Chemical Engineering Research & Design, Vol.79, No.5, 569-574, 2001
A novel and low cost probe for monitoring dispersed solids concentrations in liquids
A conductivity probe has been developed for measuring the volume concentration of dispersed solids in a liquid. The design, with two pairs of electrodes, allows the probe to compensate automatically for any change in conductivity of the liquid phase. Initial test results with aqueous dispersions of talc are presented. The delay in the probe's response to changes in liquid conductivity is identified as the main limitation. Experiments to determine how rapidly a probe of 8 mm diameter responded to a step change in liquid conductivity at surface shear rates up to 1000 s(-1) are reported. A finite difference approach to modelling the response time is described. Finally, the effectiveness and applications of the probe are discussed.