Study On Ozone And RO For Reclaimed Water Treatment

At present, advanced treatment technology is widely used in the renewable watertreatment field. Reverse osmosis technology is used to achieve high desalination rateand ozone contact oxidation is used to remove the organic and color of renewablewater. In this paper, we utilize the middle-size equipment to conduct an experimentalresearch on the advanced treatment of submerged continuous micro filtration waterrealized by ozone contact oxidation and reverse osmosis treatment.（1）Determine the importance of impact factor in ozone treatment using middle-size equipment; exploring reasonable ozone process control parameters. Theinfluence factors are ozone concentration, retention time and aeration ration.（2）The influence of the duration hydraulic retention time on the effect of ozonecontact oxidation is studied. The result shows that, with the same ozone concentrationand aeration ratio, the retention time is longer, the processing result is better. If theretention time is more than25min, the removal rate slows down; with the same ozoneconcentration and hydraulic retention time, the aeration ratio is bigger, the processingresult is better.（3）The influence of inhibitor on reverse osmosis technology is studied. Thereare many factors influencing the effect of inhibitor. This article studies the influenceof the inhibitor consistency, water flow rate and system recovery of reverse osmosissystem; we also compare the inhibitor performance of two inhibitors(domestic andimported, both are mainly constituted by phosphorus-containing organic molecules).The results are1)The concentration of inhibitor is greater,the performance is better; ifthe concentration is more than2mg/L,the performance is smooth.2)If the flow rate islower than1000L/h, the performance of the inhibitor is better with the growth flowrate; if the flow rate is higher than1000L/h，the performance is worse with thegrowth of flow rate.3)The performance of the inhibitor decline with the rising ofrecovery rate.4）Performance of homemade inhibitor is better than imported inhibitorthrough comparison.（4）Study the pollution on diaphragm by single organic pollutants using small-size reverse osmosis experiment. In order to imitate the diaphragm pollution in actual operating conditions, the experiment is conducted on middle-size equipment. Use fourmethods as follows, scanning electron microscopy, energy dispersive analysis, Fouriertransform infrared spectroscopy scanning analysis, X-ray diffraction analysis toanalyze the membrane. The result shows that,in addition to organic dye material withchromophic conjugated groups,there is also inorganic dye material. Some specialmeasures should be taken in the coagulation and sedimentation unit in order toremove color of recycled water.（5）Based on existing equipments of the renewable water plant, according tothe current operating conditions, the best operating conditions can be determined.Firstly, establish mathematical model about ozone dosage; Secondly, establish theoptimized model of reverse osmosis treatment unit and ozone processing unitcoordinated operation. According to different operating conditions,there are differentbest operations. The expense of optimal operation conditions and actual operationconditions are compared. The result shows that, expense of optimal operation can besaved2.66%-8.73%, while the water production rate increases7.72%-16.79%, withsignificant economic benefit.