Permeate recirculation impact on concentration polarization and fouling on RO purification of olive mill wastewater

摘要: Abstract Analysis of permeate recirculation impact on membrane concentration polarization and fouling was studied upon well-controlled reverse osmosis (RO) experiments for final purification secondary-treated olive mill wastewater (OMW). Two commercial RO membranes presenting different characteristics, that is, a thin-film composite (TFC) low-pressure one, were selected comparison purposes. Incrementing the ratio to feed tank (10–30%) reduced build-up, is 15.8–42.1% TFC whereas 22.9–55.2% membrane. This fact especially relevant which triggers rapidly causing severe flux loss, but tends stabilize 30% recirculation. Moreover, irreversible satisfactorily minimized, reducing scaling formation permitting restoration initial permeability. The index can be minimized by 57.1% recirculating stream (measured at 15 °C), also 47.1% reduction observed same ratio. data obtained in this study highlight as an important operating variable control OMW.