Seawater Desalination Industry Research Articles

What does the seawater desalination industry need from polymer scientists?

AbstractThe seawater desalination industry does not need exotic two‐dimensional materials. However, it faces challenges in terms of membrane resilience to stressors such as temperature and oxidation and especially in the area of (bio)fouling. Membrane replacement is a large part of the operating expenditure of modern desalination plants and anything that increases the effective lifespan of a membrane will have economic impact. There are also emerging requirements for membrane selectivity, especially in desalination‐adjacent brine‐valorisation activities. These challenges provide abundant scope for the exercise of creativity by polymer scientists. © 2024 Society of Chemical Industry.

Occurrence, toxicity, and control of halogenated aliphatic and phenolic disinfection byproducts in the chlorinated and chloraminated desalinated water

Seawater desalination is widely used to overcome the freshwater shortage worldwide. However, even after three-stage reverse osmosis treatment, the desalinated water still contained 14.6 μg/L of aliphatic disinfection byproducts (DBPs), 384.2 ng/L of bromophenolic DBPs, 3.5 ng/L of iodophenolic DBPs, 1024.7 μg/L of Br-, 2.8 μg/L of I-, and 2.4 mg C/L of dissolved organic carbon (DOC). After the desalinated water was disinfected with chlor(am)ine, the concentrations of halogenated aliphatic and phenolic DBPs further increased, and bromophenolic DBPs were the toxicity forcing agents. When surface water was mixed with desalinated water and then chlorinated, the yield of aliphatic and phenolic DBPs significantly elevated. Separately chlorinating desalinated water and surface water before mixing could mitigate this adverse situation. Chloramine disinfection was more conducive to reducing the total calculated toxicity of disinfected desalinated waters and mixed waters compared to chlorine disinfection. The treatment of desalinated water with granular activated carbon could effectively remove DOC and UV254, leading to a reduction in the content of total organic halogen after chlor(am)ination. Although anion exchange resin could adsorb Br-, it also released the organic precursors of DBPs, ultimately increasing the yield of DBPs. The results of this study can provide a reference for the seawater desalination industry to improve seawater pre-treatment and desalination processes and thus minimize the DBPs.

Techno-economic analysis (TEA) of zero liquid discharge (ZLD) systems for treatment and utilization of brine via resource recovery

The issue pertaining to brine disposal has generated considerable interest in advanced methodologies aimed at harnessing their potential for resource recovery (i.e., water and salts). This techno-economic analysis investigates the technical and economic outlooks of zero liquid discharge (ZLD) desalination systems, employing two distinct crystallization approaches: membrane-promoted crystallization (MPC) in case 1, and wind-aided intensified evaporation (WAIV) in case 2. The findings indicate that case 1 exhibits a higher drinking water recovery rate (96 %) compared to case 2 (84 %), as the crystallization technology adopted in case 2 (WAIV) does not facilitate freshwater recovery. In both systems, the water is extracted via the implementation of efficient technologies, leading to the attainment of ZLD conditions along with minimal brine volumes. In terms of energy and cost requirements, case 1 necessitates a greater total energy demand (19 kWh/m3) and cost (US$95/day) in contrast to case 2 (15 kWh/m3 & US$83/day). Both cases demonstrate feasibility, yielding profits varying from US$179.19/day to US$221.32/day, contingent upon the sale of solely water or both water and solid salt. The insights provided by this study are poised to facilitate viable utilization and management of brine originating from the seawater desalination industry as well as from diverse brine-generating sectors.

Multi-dimensional low-carbon assessments of wind-driven seawater desalination system via hybrid life cycle modeling

Wind-driven desalination is a representative technology of renewable energy that not only alleviates water shortages but also reduces greenhouse gas (GHG) emissions generated by the utilization of fossil fuels. This study examined the GHG emissions from a wind-driven seawater desalination system by using the hybrid input-output life-cycle analysis (IO-LCA) to undertake a comprehensive low-carbon assessment by comparing with traditional thermal seawater desalination systems over the whole life cycle. The findings indicate that the GHG emissions of the wind-driven seawater desalination system are 96.14% lower than those of the traditional system. According to estimations, if reverse osmosis (RO) desalination is driven by wind power technologies at a larger scale, the annual GHG emissions can be reduced by an amount between 7.54E+05 and 3.71E+06 t CO2-eq. Although the construction stage increases the emissions to 55.41% over the whole life cycle, the payback period (Ypp) is about 2.69 years, which means that the level of GHG emissions could be reduced by 25.42% of the level of the traditional systems. Based on the multi-dimensional low-carbon assessment, this study is expected to provide quantitative assessments and policy implications to integrate low-carbon technologies with seawater desalination and promote sustainable development of seawater desalination industries.

Entry barriers and tripartite evolutionary game analysis of seawater desalination under the government regulation in China

Seawater desalination is a new promising marine industry and an important way to supplement the shortage of land water resources and promote the efficient use of seawater resources. Currently, the global desalination industry is rapidly developing. In China’s new development plan, large-scale development of the seawater desalination industry is also an important strategic goal. However, compared to the technological development of the seawater desalination industry, its marketization is affected by various factors, and its development level is still relatively low. Therefore, based on real industry data, this paper constructs a tripartite evolutionary game model for seawater desalination enterprises, water supply enterprises, and the government, and identifies several entry barriers for seawater desalination in China. The results include: (1) For seawater desalination to enter the market in China, government supervision limit should be no greater than 400,000 tons per day, about 13.8% of total seawater desalination scale. (2) The entry cost should be no more than 10 million yuan per day for seawater desalination, which is equivalent to approximately 18.25 trillion yuan during a five-year period. Finally, (3) political relatedness should be at least 2.0 for seawater desalination to take place, and 3.0 for it to develop in full swing. The paper also discusses the division of state- and foreign-owned water companies and reveals that government subsidies are only effective if foreign-owned companies seek rents. Based on the findings of the study, we propose pertinent policy recommendations including top-level planning, desalinated water infrastructure development, subsidy policy implementation, and public engagement. These recommendations aim to aid the Chinese government in fostering the desalination sector.

Defining Priority Areas for the Sustainable Development of the Desalination Industry in Chile: A GIS Multi-Criteria Analysis Approach

The climate crisis is rapidly provoking water scarcity in several areas of the planet, where an exponential growth of the seawater desalination industry is expected. In this context, multiple efforts are currently under development to reduce potential impacts and promote the sustainability of this industry. The selection of a suitable site for a desalination plant is critical to ensure operational continuity and the environmental sustainability of its processes, optimizing the plant’s productive performance and thus safeguarding water security for final users. In this study, we apply a GIS-based Multi-Criteria Analysis (GIS-MCA) approach to explore and assess potential areas suitable for the construction and operation of desalination plants in Chile. Different environmental, social, and technical criteria were evaluated and weighted by expert criteria using the Analytic Hierarchy Process (AHP) methodology. From a total of 114,450 km2 analyzed, only 4.54% of the territory was classified as highly suitable, demonstrating the scarcity of space available to meet the growth expectations for the industry. These results suggest that GIS-based analysis provides a practical solution to determine suitable areas for developing desalination plants, highlighting the need to define priority areas for the sustainable development of the desalination industry in Chile with the required capacity to reach the national water security goals for the following decades.

A systematic construction of water-electricity cogeneration and thermal membrane coupling desalination technology using the waste heat in steel industry

The widespread use of fossil energy emits a large amount of carbon dioxide, leading to the greenhouse effect and global warming. The essence of reducing carbon emissions is to achieve higher-quality sustainable development. The recycling of waste heat in the iron and steel industry is of great significance to reducing carbon emissions. Aiming at the problem of insufficient utilization of gas in iron and steel industry and the development of seawater desalination industry, a water-electricity cogeneration and thermal membrane coupling technology is established. Low-temperature multi-effect distillation seawater desalination device is directly connected with steam turbine generator, which uses gas to generate electricity. After generating electricity, negative pressure exhaust at the end of steam turbine is used for seawater desalination. The thermal efficiency of the system is increased to over 80%, the waste heat is effectively utilized, and the carbon emission in the thermal desalination process is reduced. At the same time, the high-efficiency removal and resource utilization of salt in concentrated seawater are realized. The recovery ratio of freshwater is over 55%, the salt content of freshwater is below 500 mg/L, and the salt content of seawater concentrated by membrane method can reach 79,450 mg/L. A new comprehensive utilization and recycling system of seawater has been constructed to realize efficient recycling of energy resources and promote the development process of carbon emission reduction.

Research on the economic and environmental impacts of China's seawater desalination industry with different technologies in the macroeconomic system

Reverse osmosis (RO) and multiple-effect distillation (MED) are China's main seawater desalination technologies. This paper made the cost analysis of RO and MED industries, compiled China's 2007, 2012 and 2017 input-occupancy-output tables with RO and MED industries specially separated, then estimated their economic and environmental impacts in China's macroeconomic system. Results show that RO and MED had a similar pulling effect on China's economy, and their pulling effects were higher than the average level of all 50 industries. From 2007 to 2017, the ranking of direct CO2 emission coefficient of MED industry rose from 5th to 3rd, and that of RO industry rose from 12th to 8th. Expanding the unit output of the seawater desalination industry brought more CO2 emission than the average level of all industries. Unit production of MED brought more CO2 emission than that of RO. With the CO2 emission APL model, the upstream three energy production industries, which had the strongest connection with the CO2 emission of RO and MED industries were identified. To reduce CO2 emission from RO and MED industries, it is practical to take CO2 emission reduction measures on the upstream three energy production industries.

Development status of global seawater desalination industry and dynamically comparative analysis of its production cost

This paper summarizes seawater desalination’s development status in China and abroad, then analyses its domestic development trend and attention through Baidu Index. Then compares the cost differences among RO, MED and other technologies in different scales and years and their change trend. Furthermore, the paper identifies the main impacting factors of production costs with RO and MED and evaluates their contributions to the cost through actual cases. The results show that: with the expansion of production scale and technological progress, the production cost of seawater desalination is gradually reduced, and the cost of RO and MED was reduced by 29.75% and 36.97% from 1999 to 2017, respectively. In the production cost of seawater desalination, power cost accounts for nearly 40%, and fixed asset investment accounts for about 20%. On a 100000 m3/d scale, the production costs with RO or MED in China are 26.85% and 22.50% higher than those of foreign countries, respectively. The production cost of seawater desalination is about 1.28 times of tap water and 1.20 times of reclaimed water in China. In the future, reducing the production cost of seawater desalination in China can be promoted through scientific investment and operation, technological progress and innovation, improving the cost structure, making up for the shortage of talents, and government guidance and support mutually.

Residents’ acceptance of using desalinated water in China based on the theory of planned behaviour (TPB)

In recent decades, water shortage has become a grave problem faced by countries all over the world. Seawater desalination, regarded as an alternative complement to water resources, has gained the attention of governments and scholars. China, particularly its coastal provinces, suffers from water shortage and has devoted considerable energy to promoting the seawater desalination industry. Nevertheless, the fact that residents in coastal regions are unwilling to use desalinated water restricts the large-scale development of desalination. By reviewing policy evolution and the status quo of desalination in China, this paper offers a new perspective for researchers on desalination, in which the theory of planned behaviour (TPB) is adopted to investigate residents’ acceptance towards the utilisation of desalinated water. We find that attitude, subjective norm and perceived behaviour control have significant positive effects on behavioural intention and further impact the use of desalinated water. Moreover, an interrelationship between subjective norm and attitude exists as well. In combination with a realistic situation, we further provide a series of corresponding implications for practice. This study is the first to investigate China’s desalination development under a micro perspective, aimed at providing reference and guidance for policymakers.

Modeling the effects of brine outflow from desalination plants on coastal food-webs of the Levantine basin (eastern Mediterranean Sea)

Population growth and climate change have led to an increasing demand for freshwater, and subsequently to an exponential growth of the seawater desalination industry in which the number of reverse osmosis-based plants is constantly increasing. The purpose of this study was to examine the possible impact of brine discharge on the marine food-web by constructing and analyzing food-web models from two desalination plant environments located along the Israeli coastline. The models were constructed using the Ecopath and Ecosim with Ecospace modeling suite, and analyses of collected samples were used for calibration and validation. Additionally, we conducted a series of scenarios in order to evaluate the impact of increased salinity and temperature on the food-web. A comparison between model output and measured isotopic δ15N values yielded a good fit. In addition, Ecopath results illustrated the importance of the zooplankton groups both in terms of biomass and trophic level. Ecospace results indicated that most functional groups biomass decreased compared to the "no desalination" scenario. The results indicate that elevated temperature most likely has a greater effect than increased salinity on the food-web, and that there is a general decrease in functional groups biomass due to desalination.

Identify competitive advantages and disadvantages of seawater desalination industry in China using the diamond model

Identify competitive advantages and disadvantages of seawater desalination industry in China using the diamond model

Applications and prospects of titanium and its alloys in seawater desalination industry

Seawater desalination (SD) is an effective method to solve the shortage of human water resources. Because of the excellent corrosion resistance of metallic materials in natural waters, as well as the best corrosion resistant, low density, high strength and good heat resistance in seawater, titanium and its alloys are considered the desirable marine material, including in SD equipment. This review introduces material characteristics of titanium and its alloys, and three currently most widely used commercial SD technologies: multiple effect desalination (MED), multi-stage flash (MSF) and reverse osmosis (RO). The applications and prospect of titanium and its alloys in SD industry are overviewed and analysed. This paper can be a reference for the future material selection of SD equipment.

DRFM hybrid model to optimize energy performance of pre-treatment depth filters in desalination facilities

Rapid depth filtration is the dominant pre-treatment technology in seawater desalination industry today. Optimizing the pre-treatment filter’s energy performance provides economies of scale in the total energy usage of desalination facilities on a broader sense. However, this objective remains difficult to achieve by far. In this study, we develop a numerical algorithm, termed as Dynamical Rapid Filtration Model (DRFM), to simulate the effective clogging dynamics occurring inside a depth filter which depends on a multitude of controlled and non-controlled operating parameters. DRFM quantifies the filtration kinetics with a modified Yao’s model to represent the particle removal mechanisms occurring within the simulated filter. A unique length scale is also introduced to account for the particle size effect on the filter’s energy loss rate incurred, i.e. its energy performance, during its effective filtration stage. Concurrently, we performed an experimental study with a lab-scale depth filter to develop a model equation for measuring its total contaminant mass removal rate (Rc) due to effective clogging conditions. For a predicted Rc transient profile, good agreement is obtained between the experimental results and predicted values from DRFM. We then extensively discuss on a novel DRFM hybrid model to optimize the filter’s energy performance which subsequently affects the filter’s optimized backwashing timing for achieving economies of scale. The simulation results from the hybrid model demonstrates on how various filter configurations can result in lower energy cost to effectively pre-treat each unit volume of intake seawater as compared to the current industrial average of 0.39kWh/m3. Finally, we include a cost analysis to demonstrate on how the obtained economies of scale alleviates a portion of the total energy cost for each unit volume of desalinated water.

The Present Situation and Prospects of Seawater Desalination Industry in China

Seawater desalination industry is one of the key supported major industries of marine economy in China. There is a great potential international and domestic market of desalination industry. This paper summarized the development and current situation of seawater desalination industry in China, analyzed the current situation from the perspective of international competitiveness and discussed the prospects and development strategies. It is concluded that, great progress of desalination technology has been made, but applications fall behind; in facing of the great opportunity of huge market and challenges of international competition, it is strategically needed to improve the industrial structure to form economies of scale, exploit applications and promote international cooperation with overseas projects.

Modelling clogging dynamism within dual-media pre-treatment rapid filters in seawater desalination

The dual-media rapid filtration is a popular pre-treatment technology in seawater desalination industry. However, it is still difficult for operators to optimize both the filtration and backwashing processes, particularly during the rapid filtering of moderate and high turbid (MHT) influents, due to the lack of a good understanding of the clogging dynamism incurred during operations. In this study, we attempt to model the incurred clogging dynamism via both experimental and computational means. For the former, experimental filtering of MHT influents was carried out within a lab-scale dual-media rapid pressure filter under varying experimental conditions. Concurrently, dimensionless analysis of the particle removal constant (RC) parameter was performed by considering the initial influent conditions and media characteristics. Good agreement was achieved between the predicted values from the dimensionless formulation of RC and the respective experimental values, which renders the likelihood of employing the formulation to improve the design of pre-treatment rapid filters for filtering MHT influents. Lastly, we attempt to model the clogging dynamism with the homogenization upscaling approach, by computationally resolving both the macroscale and microscale hydraulic gradient under clean and increasing clogging filter condition respectively to approximate the total clogging hydraulic gradient (CHG). Good agreement between the computational and semi-empirical values was achieved for the clean filter condition. Developing the solver in an open-source Open Field Operation and Manipulation (OpenFOAM) CFD software to investigate the particles’ interactions with a singular collector grain for approximating the microscale CHG is currently in progress.

Membrane Distillation and Reverse Electrodialysis for Near-Zero Liquid Discharge and low energy seawater desalination

With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in membrane materials, modules and process design, currently shows an overall energy consumption of 3–4kWh per m3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1m3 of potable water from 2m3 of seawater (50% recovery factor) is 1.1kWh. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1M NaCl RO retentate fed at 40–50°C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transmembrane flux in the range of 1.2–2.4kg/m2h. The performance of RE stack fed with DCMD brine (4–5.4M) and seawater (0.5M) was investigated at different temperatures (10–45°C) and flow velocities (0.7–1.1cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3V and a gross power density of 0.9–2.4W/mMP2 (membrane pair). In general, optimization is required to find best operating conditions for the proposed system.

Prospects of environmental governance in addressing sustainability challenges of seawater desalination industry in the Arabian Gulf

Abstract The hyper-arid climate of the Arabian Gulf makes it an excessively water-deficient region. Ironically, the Gulf States count among the few places with the highest per capita water consumption and low tariff. Since a few decades ago, seawater desalination has been the most reliable source of portable water in the Gulf. Recently, many critical scholars raise concerns about the rising levels of brine discharge, effects of water intake and outfall systems infrastructure, plants’ high energy consumption and fragmented regulatory and policy frameworks. In this study, we explore the potentials of environmental governance in addressing sustainability risks of seawater desalination projects. The DPSIR model and the Earth system governance framework guided and supported our analysis of several multidimensional issues that underlie the characteristics of this industry. Thus, we identified 29 cause and effect factors as well as nine environmental governance intervention strategies. The study suggests that the industry's network of stakeholders can develop good ideas for fostering sustainability by using innovative tools such as hackathon—an interdisciplinary, participatory, solution-oriented, and consensus building platform. Finally, this study enjoins policymakers, businesses, and scientists to embrace more transparent, practical and holistic ideas in designing, executing and assessing technological innovations and interventions in national and regional water security initiatives.

Nanofiltration technology in water treatment and reuse: applications and costs.

Nanofiltration (NF) is a relatively recent development in membrane technology with characteristics that fall between ultrafiltration and reverse osmosis (RO). While RO membranes dominate the seawater desalination industry, NF is employed in a variety of water and wastewater treatment and industrial applications for the selective removal of ions and organic substances, as well as certain niche seawater desalination applications. The purpose of this study was to review the application of NF membranes in the water and wastewater industry including water softening and color removal, industrial wastewater treatment, water reuse, and desalination. Basic economic analyses were also performed to compare the profitability of using NF membranes over alternative processes. Although any detailed cost estimation is hampered by some uncertainty (e.g. applicability of estimation methods to large-scale systems, labor costs in different areas of the world), NF was found to be a cost-effective technology for certain investigated applications. The selection of NF over other treatment technologies, however, is dependent on several factors including pretreatment requirements, influent water quality, treatment facility capacity, and treatment goals.

A review on energy consumption of desalination processes

The technologies that are used mainly in the seawater desalination industry are reviewed and evaluated in this article. The utilization principles, applications, and problems of these processes are summarized and discussed. The desalination methods are compared with each other for performance ratio (PR), gain output ratio (GOR), unit energy consumption (kWh/m3), or unit operating cost ($/m3) and afterward the preferred method is identified.