污水处理厂总氮提标多模式切换运行

Multi-Mode Switching Operation of Upgrading Standard for Total Nitrogen Removal in WWTP

针对苏州工业园区第二污水处理厂总氮(TN)指标不能稳定达到新标准的问题,设计开发出多模式切换的AAO工艺运行方式。通过多点分配进水、倒置内回流、延长缺氧区水力停留时间(HRT)以及正置、倒置等不同模式切换相结合的方式,根据季节变化对厌氧-缺氧-好氧工艺系统进行调整,优化碳源分配,寻找便于操作的高效脱氮工艺运行模式,提高脱氮效果,从而实现TN含量<10 mg/L的控制目标。试验结果表明,采取部分进水超越初沉池、延长缺氧区HRT、优化碳源分配相结合策略能较好提高工艺的脱氮效果。

To address the problem that Suzhou Industrial Park’s total nitrogen(TN) index for the Second Sewage Treatment is not consistently up to new standard, and multi-mode switching AAO process is adopted. Through the combination of different modes, such as multi-point distribution of influent, inverted internal reflux, extension of hydraulic retention time(HRT) in anoxic section, positive and inverted, the anaerobic anoxic aerobic process system was adjusted according to the seasonal changes. In order to optimize carbon source distribution and achieve the control target of TN concentration < 10 mg/L, a convenient and efficient denitrification process operation mode was found to improve denitrification effect. Experimental results showed that the combination of influent exceeding primary sedimentation tank, prolonging HRT in anoxic section and optimizing carbon source distribution could better improve the nitrogen removal effect of process.