The Powder River Basin is a region in southeast Montana and northeast Wyoming, about 120 miles (190 km) east to west and 200 miles (320 km) north to south, known for its coal deposits. The region supplies about 40 percent of coal in the United States. Powder River Basin Coal is classified as "sub-bituminous" and contains an average of approximately 8,500 btu/lb, with low SO2. PRB coal contrasts with eastern, Appalachian bituminous coal which contains an average of 12,500 btu/lb and high SO2. The use of PRB coal has increased dramatically as a means to reduce air pollution emissions from power plants. However, its characteristics greatly increase the risk of fire and explosions.
DSI pioneered the use of Dry Fog to control hazardous PRB Coal Dust against material handling at PRB Mines and PRB Coal Fired Power Plants. Today, in Wyoming, Fogging Systems are considered Best Available Control Technology (BACT) for PRB Coal conveyor transfer points and given a ZERO VISIBLE EMISSIONS rating. The EPA classifies fogging systems as Best Demonstrated Technology (BDT) for sub-bituminous coal handling. Nearly every PRB Coal Mine now has a fogging system to control dust.
DSI is a leading supplier of dust control systems for plants using or converting to PRB Coal. DSI has installations throughout North America, including the most recent PRB Coal Fired Plants built in Gillette, Wyoming (Wygen 2, Wygen 3 and Basin Electrics Dry Fork Station).