Ceramic hollow fiber membranes are investigated with respect to the fouling behavior. Constant pressure dead-end filtration experiments have been performed using alginate as model substance for extracellular polymeric substances. In addition to the evaluation of the filtration data using conventional cake filtration model, nuclear magnetic resonance imaging (MRI) was used to elucidate the influence of Ca 21 on the fouling layer structure for alginate filtration within ceramic hollow fiber membranes. To visualize the alginate layers inside the opaque ceramic hollow fiber membranes by means of MRI, specific contrast agents were applied. Supplementary to multi slice multi echo imaging, flow velocity measurements were performed to gain more insight into the hydrodynamics in the fouled membranes. MRI reveals the structure of the alginate layers with the finding that the addition of Ca 21 to the alginate feed solution promotes the formation of a dense alginate gel layer on the membrane's surface.

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A dead-end filtration process of skim milk with ceramic hollow fiber membranes was investigated using in situ Magnetic Resonance Imaging. Special emphasis was put on contrast optimization exploiting water relaxation times being sensitive to casein concentration in the formed deposit layer.

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