GB463037A - Improved method and apparatus for treating and incinerating sewage sludge or the like waste material - Google Patents

Abstract

463,037. Refuse-oonsuming furnaces. NICHOLS ENGINEERING & RESEARCH CORPORATION. Aug. 16, 1935, No. 23082. Convention date, April 26, 1935. [A Specification was laid open to inspection under Sect. 91 of the Acts, Feb. 18, 1936.] Addition to 432,198. [Classes 51 (i) and 51 (ii)] A modification of the method described in the parent Specification for treating sewage sludge &c. consists in subjecting the gases evolved from the material under treatment in a furnace to a temperature, 1200 to 1500‹ F., sufficient to eliminate noxious odours therefrom during their passage through an intermediate zone or zones of the furnace. The material is fed from a hopper 12 into a furnace of the superposed hearth type having a vertical rabble shaft with stirring arms 30, 31 through which cooling air is passed and afterwards led to a recuperator (not shown) traversed by waste gases for heating the air. The material is dried on the upper hearths and incinerated on lower hearths, the residues being discharged at 14. Air is supplied from the recuperator and pipes 24a, 24b to openings 26 in the side walls of the furnace and delivered over the hearths. As shown in Fig. 3, the openings 26 are provided with burners 48 to which the supply of air for combustion is controlled by dampers 45, 46. The sewage sludge before admission to the hopper 12 is filtered to form a filter cake the moisture content of which is between 60 and 85 per cent. The burners 48 are put into or out of operation according to the nature of the material being treated. British Specification 22022/10, [Class 51 (ii)], and U.S.A. Specification 1,669,925 are referred to.