Contaminated oily wastewater treatment using composite membrane adsorption reactor

Increased harmful pollutants emission into the environment poses a serious threat to the ecosystem and human health and mitigation of such problem has become a worldwide focus. In this research, the treatment of contaminated oily wastewater is investigated using a composite adsorptive membrane made of double-layer activated carbon-polymeric membranes shielded by a superhydrophilic (SHPI) porous material. The latter was prepared by immobilizing ZnO nanoparticles on stainless steel mesh using the spraying method. Using methylene blue dye and hexadecane as model contaminants, the composite membrane showed efficient pollutant adsorption as well as an almost total oil repellence by the SHPI material. Both experimental and theoretical studies of the adsorption characteristics were also conducted in a pilot-scale hybrid adsorptive membrane reactor using the prepared material. Estimation of the energy consumption in terms of electrical energy per order (E_EO) was investigated and found much lower than that of nanofiltration (NF) for the treatment of dye-contaminated effluents. An order of magnitude estimation of treatment unit cost using the proposed approach was found to compare favorably with reported conventional wastewater treatment costs.