Development of a pilot plant for the recovery of magnesium hydroxide from waste brines

Waste brines from various industrial processes, mainly from saltworks, are an important source of minerals, such as magnesium, table salt and potable water.

SELECTIVE CRYSTALLISATION OF MAGNESIUM AND CALCIUM HYDROXIDES FROM INDUSTRIAL WASTE BRINES: A PILOT STUDY

In the last years, a rising interest has been focused on the valorization of waste brines from industrial processes, such as desalination plants. In most current scenarios, waste brines are disposed directly, or after being treated, into a receiving water bodies, often causing environmental concerns and, more importantly, renouncing to the possibility of using such a waste as source of valuable raw materials. In fact, these brines are typically rich in useful salts and minerals, whose recovery can increase the environmental and economical sustainability of the industrial process [1-2]. The ZERO BRINE EU-H2020 project aims at the development of technologies for the recovery of salts, mineral…

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

A pilot-plant for the selective recovery of magnesium and calcium from waste brines

Abstract The problem of brines disposal has raised great interest towards new strategies for their valorisation through the recovery of minerals or energy. As an example, the spent brine from ion exchange resins regeneration is often discharged into rivers or lakes, thus impacting on the process sustainability. However, such brines can be effectively reconcentrated, after removal of bivalent cations, and reused for the resins regeneration. This work focuses on developing and testing a pilot plant for selective recovery of magnesium and calcium from spent brines exploiting a novel proprietary crystallization unit. This is part of a larger treatment chain for the complete regeneration of the …

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…

A simulation tool for ion exchange membrane crystallization of magnesium hydroxide from waste brine

Abstract Increasing attention is nowadays paid to the management and valorisation of industrial waste brines aiming also at the recovery of raw materials. Magnesium has been listed as a Critical Raw Material by EU, prompting researchers to investigate novel routes for its recovery. Within this framework, a novel Crystallizer with Ion Exchange Membrane (CrIEM), is proposed as an innovative way to recover magnesium from industrial waste brines exploiting low-cost alkaline reactants. In the present work, a novel mathematical model of the CrIEM process is proposed to provide a useful tool for its design in different working conditions. Batch and feed & bleed continuous configurations have been …

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…