RT Dissertation/Thesis
T1 Winery wastewater treatment by coagulation-flocculation and Advanced Oxidation Processes (AOPs): water reuse and sustainability for cellars
T2 Tratamiento de aguas residuales de la producción de vino mediante coagulación-floculación y Procesos de Oxidación Avanzados (AOP): reutilización del agua y sostenibilidad para las bodegas.
A1 Jorge, Nuno
K1 3308.10 Tecnología de Aguas Residuales
K1 3308.06 Regeneración del Agua
K1 3308 Ingeniería y Tecnología del Medio Ambiente
AB Wine industry is one of the largest marketplaces in agricultural production around the world, with a global production of around 265 million of hL in 2015. From wine processing are generated wastewaters characterized by a high organic load with a large phenolic content and low biodegradability due to the presence of dissolved suspended and colloidal particles, requiring a suitable treatment to reduce their impact on water quality, if released in water courses or reused into facilities. Physicochemical treatments such as coagulation-flocculation (CF) are based on particle interaction forces, which determine the dynamics and stability of suspensions. The process is cost effective, easy to operate and energy saving. In general CF is performed with the addition of metal agents (aluminium and iron salts), into effluents for destabilization, adsorption and precipitation of the colloidal material. A low exploited alternative are oenological and natural origin coagulants (bentonite and Acacia verek), which have several advantages such as biodegradability, sustainability, low toxicity, low residual sludge production, operate at acidic and neutral pH and are cost effective.Advanced Oxidation Processes (AOPs) have emerged as an important class of technologies in water and wastewater treatment. AOPs include photolysis, ozonation, Fenton, photo-Fenton, electro-Fenton, anodic oxidation, ultrasounds, wet oxidation and photocatalysis. The addition of UV to Fenton’s process could be interesting due to its capacity to influence the direct formation of OH radicals. Homogeneous catalysis requires further removal of the catalyst, especially in those cases where the active substance, presents toxic properties. Compared with traditional Fenton process, heterogeneous Fenton has good stability, wide pH working range, catalyst recyclability, no sludge formation avoiding the addition of a polluting soluble metal salt on the effluent.To improve AOPs efficiency, it is proposed an alternative to hydrogen peroxide (HP), such as peracetic acid (PAA) and activated sodium percarbonate (SPC). It is also proposed the formation of iron-organic acids complexes, which has been investigated to have greater advantages.An alternative to Fenton, are oxidative processes with sulfate radicals (SR-AOPs). SR-AOPs are based on the addition of oxidants possessing O-O bond, known as peroxide. Two of the most used are peroxymonosulfate (PMS) and peroxydisulfate (PDS). PMS has higher oxidation potential (1.82V) than hydrogen peroxide (1.78V).  PDS is cheaper, more stable than H2O2 and has larger bond length (1.497 Aº) than PMS (1.460 Aº).Ozonation processes are based on two possible pathways: the reactions with molecular ozone and the reactions with hydroxyl radicals produced by ozone decomposition. Ozonation and ozonation in combination with UV-C radiation and/or peroxidation have been shown to be effective in the treatment of wastewater with polyphenol content, since there is higher selectivity of molecular ozone towards polyphenols.Electrochemical advanced oxidation processes (EAOPs), are based on Fenton’s chemistry. These eco-friendly techniques possess some exciting advantages such as high versatility, excellent efficiency, high amenability and environmental compatibility for the removal of persistence organic pollutants. EAOPs include direct electrochemical oxidation methods, commonly referred as anodic oxidation (AO), and indirect electro-oxidation (IEO). Following this line of research, the purpose of this thesis is to develop chemical wastewater treatment technologies, promoting the reuse of water, sludge recovery, increasing economic sustainability and environmental protection in winery facilities. The main objective is to explore oenological coagulants applied on coagulation-flocculation in combination with AOPs, for reduction of turbidity, total suspended solids, total phenolic compounds, color, COD and TOC.
LK http://hdl.handle.net/11093/5075
UL http://hdl.handle.net/11093/5075
LA eng
NO Fundação para a Ciência e a Tecnologia | Ref. UIDB/00616/2020
DS Investigo
RD 09-oct-2024