潮汐流人工湿地中生物蓄磷的强化及其稳定性

Improvement of phosphorus bioaccumulation in a tidal flow constructed wetland and its stability

通过改进潮汐流人工湿地(TFCW)的运行方式,开展了TFCW中生物蓄磷作用的强化及其稳定性研究.结果表明,两段进水潮汐流运行方式有利于TFCW中聚磷菌群(PAOs)的富集,进而可强化湿地中的生物蓄磷作用;采用周期性补充碳源的磷移除操作可诱导生物膜中的PAOs充分释磷,避免系统中磷素的过量积累,同时可增加PAOs胞内内源性碳源的含量,强化系统中的生物蓄磷作用并有利于系统除磷效果的稳定;当生物蓄磷/碼移除(PB-PH)周期时长为30d时,TFCW在生物蓄磷过程中的磷素去除率可达96.04%,而其在磷移除过程中的磷素移除率和补充碳源利用率亦分别可达70.45%和98.22%.此时,PAOs的过量吸磷作用成为湿地系统除磷的主要途径.

Improvement of phosphorus bioaccumulation in a tidal flow constructed wetland(TFCW)and the stability ofthe system were investigated during domestic sewage treatment.Polyphosphate-accumulating organisms(PAOs)couldbecome dominant populations quickly in a modified TFCW adopting two-time feeding tidal flow operation mode,andphosphorus bioaccumulation of the system could be enhanced accordingly.The introduction of periodical carbon sourcesupplements for phosphorus harvesting was conductive to boot a deeply release of the accumulated phosphorus in PAOswhich could avoid excessive accumulation of phosphorus in the system.Meanwhile,the storage of endogenous carbonsource within the biofilm increased because of the measure which was conductive to the subsequent biological phosphorusremoval and the system stability.As the cycle length for phosphorous harvesting was30d,the phosphorus removal rate ofthe TFCW could reach96.04%during the phosphorus bioaccumulation process.And the phosphorus harvesting efficiencyand the supplementary carbon source utilization rate of the TFCW could also achieve70.45%and98.22%respectivelyduring the phosphorus harvesting process.In this case,luxury phosphorus uptake by PAOs played the greatest role inphosphorus removal.