THE HORIZONTAL RETORT BENCH 109
are still employed with satisfactory results. In faet, two of the company’s works are solely equipped with. inclined retorts.
CONTINUOUS HORIZONTAL RETORTS
A principle has recently been introduced whereby horizontal retorts may be operated continuously on lines approaching the continuous vertical retort. The system is tlie invention of Messrs. J. West and W. Wild, and the method of operation will be readily understood by reference to the accompanying illustrations.
One of the earliest attempts to render the horizontal retort continuous in action was made about the middle of last Century when the principle of the Archimedean
screw was em-ployed. A screw conveyor was fitted to the interior of each retort, and as the coal was fed into the inlet end it traversed the hot space and was intended to come out in the form of coke at the op-posite end of the retort. At this time the heats e m-ployed for carboni-zation were essen-tially 1 o w and would not neces-sarily preclude the use of a conveyor of the kind, but in practice the scheine
Fig. 55.—West and Wild’s Continuous Horizontal Retort System. (Original design.)
was found impracticable and was ultimately abandoned. In 1889 Yeadon and Adgie came forward with a fairly promising idea which involved the use of a revolving retort. The retort was of conical shape, mounted with its axis horizontal and carried on suit-able bearing rollers. The middle length was enclosed in a furnace which, by external heating, maintained the temperature of this portion at about 1,000° C. The coal entered at the smaller end of the cone, being taken through a small cylinder rendered gas-tight by means of a spiral blade device. At the larger end was an ascension pipe through which the gas passed, while at the same end was provided a channel into which the coke feli, passing out by a gas-tight cylinder similar in design to that employed for admitting the coal. The coke obtained, however, was of extremely poor quality, being little better tlian breeze. Probably, on the latter account the