Simultaneous SO2 and NOx separation preferably in fluidized-bed combustion plants

摘要

The invention relates to a process for the simultaneous SO2 and NOx separation from the flue gases of fossil-fuel fired combustion boilers, preferably fluidized-bed combustion plants. It has been found that, by the addition of lime and ammonia salt to the fuel mixture during combustion, SO2 is separated off via binding to lime and NOx is converted to elemental nitrogen as a result of reduction by ammonia. In order to prevent the lime being able to react with the ammonia salts (specifically in the case of wet coal) prior to use in a combustion chamber and NH3 being liberated, according to the invention, pitch, asphalt, slack waxes etc. are added to the fuel mixture and are pressed to form fuel pieces in the form of briquettes, egg coal etc., in order to insulate the added salts and enable them to react only in the combustion chamber.