Abstract: A rotatable throat for a coal pulverizer is improved by creating a high pressure drop in the air ports which surround the throat. The lower portions of the air port nozzles are made of vanes and relatively thin sides, and shaped to provide air entrance areas from five to six times the release points of the nozzles.

Abstract: A kit of segments is provided for replacing the throat of a coal pulverizer. The segments are so constructed that they may be assembled as either a rotatable throat or a stationary throat, and easily converted in place from one mode to the other. In the rotatable mode, the ledge covers over the throat segments are rotated with the throat.

Abstract: A coal pulverizer, that supplies a coal-in-air mixture to combustion means for a power plant and comprises grinding means consisting of wheels revolving in a power driven trough from which pulverized coal is centrifugally thrust into a stream of forced air blown upward through air passages in a throat ring consisting of uniformly sized segments, is provided with a wear ring of uniformly sized segments resting flush on the throat ring segments of equal arcuate dimension. Each said wear ring has a substantially trapezoidal cross section, the base of which rests on a throat ring segment, the vertical face of which fits against the inner wall of the pulverizer and the sloping face of which rises upward from its base at an angle measured from the vertical of between ten and seventeen degrees for approximately 21/2 and 31/2 inches, so as to deflect the coal-air stream away from direct impingement on the pulverizer housing.

Abstract: In the vertically oriented generally cylindrical coal pulverizers that are widely employed to supply a coal-air dispersion to the combustion zones of boilers producing steam for the turbines of electric-power plants, forced-air requirements are reduced and coal fall-back and resultant coal fires are substantially eliminated by the novel throat ring of invention. A throat ring surrounds circumferentially the coal grinding assembly of each such pulverizer and contains a plurality of angularly disposed air channels through which air is forced upwardly into contact with pulverized coal thrust centrifugally from the said assembly causing the coal-air mixture to swirl upwardly to means directing the mixture to the said combustion zones.