碳酸二甲酯吸收捕集CO_2工艺流程

Continuous absorption-desorption system for CO_2 capture with dimethyl carbonate

采用在线气相色谱测定了碳酸二甲酯(DMC)-CO2体系的气液相平衡,并得到了25,35,45℃下的亨利系数分别为6.566,7.614,8.784 MPa。同时建立了一套连续吸收-解吸小试装置,考察了DMC用于捕集CO2的吸收-解吸连续运行情况。并结合Aspen Plus模拟软件,分析了DMC在连续吸收-解吸小试装置上运行的最佳操作参数,并得到整体工艺能耗。结果表明:实验研究范围内,最佳的操作参数为液气摩尔比1.556、吸收温度20.0℃、解吸温度为63.2℃,相应的吸收率为94.34%,捕集CO2能耗为1.72 GJ/t。

An on-line chromatography system was used to determine the vapour-liquid equilibrium of CO2 in dimethyl carbonate（ DMC）. The Henrys＇ coefficients at 25,35,45 ℃ were fitted as 6. 566,7. 614,8. 784 MPa,respectively.The measured values reasonably agreed with those results from literature. A continuous CO2 absorption-desorption system was established to evaluate performance of DMC. With the help of Aspen Plus simulation the operating parameters and capture consumption were analyzed and optimized. The CO2 removal efficiency was accelerated with the decrease of absorption temperature,the increase of absorption pressure and the same trend of desorption temperature. But the CO2 removal efficiency was decreased firstly and then increased as the increasing of liquid-vapor mole ratio（ L /V）. The CO2 capture consumption was minimized as the operation conditions changed. It shows that under the optimum conditions of L /V 1. 556,absorption temperature 20. 0 ℃ and desorption temperature 63. 2 ℃,the absorption yield of 94. 34% and unit CO2 trapping consumption of 1. 72 GJ /t can be achieved.