厌氧-准好氧联合型生物反应器填埋场渗滤液水质水量变化规律的研究

为了减少生物反应器填埋场投资和运行费用,实现填埋场的快速稳定化,将厌氧型生物反应器填埋场(ANBL)和准好氧矿化垃圾生物反应床(SAARB)串联,组成新型的厌氧-准好氧联合型生物反应器填埋场(AN-SABL).通过研究AN-SABL渗滤液水质水量变化规律,以期为其渗滤液的管理和处理提供理论依据.实验表明,AN-SABL具有较好的渗滤液削减作用,最高削减量可达到771 g·kg-1;而且AN-SABL渗滤液水质变化具有明显的阶段性特征,渗滤液中硝酸盐(包括亚硝酸盐)浓度和氨氮浓度分别受Eh值和pH值影响明显.AN-SABL能够有效去除渗滤液中的有机物,实验结束时,AN-SABL2号和AN-SABL3号渗滤液COD的去除率分别达到了98.49%和97.98%,二者的COD浓度仅为ANBL1号COD浓度的14.5%、21.1%;同时,AN-SABL有较好的脱氮作用,AN-SABL2号和AN-SABL3号渗滤液中氨氮浓度分别从最高值1 452 mg·L-1、1 409 mg·L-1下降至525 mg·L-1、459 mg·L-1,只有ANBL1号氨氮浓度的36.5%和31.9%.SAARB单元的脱氮除碳效果受TOC/TC值的影响明显,当渗滤液中TOC/TC下降到0.2左右后,SAARB单元对COD和TN的去除率分别从95%和93%以上降到了35.25%～69.56%和64.53%～77.45%之间.

Evolution of Leachate Quantity and Quality in the Anaerobic-semiaerobic Bioreactor Landfill

The Anaerobic-semiaerobic Bioreactor Landfill (AN-SABL) has been devised combining an Anaerobic Bioreactor Landfill (ANBL) with a Semi-aerobic Aged Refuse Biofilter (SAARB) for reducing the investment and the running expense. It was a novel bioreactor landfill which could accelerate the stabilization of waste obviously. The evolution of leachate quantity and quality for the AN-SABL was studied in order to provide a theoretical basis for the management and treatment of leachate. The results indicated that the quantitative reduction of leachate in the AN-SABL was obvious and the highest reduction could reach by 771 g·kg^-1. Moreover, the quality of leachate varied in phases. The concentration of nitrate including nitrite and ammonium was influenced markedly by Eh and pH. At the end of the experiment, the removal rates of COD for the AN-SABL2 and the AN-SABL3 reached by 98.49% and 97.98% and the concentrations of COD were only 14.5% and 21.1% of that in leachate from the ANBL1 respectively. Therefore, the organic matter could be degraded completely with the AN-SABL. Besides, the AN-SABL could remove the nitrogen pollutant effectively as well. The concentrations of ammonium in leachate from the AN-SABL2 and the AN-SABL3 decreased obviously from the maximum of 1452 mg·L^-1 and 1409 mg·L^-1 to 525 mg·L^-1 and 459 mg·L^-1 respectively which only were 36.5% and 31.9% of that in leachate from the ANBL1. For the SAARB unit, the TOC and TC ratio played a vital influence on the removal efficiency of the organic matter and nitrogen pollutant. After the TOC and TC ratio declined to about 0.2, the removal rate of COD and TN for SAARB decreased from over 95% and over 93% to 35.25%-69.56% and 64.53%-77.45% respectively.