Reverse osmosis membrane device operation management method and reverse osmosis membrane treatment system

摘要

[PROBLEMS] To suppress the generation of scale in a reverse osmosis membrane device and maintain stable operation for a long time even under low water temperature conditions (water temperature 5-10 ° C.) without requiring pH adjustment or addition of a scale dispersant. To do. The operation of the reverse osmosis membrane device is managed based on the concentration of aluminum ions and / or iron ions in the feed water and / or concentrated water of the reverse osmosis membrane device. The decrease in the flux of the reverse osmosis membrane due to the silica scale is greatly influenced not only by silica but also by coexisting aluminum ions and iron ions. In order to stabilize the long-term operation of the reverse osmosis membrane device, it is necessary to appropriately control the aluminum ion and / or iron ion concentration in the feed water and / or concentrated water. [Selection] Figure 1