Environmental consequences of Caspian Sea desalination and water transfer to the central plateau of Iran

The method of adaptation of the ROUK laboratory module for conducting experimental studies on the desalination of the waters of the Black Sea is presented. The paper highlights the issues of setting the main research objectives, forming a goal and studying the technological equipment of a ready-made laboratory module with artificial seawater modeling, followed by studying and determining the necessary parameters of the reverse osmosis technological process in terms of pressure and flow of desalinated water, as well as the ratio of the obtained permeates and concentrates with different initial compositions of desalinated water to achieve the required quality indicators.

Enhancing energy hub efficiency through advanced modelling and optimization techniques: A case study on micro-refinery output products and parking lot integration

Brackish and seawater pretreatment processes: A systematic literature review

Electrodialysis desalination: Borophene membrane for ion separation using non-equilibrium molecular dynamics

Desalination of sea and geothermal water on commercial membranes using pervaporation

Access to fresh water is a major human right as mankind existence depends on it. The balance between fresh water supply and actual water demand for agricultural purposes (irrigation) relies on the availability of fresh water in the underground aquifers or surface water resources. Water resources are under great pressure due to the high demand for irrigation to sustain crop productivity and cover domestic use as a result of demographic growth. Desalination of sea or brackish water is one of the solutions to provide water for irrigation in remote areas of limited freshwater reserves. In such areas, if desalination is powered by renewable energy sources, then it can become a lot more sustainable. This paper presents the development of an innovative computational tool for the optimal (economically and technically) design of seawater reverse osmosis desalination systems for sustainable water production for crop irrigation. In order to further reduce the cost of water produced, an energy management and control system was also designed and included in the computational tool to ensure the optimal operation of the desalination plant. This system allows the seawater reverse osmosis unit to operate at variable load and determines its optimal operation point using computational intelligence techniques based on fuzzy cognitive maps. According to the results, the implementation of the computational tool for the design of PV-SWRO system presents the lowest cost as compared to the system designed with the conventional methodology.

The desalination of sea and salty water is one of the alternatives in solving the problem of freshwater recourses shortage. Reverse osmosis and distillation desalination methods are widely used for industrial, household and potable water supply. Each method requires definite energy and material costs. That’s why the problem of developing and researching the most effective energy and financial desalination plants is up to date. The aim of our research is the analysis of self-sufficient hygroscopic desalination plant operation efficiency. The comparative analysis of the most popular desalination methods has been carried out. The authors describe the desalination plant components and its operation principle. The main factors that influence plant intensity are determined. The plant developed efficiency is to increase the performance due to additional steam generation on the basis of steam-gas-liquid balanced condition law. Energy effectiveness increase is reached thanks to heat energy recycling in a condenser-separator and in a fresh water coil. The authors state that one of the best ways to accelerate the hygroscopic desalination process is to increase the initial temperature of water in barbotage area. The plant developed is characterized with high energy effectiveness, low costs and high quality of fresh water obtained.

The effect of phosphonate-based antiscalant on gypsum precipitation kinetics and habit in hyper-saline solutions: An experimental and modeling approach to the planned Red Sea – Dead Sea Project

The work relates to the technique of desalination of sea and saline waters and can be used to obtain desalinated water with generation of electrical energy. The proposed technology of water desalination is implemented by an autonomous solar desalination-electric generator, containing a rectangular body, the roof of which is covered from above with photocells with a storage unit, an inclined evaporating tray is placed inside the body, dividing the body cavity into evaporation and condensation chambers, communicating with each other at the sides of the body through vertical slots at the ends of the body and the tray are an inlet manifold connected to a submersible feed pump, and a horizontal outlet slot. The bottom of the body is connected to a condensate collection tank, in which a condensate pump is placed, a condensation chamber, immersed in a reservoir, the inner surface of the ends, sides and bottom of the condensation the chamber is made with vertical and horizontal corrugations, into the grooves of which thermoelectric converters are inserted. The first and last of which with photocells are connected to the output collectors, a storage unit, feed and condensate pumps and other them as consumers of electricity.

Early biofouling detection using fluorescence-based extracellular enzyme activity

Results of modification of composite membranes intended for desalination of sea and surface water are presented. It has been shown that modifying the selective layer of the sea water desalination membranes can stabilize the membrane rejection in the case of an increase in the feed water temperature to 40°C. The modification of the membrane for surface water desalination makes it possible to increase silicon rejection to a level of 99.78% at 35°C. The new line of membrane elements with a modified composite membrane by RM Nanotekh is intended for application at desalination plants in hot regions (up to 40°C) in the first place, as well as in water treatment units at thermal power plants and regional power stations operating at a high temperature of feed water (up to 35°).

Ion exchange membranes (IEMs) have been widely employed in various water treatment processes such as electrodialysis for a desalination of sea or brackish water. Recently, they have also gained increased industrial importance in the applications to electrochemical energy conversion and storage processes such as reverse electrodialysis, fuel cells, and redox flow batteries. Their intrinsic properties such as electrical resistance and permselectivity are the key parameters dominating the electrochemical energy conversion efficiencies. The cost-effectiveness of ion-exchange membranes should also be considered for successful commercialization of the IEM process. In recent years, pore-filled IEMs (PFIEMs) in which an inert porous substrate provides excellent mechanical and chemical stabilities while a filling ionomer selectively transports ions through the membrane have been receiving great interests in the application to various separation and energy processes. In this work, we have investigated the optimum design parameters of the cost-effective PFIEMs for successful application to various IEM processes. In more detail, novel PFIEMs were successfully fabricated by combining a highly porous polymer (i.e. PTFE and PE) films and cationic polyelectrolytes with structurally stable anion-exchange sites for the applications to alkaline direct liquid fuel cells, all vanadium redox flow battery, and reverse electrodialysis. The prepared PFIEMs exhibited excellent electrochemical characteristics and stabilities and also remarkable energy conversion efficiencies have been achieved by employing them. Acknowledgments: This work was supported in part by the New & Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (20153030031720) and the Technology Innovation Program funded by the Korea government (MOTIE) (No. 10047796).

Desalination of sea or brackish water sources to provide clean water supplies has now become a feasible option around the world. Escalating global populations have caused the surge of desalination applications. Desalination processes are energy intensive which results in a significant energy portfolio and associated environmental pollution for many communities. Both electrical and heat energy required for desalination processes have been reduced significantly over the recent years. However, the energy demands are still high and are expected to grow sharply with increasing population. Desalination technologies utilize various forms of energy to produce freshwater. While the process efficiency can be reported by the first law of thermodynamic analysis, this is not a true measure of the process performance as it does not account for all losses of energy. Accordingly, the second law of thermodynamics has been more useful to evaluate the performance of desalination systems. The second law of thermodynamics (exergy analysis) accounts for the available forms of energy in the process streams and energy sources with a reference environment and identifies the major losses of exergy destruction. This aids in developing efficient desalination processes by eliminating the hidden losses. This paper elaborates on exergy analysis of desalination processes to evaluate the thermodynamic efficiency of major components and process streams and identifies suitable operating conditions to minimize exergy destruction. Well-established MSF, MED, MED-TVC, RO, solar distillation, and membrane distillation technologies were discussed with case studies to illustrate the exergy performances.

Water scarcity is one of the main challenges facing water management in Egypt. This in turn will have direct impacts on the agricultural sector which is a key sector for the socio-economic development in Egypt, and plays a significant role in the Egyptian national economy. In Egypt, water resources are limited to the Nile River, rainfall, deep groundwater, and potential desalination of sea. Climate change, rapid population growth, and economic development will significantly affect the future availability of water resources for agriculture sector, which consumes about 85% of total water resources in Egypt. Therefore, continuously monitoring of crop statutes and crop water consumption plays a vital role in water resources management in developing countries such as Egypt. Recently Remote sensing techniques provide decision makers with spatial information about crop statutes and water stress at region scale. Remote sensing techniques also have the ability to monitor large areas with saving time and cost. The main objective of this study is investigating the capabilities of satellite data in monitoring of water stress and crop statues in the central portion of Nile delta by using the water stress index (WSI). The water stress index was used to identify locations of poor irrigation in order to maximize the crop yield. The proposed model was calibrated and validated against the measured data by using 20 points of ground measurements for actual evapotranspiration (ETC) and wet evapotranspiration (ETWet). The performance of the model was measured using various evaluation criteria. Validation results showed that satellite data are capable of estimating WSI since the comparison between WSIobs and WSIest resulted in R2=0.5003. Therefore WSI can be considered as a quick, costless and moderate tool to provide farmers and decision makers with spatial information about crop statues and water stress.

Nickel hexacyanoferrate (NiHCF) is an attractive candidate intercalation host compound for grid scale sodium-ion batteries1,2 and for efficient electrochemical desalination of sea and brackish water resources.3,4 Its open-framework crystal structure and facile intercalation kinetics produce long life with high capacity retention, while achieving charge capacities between 60 to 70 mAh/g.1 However, to improve the in operando rate capability and selectivity of cation intercalation within NiHCF, and similar Prussian Blue analogues (PBAs), transport and kinetic processes must be characterized to identify rate-limiting mechanisms. In particular, a lack of clarity exists with respect to apparent diffusion that takes place during (de)-intercalation of cations. In the present work we explore this phenomenon through a combination of experimental characterization and particle-scale transport modelling. Most significantly, our preliminary results reveal that slow electronic conduction in NiHCF nanoparticle agglomerates limits apparent diffusion, rather than crystal-scale diffusion of cations themselves.We also show that experimental measurement of the apparent diffusion time scale (τ D =R 2/D app where R and D app are particle radius and the apparent diffusion coefficient) is more insightful and reliable, compared to measurements of diffusion coefficients alone.Previous research has focused on the measurement of PBA electronic conductivity σ and bulk Diffusivity D for fully dense thin films, while electron and cation transport within PBAs in the nanoparticulate formats needed for economically constrained applications (which require simultaneously high charge capacity and current density) have not been explored in detail. Prussian Blue thin films are known to have slow electronic conduction with σ≅5x10-5S/m.5 Diffusion coefficients of Na+ and Rb+ in NiHCF6 and of K+ in copper hexacyanoferrate (CuHCF)7 thin films were approximately 10-9 cm2/s using chronoamperometry,6 cyclic voltammetry,7 and impedance spectroscopy.7 Further, the coupling of cation diffusion and electron hopping inhibits isolation of these two effects using electrochemical characterization techniques.7 Presently we characterize cation diffusion rates within slurry-cast porous electrodes that contain NiHCF nanoparticles, electronically conductive carbon, and polymer binder. We use the potentiostatic intermittent titration technique (PITT) to determine the apparent diffusion time scales by fitting current/time response to closed-form expressions8 derived for porous electrodes having kinetic and diffusive transport limitations. We probed the effect of agglomeration of NiHCF nanoparticles by fabricating two types of electrodes. In particular, NiHCF powder was mixed with conductive carbon using either (1) a mortar/pestle or (2) a vortex mill with 5mm steel beads. Microscopy of cast electrodes revealed a larger agglomerate size and higher size dispersity for milled electrodes than for unmilled ones. Consequently, the milled electrode showed a significantly poorer galvanostatic rate capability and longer diffusion time scales. For both electrodes, Dapp varied with a concave-up profile with respect to the degree of intercalation (x in Na1+ x NiFe(CN)6). Transport modelling of these diffusion processes during galvanostatic (dis)charge, which predicts the spatiotemporal variation of of x within NiHCF nanoparticles, showed consistent scaling of charge utilization with C-rate. To explain the variation of diffusion coefficients with intercalant fraction, a new theoretical model is presented. Assuming facile crystal scale diffusion and interfacial kinetics, we find that Dapp varies (1) in inverse proportion with the volumetric differential capacitance Cdiff of NiHCF and (2) in proportion to the effective electronic conductivity of NiHCF nanoparticle agglomerates: D app = σ/ Cdiff . Here, Cdiff varies inversely with the slope of intercalation potential with respect to x and thus, is responsible for the concave-up variation of Dapp with x. Furthermore, electronic conductivity of dry porous NiHCF compacts was measured, based upon predicted values of Dapp , based on our theory, were consistent with measured values from PITT. These findings confirm that apparent diffusion in NiHCF is indeed limited by slow electronic conduction and motivate further studies to enhance diffusion rates and to explore selectivity. Acknowledgements: We are grateful for funding and support by the College of Engineering, UIUC and Mechanical Science and Engineering Department at UIUC References S. V. . Wessells, C. D.; Peddada and Y. Huggins, R. A.; Cui, Nano Lett., 11, 5421–5425 (2011).M. Pasta, C. D. Wessells, R. A. Huggins, and Y. Cui, Nat. Commun., 3, 1149 (2012)K. C. Smith, Electrochim. Acta, 230, 333–341 (2017)S. Porada, A. Shrivastava, P. Bukowska, P. M. Biesheuvel, and K. C. Smith, Electrochim. Acta, 255, 369–378 (2017)A. Xidis and V. D. Neff, 138 (1991).T. Shibata and Y. Moritomo, Chem. Commun. (Camb)., 50, 12941–3 (2014)H. Kahlert, U. Retter, H. Lohse, K. Siegler, and F. Scholz, J. Phys. Chem. B, 102, 8757--8765 (1998).J. Li, F. Yang, X. Xiao, M. W. Verbrugge, and Y. T. Cheng, Electrochim. Acta, 75, 56–61 (2012).

Modification of polyamide membranes by hydrophobic molecular plugs for improved boron rejection

Electrodialysis related processes are effectively applied in desalination of sea and brackish water, waste water treatment, chemical process industry, and food and pharmaceutical industry. In this process, fundamental component is the ion exchange membrane (IEM), which allows the selective transport of ions. The evolvement of an IEM not only makes the process cleaner and energy-efficient but also recovers useful effluents that are now going to wastes. However ion-exchange membranes with better selectivity, less electrical resistance, good chemical, mechanical and thermal stability are appropriate for these processes. For the development of new IEMs, a lot of tactics have been applied in the last two decades. The intention of this paper is to briefly review synthetic aspects in the development of new ion-exchange membranes and their applications for electrodialysis related processes.

The characterization of polyvinyl chloride (PVC)-based cerium(IV) sulphate (CS) composite membrane was carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The composite membrane with 0.175 g PVC and 0.375 g CS proves good chemical, mechanical and thermal stabilities as well as ion exchange capacity. The Teorell, Meyer and Sievers (TMS) method was used to determine the electrochemical parameters such as transport number, mobility ratio and surface charge density of the membrane. The mobility ratio of various univalent electrolytes depends on the electrolyte concentration and follows the decreasing order LiCl > NaCl > KCl. This membrane may be used for treatment of food industry wastewater as well as desalination of sea and brackish waters.

Preparation of ion-exchange materials and membranes