Simulation And Analysis Of Rectisol Process

The Rectisol process using low-temperature methanol as an absorbent, removing acid gases selectively in the raw material gas, is a highly efficient gas purification and separation technology.The mathematical model of the key equipments in Rectisol process were established, the SRKM equation of state and Wilson equation were chosen to describe the vapor-liquid equilibrium of the system, and the key equipments and the whole Rectisol process were simulated by PRO/II simulation software. The simulation results of the key streams’ composition, temperature and flowrate, showed good agreement with the actual value. In the key equipments, the distribution of temperature and the composition was reasonable.This paper studied the operation of the key equipments under different conditions, and examined the impact of factors such as pressure, flowrate. Using Casestudy module in PRO/II software, the flowrate of fine-washing methanol in absorber, the pressure of flashing in MP-flash column and the stripping flowrate of nitrogen in reabsorber were analyzed. When the flowrate of the raw material gas is kept constant (13429kmol/h), the best flowrate of fine-washing methanol should be maintained at11000kmol/h; In the MP-flash column, when the operating pressure is stabilized at1.4MPa, the flowrate of CO2meets the requirements (250kmol/h); The best N2flowrate should be controlled at about500kmol/h.