Analysis of membrane pore-blocking models applied to the MF of real oily wastewaters treatment using mullite and mullite-alumina ceramic membranes

In microfiltration (MF) membrane processes the typical variation of the flux with time is that of initial rapid decrease followed by a long and gradual decline. The results of an experimental study regarding analysis of membrane pore-blocking models in separation of oil from oily wastewaters outlet of desalting unit of Seraje, Ghom, Iran gas wells are presented. Mullite and Mullite-Alumina (25, 50 and 75% alumina content) membranes were synthesized from kaolin clay and -alumina powder as MF ceramic membranes. Hermia's model was used to investigate the fouling mechanisms of membranes at different time intervals (0-2.5, 0-5, 5-20, 20-120min), and (0-120min). It can be found that Hermia's model cannot be applied for prediction of permeation flux in any limited intervals of time since by increasing of time the filtration pore-blocking behavior changes and one model cannot predict pore-blocking behavior in all filtration time. In addition for (0-5min) interval, maximum error of predicted permeation flux of cake filtration model is 2.96% but for (0-120min) interval, minimum error of predicted permeation flux is 11.41%.