Removal of coke particles from oil contaminated marun petrochemical wastewater using pvdf microfiltration membrane

In this paper, an experimental study of a polymeric PVDF microfiltration membrane is presented for complete removal of coke particles from the industrial wastewater of Marun Petrochemical Company. The operation parameters such as applied pressure, cross-flow velocity, and feed temperature were investigated. The effect of coke concentration in filtration of the synthetic feed showed that coke particles did not transport from the membrane in all concentrations and sequence filtrations. In addition, 100% rejection of coke particles was kept constant by changing the operation parameters or using different cleaning agents due to suitable selection of pore size and polymeric materials of the applied membrane. At higher applied pressures, the higher flux is obtained due to the higher driving force toward the membrane. Feed flux was enhanced by increasing the cross-flow velocity explained by raising mass transfer coefficient in the concentration boundary layer and producing more shear stress on the membrane surface. Three different types of cleaning agents (HCl, NaOH, and NaOCl) were used for feed flux recovery of the fouled membranes. Flux recovery results and surface SEM images of the cleaned membranes indicated that most of the foulants were successfully removed using NaClO as chemical cleaner. The sequence of cleaning agent effect on flux recovery was NaOCl > NaOH > HCl. Hypochlorite solution due to having oxidizing properties in addition to alkali properties resulted in a higher cleaning efficiency compared to NaOH.