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

MULTIPLE DISTILLATION. 179 Primary water (for 1 ton of coal), Secondary water, 80 per cent, of 10 tons (free of coal),__________________ Tertiary water, 80 per cent, of 8 tons (also free of coal), .... 10 tons. 8 „ 64 „ Total water (for the 1 ton of coal), 24’4 tons. (4) Quadruple Distillation. 19. Obviously by extending the principle—i.e., by adding a third evaporator—an additional 80 per cent, of 6-4 or 5’12 tons is distilled. This would be quadruple distillation. By adding a fourth evaporator the yield is 80 per cent, of 512 tons or 4-036. This would be Quin- tuple distillation. A fifth evaporator would yield 80 per cent, of 4’036 or 3'276 tons, and be Sextuple distillation. Economy Comparison. 20. These progressive gains from 1 ton may be sum- marised as follows :— Single Distillation =10 tons. Add, . 8 „ (^0% 10 tons). Double Distillation = 18 Add, 6-4 ,, (80% of 8 tons). Treble Distillation = 244 >5 Add, . 512 ,, (80% of 6'4 tons). Quadruple Distillation = 29'52 5 ? Add, 4-096 „ (80% of 5'12 tons). Quintuple Distillation = 33616 J? Add, 3-276 „ (80% of 4’096 tons). Sextuple Distillation = 36-8928 „ all from 1 ton of coal.