Study On The Changes Of Inorganic Ions By Leachate Recirculation Process

At present,almost 90% of the municipal refuse in our country was treated with the technology of landfill. Leachate is kind of high concentrated organic wastewater yielding from the processes of MSW (municipal solid waste) landfill or packing. Since the fluctuation of quality andquantity,and full of harmful pollutants,leachates pose pollution to the environment. recirculation is a kind of processing technology to treatment the lenchates.This paper based on the previous studies,combined with the change of COD and NH3-N,emphasis on the inorganic ions(Cl- SO42-),to do further measurement and reseach.lt can improve the theoretical system of recirculation,and provide the basic parameters to applicate the technology of leachate recirculation.The experimental study found the following conclusions:â… .The SO42- of leachate determined by Barium chromate spectrophotometry, Comparison of weight and capacity titration method,it has advantages of high determined speed and more accurate data.â…¡.As a nutrients of microbial growth, SO42- provide the inorganic sulfur source.Don't recirculation 2 device,the SO42- content between 330-430mg/L,and don't presented obvious accumulating. Aerobic and oxygen 5 device compared with anaerobic and oxygen 3,4 devices, SO42- Content low is more obvious.â…¢. The experimental process, not recirculation processing 2 device leachate Cl- a cumulative trend, to end of experiment in 6800mg/L or so stable; Recirculation processing 3, 4,5, device, recirculation early chlorine ion in the lower obviously, when growth and reduce after enter laboratory after the second stage, the basic smooth, slightly accumulating. Better oxygen and oxygen and anaerobic and oxygen recirculationg processing, inorganic chloride ions change did not reflect differences.â…£. Combined with the experimental process of chloride ion and COD inorganic monitoring data can be analyzed, proper leachate at a high content of Cl- measured, one COD value also greatly. Reduce leachate, the inorganic Cl- content, after a month of injection, content is still present accumulation trends; Meanwhile, the leachate recirculation processing COD better effect, but when Cl- content accumulated to a certain content (3000mg/L) after, the COD content will appear to rise.â…¤. Cl" determination of COD the existence of some errors, and along with the Cl" increases the error also generated increasing concentration, when Cl" produced when 3550mg/L,error less than 4 percent, in the acceptable limits. Masking agent to join will reduce potessium dichromate determination of the COD potassium backflow of error, best masking agent with the addition of the concentration of ratio for Cl- 10:1.