Gas Producers

Gas Producers, In many metallurgical operations gaseous fuel is employed as a source of heat. In these cases the gas does not require to be of the same degree of purity as when used for purposes of illumination, and is usually manufactured by the distillation of coal-slack, etc., brought about by the combustion of part of the coal itself. The manufacture is carried on in what are known as Producers, many forms of which are in use - e.g. Siemens', Casson's, etc, They all consist of large chambers of fire-brick, or iron lined with fire-brick, provided with hoppers for the introduction of the coal, etc., in which the fuel is burned in an insufficient supply of air. A blast of steam is also usually blown through, which serves not only to increase the pressure of the gas and produce a draught, but also causes a greater quantity of gas to be formed. The products then pass into large iron tubes or culverts, leading usually direct to the furnace in which the gas is to be employed. Producer gases thus prepared consist chiefly of various hydrocarbons, resulting from the distillation of the coal, carbon monoxide (CO), resulting from the incomplete combustion, and hyelroyen present owing to the decomposition of the steam. They are usually mixed with air and heated before admission into the furnace, as by these means a higher temperature is obtained.