The Mechanical Handling and Storing of Material

COKE FROM COKE OVENS 369 Fig. 514. Sectional Plan of Quenching Device shown in Fig. 513. erected and fastened to the ovens. This supports a longitudinal girder b, on the bottom flange of which moves the trolley c that supports the quenching apparatus on a swivel and two chains, in such a manner that it can be easily conveyed to any of the ovens of the battery which may be ready for pressing. The water main d has a number of T-pieces with valve and hose connection, so that the main may be connected with the apparatus wherever wanted. The arrangement of the sprinkling pipes is seen from the illustration, and consists of six or more pairs of pipes according to the height of the ovens, the middle and the top one of a larger diameter; the former because they serve as a connec- tion to the main, and the latter for the sake of strength, and also in order to give an extra copious supply of water on top of the coke cake, where it is always more or less divided or open, as this is the best way of getting quenching water to the interior of the coke before breaking it up. When the apparatus is in position and connected to the main the oven door is lifted, and the coke is pushed slowly through the quenching apparatus. It has already been mentioned that the hearth must have a slight fall, away from the ovens. This is particularly necessary when this form of quenching is adopted, as it necessitates the use of a large quantity of water in very close proximity to the ovens, and|it is, therefore, advisable to give an extra gradient to the hearth of not less than 10 per cent, to prevent the water from entering the ovens. It has been found that if the coke is pressed at a speed of 6 ft. per minute the automatic quenching can be done thoroughly. If the mechanical appliances of the ovens do not permit of so slow a speed, it is advisable to push for a distance equal to the reach of the quenching pipes; then stop and quench for one minute ; then push again, and so on. The quenching of the coke in this manner saves very considerably in labour, and the appearance of the coke is excellent; on the other hand, it must be mentioned that the water-quantum used is two to three times as Figs. 515 and 516. The Darby Coke Quencher. much as in the old-fashioned way, and in con- sequence of the slow pressing the rod and head are exposed to the temperature of the oven for a considerable time, so that even if they are made of cast steel they will require more frequent renewal. In spite of these, the advantages are of such importance that mechanical quenching processes are largely used, particularly in Great Britain. I'he well-known Darby coke quencher is shown in Figs. 515 and 516 ; its special feature is provision against the access of the atmosphere to the coke. The appliance consists of the main pipe a, which branches off into smaller pipes b. To exclude the air plates c are employed to close the space between the pipes, and the spray of water passes through a great number of small nozzles which are screwed into the pipe, and extend