Another twist in filtration for high-purity and other systems

摘要

Typically granular activated carbon (GAC) is used in a packed bed or is combined into a filter media. To incorporate these carbon granules into a filter media requires adhesives or a starch additive to keep the carbon from washing out; alternatively, the carbon granules can be enmeshed into a foam system. A paradigm shift in carbon filtration is that fine activated carbon powder (-625 mesh) can now be used in a non-woven filter media when it is held within the structure by electroadhesive forces, without using adhesives or starches that would blind or possibly deactivate the carbon. Compared to media containing GAC, high-efficiency (powdered) activated carbon (PAC) offers a much greater external surface area, resulting in much more rapid adsorption of soluble contaminants (see Figure 1).