CCS and Power Systems
Carbon Capture - Post-Combustion Capture
High Performance Thin Film Composite Hollow Fiber Membranes for Post-Combustion Carbon Dioxide Capture
Performer: General Electric Company
Project No: FE0007514
Program Background and Project Benefits
The mission of the U.S. Department of Energy/National Energy Technology Laboratory (DOE/NETL) Existing Plants, Emissions, & Capture (EPEC) Research & Development (R&D) Program is to develop innovative environmental control technologies to enable full use of the nation’s vast coal reserves, while at the same time allowing the current fleet of coal-fired power plants to comply with existing and emerging environmental regulations. The EPEC R&D Program portfolio of carbon dioxide (CO2) emissions control technologies and CO2 compression is focused on advancing technological options for the existing fleet of coal-fired power plants in the event of carbon constraints. Pulverized coal (PC) plants burn coal in air to produce steam, and comprise 99 percent of all coal-fired power plants in the United States. Carbon dioxide is present in the flue gas exhaust at atmospheric pressure and a concentration of 10–15 volume percent. Postcombustion separation and capture of CO2 is a challenging application due to the low pressure and dilute concentration of CO2 in the waste stream, trace impurities in the flue gas that affect removal processes, and the parasitic energy cost associated with the capture and compression of CO2. Polymeric membrane-based CO2 capture technologies are a potentially promising alternative to existing liquid sorbent-based options. Membranebased CO2 capture technologies have the potential to impact both the cost of electricity (COE) by reducing parasitic loads and operating costs, and the additional water demand, by eliminating the need to continuously cool the solvent stream.
Membranes based on coupling this novel phosphazene-based polymer with an engineered hollow fiber support could offer a higher efficiency CO2 capture process able to be retrofit to existing coal-fired power plants. The several specific process and material optimizations to be performed in this project have the potential to significantly improve the economics of CO2 capture, and to achieve the DOE performance criteria of capturing greater than 90 percent of the CO2 in coal-fired flue gas with less than a 35 percent increase in the COE.
Primary Project Goal
The overall goal of this project is to develop high performance, thin film polymer composite hollow fiber membranes and advanced processes for economical post-combustion CO2 capture from pulverized coal flue gas at temperatures typically found in existing flue gas cleanup processes.
The project goal will be attained by achieving the following objectives: (1) fabricating an engineered, highly porous, hollow fiber support for the novel phosphazene polymer, (2) optimizing robust coating processes to coat defect-free thin films of high performance phosphazene polymer on the hollow fiber supports, (3) fabricating a composite hollow fiber membrane that meets permeability and selectivity targets set by system modeling requirements, and (4) achieving the projected COE impact and CO2 recovery that meets or exceeds DOE goals.
Conduct preliminary technical and economic feasibility studies to refine performance targets.
Characterize and optimize phosphazene polymer separation performance on actual flue gas.
Modify the phosphazene material into easily-processed coating solutions.
Produce highly porous hollow fiber supports with controlled surface porosity. Optimize both the continuous dip and batch coating processes to provide economical and scalable coated composite hollow fiber membranes. Conduct preliminary membrane fouling and aging studies.
Test membranes at bench-scale in coal flue gas.
Conduct technical and economic feasibility analyses and an environmental, health, and safety assessment.