Experimental Study On Treatment Of Pesticide Wastewater By Ultrasonic Wave And Iron Carbon Micro Electrolysis

Using large amounts of pesticides to in_crease food production is an important way to solve my country’s food problems,but the accompanying environmental problems affect nature and our lives.Water pollution is the focus of environmental pollution,and how to deal with pesticide wastewater has become a focus of attention.Through reading literature and collecting data,summarize and summarize the domestic and foreign water treatment technologies.Taking sewage from a pesticide factory as the research object,ultrasonic technology and iron-carbon micro-electrolysis technology are selected as treatment methods,and the influencing factors are explored to determine the best working conditions.In the experiment of only ultrasonic treatment of pesticide wastewater,16 sets of orthogonal experiments were performed on the initial pH value,ultrasonic time and ultrasonic power of the sewage based on the approximate range of the three influencing factors through exploratory experiments,and then 28 sets of single factor experiments were performed.The results of the difference analysis test show that the three factors are used to treat the COD_crinspection level P value of the sewage produced by the pesticide plant:P _{ultrasonic power}>P _{reaction time}>P _{initial pH value of the sewage}.The ultrasonic power has the greatest impact on the degradation of COD_cr.The actual best working conditions of ultrasonic treatment of pesticide sewage are:ultrasonic time 80min,ultrasonic power 4000W,and initial pH value of sewage 4.Under this working condition,the removal rate of COD_cr,TN and TP can reach43.54%,36.52%,55.31%.The degradation kinetics of COD_crconforms to the second-order kinetics.In the experiment of treating pesticide wastewater only by iron carbon micro electrolysis,16 sets of orthogonal tests were performed on the initial pH value,reaction time,and solid-liquid ratio of the wastewater based on the approximate range of the three influencing factors through exploratory experiments,and then 27 sets of single factor experiments were performed.The results of the analysis of variance test show that the three factors are used to treat the COD_crinspection level P value of the sewage produced by the pesticide plant:P reaction time>P solid-liquid ratio>P initial pH value of the sewage.The reaction time has the greatest impact on the degradation of COD_cr.The actual best working conditions of iron-carbon micro-electrolysis treatment of pesticide wastewater are:reaction time 150min,solid-liquid ratio 450g/L,and initial pH value of wastewater 3.5.Under this working condition,the removal rate of COD_cr,TN and TP can reach 37.89%,23.66%,42.13%.The degradation kinetics of COD_crconforms to the third-order kinetics.In the test of combined ultrasonic-iron-carbon micro-electrolysis treatment of pesticide wastewater,the combined process showed significant synergy,and the treatment effect was better than single-ultrasonic technology and single-iron-carbon micro-electrolysis technology in a shorter reaction time.The best working conditions of ultrasonic-iron-carbon micro-electrolysis combined treatment of pesticide wastewater are:ultrasonic power 4000W,initial pH value of wastewater 4,iron-carbon solid-liquid ratio 450g/L,and reaction time at70min.Under this condition,the removal rates of COD_cr,TN,and TP reached 57.96%,45.61%,and 69.88%,respectively.The degradation kinetics of COD_crconforms to first-order kinetics.The results show that the biodegradability of high concentration pesticide production wastewater is improved after the combined process treatment,which can be used to reduce the dilution ratio of pesticide production wastewater before biochemical treatment,and solve the shortcomings of low treatment efficiency and large water consumption of the current biochemical treatment technology of pesticide production wastewater.