• Journal of Animal Environmental Science
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• v.12 no.2
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• pp.85-94
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• 2006

The effects of turning frequency of in-vessel composting on ammonia emissions during composting of separated solids from swine slurry/sawdust mixtures and performance of biofiltration using the chicken manure compost were investigated. Separated solids from swine manure amended with sawdust was composted in a 226 L laboratory-scale in-vessel reactors under various turning frequency and continuous airflow (0.6 L/min.kg.dm) for three weeks. Three laboratory-scale manure compost biofilters were built to treat effluent gas from the composting of separated solid from swine manure amened with sawdust process. These experiments were continued over a period of three weeks. The composting of separated solid swine manure amended with sawdust and manure compost biofiltration system were evaluated to determine the turning frequency type that would be adequate for the rate of decomposition and compost odour reduction. The compost odour cleaning was measured based on ammonia gas concentration before and after passing through the manure compost biofilter. The average ammonia odor reduction in the manure compost biofilter was 96.9 % at R1 (no turning), 99.4 % at R2(once a day turning) and 89.0 % at R3(twice a day turning), respectively. The efficiency of ammonia reduction was mainly influenced by the turning frequency.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.38-42
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• 2000

This study was performed to define the effects of the cattle feces on aerobic composting of food wastes in vessel system. Weights of cattle feces added to food wastes of 3kg were 0.25, 0.50, 1.00 and 1.50kg, respectively. Reactors were operated with stirring for 1 hour per day by 1rpm and aeration for 2 hours per day. When the weight of cattle feces was increased, the highest temperature of sample was increased, the duration period of higher temperature was elongated, and the fluctuatio of pH was severs. When the weight of cattle feces was decreased, the final density was increased. The more cattle feces were added, the more porosity was increased, C/N ratio, salinity and conductivity were decreased. There facts denotes that the addition of cattle feces increases the efficiency of composting process and the final product of composting, namely compost.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.405-410
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• 1999

This study was performed to find the recycling performance and to provide design data during recycle solid composting system to reduce bulking agent cost, Dairy manure amended with rice hulls and recycled compost was composted in a laboratory -scale vessel by continuous aeration for 10 days. The temperature and ammonia emission variations according to the ratios of bulking agents during the primary aeration stage were surveyed. Also, the influence of fresh compost quality on the recycling performance were anlayzed. While recycled composting system were operatured. The temperature in compost was maintained in the range of 40∼60$^{\circ}C$ needed for biodegradation and death of pathogenic organisms, but the ammonia emission was different by the ratios of recycled compost. The ammonia emission increased due to the low C/N ratio(17.6), high pH value(8.1) of the recycled compost.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.2
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• pp.107-115
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• 2003

Dairy manure amended with crop and forest residues (moisture 69% wet basis, C/N 22) was composted in a 605 L pilot-scale vessel using continuous air flow (56 L/min) for 19 days. Three pilot-scale sawdust biofilters (moisture 63%, pH 5.0) were built to clean biological waste gas from the composting process. For each methods, two replicated experiments were monitored over a period of three weeks. The system was evaluated to determine the biofilter media depth that would be adequate for compost odour reduction. The compost air cleaning was measured based on ammonia gas concentration before and after passing through the biofilter. Ammonia gas removal efficiency over 3 weeks was 42, 75 and 87% at sawdust biofilter media depth levels of 202, 400 and 600 mm, respectively. Each sawdust biofilter was operated at a moisture content in the range of 60~62% (wb), a temperature from 15 to $25^{\circ}C$, an average pressure drop from 240 to 340 Pa and a detention time from 60 to 180 seconds during the biofiltration process.

• Journal of the Korea Organic Resources Recycling Association
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• v.3 no.1
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• pp.21-34
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• 1995

For development of microbial additives applicable to in-vessel composting system of food waste, thermophilic bacteria which showed amylase, protease, lipase and cellulase activity were isolated from soil, compost and food waste. Among 81 isolates, the growth characteristic of 20 strains with high enzyme activity were examined. All strains are Gram positive rod with catalase activity and 17 strains are spore formers. At $50^{\circ}C$, most of the strains were able to grow from pH 5 to pH 10 and in presence of 8% of NaCl. In trypticase soy broth, the growth of these strains was greatly increased by aeration, but decreased at elevated temperature above $50^{\circ}C$.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.2
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• pp.77-84
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• 2000

Aim to get operation factors, an In-vessel Composting of Wastewater Sludge was operated. The composting equipment is consisted of three chamber, 1st, 2nd and 3rd consequently. In the results, the temperature of fermentation had shown that 1st fermentation chamber(F/C) temperature was higher than that of 2nd and 3rd fermentation chamber. The temperature was steady in all steps during the sludge being composted, the ranges of each step were $50^{\circ}{\sim}59^{\circ}C$ of 1st F/C, $41^{\circ}{\sim}50^{\circ}C$ of 2nd F/C, and $32^{\circ}{\sim}37^{\circ}C$ of 3rd F/C. Organic material content of the end product was 28% and that of pH was 7.5. Properties of the compost which have been composted on optimized condition, were shown that is acceptable to use as a fertilizer. Even in the winter time, the composting system was working well without any trouble. According to result of investigation, the end-product of the system was satisfied with the standard for a fertilizer usage. HRT(hydraulic retention time) of entire process was appropriated to be 14 days(0.9 days at drying and 3.5, 4.4, 5.2 days at each step of fermentations, respectively).