GB568511A - Improvements in and relating to the removal of slag from furnaces - Google Patents

Abstract

568,511. Removing slag from furnaces. AKT.-GES. BROWN, BOVERI, & CIE. March 27, 1943, No. 5001. Convention date, April 16, 1942. [Class 51 (i)] In furnaces burning pulverulent slag-forming fuel, particularly of the pressure-fired type, wherein all or the main portion of the slag is carried in suspension from the combustion chamber by the hot gases and passed through a heat exchanger forming a main part of the heating surfaces receiving heat from the gases and cooled in the heat exchanger to approximately the temperature of solidification, the gases flow parallel to the heating surfaces and at a velocity of at least 100 metres per second. As shown in Fig. 1, pulverized fuel is fed by a burner 1 into a combustion chamber 4 lined with water tubes 5. Combustion products carry slag at high velocity through the tubes of the heat exchanger 10 in which the slag is cooled and deposited in the chamber 11 from which it is removed by a screw conveyer 17. Any slag which runs down the walls of the combustion chamber passes through an opening 19 into a receiver 20. The gases leave the chamber 11 and pass through an evaporator 14 to a superheater 15. The gases pass from the superheater to an exhaust gas turbine driving a blower for supplying air for combustion. Fig. 2 shows a scraper rod 25 for removing deposits from the top of the heat exchanger 10. The rod may be hollow for the passage of steam, air or water supplied by a pipe 29 to effect removal of the slag.