【作者】 李文君；

【导师】 王增长；

【作者基本信息】 太原理工大学 ， 市政工程， 2008， 硕士

【摘要】 近年来,随着水体富营养化问题越来越严重,以及对污水处理中氮、磷等排放标准越来越严格的问题,急需开发出一种既脱氮效果好,又简便节能的生物脱氮工艺。序批式生物膜反应器（SBBR）是目前正在研究、应用的一种污水生物处理新工艺,它是在SBR的基础上发展起来的,既保留了SBR的诸多优点,又有不同于SBR的特点。由于SBBR工艺的脱氮效果好;自动化程度高,运行管理简单;基建费用低,运行费用省,推广到城市污水处理中,必将产生良好的环境效益和社会效益,其应用前景十分广阔。本文研究了序批式生物膜反应器（SBBR）在有氧情况下同步硝化反硝化的生物脱氮机理,并对影响SND的各种因素进行了较详细的研究。试验选用反应器为有机玻璃制成,其主要尺寸为:直径15cm、高40cm、总容积7L、有效容积6.2L。生物膜载体选用立体弹性填料,并采用高氨氮污水为处理对象;试验系统地考察了DO浓度,COD浓度（C/N）,生物膜厚度等因素对生物膜法同步硝化反硝化（SND）脱氮效果的影响。通过试验分析,得到以下主要结论:溶解氧浓度控制在2mg/L左右时,其同步硝化反硝化现象明显,脱氮效果最佳,氨氮去除率可达90%,COD_Cr的去除率达94.6%,出水总氮浓度为26.6mg/L～29mg/L,总氮的平均去除率在50%以上,最高去除率达到66.8%,并可推断出在反应系统内存在好氧反硝化菌。C/N控制在4～8之间时,C/N越高,SND效果越好,继续增加碳氮比时,总氮去除率增加不多,并且还会导致硝化作用不完全。当存在足够的易降解有机碳源时,能发生完全的好氧反硝化作用。载体生物膜具有吸附储碳能力,在较大的溶解氧浓度范围内,增加载体生物膜厚度有利于同步硝化反硝化的进行。SBBR具有同步硝化反硝化的能力,建议将NH₃-N降解到零或最小值的时刻,作为同步硝化反硝化的结束点;当原水氨氮浓度高时可增加后续脱氮处理或减少进水量来满足出水要求,或者优化运行方法和参数来稳定SBBR的总氮（TN）去除率。微环境理论和微生物学理论可以解释试验中所发生的好氧生物膜法同步硝化反硝化（SND）现象。生物膜法同步硝化反硝化作用机理可以认为,在DO浓度较低情况下,由于生物膜内部存在着溶解氧浓度梯度,从外至内生物膜可以分为好氧层、缺氧层和厌氧层。生物膜内部的缺/厌氧层存在着大量的反硝化菌,使得反硝化脱氮在这里得以进行。总之,生物膜内部溶解氧浓度梯度的存在是系统进行同步硝化反硝化的关键因素。SBBR工艺在小型点源污染控制和污水脱氮除磷深度处理中是一种行之有效的脱氮除磷工艺。更多还原

【Abstract】 As the water eutrophication becoming more and more serious, as well as the standards of nitrogen and phosphorus had been improved, It is necessary to develop a high-efficient, low energy required and simply operated technology to nutrient removal. SBBR （sequencing biofilm batch reactor） is a new wastewater biontreatment process researching at present. It is developing based at SBR and inherits SBR many merits, as well as developed the new characteristics.The prospect of the SBBR technical application has full vastitude for its good effects of nitrogen and phosphorus removal, the high automation, the simple running supervision, the low charge of the capital construction and saving the running charge. Popularized at the field of municipal sewage teatment, the technical will produce the good environment benefit and the social benefit. The character of simultaneous nitrification and denitrification of sequencing batch biofilm reactor（SBBR） under the condition of oxygen existing was studied. The paper discuss the mechanism of nitrogen removal by simultaneous nitrification and denitrification （SND） and study the various factors affecting SND in detail. In the paper, the biological reator is made of synthetic glass, Its main dimensions are: Diameter is 15cm, Height is 40cm, Volume is 7L, Working Volume is 6.2L, And the biological filler is tridimensional elastic packing. The raw wastewater is high concentration NH₄-N wastewater. The regular that the main factors such as DO, CODconcentration （or C/N ratio） affected SND had been researched. The result show that under the condition of dissolved oxygen value （DO） about 2mg/L the phenomena of simultaneous nitrification and denitrification is obvious and the denitrification effect is optimal. The removal of NH₄-N reached 90% and that of CODcr reached 94.6% in the meantime. According to the experimental result showing more than 50% TN removal, the study suggests aerobic denitrification, i.e., simultaneous nitrification and denitrification （SND）, took place during the operation. When C/N is increased, the total nitrogen removal rate increases. when C/N is 4～8, total nitrogen removal could reach the highest rate of 66.8%. When C/N increases further, nitrogen removal rate has no obvious growing, and will result in nitrifying functionin incompletely.A complete aerobic denitrification function can take place when there are enough degradable organic carbon sources.The SBBR is advantageous to create anoxic condition, and biofilm can absorb and store carbon for good nitrification and denitrification. The efficiency of simultaneous nitrification and denitrification increased with increasing of thickness of the biofilm. SBBR possessed the capacity of simultaneous nitrification and denitrification in wider range of dissolved oxygen concentration; and when NH₃-N reduced to zero or minimum value, the time was suggested to be the end of simultaneous nitrification and denitrification. It is suggested that a subsequence for denitrification is added or influent amount is decreased for requirement of effluent quality. At optimum operating parameters, the TN removal efficiency could be achieved.Based on the previous research work, it is appropriate that using the Microscopic Environmental view and the Microorganism Theory to explain the mechanism of the SND in biofilm process: at the condition of low DO concentration, because of the DO concentration gradient which exists in biofilm, the biofilm could classify three party from outside to inside: layer of oxygen, layer of oxygen deficient, anaerobic layer. Beause the layer of oxygen deficient and the anaerobic layer are consist of some facultative bacteria or anaerobic bacteria such as denitrifying bacteria, it make the denitrification to be probable. In a word, the DO concentration gradient exists in biofilm is the critical factor of SND.It was concluded that SBBR was an effective technology for simultaneously removing nitrogen during control of small scale point polluting sources and further treatment of water.更多还原