Study On Treatment Of PAM Wastewater By Electrochemical Oxidation

Polyacrylamide produces a large amount of wastewater containing polyacrylamide in production,crude oil exploitation,water treatment,textile,papermaking and other applications.The wastewater is difficult to biodegrade,difficult to treat,and the accuracy of the determination method is not enough.Therefore,firstly,the determination method of Polyacrylamide in wastewater is optimized to provide accurate experimental data for subsequent experiments;Then the electrocatalytic oxidation method is used to conduct in-depth experimental research on the treatment of polyacrylamide self prepared and actual wastewater,in order to find a new economic and effective way for the treatment of wastewater containing polyacrylamide.The main research results are as follows:（1）The experimental results show that the optimal wavelength for the determination of polyacrylamide concentration by starch cadmium iodide method is590 nm,the optimal p H of buffer solution is 5.0,the amount of saturated bromine water is 1.0 ml,the optimal reaction time is 10 min,the reaction time of sodium formate is 5 min,the color reaction time is 15 min,and the amount of starch is 5 g/L.the addition of electrolyte has no effect on the determination results.The fitting linear regression equation is y=340.81x+1.4021,and the correlation index R²=0.9991.This method can more accurately determine the concentration of polyacrylamide.（2）The effects of several influencing factors of electrocatalytic oxidation on the removal rate of polyacrylamide and TOC in self prepared wastewater were investigated,so as to verify the feasibility of electrocatalytic oxidation in the treatment of polyacrylamide wastewater.The experimental results show that when the anode material is titanium Plated Platinum plate and the cathode material is titanium plate,the initial p H is 9.0,the electrolyte concentration is 6000 mg/L,the current density is 50 m A/cm²,the distance between plates is 1.5 cm,and the reaction time is controlled for 70 min,the removal rate of Polyacrylamide in the electrocatalytic oxidation reaction system is close to 100%,and the mineralization rate of TOC is 36.43%.（3）Taking the oilfield polyacrylamide wastewater as the research object,the optimal treatment conditions of self prepared wastewater are applied to the actual wastewater,the treatment effect is evaluated,the reaction mechanism and degradation path are explored,and the technical and economic analysis is carried out.The experimental results show that the removal rates of polyacrylamide,TOC and TN are99.99%,21.76%and 40.54%respectively.The removal effect of electrochemical system can meet the actual needs.Under the direct attack of strong oxide active chlorine and hydroxyl radical,the structure of polyacrylamide changed and broke into various small molecule organics,and some small molecule organics were further mineralized into CO₂ and H₂O.At the beginning of the reaction,the amide group is oxidized to free ammonia nitrogen,and the nitrate nitrogen is reduced to nitrogen to be removed.Through comparison,the technology has high economic benefits and application value.