| 摘要 |
<p>PURPOSE:To effectively remove volatile silicon from water in a volatile state by subjecting raw water containing volatile silicon to aeration or degassing treatment under a condition of specific LV (linear velocity). CONSTITUTION:In an ultrapure water purifying apparatus where a cation exchange resin tower 1, a decarbonation tower 2, an anion exchange resin tower 3, a reverse osmosis membrane device 4, a mixed bed ion exchange resin tower 5, an ultraviolet irradiation device 6 and a polisher 7 are successively connected by pipings, volatile silicon removing devices 9, 10 are respectively connected to the rear stage of the ultrafiltration membrane device 8 and the outlet piping of the polisher 7. The volatile silicon removing devices 9, 10 are constituted of aeration tanks, degassing towers, vacuum degassing towers, air bubble towers and degassing members and treat volatile silicon-containing raw water under such a condition that LV (linear speed) becomes 0.01-100m/h at the time of treatment. At this time, inert gas is added to water to be treated or an atmosphere.</p> |
