煤的水蒸气等离子体气化初步研究

Trial study of coal gasification under steam plasma conditions

煤的水蒸气等离子体气化技术是一种生产合成气的洁净煤技术,具有潜在的应用前景,其技术核心部分是电弧等离子体反应器.以水蒸气为气化介质、空气为输送介质,对煤在电弧等离子体中的气化行为进行了研究;所用等离子体反应器由石墨管阳极和石墨棒阴极构成;反应器内的等离子体通过外置线圈产生的磁场进行约束和控制.结果表明:合成气中有效气体(H2+CO)的体积分数随着磁场线圈电流的增大或者等离子体反应器输入功率的增加而提高,产品气体中H2+CO的体积分数可达到75%,而CO2的体积分数始终低于3%,在产品气体中未检测到甲烷.

Coal gasification in steam medium under plasma conditions is a promising technology for clean utilization of coal, of which the central part is the plasma generator. A tube-like arc plasma setup was built with an aim of studying the possibility and the feasibility of coal gasification in the medium of steam and/or air. In the arc plasma generator, a graphite tube (i.d. 150 mm) was made as the anode and a graphite rod of φ30×1 000 mm was made as the cathode. An electromagnetic coil was put outside the plasma generator, which functioned to confine the arc plasma and to make it swirl inside the generator. One bituminous coal was gasified in steam medium with air as carrier gas under plasma conditions. The results show that the content of (CO+H_2) in the product gas increases with the increasing of coil current or input power, which could reach 75% (volume fraction) with CO_2 being less than 3.0%, no methane was detected in the gas. The obtained gas can be used as synthesis gas.