Experimental Study On Treatment Of Chemical Wastewater By Anaerobic Technology Loading With Micro-electric Field

Anaerobic biological treatment technology is considered to be one of the most economical and effective methods for the treatment of refractory organic wastewater,being widely used among domestic and overseas.However,the traditional anaerobic treatment method is greatly affected by pH value,temperature and other environmental factors,which is difficult to adapt to the characteristics of chemical wastewater.There is a lower COD removal efficiency,and it is difficult to meet the discharge standard of wastewater.So how to improve the efficiency of biological treatment and improve the biotoxicity of refractory organic compounds is still the focus of many scholars.Therefore,the method that mixing zero-valent iron and carbon fusion of building space multiple micro electric field and the coupling of anaerobic microbial will be proposed,which can improve the activity of anaerobic microorganisms and its scope greatly,and strengthen the biodegradation of refractory organic compounds,and achieve the aim that treat refractory organic wastewater with a simple,direct,efficient and low consumption method,providing a new development method for the effective biological treatment of difficult degradable organic wastewater.In this study,batch experiment was used to study the effects of pH value,hydraulic residence time（HRT）,temperature,iron/carbon addition ratio and other factors on anaerobic biodegradation efficiency,and the optimal reaction conditions were determined.It was found that the optimal pH range of the system was between6.5 and 7.0,and the maximum removal rate was 84.18%.The removal rate of COD and NH₄⁺-N increased with the increase of HRT,and the biodegradability was significantly improved.The optimal HRT of the system was determined to be 48 h.When the ratio of iron to carbon was 1:1,COD,NH₄⁺-N and B/C all reached the maximum value.When the temperature was 25℃,the removal rate of COD and NH₄⁺-N was the maximum,and the biochemical treatment increased by 90.18%.According to the single-factor experimental analysis results,three factors including temperature,HRT and iron and carbon mass addition ratio were selected for the three-factor,three-level orthogonal test.Experiments showed that temperature and HRT had a greater impact on the removal efficiency of COD and NH₄⁺-N.This research is based on the treatment of mixed industrial wastewater in Daqing Xinghua Park Wastewater Treatment Plant,focusing on solving the problem of refractory degradation of industrial wastewater that is increasingly difficult to handle in domestic industrial wastewater treatment plants.The multi-micro-electric field and MBBR are loaded into anaerobic biological treatment process.In the process of loading A/O,BAC and MBBR into aerobic biological treatment process,the biodegradation of refractory organic matter is strengthened,and the purpose of treating refractory industrial wastewater is simple,direct,efficient and low-cost,and it is effective for industrial wastewater.Biological treatment opens up new avenues.Based on the investigation of the complex and difficult-to-degrade characteristics of water quality in Xinghua Park,the static experimental study of Fe⁰/Fe²⁺coupled anaerobic biological treatment and the static experimental study of multi-micro-electric field coupled anaerobic biological treatment were carried out,and the best solution was determined by comparison.Pilot scale trials provide theoretical support and data support.The research on the treatment of chemical wastewater by loading anaerobic/complex aerobic process was carried out.The effects of parameters such as hydraulic retention time,influent pH and temperature on the degradation efficiency of the process were investigated.The effluent reached the standard after stable operation.The main conclusions of this paper are as follows:（1）The efficiency of Fe⁰/Fe²⁺coupled anaerobic biological treatment is affected by temperature,HRT,Fe⁰/Fe²⁺dosage ratio and pH.The temperature,HRT and Fe²⁺/Fe⁰ mass dosing ratio were used to carry out the three-factor and three-level orthogonal tests to determine the maximum effect of COD and NH₄⁺-N removal efficiency.The influence law is temperature>HRT>Fe²⁺/Fe⁰ quality.Casting plus.（2）Fe⁰/Fe²⁺coupled anaerobic microorganisms can strengthen the treatment of refractory organic wastewater,improve the organic matter removal rate of wastewater biological treatment system and the biodegradability of wastewater.The optimal parameters for the experimental study of Fe⁰/Fe²⁺coupled anaerobic enhanced chemical wastewater treatment were as follows:HRT was 48h,Fe²⁺/Fe⁰ mass dosing ratio was 0.001:1,initial pH of mixture was 6.5,temperature was 25℃,and temperature The impact on removal efficiency is greatest.Through the study of multi-micro-electric field coupled anaerobic enhanced biological treatment technology,the following conclusions are drawn:（1）Experimental study on the biological treatment efficiency of anaerobic biological system at different initial pH conditions at 20℃,the ratio of iron to carbon is 1:1,the optimal pH of the system is 6.5⁷.0,and the removal rate reaches the peak.It is 84.18%.（2）Experimental study the effect of different HRT on anaerobic biodegradation efficiency at 20℃ with initial pH of 7.0 and iron-carbon addition ratio of 1:1.The results show that the removal rate increases with the increase of HRT.From the perspective of actual process cost savings,the optimal HRT is determined to be 48 h.（3）Experimental investigation At 20℃,initial pH value of 7.0,HRT was 48 h,the effect of different iron and carbon dosing ratio on the efficiency of anaerobic treatment of refractory organic wastewater was investigated.The experimental results show that when the mass ratio of iron to carbon is 1:1,COD,ammonia nitrogen and B/C reach the maximum value.（4）According to the results of single factor experiment analysis,the temperature,HRT and iron carbon mass dosing ratio were used to carry out the three-factor and three-level orthogonal test.Temperature and HRT had the greatest influence on COD and ammonia nitrogen removal efficiency.In the pilot test of chemical wastewater treatment by anaerobic/complex aerobic process,the biodegradability of sewage after anaerobic treatment is effectively improved.Under the optimal process parameters,the combined process was stable for one month.The average COD concentration in the influent was 1561.87 mg/L,HRT=50 h,the temperature in the anaerobic reactor was 17-18℃,and the aerobic reactor was in the range of 17.7¹8.3℃.The result shows that the average effluent COD concentration was 148.85 mg/L,COD effluent reached 101.60 mg/L,and the average COD removal rate reached 90.42%,reaching the second-level emission standard,providing reliable experimental data support for water plant upgrading and transformation and theoretical support for the stable operation of the combined process.