| The technology of Reverse Osmosis （RO） has been widely applied in the refinerybecause of it’s advantage of convenience and efficiency. We can obtain about75%of freshwater and25%of RO concentrated water which can’t meet the nation emission standard byRO technology. RO concentrated water contains hard-biological （non-biological） degradablesubstances. A little antisludging agent and bactericide and RO concentrated water has thecharacters of high salinity, poor biodegradability, difficult handling and high costs. Therefor,refinery wastewater treatment device were almost not equipped with effective ROconcentrated water treatment facilities at home and abroad. And RO concentrated watertreatment is a hard problem which restricts the refinery to achieve zero discharge of sewage.Ozone has a strong oxidation ability. Advanced Oxidation of Ozone, such as O3/H2O2,UV/O3, US/O3, CAT/O3et al, can produce a stronger oxidizing hydroxyl radicals. Ozonedirect oxidation and ozone advanced oxidation technology is widely used in refractory,degradation of toxic substances research. The core of advanced oxidation technology is toproduce as much as possible·OH. The factors of·OH generated influence has beenwidespread concerned.Mass Transfer and Chemical Reaction carried out simultaneously when the ozonationhappens in the water. Ozone is solubility in the water. So, the mass transfer of ozone from thegas phase to the liquid phase is a major factor which affects the utilization of ozone.Micro-bubble aeration can strengthen the mass transfer of ozone, and increase the ozoneutilization. Therefore, this paper used micro-bubble aeration to strengthen ozone oxidationand treatment RO concentrated water. Then, the factors of·OH generated influence wereinvestigated in the system of ozonation. The results are as follows:（1） The quality of RO concentrated water of a refinery wastewater treatment plant wasanalyzed by GC-MS. The main organics in RO concentrated water were aromatic compounds,phenolic compounds, esters and a little cycloalkanes. （2）A set of experimental device which can generate microbubbles of ozone by EDURto treatment RO concentrated water was designed and installed. The operating conditions ofthe device were determined. And the device can run stably under the conditions of dissolvedair pump inlet vacuum0.025MPa, dissolved air pump outlet pressure0.18MPa, gas-liquidvolume ratio10%.（3）Treatment efficiency and influencing factors of RO concentrated water withO3/H2O2process were investigated, in which O3/H2O2process was enhanced by microbuble,and microbuble was produced by dissolved air pump. The effects of ozone dosage, the initialmole ratio of H2O2/O3, pH and reaction temperature on the degradation of RO concentratedwater were discussed. The degradation efficiency of COD approximately linearly increasedwith the increasing ozone dosage. Proper H2O2added could improve the degradationefficiency by ozonation. The degradation efficiency firstly increased then decreased when theinitial mole ratio of H2O2/O3was00.8, and the optimum initial mole ratio was0.5. Thedegradation efficiency firstly increased then decreased in the range of pH6.84-10.03, and theoptimum pH was9.01. Rising temperature the degradation efficiency increased observably atlow temperature, but the reaction temperature had no remarkable effect on the degradationefficiency at higher temperature in the temperature range of14oC to28oC.The range of effluent COD were39.949.9mg/L under the conditions of initial moleratio0.5, pH89, ozone dosage80-100mg/L, COD90140mg/L at1028oC after410h.Removing1g COD consumed1.43.3g ozone and2.24.4g total oxygen. Thebiodegradability of RO concentrated water was poor after O3/H2O2process.（4）The effect of pH on the degradation of RO concentrated water by ozonation werediscussed. The degradation efficiency firstly increased then decreased in the range of pH6.3011.01, and the optimum pH was8.55, the maximum degradation rate was43.7%.Treatment efficiency of RO concentrated water with O3/H2O2process was better than sigleozonation. After6h, the degradation efficiency of COD were58.4%and43.7%, respectively.（5）·OH was detected in the process of ozonation by HPLC method, in which SA wasselected as the catcher. The quantity of the ozonation products of SA were determined, and theimpact factors of generation of·OH were discussed. Experimental results showed that theamount of generated·OH in the process of ozonation firstly increased then decreased with the increasing of pH from2to10, and the amount of generated·OH was maximum at pH6. Theamount of generated·OH increased with the increasing of SA concentration, but the growthtrend becomed slower, and the amount of generated·OH was maximum at SA concentration6mmol/L. The amount of generated·OH firstly increased then decreased with the increasing ofoxidation reaction time. |
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