METHOD FOR DECIDING CAPACITY OF ION-EXCHANGE RESIN, MANUFACTURE OF ULTRAPURE WATER USING THE ION-EXCHANGE RESIN AND, MANUFACTURE OF THE ULTRAPURE WATER

摘要

PROBLEM TO BE SOLVED: To obtain an apparatus for manufacturing ultrapure water for simply conducting a water flow test of ion-exchange resin (CP) by effectively judging performance of the CP and accurately measuring impurity concentration in the water. SOLUTION: A bypass line 12 for detouring ion-exchange resin CP is provided in a sub-system of the apparatus for manufacturing ultrapure water. Testing CP is filled in a column 14 mounted on the way of the line 12, and primary ultrapure water exceeding 1 liter/min is continuously fed to the CP. After the continuous feeding for 20 hours or more, a dip test is executed. In this case, a testing cleaning wafer 21 is dipped in a pure water tank 11 for about three minutes, spinner-dried, and further analyzed by an AAS. The CP in which Na concentration on the surface of the wafer is abruptly lowered is decided as an acceptable product, which is used to manufacture ultrapure water. The Na concentration in the pure water can be controlled to about 2ppt.