兖州高硫煤的加氢热解脱硫及脱硫动力学

STUDY OF DESULFURIZATION AND ITS KINETICS IN HYDROPYROLYSIS OF YANZHOU BITUMINOUS COAL

在加压热天平上，考察了氢气和氮气气氛下高硫煤的热解脱硫。利用气相色谱在线分析研究了硫化氢气体的逸出规律。结果表明，加氢热解比氮气下的热解有着更显著的脱硫作用，脱硫率可达９０％以上。而且加氢热解下６５％的脱除硫转化为气相硫化氢，而氮气下热解则有８０％的硫转化为液相。两种气氛中硫化氢的逸出曲线都表现为两个峰，低温峰来源于脂肪族含硫化合物中硫的脱除，高温峰来源于硫铁矿和噻吩类含硫化合物中硫的脱除。动力学处理表明，对应于硫化氢的脱除峰，兖州煤的加氢热解和氮气下的热解脱硫过程宏观上可分为两段。采用简单的总包一级反应模型对脱硫动力学参数进行了计算。

Hydropyrolysis (HyPy) of Yanzhou bituminous coal was carried out in a pressurized thermobalance (CAHN: TG151) under pressures of 3 to 7MPa and temperatures ranging from 298 to 1073K The desulfurization yield was obtained from elemental analysis of residual char The volatile sulfide mainly H 2S was detected by an online gas chromatograph with a FPD detector As a comparison Pyrolysis(Py) in nitrogen atmosphere was also performed The hydrogen can greatly promote the effect of desulfurization and more than 90% sulfur in the coal can be removed About 65% of sulfur removed in HyPy was converted into H 2S and only 35% of sulfur entered into the liquid phase, while 80% of sulfur entered into the liquid in Py The releasing curves of H 2S in HyPy and Py process obviously showed two peaks The first peak at 350550℃ was from the desulfurization of aliphatic sulfide and the second peak at 550800℃ could be from both the sulfur in pyrite and aromatic thiophenic structure The kinetic parameters of desulfurization were determined by an overall firstorder reaction model The desulfurization process in HyPy and Py of Yanzhou bituminous coal can be regarded as in two stages according to the evolution profiles of H 2S The apparent energy of desulfurization in HyPy of Yanzhou coal under the two stages was about 110 and 140kJ/mol, respectively