硫铁填料和微电流强化再生水脱氮除磷的研究

为提高再生水质量,在不同C/N和HRT条件下,对比分析硫铁复合填料和微电流作用强化再生水深度脱氮除磷效果.结果表明,硫铁复合填料和微电流作用均能够强化氮、磷的深度去除效果,且二者结合能够使反硝化系统pH值稳定在7.2~8.5之间.系统中TN主要靠异养反硝化、氢自养反硝化和硫自养反硝化作用去除,94.04%的TP是以生成磷酸铁沉淀的形式去除.分别从填料上取生物膜,进行Miseq高通量测序,构建细菌16S rRNA基因克隆文库.结果发现,在仅有海绵铁作用系统中,同时具有异养反硝化和氢自养反硝化功能的细菌所占比例达到29.47%;硫铁复合填料和硫铁微电流作用系统中,具有硫自养反硝化功能的Thiobacillus(硫杆菌属)所占比例分别达到60.47%和40.62%.因此,硫铁复合填料和微电流作用用于强化再生水深度脱氮除磷具有明显的优势.

Research on enhanced denitrification and phosphorus removal from reclaimed water by useing sponge iron/sulfur composite fillers and low electrical current

In order to improve the quality of reclaimed water, a comparative study was conducted under different C/N and HRT conditions to examine the effect on advanced nitrogen and phosphorus removal by using sponge iron/sulfur composite fillers and low electrical current. The results indicated that both the sponge iron/sulfur composite fillers and low electrical current treatment can strengthen the removal efficiency of nitrogen and phosphorus, and their combination can further stabilize the pH value of 7.2~8.5 in the denitrification system. It was found that the removal of total nitrogen (TN) was mainly depended on the process of heterotrophic denitrification, hydrogen autotrophic denitrification and sulfur autotrophic denitrification, while 94.04% of the total phosphorus (TP) were removed in the form of iron-phosphate precipitation. Furthermore, biofilm was taken from the fillers to build the bacterial 16S rRNA gene clone library by adopting the high-throughput sequencing technologies. The results showed that the bacteria which can use both organic carbon and elemental hydrogen as its electron donor for denitrification accounted for 29.47% of the bacterial community in the sponge iron fillers system. The proportion of Thiobacillus bacteria which can use elemental sulfur as its electron donor reached 60.47% and 40.62% of the bacterial community in the system of sponge iron/sulfur composite fillers and the combined system of composite fillers with low electrical current, respectively.Therefore, there are obvious advantages of employing sponge iron/sulfur composite fillers and low electrical current to enhance the effect of advanced nitrogen and phosphorus removal from reclaimed water.