COD进水浓度对SBMBBR脱氮除磷效果影响

研究了序批式移动床生物膜反应器(SBMBBR)中COD进水浓度对同步脱氮除磷效果的影响.维持进水PO3-4-P浓度为10 mg/L、NH3-N浓度为40 mg/L左右,COD浓度为200～800 mg/L,研究了反应器的脱氮除磷效果.结果表明:厌氧释磷量在COD进水浓度为450 mg/L时达到最大,为61.2 mg/L;之后,增加COD进水浓度不利于磷的释放.在厌氧段初期,TN便有超过30%的损失,可能是因生物吸附造成的.好氧时TN和磷均损失较大,说明在生物膜上很可能发生了同时硝化反硝化和反硝化聚磷.一定范围的COD浓度能促进TN的去除.TN去除率在COD进水浓度为450 mg/L时达到最大,为87.8%,氮磷的去除与生物膜的生物量和生物膜厚度密切相关.

Effect of COD concentration on phosphorus and nitrogen removal in SBMBBR

The effect of different feed COD concentrations on the removal of phosphorus and nitrogen in a sequencing batch moving bed biofilm reactor (SBMBBR) was studied. The experiments were performed in the concentration of COD varying from 200 to 800 mg/L and the concentrations of nitrogen and phosphorus fixing at 40 mg/L and 10 mg/L respectively. The results show that maximal anaerobic phosphorus release of 61.2 mg/L is obtained in the condition of initial COD concentration of 450 mg/L. Increasing COD concentration is harmful to phosphorus release when COD concentration is higher than 450 mg/L. More than 30% of TN loss is observed in the initial stage of anaerobic due to biological adsorption. High TN and phosphorus removal in the aerobic indicates that simultaneous nitrification and dinitrification (SND) and dinitrification phosphorous accumulation might occur inside biofilm. A proper extent of COD promotes TN removal. Maximal removal of 87.8% of TN can be achieved at 450 mg/L of initial COD concentration. The removal of nitrogen and phosphorus is closely related to biological amount and thickness of biofilm.