Nowadays, small remote islands rely heavily on desalination technologies to overcome freshwater scarcity. Unfortunately, these technologies are accompanied by the production of brines which can affect the receiving water bodies i.e., the aquatic ecosystem. Yet, it is extremely appealing how such brines constitute an abundant source of valuable raw materials (such as magnesium). In this work, a novel hybrid system is introduced to capture the value of seawater reverse osmosis (SWRO) brines produced in the minor Sicilian island of Pantelleria. The “Minimal Liquid Discharge” (MLD) process consists of: (i) Nanofiltration NF (separation of bivalent from monovalent ions), (ii) Mg Reactive Crystallizer MRC (selective recovery of magnesium and calcium), (iii) Multi-Effect Distillation MED (freshwater production) and (iv) NaCl Thermal Crystallizer NTC (sodium chloride recovery). The economic and environmental performances of the process have been evaluated by implementing and integrating the techno-economic models of each unit in a simulation platform called RCE (Remote Component Environment). Results revealed important economic benefits in comparison to conventional brine disposal methods. In addition, the proposed MLD chain turned out to be an attractive alternative for the production of high purity minerals/salts, achieving lower selling prices than the current market price.@en

Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes have been widely proposed in the recent scientific literature not only as a possible solution to brine disposal but also as a non-conventional sustainable source of raw materials. Nevertheless, very few works have pushed the idea towards a real demonstration activity, and this somehow limits the reliability that such schemes have with respect to the real implementation potential at the industrial scale. In this work, for the first time in the literature, an integrated treatment chain for the sustainable production of freshwater and minerals has been demonstrated at a pre-industrial scale, in the island of Lampedusa (Italy). The treatment chain included a Nanofiltration (NF) step to separate monovalent and bivalent ions, followed by a Multi-Effect Distillation (MED) unit, powered by waste heat from a Thermal Power plant, generating high-quality water (<30 μS/cm) and an ultra-concentrated brine. The latter was treated in Evaporation Ponds (EPs) to generate high purity NaCl (>99 %). On the other side, the NF retentate was treated to selectively recover magnesium and calcium hydroxides (Mg(OH)2 purity up to 98 %) in a novel Multiple Feed-Plug Flow Reactor (MF-PFR). The resulting brine fed an ElectroDialysis with Bipolar Membranes unit (EDBM), generating in-situ alkaline and acidic solutions: chemicals needed for internal usage in the plant. All units were successfully tested, reaching satisfactory performance indicators. Furthermore, the stability of each unit during the daily operational run was assessed and successfully achieved, demonstrating not only the technical feasibility of the proposed demo plant, but also the feasibility of MLD as a sustainable alternative for minerals recovery.@en

Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes have been widely proposed in the recent scientific literature not only as a possible solution to brine disposal but also as a non-conventional sustainable source of raw materials. Nevertheless, very few works have pushed the idea towards a real demonstration activity, and this somehow limits the reliability that such schemes have with respect to the real implementation potential at the industrial scale. In this work, for the first time in the literature, an integrated treatment chain for the sustainable production of freshwater and minerals has been demonstrated at a pre-industrial scale, in the island of Lampedusa (Italy). The treatment chain included a Nanofiltration (NF) step to separate monovalent and bivalent ions, followed by a Multi-Effect Distillation (MED) unit, powered by waste heat from a Thermal Power plant, generating high-quality water (<30 μS/cm) and an ultra-concentrated brine. The latter was treated in Evaporation Ponds (EPs) to generate high purity NaCl (>99 %). On the other side, the NF retentate was treated to selectively recover magnesium and calcium hydroxides (Mg(OH)2 purity up to 98 %) in a novel Multiple Feed-Plug Flow Reactor (MF-PFR). The resulting brine fed an ElectroDialysis with Bipolar Membranes unit (EDBM), generating in-situ alkaline and acidic solutions: chemicals needed for internal usage in the plant. All units were successfully tested, reaching satisfactory performance indicators. Furthermore, the stability of each unit during the daily operational run was assessed and successfully achieved, demonstrating not only the technical feasibility of the proposed demo plant, but also the feasibility of MLD as a sustainable alternative for minerals recovery.@en

Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes have been widely proposed in the recent scientific literature not only as a possible solution to brine disposal but also as a non-conventional sustainable source of raw materials. Nevertheless, very few works have pushed the idea towards a real demonstration activity, and this somehow limits the reliability that such schemes have with respect to the real implementation potential at the industrial scale. In this work, for the first time in the literature, an integrated treatment chain for the sustainable production of freshwater and minerals has been demonstrated at a pre-industrial scale, in the island of Lampedusa (Italy). The treatment chain included a Nanofiltration (NF) step to separate monovalent and bivalent ions, followed by a Multi-Effect Distillation (MED) unit, powered by waste heat from a Thermal Power plant, generating high-quality water (<30 μS/cm) and an ultra-concentrated brine. The latter was treated in Evaporation Ponds (EPs) to generate high purity NaCl (>99 %). On the other side, the NF retentate was treated to selectively recover magnesium and calcium hydroxides (Mg(OH)2 purity up to 98 %) in a novel Multiple Feed-Plug Flow Reactor (MF-PFR). The resulting brine fed an ElectroDialysis with Bipolar Membranes unit (EDBM), generating in-situ alkaline and acidic solutions: chemicals needed for internal usage in the plant. All units were successfully tested, reaching satisfactory performance indicators. Furthermore, the stability of each unit during the daily operational run was assessed and successfully achieved, demonstrating not only the technical feasibility of the proposed demo plant, but also the feasibility of MLD as a sustainable alternative for minerals recovery.@en

Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes have been widely proposed in the recent scientific literature not only as a possible solution to brine disposal but also as a non-conventional sustainable source of raw materials. Nevertheless, very few works have pushed the idea towards a real demonstration activity, and this somehow limits the reliability that such schemes have with respect to the real implementation potential at the industrial scale. In this work, for the first time in the literature, an integrated treatment chain for the sustainable production of freshwater and minerals has been demonstrated at a pre-industrial scale, in the island of Lampedusa (Italy). The treatment chain included a Nanofiltration (NF) step to separate monovalent and bivalent ions, followed by a Multi-Effect Distillation (MED) unit, powered by waste heat from a Thermal Power plant, generating high-quality water (<30 μS/cm) and an ultra-concentrated brine. The latter was treated in Evaporation Ponds (EPs) to generate high purity NaCl (>99 %). On the other side, the NF retentate was treated to selectively recover magnesium and calcium hydroxides (Mg(OH)2 purity up to 98 %) in a novel Multiple Feed-Plug Flow Reactor (MF-PFR). The resulting brine fed an ElectroDialysis with Bipolar Membranes unit (EDBM), generating in-situ alkaline and acidic solutions: chemicals needed for internal usage in the plant. All units were successfully tested, reaching satisfactory performance indicators. Furthermore, the stability of each unit during the daily operational run was assessed and successfully achieved, demonstrating not only the technical feasibility of the proposed demo plant, but also the feasibility of MLD as a sustainable alternative for minerals recovery.@en

Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes have been widely proposed in the recent scientific literature not only as a possible solution to brine disposal but also as a non-conventional sustainable source of raw materials. Nevertheless, very few works have pushed the idea towards a real demonstration activity, and this somehow limits the reliability that such schemes have with respect to the real implementation potential at the industrial scale. In this work, for the first time in the literature, an integrated treatment chain for the sustainable production of freshwater and minerals has been demonstrated at a pre-industrial scale, in the island of Lampedusa (Italy). The treatment chain included a Nanofiltration (NF) step to separate monovalent and bivalent ions, followed by a Multi-Effect Distillation (MED) unit, powered by waste heat from a Thermal Power plant, generating high-quality water (<30 μS/cm) and an ultra-concentrated brine. The latter was treated in Evaporation Ponds (EPs) to generate high purity NaCl (>99 %). On the other side, the NF retentate was treated to selectively recover magnesium and calcium hydroxides (Mg(OH)2 purity up to 98 %) in a novel Multiple Feed-Plug Flow Reactor (MF-PFR). The resulting brine fed an ElectroDialysis with Bipolar Membranes unit (EDBM), generating in-situ alkaline and acidic solutions: chemicals needed for internal usage in the plant. All units were successfully tested, reaching satisfactory performance indicators. Furthermore, the stability of each unit during the daily operational run was assessed and successfully achieved, demonstrating not only the technical feasibility of the proposed demo plant, but also the feasibility of MLD as a sustainable alternative for minerals recovery.@en