准东煤燃烧过程中钙硅镁分子动力学研究

Molecular Dynamics Research on the Interaction of Calcium,Silicon and Magnesium During the Combustion of Zhundong Coal

针对新疆高钙准东煤燃烧过程中钙镁黄长石的形成会影响准东煤结渣的问题,通过分子动力学方法对不同温度和矿物质配比下钙镁黄长石形成前的2个过程(CaO与SiO_(2)的结合过程和CaSiO_(3)与MgO的结合过程)进行探讨,计算分子之间的结合能和扩散系数,研究反应过程中矿物质的结合和扩散特性。结果表明:温度对CaO在SiO_(2)表面以及MgO在CaSiO_(3)表面结合特性的影响并不明显,但是对二者的扩散具有重要影响;随着温度的升高,CaO在SiO_(2)表面的扩散系数以及MgO在CaSiO_(3)表面的扩散系数均逐渐增大,高温下更易于形成钙镁黄长石。

Aiming at the problem that the formation of akermanite could affect the slagging of Xinjiang Zhundong high-calcium coal during the combustion process,based on molecular dynamics method,the two processes before the formation of akermanite at different temperatures and ratios of minerals were discussed,such as the combination process of CaO and SiO_(2)and the combination process of CaSiO_(3)and MgO.By calculating the binding energy and diffusion coefficient between different molecules,the binding and diffusion characteristics of these minerals were studied in the reaction process.Results show that the temperature has no obvious influence on the binding characteristics of CaO on the surface of SiO_(2)and MgO on the surface of CaSiO_(3),but has an important influence on their diffusion.With the increase of the temperature,the diffusion coefficient of CaO on the surface of SiO_(2)and the diffusion coefficient of MgO on the surface of CaSiO_(3)gradually increase,which indicates that it is easier to form akermanite at high temperatures.