膜-生物反应器和传统活性污泥法去除两种内分泌干扰物的对比研究

Comparison of bisphenol A (BPA) and nonylphenol ethoxylate (NPnEO) removal with a membrane bioreactor versus a conventional activated sludge reactor

采用不主动排泥的运行模式,在相同污泥负荷条件下,对比研究了膜-生物反应器(MBR)与传统活性污泥反应器(CASR)对两种典型内分泌干扰物——双酚A(BPA)与壬基酚聚氧乙烯醚(NPnEO,n=1～4)的去除效果.结果表明,在BPA-污泥负荷与NPnEO-污泥负荷分别为0.046～10.2g.kg-.1d-1与0.097～0.701g.kg-.1d-1的范围内,MBR与CASR均能有效去除这2种内分泌干扰物.随着运行时间的延长,污泥对目标物质的去除能力逐渐加强;相比CASR,MBR对目标物质的去除更强且稳定.在获得相同的出水目标物质浓度条件下,MBR可以耐受更高的容积负荷.2种内分泌干扰物的投加对MBR和CASR的COD和NH4+-N的去除均没有明显影响.

Endocrine disrupting chemicals （EDCs） are a series of microcontaminants influencing the safety of wastewater reclamation. Two typical EDCs, bisphenol A （BPA） and nonylphenol ethoxylates （ NPnEO, n = 1 - 4） , were removed by a membrane bioreactor （MBR） and a conventional activated sludge reactor （CASR） without sludge discharge. Comparison of removal rates was conducted with similar target compound - sludge loadings. The results showed that, under the conditions of 0. 046 - 10.2 g·kg^-1·d^-1 for BPA-sludge loading and 0. 097 - 0. 701 g·kg^-1·d^-1 for NPnEO-sludge loading, both the MBR and the CASR could remove BPA and NPnEO effectively. With prolonged operation, the capacity of sludge to remove target compounds was enhanced, and the MBR could achieve higher and more stable removal rates than the CASR. The MBR could hold a higher volumetric loading for target compounds than the CASR to achieve the same levels of effluent concentrations. Furthermore, the removal rates of COD and NH4^＋ -N were not affected as the target compounds were fed into both the MBR and the CASR.