不同基质厌氧折流-垂直流人工湿地(ABR-VFW)对农村生活污水的处理效果

Experimental study on treatment of rural domestic sewage by four substrates anaerobic baffled reactor-vertical flow wetlands(ABR-VFW)

为筛选不同污染浓度下垂直流人工湿地处理农村生活污水的最优基质,选取4种常见的基质:页岩砖渣(YYZZ)、火山岩(HSY)、生物陶粒(SWTL)和无烟煤(WYM),构建厌氧折流-垂直流人工湿地(ABR-VFW),水力负荷统一设置为4.2 m3·m^(-2)·d^(-1),通过对比分析不同污染浓度(低、中、高)下4种基质对农村生活污水中的有机物(以COD计)、总氮(TN)、总磷(TP)、铵态氮(NH_4^+-N)、硝态氮(NO-3-N)的处理效果,为垂直流人工湿地治理农村生活污水最佳基质的选取提供了合理依据。结果表明:YYZZ对污水中COD和TN的去除率最高,分别为88.12%~95.78%(低浓度)、64.05%~84.09%(中浓度)、61.25%~74.07%(高浓度)和51.98%~55.98%(低浓度)、38.52%~50.84%(中浓度)、47.42%~53.22%(高浓度),其次为WYM和HSY,而SWTL最低;SWTL对农村生活污水中NH_4^+-N和TP的去除率显著高于其他基质,其分别高12%~24%(NH_4^+-N)和13%~23%(TP)。研究表明,对COD和TN含量较高的农村生活污水以YYZZ基质去除效果为佳,而对TP或NH_4^+-N为主的农村生活污水以SWTL基质去除效果为优。

In order to select optimal substrates for artificial vertical flow wetlands（VFW）that are used to filter domestic sewage with vary-ing levels of pollution, four common substrates（i.e., shale debris, volcano ash, biological porcelain, and anthracite）were used to con-struct anaerobic baffled reactor（ABR）-VFWs. Hydraulic load was set uniformly to be 4.2 m-3·m^（-2）·d^（-1）. The effects of the four substrateswere analysed on three pollution loadings（low, medium, and high concentration）in terms of the chemical oxygen demand（COD）, total nitro-gen（TN）, total phosphorus（TP）, and ammonium nitrogen（NH4＋-N）of rural domestic sewage. The shale debris substrate reduced the CODof the low, medium, and high-pollution sewage by 88.12%-95.78%, 64.05%-84.09%, and 61.25%-74.07%, respectively, and the TN by51.98%-55.98%, 38.52%-50.84%, and 47.42%-53.22%, whereas the anthracite and volcano ash substrates were less effective, and the bio-logical porcelain was the least effective. In contrast, the biological porcelain substrate removed NH4＋-N and TP from the rural domestic sewageat significantly higher rates than the other substrates. Therefore, shale debris are the most effective substrate for purifying rural domesticwastewater with high COD or TN, whereas biological porcelain is the most effective substrate for purifying wastewater with high TP or NH4＋-N.