陕西神华烟煤直接液化反应动力学模型

Kinetics of Direct Liquefaction of Shenhua Bituminous Coal

采用文献发表的神华烟煤间歇高压釜液化反应实验数据,将煤液化反应分为升温阶段和恒温阶段,建立了相应的动力学反应模型。通过使用BFGS变尺度优化算法,获得了模型的动力学参数。结果表明,在液化反应升温阶段即液化初期,油和气体主要是由煤直接反应得到的,而非由前沥青烯与沥青烯二次转化而来的。在恒温阶段初期,易反应组分C1主要转化成前沥青烯与沥青烯,在恒温阶段后期,油和气主要是由前沥青烯与沥青烯转化而来。两阶段模型计算值与实验值的平均相对误差分别为4.04%,3.37%,模型拟合良好。模型假设在恒温阶段开始时煤中难反应组分C2部分归为活性较高的易反应组分C1,这使得优化拟合效果大幅改善。

Based on the published experimental data of Shenhua coal liquefaction reaction in a batch autoclave fbr a heating-up and an isothermal stages, kinetic model was established. The model parameters were then obtained using BFGS optimization algorithm. The results show that, in the heating-up stage, oil and gas are mainly converted from coal rather than the further conversion of preasphaltene and asphaltene, in the beginning of the isothermal stage, oil and gas are primary converted from the easily reactive part C of the coal. In the later period of the isothermal stage, oil and gas are mainly obtained from the further conversion of preasphaltene and asphaltene. The model assumes that, at the beginning of the isothermal stage, some components of the hardly reactive part C2 turns into the easily reactive part C with a higher activity; this results in the overall data fitting much better. The average relative errors between the model predictions and the experimental data of the two stages are 4.04% and 3.28% respectively.