Research On Treatment Of Biochemical Tail Water Of Landfill Leachate By Coagulation-catalytic Oxidation Combined Process

Landfill leachate is a highly organic,highly toxic,and low biodegradable waste water produced during landfilling of municipal solid waste.At present,the treatment of leachate is mainly biochemical+membrane treatment.However,this method will produce the concentrate,more difficult to degrade,resulting in secondary pollution,so this experiment tried to apply coagulation+catalytic oxidation combination process to leachate biochemical tail water treatment to avoid the production of concentrated liquid.In this study,the coagulation-advanced oxidation combined process was used to treat the biochemical tail water of leachate,and a set of catalytic oxidation process pilot plant was designed in combination with the characteristics of catalytic oxidation technology.Its treatment effect on the continuous effluent of leachate was explored.The main research contents were as follows:The result is as follows:?1?PFC,PAC,and FC flocculants were used to pretreat the biochemical tail water of leachate,and COD and color removal were used as reference indicators.It was found that PFS was under the conditions of 800 mg/L and 1000 mg/L.The treatment effect of leachate was similar.Considering the cost factor,800 mg/L was chosen as the dosage of PFS.Based on this,the effect of adding pH and coagulant aid on the coagulation effect was studied and found that under the condition of pH=7,the combination of 800 mg/L PFS and 4 mg/L PAM has better treatment effect on leachate,the COD removal rate is 22.21%,the color removal rate is 57.85%,and the flocculation process can not adjust the pH.?2?A series of MgAl-LDH hydrotalcite materials containing transition metals such as Co,Fe and Cu were synthesized by co-precipitation method,and the optimal catalyst CoCu@MgAl was selected by treating the leachate coagulation effluent(Co²⁺:Cu²⁺:Mg²⁺:Al³⁺=0.15:1:15:5).On this basis,the impregnation method was used to load it on different carriers,and according to its treatment effect on leachate coagulation effluent,high-efficiency activated alumina was selected as the supporting material.?3?Using the supported catalyst to treat the leachate coagulation effluent static experiment to explore the optimal reaction conditions,the results found that:in the PMS dosage of 3 g/L,H₂O₂ dosage of 0.5 mol/L,Carrier catalyst dosage is 3 g/L,the reaction temperature was 40°C,and the reaction time was 2 h,the treatment effect was the best.The COD removal rate of coagulation effluent could reach 28.64%.?4?In order to realize the continuous effluent treatment of leachate,a set of laboratory test equipment was designed.According to the above studies,the reaction parameters were adjusted to the optimal reaction conditions.The results showed that the device had low treatment effect on the continuous effluent of leachate compare the static experiment,repeated tests on the supported catalyst revealed that the supported catalyst still has a certain treatment effect on the leachate after simple cleaning and drying.