石脑油裂解过程的建模与仿真

基于Kumar的石脑油裂解过程的分子反应动力学模型，建立了某厂60kt／a裂解炉辐射段石脑油裂解数学模型。提出了通过ASTM值、PONA值等易测参数估算石脑油平均生成热、平均比热容和热导率等参数的方法，其估算值与分析值的相对误差低于1％；利用一种随机搜索算法对一次反应选择性系数进行了调整，主要裂解产物仿真收率与实测收率吻合良好；基于以芳烃为结焦母体的结焦反应动力学模型，建立了辐射段炉管运转周期的模型，在保持裂解气出口温度和出口压力不变的情况下，考察了炉膛温度、管外壁温度、焦层厚度等参数在整个裂解周期中的变化情况，仿真结果与实际情况比较吻合，可用来对裂解炉运转周期进行预测。

MODELING AND SIMULATION OF NAPHTHA PYROLYSIS PROCESS

Based on Kumar's molecular kinetic models of naphtha pyrolysis process, a mathematical model for the radiant section of a 60kt/a pyrolysis furnace was established. A method was brought forward to estimate the mean parameters of naphtha, such as average heat of formation, specific heat and heat conductivity, from the ASTM and PONA data of the naphtha. The relative errors of the estimated value and the analyzed value were all less than 1%. A stochastic method was introduced to modify the selectivity coefficients of the primary reaction. The simulation results of the main product yields were in conformity with the experimental data. Based on the coking model through the coke precursor, aromatics, in naphtha. A running period model was built for the radiant tubes. Assuming the outlet temperature and pressure kept constant in the whole period, the variations of the temperatures of the firebox and tube outside as well as the coke layer thickness were investigated. The simulation results were agreed with the experimental data. This work would be useful to predict the running period of the furnace.