JPH01307410A - Electric deionizing method and apparatus - Google Patents

Abstract

PURPOSE: To efficiently execute the electric deionization of water to be treated by alternately disposing plural ion decreasing block chambers and ion thickening block chambers between an anode block chamber and a cathode block chamber. CONSTITUTION: This electric deionization apparatus has the cathode block chamber arranged at one end and the anode block chamber arranged at the other end. The ion decreasing block chambers and the ion thickening block chambers are alternately arranged between these block chambers. The ion decreasing block chamber have plural segmental block chambers which are formed by spacers and plural ribs and respectively include ion exchange solid compsns. The thicknesses of the segmental block chambers are determined by the anion permeable membranes and anion permeable membranes joined to the spacers. The respective thickening block chambers do not include the ion exchange solid compsns. The water to be treated is passed through the ion decreasing block chamber and is discharged therefrom after the water is deionized.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a novel electrodeionization device and method adapted for transporting ions in a liquid under the action of a polar electric field. Specifically, the present invention relates to an electrodeionization apparatus and method suitable for purifying aqueous liquids to produce high purity water.

PRIOR ART, PROBLEM TO BE SOLVED BY THE INVENTION The technique of purifying liquids by reducing the concentration of ions or molecules in the liquid has been an area of considerable technical interest. Many techniques have been used to purify and separate liquids, ie, to obtain concentrated pools of specific ions or molecules from a liquid mixture. The best known methods include electrodialysis, liquid chromatography, membrane filtration and ion exchange. A lesser known methodology is electrodeionization, sometimes misnamed packed cell electrodialysis. Although electrodeionization has the potential to be quite effective in removing ions from liquids, it has never been developed to the extent that it can compete with structurally and operationally better known separation techniques. This is primarily due to non-consistency in structural design accuracy and unpredictable variations introduced by currently known modes of use. This lack of precision in structural design and the unpredictability of results had been reduced to the point of relative obscurity even to practical specialists familiar with separation techniques such as the use of electrodeionization.

The first apparatus and method for treating liquids by electrodeionization was published by Kolman U.S. Pat. No. 2,689.
No. 826 and No. 2.815.320. The first of these patents transfers ions in a liquid mixture of an ion depletion chamber through a series of anion and cation membranes into a concentration chamber under the action of an electrical potential that transports preselected ions in a predetermined direction. An apparatus and method for removing a liquid into a volume of a second liquid is described. the volume of liquid being treated is depleted of ions and the second liquid is enriched with the transferred ions;
Keep it in concentrated form. The second patent describes the use of macroporous beads formed from ion exchange resins as packing material disposed between anionic or cationic membranes. The ion exchange resin acts as a conduit for ion transport and as an increased conductivity bridge for ion transfer between membranes. These patents present the main structural framework and theory of electrodeionization as a technology. The term electrodeionization refers to a process in which an ion exchange material is placed between the anion and cation membranes, and the term electrodialysis refers to a process in which an ion exchange resin is not used between the anion and cation membranes. say. Although Ollsman's technology has been available for 25 years, it has never been developed to the point of practical use. This is due in no small part to the lack of structural design precision and the inability to obtain operating mode parameters that provide reliable operation of the electrodeionization device. Examples of prior attempts to use a combination of electrodialysis and ion exchange materials to purify brine from salty waters include U.S. Pat. No. 2.947.688,
No. 3.384.568 and No. 4.165.273. Attempts to improve electrodeionization devices include U.S. Pat.
No. 713, No. 3.515.664, No. 3.562.1
No. 39, No. 3.993.517 and No. 4.284.
It is described in No. 492.

Despite the contributions represented by these patents, this prior art has not produced reliable electrodeionization devices. The problems of resin activation and membrane scale adhesion, typical of electrodeionization, have not been alleviated. These electrodeionization devices were unsuitable for seawater desalination, ie, the production of high purity water. Hard water, silica-containing water, high-salinity brine, and even water containing colloidal particles and active substances represent liquids that still cannot be consistently and reliably purified by currently known electrodeionization devices and modes of operation. .

Extensive maintenance and cleaning of these devices remains necessary;
The quality and volume of the produced liquid is variable, and the ability to consistently produce water of at least 1 megohm centimeter quality in sufficient volume remains unachieved.

U.S. Pat. No. 4,632,745 discloses an electrodeionization device that includes a depletion compartment divided into subcompartments having thicknesses of 0.3 to 4 inches and 0.05 and 0.25 inches. ing. Using this device requires only low energy and avoids channeling.
Effective ion removal from the depletion compartment is achieved.

US Pat. No. 4,634,745 may employ one or more hydraulic stages, for example two, along with two separate and independent electrical stages. Thus, one hydraulic stage includes a given number of cell pairs, for example 30, into which cell pairs water flows. A pair of cells includes a cationic membrane and an anionic membrane joined to a diluent spacer and a concentrate spacer containing an ion exchange resin. The electrical stage comprises one anodic electrode and one cathodic electrode surrounding the hydraulic stage. For low-salt feedstocks, 1
A staged stacking design is adopted, while for high salinity brine,
A two-stage stacked design is adopted. The purpose of the two-stage design is to obtain maximum salt removal in the first stage without inducing polarization, which would result in a p)I shift of the concentrate flow and be inefficient. An upward pH shift in the concentrate stream will result in scaling if calcium or magnesium ions are present in the feed water to the stack. The maximum salt removal that can occur in the first stage without polarization occurring is approximately 80%. The product water from the first stage is sent to the second stage where the remaining salts (approximately 20%) are removed to obtain a megohm product quality. The water being deionized is passed between each cell only once without changing flow direction, and the entire design is optimized for scaling in the first stage while optimizing total salt removal, membrane utilization, and energy requirements. 'Prevent wear and tear.' In comparison, electrodialysis cannot produce megohm quality water because
This is because electrodialysis is less efficient in the low salinity range and requires larger membrane area and energy. It would be desirable to provide an electrodeionization device and method that provides improved other ion removal efficiency compared to currently available devices.

SUMMARY OF THE INVENTION The present invention provides a method for producing 10 megohms for extended periods of time while avoiding significant reduction in the performance of the ion exchange resin and avoiding particle and scale formation within the electrodeionization device. The present invention provides an electrodeionization method and apparatus for producing purified water of up to centimeter quality or higher. Electrodeionization equipment has thickness,
A plurality of electrodeionization compartments of controlled width and configuration and containing ion exchange material such as beads, fibers or the like are provided. The electrodeionization ion reduction or depletion compartment in which ions are reduced from the liquid is formed from a spacer having a hollow central portion divided by ribs or the like to define sub-compartments.

Ion exchange resin beads within the subcompartment chamber bond or physically hold the cation-permeable membrane to one side and ribs of the reduction compartment, and bond or physically hold the anion-permeable membrane to the opposite side and ribs of the reduction compartment. and thereby define the subcompartments. The concentration chamber, into which ions enter from the depletion chamber, has no ion-exchange beads, and the electrodeionization device can comprise a single stage or multiple stages in series, and if desired, the process voltage can be adjusted to each stage. can be controlled independently. The ion depletion chamber and concentration chamber in each stage are located between the anode and cathode. Each stage includes at least one pair of ion depletion compartments. The water to be purified passes through at least two reduction chambers in each stage. By employing multiple passes in a single stage, the amount of water to be purified is Improved efficiency is achieved in removing ions.

EXAMPLE According to the invention, each electrodeionization stage comprises an anode and a cathode and their compartments, a series of concentration compartments, and an ion exchanger, such as a mixture of anion exchange resin and cation exchange resin. An electrodeionization device is provided that includes a series of depletion compartments containing a substance. According to the multiple pass process of the present invention, the attenuation chambers are arranged and have inlets and outlets such that the water to be purified passes through at least two attenuation compartment chambers between a given set of anodes and cathodes at each stage. , one of each stage where the water to be purified has a length equal to the combined length of the plurality of reduction compartments in each stage.
An improvement in the efficiency of ion removal is achieved compared to a process that passes through two depletion compartments. The reduced compartments are formed such that the ion exchange resin mixture is contained within separate and distinct subcompartments. Thus, each of the sub-compartments is about 4
It has a width of an inch or less, preferably about 0.5 to about 1.5 inches. The separate subcompartments are formed by securing both the anion-permeable membrane and the cation-permeable membrane to the periphery and ribs of the reduction chamber, such as by bonding. The ribs thus extend across the thickness of the reduced compartment and along its entire length such that each subcompartment is defined by a pair of ribs, an anion permeable membrane and a cation permeable membrane. In accordance with the present invention, it has been found that the thickness and width of the depletion compartment are important in achieving efficient operation of the electrodeionization device.

The solid ion exchange material disposed within the subcompartments is restrained from moving between the subcompartments by ribs and ion-permeable membranes. Representative suitable solid ion exchange materials include fibers, beads, etc. and so on. If ion exchange beads are employed, typical bead diameters are about 0.04 inches or less, preferably about 0.04 inches or less.
33 to about 0.012 inches (20 to 50 mesh)
It is.

Electrodeionization devices can include one or more stages. At each stage, an anode is located at the opposite end of the stack of depletion and enrichment compartments from which the cathode is located and an anode of the stack of depletion and enrichment compartments is located. A cathode is located at the opposite end. Each anode and cathode includes an adjacent electrode spacer and an ion permeable membrane through which an electrolyte is passed.

The remainder of each stage includes a series of alternating depletion and enrichment compartments configured as described above, wherein the liquid to be depleted of ions is transferred from the first liquid in the depletion compartment to the first liquid in the concentration compartment. The two liquids can be passed through each depletion compartment in parallel at each stage for ion removal. In each case, the liquid to be purified must pass through at least two reduction chambers in each stage. The direction of flow within the reduction compartment is not critical and may be in the same or opposite direction as the flow in adjacent compartments or enrichment compartments; if multiple stages are utilized, the flow moving through the reduction compartment in the upstream stage is Alternatively, the feed water may be directed in the opposite direction in the attenuation compartment constituting the second stage. Optionally, the electrolyte can be passed through a spacer adjacent each electrode in the electrodeionization device and removed from the electrodeionization device.

As mentioned above, it is essential that the subcompartments within the depletion compartment have controlled thickness and width to maintain high efficiency for ion depletion over long periods of time. The thickness of the subcompartments should be between about 0.25 and about 0.05 inches, preferably between about 0.06 and 0.125 inches. The width of the sub-compartment should be about 0.3 to 4 inches, preferably about 0.5 to about 1.5 inches. The length of the sub-compartment should be based on practical construction and fluid pressure drop considerations. There are no restrictions other than those dictated by the matter. Obviously, the longer the subcompartment, the greater the ion removal from the liquid therein. Generally, the subcompartment length is about 5 inches to about 70 inches. The subdivision compartment contains 100% anion exchange material, 100%
% of a cation exchange material or a mixture of both. If it is desired to remove only specific anions or cations, a suitable ion exchange material may be
0% allocated. Usually, to make a purified liquid product,
It is desirable to remove both cations and anions.

When utilizing strong acid-based resin materials such as beads, the ratio of anion exchange resin beads to cation exchange resin beads is generally about 60:40 by volume. By utilizing subdivided compartments in the reduced compartment, efficient mixing of the liquid and beads therein can be achieved, while avoiding channeling of the liquid in the reduced compartment and subdividing a portion of the volume of the reduced compartment. Compression or movement of the bead in the process can be avoided. Thus, there is an efficient exchange of ions and liquid in the depletion compartment with ions in the bead to effect removal of ions from the liquid in the depletion compartment. Furthermore, by controlling the geometry of the subdivision compartments and using multiple depletion compartments in each stage as described above, it is possible to obtain the desired liquid purity even over long periods of time compared to electrodeionization. , one stage 12 delimited by electrodes 9 and 11 comprises an inflatable bladder member 15 and an end plate 13 having an inlet 16 for fluid for inflating this bladder member 15 . End plate 13
Adjacent to the end block 17 is provided which accommodates the electrode 9 and provides the desired manifold. Electrode spacer 18
is located adjacent to the end block 17 and is provided with a screen 19 . This screen thus creates turbulence in the liquid passing through the electrode spacer. An ion permeable membrane 20 is sealed around the perimeter 21 of the electrode spacer 18 . A spacer 22 made of a flexible material is provided with a screen 24 . Spacer 22 and screen 2
4 constitutes a concentration chamber of the electrodeionization device of the present invention,
The reduced compartment structure of the present invention consists of an ion permeable membrane 26, a rigid material spacer 28, and an ion permeable membrane 30. Ion permeable membranes 26 and 30 are sealed to both sides of spacer 28 around its periphery 32 . A mixed ion exchange resin bead 34 is housed within the central space of the spacer 2'8, which includes ribs (not shown), and the liquid to be purified within the zero stage 12, held therein by the membranes 26 and 30, flows through the spacer 22.
and 28 and at least two membranes 26 and 30.
Pass through two units. The unit, including spacers 22 and 28 and membranes 26 and 30, typically has approximately 5 to 10
repeated times. Spacers 38 and screens 24 and ion exchange membranes 40 of flexible material form end concentration chambers. End plate 50 , with electrode spacer 42 disposed adjacent end plate 44 and electrode 11 , includes a flexible bladder member 52 that is inflated by fluid passing through conduit 54 . Bolts 56, 58 and 60 and a fourth bolt (not shown) extend along the entire length of device 10 and hold the components of the device in place.

Referring to FIG. 2, the fluid paths of the various compartments are illustrated. The liquid to be purified enters the inlet 62, passes through the reduction compartment 28, then passes through the second reduction compartment 28, and is withdrawn from the outlet 64. It is to be understood that liquid flow through the reduction compartment may be unidirectional at each stage. Also, the liquid can flow through more than one reduction compartment at each stage. In addition, liquid flowing out of one reduction compartment is divided into multiple streams and a second
can be passed through a set of reduced compartments. Concentrating liquid passes through inlet 66, through concentrating compartment 22, and then through outlet 6.
8 and is passed to the drain. The electrolyte is discharged from the input lower 0 through the electrode compartments 19 and 42 and through the output lower 2 to the drain.

Referring to FIG. 3, this figure shows a rigid block 44
and an electrode structure including electrode 11 is shown. The block 44 includes an electrolyte solution output lower lower 0 and an electrolyte solution output lower lower 2. Electrode 11 is provided with a connector 85, which contacts an external electrical connection 87 as shown in detail in FIG. Block 44 comprises an inlet 62 and an outlet 64 for the reduction compartment and an inlet 65 and 66 and an outlet 63 and 68 for the enrichment compartment.

Referring to FIG. 4, the electrode spacer 67 includes an electrolyte solution inlet lower 0, an electrolyte solution outlet lower 2, and a screen 90 that causes turbulence in the liquid passing therethrough.

Referring to FIG. 5, a spacer made of a flexible material;
For example, the spacer 38 is connected to the liquid inlet 66 and the liquid outlet 6.
8 and these inlets and outlets communicate the liquid into the interior of the spacer 38 where a screen 95 is placed to create a turbulent flow of the liquid. The exit 64 is
The inlet 62 allows passage of liquid to the adjacent reduction compartment.
allows the removal of liquid from the adjacent depletion compartment without mixing the purified liquid with the liquid in the concentration compartment formed in the spacer 38.

6 and 7, the structure of the reduced compartment of the present invention is shown in detail. The reduction compartment includes an ion exchange material 34 that includes a rigid spacer, such as spacer 28 and an anion permeable membrane 30 and a cation permeable membrane 26.
is housed within a subcompartment chamber formed by membranes 26 and 3o, walls 105 and ribs 99. Membranes 26 and 30 have walls 105 and ribs 9 along their lengths.
9 is sealed. Membranes 26 and 30 are also sealed around rigid spacer 28 such that individual subcompartments 98 are substantially isolated from each other. The liquid to be purified is inlet 1
The produced liquid enters the subdivision compartment 98 from 01, where it is subjected to an electrical voltage, passing the anions through the membrane 30 and the cations through the membrane 26.The resulting liquid then passes through the outlet 102 and the spacer outlet 6.
According to another aspect of the invention, the liquid to be purified is subjected to electrodeionization to remove certain contaminants such as organic substances. Can be preheated. A softener-scavenger system may be used; the softener may be a cation exchange resin and/or an anion exchange resin to remove specific ions;
Scavengers can include anion exchange resins to remove active materials that foul anion resins, such as organic materials including tannins, humic acids, fulvic acids, and lignin.

Ion exchange resins can be efficiently and easily regenerated by brine.

Any anion-permeable or cation-permeable membrane that has the strength to withstand operating pressure differentials, typically up to about 5 psi, can be used in the present invention. We would like to point out that sealing the membrane to the ribs forming the subcompartments is an improvement over prior art devices, as the strength of the assembly is thereby enhanced, allowing the use of higher operating pressures. Ionics is a typical suitable anion permeable membrane.
1 mouth C0 by CR6]-CZL-386 and AR1
Sold under the product number 03-QZL-386,
Homogeneous web-supported styrene-divinylbenzene-based resin with sulfonic acid or quaternized ammonium functionality, MC by 5ybron/1onac
-3470 and MA-3475, polyvinylidene fluoride bonded heterogeneous web-supported styrene-divinylbenzene-based resins, RAI Re5each Corporation
Heterogeneous, unsupported, sulfonated styrene and quaternized vinylbenzylamine grafts of polyethylene sheets sold under the name Ra1pore by Tokuyama Soda Co, Ltd.; Sulfone sold under the name Neoseputa by Tokuyama Soda Co, Ltd. Homogeneous web-supported styrene-divinylbenzene-based resin with acid or quaternary ammonium functionality, Asahi Industry Co, Ltd.
Examples include homogeneous web-supported styrene-divinylbenzene-based resins with sulfonic acid or quaternary ammonium groups sold under the name Ac1plex by Co., Ltd.

The examples below are illustrative of the invention and are not intended to limit it.

Example 1 This example demonstrates the improvement in separation efficiency obtained with the electrodeionization apparatus of the present invention that utilizes multiple passes through the depletion compartment in the separation stage using a single pass through the depletion compartment. This example is compared to an electrodeionization device.

Two separate laminates were assembled for comparative testing. 1st
The stack included two 26 inch long dilution cells arranged in parallel and sandwiched between one concentrate spacer and a pair of electrode spacers and electrodes (see Figure 8). Dilution cells were used in parallel to help minimize possible errors. The second stack contains four 13-inch long dilution cells arranged to obtain a two-parallel two-pass configuration (see Figure 9), and three concentrate spacers arranged to obtain parallel flow. , and the cells are bundled with electrode spacers and electrodes.

Both laminate assemblies used new membranes and new ion exchange resins. The two stacks were run simultaneously with the same liquid supply and the same power source.

Data was collected during the flight. Four series of tests were conducted and test conditions are described under each series.

Molding Test Conditions: Feed 295 μm sodium chloride; Temperature 18° C.; Power Condor 9 volt, 1 amp calquator battery charger (non-variable).

Dl refers to dilution from the 26 inch long channel.

C3 refers to the concentrate from the 26 inch long channel.

C2 and C2 refer to dilution and concentrate from the 13 inch long channel, I+, Ia; Et, El refer to current and voltage, respectively.

Water recovery is expressed as R1 and R1.

[Test I] Feed material flow rate for each laminate was 400 m1/min
The parameters that were adjusted and related in steady-state operation were as follows.

E t = 0.5 A: E I = 9.4 V: D
r = 11.2umho: CI = 580LLmh
o:R+ =67%I2=0.47A; Ez
= 11.2V; C2 = 1.5μmho;
(, a = 1220 gmho; R* = 67% C2 exceeded the water quality of Dl by 7.5x.

[Test II] The same test as Test I was conducted with the feed flow rate adjusted to 30 Gml/min, and the relevant parameters in steady-state operation were as follows.

I l = 0.73 A: El = 9.7 V.

Dr = 10.0 μmho: C+ = 60
0μmho; R, = 67% Iz = 0.043A; El = 11.4V
;C2=(1,5gmho;C2=1450
gmho ; R, = 77% C2 exceeded the water quality of Dl by 20X.

[Test nr] Feed material flow rate was 5 for each laminate.
The same test as Test I was conducted by adjusting the speed to 00 m1/min, and the parameters involved in steady operation were as follows.

I l = 1.09 A: E, = 8.7 V.

D, ==15.5μmho; Cr=600
μmho: R1 = 68% I z = 0.55A; E2 = 1.08V; D
a = 2.9 umho: Cz = 1300
umho: R2=80% Dl exceeded Dl crystalline by 5x.

[B series test] Test conditions are the same as Nijiries A test, but condo
r Using a 12 volt amp calculator battery charger (non-variable).

[Test IV] The feed flow rate to each laminate was adjusted to 500 ml/min, and the relevant parameters in steady-state operation were as follows.

1 + =1.21; El =IO, 2V; D+
= 14.0 μmho; Cr = 535 μmho
o; Rr = 68%12 = 0.640
．． E, = 13.6V: Da = 0.65
umho ; Cm = 1350 u
mho:R,=78% Dl exceeded D+ crystalline by 21.5X.

[Test V] The same test as Test (2) was conducted by adjusting the feed material flow rate to each laminate to 400 m1/min, and the relevant parameters in steady operation were as follows.

1+=1.1 A: E l=12.7V;
D + = 10.5 umho; Cr = 600 u
mho; R+ = 68%1 m = 0.59A
; E213.9 V; Da = 0.3 umho
;Cr=1350gmho;Ra=78%D
2 exceeded the crystal quality of 35X.

[C series tests] Test conditions: Using a 225 μm ha mixture of sodium chloride and sodium bicarbonate at the same milligrams/liter as in the A series tests as feed: temperature 18°C; power supply 9 volts used in the A series tests. ,1
Amperage power.

[Test ■] Feed material flow rate to each lamination layer is 400 m1/m
The relevant parameters in steady-state operation were as follows.

■、Se0.81A; El=10. OV.

D+ = 6.56mho; C1 = 450μmh
o; R, = 68% 12 = 0.46 A: E2 = 11.4V:
Da=0.246mho; C,=1100u
mho; R2=77% Dl exceeded the quality of Dl by 27X.

[Test ■] The same test as Test ■ was conducted by adjusting the flow rate of the feed material to each laminate to 500 m1/min, and the relevant parameters in steady operation were as follows.

I = 0.91A; E, = 9.6V.

D+ = 9.0 gmho; Cr = 485 um
ho; R1=72% I2=0.50A; E2=11.3V
; Dl = 1.65 gmho ; Cx =
1001000u; Ra”78% Dl exceeded Dl crystallinity by 5.5x.

[Test ■] The same test as Test ■ was conducted by adjusting the flow rate of material supplied to each laminate to 300 m1/min, and the parameters related to steady operation were as follows.

1, = 0.70 A; El = 10.4V
:D, = 8.0 μmho; Cr = 500 g
mho; R, = 67% ra = 0.41 A; Ei = 11.6 v;
Da = 0.22 umho; Ct = 1
100 umho; R, = 77% D, exceeded the crystalline quality by only 36X.

[D Series Test] Test Conditions Two Same feed materials as C Series; power source changed to two similar variable feed power sources.

[Test ■] The feed flow rate to each laminate was adjusted to 400 m1/min, the applied cell-to-cell voltage was adjusted to 2 volts per each cell, and 3 volts was applied as the galvanic voltage. The relevant parameters in steady-state operation were as follows.

I, =0.64A; El =7. O.V.
.

D+ = 16.0 umho: Cr
= 440umho; R, = 65% Iz = 0.41 A: E* =
11.0 V; Da = 1.60 um
ho; C2=850unho; R1=7
4% D exceeded the crystallinity of Dl by IOX.

[Test

1, = 0.75 A; El = 9. O.V.
;D+ = 9.0umho: Cr = 500u
mh; R1=65%I t ” 0.52 A;
E2 = 15.0 V: Da = 0.70 um
ho; C, = 9806 mho; R, = 74% D, exceeded that of quartz by only 13X.

In all 10 comparative tests using various feed flow rates, different applied powers and feed material mixtures, the 13 inch long two pass laminate outperformed the 26 inch long single pass laminate. Ta. The performance of the two passes of the 13 inch length was better than a single 26 inch laminate. However, the water recovery rate in 9 out of 10 tests was high;
A concentrated stream of high conductivity was produced. High conductivity of the concentrate stream generally results in increased back-diffusion, but this was not reflected in these tests.

4. ti 8 Figure 1 is an exploded view of the electrodeionization device of the present invention, Figure 2 is a schematic diagram for explaining the operation of the device of the present invention, and Figure 3 is a schematic diagram for explaining the operation of the device of the present invention.
FIG. 4 is a perspective view of an electrode structure useful in the present invention; FIG. 4 is a perspective view of a spacer structure positioned adjacent the electrode of the present invention; FIG. 6 is a perspective view of the reduced compartment of the device of the invention; FIG. 7 is a detailed view of the liquid inlet of the structure of FIG. 6; and FIG. 8 is a perspective view of the structure of FIG. FIG. 9 is a schematic diagram of a second method described in Example I.

9.11: Electrode 10: Electrodeionization device 12: Stage 13: End plate 15: Bag member 16: Liquid inlet 17: End block 18: Electrode spacer 19 Screen 20: Ion permeable membrane 22; Spacer (optional) Flexible material) 26: Cation permeable membrane 28 Ni spacer (hard material) 30: Anion permeable membrane 32 Surroundings of the Ni spacer 38 Ni spacer (flexible material) 40: Ion exchange membrane 42: Electrode spacer 44: End block 50: End plate 52: Bag member 54: Conduit 56.58.60: Bolt Figure 2 Figure 4 Figure 5 Figure 6LI Figure 8 Figure 9 Procedural amendment (method) % formula % Incident display 1988 Patent Application No. 135750 Title of the invention Relationship with the electrodeionization method and device correction case Name of patent applicant Title
Miliboa Corporation

Claims (10)

[Claims] (1) at least one separation stage, the stage comprising: a cathode compartment located at a first end of the stage; and a cathode compartment located at an end opposite the first end of the stage; a plurality of alternating ion depletion compartments and ion concentration compartments disposed between the cathode compartment and the anode compartment, each of the ion depletion compartments having a spacer and a spacer; , a plurality of subcompartments formed by a plurality of ribs extending along the length of each of the ion depletion compartments, each subcompartment containing an ion exchange solid composition, each subcompartment comprising:
Approximately 0.3 inches to 4 inches (0.762 to 10
．． The width formed by the distance between the ribs is approximately 0.05 to 0.25 inches (0.127 to 0.16 cm).
635), wherein the thickness of the subcompartment is defined by an anion permeable membrane and a cation permeable membrane joined to each of the ribs along its length and to the spacer; Each of said enrichment compartments is free of ion exchange solid composition and further comprises means for passing the first liquid to be purified into at least two ion depletion compartments within said stage; means for passing a second liquid that receives ions from the first liquid into the enrichment compartment; means for applying a voltage between an anode in the anode compartment and a cathode in the compartment; and a means for applying a voltage between the anode in the anode compartment and the cathode in the compartment; and means for recovering purified liquid from the chamber. 2. The electrodeionization apparatus of claim 1, wherein the subcompartments have a width of about 0.5 to 1.5 inches (1.27 to 3.81 cm). (3) The thickness of the subdivision chamber is about 0.06 to 0.1.
The electrodeionization device of claim 1, wherein the electrodeionization device is 25 inches (0.152 to 0.318 cm). (4) An electrodeionization device according to claim 1, 2 or 3, further comprising means for creating turbulent flow of the second liquid within the concentration compartment. (5) the ion exchange composition comprises a mixture of anion exchange resin beads and cation exchange resin beads, wherein the volume ratio of anion exchange resin beads to cation exchange resin beads in the ion depletion compartment is about 2; Claims 1, 2 or 3 between .0 and 0.5.
Electrodeionization device as described in Section. (6) a plurality of separation stages, each stage comprising means for passing a second liquid through the enrichment compartment for receiving ions from a first liquid; an anode in the anode compartment; and an anode in the anode compartment; means for applying a voltage between the cathodes in the chamber;
and means for recovering purified liquid from said depletion compartment. 7. The electrodeionization apparatus of claim 6, wherein the subcompartments have a width of about 0.5 to 1.5 inches (1.27 to 3.81 cm). (8) The thickness of the subdivision chamber is about 0.06 to 0.1.
7. The electrodeionization device of claim 6, which is 25 inches (0.152 to 0.318 cm). (9) The electrodeionization device of claim 6, 7 or 8, further comprising means for creating turbulent flow of the second liquid within the concentration compartment. (10) The ion exchange composition includes a mixture of anion exchange resin beads and cation exchange resin beads, and the volume ratio of anion exchange resin beads to cation exchange resin beads in the reduction compartment is about 2.0 to 2.0. 0.5, the electrodeionization device according to claim 1.