Green Desalination:
How to Solve the Brine Crisis?
By: Eman Mounir
By: Eman Mounir
This investigation is the fourth part of the series “The Cost of Fresh Water in the Arabian Gulf,” produced in partnership with the Pulitzer Centre’s Ocean Reporting Network (ORN), where Eman Mounir was a fellow.
It is now well-established that the brine produced by desalination poses a serious environmental challenge, threatening marine resources and ecosystems. Stories from fishermen, local communities, and researchers interviewed by Muwatin during its investigative series "The Cost of Fresh Water in the Arabian Gulf" highlight the scale of this crisis. However, despite its urgency, the issue remains without decisive strategies or practical solutions that can be implemented on a large scale.
Over a year, Muwatin conducted extensive interviews with nearly twenty researchers and scientists specializing in desalination technologies, many of whom have spent years working in the six Gulf Cooperation Council (GCC) states. The team also participated in key conferences, including the Euromed 2024 – Desalination for Clean Water and Energy conference, organized by the European Desalination Society (EDS) in Sharm El Sheikh, Egypt, from May 6 to 9, 2024.
The conference was marked by a surge of academic activity, with numerous scientific papers presented in search of effective solutions to the brine challenge caused by desalination. Yet, as Muwatin observed and experts confirmed, these solutions remain confined mainly to academic studies and have seen limited application in small-scale projects.
Researchers interviewed by Muwatin unanimously agreed that governments are well aware of the "brine crisis" and are actively seeking solutions. Carlos Duarte, Professor of Marine Science at King Abdullah University Of Science And Technology (KAUST), noted that the current trend in desalination research focuses on developing technologies that altogether avoid brine discharge. This approach reflects the growing desire to minimize environmental harm while maximizing freshwater extraction efficiency.
Based on a 2023 study published in the journal Water Resources and Industry titled "Governing desalination, managing the brine: A review and systematization of regulatory and socio-technical issues," seven proposed solutions have been identified to address the brine crisis. These solutions fall under three main categories:
However, despite the range of options, these solutions face significant real-world challenges, including legal constraints, regulatory hurdles, high costs, and limited access to the technology required for implementation.
Brine could be repurposed for therapeutic purposes, such as in treatment pools
This does not fully solve the issue of brine disposal.
Brine can be used to irrigate saline soils or restore wetlands.
This may lead to soil salinization, posing environmental risks.
Convert liquid waste into solids, allowing nearly complete water reuse.
ZLD is complex, expensive, and energy-intensive.
Disposing brine into deep wells or underground reservoirs.
This method is costly and risky due to potential leaks and corrosion.
Brine is discharged into regulated sites adhering to strict environmental standards.
Requires meticulous planning and regulation.
Using brine in carbon storage to reduce emissions.
Expensive and still in the experimental stage.
Recovering valuable minerals such as lithium or magnesium from brine
Most technologies are not commercially viable and require further research.
Harnessing energy from the salinity gradient (osmotic energy).
Current technologies are costly and inefficient.
Allowing water to evaporate, leaving behind salts for collection.
Risk of groundwater contamination and requires large land areas.
Mixing brine with seawater before discharge.
Reduces environmental impact but does not fully address salinity issues.
to extract more freshwater and produce less brine.
Requires innovative technologies or costly upgrades to existing systems.
in desalination processes with eco-friendly alternatives.
Requires research into the impact of substitutes on water quality and system sustainability.
I’ve always wondered why the ‘brine crisis’ hasn’t been resolved. Perhaps it’s the cost, but the Gulf states are wealthy enough to bear that expense, especially since it’s not a technically complex issue. This became evident when newer desalination plants like ‘Umm Al Houl’ were built using less polluting technologies. We monitored these plants and found no significant environmental impact because they employed evaporation and dilution to manage brine, reducing its harmful effects. However, the real issue lies in the lack of investment in these technologies by desalination plants, especially in the Gulf, which houses the world’s largest number of desalination plants.
Dr. Al-Saidi adds: The biggest challenge is the existing infrastructure. Incorporating new technologies into massive plants is difficult without disrupting water supplies. Solutions require gradual intervention and infrastructure upgrades, focusing on improving brine dilution techniques.
He continues: “While some solutions have been implemented on a small scale in countries like Saudi Arabia and the UAE, economic and political challenges make short-term solutions difficult. There’s also a pressing need for better policies to ensure the sustainability of water supplies.”
Dr. Al-Saidi believes that resolving the brine crisis in the Gulf could take up to two decades, especially with challenges related to climate change and increasing water demand.
Many researchers interviewed by Muwatin highlighted that while technological changes could resolve the brine crisis caused by desalination plants, the lack of strict regulatory frameworks hinders the full potential of these solutions. Regulatory tools for managing brine salinity vary between countries based on environmental and local conditions.
Dr. Al-Saidi explains: “We need clear and effective standards and mechanisms to monitor their implementation. However, looking at the available literature, it’s evident that compliance with such standards isn’t always strict. Even in countries like Saudi Arabia, where some standards exist, effective monitoring and clear plans for addressing non-compliance are essential.
Dr. Al-Saidi also reviewed studies that show how environmental regulations can drive technological innovation. He notes: “Once desalination plants are required to meet environmental limits and provide monitoring plans, it becomes a significant cost factor for them. This incentivizes innovation through new technologies or even by extracting and selling minerals from brine.”
He explains: "In the Gulf, we need to strengthen these environmental systems. However, as policymakers, we must recognize that the reality is different. Cities like Riyadh, Abu Dhabi, and Dubai rely on several desalination plants to meet their needs. Therefore, working closely with these plants is possible due to their limited number. However, we cannot impose strict environmental regulations if these plants are unable to implement them practically."
A 2023 research paper co-authored by Al-Saidi highlighted six common regulatory approaches worldwide for managing brine in a structured manner.
EIAs are a fundamental requirement for approving the construction of new desalination plants. They help identify the potential environmental impacts of such projects. In Chile, various types of assessments are used depending on the project and location.
These plans complement EIAs by identifying potential adverse environmental impacts and establishing monitoring procedures. In Chile, EMPs are commonly used, and their application is increasing. Spain also implements long-term monitoring plans to ensure comprehensive environmental evaluations.
Some countries establish specific standards for the quality of brine discharged into the sea, such as limits on salinity levels, temperature, or allowable chemical concentrations. These standards are strictly enforced in the United States, Canada, and Australia.
Certain regions allow the mixing of brine with seawater in designated areas to mitigate environmental impact. This practice is common in North America, where mixing zones are defined based on the properties of the brine and the local environment.
Some countries, like Spain, implement emergency measures when water quality levels exceed permissible thresholds. These measures include identifying the cause, taking steps to reduce environmental impacts, such as lowering discharge rates or diluting brine before release.
Some nations adopt broad regulations to protect marine ecosystems. These include Strategic Environmental Assessments (SEAs), which evaluate the long-term environmental impacts of activities like desalination. Marine Spatial Planning (MSP) also defines acceptable environmental load limits in specific areas.
Source: Governing desalination, managing the brine: A review and systematization of regulatory and socio-technical issues
Dr. Al-Saidi stresses the importance of remembering that laws and regulations are meaningless without an effective enforcement mechanism. He emphasizes the need to avoid imposing impractical laws and instead focus on gradually supporting desalination plants while comprehensively developing water infrastructure. This approach should include not only production but also reuse and storage. Through such a gradual strategy, desalination plants can be encouraged to enhance their environmental sustainability without disrupting operations or imposing sudden burdens.
Four years ago, King Abdullah University of Science and Technology (KAUST), in collaboration with Red Sea Global, launched a global engineering challenge titled “Brains for Brine.” The competition sought innovative ideas for brine utilization, attracting over 125 submissions. The first-place winner proposed a circular solution to the brine issue using technology to create an eco-friendly building material. Another idea involved redirecting brine to the Dead Sea, connected to the rift system north of the Gulf of Aqaba. The Dead Sea, which is experiencing a severe volume reduction due to water withdrawals from its basin, is approximately 470 meters below sea level.
Carlos Duarte notes that adding brine, with a salinity level of 250 grams of salt per liter of water, could help replenish the Dead Sea’s volume. The elevation difference would allow gravity to transport brine effectively. While geopolitical challenges complicate such a solution, Duarte highlights its technical feasibility and potential benefits.
Carlos Duarte explains: “The primary goal of desalination is to obtain freshwater as the main product. Seawater extracted in the Arabian Peninsula contains about 40 grams of salts per liter, while discharged brine concentrations range between 70 and 80 grams per liter. This means that for every liter of seawater pumped, 960 grams of desalinated water and the discharged brine contain 920 grams. Accordingly, only 40 grams of freshwater are extracted from every liter of seawater.”
He adds: “If all the salts in seawater could be utilized, it would allow the extraction of all the freshwater associated with them. This would reduce the volume of seawater that needs to be pumped and mitigate the risks of returning brine to the ocean.”
Duarte emphasizes that researching ways to use brine as a raw resource would bring significant benefits, especially for Gulf countries, which produce more than half of the world’s desalinated water. This poses a significant challenge in terms of energy consumption in the region.
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