• 산업기술연구
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• 제13권
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• pp.3-17
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• 1993

The composting process is a suitable to dispose the livestock manure in terms of resources recovery. However the performence of composting process is greatly affected by the environmental conditions such as characteristics of manure, type of the bulking agent, initial moisture contents, temperature, recycle and so on. The purpose of this study is to evaluate the optimum environmental conditions of composting process for livestock manures. The analytical results indicated that no bulking agent was necessary for the cow manure because of the proper C/N ratio. However the pig manure required a bulking agent since the pig manure had not only low in C/N ration but poor ventilation characteristics. In addtion, the initial miosture content for optimum composting appeared to be about 60%. The temperature control was also an essential factor to enhance the activity of thermophilic microorganisms in the laboratory composting unit. It was further found that the recycle of composts may contributed the completion of composting precess as well as C/N ratio reduction and moisture control.

• 한국축산시설환경학회지
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• 제8권2호
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• pp.115-118
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• 2002

This study was conducted to determine the effects of pig manure composting on emission of dinitrogen oxide ($N_2O$) that is greenhouse gas. Fresh pig manure was mixed with sawdust as bulking agent and moisture content of mixed compost was adjusted by 61.9%. After mixing bulking agent with pig manure that was left to compost with aeration in composting chamber for an initial period of 30 days. At the end of this period, that was decomposed and a second period of composting was conducted without aeration for 60 days. Temperature during the initial composting period was above $55^{\circ}C$ for 7 days. Moisture reduction rate by composting pig manure was 36.7%. $N_2O$ Produced during composting was 0.043g/T-Ng.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.701-710
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• 1996

Composting has gained rapid acceptance as a method of recyling relatively dry organic materials such as leaves and brush and , when alternative disposal costs are high, even moist materials such as grass clippings and dewatered sewage sludges. However, as moisture contents rise above 60% , the need for a dry bulking amendment increase the costs of composting , both by direct purchases of amendment and though increased reactor capacity and materials handling requirements. High moisture materials also present increased risks of anaerobic odor formation through reduced oxygen transport (Miller , 1991) . These costs and operational challengers often constrain the opportunities to compost high moisture materials such as agricultural manures. During the last several decades economies of scale in livestock production have been increasing livestock densities and creating manure management challenges throughout the world. This issue is particularly pressing in Korea, where livestock arms typically manage little or no cropland, and the nutrients and boichemical oxygen demand in manure pose a serious threat to water quality. Composting has recently become popular as a means of recycling manure into products for sale off the farm, but bulking amendments (usually sawdust) are expensive designed to minimize bulking agent requirements by using the energy liberated by decompostion. In this context the composting reactor is used as a biological dryer, allowing the repeated use of bulking amendment with several batches of manure.

• Animal Bioscience
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• 제35권7호
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• pp.1100-1108
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• 2022

Objective: The objective of this study was to evaluate the effect of waste cooking oil (WCO) addition on ammonia (NH₃) emissions during the composting of dairy cattle manure under two aeration conditions. Methods: The composting tests were conducted using the laboratory-scale composting apparatuses (14 L of inner volume). Three composting treatments (Control, WCO1.5, and WCO3, with WCO added at 0 wt%, 1.5 wt%, and 3 wt% of manure, respectively) were performed in two composting tests: aeration rate during composting was changed from 0.55 to 0.45 L/min in Test 1, and fixed at 0.3 L/min in Test 2, respectively. The NH₃ emitted and nitrogen losses during the composting were analyzed, and the effect of the addition of WCO on NH₃ emissions were evaluated. Results: Both tests indicated that the composting mixture temperature increased while the weight and water content decreased with increasing WCO content of the composting mixtures. On the other hand, the NH₃ emissions and nitrogen loss trends observed during composting in Tests 1 and 2 were different from each other. In Test 1, NH₃ emissions and nitrogen losses during composting increased with increasing WCO contents of the composting samples. Conversely, in Test 2, they decreased as the WCO contents of the samples increased. Conclusion: The WCO addition showed different effect on NH₃ emissions during composting under two aeration conditions: the increase in WCO addition ratio increased the emissions under the higher aeration rate in Test 1, and it decreased the emissions under the lower aeration rate in Test 2. To obtain reduction of NH₃ emissions by adding WCO with the addition ratio ≤3 wt% of the manure, aeration should be considered.

• 한국환경농학회지
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• 제32권4호
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• pp.366-368
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• 2013

BACKGROUND: Composting is the most frequently used waste management process for animal manure in Korea's livestock industry. In the composting process, a large amount of nitrogen (N) is volatilized to the atmosphere as amonia ($NH_3$). However, quantitative information of $NH_3$ emission from composting of liquid manure is required to obtain emission factors for management of livestock manure in Korea. METHODS AND RESULTS: To evaluate the $NH_3$ emission from composting of liquid manure affected by aeration, we conducted composting of liquid pig manure with three forced aeration systems. The aeration conditions were continuous (A60), cycle of 30 min aeration and 30 min pause (A30S30) and without aeration(A0). All treatments were aerated 12 hour per day with these aeration systems. The total ratio of $NH_3$ volatilization loss to total N content in liquid manure throughout composting period was estimated to 19.9% for A0 treatment, 25.9% for A30S30 treatment and 36.3% for A60 treatment. The A30S30 and A60 aeration systems increased $NH_3$ volatilization by 30.2 and 82.3% compared with systems without forced aeration. CONCLUSION(S): Ammonia emission during liquid pig manure composting was highly affected by forced aeration. The development of liquid pig manure composting systems with forced aeration would be considered both reducing ammonia emission and efficiency of composting.

• 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.

• 한국축산시설환경학회지
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• 제21권3호
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• pp.99-104
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• 2015

According to the volumetric mixing rate of dairy cow manure (DCM) and moisture control materials such as decomposed manure (DM) and sawdust (S), 6 reactors (DCM only (R1), DCM : DM = 1:1 (R2), DCM : DM = 1.5:0.5 (R3), DCM : DM = 0.5:1.5 (R4), DCM : DM:S = 1:0.5:0.5 (R5) and DCM : S = 1:1 (R6)) were used for composting of dairy cow manure. Among the composting reactors, composting reactor of R5 was shown the highest temperature of the compost as a $66^{\circ}C$ during composting period. After 3 weeks composting, moisture content of R5 and R6 were 51% and 51.3%, respectively. These values were satisfied with the moisture content standard of livestock manure compost of Korea. We concluded that decomposed manure may be a good moisture control material for dairy cow manure composting when it is used in mixture with sawdust. The optimum volumetric mixing ratio of dairy cow manure and moisture control materials was 50% of livestock manure, 25% of decomposed manure and 25% of sawdust.

• 한국축산시설환경학회지
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• 제21권2호
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• pp.41-46
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• 2015

본 연구의 목적은 가축분뇨 자원화시설에서 배출되는 주요 악취물질을 대상으로 계절별 현장 방문 조사를 통해 전반적인 악취발생 현황을 파악하고 가축분뇨 자원화시설 운용시 효율적으로 적용될 수 있는 악취 저감대책을 설정하기 위한 기초 데이터 구축이다. 횡형 로터리 (Rotary) 교반방식의 퇴비화시설 내부의 암모니아 발생 농도는 봄철은 84.3 (${\pm}15.2$) ppm, 여름철은 115.2 (${\pm}34.7$) ppm, 가을철은 76.2(${\pm}18.9$) ppm, 겨울철은 38.1 (${\pm}10.4$) ppm으로 측정되었다. 분석 결과 여름철이 가장 높은 것으로 나타났고, 다음으로 가을철 > 봄철 > 겨울철인 것으로 조사되었다 (p<0.05). 반면 황화수소 발생 농도는 봄철은 7.46(${\pm}2.24$) ppm, 여름철은 9.42 (${\pm}2.82$) ppm, 가을철은 8.15 (${\pm}3.06$) ppm, 겨울철은 10.18 (${\pm}4.11$) ppm으로 측정되었다. 분석 결과 겨울철이 가장 높은 것으로 나타났고, 다음으로 여름철 > 가을철 > 봄철인 것으로 조사되었으나, 계절별 통계적 차이는 유의하지 않은 것으로 조사되었다 (p>0.05).

• Animal Bioscience
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• 제36권10호
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• pp.1612-1618
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• 2023

Objective: In our previous study, we observed that the addition of waste cooking oil (WCO) reduced ammonia (NH₃) emissions during laboratory-scale composting of dairy cattle manure under low-aeration condition. Therefore, this study aimed to evaluate the effect of addition of WCO on NH₃ emissions reduction during pilot-scale composting of dairy cattle manure, which is close to the conditions of practical composting treatment. Methods: Composting tests were conducted using pilot-scale composting facilities (1.8 m³ of capacity). The composting mixtures were prepared from manure, sawdust, and WCO. Two treatments were set: without WCO (Control) and with WCO added to 3 wt% of manure (WCO3). Composting was conducted under continuous aeration at 40 L/min, corresponding to 22.2 L/(min·m³) of the mixture at the start of composting. The changes in temperatures, NH₃ concentrations in the exhaust gases, and contents of the composted mixtures were analyzed. Based on these analysis results, the effect of WCO addition on NH₃ emissions and nitrogen loss during composting was evaluated. Results: During composting, the temperature increase of the composting mixture became higher, and the decreases of weight and water content of the mixture became larger in WCO3 than in Control. In the decrease of weight, and the residual weight and water content of the mixture, significant differences (p<0.05) were detected between the two treatments at the end of composting. The NH₃ concentrations in the exhaust gases tended to be lower in WCO3 than in Control. Nitrogen loss was 21.5% lower in WCO3 than in Control. Conclusion: Reduction of NH₃ emissions by the addition of WCO under low aeration condition was observed in pilot-scale composting, as well as in laboratory-scale composting. This result suggests that this method is effective in reducing NH₃ emissions in practical-scale composting.

• 유기물자원화
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• 제22권4호
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• pp.28-44
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• 2014

국내 경제성장에 힘입어 최근 30여 년 간에 걸쳐서 축산물 소비가 급격하게 늘어나고 있다. 이에 따라 국내 가축 규모는 전업화, 대형화 되는 추세에 있다. 가축 사육두수의 증가는 필연적으로 가축분뇨 발생량 증가를 초래하게 되었다. 농림축산 통계에 따르면 2013년 말 기준으로 약 47,235천 톤의 가축분뇨가 발생되었다. 이 분뇨를 처리하기 위해서 퇴비화, 액비화, 정화 그리고 혐기소화와 같은 다양한 가축분뇨 처리방법이 적용되고 있다. 가축분뇨를 퇴비화 처리 하는 시설에 있어서는 에스컬레이터식, 패들식, 스크루식 또는 로타리식 등의 4가지 종류의 교반시설이 적용되고 있다. 가축분뇨 액비화 시설의 경우에는 호기적 방법과 무산소적 방법 등의 2가지 시설이 운영되고 있다. 가축분뇨를 액비화하기 위해서 전국에 약 8천기에 달하는 액비화 시설이 설치, 운영되고 있다. 가축분뇨 정화처리 시설에서는 고액분리 처리, 2차 처리 그리고 고도 처리의 3가지 단계의 기술을 적용하고 있다. 2012년 말 기준으로 볼 때 혐기소화 처리방법에 의해서 처리된 돼지분뇨 슬러리는 약 21천 톤에 달한다. 가축분뇨 처리를 위해서 퇴비, 액비, 정화 시설, 혐기소화 시설 등을 선택함에 있어서 악취제거 효율을 높이는 것이 대단히 중요한 사안이 되었다. 본 연구에서는 국내에 설치된 가축분뇨처리 시설의 특징과 운영방식을 6년간에 걸친 시설 설치관련 서류 검토와 현장조사를 통하여 분석하였다.