贝壳和石灰石作为燃煤固硫剂的微观结构特性

引　言长期以来贝壳多作为垃圾被抛弃掉 ,将其作为燃煤固硫剂的设想早在 1995年的第三届国际煤燃烧会议上就由日本的Ｎａｒｕｓｅ等提出1] .他们的试验结果表明贝壳的钙利用率明显高于普通石灰石 ,85 0℃时贝壳的钙利用率是石灰石的 1 5倍 .为探讨贝壳钙利用率高的原因 ,本研究对贝壳与石灰石的微观结构特性进行了电镜实验分析 ,并利用ＬＣＴ 2型热天平和高温管式炉对其固硫反应能力进行了实验验证 ,以便为选择合适的燃煤固硫剂、改善固硫剂的钙利用率提供依据1　反应原理贝壳与石灰石的化学成分相近 ,其主要成分都是ＣａＣＯ3 ,所以它们的…

MICROSTRUCTURAL CHARACTERISTICS OF SHELL AND LIMESTONE AS BURNING COAL SULFUR SORBENT

The microstructure of the raw,calcined,and desulfurized sa mp les of shell and limestone was detected and analyzed by SEM.Their ability of ca pturing SO_2 was verified by using LCT-2 thermobalance and the high temperatur e tube reactor.The results showed that the better pore structure and smaller ga s diffusion resistance of shell were in favor of the inner reaction for SO_2 ga s.Shell had higher calcium utilization ratio than that of limestone especially under the conditions of high reaction temperature and the increased reaction tim e.The bigger difference of the inner structure was found in the reaction of sul fation after calcination and direct sulfation.In direct sulfation, the reaction was restrained because of the bad pore connectivity, while the former reaction took place with good pore connectivity.