THE DIFFUSION PROCESS. 



steam ; the direct steam becomes condensed in the coil, and pressure is made 

 in the rubber tube by the steam acting on the condensed water. 



Attached to each cell or dipper is the juice heater b ; this is of the verti- 

 cal tube type, exhaust steam being admitted at o, and the condensed water 

 drawn off at p. Communication between diffuser and juice heater maybe 

 made either at top or bottom by the pipes k or c. The main juice circulating 

 pipe is shown at m, the controlling valves or cocks appearing at i. The floor 

 level on which the operator stands is at the line I, all valves and cocks being 

 within easy reach ; g is a small pipe let into the cover of the diffuser to act as 

 an air vent to allow the air to escape when the diffuser is being filled. 



Elevators. The other adjuncts of the diffusion battery which remain 

 to be described are the elevator and charging apparatus ; these are very varied 

 in design and arrangement. In case the canes are sliced on the basement, 

 they are elevated to a floor above the level of the battery by means of an end- 

 less scraper carrier similar to those employed to convey megass to the boilers ; 

 in other cases, the cane cutting machine is placed above the level of the 

 diffusion battery, and the canes are elevated as such, and the sliced cane dis- 

 tributed directly from the cutting machines, 



Charging. The method by means of which the cells are filled with 

 chips varies with the arrangement of the battery ; the latter may be arranged 

 either as a circular or as a line battery. In the former case the cutter is placed 

 about twenty feet above the level of the top of the cells and directly over the 

 centre of the battery, or in case the canes are cut on the basement the chips 

 are elevated to a hopper similarly placed. The hopper or cane cutter is mounted 

 on rollers, so that it can be revolved through a complete circle. The hopper 

 terminates in a shoot, the discharge of which can thus be brought over any cell 

 at will. When the cells are placed in line, the chips cut on the basement are 

 delivered into a truck running on an over-head line, from which pass shoots 

 directing the chips to the diffusers. Line batteries are generally placed in two 

 parallel rows, between which is the platform on which the attendants stand. 



Circulation. The water requisite for the diffusion process is contained 

 in an overhead tank, placed considerably above the level of the diffusers. The 

 circulation of juice throughout the battery is secured by means of the hydrostatic 

 pressure obtained from the head of water in this tank. When it is desired to 

 empty a cell of its liquid contents, this hydrostatic pressure cannot of course be 

 used, and an air compressor, in nearly all cases, forms a part of the plant. The 

 latter is used also in starting the first round of the battery, and afterwards in 

 the regular routine when a cell contains exhausted chips. 



Working of the Battery. In Fig. 136 is given a plan of a 

 twelve- cell line battery, arranged in two rows, showing the pipe connections 

 between cells and heaters, and in Fig. 137 a diagrammatic sketch of a battery 

 intended to illustrate the method of working. Let the battery consist of twelve 



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