EES - Environmental Energy Services products

STEP Combustion’s over-fire-air (OFA) system designs provide NOx reductions of up to 35 % in typical applications.    Typical over-fire-air designs use 20-30% of the combustion air downstream of the primary combustion zone to deeply stage combustion beyond staging achievable with low NOx burners alone. STEP Combustion has extensive experience designing and optimizing OFA technologies applied to a wide range of boilers burning oil, gas, coal, and biofuels. STEP Combustion’s OFA port designs ensure good air/fuel mixing and carbon burnout throughout the boiler load range.

EES through our STEP Combustion group supplies Selective Non-Catalytic Reduction (SNCR) systems that reduce NOx by up to 40% on conventional boilers and up to 80% or more on fluidized bed boilers (C/BFB). STEP’s propriety high efficiency SNCR system utilizes urea or ammonia reagent which is injected into the post combustion flue gas stream to react with the NOx and form N₂ and H₂O. STEP’s Selective Non-Catalytic Reduction systems can use anhydrous ammonia, aqueous ammonia, or aqueous urea. SNCR NOx reduction systems can be applied to coal, biomass, fuel oil and gas fired units.

STEP Combustion also designs, engineers, and provides Selective Catalytic Reduction (SCR) systems which provide the highest level of NOx reduction.  As its name implies, the SCR uses a catalyst and injected reagent such as ammonia or urea to convert NOx to elemental nitrogen (N2. The reagent is injected upstream of catalyst housing and mixes with the flue gas. The SCR system NOx reduction can be engineered based on the catalyst dimensions, catalyst materials, cell density, reagent injection, temperatures, etc.