Fuel Tech, Inc. engages in the development, commercialization, and application of technologies for air pollution control, process optimization, water treatment. and advanced engineering services to utility and industrial customers. It operates through two segments, Air Pollution Control Technology and FUEL CHEM Technology. The Air Pollution Control Technology segment offers technologies to reduce nitrogen oxide (NOx) emissions in flue gas from boilers, incinerators, furnaces, and other stationary combustion sources; NOxOUT and HERT SNCR Selective Non-Catalytic Reduction systems; advanced selective catalytic reduction systems comprising Ammonia Injection Grid, and GSG Graduated Straightening Grid systems. I-NOx integrated NOx reduction systems; ESP processes and services; ULTRA technology; and flue gas conditioning systems. The FUEL CHEM Technology segment provides programs to improve the efficiency, reliability, fuel flexibility, boiler heat rate, and environmental status of combustion units for the control of slagging, fouling, corrosion, opacity, and acid plume, as well as the formation of sulfur trioxide, ammonium bisulfate, particulate matter, sulfur dioxide, and carbon dioxide through the addition of chemicals into the furnace using TIFI Targeted In-Furnace Injection technology. This segment offers its FUEL CHEM program for plants operating in the electric utility, industrial, pulp and paper, waste-to-energy, and university and district heating markets; and the owners of boilers, furnaces, and other combustion units for treating a wide variety of solid and liquid fuels, including coal, heavy oil, black liquor, biomass, and municipal waste. The company offers DGI Dissolved Gas Infusion systems, which utilizes a proprietary channel injector and a patented saturator that infuses oxygen, carbon dioxide, or other gases into water; and UDI Urea Direct Injection systems. It operates in the United States, rest of the Americas, Europe, South Africa, the Pacific region, and internationally. Fuel Tech, Inc. was incorporated in 1987 and is headquartered in Warrenville, Illinois.