Novel Inorganic/Polymer Composite Membranes
Project No.: DE-FE0007632
Ohio State University is developing a cost-effective design and manufacturing process for new membrane modules that capture carbon dioxide (CO2) from flue gas. The membranes consist of a thin, selective inorganic layer, embedded in a polymer structure so that it can be made in a continuous manufacturing process. They will be incorporated in spiral-wound modules for bench-scale tests using coal-fired flue gas. Preliminary cost calculations show that a single-stage membrane process is economically unfavorable, primarily because of the low concentration of CO2 (~14 percent) in the flue gas stream. A two-stage process is more economical, but requires plant operation with a CO2-enriched recycle stream.
An important cost driver in current carbon capture membrane technologies is the energy requirement for maintaining the driving force for the membrane separation. The flue gas must be kept at atmospheric pressure and the concentrated CO2 stream kept under vacuum (1.5 to 2.1 pounds per square inch [psi]) conditions. Preliminary calculations show that the carbon capture energy requirement can be sufficiently reduced in a two-stage process. In the first stage, CO2 is removed from flue gas by evacuation; in the second stage, the remaining CO2 is removed using an air sweep such that the 90 percent capture target is met.
|Supported Hybrid Membrane Concept