Park E, Mancl K M, Tuovinen O H, Bisesi M S, Lee J
Division of Environmental Health Sciences, College of Public Health, Ohio State University, Columbus, OH, USA.
Department of Food, Agricultural and Biological Engineering, Ohio State University, Columbus, OH, USA.
J Appl Microbiol. 2016 Dec;121(6):1777-1788. doi: 10.1111/jam.13288. Epub 2016 Oct 24.
A batch chlorination system was optimized for on-site wastewater treatment and reuse system (OWRS) and its efficiency was evaluated for reducing viruses, protozoa, bacteria and antimicrobial resistance in cold and warm seasons.
The OWRS performance in reducing microbial contaminants was determined by assessing three different faecal indicators (Escherichia coli, F-specific coliphages and Clostridium perfringens for measuring the disinfection efficiency of bacteria, viruses and spore-formers and surrogate for protozoa, respectively) using culture-based methods. Quantitative PCR was used to quantify pathogenic bacteria (Shiga-toxin-producing E. coli (STEC), Campylobacter spp., and Arcobacter spp.), a human-associated faecal marker (gyrB), and tetracycline resistant bacteria (tetQ). The levels of E. coli, coliphages and Cl. perfringens showed 5·4, 2·3, 2·5 log reduction, respectively, upon disinfection. In the final effluents, coliphages (1·7 × 10 PFU 100 ml ) and Cl. perfringens (3·4 CFU 100 ml ) were detected in 80 and 100% of the samples, but E. coli was not found. The removal and inactivation of E. coli and Cl. perfringens were not significantly different across the seasons, however, efficacy of removal and inactivation of F-specific coliphage was significantly reduced during the winter/spring season compared to the summer/autumn season (P = 0·009). The reduction of Arcobacter, gyrB and tetQ by 3·1, 2·3 and 2·3 log, respectively, was mostly due to peat biofiltration under the study conditions.
This study demonstrated that peat biofiltration was the most important step of the OWRS to remove microbes and genes from wastewater before spray irrigation of the effluents. The irrigation system is not suitable for edible crops because of the potential presence of residual pathogens.
On-site wastewater treatment systems are a practical option for reusing the wastewater for landscape, especially for those areas where geological and seasonal limitations impact the removal of microbial contaminants by soil infiltration.
对一种批式氯化系统进行优化，用于现场废水处理与回用系统（OWRS），并评估其在寒冷和温暖季节减少病毒、原生动物、细菌及抗微生物耐药性方面的效率。
通过使用基于培养的方法评估三种不同的粪便指示物（分别为大肠杆菌、F 特异性噬菌体和产气荚膜梭菌，用于测量细菌、病毒和芽孢形成菌的消毒效率以及作为原生动物的替代指标）来确定 OWRS 在减少微生物污染物方面的性能。采用定量 PCR 对病原菌（产志贺毒素大肠杆菌（STEC）、弯曲杆菌属和弓形杆菌属）、一种与人类相关的粪便标志物（gyrB）和四环素抗性细菌（tetQ）进行定量。消毒后，大肠杆菌、噬菌体和产气荚膜梭菌的水平分别降低了 5.4、2.3、2.5 个对数。在最终出水中，80%和 100%的样本中检测到噬菌体（1.7×10 PFU/100 ml）和产气荚膜梭菌（3.4 CFU/100 ml），但未检测到大肠杆菌。大肠杆菌和产气荚膜梭菌的去除和灭活在不同季节无显著差异，然而，与夏/秋季节相比，冬季/春季 F 特异性噬菌体的去除和灭活效果显著降低（P = 0.009）。在研究条件下，弓形杆菌、gyrB 和 tetQ 分别降低 3.1、2.3 和 2.3 个对数，主要归因于泥炭生物过滤。
本研究表明，泥炭生物过滤是 OWRS 在对出水进行喷灌前从废水中去除微生物和基因的最重要步骤。由于可能存在残留病原体，该灌溉系统不适用于食用作物。
现场废水处理系统是将废水用于景观回用的一种实用选择，特别是对于那些地质和季节限制影响土壤渗透去除微生物污染物的地区。
