铁硅系添加剂对型煤燃烧时硫行为的影响

利用扫描电镜（ＳＥＭ）、能谱分析（ＥＤＡＸ）和Ｘ射线衍射分析等现代物理分析技术，从形态、化学组成和结构三方面入手，研究了型煤燃烧时，添加铁、硅、锶等以钙为主的几种固硫剂后，灰渣的物相变化及硫的走向，结果表明，钙系化合物的型煤燃烧时，煤中的硫以硫酸钙的形式进入渣中，硫酸钙被高融点硅酸盐矿物所包裹是高温下硫酸钙不易分解的重要原因，添加少量碳酸锶的钙系固硫剂，硫元素除了形成硫酸钼和硫酸锶以外，还形成了一

EFFECT OF Fe2O3-SiO2 IN CALCIUM SYSTEM ADDITIVES ON BEHAVIOR OF SULPHUR IN BURNING COAL BRIQUETS

The phase change and the distribution of sulphur in residues of coal briquet with sulphur-fixing-agents containing compunds of calcium,iron,silicon,and strontium have been studied by examining the monography,chemical composition and structure by SEM, EDAX and XRD techniques.It was showed that sulphur existed in residues mainly as calcium sulphate,which was covered with a film of silicates. the silicates possessing high melting points could prevent from decomposition of calcium sulphate up to a very high temperature. When the additive contained a small amount of strontium carbonate, a new phase in residues with a composition of 3CaO · 3Al₂O₃· CaSO₄ was formed along with calcium sulphate and strontium sulphate. This new composed phase was stable at high temperature,therefore,the effectiveness of fixation of sulphur was increased.Addition of ferric oxide and silica to the calcium system sulphur-fixed-agent,ferric oxide not only directly participated in fixing of sulphur, but also reacted synergetically with silica, and made silica easier to form silicate film around contained phases to be stabilized at high temperature, and eventually increased the effectiveness of the fixation of sulphur in the residue.