| Abstract: | Separation and measurement of very fine liquid and solid particles in the chemical industry. In comparison to power stations, the total amounts of waste gases emitted by the chemical industry are fairly low. On the other hand, the complexity of the waste gases and their components is far higher. In the chemical industry we can therefore not be content with one overal concept for gas purification, but must use a multitude of individual solutions. These should be applied at source, i.e. to each separate production plant. To solve an aerosol separation problem successfully and economically, a knowledge of the composition, the fineness and the amount of aerosols is essential. Cascade impactors have proved to be the most suitable instruments for a fractionated measurement of solid and liquid particulates in the super and sub-micron size range. The results of these measurements make is possible to choose the right equipment and to calculate its performance. Very complex aerosols, e.g. aerosols which are composed both of liquid and solid particles, or of sticky particles, are likely to present the most difficult problems. This article deals with a small selection of cases by demonstrating the problems of separation and the different ways of solving them. It considers among others acid mists and oil mists as well as organic mists, together with very fine particulates from waste incineration plants. |
