Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Comparison of Counter-Current Cooling and Pool Boiling System Through Modeling and Simulation of a Pilot-Scale Fixed bed Reactor for Dimethyl Ether(DME) Synthesis

Dimethyl Ether(DME) 합성을 위한 파일럿 규모의 고정층 반응기의 모델링과 모사를 통한 향류 냉각방식과 포화액체 풀비등 방식의 비교

  • Song, Daesung (School of Chemical Engineering, Seoul National University) ;
  • Go, Jae Wook (Department of Chemical and Biological Engineering, Kwangwoon National Univesity) ;
  • Yoon, En Sup (School of Chemical Engineering, Seoul National University)
  • 송대성 (서울대학교 화학생물공학부) ;
  • 고재욱 (광운대학교 화학공학과) ;
  • 윤인섭 (서울대학교 화학생물공학부)
  • Received : 2009.06.09
  • Accepted : 2009.06.23
  • Published : 2009.08.31
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Abstract

The behavior of a one-step fixed bed reactor which directly synthesizes dimethyl ether(DME) from Natural Gas was simulated. In the reactor, the prevention of the occurrence of hot spots which can cause deactivation of catalysts is pivotal, since methanol synthesis and dehydration reaction involved in the synthesis of DME are highly exothermic. Therefore, we simulated and compared performance of the reactor with counter-current cooling and pool boiling system that can be applied to a commercial plant. As a result, we found that counter-current cooling system is more effective in terms of CO conversion and DME productivity. However, pool boiling system can operate in a small temperature gradient that can decrease problems caused by hot spot. And, the system can operate in a safer range.

최근 청정대체에너지로 각광을 받고 있는 dimethyl ether(DME)를 천연가스를 이용하여 직접 생산하는 1단계법의 고정층 촉매 반응기를 모사하였다. 1단계법의 고정층 반응기의 경우, 발열 반응인 메탄올 합성반응과 메탄올 탈수 반응이 동시에 일어나기 때문에 촉매의 비활성화를 일으킬 수 있는 hot spot의 발생을 막는 것이 가장 중요하다. 따라서 향후 상용공정에 적용 가능한 향류 냉각방식(count-current cooling system)과 포화액체 풀비등 방식(pool boiling system)을 적용하여 반응기 거동을 모사하고 이를 비교하였다. CO 전환율과 DME 생산성 면에서 향류 냉각방식이 더 효과적이었다. 하지만 포화비등액체 풀비등 방식이 더 작은 온도 범위에서 운전되어 hot spot(국소 고온점)의 가능성을 낮추고 더 안정적인 반응기 운전범위를 확보할 수 있었다.

Keywords

Acknowledgement

Supported by : 지식경제부

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