人工快渗污水处理系统水力负荷周期的设计

Design of hydraulic loading cycle for constructed rapid infiltration wastewater treating systems

人工快渗(CRI系统)源自快速渗滤污水土地处理系统(RI系统),并沿用了其中的干湿交替工作方式,因此, 水力负荷周期同样也成为CRI系统的重要设计参数,也是系统设计的一大难点。目前CRI系统水力负荷周期的设计,不仅需要根据已有的经验,而且还要通过一段调试运行才能确定,设计过程中缺乏理论依据和设计原则。为此,笔者研究了CRI与RI系统两者之间的差异,充分考虑水力负荷周期调整对CRI系统运行的各方面影响,分别从防止NH4 N穿透和保证系统NH4 N充分硝化两个角度,提出了水力负荷周期中淹水时间和落干时间确定新方法,并通过松岗试验实例进行了初步验证,为今后CRI系统水力负荷周期的设计提供了有效的理论依据和设计原则。

The constructed rapid infiltration wastewater treating system (CRI) is developed from the rapid infiltration system (RI), in which the working methodology of flooding and drying is also adopted. Therefore, the hydraulic loading cycle (HLC) is an important parameter in CRI's design. This design is as difficult as that of a RI system. Presently, most HLCs obtained in CRI systems are based on experience and debugging in a considerable period of time, and there is a lack of theoretical basis and principles. In this paper, differences between CRI systems and RI systems are studied, and each aspect affected by HLC adjustment in CRI system is analyzed . Then, a new method of HLC design is put forward. In this new method, the flooding period should be small enough to avoid from NH_4-N breakthrough, and the drying period should be large enough to guarantee the nitrification of most NH_4-N complete. This method has been proved effective in the Songgang CRI experiment.It offers not only a useful method but also the theoretical basis and principles for HLC design in CRI systems.