Enhancing water resource recovery: Ozone-ultrafiltration-forward osmosis process for simultaneous tannery wastewater treatment and seawater desalination

Hydrogen production via water electrolysis using desalinated seawater offers a sustainable energy solution and has attracted considerable attention in recent years. However, its efficiency depends heavily on the quality of water. Many studies have not explored the relationship between treated water quality and hydrogen generation efficiency at each stage of the seawater desalination process. This study examines a three-step seawater desalination process comprising softening with ballasted flocculation (SBF) as a pretreatment, reverse osmosis (RO) as the main desalination step, and ion exchange as a polishing step to provide high-quality water for electrolysis. Water from each purification stage was supplied to the electrolyzer to compare the impact on water quality and hydrogen generation efficiency. The SBF process removed magnesium (Mg) and calcium (Ca) from seawater, as well as turbidity and bacteria, but hydrogen production via water electrolysis continued for no more than 10 h. However, when feeding RO water and RO water processed by ion exchange after the SBF process, hydrogen was generated stably and continuously for 70 h, achieving high efficiency comparable to that of commercial pure water. High production of green hydrogen by water electrolysis is possible through RO seawater desalination combined with SBF pretreatment.

Incorporating corrosion design constraints in desalination process optimization: A case study in mechanical vapor compression

As surface-active functional compounds, defoamers play a pivotal role in seawater desalination processes. In this study, a polyether-modified silicone compound was synthesized, and its structure was confirmed through FITR and 1H-NMR characterization. Using this compound as the main component, a more effective and stable composite defoamer product was obtained through a co-optimization method. The particle size of the defoamer ranged from 600 to 700 nm in aqueous systems, and the surface tension could be reduced to 27.46 mN/m, thereby exhibiting superior defoaming and antifoaming properties. Additionally, the defoamer demonstrated good compatibility with commonly used scale inhibitors and was non-corrosive to equipment. Industrial testing further confirmed its efficacy in controlling foam during seawater desalination effectively.

Advanced optimization of a biogas-based multigeneration multi effect distillation system integrated with desalination process for enhancing sustainable energy resource efficiency: CatBoost-supported multi objective multi-verse optimization

This dataset provides experimental measurements to quantify the rate of CO₂ release from (sea)water. Two different conditions were tested: vacuum pressure and 30°C and ambient pressure and 100°C. Data were collected using 1) a vacuum setup consisting of vacuum flask, placed in a thermostat bath at 30°C connected to a vacuum pump, protected by a cold trap and 2) a beaker without vacuum setup for the atmospheric experiments. Rates were inferred by measuring pH and the total inorganic carbon (TIC) in the water. The latter was measured ex-situ using a TIC analyzer. The TIC concentrations were corrected for reduced volume of the residue to the original volume to determine the actual CO2 release after each timestep. Actual seawater samples were utilized to determine the relationship between CO₂ release and water residence time under vacuum and ambient pressure boiling circumstances. The dataset includes variables such as CO₂ release rates and pH changes over time that the sample was subject to boiling conditions, providing valuable insights for designing process equipment for marine Carbon Dioxide Removal (mCDR) applications (for example in evaporative desalination processes) in both atmospheric and sub atmospheric pressures.

Graphene oxide (GO) is a promising nanomaterial for membrane-based desalination due to its tunable interlayer structure and abundant surface functionalities. This study synthesized and characterized a graphene oxide titanium dioxide (GO–TiO₂) composite membrane via vacuum-assisted filtration to enhance seawater desalination performance. Characterization using XRD, FTIR, SEM, and contact angle analysis confirmed uniform TiO₂ incorporation, which expanded GO interlayer spacing from 0.77 nm to 0.90 nm, increased hydrophilicity, and improved structural stability. Forward osmosis (FO) tests using 3.5 wt% NaCl feed solution showed that the GO–TiO₂ membrane achieved over 99% salt rejection and a 125% increase in water flux compared to pristine GO membranes. TiO₂ acted as a nano-spacer and hydrophilic agent, reducing GO restacking and facilitating water transport. These results indicate that the GO–TiO₂ composite membrane offers enhanced permeability, selectivity, and durability, making it a promising candidate for sustainable seawater desalination.

Accurate modeling of seawater thermophysical and thermodynamic properties is critical for optimizing desalination processes. This study compares three seawater property models, a Reaktoro multicomponent model, the thermophysical seawater properties library from the Massachusetts Institute of Technology, and a simplified sodium chloride model, in the context of levelized cost of water (LCOW) minimization for reverse osmosis (RO) and mechanical vapor compression systems. Process simulations and cost optimizations reveal that although all three models yield comparable LCOW and specific energy consumption (SEC) estimates under baseline conditions, deviations among their predictions increase with salinity. Relative differences in LCOW and SEC reach up to 6% and 8%, respectively. RO results show greater variability due to differences in osmotic pressure predictions, which affect pressure constraints at high recoveries. Computational performance varies substantially; specifically, Reaktoro simulations are up to 28 times slower than empirical models due to their detailed equilibrium calculations. These results suggest that empirical models offer acceptable accuracy for routine desalination process design, while Reaktoro provides advantages in scenarios requiring detailed speciation, such as scaling or pH adjustment studies. These findings underscore the importance of selecting appropriate property models based on the modeling objective of desalination applications and motivate future work integrating thermodynamic rigor with empirical efficiency.

This study introduces a novel hybrid model for an electromembrane stack, unifying an equivalent electrical circuit model incorporating specific resistance () and capacitance () parameters with an empirical fouling model in a single framework. The model simplifies the traditional approach by serially connecting N () ion exchange membranes (anionic PC-SA and cationic PC-SK) and is validated using and solutions in comparison with laboratory tests using various voltage signals, including direct current and electrically pulsed reversal operations at frequencies of 2000 and 4000 Hz. The model specifically accounts for the chemical stratification of the cell unit into bulk solution, diffusion, and Stern layers. We also included a calibration method using correction factors () to fine-tune the electrical current signals induced by voltage stimulation. The empirical component of the model uses experimental data to simulate membrane fouling, ensuring consistency with laboratory-scale desalination processes performed under pulsed reversal operations and achieving a prediction error of less than 10%. In addition, a comparative analysis was used to assess the increase in electrical resistance due to fouling. By integrating electronic and empirical electrochemical data, this hybrid model opens the way to the construction of simple, practical, and reliable models that complement theoretical approaches, signifying an advance for a variety of electromembrane-based technologies.

Mineral extraction from brine solutions is a vital issue for resource recovery in many fields of industry, especially in desalination processes. Usually, the solubility limit is viewed as a key factor that plays a determinant role in the efficiency of a prescribed process. This paper suggests the investigation of the influence of ionic strength, which is a measure of the total concentration of all dissolved ions, on the solubility limits in brines that are extracted from desalination facilities in Kuwait before discharging them into the Persian Gulf. For this purpose, the solubility of two main minerals (CaSO4 and Mg(OH)2) was measured for several values of ionic strength achieved by adjusting the concentration of the brine solutions. Brine samples were characterized and concentrated to achieve ionic strength values that are in the range of 1.1–2.0 mol/L. An adapted supersaturation-equilibration method was applied to determine solubility limits. Results show a non-linear relationship between ionic strength and the solubility limit of the target minerals, with behavior similar to that which could be found in the literature. In the case of CaSO4, it was found that the solubility exhibits an increase (salting in effect) at low ionic strength, followed by a decrease at higher ionic strength (>1.1 M) (salting-out effect). On the other hand, the solubility of Mg(OH)2 in Kuwait brine water was shown to decrease as the ionic strength increased. These trends, validated against literature data, are attributed to non-ideal solution behavior and specific ion interactions in the complex brine matrix. The findings of this work provide crucial insights for process design, enabling more precise control over precipitation steps and enhancing the overall yield and economic viability of mineral extraction from complex brine resources.

Mathematical modeling of desalination and brine concentration processes in batch recirculating electrodialysis system

Desalination processes have become crucial in addressing global freshwater scarcity. However, the by-products of these processes, mainly brine and bittern, pose significant environmental challenges. Brine, primarily composed of sodium chloride, and bittern, a concentrated liquid after salt extraction, both contain valuable chemicals and minerals that can be repurposed for industrial applications. This paper explores the chemical composition, industrial uses, and environmental impacts of brine and bittern, specifically in agriculture, pharmaceuticals, and energy sectors. Through laboratory analysis, case studies, and data interpretation, this paper aims to highlight the potential of these by-products for sustainable industrial innovation.

This research investigates the effect of seawater intrusion on groundwater quality in the western coastal zone of the Mediterranean Sea, Egypt, between Wadi Abu Emera and Abu-Hesha. The objective of this research is to study the effect of seawater intrusion on groundwater quality, using geoelectrical techniques including vertical electrical resistivity soundings (VES) and time-domain electromagnetic methods (TEM). Ten Schlumberger VES with a current electrode distance of as high as 600 m and twenty TEM soundings with a single loop of 200 × 200 metres were carried out during this study. Processing and interpretation of the field data concluded that the geoelectrical succession of the area consists of three layers, where the bottom layer is the water-bearing formation. Also, the resistivity values decrease with depth and towards the Mediterranean Sea because of the seawater intrusion. This intrusion occurs along a system of faults that act as conduits to bring seawater inland. It is recommended to avoid the locations of these faults while drilling wells unless these wells are used for the desalination process. These faults serve as conduits for seawater to migrate inland. In contrast, the southern portion of the survey area is suitable for well drilling, provided that careful measures are implemented to maintain the wells' safe yield.

The crisis of clean water availability has become increasingly critical due to rapid population growth and environmental degradation. One strategic approach to address this challenge is to implement seawater desalination, which provides an abundant, sustainable water source. However, conventional methods remain limited in terms of energy efficiency. This study aims to analyze the effect of pressure and temperature variations on the performance of a large-capacity desalination reactor with an 8000-liter tank. Two configurations were experimentally tested: (1) an air-circulation system that relies on static heating assisted by an axial fan to enhance convection, and (2) a sealed system operating under low-pressure conditions to reduce the boiling point of water, equipped with active hot-water circulation. Data collection was carried out over 27 hours of operation, with the observed parameters including water temperature, partial pressure, relative humidity, and evaporation volume. The experimental results showed that the sealed configuration delivered superior performance, with an evaporation rate 16.64% higher than that of the air-circulation variant. The volume of water successfully evaporated in the sealed system reached 20.12 liters, whereas in the air-circulation system it was only 17.25 liters. This increase in efficiency is attributed to the pressure-reduction effect, which enhances the vapor pressure difference while facilitating uniform heat distribution through active water circulation. This study emphasizes that controlling pressure and temperature is key to improving the effectiveness of the desalination process, thereby supporting the Development of more energy-efficient and sustainable clean water supply technologies.

Background: Soil salinization reduces the availability of micronutrients, which are essential for producing functional foods such as corn. This makes it increasingly difficult to grow food in saline soils that meet the required nutritional standards for human health. Therefore, improving soil quality through the adoption of proper farming practices is vital to ensure the continued production of functional foods and their associated health benefits. Objective: The research was conducted from 2021 to 2024 in the Mrgashat community of the Metsamor region, Armavir marz, RA, under field conditions. The desalination and dealkalization processes and their impact on germination, growth, yield, qualitative characteristics, chemical composition, and functionality of the "Turbo" corn subtype were studied under varying flushing water standards. Methods: The study focused on improving saline-alkaline soils through chemical melioration with sulfuric acid, using different amounts of flushing water (25%, 50%, and 100% of the calculated norm). The effects of these treatments on the soil and the qualitative properties and chemical composition of corn were assessed. Results: With the full sulfuric acid dose (7.1 kg) and 25% flushing water (9.6 m³), a decrease in soil chemical indicators was observed. Still, the corn seeds did not germinate, suggesting an insufficient combination of ameliorant and water for effective desalination. These data can serve as a basis for assessing the extent of flushing water's effect on desalination efficiency. When 50% flushing water (19.2 m³) was used, topsoil amelioration occurred, but significant salt accumulation remained in the deeper soil layers. Partial seed germination indicated that this amount of flushing water was not enough for complete salt removal. Using 100% flushing water (38.3 m³) with the full sulfuric acid dose (7.1 kg) resulted in complete desalination and alkalinization. A marked increase in calcium (Ca) in the adsorption complex was observed, enhancing plant growth and yield. In the first year of sowing, the yield reached 29.0 qt/ha, indicating that a higher flushing water dose significantly improved soil conditions and increased yield. Novelty: This research is the first in the RA to examine the effects of different flushing water amounts on the efficiency of saline-alkaline soil amelioration and on corn growth, germination, yield, and functionality. The study emphasizes that proper selection of flushing water volume is crucial for effective salt removal, and that the combination of the ameliorant and water should be optimized to maximize desalination efficiency and high-functioning food production. Conclusion: The research demonstrates that varying amounts of flushing water significantly influence the efficiency of soil desalination and alkalinization. The use of 100% flushing water ensures complete desalination, improves soil chemical composition, and increases both corn yield and quality. These findings provide a basis for selecting optimal melioration practices to improve saline-alkaline soils and enhance functional food production. Keywords: Soil salinization, desalination, dealkalization, flushing water, melioration, sulfuric acid, corn, functional food.

The design of a solar-driven interfacial evaporator applied to the process of seawater desalination has attracted great attention due to sustainable renewable solar energy. The underlying mechanisms linking the evaporator structure to its functional performance have yet to be comprehensively established. In this study, we prepared a three-dimensional (3D) porous structured molybdenum disulfide (MoS2) evaporator aerogel by using MoS2 nanosheets as photothermal materials and polyacrylamide hydrogel as immobilization carriers. And MoS2 evaporator aerogel was systematically characterized using various methods. We detailly investigated the influence of the structure characteristics (i.e., the vertical pore channels, the LAR value (which refers to the ratio of light area to effective evaporation area) and volume size) of the 3D evaporators on the evaporation rate and salt resistance performance. The results implied that the MoS2 evaporator aerogel could make full use of the environment energy. Smaller LAR and volume could improve the evaporation performance of the evaporator. In 3.5 wt % salt water, MoS2 evaporator aerogel was evaporated at the rate of 4.07 kg·m-2·h-1 and the photothermal conversion efficiency was 91.84%, without salt crystals produced on its surface. These findings will be helpful to get a deeper understanding of the correlation between the structural characteristics of an evaporator and its evaporation performance for the design of the solar-driven interfacial evaporator applied to the process of seawater desalination.

ABSTRACT Hybridization of two or more desalination processes has been identified as an attractive option for improved energy efficiency and recovery rate. To appropriately assess the performance enhancement of hybrid desalination systems, an integrated approach for energy, exergy, economic, and environmental investigations should be adopted. This study considers the energy, exergy, and economic analysis of integrated mechanical vapor compression (MVC) and membrane distillation (MD) processes. Various MVC–MD hybrid configurations have been proposed and modeled. Exergy analysis revealed the escalation of destroyed work as the operating brine temperature rises because of increasing demand for compression power. It is also found that the incorporation of MD reduces the exergy losses to 25.53 kW, which amounts to 38.5% enhancement, and increases exergy efficiency to 0.63, which sums to 23.5% improvement. The compressor unit is found to exhibit unbalanced exergy of 12.94 kW, which is equivalent to 51% of the total exergy losses. The MD and the distillate preheater units are found to be the least exergy destructive components as their corresponding exergy efficiency approaches 0.96 and 0.86, respectively. Economic analysis indicates that the optimal water production cost occurs when the operating brine temperature resides between 60°C and 70°C depending on the cost of electricity. The optimum condition can be extended to higher temperatures when a very low electricity tariff is used. For nominal value for the electricity tariff of $0.06/kWh, the levelized water cost approaches $2.12/m 3 at brine temperature of 60°C. Moreover, the specific water cost can be reduced to $1.95/m 3 when the MVC production capacity is upgraded to 8 kg/s (691.2 m 3 /day). This optimum also occurs at brine temperature 60°C, which is also promoted by the exergy analysis findings as irreversibility descends at low operating temperatures.

Water scarcity and distribution constitute a problem driven by population growth and industrial overexploitation. To secure water supply, desalination technologies for seawater and brackish water have been adopted, becoming critically important. Reverse osmosis is the highest-rated technology for this process and generates two output streams: permeate water and brine, the latter characterized by a high concentration of total dissolved solids (TDS). When untreated, brine is discharged into water bodies and soils, causing ecological damage. To mitigate this impact, the circular economy proposes reusing part of the brine in agriculture through halophyte plants, which offer the advantage of growing under high salt concentrations. The objective of the research was to document the salinity tolerance of halophyte species and the potential use of water rejected from the desalination process as irrigation water, with a circular economy approach. Brine reuse represents an opportunity to reduce waste and generate environmental, social, and economic benefits. Among the main halophyte species capable of tolerating brine above 30 000 mg L-1 are Suaeda salsa (L.) Pall., Salicornia bigelovii Torr., Rhizophora mangle L., and Chenopodium quinoa Willd. Salicornia europaea L. is classified as a halophyte species with medium tolerance (10 000–30 000 mg L-1). Species with low salinity tolerance (5000–10 000 mg L-1 TDS) include Atriplex nummularia Lindl., Zoysia japonica Steud., and Crithmum maritimum L. These plants also possess significant nutritional and pharmaceutical properties and can be used as livestock feed, human food, for oil extraction, soil remediation, and other applications.

The study of soil water-salt transport mechanisms is of great significance for salinity control and sustainable agricultural development. In recent years, carbon-based materials (e.g., biochar, straw-derived charcoal) have significantly enhanced the water infiltration capacity and desalination efficiency of saline-alkali soils by improving soil physical structure, regulating salt ion adsorption, and enhancing microbial activity. The porous structure and surface functional groups of biochar promote water movement and immobilize salt ions such as Na+ and Cl-, while straw mulching and incorporation reduce soil salinity risks by suppressing evaporation, optimizing pore structure, and driving microbial desalination processes. Meanwhile, the integration of numerical models (e.g., Green-Ampt, HYDRUS) with machine learning techniques has provided new tools for precise simulation of water-salt transport and optimization of carbon-based material application. This paper systematically reviews the mechanisms of water-salt transport regulation by carbon-based materials and advances in model applications, exploring their potential in sustainable agriculture and ecological restoration, thereby offering theoretical support for the resource utilization of saline-alkali soils in the era of new energy.

Water scarcity is a growing global issue, necessitating innovative and sustainable solutions for freshwater generation. Among the available technologies, reverse osmosis (RO) has become the primary method for seawater desalination due to its effective salt rejection and high energy efficiency. This study presents an integrated experimental and analytical investigation of a full-scale seawater reverse osmosis (SWRO) plant with a 2 MLD capacity at the Victoria and Alfred (V&A) Waterfront in Cape Town, South Africa. Operational data were collected over six months, including feedwater temperature (13.66 –16.78 °C), pressure (50–60 bar), total dissolved solids (32,883–38,387 mg/L), and pH (6.19–7.89). The plant consistently produced high-quality permeate with TDS around 500 mg/L, achieving a 31% recovery rate at an average energy consumption of 3 kWh/m³. Machine learning models, specifically multiple linear regression and decision trees, were used to predict RO performance and to explore the relationships between operational parameters. Results show that higher feed pressure improves permeate flux but raises energy use, increased feedwater temperature boosts flux and slightly reduces energy consumption, while deviations from near-neutral pH negatively impact product quality and efficiency. The novelty of this work lies in combining real plant operational data with predictive analytics to establish parameter-based performance relationships and identify optimal operating ranges (e.g., feed pressure ~52–55 bar, pH ~7). These insights provide a strong foundation for optimizing desalination processes, improving membrane efficiency, and guiding the design and operation of future RO desalination projects.