AECOM Process Technologies provided engineering and procurement services to upgrade the flue gas desulfurization (FGD) systems using soda ash as a reagent on Units 1, 2, and 3 at the Jim Bridger Plant near Rock Springs, Wyoming. The primary goals of the FGD upgrade were to increase SO₂ removal to meet new, stricter emission limits for the plant and to improve reliability by reducing significant quantities of solids accumulating on trays and mist eliminator surfaces. The upgrade included the following revisions: new hollow cone nozzles, new high-efficiency spray headers, new sieve trays, and new mist eliminator and wash systems. AECOM Process Technologies conducted a computational fluid dynamics (CFD) study to improve gas-liquid contact to reduce equipment plugging resulting from a wet-dry interface that extended throughout the absorbers.

AECOM Process Technologies also conducted a characterization study to identify other potential causes of solids accumulation. Based on the results of the characterization study, AECOM Process Technologies optimized the operation of a softener treating cooling tower blowdown for use as makeup to the scrubbers. AECOM Process Technologies successfully completed the upgrade of the first unit during the summer of 2009 and the second during 2010. The final unit was upgraded during an outage in 2011.