| Pharmaceutical wastewater is one of the high concentration organic wastewater which is difficult to degrade because of its complex composition,large fluctuation,high COD value,many toxic substances and poor biodegradability.However,after secondary biochemical treatment,it still fails to meet the new standard issued by our country.By comparing the advanced treatment technology studied widely at home and abroad,a set of advanced treatment technology of pharmaceutical wastewater is designed,which is based on ozone catalytic oxidation technology,and applied to the advanced treatment of secondary biochemical effluent of pharmaceutical wastewater.Supported Ni and Cu as active components,the catalyst was prepared by impregnation-precipitation method usingγ-Al2O3 as carrier and urea as precipitant.The secondary biochemical effluent of pharmaceutical wastewater was used as the research object,and the effects of impregnation solution,metal ion concentration ratio,concentration ratio of urea and impregnation solution,calcination time and calcination temperature on the catalytic activity were investigated.The structure of the catalyst was analyzed by means of SEM and XRD and the stability of the catalyst was also studied.The experimental results showed that the activity of the catalyst was better when the the impregnation solution was 0.5 mol/L,the concentration ratio of urea and impregnation solution was 4:1,the Metal ion concentration ratio was 4:1,the calcination temperature was 50℃,the calcination time was 6h.The active components were mainly in the form of NiO and CuO.When the reaction was 90min,the removal rate of COD in the pharmaceutical wastewater was 67.57%.After the catalyst was reused for 10 times,the removal rate of COD and UV254 remained at about 60%,and it has good stability.In this paper,a fixed-bed reactor was used for ozonation experiment,and the relevant parameters of the experimental equipment and different influencing factors were investigated for the treatment efficiency of ozonation system.The experimental results showed that the power of ozonator was 30%,and the concentration of gas-liquid phase ozone reaches the maximum;the weak alkaline wastewater has better removal effect than the acidic wastewater;the low concentration wastewater has better removal effect than the high concentration wastewater.After a few minutes,the chromaticity of the wastewater fades rapidly,which considered that ozone has high selectivity for chromophores.The two grade effluent of pharmaceutical wastewater was treated by catalytic ozonation in the form of continuous flow and the effects of catalyst dosage,O3 dosage,hydraulic retention time（HRT）and initial pH value on the treatment effect were investigated.The results showed that the optimum operating conditions were as follows:the O3dosage was 30%*45L/h,the dosage of catalyst was 4g/L,the HRT was 30 min,and the initial pH value was 12-12.5.Under these conditions,after 200 min of the continuous reaction,the effluent quality basically reached a stable state,the removal rate of COD was about 60%,the pH value of the effluent was about 8.1-8.5,which met the discharge and reuse standards.On the basis of small-scale experiments,the process of ozone catalytic oxidation combined with MBR was developed to explore the removal effect of the combined process the feasibility of the whole process.The results showed that when MLSS was10.00g/L,HRT was 2.5d and COD load was 1.2kg/（m3·d）,the removal rates of COD and ammonia nitrogen were 60.14%and 80.36%respectively,and the ammonia nitrogen value was lower than 35mg/L,which reached the emission standard of the water pollutant discharge standard and had a good development prospect. |
