脉冲SBR处理城市污水深度脱氮的工艺特性

采用脉冲式SBR法,对城市污水进行了深度脱氮试验研究.从理论上分析了进水次数和进水量对脉冲式SBR工艺运行特性的影响,得出了脱氮效率公式,并通过试验研究了这些因素对工艺运行的实际影响.理论分析表明,在不投加外碳源的情况下,随着进水次数的增加,脱氮效率依次增加.根据进水C/N的高低,进水方式可分为不等量递增进水、等量进水和不等量递减进水.试验表明,当原水中有机碳源充足时,不等量递减的进水方式相对于等量的进水方式投加较少的外碳源就能实现深度脱氮;随着进水次数的增加,外碳源的投量依次减少,但操作变得复杂,对于普通的城市污水建议采用3次等量的进水方式.采用脉冲式SBR只需投加少量外碳源就可以使处理后的城市污水出水TN低于2mg/L,TN平均去除率达到97.3%.

The characteristics of the pulsed SBR for advanced nitrogen removal of municipal wastewater

The pulsed SBR, a novel technique was adopted to test the advanced nitrogen removal with real municipal wastewater. The influence of feed frequency and amount on the operational characteristics of pulse SBR technique was studied theoretically and the nitrogen removal efficiency formula was obtained; and the practical influence of these factors on the process operation was studied through test. Theoretical studies showed that under the condition without adding external carbon source, the nitrogen removal efficiency increased with increasing feed frequency. The feed modes would be divided as increasing feed, equal feed and decreasing feed based on the influent C/N ratio. The experiments showed that decreasing feed mode could achieve advanced nitrogen removal when organic carbon in the influent was sufficient with less external carbon source required than that of equal feed model. With increasing feed frequency, the external carbon source dosage decreased; but the operation became complex, 3 step of equal feed mode was recommended for common municipal waste water. Adopting the pulsed SBR only requiring small amount of external carbon source, the effluent TN of municipal waste water could be less than 2mg/L after treating, the TN removal efficiency reached 97.3%.