CCS and Power Systems
Advanced Energy Systems - Gasification Systems
Chemical Looping Gasification for Hydrogen Enhanced Syngas Production in the Reaction Mixture Carbon Dioxide Capture
Performer: Ohio State University
Project No: FE0012136
Program Background and Project Benefits
In general, gasification is used to convert a solid feedstock, such as coal, petcoke, or biomass, into a gaseous form, referred to as synthesis gas or syngas, which is primarily hydrogen and carbon monoxide. With gasification-based technologies, pollutants can be captured and disposed of or converted to useful products. Gasification can generate clean power by adding steam to the syngas in a WGS reactor to convert the carbon monoxide to carbon dioxide (CO2) and to produce additional hydrogen. The hydrogen and CO2 are separated—the hydrogen is used to make power and the CO2 is sent to storage, converted to useful products or used for enhanced oil recovery. In addition to efficiently producing electric power, a wide range of transportation fuels and chemicals can be produced from the cleaned syngas, thereby providing the flexibility needed to capitalize on the changing economic market. As a result, gasification provides a flexible technology option for using domestically available resources while meeting future environmental emission standards. Polygeneration plants that produce multiple products are uniquely possible with gasification technologies. The Gasification Systems program is developing technologies in three key areas to reduce the cost and increase the efficiency of producing syngas: (1) Feed Systems, (2) Gasifier Optimization and Plant Supporting Systems, and (3) Syngas Processing Systems.
Syngas processing research and development underway emphasizes technologies that can be efficiently integrated into the plant, optimized with the temperature and pressure requirements of other systems, and meet product delivery specifications. A major cost element in gasification plants is converting raw syngas into a pure and specific gas used to create the plant's target product suite. High-hydrogen, low-methane, ultraclean syngas is versatile and can be used for power production with CO2 capture, fuels or chemicals production, and for many polygeneration applications. The technologies being developed are focused on high-efficiency processes that operate at moderate to high temperatures and clean syngas of all contaminants to the extremely low levels needed for chemical production—often significantly lower than the U.S. Environmental Protection Agency (EPA) required levels for power plants.
This Ohio State University project will further demonstrate the technical and economic advantages of a chemical looping gasification (CLG) process in context of integrated gasification combined cycle (IGCC) and coal-to-liquid plants. Project objectives are to 1) improve oxygen carrier performance, 2) demonstrate the CLG process at bench-scale to achieve greater than 98% coal conversion, 3) identify the effects and fates of sulfur, nitrogen, and other trace contaminants, 4) model cold-flow at sub-pilot scale, and 5) perform a comparative techno-economic analysis that validates the feasibility and attractiveness of the CLG system. Commercialized CLG technology is expected to improve the efficiency of coal-based gasification systems for both electricity generation and liquid fuels production while minimizing their carbon footprints.
MIT Technology Review A Cleaner Way to Use Coal provides more background on coal gasification chemical looping.