Simulation Of Rectisol Process Based On Non-equilibrium Model

For the simulation of multistage-separation process, equilibrium model has always been used. Because the actual chemical process is not so ideal, the use of equilibrium model is limited.In the present work, based on non-equilibrium model, the absorber, CO2desorber, H2S concentration column, regeneration column and methanol-water seperation column in a rectisol process have been simulated with PSRK property method by Aspen Plus software, and the simulation results are compared with the equilibrium model.The Rectisol process includes absorption process with low temperature, high pressure, and desorption process with high temperature, low pressure. The temperature and pressure between each tower of the entire process are very different. So in order to make the simulation results based on non-equilibrium model closer to the design values, PSRK property method is modified.Calculation results of the absorber, CO2desorber, H2S concentration column and regeneration column are analyzed, and the temperature, flow and mole fraction of key components are compared to design values. The calculation results of Methanol-water separation column are simply compared. Comparison of simulation results between the equilibrium model and non equilibrium model and comparison of simulation results of the absorbor based on Non-equilibrium model between this pater study and Yang Ting’s previous work are made.The simulation results of above five towers are consistent with the design values well based on non-equilibrium model, and they are better than the equilibrium model. This demonstrates that non-equilibrium model can be used for the simulation of the whole Rectisol process, which provides a reliable technology support for Rectisol process design.