• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.86-92
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• 2002

This study was performed to assets the operating characteristics of food waste composting and co-composting (food waste + sewage sludge) at a compelling facility. The facility was being operated successfully without being affected by kind of composting feed materials. Partial anaerobic condition was detected during food waste composting and co-com-posting, but these two composting systems were proven to be operated successfully under aerobic condition from the monitoring results of $O_2$, volatile solids reduction rate, temperature, and other parameters. The conductivity and chloride concentrations of compost were gradually increased during two composting periods, but the conductivity and chloride concentrations of co-compelling indicated lower values than those of food waste composting at final point(40 m). As a result, co-composting was turned out to be more desirable than food waste composting, considering salt problem. High correlations ($R^2$= 0.9265 for food waste composting and $R^2$= 0.9685 for co-composting) between CEC and volatile organic matter were found. Quality of composts produced from two composting process satisfied Korean heavy metal standard.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.623-633
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• 2017

Food waste has been recognized as a organic sources for composting and many research was conducted to efficiently utilize or treat. This study was to evaluate a feasibility for producing food waste compost under co-composting with mixture of food and animal waste. The mixing ratio of food and animal waste was 35% as main material, which additionally mixed 30% of sawdust for co-composting. Total days of composting experiment were 84 days and each sub samples were collected at every 7 days from starting of composting. Results showed that inner temperature in composting was rapidly increased to $70{\pm}4^{\circ}C$ within 3~5 days depending on mixing animal waste of cattle, pig, and chicken base compared to sole food waste base. Expecially, the CN ratio in the mixture of food and pig water was the highest (16.2) among compost. After finishing composting experiment, maturity was evaluated with solvita and germination test. Maturity index (MI) of the mixture of food and animal waste was ranged between 6~7, but was 3 in sole food waste. Calculated germination index (GI) was at the range of about 100 irrespectively of mixing of food and animal waste. However, NaCl content and heavy metal as Cr, Cu, Ni, Pb, and Zn contents was increased in the mixture of food and animal waste. which was the highest in compost mixed the food and pig waste. Both MI and GI showed that manufactured fertilizer was suitable for fertilizer criteria while sole food waste was not adequate for composting due to composting periods. Overall, mixing the food and animal waste can be utilized for improving compost maturity, but more research should be conducted to make high quality of food waste compost with animal waste in agricultural fields.

• Hwankyungkyoyuk
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• v.6 no.1
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• pp.174-184
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• 1994

The purpose of this was to investigate the citizen‘s attitude to the food waste composting as a mean of municipal solid waste recycling. Approximately 900 questionaires were distributed to Seoul, Kangwon province and some other provinces. Most of people recognized that the composting of food waste is necessary for organic waste recycling minimization. Also, they think that a systematic education for domestic waste composting is required. They are willing to participate in the community basis small scale facility composting.

• Journal of Korea Society of Waste Management
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• v.34 no.2
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• pp.140-147
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• 2017

This study was conducted to evaluate the effects of physical characteristics. Twelve specific odorous compounds and various sources of bacteria were tested via treatment of food waste using an ultra-thermophilic aerobic composting process. Food waste was mixed with seed material and operated for 47 days. During composting, the temperature was maintained at $80-90^{\circ}C$. The variations in $O_2$, $CO_2$ and $NH_3$ production suggested typical microorganism-driven organic decomposition patterns. After composting, the concentrations of 12 specific odorous compounds other than ammonia did not exceed the allowable exhaust limits for odor. After composting, thermophiles represented 50% of all bacteria. After composting, the percentage of thermophile bacterial increased by 15%. Therefore, both stable composting operation and economic benefit can be expected when an ultra-thermophilic composting process is applied to food waste.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.1
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• pp.23-31
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• 1996

The heavy metal concentration in mixed and separately collected household food waste, and their compost during the composting period was analysed. The mixed and separately collected food waste had Cd content of 8 mg/kg in spring and its content of 13 mg/kg in winter respectively. Its content was higher than by-product compost limit value(5 mg Cd/kg). Cd concentration in separately collected food waste in a house was higher in January, February, April and May than by-product compost limit value (5 mg Cd/kg). When Cd concentration in the initial composting material was higher than 5 mg/kg, its concentration in the compost of household food waste during the composting period was higher than by-product compost limit value, but it was not accumulated in the compost during the composting period. Fly ash was added to separately collected household food waste to adjust its moisture content for composting. Its addition had moisture conditioning and Cd concentration reducing effect in the compost. The average one month composted fresh compost from the mixed collected household food waste was matured in a pile out of doors for 7 months with turning the pile once a month and its heavy metal concentration was examined. Accumulation of the heavy metals in the compost did not occur during the composting period, because they were washed out during the rainfall.

• Journal of Environmental Science International
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• v.20 no.1
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• pp.137-146
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• 2011

In this research, food waste source reduction model for apartment was investigated. In spite of prohibition of direct landfill of food waste and continuous efforts made by government and local government, food waste production increases steadily. Recycling ratio of the food waste increases every year, but its products have many problems like low quality, stability, salt, odor etc. Household occupies 63.3% of whole food waste production and this is subject to be a key factor to control food waste. We surveyed S apartment in Kwangju city as a model case, in which administrative office and women's association adopted clean plate eating, separation of raw food waste and earth worm composting as a series of method for source reduction and recycling inside the apartment. With the help of residents' participation and practice, food waste production decreased 15.6% from 0.31 g/capita/day in 2007 to 0.26 g/capita/day in 2009 (domestic average 0.30 g/capita/day). Separation of raw food waste and its composting using earth worm were very effective, and were subject to resolve the problems of present food waste treatment technologies. And earth worm composting was very useful in environmental, economical, societal and educational aspects. Instead of economical incentive, educational programs about food value, environmental problem and critical method for food waste separation were more effective for promotion of source reduction. From the analyses on the process and success factors in this model, we could conclude that leader's role was one of the key factors for the settlement of source reduction, and that was to understand the seriousness of the food waste and to seek solution, to test techniques, and to practice by oneself. Furthermore, networking and collaboration among residents, local government, NGO and local press promoted residents' participation, and it was through various education and investigation. Finally, source reduction and self recycling model of food waste in the apartment, that applies separating raw food waste and earth worm composting based on the collaboration among residents, local government, NGO, and local press, should be disseminated, and environmental policy also should be changed to make it possible.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.588-597
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• 2017

Food waste has been recognized as a critical problem in Korea and many research was conducted to efficiently reutilize or treat food waste. Main purpose of this research was to evaluate a feasibility for producing fermented organic fertilizer with mixture of earthworm cast (EC). Four different treatments were mixed with food waste and EC at the rate of 0, 10, 20, and 30%, respectively. Total days of composting experiment were 84 days and each sub samples were collected at every 7 days from starting of composting. Results showed that inner temperature in composting was increased to $70{\pm}4^{\circ}C$ within 5~10 days depending on mixing ratio of EC. Among different treatment, the highest increase of inner temperature was observed in treatment mixed with food waste and EC 30%. After finishing composting experiment, maturity was evaluated with solvita and germination test. Maturity index (MI) of each treatment was ranged between 5~7 indicating that manufactured fertilizer was curing or finished stage. Calculated germination index (GI) was at the range of 104~116 depending on mixing ratio of EC. Both MI and GI showed that manufactured fertilizer was suitable for fertilizer criteria while control (FW only) was not adequate for composting. Overall, earthworm cast can be utilized for improving compost maturity by mixing with food waste and more research should be conducted to make high quality of food waste compost with earthworm cast in agricultural fields.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.22-27
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• 2002

The composting practice has been recognized as the most popular way of controlling food waste and many attempt have been made in the field to establish more efficient and economical process. Some of the efforts are mixing cured compost with sawdust as alternative bulking agent, seeding commercially produced microorganism and/or combination of above. However, verification of such efforts is often restricted because of either the lack of engineering consideration on the limitation of composting facility scales. In this study, the effect of mixing materials in food waste composting was investigated by controlling the combination and the mixing ratio of them. When the cured compost was mixed with saw dust. the decomposition of organic material was proven to be more active by observing the compost temperature, the oxygen (O$_2$) consumption, and the cumulative carbon dioxide ($CO_2$) profile. However, the quantity of compost mix-ing seemed not to influence the reaction as long as the minimum required amount was mixed. The feeding of com-mercially produced microorganism had a tendency to prolong the thermophilic stage, which helped to increase the decomposition but it resulted in composting period. Regardless of the composting condition, bacteria and actinomycetes increased in population as the reaction approached to the end. The population of bacteria and actinomycetes were rel-atively higher than those of fungi and yeast throughout the reaction.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.4
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• pp.103-111
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• 2002

The purpose of this study is to investigate influence of NaCl precisely in recycling process of food waste and in places where food waste compost is used, because NaCl with food waste has caused concerns of adverse effects in the process of food waste recycling and in plates where final products is used. The influence of NaCl in composting was measured through temperature, concentration of carbon dioxide ($CO_2$) and pH. NaCl didn't cause bad effects until 1%(wet base) of NaCl concentration for composting, showed adverse effects gradually at 2% and 3% and affected composting deeply at 6%. The influence of NaCl in composting was insignificant until 3% of NaCl concentration but decomposing efficiency of organic compounds was interfered with more than 3%. NaCl concentration has to be maintained less than 1%(wet base) to minimize adverse effects of NaCl in composting however NaCl concentration with food waste used in real composting facilities is so lower than 1 %(wet base) that the bad influence in food waste composting is slight. Compost(final product) was collected from real food waste recycling facilities in A city, S city, K-Gu and S-Gu and controlled NaCl concentration artificially such as 0.5%, 0.8%, 1.2%, 1.6%, 2.0%, 2.5% and 3.0% to investigate influence of NaCl on growth of plants. In results of plant test and pot experiment, according to quality of compost sampled, the influence of NaCl is insufficient until 3% and bad effects appeared clearly more than 3%. The bad effects showed less than 3% because compost sampled was not stabilized fully.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.897-905
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• 2019

To compare the composting characteristics of food waste supplemented with various bulking agents, aerated composting was performed by mixing sawdust, ginkgo leaves, insect feces, and mushroom waste at ratios of 6 : 4 (w/w). The initial temperatures (day after treatment [DAT] 3) of the sawdust, ginkgo leaves, insect feces and the mushroom waste mixtures were 39, 58, 65, and 51℃, respectively. The DAT 3 temperature was the highest in the food waste-insect feces mixture (65℃) and the lowest in the sawdust one (39℃). However, the insect feces treatment was terminated at DAT 21 because of a high water content (70.92%). The water content (DAT 56) of the composted food waste supplemented with sawdust, mushroom waste, and ginkgo leaves stood at 51.28, 39.81, and 44.92%, respectively. Therefore, the fully mature composts satisfied the water content requirement of less than 55% as recommended in the fertilizer standards of the RDA of Korea. The results of the CoMMe-101, Solvita and seed germination index methods indicate that the mushroom waste and ginkgo leaves treatments matured relatively quicker than that of the sawdust one. Based on the above observations, it is concluded that the mushroom waste and ginkgo leaves are more effective bulking agents compared to sawdust and as such, are recommended as suitable replacements for sawdust in food waste composting.