The report gives results of a study to ascertain the severity of blast-furnace slips and their accompanying bleeder-valve emissions as a source of air pollution. It describes factors contributing to the occurrence of hangs and slips in the blast furnace. It discusses the mechanics by which emissions occur from the bleeder valves. It presents data characterizing blast-furnace bleeder-valve emissions, including the frequency and duration of slip-induced bleeder-valve openings and the quantities of gas and dust issuing from open bleeder valves. It concludes that: (1) slip-induced bleeder-valve emissions are not an industry- or nation-wide problem; (2) these emissions may constitute an individual furnace and/or local air pollution problem; (3) less total particulates are emitted from this source than from other in-plant air pollution sources; and (4) the frequency of bleeder-valve emissions and, in turn, the severity of the problem have diminished over the last 20 years. The report discusses measures which may reduce the occurrence and/or severity of blast-furnace bleeder-valve emissions.

Contract no. 68-02-1323, task 60, program element no. 1AB604. Issued Oct. 1976. Includes bibliographical references (pages 33-35).