PROCESS AND DEVICE FOR ELECTROCHEMICAL PURIFICATION OF SEWAGE Russian patent published in 2000 - IPC

FIELD: electrochemical treatment of sewage carrying emulsified and colloid-dispersed contaminants. SUBSTANCE: process is conducted under conditions producing maximum possible saturation of liquid with electrolysis gas bubbles 0.3-0.9 A/m² in diameter. Density of current on hydrophobic insoluble electrodes located in lower part of central cylinder is kept within limits of 200-400 A/sq.m. Reynolds number Re in stream of purified liquid going upwards is kept within limits from 2000 to 2700. After this stream is subjected to compression over area of flow section providing for flow of stream with Reynolds number Re from 3500 to 4500 with subsequent abrupt expansion. As result of such combination of conditions enlargement of particles-contaminants, their entrainment by foam and separation in comparatively coarse filters take place. After expansion stream is passed through second electrode unit whose electrodes are placed horizontally and are made of porous unwoven filtering material. Density of current across these porous horizontal electrodes is maintained within limits of 100-200 A/sq.m and velocity of liquid stream is kept on condition to obtain Reynolds number in bounds of 120-200. Proposed process is realized in electric flotation device that has cylindrical body with lid and lower body placed uniaxially. Lower part of lower body carries vertical anodes and cathodes made insoluble from expanded carbon material. Upper part of lower body has narrowing with 20-40 times reduction of flow section behind which expansion chamber is situated. Inlet of water to be purified is located below mentioned electrode unit and outlet of purified water is located in lower part of upper body. Perforated horizontal anode and cathode made of filtering current-conducting material are positioned at bottom of ring space formed by upper and lower bodies. EFFECT: updated process of purification of sewage with achievement of high degree of purification. 5 cl, 2 dwg, 2 tbl