CN215539863U - Multi-stage electrodialysis system for concentrating desulfurization wastewater - Google Patents
Multi-stage electrodialysis system for concentrating desulfurization wastewater Download PDFInfo
- Publication number
- CN215539863U CN215539863U CN202121930332.1U CN202121930332U CN215539863U CN 215539863 U CN215539863 U CN 215539863U CN 202121930332 U CN202121930332 U CN 202121930332U CN 215539863 U CN215539863 U CN 215539863U
- Authority
- CN
- China
- Prior art keywords
- electrodialysis
- water
- fresh water
- selective
- stage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
Abstract
The utility model relates to a multi-stage electrodialysis system for concentrating desulfurization wastewater, which consists of an N-stage electrodialysis system, a water inlet switching valve and a water outlet switching valve; each stage of electrodialysis system comprises: the device comprises a concentrated water tank, a fresh water tank, a selective electrodialysis membrane stack, a concentrated water circulating pump and a fresh water circulating pump, wherein the concentrated water tank is connected with a concentrated water outlet valve, the fresh water tank is connected with a fresh water inlet valve, a water outlet pipeline and a water inlet pipeline are arranged between the concentrated water tank and the selective electrodialysis membrane stack, and a water outlet pipeline and a water inlet pipeline are also arranged between the fresh water tank and the selective electrodialysis membrane stack. The utility model has the beneficial effects that: the selective electrodialysis membrane reactor is arranged, so that chloride ions and heavy metal ion pollutants can be enriched in concentrated water, recyclable sulfate ions are reserved in fresh water, and the concentration and decrement of high-salt desulfurization wastewater can be realized without additionally using a medicament. The multistage electrodialysis system is not only suitable for the concentration treatment of the desulfurization wastewater of the coal-fired power plant, but also can be used for the large-scale industrial wastewater treatment in other fields.
Description
Technical Field
The utility model belongs to the technical field of environment-friendly water treatment, and particularly relates to a multistage electrodialysis system for concentrating desulfurization wastewater.
Background
The desulfurization wastewater is discharged wastewater of a limestone-gypsum wet flue gas desulfurization system of a coal-fired power plant and contains extremely high-concentration Cl-、SO4 2-、Ca2+、Mg2+And various heavy metal ions, and has the characteristics of pollutant enrichment, large water quantity, large water quality fluctuation, difficult treatment and the like. With the proposal of 'deeply developing pollution control action and vigorously developing green economy', the traditional oxidation-neutralization-precipitation-flocculation-clarification treatment process cannot meet the current desulfurization wastewater treatment requirement, and zero emission of the desulfurization wastewater of a coal-fired power plant is imperative. In the process of continuously exploring the desulfurization wastewater zero-discharge process, researchers form various different treatment ideas taking pretreatment, concentration and decrement and evaporation and solidification as a common basic route. The concentration and decrement treatment of the desulfurization wastewater can effectively reduce the water amount of the tail end evaporation and solidification treatment, reduce the comprehensive treatment cost, realize the gradient utilization of water resources, and have important significance.
Selective electrodialysis is a new electrodialysis technique developed in recent years. The ion exchange membrane with the monovalent selective separation function is introduced into the electrodialysis membrane stack, and the monovalent ion and the multivalent ion can be selectively separated without adding a medicament. The existing selective electrodialysis systems for treating desulfurization wastewater are single-stage electrodialysis systems, salt concentration difference between a fresh water side and a concentrated water side in the later stage of concentration treatment causes increase of the migration rate of homonymous ions, the concentration effect of the desulfurization wastewater is seriously influenced, and the selective electrodialysis systems are not suitable for large-scale industrial wastewater treatment. To alleviate this negative effect caused by excessive solution concentration, increasing the number of electrodialysis stages to increase the effect of transferring counter ions and reducing the size of the stack in a single-stage electrodialysis reactor are often used in industry. The existing multistage electrodialysis systems are various in forms and are most common in multistage series reverse flow electrodialysis. The electrodialysis system is generally provided with fixed-stage electrodialysis reactors according to the quality of treatment liquid and treatment requirements, the electrodialysis stages cannot be adjusted according to field water quality fluctuation, and the electrodialysis system is directly used for concentration treatment of desulfurization wastewater of a coal-fired power plant and has the defects of electric energy waste, low current efficiency, poor concentration effect and the like. Therefore, there is a need to develop a new electrodialysis system.
SUMMERY OF THE UTILITY MODEL
The utility model aims to overcome the defects in the prior art and provide a multi-stage electrodialysis system for concentrating desulfurization wastewater.
The multi-stage electrodialysis system for concentrating the desulfurization wastewater consists of an N-stage electrodialysis system, a water inlet switching valve and a water outlet switching valve, wherein N is a natural number; each stage of electrodialysis system comprises: the device comprises a concentrated water tank, a fresh water tank, a selective electrodialysis membrane stack, a concentrated water circulating pump and a fresh water circulating pump, wherein the concentrated water tank is connected with a concentrated water outlet valve, the fresh water tank is connected with a fresh water inlet valve, a water outlet pipeline and a water inlet pipeline are arranged between the concentrated water tank and the selective electrodialysis membrane stack, and a water outlet pipeline and a water inlet pipeline are also arranged between the fresh water tank and the selective electrodialysis membrane stack; the concentrated water tanks of the electrodialysis systems are communicated through concentrated water interstage communication valves, and the fresh water tanks of the electrodialysis systems are communicated through fresh water interstage communication valves; the number of stages N of the electrodialysis system is determined by different incoming water quality and treatment requirements.
Preferably, the selective electrodialysis membrane stack consists of anion selective exchange membranes and common cation selective exchange membranes which are alternately arranged; the selective electrodialysis membrane stack is divided into a concentrated water channel and a fresh water channel which are equal in quantity, an anion selective exchange membrane or a cation selective exchange membrane is arranged between the adjacent concentrated water channel and the fresh water channel, and the anion selective exchange membrane and the cation selective exchange membrane in the selective electrodialysis membrane stack are alternately arranged; two polar water channels are arranged on two sides of the membrane stack, and the polar water channels, the polar water tank and the polar water pump jointly form polar water circulation which is a necessary part for conventional electrodialysis and mainly plays roles in preventing the scale formation of the polar plates and reducing the resistance; the water circulation of each stage of electrodialysis electrode is kept independent and is not overflowed or communicated.
Preferably, N is a natural number greater than 2.
Preferably, all electrodialysis systems in the N-stage electrodialysis system are connected in parallel and independently operated, or combined in a certain sequence and then operated in series; the electrodialysis systems of each stage may be of the same or different scale, for example A, B, C three electrodialysis systems, which may be operated individually or in different combinations in series.
Preferably, the water inlet switching valve, the water outlet switching valve, the concentrated water outlet valve, the concentrated water interstage communication valve, the fresh water inlet valve and the fresh water interstage communication valve are all electrically operated valves and can be opened or closed at the far end.
The utility model has the beneficial effects that:
the utility model discloses multistage electrodialysis system is multistage electrodialysis system of progression adjustable, reduces the salt concentration difference of operation in-process membrane stack dense water side and fresh water side, reduces the dotted ion migration rate of reactor, under the prerequisite of guaranteeing desulfurization waste water treatment effect, reduces the system energy consumption and improves single-stage electrodialysis efficiency, promotes desulfurization waste water treatment efficiency.
The selective electrodialysis membrane reactor is arranged, so that chloride ions and heavy metal ion pollutants can be enriched in concentrated water, recyclable sulfate ions are reserved in fresh water, and the concentration and decrement of high-salt desulfurization wastewater can be realized without additionally using a medicament. The multistage electrodialysis system is not only suitable for concentration treatment of desulfurization wastewater of a coal-fired power plant, but also can be used for large-scale industrial wastewater treatment in other fields, and has universality and universality.
Drawings
Fig. 1 is a schematic diagram of a multistage electrodialysis system for concentrating desulfurization waste water.
Description of reference numerals: the device comprises a concentrated water tank 1, a fresh water tank 2, a concentrated water outlet valve 3, a concentrated water interstage communication valve 4, a fresh water inlet valve 5, a fresh water interstage communication valve 6 and a selective electrodialysis membrane stack 7.
Detailed Description
The present invention will be further described with reference to the following examples. The following examples are set forth merely to aid in the understanding of the utility model. It should be noted that, for a person skilled in the art, several modifications can be made to the utility model without departing from the principle of the utility model, and these modifications and modifications also fall within the protection scope of the claims of the present invention.
The utility model provides a multi-stage electrodialysis system for treating desulfurization wastewater of a coal-fired power plant and concentrating the desulfurization wastewater, aiming at the problem of low efficiency in the prior selective electrodialysis for concentrating the desulfurization wastewater. The multistage electrodialysis system increases the number of electrodialysis stages on the basis of the conventional selective electrodialysis system, and is provided with a water inlet and outlet switching valve, so that the treatment flow direction of concentrated water and fresh water is changed. The water flow direction of the conventional series electrodialysis reactor is as follows: the first-level concentrated water-the second-level concentrated water … … N-level concentrated water, and the first-level fresh water-the second-level fresh water … … N-level fresh water. The water flow direction of the countercurrent multistage electrodialysis reactor is as follows: n-level fresh water, N-1 level fresh water … … level fresh water, and the flow direction of the fresh water is opposite to that of the concentrated water; the rated treatment water amount (namely, the rated output of the membrane stack) of each electrodialysis system stage can be the same or different.
Example one
The embodiment one of the application provides a multi-stage electrodialysis system for concentrating desulfurization wastewater as shown in figure 1:
the device consists of an N-stage electrodialysis system, a water inlet switching valve and a water outlet switching valve, wherein N is a natural number; each stage of electrodialysis system comprises: the device comprises a concentrated water tank 1, a fresh water tank 2, a selective electrodialysis membrane stack 7, a concentrated water circulating pump and a fresh water circulating pump, wherein the concentrated water tank 1 is connected with a concentrated water outlet valve 3, the fresh water tank 2 is connected with a fresh water inlet valve 5, a water outlet pipeline and a water inlet pipeline are arranged between the concentrated water tank 1 and the selective electrodialysis membrane stack 7, and a water outlet pipeline and a water inlet pipeline are also arranged between the fresh water tank 2 and the selective electrodialysis membrane stack 7; the concentrated water tanks 1 of the electrodialysis systems are communicated through concentrated water interstage communication valves 4, and the fresh water tanks 2 of the electrodialysis systems are communicated through fresh water interstage communication valves 6; the number of stages N of the electrodialysis system is determined by different incoming water quality and treatment requirements.
Example two
On the basis of the first embodiment, the second embodiment of the present application provides a method for operating the multi-stage electrodialysis system for concentrating desulfurization wastewater in the first embodiment in a coal-fired power plant:
a certain coal-fired power plant adopts single-stage selective electrodialysis concentration to treat desulfurization wastewater. The system has the advantages that the treated water amount is 0.5t/h, the average concentration of chloride ions in the high-salinity concentrated water outlet is about 35000mg/L, the high-salinity concentrated water enters a terminal wastewater treatment system for deep treatment, and the zero discharge of the wastewater of the power plant is realized. The average concentration of chloride ions in the low-salt fresh water effluent is about 3000mg/L, and the low-salt fresh water effluent is returned to the original desulfurization system for recycling. The average power of the membrane stack of the original system is 1.50kW, and the average current efficiency is 0.73. The quality of the outlet water of the system is unstable under the influence of the fluctuation of the quality of the inlet water.
In order to concentrate and treat the desulfurization wastewater (about 6t/h) of the whole coal-fired power plant, a new selective electrodialysis treatment system needs to be built. Is limited by the scale of an electrodialysis membrane stack, and can not produce single-stage super-large-scale electrodialysis. And then, a set of 4-stage countercurrent series connection selective electrodialysis system is designed and built by combining the selective electrodialysis technology and the multistage countercurrent electrodialysis technology, and the maximum output of each stage of system is the same. The system can independently operate all levels of selective electrodialysis, the flow direction of interstage concentrated water and the flow direction of interstage fresh water are reciprocal, and the level number of the electrodialysis in operation can be adjusted in time according to actual conditions. Since continuous operation, the system was operated in the 2-stage electrodialysis mode for 12% of the time, in the 3-stage electrodialysis mode for 66% of the time, and in the 4-stage electrodialysis mode for 22% of the time. The average power of the membrane stack of the system is 14.2kW, and the average current efficiency is 0.75. The average concentration of chloride ions in the high-salt concentrated water is about 44500mg/L, the average concentration of chloride ions in the low-salt fresh water is 1200mg/L, and the quality of the produced water is obviously improved.
The power plant multistage electrodialysis system is normally put into operation for more than 6 months, the concentration treatment effect of the desulfurization wastewater is stable, the quality of the fresh water produced water is obviously improved, and the expected treatment target is realized. The system is ingenious in design, convenient to operate, capable of operating in different levels according to requirements and low in operating cost. The results show that the multistage electrodialysis system and the treatment method for concentrating the desulfurization wastewater have good applicability.
The selective electrodialysis membrane stack of the present invention can migrate chloride ions and heavy metal ions on the fresh water side to the concentrated water side, but not much migration occurs when more than 99% of divalent anions (mainly sulfate radicals) stay on the fresh water side. On one hand, the method avoids scaling at the concentrated water side due to sulfate radical enrichment, and on the other hand, the fresh water outlet water can meet the recycling conditions (can be recycled to a desulfurization system).
The multistage electrodialysis system of the utility model: the concentrated water flows from the first-stage electrodialysis system to the final-stage electrodialysis system step by step, and the salt concentration is gradually increased; the fresh water flows from the final electrodialysis system to the first electrodialysis system step by step, and the salt concentration is gradually reduced. The strategy avoids the enhancement of the homonymous ion migration effect caused by the overlarge salt concentration difference of the concentrated water side and the fresh water side of the single-stage electrodialysis system, and improves the forward ion migration efficiency of the electrodialysis system to the maximum extent. The multistage electrodialysis system with adjustable stages is arranged, the number of the electrodialysis reactors can be adjusted in time according to the quality of the incoming water and the treatment requirement, and on the premise of ensuring the treatment effect of the desulfurization wastewater, the energy consumption of the system is reduced and the efficiency of the single-stage electrodialysis is improved.
The selective electrodialysis technology and the multistage countercurrent electrodialysis technology are combined, the electrodialysis stage number can be adjusted according to the fluctuation of the quality of the incoming water, different incoming water qualities and treatment requirements are met, and efficient and energy-saving treatment of the desulfurization wastewater is realized; the method avoids the enhancement of the homonymous ion migration effect caused by the overlarge salt concentration difference of the concentrated water side and the fresh water side of the single-stage electrodialysis, and improves the forward ion migration efficiency of the electrodialysis to the maximum extent; the multistage electrodialysis system is a multistage electrodialysis system with adjustable stages, salt concentration difference of a membrane stack concentrated water side and a fresh water side in the operation process is reduced, the homonymous ion migration rate of the reactors is reduced, the number of the electrodialysis reactors can be adjusted in time according to the quality of incoming water and treatment requirements, the energy consumption of the system is reduced, the single-stage electrodialysis efficiency is improved, and the desulfurization wastewater treatment efficiency is improved on the premise that the desulfurization wastewater treatment effect is ensured.
The selective electrodialysis membrane reactor is arranged, so that chloride ions and heavy metal ion pollutants can be enriched in concentrated water, recyclable sulfate ions are reserved in fresh water, and the concentration and decrement of high-salt desulfurization wastewater can be realized without additionally using a medicament. The multistage electrodialysis system is not only suitable for concentration treatment of desulfurization wastewater of a coal-fired power plant, but also can be used for large-scale industrial wastewater treatment in other fields, and has universality and universality.
Claims (5)
1. A multi-stage electrodialysis system for concentrating desulfurization wastewater is characterized by comprising an N-stage electrodialysis system, a water inlet switching valve and a water outlet switching valve, wherein N is a natural number; each stage of electrodialysis system comprises: the device comprises a concentrated water tank (1), a fresh water tank (2), a selective electrodialysis membrane stack (7), a concentrated water circulating pump and a fresh water circulating pump, wherein the concentrated water tank (1) is connected with a concentrated water outlet valve (3), the fresh water tank (2) is connected with a fresh water inlet valve (5), a water outlet pipeline and a water inlet pipeline are arranged between the concentrated water tank (1) and the selective electrodialysis membrane stack (7), and a water outlet pipeline and a water inlet pipeline are also arranged between the fresh water tank (2) and the selective electrodialysis membrane stack (7);
concentrated water tanks (1) of all stages of electrodialysis systems are communicated through concentrated water interstage communication valves (4), and fresh water tanks (2) of all stages of electrodialysis systems are communicated through fresh water interstage communication valves (6).
2. The multi-stage electrodialysis system for concentrating desulfurization waste water according to claim 1, wherein: the selective electrodialysis membrane stack (7) consists of anion selective exchange membranes and cation selective exchange membranes which are alternately arranged; the selective electrodialysis membrane stack (7) is divided into a concentrated water channel and a fresh water channel which are equal in quantity, an anion selective exchange membrane or a cation selective exchange membrane is arranged between the adjacent concentrated water channel and the adjacent fresh water channel, and the anion selective exchange membrane and the cation selective exchange membrane in the selective electrodialysis membrane stack (7) are alternately arranged; two sides of the membrane stack are provided with two polar water channels.
3. The multi-stage electrodialysis system for concentrating desulfurization waste water according to claim 1, wherein: n is a natural number greater than 2.
4. The multi-stage electrodialysis system for concentrating desulfurization waste water according to claim 1, wherein: all electrodialysis systems in the N-stage electrodialysis system are connected in parallel or combined in a certain sequence and then connected in series.
5. The multi-stage electrodialysis system for concentrating desulfurization waste water according to claim 1, wherein: the water inlet switching valve, the water outlet switching valve, the concentrated water outlet valve (3), the concentrated water interstage communication valve (4), the fresh water inlet valve (5) and the fresh water interstage communication valve (6) are all electrically operated valves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121930332.1U CN215539863U (en) | 2021-08-16 | 2021-08-16 | Multi-stage electrodialysis system for concentrating desulfurization wastewater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121930332.1U CN215539863U (en) | 2021-08-16 | 2021-08-16 | Multi-stage electrodialysis system for concentrating desulfurization wastewater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215539863U true CN215539863U (en) | 2022-01-18 |
Family
ID=79836499
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121930332.1U Active CN215539863U (en) | 2021-08-16 | 2021-08-16 | Multi-stage electrodialysis system for concentrating desulfurization wastewater |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215539863U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11502323B1 (en) | 2022-05-09 | 2022-11-15 | Rahul S Nana | Reverse electrodialysis cell and methods of use thereof |
| US11502322B1 (en) | 2022-05-09 | 2022-11-15 | Rahul S Nana | Reverse electrodialysis cell with heat pump |
| US11855324B1 (en) | 2022-11-15 | 2023-12-26 | Rahul S. Nana | Reverse electrodialysis or pressure-retarded osmosis cell with heat pump |
-
2021
- 2021-08-16 CN CN202121930332.1U patent/CN215539863U/en active Active
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11502323B1 (en) | 2022-05-09 | 2022-11-15 | Rahul S Nana | Reverse electrodialysis cell and methods of use thereof |
| US11502322B1 (en) | 2022-05-09 | 2022-11-15 | Rahul S Nana | Reverse electrodialysis cell with heat pump |
| US11563229B1 (en) | 2022-05-09 | 2023-01-24 | Rahul S Nana | Reverse electrodialysis cell with heat pump |
| US11611099B1 (en) | 2022-05-09 | 2023-03-21 | Rahul S Nana | Reverse electrodialysis cell and methods of use thereof |
| US11699803B1 (en) | 2022-05-09 | 2023-07-11 | Rahul S Nana | Reverse electrodialysis cell with heat pump |
| US11855324B1 (en) | 2022-11-15 | 2023-12-26 | Rahul S. Nana | Reverse electrodialysis or pressure-retarded osmosis cell with heat pump |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN215539863U (en) | Multi-stage electrodialysis system for concentrating desulfurization wastewater | |
| CN103723799B (en) | Electrodialyzer and near-zero-release industrial wastewater recycling technique | |
| CN108862548B (en) | Reactor device of microbial electrolysis desalting tank | |
| CN214400132U (en) | System of clean energy sea water desalination coupling salt difference energy power generation facility | |
| CN112723640A (en) | System and method for clean energy sea water desalination coupling salt difference energy power generation device | |
| CN109052745B (en) | Concentration and reduction method for easily-scaling wastewater | |
| CN211255496U (en) | High-standard advanced treatment system for refractory organic matters in comprehensive wastewater of industrial park | |
| CN113477089A (en) | Multi-stage electrodialysis system for concentrating desulfurization wastewater and treatment method | |
| CN212356664U (en) | Electrodialysis reactor for preventing cathode plate from scaling | |
| CN111439814A (en) | Desulfurization wastewater concentration and reduction treatment system and method based on non-softening and directional driving electrodialysis technology | |
| CN212269733U (en) | Electrodialysis device for preventing polar water system from scaling by adopting directional driving technology | |
| CN210145851U (en) | Efficient water-saving system for circulating water pollution discharge | |
| CN115093082A (en) | Waste water treatment process and device for landfill leachate and DTRO concentrated solution | |
| CN215208906U (en) | Electric deionization desalination device applied to high-voltage direct-current transmission valve cooling system | |
| CN212292942U (en) | Desulfurization wastewater concentration decrement processing system based on directional driving electrodialysis technology | |
| CN212269765U (en) | Concentrated decrement device of power plant's desulfurization waste water | |
| CN211946640U (en) | System for treating cadmium-containing wastewater generated in cadmium telluride thin film solar cell production | |
| CN211971850U (en) | Waterway system and water purifying equipment | |
| CN210065273U (en) | Multistage electrochemical water treatment system | |
| CN114212859A (en) | Two-stage electrochemical crosslinking electrodialysis desalination treatment system and application thereof | |
| CN219752007U (en) | Electrodialysis treatment system | |
| CN215463321U (en) | Reverse flow electrodialysis reactor | |
| CN203890183U (en) | Seawater desalting device adopting magnetizing centrifugation | |
| CN207659238U (en) | A kind of film electricity combination water treatment facilities | |
| CN206843153U (en) | Electrochemistry removes Determination of Total Nitrogen in Waste Water plug flow diaphragm electrolysis apparatus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |