A Practical Manual On Sea Water Distillation
With A Description Of The Necessary Machinery For The Process

130 SEA WATER DISTILLATION. (5) Brine Discharge. 143. The brine discharge, by which the brine level is governed, will now be dealt with. 144. The brine discharge may be either constant or intermittent. By constant is meant a gradual escape of the brine, and by intermittent a sudden emptying away of the entire brine from time to time ; on board ship it appears to be at the commencement of each watch. In the interval the brine level is kept by hand—that is, by partially opening the brine cock, according to the indica- tions of the gauge glass and salinometer. 145. The advantage of an automatic constant discharge of brine is manifest. There is no objetcion to turning out all the brine periodically, but using the brine cock so as to work to a level that requires careful adjustment is naturally less efficient than a brine discharge that auto- matically regulates the brine level. It is stated to answer all right when the risk is pointed out. If so, it would hardly appear necessary to have expensive appliances to regulate the feed, and so many conditions specified, if this impor- tant matter is left to a casual feeding of the evaporator by hand. 146. The brine discharge, when the evaporator is working with a secondary pressure (that is, a pressure in the steam-room) at or just above that of the atmo- sphere, can be arranged as shown in Fig. 15, which re- presents an evaporator with casing (E)—the coils are not shown, so as not to interfere with the explanation of the brine level—and pipe (P), which rises from near the bottom of the casing to the outlet (B). The feed-water enters at (F), and the secondary steam evaporated therefrom escapes at (S) through a small hole of a size suitable to