Multi-effect Distillation Research Articles

Comparative analysis of multi-effect distillation coupled with solar energy and combined cycle power plant

Comparative analysis of multi-effect distillation coupled with solar energy and combined cycle power plant

Fouling on aluminum-brass and titanium tube surface in environment of low-temperature multi-effect distillation for desalination

Fouling on aluminum-brass and titanium tube surface in environment of low-temperature multi-effect distillation for desalination

Behavior of calcium carbonate growth during low-temperature multi-effect distillation seawater desalination

Behavior of calcium carbonate growth during low-temperature multi-effect distillation seawater desalination

A Sustainable Polygeneration System for a Residential Building

In line with the decarbonization of the domestic sector to meet the 2050 climate neutrality targets, this paper describes the energy, economic, and environmental analysis of a set of different novel configurations of polygeneration installations to provide electricity, air conditioning, domestic hot water, and desalinated water for a building of 80 dwellings. All arrangements were designed to cover 100% of the five demands required in the building with renewable energy only, from photovoltaic (PV) and photovoltaic-thermal (PVT) panels and biomass backup boilers (BB). Electricity can be sold to or purchased from the grid without electrical storage with batteries. Additional electricity generation with thermoelectric generators (TEG) coupled to the PVTs, and the BB was explicitly analyzed. The choice of electrically or thermally activated technologies (heat pump, HP/single-effect absorption chiller, SEAC for cooling and multi-effect distillation, MED/reverse osmosis, RO for desalination) created four configurations from the basic structure based on solar and biomass sources. Thus, the paper has studied four designs in detail and applied them to three case studies corresponding to different locations in Spain. They were modeled with TRNSYS and included specific models for desalination technologies. Both structures provide important energy and CO2 savings concerning the conventional supply of the building demands. The novel life-cycle analysis approach further increases the lifetime CO2 savings for all configurations as well. The electric option (the combination of HP and RO for cooling and desalting) was, by far, the most attractive solution in terms of liability and lower investment required in the three case studies.

Natural gas‐fueled multigeneration for reducing environmental effects of brine and increasing product diversity: Thermodynamic and economic analyses

AbstractWater scarcity threatens human life and it is likely to be a main concern in the next century. In this work, a novel multigeneration system (MGS) is introduced and assessed with energy, exergy, and economic analyses. This MGS includes a gas cycle, multieffect distillation, an absorption refrigeration cycle, a heat recovery steam generator, and electrodialysis. Electrodialysis is integrated into this configuration to produce sodium hydroxide and hydrogen chloride from brine to prevent its release to the environment with harmful impacts. The other products are electricity, cooling, and demineralized water. For the evaluation of the proposed system, one computer code is provided in engineering equation solver software. For physical properties calculation, the library of this software is used. The MGS produces 614.7 GWh of electrical energy, 87.44 GWh of cooling, 12.47 million m3 of demineralized water, and 0.092 and 0.084 billion kg of sodium hydroxide and hydrogen chloride over a year. Energy and exergy evaluations demonstrate that the MGS energy and exergy efficiencies are 31.3% and 18.7%, respectively. The highest and lowest value of exergy destruction rate is associated with the combustion chamber and pump, respectively. The economic evaluation indicates that the net present value of this proposed system is 3.8 billion US$, while the internal rate of return and payback period, respectively, are 0.49 and 2.1 years.

Mega-scale desalination efficacy (Reverse Osmosis, Electrodialysis, Membrane Distillation, MED, MSF) during COVID-19: Evidence from salinity, pretreatment methods, temperature of operation

The unprecedented situation of the COVID-19 pandemic heavily polluted water bodies whereas the presence of SARS-CoV-2, even in treated wastewater in every corner of the world is reported. The main aim of the present study is to show the effectiveness and feasibility of some well-known desalination technologies which are reverse osmosis (RO), Electrodialysis (ED), Membrane Distillation (MD), multi effect distillation (MED), and multi stage flashing (MSF) during the COVID-19 pandemic. Systems’ effectiveness against the novel coronavirus based on three parameters of nasopharynx/nasal saline-irrigation, temperature of operation and pretreatment methods are evaluated. First, based on previous clinical studies, it showed that using saline solution (hypertonic saline >0.9% concentration) for gargling/irrigating of nasal/nasopharynx/throat results in reducing and replication of the viral in patients, subsequently the feed water of desalination plants which has concentration higher than 3.5% (35000ppm) is preventive against the SARS-CoV-2 virus. Second, the temperature operation of thermally-driven desalination; MSF and MED (70-120°C) and MD (55–85°C) is high enough to inhibit the contamination of plant structure and viral survival in feed water. The third factor is utilizing various pretreatment process such as chlorination, filtration, thermal/precipitation softening, ultrafiltration (mostly for RO, but also for MD, MED and MSF), which are powerful treatment methods against biologically-contaminated feed water particularly the SARS-CoV-2. Eventually, it can be concluded that large-scale desalination plants during COVID-19 and similar situation are completely reliable for providing safe drinking water.

Design and Investigation of a Dynamic Auto-Adjusting Ejector for the MED-TVC Desalination System Driven by Solar Energy.

Ejectors have been widely used in multi-effect distillation, thermal vapor compression (MED-TVC) desalination systems due to their simple structures and low energy consumption. However, traditional fixed geometry ejectors fail to operate under unstable working conditions driven by solar energy. Herein, a dynamic auto-adjusting ejector, equipped with a needle at the nozzle throat, is proposed to improve the ejector's performance under changeable operating conditions. A two-dimensional computational fluid dynamics (CFD) model is built to analyze the performance and flow field of the ejector. It is found that the achievable entrainment ratio gradually increases as the needle approaches the nozzle, and the entrainment ratio of the ejector is relatively stable, varying slightly between 1.1-1.2 when the primary pressure changes from 2.5 to 4 bar. Besides, the performance comparison between the proposed ejector and the traditional ejector is studied under the same primary pressure range. The entrainment ratio of the designed ejector was 1.6 times higher than that of the conventional ejector at a primary pressure of 2.5 bar. Furthermore, the average entrainment ratio of the designed ejector is 1.14, as compared to 0.84 for the traditional ejector. Overall, the proposed auto-adjusting ejector could be potentially used in MED-TVC desalination systems under variable conditions.

Advancements in the energy-efficient brine mining technologies as a new frontier for renewable energy

The scientific community has profoundly relied on the recovery of various elements with special inference on the renewable energy-powered desalination of wastewater. Advanced developments in modern science and technology allow them to accomplish the aforesaid target using the various desalination approaches including zero discharge technology, multi-stage flash, multi-effect distillation, vapor compression, electrodialysis and membrane distillation. The recent advancements in the distribution of novel concepts over the treatment strategies allow the research community to integrate the green energy-based approaches with solar energy-efficient strategies as a renewable energy-powered desalination approach. There have been a number of advantages and disadvantages are concerned with the all the discussed approaches. However, the green-based technologies have well proven to be more preferred technology than the conventional approaches since the energy consumption, production cost and efficiency are noted to be reliable for these green-based approaches.

Technical, Environmental, and Process Safety Assessment of Acetone-Butanol-Ethanol Fermentation of Cassava Residues

The North-Colombian region has enormous potential for producing bioproducts and bioenergy from agricultural residues. Yet, scaling bioproducts and bioenergy to industrial practice requires further investigation, especially for environmental impact minimization and improved process safety. This work assesses two alternatives for valorizing cassava residues via acetone, butanol, and ethanol (ABE) fermentation. Two ABE fermentation routes are assessed. In Route 1, pretreatment and purification involve dilute-acid pretreatment and multi-effect distillation and decantation operations, while Route 2 includes steam explosion and reactive distillation. Hazard Identification and Risk Assessment (HIRA) and Waste Reduction Algorithm (WAR) were applied to assess ABE fermentation. Simulation results indicate butanol yields of 0.10–0.12 kg/kg feedstock and net energy ratio (NER) <1. Route 2 shows the highest total output of Potential Environmental Impacts (PEI) with 5.56 PEI/kg butanol. Both ABE fermentation routes obtained Fire and Explosion Damage Index (FEDI) values above 300 for acetone and ethanol recovery/purification stages. Both routes are classified as “hazardous” considering the flammability of handled substances, and their relative safety performance is remarkably similar. These results pave the way toward deploying both routes for adding value to the cassava residues in North Colombia by applying safe, efficient, and environmentally friendly transformation technologies.

An integrated system for producing electricity and fresh water from a new gas-fired power plant and a concentrated solar power plant – Case study – (Australia, Spain, South Korea, Iran)

In this study, a novel power plant configuration consisting of a concentrated solar power (CSP) plant integrated into a Brayton cycle prior to the combustion chamber was examined. In addition, at the gas turbine outlet, the coupled steam Rankine cycle (SRC) and organic Rankine cycle (ORC) were incorporated to enhance efficiency and power generation. Currently, gas-fired power plants generally use a single Brayton cycle to generate power, resulting in significant energy loss. In this study, a thermoelectric generator was employed to mitigate such energy losses. Thermoelectric generators are currently used to generate additional power, despite their higher costs. To optimize the use of the proposed system, the heat of the second gas turbine was exploited to desalinate saltwater in a multi-effect distillation (MED) unit. The proposed system is appropriate for hot coastal climates. The Brayton cycle was validated based on observational data from a power plant on the Persian Gulf shores (the Khorramshahr gas-fired power plant). Climatic parameters have a significant effect on power generation cycles. This study explores the effects of irradiance, wind speed, and ambient temperature on the proposed system in four hot coastal regions. These results could be very useful for investors and local governments in such regions. Among the most important effective and practical parameters in this study, we should mention gas turbine efficiency, inlet temperature to the organic turbine, inlet pressure to the steam turbine, and inlet temperature to the gas turbine. The exergy analysis of the system showed that the most exergy destruction is related to the combustion chamber, heliostat, solar receiver, multi-effect desalination, gas turbine 1, and thermoelectric respectively. The total production power in this system was 190.7 megawatts and the exergy loss of the entire system was reported as 47.73-megawatt hours. The economic analysis of the system showed that compressor and gas turbine 1 respectively have the highest cost rate in the proposed system, and the cost rate of electricity produced by the proposed system was $2288 per hour.The results showed that the best performance of the system is obtained in the weather conditions of Busan, Melbourne, Barcelona, and Bandar Abbas respectively.

Performance evaluation of a MED-MVC desalination plant driven by a concentrated photovoltaic thermal system and an organic Rankine cycle

In this work, a novel integration of a multi-effect distillation (MED) desalination plant driven by mechanical vapor compression and powered by a concentrated photovoltaic thermal system and an organic Rankine cycle is presented. The combined system is designed to produce fresh water at a capacity of 2500 m3/day. Three desalination configurations are studied, forward, backward and parallel cross feed. Mass, energy and exergy balances for different component of the desalination plant are elaborated and validated. The results showed that the specific electricity consumption of MED increased by 69 %, 68 % and 40 % by increasing the steam temperature from 80 to 100 °C, for the forward, backward and parallel cross feed configurations, respectively. The performance ratio decreased by 40 %, 21 % and 28 % by increasing the seawater salinity from 32,000 ppm to 47,000 ppm, for the forward, backward and parallel cross feed configurations, respectively. The results also showed that the solution for optimizing the energy consumption of the compressor by using staged compression equipped with intermediate cooling has enabled a saving of approximately 12 % in terms of electricity consumption. The levelized cost of water desalinated for optimized MED configurations ranged from 0.4 to 1.965 US$/m3. The overall results showed that the parallel cross-feed is the best configuration for desalination driven by a concentrated photovoltaic thermal system and an organic Rankine cycle. The performance of the current desalination unit has been improved compared to that of other MED technologies integrated with renewable energy sources.

Optimization of Cogeneration Power-Desalination Plants

The design of new dual-purpose thermal desalination plants is a combinatory problem because the optimal process configuration strongly depends on the desired targets of electricity and freshwater. This paper proposes a mathematical model for selecting the optimal structure, the operating conditions, and sizes of all system components of dual-purpose thermal desalination plants. Electricity is supposed to be generated by a combined-cycle heat and power plant (CCHPP) with the following candidate structures: (a) one or two gas turbines; (b) one or two additional burners in the heat recovery steam generator; (c) the presence or missing a medium-pressure steam turbine; (d) steam generation and reheating at low pressure. Freshwater is supposed to be obtained from two candidate thermal processes: and (e) a multi-effect distillation (MED) or a multi-stage flash (MSF) system. The number of effects in MED and stages in MSF are also discrete decisions. Different case studies are presented to show the applicability of the model for same cost data. The proposed model is a powerful tool in optimizing new plants (or plants under modernization) and/or improving existing plants for desired electricity generation and freshwater production. No articles addressing the optimization involving the discrete decisions mentioned above are found in the literature.

Flexibility concept in design of advanced multi-energy carrier systems driven by biogas fuel for sustainable development

In this paper, a new and comprehensive multigeneration system is developed exploiting biogas fuel. The system is examined from the perspective of energy, exergy, exergoeconomic, exergoenvironment, and safety for supplying the energy demands of large buildings such as modern hospitals located near industrial places. Multi-objective optimization is applied along with a new concept of flexibility in the system considering these five indicators. The Brayton cycle and closed Brayton cycle for power generation, dual-loop organic Rankine cycle and ejector refrigeration for power and cooling production, multi-effect distillation unit for freshwater production, carbon dioxide absorption unit by microalgae for biodiesel production, water heaters for domestic heating production, and PEM electrolyzer for hydrogen production are integrated into the devised system. From the environmental point of view, using biogas fuel and absorption of carbon dioxide leads to the best environmental efficiency in the proposed system. Moreover, the safety facet is analyzed to lower the level of damage and risk in the system. Based on the results of the optimization, the net output power, air conditioning refrigeration, freezing, and heating are reckoned at 1864, 286.6, 75.89, and 398.9 kW, and the production of freshwater, hydrogen, biodiesel, and glycerol is predicted to be 2.111, 0.00038, 0.0088, and 0.00091 kg/s, respectively. Also, the system performance ratio, unit cost of product, exergy efficiency, environmental effect of product, and overall system risk are equal to 1.828, 40.58 $/GJ, 31.11%, 6232 mPts/GJ, and 1656 $/year.

Hybrid Solar-Driven Desalination/Cooling Systems: Current Situation and Future Trend

Global warming and climate change, accompanied and assisted by rapid economic and population growth, are causing a sharp rise in cooling demands and stressing the already-limited supply of freshwater for many countries worldwide, especially those developing under hot-climate conditions. Thus, it is imperative to find solutions to meet cooling and freshwater needs without negatively affecting the environment and exacerbating the global warming problem. Solar-driven hybrid desalination/cooling technologies are a promising solution that can help in reducing greenhouse gas emissions and increasing overall efficiency and energy savings. The present study summarizes research efforts in meeting cooling and freshwater demands using the available solar resources. Various solar desalination technologies, such as multi-effect distillation (MED), single and multi-stage flash (MSF), reverse osmosis (RO), adsorption, absorption desalination, and membrane distillation (MD), and their integration with different cooling technologies, are reported. The study reported system performance indicators, such as water production rate, cooling capacity, Coefficient of Performance, and freshwater cost.

Design, modeling, and thermo-economic optimization of an innovative continuous solar-powered hybrid desalination plant integrated with latent heat thermal energy storage

Ever-increasing needs for freshwater over the globe have made scientists investigate and find out viable solutions to overcome this concern. In line with this fact, multi-objective optimization of a solar-assisted hybrid desalination plant, which encompasses multi-effect distillation with thermal vapor compression and humidification-dehumidification units, was carried out during this study. Parabolic trough solar collectors play the role of a supplier of required input energy to run this system. In addition, there is a heating and storage unit, which includes a latent heat thermal storage tank to store the excess heat gained by solar collectors and an auxiliary boiler to assist in supplying the required heat for desalination units. Design parameters such as Parabolic trough solar collectors rows, phase change materials, number of multi-effect distillation system effects, motive steam flow rate, and last effect brine temperature of multi-effect distillation system which have the greatest impact on the performance of the system are selected. The non-dominated sorting genetic algorithm was employed to conduct multi-objective optimization. According to the optimization results, the total cost rate of the system and the sustainability index is 0.548 $/s and 1.54 respectively. In addition, adding the humidification-dehumidification unit to the system contribute to producing 0.5% more fresh water and brings 0.1% extra cost.

Thermoeconomic optimization of a solar-assisted supercritical CO2 Brayton cycle, organic Rankine cycle and multi-effect distillation system

In this paper, the simulation and optimization of a combined supercritical carbon dioxide Brayton cycle, an organic Rankine cycle and multi-effect distillation system driven by solar energy have been applied for power and freshwater generation. In this cycle, the solar collector, the central receiver reflected the sun’s light by heliostats, enters the storage system and then enters the fluid stream according to the amount of heat required to initiate the cycle. The working fluid of solar receiver is a mixture of the 60% NaNO3 and 40% KNO3, supercritical carbon dioxide is working fluid of the Brayton cycle and R600 is the working fluid of the organic Rankine cycle. The innovation of this article is using power and fresh water cycle without fuel consumption (with solar system and storage tanks). The simulation of this combined cycle was carried out by engineering equation solver software and energy and exergy efficiency changes in terms of different parameters are obtained. Then, a multi objective optimization of this system considering exergy efficiency and cost of system as objective functions is performed by genetic algorithm in Matlab software. Decision variables of the whole cycles are including Compressor inlet temperature, Turbine inlet temperature, Number of MED effect, The temperature of the water fed the desalination, Evaporator pinch point, Mass flow (Critical Carbon Dioxide), Turbine inlet pressure, Compressor inlet pressure and Pressure drop. The two objective functions optimization including exergy and economic parameters of this cycle is carried out for achieving reduction of electricity generation cost and increase of the exergy efficiency. The results of this optimization showed, the maximum exergy efficiency of this combined system is 61.78% and the minimum cost of electricity production is 0.2617 $/kWh. In this regard, the multiple effect distillation system produces 530.9 KgS freshwater in 15 stages.

Multi-objective optimisation of coupling a multi-effect distillation desalination with combined cycle power plant through evolutionary algorithms

This paper deals with the application of gray wolf optimiser (GWO) based on an artificial neural network (ANN) to optimise the coupling of the Kerman combined cycle power plant (KCCPP) with multi-effect distillation desalination (MED) unit. Thermodynamic simulation of the initial power plant has been performed in the GT Pro simulator, and an extracted steam from the steam turbine was used to supply the required energy for the desalination plant. A desalination economic evaluation program called DEEP has been applied to calculate the cost of power and freshwater production. To optimise the system, a multi-objective fitness function has been defined to reach the minimum production cost and maximum performance in the dual-purpose plant. The optimisation procedure has been performed by combining an artificial neural network along with gray wolf optimiser, and the multi-objective fitness function has been predicted by a neural network at each stage of optimisation. In this analysis, the best value of 2.286 has been found for the fitness function by the gray wolf optimiser based on an artificial neural network. This fitness value has been obtained from 89.69 US$/MWh for electric power cost, 40.78% for net electric efficiency, 1.22 US$/m3 for freshwater cost, and 14 for gain output ratio. Highlight Kerman combined cycle power plant with 1912 MWe nominal power has been modelled. A multi-effect distillation desalination plant has been coupled to the power plant to supply 50,000 m3/day of freshwater. To find the optimal design of the dual-purpose plant, an artificial neural network was connected to the gray wolf optimiser algorithm. Multi-objective optimisation has been applied to increase efficiency and reduce costs in the dual-purpose plant.

Optimization and analysis of combined heat and water production system based on a coal-fired power plant

The combined heat and water (CHW) system has been studied by many scholars since it was proposed, and a project has been implemented in Shandong, China in 2021. However, there have been few studies on optimization and comparisons of cases on the heat source side of CHW. Taking a coal-fired thermal power plant as an example, through the reasonable matching of steam flows and analysis of thermal economic parameters, the effect number and heat source steam temperature of a multi-effect distillation (MED) + multi-stage flash (MSF) combined heat and water production (CHWP) system were optimized. The optimal MED heat source temperature was found to be 70 °C, and the optimal MED and MSF effect numbers were 10 and 5, respectively. Finally, the waste heat in the power plant was utilized as much as possible throughout the year. Compared with two cases of the separate heat and water production (SHWP) system, the CHWP system easily achieved better water quality and economy under the condition of almost equal exergy efficiency, and it was easier to realize than the first case of the SHWP system.

Evaluation of Solar Energy Powered Seawater Desalination Processes: A Review

Solar energy, amongst all renewable energies, has attracted inexhaustible attention all over the world as a supplier of sustainable energy. The energy requirement of major seawater desalination processes such as multistage flash (MSF), multi-effect distillation (MED) and reverse osmosis (RO) are fulfilled by burning fossil fuels, which impact the environment significantly due to the emission of greenhouse gases. The integration of solar energy systems into seawater desalination processes is an attractive and alternative solution to fossil fuels. This study aims to (i) assess the progress of solar energy systems including concentrated solar power (CSP) and photovoltaic (PV) to power both thermal and membrane seawater desalination processes including MSF, MED, and RO and (ii) evaluate the economic considerations and associated challenges with recommendations for further improvements. Thus, several studies on a different combination of seawater desalination processes of solar energy systems are reviewed and analysed concerning specific energy consumption and freshwater production cost. It is observed that although solar energy systems have the potential of reducing carbon footprint significantly, the cost of water production still favours the use of fossil fuels. Further research and development on solar energy systems are required to make their use in desalination economically viable. Alternatively, the carbon tax on the use of fossil fuels may persuade desalination industries to adopt renewable energy such as solar.

Exergy and economic analysis of a novel integration of compressed air energy storage with multi-effect distillation and multi-stage flash systems

Potable water and power shortage are major concerns for the world community. Large-scale energy storage systems (ESSs) are a suitable solution for grid-scale energy storage, among which Compressed air energy storage (CAES) is a lead technology. Hybrid CAES-Desalination was introduced in previous investigations. The system can supply power and potable water simultaneously which can be a strategic system for dry and warm climates. Multi-stage flash (MSF) and multi-effect distillation (MED) are modeled and thoroughly investigated in this paper. The CAES system's exhaust hot air is the drive power of the distillation systems. Therefore, not only the CAES system's performance is improved but also a large amount of drinkable water is generated. The compressors and turbine's dissipated heat play as the main sources in the distillation unit in charging and discharging periods, respectively. This paper has mainly focused on the exergy and economic analyses of this integration and has worked on the optimum arrangement considering exergy and economic investigation. This paper has also studied the exergy and economic analyses of the CAES system's recuperator removal. The exergy analysis declares that the majority of the exergy destruction in desalination units happens at the first stage where the heat exchange occurs. It also shows that pressure regulator, HTES, and turbine are responsible for significant shares of exergy destruction in the CAES system. The economic assessment expresses 5.1 years for the payback time of the integrated system.