| dc.description.abstract | With the industry development, the concentration of greenhouse gas increases year by year, and thus more and more solar radiation is restrained in the atmosphere, resulting in the increase of average global temperature gradually. The abnormal average global temperature will cause melting ice in polar region, climate change and the increased spreading speed of infectious diseases. Consequently, how to reduce the emission of greenhouse gas has become an important issue all over the world.
This research is the experimental study of concentrating high purity CO2 from syngas after oxy-fuel combustion by dual-bed pressure swing adsorption process. Syngas after oxy-fuel combustion and dehydration will produce CO2 with purity more than 95%, and therefore the composition of feed gas used in the process was assumed 95% CO2, with 5% N2 balanced. We chose UOP 13X zeolite as the best adsorbent that will be used in the dual-bed PSA process according to the adsorption capacity and selectivity of CO2 over N2 comparing to other zeolites.
The breakthrough and desorption curves were discussed by changing different feed flow rate and temperature. Next the carbon dioxide was purified by dual-bed six-step pressure swing adsorption process. After exploring the effects of variables such as temperature, feed pressure, vacuum pressure, purge to feed ration, and step time on performance of pressure swing adsorption process, we found the best operating conditions for obtaining high purity carbon dioxide among our experiments. The best operating conditions are feed pressure 3.45 atm, countercurrent depressurization pressure 0.48 atm, temperature 358 K, feed pressurization / countercurrent depressurization step time 150 s, adsorption / purge step time 20 s, cocurrent depressurization / idle step time 250 s, purge to feed ratio 0.105. The experimental results of best conditions are 99.94% purity and 42.84% recovery of carbon dioxide at bottom product, energy consumption 0.304 GJ/tonne CO2 and productivity 0.136 kg CO2/kg adsorbent．h。 | en_US |