GB843782A - Electrostatic precipitators - Google Patents

Abstract

843,782. Electrostatic precipitation. LUEDER, H. Sept. 24, 1956 [Oct. 20, 1955], No. 29075/56. Class 39(1). An electrostatic precipitator comprises a pressure vessel 2 to which gas to be cleaned is supplied through the pipe 4 at a pressure above atmospheric and in which the separator electrodes 6 and 8 are accomodated, an insulated low voltage supply line 21 for the voltage step-up transformer 18, and a pressure-sensitive switch 20 arranged to switch off the current when the gas pressure falls below the operating pressure, e.g. by 10% the separator electrodes 6 and 8 are of conical form and are bent over near their edges so that each edge lies at a greater minimum distance from the neighbouring electrode or electrodes than does the major part of the remainder of the electrode. The edges of the electrodes can be curled over through at least 180 degrees. The edges of the electrodes can be enclosed by puncture-proof insulating layers. The electrodes 6 have earth potential and are supported only at their outer edges where they are spaced by distance pieces 7. The electrodes 8 are at high voltage and are supported only at their inner edges each of which is clamped between two plane annular discs 9 separated from the neighbouring annular discs by rings 11 provided with apertures 10. Detachable pins 12 are provided for locating the electrodes in the radial direction. Two insulating rings 13 and 14 support the two electrode groups 6 and 8. The lowest electrode 6 together with a cover dome 15 which is pressed against this electrode by an abutment 16 when the cap 1 is screwed up forming a cavity 17 containing the transformer 18, a rectifier tube 19 and the pressuresensitive switch 20. The electrode group 6 is connected via earth to the secondary winding of the transformer 18 and the electrode group 8 is connected to the secondary winding of the transformer through the rectifier tube 19. A glow lamp 22 connected through a high resistance 23 to the high voltage electrode group 8 indicates when the field between the electrodes is operating. A wire ring 24 carrying a radioactive preparation serves as an ioniser and is connected through supporting wires to one of the electrodes 8. The gas inlet pipe 4 has an outlet into the vessel 2 which deflects the gas flow into a tangential direction and the gas passes through apertures 26 in the electrodes 6 and then in a cleaned state through the apertures 10 to leave through the pipe 5. The part of the gas that flows between the two lowest electrodes is conducted through apertures 27 in the lower of the two electrodes into the cavity 17 to ventilate it before joining the main gas stream. Any liquid separated from the gas runs down the electrodes and collects in the cap 1 whence it can be discharged through a fitting 29. The distance between the electrodes can be greater than 1 m.m. Packings 30 ensure that the vessel 2 is pressure-tight and packings 31 prevent uncleaned gas mixing with cleaned gas.