GB408489A - Improvements in or relating to the electrical precipitation of suspended particles from gaseous fluids - Google Patents

Abstract

<PICT:0408489/III/1> <PICT:0408489/III/2> In apparatus for the electrical separation of suspended particles from gases in which a spark-gap is interposed in the supply line to the discharge electrodes and an earthed condenser is connected in a branch line preceding the spark-gap, whereby voltage impulses with a steep wave-front are impressed upon the electrodes at each breakdown of the spark-gap, the condenser is arranged within the treater and the gases to be treated form its dielectric. This condenser also acts as a non-ionizing separation zone, wherein particles which have been ionized but not deposited in the ionizing portions of the treater are collected. In the arrangement shown in Fig. 1, the treater contains two units 33<a>, 33<b>, comprising discharge electrodes 35 and plate-type collecting electrodes 34, and a condenser unit 28 made up of a series of plates 36 and rods 37 which are of sufficiently large diameter to prevent corona discharges. The collecting electrodes 34 and plates 36 of the condenser are earthed to the casing 30. The high tension current is supplied by a transformer 15 and a mechanical rectifier 4 rotated by a synchronous motor 2. The current is fed by lines 16, 19 and 20 to the rods 36 of the condenser and by means of a distributer 5, also rotated by motor 2, alternately to each of the units 33<a> and 33<b>. The distributer 5 is arranged to act also as a rotary spark-gap, so that impulses of steep wave front are applied to the discharge electrodes. If desired, the units may be fed in parallel, in which case the distributer 5 is replaced by an impulse spark-gap. High frequency oscillations are damped by resistances 14, 18 and chokes 25, 26 and 27, which also regulate the distribution of energy to the discharge electrodes. To prevent deposition of dust, which would alter the characteristics of the electrodes and the capacity of the condenser 28 and impair the efficiency of operation, the discharge electrodes 35 and rods 36 are suspended from supports 38, passing through insulated chambers 39, which are mounted on springs 40 and periodically vibrated by hammers 42. The collecting electrodes 34 and condenser plates 36 depend from transverse supports 43 attached to the sides of the casing. Their lower edges are vibrated by transverse stiff members 44 carrying hammers 45 (shown in Fig. 3), the distance apart of which is slightly greater than the thickness of the plate 34 and reinforcing plates 46. The members 44 are vibrated by means of eccentrics 48 rotated by shaft 49. Two members 44 are preferably used, arranged to jar alternate plates in opposite directions. The capacity of the condenser 28 should preferably be at least as great as the capacities of all the precipitating units to which it is connected.