• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.272-275
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• 2005

본 실험은 염소계유해유기화합물을 처리하는 목적으로 종래의 초임계수산화법의 결점을 완전히 해결하기 위해서 도달한 것이 질산나트륨을 산화제로서 사용하는 개량된 초임계수 산화법(다단계산화법)이다. 이와 같이 본 연구팀이 개발한 개량된산화법(다단계산화법)은 매우 간단하며 저렴한 염소계유기물 분해처리시스템을 구축하는 것이 가능하다.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.173-176
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• 1999

The production of fine metal oxide particles in supercritical water has been studied. Cobalt nitrate solution and manganese nitrate solution have been selected as model solutions for metal salt aqueous solution and the particles of cobalt oxide and manganese oxide have been produced. It was observed that the production of fine metal oxide particles in supercritical water was feasible and the dehydration rate was remarkably high in supercritical water. In spite of a short residence time (3~100 seconds), fine particles ($0.5{\sim}2{\mu}m$) have been produced. In the supercritical water process, the temperature of mixer had a significant effect on particle size and size distribution. It was observed that a change in reaction temperature resulted in the control of particle size.

• Environmental engineer
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• s.177
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• pp.62-68
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• 2001

한화석유화학(주) 중앙연구소는 1994년부터 고농도 난분해성 및 독성폐수 처리에 99.9$\%$ 이상의 탁월한 COD 처리효과를 나타내는 초임계수 산화 기술을 순수 국내 기술로 개발하는 연구를 추진하여 왔다. 한화종합화학(주) 중앙연구소에서는 서강대학교와 한국화학연구소가 보유한 실험실 단계의 초임계 유체 기술과 SCWO 기술을 공동 연구를 통하여 5년 동안 자체적으로 기술 개발을 진행하였고, 제0585호 국산신기술인증(KT)을 받았으

• Korean Chemical Engineering Research
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• v.45 no.1
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• pp.46-51
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• 2007

In this study, computer simulations have been performed for the removal of the transformer oil contaminated with polychlorinated biphenyls (PCBs) in supercritical water through complete combustion reaction. We regarded n-decane as a main material of transformer oil, and it is assumed to be 3.0 wt％ of transformer oil in supercritical water. We used Peng-Robinson equation of state to estimate the physical properties of components in supercritical water. Throughout the computer simulation done in this work, we could explain the solubilities of 3.0 wt% of transformer oil and excess oxygen in supercritical water.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.318-323
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• 2005

Supercritical water oxidation (SCWO, P>221 bar, T>$374^{\circ}C$) is a promising method for the decomposition of refractory organic compounds. In this study, the SCWO of Ethylenediaminetetraacetic acid (EDTA) was carried out in a tubular-type continusous reactor system with an $H_2O_2$ oxidant at $387-500^{\circ}C$, 250 bar and residence time (RT) of 15.9-88.9 s. The decomposition efficiencies increased with increasing temperature and oxidant amount, while it was inversely proportional to feed flow rate. The decomposition efficiency of 99.6% was obtained at $500^{\circ}C$, 250 bar, oxidant amount of 400% and residence time of 40.1 s. The effect of temperature on the decomposition efficiency was more significant than that of oxidant amount. In the case of the decomposition efficiency of 5,000 mg/L of EDTA (3,063 mg/L as $COD_{Cr}$), the decompostion of 99% or higher was obtained at the condition of over 40.1 s (RT) and 200 stoichiometric % of $H_2O_2$ in the supercritical water of $500^{\circ}C$ and 250 bar.

• 기계와재료
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• v.13 no.1 s.47
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• pp.35-44
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• 2001

• 기계와재료
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• v.13 no.1 s.47
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• pp.17-27
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• 2001

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.636-643
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• 2006

Supercritical water oxidation of DMMP using continuous flow reactor was studied at temperature ranging from 440 to $540^{\circ}C$ and a fixed pressure of 242 bar. The range of residence times in the reactor was from 10 to 26 s, and oxygen excess value varied from -40 to 200%. Destruction efficiencies (DE) of DMMP were greater than 99.7% at $540^{\circ}C$, and increased as the DMMP concentrations were increased. DE of DMMP were significantly affected by oxygen concentration under stoichiometric amount, but showed little difference over stoichiometric amount. On the basis of 30 data with conversions greater than 85%, kinetic correlations for the DE of DMMP were developed. The pre-exponential factor was $(1.10{\pm}0.76){\times}10^6$, and the activation energy was $90.66{\pm}3.87kJ/mol$, and the reaction orders for DMMP and oxygen were $1.02{\pm}0.03$, $0.32{\pm}0.03$, respectively. The model predictions agreed well with the experimental data.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.78-82
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• 2003

For the decomposition of laundry wastewater containing Fe-EDTA produced from the steam generators in nuclear power plants, Supercritical Water Oxidation (SCWO) Process, Photocatalytic Oxidation (PO) Process, and Dielectric Barrier Discharge (DBD) Atmospheric Pressure Plasma Process were evaluated. Even though EDTA was converted over 99.98 % by the SCWO process, it was estimated that the countermeasure against corrosion of the equipment should be reinforced for the process stability. It was considered that the PO process is not appropriate for the decomposition of high concentrated laundry wastewater since the conversion ratio of EDTA was around 10 %. Finally, High efficiency of the decomposition of organic matter (methylene blue) was obtained using DBD process even low energy was supplied. However there is still room for the evaluation of EDTA decomposition in order that the DBD process should be applied for the field samples.

• 기계와재료
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• v.10 no.3 s.37
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• pp.63-70
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• 1998