GB476332A - Improvements in means for treating fuel gases - Google Patents

Abstract

476,332. Treating gases with electrical discharges. KOPPERS CO. April 4, 1936, No. 10050. Convention date, Oct. 9, 1935. [Class 39 (i)] Apparatus for stabilizing coal distillation, &c. fuel gases against the formation of resinous compounds caused by the presence therein of oxides of nitrogen as described in Speci. fication 473,009, [Group XII], comprises a treating chamber 13, Fig. 5, provided with fixed parallel electrode plates 7, 12 arranged in two series with the plates of one series alternating with those of the other, at least one of the series being insulated. As shown, one set of plates 12 is grounded through the casing 13 and are plane, while the plates of the other set 7 are mounted on insulators 9 disposed in housings 20 heated by steam coils 21, and provided with rows of discharge points 3 equally spaced apart from each other and separated from the plates 12 by an air gap through which the gas passes. The plates are connected in a high potential circuit such as to produce a brush discharge without the formation of an arc. It is stated that the optimum effect with the minimum risk of arcing is obtained when the point electrodes are positively charged and when a source of alternating potential is used, the circuit is completed through pairs or pairs of groups of the electrodes, and the gas under treatment so that the electrodes are charged alternately positively and negatively; alternatively a circuit using double half-wave rectification may be used. In the arrangement shown, the gas traverses two groups of treating elements arranged in series. Flushing of the electrodes is obtained in any of the usual ways and in the construction shown liquid, such as oil, is sprayed by nozzles 65 into the gas in advance of each treater element to provide the flushing liquid. Instead of the point electrodes being insulated and the plane electrodes grounded, the opposite arrangement may be employed. One method of constructing the point electrodes is shown in Fig. 1, and consists in bending up triangular points from a sheet metal plate which is attached to a strong metal supporting plate 1 on one or both sides. To provide drainage where necessary, the points are inclined. An alternative construction is shown in Fig. 3, in which pointed pins 3 are driven with a tight fit through holes in the supporting plate 2. The pins have shoulders 4 and wedging bosses 5, and in the assembled arrangement the shoulders and pins are disposed on opposite sides of the plate 2 in alternate rows to avoid distortion of the plates. The pins are disposed so that three adjacent pins form an equilateral triangle.