Novel electrodialysis equipment

Abstract

The embodiment of the utility model discloses novel electrodialysis equipment which comprises a plurality of circulating tanks, circulating pumps and spiral-wound membranes, the circulating tanks and the circulating pumps are connected through pipelines, the number of the circulating tanks and the number of the circulating pumps are four, the number of inlets and the number of outlets of the spiral-wound membranes are both six, four inlets are connected with the circulating pumps through pipelines, and four outlets are connected with the circulating pumps through pipelines. The two inlets are respectively a positive electrode liquid inlet and a negative electrode liquid inlet, the two outlets are respectively a positive electrode liquid outlet and a negative electrode liquid outlet, and the positive electrode liquid inlet and the negative electrode liquid inlet are respectively connected with the electrode liquid box through pipelines; according to the utility model, the salt crystallization on the surface of the membrane is avoided, the membrane flux is greatly improved, and the occupied area is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of water treatment, in particular to a novel electrodialysis device. Background Art

[0002] Traditional electrodialysis (ED) is a membrane separation technology that uses potential difference as a driving force and the selective permeability of ion exchange membranes to remove or enrich electrolytes from solutions.

[0003] The selectivity of conventional electrodialysis depends on the ion exchange membrane used. The ion exchange membrane is based on a polymer with ionizable active groups attached.

[0004] Anion exchange membrane is referred to as anion membrane, and its active group is usually amino. Cation exchange membrane is referred to as cation membrane, and its active group is usually sulfonate. The selective permeability of ion exchange membrane means that the fixed ion groups on the membrane attract the oppositely charged ions in the solution outside the membrane, allowing it to pass through the membrane under the promotion of potential difference or concentration difference, while repelling ions of the same charge and preventing them from entering the membrane.

[0005] Therefore, cations can pass through the cationic membrane and anions can pass through the anionic membrane.

[0006] According to the uniformity of the distribution of active groups in the membrane, ion exchange membranes can be roughly divided into heterogeneous membranes, homogeneous membranes and semi-homogeneous membranes. Styrene grafted polymers of polyethylene, polypropylene, polyvinyl chloride, etc. are the most commonly used membrane materials for ion exchange membranes. The best performance is the ion exchange membrane prepared with perfluorosulfonic acid and perfluorocarboxylic acid membrane materials.

[0007] According to the uniformity of the distribution of active groups in the membrane, ion exchange membranes can be roughly divided into heterogeneous membranes, homogeneous membranes and semi-homogeneous membranes. Styrene grafted polymers of polyethylene, polypropylene, polyvinyl chloride, etc. are the most commonly used membrane materials for ion exchange membranes. The best performance is the ion exchange membrane prepared with perfluorosulfonic acid and perfluorocarboxylic acid membrane materials.

[0008] use:

[0009] 1). As a pre-desalting treatment for ion exchange process, it can greatly reduce the desalting load of ion exchange, expand the adaptability of ion exchange to raw water, and significantly reduce the discharge of waste acid, waste alkali or waste salt during ion exchange regeneration, generally by 90% or even more. In some cases, electrodialysis can completely replace ion exchange and directly produce primary pure water.

[0010] 2) Concentrate, recover and reuse the useful electrolytes in the wastewater, such as the recovery and reuse of nickel-containing electroplating wastewater.

[0011] 3). Reform the original process and adopt electrodialysis technology to achieve clean production. For example, electrodialysis can be used to produce primary pure water or softened water instead of ion exchange to eliminate the generation of regeneration waste liquid; resin electrodialysis can be used to produce high-purity water and chemical regeneration of resin can be eliminated; ion exchange membrane diffusion dialysis can be used to recover acid from steel cleaning waste liquid, etc.

[0012] Traditional electrodialysis (ED) equipment and process flow mainly face the following problems:

[0013] (1) Plate-type membranes use a large amount of membranes and are expensive. They occupy a large area and have certain requirements for the placement location, which requires a flat ground, less dust, less vibration, avoid direct sunlight, have smooth ventilation, suitable temperature, and are not prone to condensation.

[0014] (2) The product concentration is low and the market value is not high

[0015] (3) Low membrane flux, short life, and low water recovery rate. Utility Model Content

[0016] The utility model provides a novel electrodialysis device, which avoids salt crystallization on the membrane surface, greatly improves the membrane flux and reduces the occupied area.

[0017] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0018] The utility model discloses a novel electrodialysis device, comprising a plurality of circulation tanks, circulation pumps and roll-type membranes, wherein the circulation tanks and the circulation pumps are connected through pipelines, the number of the circulation tanks and the circulation pumps is 4, the roll-type membrane is provided with 6 inlets and outlets, wherein 4 inlets are connected with the circulation pump through pipelines, 2 inlets are respectively a positive electrode anode liquid inlet and a negative electrode liquid inlet, wherein 2 outlets are a positive electrode liquid outlet and a negative electrode liquid outlet, the positive electrode liquid inlet and the negative electrode liquid inlet are respectively connected with a cathode liquid box through pipelines, and the circulation pump, a safety filter and a heat exchanger are provided on the connecting pipelines between the cathode liquid box and the positive electrode liquid outlet and the negative electrode liquid outlet.

[0019] Preferably, the circulation pump connected to the circulation tank is also connected to a safety filter, wherein two safety filters are also respectively connected to a heat exchanger.

[0020] Preferably, the rolled membrane includes a distribution plate, a guide disk, an outer tube and a central pull rod, both ends of the outer tube are installed on the guide disk, the distribution plates are installed at the ends of the two guide disks, the intermediate positive electrode rod end plate is installed in the middle of the front end of the two guide disks, the central pull rod passes through the two distribution plates and the two intermediate positive electrode rod end plates, the inner anode titanium tube is installed between the two intermediate positive electrode rod end plates, the outer cathode tube is installed on the inner wall of the outer tube, a partition is arranged between the inner anode titanium tube and the outer cathode tube, and the cathode membrane and the cathode membrane are arranged on the partition.

[0021] Preferably, the material of the outer tube is nylon.

[0022] Preferably, both ends of the central tie rod are provided with external threads, and the outer sides of the central tie rod connected with the distribution plate and the guide plate are provided with hexagonal nuts.

[0023] Preferably, the partition is provided with 4 groups of spiral grooves, and 2 negative membranes and 2 positive membranes are arranged at intervals at the spiral grooves.

[0024] Compared with the prior art, the beneficial effects of the utility model are:

[0025] The utility model redesigns the membrane structure, replaces the traditional plate membrane, avoids salt crystallization on the membrane surface, and periodically cycles the solution concentration to break the concentration polarization. The roll structure improves the membrane flux, which is 3-5 times that of the traditional flat plate structure. The roll membrane greatly reduces the floor space, reducing the floor space by 70%, and reducing energy consumption and operating costs by 2 / 3. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a working schematic diagram of an embodiment of the utility model.

[0027] Figure 2 It is a schematic diagram of the prior art.

[0028] Figure 3 It is a schematic diagram of the plate mold of the prior art.

[0029] Figure 4 It is a top view of the roll-up film according to an embodiment of the utility model.

[0030] Figure 5 yes Figure 4 Middle AA section view.

[0031] Figure 6 It is a partial cross-sectional view of the roll film of the embodiment of the utility model. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0033] As shown in the figure, the utility model discloses a novel electrodialysis equipment, including a plurality of circulation tanks 1, circulation pumps 2 and roll membranes 3, the circulation tanks 1 and the circulation pumps 2 are connected by pipelines, the number of the circulation tanks 1 and the circulation pumps 2 is 4, the roll membrane 3 is provided with 6 inlets and outlets, of which 4 inlets B are connected to the circulation pump 2 through pipelines, 2 inlets are respectively the positive electrode cathode liquid inlet 5 and the negative electrode cathode liquid inlet 6, 2 outlets are the positive electrode cathode liquid outlet and the negative electrode cathode liquid outlet, the positive electrode cathode liquid inlet 5 and the negative electrode cathode liquid inlet 6 are respectively connected to the cathode liquid box 7 through pipelines, and the circulation pump 2, the safety filter 8 and the heat exchanger 9 are provided on the connecting pipelines between the cathode liquid box 7 and the positive electrode cathode liquid outlet and the negative electrode cathode liquid outlet.

[0034] The utility model designs a roll-type film 3 to replace the plate-type film 4 in the prior art. The volume of the roll-type film 3 is compared with the plate-type film 4, and the occupied area is greatly reduced.

[0035] In one embodiment of the utility model, the circulation pump connected to the circulation tank is also connected to the security filter 8, wherein two security filters 8 are also respectively connected to the heat exchanger 9. Pure water is placed in the two circulation tanks here, and the reactants, i.e., high-concentration raw material liquid, such as sodium chloride or ammonium bicarbonate, are placed in the other two circulation tanks, and high-concentration product liquid is generated through the reaction of the spiral membrane 3. Of course, since the generation takes time, low-concentration raw material liquid may be generated at the beginning of production, and low-concentration product liquid will also be generated. The low-concentration raw material liquid and low-concentration product liquid are then placed in the circulation tank previously filled with pure water for circulation.

[0036] In one embodiment of the utility model, the roll membrane 3 includes a distribution plate 10, a guide plate 11, an outer tube 12 and a central tie rod 13. Both ends of the outer tube 12 are mounted on the guide plate 11. The distribution plate 10 is mounted at the ends of the two guide plates 11. The inlet and outlet of the roll membrane 3 are both arranged on the distribution plate 10. The middle of the front end of the two guide plates 11 is installed with an intermediate positive electrode rod end plate 14. The central tie rod 13 passes through the two distribution plates 10 and the two intermediate positive electrode rod end plates 14. The inner anode titanium tube 15 is installed between the two intermediate positive electrode rod end plates 14. The inner wall of the outer tube 12 is installed with an outer cathode tube 16. A partition 17 is arranged between the inner anode titanium tube 15 and the outer cathode tube 16. The cathode membrane C and the cathode membrane D are arranged on the partition 17. The cathode liquid is located in the gap between the inner anode titanium tube 15 and the partition 17, and the cathode liquid is located in the gap between the outer cathode tube 16 and the partition 17. The utility model changes the plate-type membrane into a roll-type membrane, and the membrane changes from a stacked state to a roll-type state, thereby reducing the occupied area and improving the efficiency during the reaction.

[0037] In one embodiment of the present invention, the material of the outer tube 12 is nylon.

[0038] In an embodiment of the present invention, both ends of the central tie rod 13 are provided with external threads, and the outer side where the central tie rod is connected with the distribution plate and the guide plate is provided with a hexagonal nut 18.

[0039] In one embodiment of the utility model, the partition plate 17 is provided with 4 groups of spiral grooves, and 2 female membranes and 2 male membranes are arranged at intervals at the spiral grooves. The design of the spiral grooves makes the female membranes and the male membranes spaced apart and increases the contact area.

[0040] The above contents are merely examples and explanations of the structure of the present utility model. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the present utility model or exceed the scope defined in the claims, they should all fall within the protection scope of the present utility model.

Claims

1. A novel electrodialysis device, characterized in that: It includes several circulation tanks, circulation pumps and roll membranes. The circulation tanks and circulation pumps are connected by pipelines. There are 4 circulation tanks and circulation pumps. The roll membrane has 6 inlets and outlets, of which 4 inlets are connected to the circulation pumps through pipelines, 2 inlets are the positive electrode liquid inlet and the negative electrode liquid inlet respectively, and 2 outlets are the positive electrode liquid outlet and the negative electrode liquid outlet. The positive electrode liquid inlet and the negative electrode liquid inlet are connected to the liquid tank through pipelines respectively. The circulation pump, safety filter and heat exchanger are arranged on the connecting pipelines between the liquid tank and the positive electrode liquid outlet and the negative electrode liquid outlet.

2. A novel electrodialysis device according to claim 1, characterized in that: The circulation pump connected to the circulation tank is also connected to the safety filter, and two safety filters are also respectively connected to the heat exchanger.

3. A novel electrodialysis device according to claim 1, characterized in that: The rolled membrane includes a distribution plate, a guide plate, an outer tube and a central pull rod. Both ends of the outer tube are installed on the guide plate, the distribution plates are installed at the ends of the two guide plates, the intermediate positive electrode rod end plate is installed in the middle of the front end of the two guide plates, the central pull rod passes through the two distribution plates and the two intermediate positive electrode rod end plates, the inner anode titanium tube is installed between the two intermediate positive electrode rod end plates, the outer cathode tube is installed on the inner wall of the outer tube, a partition is arranged between the inner anode titanium tube and the outer cathode tube, and the cathode membrane and the cathode membrane are arranged on the partition.

4. A novel electrodialysis device according to claim 3, characterized in that: The material of the outer tube is nylon.

5. A novel electrodialysis device according to claim 3, characterized in that: External threads are arranged at both ends of the central tie rod, and hexagonal nuts are arranged on the outer sides where the central tie rod is connected with the distribution plate and the guide plate.

6. A novel electrodialysis device according to claim 3, characterized in that: The partition is provided with 4 groups of spiral grooves, and 2 negative membranes and 2 positive membranes are arranged at intervals at the spiral grooves.

Images