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

STEAM. 37 A. P. K..M. H. 1 14-7 10,333 33-9 9, 29'4 20,666 67’8 3 44-1 30,999 101-7 4 58’8 41,332 135’6 5 73'5 51,665 169-5 6 88'2 61,998 203-4 7 102'9 72,331 237’3 8 117'6 82,664 271-2 9 1323 92,997 305-1 10 147’0 103,330 339-0 The Theory of Evaporation. 7. If 1 lb. of water at, say, 60° (which is about ordinary summer temperature), is heated up to boiling point (212°), and is then converted into 1 lb. weight of steam at atmo- spheric pressure, the following number of heat units will be absorbed :— First, there will be the heat required to raise the 1 lb. of water to boiling point—viz., 212° - 60° = 152°—then there will be 966 units to convert it into steam. This will make a total of 1,118 units absorbed by the steam in this operation. If, however, the 1 lb. of water is evaporated at a pressure of, say, 10 lbs. above atmospheric pressure, under which condition the temperature of the boiling point is 239° and the latent heat is 946, there will then be required 239 - 60 = 179 + 946 = 1,125 units of heat. In the first case the calculation is— 212 - 60 = 152 units of sensible heat | at atmospheric 966 „ latent heat / pressure. 1,118 units (total) heat.