Study On Ceramic Membrane Filtration And Its Combination With Oxidation For Treatment Of Micro-polluted Water

Ceramic membrane filtration and its combination with oxidation were used to treat micro-polluted raw water in the thesis. Raw water were taken from lake in University Town of shenzhen and Dongjiang River. The effects of operation conditions and different kinds of Pre-oxidations including dosage were tested. Head space- solid phase micro-extraction (HS-SPME) with GC-MS method was used to investigate the distribution of Dimethyl Sulfide (DMS) in the lakes, rivers, inlet and outlet of water plant.The results showed that ceramic membrane can effectively remove the turbidity from water, the turbidity in effluent are all under 0.1NTU, UV254, TOC, and CODMn can be removed by 20%~50%. The factors as membrane pressure, cross-flow rate and temperature can cause membrane flux changes. Optimal parameters for the ceramic membrane filtration were 0.15Mpa membrane pressure and 3m3/h cross-flow flux. During the raining season, Dongjiang river was polluted, the investigation showed that turbidity, UV254 and TOC all raise 4.6 times, 2 times and 2.5 ~ 3.75 times higher compared to dry season respectively. Concentrations of odor compound increased. The combination of ceramic membrane with oxidation showed the oxidation can significantly reduce membrane fouling. Ozone was a better choice among O3, H2O2, NaClO, and O3/H2O2. An appropriate dosage is 1.5mg/L for ozone. Pre-ozone can remove 20% to 35% of UV254 and 15% to 35% of TOC.Ceramic membrane has a low removal rate of odor compound, while its combination with oxidation can remove odor compound effectively. The DMS concentration can be decreased from 310 ~ 345ng/L to 7 ~ 64ng/L. Aeration of pure oxygen in 20 minutes can remove 5% of DMS, while aeration with 2mg/L of ozone, can remove 50%. The removal efficiency can reach to 71% when ozone concentration raise to 4mg/L.Ceramic membrane filtration and its combination with oxidation could effectively treat micro-polluted water can also reduce membrane fouling. It was of practical significance to the improvement of water plant.