784
MODERN GASWORKS PRACTICE
heat ni the blows, by leading blow gases into the carbonizing retort, or applied outside in the retort; (3) the sensible heat in the producer gas, by leading producer gas into the caibonizing retort, or applied outside the retort; (4) the combustion of producer gas externally to the carbonizing retort; (5) high-pressure or superheated steam applied outside the retort.
The effect of using hot superheated water gas for the carbonizing process is to give a better quality of gas. When the sensible heat of producer gas or the heat of the combustion of producer gas is used, the quality of gas made is rednced.
Plant for carrying out a process of this type comprises, according to this invention, a generator, a vertical retort, separate from the generator, wliose outlet is above the generator and in proximity thereto, and means for admitting gases from
Fig. 472.—TTet/ps’ Mixed Gas Plant.
the generator into the retort. The generating element comprises in one structure a fuel chamber and a superheater, while the retort is of inverted tee-shape, the base, or horizontal portion of the tee being directly above an inlet to the fuel chamber. The plant is shown in Fig. 472. The generators are shown at A, the superheaters at B, and the retorts at C. The air-blast passes into the generators, down through the first superheater, and up through the second. Thence through pipes (E and F) to a boiler which generates the necessary steam. Steam is then introduced in one superheater at the top and, passing through the chequer work, reaches the generator. It travels through this in a downward direction under the arch H dividing the generators, and up through the second generator ; then on through the other pair of superheaters into the mains E and G, which lead to the retorts. Here the “ blue ”