GAS REBURNING-SORBENT INJECTION FOR CONTROLLING SOX AND NOX IN UTILITY BOILERS

As part of DOE's Clean Coal Technology program, a field evaluation of Gas Reburning‐Sorbent Injection (GR‐SI) technology is being carried out by Energy and Environmental Research Corporation. The project is cofunded by the Gas Research Institute and the State of Illinois Department of Energy and Natural Resources. GR‐SI technology is applicable to the control of emissions of acid rain precursor species, oxides of nitrogen and sulfur from coal fired utility boilers. Three units representative of pre‐NSPS design practices, a 117 MWe wall, a 71 MWe tangentially, and a 33 MWe cyclone fired boiler located in Illinois will be the host sites for this three‐phase demonstration project. Process specification studies have confirmed that GR‐SI technology is capable of achieving the stated goals of the project, 60 percent reduction in NOx and 50 percent reduction in SO2 emissions. NOx emissions will be reduced by staged fuel addition using natural gas as the reburn fuel, while SO2 emissions will be reduced by capturing sulfur by dry, calcium based sorbent injection which will be augmented by the displacement of about 15–20 percent of the coal input by natural gas firing. Phase 1, Design and Permitting, was completed earlier this year. In addition to process specifications which focused on injection system design criteria and precipitator enhancement approaches, detailed environmental information has been developed, including the assessment of waste disposal options and performing permitting work. In phase 2 of the project, anticipated to be initiated in 1989, installation and check‐out will be performed. The project will culminate in sustained 12‐month demonstrations of the technology on each host unit. Results of Phase 1 and plans for subsequent work will be discussed. Copyright © 1990 American Institute of Chemical Engineers