Showing papers on "Electrodeionization published in 2017"

Development of a Resin Wafer Electrodeionization Process for Impaired Water Desalination with High Energy Efficiency and Productivity

Abstract: Use of groundwater, reclaimed water, and other impaired water sources is a critical strategy for fresh surface water conservation. Because impaired water desalination by reverse osmosis is energy-intensive, a robust ion-exchange resin wafer electrodeionization technology was developed to conserve energy during impaired water desalination. The loose ion-exchange resin beads were immobilized and molded to form a porous resin wafer material and utilized for impaired water desalination. In this study, the impaired water desalination using resin wafer electrodeionization was evaluated along with various key performance indicators, including current efficiency, energy efficiency, and productivity. Results suggest that resin wafer electrodeionization can improve energy efficiency to >35% in comparison to that of reverse osmosis (normally ∼12%) for impaired water desalination. The energy consumption of resin wafer electrodeionization was found to be 0.354–0.657 kWh/m3 with a productivity of 20.1–41.3 L h–1 m–2 (i...

Optimization of operational conditions in continuous electrodeionization method for maximizing Strontium and Cesium removal from aqueous solutions using artificial neural network

Abstract: Abstract Strontium (Sr) and Cesium (Cs) are two important nuclear fission products which are present in the radioactive wastewater resulting from nuclear power plants. They should be treated by considering environmental and economic aspects. In this study, artificial neural network (ANN) was implemented to evaluate the optimal experimental conditions in continuous electrodeionization method in order to achieve the highest removal percentage of Sr and Ce from aqueous solutions. Three control factors at three levels were tested in experiments for Sr and Cs: Feed concentration (10, 50 and 100 mg/L), flow rate (2.5, 3.75 and 5 mL/min) and voltage (5, 7.5 and 10 V). The obtained data from the experiments were used to train two ANNs. The three control factors were utilized as the inputs of ANNs and two quality responses were used as the outputs, separately (each ANN for one quality response). After training the ANNs, 1024 different control factor levels with various quality responses were predicted and finally the optimum control factor levels were obtained. Results demonstrated that the optimum levels of the control factors for maximum removing of Sr (97.6%) had an applied voltage of 10 V, a flow rate of 2.5 mL/min and a feed concentration of 10 mg/L. As for Cs (67.8%) they were 10 V, 2.55 mL/min and 50 mg/L, respectively.

Study on the influence of applied voltage and feed concentration on the performance of electrodeionization in nickel recovery from electroplating wastewater

Abstract: Wastewaters from electroplating industries are usually contaminated with nickel up to 1000 mg/L. According to environmental regulations worldwide, nickel concentration on wastewaters must be controlled to an acceptable level before being discharged to the environment. This paper offers an alternative way to develop an efficient effluent-free technology to reduce the nickel content of rinse water so that the treated water could be recycled for rinsing and subsequently to workout methodology to recover nickel by electrodeionization (EDI). Electrical voltage and initial nickel concentration were varied to study the effect of the parameters. Results showed that EDI could remove nickel effectively which gives an outstanding result in terms of product quality. Nickel concentration on diluate chamber decreased up to 99% after 60 and 180 minutes for nickel concentration of 300 and 1000 mg/L, respectively. Meanwhile, the increase of electrical voltage led to faster nickel removal.

Emerging and Combined Electrochemical Methods

Abstract: Electrochemical water treatment methods offer ways to find more sustainable solutions for water treatment applications. The majority of electrochemical water treatment methods use electricity as the main reactant to conduct the treatment process. Among well-developed electrochemical water treatment methods such as electrocoagulation, electroflotation, electrodialysis, electrochemical oxidation, and reduction, there are emerging methods, which show good prerequisites for their use in industrial scale applications. These methods tend to increase further removal rates of pollutants, eliminate drawbacks, and extend the applicability of existing electrochemical water treatment methods as well as improve cost-efficiency. The following emerging and combined electrochemical methods will be discussed in this chapter: electrodeionization, capacitive deionization, electro-Fenton, microbial fuel cell treatment, photo- and sonoelectrocatalyses. Electrodeionization combines two desalination processes into one, which are electrodialysis and ion exchange, and as a result provides even deeper demineralization rates. Capacitive deionization is an energy-efficient method allowing simultaneous water desalination and recuperation of electric energy. Electro-Fenton allows in situ generation of catalysts, thus reducing the sludge formation. Microbial fuel cells, along with the water treatment, allow recovery of electrical energy, thus reducing maintenance cost required for this method. Photoelectrocatalysis provides better removal efficiencies compared to singular photocatalysis because of the enhanced charge carrier separation and suppression of electron–hole recombination in electric field. Sonoelectrocatalysis improves the mass transfer of reactive species, inhibits polarization of electrodes, and contributes to hydroxyl radical generation, thereby enhancing the efficiency of the treatment comparing to the singular electrochemical oxidation.

Influence of ion exchange resin on the performance of continuous electrodeionization (CEDI) treating low-level radioactive wastewater

Abstract: With the fast development of nuclear power, low-level radioactive wastewater (LLRW) treatment will meet more severe requirements. Continuous electrodeionization (CEDI) is a novel technology to trea...

Optimization of the electrodeionization process: comparison of different resin bed configurations

Abstract: Optimization of the EDI resin bed poses a serious challenge for the design. This research work deals with this optimization problem. It is based on the comparison of five different configurations (homogenous/mixed, cationic, anionic, inert and two layers ordered bipolar beds). The performance of the EDI systems was evaluated in terms of removal efficiency (RE), current efficiency (CE), power consumption (P) and was evaluated by the comparison of I–V curves. The ionic mobility was also calculated using Nernst–Planck equation. Our results are summarized by this efficiency order: two layers ordered bipolar bed > homogenous mixed bed > cationic bed > anionic bed > inert bed. This is particularly due to the bipolar effect between resin layers and the polarization decrease at the cation-exchange membrane and anion-exchange membrane surfaces.

A sustainable and efficient process for the preparation of polyethylene–polystyrene interpolymer based anion exchange membranes by in situ chloromethylation for electrodialytic applications

Abstract: The present article describes the preparation of efficient and stable anion exchange membranes (AEMs) from the inter-polymer of polyethylene and polystyrene-co-polydivinylbenzene. The chloromethylated moiety in the interpolymer film was incorporated by an in situ Friedel–Crafts reaction followed by quaternization with trimethylamine. This process dispensed the direct use of hazardous and carcinogenic chloromethyl ether which is required for functionalization of interpolymer films. The effects of mole ratio of reactants during the electrophilic substitution reaction were investigated and the degree of chloromethylation was optimized. The anion exchange membrane was characterized by ATR-IR spectroscopy, thermogravimetric analysis, stress–strain properties, ion-exchange capacity and water uptake. The electrochemical properties such as the membrane resistance, ionic conductivity and transport number were also determined. The oxidative stability of the membrane was verified by treatment with 3% Fenton's reagent at room temperature. The performance of the membrane in terms of water desalination by electrodialysis and ultrapure water production by the electrodeionization process was evaluated and compared with those of polyethylene–poly-4-methylstyrene interpolymer based membranes and two other commercial membranes (Ionsep and Fujifilm).

Enhanced production of water for haemodialysis using electrodeionization

Abstract: Water for haemodialysis (WFH), which is manufactured on-site in haemodialysis hospitals, is indispensable for haemodialysis therapy. Water treatment systems for manufacturing WFH primarily consist of membrane separation technologies: reverse osmosis (for chemical contaminants) and ultrafiltration (for microbial contaminants). To further improve the quality of WFH, we successfully apply adsorption technology, namely electrodeionization (EDI), after reverse osmosis to remove additional chemical contaminants and microbial contaminants from WFH. When the DC current was supplied to the EDI system, we found that single-stranded bacterial DNA could also be removed by the EDI, as well as viable bacteria and endotoxins.

Combined radioactive wastewater treatment device

Abstract: The invention relates to a combined radioactive wastewater treatment device, comprising a selective inorganic adsorption module; an ultrafiltration membrane pretreatment module, comprising an ultrafiltration water inlet tank, an ultrafiltration feed pump, a self-cleaning filter, an ultrafiltration membrane assembly and an ultrafiltration middle water tank which are connected in sequence by pipelines; a reverse osmosis treatment module, comprising a reverse osmosis feed pump, an ultraviolet sterilizing lamp, a security filter, a first-stage reverse osmosis assembly and a second-stage reverse osmosis assembly which are connected in sequence by pipelines; a continuous electrodeionization fine treatment module, comprising a first-stage continuous electrodeionization device and a water production tank. According to the combined radioactive wastewater treatment device, a combination of multiple processes is adopted, process selection can be performed according to the characters of inlet water, and resin type secondary wastes are not generated by the treatment device; the treatment device is movable, so that the treatment device can be not fixedly arranged at one place, thus improving the radioactive wastewater treatment capacity of a nuclear power plant in a nuclear emergency state; the whole treatment device has the advantages of small size, low energy consumption, high decontamination coefficient and convenience in maintenance and change.

Transport phenomena in the electrodeionization of cesium from AMP-PAN

Abstract: Electrodeionization (EDI) of cesium from cesium-sorbed ammonium molybdophosphate-polyacrylonitrile (AMP-PAN) was investigated by passing eluant through the packed bed of ion-exchange resin in an electrodialysis cell. The deionized cesium from the packed bed was recovered in catholyte by migration and in the eluant by convection. Recovery percentage of Cs by migration increased while the recovery by convection decreased with increase in current density from 20 to 40 mA/cm2. Increased eluant concentration resulted in low migration percentage of cesium. Increased catholyte concentration had a negligible effect on total recovery. Apparent diffusion coefficients evaluated using the Nernst–Plank relation increased with increase in current density and catholyte concentration while a decreasing trend was observed with increase in eluant concentration.

Energy generation from pollutants

Abstract: The present invention relates to a system of Electrodeionization (EDI)-Solid Oxide Fuel Cells (SOFC) and anaerobic treatment for energy recovery for the treatment of carbonaceous and nitrogenous pollutants. Anaerobic microorganism community metabolizes complicated carbonaceous and nitrogenous pollutants to biogas and digestate. Biogas is directly collected, and NH4+ is concentrated and converted to NH3 gas accompanied with by-product H2 in the cathode of EDI. Then, biogas, hydrogen and ammonia generated are fed into SOFC to generate power with high energy efficiency.

Ultrapure water production system and production method thereof

Abstract: The first improvement of the invention relates to an ultrapure water production method. The method comprises the following steps: a), performing first filtering on pretreated raw water; and using a security filter to perform the first filtering; b), performing reverse osmosis filtering on the raw water subjected to the first filtering; c), performing electrodeionization treatment on pure water subjected to the reverse osmosis filtering; and d), performing electrical resistivity detection on fresh water subjected to the electrodeionization treatment, comparing a detection value with a preset value, and ensuring that ultrapure water is obtained if the detection value reaches the standard; and repeating the step c if the detection value does not reach the standard. The ultrapure water production method is less in detection items, the ultrapure water production efficiency is high, and the invention further provides a corresponding ultrapure water production system.

Characterization of Ion Exchange Material Behavior under Pressure Simulating Electro-Membrane Cell Conditions

Abstract: Goal of this work was to measure dimensional changes of ion-exchange membranes and resins used in electrodialysis (ED) or electrodeionization (EDI) devices under the applied pressure and temperatures up to 60 °C in order to describe their behavior in real conditions of these processes. Regarding ion exchange resins, measurements of their compressibility were carried out with samples of gel strongly basic and strongly acidic pure resins, their mixture and macroporous strongly acidic resin. In case of ion exchange membranes, their thickness changes under the influence of pressure and temperature were measured and long-term experiments were performed with the maximal applied pressure. To obtain a complete view, ED spacer frame foil properties were also examined in longterm experiments. For each experiment, the unique work methodology and measurement apparatus was proposed. It was found that each resin exhibited specific behavior under applied pressure and temperature. Furthermore, the important impact of temperature changes on ion exchange membranes and ED spacer foils was observed, and then, it was examined under the conditions of pressure load similar to that in real ED device. This work confirms that the research of mechanical properties of ion exchange materials has a great importance, mainly if it simulates real conditions in industrial ED and EDI modules. It can help in designing new or improved module components taking into account expected temperature or pressure changes of ion exchange materials.

Process for the preparation of pharmaceutically usable waters, in particular waters for injection and device for carrying out the process

Abstract: The invention relates to a process for the preparation of phytopharmaceutical waters (31), in particular water for injection (WFI). Here, water is drinking quality, which is hereafter referred to as feed water (30), at least one reverse osmosis (10) and at least one ultrafiltration (20) subjected to treat the feed water (30). Here, for the ultrafiltration membrane (20) used is a ceramic membrane (21) and the module in which the ultra-filtration (20) takes place, it is permanently acted upon by ozone. The invention now proposes that after the at least one reverse osmosis (10) the water of an electrodeionization (11) is subjected. Furthermore, the invention relates to a device for carrying out the method described above for the preparation of phytopharmaceutical waters (31), the invention provides that at least one reverse osmosis device (10) and at least one ultrafiltration device (20) and a Elektrodeionisationseinrichtung (11) are provided and that the membrane of the ultrafiltration device (20) is acted upon a ceramic membrane (21) and the ultrafiltration device (20) with ozone (Fig.1).

Dialysate free artificial kidney device

Abstract: A device and method are described for the treatment of blood, which device may be used in conjunction with or in place of a failed Kidney. The device includes an ultrafiltration unit to remove proteins, red and white blood cells and other high molecular weight components, a nanofiltration unit to remove glucose, at least one electrodeionization unit to transport ions from the blood stream, and a reverse osmosis unit to modulate the flow of water, to both the blood and urine streams. In one embodiment, a specialized electrodeionization unit is provided having multiple chambers defining multiple dilute fluid channels, each channel filled with an ion specific resin wafer, and electrodes at the extremity of the device and proximate each of the resin filled dilute channels. By selective application of voltages to these electrodes, the ion transport functionality of a given dilute channel can be turned on or off.

Purified water recycling system for glass coating film production line

Abstract: The invention discloses a purified water recycling system for a glass coating film production line, relating to the technical field of production of glass coating films The purified water recycling system comprises a tap water inlet pump, a bag type filter, a quartz sand filter, an activated carbon filter, an ultrafiltration membrane filter, a first-stage reverse osmosis membrane filter, a second-stage reverse osmosis membrane filter, an EDI electrodeionization device, an ultraviolet sterilization device, a purified water storage tank, a first collection tank, a second collection tank and a third collection tank According to the purified water recycling system, water resources of all stages are reasonably utilized, the consumption of water is saved by two thirds, the water resources are saved, and the production cost is greatly lowered

EDI Ultra-pure water production system using electrical de-ionization

Abstract: An ultra-pure water production system using electrodeionization (EDI) is disclosed. The ultra-pure water producing system using EDI comprises: a pure water generation module configured to filter raw water supplied from the outside to generate pure water; an EDI module configured to purify the pure water generated by the pure water generation module; a storage tank module configured to store the pure water deionized in the EDI module; an ultra-pure water generation module configured to generate ultra-pure water by filtering the pure water supplied from the storage tank module; and a dispenser module configured to discharge the ultra-pure water generated by the ultra-pure water generation module to the outside. The present invention is advantageous in that purity of the ultra-pure water may be further improved as the pure water generated by the pure water generation module is purified through the EDI module and then passes through the ultra-pure water generation module.

Hybrid Systems and Methods with Forward Osmosis and Electrodeionization Using High-Conductivity Membranes

Abstract: Fluid desalination systems that include an FO reactor and an electrodeionization reactor with improved membranes and solvents, and a method of using such systems, are provided. A fluid having a first salt concentration is directed to the FO reactor, which uses a solute to draw salt away from the fluid across a membrane into the solute, where the electrodeionization reactor is salinized solute fluid and (i) generate substantially desalinated fluid and (ii) regenerate the solute for return to the forward osmosis reactor. The electrodeionization reactor is configured to draw positive and negative ions of the solute across cationic and anionic membranes, respectively, by applying a voltage across electrodes sandwiching the cationic and anionic membranes. In some cases, the cationic and anionic membranes are porous gelled polymer electrolyte membranes, wherein a saturated solution of the salinized solute fluid is absorbed.

Automatic sewage recycling treatment system

Abstract: The invention discloses an automatic sewage recycling treatment system, comprising a central control system and a sewage disposal system, wherein the sewage disposal system comprises a sewage inlet, a grillage machine, a mud settling sump, a separating pond, a chemical dosing device, a reclaimed water tank, a bag filter, a quartz sand filter, an active carbon filter, an ultrafiltration membrane filter, a primary reverse osmosis membrane filter, a secondary reverse osmosis membrane filter, an electrodeionization (EDI) device, an ultraviolet sterilization device, a water quality detector, a pure water storage tank and a water outlet which are sequentially connected by pipelines; the pipelines are respectively provided with a delivery pump; pressure gauges are respectively installed on the bag filter, the quartz sand filter, the active carbon filter, the ultrafiltration membrane filter, the primary reverse osmosis membrane filter and the secondary reverse osmosis membrane filter; the delivery pumps and the pressure gauges are all connected with the central control system. The automatic sewage recycling treatment system realizes full-automatic sewage disposal by means of the central control system and the sewage disposal system, and has the advantages of high degree of automation, simple structure, low operation cost and good water purification effect.

Super pure water production device

Abstract: The utility model discloses an it is a super pure water production device primarily to improve the part, including mechanism's body, still including being located the inside safety filter ware of mechanism's body, preprocessor module is connected to the water inlet of safety filter ware, reverse osmosis unit one or more reverse osmosis membrane modulus spare, follow filterable water passes through the high -pressure pump entering in the safety filter ware reverse osmosis unit, the electrodeionization module, the water inlet is connected reverse osmosis unit's delivery port, resistivity detection device connects the delivery port of electrodeionization module. The utility model provides a super pure water production disposition of equipment after preprocessor module carries out the preliminary treatment to the raw water, water gets into the safety filter ware, the utility model provides an it is few that super pure water production device detects the number of times, miniaturized and quality of water super pure water production device up to standard.

Method and device for preparing supplied water of ship boiler by seawater

Abstract: The invention discloses a method and a device for preparing supplied water of a ship boiler by seawater. The method comprises the following steps of firstly, performing vacuum evaporation on seawater to obtain desalted water; deeply desalting the desalted water by an electrodeionization process, and removing Ca , Mg and other hardness ions, and Si and other weak dissociation matters, so as to obtain the supplied water which is suitable for the ship boiler. The method has the advantages that the quality of produced water is high, the carbonate and sulfate scaling of the boiler is reduced, the silicate scaling is obviously reduced, and the service life of the boiler is prolonged; the operation is simple and convenient, and the automation degree is high; the equipment is compact, and the occupation space is small; the waste heat of a ship engine is fully utilized, and the water treatment cost is low; the reliance of ship and marine platforms on the land water supply is decreased, and the good economic and social benefits are obtained.

Nitric phosphate fertilizer production wastewater treatment system and nitric phosphate fertilizer production wastewater treatment method

Abstract: The invention relates to a nitric phosphate fertilizer production wastewater treatment system and a nitric phosphate fertilizer production wastewater treatment method. The a nitric phosphate fertilizer production wastewater treatment system comprises: an ozone oxidation device; a sedimentation tank; a multi-medium filter; a weak acid cation softening bed for carrying out weak acid cation softening treatment on clear water; a strong acid cation softening bed for carrying out strong acid cation softening treatment on the clear water being subjected to the weak acid cation softening treatment so as to obtain softened water; an electrodialysis device for carrying out electrodialysis treatment on the softened water to obtain first concentrated water and first fresh water; a first-stage reverse osmosis device for carrying out first-stage reverse osmosis treatment on the first fresh water to obtain second concentrated water and second fresh water; a second-stage reverse osmosis device for carrying out second-stage reverse osmosis treatment on the second fresh water to obtain third concentrated water and third fresh water; and an electrodeionization device for carrying out electrodeionization treatment on the third fresh water to obtain fourth concentrated water and recovered water. With the nitric phosphate fertilizer production wastewater treatment system of the present invention, the nitric phosphate fertilizer production wastewater can be recycled.