Measuring and modelling flux recovery during the chemical cleaning of MF membranes for the processing of whey protein concentrate Original Research Article

The microfiltration of milk based products is used industrially as a partial sterilisation technique and to facilitate selective separation of components. This paper describes (i) an experimental apparatus, protocol and key results and (ii) the development of a mathematical model, describing the flux recovery occurring when a 2.0 μm sintered stainless steel flat-sheet membrane fouled with reconstituted whey protein concentrate (WPC) powder is cleaned using aqueous sodium hydroxide. The model describes the unsteady-state hydraulic resistance variation which occurs when surface and in-pore bound material undergoes morphological changes during caustic cleaning. The model relies on simultaneous removal and swelling processes occurring within the surface and in-pore deposits, respectively. The validity and applicability of the model is discussed, along with possible future modelling developments.