模拟光伏间歇曝气SBR硝化特性

通过耦合农村生活污水间歇排放、SBR间歇运行和太阳能能量密度昼夜变化的特征,模拟光伏间歇曝气,考察以无蓄电池光伏间歇曝气替代常规曝气,降低污水处理设施对电网依赖的可行性,采用SBR处理经厌氧和好氧预处理的生活污水,系统研究了SBR硝化的启动特征及曝气量、HRT(水力停留时间)和温度对其运行效果的影响. 结果表明,在不同曝气量、HRT和温度下,均能实现NH₄+-N的有效去除. ρ(DO)是硝化作用的主要影响因素. 在低曝气量(曝气量为0.6 L/min、温度为20 ℃、HRT为13和16 h)及高水温(曝气量为0.8 L/min、温度为30 ℃、HRT为16 h)条件下,由于ρ(DO)(<3 mg/L)较低,NH₄+-N去除率下降,并且出现了一定程度的NO₂--N累积. 通过对ρ(DO)、pH和E_h(氧化还原电位)的监测表明,E_h变化不规律,而ρ(DO)和pH在一个运行周期内变化规律明显,与硝化进程具有较好的对应性,可将其作为实时控制参数,控制硝化曝气过程. 

Nitrification Performance of a Novel SBR Based on Stimulating Photovoltaic Intermittent Aeration

By coupling intermittent characteristics of rural sewage discharge, SBR operation and solar energy density, a simulated photovoltaic intermittent aeration system without batteries was proposed to study its feasibility to replace conventional aeration and reduce the dependence of wastewater treatment plants on the grid. SBR was utilized to treat domestic wastewater pretreated by the anaerobic/aerobic process. A systematic study of the start-up of nitrification in SBR using the novel aeration method and the influence of aeration rates, HRTs and temperatures on nitrification performance was carried out. The results showed that the removal of NH₄+-N could be achieved under different operating conditions. DO concentration was the dominant factor affecting the nitrification process. Under the low aeration rate condition (i.e., aeration rate 0.6 L/min, temperature 20 ℃, HRT 13 h and 16 h) and high water temperature condition (i.e., aeration rate 0.8 L/min, temperature 30 ℃, HRT 16 h), the DO concentration remained at a relatively low level (<3 mg/L). Therefore, the NH₄+-N removal rate decreased, and there was a certain degree of NO₂--N accumulation. Through monitoring the DO, pH and E_h, the results indicated that the E_h curves varied irregularly. However, DO and pH in one operating cycle showed obvious patterns and corresponded well with the nitrification process, so they could be used as real-time control parameters to control the nitrification aeration process.