• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.2
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• pp.72-81
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• 2004

For disposal food wastes which is about 30% portion of tatal organic wastes, vermicomposting is more environmental-friendly treatment than lanfill, incineration, etc. Recently, the interest has been increasing but there are many problems on management of vermicopmposting in field especially. This study was conducted to investigate an optimal factors, which are limit NaCl conc., the mixing rate of food wastes and casting for growth of an earthworm related to efficient vermicomposting. The limit conc. of NaCl was 0.5% and in case of feeding food wastes to earthworms as a prey only, most earthworms were dead in a few hours due to excessive degradation of organic materials and high NaCl conc. However as feeding with the casting of proper mixing rate(3:7), most earthworms were survived until finishing composting. It was investigated the increaser degree of matureness of food wastes, the higher conc. of NaCl, therefore for efficient vermicomposting, it seemed proper mixing rate of food wastes and the casting is better than matureness of food wastes. and the most suitable mixing rate was 3:7 food wastes and the casting.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.89-98
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• 2001

Present vermicomposting technology needs the broad land. Because of the high land cost, the land saving technology such as multistage must be needed. And present operation practices are mostly based on human power, mechanization and automation is needed. Also, present control practices based on individual experience need the scientific base control system. Even though the rough estimation of organic waste treatment showed that vermicompostiong could obtain more benefits than costs. But, the estimation is based on an ideal case without considering the technical and market. Generally, vermicomposting is considered as the more expensive technology than composting. Therefore, the practical proof the economic factor would be the most important to the market increase. Vermicomposting as the recycling technology has better condition than incineration and landfill. Propagation and advocating focused on its environmentally sound aspects would be needed continuously. Especially, demonstration and distribution of household vermicomposting would be a good approach. Vermicomposting facilities area was becoming larger, and earthworm feeding materials were also expanding to various organic sludges. These trends showed that vermicomposting is being enlightened to treat and recycle the organic wastes.

• Journal of the Korea Organic Resources Recycling Association
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• v.1 no.1
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• pp.85-102
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• 1993

This study was conducted to achieve develop organic sludge recycling technology as sludge make a prey of earthworm. Therefore sludge treatment and recycling technology is an important field by which this research project to solve landfill site and reduction treatment expense using vermicomposting treatment process on the waste sludge from the biological wastewater treatment plant. In experimental results on the optimum conditions of vermicomposting of nightsoil treatment sludge, survival rates were observed 98.3% in temperature of $10-15^{\circ}C$, 75% in pH 5.8-7.5 and 100% in density of $1/79.8cm^3$, respectively. Liveweight changes of earthworm were increased 266% in temperature of $10-15^{\circ}C$, 227% in pH 5.8-7.5 and 325 % in density $1\;cap./79.8cm^3$, respectively. Casting production rate were generated 0.06 g/cap./day in temperature $20-25^{\circ}C$, 0.065 g/cap./day in pH 5.8-7.5 and 0.1 g/cap./day in density $1\;cap./79.8cm^3$, respectively. Cocoon production numbers were observed 3.8 ea. /cap.in $10-15^{\circ}C$, 2.95 ea./cap.in pH 5.8-7.5 and 3.16 ea./cap. in $1\;cap./79.8cm^3$ during 6 weeks, respectively. pH was droped by 6.2 to 5.7, volatile solids was decreased by 2.9%, $NH_3-N$ were also reduced by $6.984{\mu}g/g$ to $0.991{\mu}g/g$. $NO_3-N$, however, were increased by $3.213{\mu}g/g$ to $7.706{\mu}g/g$. Fecal coliforms and pathogenic bacteria are analyzed by microbiological method to assess public health safety of casting. Number of fecal coliform groups were reduced 88.6-99.1% (Avg. 95.7%) approximately. And pathogenic bacteria such as Salmonella, Shiegella and Vibrio, were not isolated from the earthworm cast.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.4
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• pp.72-86
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• 2014

This study was conducted to investigate the effects of mulching of easily-decomposable organic materials including rice powder and corn starch on rice paddy fields. The treatments were including seven mulching materials each consisted of rice powder [Rice], starch with black color [Starch-B] and transparent [Starch-T] and stone powder [Stone], and conventional vinyl [Conventional], no-mulching without herbicide [Control-O] and no-mulching with herbicide [Control-C]. Rice growth and yield were different among the treatments; the highest yields were observed for [Rice] ($6.51ton\;ha^{-1}$) and [Conventional] ($6.47ton\;ha^{-1}$) followed by [Starch-T] ($6.25ton\;ha^{-1}$) and [Stone] ($6.20ton\;ha^{-1}$) which is comparable to the [Control-C] ($6.15ton\;ha^{-1}$). However, [Starch-B] showed lower rice yield ($4.93ton\;ha^{-1}$) than the [Conventional] or [Control-C]. Mean soil temperature ranged form 23.6 to $24.1^{\circ}C$ with the highest temperature for [Rice] treatment, and cumulative soil temperature was also significantly higher in the [Rice] treatment. Among the soil parameters, electrical conductivity, organic matter content, and phosphorus concentration were also different among the treatments. The amount of earthworm casting was higher for [Rice] treatment ($17.7kg\;m^{-2}$) compared to the others ($5.5{\sim}9.8kg\;m^{-2}$). It was suggested that mulching of rice fields with organic materials containing rice powder is better than others in respected to rice yield and earthworm activity.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.35-41
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• 2003

The on-site sewage sludge vermicomposting equipment was designed and evaluated on the batch and continuous tests. The vermicomposting equipment was designed to consider the mechanization as well as automation. Especially, the automatic controls of water content and temperature and the mechanization of the sludge feeding and cast separating were the important factors. In terms of changes in chemical characteristics when the equipments for experiments are operated continuously, the ORP, EC, $NH_3-N$ and $NO_3-N$ were found to be higher before and after treatment. In addition, it was found that changes in properties were low. Furthermore, the $NO_3-N$ concentration of the humus produced after treatment was found to be higher than the $NH_3-N$ concentration showing that it was appropriate based on the recycling criteria.