Method of purifying sewage efluent and apparatus therefor

Abstract

Abstract POLLUTED AQUEOUS LIQUID SUCH AS SEWAGE OR INDUSTRIAL WASTES WHICH CONTAIN ORGANIC MATERIALS WHICH ARE ANIONIC POLYELECTROLYTES AND THEIR PRECURSORS, INCLUDING COMPOUNDS OF PHOSPHORUS, NOTROGEN, CARBON OR OTHER ELEMENTS, AND A DISSOLVED POLYVALENT METAL SUCH AS ALUMINUM, CALCIUM OR MAGNESIUM AND CHLORIDE IONS IS ELECTROLYTICALLY TREATED BY CIRCULATING THE LIQUID PAST THE CATHODE AND UPWARDLY WITH THE CATHODE EVOLVED HYDROGEN TO RAISE THE PH OF THE CIRCULATING LIQUID AND PRECIPITATE, FLOCCULATE AND FLOAT THE ALKALINE EARTH PRODUCTS OF THE PRODUCTS OF THE ORGANIC MATERIALS AND THE OTHER POLLUTANTS. THE FLOATED MATERIALS ARE SEPARATED FROM THE LIQUID, AND THE LIQUID SO DEPLETED THEN FLOWS DOWNWARDLY, AND ANY UNFLOATED MATERIAL IS RETURNED TO THE CATHODE UPWARD LIQUID FLOW, AND AT LEAST PART OF THE LIQUID IS WITHDRAWN FROM THE LOWER PART OF THE DOWNWARD FLOW AND IS EXPOSED TO THE OXYGEN AND CHLORINE BUBBLES EVOLVED AT THE ANODE WHICH IS IMMERSED IN A QUIESCENT BODY OF THE LIQUID COMMUNICATING ELECTRICALLY WITH THE CATHODE. ALTERNATIVELY THE CATHODE AND ANODE ARE POSITIONED IN RESPECTIVE LONGITUDINAL CHANNELS, SEPARATED BY MACROSCOPICALLY PERFORATE PARTITION WHICH PERMITS IONIC CROSSFLOW BUT INHIBITS LIQUID CROSS FLOW. THE INFLUENT TRAVERSES THE CATHODE CHANNEL AND THE FLOCCULANT SKIMMED FROM ITS SURFACE AND THEN TRAVERSES A SETTLING TANK AND THE ANODE CHANNEL TO BE TREATED AS ABOVE. THE CATHODE IS FORMED OF A CORROSION RESISTANT METAL HAVING A THIN COATING OF THE ELECTRICALLY NON-CONDUCTING OXIDE OF THE CATHODE METAL AND IS ADVANTAGEOUSLY TITANIUM. THE CELL INCLUDES A BAFFLE STRUCTURE WHICH DELINEATES AN UPWARD FLOW FIRST PASSAGE ABOVE THE CATHODE JOINED AT ITS TOP TO AN ADJACENT DOWNWARD FLOW PASSAGE WHICH COMMUNICATES AT ITS BOTTOM WITH THE FIRST PASSAGE AND WITH AN UPWARD FLOWING OUTER DISCHARGE CHAMBER INTO WHICH GASES RISE THROUGH SMALL OPENINGS FROM AN UNDERLYING CHAMBER CONTAINING THE ANODE IN A QUIESCENT BODY OF THE LIQUID.

Inventors

• 👤 B Greenberg

Bibliographic Details