Anti-blocking electrodialysis wastewater treatment system and method for resource utilization of carbon dioxide

Abstract

The invention belongs to the field of high-salt industrial wastewater treatment, and discloses an anti-blocking electrodialysis wastewater treatment system and method for resource utilization of carbon dioxide. The system comprises a water inlet subsystem, a security subsystem and an electrodialysis subsystem. The problems that suspended impurities in the high-salt industrial wastewater block a membrane stack and concentrated salt scale blocks the membrane stack are solved, CO2 in the chemical technological process is utilized, CO2 resource utilization is achieved, and the efficient and stable operation time of electrodialysis is prolonged.

Description

Technical Field

[0001] The present invention belongs to the field of high-salt industrial wastewater treatment, and more specifically, relates to an anti-clogging electrodialysis wastewater treatment system and method for resource utilization of carbon dioxide. Background Art

[0002] At present, the reuse rate of industrial water above a certain scale has reached more than 91%. In order to improve the reuse rate of industrial wastewater, the demand for resource treatment of high-salt industrial wastewater has gradually increased. Electrodialysis technology has the advantages of simple operation, wide treatment range and no pollution to the environment. It has important applications in the process of realizing wastewater resource utilization and recycling of high-salt industrial wastewater. Electrodialysis technology uses its unique separation mechanism, the selective permeability of anion permeable membranes and cation permeable membranes to anions and cations, and relies on the action of direct current electric fields to cause directional migration of anions and cations. It can effectively realize the desalination of industrial wastewater, obtain fresh water for reuse, and concentrate salt to further recycle salt resources, thus realizing wastewater resource utilization.

[0003] However, during the operation of the electrodialysis device, the membrane stack often becomes clogged, which makes it difficult for the electrodialysis device to operate continuously and reduces the processing capacity of the electrodialysis technology. The blockage of the membrane stack is mainly caused by two reasons: the blockage of impurities in the industrial wastewater and the blockage caused by scaling after the salt concentration in the cathode chamber. For the blockage of the membrane stack by impurities in industrial wastewater, the current main method is to increase the front-end pretreatment process or add a security filter to remove the suspended impurities in the wastewater. However, adding a pretreatment process will increase the process floor space and the cost of wastewater treatment needs to be further reduced. If only a security filter is added, due to the large number of suspended impurities in the wastewater, the security filter needs to be replaced frequently, the cost is high and it still affects the continuous operation of the electrodialysis device. For the scaling of the membrane stack, salt concentration mainly occurs in alkaline industrial wastewater. After concentration by the anion exchange membrane, the cathode chamber Ca 2+ ,Mg 2+ , CO 3 2- Ions are concentrated or polarized to produce OH - The precipitation of Ca salt and Mg salt causes membrane stack scaling. Currently, frequent polarity reversal and addition of acid solution are mainly used to inhibit membrane stack scaling, but frequent polarity reversal affects the continuous operation of the electrodialysis device, and the addition of acid solution increases the process operation cost. A better solution is needed for the blockage problem of membrane stack in electrodialysis device to ensure the long-term stable operation of the electrodialysis device.

[0004] Chinese Patent Publication No. CN109250846A discloses a salt-containing wastewater treatment system for inhibiting scale formation. The wastewater reduction unit, which consists of a homogenization water tank, a coagulation tank, a flocculation tank, a sedimentation tank, a first filter, and a dosing unit, pre-treats the wastewater, and the electrodialysis unit, which consists of the first, second, third, and fourth intermediate water tanks, the first and second reverse osmosis devices, a microfiltration unit, and an electrodialysis device. This process has a complex composition, requires multiple lift pumps to provide transfer driving force, has a high floor area and energy consumption, and a high construction cost.

[0005] Chinese Patent Publication No. CN112408558A discloses an anti-scaling electrodialysis system and treatment process based on pH control. It includes an electrodialysis reactor, a fresh water tank, a concentrated water tank, a pH control system, and an acid absorption system. The pH control system, which consists of an acid storage tank, an acid addition pump, a pipeline mixer, and an on-line pH meter, adds strong acid to the wastewater to regulate the pH to avoid membrane stack scaling. However, this method requires the installation of a pH control system, which has potential safety hazards and causes a significant increase in costs. Summary of the Invention

[0006] Electrodialysis is an important means for desalinating high-salt industrial wastewater and realizing wastewater recycling, with the advantages of simple operation, wide treatment range, and no environmental pollution. The object of the present invention is to address the problems that the membrane stack blockage of the electrodialysis device restricts the efficient and stable operation of the electrodialysis device, reduces the electrodialysis treatment capacity, and causes a decrease in the current efficiency of the electrodialysis device. The present invention proposes an anti-blocking electrodialysis wastewater treatment system and method for the resource utilization of carbon dioxide. The present invention solves the problems of blockage of the membrane stack by suspended impurities and scaling blockage of the concentrated salt in high-salt industrial wastewater in an integrated manner, and utilizes CO 2 in the chemical process, realizing the resource utilization of CO 2 and extending the efficient and stable operation time of electrodialysis.

[0007] To achieve the above object, in the first aspect of the present invention, an anti-blocking electrodialysis wastewater treatment system for the resource utilization of carbon dioxide is provided. The system includes an inlet water subsystem, a security subsystem, and an electrodialysis subsystem;

[0008] The inlet water subsystem includes a first water tank, a second water tank, a micro-nano bubble generator, and a slag scraping device; the first water tank and the second water tank are connected in the upper part; the micro-nano bubble generator is arranged at the bottom of the first water tank and the second water tank for generating CO 2The bubbles are introduced into the first water tank and the second water tank; the slag scraping device is arranged above the first water tank for scraping suspended impurities in the water; a slag discharge port is arranged at the upper part of the first water tank, and a water inlet pipe is connected to the lower part of the first water tank, and a chemical dosing port is arranged on the water inlet pipe; a fresh water overflow port is arranged at the upper part of one side wall of the second water tank relative to the first water tank; a water outlet pipe is connected to the bottom of the second water tank;

[0009] The security subsystem includes a security filter and an electrode water tank; the water outlet pipe is connected to the water inlet end of the security filter, and the water outlet end of the security filter is connected with a concentrated water inlet pipe and a fresh water inlet pipe; the electrode water tank is provided with an electrode water outlet pipe and an electrode water inlet pipe;

[0010] The electrodialysis subsystem includes a membrane stack assembly and an electrode device; a plurality of cation exchange membranes and anion exchange membranes are alternately arranged in the membrane stack assembly, and adjacent anion exchange membranes and cation exchange membranes form adjacent fresh water chambers and concentrated water chambers; the concentrated water inlet pipe is connected to the concentrated water chamber, and the concentrated water chamber is connected to a concentrated water tank with a concentrated water overflow port at the upper part through a concentrated water production pipe; the fresh water inlet pipe is connected to the fresh water chamber, and the fresh water chamber is connected to the second water tank through a fresh water production pipe; the electrode device includes a transformable cathode and anode, the cathode and anode are arranged on both sides of the membrane stack assembly, and one side of the cathode and anode adjacent to the membrane stack assembly respectively forms an electrode chamber with the membrane stack assembly; the electrode water outlet pipe and the electrode water inlet pipe are used to realize the circulating flow of the electrode water in the electrode water tank between the electrode chamber and the electrode water tank.

[0011] In the present invention, the concentrated water inlet pipe is used to send the concentrated water inlet of the security filter into the concentrated water chamber, and the concentrated water chamber is connected to a concentrated water tank with a concentrated water overflow port at the upper part through a concentrated water production pipe; the fresh water inlet pipe is used to send the fresh water inlet of the security filter into the fresh water chamber, and the fresh water chamber is connected to the second water tank through a fresh water production pipe.

[0012] According to the present invention, preferably, the first water tank is provided with a first side wall and a second side wall, a slag discharge overflow weir and a water outlet overflow weir are respectively arranged at the upper parts of the first side wall and the second side wall, the first water tank is communicated with the second water tank through the water outlet overflow weir, the slag discharge overflow weir is arranged close to the slag discharge port, and a water inlet is arranged at the lower part of the first side wall and is connected to the water inlet pipe.

[0013] According to the present invention, preferably, the water inlet subsystem further includes an air inlet, and the air inlet is communicated with the micro-nano bubble generator. In the present invention, the micro-nano bubble generator penetrates through the bottom of the second side wall of the first water tank, so that the micro-nano bubble generator is arranged at the bottoms of the first water tank and the second water tank.

[0014] According to the present invention, preferably, a turbidity on-line detector is arranged at the water outlet overflow weir.

[0015] According to the present invention, preferably, the micro-nano bubble generator is equipped with a pressure regulator.

[0016] According to the present invention, preferably, a slag discharge overflow weir is provided at the slag discharge port.

[0017] According to the present invention, preferably, a pH on-line detector and a first conductivity on-line monitor are provided at the fresh water overflow port.

[0018] According to the present invention, preferably, a baffle is provided inside the second water tank for separating the drainage from the first water tank and the drainage from the fresh water production pipe. Specifically, in the present invention: the second water tank is divided into left and right two regions by the baffle provided in the middle. The region close to the first water tank (left region) is mainly the drainage from the first water tank, which is subjected to the pH adjustment effect of the CO 2 supplemented by the micro-nano bubble generator at the lower part, and then enters the security filter from the bottom of the left region of the second water tank; the drainage from the fresh water production pipe enters the right region of the second water tank from the upper part of the right region, and is subjected to multiple electrodialysis cycle treatments together with the water to be entered into the electrodialysis subsystem at the bottom of the second water tank. The fresh water overflow port is also at the upper part of the right region, and the treated drainage from the fresh water production pipe is recovered by overflow through the fresh water overflow port. Moreover, the flow rate of the water outlet pipe at the bottom of the second water tank is greater than the overflow flow rate of the first water tank to the second water tank, realizing multiple cycle treatments of the wastewater and improving the treatment effect. At the same time, the fresh water production pipe enters the second water tank at the upper right part of the second water tank, avoiding mixing with the wastewater that has not been treated by the second water tank and overflowed from the first water tank to the second water tank. The drainage from the fresh water production pipe only mixes with the treated wastewater in the second water tank, ensuring the treatment effect of the fresh water recovered by overflow at the upper right fresh water overflow port.

[0019] According to the present invention, preferably, a water outlet flow regulating device is provided on the water outlet pipe.

[0020] In the present invention, a first conductivity on-line monitor is provided at the fresh water overflow port of the second water tank, and a water outlet flow regulating device is provided at the water outlet pipe. By monitoring the conductivity of the drainage at the fresh water overflow port and adjusting the water outlet flow rate, multiple purifications can be achieved for the fresh water circulation treatment, and the conductivity of the produced fresh water can be reduced. Preferably, by using the water outlet flow regulating device, the flow rate of the water outlet pipe at the bottom of the second water tank is regulated to be 1-5 times the overflow flow rate of the first water tank to the second water tank; the flow rate of the fresh water overflow port of the second water tank is 0.5-0.9 times the overflow flow rate of the first water tank to the second water tank.

[0021] According to the present invention, preferably, a detachable filter bag and a differential pressure gauge are provided inside the security filter. The aperture of the filter holes of the detachable filter bag is 1-500 μm. In the present invention, the size of the filter bag is selected according to the turbidity of the deslagged wastewater. Preferably, the sizes of the detachable filter bags are 5 μm and 12 μm; a concentrated and fresh water flow distribution device is provided between the detachable filter bag and the water outlet end of the security filter.

[0022] In the present invention, the detachable filter bag can further protect the electrodialysis membrane stack from being blocked by suspended impurities in the wastewater.

[0023] According to the present invention, preferably, the electrode device includes 3-15 pairs of cathode and anode electrode pairs; the membrane stack components are provided between the cathode and anode of each pair of electrode pairs and between adjacent electrode pairs;

[0024] Each membrane stack component is provided with 3-20 cation exchange membranes, and the number of anion exchange membranes in each membrane stack component is one less than the number of cation exchange membranes in the same membrane stack component.

[0025] According to the present invention, preferably, the side of the cathode adjacent to the membrane stack component forms a cathode chamber with the membrane stack component; the side of the anode adjacent to the membrane stack component forms an anode chamber with the membrane stack component.

[0026] According to the present invention, preferably, the electrode device further includes a DC power supply with adjustable voltage, including reverse power supply connection, and preferably the voltage is 90-120V.

[0027] According to the present invention, preferably, a second on-line conductivity monitor is provided in the cathode chamber.

[0028] According to the present invention, preferably, a concentrated water return pipe is connected to the bottom of one side side wall of the concentrated water tank. The concentrated water return pipe is used to send the concentrated water production of the concentrated water tank and the concentrated water inlet of the security filter into the concentrated water chamber together with the concentrated water inlet pipe.

[0029] According to the present invention, preferably, a regulating valve is provided on the concentrated water return pipe.

[0030] According to the present invention, preferably, a third on-line conductivity monitor is provided at the concentrated water overflow port.

[0031] The second aspect of the present invention provides a method for treating anti-clogging electrodialysis wastewater for resource utilization of carbon dioxide. The method uses the above system and includes the following steps:

[0032] S1: Feed the high-salt industrial wastewater and the medicament into the first water tank through the water inlet pipe and the medicine adding port respectively; feed the CO 2The mixed gas is formed into bubbles by the micro-nano bubble generator and sent into the first water tank and the second water tank; above the first water tank, the scum, suspended impurities and foam in the first water tank are discharged from the system through the slag discharge port by the slag scraping device, and the waste water after slag removal enters the second water tank;

[0033] S2: The waste water after slag removal in the second water tank is sent into the security filter through the water outlet pipe for filtration; concentrated water inlet and fresh water inlet are obtained at the water outlet end of the security filter; the concentrated water inlet and the fresh water inlet are respectively sent into the concentrated water chamber and the fresh water chamber for electrodialysis treatment; meanwhile, the electrode water in the electrode water tank circulates between the electrode chamber and the electrode water tank by using the electrode water outlet pipe and the electrode water inlet pipe;

[0034] S3: Concentrated water production water is obtained in the concentrated water chamber and sent into the concentrated water tank through the concentrated water production water pipe, and high-salt waste water is recovered through the concentrated water overflow port and further separated to recover salt resources; fresh water production water is obtained in the fresh water chamber and sent into the second water tank through the fresh water production water pipe, and fresh water resources are recovered through the fresh water overflow port.

[0035] According to the present invention, preferably, in step S1: the water quality conditions of the high-salt industrial waste water include: pH is 7 - 8.5, conductivity is 800 - 5000 μs / cm, total hardness is 50 - 400 mg / L, total alkalinity is 50 - 800 mg / L, TDS is 300 - 2500 mg / L, COD is 30 - 100 mg / L, TOC is 6 - 25 mg / L, and turbidity is 1.0 - 3.5 NTU. According to the present invention, preferably, in step S1: the medicament is at least one of a coagulant, a flocculant and a scale inhibitor, and preferably, the dosage ratio of the coagulant, the flocculant and the scale inhibitor is (1 - 10):(150 - 300):(0.1 - 1.5).

[0036] In the present invention, in the first water tank, the bubbles generated by the micro-nano bubble generator carry the medicament and move from bottom to top. While the bubbles play a role in dispersing the medicine, they also capture the suspended solids in the waste water to the upper part of the first water tank. The upper part of the first water tank discharges the scum, suspended impurities and foam from the system through the slag scraping device, obtains the waste water after slag removal and enters the second water tank through the water outlet overflow weir. In the second water tank, a mixed gas containing CO 2 is introduced through the micro-nano bubble generator, which reduces the pH of the waste water and increases the HCO 3 - and H 2 CO 3 concentrations in the waste water, improves the pH stability of the waste water, and resists the OH - generated by the concentration difference polarization of the membrane stack during the electrodialysis operation with impact.

[0037] According to the present invention, preferably, in step S1: the size of the bubbles is adjusted by the pressure regulator, and the diameter of the bubbles is 1 μm to 80 μm, preferably 20 to 40 μm.

[0038] According to the present invention, preferably, in step S1: the CO 2 -containing mixed gas is the gas obtained by the flue gas capture and separation process and / or the gas obtained after the flue gas is purified by dust removal, desulfurization and denitrification. The temperature of the CO 2 -containing mixed gas is 40 to 120 °C, preferably 60 to 80 °C.

[0039] In the present invention, when the CO 2 -containing mixed gas is the gas obtained by the flue gas capture and separation process, heat supplement treatment can be carried out (for example, using the plant area flue gas to exchange heat with the CO 2 -containing mixed gas, and then heating the CO 2 -containing mixed gas), so that the temperature of the CO 2 -containing mixed gas is 40 to 120 °C; when the CO 2 -containing mixed gas is the gas obtained after the flue gas is purified by dust removal, desulfurization and denitrification, the temperature of the CO 2 -containing mixed gas is within the range of 40 to 120 °C. When the temperature of the CO 2 -containing mixed gas is 40 to 120 °C, preferably 60 to 80 °C, the solubility of CO 2 in the wastewater can be increased.

[0040] According to the present invention, preferably, in step S1: the volume ratio range of the CO 2 -containing mixed gas to the high-salt industrial wastewater is 5:1 to 25:1, preferably 15:1 to 20:1.

[0041] According to the present invention, preferably, in step S1: the proportion range of the amount of the CO 2 -containing mixed gas fed into the first water tank and the second water tank through the micro-nano bubble generator is 1:1 to 1:10, preferably 1:4 to 1:6.

[0042] According to the present invention, preferably, in step S1: the turbidity of the slag-removed wastewater is monitored by the turbidity on-line detector, and by adjusting at least one of the dosage of the medicament, the intake air volume of the air inlet, the output power of the pressure regulator and the slag scraping device, the turbidity of the slag-removed wastewater is controlled to be less than 0.6 NTU.

[0043] In the present invention, the feeding amounts of the medicine adding port, the air inlet, the water inlet and the power frequency of the slag scraping device can be adjusted, so as to realize the matching of the amount of the high-salt industrial wastewater to be treated and the amount of the added medicament.

[0044] According to the present invention, preferably, in step S1: the pH of the effluent at the fresh water overflow is monitored by the on-line pH detector, and the pH of the effluent at the fresh water overflow is controlled to be less than 7 by adjusting the intake air volume of the air inlet and / or the proportion of CO 2 in the mixed gas containing CO 2 ; preferably, the proportion of CO 2 in the mixed gas containing CO 2 is in the range of 10%-80%, and more preferably 20%-40%.

[0045] In the present invention, the mixed gas containing CO 2 contains nitrogen, and the proportion of CO 2 in the mixed gas containing CO 2 can be adjusted by adjusting the proportion of nitrogen.

[0046] According to the present invention, preferably, in step S1: the capture and separation process is at least one of pressure swing adsorption, molecular sieve adsorption, organic amine adsorption and membrane separation, and preferably, the capture and separation process is pressure swing adsorption.

[0047] According to the present invention, preferably, in step S2: when the pressure difference measured by the differential pressure gauge in the security filter is ≥0.1 Mpa, preferably, when the pressure difference measured by the differential pressure gauge in the security filter is ≥0.15 Mpa, the detachable filter bag in the security filter is replaced.

[0048] In the present invention, the water quality of the wastewater after being treated by the security filter is consistent. The concentrated and fresh water flow distribution device is used to distribute the effluent after being treated by the security filter to the concentrated water inlet pipe and the fresh water inlet pipe. The concentrated and fresh water flow distribution device only controls the flow ratio of the concentrated water inlet and the fresh water inlet. According to the present invention, preferably, in step S2: the ratio of the fresh water inlet to the concentrated water inlet is 10:1 to 2:1, preferably 3:1 to 6:1.

[0049] According to the present invention, preferably, in step S2: the method further includes swapping the positions of the cathode and the anode. Preferably, the swapping time is determined according to the conductivity of the cathode chamber. More preferably, the swapping interval is 0.5-2 h.

[0050] In the present invention, by swapping the positive electrode and the negative electrode, the fresh water chamber and the concentrated water chamber in the membrane stack assembly can be swapped, thereby preventing the membrane stack on the concentrated water chamber side from scaling.

[0051] According to the present invention, preferably, in step S2: the electrode water is an aqueous NaCl solution with a concentration of 0.5-3%; the ratio of the electrode water to the fresh water inlet is 1:(8-15).

[0052] In the present invention, the polar water can wash away the OH enriched on the cathode surface due to concentration polarization - ions, avoid fouling (such as precipitation caused by the enrichment of OH - ions), and carry away other ions to avoid ion enrichment. In addition, it can also carry away the bubbles (such as O 2 , Cl 2 , H 2 , etc.) that may be produced during the electrolysis process of the cathode and anode, extend the service life of the electrode plates, and ensure long-term stable operation. In addition, the polar water also functions as an electrolyte, and the Na + ions and Cl - ions in the polar water migrate between the electrode plates, avoid the ionization of H 2 O, avoid the occurrence of concentration polarization, and slow down the enrichment of OH - ions on the electrode plates.

[0053] According to the present invention, preferably, in step S3: the method further includes sending a part of the concentrated water produced in the concentrated water tank as reflux concentrated water together with the concentrated water inlet water into the concentrated water chamber;

[0054] The amount of the reflux concentrated water is determined according to the conductivity of the water discharged at the concentrated water overflow port. Preferably, the ratio of the amount of the reflux concentrated water to the amount of the concentrated water inlet water is 1:1 to 10:1, preferably 3:1 to 5:1.

[0055] The beneficial effects of the technical solution of the present invention are as follows: The present invention solves the problems of blockage of the membrane stack by suspended impurities and blockage of the membrane stack by concentrated salt scale in the treatment of high-salt industrial wastewater in an integrated manner, utilizes CO 2 in the chemical process, realizes the resource utilization of CO 2 , and extends the efficient and stable operation time of the electrodialysis. Specifically:

[0056] 1. The present invention resourcefully utilizes the CO 2 in the plant flue gas, realizes carbon emission reduction of the plant flue gas while removing suspended impurities in the wastewater, increases the concentration of HCO 3 - in the wastewater, reduces the concentration of CO 3 2- , neutralizes the OH - generated by the polarization effect, reduces the pH of the wastewater, protects the membrane stack of the electrodialysis device, prevents the membrane stack from being blocked and scaled, realizes treating waste with waste, increases the efficient and stable operation time of the electrodialysis device at low cost, and improves the treatment capacity of the electrodialysis device;

[0057] 2. The present invention innovatively proposes a water tank structure, which can purify the wastewater, improve the treatment capacity of the electrodialysis subsystem and improve the current efficiency.

[0058] 3. The present invention improves the utilization efficiency of CO 2 and the treatment effect of wastewater through a micro-nano bubble generator.

[0059] 4. The present invention uses a mixed gas containing CO 2 to regulate the treatment of wastewater, maintains the pH of the wastewater, avoids the occurrence of events such as the damage of the electrodialysis membrane stack caused by fluctuations in the quality of the wastewater during the regulation process with acid solution, and improves the shock resistance of the electrodialysis device.

[0060] Other features and advantages of the present invention will be described in detail in the following specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] By describing the exemplary embodiments of the present invention in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present invention will become more apparent, wherein, in the exemplary embodiments of the present invention, the same reference numerals generally represent the same components.

[0062] Figure 1 FIG. 1 shows a schematic structural diagram of an anti-clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide provided in Embodiment 1 of the present invention.

[0063] Figure 2 FIG. 2 shows a schematic diagram of the principle of the membrane stack assembly and the electrode device of an anti-clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide provided by the present invention.

[0064] FIG. 3(a) shows the change in the fresh water recovery rate of wastewater treatment in Embodiment 1 of the present invention and Comparative Example 2 (in FIG. 3(a), "40% CO 2 60°C" is Embodiment 1, and "mixed gas without CO 2 " is Comparative Example 2).

[0065] FIG. 3(b) shows the change in the desalination rate of wastewater treatment in Embodiment 1 of the present invention and Comparative Example 2.

[0066] FIG. 3(c) shows the change in the current efficiency of wastewater treatment in Embodiment 1 of the present invention and Comparative Example 2.

[0067] FIG. 3(d) shows the change and fluctuation of the pH in the initial water quality of the wastewater before treatment in Embodiment 1 of the present invention and Comparative Example 3.

[0068] FIG. 3(e) shows the change and fluctuation of the total hardness in the initial water quality of the wastewater before treatment in Embodiment 1 of the present invention and Comparative Example 3.

[0069] FIG. 3(f) shows the change and fluctuation of the total alkalinity in the initial water quality of the wastewater before treatment in Embodiment 1 of the present invention and Comparative Example 3.

[0070] Figure 3(g) shows the change in the desalination rate of the wastewater treatment in Example 1 and Comparative Example 3 of the present invention (in Figure 3(g), " 2 mixed gas" is Example 1, and "hydrochloric acid solution" is Comparative Example 3).

[0071] The description of the reference numerals is as follows:

[0072] CM: Cation exchange membrane; AM: Anion exchange membrane;

[0073] 1 First water tank, 2 Second water tank, 3 Micro-nano bubble generator, 4 Scum scraping device, 5 Effluent overflow weir, 6 Air inlet, 7 Water inlet, 8 Water inlet pipe, 9 Chemical dosing port, 10 Slag discharge port, 11 Freshwater overflow port, 12 Outlet pipe, 13 Slag discharge overflow weir, 14 Baffle;

[0074] 15 Security filter, 16 Polar water tank, 17 Concentrate water inlet pipe, 18 Freshwater inlet pipe, 19 Polar water outlet pipe, 20 Polar water inlet pipe;

[0075] 21 Cathode, 22 Anode, 23 Concentrate water production pipe, 24 Concentrate water overflow port, 25 Concentrate water tank, 26 Freshwater production pipe, 27 Concentrate water return pipe, 28 Control valve. Detailed implementation manners

[0076] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0077] In the following Example 1:

[0078] The coagulant was purchased from Hubei Shishun Biotech Co., Ltd., CAS number: 26062-79-3;

[0079] The flocculant was purchased from Hubei Chengfeng Chemical Co., Ltd., CAS number: 9003-04-7;

[0080] The scale inhibitor was purchased from Chongqing Ruiya Biotech Co., Ltd., model BF-108;

[0081] In the following Example 2:

[0082] The coagulant was purchased from Shanghai Jiejing Chemical Co., Ltd., model: PAC;

[0083] The flocculant was purchased from Shandong Yonglida New Material Technology Co., Ltd., CAS number: 9003-05-8;

[0084] The scale inhibitor was purchased from Chongqing Ruiya Biotechnology Co., Ltd., model BF-108;

[0085] In Example 3 below:

[0086] The coagulant was purchased from Hubei Shishun Biotechnology Co., Ltd., CAS number: 26062-79-3;

[0087] The flocculant was purchased from Hubei Yongkuo Technology Co., Ltd., CAS number: 26590-05-06;

[0088] The scale inhibitor was purchased from Hubei Xinrunde Chemical Industry Co., Ltd., CAS number: 1429-50-1.

[0089] Example 1

[0090] This example provides a clogging-proof electrodialysis wastewater treatment system for the resource utilization of carbon dioxide. As Figure 1 shown, the system includes an inlet water subsystem, a security subsystem, and an electrodialysis subsystem;

[0091] The inlet water subsystem includes a first water tank 1, a second water tank 2, a micro-nano bubble generator 3, and a slag scraping device 4; the first water tank 1 and the second water tank 2 are connected in the upper part; the micro-nano bubble generator 3 is arranged at the bottoms of the first water tank 1 and the second water tank 2 for generating bubbles containing CO 2 and introducing the bubbles into the first water tank 1 and the second water tank 2. The inlet water subsystem further includes an air inlet 6, which is connected to the micro-nano bubble generator; the slag scraping device 4 is arranged above the first water tank 1 for scraping suspended impurities in the water; a slag discharge port 10 is arranged in the upper part of the first water tank 1, and a water inlet pipe 8 is connected to the lower part of the first water tank 1, and a chemical dosing port 9 is arranged on the water inlet pipe 8; the first water tank 1 is provided with a first side wall and a second side wall, and a slag discharge overflow weir 13 and a water outlet overflow weir 5 are respectively arranged on the upper parts of the first side wall and the second side wall. The first water tank 1 is connected to the second water tank 2 through the water outlet overflow weir 5, the slag discharge overflow weir 13 is arranged close to the slag discharge port 10, and a water inlet 7 is arranged at the lower part of the first side wall and is connected to the water inlet pipe 8;

[0092] A fresh water overflow port 11 is arranged on the upper part of one side wall of the second water tank 2 relative to the first water tank 1; a water outlet pipe 12 is connected to the bottom of the second water tank 2;

[0093] Moreover, a turbidity on-line detector (not shown) is provided at the water outlet overflow weir 5; the micro-nano bubble generator 3 is equipped with a pressure regulator; a slag discharge overflow weir 13 is provided at the slag discharge port 10; a pH on-line detector and a first conductivity on-line monitor are provided at the fresh water overflow port 11; a baffle plate 14 is arranged inside the second water tank 2 for separating the drainage from the first water tank 1 and the drainage from the fresh water production pipe 26; a water outlet flow regulating device is arranged on the water outlet pipe 12.

[0094] The security subsystem includes a security filter 15 and an electrodeionization water tank 16; the water outlet pipe 12 is connected to the water inlet end of the security filter 15. A detachable filter bag and a differential pressure gauge are arranged inside the security filter 15, and the filtration size of the detachable filter bag is 20 μm; a concentrated and fresh water flow distribution device is arranged between the detachable filter bag and the water outlet end of the security filter 15. The water outlet end of the security filter 15 is connected with a concentrated water inlet pipe 17 and a fresh water inlet pipe 18. The concentrated and fresh water flow distribution device is used to distribute the water filtered by the detachable filter bag to the concentrated water inlet pipe 17 and the fresh water inlet pipe 18; the electrodeionization water tank 16 is provided with an electrodeionization water outlet pipe 19 and an electrodeionization water inlet pipe 20.

[0095] The electrodialysis subsystem includes a membrane stack assembly and an electrode device; the electrode device includes 6 pairs of electrode pairs of transformable cathodes 21 and anodes 22, and a DC power supply; the membrane stack assembly is arranged between the cathode and the anode of each pair of electrode pairs and between adjacent electrode pairs; each membrane stack assembly is provided with 8 cation exchange membranes CM and 7 anion exchange membranes AM. The cation exchange membranes and the anion exchange membranes are arranged alternately, and the adjacent anion exchange membrane and cation exchange membrane form adjacent fresh water chambers and concentrated water chambers; the concentrated water inlet pipe 17 is used to send the concentrated water inlet of the security filter into the concentrated water chamber, and the concentrated water chamber is connected with a concentrated water tank 25 provided with a concentrated water overflow port 24 through a concentrated water production pipe 23; the fresh water inlet pipe 18 is used to send the fresh water inlet of the security filter into the fresh water chamber, and the fresh water chamber is connected with the second water tank 2 through a fresh water production pipe 26; the side of the cathode adjacent to the membrane stack assembly and the membrane stack assembly form a cathode chamber, and the side of the anode adjacent to the membrane stack assembly and the membrane stack assembly form an anode chamber. As Figure 2 shown, in this embodiment, the cathode and the adjacent cation exchange membrane form a cathode chamber; the anode and the adjacent cation exchange membrane form an anode chamber. A second conductivity on-line monitor is arranged in the cathode chamber; the electrodeionization water outlet pipe 19 and the electrodeionization water inlet pipe 20 are used to realize the circulating flow of the electrodeionization water in the electrodeionization water tank 16 between the cathode chamber and the electrodeionization water tank 16, and between the anode chamber and the electrodeionization water tank 16;

[0096] One side wall bottom of the concentrated water tank 25 is connected with a concentrated water return pipe 27, and the concentrated water return pipe 27 is used to send the concentrated water production of the concentrated water tank 25 and the concentrated water inlet of the security filter 15 into the concentrated water chamber together with the concentrated water inlet pipe 17 respectively; a regulating valve 28 is arranged on the concentrated water return pipe 27; a third on-line conductivity monitor is arranged at the concentrated water overflow port 24.

[0097] This embodiment also provides a method for preventing blockage and electro-dialysis wastewater treatment for resource utilization of carbon dioxide. The method uses the above system, and the wastewater treated by the method is high-salt organic wastewater generated by a chemical enterprise in the production of polyvinyl alcohol products. The water quality is as follows: pH is 8.45, conductivity is 2620 μs / cm, total hardness is 202 mg / L, total alkalinity is 386 mg / L, TDS is 1066 mg / L, COD is 32 mg / L, TOC is 6.68 mg / L, and turbidity is 1.56 NTU.

[0098] The method includes the following steps:

[0099] S1: Send the above high-salt industrial wastewater and medicaments (composed of 3 ppm of coagulant, 200 ppm of flocculant, and 1 ppm of scale inhibitor) into the first water tank through the water inlet pipe 8 and the medicine adding port 9 respectively; send the mixed gas containing CO 2 (the proportion of CO 2 is 40%, the temperature is 60 °C, and the gas is obtained by the pressure swing adsorption process of flue gas) into the first water tank 1 and the second water tank 2 through the micro-nano bubble generator 3 to form bubbles (the ratio of the amount of the mixed gas containing CO 2 in the first water tank and the second water tank is 1:5). Among them, the volume ratio of the mixed gas containing CO 2 and the high-salt industrial wastewater is 16:1. Adjust the pressure regulator of the micro-nano bubble generator to control the bubble size to be 40 μm; above the first water tank 1, use the slag scraping device to discharge the scum, suspended impurities and foam in the first water tank out of the system through the slag discharge port 10 (control the turbidity of the slag-removed wastewater by regulating the output power of the slag scraping device), obtain the slag-removed wastewater and enter the second water tank through the water outlet overflow weir 5;

[0100] S2: Send the slag-removed wastewater in the second water tank into the security filter 15 through the water outlet pipe 12 for filtration (use the water flow regulating device arranged at the water outlet pipe 12 to regulate the water flow of the water outlet pipe 12 to be 2 times the overflow flow rate from the first water tank to the second water tank). Specifically: the second water tank is divided into left and right two areas by the intermediate partition board. The area close to the first water tank (the left area) is mainly the drainage of the first water tank (i.e., the slag-removed wastewater), and it is supplemented with CO by the lower micro-nano bubble generator2 Adjust the pH value, and then enter the security filter from the bottom of the left area of the second water tank; the drainage from the fresh water production pipe enters the right area of the second water tank from the upper part of the right area, and undergoes multiple electrodialysis cycles together with the water to be entered into the electrodialysis subsystem at the bottom of the second water tank. The fresh water overflow port is also in the upper part of the right area. The treated drainage from the fresh water production pipe overflows and is recycled through the fresh water overflow port. Moreover, the flow rate of the water outlet pipe at the bottom of the second water tank is greater than the overflow flow rate from the first water tank to the second water tank, realizing multiple cycle treatments of the wastewater and improving the treatment effect. At the same time, the fresh water production pipe enters the second water tank at the upper right part of the second water tank, avoiding mixing with the wastewater that has not been treated by the second water tank and overflowed from the first water tank to the second water tank. The drainage from the fresh water production pipe only mixes with the treated wastewater in the second water tank, ensuring the treatment effect of the fresh water overflowed and recycled from the upper right fresh water overflow port;

[0101] The turbidity of the water in the water outlet pipe 12 is 0.25 NTU, the pH reaches 6.82, and the CO utilization efficiency in the gas is 41.4%; 2 The utilization efficiency is 41.4%;

[0102] Use the concentrated and fresh water flow distribution device to distribute the water flow at the water outlet end of the security filter 15 to obtain concentrated water inlet and fresh water inlet. The water quality of the concentrated water inlet and the fresh water inlet is the same, only the flow rates are different, and the flow rate ratio is fresh water inlet: concentrated water inlet = 5:1; send the concentrated water inlet and the fresh water inlet into the concentrated water chamber and the fresh water chamber respectively for electrodialysis treatment (110V direct current), and interchange the cathode 21 and the anode 22 every 1 h; at the same time, use the electrode water outlet pipe 19 and the electrode water inlet pipe 20 to make the electrode water in the electrode water tank 16 (the electrode water is a 1% concentration NaCl aqueous solution; the ratio of the electrode water to the fresh water inlet is 1:10) circulate between the cathode chamber and the electrode water tank 16 and between the anode chamber and the electrode water tank 16 to protect the membrane stack;

[0103] S3: Obtain concentrated water production in the concentrated water chamber and send it into the concentrated water tank 25 through the concentrated water production pipe 23. Take part of the concentrated water production in the concentrated water tank 25 as the reflux concentrated water and send it into the concentrated water chamber together with the concentrated water inlet, adjust the regulating valve 28, and control the ratio of the amount of the reflux concentrated water to the amount of the concentrated water inlet to be 3:1; the remaining part of the concentrated water production in the concentrated water tank 25 is used as a salt resource and is recycled through the concentrated water overflow port 24; obtain fresh water production in the fresh water chamber and send it into the second water tank 2 through the fresh water production pipe 26, and recycle the fresh water resource through the fresh water overflow port 11.

[0104] After the system operates stably for 2 h: the conductivity reaches 667 μs / cm, the TDS reaches 298 mg / L, the total alkalinity reaches 45 mg / L, and the total hardness reaches 15 mg / L;

[0105] The conductivity of the effluent from the concentrated water overflow port 24 reaches 11663 μs / cm, the TDS reaches 4822 mg / L, the total alkalinity reaches 1088 mg / L, and the total hardness reaches 336 mg / L;

[0106] In this embodiment, the fresh water recovery rate after wastewater desalination treatment is 86.2%, the desalination rate is 74.5%, and the system current efficiency is 72.2%.

[0107] Example 2

[0108] This embodiment provides a method for preventing blockage in electrodialysis wastewater treatment for resource utilization of carbon dioxide. The method uses the system of Example 1, and the wastewater to be treated is high-salt organic wastewater produced by a certain refining enterprise. The water quality is as follows: pH is 7.32, conductivity is 1236 μs / cm, total hardness is 96 mg / L, total alkalinity is 117 mg / L, TDS is 525 mg / L, COD is 37 mg / L, TOC is 12 mg / L, and turbidity is 2.45 NTU;

[0109] The method includes the following steps:

[0110] S1: Feed the high-salt industrial wastewater of this embodiment and the medicament (composed of 4 ppm of coagulant, 220 ppm of flocculant, and 0.3 ppm of scale inhibitor) into the first water tank through the water inlet pipe 8 and the chemical dosing port 9 respectively; Feed the mixed gas containing CO 2 (the proportion of CO 2 is 30%, the temperature is 65 °C, and it is the gas obtained by the pressure swing adsorption process of flue gas) into the first water tank 1 and the second water tank 2 through the micro-nano bubble generator 3 to form bubbles (the ratio of the amount of the mixed gas containing CO 2 in the first water tank and the second water tank is 1:4). Among them, the volume ratio of the mixed gas containing CO 2 and the high-salt industrial wastewater is 15:1. Adjust the pressure regulator of the micro-nano bubble generator to control the bubble size to be 25 μm; Above the first water tank 1, use the slag scraping device to discharge the scum, suspended impurities, and foam in the first water tank out of the system through the slag discharge port 10 (by regulating the output power of the slag scraping device, control the turbidity of the wastewater after slag removal), obtain the wastewater after slag removal and enter the second water tank through the water outlet overflow weir 5;

[0111] S2: Feed the waste water with residues removed in the second water tank into the security filter 15 through the water outlet pipe 12 (regulate the water flow rate of the water outlet pipe 12 to 1.5 times the overflow flow rate from the first water tank to the second water tank by using the water flow rate regulating device provided at the water outlet pipe 12). Specifically: The second water tank is divided into left and right areas by a baffle plate in the middle. The area near the first water tank (left area) is mainly the drainage from the first water tank (i.e., the waste water with residues removed), which is affected by the pH adjustment of CO 2 fed in by the micro-nano bubble generator at the lower part, and then enters the security filter from the bottom of the left area of the second water tank; The drainage from the fresh water production pipe enters the right area of the second water tank from the upper part of the right area, and undergoes electro-dialysis circulation treatment multiple times together with the water in the bottom of the second water tank to be fed into the electro-dialysis subsystem. The fresh water overflow port is also in the upper part of the right area. The drainage after multiple treatments from the fresh water production pipe overflows and is recycled through the fresh water overflow port. Moreover, the flow rate of the water outlet pipe at the bottom of the second water tank is greater than the overflow flow rate from the first water tank to the second water tank, realizing multiple cycle treatments of the waste water and improving the treatment effect. At the same time, the fresh water production pipe enters the second water tank at the upper right part of the second water tank, avoiding mixing with the waste water that has not been treated by the second water tank and overflowed from the first water tank to the second water tank. The drainage from the fresh water production pipe only mixes with the waste water treated by the second water tank, ensuring the treatment effect of the fresh water overflowed and recycled from the fresh water overflow port at the upper right part;

[0112] The turbidity of the water in the water outlet pipe 12 is 0.33 NTU, the pH reaches 6.35, and the utilization efficiency of CO 2 in the gas is 38.6%;

[0113] Use the concentrated and fresh water flow rate distribution device to distribute the water flow rate at the water outlet end of the security filter 15 to obtain concentrated water inlet and fresh water inlet. The water quality of the concentrated water inlet and the fresh water inlet is the same, only the flow rates are different, and the flow rate ratio is fresh water inlet: concentrated water inlet = 6:1; Feed the concentrated water inlet and the fresh water inlet into the concentrated water chamber and the fresh water chamber respectively for electro-dialysis treatment (100 V direct current), and interchange the cathode 21 and the anode 22 every 40 minutes; At the same time, use the electrode water outlet pipe 19 and the electrode water inlet pipe 20 to make the electrode water in the electrode water tank 16 (the electrode water is a 1.5% concentration NaCl aqueous solution; the ratio of the electrode water to the fresh water inlet is 1:10) circulate between the cathode chamber and the electrode water tank 16 and between the anode chamber and the electrode water tank 16 to protect the membrane stack;

[0114] S3: Obtain concentrated water product in the concentrated water chamber and send it into the concentrated water tank 25 through the concentrated water product pipe 23. Take a part of the concentrated water product in the concentrated water tank 25 as the reflux concentrated water and send it into the concentrated water chamber together with the concentrated water inlet. Adjust the regulating valve 28 to control the ratio of the amount of the reflux concentrated water to the amount of the concentrated water inlet to be 4:1. The remaining part of the concentrated water product in the concentrated water tank 25 is taken as salt resources and recovered through the concentrated water overflow port 24. Obtain fresh water product in the fresh water chamber and send it into the second tank 2 through the fresh water product pipe 26, and recover fresh water resources through the fresh water overflow port 11.

[0115] After the system operates stably for 2 h: the conductivity reaches 217 μs / cm, the TDS reaches 108 mg / L, the total alkalinity reaches 12 mg / L, and the total hardness reaches 17 mg / L.

[0116] The conductivity of the water discharged from the concentrated water overflow port 24 reaches 4575 μs / cm, the TDS reaches 1936 mg / L, the total alkalinity reaches 447 mg / L, and the total hardness reaches 235 mg / L.

[0117] In this embodiment, the fresh water recovery rate after the desalination treatment of the wastewater is 82.6%, the desalination rate is 80.5%, and the system current efficiency is 76.3%.

[0118] Embodiment 3

[0119] This embodiment provides a method for treating electroosmotic desalination wastewater with anti-blocking and resource utilization of carbon dioxide. The difference between the system adopted by this method and that of Embodiment 1 is only that: the filter bag size of the detachable filter bag is 5 μm, and the wastewater treated by this method is high-salt organic wastewater produced by a certain refinery enterprise, and the water quality is as follows: pH is 7.26, conductivity is 1775 μs / cm, total hardness is 126 mg / L, total alkalinity is 223 mg / L, TDS is 675 mg / L, COD is 55 mg / L, TOC is 17 mg / L, and turbidity is 2.98 NTU.

[0120] The method includes the following steps:

[0121] S1: Send the high-salt industrial wastewater of this embodiment and the medicament (composed of 5 ppm of coagulant, 250 ppm of flocculant, and 0.5 ppm of scale inhibitor) into the first tank through the water inlet pipe 8 and the chemical dosing port 9 respectively. Send the mixed gas containing CO 2 (the proportion of CO 2 is 20%, the temperature is 60 °C, and it is the gas obtained by the pressure swing adsorption process of the flue gas) into the first tank 1 and the second tank 2 through the micro-nano bubble generator 3 to form bubbles (the ratio of the amount of the mixed gas containing CO 2 in the first tank and the second tank is 1:6), where the mixed gas containing CO2 The volume ratio of the mixed gas to the high-salt industrial wastewater is 20:1. Adjust the pressure regulator of the micro-nano bubble generator to control the bubble size to 30 μm. Above the first water tank 1, the scum, suspended impurities, and foam in the first water tank are discharged from the system through the slag discharge port 10 by the slag scraping device (by regulating the output power of the slag scraping device, controlling the turbidity of the slag-removed wastewater), and the slag-removed wastewater is obtained and enters the second water tank through the water outlet overflow weir 5;

[0122] S2: Feed the slag-removed wastewater in the second water tank into the security filter 15 through the water outlet pipe 12 for filtration (using the water flow regulating device provided at the water outlet pipe 12 to regulate the water flow rate of the water outlet pipe 12 to 1.5 times the overflow flow rate from the first water tank to the second water tank). Specifically: The second water tank is divided into left and right two regions by the intermediate partition plate. The region close to the first water tank (left region) is mainly the drainage of the first water tank (i.e., the slag-removed wastewater), which is affected by the pH adjustment of CO 2 and then enters the security filter from the bottom of the left region of the second water tank; The drainage from the fresh water production pipe enters the right region of the second water tank from the upper part of the right region, and is subjected to multiple electrodialysis cycles together with the water to be entered into the electrodialysis subsystem at the bottom of the second water tank. The fresh water overflow port is also in the upper part of the right region, and the treated drainage from the fresh water production pipe is overflowed and recycled through the fresh water overflow port. Moreover, the flow rate of the water outlet pipe at the bottom of the second water tank is greater than the overflow flow rate from the first water tank to the second water tank, realizing the multiple cycle treatment of the wastewater and improving the treatment effect. At the same time, the fresh water production pipe enters the second water tank at the upper right part of the second water tank, avoiding mixing with the wastewater that has not been treated by the second water tank and overflowed from the first water tank to the second water tank. The drainage from the fresh water production pipe only mixes with the wastewater treated by the second water tank, ensuring the treatment effect of the fresh water overflowed and recycled from the fresh water overflow port at the upper right part;

[0123] The turbidity of the water in the water outlet pipe 12 is 0.52 NTU, the pH reaches 6.56, and the utilization efficiency of CO 2 in the gas is 31.3%;

[0124] Use the concentrated and fresh water flow distribution device to distribute the water flow at the water outlet end of the security filter 15 to obtain concentrated water inlet and fresh water inlet. The water quality of the concentrated water inlet and the fresh water inlet is the same, only the flow rates are different, and the flow rate ratio is fresh water inlet: concentrated water inlet = 3:1. Feed the concentrated water inlet and the fresh water inlet into the concentrated water chamber and the fresh water chamber respectively for electrodialysis treatment (100V direct current), and exchange the positions of the cathode 21 and the anode 22 every 40 minutes. At the same time, use the electrode water outlet pipe 19 and the electrode water inlet pipe 20 to make the electrode water in the electrode water tank 16 (the electrode water is a 2% concentration NaCl aqueous solution; the ratio of the electrode water to the fresh water inlet is 1:10) circulate between the cathode chamber and the electrode water tank 16, and between the anode chamber and the electrode water tank 16 to protect the membrane stack.

[0125] S3: Obtain concentrated water production in the concentrated water chamber and send it into the concentrated water tank 25 through the concentrated water production pipe 23. Take part of the concentrated water production in the concentrated water tank 25 as the recycled concentrated water and send it into the concentrated water chamber together with the concentrated water inlet. Adjust the regulating valve 28 to control the ratio of the amount of the recycled concentrated water to the amount of the concentrated water inlet to be 5:1. The remaining part of the concentrated water production in the concentrated water tank 25 is taken as salt resources and recovered through the concentrated water overflow port 24. Obtain fresh water production in the fresh water chamber and send it into the second water tank 2 through the fresh water production pipe 26, and recover fresh water resources through the fresh water overflow port 11.

[0126] After the system runs stably for 2 hours: the conductivity reaches 388 μs / cm, the TDS reaches 178 mg / L, the total alkalinity reaches 33 mg / L, and the total hardness reaches 12 mg / L.

[0127] The conductivity of the water discharged from the concentrated water overflow port 24 reaches 6632 μs / cm, the TDS reaches 2533 mg / L, the total alkalinity reaches 806 mg / L, and the total hardness reaches 252 mg / L.

[0128] In this embodiment, the fresh water recovery rate after wastewater desalination treatment is 75%, the desalination rate is 78.1%, the COD degradation rate is 52.7%, and the system current efficiency is 76.3%.

[0129] Example 4

[0130] This embodiment provides a method for preventing blockage of electrodialysis wastewater treatment for resource utilization of carbon dioxide. The difference between this method and that of Example 1 is only that: the proportion of CO in the mixed gas containing CO 2 is 36%, and the temperature is 70 °C. 2

[0131] After the system runs stably for 2 hours: the turbidity of the water in the water outlet pipe 12 reaches 0.23 NTU, the pH reaches 6.22, and CO in the gas 2The utilization efficiency is 44.2%. In this embodiment, the fresh water recovery rate after wastewater desalination treatment reaches 87.2%, the desalination rate reaches 82.3%, and the current efficiency of the device is 76.1%.

[0132] Example 5

[0133] This embodiment provides a method for preventing clogging of electrodialysis wastewater treatment for resource utilization of carbon dioxide. The difference between this method and that of Example 1 is only that: in the mixed gas containing CO 2 the proportion of CO 2 is 29%, and the temperature is 65 °C.

[0134] After the system operates stably for 2 h: the turbidity of the water in the water outlet pipe 12 reaches 0.32 NTU, the pH reaches 6.85, and the utilization efficiency of CO 2 in the gas is 39.2%. In this embodiment, the fresh water recovery rate after wastewater desalination treatment reaches 86.5%, the desalination rate reaches 80.2%, and the current efficiency of the device is 71.7%.

[0135] Example 6

[0136] This embodiment provides a method for preventing clogging of electrodialysis wastewater treatment for resource utilization of carbon dioxide. The difference between this method and that of Example 1 is only that: in the mixed gas containing CO 2 the proportion of CO 2 is 23%, and the temperature is 62 °C.

[0137] After the system operates stably for 2 h: the turbidity of the water in the water outlet pipe 12 reaches 0.35 NTU, the pH reaches 6.97, and the utilization efficiency of CO 2 in the gas is 33.6%. In this embodiment, the fresh water recovery rate after wastewater desalination treatment reaches 85.7%, the desalination rate reaches 73.6%, and the current efficiency of the device is 70.8%.

[0138] Examples 7 - 16

[0139] The difference between Examples 7 - 16 and Example 1 is only that: the proportion of CO 2 in the mixed gas containing CO 2 is different. (By adjusting the proportion of nitrogen in the mixed gas containing CO 2 the proportion of CO 2 in the mixed gas containing CO 2 is adjusted)

[0140] Compare the treatment effects corresponding to the continuous operation of the systems of Examples 7 - 16 and Example 1 for 2 h, as shown in Table 1.

[0141] Table 1

[0142]

[0143]

[0144] It can be found from the comparison table 1 that:

[0145] When the CO 2 content in the mixed gas used is 20-40%, the process of the present invention operates excellently, showing a high fresh water recovery rate, a high desalination rate and a high current efficiency.

[0146] When the CO 2 proportion is lower than 20%, it is measured that the pH of the water in the outlet pipe 12 of the second water tank is on the high side, and the turbidity, total alkalinity and total hardness are on the high side, indicating that the CO 2 content is insufficient, the total alkalinity and total hardness in the wastewater are not removed thoroughly, resulting in a large load on the electrodialysis membrane stack assembly and an increase in the blockage frequency, resulting in a significant decline in the effect after 2 hours of continuous operation.

[0147] When the CO 2 proportion is higher than 40%, it is measured that the pH of the water in the outlet pipe 12 of the second water tank is on the low side, and the contents of carbonate ions and bicarbonate ions in the wastewater are high, increasing the load on the membrane stack during the electrodialysis operation and reducing the current efficiency during the operation, resulting in a decline in the desalination rate and fresh water recovery rate of the wastewater.

[0148] It can be seen from this that by controlling the CO 2 concentration (i.e., proportion) in the mixed gas used, the treatment effects of the first water tank and the second water tank on the wastewater can be significantly improved, and the treatment effect and current efficiency of the electrodialysis can be improved.

[0149] Examples 17-27

[0150] The difference between Examples 17-27 and Example 1 is only that: the temperature of the CO 2 -containing mixed gas is different.

[0151] Compare the treatment effects corresponding to the continuous operation of the systems of Examples 17-27 and Example 1 for 2 hours, as shown in Table 2.

[0152] Table 2

[0153]

[0154] It can be found from the comparison of Table 2 that:

[0155] When the temperature of the mixed gas is 60-80 °C, the system of the present invention operates excellently, maintaining a high CO 2 utilization efficiency and high fresh water recovery rate, desalination rate and current efficiency.

[0156] When the temperature of the mixed gas is lower than 60°C, the temperature is relatively low, and the utilization efficiency of CO 2 decreases. After measurement, the pH of the water in the outlet pipe 12 of the second water tank is on the high side, and the turbidity, total alkalinity, and total hardness are on the high side, resulting in a relatively large membrane stack pressure in the electrodialysis system and a reduced operation effect;

[0157] When the temperature of the mixed gas is higher than 80°C, the temperature is relatively high, and the utilization efficiency of CO 2 is relatively high, but it causes the temperature of the water in the outlet pipe 12 of the second water tank to rise. During the operation of the electrodialysis subsystem, the stability and performance of the membrane stack are affected, reducing the ion permeability of the membrane stack during the operation of electrodialysis, reducing the desalination rate and current efficiency of the electrodialysis system, resulting in a decrease in efficiency and an increase in energy consumption.

[0158] Through the above comparison, it can be clarified that controlling the temperature of the CO 2 -containing mixed gas can effectively improve the operation effect of the electrodialysis system.

[0159] Examples 28 - 40

[0160] The difference between Examples 28 - 40 and Example 1 is only that: the diameter of the bubbles is different (by adjusting the pressure regulator of the micro-nano bubble generator).

[0161] Compare the treatment effects corresponding to the continuous operation of the systems of Examples 28 - 40 and Example 1 for 2 hours, as shown in Table 3.

[0162] Table 3

[0163]

[0164]

[0165] It is found by comparing Table 3 that:

[0166] When the bubble size of the present invention is between 20 - 40 μm, under the operating conditions of maintaining a fresh water recovery rate of about 86% (85.8% - 86.3%), a desalination rate higher than 74% and a current efficiency higher than 72% can be achieved.

[0167] When the bubble size is less than 20 μm, due to the small bubble size, the CO 2 -containing mixed gas stays in the first water tank and the second water tank for a long time. Although the CO 2The utilization efficiency is improved. However, the bubbles are in a suspended state in the wastewater, with a too long residence time and small bubbles, resulting in small sediment particles generated by flocculation precipitation being difficult to be captured and floated by the bubbles. The slag scraping device has a reduced ability to remove solid suspended matter, leading to an increased load on the electrodialysis membrane stack. As a result, during the operation of the electrodialysis, under the condition of a freshwater recovery rate of about 86%, the desalination rate is reduced to below 70.5%, reaching a minimum of 58.4%, and the current efficiency is lower than 70%, reaching a minimum of 56.7%, and the operation effect is significantly reduced.

[0168] When the bubble size is higher than 40 μm, due to the inclusion of CO 2 The residence time of the mixed gas in the wastewater of the first water tank and the second water tank becomes shorter, resulting in a decrease in the utilization efficiency of CO 2 The pH of the water in the outlet pipe 12 of the second water tank increases, and the removal rates of Ca 2+ and Mg 2+ decrease, leading to an increased load on the electrodialysis membrane stack and an accelerated blocking of the membrane stack. As a result, during the continuous operation of the electrodialysis for 2 h, under the working condition of a freshwater recovery rate of about 86%, the desalination rate is lower than 72%, reaching a minimum of 553%, and the current efficiency is lower than 70%, reaching a minimum of 51.5%.

[0169] The above results intuitively show that controlling the average size of the bubbles generated by the micro-nano bubble generator can strengthen the regulation of the pH, total hardness, and total alkalinity of the wastewater by the CO 2 mixed gas in the first water tank and the second water tank of the system and method of the present invention, prevent the blocking of the electrodialysis membrane stack, and optimize the operation effect of the electrodialysis device.

[0170] Examples 41 - 49, Comparative Example 1

[0171] The differences between Examples 41 - 49, Comparative Example 1 and Example 1 are only as follows: the volume ratios of the CO 2 -containing mixed gas and the high-salt industrial wastewater are different.

[0172] Under the working condition of maintaining a freshwater recovery rate of 86.2%, the treatment effects corresponding to the continuous operation of 6 h of the systems of Examples 41 - 49, Comparative Example 1 and Example 1 are compared, as shown in Table 4.

[0173] Table 4

[0174]

[0175] * The freshwater recovery rate of the electrodialysis is 86.2%

[0176] The results in Table 4 intuitively show that:

[0177] In Comparative Example 1, the CO 2When mixing gases, the NTU and pH of the water in the outlet pipe 12 of the second water tank are both relatively high. Even under operating conditions where the fresh water recovery rate is lower than 70%, the electrodialysis operation effect deteriorates significantly.

[0178] However, after using the mixed gas containing CO 2 the water quality in the outlet pipe 12 of the second water tank is significantly purified, and the electrodialysis operation effect is enhanced.

[0179] Especially when the volume ratio of the mixed gas containing CO 2 and the high-salt industrial wastewater ranges from 15:1 to 20:1, the NTU in the water in the outlet pipe 12 of the second water tank is maintained below 0.26, and the pH remains between 6.5 and 7. The system and process of the present invention show optimal performance, and a desalination rate higher than 73% and a current efficiency higher than 70% are achieved after continuous operation for 6 hours.

[0180] When the volume ratio of the mixed gas containing CO 2 and the high-salt industrial wastewater is higher than 20:1, the NTU of the water in the outlet pipe 12 of the second water tank is further purified, but the effect is not significant, and the pH is lower than 6.5. The concentrations of CO 3 2- and HCO 3 - in the wastewater increase, and the load on the electrodialysis membrane stack increases, resulting in a decrease in the desalination rate and current efficiency.

[0181] When the volume ratio of the mixed gas containing CO 2 and the high-salt industrial wastewater is lower than 15:1, due to insufficient gas volume, the NTU and pH of the water in the outlet pipe 12 of the second water tank are relatively high, the NTU is higher than 0.35, the pH is higher than 7, the water quality is poor, and the load on the electrodialysis membrane stack is relatively high, resulting in a decrease in the electrodialysis operation effect.

[0182] In summary, by adopting the system and process method of the present invention and comprehensively using the mixed gas containing CO 2 to treat wastewater, the load on the electrodialysis membrane stack can be significantly reduced, and the electrodialysis treatment effect and the temperature operation time can be improved.

[0183] Examples 50 - 58

[0184] The difference between Examples 50 - 58 and Example 1 is only that: the proportion of the amount of the mixed gas containing CO 2 fed into the first water tank and the second water tank is different.

[0185] Under the condition of maintaining a fresh water recovery rate of 86.2%, the treatment effects corresponding to the continuous operation of 2 hours of the systems in Examples 50 - 58 and Example 1 were compared, as shown in Table 5.

[0186] Table 5

[0187]

[0188]

[0189] It is found by comparing the results in Table 5 that:

[0190] In the present invention, regulating the proportion of the CO 2 mixed gas in the first water tank and the second water tank can significantly affect the wastewater treatment effect.

[0191] When the proportion of the CO 2 mixed gas in the first water tank and the second water tank is in the range of 1:4 to 1:6, the pH of the waste liquid in the first water tank remains relatively high and the bubbles are relatively dense. The removal effects of NTU and total hardness are good. The NTU of the water in the outlet pipe 12 of the second water tank is lower than 0.25, and the total hardness is lower than 65 mg / L. The corresponding load pressure of the electrodialysis membrane stack is small. The desalination rate can be maintained above 74.5% and the current efficiency is above 72% during continuous operation for 2 h.

[0192] When the proportion of the CO 2 mixed gas in the first water tank and the second water tank is in the range of 1:1 to 1:3, due to the relatively high content of the CO 2 mixed gas in the first water tank, the pH of the wastewater in the first water tank drops significantly, and the pH is lower than 8, which affects the removal effect of total hardness, resulting in the total hardness of the water in the outlet pipe 12 of the second water tank being higher than 75 mg / L, increasing the load of the electrodialysis membrane stack, and thus reducing the desalination rate and current efficiency during continuous operation for 2 h.

[0193] When the proportion of the CO 2 mixed gas in the first water tank and the second water tank is in the range of 1:7 to 1:10, due to the relatively low bubble concentration in the first water tank, the flocculation and the floating effect of the precipitate generated by calcium and magnesium ions become worse, and the pH of the wastewater in the first water tank is relatively high, weakening the effect of the flocculant, resulting in relatively high NTU and total hardness of the water in the outlet pipe 12 of the second water tank, increasing the operating load of the electrodialysis membrane stack structure, and thus reducing the desalination rate and current efficiency.

[0194] In summary, the system and process method of the present invention can regulate the appropriate proportion of the CO 2 mixed gas in the first water tank and the second water tank, optimize the removal effects of NTU and total hardness in the wastewater, reduce the load of the electrodialysis membrane stack, and thus improve the desalination rate and current efficiency of the electrodialysis device.

[0195] Comparative Example 2

[0196] Compared with Example 1, the operation process is the same, but without using the CO-containing 2The mixed gas and the first water tank, and the wastewater to be treated directly enters the second water tank. The changes in the fresh water recovery rate, desalination rate, and current efficiency after the desalination treatment of the wastewater in Comparative Example 2 and Example 1 are shown in Figures 3(a)-(b) below.

[0197] It can be found from Figure 3(a) that: The present invention uses a mixed gas containing CO 2 During continuous operation for 10 hours, the fresh water recovery rate remains above 80%. However, for the wastewater treated in Comparative Example 2, it directly enters the system from the second water tank, increasing the membrane stack load, resulting in a gradual decrease in the fresh water recovery rate during the 10-hour continuous operation, from 85% to 56.8%.

[0198] It can be found from Figure 3(b) that: The present invention co-treats wastewater by resourcefully utilizing the mixed gas containing CO 2 to reduce the pressure of the membrane stack components. During continuous operation for 8 hours, the desalination rate is higher than 70%, and during continuous operation for 10 hours, the desalination rate remains higher than 65%. However, in Comparative Example 2, without using the mixed gas containing CO 2 and under the operating conditions of the first water tank, the desalination rate gradually decreases from 76% to 50% within 3 hours of continuous operation of the device. Subsequently, during the next 6 hours of operation, due to fouling and blockage on the membrane stack, the desalination rate drops significantly to about 20%, and the quality of the electro-dialysis produced water is significantly reduced.

[0199] It can be found from Figure 3(c) that: Under the condition that the present invention uses the mixed gas containing CO 2 to co-treat wastewater through the first water tank, during the continuous operation for 10 hours, the electro-dialysis current efficiency remains above 60%, and during the first 7 hours of operation, the current efficiency can be maintained above 70%. However, in Comparative Example 2, without using the first water tank and under the operating conditions of the mixed gas containing CO 2 the electro-dialysis membrane stack quickly fouls, and the current efficiency drops rapidly within the first 4 hours of operation, from about 75% to below 25%. Subsequently, it maintains a relatively low current efficiency, resulting in an increase in the energy consumption of electro-dialysis.

[0200] Through the above comparison, it is found that the structural innovation of the first water tank and the second water tank of the present invention and the resourceful utilization of CO 2 to co-treat wastewater can significantly improve the treatment effect of electro-dialysis and reduce energy consumption, having significant advantages and application prospects.

[0201] Comparative Example 3

[0202] The difference between this comparative example and Example 1 is that: 5% hydrochloric acid solution is used to replace the mixed gas containing 40% CO 2 for pH adjustment in the first water tank and the second water tank.

[0203] Moreover, Comparative Example 3 and Example 1 were each continuously operated for 4 h and intermittently stopped for 5 min, and the membrane stack was backwashed and purified to remove the scale on the surface of the membrane stack. Within 100 h, the variation of pH, total alkalinity, and total hardness in the initial water quality of the wastewater before treatment in Comparative Example 3 and Example 1 is shown in Figures 3(d)-(f), and the variation of the desalination rate in Comparative Example 3 and Example 1 is shown in Figure (g).

[0204] It can be found from Figures 3(d)-(f) that there are fluctuations in the pH of the water coming from the process plant area, and the overall pH is in the range of 7.0 - 9.5. In the present invention, a mixed gas containing 40% CO 2 is used in the first water tank and the second water tank to reduce alkalinity and hardness, remove Ca 2+ and Mg 2+ , and regulate the pH value of the wastewater to reduce the blockage problem of the electrodialysis membrane stack. In Comparative Example 3, hydrochloric acid solution was added to keep the wastewater at a low pH to prevent the blockage of the electrodialysis membrane stack.

[0205] It can be seen from Figure 3(g) that the use of the mixed gas containing CO 2 in the present invention can significantly maintain the operation stability, and the electrodialysis desalination rate is maintained above 60%, with a high anti-fluctuation ability. In Comparative Example 3, the method of using hydrochloric acid solution to regulate the pH of the wastewater can only reduce the total alkalinity of the treated wastewater and cannot reduce the total hardness of the wastewater. When the pH of the wastewater decreases, the hydrochloric acid solution will regulate the wastewater to have a lower pH value, which is harmful to the membrane stack, resulting in a gradual decline in the electrodialysis treatment capacity during long-term operation, and the desalination efficiency is lower than 40% within 100 h of operation time.

[0206] Through the above comparison, it can be confirmed that the system and method of the present invention have higher anti-impact ability. The mixed gas containing CO 2 not only reduces the total alkalinity and total hardness of the wastewater, prevents the membrane stack from scaling, but also moderately adjusts the pH of the wastewater to offset the OH - generated by the concentration polarization of the membrane stack, and will not cause the pH of the wastewater to be too low, protecting the stable operation of the electrodialysis membrane stack.

[0207] The above has described the embodiments of the present invention. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments.

Claims

1. An anti-clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide, characterized in that, the system includes an inlet water subsystem, a security subsystem and an electrodialysis subsystem; The water inlet subsystem includes a first water tank, a second water tank, a micro-nano bubble generator, and a slag scraping device; the first water tank and the second water tank are communicated with each other at the upper part; the micro-nano bubble generator is arranged at the bottoms of the first water tank and the second water tank and is used for generating bubbles containing CO 2 and introducing the bubbles into the first water tank and the second water tank; the slag scraping device is arranged above the first water tank and is used for scraping suspended impurities in the water; a slag discharge port is arranged at the upper part of the first water tank, and a water inlet pipe is connected to the lower part of the first water tank, and a chemical dosing port is arranged on the water inlet pipe; a fresh water overflow port is arranged at the upper part of one side wall of the second water tank relative to the first water tank; a water outlet pipe is connected to the bottom of the second water tank; the security subsystem includes a security filter and an electrode water tank; the outlet pipe is connected to the inlet end of the security filter, and the outlet end of the security filter is connected with a concentrated water inlet pipe and a fresh water inlet pipe; the electrode water tank is provided with an electrode water outlet pipe and an electrode water inlet pipe; the electrodialysis subsystem includes a membrane stack assembly and an electrode device; the membrane stack assembly is alternately provided with a plurality of cation exchange membranes and anion exchange membranes, and the adjacent anion exchange membrane and cation exchange membrane form adjacent fresh water chambers and concentrated water chambers; the concentrated water inlet pipe is connected to the concentrated water chamber, and the concentrated water chamber is connected to a concentrated water tank with a concentrated water overflow port at the upper part through a concentrated water production pipe; the fresh water inlet pipe is connected to the fresh water chamber, and the fresh water chamber is connected to a second water tank through a fresh water production pipe; the electrode device includes a transformable cathode and anode, the cathode and anode are arranged on both sides of the membrane stack assembly, and one side of the cathode and anode adjacent to the membrane stack assembly respectively forms an electrode chamber with the membrane stack assembly; the electrode water outlet pipe and the electrode water inlet pipe are used to realize the circulating flow of the electrode water in the electrode chamber and the electrode water tank.

2. The anti-clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide according to claim 1, wherein, the first water tank is provided with a first side wall and a second side wall, and a slag discharge overflow weir and a water outlet overflow weir are respectively arranged at the upper parts of the first side wall and the second side wall. The first water tank is communicated with the second water tank through the water outlet overflow weir. The slag discharge overflow weir is arranged close to the slag discharge port, and a water inlet is arranged at the lower part of the first side wall and is connected to the inlet pipe.

3. The anti-clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide according to claim 1, wherein, the inlet water subsystem further includes an air inlet, and the air inlet is communicated with a micro-nano bubble generator; a turbidity on-line detector is arranged at the water outlet overflow weir; the micro-nano bubble generator is equipped with a pressure regulator; a pH on-line detector and a first conductivity on-line monitor are arranged at the fresh water overflow port; a baffle is arranged inside the second water tank for separating the drainage from the first water tank and the drainage from the fresh water production pipe; a water outlet flow regulating device is arranged on the outlet pipe.

4. The anti-clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide according to claim 1, wherein, a detachable filter bag and a differential pressure gauge are arranged inside the security filter, and the aperture of the filter holes of the detachable filter bag is 1-500 μm; a concentrated and fresh water flow distribution device is arranged between the detachable filter bag and the outlet end of the security filter.

5. The anti-clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide according to claim 1, wherein, the electrode device includes 3-15 pairs of electrode pairs of cathodes and anodes; the membrane stack assembly is arranged between the cathodes and anodes of each pair of electrode pairs and between adjacent electrode pairs. Each membrane stack assembly is provided with 3 - 20 cation exchange membranes, and the number of anion exchange membranes in each membrane stack assembly is one less than the number of cation exchange membranes in the same membrane stack assembly; On one side of the cathode adjacent to the membrane stack assembly, a cathode chamber is formed with the membrane stack assembly; On one side of the anode adjacent to the membrane stack assembly, an anode chamber is formed with the membrane stack assembly; The electrode device further includes a DC power supply; A second on - line conductivity monitor is provided in the cathode chamber.

6. The anti - clogging electrodialysis wastewater treatment system for resource utilization of carbon dioxide according to claim 1, wherein, A concentrated water return pipe is connected to the bottom of one side sidewall of the concentrated water tank. The concentrated water return pipe is used to send the concentrated water production of the concentrated water tank and the concentrated water inlet of the security filter into the concentrated water chamber together with the concentrated water inlet pipe; A regulating valve is provided on the concentrated water return pipe; A third on - line conductivity monitor is provided at the concentrated water overflow port.

7. A method for anti - clogging electrodialysis wastewater treatment for resource utilization of carbon dioxide, characterized in that, The method uses the system according to any one of claims 1 - 6, and includes the following steps: S1: Feed the high-salt industrial wastewater and the medicament into the first water tank through the water inlet pipe and the chemical dosing port respectively; Feed the mixed gas containing CO 2 into the first water tank and the second water tank in the form of bubbles through the micro-nano bubble generator; Above the first water tank, use the slag scraping device to discharge the scum, suspended impurities and foam in the first water tank out of the system through the slag discharge port, and the de-scum wastewater obtained enters the second water tank; S2: Send the slag - removed wastewater in the second water tank into the security filter through the water outlet pipe for filtration; obtain concentrated water inlet and fresh water inlet at the water outlet end of the security filter; send the concentrated water inlet and fresh water inlet into the concentrated water chamber and the fresh water chamber respectively for electrodialysis treatment; meanwhile, make the electrode water in the electrode water tank circulate between the electrode chamber and the electrode water tank by using the electrode water outlet pipe and the electrode water inlet pipe; S3: Obtain concentrated water production in the concentrated water chamber and send it into the concentrated water tank through the concentrated water production pipe, recover the high - salt wastewater through the concentrated water overflow port and further separate and recover the salt resources; obtain fresh water production in the fresh water chamber and send it into the second water tank through the fresh water production pipe, and recover the fresh water resources through the fresh water overflow port.

8. The method for anti - clogging electrodialysis wastewater treatment for resource utilization of carbon dioxide according to claim 7, wherein, In step S1: The water quality conditions of the high - salt industrial wastewater include: pH is 7 - 8.5, conductivity is 800 - 5000 μs / cm, total hardness is 50 - 400 mg / L, total alkalinity is 50 - 800 mg / L, TDS is 300 - 2500 mg / L, COD is 30 - 100 mg / L, TOC is 6 - 25 mg / L, and turbidity is 1.0 - 3.5 NTU; The medicament is at least one of a coagulant, a flocculant and a scale inhibitor. Preferably, the dosage ratio of the coagulant, the flocculant and the scale inhibitor is (1 - 10):(150 - 300):(0.1 - 1.5); The diameter of the bubbles is 1 μm - 80 μm, preferably 20 - 40 μm; The CO-containing 2 mixed gas is the gas obtained by the flue gas capture and separation process and / or the gas after the flue gas is purified by dust removal, desulfurization and denitrification. The temperature of the CO-containing 2 mixed gas is 40 to 120 °C, preferably 60 to 80 °C; The volume ratio range of the mixed gas containing CO 2 and the high-salt industrial wastewater is 5:1 to 25:1, preferably 15:1 to 20:1; The proportion range of the amount of the CO 2 -containing mixed gas fed into the first water tank and the second water tank through the micro-nano bubble generator is 1:1 to 1:10, preferably 1:4 to 1:6; Monitor the turbidity of the slag - removed wastewater by using the turbidity on - line detector, and control the turbidity of the slag - removed wastewater to be less than 0.6 NTU by adjusting at least one of the dosage of the medicament, the air intake of the air inlet, the pressure regulator and the output power of the slag scraping device; Use the on-line pH detector to monitor the pH of the effluent at the fresh water overflow outlet, and control the pH of the effluent at the fresh water overflow outlet to be less than 7 by adjusting the intake air volume of the air inlet and / or the proportion of CO 2 in the mixed gas containing CO 2 ; preferably, the proportion of CO 2 in the mixed gas containing CO 2 ranges from 10% to 80%, and more preferably from 20% to 40%.

9. The anti-clogging electrodialysis wastewater treatment method for resource utilization of carbon dioxide according to claim 8, wherein, the capture and separation process is at least one of pressure swing adsorption, molecular sieve adsorption, organic amine adsorption and membrane separation. Preferably, the capture and separation process is pressure swing adsorption.

10. The anti-clogging electrodialysis wastewater treatment method for resource utilization of carbon dioxide according to claim 7, wherein, in step S2: when the pressure difference in the security filter is ≥0.1 Mpa, replace the detachable filter bag in the security filter; the ratio of the fresh water inlet and the concentrated water inlet is 10:1 to 2:1, preferably 3:1 to 6:1; the method further includes swapping the cathode and the anode. Preferably, the interval time for swapping is determined according to the conductivity of the cathode chamber; the electrode water is an aqueous NaCl solution with a concentration of 0.5-3%; the ratio of the electrode water to the fresh water inlet is 1:(8-15).

11. The anti-clogging electrodialysis wastewater treatment method for resource utilization of carbon dioxide according to claim 7, wherein, in step S3: the method further includes taking part of the concentrated water produced in the concentrated water tank as the reflux concentrated water and sending it into the concentrated water chamber together with the concentrated water inlet; the amount of the reflux concentrated water is determined according to the conductivity of the water discharged from the concentrated water overflow port. Preferably, the ratio of the amount of the reflux concentrated water to the amount of the concentrated water inlet is 1:1 to 10:1, preferably 3:1 to 5:1.

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