Water use has been rising globally at a rate of 1 % a year for several decades, and this trend is not likely to change. In Europe, industry is one of the biggest users, responsible for more than 30 % of water consumption. Freshwater is needed to support many industrial practices, and often the wastewater generated is contaminated, posing a threat to the environment. With case studies in Germany, Greece and Spain, the EU-funded intelWATT project addresses both high consumption levels and water pollution concerns with a suite of technological advances applicable to diverse industries.
Targeting energy production, mining and electroplating
The project targets three industries with significant water demands. Energy production, with a reliance on cooling towers, uses copious amounts of fresh water. Industrial brines generated from mining have untapped resource potential. And while electroplating has a more modest water usage than some industries, the metal-laden wastewaters present an environmental hazard. According to project coordinator Andreas Sapalidis from the National Centre for Scientific Research "Demokritos" (Greece): “The main objective of the intelWATT project is to validate, at TRL8, innovative and intelligent water treatment technologies combining freshwater preservation, resource recovery and energy conversion based on the circular economy concept.” The evaporating water in power plant cooling towers leaves behind minerals. Freshwater is used to remove the accretions in a process called cooling tower blowdown (CTBD). By recycling CTBD water in the first case study, intelWATT aims to reduce water consumption by 99 %. In the second case study, which is focused on industrial mines, the project aims to recover water and valorise the brine stream. The pilot demonstrates harvesting salinity gradient power and recovering deionised water through membrane distillation. The third case demonstrates the recovery of valuable electrolytes and water preservation in an electroplating facility. The aim is to recover up to 85+ % of chromium and copper and 50 % of nickel while preserving 95+ % of fresh water in a TRL 8 pilot unit.
Smart water separation technologies
At the heart of intelWATT solutions are novel wastewater treatment processes and the application of AI mechanisms, Sapalidis says: “The intelWATT project has achieved considerable advances in a broad range of disciplines, specifically regarding materials, smart sensors, modelling, processes and pilot units.” Among the materials designed by intelWATT are several types of membranes used for filtration, distillation, reverse osmosis and electrodialysis. This collection of materials includes graphene-based membranes, an emerging tool in separation processes. The development of smart sensors supports communication and secure data transmission. Other smart technologies include machine learning algorithms that improve predictive modelling and smart monitoring that is expected to yield a 30 % reduction in energy demands. The project’s advances in water treatment processes, such as reverse osmosis, reverse electrodialysis and membrane crystallisation enable energy harvesting and material recovery in wastewater treatment. The creation of AI-based pilot studies enabled intelWATT to develop multiple tools and processes for water management. The fact that the case studies are at a high technological readiness level is encouraging, as it indicates the possibility of rapid adoption by industry stakeholders and the advancement of a Europe-wide circular economy. The project’s contributions to water preservation and resource recovery are significant and will help Europe safeguard water – one of society’s most precious resources.
