【作者】 吴昌永；

【导师】 陈志强；

【作者基本信息】 哈尔滨工业大学 ， 市政工程， 2006， 硕士

【摘要】 短程硝化反硝化工艺是近年来开发的一种新型生物脱氮工艺,和常规的生物脱氮工艺相比,该工艺能节省曝气量和反硝化碳源,并具有污泥生成量小等一系列优点,因而近期成为国内外的研究热点。但是短程硝化反硝化工艺的实现条件较为苛刻,常规条件下更是很难维持稳定的短程硝化反硝化。针对这些特点,本研究采用SBR反应器,运用实时控制手段,以实际生活污水作为处理对象,系统地研究了短程硝化反硝化的实现、维持、实时控制和实时控制条件下的短程硝化反硝化的稳定性。通过恒温下去除有机物的试验表明,SBR法去除有机物的过程中在线参数pH和COD之间有很强的相关性,可以通过反应过程中pH的变化特征及时调整曝气,优化曝气时间。这种相关性受曝气量的影响小,受温度的影响大,因为温度对pH有直接影响。通过建立简化的有机物去除模型表明,有机物去除初期可看作一级反应,后期可看作二级反应。在反应温度为28 0.5℃,污泥浓度为3100mg/L左右时,利用在线参数pH、DO和ORP的变化特征点实时控制曝气时间,经过长时间的运行,系统的亚硝化率从第1d的33.7%升高到第67d的93.63%。在其它条件都不变的情况下系统改为定时运行,曝气时间定为250min,经过7d的运行,已形成的短程硝化被破坏,亚硝酸盐积累率只有36.9%。经分析,这是因为定时曝气无法准确预知硝化终点,系统过量曝气所致。反应器采用实时控制常温下（平均温度为20℃）运行30d,系统的亚硝酸盐积累率平均为61.31%。系统即使没有维持在较高的温度,但通过实时控制,仍可保持较高的亚硝酸盐积累率,短程硝化没有被破坏。在实际运行过程中,在线参数的稳定性良好,受外界干扰比如曝气量变化的影响小。高NH₄⁺-N负荷的冲击试验表明,短时间的高NH₄⁺-N负荷冲击,对短程硝化没有明显影响,实时控制状态下的短程硝化具有一定的稳定性。在低溶解氧（DO）条件下,DO可以作为一种选择压力实现对亚硝化菌（AOB）的富集,对硝化菌（NOB）的淘洗,这是因为它们在生长动力学上的差异引起的。长期运行在低DO条件下,可使污泥的种群结构得到优化,维持稳定的短程硝化反硝化。SRT对污泥中AOB和NOB的数量比例也有一定的影响,在实时控制条件下,维持较长的SRT系统中NOB会得到富集,亚硝酸盐积累率下降;维持较短的SRT,AOB和NOB都不能成为优更多还原

【Abstract】 Biological nitrogen removal via nitrite is a new biological nitrogen removal process. Compared with traditional biological nitrogen removal technology, this new process can save aeration energy and denitrification carbon source, and it can also yield less waste biomass during treatment process, so it attracts more and more attentions all around the world. But the achievement of the new nitrogen removal process is very difficult, and it is more difficult to maintain high nitrite accumulation rate during ambient conditions for a long time. According to these features, the research focused on the achievement, maintenance, real time control and the feasibility of nitrite accumulation under real time control conditions. SBR reactor was used to treat real domestic wastewater during the research progress.Online parameters of pH and COD concentration were relevant during the process of organics removal by SBR reactor. We could adjust aeration in time according to the changing features of pH curve and optimize the aeration time. The relevance between pH and COD concentration was stable and not affected by aeration rate. But the changing temperature could weak the relevance, because temperature could affect pH value directly. By establishing a simpled kinetics model of organics removal we could know that the initial period of COD removal obeyed the first-order reaction and the later period of COD removal obeyed the second-order reaction. The interval between them was indistinct depending on conditions.By controlling the temperature (28±0.5℃) and maintaining the MLSS concentration (about 3100 mg/L), the bending-points of online parameters pH, DO and ORP were used to control the aerobic/anoxic alternation. The SBR reactor run for about 67 days and its nitrite accumulation rate (NO2--N/NOx--N) increased from 33.7% to 93.63%. The running model was changed from real time control to fixed time control, the nitrite accumulation rate in SBR decreased to 36.9% 7days later, and the main reasons was that the exact time of nitrification could not be controlled in time and the system was often in conditions of over aeration. The SBR reactor was operated under realtime control and normal更多还原