WATER TREATMENT PROCESS Russian patent published in 2001 - IPC

FIELD: water treatment. SUBSTANCE: invention relates to ion-exchange technology for desalting and softening of water with simultaneous reduction of water alkalinity, which can be applied in powering engineering for production of high-quality conditioned water appropriate as heat carrier. For that, initial water is desalted on H- filters by consecutively passing it through carboxyl cationite and sulfonic cationite, after which water is treated on OH-filters. Softening is performed by consecutively or concurrently passing water through carboxyl and sulfonic cationites in two steps: desalted water is first passed through cationites depleted in water desalting operation until hardness ions slip through sulfonic cationite and then water is passed through the same cationites additionally treated with spent OH-filter-regeneration solution, which is passed successively through carboxyl and sulfonic cationites. Exhausted H-filters are regenerated by passing regeneration acid solution first through sulfonic cationite and then through carboxyl cationite. Working capacity of cationites is further increased by treating carboxyl cationite with acid spent H-filter-regeneration solution from previous regeneration operation before acid regeneration of carboxyl cationite filter. Invention allows sodium ion level in desalted water to be reduced by 80 times and alkalinity in softened water to be stabilized and reduced to values 0.34-0.4 mg-equ/cu.dm. Working capacity of cationites increases by 2.6-3.4 times resulting in 2.6-3.8-fold increase of summarily produced desalted and softened water. EFFECT: essentially increased water treatment efficiency. 2 cl, 1 dwg, 1 tbl, 3 ex