• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.3
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• pp.35-43
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• 2011

In this study, anaerobic biological decomposition were attempted after solubilization treatment of sewage sludge with the complex pre-treatment (acid/base treatment with ultrasonic radiation). Solubilization ratios were compared for ultrasonic treatment at acid or base condition. Solubilization effect of the complex pre-treatment was more effective at higher pH. Biological decomposition of complex pre-treated sludge was faster than non treated (raw) sludge, showing 10 times higher total gas production. Biological digestion of the sludge shows more biogas production. B/A ratio. which indicates hydrogen production potential, was 50% higher with complex pre-treated sludge than raw sludge but lactic acid or propionic acid were also detected during anaerobic decomposition process.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.163-165
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• 2004

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.161-167
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• 2011

We previously showed that five strains belonging to Pseudomonas could remove TPH (Total Petroleum Hydrocarbons) efficiently when they are applied to TPH-contaminated soil. We optimized the bioremediation condition using different hydrocarbons and nutrients conditions to improve the efficiency. We setup lab-scale column bioreactor to monitor TPH and diesel removal efficiency. When we applied five Pseudomonas sp. mixtures to 25,000 $mg{\cdot}kg^{-1}$ TPH-contaminated soil (diesel 10,000 $mg{\cdot}kg^{-1}$, kerosene 10,000 $mg{\cdot}kg^{-1}$, gasoline 5,000 $mg{\cdot}kg^{-1}$) with the optimum condition, 76.3% of TPH removal efficiency was shown for 25 days. Meanwhile, in the application of five Pseudomonas sp. mixtures to 20,000 $mg{\cdot}kg^{-1}$ diesel-contaminated soil with the optimum condition, 99.2% of diesel removal efficiency was shown for 40 days. In the application to lab-scale bioreactor with five high efficiency bacteria, 88.5% of TPH removal efficiency was shown for 45 days. Based on the results from this study, we confirmed that this mixed Pseudomonas sp. consortium might improve the bioremediation of TPH in contaminated soil, the efficacy can be controlled by improving the nutrients. We also confirmed that the nutrients and oxygen for biodegradation of TPH could contribute on the management and control of applications of these strains for the study of bioremediation of TPH-contaminated soil.

• Journal of Life Science
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• v.33 no.1
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• pp.82-90
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• 2023

Biological process is used worldwide to treat domestic and industrial wastewater. The process generally uses a mixed microbial culture of sludge. The growth of microorganisms in the sludge produces excess sludge from the wastewater treatment process. Some of the excess sludge is recycled as inoculum for wastewater treatment, but the rest is removed as waste from the process. As wastewater production is increasing worldwide every year, the number of wastewater treatment plants (WWTPs) is also in- creasing, resulting in the generation of large amount of waste sludge. The increasing amount of waste sludge from WWTPs has led to concerns about its management. Sludge disposal has been reported to account for 50~60% of the total operating costs of a WWTP. Sludge disintegration is a new technology that can minimize volume of waste sludge and recover useful components (e.g., P, N, and soluble organic compounds) from it. Various methods of sludge disintegration have been developed based on physical, chemical, and biological treatments or combinations of these. In this review, we focus on sludge disintegration by acid hydrolysis, which is less studied among sludge disintegration methods. Such information can be useful in the development and implementation of a new technology for better sludge treatment.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.164-167
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• 2001

현장에서 채취한 토양을 이용하여 Microcosm test를 실시한 결과 온도 및 수분함량이 높을수록 BTEX 분해율이 증가하는 것으로 나타났으며 산소 농도는 21~32% 정도가 적당하였다. 그러나 BTEX 초기농도가 높은 경우에는 생분해율이 감소하는 것으로 나타났다. Bioventing 공법을 현장에 적용한 결과 OUR(Oxygen Utilization Rate)값은 6.3~16.3%O$_2$/day로 조사되었으며 Biodegradation rate 값은 3.4~8.8 mg hydrocarbon/kg soil/day로 조사되어 생물학적 처리 가능성이 있는 것으로 평가되었다.

• KSBB Journal
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• v.22 no.3
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• pp.157-161
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• 2007

This study is to investigate the biological degradation and the characteristics of MEA, a pH regulator to be put in the cooling water circulation system for power plants, loading to elevate concentrations of COD and N when eluted into the water environment. MEA, $NH_4^+$ and CODcr were monitored in flask cultures and in a batch aerator. MEA was found to be biologically degradable, producing substantial amount of ammonia (max. 78.1%) in a form of $NH_4^+$ and other carboneous intermediates. The degradation reaction rates were similar one another over all MEA concentrations tested as the activated sludge (microbial consortium) was acclimated to MEA with the gradual and stepwise increase in MEA input into the batch aerator. Also, MLVSS kept increasing with increasing MEA input. The COD-based degradation reaction order was determined to be 1.

• KSBB Journal
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• v.23 no.3
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• pp.245-250
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• 2008

The treatment of a model wastewater containing quinoline in an integrated wet oxidation-aerobic biological treatment was investigated. Partial wet oxidation under mild operating conditions was capable of converting the original quinoline to biodegradable organic acids such as nicotinic, formic and acetic acid, the solution of which was subjected to the subsequent aerobic biological treatment. The wet oxidation was carried out at 250$^{\circ}C$ and the initial pH of 7.0, and led to effluents of which nicotinic acid was oxidized through 6-hydroxynicotinic acid by a Bacillus species in the subsequent aerobic biological treatment. Either homogeneous catalyst of $CuSO_4$ or phenol, which is more degradable in the wet oxidation compared to quinoline, was also used for increasing the oxidation rate in the wet oxidation of quinoline at 200$^{\circ}C$. The oxidation of quinoline in the catalytic wet oxidation and the wet co-oxidation with phenol resulted in effluents of which nicotinic acid was biodegradable earlier in the aerobic biological treatment compared to those out of the non-catalytic wet oxidation at 250$^{\circ}C$. However, the lag phase in the biodegradation of nicotinic acid formed out of the wet oxidation at 250$^{\circ}C$ was considerably shortened after the adaptation of Bacillus species used in the aerobic biological treatment with the effluents of the quinoline wet oxidation.

• Environmental engineer
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• s.134
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• pp.16-21
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• 1997

• Environmental engineer
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• s.135
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• pp.14-18
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• 1997

• Environmental engineer
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• s.133
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• pp.8-13
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• 1997