• Journal of Animal Environmental Science
• /
• v.3 no.1
• /
• pp.13-18
• /
• 1997

This study was conducted to investigate the physicochemical changes during the aerobic composting of swine manure mixed with bulking agent, sawdust(v/v, 1:1), in a full-scale composting plant using rectangular escalator-aginated bed composting system. Physical and chemical properties were analyzed on the samples which were collected at 5, 15, and 25 day of composting, curing and final step. The results of this study were summarized as follows; 1. Moisture and K2O content, and pH of final step were higher than those of 5th day of composting (p＜0.05). 2. Ammonium nitrogen, total organic corbon and organic matter content, and electrical conductivity(EC) were significantly decreased (p＜0.05) but nitrate nitrogen, ash and P2O5 content increased(p＜0.05) throughout the aerobic composting process. 3. Total organic carbon per total nitrogen(C/N) and total organic matter per total nitrogen(OM/N) ratio were significantly decreased throughout the aerobic composting process(p＜0.05). 4. Physical and chemical properties of swine manure were varied by aerobic fermentation using rectangular escalor-aginated bed composting system.

• Journal of Korea Society of Waste Management
• /
• v.34 no.2
• /
• pp.140-147
• /
• 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 Environmental Health Sciences
• /
• v.26 no.3
• /
• pp.38-42
• /
• 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.

• Journal of Environmental Health Sciences
• /
• v.31 no.2 s.83
• /
• pp.160-164
• /
• 2005

This study was performed to evaluate the effects of washing food wastes before aerobic composting on temperature, pH and salinity, and the effects of washing after composting on salinity of sample mixtures. Weight ratios of food wastes to water in washing were 1:0(Control), 1:1(W-1), 1:2(W-2), 1:3(W-3) and 1:0(N-4), respectively. Ratios of food wastes to wood chips in reactor of Control, W-1, W-2, W-3 and N-1 were $5\;kg:0\iota,\;5\;kg:5\iota,\;5\;kg:5\iota,\;5\;kg:5\iota\;and\;5\;kg:5\iota$, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours of forced aeration per day. The increase in the ratio of water to food wastes resulted in the increase of the maximum reaction temperature and the shortening of the high temperature reaction period. The increase in the ratio of water to food wastes also resulted in faster reaching to the lowest pH and then to the steady state of pH 9.0. The final salinities of Control, N-1, W-1, W-2 and W-3 were $1.04\%,\;0.92\%,\;0.78\%,\;0.64\%\;and\;0.53\%$, respectively. The salinities of the N-l samples which were washed by the weight ratios (water:N-l) of 1:1, 2:1 and 3:1 after composting were $0.72\%,\;0.61\%\;and\;0.51\%$, respectively. Therefore, washing food wastes before aerobic composting is more efficient method than that after aerobic composting.

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

• Journal of the Korean GEO-environmental Society
• /
• v.10 no.5
• /
• pp.33-39
• /
• 2009

This study was conducted to evaluate production of complex odor and 12 specific odorous compounds 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 raw material was mixed with seed material and operated for two periods (1st : 50 days, 2nd : 60days). During composting, the temperature hit $90{\sim}95^{\circ}C$ after every mixing in both periods. Therefore, it was concluded that increasing temperature also saves the time which required for composting and high reduction of organics and water contents. The primary odorous compounds were ammonia, methyl mercaltan, dimethyl disulfide and trimethylamine. The concentration of the primary compounds and complex odor during the operation were higher than those on final day and most compounds did not exceed the allowable exhaust standard for odor. Also, it was found that optimal mixing time and control of high temperature are the most important parameters for odor control in ultra thermophilic aerobic composting.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2004.06a
• /
• pp.207-209
• /
• 2004

This study was performed to estimate the effects of salinity and washing of food wastes on temperature, pH, and salinity in aerobic composting of food wastes. Weight ratios of food wastes to water in washing were 1:0(Control), 1:1(W-1), 1:2(W-2), 1:3(W-3) and 1:4(W-4), respectively. Ratios of food wastes to wood chips in reactor of Control, W-1, W-2, W-3 and W-4 were 5kg:5L, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The increase in the ratio of food wastes to water used in washing resulted in the decrease of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the ratio of food wastes to water used in washing resulted in faster pH increase The final salinities of Control, W-1, W-2, W-3 and W-4 were 0.95%, 0.73%, 0.65%, 0.57% and 0.41%, respectively.

• Journal of Environmental Health Sciences
• /
• v.30 no.1
• /
• pp.1-6
• /
• 2004

This study was performed to estimate the effects of washing of food wastes on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Weight ratios of food wastes to water in washing were 1:0(Control), 1:1 (W-1), 1:2(W-2), 1:3(W-3) and :4(W-4), respectively. Ratios of food wastes to wood chips in reactor of Control, W-1, W-2, W-3 and W-4 were 5 kg:5 1, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The increase in the ratio of food wastes to water used in washing resulted in the decrease of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the ratio of food wastes to water used in washing resulted in faster pH increase and the steady state in the weight reduction rate and the volume reduction rate of composts. The final salinities of Control, W-1, W-2, W-3 and W-4 were 0.95%, 0.73％, 0.65%, 0.57％ and 0.41％, respectively.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2003.06a
• /
• pp.208-212
• /
• 2003

This study was performed to examine the effects of chaff as bulking materials on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor Control, Ch-1, Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wastes to chaff resulted in the ascending of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more fast time of pH ascending. The lowering of the volume ratio of food wastes to chaff resulted in the more fast consistency in the weight and volume reduction rates. Salinities were condensed by reaction days. The final salinity of Control was 2.79%, and the final range of salinities of chaff mixtures was 2.18 - 2.37%.

• Journal of Environmental Health Sciences
• /
• v.29 no.2
• /
• pp.56-61
• /
• 2003

This study was performed to examine the effects of chaff as a bulking material on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor of Control, Ch-1. Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4. respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wasted to chaff resulted in the reaction at higher reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more faster pH increase. The lowering of the volume ratio of food wastes to chaff resulted in the more faster reduction in the weight and the volume of wastes. Salinities were condensed by reaction days. The final salinity of Control and the final range of salinities of chaff mixtures were 2.79%, and 2.18~2.37%. respectively.