文献类型：期刊文献

英文题名：Exploring influence of MgO/SiO2 on viscosity-temperature property of coal ash slags under entrained flow gasification condition

作者：Li, Meng[1];Wu, Hao[1];Xu, Jianliang[1];Yu, Guangsuo[1,2];Chen, Xueli[1]

机构：[1]East China Univ Sci & Technol, Inst Clean Coal Technol, Shanghai 200237, Peoples R China;[2]Ningxia Univ, State Key Lab High Efficiency Utilizat Coal & Gree, Yinchuan 750021, Ningxia, Peoples R China

年份：2023

卷号：284

外文期刊名：ENERGY

收录：;EI(收录号：20234114854566);WOS:【SCI-EXPANDED(收录号:WOS:001091729300001)】；

基金：This research was financially supported by the National Natural Science Foundation of China (21878082+) .

语种：英文

外文关键词：Viscosity -temperature characteristics; Slag discharge; Slags; MgO/SiO2

摘要：To realize smooth slag discharge of Zhundong coals in entrained-flow-bed gasifier, the viscosity-temperature characteristics of slags with different MgO/SiO2 ratios were studied. The results show that low MgO/SiO2 ratio causes high BO content in liquid slag, resulting in excessive polymerization degree and viscosity. As the MgO/SiO2 increases, the activation energy of liquid slag increases, occurrence form of oxygen transforms from BO to NBO, more structural depolymerization reactions occur, and [SiO4] tetrahedra obtains more O2-and show more NBO. NBO is more likely to react with Mg2+, Ca2+, Al3+, and Fe2+ to form crystals, thus increasing the crystallization reaction activity of slag and cause the initial crystallization temperature and crystal content increasing. An increasing MgO/SiO2 causes a characteristic transition of slag from weak crystallinity and high polymerization degree to strong crystallinity and low polymerization degree, meanwhile, the poor viscosity -temperature characteristics with high viscosity of liquid slag is first improved, and then the problem of strong crystallinity leading to poor viscosity-temperature characteristics with high Tcv occurs. Therefore, the viscosity -temperature characteristics first improve and then deteriorate. The crystal size increases as MgO/SiO2 increases, which also cause Tcv increasing. Large Delta T and low Tp25 make 0.28MS become the most suitable for slag discharge.