Reclaiming protein in dairy wastewater with ultrafiltration

The investigation of ultrafiltration for recycling the protein in dairy wastewater was performed.The effect of transmembrane pressure,feed flow rate,concentration ratio on the recovery efficiency and the COD removal efficiency of ultrafilation membrane were studied.The experimental results show that the optimum operation pressure is 1.0 MPa,the feed flow rate is 32 L/min.Under such optimum conditions,the recovery rate of protein is 97.18%,and the removal efficiency of COD is 86%.The permeate of ultrafilation membrane can be used as high quality feed of following nanofiltration to recover lactose.