Application Of Membrane Separation And Advanced Oxidation Process In The Treatment Of Wastewater

Freshwater is vital to the sustainable development of economy and society.On the one hand,the increasing population has led to our persistent high demand for the water,on the other hand,the rapid economic development and accelerated industrialization have also caused serious trauma to the environment.If we apply with proper treatment technologies to reuse water,industrial wastewater may be turned into valuable resource and the crisis of water resources also can be released.The components of industrial wastewater are very complex and unstable.There are still so many technical problems that need to be solved.From this perspective,the development of low energy consumption and efficient refractory wastewater treatment technologies have become the focus and direction of treating industrial wastewater.The study applied ceramic membrane with reverse osmosis（RO）technology was conducted to assess the potential feasibility for reclaiming the effluent.In pretreatment process with tubular ceramic membrane,the experiment was carried in batch module for and the effect of different filtration stages and pressures on the wastewater treatment effect were investigated.It was concluded that the flux of ceramic membrane was about 150 L/（m²·h）and 190 L/（m²·h）at 0.1 MPa and 0.2 MPa respectively.One of the important purpose was to figure out the fouling mechanism of the ceramic membrane during filtration process by referencing the classic plugging model theory.Taking R² as the measurement standard,the cake flirtation fit best for the fouling module according to the liner fitting.Although the membrane undergoes some extent fouling,it can easily be cleaned through a chemical washing due to the fact that the permeability was approximately recovered by 96%after efficient cleaning.In the depth filtration technology,we used the commercial nanofiltration membrane and two different kinds of commercial reverse osmosis membranes to treat the waste collected from ultrafiltration（UF）process.It is suggested that nanofiltration（NF）membrane showed excellent selective desalting performance.The final water quality from RO membrane is suitable for recycling after being treated with COD below 50 mg/L and conductivity less than 230μS/cm for both TFC RO membranes.We used CuO/Al₂O₃ supported catalyst to study the degradation of polyvinylpyrrolidone（PVP）the in a heterogeneous semi-batch fluidized bed system.The experimental results showed that the TOC removal rate of artificial PVP wastewater was increased by 50.5%when the dosage of catalyst increased to 100 g,TOC removal rate was higher and PVP degradation effect gradually increased with higher solution pH value.The removal rate of TOC was higher than 28.29%after being reused 5 times.The addition of free radical inhibitor sodium bisulfite significantly inhibited the degradation of PVP,which proved that the oxidation system followed the mechanism of hydroxyl radical（·OH）reaction.