状态方程在气固相平衡计算中的应用

Application of EOS in Calculation of Gas and Solid Phase Equilibrium

状态方程法是研究气固平衡的一种常用方法,但是目前仅有SRK和PR方程运用于元素硫沉积机理的研究。采用RK、SRK、PR、PT和LHSS状态方程对含硫天然气气固相平衡进行了计算,并且比较了不同状态方程对计算结果的影响。通过算例分析可知,对含硫天然气气固相平衡进行计算时每种状态方程都会存在误差,而误差主要来源于实验过程中的误差、状态方程参数设置的误差、数值计算方法的误差等。计算结果表明,采用RK和SRK方程计算误差较大,PR和PT方程两者计算误差差别不大,LHSS方程更适合描述含硫天然气的气固相平衡。

The method of state equation is commonly used to study gas-solid equilibrium, but only SRK and PR equations are applied to study the mechanism of elemental sulfur deposition currently. In this paper, gas-solid phase equilibrium of sour natural gas was respectively calculated by using RK,SRK,PR,PT and LHSS state equations, the influence of different state equations on the calculation results was also compared. The result shows that all state equations have error when calculating gas-solid phase equilibrium of sour natural gas, and the error is mainly from experimental process, setting of state equation parameters, numerical methods and so on. The calculation results show that the error is big when using RK and SRK equations to calculate, and there is little difference in the error between PR and PT equations. In addition, LHSS equation is more appropriate to describe gas-solid phase equilibrium of sour natural gas.