Process simulation of CO 2 capture from CO 2 ‐EOR associated petroleum gas with aqueous MEA and MDEA solvents

摘要

Associated petroleum gas produced by CO 2 ‐enhanced oil recovery (CO 2 ‐EOR) has a complex composition, high CO 2 content, and is unstable. To date, no integrated process simulation for CO 2 capture of the EOR associated petroleum gas has been developed. Based on the analysis of the associated petroleum gas obtained from the Shengli oilfield, a new full‐simulation model of CO 2 capture from 100?000?Nm 3 /d of the associated petroleum gas was developed for the process design of chemical absorption of blended amine solvents and an analysis of the relationship between different process parameters and the targeted result—low circulation flow and energy consumption—was performed using Aspen Plus (Version 8.6). A 90% CO 2 removal rate was achieved using 0.2?mol CO 2 /mol of a blended amine as solvent, with an energy consumption of 3.16 GJ/tCO 2 . By analyzing the influence of absorption pressure, temperature, and packing height on the circulation flow, the influence of absorption and desorption pressure on the energy consumption of the system was determined. It can be concluded that the optimal parameters are as follows: packing height of absorption column, 10?m; absorption temperature, 308.15?K; desorption pressure, 0.12 MPa; and CO 2 loading, 0.2?mol/mol of lean solvent, with an absorption pressure of 0.3‐0.6 MPa.