摘要 |
In an process and assembly to produce drinking water, water is passed at intervals from the public supply (2) to a storage vessel in which it is decalcified. The water is subdivided by reverse osmosis using a semipermeable membrane (7) at high melt pressure into (i) decalcified water and (ii) water with an enhanced dissolved calcium content. The novelty is that: (a) the decalcification is effected by the semipermeable membrane (7); (b) during periods in which no flow of water takes place, the water around the membrane is pressurised to more than 2 bar, and carbon dioxide gas is introduced to water above the semipermeable membrane; and (c) carbon dioxide liberates the calcium deposits which are then rinsed off by water at between 4 and 8 bar. |