UASB1-A/O-UASB2深度处理垃圾渗滤液

针对传统垃圾渗滤液生物处理TN去除率低、投加碳源成本高的问题,采用UASB1-A/O-UASB2(单级上流式厌氧污泥床+缺氧/好氧+后置上流式厌氧污泥床)工艺处理实际垃圾渗滤液,实现NH₄+-N和TN的同步深度脱除,并且定量解析了A/O反应器实现并维持稳定短程硝化的影响因素. 结果表明:以V(垃圾渗滤液)∶V(生活污水)为1∶5的混合液作为进水,其ρ(COD_Cr)、ρ(TN)和ρ(NH₄+-N)分别为1 700~1 800、660~700和650~680 mg/L,最终出水COD_Cr、TN和NH₄+-N去除率均在95%以上,出水ρ(TN)为38 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. 在好氧反应器中,FA(游离氨)与FNA(游离亚硝酸)对NOB(硝化细菌)的联合抑制作用是实现NO₂--N积累率稳定在80%以上的主要原因,而产生的NO₂--N和NO₃--N可在UASB2中以难降解的有机物为碳源,通过反硝化途径被去除. 研究显示,组合系统可实现对TN的深度去除. 

Advanced Treatment of Landfill Leachate Using the UASB1-A/O-UASB2

Abstract: A combined process of a stage upflow anaerobic sludge blanket (UASB1), an anoxic/aerobic (A/O) reactor and a rear UASB (UASB2) was used to treat actual landfill leachate. This process only used the residual organic matter and internal carbon as the carbon source to completely remove the organic matter, total nitrogen and ammonia nitrogen. The factors affecting the partial nitrification were also investigated. The influent leachate of the system was mixed by raw leachate and domestic wastewater in a ratio of 1:5. The organic matter, total nitrogen and ammonia nitrogen of the influent leachate of the system were about 1700-1800,0-700 and 650-680 mg/L, respectively. The experimental results showed that the organic matter, total nitrogen and ammonia nitrogen removal efficiencies were higher than 95%, and the total nitrogen concentration of final effluent was about 38 mg/L, which was less than the requirement of the latest national emission standard. In addition, the combined inhibition action of the FA (free ammonia) and FNA (free nitrite acid) to the NOB was the major reason for the stable partial nitrification higher than 80% of the nitrite accumulation ratio in the A/O reactor. On the whole, the integrative process could completely remove the nitrite and nitrate produced by the nitrification in the aerobic zone of the A/O reactor and realize advanced nitrogen removal.