Analysis and prediction of fouling layer structure in microfiltration

A dynamic analysis procedure has been adopted based on mass and force balances for particle deposition on the membrane surface to analysis and predict the particle fouling layer structure in microfiltration. The local properties in a fouling layer, say porosity distribution, resistance to fluid flow and hydraulic pressure distribution can be estimated by the proposed dynamic analysis with a preliminary request of a set of filtration data and the surface porosity of fouling layer only. A prototype software for the analysis of the fouling layer properties in microfiltration has been devised and can be used both for design of a membrane filtration system and later to predict or monitor its performance during plant operation.

In this study, a dynamic analysis procedure has been adopted based on mass and force balances for particle deposition on the membrane surface to analysis and predict the particle fouling layer structure in microfiltration. A prototype software FiltraDynaSim# V 1.0 for the analysis of the fouling layer properties in microfiltration has been devised and can provide the local properties in a fouling layer, say porosity distribution, resistance to fluid flow and hydraulic pressure distribution can be estimated by the proposed dynamic analysis with a preliminary request of a set of filtration data and the surface porosity of fouling layer only. Results depicted that the porosity of the fouling layer is one of the most import quantities for the estimation of the fouling resistance. From the porosity distribution in the fouling layer, it can be notice that the fouling layer is compressed during microfiltration and the local porosity in fouling layer decreases gradually. The decrease of porosity in fouling layer is mainly due to the rearrangement of particles and compression of fouling layer which are caused by the fractional drag from the fluid and the mass of foulant composited by depositing particles and hence causing a fast flux decline. From the comparison of the predicted results and the experimental data reveals that the adopted dynamic analysis procedures as well as the developed prototype software prove themselves to be useful tool not only for designing of a membrane filtration system but also for predicting or monitoring the system performance during plant operation.