Pilot Test Results from a PolarisTM Membrane 1 MWe CO2 Capture System

Kniep, J., MTR
Baker, R., MTR
Chan, K., Membrane Technology and Research, Inc.
Huang, I., Membrane Technology and Research
Merkel, T., Membrane Technology and Research, Inc.
Nguyen, V., Membrane Technology and Research, Inc.
Sun, Z., MTR
Wang, X., MTR
To mitigate the harmful effects of global climate change, CO2 in combustion sources must be captured and either sequestered or utilized. Membrane technology is an attractive CO2 capture option because of advantages such as energy-efficient passive operation, small footprint, no hazardous chemical emissions, handling or storage issues, and reduced water requirements.

Working with the U.S. Department of Energy, MTR has developed new membranes and process designs to recover CO2 from combustion gases. PolarisTM membranes offer the highest combination of CO2 permeance and CO2/N2 selectivity of any commercial membrane today. These membranes are combined with a novel process design that uses incoming combustion air to sweep membranes and recycle CO2 to the combustion process. Design calculations estimate that this membrane process can capture CO2 at a cost $40-$50/tonne, which is competitive with leading second generation capture approaches.

Over the past 5 years, MTR has operated a system at the National Carbon Capture Center (NCCC) testing commercial-scale Polaris modules capturing 1 tonne CO2/day. Overall, this system has accumulated run time of over 11,000 hours, and demonstrated stable membrane performance. With this experience, MTR designed and built a scaled-up pilot unit to capture 20 tonnes CO2/day from a slipstream at NCCC (equivalent to 1 MWe-scale coal-fired power generation). This system was operated for about 1500 hours in 2015. During testing, advanced Polaris modules demonstrating higher packing density, lower pressure drop, and higher permeance were validated. After completion of testing at NCCC, the 20 tonne CO2/day unit was moved to Babcock & Wilcox’s (B&W) boiler research facilities for a fully integrated recycle test of the membrane unit with a coal-fired boiler. This test demonstrated boiler operation with CO2-laden air recycled by a membrane for the first time. Technical results from these field tests and future plans will be discussed in this presentation.