Study On Advanced Treatment Of Pharmaceutical Wastewater By Cobalt Doped Iron Carbon Microelectrolysis System And Its Coupling With CeCuO_x/PVDF Membrane MBR Process

In recent years,with the rapid development of the pharmaceutical industry,A large amount of untreated pharmaceutical wastewater is discharged into the water environment,resulting in water pollution that has seriously affected ecological balance and human health.Pharmaceutical wastewater has complex components,high concentrations of COD and ammonia nitrogen（NH₄⁺-N）,and contains a large amount of toxic,harmful,and difficult to degrade substances.At present,the conventional physicochemical pretreatment and biological Secondary treatment of pharmaceutical wastewater can not effectively meet the discharge standards,and its advanced treatment technology needs to be studied.In this paper,the prepared cobalt doped iron carbon micro electrolysis materials Fe-Co-AC（FCA）and CeCuO_x/PVDF composite membrane（CP）were used for the treatment of N,N-dimethylformamide（DMF）in the Secondary treatment effluent of pharmaceutical wastewater and the optimization of membrane bioreactor（MBR）.Finally,the advantages and disadvantages of the two processes were combined to establish a combined process of micro electrolysis enhanced ozonation MBR to explore the advanced treatment performance and stability of the combined process for pharmaceutical wastewater.The main conclusions are as follows:（1）A new type of FCA with regular appearance and good practicality was prepared using reduced iron powder,activated carbon,and cobalt nitrate as raw materials through a simple pressing and calcination method.This material has excellent removal performance for DMF in an ozone environment.Micro electrolysis and ozone oxidation form a synergistic effect to obtain hydroxyl radical（·OH）with high yield.When the ozone dosage is 6.10 mg/min,the FCA dosage is 60 g/L,and the hydraulic retention time is 60 minutes,the effluent concentrations of COD,NH₄⁺-N,and DMF in the wastewater are 69.6,35.5,and 0 mg/L,respectively,and the removal efficiency is 52.6%,7.3%,and 100%,respectively.（2）A 2D parallelogram flake like CeCuO_x nanosheet with regular structure was prepared using CeCuMOF as the precursor.CeCuO_x nanosheets were functionalized with PAA and grafted onto the surface of PVDF membrane to prepare CP composite membrane;The multiple advantages of membrane filtration and photocatalytic self-cleaning greatly reduce membrane fouling.And the composite membrane was used for MBR,and the modified membrane produced better water than the original membrane.The transmembrane pressure difference（TMP）increased slowly,and the anti pollution performance was improved.（3）The FCA and CP composite membranes prepared previously were used to form a micro electrolysis enhanced ozone oxidation MBR combination process and investigate its performance in deep treatment of pharmaceutical wastewater.Under the optimal conditions,the average values of COD,NH₄⁺-N,nitrate nitrogen（NO₃^--N）,turbidity,BOD₅,total nitrogen（TN）,and UV254 in the wastewater were 44.3 mg/L,4.6 mg/L,0.9 mg/L,0.4NTU,6.5 mg/L,14.1 mg/L,and 0.3 cm^-1,respectively.No nitrite nitrogen（NO₂^--N）and DMF were detected,and the effluent water quality met the Class A discharge standard of the Urban Wastewater Treatment Plant Pollutant Discharge Standard（GB 18918-2002）.The continuous operation experiment shows that the combined process has good stability and stable effluent quality,which has practical engineering application value.Figure:40 Table:11 Reference:137...