| 摘要 |
1,209,779. Evaporation of saline water or sewage effluent. W. R. GRACE & CO. 20 Nov., 1967 [23 Nov., 1966], No. 52766/67. Heading B1B. [Also in Division C7] To inhibit scaling, when saline water, such as sea (water, or sewage effluent, is heated in an evaporation plant, from 0.1 to 20 p.p. of a polymer of methacrylic acid or an alkali metal salt thereof, having an average molecular weight of 1000 to 500,000 and calculated as Na polymethacrylate, is added to the water. The inhibitor may be added in a vaporization zone, in a pretreating zone, or may be incorporated in feed water, suitably being added as an aqueous solution containing at least 1% by weight of inhibitor and optionally anti- 'foam agents, corrosion inhibitors and oxygen scavengers. Evaporation may be carried out at 85‹F to 350‹F, in flash evaporators, or in film evaporators (falling-, rising- or wipedfilm), or in basket-type evaporators. |
