The report gives results of field measurements to determine particulate emission rate and particle size distribution for seven institutional-type stoker-fired boilers firing bituminous coals. Operational data were recorded during the tests to provide information for evaluating boiler emissions as a function of boiler load, heat release rates, coal size and characteristics, percent excess combustion air, and flue gas temperature. All boilers were tested under normal operating conditions at loads of 50-75% of maximum boiler capacity. The types of stokers tested included single retort underfeed, multiple retort underfeed, traveling grate overfeed, and vibrating grate overfeed. The report describes the seven boiler-stoker units, test port locations, and test equipment and procedures, and summarizes test results and operations. The particulate mass emission rate from high stack velocity sites was greater than from lower stack velocity sites, whether or not a collector was used: the statistical correlation coefficient was 0.83 with collectors and 0.98 without. The units tested can operate at 50-75% load with uncontrolled particulate emission rates, well below the calculated value of five times the weight percentage of ash in coal recommended in 'Compilation of Air Pollution Factors,' AP-42. Data indicate that 50% of the mass at the boiler outlet consists of less than 30 micrometer diameter particles.

"Pennsylvania State University." "February 1981." "IAG/contract nos. IAG-D7-E681FZ (EPA), EF-77-C-01-2609 (DoE), program element no. EHE624."