| 摘要 |
<p>1,235,760. Heating saline water; flash-distillation plant. MONTECATINI EDISON S.p.A. 5 Dec., 1968 [6 Dec., 1967; 12 Nov., 1968], No. 57712/68. Heading B1B. Saline water, such as sea water, flows down column 10 (Fig. 1) and up column 11 which is heated at the base e.g. by injection of steam at 14; successive evaporation of some of the water takes place as the saline water rises up column 11, and the vapours collect under plates 17 and pass through apertures 13 into column 10 where the vapours condense in the downflowing saline water thereby heating it so that salts such as calcium sulphate are precipitated and can be withdrawn through outlet 22. Softened water is collected in vessel 7 which is at a lower level than vessel 6 so that the flow of water takes place by pressure difference. Air is withdrawn from the apparatus by ejector 8. The two columns may be arranged at concentric tubes. Fig. 6 shows a plant wherein a heat-transfer apparatus 30 of the type specified above is associated with a multi-stage flash evaporator comprising one flash section B at high temperature, a heater 31 and two flash sections A and C at low temperature. Saline water is introduced into the plant through inlet a; and desalinated water, which is collected in condensate trays below coils 32, 36, 37, is withdrawn through outlet c. Calcium sulphate is discharged through outlet d. Brine is withdrawn through outlet b; some of this brine is discharged and the remainder is recycled to the flash sections by pump 35. Fig. 7 (not shown) illustrates a multi-stage flash evaporator associated with a heat-transfer apparatus comprising two units (30') and (30").</p> |
