| 摘要 |
PROBLEM TO BE SOLVED: To provide a pure water production system which can prevent silica deposition onto a reverse osmosis membrane even when the silica concentration of raw water is high, in the pure water production system using a reverse osmosis membrane device. SOLUTION: The pure water production system 10 includes a water softening device 11, an alkali addition means 12 which alkalizes water flowing through a water supply line, a low silica removal rate reverse osmosis membrane device 15 which uses a low silica removal rate reverse osmosis membrane having a silica removal rate of 90% or less and is installed at the forefront stage of reverse osmosis membrane devices, and a high silica removal rate reverse osmosis membrane device 16 which uses a high silica removal rate reverse osmosis membrane having a silica removal rate exceeding 90% and is installed at the rear stage of the low silica removal rate reverse osmosis membrane device 15. COPYRIGHT: (C)2011,JPO&INPIT |
