Gas phase mass transfer in falling film microreactors (FFMRs) with the absorption of CO2 into aqueous solutions of NaOH was investigated.The overall gas-phase mass transfer coefficient increases with NaOH concentratio...Gas phase mass transfer in falling film microreactors (FFMRs) with the absorption of CO2 into aqueous solutions of NaOH was investigated.The overall gas-phase mass transfer coefficient increases with NaOH concentration,but decreases as the concentration of CO2 increases.There exists an entrance effect,hindering the mass transfer,which is caused by the dead volume for gas-phase flow in the gas chamber in FFMRs.The entrance effect has a larger impact in a shorter FFMR owing to the relatively large dead volume with respect to that of gas chamber.A decrease in the depth of gas chamber facilitates the mass transfer process.Therefore,the gas-phase entrance or geometry of the gas chamber should be designed appropriately to reduce the entrance effect and improve the mass transfer.展开更多
This paper studies the mass transfer performance of structured packings in the absorption of CO2 from air with aqueous Na OH solution. The Eight structured packings tested are sheet metal ones with corrugations of dif...This paper studies the mass transfer performance of structured packings in the absorption of CO2 from air with aqueous Na OH solution. The Eight structured packings tested are sheet metal ones with corrugations of different geometry parameters. Effective mass transfer area and overall gas phase mass transfer coefficient have been measured in an absorption column of 200 mm diameter under the conditions of gas F-factor in 0.38–1.52 Pa0.5and aqueous Na OH solution concentration of 0.10–0.15 kmol·m-3. The effects of gas/liquid phase flow rates and packing geometry parameters are also investigated. The results show that the effective mass transfer area changes not only with packing geometry parameters and liquid load, but also with gas F-factor. A new effective mass transfer area correlation on the gas F-factor and the liquid load was proposed, which is found to fit experiment data very well.展开更多
文摘Gas phase mass transfer in falling film microreactors (FFMRs) with the absorption of CO2 into aqueous solutions of NaOH was investigated.The overall gas-phase mass transfer coefficient increases with NaOH concentration,but decreases as the concentration of CO2 increases.There exists an entrance effect,hindering the mass transfer,which is caused by the dead volume for gas-phase flow in the gas chamber in FFMRs.The entrance effect has a larger impact in a shorter FFMR owing to the relatively large dead volume with respect to that of gas chamber.A decrease in the depth of gas chamber facilitates the mass transfer process.Therefore,the gas-phase entrance or geometry of the gas chamber should be designed appropriately to reduce the entrance effect and improve the mass transfer.
基金Supported by the National Natural Science Foundation of China(51134017)and Petro China(2011E-24-09)
文摘This paper studies the mass transfer performance of structured packings in the absorption of CO2 from air with aqueous Na OH solution. The Eight structured packings tested are sheet metal ones with corrugations of different geometry parameters. Effective mass transfer area and overall gas phase mass transfer coefficient have been measured in an absorption column of 200 mm diameter under the conditions of gas F-factor in 0.38–1.52 Pa0.5and aqueous Na OH solution concentration of 0.10–0.15 kmol·m-3. The effects of gas/liquid phase flow rates and packing geometry parameters are also investigated. The results show that the effective mass transfer area changes not only with packing geometry parameters and liquid load, but also with gas F-factor. A new effective mass transfer area correlation on the gas F-factor and the liquid load was proposed, which is found to fit experiment data very well.