Pressure swing adsorption (PSA) processes have been used extensively for gas separation, especially in the separation of hydrogen from CO2, and in air purification. The objective of this paper is to examine the economic feasibility of pressure swing adsorption (PSA) for recovering CO2 from postcombustion power plant flue gas. The analysis considers both high-pressure feed and vacuum desorption using commercial adsorbent 13X, which has a working capacity of 2.2 mol/kg and CO2/N2 selectivity of 54. The results show that using vacuum desorption reduces the capture cost from US$57 to US$51 per ton of CO2 avoided and is comparable in cost to CO2 capture using conventional MEA absorption of US$49 per ton of CO2 avoided. In this paper, a sensitivity analysis is also presented showing the effect on the capture cost with changes in process cycle; feed pressure and evacuation pressure; improvements the adsorbent characteristics; and selectivity and working capacity. The results show that a hypothetical adsorbent with a working capacity of 4.3 mol/kg and a CO2/N2 selectivity of 150 can reduce the capture cost to US$30 per ton of CO2 avoided.

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a b s t r a c tIn 2005, the IPCC SRCCS recognized the large potential for developing and scaling up a wide range of emerging CO 2 capture technologies that promised to deliver lower energy penalties and cost. These included new energy conversion technologies such as chemical looping and novel capture systems based on the use of solid sorbents or membrane-based separation systems. In the last 10 years, a substantial body of scientific and technical literature on these topics has been produced from a large number of R&D projects worldwide, trying to demonstrate these concepts at increasing pilot scales, test and model the performance of key components at bench scale, investigate and develop improved functional materials, optimize the full process schemes with a view to a wide range of industrial applications, and to carry out more rigorous cost studies etc. This paper presents a general and critical review of the state of the art of these emerging CO 2 capture technologies paying special attention to specific process routes that have undergone a substantial increase in technical readiness level toward the large scales required by any CO 2 capture system.