| dc.description.abstract | Carbon capture and storage (CCS) is the process of capturing carbon dioxide (CO2) usually from large point sources, like coal-fired power plant, and depositing it where it will not enter the atmosphere. Among all the capture methods, IPCC thinks adsorption is the most potential capturing method and can be enlarged to the factory level.
Pressure swing adsorption process (PSA) is one of commercial technologies that are usually used to separate gas mixtures.According to the various selectivities of gas mixtures toward adsorbent, and based on the properties of adsorption at high pressure and desorption at low pressure, PSA uses these characteristics to achieve the target of gas separation.
This work presents a study for capturing carbon dioxide from dry flue gas (15% CO2 / 85% N2) emitted from coal-fired power plant using EIKME 13X as adsorbent.The breakthrough and desorption curves were discussed by changing different feed flow rate and temperature,and results were used to conduct the design of experiment of dual-bed PSA process. At this two-level fractional factorial design, parameter study was implemented to obtain a series of optimized settings of operating variables by investigating the effects of pressurization/cocurrent depressurization time, adsorption/countercurrent depressurization time, feed pressure, temperature, countercurrent depressurization pressure, and results show that the main effect of countercurrent depressurization pressure is significant for both CO2 purity and recovery.
As countercurrent depressurization pressure reaches the experimental lower limit of 0.05 atm, fixing temperature at 338K, feed pressure at 3.45 atm, pressurization/cocurrent depressurization time at 50s, then increasing adsorption/countercurrent depressurization time to 360 s, the process can get the CO2 purity of 83.71% and recovery of 76.10%.
Finally, by multiple regression analysis, we can get a regression model of CO2 purity and recovery, then via this model, we can make the decision of process improvement. | en_US |