Abstract

In this study, the behaviors of amoxicillin and ciprofloxacin were investigated in the conventional treatment systems in both theoretical and experimental manner. The doses of these pharmaceuticals which inhibit the treatment were determined. The efficiencies of amoxicillin and ciprofloxacin in response to dose increments were determined by monitorization of chemical oxidation demand parameter. Based on the results of these studies, amoxicillin doses >35 mg/L and ciprofloxacin doses >10 mg/L reduced treatment efficiency by leading changes in the structure of activated sludge. The sludge became sticky and dark due to the increase in the extracellular polymeric substance formation in the bacteria with increasing pharmaceutical concentration. The highest and lowest removal efficiencies were found as 39.8 and 14.9% for amoxicillin doses of 5 and 20 mg/L, respectively. The greatest part of the removal efficiency was achieved through adsorption in the sludge (33.8%). On the other hand, the highest and lowest removal efficiencies were found as 15.17 and 2.85% for ciprofloxacin doses of 30 and 75 mg/L, respectively. Again, the greatest part of the removal efficiency was achieved through adsorption in the sludge (11.83%). This indicates that removal mechanisms for both pharmaceuticals were sludge adsorption as amoxicillin and ciprofloxacin biodegradations were low at all doses investigated. To compare experimental data with theoretical estimations, pharmaceutical removal was calculated in Sewage Treatment Plant (STP) using EPI Suite program. According to experimental results, the total removal efficiencies were consistent with theoretical estimations calculated by Environmental Protection Agency (EPA) Draft Method. There may be inconsistency between theoretical estimations and experimental results due to differences in experimental conditions caused by microbiological behaviors in the theoretical conditions. The removal efficiencies for amoxicillin and ciprofloxacin calculated by default method were lower than those calculated by EPA draft method since biodegradability is not taken into consideration in the default method.

中文翻译：

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序批式反应器中阿莫西林和环丙沙星的行为及其对化学需氧量去除效率的影响研究

摘要

在这项研究中，阿莫西林和环丙沙星的行为在常规治疗系统中以理论和实验方式进行了研究。确定抑制治疗的这些药物的剂量。通过监测化学氧化需求参数来确定阿莫西林和环丙沙星响应剂量增量的效率。根据这些研究的结果，阿莫西林剂量 >35 mg/L 和环丙沙星剂量 >10 mg/L 通过导致活性污泥结构发生变化而降低了处理效率。由于随着药物浓度的增加，细菌中细胞外聚合物形成的增加，污泥变得粘稠和发黑。最高和最低的去除效率分别为 39.8 和 14。9% 的阿莫西林剂量分别为 5 和 20 mg/L。去除效率的最大部分是通过污泥中的吸附来实现的（33.8%）。另一方面，对于 30 和 75 mg/L 的环丙沙星剂量，最高和最低的去除效率分别为 15.17% 和 2.85%。同样，去除效率的最大部分是通过污泥中的吸附来实现的（11.83%）。这表明两种药物的去除机制都是污泥吸附，因为在所有研究剂量下，阿莫西林和环丙沙星的生物降解率都很低。为了将实验数据与理论估计值进行比较，使用 EPI Suite 程序在污水处理厂 (STP) 中计算药物去除量。根据实验结果，总去除效率与环境保护署 (EPA) 草案方法计算的理论估计值一致。由于理论条件下微生物行为造成的实验条件差异，理论估计与实验结果可能存在不一致。由于默认方法未考虑生物降解性，默认方法计算的阿莫西林和环丙沙星去除效率低于 EPA 草案方法计算的去除效率。