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During a 16 months period, the characteristics of the wastewaters generated in a Rias Baixas winery (Spain) producing white wine were determined: The characterization study showed that white wine wastewater had an average CODt and TSS values of 7.3 and 5.2 kg/m³, respectively being the ratio wastewater/wine produced of about 1.6-2.0 L/L and the ratio between load pollution and produced wine of 9.7 kgCODt/m³ WINE. A strategy for the management of wastes and wastewaters allowed for an important reduction of a 55% of wastewater generation to be achieved. In order to select a suitable technology for the treatment of wastewaters two configurations were tested at pilot scale: i) An Anaerobic Filter (AF) of 430 L followed by an activated sludge unit of 510 L and: ii) one activated sludge unit of 510 L. The results showed that the anaerobic/aerobic configuration was more flexible as it adapted quickly to the different loads and flows produced during the different phases through the year. Besides it allowed higher COD removals (98.5-99.2%) to be achieved and proved to permit a quicker re-start up after starvation periods. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the feasibility of the re-use of the winery wastewater to enhance the biological nutrient removal (BNR) process. In batch experiments it was observed that the addition of winery wastewater mainly enhanced the nitrogen removal process because of the high denitrification potential (DNP), of about 130 mg N/g COD, of the contained substrates. This value is very similar to that obtained by using pure organic substrates such as acetate. The addition of winery wastewater did not significantly affect either phosphorus or COD removal processes. Based on the experimental results obtained, the optimum dosage to remove each mg of N-NO3 was determined, being a value of 6.7 mg COD/mg N-NO3. Because of the good properties of the winery wastewater to enhance the nitrogen removal, the viability of its continuous addition in an activated sludge pilot-scale plant for BNR was studied. Dosing the winery wastewater to the pilot plant a significant increase in the nitrogen removal was detected, from 58 to 75%. The COD removal was slightly increased, from 89 to 95%, and the phosphorus removal remained constant. [ABSTRACT FROM AUTHOR]

In vineyards the presence of certain fungi may lead to the production of the mycotoxin ochratoxin A (OTA) and subsequent contamination of grapes and wine. Furthermore, winery wastewaters contaminated with OTA may represent an environmental hazard. Therefore, it is imperative to assess the fate of this mycotoxin in conventional wastewater treatment systems. The aim of the present work was to assess the biological degradation of OTA. Experimental work was carried out in batch experiments with initial OTA to biomass concentration ratios of 1.4µg mg-1, 7.4µg mg-1 and, 11.9 µg mg-1. The assays were inoculated with activated sludge biomass unadapted to the substance under examination. The proposed bioassay demonstrates that OTA concentrations up to 100 µgL-1 can be degraded by microbial activity in activated sludge. [ABSTRACT FROM AUTHOR]

The operational performance of anaerobic batch reactors treating winery wastewater (WW) combined with waste activated sludge (WAS) in different proportions was investigated under mesophilic conditions. In these experiments it was shown that for anaerobic digestion of WW alone, methane production rate was lower than the rates achieved when WW and WAS were treated together. When WW was mixed with WAS at a concentration of 50% WW resulted in the highest methane production rates. A simplified anaerobic model was used to determine the main kinetic parameters; maximum COD reduction rate (qDA) and maximum methane generation rate (kmax). The maximum values of qDA and kmax were 16.50 kgCODCOD-1 d-1 and 14.34 kgCOD kgCOD-1 d-1, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A lab-scale investigation was conducted to examine the effectiveness of a multi-fed upflow anaerobic filter process for the methane production from a rice winery effluent at ambient temperatures. The experiment was carried in two identical 3.0-l upflow filters, a single-fed reactor and a multi-fed reactor. The results showed that the multi-fed reactor, operated at the ambient temperatures of 19–27°C and influent chemical oxygen demand (COD) of 8.34–25.76g/l, could remove over 82% of COD even at an organic loading rate (OLR) of 37.68g-COD/ld and a short hydraulic retention time (HRT) of 8h. This reactor produced biogas with a methane yield of 0.30–0.35l-CH4/g-CODremoved. The multi-fed upflow anaerobic filter was proved to be more efficient than the single-fed reactor in terms of COD removal efficiency and stability against hydraulic loading shocks. A linear-regression model with influent COD concentration and HRT terms adequately described the multi-fed upflow anaerobic filter system for the treatment of rice winery wastewater at ambient temperatures. [Copyright &y& Elsevier]

Abstract: A membrane biological reactor (MBR), Zenon ZW-10, with a 220 L volume, was used during 120 days for treating two different wastewaters with different characteristics. During the first 50 operating days the unit was fed with an influent similar to the streams generated in wineries. From day 50 on, the MBR treated a wastewater generated in a tannery factory. The major differences between both wastewaters were the absence of both suspended solids and particulate chemical oxygen demand (COD) in the winery stream and the presence of these compounds in the wastewater from the tannery. Efficiency of the MBR was high: COD removal efficiency above 97% was obtained with winery wastewater, and about 86% during the period in which the tannery wastewater was used. COD concentration in the permeate of the unit varied between 60–80 mg COD/L during the whole experimental period, despite the differences in both wastewater characteristics and the operating conditions applied. Biomass concentration, in terms of volatile suspended solids (VSS), ranged between 0.5 and 15 g VSS/L. Apparent biomass yield was estimated at 0.14 g VSS/g COD and 0.16 g VSS/g COD for winery and tannery wastewater, respectively. A drop in the oxygen transfer efficiency was observed when the system operated with biomass concentrations above 8 g VSS/L. [Copyright &y& Elsevier]

Twenty-one samples of winery and distillery effluents were collected from different Spanish winery and distillery industries. Electrical conductivity, pH, redox potential, density, organic charge (chemical oxygen demand, biological oxygen demand, total, volatile and suspended solids, oxidisable organic C and polyphenols) and contents of plant nutrients and heavy metals were analysed. The aim of this work was to study the composition of these effluents and to find relationships which would make it possible to use easily determined parameters to estimate their composition. The winery wastewater (WW) and vinasse (V) showed an acidic pH, a high organic load and notable polyphenol, macronutrient, micronutrient and heavy metal contents. Some of these properties are not compatible with agricultural requirements; therefore, conditioning treatment of these liquid wastes is necessary to produce a safe, stable and easily manageable end product. Generally, in both effluent types, significant correlations were found between easily analysable parameters, such as suspended, volatile and total solids, pH, electrical conductivity, density and redox potential, and most of the parameters studied. The linear regression equations obtained permitted an immediate characterisation of the WW and V samples using these parameters. [ABSTRACT FROM AUTHOR]

Jet-loop type reactors developed in our group have been successfully used for biological treatment of winery and olive oil wastewaters. The objective of the present work was to study the influence of the reactor hydrodynamics, causing high shear stress applied on the nozzle and its influence on the composition of the microbial population. Winery and olive oil industry effluents were treated and analysed. Microbial consortia were enriched and selected under different bio-treatment conditions of the effluents. In the case of the winery wastewaters, the isolates identified belong to the genera of Pseudomonas and Bacillus. Saccharomyces cerevisiae was also present in the consortia but no filamentous fungi were detected. In the case of the olive oil wastewaters, Bacillus megaterium 2 was the predominant microorganism. It was not detected any type of fungi. [ABSTRACT FROM AUTHOR]

The treatment of winery wastewater was performed at full-scale applying a two-stage fixed bed biofilm reactor (FBBR) system for the discharge in the sewerage. The results of the first year of operation at the full-scale plant are presented. Values of removed organic loads and effluent concentrations were interpreted on the basis of the COD fractionation of influent wastewater assessed through respirometric tests. The average removal efficiency of total COD was 91%. It was not possible to reach an higher efficiency because of the unbiodegradable soluble fraction of COD (about 10% of total COD on average during the whole year), that cannot be removed by biological process or settling. Due to the high empty space offered by the plastic carriers, FBBRs did not require backwashing during the seasonal operationing period of the plant (September-March). In comparison with other treatment systems the FBBR configuration allows one to ensure a simple management, to obtain high efficiency also in the case of higher fluctuations of flow and loads and to guarantee a good settleability of the sludge, without bulking problems. [ABSTRACT FROM AUTHOR]

Jet-loop reactors (JLR) used as biological waste treatment processes introduce an additional selective pressure on the natural microbial flora of the incoming effluent. Several high-performing microbial inocula were tested for winery wastewater treatment and the microbial composition was analysed. A microbial consortium was enriched and selected for use with a new type of aerobic JLR. The reactor was operated continuously for more than 1 year using winery wastewaters collected in different seasons. Chemical oxygen demand (COD) removal efficiency was on average greater than 80%, with retention times of 0.8–1 day. Microbial populations were sampled for characterisation after 6 months and at the end of the study. Isolates were identified at genus and/or species level. Almost all isolates belonged to the genera Pseudomonas and Bacillus. Saccharomyces cerevisiae was also found but no filamentous fungi. These results show that a highly adapted population develops in JLRs treating winery effluents as compared to other bioreactors. Aerobic JLRs impose a stringent selective criterion on the composition of the microbial biomass. [ABSTRACT FROM AUTHOR]

Winery wastewaters are characterised by large seasonal fluctuations in volume and composition and are often discarded with little or no treatment. A rotating biological contactor (RBC) was used to investigate microorganisms associated with the biological treatment of winery wastewater. Extensive biofilms developed on the RBC discs and contained a number of yeast and bacterial species that displayed a dynamic population shift during the evaluation period. This suggested that the naturally occurring microorganisms were able to form a stable biofilm and also reduce the chemical oxygen demand (COD) of winery wastewater (on average 43% with a retention time of 1 h). One of the yeast isolates, MEA5, was able to reduce the COD of synthetic wastewater by 95% and 46% within 24 h under aerated and non-aerated conditions, respectively. The yeast isolates could therefore play an important role in the degradation of organic compounds under aerobic conditions, such as those associated with an RBC. [Copyright &y& Elsevier]

A jet-loop activated sludge reactor (JLR) of 15 dm3 working volume was used for the aerobic treatment of winery wastewater (WW). The reactor was operated continuously for more than 12 months using WW from different wineries and collected in different periods of the year with CODs that ranged between 0.8 and 12.8 kg m−3. Loading rates were from 0.4 to 5.9 kg-COD m−3 day−1 with hydraulic retention times that varied from 2.1 to 4.4 days. The system reacted well to sudden variations of loading: the COD removal efficiency was always higher than 90% with an organic load of the final effluents that ranged between 0.11 and 0.3 kg-COD m−3. After 185 days of continuous operation, the residential microbial population, of either the mixed liquor or the biofilm formed on the reactor''s inner wall, was studied and characterized at the genus level. Most isolates belong to the genus Pseudomonas and the yeast Saccharomyces cerevisiae. [Copyright &y& Elsevier]

Winery wastewater represents the largest waste stream in the wine industry. This deals with the mineralization of the organic matter present in winery wastewater using anodic oxidation and two types of anodes—namely, a boron-doped diamond electrode (BDD) and two mixed metal oxides (MMO), one with the nominal composition Ti/Ru0.3Ti0.7O2 and the other with Ti/Ir0.45Ta0.55O2. To conduct the study, the variability of different quality parameters for winery wastewater from the Chilean industry was measured during eight months. A composite sample was treated using anodic oxidation without the addition of supporting electrolyte, and the experiments were conducted at the natural pH of the industrial wastewater. The results show that this effluent has a high content of organic matter (up to 3025 ± 19 mg/L of total organic carbon (TOC)), which depends on the time of the year and the level of wine production. With MMO electrodes, TOC decreased by 2.52% on average after 540 min, which may be attributed to the presence of intermediate species that could not be mineralized. However, when using a BDD electrode, 85% mineralization was achieved due to the higher generation of hydroxyl radicals. The electrolyzed sample contained oxamic, acetic, and propionic acid as well as different ions such as sulfate, chloride, nitrate, and phosphate. These ions can contribute to the formation of different species such as active species of chlorine, persulfate, and perphosphate, which can improve the oxidative power of the system. [ABSTRACT FROM AUTHOR]

Despite many wineries being equipped with onsite wastewater treatment, winery wastewater (WWW) co-treatment at municipal wastewater treatment plants (WWTPs) remains a common practice in wine-making regions. The complex and highly variable nature of WWW can result in negative impacts on WWTP operations, highlighting a need for improved co-treatment methods. In this paper, the feasibility of using the Fenton-like process to pre-treat WWW to enhance co-treatment at municipal WWTPs is assessed. First-stage pre-treatment of the WWW, in the form of dilution and settling or aerobic biological treatment, is used prior to the Fenton-like process. A three-factor BBD experimental design is used to identify optimal reaction time and initial H2O2 and Fe3+ concentrations. Chemical oxygen demand (COD) and total organic carbon (TOC) removal rates are not able to accurately reflect the extent of reaction. Additional trials identified solubilization of particulate COD and TOC, as well as samples handling requirements prior to analysis, as factors affecting the apparent COD and TOC removal rates. Inert suspended solids (ISS) generated during the sample handling process are found to be the response variable best suited to quantifying the extent of the Fenton-like reaction. Maximum ISS generation is observed at initial H2O2 and Fe3+ concentrations of 4000 mg/L and 325 mg/L, however, results suggest that optimal concentrations exceed these values. The impact of adding pre-treated WWW, with and without Fenton-like treatment, to municipal WWTPs' primary clarifiers and aerobic bioreactors is also assessed via bench-scale trials. Challenges associated with co-treating WWW are found to remain despite the pre-treatment alternatives investigated, including negative impacts on simulated primary and secondary effluent quality. The Fenton-like AOP provides limited opportunity to optimize or enhance co-treatment at municipal WWTPs. [ABSTRACT FROM AUTHOR]

• Microalgae can grow in winery wastewater without any pre-treatment. • Mixotrophism promotes higher biomass accumulation and nutrient removals. • C. vulgaris is more resilient; efficient in removing COD and nitrogen (80 to 90%). • Difficult biodegradation of polyphenols. • Successful immobilization of TiO 2 ; no loss of photocatalytic activity in four cycles. This work intends to promote the growth of microalgae biomass with simultaneous remediation of an agro-industrial wastewater. Winery wastewater (WW) was used as growth media for the cyanobacteria Arthrospira maxima and the green microalgae Scenedesmus obliquus, Auxenochlorella protothecoides and Chlorella vulgaris , under mixotrophic and heterotrophic conditions. The latter species stands out under mixotrophic conditions, with removals of TOC and TN above 90%. Biomass production and pollutant removal were influenced by the initial WW concentration. Maximum removal values within 8 days of incubation were 92, 91, 49 and 40% for COD, TN, polyphenols and P-PO 4 , respectively, and 147.5 mg L−1 d−1 of biomass productivity. C. vulgaris biomass showed higher carotenoid content (maximum of 8.7 mg/g) when grown in WW, compared to autotrophic conditions (6.5 mg/g), making the bioremediation process more viable with the production of valuable by-products such as pigments. As the pollutant load removed by the microalgae does not allow reach the legal limits of release treated waters in natural water courses, a tertiary treatment process was applied. A post-treatment by photocatalysis in a UV LEDs photoreactor with TiO 2 -supported in Raschig rings was proposed for the removal of COD and polyphenols from a high loaded WW. The heterogeneous photocatalytic process was efficient in removing 80% of total polyphenols and 40% of COD, allowing the release of the treated water in superficial water courses since complies with the legal limits (COD below 150 mg L−1). [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimization of Stichococcus sp. biomass production growing immobilized in biofilms. • Seawater was used as the basis for the growth medium. • Sandblasted glass proved better for attachment compared to polyethylene and ceramic. • Two days nitrogen starvation towards the end of growth period boosted biomass yield. • Stichococcus grew optimally on winery wastewater solution after 2 days N starvation. Microalgae have been extensively used as animal feedstock and for the production of high-added value bioproducts, such as pigments and biodiesel. A promising strategy to simplify biomass recovery is by growing microalgae on flat biofilms, from where biomass may be easily harvested. Initially, the microalgae Stichococcus sp. was grown in photo-bioreactors, on seawater enriched with inorganic salts, on three different materials: ceramic tile, HD-polyethylene and sandblasted-glass, the latter of which exhibited the highest yield (up to 0.86 ± 0.02 mg cm−2 after 18 days cultivation period). Thereafter, the microalgae were grown on seawater enriched with winery-wastewater, applying nitrogen starvation during the last 2 days of cultivation, indicating biomass production of 1.00 ± 0.01 mg cm−2 (seawater plus organic carbon) to 1.30 ± 0.03 mg cm−2 (seawater plus organic carbon plus 2 days nitrogen starvation) to 1.43 ± 0.03 mg cm−2 (seawater plus inorganic carbon plus organic carbon plus 2 days nitrogen starvation). Trials on large scale photo-bioreactors confirmed the remediation potential of Stichococcus sp. for the treatment of winery-wastewater, while the organic carbon in wastewater boosted the yield of biomass production. Finally, the potential biomass yield of an industrial scale plant, treating winery-wastewater, was calculated to yield between 25−32 kg biomass (dry-basis) per 1000 m2 of shallow pond type reactor, per 18 days cultivation. [ABSTRACT FROM AUTHOR]

This research assessed a novel treatment process of winery wastewater, through the application of a chemical-based process aiming to decrease the high organic carbon content, which represents a difficulty for wastewater treatment plants and a public health problem. Firstly, a coagulation-flocculation-decantation process (CFD process) was optimized by a simplex lattice design. Afterwards, the efficiency of a UV-C/ferrous iron/ozone system was assessed for organic carbon removal in winery wastewater. This system was applied alone and in combination with the CFD process (as a pre- and post-treatment). The coagulation-flocculation-decantation process, with a mixture of 0.48 g/L potassium caseinate and 0.52 g/L bentonite at pH 4.0, achieved 98.3, 97.6, and 87.8% removals of turbidity, total suspended solids, and total polyphenols, respectively. For the ozonation process, the required pH and ferrous iron concentration (Fe 2+ ) were crucial variables in treatment optimization. With the application of the best operational conditions (pH = 4.0, [Fe 2+ ] = 1.0 mM), the UV-C/ferrous iron/ozone system achieved 63.2% total organic carbon (TOC) removal and an energy consumption of 1843 kWh∙m -3 ∙order -1 . The combination of CFD and ozonation processes increased the TOC removal to 66.1 and 65.5%, respectively, for the ozone/ferrous iron/UV-C/CFD and CFD/ozone/ferrous iron/UV-C systems. In addition, the germination index of several seeds was assessed and excellent values (>80%) were observed, which revealed the reduction in phytotoxicity. In conclusion, the combination of CFD and UV-C/ferrous iron/ozone processes is efficient for WW treatment.

A short review on the treatment of effluents from food processing industries by electrochemical oxidation (EO) was performed. Olive mill wastewater (OMW) and boron-doped diamond (BDD) are the most reported effluent and anode material, respectively. The addition of NaCl or Na2SO4 as supporting electrolytes is common in these studies, and their influence on the EO performance depends, among other things, on the anode material, since the electrolyte oxidation mechanism is different when active and non-active anode materials are utilized. A case-study on the application of a pilot plant, working in batch mode with recirculation, equipped with a BDD anode, to treat 4 L of OMW, slaughterhouse (SW) and winery (WW) wastewaters, with initial chemical oxygen demands (COD) of 20.5, 3.6 and 0.26 g L−1, respectively, is presented and discussed. In 16 h assays, 94% COD removal was achieved for OMW, and for SW and WW the Portuguese COD legal discharge limit of 150 mg L−1 was accomplished. Process efficiency decreased for lower organic load. NaCl addition increased COD removal in SW and WW, but presented an adverse effect for OMW COD removal, when compared to Na2SO4 addition. Nevertheless, lower specific energy consumptions were attained in chloride medium (48 Wh (g COD)−1). [ABSTRACT FROM AUTHOR]

The applicability and convenience of biohydrogen and poly-β-hydroxybutyrate production through single-stage photofermentation of winery wastewater is demonstrated in the present study. Experiments are conducted using a purple non-sulfur bacteria mixed consortium, subject to variable nutrient conditions, to analyze the effect of initial chemical oxygen demand and the available nitrogen source on the metabolic response. Results show that winery wastewater is a promising substrate for photofermentation processes, despite the presence of inhibiting compounds such as phenolics. Nonetheless, the initial chemical oxygen demand must be carefully controlled to maximize hydrogen production. Up to 468 mL L−1 of hydrogen and 203 mg L−1 of poly-β-hydroxybutyrate can be produced starting from an initial chemical oxygen demand of 1500 mg L−1. The used nitrogen source may direct substrate transformation through different metabolic pathways. Interestingly, the maximum production of both hydrogen and poly-β-hydroxybutyrate occurred when glutamate was used as the nitrogen source. • Photofermentation of winery wastewater allows contextual H 2 and PHB production. • Use of mixed PNSB cultures is beneficial to contrast the effect of toxic compounds. • Nitrogen source affects photofermentation development pathway. • N-Glutamate enhances both H 2 production and PHB concentration. • Inorganic nitrogen enhances PHB accumulation by PNSB. [ABSTRACT FROM AUTHOR]

The aim of this study was to estimate the carbon footprint (CFP) of constructed wetlands for winery wastewater treatment. In particular, a constructed wetland scenario was compared to the previous scenario (third-party management) and to an activated sludge system. CFP considered both indirect and direct greenhouse gas (GHG) emissions measured on-site. Moreover, an economic analysis of the considered scenarios was also addressed. The results showed that the constructed wetland scenario had the lowest CFP (1.2 kg CO 2 eq m water −3), while the third-party management was the worst scenario (52 kg CO 2 eq m water −3) followed by the activated sludge system (4.5 kg CO 2 eq m water −3). This was mainly due to the high GHG emissions generated by wastewater and sludge transportation as well as chemicals and electricity consumption in the third-party and activated sludge scenarios compared to the constructed wetlands. In terms of costs, the constructed wetland system was shown to be a low-cost technology which would reduce the capital, operation and maintenance costs associated with winery wastewater treatment up to 50% and 98%, respectively. Finally, constructed wetlands are low-cost and environmentally friendly technologies which constitute a sustainable alternative to conventional solutions for winery wastewater treatment. [ABSTRACT FROM AUTHOR]

In the Mediterranean region, climate change is likely to generate an increase in water demand and the deterioration of its quality. The adoption of precision viticulture and the best available techniques aiming at sustainable production, minimizing the impact on natural resources and reducing production costs, has therefore been a goal of winegrowers. In this work, the water footprint (WFP) in the wine sector was evaluated, from the vineyard to the bottle, through the implementation of a methodology based on field experiments and life cycle assessment (LCA) on two Portuguese case studies. Regarding direct water footprint, it ranged from 366 to 899 L/FU (0.75 L bottle), with green water being the most significant component, representing more than 50% of the overall water footprint. The approach used in the current study revealed that although more than 97.5% of the water footprint is associated with vineyard, the winery stage is responsible for more than 75% of the global warming potential indicator. A linear correlation between the carbon footprint and the indirect blue water footprint was also observed for both case studies. Climate change is expected to cause an earlier and prolonged water stress period, resulting in an increase of about 40% to 82% of blue WFP. [ABSTRACT FROM AUTHOR]

This paper reports a study on the performance of a multistage constructed wetland (CW) system adopted for winery wastewater and on the analysis of its suitability for irrigation reuse. The CW system treats about 3 m3·day−1 of wastewater produced by a small winery located in Sicily (insular Italy). Wastewater samples were collected at the CW inlet and outlet for physical–chemical and microbiological quality characterization. CW efficiency was evaluated on the basis of water quality improvement and of the achievement of Italian and EU irrigation reuse regulation limits. The CW system showed Chemical Oxygen Demand (COD) and Total Suspended Solids (TSS) mean removal rates of about 81% and 69%, and a maximum removal of about 99% (for both COD and TSS) occurred during grape harvest phase. The CW removal efficiencies for nutrients were 56% for TN and 38% for PO4-P, considering their low average concentrations at CW inlet. The CW system evidenced an effluent average quality compatible with the limits imposed by the Italian regulation and EU proposal regulation on the minimum requirement for water reuse. The CW vegetated area showed regular growth and vegetative development; phytotoxicity phenomena were not detected. The results of the study suggest the important role of CW systems in the treatment of winery wastewater and for their subsequent reuse in agriculture. [ABSTRACT FROM AUTHOR]

• Heterogeneous catalysts based on natural materials. • Influence of different metallic pillared clays on the photocatalysis. • Improvement of catalyst textural properties resulted by the pillaring process. • Low leaching levels confirms efficient catalyst immobilization. • Influence of different operational conditions on the TOC removal. The present research assessed, for the first time, the application of natural pillared clays (PILCs: Al-Cu-ST and Al-Fe-ST) as heterogeneous photocatalysts for the H 2 O 2 -assisted treatment of a real winery wastewater (WW), which is characterized by high loads of recalcitrant polyphenolic compounds. The heterogeneous photocatalysts were characterized by XRD, FTIR, N 2 adsorption isotherms and SEM-EDX, and successful immobilization of the active phase on natural smectite (Ca-ST) was confirmed. The influence of various parameters, such as initial pH, H 2 O 2 concentration and catalyst dosage, on catalyst activity and on the metal leaching from the heterogeneous catalysts were investigated. The results demonstrated that Al-Cu-ST exhibits higher activity than Al-Fe-ST, however, lower stability along 3 consecutive cycling processes (pH = 3.0; S:L = 3.00 g/L, [H 2 O 2 ] 0 = 98 mM). Accordingly, the TOC removals varied between 79.3% and 75.2%, and between 67.1% and 57.9%, using Al-Cu-ST and Al-Fe-ST, respectively, from the 1st to the 3rd cycle. The metal leaching concentrations were in both cases lower than the legal limits imposed, along the cycling processes. A lumped kinetic model based on the Fermi's equation was successfully applied in order to describe the kinetics of the photo-oxidation processes. Accordingly, the higher rate process was achieved at pH 3.00, using a H 2 O 2 concentration corresponding to 98 mM, and a Al-Cu-ST dosage of 3.00 g/L (k TOC = 3.76 × 10−2 min−1). [ABSTRACT FROM AUTHOR]

Concentration polarization is intrinsically associated with the selective character of membranes and often means flux decline and which causes a subsequent decrease of ultrafiltration and nanofiltration performance. More important is the fact that it acts as a precursor of membrane fouling and creates severe fouling problems in the longer times range. The quantification of its dependence on the operating parameters of cross-flow velocities and transmembrane pressures makes recourse to the film theory to introduce mass-transfer coefficients that generally are calculated by dimensionless correlations of the Sherwood number as a function of the Reynolds and Schmidt numbers. In the present work, the mass-transfer coefficients are obtained through the fitting of experimental results by the pressure variation method. The ultrafiltration/nanofiltration of the winery wastewaters from the racking operation is carried out with the membranes ETNA 01PP (Alfa Laval) and NF 270 (Dow Filmtec) under a wide range of cross-flow velocities and transmembrane pressures up to 15 bar. [ABSTRACT FROM AUTHOR]