Chapter 7: Membranes

One can also use membranes to separate gasses. Normally membranes operate using a large pressure difference, but flue gas is at the “end of the pipe,” and thus the exhaust pressure is very close to atmospheric pressure. Compressing flue gas is very expensive, so membrane separation does not look very attractive for carbon capture. We show that one can nevertheless arrive at promising process options by immersing oneself into the physics and chemistry of the membrane, then using that knowledge in clever process design schemes.