Fe_2O_3对小龙潭褐煤热解过程中硫迁移和转化特性的影响

Effect of Fe_2O_3 on transformation and migration of sulfur in Xiaolongtan lignite during pyrolysis

为了分析Fe_2O_3对煤热解过程中硫迁移特性的影响,在慢速升温固定床反应装置上分别开展了小龙潭原煤以及添加质量分数为5%Fe_2O_3的煤样在热解过程中硫的迁移和转化特性的实验研究。结果表明:Fe_2O_3会与煤气中H_2S发生固硫反应,使得煤气中的大部分硫以FeS_x的形式固定在半焦中,从而明显降低了H_2S的逸出量并增加了硫化物硫的生成量;添加Fe_2O_3可以降低焦油中硫的析出;Fe_2O_3在整个热解温度范围内都促进了硫酸盐硫的分解,表明Fe_2O_3可以同时促进硫酸铁和硫酸钙的分解;Fe_2O_3的添加促进了有机硫的脱除。

To study the effects of Fe2O3on transformation characteristics of sulfur during coal pyrolysis,the pyrolysis experiments for Xiaolongtan(XLT)raw coal and its mixture adding5%(mass proportion)Fe2O3were carried out in a fixed bed reactor.The results show that,Fe2O3reacted with H2S in the coal gas,thus most sulfur in the coal gas was fixed in the semi-coke in form of FeSx,thereby the release amount of H2S reduced significantly and sulfide sulfur in char increased.Adding Fe2O3in the coal prevented precipitation of sulfur from tar.In addition,Fe2O3promoted the decomposition of sulfate sulfur in the whole pyrolysis temperature range,which indicated that Fe2O3could promote the decomposition of ferric sulfate and calcium sulfate at the same time.The addition of Fe2O3promoted the removal of organic sulfur.