| The difficulty conditions in the treatment of high-ammonia and non-biodegradable organics landfill leachte, the paper takes The ChangSheng Bridge landfill leachte as the subject of investigation, and probe in the high efficient and low cost approach to treat this category of landfill leachate which have"Old age"characteristics. The SBBR reactor was adopted, and the nitrating effectiveness was also studied. The effects of water temperature, organic load, biofilm hang density and the alkalinity to nitrogen removal in SBBR was discussed. For the first time, the two-stage SBBR reactor system was presented, which can remove ammonia efficiently. Through domestication, build the high- ammonia endurance microorganisms, improve the N load rate significantly, and obtain the key processing parameters of it. On the other hand, in order to seek a highly efficient and low cost technology for the removal of non-biodegradable organisms, the paper studies on the effects of the coagulation, Fenton oxidation and microwave catalysis process and their combinations to the treatment of landfill leachate,Taking into account the influences on them by orthogonal experimental design, and obtain that the process of"coagulation+microwave oxidation"is the efficient way to lower the cost for the treatment of non-biodegradable organisms. Finally, the paper also focous on the improvement of biodegradability and the key parameter by ultrasonic wave. The reaction time, power and temperature on the influence on the treatment were also research. The main conclusions are as follows:①Under the temperature of 35℃,the Nitrogen loading rate was 0.15kgN/m3·d ,the biofilm hang density was 30% and hydraulic retention time(HRT) was 24h. The SBBR reactor can decrease NH4+-N from 1150~1250mg/L in influent to 12mg/L in effluent, meeting the primary standard of landfill leachate. The nitrating effectiveness shows improvement with rising temperature, the Nitrogen loading rate risen to 0.20kgN/ (m3?d), and the NH4+-N in effluent was less than 12mg/L in the temperature of 30℃. Compared with the one-state SBBR system, the two-stage SBBR system further improves the nitrating effectiveness significantly, its ability to double the treatment capability under the same nitrogen loading rate shows very promising progress..②In the Fenton oxidation process, under the condition of pH=3.0 ,[30%H2O2]=6.25ml/L,[Fe2+]=800mg/L,reaction time(t)=90min,the COD in effluent was decreased to 335mg/L,with 78.1 % removal rate, the color was 25,with 96.8% removal rate. In the microwave catalysis process, under the condition of pH=2.5,[30%H2O2]=4.20ml/L,[Fe2+]=533mg/L,reaction time(t)=5min and the 1.0g dosage of catalyst,the COD in effluent was 235mg/L,with 87.5% of removal rate. The result of orthogonal experimental design indicates that the degree of influence on Fenton oxidation were: H2O2>Fe2+ >pH >t; and the degree of influence on microwave catalysis were: Fenton reagent dosage> pH>catalysis dosage>t.③In the Fenton + coagulation process, under the condition of pH=3.0,[30%H2O2]=6.25ml/L,[Fe2+]=800mg/L,PAM=3mg/L ,reaction time=30min,the COD in effluent was 285mg/L,meets the secondary landfill leachate standard. In the coagulation—microwave process, under the condition of pH=3.0,PAC=1.5g/L,PAM=3mg/L,30%H2O2=2.08ml/L,Fe2+=0.26mg/L and the 1.0g dosage of catalyst, the COD of effluent was 265mg/L,which also meets the secondary landfill leachate standard. By applying the"coagulation—microwave"process, the dosage of reagent was decreased greatly, with 2/3 Fenton reagent and 1/2 PAC saved when compared to other similar processes.④Under the condition of input power=600w, frequency=28KHZ and reaction time=180min, by applying ultrasonic,it can improve the biodegradability from 65mg/L to 245mg/L, the ratio of BOD5/COD rises and shows progress from 0.038 to 0.140, clearly, the result indicate that the ultrasonic wave can improve the non-bioderadable landfill leachate effectively.
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