白云石粉掺量和烧结温度对煤矸石轻骨料结构与性能的影响  

Effect of Dolomite Powder Content and Sintering Temperature on Structure and Properties of Coal Gangue Lightweight Aggregate

作　　者：孙鹏 王爱国[2] 吴宇[1] 孙道胜[2] SUN Peng;WANG Ai-guo;WU Yu;SUN Dao-sheng(Anhui Key Laboratory of Bridge and Tunnel Engineering Testing,Anhui Testing Center for Highway Engineering,Hefei 230051,China;Anhui Key Laboratory of Advanced Building Materials,Anhui Jianzhu University,Hefei 230022,China)

机构地区：[1]安徽省公路工程检测中心桥梁与隧道工程检测安徽省重点实验室,合肥230051 [2]安徽建筑大学,安徽省先进建筑材料重点实验室,合肥230022

出　　处：《硅酸盐通报》2019年第11期3580-3586,3596,共8页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(51308004,51778003);高校优秀中青年骨干人才国内外访学研修项目(gxfxZD2016134);安徽省高等教育人才项目(皖教高[2014]11号文)

摘　　要：以工业固体废弃物煤矸石为主要原料,白云石粉为发泡剂制备煤矸石轻骨料。研究了白云石粉掺量(4%、6%、8%、10%和12%)和烧结温度(1150℃、1200℃和1250℃)对煤矸石轻骨料矿物组成、孔隙率、表观密度、单颗粒抗压强度及内部孔结构的影响。结果表明:煤矸石轻骨料主要矿物成分为堇青石、莫来石、钙长石和石英。随着白云石粉掺量增大,煤矸石轻骨料的孔隙率和孔径逐渐增大,表观密度和单颗粒抗压强度逐渐减小,堇青石和钙长石含量增大,莫来石含量减小;随着烧结温度升高,煤矸石轻骨料的孔隙率和孔径逐渐增大,表观密度逐渐减小,堇青石含量增大。在1250℃下保温30 min,白云石粉掺量为10%时,制备煤矸石轻骨料的孔隙率达40.71%,表观密度为1528 kg/m^ 3,孔径为0.5~1.5 mm左右,颗粒抗压强度为5.76 MPa。白云石粉在轻骨料孔结构形成的过程中起到发泡组分和助熔组分的作用。在高温条件下白云石分解CO 2气体强烈向外逸出和适宜粘度液相对气体的抑制,二者协同作用实现轻骨料的膨胀过程。Coal gangue lightweight aggregate was prepared with industrial solid waste coal gangue as main raw material and dolomite powder as foaming agent.The influences of dolomite powder content(4%,6%,8%,10%,12%)and sintering temperature(1150℃,1200℃,1250℃)on the mineral compositions,porosity,apparent density,single particle compressive strength and internal pore structure of coal gangue lightweight aggregate(LWA)were investigated.The results show that the mineral compositions of coal gangue LWA are cordierite,mullite,anorthite and quartz.With the increase of dolomite powder content,the porosity and pore diameter of the coal gangue LWA increase,its apparent porosity and single particle compressive strength decrease gradually,and the content of cordierite and anorthite increase while content of mullite decreased.Similar to the influence of dolomite powder content,the porosity,pore diameter,apparent density and cordierite content of LWA have similar changes when sintering temperature increase.The coal gangue LWA with porosity of 40.71%,apparent density of 1528 kg/m ^3,pore diameter of 0.5-1.5 mm,single particle compressive strength of 5.76 MPa are prepared with dolomite powder content of 10%and sintering temperature of 1250℃for 30 min.Dolomite powder play the role of foaming component and assisting component in the formation of pore structure for LWA.Under the condition of high temperature,both the decomposition of CO 2 gas from dolomite and the inhibition of suitable viscosity liquid phase on the gas can realize the expansion process of LWA.

关 键 词：轻骨料 煤矸石 白云石粉 矿物组成 孔隙率 

分 类 号：TU528.041[建筑科学—建筑技术科学]