Constructed wetlands for winery wastewater treatment: a comparative Life Cycle Assessment

A Life Cycle Assessment was carried out in order to assess the environmental performance of constructed wetland systems for winery wastewater treatment. In particular, six scenarios which included the most common winery wastewater treatment and management options in South-Western Europe, namely third-party management and activated sludge systems, were compared. Results showed that the constructed wetland scenarios were the most environmentally friendly alternatives, while the third-party management was the worst scenario followed by the activated sludge systems. Specifically, the potential environmental impacts of the constructed wetlands scenarios were 1.5–180 and 1–10 times lower compared to those generated by the third-party and activated sludge scenarios, respectively. Thus, under the considered circumstances, constructed wetlands showed to be an environmentally friendly technology which helps reducing environmental impacts associated with winery wastewater treatment by treating winery waste on-site with low energy and chemicals consumption.Peer ReviewedPostprint (author's final draft

Análisis del ciclo de vida de humedales construidos para el tratamiento de aguas residuales de bodegas

Wine industry generates large volumes of wastewater originating from various processes and operations carried out during wine production. Spain is considered one of the world's largest wine-producing countries. Nevertheless, most of wineries still lack of a proper wastewater treatment system. Constructed wetland systems constitute an alternative to conventional systems due to their low cost, low energy requirement and easy operation and maintenance. The aim of this work is to assess the environmental impacts of constructed wetlands for winery wastewater treatment

Constructed wetlands for winery wastewater treatment: Sustainability and circular economy in the wine sector

The wine industry generates large volumes of wastewater originating from various processes and operations carried out during wine production. Winery wastewater (WWW) is characterized by highly variable flows and loadings. Indeed, more than half of the annual wastewater flow and load is produced during the vintage season, when grape is harvested and grape juice is handled and managed. Spain is one of the world's largest wine-producing countries. Nevertheless, in most of the Spanish wineries wastewater is still not properly treated or managed. In this context, constructed wetlands (CWs) constitute a suitable alternative to conventional systems (e.g. activated sludge systems, membrane bioreactors) for WWW treatment due to their low cost, low energy requirement, easy operation and maintenance and their integration into the landscape. From a technical point of view, full-scale applications of CWs have demonstrated to reduce more than 90% of the organic pollutants and solids from WWW producing suitable water for multiple reuse purposes such as irrigation. Moreover, primary treatments of CWs can produce sludge which can be stabilised in sludge treatment wetlands (STWs) producing biofertilizers and soil conditioners. The production of reclaimed water and biofertilizers from WWW can promote the circular economy in the wine sector increasing their sustainability. Although CWs application in the wine sector has been widely proved from a technical point of view, there are still no studies which assess and quantify their environmental benefits in the context of circular economy. This PhD Thesis aims to assess and quantify the environmental benefits of CWs for WWW treatment compared with existing and conventional solutions. To address this objective, a life cycle assessment (LCA), greenhouse gas (GHG) emissions measurements and a carbon footprint (CFP) evaluation were carried out comparing CW systems with conventional technologies and other existing alternatives (i.e. activated sludge system and third-party management). This research has been carried out in the frame of the WETWINE project (http://wetwine.eu/) which aimed to promote environmentally friendly and innovative solutions to treat effluents produced by wine industries in the South-West of Europe. Thus, this research was based on the study of different full-scale systems implemented in wineries located in Galicia (Spain), Portugal and Southern France. In particular, a CW system has been designed and implemented in a winery located in Galicia, in which experimental activities have been carried out. The results of the LCA showed that the environmental impacts of CWs were between 1.5 and 180 times lower than the third-party management alternative and between 1 and 10 times lower than the activated sludge system. GHG emissions (carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4)) were monitored in a CW and an activated sludge systems using an on-site Fourier transform infrared spectroscopy (FTIR) gas analyser. Results highlighted that surface emission rates from the CW system were lower than those released by the activated sludge system. Furthermore, seasonally, daily and instantaneous variability in emissions as well as spatial variability were recorded and reported. The CFP of the CW system was up to 42 times lower in comparison with the third-party management and up to 4 times lower than the activated sludge system. Finally, an economic assessment was conducted. CWs can reduce winery costs associated with WWW treatment up to 50% for the construction and up to 98% for the operation and maintenance. Finally, this PhD Thesis assessed and quantified, for the first time, the environmental benefits of CWs for WWW treatment. CWs were proven to be a sustainable solution for WWW and sludge treatment, since they are an environmentally friendly and cost-effective alternative which can promote the circular economy in wineries enabling sludge and water treatment and reuse on-site.La indústria del vi genera grans volums d’aigües residuals procedents de diversos processos i operacions realitzats durant la producció del vi. Les aigües residuals de celler (ARC) es caracteritzen per tenir uns cabals i càrregues molt variables. De fet, més de la meitat del cabal i càrrega produïts durant l’any es concentren durant l’època de verema, quan es recull el raïm i es produeix el suc de raïm. Espanya és considerada un dels països amb major producció de vi. No obstant això, a la majoria dels cellers Espanyols les aigües residuals encara no són tractades o gestionades adequadament. En aquest context, els aiguamolls construïts (AC) són una alternativa als sistemes convencionals (p. ex. Sistema de fangs activats, bioreactors de membrana) per al tractament de les ARC ja que tenen un baix cost, baix requeriment d’energia, fàcil operació i manteniment i una bona integració al paisatge. Des d’un punt de vista tècnic, s’ha demostrat que les aplicacions d’AC a escala real redueixen més d’un 90% dels contaminats orgànics i dels sòlids de les ARC produint aigua apta per múltiples usos de reutilització com el reg. A més, el tractament primari dels AC pot produir fangs que poden ser estabilitzats a aiguamolls de tractament de fangs per a produir biofertilitzants i adobs orgànics. La producció d’aigua regenerada i biofertilitzants a partir de les ARC pot promoure l’economia circular al sector vitivinícola augmentant la seva sostenibilitat. Tot i que l’aplicació dels AC al sector vitivinícola ha estat àmpliament provada des d’un punt de vista tècnic, encara no existeixen estudis que avaluïn i quantifiquin els seus beneficis ambientals en el context de l’economia circular. Aquesta tesi doctoral té com a objectiu avaluar i quantificar els beneficis ambientals dels AC per al tractament de les ARC en comparació amb les solucions existents i convencionals. Per abordar aquest objectiu, s’ha dut a terme una avaluació del cicle de vida (ACV), mesures de gasos d’efecte hivernacle (GEH) i una avaluació de la petjada de carboni comparant els sistemes d’AC amb tecnologies convencionals i altres alternatives existents (és a dir, el sistema de fangs activats i la gestió per tercers). Aquesta investigació s’ha realitzat en el marc del projecte WETWINE (http://wetwine.eu/) que va tenir com a objectiu promoure solucions innovadores i respectuoses amb el medi ambient per al tractament d’efluents produïts per la industria vitivinícola al sud-oest d’Europa. Per això, aquesta investigació s’ha basat en diferents sistemes a escala real implementats a bodegues ubicades a Galícia (Espanya), Portugal i sud de França. En particular, s’ha dissenyat i implementat un sistema d’AC a un celler situat a Galícia, on s’ha dut a terme activitats experimentals. Els resultats de l'ACV van mostrar que els impactes ambientals dels AC eren entre 1,5 i 180 vegades inferior que la gestió per tercers i entre 1 i 10 vegades inferior que el sistema de fangs activats. Les emissions de GEH (és a dir, diòxid de carboni (CO2), òxid nitrós (N2O) i metà (CH4)) es van monitoritzar en un sistema de fangs activats i AC utilitzant un analitzador de gasos d'espectroscòpia infraroja per transformada de Fourier (FTIR) in situ. Els resultats van destacar que les taxes d'emissió superficial del sistema d'AC van ser més baixes que les generades pel sistema de fangs activats. A més, es va registrar i documentar variabilitat estacional, diària i instantània a les emissions, així com variabilitat espacial. La petjada de carboni del sistema d'AC era fins a 42 vegades inferior en comparació amb la gestió per tercers i fins a 4 vegades inferior al sistema de fangs activats. Finalment, aquesta tesi ha avaluat i quantificat, per primera vegada, els beneficis ambientals dels AC per al tractament d’ARC. S’ha demostrat que són una solució sostenible per al tractament d’aigües residuals i fangs a les bodegues ja que són una alternativa respectuosa amb el medi ambient i rentable econòmicament que pot promoure l’economia circular permetent el tractament i reutilització de fangs i aigües in situ. Els resultats de la investigació d’aquesta tesi poden ajudar a impulsar la implementació dels AC al sector vitivinícola, així com a difondre els seus beneficis ambientals per guanyar més acceptació social.Postprint (published version

Análisis del ciclo de vida de humedales construidos para el tratamiento de aguas residuales de bodegas

Wine industry generates large volumes of wastewater originating from various processes and operations carried out during wine production. Spain is considered one of the world's largest wine-producing countries. Nevertheless, most of wineries still lack of a proper wastewater treatment system. Constructed wetland systems constitute an alternative to conventional systems due to their low cost, low energy requirement and easy operation and maintenance. The aim of this work is to assess the environmental impacts of constructed wetlands for winery wastewater treatment

Análisis del ciclo de vida de humedales construidos para el tratamiento de aguas residuales de bodegas

Wine industry generates large volumes of wastewater originating from various processes and operations carried out during wine production. Spain is considered one of the world's largest wine-producing countries. Nevertheless, most of wineries still lack of a proper wastewater treatment system. Constructed wetland systems constitute an alternative to conventional systems due to their low cost, low energy requirement and easy operation and maintenance. The aim of this work is to assess the environmental impacts of constructed wetlands for winery wastewater treatment

Life Cycle Assessment of wastewater treatment systems for small communities: activated sludge, constructed wetlands and high rate algal ponds

The aim of this study was to assess the environmental impact of three alternatives for wastewater treatment in small communities. To this end, a Life Cycle Assessment (LCA) was carried out comparing a conventional wastewater treatment plant (i.e. activated sludge system) with two nature-based technologies (i.e. hybrid constructed wetland and high rate algal pond systems). Moreover, an economic evaluation was also addressed. All systems served a population equivalent of 1500 p.e. The functional unit was 1 m3 of water. System boundaries comprised input and output flows of material and energy resources for system construction and operation. The LCA was performed with the software SimaPro® 8, using the ReCiPe midpoint method. The results showed that the nature-based solutions were the most environmentally friendly alternatives, while the conventional wastewater treatment plant presented the worst results due to the high electricity and chemicals consumption. Specifically, the potential environmental impact of the conventional wastewater treatment plant was between 2 and 5 times higher than that generated by the nature-based systems depending on the impact category. Even though constructed wetland and high rate algal pond systems presented similar results in terms of environmental impact, the latter showed to be the less expensive alternative. Nevertheless, the constructed wetland system should be preferred when land occupation is of major concern, since it has a smaller footprint compared to the high rate algal pond alternative.Peer Reviewe

Life Cycle Assessment of wastewater treatment systems for small communities: activated sludge, constructed wetlands and high rate algal ponds

The aim of this study was to assess the environmental impact of three alternatives for wastewater treatment in small communities. To this end, a Life Cycle Assessment (LCA) was carried out comparing a conventional wastewater treatment plant (i.e. activated sludge system) with two nature-based technologies (i.e. hybrid constructed wetland and high rate algal pond systems). Moreover, an economic evaluation was also addressed. All systems served a population equivalent of 1500 p.e. The functional unit was 1 m3 of water. System boundaries comprised input and output flows of material and energy resources for system construction and operation. The LCA was performed with the software SimaPro® 8, using the ReCiPe midpoint method. The results showed that the nature-based solutions were the most environmentally friendly alternatives, while the conventional wastewater treatment plant presented the worst results due to the high electricity and chemicals consumption. Specifically, the potential environmental impact of the conventional wastewater treatment plant was between 2 and 5 times higher than that generated by the nature-based systems depending on the impact category. Even though constructed wetland and high rate algal pond systems presented similar results in terms of environmental impact, the latter showed to be the less expensive alternative. Nevertheless, the constructed wetland system should be preferred when land occupation is of major concern, since it has a smaller footprint compared to the high rate algal pond alternative.Peer Reviewe

Carbon footprint of constructed wetlands for winery wastewater treatment

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 CO2eq mwater-3), while the third-party management was the worst scenario (52 kg CO2eq mwater-3) followed by the activated sludge system (4.5 kg CO2eq mwater-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.This research was funded by the European Regional Development Fund (Interreg V-B SUDOE programme, WETWINE SOE1/P5/E0300). Laura Flores is grateful to the Ministry of Education and Culture (MECD) (Spain) for the FPU16/01491 scholarship. Joan García, Marianna Garfí and Laura Flores are grateful to the Government of Catalonia (Consolidated Research Group 2017 SGR 1029). Marianna Garfí acknowledges the Spanish Ministry of Economy and Competitiveness (RYC-2016-20059). The authors are grateful for the support provided by the WETWINE consortium and the wineries involved in this study.Peer ReviewedPostprint (author's final draft

Promotion of full-scale constructed wetlands in the wine sector: comparison of greenhouse gas emissions with activated sludge systems

The aim of this study was to quantify and compare greenhouse gas (GHG) (i.e. carbon dioxide (CO2), nitrousoxide (N2O) and methane (CH4)) emissions from two full-scale winery wastewater and sludge treatment sys-tems (i.e. constructed wetlands (CWs) and activated sludge system) located in Galicia (Spain). GHG fluxeswere measured using the static chamber method in combination with an on-site Fourier transform infrared spectroscopy (FTIR) gas analyser in the CWs system. These on-site innovative techniques proved to be very accurateand reliable. In the activated sludge treatment systems, thefloating chamber method in combination with the FTIR gas analyser was used. Measurements were carried out during the vintage season, when winery wastewaterhas the highestflow and loads, and the rest of the year. Emission rates of CO2, N2O and CH4 in the CWs units(i.e. vertical flow, horizontal subsurface flow and sludge treatment wetlands) ranged from 1.35E+02 to 7.54E+04, 1.70E-01 to 3.09E+01 and-3.05E+01 to 1.79E+03 mg m-2day-1, respectively. In the case ofthe activated sludge units (i.e. reactor, secondary settler and sludge storage tank) emission rates CO2, N2O and CH4 ranged from 1.56E+04 to 1.43E+05, 1.13E+01 to 4.75E+01 and 2.52E+01 to 1.01E+03 mg m-2 day-1, respectively. Seasonally, daily and instantaneous variability in emissions as well as spatial variability was found. Comparing CWs with the activated sludge system, surface emission rates were lower in the CWs system in both seasons considered. Results highlighted that CWs are suitable technologies that can help to reduce GHG emis-sions associated with winery wastewater treatment.This research was funded by the European Regional Development Fund (Interreg V-B SUDOE programme, WETWINE SOE1/P5/E0300) (http://wetwine.eu/). Laura Flores is grateful to the Ministry of Education and Culture (MECD) (Spain) for the FPU16/01491 scholarship. Joan García, Marianna Garfí and Laura Flores are grateful to the Government of Catalonia (Consolidated Research Group 2017 SGR 1029). Marianna Garfí is grateful to the Spanish Ministry of Economy and Competitiveness (RYC-2016-20059). The authors are grateful for the support provided by the WETWINE consortium and the wineries involved in this study. The results shown in this paper were presented in the 2019 WETPOL Conference (Aarhus, Denmark) under the oral presentation: “Constructed wetlands release less greenhouse gas emissions than activated sludge: a key point for their implementation in the wine sector” by Laura Flores who was awarded with the First Prize in the Society of Wetland Scientists (SWS) Europe Chapter Oral Presentation Competition.Peer ReviewedObjectius de Desenvolupament Sostenible::6 - Aigua Neta i SanejamentObjectius de Desenvolupament Sostenible::6 - Aigua Neta i Sanejament::6.3 - Per a 2030, millorar la qualitat de l’aigua mitjançant la reducció de la contaminació, l’eliminació dels abocaments i la reducció al mínim de la descàrrega de materials i productes químics perillosos, la reducció a la meitat del percentatge d’aigües residuals sense tractar, i un augment substancial a escala mundial del reciclat i de la reutilització en condicions de seguretatPostprint (author's final draft