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In order to study the permeability characteristics of heavy metal ions contaminated red clay and explore the rapid detection of permeability of heavy metal contaminated red clay. Through variable-head permeability test and electrical resistivity test (different voltages and methods), the effects of Cu2+ concentration and initial water content on hydraulic conductivity characteristic and resistivity of contaminated red clay was systematically investigated. The relationship between permeability characteristic and electrical resistivity was further explored by taking Cu2+ concentration and moisture content as the intermediate variable. The obtained results indicate that the different voltage has no obvious effect on the resistivity of the samples. The four-phase electrode method is more accurate than the two-phase electrode method. With increasing Cu2+ concentrations the hydraulic conductivity of specimens increases, however the permeability coefficient of contaminated soil decreases with increasing initial water content. In the resistivity test, with increasing of Cu2+ concentrations and water content, the resistivity of samples presented a downward trend, which is decreased sharply at first and then tended to be gentle. The relationship between hydraulic conductivity and resistivity of contaminated soil showed a good fitting curve no matter in different Cu2+ concentration or in different water content, but the fitting curves of them presented opposite trend.

Experience from a new laboratory filter for measuring permeability and filtration rate of powdered filter aids is described. It is possible to measure flow rate across precoating layer of filter aid, even during coating. Beer filterability can be expressed by blocking value as well as so called filtration cake value by the Raible method. New rapid method uses precoating of the complex of beer, desposits and filtration material and subsequent measuring of filtration rate during water penetration through it. This new method makes possible to analyse effects acting to filterability of beer and effect of technologic precaution for improving of bad filterability.Experience from a new laboratory filter for measuring permeability and filtration rate of powdered filter aids is described. It is possible to measure flow rate across precoating layer of filter aid, even during coating. Beer filterability can be expressed by blocking value as well as so called filtration cake value by the Raible method. New rapid method uses precoating of the complex of beer, desposits and filtration material and subsequent measuring of filtration rate during water penetration through it. This new method makes possible to analyse effects acting to filterability of beer and effect of technologic precaution for improving of bad filterability.