摘要
制备了磷石膏基免烧轻集料并测试了轻集料的相关性能,根据轻集料的表征分析其固化机理。当磷石膏掺量为54%时,表观密度最低为1277 kg/m3;掺量为51%时,堆积密度最低为953 kg/m3;掺量为45%时,21 d筒压强度最高为5.23 MPa,吸水率最低为25.5%。利用响应面模型分析粉煤灰、煅烧尾矿、生石灰配比对轻集料强度的影响,最优配比为m(粉煤灰)∶m(煅烧磷尾矿)∶m(生石灰)=23.53∶10.32∶2.88,此时预测21 d筒压强度为5.56 MPa,实际得到5.42 MPa,吸水率为24.5%,堆积密度为952 kg/m3,表观密度为1241 kg/m3的轻集料,对轻集料进行微观分析,发现板状磷石膏穿插胶凝在水化硅铝酸钙的地聚物网格中,针状钙矾石、钙沸石填充在孔隙中,各物料最终反应固化形成免烧轻集料。
In this paper,a new type of unfired light aggregate based on phosphogypsum was prepared and its properties were tested.The curing mechanism was analyzed according to the characterization of light aggregate.The minimum apparent density is 1277 kg/m3 when the content of phosphogypsum is 54%.The minimum bulk density is 953 kg/m3 when the content of phosphogypsum is 51%.When the content of phosphogypsum is 45%,the maximum 21 d cylinder compressive strength is 5.23 MPa,and the minimum water absorption is 25.5%.Response surface model was used to analyze the effects of fly ash,calcined tailings and quicklime on light aggregate compressive strength.Under the optimized conditions of m(fly ash)∶m(calcimed tailings)∶m(quicklime)=23.53∶10.32∶2.88,the 21-day compressive strength predicted by the system is 5.56 MPa.In fact,the 21-day compressive strength is 5.42 MPa.At the same time,the water absorption of light aggregate is 24.5%,the bulk density is 952 kg/m3,and the apparent density is 1241 kg/m3.Through microscopic analysis of light aggregate,it was observed that tabular phosphogypsum was inserted in the geopolymer grid of hydrated calcium aluminosilicate,acicular ettringite and calcium zeolite were filled in the pores.All material finally reacted and solidified to form unfired light aggregate.
作者
汪洋
李谋玉
樊晨阳
韦家斌
范旭阳
潘志权
WANG Yang;LI Mouyu;FAN Chenyang;WEI Jiabin;FAN Xuyang;PAN Zhiquan(School of Chemical and Environmental Engineering,Wuhan Institute of Technology,Wuhan 430205,China;Hubei Yangtze River Resources Recycling and Equipment Innovation Center Co.Ltd,Wuhan 430073,China;National Phosphorous Resources Development and Utilization of Engineering Technology Research Center,Wuhan Institute Of Technology,Wuhan 430060,China)
出处
《新型建筑材料》
2023年第8期84-88,共5页
New Building Materials
基金
湖北省技术创新专项重大项目(2018ACA154)。
关键词
磷石膏
免烧轻集料
激活
穿插胶凝
phosphogypsum
unfired light aggregate
activation
intercalate gelling
