• Korean Journal of Environmental Agriculture
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• v.13 no.3
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• pp.338-345
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• 1994

In the course of developing a small composter for dwelling house, we designed two different small bins; one is insullated (type 1) and the other uninsullated (type 2). Several interesting results were abtained from the study using these bins for garbage composting in winter, spring and summer. Changes in microbial number were very similar to those observed in the general composting process. However, microbial flora was relatively simple. The genera Streptomyces and Nocardia of actinomycetes and the genera Aspergillus, Penicillium, Mucor, Absidia, Rhizopus of hypomycetes was observed from the composted materials. Thermophiles secreted most of the ${\alpha}-amylase$ secreted in winter but mesophilic actinomycetes did in summer. The amount of secreted protease was much lower in winter than in summer. Lipases were secreted more by mesophiles than thermophiles. Only Aspergillus of hypomycetes was observed to degrade cellulose. Generally, the appearance of enzyme producing microorganisms increased in summer than in the other seasons. In the point of seasonal increase of temperature and changes in microbial flora, the number of microorganisms was higher in summer or spring than in winter.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.16-21
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• 1998

To study the possibility of agricultural utilization of sewage sludge, the changes of the substances physico-chemical and microbiological properties composting periods such as inorganic matter, the form of organic matter and nitrogen and the kinds and the population number of microorganisms were investigated. The results were summarized as follows ; Temperature and $CO_2$ generation, they were the highest in the second day of composting periods and then were gradually fallen. pH value was not changed in first day during composting periods, but in second day was rapidly increased and then it was constant of the range of 8.4∼8.6. The contents of $P_2O,\;K_2O$, CaO and Fe were a little increased during composting periods, while that of ${SO_4}^{2-}$and Mn were big increased with 253${\sim}$331% and 191${\sim}$208% in late composting periods in comparing with early composting periods, respectively. The contents of ether extracted materials, water soluble polysaccharides, hemicellulose and cellulose were decreased but that of resins and lignin were not changed during composting periods. The contents of total and organic nitrogen during composting periods were decreased with 15${\sim}$20% and 22${\sim}$35%, respectively, while that of inorganic nitrogen was decreased with 75${\sim}$116%. The population numbers of microorganism during composting periods was much too changed according to the kinds of microorganism and composting periods.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.81-88
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• 2000

Composting of N-rich wastes such as food waste and wastewater sludges can be associated loss of with substantial gaseous N, which means loss of an essential plant nutrient but may also lead to environmental pollution. We investigated the behavior of nitrogenous materials during the first high-rate phase in composting of food waste. Air dried food waste was mixed with shredded waste paper or wood chip and reacted in a bench scale composting reactor. Samples were analyzed for pH, ammonia, oxidized nitrogen and organic nitrogen. The volatilized ammonia nitrogen was also analyzed using sulfuric acid as an absorbent solution. Initial progress of composting reaction greatly influenced the ammonification of organic nitrogen. A well-balanced composting reaction with an addition of active compost as an inoculum resulted in the promoted mineralization of organic nitrogen and volatilization of ammonia. The prolongation of initial low pH period delayed the production of ammonia. It was also found that nitrogen loss was highly dependent on the air flow supplied. With an increase in input air flow, the loss of nitrogen as an ammonia also increased, resulted in substantial reduction of ammonia content in compost. The conversion ratio of initial nitrogen into ammonia was in the range of 28 to 38% and about 77~94% of the ammonia produced was escaped as a gas. Material balance on the nitrogenous materials was demonstrated to provide an information of importance on the behavior of nitrogen in composting reaction.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.453-462
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• 2000

This study was carried out to know the effect of urea addition for composting of paper mill sludge(PMS). For the purpose. PMSs containing 0%, 1.5%, 3%, and 6% urea were composted at aerated static pile(ASP) for about 80day periods. During the composting, the basic physical, chemical, and biological parameters such as temperature, color. C/N ratio, cation exchange capacity, and phytotoxic test were investigated. From the measurement of the parameters, 0~3% urea-containing PMS except for 6% urea-containing PMS showed to be normally stabilized. Thus among these treatments, 0% and 3% urea-containing PMS were applied at agitated bed system(ABS), a pilot plant of a large scale, to evaluate the possibility of practical use. Considering to the changes of the parameters investigated during composting in ASP and ABS, PMS showed to be successfully stabilized in the two facilities. However, when composted with PMS and urea, even the final PMS compost stabilized for a period enough brought out the bright grayish color. So it may be necessary to add a subsidiary amendments such as animal manure to form brown-colored products.

• Journal of the Korean GEO-environmental Society
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• v.11 no.11
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• pp.27-36
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• 2010

This study was conducted to evaluate physicochemical parameters; temperature, pH, C/N ratio, water content, organic contents and volume in a pilot-scale(capacity : $100m^3$) ultra thermophilic aerobic composting. There were three types input: municipal wasted sludge, livestock manure and slurry, and food waste produced in Jung-Eb city. Each target material was carried out by the first fermentation(organic waste + seed culture) and the second one(organic waste + seed culture + recycle compost), respectively. During composting, only with supply of air and mixing, the temperature increased $90{\sim}105^{\circ}C$ after every mixing in both periods. The changes of pH, $O_2$, $CO_2$ and $NH_3$ represented typical organic decomposition pattern by microorganisms. Also, all other physicochemical parameters of ultra thermophilic aerobic composting process showed similar or better performance than these of general aerobic composting. Heavy metal concentration of fermented compost adapted to compost fertilizer regulation standard in the heavy metal and hazardous analysis.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.247.1-247
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• 1979

분뇨는 예로부터 비료로 사용되어 왔으나 화학비료의 일반화와 수인성전염병 및 기생충 감염 등 위생적 문제 때문에 현재 그 사용이 제한되고 있으며 도시화로 인하여 분뇨의 수거지역이 그 사용지역과 밀어 이를 위생적으로 처리하기 위해 많은 비용이 소요된다. 이러한 분뇨를 적당한 수분조절제 혹은 탄소원을 혼합하여 퇴비로 만들어 토양개량제로 사용하는 방법을 확립하기 위해 본 연구에서는 실험실 규모의 퇴비제조장치를 만들어 분뇨-왕겨 혼합물의 퇴비화 최적조건을 검토하였다. 분뇨-왕겨 혼합물을 채운 퇴비제조장치를 6$0^{\circ}C$ water bath에 장치하고 수분함량, 탄소원의 양, 통기량을 변화시키면서 발생하는 $CO_2$, NH$_3$의 량을 측정하여 퇴비화속도를 측정하였다.

• Clean Technology
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• v.23 no.4
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• pp.345-356
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• 2017

The composting is a biological process that converts organic matter into useful resources such as fertilizers. It is a continuous transition of microbial communities to adapt changes in organic matter and environmental conditions (carbonation rate, temperature, humidity, oxygen supply, pH, etc.). Most of the composting plants are located in the proximity of the residential areas. It is a general scenario where government authorities receive complaints from the local residents due to release of odor from the composting, and has become a social problem in Korea. Identification of dominant microorganisms, understanding change in microbial communities and augmentation of specific microorganism for composting is vital to enhance the efficiency of composting, quality of the compost produced, and reduction of odor. In this paper, we suggest the optimum operation conditions and methods for compost depot to reduce odor generation. The selection of the appropriate microorganisms and their rapid increase in population are effective to promote composting. The optimal growth conditions of bacteria such as aeration (oxygen), temperature, and humidity were standardized to maximize composting through microbial degradation. The use of porous minerals and moisture control has significantly improved odor removal. Recent technologies to reduce odor from the composting environment and improved composting processes are also presented.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.3
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• pp.71-76
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• 1987

The purpose of this study was to know reduction of organic matter, degree of humification and composting period by corp. posting of night soil sludge. Laboratory reactor was used for this study. Samples being used in this experimentation was sludge of night soil treatment plant. The degree of composting was investigated by changing moisture content. The laboratory study indicated that the degree of humification was about 175, C/N ratio was about 11~13, composting period was about 10 days and COD reduction was 37mg/l/day in case of 60% moisture content.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.4
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• pp.53-68
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• 2020

The concentrations of ammonia, hydrogen sulfide and fine dust were measured in the compost facility of a full-time Hanwoo breeding farms. The experiments were conducted in stack type composting facility(T1) and mechanical-stirred composting facilities(T2, T3). In the stack type composting facility, the highest temperature of compost pile was 46℃, and in the two mechanical-stirred composting facilities, it rose to 63℃ and 68℃, respectively. The concentrations of PM2.5 at T1, T2 were 15 ㎍/㎥ and 5~10 ㎍/㎥, respectively. And the concentration of PM2.5 at T3 was below 10 ㎍/㎥. The highest concentration of ammonia generated at T1 was 4 ppm, but no hydrogen sulfide was detected. The ammonia concentrations at T2 and T3 were 3 ppm and 4 ppm, respectively. However, hydrogen sulfide was not detected in both facilities. At T3, the ammonia concentration increased to 65 ppm at the point where the compost was stirred with a mechanical agitator. During composting period, the pH of the compost pile decreased from 9.06 to 8.94 and then increased to 9.14 as the composting period elapsed. The NaCl content of compost was 0.09% after composting process was complete. Moisture content of compost decreased from 65.9% to 62% as composting progressed. As composting proceeded, the content of volatile solids decreased from 65.6% to 64.7% and the content of TKN decreased from 1.327% to 1.095%.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.179-187
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• 1996

This study was conducted to investigate the possibility of composting of household garbage. The composter with the double layer walls was operated for 60 days in each season. The following results were obtained at the end of the experiment, if the time was not specified. 1) The maximum temperature was $31^{\circ}C$ in spring, $36^{\circ}C$ in summer and $50^{\circ}C$ in winter. 2) The mass was reduced to an average of 58.5%. 3) pH values of the compost were 8.21 in spring, 8.29 in summer and 7.94 in winter. 4) The ash contents were 55.8% in spring, 57% in summer and 73.8% in winter. 5) The nitrogen contents were in the range of $0.2{\sim}5.8%$. Its values were the highest in winter and the lowest in summer. 6) Inorganic contents of the compost were in the range of : $P_2O_5$ ; $1.5{\sim}4.41%$, $K_2O$ ; $0.02{\sim}1.31%$, CaO $0.13{\sim}1.68%$ and MgO $0.05{\sim}1.22%$. 7) Heavy metal contents of the compost were in the range of : Zn ; $13{\sim}89mg/kg$, Cu ; $4{\sim}62mg/kg$, Cd ; $1{\sim}21mg/kg$, Pb ; $N.D.{\sim}97mg/kg$, Cr ; $N.D.{\sim}37$ and Hg ; $N.D.{\sim}1.38mg/kg$.