• 한국지하수토양환경학회지:지하수토양환경
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• 제21권3호
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• pp.14-20
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• 2016

Remediation of crude oil contaminated soil is complicate and hard to apply traditional methods because of its persistency, durability, and high viscosity. Therefore, in this study, the efficiency of crude oil contaminated soil remediation was tested by developing a pilot-scale thermal desorption system using the indirect heating method with an exhaust gas treatment. Under optimal condition drawed by temperature and retention time, the remedial efficiency of crude oil contaminated soil and treatability of exhaust gas were analyzed. Total Petroleum Hydrocarbon (TPH) concentration of crude oil contaminated soil was decreased to 69.7 mg/kg on average and the remedial efficiency was measured at 99.60%. Through the exhaust gas, 86.0% of Volatile Organic Compounds (VOC) was degraded and 97.16% of complex malodor was reduced under the suggested optimum operation condition. This study provides important basic data to be useful in scaling up of the indirect thermal desorption system for the remediation of crude oil contaminated soil.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.44-52
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• 2002

Low temperature thermal desorption (LTTD) has become one of the cornerstone technologies used for the treatment of contaminated soils and sediments in the United States. LTTD technology was first used in the mid-1980s for soil treatment on sites managed under the Comprehensive Environmental Respones, Compensation and Liability Act (CERCLA) or Superfund. Implementation was facilitated by CERCLA regulations that require only that spplicable regulations shall be met thus avoiding the need for protracted and expensive permit applications for thermal treatment equipment. The initial equipment designs used typically came from technology transfer sources. Asphalt manufacturing plants were converted to direct-fired LTTD systems, and conventional calciners were adapted for use as indirect-fired LTTD systems. Other innovative designs included hot sand recycle technology (initially developed for synfuels production from tar sand and oil shale), recycle sweep gas, travelling belts and batch-charged vacuum chambers, among others. These systems were used to treat soil contaminated with total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAHs), pesticides, polychlorinated biphenyls (PCBs) and dioxin with varying degrees of success. Ultimately, performance and cost considerations established the suite of systems that are used for LTTD soil treatment applications today. This paper briefly reviews the develpoment of LTTD systems and summarizes the design, performance and cost characteristics of the equipment in use today. Designs reviewed include continuous feed direct-fired and indirect-fired equipment, batch feed systems and in-situ equipment. Performance is compared in terms of before-and-after contaminant levels in the soil and permissible emissions levels in the stack gas vented to the atmosphere. The review of air emissions standards includes a review of regulations in the U.S. and the European Union (EU). Key cost centers for the mobilization and operation of LTTD equipment are identified and compared for the different types of LTTD systems in use today. A work chart is provided for the selection of the optmum LTTD system for site-specific applications. LTTD technology continues to be a cornerstone technology for soil treatment in the U.S. and elsewhere. Examples of leading-edge LTTD technologies developed in the U.S. that are now being delivered locally in global projects are described.

• 공업화학
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• 제1권2호
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• pp.215-223
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• 1990

자동차 배기가스 정화용 촉매계에서 중요하게 취급되는 CO와 NO의 산화환원반응에서 대표적인 촉매독으로 작용하는 황의 영향을 다결정 Pt 표면 위에서 초고진공계를 이용한 열탁착 분광법(TDS)을 통하여 알아보았다. Pt 표면에서의 CO와 NO의 흡착은 황에 의하여, 물리적인 흡착방해에 의한 직접적인 영향과 전자적 효과에 의한 간접적인 영향을 받았다. 800 K 이하의 온도에서 탈착하는 S는 반응활성에 큰 영향을 미치지 못하는 반면, 800 K 이상에서 탈착하는 S는 원자상태의 것으로서 반응활성에 직접적인 영향을 미쳤다. Pt 표면위에 흡착된 S는 island 형태로 존재하며, S에 의한 전자적인 영향은 주위의 모든 흡착점에 미치는 먼거리 상호작용의 경향을 나타내었다. 한편, Pt 표면에서의 CO와 NO의 반응에서 S에 의한 피독은 특정 활성점에 우선적으로 영향을 미치는 선택적인 경향을 보였다.