Escuela Internacional de Doctorado (EIDO), Campus da Auga, Campus Universitário de Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain.
Centro de Química de Vila Real (CQVR), Departamento de Química, Universidade de Trás-os-Montes e Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real, Portugal.
Int J Environ Res Public Health. 2023 Jan 30;20(3):2486. doi: 10.3390/ijerph20032486.
The large production of wine and almonds leads to the generation of sub-products, such as winery wastewater (WW) and almond skin. WW is characterized by its high content of recalcitrant organic matter (biodegradability index < 0.30). Therefore, the aim of this work was to (1) apply the coagulation-flocculation-decantation (CFD) process with an organic coagulant based on almond skin extract (ASE), (2) treat the organic recalcitrant matter through sulfate radical advanced oxidation processes (SR-AOPs) and (3) evaluate the efficiency of combined CFD with UV-A, UV-C and ultrasound (US) reactors. The CFD process was applied with variation in the ASE concentration vs. pH, with results showing a chemical oxygen demand (COD) removal of 61.2% (0.5 g/L ASE, pH = 3.0). After CFD, the germination index (GI) of cucumber and corn seeds was ≥80%; thus, the sludge can be recycled as fertilizer. The SR-AOP initial conditions were achieved by the application of a Box-Behnken response surface methodology, which described the relationship between three independent variables (peroxymonosulfate (PMS) concentration, cobalt (Co) concentration and UV-A radiation intensity). Afterwards, the SR-AOPs were optimized by varying the pH, temperature, catalyst type and reagent addition manner. With the application of CFD as a pre-treatment followed by SR-AOP under optimal conditions (pH = 6.0, [PMS] = 5.88 mM, [Co] = 5 mM, T = 343 K, reaction time 240 min), the COD removal increased to 85.9, 82.6 and 80.2%, respectively, for UV-A, UV-C and US reactors. All treated wastewater met the Portuguese legislation for discharge in a municipal sewage network (COD ≤ 1000 mg O/L). As a final remark, the combination of CFD with SR-AOPs is a sustainable, safe and clean strategy for WW treatment and subproduct valorization.
大量生产葡萄酒和杏仁会产生副产品，如酿酒废水（WW）和杏仁皮。WW 的特点是含有大量难生物降解的有机物（生物降解性指数<0.30）。因此，本工作的目的是：（1）应用基于杏仁皮提取物（ASE）的有机混凝剂进行混凝-絮凝-沉淀（CFD）处理，（2）通过硫酸根自由基高级氧化工艺（SR-AOPs）处理有机难降解物质，（3）评估 CFD 与 UV-A、UV-C 和超声（US）反应器相结合的效率。CFD 工艺应用于 ASE 浓度与 pH 值的变化，结果表明 COD 去除率为 61.2%（ASE 为 0.5g/L，pH=3.0）。CFD 后，黄瓜和玉米种子的发芽指数（GI）≥80%；因此，污泥可回收作肥料。SR-AOP 的初始条件是通过应用 Box-Behnken 响应面法来实现的，该方法描述了三个独立变量（过一硫酸盐（PMS）浓度、钴（Co）浓度和 UV-A 辐射强度）之间的关系。之后，通过改变 pH 值、温度、催化剂类型和试剂添加方式对 SR-AOPs 进行优化。采用 CFD 作为预处理，然后在最佳条件下（pH=6.0、[PMS]=5.88mM、[Co]=5mM、T=343K、反应时间 240min）进行 SR-AOP，COD 去除率分别提高到 UV-A、UV-C 和 US 反应器的 85.9%、82.6%和 80.2%。所有处理后的废水均符合葡萄牙排放到城市污水管网的法规（COD≤1000mg O/L）。最后，CFD 与 SR-AOPs 的结合是一种可持续、安全、清洁的 WW 处理和副产物增值策略。
