Download (4MB) - QUT Digital Collections

CANE SUGAR.variety) varies within large limits; hence a ratio which may be quite satisfactoryin one factory will be totally inadequate in another. The writer hasfrequently observed that when the White Transparent cane was being milledin Demerara the megass accumulated, but the supply could not be burned fastenough on the existing grate area to maintain the supply of steam. Thisdifficulty, which may become a great deal more serious than a mere inconvenience,could in the writer's opinion be overcome by the installation of anadditional furnace wherein megass would be fired only when occasion arose.FIG. 223.If this difficulty is really due to differences in the weight of a cubic foot ofmegass, its cure is surely to be found in increased grate area rather than inincreased heating surface in the boilers.Thermal Value of Megass.—The combustible bodies present inmegass are fibre, sugar, glucose and details of other organic bodies; the fibreconsists of cellulose proper, and xylan or wood gum. The heats of combustionof these bodies as determined by Stohlmann and Langbein 3 are, cellulose, 7533B.T.U., sugar, 7120 B.T.U., glucose, 6748 B.T.U. per lb. Taking these heatsof combustion as a basis, and assuming that the fibre has the same fuel value410