Fired Heater Sulfur in Fuel Gas Regulations
The Federal New Source Performance Standard (NSPS) for gas fired refinery process heaters restricts sulfur compounds in the fuel. This standard also applies to modifications of existing fired heaters (stationary sources).
What is a modification? It is defined by EPA as “any physical change in, or change in the method of operation…which increases the amount of any air pollutant (to which a standard applies)…or which results in the emission of any air pollutant (to which a standard applies) not previously emitted.” However, routine maintenance, repair and replacement, increased production within the design capacity, and fuel switches already accommodated in the design, are excluded.
This standard (NSPS Subpart J, 40CFR60.100) imposes a 160 ppm limit on sulfur compounds in the fuel, with continuous monitoring required. Alternatively, the owner can usually elect to limit stack sulfur dioxide emissions, if the EPA Administrator is satisfied that this will provide equivalent control. Again, continuous monitoring is required.
More stringent New Source Performance Standards, which also usually apply to modifications of existing sources, may be imposed by local authorities. Obviously, this is an important point to check when contemplating a new installation or modification at a particular location.