METHOD OF PURIFYING UNDERGROUND WATER Russian patent published in 1997 - IPC

FIELD: water treatment. SUBSTANCE: invention relates to methods for deep purification of underground water for husbandry and drinking water supply, and in particular, to methods of cleaning natural water from iron, manganese, iron-phosphate complexes, hydrogen sulfide, carbon dioxide, methane, oil impurities, phenols, and nitrogen-containing substances. Essence of invention resides in deep treatment of underground water, including degassing; two-step filtration with step-by-step washing and using, as first-step filter charge, inert material and, in the second step, sorbent; and sterilization. Degassing is fulfilled with bubbling agency. First-step filtration is accompanied with water-air washing of filter charge, and second-step filtration is carried out from above downward through filter charge composed of two layers: sorbent and ion-exchange material. Washing is conducted in countercurrent: ion-exchange material - sorbent. The former is regenerated with sodium chloride solution. Sterilization is accomplished by UV irradiation. Bubbling is carried out with air intake 3-10 cu.m per 1 cu.m of water. Water-air washing is performed in three steps. Sorbent and ion-exchange material are disposed in the same apparatus. EFFECT: enhanced efficiency in treating water. 4 cl, 1 dwg, 1 tbl