• Journal of Animal Environmental Science
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• v.12 no.1
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• pp.29-34
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• 2006

The effects of turning frequency were examined on the efficiency of composting lime treated excess sludge amended with sawdust from the activated sludge process after a liquid/solids separation process. The raw and excess sludge from the activated sludge process associated with the hog wastewater treatment system is a significant problem and composting is an effective method far reducing the pollution potential of hog wastewater sludge. The coagulant used sludge composting and ammonia emissions from composting are not well established. The effect of compost properties such as high total carbon, C/N ratio and pH value on performance of composting sludge and biofiltration of ammonia from composting process were investigated. The ammonia emission was not significantly increased during composting. The ammonia concentrations of the exhaust air of composter were ranged from 0.5 and 7 ppm about 12 days after composting. The performance of the hog wastewater sludge composting was the most sensitive to chemical treated sludge properties such as high total carbon and high C/N ratio of the initial compost mixes. Temperature in compost and ammonia emission were not greatly affected by the turning frequency.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.604-606
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• 1999

Solid animal wastes in Japan are treated mainly by composting. The composting process under controlled conditions is able to convert the wastes into high-quality organic fertilizer. Various types of composting facilities with/without forced aeration and turning device are available. Characterization of the maturing process during composting was studied, to improve the quality of compost and to make the degree of maturity. Recycling of animal wastes as compost without any environmental pollution will be closely related to the development of sustainable agriculture with organic fertilizer in Japan.

• Journal of Industrial Technology
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• v.13
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• pp.3-17
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• 1993

The composting process is a suitable to dispose the livestock manure in terms of resources recovery. However the performence of composting process is greatly affected by the environmental conditions such as characteristics of manure, type of the bulking agent, initial moisture contents, temperature, recycle and so on. The purpose of this study is to evaluate the optimum environmental conditions of composting process for livestock manures. The analytical results indicated that no bulking agent was necessary for the cow manure because of the proper C/N ratio. However the pig manure required a bulking agent since the pig manure had not only low in C/N ration but poor ventilation characteristics. In addtion, the initial miosture content for optimum composting appeared to be about 60%. The temperature control was also an essential factor to enhance the activity of thermophilic microorganisms in the laboratory composting unit. It was further found that the recycle of composts may contributed the completion of composting precess as well as C/N ratio reduction and moisture control.

• Journal of Animal Environmental Science
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• v.4 no.2
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• pp.149-160
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• 1998

Hog manure slurry amended with sawdust was composted in pilot-scale reactor vessels using continuous aeration nuder different C/N ratios and pH conditions during composting high rate (decomposition) process. For each material two replicated piles were built and monitored over a period of three weeks. The compost piles had an initial volume of 0.18 ㎥. In this study we evaluated the temperature in compost O2 and CO2 evolution, aeration rate, NH3 concentration etc. and investigated the stability of compost during composting high rate process. According to measured results, while the maximum NH3 concentration during composting high rate process. According to measured results, while the maximum NH3 concentration during composting high rate was in the range of 213 to 412 ppm on 5th day which was near the optimum C/N(22∼24) and pH(7.5∼7.9). And then, the NH3 concentration reduced to between 22∼26 ppm by 13th day. The maximum NH3 concentration for the lower C/N(18∼19) and pH value of 6 reached 574∼1,063 ppm by the 16th through 11th days and the NH3 concentration during continuous aerated composting high rate process, it was more important to manage NH3 gas so that compost odor is reduced.

• Journal of Animal Environmental Science
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• v.3 no.1
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• pp.13-18
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• 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 Environmental Health Sciences
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• v.26 no.3
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• pp.1-10
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• 2000

Although microorganisms play an important role in composting process, researches on the effective microorganism (EM) in composting process are rarely reported. In this study, three stages of work performed 1) investigation of composting facility 2) sample collection and isolation of the EM 3) lab-scale composting by seeding the isolated EM. For this, purpose, physical, chemical, and biological characteristics, such as temperature, moisture content, organic matter, pH population of microorganism, etc., were investigated during the process and the results were compared with those of a control(non-seeded). In the composting facility, the most active degradation of food waste was suppsed to occur in 10-11th day of composting by observing the temperature and CO2 emission. The population of bacterial and fungi was highest in thermophilic stage. Meanwhile that of actinomycetes and yeast was relatively uniform during the process. In the lab-scale test, the thermophilic stage was maintained longer(more than 9 days in 17 days of experiment) in the seeded which was favored for the high reduction of organic matter and moisture. Reduction rates of lipids and salinity were also increased in the seeded. It confirmed these results that the population of microorganisms in the seeded was observed higher in several orders than the control. However, pH of the seeded was maintained as low as about 4.5 throughout the experiment except the final period of the process. Meanwhile, pH of the control rose in the early stage of the experiment. This was probably due that the seeded microorganisms collected from the composting facility was adapted to the low pH environment.

• 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.21 no.2
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• pp.56-62
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• 2013

Organic wastes are not disposing object but renewable resources. One of those ways of rendering to resources, composting is environmentally friendly way as to aspect of recycling of resources. Regardless of ways, composting goes through the main processes which are fermentation process and curing process. In the study, mobile composting device was developed with the experiments which were performed to solve the problems of fermentation and curing process. Since reaction vessel is rotated, it does not cease in the middle of agitation because of foreign. In addition, it mixed as well. With maintaining uniform temperature of reaction vessel by controlling amount of air, fermentation and curing are easy to use. Its economic feasibility is better than the existing fermentation equipments. Furthermore, it benefits to reduce the personnel and materiel maintenance cost, and mass produce composting product which use organic waste. Especially, although it needs less space, it has effect to provide transferable composting device with available area to increase by contacting organic waste to air.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.900-905
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• 2009

We analyzed succession of the bacterial communities during composting of animal manure in three individual facilities. Polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) targeting for the bacterial 16S rRNA gene were used to clarify the changes of bacterial community throughout each composting process. Our study revealed that the bacterial community structures differed during the composting process. The bacterial community in composting of facility A showed little change throughout the process. In the compost sample from facility B, its community had a small shift as the temperature increased. In compost from facility C, the temperature dynamically changed; it was shown that various bacterial communities appeared and disappeared as follows: in the initial phase, the members of phylum Bacteroidetes dominated; in the thermophilic phase, some bacteria belonging to phylum Firmicutes increased; towards the end, the community structure consisted of three phyla, Bacteroidetes, Firmicutes, and Proteobacteria. This study provides some information about the bacterial community actually present in field-scale composting with animal manure.