【摘要】 在工业生产中实现CO₂减排是一项艰巨的挑战，也是应对全球变暖的重要技术路线。CO₂捕集技术已得到了一定程度的发展，其中低温液化法具有可行性和经济性。利用工艺流程模拟软件Aspen Plus对低温液化分离CO₂工艺进行全流程模拟，选择3种物性方法对混合气的泡露点线进行模拟分析，基于某公司排放的含有高浓度CO₂的CO₂/N₂混合气为碳源，并对比文献数据，选择PR（Peng Robinson）状态方程作为本工艺的物性方法。分析了液化压力和温度对混合气液化率及CO₂纯度的影响，以CO₂液化率不低于90%、纯度不低于99.5%为目标，确定了最佳液化条件。为了最大限度地减少能耗，优化了冷却介质流量、冷凝温差、蒸发温度等工段参数，在最优条件下，CO₂液化率达91.80%、纯度达99.50%，液化单位总能耗最低为12.22 kW·h/kmol。该研究可为低温液化分离CO₂工艺设计与性能优化提供理论支持和技术参考。更多还原

【Abstract】 Realizing CO₂ emission reduction in industrial production is an arduous challenge and an important technological approach to combating global warming.CO₂ capture technology has been developed to a certain extent and the low-temperature liquefaction method is feasible and economical.The paper selects three physical property methods to simulate and analyze the bubble dew point line of the mixture with the process simulation software Aspen Plus,which can simulate the whole process of CO₂ separation by low-temperature liquefaction and chooses Peng Robinson equation as the method for this process using the CO₂/N₂ mixture with high concentration CO₂ as well as comparing with the literature data.It analyzes the effects of liquefaction pressure and temperature on the liquefaction rate of mixture and the purity of CO₂,determines the optimal liquefaction conditions at the condition of the liquefaction rate of CO₂≥90%and purity≥99.5%,optimizes such parameters as cooling medium flow rate,condensation temperature difference,and evaporation temperature to reduce the energy consumption to the maximum extent.The simulation results showed that the liquefaction rate of CO₂ can reach 91.80%,the purity of CO₂ can reach 99.50%,and the lowest total energy consumption per unit of liquefaction can be 12.22 kW·h/kmol under these optimal conditions,which could provide the theoretical support and technical reference in the technological design and performance optimization of CO₂ separation by lowtemperature liquefaction.更多还原