In the published article [...]

Impact of desalination on the general circulation of the Arabian Gulf: Present and future scenarios.

Numerical simulation of desalination brine discharges: Effects of inlet boundary conditions

This study introduces an innovative hybrid approach combining salting-out and adsorption for the highly efficient removal of crystal violet (CV) dye from aqueous solutions. The method leverages high-ionic-strength brine discharge from the Complex of El-Outaya (CEO, ENASEL, Biskra, Algeria) and micro-mesoporous biochar derived from calves’ horn cores (BHC-800). Results demonstrate that both undiluted and diluted brine significantly enhance CV removal, while BHC-800, with a surface area of 258 m2 g−1, exhibits a maximum Langmuir adsorption capacity of 106.1 mg g−1 (at 20 °C ± 2). Thermodynamic analysis confirms a spontaneous (ΔG° < 0) and exothermic (ΔH° = −0.86 kJ mol−1) process, with increased interfacial disorder (ΔS° = 93.53 J mol−1 K−1). The synergistic effect of salting-out and adsorption achieved ~99.8% removal of CV at an initial concentration of 1000 mg L−1. Furthermore, BHC-800 exhibited excellent reusability, maintaining high adsorption efficiency over multiple cycles. Economic assessment revealed operational costs of 0.45–0.89 US$ m−3 for 60% brine discharge. Biochar production costs were 0.076–0.18 US$ kg−1, translating to 7.5–17.2 (10−4 US$) per gram of CV removed. This dual strategy not only offers an eco-friendly and cost-effective solution for dye-laden water but also promotes the valorization of saline effluents and animal byproducts, addressing critical environmental challenges in industrial wastewater treatment.

Numerical simulation of wellbore temperature effects on pipe column crystallization during hydrogen storage and brine discharge in salt caverns

Operational optimization of bipolar membrane electrodialysis for acid and base production in zero liquid discharge of high-salinity brine

Environmental Impact Assessment of Brine Discharge from Desalination Facilities via Bioindicators

Brine discharge from seawater reverse osmosis (SWRO) plants poses critical environ-mental and operational challenges, particularly in regions reliant on large-scale desalination. This study proposes a hybrid brine treatment system integrating Forward Osmosis (FO) and Membrane Distillation (MD) to enhance water recovery and minimize ecological impact. The FO stage utilizes a concentrated magnesium chloride (MgCl₂) draw solution to extract water from high-salinity brine without the need for hydraulic pressure, while the MD stage regenerates the draw solution using low-grade solar thermal energy, simultaneously producing high-purity distillate. Mass and energy balance calculations were per-formed to evaluate recovery rates, specific energy consumption, and thermal input requirements. The results indicate that the FO–MD configuration can achieve recovery rates exceeding 80% with significantly reduced brine discharge, while maintaining low energy demand compared to conventional methods. The integration of solar energy further enhances system sustainability, making it suitable for deployment in off-grid or arid regions. This hybrid approach demonstrates strong potential for advancing sustainable desalination practices, aligning with circular water strategies and zero liquid discharge (ZLD) objectives.

With the global freshwater scarcity, Seawater desalination particularly through reverse osmosis (RO), is a solution to address the problem. Nowadays, seawater desalination is used in various countries, like The United Arab Emirates (UAE), Africa and China, etc. However, despite its huge benefits, the technology is also accompanied by adverse environmental effects, like brine discharge which can lead to localized changes in salinity and subsequently affect the water quality and biodiversity of the area. Huge energy consumption is another issue, as most seawater desalination plants need the electrical energy to control the high-pressure pump which means the enormous energy requirement. Noise pollution, CO₂ emissions, biofouling and invasive species also impact on marine ecosystems. These effects can be minimized by innovative solution, such as improving RO membrane, zero liquid discharge technology, renewable energy technologies, energy recovery devices and continuous environmental monitoring and regulation. This paper investigates ecological consequences in seawater desalination processes, highlights the potential adverse effects, and discusses the mitigation measures.

Coastal Bangladesh faces severe drinking water scarcity due to salinity intrusion. To address this challenge, the study assesses the socio-technical and economic factors shaping the performance of small-scale reverse osmosis (RO) desalination plants through field audits, household surveys, stakeholder interviews, and water quality analysis. Community acceptance was evaluated using the Theory of Planned Behavior (TPB). Feedwater was highly contaminated, with average TDS 3732.63 mg/L, hardness 636.36 mg/L, iron (Fe) 3.23 mg/L, and turbidity 14.63 NTU. Despite this, RO systems demonstrated strong performance, achieving removal efficiencies of 95.15% for salts, 95.95% for hardness, and 91.67% for alkalinity, with an average recovery rate of 37.25% (range: 20–60%). Treated water met WHO and Bangladesh standards, with mean concentrations of TDS (195.54 mg/L), Fe (0.21 mg/L), arsenic (0.0085 mg/L), and turbidity (1.09 NTU). However, inadequate operator training and a lack of maintenance threaten sustainability. Energy consumption increased by 0.1 kWh/m3 per 1000 mg/L rise in salinity, while financial constraints hinder membrane replacement. TPB analysis revealed positive attitudes and perceived behavioral control as key adoption drivers. Untreated brine discharge (mean TDS 12,900 mg/L) posed significant environmental risks. This study provides micro-level insights to inform policy and strengthen the sustainability of decentralized RO systems in climate-vulnerable coastal regions.

Abstract The escalating challenge of water scarcity, intensified by climate change and rapid population growth, necessitates innovative strategies for securing and enhancing water resources. This study emphasizes artificial recharge and seawater desalination as two sustainable solutions to this critical issue. Traditional surface recharge methods often face limitations, such as evaporative losses up to 40%, contamination risks, and significant land requirements exceeding 1 hectare per 100,000 m³ of recharge capacity. In contrast, drywells provide a compact and efficient alternative, typically requiring less than 20 m² of land per unit. Field applications and experimental studies indicate that well-designed drywells can achieve infiltration rates between 0.5 and 5.0 m³/h, with cumulative recharge volumes exceeding 10,000 m³/year per well under optimal hydrogeological conditions. Their effectiveness is significantly influenced by soil permeability (10⁻³ to 10⁻⁵ m/s) and vadose zone thickness, with recharge efficiencies reaching up to 80% when clogging is minimized. Operational protocols that include intermittent resting phases can maintain over 90% of initial infiltration capacity throughout multi-year operations. However, monitoring data reveal that urban runoff often introduces elevated nitrate concentrations (frequently above 50 mg/L) and heavy metals, highlighting the need for thorough pre-treatment or site-specific assessments. Numerical modeling tools are being utilized to simulate unsaturated flow, optimize well spacing, and predict long-term aquifer storage gains, achieving modeled recharge improvements of 15–25% compared to unoptimized designs. Concurrently, desalination technologies for seawater and brackish groundwater are increasingly incorporated into water supply strategies, particularly in arid and coastal regions facing severe freshwater shortages. Reverse osmosis systems have achieved energy consumption levels as low as 2.5–3.0 kWh/m³, significantly more efficient than thermal distillation methods, which consume 10–15 kWh/m³. However, the environmental concern of brine discharge remains significant. By integrating drywell recharge systems with desalination technologies and broader water management frameworks, this study outlines a scientific pathway for sustainable resource development. Modeling and pilot projects suggest that coupling desalination with managed recharge can reduce net energy consumption by up to 30%, enhance aquifer resilience, and mitigate salinization risks through the dilution of high-salinity groundwater with recharged freshwater. This review consolidates existing knowledge on drywell recharge and desalination technologies, highlighting their fundamental principles and key characteristics.

Environmental impact of brine from desalination plants on marine benthic diatom diversity.

Effects of brine discharges on early benthic stages of Concholepas concholepas.

Trends in the study and impacts of brine discharge on benthic communities.

This case study offers an analysis of the operational efficiency and performance metrics of the Indonesia Desalination and Salt (sodium chloride, NaCl) Production Plant, located in Serang City, Indonesia. The plant stands as a pioneering model in seawater desalination, integrating advanced membrane-based technologies to meet the high demands for desalinated water and food-grade salt production in a region characterized by fluctuating climatic conditions. The study examines each component of the plant's infrastructure, including the pretreatment system, seawater nanofiltration (SWNF) system, seawater reverse osmosis (SWRO) system, and thermal system. Of particular note is the world's largest commercially available membrane-based food grade brine concentration system, which significantly enhances the plant's overall recovery rate and efficiency. The research delves into the design considerations, process variables, and energy consumption patterns, offering insights from the plant's commissioning phase through its current operations. The plant's design is tailored to Indonesia's unique geographical and environmental conditions, capable of adapting to the varying characteristics of seawater between monsoon and dry seasons. This adaptability is critical in maintaining consistent production levels while optimizing energy use, with specific power consumption rates monitored and analyzed. The integration of osmotically assisted reverse osmosis (OARO) systems and advanced brine management technologies further underscores the plant’s commitment to innovation and sustainability. These systems not only improve water and salt production efficiencies but also minimize the environmental impact by effectively managing brine discharge. This case study serves as a vital resource for understanding the complexities and technological advancements in modern desalination and brine concentration systems, offering a blueprint for future projects aiming to balance resource utilization with environmental stewardship.

While desalination is a key solution for global freshwater scarcity, its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems. Solar interfacial evaporation offers sustainable management potential, yet inevitable salt nucleation at evaporation interfaces degrades photothermal conversion and operational stability via light scattering and pathway blockage. Inspired by the mangrove leaf, we propose a photothermal 3D polydopamine and polypyrrole polymerized spacer fabric (PPSF)-based upward hanging model evaporation configuration with a reverse water feeding mechanism. This design enables zero-liquid-discharge (ZLD) desalination through phase-separation crystallization. The interconnected porous architecture and the rough surface of the PPSF enable superior water transport, achieving excellent solar-absorbing efficiency of 97.8%. By adjusting the tilt angle (θ), the evaporator separates the evaporation and salt crystallization zones via controlled capillary-driven brine transport, minimizing heat dissipation from brine discharge. At an optimal tilt angle of 52°, the evaporator reaches an evaporation rate of 2.81kgm-2h-1 with minimal heat loss (0.366 W) under 1-sun illumination while treating a 7 wt% waste brine solution. Furthermore, it sustains an evaporation rate of 2.71kgm-2h-1 over 72h while ensuring efficient salt recovery. These results highlight a scalable, energy-efficient approach for sustainable ZLD desalination.

Hydrogen production is increasingly vital for global decarbonization but remains a water- and energy-intensive process, especially in arid regions. Despite growing attention to its climate benefits, limited research has addressed the environmental impacts of water sourcing. This study employs a life cycle assessment (LCA) approach to evaluate three water supply strategies for hydrogen production: (1) seawater desalination without brine treatment (BT), (2) desalination with partial BT, and (3) freshwater purification. Scenarios are modeled for the United Arab Emirates (UAE), Australia, and Spain, representing diverse electricity mixes and water stress conditions. Both electrolysis and steam methane reforming (SMR) are evaluated as hydrogen production methods. Results show that desalination scenarios contribute substantially to human health and ecosystem impacts due to high energy use and brine discharge. Although partial BT aims to reduce direct marine discharge impacts, its substantial energy demand can offset these benefits by increasing other environmental burdens, such as marine eutrophication, especially in regions reliant on carbon-intensive electricity grids. Freshwater scenarios offer lower environmental impact overall but raise water availability concerns. Across all regions, feedwater for SMR shows nearly 50% lower impacts than for electrolysis. This study focuses solely on the environmental impacts associated with water sourcing and treatment for hydrogen production, excluding the downstream impacts of the hydrogen generation process itself. This study highlights the trade-offs between water sourcing, brine treatment, and freshwater purification for hydrogen production, offering insights for optimizing sustainable hydrogen systems in water-stressed regions.

Abstract Solar‐driven interfacial evaporation has emerged as a sustainable strategy for high‐salinity brine treatment, yet salt crystallization on evaporators severely limits evaporation efficiency and long‐term stability. While most research focuses on enhancing evaporation rates and preventing salt accumulation, the economic and ecological value of simultaneous salt collection is often overlooked. Achieving both efficient evaporation and high salt collection remains a major challenge. Here, we present a tree‐inspired biomimetic evaporator (TBE) is presented that leverages co‐directional Marangoni flows, driven by synergistic thermal and solute gradients, to enable directional salt crystallization and autonomous salt collection. In a one‐week continuous test with 23 wt.% brine, the TBE achieved an exceptional evaporation rate of 6.29 kg m−2 h−1, a salt production rate of 1.08 kg m−2 h−1, an automatic salt detachment rate of 94.1%, and zero liquid discharge (ZLD). Moreover, the TBE exhibited a high freshwater production rate of 4.30 kg m−2 h−1 and a salt collection rate of 0.45 kg m−2 h−1 in outdoor tests. This work provides a scalable, energy‐efficient solution to address both freshwater scarcity and brine pollution, aligning with UN Sustainable Development Goals (SDGs) 6 (Clean Water) and 14 (Life Below Water) by eliminating harmful brine discharge and reducing reliance on fossil fuels.

The accumulation of insoluble sediments at the bottom of salt caverns significantly affects the effective storage capacity and long-term operational stability of salt cavern gas storage facilities. To investigate the sediment accumulation processes under varying operating conditions and their impact on cavern performance, computational fluid dynamics (CFD) methods were employed to conduct two-dimensional numerical simulations using Fluent software. The Euler–Euler multiphase model and the standard k-ε turbulence model were adopted to quantify how parameters, including the distance between the brine discharge outlet and the sediment surface, sediment density, sediment height, and injection pressure, influence sediment deposition behavior. Simulation results indicate that numerical modeling is an effective approach for analyzing sediment flow and deposition processes under different conditions. The distance between the brine discharge outlet and the sediment surface critically governs the potential for sediment ingestion into the tubing. A shorter distance increases the likelihood of sediment being drawn into the tubing, whereas a greater distance promotes sediment deposition at the cavern bottom and minimizes entrainment, thus achieving optimal accumulation control. By optimizing the positioning of the brine discharge outlet relative to the sediment surface, the efficiency of sediment discharge can be significantly improved, thereby ensuring the long-term operational reliability of salt cavern gas storage facilities. The implementation of optimized discharge strategies effectively reduces adverse effects of sediment accumulation, enhances gas storage capacity and operational efficiency, and ensures the long-term safety and stability of the facility. These improvements yield substantial economic and social benefits for natural gas storage and peak-shaving operations.

Seawater desalination is considered the first option to meet the domestic and industrial requirements of freshwater in desert areas, such as the Atacama Desert (Chile). However, its environmental implications remain poorly characterized. This study evaluated the effects of brine discharge from a desalination plant located in Caldera Bay, where fishing and tourism coexist. Sampling was conducted at increasing distances from the outfall to assess physicochemical parameters, sediment metal content, and nutrient concentrations. The results revealed a clear spatial gradient: salinity decreased from 57.75 to 34.87 PSU and nitrate from 10.49 to 4.05 µM. The sediment samples near the outfall showed elevated concentrations of Al, Fe, and Cr(VI). These findings suggest that brine discharge alters water chemistry and sediment quality. This study highlights the need for long-term environmental monitoring and regulatory frameworks to ensure sustainable desalination in sensitive coastal systems.