In a world where the water crisis threatens to limit food production and the stability of ecosystems, the olive industry faces a dual challenge: ensuring process quality while reducing pressure on water resources. In Mediterranean regions with high olive specialization, water scarcity is intensified by increasingly extreme climate cycles, while thousands of cubic meters of “liquid brine” , a residual brine rich in organic compounds, are discarded every year without recovering their water potential or mineral value. This is not just a loss of resource; it is a loss of opportunity.
This project is located in [insert municipality and country], at the epicenter of one of Europe’s most productive olive-growing basins. Its strategic objective is clear: to transform a problematic effluent into a safe, traceable resource to be reintegrated into the industrial process or allocated to secondary uses, reducing freshwater abstraction and mitigating associated environmental impacts. Through a modular system combining physical-chemical treatment and chlorine-free disinfection, the proposed solution recovers more than 70% of the treated volume at certified quality, removing salts and organic matter to levels compliant with reuse parameters.
The rationale for this project lies in the urgency to transition toward a Water Positive model, where every cubic meter extracted is offset or exceeded by regenerated volumes. It fully meets the principles of additionality, by treating a stream that is currently not reused, intentionality, by embedding reuse into the operational strategy, and traceability, through digital monitoring of flows and water quality under VWBA/WQBA methodology. The stakeholders include the olive plant operator, the treatment technology provider, the project structurer, and the independent verification entity that will certify the water and quality benefits.
In a global market increasingly demanding in terms of sustainability and traceability, this intervention not only solves a technical problem: it sets a new circular production standard for an iconic sector of the Mediterranean diet, with the potential to be replicated in hundreds of similar plants.
The table olive industry generates large annual volumes of “liquid brine”, a mixture of brine and organic compounds, that, without specific treatment, cannot be reused or discharged without environmental risk. This results in additional freshwater consumption for replenishment, costly effluent management, and a high water footprint in areas where the resource is scarce. Causes include the historical absence of recovery technologies specific to this stream, stricter environmental regulations, and growing social and commercial pressure to reduce water footprints.
The technical opportunity lies in implementing a tailor-made treatment that combines filtration, desalination, and advanced disinfection stages to produce regenerated water suitable for facility cleaning, controlled irrigation, or reintegration into non-critical processes. With an expected treatment volume of [insert m³/year], the system will recover more than 70% of the water contained in the effluent, reducing freshwater abstraction by the same proportion and lowering pollutant loads by over 90%. Immediate impacts will include significant operational cost savings and the elimination of saline discharges; medium-term benefits will be improved water resilience for the plant; and long-term outcomes will be the consolidation of a circular model replicable across the industry.
The proposed model is scalable and adaptable to different production capacities, with physical traceability through flow and quality meters, and digital traceability through a georeferenced record system validated by third parties. Agro-industrial companies with ESG goals and commitments to SDG 6 (Clean Water and Sanitation), SDG 12 (Responsible Consumption and Production), and SDG 13 (Climate Action) will find in this project a tangible way to meet targets, reduce regulatory risks, and strengthen their reputation.
Acting now means shifting from reactive waste management to active resource valorization, positioning the company as a benchmark in water efficiency and sustainability within a traditional sector that demands innovation.
The implemented technology allows for the comprehensive transformation of the saline effluent through a series of synergistic processes that effectively remove contaminants and recover water in optimal conditions for industrial reuse.
Initially, the mother liquor is captured directly from its points of generation in the plant and routed to a physical pretreatment stage, where suspended solids and coarse sediments are removed via screening and multilayer filtration.
Next, the stream undergoes an advanced oxidation process (AOP), which may combine technologies such as cavitation, ozonation, or activated peroxides to break down complex molecular structures and degrade persistent organic compounds. This treatment significantly reduces COD, polyphenols, and other recalcitrant elements. In parallel, efficient disinfection is carried out using non-chlorine methods (such as UV radiation or cold plasma), ensuring the elimination of microorganisms without generating harmful by-products.
The purified water is stored in an intermediate tank equipped with automated quality monitoring, and subsequently recirculated to the olive washing lines, preparation of new brines, or other auxiliary uses within the plant. This setup reduces freshwater intake by more than 80% and eliminates the need for external discharge, aligning with circular economy principles and environmental compliance.
SDG 6 – Clean Water and Sanitation: The project supports this goal by reducing freshwater withdrawal through a recirculation system and by properly treating a high-load effluent, preventing its discharge and improving water quality.
SDG 9 – Industry, Innovation and Infrastructure: It promotes the implementation of clean and innovative technologies that optimize industrial processes for water treatment and reuse.
SDG 12 – Responsible Consumption and Production: It fosters the transition toward circular models by converting mother liquor into a reusable water resource within the production process.
SDG 13 – Climate Action: It strengthens the climate resilience of the industry by reducing dependence on vulnerable water sources in a context of increasing water stress due to climate change.
SDG 17 – Partnerships for the Goals: It enables effective collaboration among different actors in the water ecosystem (plant operator, technology providers, authorities, and certifiers) to advance integrated sustainability solutions.
The treatment system comprises a sequence of interconnected modules designed for autonomous, continuous operation, ensuring both operational efficiency and process traceability.
Mother liquor is captured directly from the curing and preservation process through bypass pipelines equipped with automated valves and flow sensors. In the initial stage, the effluent passes through screening and multilayer physical filtration systems to retain suspended solids, organic particles, and olive residues.
Subsequently, the water is fed into an advanced oxidation reactor (AOP) where technologies such as in-line ozonation, acoustic cavitation, or hydroxyl radical treatment via cold plasma are applied. This stage breaks down recalcitrant organic compounds like polyphenols and significantly reduces COD.
The treated water then passes through a non-chlorinated disinfection unit using high-intensity ultraviolet radiation or electrochemical oxidation processes. This ensures pathogen removal without generating health-harming by-products or altering the physico-chemical quality of the water. Finally, the regenerated water is directed to an intermediate accumulation tank equipped with integrated quality sensors, from which it is recirculated to the washing lines, brine formulation, or equipment cleaning processes.
Monitoring Plan: Monitoring is conducted in real-time via an IoT sensor network measuring key parameters such as COD, electrical conductivity, turbidity, pH, and temperature. Data is transmitted to a digital platform that enables trend visualization, anomaly detection, and automated alert generation. A satellite remote sensing system is also integrated to assess correlations between water use, liquid waste generation, and seasonal variations in production. Result validation is complemented by monthly analyses conducted in an external ISO 17025-accredited laboratory.
Key Partnerships and Implementing Actors: he project involves several critical stakeholders. The company operating the plant is responsible for daily system management and operations. The technology provider supplies engineering, installation, and technical support for the modular system. The regional environmental authority oversees regulatory compliance, especially regarding discharges and water resource use.
This project aims to comprehensively transform water management at an olive processing plant in southern Spain by recovering and reusing the mother liquor produced during fermentation. It addresses two core challenges: pressure on the Guadalhorce River basin aquifers and the need to treat a highly saline, organic-loaded industrial effluent.
Mother liquor is a complex by-product with properties that hinder its treatment through traditional means: high salt concentration, recalcitrant organic compounds (phenols, proteins, polysaccharides), microbial presence, and low biodegradability. Its management has historically entailed high logistical, environmental, and regulatory costs. Simultaneously, the plant consumes significant volumes of potable or well water for washing and conditioning olives, in a region increasingly affected by water scarcity.
The proposed technological solution is a modular system combining physical pretreatment, advanced oxidation, and chemical-free disinfection, followed by automated recirculation. The design enables continuous operation, adaptation to fluctuating effluent loads, and achievement of water quality standards suitable for internal reuse. This setup reduces freshwater consumption by over 80%, eliminates discharges, and promotes a circular economy model replicable in other agro-industrial contexts.
The project stands as a scalable and replicable innovation for the agri-food sector in southern Europe, where water management is a strategic environmental and productivity factor. Its holistic approach not only ensures regulatory compliance but also anticipates emerging corporate water sustainability reporting frameworks.
