• Asian-Australasian Journal of Animal Sciences
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• 제29권5호
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• pp.753-758
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• 2016

Moisture content influences physiological characteristics of microbes and physical structure of solid matrices during composting of animal manure. If moisture content is maintained at a proper level, aerobic microorganisms show more active oxygen consumption during composting due to increased microbial activity. In this study, optimum moisture levels for composting of two bedding materials (sawdust, rice hull) and two different mixtures of bedding and beef manure (BS, Beef cattle manure+sawdust; BR, Beef cattle manure+rice hull) were determined based on oxygen uptake rate measured by a pressure sensor method. A broad range of oxygen uptake rates (0.3 to 33.3 mg $O_2/g$ VS d) were monitored as a function of moisture level and composting feedstock type. The maximum oxygen consumption of each material was observed near the saturated condition, which ranged from 75% to 98% of water holding capacity. The optimum moisture content of BS and BR were 70% and 57% on a wet basis, respectively. Although BS's optimum moisture content was near saturated state, its free air space kept a favorable level (above 30%) for aerobic composting due to the sawdust's coarse particle size and bulking effect.

• Asian-Australasian Journal of Animal Sciences
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• 제22권1호
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• pp.113-118
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• 2009

We investigated the structure of bacterial communities present in livestock manure-based composting processes and evaluated the bacterial succession during the composting processes. Compost samples were derived separately from swine manure, dairy manure and sewage sludge. The structure of the bacterial community was analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) using universal eubacterial primers. The genus Bacillus and related genera were mainly detected following the thermophilic composting phase of swine and dairy manure composts, and the members of the phylum Bacteroidetes were mainly detected in the cattle manure waste-based and sewage sludge compost. We recovered and sequenced limited number of the bands; however, the PCR-DGGE analysis showed that predominant diversities during the composting processes were markedly changed. Although PCR-DGGE analysis revealed the presence of different phyla in the early stages of composting, the members of the phylum Firmicutes and Bacteroidetes were observed to be one of the predominant phyla after the thermophilic phase.

• Environmental Engineering Research
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• 제18권3호
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• pp.177-189
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• 2013

Studies were carried out on the speciation of heavy metals (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) during rotary drum composting of water hyacinth (Eichhornia crassipes) for a period of 20 days. Five different proportions of cattle manure, water hyacinth and sawdust were prepared for composting. This study concluded that, rotary drum was very efficient for the degradation of organic matter as well as for the reduction of mobility and bioavailability of heavy metals during water hyacinth composting. The results from the sequential extraction procedure of heavy metals shows that rotary drum composting changed the distribution of five fractions of Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr. The highest reduction in the bioavailability factors of Pb and Cd was observed during the process. The total concentration of Cu, Cr, and Cd was very low compared to the other metals (Zn, Mn, Fe, Ni, and Pb); however, the percentage of exchangeable and carbonate fractions of these metals was similar to other metals. These results confirmed that the bioavailability of metals does not depend on the total concentration of metals. From this study, it can be concluded that the addition of an appropriate proportion of cattle manure significantly reduced the mobile and easily available fractions (exchangeable and carbonate fractions) during water hyacinth composting in rotary drum.

• 한국축산시설환경학회지
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• 제2권2호
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• pp.123-133
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• 1996

Recently, a greater interest has been placed on the methods of acration control for management of maloders during composting. This study was performed to evaluate the influence of the intermittent aeration method on the composting temperature and chemical components. Combinatoins of cattle manure and rice hulls were placed on a batch composter(3,150-L size) practically designed. The chemical properties of the produced compost were suitable for plant growth, when composting temperature was maintained in the range from 45 to $66^{\circ}C$ for 42 days. It should be noted that cooling effect of intake air was not significant because air temperature was as high as $30^{\circ}C$. Heat and aeration loss from the composter did not affect biomass decomposition by microbes during composting. Mixtures of materials with C/N ratios higher than 30 required longer composting period.

• Asian-Australasian Journal of Animal Sciences
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• 제29권4호
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• pp.594-598
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• 2016

We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems.

• 자원리싸이클링
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• 제8권4호
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• pp.39-44
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• 1999

높은 유기성분을 가지고 있으나 주로 매립에 의존하고 있는 맥주폐수 슬러지와 분뇨처리슬러지의 재자원화를 위한 이들 혼합물의 퇴비화에 관한 연구를 수행하였다. 분뇨슬러지와 맥주폐수 슬러지의 적정 혼합비는 1:1로 나타났으며 초기 시료의 pH는 퇴비내 미생물의 활동을 위한 온도상승에 큰 영향을 미치지 않았다. 또한 혼합비가 1:1인 시료의 퇴비화시 C/N 비는 10-15를 유지하여 약간 낮게 나타났으나 pH의 상승없이 퇴비화가 잘 이루어짐을 알 수 있었고 주 1회 뒤집기를 수행하는 것이 가장 효율적인 것으로 나타났다.

• 한국토양비료학회지
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• 제29권4호
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• pp.403-410
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• 1996

우분뇨와 왕겨혼합물(2:1, v/v)의 효과적인 부속방법과 퇴비화를 위해 야적식과 간헐통기 퇴석방식으로 비닐하우스 조건에서 10주일간 부숙시키면서 퇴비화 과정 중의 온도변화와 희비재료의 이화학적 환경변화 등을 조사하였다. 퇴비재료의 pH변화는 부숙초기인 1-2주경에는 8.9수준으로 상승하였다가 그 이후 중성부근으로 떨어졌으며, 4주이후부터 정치식보다 간헐통기 퇴적방식에서 빠른 안정화를 보였다. 간헐통기 최적과 정치식에서 퇴비재료의 주발효(고온발효)는 부숙개시 후 3주일과 6주일내에 끝났으며 주발효 온도에 도달도 간헐통기 퇴적방식에서 빨랐다. T-C와 잔존유기물 양의 감소는 비슷한 경향을 보였으며 T-C의 경우 간헐통기 퇴적방식이 정치방식에 비해 감소가 빨랐고, 잔존유기물의 양도 부숙의 진전에 따라 간헐통기방식에서 잔존량이 더 적고 부숙개시 후 6주부터는 정치방식과 9%정도의 차이를 나타냈다. T-N은 두 방식간에 차이가 뚜렷하여 정치식은 부숙에 따라서 점점 증가되다가 6주이후에는 2.3%수준을 유지하였고, 간헐통기방식은 분해초기에 급격한 감소를 보이나 7주 이후에는 1.8%수준을 유지되었다. C/N비의 경우는 두 방식간에 차이를 보이면서 완만히 감소되는데 6주일 후에는 안정화되어 정치식과 간헐통기 퇴적방식에서 각각 17과 21수준을 보였다. 조회분과 일반 무기성분의 함량변화는 전반적으로 부숙과 함께 증가되는 경향이며 간헐통기 퇴적방식에서 이들의 함량이 높아졌다. 본 실험에서 얻어진 결과는 비닐하우스에서 우분뇨 퇴비재료를 강제간헐통기 퇴적방식으로 퇴비화함으로서 부숙(퇴비화)기간을 단축시킬 수 있었다.

• 유기물자원화
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• 제9권2호
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• pp.93-100
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• 2001

수산가공폐수 슬러지의 농경지 이용을 목적으로 수산가공폐수 슬러지에 zeolite 및 가축분 첨가율에 따른 퇴비화 과정중 온도변화, 중량감소율, $CO_2$ 및 $NH_3$발생량 및 무기성분함량 변화 등을 조사하였다. 퇴비화과정중 온도, 총중량 감소율 및 $CO_2$발생량은 zeolite 첨가율에 따라서는 별 차이가 없었으나 가축분은 첨가율이 낮을수록 온도와 총 중량감소율이 높았으며 $CO_2$발생량은 별 차이가 없었다. 퇴비화과정중 $NH_3$ 발생량은 zeolite 첨가율 5, 10 및 20%에서 퇴비화 전기간 동안 68, 61 및 $46mg/kgvs{\cdot}hr$로서 zeolite 첨가율이 높을수록 적게 발생되었고, 가축분도 첨가율 50, 65 및 80%에서 퇴비화전기간 동안 65, 58 및 $45mg/kgvs{\cdot}hr$으로서 가축분 첨가율이 높을수록 적게 발생되었다. 따라서 수산가공폐수슬러지의 퇴비화에 zeoilte 및 가축분을 첨가함으로써 악취를 어느 정도 감소시킬 수 있을 것으로 판단되었다. T-C 및 T-N함량은 퇴비화 전에 비하여 퇴비화 후에 약간 감소하였으며, C/N율은 퇴비화 후에 약간 증가하였다. 퇴비화 전후 무기성분변화는 모든 조건에서 퇴비화 전에 비하여 퇴비화 후에 $P_2O_5$, $K_2O$, CaO 및 Na함량은 약간 증가하였으며, MgO함량은 큰 변화가 없었고, Mn함량은 큰 폭으로 감소하였다.

• 청정기술
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• 제23권4호
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• pp.345-356
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• 2017

퇴비화 과정은 유기물질을 비료와 같은 유용한 자원으로 전환하는 생물학적 과정이다. 퇴비화는 유기물과 환경조건(탄질율, 온도, 습도, 산소공급, pH 등)의 변화에 적응하는 미생물 군집의 연속적인 천이과정으로 이해될 수 있다. 우리나라에서의 유기성 폐기물을 처리하는 퇴비사의 악취는 도시화 가속화에 따른 신도시개발, 공장이나 주거지역들의 생활지역 근접화에 따라 악취를 발생시키는 원인이 되어 관공서에 민원이 제기되는등 사회적인 문제가 되고 있다. 이의 저감방안으로 퇴비사에서 우점하는 미생물을 규명하고 미생물 군집의 변화를 조사, 연구하여 생장환경에 맞게 적용하는 것은 퇴비공정의 효율적인 개선과 생산된 퇴비의 품질제어, 악취저감 측면에서 매우 중요하다. 본 논문에서는 퇴비화에 있어 최적의 운용기술과 악취발생을 저감하는 방법들을 중심으로 고찰하였다. 퇴비화 공정에서 부숙활동에 효과적인 올바른 미생물종의 선택과 개체수의 빠른 증가가 부숙을 촉진시킨다. 이에 따른 미생물 분해활동을 통한 부숙 극대화를 위한 공기량(산소), 온도, 습도 등 박테리아의 최적 생장조건을 제시하였다. 악취제거 및 수분조절기능이 있는 다공성광물을 사용했더니 악취가 현저하게 개선되어 졌다. 미생물의 생장조건을 최적화 부숙환경을 개선, 부숙을 촉진시켜 악취를 저감하는 최근기술들도 제시하였다.

• Environmental Engineering Research
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• 제25권3호
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• pp.299-308
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• 2020

Composting is among the most effective integrated waste management strategies used to recycle sewage sludge (SS) waste and generate a useful product. An encapsulated lifting system is a relatively new industrial-scale composting technology. The objective of this study was to evaluate the effectiveness of composting dewatered stabilized SS mixed with green waste using this new technology. The composting process was monitored by changes in the physico-chemical properties, UV-visible spectra, and fourier transform infrared (FTIR) spectra. The composting temperature was steady in the thermophilic range for 24 and 12 d in the intensive and maturation phases, respectively, which fulfilled the disinfection requirement. Moreover, the temperature increased rapidly to 76.8℃ within three days, and the thermophilic temperatures peaked twice and lasted longer than in traditional composting, which accelerated SS degradation and decreased the composting period necessary to obtain mature compost. FTIR spectroscopic analysis showed a diminished in methyl group derived from methylene C-H aliphatic groups because of organic matter degradation by microorganisms and an increased number of aromatic chains. The new technology may be a viable and sustainable alternative for SS management that converts waste into compost that is useful as a soil amendment.