A Discussion on recent research in air pollution - Recent advances in electrostatic precipitators for dust removal

Abstract

The first essential in the prevention of atmospheric pollution is to remove the pollutant, or at least as much of it as is feasible, at source. Electrostatic percipitation is a well established process for removing dust from gases and careful attention to the many physical processes which are involved has allowed the development of the very large and highly efficient installations now required by the cement, electricity supply and the iron and steel industries. For example, a typical 2000 MW power station burning pulverized coal produces about 9.3 x 106m3 ( 330 x 106ft3) of flue gas per hour, containing about 100 tons of fly ash. The precipitators are specified to have a dust removal efficiency of 99.3 % at full load. They have a collecting electrode area of the order of 0.157 km2 (1.7 x 106ft2, or 40 acres); their cost, together with that of the associated dust handling plant, is about £ 3M, i.e. about 3 % of the complete boiler. The total amount of fly ash removed annually on all the C.E.G.B.’s pulverized fuel stations is between seven and eight million tons.