回灌频率对联合型生物反应器填埋场的影响研究

为解决厌氧型生物反应器填埋场中氨氮积累问题,加速填埋场的稳定化进程,将厌氧生物反应器填埋场和准好氧矿化垃圾反应床串联。实验设置了1个厌氧型生物反应器填埋场(ANBL1#)作为参照组,2个厌氧-准好氧联合型生物反应器填埋场(AN-SABL2#、AN-SABL 3#)作为对照组,以研究不同回灌频率下AN-SABL的稳定化规律。研究结果表明:AN-SABL2#、AN-SABL3#可缩短酸化时间,渗滤液的pH值分别在94周、98周升至大于7,而ANBL1#渗滤液的pH值直至100周仍小于7。AN-SABL系统可有效降解渗滤液COD浓度,实验进行到100周左右时,AN-SABL2#、AN-SABL3#系统中厌氧柱D2、D3柱COD浓度仅为ANBL1#系统中厌氧柱D1柱的40.63%、12.5%,而准好氧柱对渗滤液COD的去除率大部分在95%以上。AN-SABL系统能缓解厌氧型生物反应器填埋场中氨氮积累问题,这主要依靠矿化垃圾床良好的生物脱氮作用,厌氧柱D1、D2、D3中NH3-N含量总体趋势为:NH3-ND1>NH3-ND3,NH3-ND1>NH3-ND2,准好氧d2、d3柱氨氮去除率均在90%以上,且厌氧-准好氧联合型生物反应器填埋场(AN-SABL)在实验产酸阶段低回灌频率(3 d/次)对氨氮的去除有利,而后期高回灌频率(1 d/次)更有利。

Effect of Recirculation Frequency in Anaerobic-semiaerobic Bioreactor Landfill

Anaerobic bioreactor landfill with a semi-aerobic aged refuse bioreactor was studied for reducing high concentration ammonia nitrogen cumulated in anaerobic bioreactor landfill,in order to accelerate the stabilization of landfill.ANBL1#,a simulated anaerobic bioreactor,as the reference group and two simulated anaerobic-semiaerobic bioreactors(AN-SABL2#,AN-SABL3#)as control groups were devised,for studying the stabilization of AN-SABL operated at different leachate recirculation frequencies.Results indicated that leachate pH value in ANBL1# remained less than 7 until the 100th week.By contrast,the pH value of leachate in AN-SABL2# and AN-SABL3# both rose to more than 7 after 94 weeks and 98 weeks respectively,which demonstrated that AN-SABL could make acidification phase shorter.COD concentration of leachate was reduced in AN-SABL more effectively.COD concentration in the simulated anaerobic bioreactor(D2)of AN-SABL2# was 40.63% of that in the simulated anaerobic bioreactor(D1)of ANBL1#,and that in the simulated anaerobic bioreactor(D3)of ANSABL3# was only 12.5%.The removal rates of COD in the simulated anaerobic-semiaerobic bioreactors were mostly more than 95%.AN-SABL can reduce high concentration ammonia nitrogen accumulated in anaerobic bioreactors,which depends on strong nitrogen removal ability of semi-aerobic aged refuse bioreactor.The overall trend of NH3-N concentration in the simulated anaerobic bioreactors is as NH3-ND1> NH3-ND3,NH3-ND1> NH3-ND2.The removal rates of ammonia nitrogen in simulated anaerobic-semiaerobic bioreactors(d2,d3)were almost more than 90%.In the acidification phase,the lower leachate recirculation frequency(once 3 d) was better for ammonia nitrogen removal,in contrast that higher leachate recirculation frequency(once a day)was more favorable in the anaphase.