GB364491A - Process and apparatus for electrically separating suspended particles from gases - Google Patents

Abstract

<PICT:0364491/III/1> <PICT:0364491/III/2> <PICT:0364491/III/3> <PICT:0364491/III/4> <PICT:0364491/III/5> Apparatus for use in the electrical separation of suspended particles from gases comprises perforate collecting electrodes of hollow shape having discharge electrodes arranged centrally therein, and in which the gases entering the space enclosed by the collecting electrode are forced to escape through the perforations in a direction mainly radial, i.e. in the direction of the lines of force of the electrical field. The gas velocity is maintained approximately equal to the velocity of the particles due to the field, and efficient working can be obtained with a gas velocity of the order of 5 cms. per second. According to the embodiment shown in Fig. 1, the gas enters a hollow discharge electrode 2, preferably having a serrated edge 11 which prevents, by discharge to the earthed inlet pipe 12, dust passing into the space 13 surrounding the insulator 9. The gas passes through outlets 3, and then through the collecting electrode 4, which has its inner vertical surface equidistant at all points from the opposing surface of the discharge electrode. The precipitated dust falls into a hopper 6. One or more additional perforated collecting electrodes may be placed coaxially over the first one, or a series of discharge electrodes may be placed outside the collecting electrode to deposit any dust which may have passed through the perforations. These outer discharge electrodes may have a potential lower than the central discharge electrode. Centrifugal force and, or settlement by impact can be employed by giving the perforations in the collecting electrode the shape of curved nozzles as shown in Fig. 11, or by arranging the nozzles radially and opposed to a surface. The materials to be used for the electrodes may be, for example, metal screens, porous metals or semiconductors according to the materials treated. Fibrous material can be used, and may be coated with metal. The electrodes may also be flexible. Further examples of construction are shown in Figs. 3, 4 and 10.