• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.1
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• pp.120-127
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• 2002

This study was carried out to evaluate the effects of initial concentration on composting of diesel-contaminated soil. Silt loam was used in this study. Target contaminant, diesel oil, was spiked at about 2,000, 4,000, and 10,000mg/kg of dry soil, respectively. Mix ratio of soil to sludge was 1:0.3 as wet weight basis. Temperature was maintained at $20^{\circ}C$ Volatilization loss of TPH was 0.7-3.5% of the initial concentrations. Volatilization loss of TPH was not increased in proportion to the initial concentration. After 30 days of operation, 86% and 94% of the initial concentrations at about 2,000 and 10,000mg TPH/kg were biodegraded. Normal alkanes were degraded more rapidly than TPH. The compounds of C12 to C14 were volatilized greatly among n-alkanes. The first order degradation rate constants of about 2,000, 4,000, and 10,000mg TPH/kg were 0.079, 0.069, and 0.061/day, respectively. Produced-$CO_2$ and degraded-TPH were correlated highly regardless of the initial TPH concentration(r = 0.97-0.99).

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.3
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• pp.77-87
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• 2001

Composting is a cost-effective and environmentally-sound technology to treat soils contaminated with hazardous organic pollutants. Pollutants to be treated are as follows: explosives, phenolic compounds, PAHs, petroleum hydrocarbons, pesticides, and etc. Composting systems are windrow, static pile, and in-vessel. Design and operational parameters of composting are aeration modes, temperature, moisture content, nutrient supplement, amendment added, and etc. Appropriate oxygen concentration of composting for contaminated soils are 5~15%, while some compounds are degraded well at the low $O_2$ concentration of 2~5%. The most diverse microorganisms live in the temperature of $25{\sim}40^{\circ}$. 50~90% of the soil field capacity is the moisture content not to make a problem in composting. Assuming a bacterial chemical equation is $C_{60}H_{87}O_{23}N_{12}P$, theoretical C : N : P from bacterial chemical portion is approximately 20 : 5 : 1. It should be noted that the ratio does not apply to the total organic carbon measured in a waste because not all carbon metabolized by bacteria is synthesized to new cellular material. Initial C/N ratio of 25~40 is optimum. It is more economical to recycle soils or composts than to add commercial microbes.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.132-139
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• 2002

This study was carried out to investigate the effects of aging and soil texture on composting of diesel-contaminated soil. The soils used for this study were silt loam and sand. Target contaminant, diesel oil, was spiked at 10,000mgTPH/kg of dry soil. Aging times of diesel-contaminated soils were 15days and 60days, respectively. Fresh diesel-contaminated soil was also investigated. Moisture content was controlled to 70% of soil field capacity. Mix ratio of soil to sludge was 1:0.3 as wet weight basis. Temperature was maintained at $20^{\circ}C$ Volatilization loss of TPH was below 2% of initial concentration. n-Alkanes lost by volatilization were mainly by the compounds of C10 to C17. Diesel in contaminated soil was mainly removed by biodegradation mechanism. First order degradation rate constant of TPH in sandy soil was ranged from 0.081 to 0.094/day, which is higher than that in silt loam(0.056-0.061/day). From fresh to 60day-aged soils, there was little difference of TPH biodegradation rate between the soils. Carbon recovery ranged from 0.61 to 0.89. TPH degradation rate was highly correlated with $CO_2$ production rate.

• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.204-214
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• 2013

This research was performed to evaluate Vibrio fischeri toxicity for TNT-contaminated soils treated by composting and slurry phase bioreactor, which were operated for 45 and 200 days, respectively. In case of composting, the GL value of acetone-added soil was 40, which was lower than th at of glucose-added soil after treatment. In case of slurry phase bioreactors under anaerobic, anaerobic/aerobic, and aerobic regimes, they showed the GL values of 6, 8, and 4 after treatment, respectively. It was evaluated that the toxicity of all slurry phase bioreactors was reduced significantly to detoxification. The relationships between GL value and the number of S. typhimurium in both composting and slurry phase bioreactor were developed as the first order equations with high correlation coefficient (r > 0.8890).

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.04a
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• pp.24-25
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• 1999

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.35-41
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• 2002

This study was conducted to evaluate the effect of initial concentration on pilot-scale composting of diesel-con-laminated soil. Sandy soi] was used in this study. Target contaminant, diesel oil, was spiked. at about 10,000, 25,000, and 50,000 mg TPH/kg of dry roil. Mit ratio of soil to sludge was 1:0.5 as wet weight basis. Removal efficiencies for initial concentrations of 12,966,23,894 and 51,042 mg TPH/kg were 90, 93 and 54％, respectively, during 33 days of composting. Normal alkanes in TPH ranged from 15 to 22％ in initial soils. Volatilization of individual normal alkane in 1,999 mg n-alkanes/kgwas completed within 4 days, while n-alkane compounds of Cl1-Cl4 in 5,270 and 9,836 mg n-alkanes/kg were volatilized continuously during 33 days of composing operation. The first order degradation rate con-stants for 12,966, 23,894, and 51,042 mg TPH/kg were 0.058, 0.076, and 0.022/day, and those for 1,997 5,270, and 9,836 mg n-alkanes/kg were 0.093, 0.100, and 0.019/day, respectively. Considering TPH removal rate, $CO_2$porduction rate, and dehydrogenase activity, the concentration of 51,042 mg TPH/kg inhibited biodegradation of diesel-composting.