柴油液相加氢过程中化学氢耗的研究

Study on the Chemical Hydrogen Consumption of Diesel Liquid-Phase Hydrogenation

在上流式固定床加氢中试实验装置上对柴油液相加氢过程中的化学氢耗进行研究,根据不同反应物的加氢反应方程推导出不同加氢反应的氢耗计算式,并建立了氢耗动力学模型。研究发现,在上流式柴油液相加氢过程中,前段催化剂床层的化学氢耗远远大于后段催化剂床层,70%的化学氢耗集中在前20%的催化剂床层上,从而导致后段床层H2浓度过低而影响加氢反应的进行;在进料量200 mL/h、氢/油质量比4.244×10-3、反应温度350℃和反应压力8 MPa条件下,化学氢耗计算值与实测值的平均相对误差为2.11%,表明推导的氢耗计算式准确、可靠;建立的氢耗动力学模型在预测化学氢耗时的相对误差小于2.0%,表明所建模型合理。

The chemical hydrogen consumption of diesel liquid-phase hydrogenation was studied in an up-flow fixed-bed hydrogenation pilot plant. The calculating equations of chemical hydrogen consumption were deduced based on various chemical reactions, and the kinetic model of hydrogen consumption was built. We reached the conclusion that chemical hydrogen consumption in the front catalyst bed is much higher than that in the back catalyst bed, because there is 70% of hydrogen consumption in the top 20% of catalyst bed, resulting in the bad reaction performance in the back catalyst bed due to the lack of sufficient hydrogen. Under the hydrogenation conditions of the feed rate of 200 mL/h, hydrogen to oil mass ratio of 4. 244 × 10^-3 , reaction temperature of 350℃ and reaction pressure of 8 MPa, the average relative error of calculated chemical hydrogen consumption is 2. 11%, as compared to actual value. The calculating equations we deduced were accurate and reliable. The relative error of chemical hydrogen consumption predicted by the hydrogen consumption kinetic model is less than 2. 0%, indicating that the model established in this paper is reasonable.