Carbon capture driving force

Figure 2.8 Example of carbon dioxide separation from power plant flue gas using a two-step membrane process with two options for managing the permeate from the second membrane step. In Option 1 purple double-dotted lines), air is used directly in the burner while a vacuum pump creates partial pressure driving force in the second membrane step with return of the second step permeate to front of membrane process. In Option 2 blue dashed lines), the combustion air is used as a countercurrent permeate sweep gas in the second membrane step. Adapted from Figs. 11 and 12 in Merkel TC, Lin H, Wei X, Baker R. Power plant post-combustion carbon dioxide capture an opportunity for membranes. J Membr Sci 2010 359(1—2) 126—139.

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