Desulphurization of Carbonaceous Fuel

摘要

First, nitrogen oxides are reduced by firing coal in substoichiometric air conditions in a first stage oxidation unit of a combustor to reduce NOx from fuel bound nitrogen. Hydrated lime, Ca(OH)2, is introduced into the first stage oxidation unit to produce calcium sulfide. The calcium sulfide becomes tied up in a slag eutectic which is removed prior to entry of the fuel gas to a second stage oxidation unit at the entrance of a furnace where additional preheated air is added to the fuel gas.