A rotating disk ultrafiltration process for recycling alfalfa wastewater

Abstract

Abstract Rotating Disk Membrane (RDM) module with ultrafiltration (UF) was an effective alternative method to treat alfalfa wastewater and realize protein recovery and agricultural irrigation water production. The effects of membrane and operational conditions (rotating speed, temperature and transmembrane pressure (TMP)) on filtration behavior were investigated using full recycling tests. High molecular weight cut off (MWCO) membrane, rotating speed, temperature and TMP improved flux behavior and productivity, but reduced separation performance. Moreover, the increases of membrane MWCO, temperature and TMP also led to elevation of irreversible fouling. Then series of concentration tests were conducted at various operational conditions and the filtration behavior was studied. High temperature could improve flux behavior and productivity significantly. Hermia’s blocking model was used to study fouling process, and identify the main fouling mechanism. These results from laboratory-scale tests provide a useful guide for protein recovery and agricultural irrigation water production in alfalfa wastewater treatment and provide a useful guide for UF process operation in industrial scale.