Wiszniowski J, Surmacz-Górska J, Robert D, Weber J-V
The Environmental Biotechnology Department, Silesian University of Technology, Akademicka 2, 44-100, Gliwice, Poland.
J Environ Manage. 2007 Oct;85(1):59-68. doi: 10.1016/j.jenvman.2006.08.001. Epub 2006 Oct 6.
A pre-denitrification activated sludge system (AS) without internal recycle was used in lab-scale studies of landfill leachate treatment. A bentonite supplement at a ratio of 1:4 (mineral : biomass) was used to ensure high sludge settling levels and to serve as a micro-organisms carrier. The system was operated within different parameters such as hydraulic retention time (HRT), ammonia loading rate (ALR) or external recycle ratio, which was adapted to treat varying leachate concentrations of COD and ammonia, ranging from 1020 to 2680 mgO(2)l(-1) and 400-890 mgNH(4)-Nl(-1) respectively. The nitrification was complete and ammonia oxidation reached 99%; this was obtained while the ALR did not exceed 0.09 g NH(4)(+)-Ng(-1)MLVSS d(-1) and HRT was not lower than 1 day (in the aeration reactor). The performance of denitrification was successfully improved by controlling the external recycle rate, when the BOD(5)/N ratio in the raw leachate was 4.1. Consequently, N-removal of up to 80% was achieved. A 10-fold decrease in the denitrification rate was obtained at a BOD(5)/N ratio of 0.5. The efficiency of COD removal varied significantly from 36% to 84%. The positive effect of bentonite addition was determined and is discussed based on preliminary studies. The experiments were carried out in fill-and-draw activated sludge with bentonite; the biomass ratio was 1:2. The activated sludge with bentonite was fed with a synthetic high ammonia and organic-free medium.
在垃圾渗滤液处理的实验室规模研究中，使用了一种无内部循环的前置反硝化活性污泥系统（AS）。以1:4（矿物质:生物量）的比例添加膨润土，以确保高污泥沉降水平并作为微生物载体。该系统在不同参数下运行，如水力停留时间（HRT）、氨负荷率（ALR）或外部循环比，以适应处理不同浓度的化学需氧量（COD）和氨的渗滤液，其COD浓度范围为1020至2680 mgO₂l⁻¹，氨氮浓度范围为400 - 890 mgNH₄-Nl⁻¹。硝化作用完全，氨氧化率达到99%；这是在ALR不超过0.09 g NH₄⁺-Ng⁻¹MLVSS d⁻¹且HRT不低于1天（在曝气反应器中）的情况下实现的。当原渗滤液中的五日生化需氧量（BOD₅）/氮比为4.1时，通过控制外部循环率成功提高了反硝化性能。因此，实现了高达80%的氮去除率。当BOD₅/氮比为0.5时，反硝化率降低了10倍。COD去除效率在36%至84%之间有显著差异。基于初步研究确定并讨论了添加膨润土的积极作用。实验在添加膨润土的序批式活性污泥中进行；生物量比例为1:2。向添加膨润土的活性污泥中投喂合成的高氨且无有机物的培养基。
