| 摘要 |
<p>1,161,282. Spray drying. KNAPSACK A.G. 22 April, 1968 [29 April, 1967], No. 18931/68. Headings BIB and. B2F [Also in Division C1] A nozzle for spray drying apparatus comprises three annular chambers arranged concentrically and comprising inner, central and outer nozzle chambers the oulet openings of which form annular slits, and wherein the axes of the inner and central chambers are directed outwardly: with respect to the nozzle centre axis and the axis of the outer chamber, at least at the outlet end, forms with the axis of the central chamber an angle of 10 to 110‹, preferably 20 to 90‹. The nozzles are useful for spray drying and the manufacture of alkali metal tripolyphosphates or pyrophosphates from alkali metal phosphate solutions or suspensions by spraying through the centre slit of the nozzle into a surrounding flame zone in a tower, while a suitable spraying medium, e..g. air of steam, is supplied to the inner and outer slits. In examples sodium (3) tripolyphosphate and (4) pyrophosphate are prepared by spray drying sodium orthophosphate solutions.</p> |
