| Abstract: | Progress in dust collection by electrostatic precipitators with due attention to adsorption of noxious gases . It is shown on the basis of the present state of the art that the stipulations of the pollution control legislation for large boilers can be met by electrostatic precipitators and that fine dust and heavy metals are collected to a sufficiently high degree. Recent developments are dealt with which bring about a fundamental improvement of the collection in the precipitator. Noxious gases have to be separated together with the dust to an ever-increasing extent. With dry processes, fluidized beds are arranged upstream of the electrostatic precipitator for the adsorption of, for instance, HCl, HF, and SO2. In these cases the dusts will be highly concentrated and of varying chemical composition. Dry gas cleaning in the expanded, circulating fluidized bed downstream of refuse incineration plants and defluorination of waste gases from aluminium electrolysis are considered as examples. The separation of dust under difficult conditions is then dealt with. |
