Chemical Looping Prospective: An Advanced Approach to Coal Utilization
Chemical looping technologies have evolved into a promising alternative for the efficient conversion of carbonaceous fuels to electricity and/or high-value chemicals with minimal carbon emissions. These processes utilize an oxygen carrier solid material to indirectly supply oxygen to the fuel source. With the exponential growth of research and publications in this field, chemical looping has expanded to encompass power and chemical production with in-situ gas separation. This presentation will summarize the chemical looping concept, its 220-year history, its advantages and the challenges faced by those researchers developing these processes. The present presentation will also summarize the key developments of 3 chemical looping processes – the 250kWth syngas chemical looping (SCL) pilot plant, the coal direct chemical looping (CDCL) 25 kWth sub-pilot unit and 250 kWth pilot plant, and the 15 kWth coal to syngas (CTS). Key process design features and experimental results from over 1,500 hours of cumulative operation will be discussed. The counter-current moving bed reactor design the CDCL and SCL process ensure nearly full fuel conversion to CO2 with minimal solid circulation and capability of producing high purity H2. These processes developed by The Ohio State University have the potential to transform the way coal is used today to produce power and high-value chemical products.