关键词: 固定床, 低温慢速热解, 煤炭地下气化, 元素迁移规律, 热解产物

Abstract: During coal pyrolysis, a certain percentage of each element(C,H,O,N,S) will be transferred from raw coal into pyrolysis products, in this paper Dayan coal is heated at the atmosphere of N2 in the fixed bed at the low temperatures and heating rate in order to get the transferred ratio and then research the transferred law quantitatively, which can be applied in the stage of pyrolysis of UCG equilibrium model and predict the yields and components of the syngas and contaminants in the outlet hole. The results show that: when the end temperature of pyrolysis increases, the transferred ratios of each element in the ash and gasification carton decrease, but the ratios of the pyrolysis gas raise, the linear relationships exit between the end temperature and a(C,CH4/CO2/gasification C), a(H,CH4/H2), a(O,CO/CO2), a(N,HCN), a(S,COS), the changing rates for above are as follows: 0.0078%/℃, 0.0076%/℃, -0.0279%/℃,0.0571%/℃, 0.0528%/℃,0.0573%/℃, 0.0825%/℃,0.0087%/℃,0.0067%/℃；the maxima of the transferred ratios for each element (C, H,O,N,S) in tar turn up at 600 ℃,which are 10.36%、19.58%、4.03%、6.11%、6.30%；the maxima for each element (H,O) in pyrolysis water turn up at 700 ℃，which are 26.55%/℃,55.65%/℃.

Key words: Fixed bed, Low temperature and heating rate, UCG, Element transferred law, Pyrolysis produce