No.15 石炭ガス化における気相析出炭素生成・反応挙動(研究発表)

抄録

In coal gasification, two carbon solids are generated. At first, volatile matter and solid char are generated through coal pyrolysis. After that, volatile matter decomposes and partially precipitates as solid soot or coke. The soot produced through coal pyrolysis in inert gas has lower gasification reactivity than char. It is necessary to clarify the soot production and reaction behavior in coal gasification condition, aiming at the improvement of the carbon conversion in coal gasifying process. However, there had been no proper deliberation of soot quantitative method because the char and the soot are mixed together and are difficult to separate. CRIEPI has proposed a new handy and reliable soot quantitative method using a laser diffraction particle size analyzer. In this study, using pressurized drop tube furnace (PDTF), coal gasification experiment was performed. As a result, in CO_2 gasification condition, the yield of soot with low gasification reactivity did not decrease while char yield decreased as CO_2 concentration increased. Furthermore, in O_2 gasification condition, the soot yield decreased greatly because the volatile matter reacted with O_2.