Abstract
Forty-seven tests were made on a continuous-ash-discharge spreader-stoker-fired boiler to determine means of reducing dust emission. In addition to burning rate, variables investigated were the amount of overfire air, the use of air, steam, and steam-air jets, the location of steam jets, the degree of reinjection used, and coal size. These tests showed that the use of overfire-jet turbulence decreased smoke density, carbon loss, and dust emission from the furnace. It was found that steam jets located low in the rear wall gave the lowest dust emission. Reinjection of all collected cinder decreased carbon loss to one fourth of its value without reinjection, but doubled the dust-loading of the stack gases. The use of double-screened coal was found to reduce dust emission appreciably.
This project was organized by Bituminous Coal Research, Inc., which obtained the participation of the American Engineering Company, Combustion Engineering-Superheater, Inc., Detroit Stoker Company, Hoffman Combustion Engineering Company, Iron Fireman Manufacturing Company, Riley Stoker Corporation, and Westinghouse Electric Corporation. The project was also supported by the General Motors Corporation which furnished the test site, special test facilities, and the coals used.
