Percolation through granular carbon

In the soft drink industry it has become common practice to super-chlorinate water used in processing. It is then percolated through a bed of granular activated carbon to remove any residual chlorine by catalytic action and also to adsorb any remaining taste. 

Bone char and granular carbon are generally used in fixed beds or in cylindrical columns 20 to 25 feet high and about 10 feet in diameter. Some recent systems percolate liquor upward or downward through a stationary bed of adsorbent or by counter-current flow of liquor and adsorbent (CAP or continuous adsorption process). (See below. Fig. 9.17.)... 

Bone char, the forefather of activated carbon, has long been in the forefront of adsorbents for sugar refining. The granular char is placed in columns through which the hot syrups percolate until the char is exhausted, as evidenced by the appearance of color in the filtrate. The bone char is then regenerated by thermal means for re-use.3... 

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