GB371398A - Improvements in apparatus for passing electric currents through gases - Google Patents

Abstract

<PICT:0371398/III/1> <PICT:0371398/III/2> In apparatus for passing electric currents through gases, particularly for the removal of suspended particles, having at least two electric fields, one of which extends in the direction of the gas stream and produces ionization of the gases, and the other of which extends across the gas stream and causes migration of the ions across the stream and charges the suspended particles in the gas which are then precipitated by the charging field or by a separate field at the precipitating electrodes, the ionizing are electrodes are arranged to form a substantially plane surface. The ionizing electrodes may consist of a series of parallel rods 20, 21 as shown in Fig. 1 connected alternately to a source of voltage 13, preferably alternating. The charging field is set up between electrodes 16, 17, which also serve as precipitating electrodes, fed by either alternating or direct voltage 18. The ionizing voltage is preferably high in comparison with the non-ionizing voltage. As shown in Fig. 4, the electrodes 46, 47 may be connected in parallel to one pole of the charging voltage, supplied by a transformer 60 and rectifier 62, the other pole being connected to one group 57 of the ionizing electrodes, thus giving two symmetrical charging fields, each between one set of ionizing electrodes and one electrode 46 or 47. The ionizing electrodes are supplied by a transformer 61. A condenser 67 is provided for smoothing the charging voltage. The ionizing electrodes or some of them may be covered with insulating material such as glass, porcelain, rubber, mica, gums, &c., or with semiconductive material such as slate, concrete or paper compositions containing metals, for example one set of ionizing electrodes 56 may be so covered and the other set left bare. Specification 319,217, [Class 1 (i), Chemical processes &c.], is referred to.