Preparation Of Corn Stover Activated Carbon And Its Application In Landfill Leachate Treatment

In this experiment,the activated carbon adsorbent was prepared by using corn stalk activated carbon as raw material,and its adsorption performance was determined by chemical and physical characterization,and the data were analyzed by isothermal adsorption curve and kinetic analysis.Then it was put into SBR to establish BAC packing device,and its nitrogen removal efficiency was compared with SBR device,and the best working mode of BAC reactor was studied.Nitrogen removal pathway of BAC device;The contribution of activated carbon to reducing membrane pollution was determined by observing the EPS changes of the two devices.Finally,the optimal environmental conditions for BAC device nitrogen removal were determined by analyzing the influence of different conditions on the nitrogen removal efficiency of BAC device.The main research contents and conclusions are as follows:The linear correlation coefficient R²=0.86 of Langmuir isothermal adsorption model was greater than that of Freundlich model（R²=0.998）.That is,the adsorption mechanism of self-made activated carbon is closest to Freundlich isothermal adsorption model,that is,the surface of self-made corn stalk activated carbon presents uneven distribution,and the adsorption potential at the point is also different.Through Lagergren quasi-primary and secondary kinetics,it is found that Lagergren quasi-secondary kinetics model can describe the kinetic process of ammonia nitrogen adsorption by corn stalk activated carbon most accurately,that is,the adsorption potential of activated carbon per unit area is determined,and this adsorption process is mainly chemical adsorption.The ratio of ammonia to nitrogen oxidation rate and nitrite to nitrogen oxidation rate in BAC reactor are both higher than those in SBR,but the NO₂-N generated in SBR unit is significantly higher than that in BAC unit,that is,a large amount of NO₂-N generated in BAC unit is removed through efficient denitrification reaction.That is,the denitrification and nitrogen removal performance of BAC device is obviously better than that of SBR device.At the same time,due to the addition of activated carbon,reactor B has A better removal effect on EPS in water compared with reactor A,which can inhibit the secretion of EPS and adsorb it,and effectively reduce the membrane pollution effect in actual water treatment.In BAC device,increasing the amount of activated carbon promoted the denitrification reaction but inhibited the nitrification process.The nitrogen removal efficiency of BAC reactor is greatly affected by the biodegradability of carbon source.Selecting sodium acetate as additional carbon source in BAC device can get the best nitrogen removal effect,and the average TN removal rate reaches 61.75%.Glucose had the lowest nitrogen removal effect,and the average TN removal rate was 50.7%.The best nitrogen removal effect can be obtained by selecting sodium acetate as additional carbon source.Temperature has great influence on the nitrogen removal effect of simultaneous nitrification and denitrification in BAC device,and too high or too low temperature is not conducive to simultaneous nitrification and denitrification in BAC device.In this experiment,the nitrogen removal efficiency of the device with the temperature of 30℃is higher than 15℃and 45℃,and the best simultaneous nitrification and denitrification effect is achieved.In conclusion,the self-made corn stalk activated carbon has a good adsorption and removal effect on nitrogen,and the BAC packed reactor has a higher removal efficiency than the SBR reactor.