| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce variation of the quantity of a dissolved gas due to variation in a flow rate of a raw material liquid, and prevent reduction of the quantity of the dissolved gas even at a low flow rate. <P>SOLUTION: Raw ultra-pure water is made to flow to a hollow fiber module [A], and the flow is divided into the flow of a small flow rate and the flow of a large flow rate at a branch portion b. The flow of the small flow rate is introduced to the inside of a hollow fiber membrane in the hollow fiber module [A] as it is, and the flow of the large flow rate is introduced into bypass pipe lines d1, d2 and d3. Carbon dioxide is introduced into the hollow fiber module [A] from a gas supply port 3, is made to pass through the hollow fiber, and is dissolved into the raw ultra-pure water in the hollow fiber, and ultra-pure water added with carbon dioxide is obtained. At that time, one of the bypass pipes (d) is closed when the flow rate of the ultra-pure water introduced into the device is half or less of that of the initial stage, and then, other opening and closing valves are closed while tracking a specific resistance value of cleaning liquid finally obtained. <P>COPYRIGHT: (C)2013,JPO&INPIT |
