Desalination Brine Research Articles

Integration of ion exchange resins and membrane technology for purification of boron from seawater desalination brines

Integration of ion exchange resins and membrane technology for purification of boron from seawater desalination brines

Efficient magnesium recovery from seawater desalination brine via CO2 mineralization to synthesize hydromagnesite for uranium extraction

Magnesium (Mg2+) is the most abundant resource in the seawater desalination brine. The efficient and economical extraction of Mg2+ is crucial for recovery of other ions. In this work, we proposed a facile and cost-effective method to completely transform Mg2+ to hydromagnesite via carbon dioxide (CO2) mineralization. The effects of the injection time of CO2, concentration of sodium hydroxide solution, reaction temperature, and aging time on the synthesis of hydromagnesite and utilization ratios of Mg2+ and CO2 were investigated. The synthesized hydromagnesite exhibited flower-like spherical morphology, and the utilization ratios of Mg2+ and CO2 could reach 99.91 % and 87.75 %, respectively. The formation process of hydromagnesite was illustrated by the time-dependent experiment. The synthesized hydromagnesite was applied to the uranium extraction with the coinstantaneous high maximum adsorption capacity and adsorption efficiency. Especially, it could exhibit good selectivity with the adsorption capacity of 0.32 mg·g−1 and adsorption efficiency of approaching 90 % in 5 L of natural seawater for 10 days. The cycling experiments suggested that the synthesized hydromagnesite possessed the good stability. Therefore, the recovery of Mg2+ to synthesize hydromagnesite via CO2 mineralization is a high-efficiency and low-cost method; meanwhile, the synthesized hydromagnesite shows promising application prospects in the uranium extraction.

SWRO Brine Characterisation and Critical Analysis of Its Industrial Valorisation: A Case Study in the Canary Islands (Spain)

The most recent years of research have shifted the perception of desalination brine from being waste to a high-value resource, in consonance with a circular economy perspective. The Canary Islands, containing the largest number of desalination plants per square kilometre in the world, are a perfect location to study its characteristics and evaluate its potential. A total of 10 heterogeneous seawater reverse osmosis plants were selected to determine the brine’s physicochemical characterisation, comprising 37 parameters, and its correlation to the technical and operational aspects of the desalination plants. The results show a stable narrow range of the percentage of major ions concentration in relation to the total dissolved solids (55% Cl−, 29.5% Na+, 8% SO42−, 4% Mg2+, 1.5% Ca2+, 1.2% K+, 0.5% HCO3−, and 0.2% Br−) irrespective of specific differences between plants. The results obtained in this study are highly beneficial to industrial suppliers and future users of desalination brine valorisation (DBV) technologies, allowing an estimation of the chemical composition of a brine through knowledge only of its conductivity. Such information is crucial before investing in and optimizing DBV technologies. Nonetheless, from an environmental, economic, operational, energy-based, and R&D point of view, several improvements are required to promote their large-scale feasibility and viability.

A new concept for complex mining of mineral raw material resources from DTEK coal mines based on sustainable development and ESG strategy

Purpose. The research purpose is to develop a concept for complex mining of mineral resources from coal mines using the example of PJSC DTEK Pavlohradvuhillia mines with a transition to multi-product production of clean drinking water, utilization of methane, secondary coal from rock dumps and sludge reservoirs, low-potential thermal energy of mine groundwaters and associated raw materials from desalination waste. Methods. The research uses an integrated approach, which includes an analysis of existing experience and available complex coal mining technologies, laboratory studies of mine water desalination technology by the reverse osmosis method with thermal distillation of concentrated brine, and chemical analysis using ElvaX laboratory equipment. Findings. This paper presents the research results of a comprehensive analysis of mineral raw material resources related to coal mining. The technically achievable energy potential that can be produced from the secondary coal of rock dumps and sludge reservoirs has been determined, which in total is 183.3 TJ. The annual heat potential of methane gas utilization has been estimated, which in total of PJSC DTEK Pavlohradvuhillia’s mines reaches 7.1 PJ. The possibility of extracting up to 1.12 TJ/year of associated thermal energy from the water-drainage installation of mine complexes has been determined. For the conditions of the Zakhidno-Donbaska mine, the authors of the paper have developed a technological scheme for the water preparation process by the reverse osmosis with the desalination brine treatment by the method of multistage evaporation on adiabatic evaporators. Originality. For the first time, the energy flows related to coal mining technology have been comprehensively analyzed for the possibility of their joint use to cover the needs of the mine complex. The prospects for complex mining of mineral resources have been assessed based on the adaptation of the mine complex production facilities to the multi-product production of clean drinking water, utilization of methane gas, low-potential thermal energy from mine groundwaters and secondary raw materials of desalination waste. Practical implications. The proposed set of technological solutions will ensure the sustainable development and diversification of the production of PJSC DTEK Pavlohradvuhillia coal-mining enterprises, as well as the effective transformation of coal-mining cities during the period of transition from mono-product production to the creation of multi-business production complexes that comply with ESG principles. The creation of multi-product mine complexes capable of producing not only coal, but also heat and associated mineral raw material resources, should become a guarantee of stable social-economic development of coal-mining regions.

Architecting Janus hydrogel-fabric coupled evaporator for eliminating salt accumulation and highly efficient solar-driven brine desalination

Here, a novel Janus photothermal hydrogel-fabric was developed by firmly formatting surface hydrophobized porous photothermal hydrogel on a commercial cotton fabric in large area. This Janus-architected hydrogel-fabric not merely inherits the “water activation” effect of hydrogel-based evaporator, but also combines the good mechanical property of cotton fabric. In laboratory evaporation under 1 sun illumination (1 kW m−2), this novel hydrogel-fabric coupled evaporator achieved evaporation rate up to 1.60 kg m−2 h−1 from pure water, as well as 1.55 kg m−2 h−1 from 3.5 wt% NaCl solution, exceeding the theoretical limit of plane evaporators. It also has been confirmed no salt accumulation on the photothermal hydrogel-fabric surface and no evaporation performance degradation occurring in the multicycle long-time continuous evaporation testing in saline water and simulated industrial dyeing water. Additionally, 6.3 kg m−2 of freshwater was produced from 3.5 wt% NaCl solution in 9 h under natural sunlight (average 0.46 sun, Sep. 23th 2022 in Shanghai, China), showing a great potential to seawater desalination for freshwater supply in the coastal and insular area. Considering the simple process in large-scale preparation, and efficient but also stable solar evaporation performance, this novel hydrogel-fabric coupled evaporator could promote the solar evaporation technology to large-scale application in real industrial fields.

Production of Sodium Bicarbonate with Saline Brine and CO2 Co-Utilization: Comparing Modified Solvay Approaches

The present work investigates the production of sodium bicarbonate in combination with the co-utilization of saline brine and carbon capture, utilization, and sequestration (CCUS). The use of ammonia in the traditional Solvay process could be eliminated by using a modified Solvay process. This study compared the modification with the addition of three buffering additives: Ca(OH)2, KOH, and NH4HCO3. The effectiveness of these processes, using two qualities of saline brine (desalination and aquifer), is compared based on the purity of the produced NaHCO3. It was found that the use of Ca(OH)2 did not produce high-purity NaHCO3, while NH4HCO3 and KOH performed better. Desalination brine utilization with NH4HCO3 resulted in the production of high-purity NaHCO3, while the second most suitable method involved the use of KOH, and the main co-product formed was Na2CO3. Geochemical modeling is performed in order to have insights into the carbonation (in the reactor) and precipitation (in the oven) behavior of the reactions. It predicted the precipitation of mineral phases well, though kinetics might hinder some saturated solids to dissolve first. The present study shows that accurate characterization is critical to accurately assess the success of modified Solvay processes. The use of QXRD and SEM analyses, complemented with geochemical modeling, helped to better understand the processes and the formation of NaHCO3. Further investigations on diverse brines could provide for their better utilization by the geological carbon sequestration and water desalination industries that produce them.

Performance of Hypersaline Brine Desalination Using Spiral Wound Membrane: A Parametric Study.

Desalination of hypersaline brine is known as one of the methods to cope with the rising global concern on brine disposal in high-salinity water treatment. However, the main problem of hypersaline brine desalination is the high energy usage resulting from the high operating pressure. In this work, we carried out a parametric analysis on a spiral wound membrane (SWM) module to predict the performance of hypersaline brine desalination, in terms of mass transfer and specific energy consumption (SEC). Our analysis shows that at a low inlet pressure of 65 bar, a significantly higher SEC is observed for high feed concentration of brine water compared with seawater (i.e., 0.08 vs. 0.035) due to the very low process recovery ratio (i.e., 1%). Hence, an inlet pressure of at least 75 bar is recommended to minimise energy consumption. A higher feed velocity is also preferred due to its larger productivity when compared with a slightly higher energy requirement. This study found that the SEC reduction is greatly affected by the pressure recovery and the pump efficiencies for brine desalination using SWM, and employing them with high efficiencies (ηR ≥ 95% and ηpump ≥ 50%) can reduce SEC by at least 33% while showing a comparable SEC with SWRO desalination (<5.5 kWh/m3).

Electrochemical Interfacial Polymerization toward Ultrathin COF Membranes for Brine Desalination.

Ultrathin covalent organic framework (COF) membranes are urgently demanded in molecular/ionic separations. Herein, we reported an electrochemical interfacial polymerization strategy to fabricate ultrathin COF membranes with thickness of 85 nm, by actively manipulate self-healing effect and self-inhibiting effect. The resulting COF membrane exhibited superior performance in brine desalination with the permeation flux of 92 kg m-2 h-1 and the rejection of 99.96 %. Our electrochemical interfacial polymerization strategy enriches the fabrication approach of COF membranes and facilitates the rational design of ultrathin membranes.

Electrochemical Interfacial Polymerization toward Ultrathin COF Membranes for Brine Desalination

AbstractUltrathin covalent organic framework (COF) membranes are urgently demanded in molecular/ionic separations. Herein, we reported an electrochemical interfacial polymerization strategy to fabricate ultrathin COF membranes with thickness of 85 nm, by actively manipulate self‐healing effect and self‐inhibiting effect. The resulting COF membrane exhibited superior performance in brine desalination with the permeation flux of 92 kg m−2 h−1 and the rejection of 99.96 %. Our electrochemical interfacial polymerization strategy enriches the fabrication approach of COF membranes and facilitates the rational design of ultrathin membranes.

Analysis of Operational Parameters in Acid and Base Production Using an Electrodialysis with Bipolar Membranes Pilot Plant

In agreement with the Water Framework Directive, Circular Economy and European Union (EU) Green Deal packages, the EU-funded WATER-MINING project aims to validate next-generation water resource solutions at the pre-commercial demonstration scale in order to provide water management and recovery of valuable materials from alternative sources. In the framework of the WATER-MINING project, desalination brines from the Lampedusa (Italy) seawater reverse osmosis (SWRO) plant will be used to produce freshwater and recover valuable salts by integrating different technologies. In particular, electrodialysis with bipolar membranes (EDBM) will be used to produce chemicals (NaOH and HCl). A novel EDBM pilot plant (6.4 m2, FuMa-Tech) has been installed and operated. The performance of EDBM for single pass under different flowrates (2-8 L·min-1) for acid, base and saline channels, and two current densities (200 and 400 A·m-2), has been analyzed in terms of specific energy consumption (SEC) and current efficiency (CE). Results showed that by increasing the flowrates, generation of HCl and NaOH slightly increased. For example, ΔOH- shifted from 0.76 to 0.79 mol·min-1 when the flowrate increased from 2 to 7.5 L·min-1 at 200 A·m-2. Moreover, SEC decreased (1.18-1.05 kWh·kg-1) while CE increased (87.0-93.4%), achieving minimum (1.02 kWh·kg-1) and maximum (99.4%) values, respectively, at 6 L·min-1.

Desalination effects on macroalgae (part A): Laboratory-controlled experiments with Dictyota spp. from the Pacific Ocean and Mediterranean Sea

Desalination brines from direct seawater intake that get discharged to coastal areas may produce stress responses on benthic marine communities, mostly due to its excess salinity, and especially on sessile organisms; in this context, macroalgae have been understudied in desalination ecotoxicological investigations. In this study, we assessed the short- and long-term cellular tolerance responses in two brown species of the macroalgae genus Dictyota through controlled laboratory conditions. Dictyota kunthii was collected from the eastern Pacific Ocean (average salinity, ~34 psu), whereas Dictyota dichotoma was from the Mediterranean Sea (average salinity, ~37 psu). Each macroalgae species was exposed for up to 7 days to two conditions with increased salinity values: +2 and +7 psu above their natural average salinity. Photosynthetic parameters and oxidative stress measurements were determined. The results showed that, in both Dictyota species, high salinity values induced reduced photoinhibition (Fv/Fm) but increased the primary productivity (ETRmax) and light requirement (EkETR) especially after 7 days. Conversely, the photosynthetic efficiency (αETR) decreased in hypersalinity treatments in D. dichotoma, while there were no changes in D. kunthii. The reactive oxygen species hydrogen peroxide (H2O2) was greater at high salinity values at 3 days for D. dichotoma and after 7 days in D. kunthii, while lipid peroxidation decreases under hypersalinity with time in both species. Despite the evident H2O2 accumulation in both species against hypersalinity, it did not produce oxidative damage and important impairment in the photosynthetic apparatus. These results contribute to understanding the tolerance strategies at the cellular level of Dictyota spp., which may be considered as potential candidates for biomonitoring of desalination impacts in the field.

Role of Nanoscale Morphology on the Efficiency of Solvent-Based Desalination Method

Brine desalination is important for minimizing the environmental impact of contaminated wastewater, yet current desalination techniques have high energy requirements. Solvent-based desalination (SBD) method, which is the process of extracting fresh water using an organic solvent, has existed for decades, yet has not reached competitive efficiencies. In this work, 10 organic solvents were tested for SBD efficacy via synergetic studies using bench-scale extraction experiments and molecular dynamics (MD) simulations. The SBD effectiveness was correlated to the computationally observed ability of the solvent to form one of the three morphologies in water: ordered, disordered, or partial nanoscale. We correlated that solvents that form ordered and disordered morphologies were not able to clean up the water. Solvents that were able to cause low salinity in water showed computationally observed partial nanoscale phase separation, where nanometer-scale aggregated solvent phases were able to effectively reject salt ions while capturing comparatively large amounts of water molecules. The formation of a partial nanoscale phase is likely driven by the solvent structure with bulky hydrocarbons adjacent to hydrophilic end groups. Our results make a step toward the rational design of solvents that may allow for efficient SBD and thus a low-cost source of fresh water.

Design of solar evaporator with well-aligned and multi-scale fluid channels based on convection tuning for stable and efficient brine desalination

Desalination based on interfacial solar evaporation is emerging as one of the most promising water treatment technologies. However, the inevitable salt-accumulation at the evaporation interface is still a major challenge facing the long-term application. Herein, a salt-resistant evaporator (SRE) is proposed under the guidance of computational fluid dynamics simulation. Theoretical simulation clearly suggests that well-aligned multiscale channels represent the optimal geometry of the photothermal evaporator, as they contribute high hydraulic conductivity and diffusion flux and derivate strong convection. During solar evaporation, these channels provide the pathways for the rapid transfer of bulk brine, which excretes the salt and self-regenerates the evaporator in real time. Rattan naturally features regular multiscale channels. Consequently, this sustainable biomass material is employed to carbonize and assemble the desired SRE. This rattan-based evaporator exhibits a high evaporation rate (1.47 kg m−2 h−1) and efficiency (91 %) in a highly concentrated brine (20 wt% NaCl) under 1 sun. Owing to the convection effect tuning, its performance is kept constant during a continuous week operation, indicative of the long-term stability of the system. Moreover, convective effect tuning can be generalized to other photothermal materials, which opens up the possibilities for large-scale application of solar desalination of high salinity brine.

Membrion receives funding for membrane monitoring system and forms strategic partnership

In the USA, a grant from the Department of Energy is helping Membrion Inc to fund a project that will enable it to develop a monitoring system for use in the mass-production of high-quality membranes. It has also formed a strategic partnership with a company based in Texas to create next-generation technology for high-recovery desalination of groundwater and waste brines.

Effects of Groundwater Abstraction and Desalination Brine Injection on a Middle Miocene Aquifer of the El-Dabaa Area, Northern Coast of Egypt

Effects of Groundwater Abstraction and Desalination Brine Injection on a Middle Miocene Aquifer of the El-Dabaa Area, Northern Coast of Egypt

Non-target screening and prioritization of organic contaminants in seawater desalination brine using comprehensive two-dimensional gas chromatography-mass spectrometry

Non-target screening and prioritization of organic contaminants in seawater desalination brine using comprehensive two-dimensional gas chromatography-mass spectrometry

Evaluation of pressure-assisted forward osmosis for concentrating desalination brine: a feasibility study

Evaluation of pressure-assisted forward osmosis for concentrating desalination brine: a feasibility study

Geochemical carbon dioxide removal potential of Spain

Many countries have made pledges to reduce CO2 emissions over the upcoming decades to meet the Paris Agreement targets of limiting warming to no >1.5 °C, aiming for net zero by mid-century. To achieve national reduction targets, there is a further need for CO2 removal (CDR) approaches on a scale of millions of tonnes, necessitating a better understanding of feasible methods. One approach that is gaining attention is geochemical CDR, encompassing (1) in-situ injection of CO2-rich gases into Ca and Mg-rich rocks for geological storage by mineral carbonation, (2) ex-situ ocean alkalinity enhancement, enhanced weathering and mineral carbonation of alkaline-rich materials, and (3) electrochemical separation processes. In this context, Spain may host a notionally high geochemical CDR capacity thanks to its varied geological setting, including extensive mafic-ultramafic and carbonate rocks. However, pilot schemes and large-scale strategies for CDR implementation are presently absent in-country, partly due to gaps in current knowledge and lack of attention paid by regulatory bodies. Here, we identify possible materials, localities and avenues for future geochemical CDR research and implementation strategies within Spain. This study highlights the kilotonne to million tonne scale CDR options for Spain over the rest of the century, with attention paid to chemically and mineralogically appropriate materials, suitable implementation sites and potential strategies that could be followed. Mafic, ultramafic and carbonate rocks, mine tailings, fly ashes, slag by-products, desalination brines and ceramic wastes hosted and produced in Spain are of key interest, with industrial, agricultural and coastal areas providing opportunities to launch pilot schemes. Though there are obstacles to reaching the maximum CDR potential, this study helps to identify focused targets that will facilitate overcoming such barriers. The CDR potential of Spain warrants dedicated investigations to achieve the highest possible CDR to make valuable contributions to national reduction targets.

Experimental and economic evaluation of nanofiltration as a pre-treatment for added-value elements recovery from seawater desalination brines

Desalination brine mining emerges as a solution to supply raw materials to the European Union industry in a circular economy approach since valuable minerals and metals (e.g., B(III), Mg(II), Ca(II), Sc(III), V(V), In(III), Ga(III), Li(I), Mo(VI), Rb(I)) are present in seawater but in low concentrations. Brine pre-treatment is important to remove species that may impair the performance of other technologies involved and to increase recovery efficiencies. Hence, nanofiltration and calcium precipitation were proposed as pre-treatment stages. Nanofiltration was studied to separate monovalent from multivalent elements (Fonsalía desalination plant case study), while economically, it was evaluated whether it would be better to place it before (Scenario 1) or after (Scenario 2) a Ca(II) precipitation stage, considering that Ca(II) can produce scaling in membranes. Three commercial membranes were tested using synthetic brines at 30 bar. Experiments (65 % permeate recovery) showed that Fortilife XC-N and PRO-XS2 membranes presented higher Ca(II) and Mg(II) rejection than NF270. Heating the brine for Ca(II) precipitation jeopardizes the economic feasibility of the project. Scenario 1 was the best configuration since it presented lower total levelized cost (≈1.6 €/m3 inlet, without heating the brine for Ca(II) removal). In such scenario, PRO-XS2 reported the best selectivity between monovalent and multivalent elements.

Economics of brine desalination for communities near the Salton Sea Geothermal Field, California, USA

Economics of brine desalination for communities near the Salton Sea Geothermal Field, California, USA