不同催化剂对准东煤的催化气化特性对比研究

Contrast research on catalytic gasification characteristics of different catalysts on Zhundong Coal

为掌握低温750℃条件下准东煤的催化气化特性规律,采用差示扫描量热与热重分析仪,通过确定适宜的CO_2气体流量、煤焦质量和颗粒直径,研究分析了准东煤在低温、微量催化剂及其不同加载方式下的催化气化特性。结果表明:低温下,准东煤在微量催化剂条件下完成催化气化过程,催化剂添加量增加,反应速率加快,催化效果更强;催化剂加载方式不同,催化效果不同,对Ca(OH)_2而言,催化效果高温高压法>浸渍法>研磨法;对K_2CO_3而言,催化效果研磨法>高温高压法>浸渍法;相同加载方式条件下,当催化剂添加量小于1.70%(质量分数)时,Ca(OH)_2催化效果优于K_2CO_3;当催化剂添加量大于3.20%时,Ca(OH)_2催化效果弱于K_2CO_3,这很可能与煤中的活性位点等因素有关。

In order to understand the rule of catalytic gasification characteristics of Zhundong Coal at the low temperature of 750 ℃,based on the determination of the appropriate CO_2 gas flow,coke mass and particle diameter,the differential scanning calorimetry and thermogravimetric analyzer were used to analyze the gasification characteristics of Zhundong Coal with slight catalyst at low temperature under different loading modes. The experimental results showed that Zhundong Coal finished gasification at low temperature under the action of trace amounts of catalyst,and with the increase of catalyst,the reaction rate was accelerated and the catalytic effect was stronger. The different catalyst loading modes caused different catalytic effect,for calcium hydroxide,catalytic effect from strong to weak as follows,high temperature and high pressure method was the best,immersion method was worse,grinding method was the worst; for potash,grinding method was the best,high temperature and high pressure method was worse,immersion method was the worst. With the same catalyst loading mode,when the catalyst mass fraction was less than 1. 70%,calcium hydroxide was better than potash,while potash was better than calcium hydroxide when the catalyst mass fraction was less than 3.20%,it was probably related to such factors as the active sites of coal.