Smiles' multiphase approach has been applied to the analysis of data arising from the microfiltration of montmorillonite particles which exhibit nematic ordering on accumulation on the membrane. Results obtained for different feed ionic strengths and applied pressures using Smiles' approach are consistent with results obtained using conventional cake filtration theory. Both approaches enable quantification of the effect of a step increase in ionic strength on increase in cake hydraulic conductivity. In addition, Smiles' approach provides a convenient means of describing the depth variation in solid volume fraction of the cake as well as local moisture content and pressure drop profiles. (C) 2008 Elsevier B.V. All rights reserved.