GB423930A - Improvements in methods of and furnaces for burning granular fuel and the like - Google Patents

Abstract

423,930. Pulverulent-fuel furnaces. STOUFF, L. M. J., 101, Boulevard des Belges, Lyons, France. July 7, 1933, Nos. 19350, 19351, 19352, and 19353. Convention dates, July 7, 1932, Nov. 10, 1932, Nov. 14, 1932, and Jan. 27, 1933. [Class 51 (i)] In a furnace in which granular fuel is fed in at the top f, Fig. 1, and descends against an upwardly directed air current, the ash being removed from the bottom d of the furnace, the combustion chamber b is in the form of a truncated cone having an angle of not more than about 25‹ and of such length that the cross sectional area of the upper end is not less than about 15 times the cross section at the lower end. The combustion chamber is formed with a lower extension through which air is supplied. In one form, Fig. 2, the lower part 1 is formed with side air inlets 14, 15 and 16 and with a lower opening through which projects an air pipe 4 the blast from which induces a further supply through the surrounding annular space 5. A tangentially arranged air supply pipe 13 may also be provided. A conical plug 12 on the pipe 4 may be adjusted vertically to vary the opening 5. Loosely mounted on the pipe 4 is a sleeve 6 rotated by gearing 10, 11 and operating through a rod 7 a yieldingly mounted scraper 8 for removing slag. The lower part 1 may be vertically displaced to form an adjustable annular air inlet 17. In a modified form, Fig. 4, the lower end of the furnace is formed by conveying belts such as 21, 22 which allow the passage of air and assist the discharge of slag. Screens 32 adjust the level at which air is delivered. In a further modification, Fig. 6, the lower part of the furnace is formed by bars 33 actuated by eccentrics 38 so that the lower ends move inwardly and downwardly and then outwardly and upwardly, the upper ends sliding on guiding rods 36. Alternate bars or groups of bars are 180‹ out of phase. In a further modification the lower part is formed by a perforated water jacket. The sides of the combustion chamber may be formed with recesses or pockets in which the air is relatively quiescent and in which ash collects to be removed later.