PARTICLE REMOVAL BY POWDER FILTERS

Specification of a grade of perlite or kieselguhr is best achieved usi ng mean hydraulic radius which is a value based on effective bed voida ge. A numerical prediction of clarification capability has been obtain ed from filtration trials even when the filter bed structure has been disrupted by beer solids. Rapid grading of perlites is possible from a ssessment of powder permeability. Removal of very small haze particles from beer by fine grades of powder was attempted but not achieved. Th is effect would be explained by the relatively high shear forces exper ienced by the beer particles on the pilot candle filter employed in th e trials, compared to full-size beer filters.