PROCESS AND EQUIPMENT FOR PRODUCTION OF WASH WATER CONTAINING DISSOLVED GAS, AND CLEANING EQUIPMENT

摘要

A process for the production of wash water in which a specific gas is dissolved, characterized by comprising dissolving a specific gas in water under pressurizing at a pressure exceeding atmospheric pressure to form an aqueous solution of the gas having a gas concentration not lower than the solubility of the gas at atmospheric pressure and depressurizing the solution to remove part of the dissolved gas; equipment for the production of wash water in which a specific gas is dissolved, which comprises a gas dissolution unit (14) for dissolving a specific gas in water under pressurizing at a pressure exceeding atmospheric pressure and a gas partial-removal unit (15) of depressurizing the resulting solution from the unit (14) to a pressure lower than the pressure at dissolving the gas to remove part of the dissolved gas; and cleaning equipment in which the wash water is used. Wash water in which a gas is dissolved in a desired concentration can be produced safely and without any depressurizing system such as vacuum pump, while the wash water permits the recovery of water and a specific gas from spent wash water and the reuse of both. The wash water is suitably usable in cleaning electronic components necessitating high cleanliness and so on.