Depto. de Hidráulica e Saneamento, Escola de Engenharia de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense, No. 400, 13566-590 São Carlos, SP, Brazil.
J Environ Manage. 2013 Oct 15;128:169-72. doi: 10.1016/j.jenvman.2013.05.011. Epub 2013 Jun 2.
Linear alkylbenzene sulfonate (LAS) is an anionic surfactant used in cleaning products, which is usually found in wastewaters. Despite the greater LAS removal rate related to a lower concentrations of volatile fatty acids (VFA), the influence of different ranges of VFA on LAS degradation is not known. LAS degradation was evaluated in upflow anaerobic sludge blanket (UASB) and expanded granular sludge bed (EGSB) reactors at different ranges of VFA concentrations. The reactors were fed with a synthetic wastewater containing LAS (14 mg/L). A greater LAS removal rate (40-80%) was related to the lower and narrower range of acetic acid concentration (1-22 mg/L) in the EGSB reactor. In the UASB reactor, the acetic acid concentrations presented a wider range (2-45 mg/L), and some low LAS removal rates (around 20-25%) were observed even at low acetic acid concentrations (<10 mg/L). The high recirculation rate in the EGSB reactor improved substrate-biomass contact, which resulted in a narrower range of VFA and greater LAS removal rate.
直链烷基苯磺酸钠（LAS）是一种用于清洁产品的阴离子表面活性剂，通常存在于废水中。尽管挥发性脂肪酸（VFA）浓度较低时，LAS 的去除率更高，但不同范围的 VFA 对 LAS 降解的影响尚不清楚。在不同 VFA 浓度范围内，通过上流式厌氧污泥床（UASB）和膨胀颗粒污泥床（EGSB）反应器评估了 LAS 的降解情况。这些反应器以含有 LAS（14mg/L）的合成废水为食。在 EGSB 反应器中，较低且较窄范围内的乙酸浓度（1-22mg/L）与更高的 LAS 去除率（40-80%）有关。在 UASB 反应器中，乙酸浓度范围较宽（2-45mg/L），即使在较低的乙酸浓度（<10mg/L）下，也观察到一些较低的 LAS 去除率（约 20-25%）。EGSB 反应器中的高循环率改善了底物-生物量接触，从而使 VFA 范围变窄，LAS 去除率更高。
