LIFE SOLIEVA. Circular economy applied to the treatment of table olives brines based on solar evaporation

The main goal of the project “Circular economy applied to the treatment of table olives brines based on solar evaporation”, financed by the LIFE program of the European Union with the acronym LIFE SOLIEVA (LIFE17 ENV/ES/000273), is to demonstrate the technical, environmental and economic feasibility of the technology based on membrane, concentrator vacuum and spray dryer (OCR) and advanced solar evaporation (ASE) to face the environmental challenges of the table olive sector (TO) in the treatment of the table olive processing wastewater (TOPWW) and update the environmental legislation related to use of water.

The project is coordinated by EURECAT (Spain) and other partners are: CTNC (Spain), CITOLIVA (Spain), TYPSA (Spain), OLEAND (Spain) and PEMETE (Greece). It is a balanced consortium of companies to transfer project results to European food sector, with a budget of 2,122,480 euros. Currently TOPWW, composed by NaOH, salt and organic matter is accumulated in evaporation ponds entailing a loss of water and resources (NaOH, salt and organic matter) land occupation and high risk of pollution due to spills or overflows of the ponds. The proposed solution is based on resource recovery and zero liquid discharge (ZLD) schemes reducing the land occupation of ponds raising the natural evaporation rate and moving forward to circular economy systems. As indicated, the wastewater from the processing of table olives contains a high content of organic matter and salts from the industrial process itself, which make its management difficult. Specifically, the presence of phenolic compounds, such as hydroxytyrosol (2- (3,4-dihydroxyphenyl) ethanol), represents one of the main problems for their treatment, mainly because they are hardly biodegradable and, secondly, because of their important activity antimicrobial, which reduces the efficiency of biological processes in wastewater treatment plants. And to this should be added the high consumption of water, which generates large volumes of discharge. On the other hand, recovering valuable polyphenols to be used in the food and health industry opens an opportunity to create new business models following the principles of industrial symbiosis. CTNC collaborates in the polyphenol recovery stage mainly. The project started in 2018 and TOPWW have been characterized, concentrated, atomized and purified, trying to optimize a process of interest to the sector. One of the results achieved is that the waters from the treatment of the Manzanilla variety are those with a higher content of polyphenols, being able to recover and purify a higher content of hydroxytyrosol for its application in the development of functional foods. Currently, CTNC staff continue to work on the project, which will end in late 2021. In the coming months, new foods will be developed with the extracts obtained, where the partner CITOLIVA will also participate. More information at www.lifesolieva.eu and @LifeSolieva.