The report gives results of a technical assessment of the advisability of increased use of stoker coal for residential and small commercial space heaters. The assessment was based on: (1) an experimental laboratory study (major emphasis) to evaluate emissions from a 20-hp (200 kw) boiler firing anthracite, Western subbituminous, processed lignite char (smokeless coal), and high and low volatile bituminous coals (pollutants of major interest were smoke, particulate, and POM); (2) a survey to identify manufacturers and designs of currently marketed stokers; and (3) a survey to identify processes for the manufacture of smokeless coals and to evaluate the suitability of these fuels for stoker firing. The experimental investigation indicated that smokeless operation of a small stoker could be achieved for the coals evaluated (coals generating the highest smoke levels generated the highest particulate and POM levels). Coals with the highest volatile matter and the highest free swelling index had the highest levels of these emissions. It also indicated that a potential exists to reduce emissions both by minor modifications in the stoker design and operation, and by use of processed or treated coals. Even these emission levels would be considerably higher than those from equivalent oil- and gas-fired systems.

"EPA 600-7-76-029." "October 1976." Cover title. Prepared by Battelle-Columbus Laboratories, Columbus, Ohio, under contract no. 68-02-1848, program element no. EHE624. Chiefly tables. Includes appendices. Includes bibliographical references (pages 76-77).