Study On The Optimization Of Film Forming Conditions And Storage Conditions Of Iron Manganese Composite Oxide Filter Media

With the development of our country's economy and society,the acceleration of industrialization and urbanization,the nonstandard behavior in the development and utilization of groundwater resources leads to the more serious pollution of groundwater by ammonia nitrogen and manganese.In order to meet and ensure the water safety of the country and residents,it is necessary to develop a process that can effectively remove ammonia nitrogen and manganese from the water.After years of exploration and research,the research team found that the iron manganese catalytic oxidation filter has the ability of simultaneous removal of ammonia nitrogen and manganese in water,and has the characteristics of high efficiency,economy and strong adaptability.Based on the research results of the research group for many years,this paper will further study the catalytic oxidation filter through the optimization of Fe/Mn ratio in the preparation stage of active iron manganese composite oxide filter material,the optimization of storage conditions of mature iron manganese composite oxide filter material and the pilot test of iron manganese composite oxide filter material to deal with sudden ammonia nitrogen/manganese pollution.The main conclusions are as follows:?1?It was found that the removal efficiency of the filter column with FeCl₂ in the initial stage of membrane formation was better than that without FeCl₂,and the removal efficiency of ammonia nitrogen was the best when Fe/Mn ratio was 1:1.As the ammonia nitrogen in the three filter columns can be removed at the stage of adding potassium permanganate,it shows that the three groups of iron manganese ratio membrane in the experiment have little influence on the removal capacity of ammonia nitrogen.With the increase of operation time of the system,the filter material is more mature,and the removal efficiency of ammonia nitrogen by the filter columns with different Fe/Mn ratios is similar.After stopping adding potassium permanganate,the oxidation film formed by the filter column with the ratio of Fe/Mn in the influent of 1:1 has the best removal effect on manganese,and the filter column with the ratio of Fe/Mn in the influent of 1.65:0.5has the worst removal effect.This shows that the capacity of manganese removal by the filter column is affected by the amount of manganese oxide generated.The more manganese oxide is,the better the effect of manganese removal by the filter column is.Therefore,the time of adding potassium permanganate can be prolonged properly when the membrane is hung,and more iron manganese composite oxides can be rapidly generated by using the strong oxidizability of potassium permanganate,so as to shorten the mature time of catalytic oxidation filter.?2?It is found that the storage time has a greater impact on the removal of ammonia nitrogen,a smaller impact on the removal of manganese,and the wet storage has a smaller impact on the removal of pollutants than the dry storage.After 10 days storage,the removal rate of ammonia nitrogen in the initial stage of filter column startup is more than70%.After 100 days storage,the removal rate of ammonia nitrogen in filter column is reduced to less than 35.57%,and the removal rate of ammonia nitrogen in dry storage filter material is even reduced to 12.73%.When the storage time is less than 40 days,the removal capacity of manganese in filter material is basically the same as the initial removal capacity of manganese in filter material.When the storage time is extended to70 days,the removal rate of manganese in dry/wet storage filter material is reduced to60.36%and 80.08%respectively when it is started;when it is stored for 100 days,the removal rate of manganese in dry/wet storage filter material is further reduced to 54.74%and 69.90%when it is started.The removal efficiency of ammonia nitrogen/manganese in each filter section of wet storage filter material is better than that of dry storage filter material,and the period of recovery to initial ammonia nitrogen/manganese removal capacity of dry storage filter material is longer than that of wet storage filter material.?3?It is found that the Fe-Mn composite oxide filter material has a good ability to deal with the sudden ammonia nitrogen/manganese pollution of groundwater.When the filter material is used to treat the ammonia bearing groundwater with a concentration of1.5 mg/L,the effluent of the filter column can reach the standard after running for 2-3days,and the ammonia nitrogen in the water can be completely removed in 4-6 days,with a load capacity of about 2 mg/L for ammonia nitrogen;when the manganese bearing groundwater with a concentration of 2 mg/L is treated,the manganese in the water can be completely removed in 2 days.The loading capacity of manganese is about 4.6 mg/L.