高碳粉煤灰超轻空心陶粒的制备

Preparation of High Carbon Fly Ash Ultralight Hollow Ceramsite

以高碳粉煤灰、凝灰岩和膨润土为主要原料,SiC 和 CaF2 分别作为发泡剂和助熔剂。原材料经磨细、筛选、混合、成球、晾干和高温焙烧等一系列程序后制成空心陶粒。用均匀试验法和单因素实验法探索原料用量、SiC 添加量、CaF2 添加量以及烧结温度对陶粒物理性能的影响。确定最优配比和最佳温度后,对陶粒的表观密度、抗压碎强度、吸水率和软化系数进行测试。此外,还利用 X 射线衍射仪对陶粒原料和成品进行物象分析。结果表明,当高碳粉煤灰∶膨润土∶凝灰岩=40∶ 15∶ 47. 5、碳化硅用量为0. 6%、氟化钙用量为0. 5%、烧结温度为1 300 ℃时,可获得空心陶粒;此时,陶粒的堆积密度为187 kg/m^3 ,筒压强度为 0. 204 MPa,24 h 吸水率为 1. 48%,软化系数为 0. 833。

High carbon fly ash,tuff and bentonite are used as main raw materials,SiC and CaF 2 are used as foaming agent and flux respectively. The raw materials are made into hollow ceramsite after a series of procedures such as grinding,screening,mixing,forming,drying and high temperature roasting. Uniform test method and sin- gle factor experiment method were used to explore the effects of raw material dosage,SiC addition,CaF 2 addition and sintering temperature on the physical properties of ceramsite. The apparent density,point strength,water ab- sorption and softening coefficient of the ceramsite are tested after the optimal ratio is determined. In addition,X-ray diffractometer is used to image the ceramsite raw materials and finished products. The results show that when high carbon fly ash∶ bentonite∶ tuff = 40∶ 15∶ 47. 5,the dosage of SiC is 0. 6%,the dosage of CaF 2 is 0. 5%,sintering temperature is 1 300 ℃,hollow ceramsite can be got;At this time,the ceramsite has a bulk density of 187 kg/m 3 , a cylinder compressive strength of 0. 204 MPa,a 24-hour water absorption rate of 1. 48%,and a softening coeffi- cient of 0. 833.