短程硝化-厌氧氨氧化组合工艺深度处理垃圾渗滤液

为解决垃圾渗滤液中高浓度污染物对微生物的毒性抑制、生物处理出水有机物或氮不达标及投加碳源成本高的问题,采用UASB(上流式厌氧污泥床)-A/O(缺氧/好氧)反应器-ANAMMOXR(厌氧氨氧化反应器)工艺,通过短程硝化-ANAMMOX(厌氧氨氧化)深度处理实际垃圾渗滤液与生活污水混和液(体积比为1∶10),其ρ(COD_Cr)、ρ(NH₄+-N)和ρ(TN)分别为(750±30)(290±10)和(300±10)mg/L,试验共进行90 d. 结果表明:COD_Cr、NH₄+-N和TN的去除率分别为88%±1%、95%±1%和91%±1%,最终出水质量浓度分别为(67±5)(15±2)和(35±5)mg/L,满足GB 16889—2008《生活垃圾填埋场污染控制标准》的排放要求. A/O反应器中的ρ(FA)(FA为游离氨)在0.21～1.38 mg/L之间,可抑制NOB(硝酸细菌),使AOB(氨氧化细菌)成为优势菌种,从而实现并维持NO₂--N积累率(70%～96%)较高的短程硝化,继而在ANAMMOXR中通过ANAMMOX去除残余NH₄+-N和NO₂--N,实现系统对氮的深度去除. 

Advanced Treatment of Landfill Leachate by Combined Process of Partial Nitrification and Anaerobic Ammonium Oxidation

In this study, an in-line system with a combined upflow anaerobic sludge bed (UASB)-anaerobic/aerobic (A/O)-anaerobic ammonia oxidation reactor (ANAMMOXR) was used for the advanced treatment of a mixture of municipal landfill leachate and domestic wastewater. Partial nitrification-anaerobic ammonia oxidation was employed in the system to achieve advanced nitrogen removal. The system solves the problems associated with biological treatment of landfill leachate, such as high toxicity of leachate to microorganisms, unsatisfactory organic and nitrogen removal and high cost of additional carbon source supplemented. The experiment was operated for 90 days, with an influent of a 1∶10 mixture (volume ratio) of raw leachate and domestic sewage. The corresponding concentrations of ρ(COD_Cr), ρ(NH₄+-N) and ρ(TN) were (750±30), (290±10) and (300±10) mg/L, respectively. The results showed that the final effluents of ρ(COD_Cr), ρ(NH₄+-N), and ρ(TN) were (67±5), (15±2) and (35±5) mg/L, with removal rates of 88%±1%, 95%±1% and 91%±1%, respectively. The effluent quality complied with the discharge requirements of the Standard for Pollution Control on the Landfill Sites of Municipal Solid Waste (GB 16889-2008). In addition, when the free ammonia (FA) concentration was 0.21-1.38 mg/L, FA could inhibit nitrite-oxidizing bacteria (NOB) but not ammonia-oxidizing bacteria (AOB); AOB was the dominant bacteria in the A/O reactor. Moreover, partial nitrification, with 70%-96% nitrite nitrogen accumulation rate, was achieved in the A/O reactor, which was followed by ANAMMOXR to completely remove residual ammonia and nitrite.