Search results for "RISA"

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

2021

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 …

Effective magnesium recovery via seawater brines mining

In the last couple of decades, a rising interest has been focused on the research of novel and unconventional sources for mining minerals, such as industrial waste brines. As an example, brines are produced by desalination plants and discharged directly, or after being treated, into receiving water bodies possibly causing environmental concerns and renouncing the possibility to recover minerals [1,2]. Within this framework, the Water Mining WU-H2020 project aims at implementing an advanced Zero Liquid Discharge (ZLD) demo systems for the extraction of minerals and valuables products from industrial waste brines through a circular approach. The ZLD demo plant consists of: (i) Nano Filtration…

Operational analysis of a novel reactive crystallizer for the production of Magnesium Hydroxide from waste brines

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

2020

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

2021

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…

Bipolar membrane reverse electrodialysis for the sustainable recovery of energy from pH gradients of industrial wastewater: Performance prediction by…

2021

Abstract The theoretical energy density extractable from acidic and alkaline solutions is higher than 20 kWh m−3 of single solution when mixing 1 M concentrated streams. Therefore, acidic and alkaline industrial wastewater have a huge potential for the recovery of energy. To this purpose, bipolar membrane reverse electrodialysis (BMRED) is an interesting, yet poorly studied technology for the conversion of the mixing entropy of solutions at different pH into electricity. Although it shows promising performance, only few works have been presented in the literature so far, and no comprehensive models have been developed yet. This work presents a mathematical multi-scale model based on a semi-…

A Novel Ionic Exchange Membrane Crystallizer to Recover Magnesium Hydroxide from Seawater and Industrial Brines

2020

A novel technology, the ion exchange membrane crystallizer (CrIEM), that combines reactive and membrane crystallization, was investigated in order to recover high purity magnesium hydroxide from multi-component artificial and natural solutions. In particular, in a CrIEM reactor, the presence of an anion exchange membrane (AEM), which separates two-compartment containing a saline solution and an alkaline solution, allows the passage of hydroxyl ions from the alkaline to the saline solution compartment, where crystallization of magnesium hydroxide occurs, yet avoiding a direct mixing between the solutions feeding the reactor. This enables the use of low-cost reactants (e.g., Ca(OH)2) without …

ELECTRICAL ENERGY STORAGE DEVICES BASED ON pH AND SALINITY GRADIENTS: MODELLING, EXPERIMENTS AND PILOTING

2021

Electrodialysis Applications in Wastewater Treatment for Environmental Protection and Resources Recovery: A Systematic Review on Progress and Perspec…

2020

This paper presents a comprehensive review of studies on electrodialysis (ED) applications in wastewater treatment, outlining the current status and the future prospect. ED is a membrane process of separation under the action of an electric field, where ions are selectively transported across ion-exchange membranes. ED of both conventional or unconventional fashion has been tested to treat several waste or spent aqueous solutions, including effluents from various industrial processes, municipal wastewater or salt water treatment plants, and animal farms. Properties such as selectivity, high separation efficiency, and chemical-free treatment make ED methods adequate for desalination and othe…

L’ILLECITO ANTITRUST DOPO LA DIRETTIVA 2014/104/UE

2020

Tradizionalmente, tanto a livello nazionale quanto a livello comunitario, la tutela della concorrenza si è caratterizzata per l’impiego di strumenti di enforcement pubblicistico. Dopo un lungo iter, il 26 novembre 2014 è stata pubblicata la direttiva del Parlamento Europeo e del Consiglio UE 2014/104 relativa a determinate norme che regolano le azioni per il risarcimento del danno ai sensi del diritto nazionale per violazioni delle disposizioni del diritto della concorrenza degli Stati membri e dell'Unione europea. In Italia il recepimento della Direttiva è avvenuto il 19 gennaio 2017 con il d.lgs. n. 3/2017. Sebbene la normativa in parola intervenga a colmare il vuoto creato dall’assenza, …