An integration process of ceramic membrane microfiltration (MF) with powdered activated carbon (PAC) was used to treat the oil-in-water emulsion in order to enhance the treatment efficiency. The role of PAC addition in flux enhancement mechanisms was investigated in detail. Results showed that the membrane flux for this system with particles was obviously higher than that of the oil-in-water emulsion alone. Combined with FESEM and EDS analyses, it was concluded that the gel layer formed on the membrane surface could be obviously reduced due to the mechanical scouring effect of particles according to the estimation of hydrodynamic forces, resulting in a higher membrane flux. The addition of PAC had no obvious effect on the removal efficiency of TOC and p-xylene, and they were removed about 96% in all cases. In short, the results of the present study demonstrated that the use of PAC as an additive in the integrated MF-PAC system was effective to mitigate membrane fouling and as a result increased the membrane flux because of scouring action. (C) 2010 Elsevier B.V. All rights reserved.