常温高压液化分离CO2-N2二元气体的实验研究OA

Carbon emissions from coal mining and utilization are the main cause of greenhouse effect.In order to reduce CO2 emissions and achieve the goal of carbon neutrality,an integrated approach combining in-situ coal pyrolysis mining with CO2 capture,utilization,and storage(CCUS)technology has been proposed.To address the separation of CO ₂ from high-temperature and high-pressure products generated during in-situ coal pyrolysis,and to further optimize CCUS technology,it is necessary to conduct in-depth investigations into the properties of CO2.However,experimental studies on the properties of CO2 in multicomponent mixture systems under ambient-temperature and high-pressure conditions remain limited.To investigate the behavior of CO2 in multicomponent mixture systems under ambient-temperature and high-pressure conditions,CO2 liquefaction experiments and CO2 solubility experiments were conducted in the laboratory.The dissolution and liquefaction characteristics of CO2 in the CO2-N2 binary mixture system at 287.15 K were obtained under different pressures,with initial CO2 molar fraction of 30%,40%,50%,and 60%,respectively.The results show that,at 287.15 K and within the pressure range of 5 MPa to 9 MPa,before reaching the critical pressure of CO2,higher system pressure leads to enhanced CO2 liquefaction,and the higher the initial molar fraction of CO2 in the system,the better the liquefaction effect.For the gas mixture with an initial CO ₂ molar fraction of 60%at 7.25 MPa,the CO2 molar fraction can be reduced to 38.25%.When the pressure exceeds 7.38 MPa at 287.15 K,CO2 can transform from the liquid phase into the dense phase,and the solubility of CO2 will suddenly increase from 13.38%to 18.45%.