CLEANING OF ULTRAFILTRATION MEMBRANES AFTER TREATMENT OF OILY WASTE-WATER

The influences of different types of cleaning agents on a polysulphone ultrafiltration (UF) membrane which had been used to treat oily waste water were investigated. The cleaning experiments were performed with samples of polysulphone membranes removed from a commercial plant in which oily waste water is treated. Five different cleaning agents were used and their influences on the fluxes were investigated. The influe nce on the flux when cleaning with the different cleaning agents in su ccession was also studied. Deposits on the membrane surface, before an d after cleaning, were analysed using different methods. Most of the a nalyses were carried out using scanning electron microscopy (SEM) in c ombination with energy dispersive X-ray (EDX) combined with a micro-an alysis system permitting quantitative determination of elements. Some analyses were also performed using Fourier transform infrared spectros copy (FTIR) and X-ray photoelectron spectroscopy (XPS).