METHOD FOR PROVIDING ULTRAPURE WATER

• Main Author: KEARY, James
• Format: Patent
• Language: English
• Published: 14.11.2019
• Subjects: CHEMISTRY; METALLURGY; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

A method of sanitising a section of a water purification apparatus able to provide a purified water stream having a conductivity of less than 1 μS/cm at 25° C. to a dispense outlet, the water purification apparatus having a purified water recirculating section including at least one deioniser and the dispense outlet, comprising at least the steps of: (i) providing recirculation in the purified water recirculating section; (ii) providing ozone-generation in the purified water recirculating section after the at least one deioniser; (iii) allowing the ozone to circulate around the purified water recirculating section to sanitise at least the part of the purified water recirculating section having the dispense outlet; and (iv) using ultra violet radiation to stop the sanitising prior to the at least one deioniser. The use of in-line generated ozone to sanitise a water purifying stage has a number of advantages, including in particular automation, directly dissolved ozone, being environmentally friendly compared to the use of previous sanitisation materials such as chlorine tablets, and the avoidance of requiring any rinsing and flushing steps or cycles, with its attendant waste of water going to a drain only.