바이오메스 혼합연료의 습윤 촉매 가스화 연구

Catalytic Wet Gasification of Biomass Mixed Fuels

  • 투고 : 2009.06.13
  • 심사 : 2009.06.25
  • 발행 : 2009.06.30

초록

하수슬러지를 에너지 열원으로 사용하기 위해서는 연료로서 청정해야 하고 따라서 수슬러지 중에 중금속이나 불순물이 없거나 미량이어야 한다. SOCA(Sludge-Oil- Coal-Agglomerates) 연료는 이러한 요구를 만족시키며, 고체 연료로서의 SOCA는 청정에너지를 생산하기 위해 가스화될 수 있다. 습윤 촉매가스화는 수분을 포함하는 SOCA에 대해 적절한 공정인 것으로 나타났다. 그러나 SOCA 연료 제조시 석탄이 사용됨에 따라, 촉매가스화 공정에서 촉매를 피독시킬 수 있는 황 성분이 SOCA 연료에 약 40~50% 정도 포함된다. 따라서, 가스화를 위한 적절한 촉매를 사용하는 것이 중요하다. 본 연구 결과에서는 칼슘이 SOCA의 가스화에 이상적인 촉매로 선택되었다. 또한 최적의 가스화는 적절한 수분을 공급하였을 때, $850^{\circ}C$에서 이루어지는 것으로 나타났다. 연료에 포함된 질소 성분은 궁극적으로 SOCA의 가스화에 중요한 역할을 하는 것으로 나타났다. 그 결과 가스화는 HCN의 발생을 최소화하고 $N_2$$NH_3$로의 전환을 향상시키는 방향으로 운전되어야 한다.

In order to utilize sewage sludge as a heat source of energy, it goes without saying that the fuel should be clean and pose no threat to the environment. As a consequent, it should not contain even minute quantities of heavy metals / impurities. The SOCA (Sludge-Oil-Coal- Agglomerates) fuel can meet all these requirements. SOCA being a solid fuel can be gasified for the production of clean energy. Wet catalytic gasification is the most appropriate process for SOCA containing nearly 60% water. It is important to note that the SOCA thus obtained inherits ca. 40~50% of sulfur from the coal used. It can poison the catalyst during catalytic gasification process. Consequently, it becomes important to choose a proper catalyst for the gasification. Calcium was found to be ideal choice as a catalyst for the gasification of SOCA. The optimal gasification was performed at $850^{\circ}C$ with water vapor. The role of fuel-N is of utmost importance in the gasification of SOCA. The gasification should be controlled to reduce the production of HCN to a minimum and enhance its conversion to $N_2$ and/or $NH_3$.

키워드

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