| 摘要 |
PURPOSE:To permit the continuous production of high-purity water to be widely used in a semiconductor production plant, etc., by providing means for adding a sterilizer and pH adjusting agent, the 1st reverse osmosis membrane separator, means for adding hydrazine, the 2nd reverse osmosis membrane separator, etc. CONSTITUTION:The sterilizer and/or pH adjusting agent are added to the raw water pretreated with activated carbon, etc., in the means 12, 13. The raw water added with the sterilizer and/or pH adjusting agent is subjected to a reverse osmosis membrane treatment in the 1st reverse osmosis membrane separator 2. The hydrazine is added to the permeated water of the separator 2 in the succeeding means 16 and the permeated water of the separator 2 added with the hydrazine is further subjected to the reverse osmosis membrane in the 2nd reverse osmosis membrane separator 3. The permeated water of the separator 3 is taken out in the system 18 and the concd. water of the separator 3 is returned to the raw water supply system of the separator 2 in the system 10. As a result, the high-purity water widely used in the semiconductor production plant, etc., is continuously produced. |
