Dairy wastewater treatment using a novel low cost tubular ceramic membrane and membrane fouling mechanism using pore blocking models

This study investigated the potential application of a novel low cost tubular ceramic membrane in treating wastewater generated by a local dairy industry. The low cost tubular membrane ($0.5) with 0.309 mu m pore size, 53% porosity and 5.93 x 10(-7) m(3)/m(2)s kPa water permeability was fabricated from natural clay materials by extrusion technique. The capability of the membrane for treating real dairy industry wastewater was tested in tangential mode of microfiltration operation at different applied pressure (207-414kPa) and cross flow rate (5.55 x 10(-7)-2.22 x 10(-6) m(3)/s). An increase in applied pressure and cross flow rate on the microfiltration process resulted in a decrease in percentage removal of chemical oxygen demand (COD). The novel membrane achieved a maximum reduction in COD up to 91% (135 mg/L) in the permeate stream with a flux of 2.59 x 10(-6) m(3)/m(2)s, which is well within the permissible limit for wastewater discharge into the environment. These investigations affirmed the potential suitability of the membrane in dairy wastewater treatment to attain acceptable limit (< 200mg/L) of the permeate stream. Consequently, the membrane fouling mechanism was examined using conventional pore blocking models, viz. complete, standard, intermediate pore blocking and cake filtration model. The experimental results were well described by the cake filtration model. Additionally, the potential of the novel membrane was compared with other membranes reported in the literature for dairy wastewater treatment application. (C) 2016 Elsevier Ltd. All rights reserved.