Table Headings-- A: Blast Furnace. B: Producer. C: Mond. D: Mixed (Fichet). E: Water (Stache). F: Wood (Riché). ________________________________________________________________________ | | Gas. |_________________________________________________ | | | | | | | A. | B. | C. | D. | E. | F. ______________________|_______|_______|_______|________|________|_______ | | | | | | Nitrogen and oxygen | 60 | 59 | 42 | 50 | 5 | 1 Carbon monoxide | 24 | 25 | 11 | 20 | 40 | 29 Carbon dioxide | 12 | 5 | 16 | 7 | 4 | 11 Hydrocarbons | 2 | 2 | 2 | 3 | 1 | 15 Hydrogen | 2 | 9 | 29 | 20 | 50 | 44 |_______|_______|_______|________|________|_______ | | | | | | | 100 | 100 | 100 | 100 | 100 | 100 |_______|_______|_______|________|________|_______ Calorific value | | | | | | in calories. | 950 | 1,100 | 1,400 | 1,300 | 2,400 | 2,960 Average weight of a | | | | | | cubic meter in kilos| 1.30 | 1.1 | 1.02 | 1.05 | 0.680 | 0.824 Or of a cubic foot | | | | | | in pounds | 0.008 | 0.007 | 0.006 | 0.0068 | 0.0042 | 0.0051 ______________________|_______|_______|_______|________|________|_______
Blast-furnace gas has been used for generating power by means of gas-engines for about ten years. At the present time it is used in engines of very high power, a discussion of which engines more properly belongs to a work on metallurgy, and has no place, therefore, in a manual such as this.
Producer-gas, in the true sense of the term, is generated in special apparatus either under pressure or by suction in a manner to be described in the following chapters.
Mond gas is produced in generators of the blowing or pressure type from bituminous coal, necessitating the employment of special purifiers and permitting the collection of the by-products of the fractional distillation of the coal. Mond gas plants are, therefore, rather complicated and can be advantageously utilized only for large engines. More exhaustive information can be obtained from the descriptions published by the builders of Mond gas generators.
Mixed gas is generated in apparatus arranged so that the retort is kept at a high temperature, thereby producing a gas richer in hydrogen than that made by producers. It should be observed that in practice the generators at present used yield a producer-gas, the calorific value of which fluctuates between 1,000 and 1,400 calories per cubic meter (3,968 to 5,158 B.T.U. per 35.31 cubic feet); and the composition varies accordingly, in the manner that has already been indicated in the tables for producer-gas and mixed gas. There is no necessity, therefore, for drawing a distinction between these two qualities of gas.