by using nitrate reduction, ferric iron reduction, sulfate reduction and methanogensis. Toluene degradation rates in the soil samples taken from rice filed and tidal mud flat by nitrate reduction were higher than those by other processes. Tho soil samples from the two fields were enriched for 130 days by providing toluene as a sole carbon source and nitrate or sulfate as a terminal electron acceptor. The toluene degradation rates in the enriched denitrifying consortia obtained from the rice field and tidal mud flat soil were 310.7 and 200.6 $\mu$mol$ L^{-1}$ / $d^{-1}$, respectively. The toluene (legradation rates in the enriched sulfate-reducing consortia from the fields ranged fi-om 149.1 to 86.1$\mu$mol $L^{-1}$ / $d^{-1}$ .

• Environmental Analysis Health and Toxicology
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• v.18 no.3
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• pp.193-197
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• 2003

슬러지로부터 발생하게 되는 인체에 유해하고 독성이 강한 악취물질들은, 대다수 슬러지내의 단백질, 탄수화물등의 물질들이 미생물의 호기성 및 혐기성 분해과정을 통해서 생성되는 유ㆍ무기 물질들을 포함하게 된다. 슬러지로부터 발생하는 주된 악취물질로서 hydrogen sulfide, methanethiol, dimethyl sulfide, dimethyldisulfide,dimethyltrisulfide등이 발견되어졌는데 이 다섯 종의 악취물질들은 모두가 황을 포함하는 물질들이다. 본 논문에서는 인체에 유해한 슬러지 악취의 강도 및 세기를 결정하고 비교하는 데 이용되어 질 수 있는 odor index(ODI)라는 방식이 제시되어졌다. 세가지 종류의 슬러지, 즉 hypochlorite 용액으로 처리한 슬러지와 향수 물질로 처리한 슬러지 및 아무런 처리를 하지 않은 슬러지 세 종류를 대상으로 30일이 넘는 기간동안 인체에 유해한 악취물질들에 대한 누적 odor index(ODI)값을 생성하여 비교하였다. 아무런 처리를 하지 않은 슬러지에서 가장 높은 odor index(ODI)값들이 나타났으며, 이것은 슬러지 처리에 있어서 심각한 단기 및 장기적인 유해 악취발생 문제가 야기될 수 있음을 나타낸다. 이에 대하여 hypochlorite용액으로 처리한 슬러지로부터는 인체에 유해한 악취 발생을 처리 즉시부터 30일이 넘는 기간동안 측정한계치 이하 단계로 낮출 수 있었다.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.4
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• pp.54-62
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• 1997

Disposal of blue crab wastes represents a significant problem to processors, who are limited with respect to acceptable disposal alternatives. Anaerobic bioconversion technology was investigated to determine an environmentally sound and economic disposal method for these wastes. In the study ultimate methane yield for total crab solid waste was $0.180m^3/kg$ VS added and biodegradation rate constant was $0.15day^{-1}$. Methane yield of the bench-scale reactor operated on similar feedstock was $0.189m^3/kg$ VS added and biodegradation rate constant was $0.06day^{-1}$. These results indicate that anaerobic bioconversion of blue crab wastes was technically feasible. Use of anaerobic bioconversion technology can be an attractive option for blue crab processing waste management. The by-product methane gas could be used for maintainign a number of processing operations (i.e., heat for cooking, or keeping temperature of digester constant).

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.297-297
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• 1987

A $C_{1}$ enriched cellulase fraction was separated from culture filtrate of anaerobic Clostridium thermocellum by hydroxyapatite column chromatography. The separated fraction showed strong synergistic action with $C_{x}$ component (endo-$\beta$-1, 4-glucanase) in digestion of crystalline cellulose, similar to the other aerobic cellulolytic microorganisms. Unlike the $C_{x}$ component the $C_{1}$ enriched fraction was rapidly inactivated by oxidation at the atmospheric condition. The enzyme activity was significantly enhanced by the addition of reducing agents, especially $\beta$-mercaptoethanol, which indicates that a $C_{1}$ component has a lot of sulfhydryl groups essential for the enzyme activity. The effect of metal ions on $C_{1}$ activity was also investigated. The $C_{1}$ fraction was found to be thermally stable compare to endo-$\beta$-1,4-glucanase. Optimal temperature and pH were found to be 60.deg.C and 6.0, respectively.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.2
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• pp.51-58
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• 2016

In the Integrated Two-Phase Anaerobic Digestion (ITPAD) process, acid and methane fermentation take place in one reactor, which has advantages to cope with organic load variation and reduce foot-print required, compensating disadvantages of Conventional Separated Two-Phase Anaerobic Digestion (CSTPAD). In the present work, organic matter degradation efficiency and biogas generation amount and other performance parameters of the ITPAD fed with food waste leachate were analyzed. In addition, feasibility study on the ITPAD method was performed by comparing its digestion efficiency with that of the CSTPAD. Organic matter alteration and biogas generation of the integrated method were examined for approximately 130 days based on the 5ton/day scaled pilot plant. Experiment results revealed that organic matter removal rate was 80% for mean food waste leachate input amount of $4.1m^3/day$. The biogas generation rate was $63.0m^3$ per ton of food waste leachate input, corresponding to the input VS amount of $0.724m^3/kg-VS_{added}$, and methane content of generated biogas was approximately 61.3%. The ITPAD has a comparable or higher organic matter removal efficiency compared to the conventional separated two-phase anaerobic digestion method. Consequently, the ITPAD method has a great need to commercialize a food waste leachate treatment technology against highly concentrated organic waste leachate.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.1
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• pp.109-119
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• 2002

This study is to estimate that food waste bags with biodegradable plastic are really decomposed by microorganism in composting with food waste and to examinate how biodegradable plastic affects composting. 6 kinds of 30%, 4 kinds of 100% and 2 kinds of none biodegradable plastics were used in d1is study. In 30% biodegradable plastics the highest Degradation rare is 6% in meso-condition and 10% in thermal-condition. Srain at auto break decreased to 150% in meso-condition and 120% in thermal-condition. Stress at max load were also reduced to $180kgf/cm^2$ in mesocondition and $200kgf/cm^2$ in thermal-condition. Usually, LLDPE decreased larger than HDPE in physical characreristics but HDPE is higher in degradation rate. 1n stain at auto break and stress ar max load 100% biodegradable plastic declined to 230% and to $380kgf/cm^2$ in meso-condition and to 440% and to $400/cm^2$ in thermal-condition respectively. 100% biodegradable plastics showed higher biodegradation and decomposition then 30%. They appeared clearly through SEM observation. As a result, it was not appropriate to use 30% biodegradable plastics as food waste bag because they were not decomposed perfectly. It is possible to use 100% biodegradable plastic as it but cost is too high. So development of technique is needed.

• KSBB Journal
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• v.18 no.4
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• pp.318-323
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• 2003

This study was carried out to investigate the possibility of reusing newspaper or paperbox waste by methane fermentation. When 15 g of newspaper and box wastes were digested separately for 24 days by batch fermentation, the amount of total organic acids produced were 2461 and 4978 mg/L, respectively. The tCOD removal rates were found to be 60.9 and 62.4%, respectively. In addition, the removal efficiencies of total solid were 34.8 and 33.4%, and those of volatile solid were 40.0 and 39.2%, respectively. During this period, the amounts of biogas produced were 6.95 and 6.43 L. In a semicontinuous reaction, tCOD removal efficiencies for newspaper and box wastes were 64.7 and 65.0%, respectively, after 14 days of digestion. After 25 days, which were needed to stabilize the methane fermentation, the amounts of biogas produced daily were 0.31 and 0.30 L/g.dry wt, respectively. Methane contents were 57.3 and 56.2%, respectively, and the pHs in the anaerobic acidogenic and methanogenic fermenters were 5.0 and 7.5, respectively.