| 摘要 |
PROBLEM TO BE SOLVED: To produce high quality pure water at low costs by adjusting raw water passed through each apparatus at a specified temperature. SOLUTION: Water heated by a recovered heat exchanger 6 in advance is heated by a heater 7 such as a heat exchanger. In order that raw water is heated and passed through a degassing apparatus 3, an RO apparatus 4, and an ion exchange desalting apparatus 5 at 35-80 deg.C, heating in the heater 7 is preferably done so that the temperature of the water at the outlet of the final apparatus 5 is at least 35 deg.C. When the temperature of the raw water is below lower 35 deg.C, the effect of improving an ion exchange/removal ratio by the removal of volatile organic substances, the poor solubility of silica and boron compounds, and the ionization tendency of silica, boron, and other substances can not be obtained sufficiently, and when the temperature exceeds 80 deg.C, ion exchange resins, an RO membrane, and others are deteriorated by heat, and water quality can be lowered by eluted substances from these. |
