【作者】 汤争争；

【导师】 赵林；

【作者基本信息】 天津大学 ， 环境科学， 2007， 硕士

【摘要】 随着水体中氮污染问题的日益严重,水体中氮指标的日益严格化,短程生物脱氮由于节能、节约碳源、缩短水力停留时间和减少剩余污泥排放量等优点而颇受重视。本研究根据生物脱氮过程中的pH值变化规律,结合溶解氧(DO)的变化特征来指示硝化和反硝化反应的结束,对SBR进行实时控制,成功的实现了短程硝化反硝化。并对短程硝化反硝化的稳定性进行了研究,最后建立了短程硝化反硝化的动力学模型。试验结果如下:(1)通过考察在不同的进水氨氮浓度、不同的进水pH值以及不同的曝气量条件下,pH的变化规律都不受影响,说明了用pH作为硝化反硝化过程的控制参数是可行的。可以根据pH的特征变化对SBR反应器进行实时控制。(2)在驯化成熟的全程硝化反硝化活性污泥的基础上,通过降低溶解氧、提高进水pH值成功的实现了短程硝化反硝化,亚硝酸盐氮的积累率达到95%以上。在此基础之上,逐渐提高曝气量、降低进水的pH值,发现即使在较高的溶解氧、较低的pH条件下,短程硝化并没有被破坏,亚硝酸盐氮的积累率依然维持在95%以上,有时甚至达到100%的短程。说明菌种的驯化对短程硝化是关键,一旦亚硝化菌驯化成熟,在系统中占绝对优势,短程硝化便可以长久稳定下去。(3)实验中还发现,对反应过程进行定时控制,过度曝气容易引起短程硝化向全程硝化的转化。过度曝气4天之后,硝化类型就由亚硝酸盐积累率为95%的短程硝化转变为亚硝酸盐积累率为41.3%的全程硝化。(4)本文通过对短程硝化反应进行动力学的分析,推导出短程硝化阶段的动力学方程,并通过实验数据分析,求出其动力学参数。并通过实验值和计算值的对比,对该动力学方程进行了验证。更多还原

【Abstract】 As the nitrogen pollution in water bodies is becoming increasingly serious, and the nitrogen index becoming increasingly strict, short-cut biological nitrogen removal is regarded for its advantages, such as saving energy and carbon resource, shortening hydraulic residence time(HRT), reducing the amount of sludge-discharging, and etc.Based on the regulation of pH variation during organic oxidation, nitrifying and denitrifying in Sequencing Batch Reactor(SBR), combined with the change of Dissolved Oxygen(DO), this experiment controls the SBR in real time. This thesis is mainly on achieving short-cut nitrification-denitrification in low DO, high influent pH, and also discusses the stability of short-cut nitrification-denitrification. At the end of the thesis, the kinetic model of short-cut nitrification is proposed. The main conclusions are as follows:(1) In different influent ammonia nitrogen concentration, different influent pH value and different aeration rate, the regulation of pH is not affected, so it is feasible to judge the close of nitrification and denitrification, based on the characteristic points of pH curve.(2) Short-cut nitrification-denitrification sludge domestication is achieved successfully through lowing DO and increasing influent pH value on the basis of mature full nitrification-denitrification sludge. The accumulation rate of nitrite nitrogen can get above 95%. Then gradually increasing aeration rate, lowing influent pH, the short-cut nitrification is not destroyed in high DO, low pH conditions, the accumulation rate of nitrite nitrogen still maintained above 95%,sometimes can get 100%. This illuminates that domestication of certain bacterium is the key to short-cut nitrification. Once the nitrosomonas are mature and occupy absolute dominance, short-cut can stabilize for long time.(3) Overaeration can have short-cut nitrification change to full nitrification. On the fourth day after overaeration, the accumulation rate of nitrite nitrogen falls to 41.3% from 95%, the style of nitrification becomes full nitrification.(4) At the end, this thesis discusses the kinetic of short-cut nitrification, gets the kinetic model in the phase of short-cut nitrification, and calculated the kinetic parameters. Then validating the kinetic equation through comparing the experimental values to model values.更多还原