Advances of Syngas Chemical Looping Process at the Ohio State University: Pilot Demonstration and Advanced Control Architecture Development

For the past two decades, The Ohio State University (OSU) has been advancing chemical looping technologies as a promising alternatives to conventional processes for chemical and power production with greater process efficiency and carbon emissions reduction. The unique design of counter-current and co-current moving bed can efficiently convert various types of fuel to electricity and/or high value chemicals with nearly 100% CO₂ capture. The presented paper summarizes the most updated development and demonstration results of two syngas chemical looping (SCL) test facilities at OSU – the 250 kW_th-3 MW_th pilot plant and 25 kW_th sub-pilot unit. Specifically, the SCL pilot plant converts syngas produced by coal gasification and generates sequestration-ready CO­₂, while producing high purity H₂ with minimal particle circulation. Key design features and experimental data will be discussed. The sub-pilot unit is implemented with an advanced control architecture that enables autonomous start-up, steady state operation and shut-down. The developed hybrid controller, which consists of high level controllers (HLCs) and sliding mode controllers (SMCs), significantly reduces operator intervention requirements during the entire operation. The capabilities of the controller, including disturbance rejection, stage recognition and designed state transition will be presented.