Method for producing pure water

• Main Authors: IKUNO NOZOMU, TANAKA YU
• Format: Patent
• Language: Chinese; English
• Published: 23.12.2022
• Subjects: CHEMISTRY; METALLURGY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The method for producing pure water according to the present invention is a method for producing pure water by subjecting water to be treated to a decarbonation treatment under an acidic condition and thereafter to a deionization treatment using a reverse osmosis membrane separation device, in a method for producing pure water, the pH of inflow water flowing into the reverse osmosis membrane separation device and the quality of permeate water flowing into the reverse osmosis membrane separation device are measured, and the pH of the inflow water is adjusted on the basis of the measured pH and quality so that the quality of the permeate water is within a prescribed range, the pH of the inflow water is only changed by a prescribed range. And an operation condition adjustment step in which an average value before water quality change, which is the average value of the water quality of the permeated water from after the pH change to within a predetermined period of time, is adjusted to an average value before wat