NL2015321B1 - Method for generating electricity with a Reversed Electro Dialysis (RED) process, and a stack, apparatus, and filler there for. - Google Patents
Method for generating electricity with a Reversed Electro Dialysis (RED) process, and a stack, apparatus, and filler there for. Download PDFInfo
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- NL2015321B1 NL2015321B1 NL2015321A NL2015321A NL2015321B1 NL 2015321 B1 NL2015321 B1 NL 2015321B1 NL 2015321 A NL2015321 A NL 2015321A NL 2015321 A NL2015321 A NL 2015321A NL 2015321 B1 NL2015321 B1 NL 2015321B1
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- 238000000034 method Methods 0.000 title claims abstract description 63
- 238000000909 electrodialysis Methods 0.000 title claims abstract description 27
- 230000008569 process Effects 0.000 title claims abstract description 26
- 239000000945 filler Substances 0.000 title abstract description 56
- 230000005611 electricity Effects 0.000 title abstract description 9
- 239000000463 material Substances 0.000 claims abstract description 77
- 239000012528 membrane Substances 0.000 claims abstract description 56
- 239000012530 fluid Substances 0.000 claims abstract description 46
- 238000005341 cation exchange Methods 0.000 claims abstract description 43
- 150000002500 ions Chemical class 0.000 claims abstract description 32
- 239000003011 anion exchange membrane Substances 0.000 claims abstract description 22
- 150000001450 anions Chemical class 0.000 claims abstract description 20
- 239000000203 mixture Substances 0.000 claims abstract description 10
- 238000005342 ion exchange Methods 0.000 claims description 37
- 238000011049 filling Methods 0.000 claims description 18
- 238000005349 anion exchange Methods 0.000 claims description 13
- 239000000126 substance Substances 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
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- 238000011109 contamination Methods 0.000 claims 1
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- 125000006850 spacer group Chemical group 0.000 description 30
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- 238000007254 oxidation reaction Methods 0.000 description 3
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/22—Fuel cells in which the fuel is based on materials comprising carbon or oxygen or hydrogen and other elements; Fuel cells in which the fuel is based on materials comprising only elements other than carbon, oxygen or hydrogen
- H01M8/227—Dialytic cells or batteries; Reverse electrodialysis cells or batteries
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
- H01M8/241—Grouping of fuel cells, e.g. stacking of fuel cells with solid or matrix-supported electrolytes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The present invention relates to a method for generating electricity with a Reversed Electro Dialysis (RED) stack by performing a reversed electro dialysis (RED) process to generate electricity, and a stack, apparatus and filler there for. The method comprising the steps of: providing a Reverse Electro Dialysis stack comprising: a number of cation exchange membranes; a number of anion exchange membranes; and a number of fluid compartments wherein a compartment is formed between an alternately placed cation exchange membrane and an anion exchange membrane; providing a compartment filler in at least some of the fluid compartments with the filler comprising a mixture of an anion and a cation exchange material; supplying a first and second fluid to adjacent compartments, wherein the first and second fluids have different electric potentials causing a transfer of ions between compartments; and generating an electrical current.
Description
Method for generating electricity with a Reversed Electro Dialysis (RED) process, and a stack, apparatus, and filler there for
The present invention relates to a method for generating electricity with a Reversed Electro Dialysis (RED) stack by performing a reversed electro dialysis (RED) process to generate electricity from two solutions with different salt concentrations.
Conventional methods for performing Reversed Electro Dialysis (RED) with a RED stack involve providing a number of ion-exchange membranes. More specifically, the stack comprises a number of alternating cation and anion exchange membranes. Adjacent membranes are separated by a spacer that is situated between two adjacent ion-exchange membranes. Spacers maintain the distance between the adjacent cation and anion exchange membranes that are stacked in an alternating pattern between a cathode and an anode. The space between the membranes is referred to as fluid compartment. In use, when generating electricity, the compartments are alternately filled with two solutions having a difference in (salt) concentration or (electro) chemical potential that causes transport of ions through the membranes from the concentrated solution to the diluted solution, wherein cations permeate through the cation exchange membrane in the direction of the cathode and anions permeate through the anion exchange membrane in the direction of the anode. Electro-neutrality of the solution in the anode compartment is maintained via oxidation at the anode and electrode-neutrality of the solution in the cathode compartment is maintained via reduction at the cathode, such that electrons can be transferred from the anode to the cathode via an external circuit, thereby enabling generating electrical power. An example of such stack is disclosed in NL 1031148.
Conventional methods for generating electricity with RED stacks suffer from (efficiency) losses, for example the membrane resistance. Also, due to imperfect membranes some salts are transported across the membranes due to diffusion in the opposite direction (e.g. cations move through the anion exchange membranes and anions move through the cation exchange membranes), and transport of water as result of osmotic forces causing mixing of the solutions without generating electrical energy. This reduces the efficiency of the electrical energy generation process. NL 1036698 discloses an open structure two-part spacer that can be used in a RED process. The different spacer parts are made of different ion exchange (membrane) material. The open structure of the spacer parts minimizes hydraulic friction and fluid resistance.
The present invention has as its objective to improve the efficiency of generating electricity from two solutions with different salt concentrations by performing a RED process with a Reverse Electro Dialysis stack.
This objective is achieved with the method performing a Reverse Electro Dialysis process with a RED stack generating electrical energy according to the invention, the method comprising the steps of: - providing a Reverse Electro Dialysis stack comprising: - a number of cation exchange membranes; - a number of anion exchange membranes; and - a number of fluid compartments wherein a compartment is formed between an alternately placed cation exchange membrane and an anion exchange membrane; - providing a compartment filler in at least some of the fluid compartments with the filler comprising a mixture of an anion and a cation exchange material; - supplying a first and second fluid to adjacent compartments, wherein the first and second fluids have different (electro)chemical potentials causing a transfer of ions between compartments; and - generating an electrical current.
The fluid compartments that are formed between the alternately placed cation exchange membranes and anion exchange membranes are filled with fluids having a different (salt) concentration. This provides a difference in (electro) chemical potential of the solution and develops a membrane potential over each membrane. The total electrical potential over a stack is the sum of the individual membrane potentials. The fluid compartments are also referred to as electrolyte compartments that in use are filled with low osmotic electrolyte solutions having low electrolyte concentrations such as river water with a relatively low osmotic pressure or value, and/or filled with a high osmotic electrolyte solutions having electrolyte solutions higher than the low osmotic electrolyte solutions, such as sea water with a relatively high osmotic pressure or value. The working electrolyte solution includes a solution of a number of positively and negatively ionized chemical components. It will be understood that high and low osmotic electrolyte solutions are relative terms and are to be considered relatively as the relative relationship of the electrolyte concentration provides the driving force for the ion transport over the stack.
To provide the fluid compartments the membranes should be provided at a mutual distance. Conventionally, this mutual distance is guarded by the use of fillers, mostly so-called spacers. According to the invention, the mutual distance between adjacent membranes is guarded by using a compartment filler comprising an amount of ion exchange material that is provided in at least some of the fluid compartments.
The provision of ion exchange material within the compartment as a filler significantly reduces the electric internal resistance against transport of ions within the compartments. By providing both anion and cation exchange materials as a filler mobility of both types of ions in a compartment is improved.
Surprisingly, the effect of the reduction of the electric internal resistance within the compartments is higher than a possible parasitic loss due to pumping power, also referred to as hydraulic friction. In fact, due to the reduction of electric internal resistance the compartments may be provided with an increased width without loss of efficiency, thereby even contributing to a reduction of hydraulic friction and loss of pumping power. This improves the overall efficiency of the electrical energy generating process with the RED stack according to the present invention. Furthermore, this provides additional freedom to design the stack according to the specific needs, for example optimizing internal resistance and hydraulic friction. A further advantageous effect of providing a compartment filler comprising an amount of ion exchange material, especially a mixture of an anion and a cation exchange material, is the reduction of polarization effects due to an effective increase in membrane surface area. In use, in conventional RED stacks the concentration difference over a membrane is significantly lower as compared to the difference between the average concentrations of adjacent compartments. This reduces the effective transport of ions through the membrane. In such conventional RED stacks this is caused by the non-optimal ion distribution over a compartment, such that concentrations in the direct vicinity of a membrane surface are higher respectively lower as the average in the fluid compartment. By providing ion exchange material as a filler in the stack according to the present invention, distribution of ions in the compartments is significantly improved, thereby reducing the polarization effect.
Furthermore, the membrane surface area of the stack according to the invention is significantly increased, thereby further optimizing the transfer of ions and electrical energy generation. This use of ion exchange material as a filler in the compartment further eliminates, or at least reduces, the so-called spacer shadow effect as no non-conducting material is blocking part of the membrane surface area, thereby disabling ion-transport through this part. Therefore, providing the ion exchange material as filler according to the present invention increases the effective membrane surface area for ion transport, thereby contributing to an increased efficiency of the overall electrical energy generation with the RED stack according to the present invention.
As mentioned, the mass transfer of ions within a stack, and particularly within a compartment, is significantly increased, as a low resistance pathway for cations and/or anions is provided due to the filler comprising ion exchanging material, particularly a mixture of an anion and a cation exchange material.
By supplying a first or second fluid to adjacent compartments, wherein the first and second fluids have a different electric potential a transfer of ions between compartments is caused. Due to the (chemical) potential difference between compartments caused by concentration differences, transport of ions through the membranes from the concentrated solution to the diluted solution is promoted. Via oxidation and reduction reactions at the anode and cathode, respectively, electroneutrality is achieved with the result that electrons are transferred from the anode to the cathode via an external circuit and electrical energy/power can be generated. For reasons that were explained earlier, the use of ion exchange material as a filler in at least some of the fluid compartments, improves the efficiency of the electrical energy generation with the RED process.
Providing the fluid compartment with a filler comprising an amount of ion exchange material has some further advantageous effects.
Surprisingly, (bio)fouling and/or scaling can be reduced and/or membranes can be regenerated efficiently. By providing the ion exchange material as a mixture of an anion and a cation exchange material, applying a potential over the RED stack allows water to dissociate in protons and hydroxyls at the interface of cation exchange material (CEM) and anion exchange material (AEM). This generated acid and base components may combat (bio)fouling and/or scaling inside the stack. In fact, this enables in situ cleaning of the stack, thereby improving the overall efficiency of the electrical energy generating process, reducing cleaning time, and reducing the risk of damaging components of the stack in conventional cleaning operations.
As a further effect, the relatively high concentration of protons and hydroxyls may regenerate the membranes by removal of multivalent ions. Such multivalent ions, for example Mg and Ca, adhere to the membrane surface stronger as compared to Na, thereby in use increasing the resistance and selectivity of the membrane. These multivalent ions can be removed by periodically providing the hydroxyls and protons using the ion exchange material of the filler within the compartment. This provides effective and efficient membrane regeneration that can be performed in situ.
Optionally, the filler according to the invention comprises an amphoteric material comprising cation exchange material and anion exchange material.
In a presently preferred embodiment according to the present invention, the ion exchange material comprises an amount of ion resin material.
Experiments have shown that the use of ion resin material is an effective means to provide ion exchange material as filler in the fluid compartment.
In a further preferred embodiment of the present invention the method comprises the step of filling the compartment with a filling ratio of at least 50%, preferably at least 70%, more preferably at least 75%, and most preferably at least 80%.
Surprisingly, when providing a substantial part of a compartment with a filler, such as at least 70%, the effect of the reduced electric internal resistance within the compartments is larger than the effect of possible increased hydraulic friction. This is achieved with the significant improvement of the mobility of ions within a compartment. Furthermore, non-optimal ion distribution over a compartment is reduced even further, thereby reducing the polarization effect. This contributes to a further improved electrical energy generation with a method according to the invention.
Preferably, the ion and cation exchange materials are provided according to an anion-cation ratio. Depending on the specific ratio transfer of cations or anions within the compartments is favored. In some applications the ratio will be about 1. In other applications, for example protons move relatively fast within the compartment, such that more anion exchange material is provided, thereby resulting in a ratio above 1, such as about 1.5.
In a presently preferred embodiment according to the invention, the compartment filler comprises an amount of beads.
By providing the ion-exchange material as a number of beads in the compartment, flexibility for designing the characteristics of the fluid compartment is improved. The beads can have different shapes, for example a spherical, granular, shredded, oval, egg and/or droplet kind of shape. It will be understood that the use of other shapes could also be envisaged in accordance with the present invention.
In one of the presently preferred embodiments according to the present invention, the compartment filler comprises wires of ion-exchange material woven into a web.
By weaving wires of anion and/or cation exchange material in a filler, such as a spacer, an optimal combination of hydrodynamic flow and the aforementioned desired properties of the ion exchange material, for example the ion exchange resin, can be achieved.
In a possible embodiment according to the present invention the compartment filler comprises a base material that is provided with an ion conducting coating. The base material can be a wire or a bead, for example, which is provided with such ion conducting coating.
The invention further also relates to a Reverse Electrode Dialysis stack for performing a Reverse Electro Dialysis process generating electrical energy, the stack comprising: - a number of cation exchange membranes; - a number of anion exchange membranes; - a number of fluid compartments wherein a compartment is formed between an alternately placed cation exchange membrane and an anion exchange membrane; and - a compartment filler that is placed in at least some of the fluid compartments, wherein the compartment filler comprises a mixture of an anion and a cation exchange material.
Such RED stack enables performing a RED process, thereby generating electrical energy, and provides the same effects and advantages as described earlier for the method.
The invention further also relates to a Reverse Electrode Dialysis apparatus for performing a Reverse Electro Dialysis process generating electrical energy, the stack comprising: - a RED stack as described earlier; and - a cathode compartment comprising a cathode and an anode compartment comprising an anode.
Such apparatus enables performing a RED process, thereby generating electrical energy, and provides the same effects and advantages as described for the method and/or the RED stack.
The invention further also relates to a filler for an ion exchange process, wherein the filler comprises an ion exchange material.
Such filler, in particular a spacer, that can be placed in a fluid compartment of an ion-exchange process provides the same effects and advantages as described for the method, RED stack and/or RED apparatus.
Conventional fillers, and in particular spacers, are made of non-ion-conducting materials and are designed with different shapes and/or weaving patterns to reduce hydraulic friction, promote turbulence, decrease or increase preferred channeling etc.
According to the invention, the filler, in particular a spacer, is preferably provided from beads and/or wires made of ion-exchange material, such as resin, (coated) ceramic, polymer or other materials and are weaved into a spacer. This provides a conductive path for respectively cations and anions. The fluid compartments become more conducting to one or more types of ions and internal resistance is reduced. As a further effect, as beads and/or wires of different types can come into contact with each other, depending on the chosen design of the spacer, and interfaces between cation exhange material and anion exchange material are provided, enabling water dissociation when applying a potential over the system. This provides cleaning and/or membrane regeneration effects that were described earlier.
The mentioned effects in relation to a filler, in particular a spacer, according to the present invention can be achieved while maintaining the desired characteristics of the filler, or in particular spacer, for example in relation to separation, low hydraulic friction, turbulence promoting etc. By changing the shape of the beads and/or wires, the diameter of the wires and/or the weave pattern, an optimal filler/spacer design can be developed for a specific application. This optimization involves several aspects, such as optimizing the hydraulic behavior, including friction, promotion of turbulence, the membrane contact with the beads and/or wires of the filler/spacer, and the surface area of the contact between anion exchange material and cation exchange material for the filler/spacer.
For example, the wires can be provided with a spherical, oval, rectangular or other appropriate shape. In case of a rectangular or semi-rectangular wire, the contact area between membranes and wires is relatively high and the contact area between wires of different types is also relatively high. Also, wires with the shape of a semi-circle can be used to enable a high contact surface with the membranes, while limiting the contact surface between individual wires, or the other way around. The use of an oval or droplet shape may reduce hydraulic friction and turbulence, while maintaining a relatively high contact area of the filler/spacer with a membrane and/or between individual wires of the spacer.
The ratio between the two different types of beads and/or wires can be chosen, as was mentioned earlier for the RED stack. Also, the diameter of the different types of wires can be chosen differently. In fact, designing the shape, weave pattern, wire thickness, wire tension and stack compression enables designing a spacer that is optimized for a specific application. Such design may influence properties such as turbulence level, ion conductivity, ratio between different material types, hydraulic friction, spacer thickness, open area, contact surface area with a membrane, interface surface area between two wires of different materials, preferential channeling of liquid flow, and ion flow and level of mixing. Optionally, the filler according to the invention comprises an amphoteric material comprising cation exchange material and anion exchange material. Alternatively, the filler according to the invention comprises only cation exchange material or only anion exchange material, or a combination of these materials according to a specific ratio as described earlier in relation to the method.
According to the invention, the filler, in particular spacer, can be provided to a RED stack, RED apparatus and used in a RED process for generating electrical energy. The filler, in particular a spacer, according to the invention can also be used for other ion exchange processes, such as electrode dialysis, electrode de-ionization, Donnan dialysis, fuel cells, diffusion dialysis, energy storage systems, and capacitive energy extraction.
Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which: - Figure 1A shows a Reverse Electro Dialysis (RED) stack according to the invention with a filler from woven ion exchange material; - Figure IB shows an alternative embodiment RED stack according to the invention with beads of ion exchange material; - Figure 2A shows an example of the parts of Figure 1 A; - Figure 2B shows alternative embodiments for bead diameter and bead type; and - Figure 3A-E shows experimental results with the RED stack according to the invention.
Reverse Electro Dialysis stack 2 (Figure 1A) is implemented in a RED apparatus 4 comprising end plate 6 with an anode 8 in anode compartment 10. Apparatus 4 further comprises end plate 12 with cathode 14 in cathode compartment 16. In use, anode 8 and cathode 14 are connected with electrical circuit 17. End plates 6, 12 are provided with electrode rinse circuit 18. Furthermore, end plates 6, 12 are provided with a number of concentrated fluid inlets 20 and outlets 22, and diluted fluid inlets 24 and outlets 26.
Between end plates 6, 12 a number of repeating cell units 28 is provided. In the illustrated embodiment, for illustrative purposes, only one cell unit 28 is shown. Individual cell unit 28 comprises cation exchange membrane 30, gasket and filler/spacer assembly 32, anion exchange membrane 34 and gasket and filler/spacer assembly 36. In the illustrated embodiment, further cation exchange membrane 38 is shown. First fluid compartment 40 is located between cation exchange membrane 30 and anion exchange membrane 34 and second fluid compartment 42 is located between anion exchange membrane 34 and cation exchange membrane 38. Spacers 32, 36 are provided from anion and cation exchange materials.
In alternative RED stack 44 that can be used in an RED apparatus 46 (Figure IB) stack 44 and apparatus 46 have the same or similar components as described in relation to stack 2 and apparatus 4 of Figure 1A. The main difference is the filling of compartments 40, 42. In RED stack 44 of apparatus 46 (Figure IB) gasket bead assembly 48 is provided with beads from an ion exchange material. In the illustrated embodiment, the beads are schematically illustrated for illustrative purposes.
Spacer 32 in RED stack 2 (Figure 2A) comprises wires of cation exchange material 50 and anion exchange material 52. Wires 50, 52 are provided in wave pattern 54. Wires 50, 52 of different types contact each other at contact surface area 56, enabling dissociating of water into hydroxyls and protons. It will be understood that other shapes for wires 50, 52 could also be envisaged in accordance with the present invention.
Wires 50, 52 and/or beads 48 can be provided from solid ion material 58 only or, alternatively, can be provided with base material 60 that is provided with conductive coating 62 (Figure 2B).
Performing a RED process involves providing compartments 40, 42 with fluids having different concentrations such that transport of ions is promoted through membranes 30, 34, 38.
This causes oxidation and reduction reactions at electrodes 8,14, enabling generation of electrical energy/power with external circuit 17 that is schematically illustrated in Figure 1A and B. Spacers or fillers from ion exchange material 32, 36, 48 provided an improved efficiency for the RED process for reasons that are explained earlier.
Experiments have been performed comparing conventional RED apparatus 4, 46 with the RED apparatus 4, 46 according to the invention with fluid compartments that are filled with ion exchange resin (Dowex Marathon MR-3) and having membranes (Neo Septa, Aston Corporation) that define the different compartments.
Figure 3A illustrates the Ohmic resistance (Ω) of a diluted compartment against the concentration in mol/liter, with triangles illustrating results with the conventional apparatus and the squares illustrating results with the apparatus according to the present invention. Results in the diluted compartment show that the Ohmic resistance is significantly lowered when using stack 2, 44 according to the present invention.
Figure 3B and 3C show the measured Voltage versus current, and the measured power versus current, respectively. The squares illustrate the results with RED stack 2, 44 according to the invention and the diamonds illustrate the results with the conventional stack. Results show an increased voltage and power such that the stack filled with the ion exchange material according to the invention outperforms the conventional stack in terms of power output.
Figures 3D and 3E illustrate the respective current and Voltage profiles of a RED process with the conventional RED stack and the RED stack 2, 44 according to the invention. Results are shown for current in time and voltage in time, respectively. Dotted lines indicate results with the conventional stack and dashed lines show the results with RED stack 2, 44 according to the present invention. The stack comprises three cell pairs with a 600 pm compartment filled with ion exchange beads or a non-conductive spacer, respectively. From the results it will be understood that the Voltage drop with the RED stack 2, 44 according to the invention is significantly lower, thereby indicating a lower internal resistance as compared to the conventional stack.
The results show the improved efficiency of RED processes when using RED stack 2, 44 in RED apparatus 4, 46 according to the present invention.
The present invention is by no means limited to the above described and preferred embodiments thereof. The rights sought are defined by the following claims, within the scope of which many modifications can be envisaged.
Clauses 1. Method for performing a Reverse Electro Dialysis (RED) process with a RED stack generating electrical energy, the method comprising the steps of: - providing a Reverse Electro Dialysis stack comprising: - a number of cation exchange membranes; - a number of anion exchange membranes; and - a number of fluid compartments wherein a compartment is formed between an alternately placed cation exchange membrane and an anion exchange membrane; - providing a compartment filler in at least some of the fluid compartments with the filler comprising a mixture of an anion and a cation exchange material; - supplying a first and second fluid to adjacent compartments, wherein the first and second fluids have different (electro)chemical potentials causing a transfer of ions between compartments; and - generating an electrical current. 2. Method according to clause 1, wherein the ion exchange material comprises an amount of ion resin material. 3. Method according to clause 1 or 2, comprising the step of filling the compartment with a filling ratio of at least 50%, preferably at least 70%, more preferably at least 75%, and most preferably at least 80%. 4. Method according to clause 1, 2 or 3, wherein providing the anion and cation exchange materials according to an anion-cation ratio. 5. Method according to clause 4, wherein the ratio is in the range of 0.25-4, preferably in the range of 0.5-2, and most preferably the ratio is about 1.5. 6. Method according to one or more of the foregoing clauses, wherein filling the compartment with the filler comprises providing an amount of beads. 7. Method according to one or more of the foregoing clauses, wherein filling the compartment with the filler comprises providing wires of ion exchange material woven into a web. 8. Method according to one or more of the foregoing clauses, wherein providing the compartment filler comprises providing a base material that is provided with an ion conducting coating. 9. Method according to one or more of the foregoing clauses, further comprising the step of cleaning the stack by providing a potential over the stack to allow water to dissociate in protons and hydroxyls. 10. Method according to clause 9, comprising the step of combatting (bio)fouling and scaling. 11. Method according to clause 9 or 10, comprising the step of regenerating the membranes. 12. Reverse Electro Dialysis stack for performing a Reverse Electro Dialysis process generating electrical energy, the stack comprising: - a number of cation exchange membranes; - a number of anion exchange membranes; - a number of fluid compartments wherein a compartment is formed between an alternately placed cation exchange membrane and an anion exchange membrane; and - a compartment filler that is placed in at least some of the fluid compartments, wherein the compartment filler comprises a mixture of an anion and a cation exchange material. 13. Reverse Electro Dialysis apparatus for performing a Reverse Electro Dialysis process with a RED stack generating electrical energy, comprising: - a Reverse Electro Dialysis stack according to clause 12; and - a cathode compartment comprising a cathode and an anode compartment comprising an anode. 14. Filler for an ion exchange process, the filler comprising an amount of ion exchange material that can be placed in at least some of the fluid compartments.
Claims (14)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL2015321A NL2015321B1 (en) | 2015-08-19 | 2015-08-19 | Method for generating electricity with a Reversed Electro Dialysis (RED) process, and a stack, apparatus, and filler there for. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL2015321A NL2015321B1 (en) | 2015-08-19 | 2015-08-19 | Method for generating electricity with a Reversed Electro Dialysis (RED) process, and a stack, apparatus, and filler there for. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NL2015321B1 true NL2015321B1 (en) | 2017-03-13 |
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| Application Number | Title | Priority Date | Filing Date |
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| NL2015321A NL2015321B1 (en) | 2015-08-19 | 2015-08-19 | Method for generating electricity with a Reversed Electro Dialysis (RED) process, and a stack, apparatus, and filler there for. |
Country Status (1)
| Country | Link |
|---|---|
| NL (1) | NL2015321B1 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4033850A (en) * | 1974-11-29 | 1977-07-05 | Yeda Research & Development Co. Ltd. | Electrodialysis device |
| WO2010104381A2 (en) * | 2009-03-11 | 2010-09-16 | Stichting Wetsus Centre Of Excellence For Sustainable Water Technology | Spacer, cell and device for an ion-exchanging process and method therefore |
| US20100326833A1 (en) * | 2007-12-17 | 2010-12-30 | Rami Messalem | Apparatus and system for deionization |
| US20140246318A1 (en) * | 2011-10-21 | 2014-09-04 | General Electric Company | Desalination system and method |
| WO2014197824A1 (en) * | 2013-06-07 | 2014-12-11 | The Board Of Trustees Of The University Of Arkansas | Reverse electrodialysis systems comprising wafer and applications thereof |
-
2015
- 2015-08-19 NL NL2015321A patent/NL2015321B1/en not_active IP Right Cessation
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4033850A (en) * | 1974-11-29 | 1977-07-05 | Yeda Research & Development Co. Ltd. | Electrodialysis device |
| US20100326833A1 (en) * | 2007-12-17 | 2010-12-30 | Rami Messalem | Apparatus and system for deionization |
| WO2010104381A2 (en) * | 2009-03-11 | 2010-09-16 | Stichting Wetsus Centre Of Excellence For Sustainable Water Technology | Spacer, cell and device for an ion-exchanging process and method therefore |
| US20140246318A1 (en) * | 2011-10-21 | 2014-09-04 | General Electric Company | Desalination system and method |
| WO2014197824A1 (en) * | 2013-06-07 | 2014-12-11 | The Board Of Trustees Of The University Of Arkansas | Reverse electrodialysis systems comprising wafer and applications thereof |
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