Modelling and experimental investigation of a novel ion exchange membrane crystallizer for magnesium recovery

Techno-economic analysis of a novel hybrid system for the valorisation of SWRO brines in a minor Sicilian island

In small remote islands, freshwater scarcity is an issue to which several viable solutions have already been found employing constantly evolving desalination technologies. The several RO plants in the Canary and minor Sicilian Islands are just an example . However, the beneficial application of seawater desalination is accompanied by a problematic matter: the production of high salinity brines. Not only do they compromise the aquatic ecosystem but their treatment in order to respect environmental regulations is costly too. Worth noting how these so-called “wastewater streams” present a high concentration of valuable raw materials, such as magnesium and calcium or sodium chloride, that are e…

ION EXCHANGE MEMBRANE CRYSTALLIZER FOR MAGNESIUM RECOVERY FROM SEAWATER AND INDUSTRIAL BRINE

The treatment and valorisation of waste brines deriving from industrial processes raised in the last years a strong interest in order to promote the whole process sustainability both in terms of minimisation of environmental impacts and raw materials recovery within a circular economy approach. With this respect, magnesium recovery from brines can be an interesting and practical example. In this work, a novel ion exchange membrane crystallizer (CrIEM1) is presented. In a CrIEM reactor, the presence of an Anion Exchange Membrane, separating a brine and an alkaline solutions, allows the passage of hydroxyl ions from the alkaline to the brine compartment, where crystallization of magnesium hyd…

Modelling of an innovative membrane crystallizer for the production of magnesium hydroxide from waste brine

Background The discharge of industrial waste brines into natural water bodies has gained large interest in recent years, both for its possible environmental impact, but also for the high potential of raw materials recovery contained in brines, pushing towards a circular economy approach. Among such raw materials, magnesium is often abundant and has been defined as aCritical Raw Material by EU [1]. Within this framework, a Crystallizer with Ion Exchange Membrane (CrIEM) has been proposed as an innovative process to recover magnesium from waste brines exploiting low-cost alkaline reactants. In the present work, a novel mathematical model of the CrIEM process is proposed providing a useful too…