METHOD FOR OPTIMISED DESALINATION OF AN ALKALINE INDUSTRIAL EFFLUENT WITH PRESSURISED CO2

To provide a treatment method of industrial waste water containing calcium for the purpose of removing the whole or a part of calcium from the industrial waste water.SOLUTION: In a treatment method of industrial waste water containing calcium, the waste water 10 to be treated is introduced to a zone equipped with a settling tank 12; a part of the waste water taken out at an outlet of the settlement tank, that is 3-25%, preferably 5-10% of a stream flown from the settling tank, and usually a part 13 taken out at the downstream of a high pressure pump 9 operated at a pressure of 8-10 bars, is split; at least one injection 15 of CO2 gas into a split stream is performed; a pH value of the split stream is lowered to 4-6.8, preferably 4.5-6,; and the treated split stream is returned to the initial waste water and reaches the a settling tank body in the settling tank.SELECTED DRAWING: Figure 3