好氧生物反应器加速渗滤液及垃圾稳定进程研究

Effects of Aerobic Bioreactor Landfill Technology on Leachate Treatment and MSW Stabilization

针对垃圾厌氧生物反应器填埋中存在的酸化阶段过长、渗滤液氨氮积累等问题,采用实验室模拟填埋柱研究了上层曝气式生活垃圾好氧生物反应器在加速渗滤液污染物降解和加速垃圾稳定方面的效果。试验共设置4根填埋柱,其中厌氧生物反应器(C1)为对照,上层曝气式好氧生物反应器(C2、C3、C4)为实验组。各反应器每天回灌渗滤液,C2、C3、C4曝气时间分别设为2、4和8 h/d。结果表明,上层曝气式生物反应器能显著缩短酸化阶段所需时间,加速渗滤液有机污染物的降解。至实验结束时,各好氧生物反应器COD、BOD5均比实验开始时降低90%以上。此外,延长曝气时间,能够显著加速渗滤液含氮物质的的降解,至实验结束时,C3、C4渗滤液氨氮浓度分别降至99、39 mg/L,远低于同时期的C1和C2反应器。实验结束时,C1、C2、C3、C4垃圾沉降比分别为7.1%、8.6%、17.1%和21.4%,表明延长曝气时间有助于加速垃圾沉降,提高填埋场有效库容。

Anaerobic bioreactor landfill technology would result in long time of acidogenesis phase and accumulation of am- monia nitrogen in leachate. To solve the problems, 4 simulated bioreactors were built up, including an anaerobic bioreactor （C1） and 3 aerobic bioreactors （C2, C3, C4） with aeration on the upper layer. All the bioreactors were recirculated with leachate every day, and aeration intensity for C2, C3 and C4 were 2 h/d, 4h/d and 8h/d respectively. Results showed that or- ganic matters in leachate from all aerobic bioreactors decreased quickly over time. At the end of experiment, COD and BOD3 in leachate from C2, C3, C4 were all reduced above 90%. Increasing aeration time could accelerate the degradation of nitro- gen compounds significantly. In the end, concentrations of NH3-N in leachate from C3 and C4 decreased to 99 mg/L and 39 mg/L respectively. Waste settlements of 7.1%, 8.6%, 17.1% and 21.4% were observed in C1, C2, C3, C4, indicating faster sta- bilization and more space saved under longer aeration time.