• Journal of Environmental Impact Assessment
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• v.8 no.2
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• pp.65-71
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• 1999

Characteristics of food garbage discharged from primary schools in Seoul Metropolitan city were analysed from a recycling point of view. The results of study are epitomized as follows : 1. Factors of generation of food garbage are mainly an unbalanced diet habit, indifference of class teachers, and worn-out cooking equipments. 2. Measures of reduction are principally a written message to parents, broadcasting in the school, and instructions. 3. Methods of recycling are mainly feed stuff, composting by school itself, composting on commission, and making feed stuff on commission. 4. Obstacles of food garbage recycling are a nasty smell of composting apparatus, an excessive fuel consumption of composting apparatus, a high concentration of salt, and an unstable demand for feed stuff and compost produced from food garbage. 5. Correlation factors are like follows : the number of feeding children and food garbage weight after cooking is 0.35, total food garbage generated and monthly treatment cost of food garbage is 0.20, individual school lunch expenses and food garbage weight after cooking is -0.10, individual school lunch expenses and food garbage generated per capita is 0.02, and individual school lunch expenses and monthly treatment cost of food garbage is 0.03.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.925-934
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• 2010

Three typical biological solid wastes, namely, animal manure, garbage, and sewage sludge, were compared with regard to the composting process and the changes in microbial community structure. The effects of different bulking agents such as rice straw, vermiculite, sawdust, and waste paper were compared in manure compost. The differences in the microbial community were characterized by the quinone profile method. The highest mass reduction was found in garbage composting (56.8%), compared with manure and sludge (25% and 20.2%, respectively). A quinone content of $305.2\;{\mu}mol/kg$ was observed in the late stage of garbage composting, although the diversity index of the quinone profile was 9.7, lower than that in manure composting. The predominant quinone species was found to be MK-7, which corresponds to Gram-positive bacteria with a low G+C content, such as Bacillus. The predominance of MK-7 was especially found in the garbage and sludge composting process, and the increase in quinones with partially saturated long side-chains was shown in the late composting process of manure, which corresponded to the proliferation of Actinobacteria. The effects of different bulking agents on the composting process was much smaller than the effects of different raw materials. High organic matter content in the raw materials resulted in a higher microbial biomass and activity, which was connected to the high mass reduction rate.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.19-25
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• 1996

A fundamental study on composting garbage was performed in a laboratory scale of a high-speed composting reactor. Major parameters were moisture content, temperature and C/N ratio. The results are as follows; pH of the compost was the highest at moisture 60% and anaerobic condition occurred at 70%. It was, also, found that C/N ratio, caused a nitrogen loss due to an occurrence of plentiful $NH_3$. Under controlling Temperature, pH was the highest at $60^{\circ}C$ and an inverse effect for Composting occurred under excessive Temperature as pH at $70^{\circ}C$ was lower than that of soil. The variation of pH and C/N ratio was the lowest when C/N ratio was 25. The results obtained from composting garbage revealed that the best condition of composting occurred under 50 to 60% of moisture content, $60^{\circ}C$ of temperature, and 25 of C/N ratio. It is believed that composting may be finished with in 56 hours if an optimal condition is setting up.

• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.226-230
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• 2005

The microbial community during composting of gargage was analyzed using 16S rDNA PCR - DGCE (denaturing gradient gel electrophoresis). Pseudomonas spp. was found throughout the process, and thermophilic Bacillus spp. was dominated at the thermophilic stage. Six thermophilic bacteria were isolated and identified as B. caldoxylolyticus, B. thermoalkalophilus, and B. thermodenitrificans.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.73-80
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• 2000

The objective of study was to evaluate the apropriate maturity indices for garbage composting using sawdust as bulking agent. Materials used in this study were the average composition garbage(G20) and garbage conditioned by sawdust(GS30, GS50) and cereals(GSC30). Indices for evaluating maturity were VS, water soluble TOC, polysaccharide, Humification Index(HI), and E4/E6. Experiment results showed that VS reduction was the most desirable index for evaluating compost maturity except for the GS50 which were conditioned with high sawdust Water soluble TOC decreased rapidly during the composting of first one month and then little changed. Therefore, water soluble TOC was recommended as maturity index. Polysaccharide was considered as a maturity index in case of garbage conditioned with sawdust and high cereals. Humification Index(HI) and E4/E6 were available as maturity indices in case of only some garbage composting so additional study was needed to confirm them as maturity indices for all garbage composting. Correlation analysis indicated that indices for evaluating maturity of garbage(about 30 C/N ratio) adding sawdust as bulking agent and high cereals, were VS reduction, water soluble TOC, polysaccharide, and E4/E6.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.2
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• pp.105-111
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• 1999

This study was performed about composting in a batch reactor of laboratory scale using garbage waste and swine waste. Sawdust and coconut peat were materials to control optimum moisture, C/N ratio and specific gravity in the study. Comparing compost using only sawdust with compost using sawdust and coconut peat, the latter was higher at reduction rate and decomposition rate. Coconut peat was accelerated aerobic fermentation, because it had moisture holding ability, initial moisture was low, ventilation was good and control of optimum specific gravity was possible. Compost by only garbage waste was under standard of manure. but mixtures in same proportion of garbage waste and swine waste producted high quality compost. CEC value was average 63.8me/100g. The initial C/N ratio of compost was regulated effectively because of high C/N ratio of sawdust. As the C/N ratio(>40) was higher, reduction rate was higher. During the composting C/N ratio was improved more and more.

• Journal of the Korea Organic Resources Recycling Association
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• v.3 no.2
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• pp.91-96
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• 1995

A questionare survey was performed to investigate the citizen's attitude toward garbage composting and compost. Most people considered that the food waste treatment problem is serious and 91.1% of people know that it is possible to make compost out of food waste. Also, people think that compost made from food waste is better than the compost made from manures. People favor vegetables grown by organic compost than those grown by chemical fertilizer and was willing to pay 10~20% more prize. Most people was willing to cooperate in source separation for garbage composting and throught that the most desirable treatment method for garbage would be composting.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.1
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• pp.75-86
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• 1994

Garbage composting was studied in a controlled batch reactor with the addition of cooked rice as a biodegradable carbon source to find the effect of C/N ratio control on composting. And composting of bulking agents such as sawdust and wheat straw were tested with the addition of ammonium sulfate as a nitrogen source. As expected, biodegradation of the garbage having low C/N ratio was improved to some extent when foreign carbon was added. But bulking agents used in this study exerted slightly biodegradable carbon potential, indicating that the estimation of the dose of additional carbon considering desirable C/N ratio was not reasonable when lignocellulosic bulking material was added to garbage. It was found that the optimum moisture content increased with sawdust addition meaning the C/N ratio increment. Considering the above results, it was suggested that 78g sawdust per 100g garbage should be mixed to make C/N ratio to 25 and moisture content to 56% for effective composting of the garbage studied in this paper.

• 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.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.735-739
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• 2007

A thermoacidophilic bacterium was isolated from the compost and designated as Bacillus sp. SJ-15 by physiological and biochemical characteristics. The optimum temperature and pH for growth were at $55^{\circ}C$ and pH 5.0, respectively. The strain SJ-15 was adapted in process of accelerated high-temperature composting of garbage. The highest viable cell count of composting process reached to $9.2{\times}10^9/ml$ in 16 hours. After running times of 100 days, the composting process showed a reduction rate of approximately 88%, and the concentrations of components were sufficiently high or low to satisfied the standard of organic compost except for salinity.