Apparatus and process for the operation of an environmentally satisfactory coal fired plant

Claim 1

The process for operating a coal-fixed power plant in environmentally sound fashion by reduction of the emission of NO x and SO 2 , said power plant being provided with a boiler structure having at least one firing chamber, said at least one chamber having cooled walls and a burner muffle and an accelerating nozzle, and means for firing said chamber with a coal dust fuel whereby said fuel is heated rapidly before being mixed with combustion air and is rapidly cooled by said walls before being discharged, the steps comprising: preparing a coal dust fuel having a surface-active ash, injecting said fuel into the return flow of a flame in said burner muffle, said firing chamber having a load of 5-15×10 6 kcal/m 3 hr, heating said coal dust at a rate of at least 1000° C./sec. to a temperature above the ignition point of the coal dust with combustion air at an intensity such that a firing-chamber load of 5-15×10 6 kcal/m 3 hr with respect to said burner muffle and said accelerating nozzle is obtained, producing a flame jet in the accelerating nozzle at a velocity of at least 100 m/sec., cooling the flame jet by intermixture with cooled flame gases from the firing chamber in less than 0.1 sec. to less than 1000° C. gas temperature, and discharging the cooled flame gases with at least part of the ash in the form of dust from the firing chamber.