Modern Gasworks Practice

LO K) MODERN GASWORKS PRACTICE tar or oil. Speed for speed the horizontal types absorb the larger amount of power, but owing to the very much. greater rate at which the vertical machines travel they are usually rather more extravagant in this direction. The following figures (re-lating to the Kirkham, Hulett and Chandler washers) show the approxi-mate powers required for various sizes of machines; but wlien installing driving plant for this purpose it is advisable to allow some further margin (say 20 per cent.) for con-tingencies. Fia. 327.—Dempstbr-Fjsld Washer Spraying Cones. JFig. 326.—The Dbmpsteb-Fbld Centrifugal Washek. Cubic feet. Horizontal. Vertical. 500,000 per diem . 3 h.p. .. 4 h.p. 1,000,000 „ . 4 h.p. . . 5 h.p. 2,000,000 „ „ . 5 h.p. . . 7 h.p. 3,000,000 „ „ . 6 h.p. . . 10 h.p. From this it will be seen that if elec-trical energy is used the cost per day for driving a 3 million cubic feet vertical machine would amount to 20s., or about 0’08cZ. per 1,000 cubic feet of gas treated, or Id. per ton of coal, with electricity at 1 ’5d. per unit.