Modern Gasworks Practice

THE HORIZONTAL RETORT BENCH 93 inch, the average efficiency increases as the steam pressure is reduced, so that with steam at 20 Ib. the figure rises to 71 per cent. Another type of waste-heat boiler is shown in Fig. 39. The latest form of waste-heat boiler (Fig. 40) is that introduced primarily for use with. the Glover-West system of vertical retorts. F. W. J. Belton,1 at Macclesfield Gaswerks, has found that by Fig. 39.—Waller’s Waste-Hbat Boiler. utilizing th.e waste heat from vertical retorts h.e has been able to recover for sale an additional 1-5 cwt. of coke per ton. of coal carbonized. A boiler fitted to a retort setting carbonizing 18 tons of coal per day evaporated. on. an. average 4501b. of water per h.our, th.e pressure of th.e steam raised being 100 1b. per square inch. The steam is used 1 In a letter to the author, August, 1920.