煅烧硬石膏溶解特性对钙矾石形成的影响  

Influence of Calcined Anhydrite Solubility on the Formation of Ettringite

作　　者：乔秀臣[1] 马大伟 薛玉兵 QIAO Xiuchen;MA Dawei;XUE Yubing(School of Resources and Environmental Engineering,East China University of Science and Technology,Shanghai 200237,China;Shanxi Jinneng Datuhe Thermal Power Co.,Ltd.,Shanxi,033000,China)

机构地区：[1]华东理工大学资源与环境工程学院,上海200237 [2]山西晋能大土河热电有限公司,山西033000

出　　处：《硅酸盐通报》2021年第1期201-206,共6页Bulletin of the Chinese Ceramic Society

摘　　要：本文依据循环流化床(CFB)锅炉干法脱硫温度条件,用煅烧硬石膏模拟干法脱硫产物,研究脱硫硬石膏性质对铝酸三钙(C 3A)反应生成钙矾石(AFt)的影响,探究CFB锅炉灰渣制备建材的可行性。结果表明:820℃、15 min形成的硬石膏,呈边棱清晰的板状晶体,而940℃、15 min形成的硬石膏晶体则发生烧结现象,高温导致硬石膏溶解性能降低。煅烧硬石膏与C 3A反应生成的AFt在养护3 d后达到最多,期间820℃形成的硬石膏以溶解沉淀方式生成针棒状AFt;而940℃形成的硬石膏则以固相反应方式生成团簇AFt。长期空气养护过程中的碳化反应会导致AFt分解。In this research anhydrite calcined under the dry desulphurization temperature of circulating fluid bed(CFB)boiler was used to simulate dry desulphurization product.The formation of ettringite(AFt)was investigated by curing the mixture of calcined anhydrite and tricalcium aluminate(C 3A).It was discussed in this research that the feasibility of preparing building materials using CFB ash.The results show that the anhydrite calcined at 820℃for 15 min is a plate-like crystal with sharp edges,and that calcined at 940℃for 15 min is partly sintered.High temperature prepared anhydrite shows lower solubility.The formation of AFt reaches the top after 3 d curing.During the period,the anhydrite formed at 820℃forms needle-shaped AFt by dissolving precipitation.While the anhydrite formed at 940℃forms agglomerates by solid phase reaction.The carbonization reaction during long-term air curing will cause the decomposition of AFt.

关 键 词：硬石膏 铝酸三钙 钙矾石 膨胀 脱硫 碳化 溶解特性 

分 类 号：TU526[建筑科学—建筑技术科学]