• 한국환경농학회지
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• 제20권3호
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• pp.150-154
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• 2001

본 연구에서는 소형 퇴비화 용기를 높이 10 cm, 15 cm, 20 cm, 뚜껑의 수평각도 $40^{\circ}$ , $50^{\circ}$ , $60^{\circ}$ , 온도 $75^{\circ}C$, $85^{\circ}C$, $95^{\circ}C$에서 포집되는 응축수의 양을 바탕으로 최적의 조건을 찾으려 하였다. 실험결과를 요약하면 다음과 같다; 높이에 관계없이 온도가 증가할수록 응축수의 포집량은 증가하였다. 뚜껑의 수평각도에 대해서는 10 cm의 경우는 수평각도가 클수록 응축수의 포집량은 감소하였고, 20 cm의 경우는 수평각도가 클수록 응축수의 포집량이 증가하였다. 반면에 B의 경우는 $60^{\circ}$ , $40^{\circ}$ , $50^{\circ}$ 의 순으로 응축수의 포집량이 감소하였다. 각각의 실험에서 에너지 변화를 보면 온도가 높아질수록 에너지 사용량이 증가하는 것으로 나타났다.

• 한국농공학회지
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• 제35권2호
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• pp.92-103
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• 1993

A sunday system with a horizontal bin-type composter was constructed and operated to evaluate its composting performance for four days for each test in October, 1992. A sundry system is one of popular systems for composting livestock manure, of which main benefit is to utilize unlimited, clean, and free solar radiation. A rectangular concrete bin(composter) with dimension of 300cm(length) X90cm(width) X60cm(height) was bedded alternatively with four lanes of aeration pipes and heating pipes, and was insulated at three walls with 50mm styrofoam. Each aeration pipe of a diameter of 25mm had 4mm perforated holes at every 15cm longitudinally, and supplied air of about 2m$^3$/min to the composter to maintain aerobic condition . A stirrer rotating at 1 rpm made one round trip every 20 minutes on the conveying chain along the the length of the composter. Five tests (Test 1~Test 5) were implemented to evaluate the composting effectiveness of a sundry system with a horizontal bin-type composter. Treatments of two levels of the mixture ratio of swine manure and paper sludge cakes(manure : paper sludge cakes= 1 : 4 and 1 : 2) and two levels of the water content(W/C ; 70% and 50%) were made to test the significance of the physicochemical properties for decomposition of the mixture materials. Temperature, C/N ratio, water content, microbial activity of the composting materials were taken measurements to evaluate its performance with the lapse of composting time for tests. A small-scale sundry system with a bin-type composter did not appear to be an appropriate system for composting livestock manure. Since heat generation by the composting materials could not overcome heat loss due to areation in a small-scale composter, a proper thermal enviroment could not be maintained to propagate massively thermopilic microorganism relatively in a short period of time. Different from the result of Chol et al.(1992) 6), a temperature variation of the composting materials did not show the peak clearly and C/N ratio didn't lower with time as expected. Mesophilic microoragnism seemed to play an important role for decomposition of the mixture materials. A sundry system with a bin-type composter may be good for a large-scale livestock farm household which may produce enough animal manure. Therefore a decision should be made very carefully to choose a system for composting livestock waste.

• 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.

• 생물환경조절학회지
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• 제2권1호
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• pp.16-26
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• 1993

A sundry system is one of popular systems for composting livestock manure, of which main honest is to utilize unlimited, clean, and free solar radiation. A sundry system with a composter of two horizontal screw-type concrete ducts at different height, was constructed and operated for three days for each test in May, 1993, to evaluate its composting performance. Four treatments of the mixture ratio of swine manure and saw dust (manure : sawdust= 1 : 1.25, 1 : 1, 1 : 0.7, 1 : 0.5) were implemented to evaluate the effect of the mixture ratio on degradation of the composting materials of a sundry system with a screw-type composter. Maximum temperature of the composting materials was over 5$0^{\circ}C$ at D1 or D2 (one or two days after operation starts) for each test. Mean C/N ratio and water contents of the materials were reduced by more than 15 and 20％, respectively. Microbial density of each test showed a typical variation with the lapse of the composting time. Mesophilic microorganism seemed to play more important role on degradation of the materials than thermophilic. A sundry system with a screw-type composter can be considered as a feasible system on basis of maturity data. The conclusion was completely reverse from that of Choi et at., although both adopted a sundry system. A further study is recommended to pursue the cause of better performance of the screw-type composter, whether it was due to affirmative weather or more efficient composter.

• Environmental Engineering Research
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• 제17권2호
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• pp.69-75
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• 2012

Composting of water hyacinth, mixed with cattle manure, rice husk and sawdust in four different proportions, was performed in a pilot scale rotary drum composter. The physico-chemical characteristics, i.e., temperature, moisture content, pH, electrical conductivity, total organic matter (OM), nitrogen dynamics and nutrients were evaluated during the 20 days composting process. The stabilities of the composts were also investigated with respirometric analysis, i.e., $CO_2$ evolution rates and oxygen uptake rate (OUR). Among all trials, trial 1 (6 water hyacinth, 3 cattle manure, 1 rice husk) indicated the best composting mix, as shown by the highest temperature profile and OM loss, and lowest $CO_2$ evolution rate and OUR.

• 한국환경과학회지
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• 제8권4호
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• pp.509-514
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• 1999

The sewage sludges and livestock manures, respectively, were composted with sawdust used for control moisture in the static piles system composter. The variations of temperature, pH, moisture, C/N ratio, inorganic content, forms of organic materials and nitrogen, and contents of heavy metals were investigated. The results were summarized as follows ; The temperature for composting the sewage sludges reached the highest temperature of 52$^{\circ}C$, after 3 days and lasted for 7 days, and then went down 3$0^{\circ}C$ after 52 days. In the case of composting livestock manures, the temperature reached to 63$^{\circ}C$ after 10 days, that lasted for 10 days, and then went down gradually. After upsetting the sewage sludges and livestock manures for composting were decreased to 30% and 36%, respectively. The contents of inorganic matters and heavy metals were changed by the characteristics of raw materials but increased gradually during composting process. The total contents of organic materials in the sewage sludges and livestock manures for composting were decreased to 7% and 9%, respectively. The contents of ether extracts, resins, hemicellulose and cellulose were decreased but those of water soluble polysaccharides and lignins were not changed. The total contents of nitrogen in sewage sludges and livestock manures were decreased to 43% and 34%, respectively.

• Environmental Engineering Research
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• 제19권1호
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• pp.67-73
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• 2014

In India, disposal of vegetable market waste along with municipal solid waste in landfills or dumpsites is creating much nuisance in terms of odor nuisance, leachate production, and greenhouse gas emission into the atmosphere. Therefore, vegetable waste with high biodegradable and nutrient content is composted in a 550-L batch scale rotary drum composter to study the degradation process and its compost properties for its potential reuse as high quality compost. A total 150 kg of working volume was fixed for composting studies with two different ratios, trial A (6:3:1) of C/N 24 and trial B (8:1:1) of C/N 30, respectively. A maximum of $63.5^{\circ}C$ and $61.2^{\circ}C$ was observed in trials A and B; an average of $55^{\circ}C$ for more than 5 days, which helped in the degradation of organic matter and reduction of total and fecal coliform. The temperature dropped suddenly after the thermophilic stage in trial B, and leachate was observed due to insufficient amount of bulking agent. Mesophilic bacteria dominated during the initial stages of composting, and reduced considerably during the thermophilic stage. During the thermophilic stage, the rise in spore-forming organisms, including spore-forming bacteria, fungi, actinomycetes and streptomycetes, increased and these were predominant until the end of the composting process. By examination, it was observed that moisture and leachate production had adverse effects on the compost parameters with higher loss of micronutrients and heavy metals.

• 한국환경농학회지
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• 제20권4호
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• pp.238-243
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• 2001

본 연구에서는 소형 퇴비화 용기의 최적 조건에서 미생물이나 퇴비화 보조제를 첨가하지 않고 가정에서 발생되는 음식물쓰레기를 매일 1 kg씩 투입하여 퇴비화를 진행하였다. 실험결과를 요약하면 다음과 같다; 퇴비화 진행과정 중 수분함량은 $51.04{\sim}53.45%$로 유지되었다. 질소는 퇴비화 진행과정에서 산화되어 암모니아성 질소 및 아질산성 질소로서 검출되지 않았다. Hemicellulose, Lignin은 시간의 경과에 따라 뚜렷한 경향을 나타내지 않았으나, Cellulose는 점차 감소하는 것으로 나타났다. 중금속의 함량은 Cu, Cd, Pb, Hg, As는 검출되지 않았고 Cr은 $9.8{\sim}13.8$ mg/kg으로 부산물 비료의 기준치 300 mg/kg보다 낮았으며, Zn은 $25{\sim}100$ mg/kg이었다. 무기성분은 $P_2O_5$ $1.32{\sim}1.71%$, CaO $1.29{\sim}1.48%$, MgO $0.41{\sim}0.49%$, $K_2O$ $0.38{\sim}0.74%$로 퇴비화 과정 중 큰 변화가 없었다. 20일 동안 퇴비화한 후 무게 감소율은 습윤 기준 67.5%, 분해율은 48%이었다. 배출된 퇴비의 숙성도는 3등급이었다.

• 한국환경농학회지
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• 제17권2호
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• pp.160-163
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• 1998

본 연구에서는 소형 퇴비화용기에서 미생물이나 퇴비화보조제를 첨가하지 않고 가정에서 발생하는 쓰레기를 매일 1kg씩 투입하면서 퇴비화를 진행 하였다.시험결과를 요약하면 다음과 같다. 1) 시기별 발생되는 음식쓰레기를 성분함량에는 큰 차이를 나타내었다.2) 실온에서 시간당 1,321.6 l 의 공기를 주입했을때 토비 중 수분함량이 74.36 ${\sim}$ 85.14% 그리고 $45^{\circ}C$에서는 시간당 472 l 의 공기를 주입했을 때 퇴비화에 적절한 수분함량을 유지할 수 있 었다.이때 가동에 필요한 전력 소비량은 한 달에 약 132kwh이였다. 3) 20일 동안의 실험결과 실온에서 약28% 그리고 $45^{\circ}C$에서는 약 44%의 유기물이 분해되었다. 4) 퇴비화 과정 중 일반 성분함량들의 변화에서 축적현상과 같은 경향은 나타나지 않았다.다만 중금속 중 Cd 과 염분의 함량에는 주의가 요구된다. 5) 생물의 여과에 의한 악취의 제거는 $45^{\circ}C$에서는 별 문제가 없었으나 실온에서는 표면적 부하 증가 에 의하여 별 효과가 나타나지 않았다.

• 한국환경농학회지
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• 제13권3호
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• pp.338-345
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• 1994

가정부엌 쓰레기의 퇴비화를 위한 용기 개발을 위해 용기의 벽을 보온을 하지 않은 용기 (type 2)와 보온을 한 용기 (type 1)을 고안하여 계절별 가정용 음식 쓰레기의 퇴비화에 적용하였다. 일반적인 퇴비화 과정에서 볼수 있는 미생물상의 변동상이 본 퇴비화 실험에서도 관찰되었다. 그러나 형태학적, 배양학적 특성으로 동정한 결과 방선균 종류는 Streptomyces, Nocardia 사상균 종류는 Mucor, Absidia, Aspergillus, Penicillium, Rhizopus 속만이 관찰되어 미생물상이 비교적 단순하였다. 겨울에는 고온성 미생물이 ${\alpha}-amylase$를 많이 분비하였으나 여름에는 중온성 방선균이 많이 분비 하였다. protease는 여름철에 다른 효소와 거의 같은 비율로 생성되고, lipase는 중온균이 보다 많이 분비하였다. cellulase는 사상균에서는 Aspergillus속 균주만이 분비함이 확인되었다. 전체적으로 여름철에 효소 분비능이 타 계절에 비해 크게 나타났다. 계절별 용기내의 온도 상승과 미생물의 변동양상에서 여름철, 봄철, 겨울철 순으로 성장률이 활발하였다.