Zigzag process

Figure 5.20 The reversal points of a zigzag process can be specified anywhere in the sound and can be of variable length...

The filter usually has an endless cloth, traveling intermittently between the plates via roUers, to peel off cakes. Unfortunately, if the cloth is damaged anywhere, the whole cloth must be replaced, which is a difficult process. Each time the filter cloth zigzags through the filter, the filtering direction is reversed this tends to keep the cloth clean. Most of these filters incorporate membranes for mechanical expression, and cakes sometimes stick to the membranes and remain in the chamber after discharge. Some vertical filters are available with a separate cloth for each frame. The cloths maybe disposable and such filters are designed to operate with or without filter aids. 

H. H., Mixing processes in a zigzag microchannel finite element simulations and optical study. Anal. Chem. 74 (2002) 4279-1286. 

Fig. XIV. p. 93, is interesting it is an apparatus for rectifying spirits, by distilling, and liquefying only the most volatile portions of the distillate. The spirituous liquor was heated, and the vapours caused to traverse a long zigzag tube, wherein the less volatile portions condensed to liquid, which flowed back into the vessel the vapour then passed into another vessel, and then through a second zigzag tube, and was finally cooled by water, and the condensed liquid collected. This apparatus was the forerunner of that used to-day, for effecting the separation of liquids which boil at different temperatures, by the process called fractional distillation.

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