不同微生物处理工艺对全氟化合物的去除效果

以辽宁省4个采用不同微生物处理工艺的污水处理厂为研究对象,采用WAX固相萃取分离富集和高效液相-质谱联用(HPLC/MS/MS)方法测定了4个污水处理厂中13种PFCs(全氟化合物)〔9种PFCAs(全氟羧酸类化合物,C₄~C₁₂)和4种PFSAs(全氟磺酸类化合物,C₄、C₆、C₈、C₁₀)〕的质量浓度. 研究发现,9种PFCAs(C₄~C₁₂)(记为∑PFCAs)和2种PFSAs(C₄、C₈)(记为∑PFSAs)均有不同程度的检出,水体中各PFCs浓度水平与碳链长度呈显著负相关. 进水中ρ(∑PFCAs)和ρ(∑PFSAs)分别为81.5~135.9和3.7~4.6 ng/L,出水中ρ(∑PFCAs)和ρ(∑PFSAs)分别为47.4~63.3和2.8~3.7 ng/L. 进、出水受PFCAs尤其是短链PFCAs污染较为严重. 4个污水处理厂对PFCs的去除呈现相似的去除效果及规律,即PFCs的去除主要靠活性污泥的吸附作用,而与污水处理厂所采用的微生物处理工艺相关性不大. 

Removal Efficiency of Perfluorinated Compounds with Different Microbial Treatment Techniques

Abstract:In order to study the effects of various treatment techniques on the removal of PFCs in wastewater and their treatment mechanisms, samples were collected from four wastewater treatment plants (WWTPs) with different treatment techniques, and were analyzed with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for PFCs. Nine perfluoroalkyl carboxylates (PFCAs, C₄-C₁₂) and two perfluoroalkyl sulfonates (PFSAs, C₄, C₈) were detected with various quantities in both the influents and effluents of WWTPs. PFC pollution levels were significantly negatively correlated with carbon chain length. The total quantities of PFCAs and PFSAs ranged from 81.5-135.9 ng/L and from 3.7-4.6 ng/L in influents, and from 47.4-63.3 ng/L and from 2.8-3.7 ng/L in effluents of different WWTPs, respectively. The removal of PFCs in wastewater showed a similar effect and regularity, which was dependent on the PFC adsorption on the activated sludge, while different microbial treatment techniques in WWTPs exerted little on the PFCs removal.