煅烧石膏激发粉煤灰活性的机理研究

活性煅烧石膏分为两种类型 :经800℃左右煅烧产生的Ⅰ型煅烧石膏 ,以活性CaSO4 为主要成分 ;经1250℃左右煅烧产生的Ⅱ型煅烧石膏 ,以活性CaO和结构松驰的CaSO4 为主要成分。本文就煅烧石膏激发粉煤灰活性的机理探讨后认为 :Ⅱ型煅烧石膏初期为活性CaO对粉煤灰玻璃网络的解聚作用 ,后期为结构松驰的CaSO4 缓慢溶解产生的SO42 - 离子的硫酸盐激发作用 ,在碱度较高时 ,Al3 +呈[AlO4]形式与[SiO4]交叉连接 ,加速了胶凝材料中C -S -H形成 ,从而提高制品强度。

The active calcined plaster is divided into two types: Ⅰtype of calcined plaster via 800℃ calcination, taking active CaSO4 as main composition; Ⅱtype of calcined plaster via 1250℃ calcination, taking active CaO and loose structural CaSO4 as main composition. After probe into mechanism of calcined plaster activating fly ash, the author thinks thatⅡtype of calcined plaster is the active CaO to fly ash glass network depolymerization effect in initial stage, later is sulphate activation effect of SO42- ion produced from slowly dissolving of CaSO4, druing high alkalinity, Al3+ presents crossed connection of and , therefore, accelerating C-S-H formation in cementing material, thus increase product strength.