Fresh Water Production Capacity Research Articles

Experimental investigation of a novel hybrid solar-geothermal desalination process

The widespread application of renewable energy, particularly in water desalination, is critical for addressing global water scarcity. This paper proposes a novel hybrid sustainable desalination method that harnesses both solar and shallow geothermal energy through evaporation and condensation processes. The desalination device under consideration uses a parabolic trough solar collector to evaporate saline water, and then transports the generated water vapor to an underground vertical conduit. The vapor cools as a result of the underground low temperature, leading to condensation and the formation of fresh water. To assess the freshwater production capacity of the proposed system, a simple lab-scale prototype was developed. The experimental prototype's findings emphasize the substantial influence of temperature and velocity of water vapor at the inlet of the buried pipe on the efficiency of freshwater production. Despite its small scale, the prototype outperforms other solar desalination methods, producing a remarkable output of 740 ml/h of fresh water under specific conditions (temperature: 53 °C, velocity: 1.4 m/s) With an estimated productivity of 90 l m−2 day−1,the present desalination prototype is more effective when compared with other earlier experimental studies of solar desalination systems such as active solar still and humidifier, dehumidifier solar systems, This research contributes to the advancement of sustainable desalination technologies, holding promise for addressing water scarcity challenges globally.

Design and multi-criteria optimization and financial assessment of an innovative combined power plant and desalination process

Geothermal power generation programs are crucial due to their long-term sustainability and environmentally friendly characteristics, particularly for potential energy-based applications in the future. Innovative designs can yield improve efficien by mitigating irreversibility, resulting in enhanced power production. Hence, this study investigates an innovative cascade thermal design model that employs geothermal resources to enhance the efficiency and output of low-temperature power generation systems, specifically through the integration of organic flash and organic Rankine cycles. Additionally, this model introduces a novel cogeneration approach by incorporating a desalination unit based on humidification-dehumidification processes, aiming to concurrently produce electricity and fresh water. Employing a combination of thermodynamic analysis and financial assessment, the system's performance was simulated and optimized in MATLAB, using the Multi-Objective Particle Swarm Optimization (MOPSO) method. A sensitivity analysis preceded the optimization, leading to the development of three distinct optimization scenarios focused on balancing power and freshwater production, maximizing exergetic efficiency and net present value, and optimizing fixed capital investment for maximum financial viability. The results highlight the second scenario as particularly effective, achieving a power generation of 254.3 kW, an exergetic efficiency of 44.84 %, and a net present value of $405,099. Conversely, the third scenario offers the best balance between freshwater production capacity (0.504 kg/s), fixed capital investment ($820,822), and a payback period of 7.12 years. This research demonstrates the potential of integrating advanced thermal models with geothermal resources for sustainable and efficient energy and freshwater production, marking a significant step forward in the development of eco-friendly cogeneration systems.

Evaluating the seawater desalination potential of an air-seawater system: through thermodynamic analysis and simulation of an indirect evaporative cooling desalination system

This paper explores the desalination potential of a non-equilibrium air-seawater system. It provides calculations for thermodynamics at three different precision levels and introduces new insights, including the concept of system exergy and reversible transitions, to enhance the understanding of the evaporative cooling and desalination processes. The results indicate that for an air-seawater system at 30 °C, which includes 1 kg of dry air at a relative humidity of 45 % and 1 kg of seawater at a concentration of 3.5 %, there is a desalination potential of 0.138 kg of water product. Furthermore, a novel desalination process that utilizes an indirect evaporative cooling (IEC) chiller is designed, modeled, and simulated to estimate its freshwater production capacity. The simulation reveals a daily water product of 0.503 m3 for specific 1 m3*s−1 of air flow rate. A comprehensive sensitivity analysis of parameters is conducted based on this model. In comparison to the thermodynamic calculations, the simulated model exhibits a reversible efficiency of 3.6 % under typical conditions, suggesting there is ample room to further exploit the desalination potential of the non-equilibrium air-seawater system. Additionally, by incorporating comments on irreversible loss analysis, several optimized strategies are proposed. Considering the exergy inherent in non-equilibrium air-seawater systems is abundant, the concept of desalination based on non-equilibrium air-seawater system holds promise to yield economic benefits and reduce carbon emissions.

Dynamic simulation of a triple-mode multi-generation system assisted by heat recovery and solar energy storage modules: Techno-economic optimization using machine learning approaches

Intelligent design and operation optimization allow energy systems to take advantage of the flexibility that multi-generation provides. This study proposes a basic solar-driven system integrated with thermal energy storage for round-the-clock energy harvesting. A modified configuration is then designed incorporating innovative multi-heat recovery approaches to increase the capacity and product diversity of the basic system. The modified system is able to cover vital urban utilities such as electricity, fresh water, cooling, and hydrogen throughout the day. To overcome the time-consuming procedure of dynamic techno-economic simulation as well as the limitation of commercial engineering equation solvers for tri-objective optimization, a deep learning approach is developed to reduce the computational complexity and improve the analysis accuracy. In this regard, the trained neural networks play an intermediary role in coupling the developed code with the MATLAB optimization toolbox. A comparison between the modified and conventional configurations indicates that implementing the multi-heat recovery approach results in a 29% increase in power generation while only increasing the overall system cost by 1.97%. From an economic perspective, the Sankey diagram depicts that the storage unit with a cost rate of 12.25 $/h accounts for 6.77% of the plant's cost rate, which enables the system to operate continuously. According to the sensitivity analysis and contour plots, the number of collectors significantly affects the total cost rate and fresh water production capacity while it has no tangible effect on the exergy efficiency.

Wood-inspired biomimetic vascular evaporator for highly efficient and stable solar steam generation in harsh environments

Solar-driven interfacial evaporation has great potential in freshwater harvesting, but it remains a huge challenge to maintain the structural stability of solar evaporator in complex and harsh environments while ensuring the water evaporation capacity. Herein, inspired by the mechanical stability and water transportation capability of vascular system in natural wood, a biomimetic vascular evaporator (BVE) was prepared by ice template induced self-assembly method for high-efficiency solar energy-driven seawater desalination and wastewater purification in harsh environments. Due to the ice crystals grow vertically and sublimate, the gel was squeezed to form a structure like vascular bundles with a uniform three-dimensional network structure and parallel vascular pores. The experimental results show that the vascular structure of BVE provides effective structural stability that 1000 times of repeated compression at 80% deformation without being destroyed. Meanwhile, integrating rapid water transportation capability, thermal positioning effect, and the reduced vaporization enthalpy endow high evaporation capacity (2.37 kg m−2 h−1, 93.11% pure water efficiency) under 1 sun irradiation. In particular, the above performance of BVE allows it to maintain a high and stable freshwater production capacity in various harsh environments, such as acid and alkali solutions, organic dyes, heavy metal wastewater, and wet soil. This work provides new insights into the rational design of the bionic photothermal evaporator, and demonstrates its potential application in long-term effective wastewater purification in harsh environments.

The feasibility of integrating three different thermal desalination units and a geothermal cycle combined with a modified Kalina cycle

To upsurge the geothermal energy-based freshwater production capacity, a novel waste heat recovery model for a geothermal cycle combined with a modified Kalina cycle is designed, investigated, and optimized in this study. The designed model relies on temperature control and efficient heat recovery capable of combining three different thermal desalination units, including multi-effect, humidification dehumidification, and separation vessel units. To ensure the possibility of integration, a coherent multi-aspect sensitivity study is conducted from thermodynamic and exergoeconomic points of view. In addition, two principal optimization scenarios are regarded and programmed in which total exergy destruction rate/output freshwater and net present value/fixed capital investment cases are included. To do optimization, a multi-objective grey wolf optimization algorithm is developed and utilized. According to the results of the sensitivity study, it is elicited that the variability of studied thermodynamic and cost-based metrics is more exposed to the variation in the inlet temperature of the separation vessel desalination. Besides, the first optimization scenario exhibits that the exergy destruction and freshwater production rates are gauged at 640.9kW and 0.619kg/s, correspondingly. Furthermore, in the second scenario, the net present value and fixed capital investment are obtained to be 164,638 $ and 225,653 $, respectively.

Water desalination plant powered by solid oxide fuel cell technology in Egypt

The unique location of Egypt makes it very promising for obtaining freshwater from the sea. After applying suitable desalination techniques integrated with solar radiation photovoltaics (PVs), freshwater can be easily produced. Integrated desalination, including solid oxide fuel cells (SOFCs), PVs, and a reverse osmosis (RO) system is proposed in this work. To demonstrate the advantages and better improve the efficiency of the integrated system, a mathematical model was established for evaluation. In this work, the model was applied in two different locations with high intensity solar radiation (El-Zafrana and El-Arish). The RO system was applied and integrated with SOFC technology then simulated and modeled using MATLAB Simulink. Results demonstrate the ability to obtain 2000 t/d freshwater production capacity with consideration of SOFC devices. The expected annual income from this plant is 750,000 USD after its sixth year of construction. In addition, the desalination process is proposed for non-stop use, over an entire day, of the used seawater. The simulation results provided in this work will help further future commercialization of such a project.

Modelling and Parametric Analysis of a Brine Treatment Unit Using a High-Temperature Heat Pump and a Vacuum Evaporator

The brine produced from desalination systems is a highly concentrated mixture, including cleansing chemicals from the water treatment processes that can possibly degrade ecosystems in discharge areas. Evaporation is a widely used method for the treatment of high salinity mixtures; however, it requires careful monitoring of the temperature and pressure in order to protect the equipment from the highly corrosive environment of the brine discharge. The proposed brine treatment system is based on the principle of vacuum evaporation with the use of a high-temperature heat pump, which is classified as “green technology”. In this study, a thermodynamic analysis of a vacuum evaporation system with a nominal freshwater production capacity of 160 L/h has been carried out, employing a numerical tool to model the flash evaporator and the heat pump. The analysis focuses on the parameters that present the most significant impact on the system’s efficiency and water production, such as the recirculation ratio, the set-point temperature of the heat pump and the pressure difference provided by the vacuum pump. The results show that, for the constant vacuum pressure difference, the water production increases with the increase in the set-point temperature and the recirculation ratio, but leads to the reduced COP of the heat pump and to an elevated specific energy consumption. Moreover, it is shown that an increased vacuum pressure difference leads to increased water production, but reduces the COP. Finally, the minimum specific energy consumption of 150 kWh/m3 of produced freshwater can be achieved for a set-point at 75 °C and vacuum of 0.21 bar, leading to a levelized cost of water about 11 €/m3.

Thermodynamic, environmental, and economic analysis of a novel power and water production system driven by gas turbine cycle

In the present study, the performance of a creative poly-generation plant generating electricity and freshwater was energetically, exegetically, economically, and environmentally analyzed. The system consists of a gas turbine as the prime mover and Kalina and humidification-dehumidification desalination units for waste heat recovery purposes. A sensitivity analysis was conducted to evaluate the influence of design parameters variation on the proposed system performance. The construction feasibility of the proposed system was assessed by utilizing Net Present Value and the payback period. According to the obtained data from the base simulation conditions, the total gained output ratio, exergetic efficiency, the total cost of products, Levelized total emission, and freshwater production capacity were obtained 0.9574, 43.05%, 20.22$/GJ, 63679kg/kW, and 10.77kg/s. The combustion chamber has the highest exergy destruction rate by 16382kW. Moreover, the sensitivity analysis revealed that an increase in the combustion temperature reduces pollutant emission and enhances the power generation rate and exergy efficiency. Regarding 2.5$/GJ and 0.085$/kWh as the fuel cost and electricity price, a total profit of 18.93$M at the end of economic book life can be obtained, with a payback time of 6.39years, demonstrating the feasibility of the plant for establishment.

A parametric study of a renewable energy based multigeneration system using PEM for hydrogen production with and without once-through MSF desalination

The importance of renewable energy compared to fossil fuels is increasing due to growing energy demand and environmental challenges. Multi-generation systems use one or more energy sources and produce several useful outputs. The present study aims at investigating and comparing solar energy based multi-generation systems with and without once-through MSF desalination unit from the thermodynamic point of view. Firstly, hydrogen, electricity, and hot water for space heating and domestic usage are produced using the system, which consists of a parabolic trough collector, an organic Rankine cycle (ORC) and a PEM electrolyzer and heat exchanger as sub-systems. The performance of the entire system is evaluated from the energetic and exergetic points of view. Various parameters affecting hydrogen production rate and efficiency values are also investigated with the thermodynamic model implemented in the Engineering Equation Solver (EES) package. The system can produce hydrogen at a mass flow rate of 20.39 kg/day. The results of the study show that the energy and exergy efficiency values of the ORC are calculated to be 16.80% and 40% while those for the overall system are determined to be 78% and 25.50%, respectively. Secondly, once-through MSF desalination unit is integrated to the system between ORC evaporator and heat exchanger producing domestic hot water in the solar cycle in order not to affect hydrogen production rate while thermodynamic values are compared. Fresh water production capacity of the system is calculated to be at a volumetric flow rate of 5.74 m3/day with 10 stages.

SABIC purchases Clariant's 50% share in Scientific Design

In this chapter, the main desalination technologies and their working principles are described. Each technology is described in detail showing how the process works. Various arrangements and designs for these techniques are presented and compared in terms of specific energy consumption, cost, freshwater production capacity, and energy efficiency. Employing some devices to increase the energy efficiency of desalination systems, like thermal vapor compression in multi-effect desalination and energy recovery in reverse osmosis is also discussed. Finally, emerging trends and directions in alternative water supply strategies are presented.

Minimum motive steam consumption on full cycle optimization with cumulative fouling consideration for MED-TVC desalination system

Multi-effect distillation (MED) desalination system always faces the inevitable fouling problem, which leads to a decrease in fresh water production and restricts its long-term efficient operation. This study focuses on improving the system's operation benefits in the full cycle. Firstly, an asymptotic model for fouling accumulation is added to a MED-TVC model, which takes into account the influence of operating conditions on the fouling rate. Subsequently, the impact of fouling accumulation on the operating state of the system is analyzed in the whole cycle, indicating the decrease of operating benefits. Finally, the full cycle operation optimization method is applied for the purpose of reducing motive steam consumption as well as meeting fresh water demand using control vector parameterization strategy. The result shows a significant reduction in motive steam consumption while maintaining fresh water production capacity, which confirms that full cycle optimization has a considerable effect on dealing with fouling problem in MED desalination systems.

Performance Analysis of a New Electricity and Freshwater Production System Based on an Integrated Gasification Combined Cycle and Multi-Effect Desalination

Integrated biomass gasification combined cycles can be advantageous for providing multiple products simultaneously. A new electricity and freshwater generation system is proposed based on the integrated gasification and gas turbine cycle as the main system, and a steam Rankine cycle and multi-effect desalination system as the waste heat recovery units. To evaluate the performance of the system, energy, exergy, and economic analyses were performed. Also, a parametric analysis was performed to assess the effects of various parameters on the system’s performance criteria. The economic feasibility of the plant was analyzed in terms of net present value. For the base case, the performance metrics are evaluated as W.net=8.347 MW, ε=46.22%, SUCP=14.07 $/GJ, and m.fw=11.7 kg/s. Among all components of the system, the combustion chamber is the greatest contributor to the exergy destruction rate, at 3250 kW. It is shown with the parametric analysis that raising the combustion temperature leads to higher electricity and freshwater production capacity. For a fuel cost of 2 $/GJ and an electricity price of 0.07 $/kWh, the total net present value at the end of plant’s lifespan is 6.547×106 $, and the payback period is 6.75 years. Thus, the plant is feasible from an economic perspective.

A novel multi-objective spiral optimization algorithm for an innovative solar/biomass-based multi-generation energy system: 3E analyses, and optimization algorithms comparison

A novel multi-generation energy system is proposed consisting of a solar gas turbine system, multi-effect seawater desalination, LNG cold energy recovery unit, and a double effect absorption chiller. In addition, different working fluids of the ORC system are examined to select the suitable working fluid in terms of global warming potential and exergy efficiency of the system. Subsequently, energy, exergy, and economic (3E) analyses are performed to comprehensively evaluate the energy system. Besides, a parametric study is conducted to assess the effect of the most influential decision variables on the proposed system. Afterward, the novel multi-objective spiral optimization (MOSPO) algorithm is introduced to minimize total cost rate of the system while maximizing the exergy efficiency as the conflicting objective functions. The proposed algorithm is developed to optimize the decision variables effectively. To ascertain the final optimum solution point, three conventional methods i.e. TOPSIS, LINMAP and Shannon’s entropy are implemented. The results revealed that exergy efficiency and total cost rate of the system at the baseline are 60.05%, and 36.75 $/h, respectively. Furthermore, the net power output of the system would be 106.5 kW in addition to 0.7703 kW heating load, 56.01 kW cooling capacity, and 35.74 kg/h fresh water production capacity. The eco-environmental assessment revealed the fact that the proposed renewable-based energy system is capable of avoiding 485 tons CO2 emissions annually, and product cost rate reduction up to 6 $/hr in comparison to coal and natural gas-based energy systems. Besides, the proposed MOSPO algorithm is compared with common optimization methods; accordingly, the conventional algorithms are selected for the comparison including non-dominated sorting genetic algorithm II (NSGA-II), the multiple objective particle swarm optimization (MOPSO) algorithm, the Pareto envelope-based selection algorithm II (PESA-II), and the strength Pareto evolutionary algorithm II (SPEA-II). The comparison results show that the proposed MOSPO algorithm is preferable according to the Taylor Diagrams showing the performance of the algorithms.

Techno-economic evaluation of a solar multi‐effect distillation/thermal vapor compression hybrid system for brine treatment and salt recovery

Desalination plants, besides freshwater, produce brine (hyper-saline by-product) and high greenhouse gases (GHGs) emissions. To address both issues, this study introduces a solar multi‐effect distillation/thermal vapor compression (SMED-TVC) hybrid system. The aim of the system is to desalinate brine (>70 g/L) and to recover freshwater and solid salt of high purity. Thus, a techno-economic model was developed to evaluate this hybrid process in two cases. Numerous sensitivity analyses have been carried out showing that the freshwater cost and the payback period decrease with an increase in (i) freshwater production capacity (from 10 m3/day to 50 m3/day) and (ii) plant life time (from 20 years to 35 years). In the second case of both freshwater and pure solid salt (NaCl) recovery, the payback period (3.98–4.47 years) is shorter than the equivalent (4.85–5.45 years) of the first case in which only freshwater is recovered. The profit from the treatment can reach up to US$1.22/m3 in the first case, while in the second case it can reach up to US$5.71/m3. The results showed that the proposed hybrid system could be a viable option for sustainable desalination brine management.

Towards a sustainable city: planning the fulfilment of urban fresh water needs of Depok in both dry and rainy seasons

Abstract Population growth over recent years in Depok has increased demand for fresh water for daily necessities. These necessities include the fresh water required by both settlements and commercial operations. The purpose of this study is to analyse the demand for fresh water created by the population growth of Depok in realising its development as a sustainable city. This study uses a quantitative approach presented through narrative analysis. In 2016, the average water requirement of Depok's population of 2,180,000 people was 3,070 litres/second in the dry season and 5,983 litres/second in the rainy season. Population projections for 2030 suggest that the population of Depok will have increased to 3,543,101 people, and that the average water requirement will then be 4,990 litres/second in the dry season and 9,724 litres/second in the rainy season. Planning alternatives proposed to meet these needs include improving the evaluation of freshwater production capacity and developing freshwater supply systems. Thus, it expected that the projected freshwater needs of Depok in 2030 can be fulfilled. This expectation can be managed and achieved through participation by society and government. However, obstacles are still faced, mainly due to more recent cultural attitudes towards using water.

Performance and economic evaluation of linear Fresnel reflector plant integrated direct contact membrane distillation system

Abstract This paper presents an investigation of a 111 MWe linear Fresnel reflector (LFR) plant integrated direct contact membrane distillation (DCMD) system. Both the technologies are synergized by using seawater as cooling fluid in the condenser, and then utilizing heated seawater from the condenser into the DCMD unit. The performance analysis of the LFR plant and DCMD unit has been conducted mainly in regard to direct normal irradiance (DNI) and feed water temperature, respectively. For the LFR plant, electricity generation increased with increasing DNI. The highest and the lowest energy production was 38.33 GWh and 14.08 GWh in June and December, respectively. The real levelized cost of energy was found to be 0.34 ¢/kWh. For DCMD unit, the evaporation efficiency increased from 39.13% to 50.01% corresponding to a feed temperature increase from 30 °C to 45 °C. The average freshwater production capacity of the DCMD unit was found to be 31,844.6 L/day with a water production cost $0.425/m3. The investigations revealed that the performance of the proposed system is quite satisfactory, and the low unit production cost of electricity and freshwater make it competitive to eradicate energy and freshwater crises.

Cathay buys Hoover, adding earth colours to existing synthetic iron oxide pigment range

In this chapter, the main desalination technologies and their working principles are described. Each technology is described in detail showing how the process works. Various arrangements and designs for these techniques are presented and compared in terms of specific energy consumption, cost, freshwater production capacity, and energy efficiency. Employing some devices to increase the energy efficiency of desalination systems, like thermal vapor compression in multi-effect desalination and energy recovery in reverse osmosis is also discussed. Finally, emerging trends and directions in alternative water supply strategies are presented.

A novel small dynamic solar thermal desalination plant with a fluid piston converter

An innovative small dynamic water desalination plant was developed and tested under laboratory conditions. The system is a combination of a heat pipe evacuated tube solar collector, conventional condenser and novel fluid piston converter. Saline water is boiled and turned into vapour in the manifold of the solar collector. A small fraction of the solar energy supplied to the plant is used to drive the fluid piston converter. Oscillations of the fluid piston periodically change the volume and pressure in the plant. For the duration of approximately half of the periodic cycle the pressure in the plant drops below the atmospheric level causing flash boiling of saline water in the manifold of the solar collector. Generated vapour is turned into fresh water in the condenser which is surrounded by a cooling jacket with saline water. The flash boiling effect improves the fresh water production capacity of the plant. Additionally, the fluid piston converter drives a pump which provides lifting of saline water from a well and pumps this through the cooling jacket of the condenser to a saline water storage tank. This tank replenishes saline water in the manifold of the solar collector. Experimental investigations demonstrated the saline water self-circulation capability of the plant and increase in the fresh water production compared to the static mode of operation. Experimental data was also used to calibrate the mathematical model of the plant. Comparison of theoretical and experimental information demonstrates that the model accurately predicts the performance of the plant. The proposed novel system with greater fresh water production capacity has a simple design and is easy to manufacture using low cost materials and therefore can be mass deployed for small scale saline water pumping and desalination across different regions with the relatively high solar radiation and shortage in the drinking water supply.

Techno-economic analysis of combined concentrating solar power and desalination plant configurations in Israel and Jordan

Combined concentrating solar power (CSP) and desalination plants represent a realistic future option for the production of electricity and fresh water for countries of the world’s sunbelt. In this paper, parabolic trough power plants for electricity production have been analysed in combination with multi-effect distillation (MED) and ultrafiltration/reverse osmosis (RO) desalination plants for two sites in Israel (Ashdod) and Jordan (Aqaba). Both RO and MED desalination plants were designed for a fresh water production capacity of 24,000 m3/d. The power block of the CSP plant was selected to meet the steam consumption of the MED plant at the design point, which led to a gross electrical power generation capacity of the power block of 42 MWel. Due to the low availability and generally high cost of coastal land, the CSP + RO plant consists of two separate units. It was assumed that the CSP plant is located at an inland location where there is land available. The RO plant is located at the sea, while the MED plant is located at the CSP site. The pumping of the seawater and the water transmission system add about 0.2 $/m3 to the levelized water costs of the CSP + MED plant compared with a plant located at the sea. Three different sizes of high temperature heat storages (0 h, 6 h and 12 h of additional full load operation of the steam turbine) were applied to find the most economic setup. At current prices for heat storage units, systems with huge heat storage capacities become economic only at high feed-in tariffs for electricity and thus high revenues. The price of the electricity generated by the CSP plant was varied to show the influence of the feed-in tariff on the water generating costs. The levelized costs of water (LCOW) strongly depend on the electricity price. Water costs in Ashdod are higher than those in Aqaba due to the lower solar irradiance. For Aqaba, LCOW of about 1 $/m3 can be realized if a feed-in tariff of about 0.24 $/kWh for electricity from renewable energy sources is established.