燃准东煤过程中含钙矿物质对沉积初始层形成影响研究

Study on the Influence of Calcium-bearing Minerals on the Formation of Sedimentary Initial Layer during the Process of Zhundong Coal Combustion

准东煤作为一种良好的动力用煤,在燃烧过程中极易出现结渣、沾污问题。煤中高含量的钙是引起灰沉积现象严重的重要原因。本文利用分子动力学计算含钙矿物质在氧化膜孔径中的扩散及结合特性。结果表明,随着氧化膜孔径增加,含钙矿物质运动更加剧烈且反应活性增强。大孔径下含钙矿物质更易填充到氧化膜孔隙,孔径在4nm时,CaO与CaSO4更易填充到孔隙中。CaSO4更易与α-Fe2O3反应CaSO4先粘附于壁面上。

As a good power coal,Zhundong coal is prone to slagging and contamination during the combustion process.The high content of calcium in coal is an important cause of serious ash deposition.This paper uses molecular dynamics to calculate the diffusion and binding characteristics of calcium-containing minerals in the pore size of the oxide film.The results show that as the pore size of the oxide film increases,the movement of calcium-containing minerals becomes more intense and the reaction activity increases.Calcium-containing minerals with large pore diameters are easier to fill into the pores of the oxide film.When the pore size is 4nm,CaO and CaSO4 are easier to fill into the pores.CaSO4 reacts more easily withα-Fe2O3.CaSO4 adheres to the wall first.