Verdini Federico, Desogus Nicolò, Calcio Gaudino Emanuela, Cravotto Giancarlo
Department of Drug Science and Technology, University of Turin, via P. Giuria 9, 10125 Torino, Italy.
Department of Drug Science and Technology, University of Turin, via P. Giuria 9, 10125 Torino, Italy.
Ultrason Sonochem. 2025 Jul 22;120:107468. doi: 10.1016/j.ultsonch.2025.107468.
Salicylic acid (SA), widely used in dermatological pharmaceuticals and as a primary metabolite of aspirin, is frequently detected in wastewater treatment plants (WWTPs) at concentrations between 3 and 900 mg/L. Given the ECHA's predicted no-effect concentration (PNEC) of 162 mg/L for sewage treatment plants (STPs), high SA levels pose a risk to microbial communities responsible for biological oxidation. This study explores an innovative hybrid advanced oxidation process (AOP) that combines hydrodynamic cavitation (HC) and electrical discharge (ED) plasma for SA degradation, targeting environmentally friendly pretreatment before secondary biological treatment. Experiments were conducted at the pilot scale (5 L volume, 330 L/h flow rate) using model solutions with SA concentrations of 40 and 80 mg/L. While SA is typically used as a chemical dosimeter for hydroxyl radical (•OH) quantification in cavitational processes, its rapid degradation under HC/ED plasma prevents such use in this setup. For comparison, lab-scale ultrasound (US)-assisted treatments (500 kHz, 250 W, 0.1 L) were performed as a benchmark. HC/ED plasma treatment achieved over 98 % SA removal in both deionized and tap water within 20 min, whereas US treatment achieved only 54 % and 37 % removal after 120 min. Energy yield and electrical energy per order (EEO) analyses revealed that HC/ED is significantly more energy-efficient than US, particularly in tap water. Finally, the HC/ED method was evaluated through a Technology Readiness Level (TRL) assessment to estimate its scalability and applicability in real WWTP scenarios.
水杨酸（SA）广泛应用于皮肤科药物中，并且是阿司匹林的主要代谢产物，在污水处理厂（WWTPs）中经常被检测到，其浓度在3至900毫克/升之间。鉴于欧洲化学品管理局（ECHA）预测污水处理厂（STPs）的无效应浓度（PNEC）为162毫克/升，高浓度的SA对负责生物氧化的微生物群落构成风险。本研究探索了一种创新的混合高级氧化工艺（AOP），该工艺将水力空化（HC）和放电（ED）等离子体结合用于SA降解，目标是在二级生物处理之前进行环境友好型预处理。使用SA浓度为40和80毫克/升的模型溶液在中试规模（体积5升，流速330升/小时）下进行实验。虽然SA通常用作空化过程中羟基自由基（•OH）定量的化学剂量计，但它在HC/ED等离子体作用下的快速降解使得在该装置中无法如此使用。为了进行比较，作为基准进行了实验室规模的超声（US）辅助处理（500千赫，250瓦，0.1升）。HC/ED等离子体处理在20分钟内使去离子水和自来水中的SA去除率均超过98%，而超声处理在120分钟后仅实现了54%和37%的去除率。能量产率和每级电能（EEO）分析表明，HC/ED比超声处理具有显著更高的能源效率，尤其是在自来水中。最后，通过技术就绪水平（TRL）评估对HC/ED方法进行了评估，以估计其在实际污水处理厂场景中的可扩展性和适用性。
