厌氧-缺氧下反硝化除磷对低碳污水的处理性能研究

采用厌氧-缺氧条件运行的序批式移动床生物膜反应器,考察了NO3--N进水浓度及其投加方式对低碳废水(COD=200mg/L)反硝化除磷的影响.经驯化后,反硝化聚磷菌(DPB)在总聚磷菌的份额从15.7%增长到71.3%,富集了DPB.NO3--N的浓度对处理有较大影响.在NO3--N为30mg/L(即C/N=6.7:1)时,COD、PO43--P和NO3--N的去除率分别为97.8%、82.0%和81.2%,实现低碳污水的高效处理.NO3--N较低或较高浓度(20mg/L和40mg/L)时,缺氧段吸磷不充分,PHB由厌氧开始时的2.2mg/g左右分别积累至5.1mg/g和3.5mg/g,影响下一周期磷的释放.1次投加、2次投加和连续流加NO3--N,除对缺氧初期的反硝化吸磷速率有影响外,对反硝化除磷的效率影响不明显.

Wastewater with Low Carbon Source Using Denitrifying Phosphorus Under Anaerobic-Anoxic Conditions

The effects of influent nitrate concentration and its adding modes on denitrifying phosphorus removal in a wastewater with low carbon (COD = 200 mg/L) using a sequencing batch moving bed biofilm reactor (SBMBBR) operated under anaerobic-anoxic conditions was investigated. After the domestication, the percentage of denitrifying phosphorus removing bacteria (DPB) in all phosphorus removing bacteria(PB) increased from 15.7% to 71.3%, indicating that DPB was enriched. Concentration of the influent nitrate had a significant effect on the treatment. At the influent nitrate concentration of 30 mg/L, i. e., C/N = 6.7 : 1, COD, PO4(3-) -P and NO3(-) -N removal increased to 97.8%, 82.0% and 81.2%, respectively, showing an efficient treatment under this low carbon. When the influent nitrate was less or more (20 and 40 mg/L), phosphorous uptake observed was insufficient in the anoxic stage, and poly-beta-hydroxybutyrate (PHB) increased from 2.2 mg/g MLSS in the initial anaerobic stage to 5.1 mg/g MLSS and 3.5 mg/g MLSS, respectively, affecting phosphorous release in the next period. Adding nitrate in one time, two times or continuous mode had little effect on the denitrifying phosphorus removal, but affected the removal rate in the initial anoxic stage.