1.4-4 EMISSION FACTORS 7/98 in the use of combustion staging. However, gas reburning injects additional amounts of natural gas in the upper furnace, just before the overfire air ports, to provide increased reduction of NO x to NO 2. Two postcombustion technologies that may be applied to natural gas-fired boilers to reduce NO x emissions are selective noncatalytic reduction (SNCR) and selective
A steam boiler is a steam producing heating system; it produces energy by heating water to create steam. A steam boiler burns fuel to heat water. The combination of heat and water produces steam. Steam boilers are defined by their construction, portability, types of tubes, types of fuel, and the pressure they produce.