Ultrasonic (US) and UV-C disinfection technologies have been successfully used in wastewater treatment plants (WWTPs) for disinfection purposes. The US technology is typically used as a pre-treatment step to break down larger particles and make them more susceptible to disinfection. The UV-C technology is commonly used as a final disinfection step in many WWTPs. The study aimed to assess the potential of using Zinc Oxide (ZnO) Nanoparticles (NPs) to improve the effectiveness of UV-C and US disinfection methods in treating wastewater effluent, offering a more comprehensive solution to wastewater treatment. In this experimental study, a Laboratory US Bath (40$$kHz) and a UV-C lamp (16$$W) were used. In order to investigate the effectiveness of ZnO NPs in the reduction of microbial load, 5$$mg/L of ZnO NPs was added to the effluent samples. Then, samples were examined for Total Coliform (TC) and Fecal Coliform (FC) reduction by the standard MPN/100$$mL test. The Chick‘s law was used to calculate the efficiency of microbial load. The relationship between variables was determined by regression analysis using Excel and SPSS-ver 21 software. In this study, the samples were examined in three groups: Samples that were only exposed to sonication or received UV-C radiation with Turbidity of 18 NTU (Group A) and Turbidity of 5 NTU (Group B), and Samples that received 5$$mg/L of ZnO NPs (Group C). By increasing the time from 0.5$$min to 10$$min in the presence of UV-C, the amount of microbial population decreased, and 2$$min was considered the optimal time. The maximum removal efficiencies by US for TC were 74.07,77.7, 85.1% (40${}^{\circ }$C) and 92.5,100, and 100% (60${}^{\circ }$C) in group A (in 30$$min sonication), 85.7, 85.7, 100% (40${}^{\circ }$C), respectively, and were 100% in other groups (B and C), respectively. The maximum removal efficiencies by US for FC were 76.4%, 88.2%, and 100% (40${}^{\circ }$C) and 88.2%, 100%, and 100% (60${}^{\circ }$C) in group A (in 30$$min sonication), respectively, and were 100% in other groups (B and C). In this study, an important increase in the disinfection ability of ZnO NPs has been observed in the presence of US and UV-C. So, the ZnO NPs/UV-C and ZnO NPs/US processes are valuable alternatives to conventional disinfection processes by over 90% improvement of disinfection efficiency.

超声波（美国）和 UV-C 消毒技术已成功用于废水处理厂 (WWTP) 的消毒目的。美国技术通常用作预处理步骤，以分解较大的颗粒并使它们更容易消毒。 UV-C 技术通常用作许多污水处理厂的最终消毒步骤。该研究旨在评估使用氧化锌 (ZnO) 纳米颗粒 (NP) 提高 UV-C 和美国消毒方法处理废水废水效果的潜力，为废水处理提供更全面的解决方案。在这项实验研究中，美国巴斯实验室 (40$$kHz）和 UV-C 灯（16$$W）被使用。为了研究 ZnO NPs 在减少微生物负荷方面的有效性，5$$mg/L 的 ZnO NPs 添加到流出物样品中。然后，按照标准 MPN/100 检查样品的总大肠菌群 (TC) 和粪大肠菌群 (FC) 减少情况$$毫升测试。奇克定律用于计算微生物负荷的效率。使用 Excel 和 SPSS-ver 21 软件通过回归分析确定变量之间的关系。在本研究中，样品分为三组进行检查：仅暴露于超声处理或接受 UV-C 辐射的样品，浊度为 18 NTU（A 组）和浊度为 5 NTU（B 组），以及接受 5 NTU 辐射的样品。$$mg/L ZnO NP（C 组）。通过将时间从 0.5 开始增加$$分钟到 10$$分钟，在 UV-C 存在下，微生物数量减少，2$$min 被认为是最佳时间。美国对TC的最大去除效率分别为74.07、77.7、85.1%（40${}^{\circ }$C) 和 92.5,100, 和 100% (60${}^{\circ }$C）A组（30$$分钟超声处理）、85.7、85.7、100%（40${}^{\circ }$C) 分别为 100%，其他组（B 和 C）分别为 100%。美国对 FC 的最大去除效率分别为 76.4%、88.2% 和 100%（40${}^{\circ }$C) 和 88.2%、100% 和 100% (60${}^{\circ }$C）A组（30$$分钟超声处理），其他组（B 和 C）为 100%。在这项研究中，在 US 和 UV-C 存在的情况下，观察到 ZnO NP 的消毒能力显着增加。因此，ZnO NPs/UV-C 和 ZnO NPs/US 工艺是传统消毒工艺的有价值的替代品，其消毒效率提高了 90% 以上。