Reclaimed water reuse treatment method and system

Abstract

The invention discloses a reclaimed water reuse treatment method and system, and relates to the technical field of wastewater treatment.The reclaimed water reuse treatment method comprises the steps that 1, reclaimed water is treated through an electrochemical softening procedure to obtain softened water, 2, the softened water is treated through a polarization oxidation procedure to obtain polarization oxidation water, and 3, the polarization oxidation water is subjected to reverse osmosis treatment, step 4, carrying out electrolytic adsorption treatment on the reverse osmosis concentrated water to obtain electrolyzed produced water to reuse the electrolyzed produced water to other water consumption units, and discharging the residual muddy concentrated water after electrolysis so as to reduce the amount of discharged water; and converging the electrolyzed water obtained in the step 4 and the polarized oxidized water generated after the step 2, and then carrying out reverse osmosis treatment in the step 3 and electrolytic adsorption treatment in the step 4. After the softened water is treated in the polarization oxidation process, scaling in the subsequent process can be avoided, and the problem that the reverse osmosis membrane is polluted and blocked during wastewater treatment in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and more particularly to a method and system for reusing reclaimed water. Background Art

[0002] Water sources such as domestic wastewater from urban office buildings, industrial production wastewater, boiler drainage, and biochemical reclaimed water are reclaimed water for seepage reuse with slightly higher ammonia nitrogen content and not too high COD content. If treated by a biochemical device, the treatment cost is too high, the device occupies a large area, the treatment process is long, and it is not easy to adopt. If treated by a coagulation sedimentation device, the treatment effect is poor, a large amount of chemical agents need to be added, and post-precipitation of the agents is likely to occur, which also increases the workload of the subsequent reverse osmosis membrane system. In addition, since a large number of microorganisms contained in the reclaimed water are not well sterilized, a bactericide needs to be added at the end of the softening process, and a flocculant needs to be added after the softening treatment. Therefore, an excessive amount of sodium bisulfite reducing agent needs to be added at the front end of ultrafiltration, which will promote the growth of sulfur-oxidizing bacteria, and the flocculant added at the front end is not suitable for the scale inhibition effect of the reverse osmosis scale inhibitor.

[0003] The patent with the publication number CN111499082A discloses a patent for an industrial wastewater treatment process based on electrolysis and membrane filtration, which specifically discloses the following steps: S1: performing a pretreatment process on the collected industrial wastewater; S2: performing an electrolytic oxidation process on the industrial wastewater, and filtering sludge through electrocoagulation;

[0004] S3: placing the filtered sludge in a sludge tank, and then performing sludge dewatering to obtain sludge; S4: filtering the industrial wastewater with the filtered sludge through an ultrafiltration membrane to obtain product water and concentrated liquid, wherein the concentrated liquid enters the sludge tank for subsequent dewatering process; S5: performing reverse osmosis treatment on the filtered product water to obtain concentrated liquid; S6: reusing or discharging the residual product water, which cannot solve the problem of fouling of the reverse osmosis membrane existing in the prior art during wastewater treatment. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. For this reason, the first aspect of the present invention provides a method for reusing reclaimed water, including:

[0006] Step 1, removing temporary hardness substances, permanent hardness substances, colloidal substances, and microorganisms in the reclaimed water by an electrochemical softening process to obtain softened water;

[0007] Step 2, using the charges generated by the polarization oxidation process to wrap the charged ions with opposite charges in the softened water to obtain polarization oxidation water;

[0008] Step 3, performing reverse osmosis treatment on the polarization oxidation water to remove the salt substances in the water to obtain reverse osmosis concentrated water and recyclable water;

[0009] Step 4: Electrolytic adsorption treatment is carried out on the reverse osmosis concentrated water to further remove salts in the reverse osmosis concentrated water, and electrolytic product water is obtained for reuse in other water-consuming units, and the remaining dilute sludge-like concentrated water after electrolysis is discharged externally;

[0010] Step 5: The electrolytic product water obtained after performing Step 4 is fed back to Step 2 and merged with the polarized oxidized water generated after performing Step 2, and then the reverse osmosis treatment in Step 3 and the electrolytic adsorption treatment in Step 4 are carried out in sequence.

[0011] Optionally, in the electrochemical softening process, the electrochemical reaction is carried out until the pH value of the cathode is greater than 13.

[0012] Optionally, the high-voltage static voltage used in the polarization oxidation process is 26000V.

[0013] Optionally, when carrying out the electrolytic adsorption treatment, electrocoagulation treatment of the reverse osmosis concentrated water is also included.

[0014] Optionally, after the electrolytic product water obtained after performing Step 4 is fed back to Step 2 and merged with the polarized oxidized water generated after performing Step 2, it further includes:

[0015] The merged polarized oxidized water and electrolytic product water are sequentially subjected to sand filtration and ultrafiltration treatment to remove suspended solids and macromolecules in the depolarized oxidized water and electrolytic product water, and filtered water is obtained;

[0016] After the filtered water is obtained, the filtered water is sequentially subjected to reverse osmosis treatment and electrolytic adsorption treatment;

[0017] The electrolytic product water after the electrolytic adsorption treatment is merged with the polarized oxidized water again, and then sequentially subjected to sand filtration, ultrafiltration treatment, reverse osmosis treatment and electrolytic adsorption treatment. Recyclable water is obtained after the reverse osmosis treatment, and electrolytic product water is obtained after the electrolytic adsorption treatment for reuse in other water-consuming units, and the remaining dilute sludge-like concentrated water after electrolysis is discharged externally.

[0018] On the other hand, the present invention also provides a reclaimed water reuse treatment system, including:

[0019] An electrochemical softening device, which is used to remove temporary hardness substances, permanent hardness substances, colloidal substances and microorganisms in the reclaimed water to obtain softened water;

[0020] A polarization oxidation device, which is used to wrap charged ions with opposite charges in the softened water by the charges generated in the polarization oxidation process to obtain polarized oxidized water;

[0021] A reverse osmosis membrane device, which is used to perform reverse osmosis treatment on the polarized oxidized water to remove salt substances in the water and obtain reverse osmosis concentrated water and recyclable water;

[0022] An electrolytic adsorption device is used to perform electrolytic adsorption treatment on reverse osmosis concentrated water to further remove salts in the reverse osmosis concentrated water, obtain electrolytic product water for reuse in other water-consuming units, discharge the remaining dilute sludge-like concentrated water electrolytically, merge the obtained electrolytic product water and polarized oxidation water and then input them into a reverse osmosis membrane device for treatment, and partially discharge the remaining dilute sludge-like concentrated water electrolytically.

[0023] Optionally, before the reverse osmosis membrane device, there is also a sand filtration device and an ultrafiltration device, which are used to perform sand filtration on the merged polarized oxidation water and electrolytic product water and then perform ultrafiltration treatment to remove suspended solids and macromolecules in the merged polarized oxidation water and electrolytic product water, obtaining filtered water;

[0024] After obtaining the filtered water, use the reverse osmosis membrane device to perform reverse osmosis treatment on the filtered water to obtain reverse osmosis concentrated water and recyclable water, and then use the electrolytic adsorption device to treat the reverse osmosis concentrated water to obtain electrolytic product water and the remaining dilute sludge-like concentrated water electrolytically;

[0025] After merging the obtained electrolytic product water and polarized oxidation water, perform cyclic treatment successively using the sand filtration device, ultrafiltration device, reverse osmosis membrane device, and electrolytic adsorption device.

[0026] Optionally, the reverse osmosis membrane device is a disk-type reverse osmosis membrane.

[0027] Optionally, the ultrafiltration device is a honeycomb ceramic ultrafiltration membrane.

[0028] The embodiment of the present invention provides a method and system for reusing reclaimed water. Compared with the prior art, its beneficial effects are as follows:

[0029] The method and system provided by the present invention directly enter the reclaimed water into electrochemical softening treatment to remove part of the temporary hardness, permanent hardness, colloid, and organic matter, and kill part of the microorganisms, then perform polarized oxidation treatment, use charged water molecules to continuously wrap ions with opposite charges to remove conductive ions, then perform reverse osmosis for desalination treatment, and then perform electrolytic adsorption treatment. After the result of the electrolytic adsorption treatment is fed back, reverse osmosis treatment is performed. After the softened water is treated in the polarized oxidation process of the present invention, scale formation can be avoided in subsequent processes, and the problem of fouling of the reverse osmosis membrane during wastewater treatment in the prior art can be solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the present invention, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0031] Figure 1 Schematic flow chart of the first embodiment of a reclaimed water treatment method provided by an embodiment of the present invention;

[0032] Figure 2 Schematic flow chart of the second embodiment of a reclaimed water treatment method provided by an embodiment of the present invention;

[0033] Figure 3 Schematic structural diagram of the first embodiment of a reclaimed water treatment system provided by an embodiment of the present invention;

[0034] Figure 4 Schematic structural diagram of the second embodiment of a reclaimed water treatment system provided by an embodiment of the present invention. Detailed implementation manners

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] This specification provides method operation steps as described in the embodiments or flowcharts, but may include more or fewer operation steps based on routine or non-creative labor. When actually executed by a system or server product, it may be executed sequentially or in parallel according to the methods shown in the embodiments or the drawings (for example, in an environment of parallel processors or multi-threaded processing).

[0037] Please refer to Figure 1 , Figure 1 Schematic flow chart of the first embodiment of a reclaimed water treatment method provided by an embodiment of the present invention. The reclaimed water treatment method provided in the first embodiment of the present invention is used to solve the problem of fouling of the reverse osmosis membrane during the reclaimed water treatment process existing in the prior art, as Figure 1 shown, the method of the first embodiment includes:

[0038] Step 1, removing temporary hardness substances, permanent hardness substances, colloid substances and microorganisms in the reclaimed water by an electrochemical softening process to obtain softened water.

[0039] Among them, the principle of the electrochemical softening method is to adsorb charged particles in water on the surface of charged electrodes, so that dissolved salts, charged particles, etc. in the water are enriched on the electrode surface, and the dissolved salts, colloids, and charged substances in the wastewater to be treated are continuously reduced, thereby achieving the purpose of hardness removal. Among them, permanent hardness, also known as non-carbonate hardness, is mainly the hardness formed by calcium and magnesium bicarbonates, and there is also a small amount of carbonate hardness. Temporary hardness, also known as carbonate hardness, is a part of the total water hardness, that is, the hardness formed by calcium and magnesium ions combined with bicarbonate (hydrogen carbonate) and a small amount of carbonate ions in water. Substances with permanent hardness include CaSO4, MgSO4, CaCl2, MgCl2, Ca(NO3)2, Mg(NO3)2, etc. Substances with temporary hardness include: Ca(HCO3), CaCO3, Mg(HCO3)2, Mg(OH)2, etc. The electrochemical softening method also has a killing effect on microorganisms and can reduce the organic matter content to a certain extent. Through the electrochemical softening method, no chemical agents including sulfuric acid and corrosion and scale inhibitors need to be added, thereby reducing the problem of fouling of the reverse osmosis membrane that exists in the prior art during the reclaimed water treatment process. This is the improvement of the present invention over the prior art.

[0040] Exemplarily, in the electrochemical softening process, the pH value of the reaction at the cathode is above 13 to accelerate the removal of temporary hardness substances, permanent hardness substances, colloid substances, and microorganisms in the reclaimed water.

[0041] Exemplarily, after using the electrochemical softening process to remove temporary hardness substances, permanent hardness substances, colloid substances, and microorganisms in the reclaimed water, the removal rate of single-stage temporary hardness substances in the reclaimed water is 30% - 50%, and the removal rate of single-stage permanent hardness substances is more than 45%. Among them, single-stage refers to one electrochemical softening process. After performing a single-stage electrochemical softening process, the removal rate of single-stage temporary hardness substances in the reclaimed water of the present invention is 30% - 50%, and the removal rate of single-stage permanent hardness substances is more than 45%, thereby not adding any chemical agents including sulfuric acid and corrosion and scale inhibitors, and further reducing the dosage of the agents.

[0042] Step 2: Use the charges generated by the polarization oxidation process to wrap the charged ions with opposite charges in the softened water to obtain polarization oxidation water.

[0043] Among them, the polarization oxidation process is to use the charges generated by the polarization oxidation process to wrap the charged ions with opposite charges in the softened water. After the present invention treats the softened water in the polarization oxidation process, scaling in the subsequent reverse osmosis process can be avoided, and the problem of fouling of the reverse osmosis membrane that exists in the prior art during wastewater treatment can be solved.

[0044] Exemplarily, the high-voltage static electricity voltage used in the polarization oxidation process is 26000V, and the duration of the polarization oxidation process is more than 40 minutes. By using the polarization oxidation process, high-voltage static electricity of 26000V can be generated to scale inhibition treat reverse osmosis. With an effective electrode polarization time of more than 40 minutes, the dosage of reverse osmosis chemicals can be reduced, the water production of reverse osmosis can be increased, and the desalination rate of reverse osmosis can be effectively guaranteed.

[0045] Step 3: Perform reverse osmosis treatment on the polarization oxidized water to remove the salts in the water, obtaining reverse osmosis concentrated water and recyclable water.

[0046] Among them, RO reverse osmosis treatment of wastewater is also a commonly used step in wastewater treatment, and its purpose is to remove the salts in the polarization oxidized water. After RO reverse osmosis treatment of the polarization oxidized water, recyclable water is produced for use, and the remaining reverse osmosis concentrated water is used for subsequent treatment.

[0047] Step 4: Perform electro-adsorption treatment on the reverse osmosis concentrated water to further remove the salts in the reverse osmosis concentrated water, obtaining reverse osmosis concentrated water and recyclable water.

[0048] Among them, after treating the reverse osmosis concentrated water by the electro-adsorption process, the salts in the reverse osmosis concentrated water are further treated to obtain electrolytic produced water for reuse in other water-consuming units, and the remaining dilute mud-like concentrated water after electrolysis is discharged.

[0049] Step 5: Feed the electrolytic produced water obtained after performing Step 4 back to after Step 2, mix it with the polarization oxidized water produced after performing Step 2, and then successively perform the reverse osmosis treatment in Step 3 and the electro-adsorption treatment in Step 4.

[0050] After the electrolytic produced water is mixed with the polarization oxidized water, reverse osmosis treatment is directly carried out. After reverse osmosis treatment, recyclable water and reverse osmosis concentrated water are produced. Then, the electro-adsorption process is used to treat the reverse osmosis concentrated water, so as to obtain electrolytic produced water for reuse in other water-consuming units, and the remaining dilute mud-like concentrated water after electrolysis is discharged, completing one cycle. This is also an improvement of the present invention over the prior art. After electro-adsorption treatment, the water recovery rate is above 90%, the desalinated concentrated water can be effectively reduced, and some salts are precipitated in the form of salt slag, realizing the functions of softening water quality and desalination concentration.

[0051] Exemplarily, when performing electro-adsorption treatment, it also includes electrocoagulation treatment of the reverse osmosis concentrated water.

[0052] Exemplarily, after electrolysis, electrocoagulation and electro-adsorption of the reverse osmosis concentrated water, the single-stage chloride ion removal rate in the reverse osmosis concentrated water is above 70%, and the single-stage desalination rate is above 75%. Among them, single-stage refers to a single electro-adsorption device.

[0053] In summary, in the embodiment of the present invention, reclaimed water directly enters the electrochemical softening treatment to remove part of the temporary hardness, permanent hardness, colloid and organic matter, and kill part of the microorganisms, and then undergoes polarization oxidation treatment. The charged water molecules continuously wrap the ions with opposite charges, and then reverse osmosis is carried out for desalination treatment, and then electrolytic adsorption treatment is carried out. After the result of the electrolytic adsorption treatment is fed back, reverse osmosis treatment is carried out, which can solve the problem of fouling of the reverse osmosis membrane existing in the prior art during the reclaimed water treatment process. The present invention avoids the problems of high treatment cost, large floor area occupied by the device, and long treatment process flow in the biochemical device treatment, and also avoids the problems of poor treatment effect in the coagulation sedimentation device treatment, the need to add a large amount of chemical agents, and the easy occurrence of post-precipitation of the agents, which will increase the workload of the subsequent reverse osmosis membrane system. The present invention discharges the remaining dilute mud-like concentrated water after electrolysis, and the concentration degree is high, which can reduce the external discharge amount.

[0054] Please refer to Figure 2 , Figure 2 which is a schematic flow chart of the second embodiment of a reclaimed water reuse treatment method provided by the embodiment of the present invention. As Figure 2 shown, the implementation steps of the method provided in the second embodiment include:

[0055] Step 1, using the electrochemical softening process to remove the temporary hardness substances, permanent hardness substances, colloid substances and microorganisms in the reclaimed water to obtain softened water.

[0056] For the specific description of Step 1, please refer to Figure 1 Step 101 of the reclaimed water reuse treatment method described.

[0057] Step 2, using the charges generated by the polarization oxidation process to wrap the charged ions with opposite charges in the softened water to obtain polarization oxidation water.

[0058] For the specific description of Step 2, please refer to Figure 1 Step 102 of the reclaimed water reuse treatment method described.

[0059] Step 3, performing sand filtration on the polarization oxidation water and then performing ultrafiltration treatment to remove the suspended substances and macromolecular substances in the polarization oxidation water to obtain filtered water.

[0060] Among them, the fluidized sand filter is an effective solution for water treatment and sewage purification to remove solid suspended matters and other turbidity. It can effectively remove impurities such as suspended particulate matters and colloids in softened water. The filter media of the fluidized sand filter uses granular filter media as the filling layer, and the circulating water continuously impacts the filling layer from below, making the granular filter media in a floating state, thus playing a role in biological filtration and nitrification. The fluidized sand filter is a biological filter and has no physical filtration function. All organic impurities must be decomposed by the biofilm formed on the surface of microbial solids. Therefore, its filter media has the dual functions of eliminating organic impurities and nitrification. After fluidized sand filtration, ultrafiltration treatment is carried out. Ultrafiltration is a pressure membrane separation technology, that is, under a certain pressure, small molecule solutes and solvents pass through a special thin film with a certain pore size, while macromolecule solutes cannot pass through and remain on one side of the membrane, so that the macromolecule substances are partially purified, and thus the filtered water after the macromolecule water is blocked is obtained.

[0061] In step 3, which is an additional step based on Example 1, fluidized sand filtration and ultrafiltration treatment are added before reverse osmosis treatment. The fluidized sand filtration is used to remove suspended matters and turbidity in the polarized oxidized water, and the ultrafiltration treatment is used to remove macromolecular salts in the softened water with suspended matters and turbidity, obtaining filtered water. After the treatment in step 2, the conductivity of the water body is reduced, and the water production and water quality of ultrafiltration and reverse osmosis are improved.

[0062] Step 4: Perform reverse osmosis treatment on the filtered water to obtain reverse osmosis concentrated water and recyclable water.

[0063] Step 5: Perform electro-adsorption treatment on the reverse osmosis concentrated water to further remove salts in the reverse osmosis concentrated water. The electro-produced water obtained is merged with the polarized oxidized water, and then the fluidized sand filter device, ultrafiltration device, reverse osmosis membrane device, and electro-adsorption device are used for cyclic treatment in sequence.

[0064] Among them, after obtaining the filtered water, it also includes performing reverse osmosis treatment on the filtered water to obtain reverse osmosis concentrated water and recycled water, and then performing electro-adsorption treatment on the reverse osmosis concentrated water to obtain electro-produced water and the remaining dilute mud-like concentrated water after electrolysis. After performing reverse osmosis treatment on the obtained filtered water, further desalination is carried out to obtain reverse osmosis concentrated water and recyclable water, and the recyclable water is used for recycling. Then, electro-adsorption treatment is performed on the reverse osmosis concentrated water. Electro-adsorption has the functions of electrolysis, electrocoagulation, and electro-adsorption, further removing salts and chloride ions. The remaining dilute mud-like concentrated water after electrolysis is discharged, greatly reducing the discharge volume.

[0065] In the embodiment of the present invention, reclaimed water directly enters electrochemical softening treatment to remove part of the temporary hardness, permanent hardness, colloid and organic matter, and kill part of the microorganisms, and then undergoes polarization oxidation treatment. The charged water molecules continuously wrap the ions with opposite charges, and then through ultrafiltration and sand filtration, suspended solids, turbidity and macromolecular salts are further removed. Then, conventional ultrafiltration and RO reverse osmosis membrane are used for desalination treatment, and then through electrolytic adsorption treatment, and then fed back to before the ultrafiltration step, the problem of fouling of the reverse osmosis membrane existing in the prior art during the reclaimed water treatment process can be solved.

[0066] Reference Figure 3 , Figure 3 FIG. 300 is a schematic structural diagram of a first embodiment of a reclaimed water reuse treatment system provided by an embodiment of the present invention. The system 300 provided in this embodiment includes:

[0067] An electrochemical softening device 301, which is used to remove temporary hardness substances, permanent hardness substances, colloid substances and microorganisms in reclaimed water to obtain softened water.

[0068] The model of the electrochemical softening device 301 is SYDD-1011. There are a first water inlet tank and a first water outlet tank at its front end and rear end respectively, and water pumps are provided in both the first water inlet tank and the first water outlet tank.

[0069] A polarization oxidation device 302, which is used to wrap the charged ions with opposite charges in the softened water by using the charges generated by the polarization oxidation process to obtain polarization oxidation water.

[0070] The model of the polarization oxidation device 302 is SYDY1015. Its water inlet end is the first water outlet tank, and its water outlet end is the second water outlet tank.

[0071] A reverse osmosis membrane device 303, which is used to perform reverse osmosis treatment on the polarization oxidation water to remove salt substances in the water to obtain reverse osmosis concentrated water and recyclable water.

[0072] The reverse osmosis membrane device 303 uses a disc type reverse osmosis membrane, which has the characteristics of high osmotic pressure, less scaling, low later maintenance cost and long service life. Among them, the disc type reverse osmosis membrane uses a medium pressure membrane, and its pore size range is 5000-10000 nanometers. The input of the reverse osmosis membrane device 303 is the water pressed from the second water outlet tank, and the output is to the third water outlet tank.

[0073] An electrolytic adsorption device 304, which is used to perform electrolytic adsorption treatment on the reverse osmosis concentrated water to further remove salts in the reverse osmosis concentrated water to obtain electrolytic product water for reuse in other water-consuming units, discharge the remaining dilute sludge-like concentrated water, merge the obtained electrolytic product water and the polarization oxidation water and input them into the reverse osmosis membrane device for treatment, and discharge part of the remaining dilute sludge-like concentrated water.

[0074] The model of the electro-adsorption device 304 is SYDJ2011. After the water in the third effluent tank is pumped out by a water pump, it is treated by the electro-adsorption device 304 and then output to the fourth effluent tank. The water output from the fourth effluent tank is pumped into the second effluent tank.

[0075] It should be noted that the present invention does not separately improve the electro-chemical softening device 301, the polarization oxidation device 302, the reverse osmosis membrane device 303, and the electro-adsorption device 304, and the ones adopted are all existing technologies. The improvement of the present invention lies in the improvement of the intermediate water treatment process, that is, an electro-chemical softening device 301 and a polarization oxidation device 302 are added before the reverse osmosis membrane device 303, and an electro-adsorption device 304 is added after the reverse osmosis membrane device 303. After the reverse osmosis concentrated water generated by the reverse osmosis membrane device 303 is treated by the electro-adsorption device 304, the electro-produced water obtained is fed back to the reverse osmosis membrane device 303 for treatment, and the remaining dilute sludge-like concentrated water after electrolysis is discharged. The wastewater obtained after the treatment of the reverse osmosis membrane device 303 is recycled, and the reverse osmosis concentrated water continues to be treated by electro-adsorption, so as to achieve the cyclic treatment of wastewater and reduce the external discharge rate of wastewater.

[0076] The present invention does not require the addition of a large amount of chemical agents and will not increase the workload of the reverse osmosis membrane at the back end. No bactericide and flocculant are added at the end of softening, so it will not increase the workload of the reverse osmosis membrane at the back end either.

[0077] In summary, in the embodiment of the present invention, the intermediate water directly enters the electro-chemical softening device 301 to remove part of the temporary hardness, permanent hardness, colloid and organic matter, and kill part of the microorganisms to obtain softened water. Then the softened water is sent to the polarization oxidation device 302, and the charged water molecules are used to continuously wrap the ions with opposite charges to obtain polarization oxidized water. Then, the conventional reverse osmosis membrane device 303 is used for desalination treatment, and then through the electro-adsorption device 304, salts and chloride ions are further removed, reducing the external discharge rate of wastewater. The embodiment provided by the present invention can solve the problem of fouling of the reverse osmosis membrane existing in the prior art during the intermediate water treatment process.

[0078] Reference Figure 4 , Figure 4 FIG. is a schematic structural diagram of a second embodiment of a system for treating and reusing intermediate water provided by an embodiment of the present invention. The system 300 provided by this embodiment further includes:

[0079] Before the reverse osmosis membrane device 303, there is also a sand filtration device 305 and an ultrafiltration device 306, which are used for sand filtration of the polarization oxidized water and the electro-produced water output from the electro-adsorption device and then for ultrafiltration treatment to remove the suspended substances and macromolecular substances in the polarization oxidized water to obtain filtered water.

[0080] It should be noted that the quicksand filtration device 305 and the ultrafiltration device 306 are both prior arts, and no improvements are made to the devices used. The difference between this embodiment and the previous embodiment lies in that after ultrafiltration and quicksand filtration, the suspended solids, turbidity, and macromolecular salts are further reduced to prevent fouling of the reverse osmosis membrane.

[0081] In the embodiment of the present invention, the electrolytic water produced by the polarization oxidation water and the electrolytic adsorption device 304 is subjected to quicksand filtration and then ultrafiltration treatment to obtain filtered water. Then, the reverse osmosis membrane device 303 performs reverse osmosis treatment on the filtered water to obtain reverse osmosis concentrated water and recycled water. Then, the electrolytic adsorption device 304 is used to treat the reverse osmosis concentrated water to obtain electrolytic water and electrolytic residual concentrated water. This embodiment is a subsequent different treatment method after adding the quicksand filtration device 305 and the ultrafiltration device 306 on the basis of the previous embodiment. After adding the quicksand filtration device 305 and the ultrafiltration device 306, the degree of fouling of the reverse osmosis membrane can be greatly alleviated.

[0082] The ultrafiltration device 306 in the embodiment of the present invention is a honeycomb ceramic membrane. The honeycomb ceramic membrane has high acid and alkali resistance, high anti-pollution degree, and can be cleaned by combining two methods of hydraulic backwashing and air pressure backwashing, which can effectively improve the anti-pollution degree of the membrane and increase the water production flux.

[0083] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the presence of additional identical elements in the process, method, article or device including the element.

[0084] Each embodiment in this specification is described in a related manner. The same or similar parts between each embodiment can be referred to each other, and the differences between each embodiment and other embodiments are emphasized. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment.

[0085] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A method for treating reclaimed intermediate water, characterized in that, including: Step 1: Use an electrochemical softening process to remove temporary hardness substances, permanent hardness substances, colloidal substances, and microorganisms in the reclaimed water to obtain softened water; Step 2: Use the charges generated in the polarization oxidation process to wrap the charged ions with opposite charges in the softened water to obtain polarization oxidation water; Step 3: Perform reverse osmosis treatment on the polarization oxidation water to remove the salt substances in the water to obtain reverse osmosis concentrated water and recyclable water; Step 4: Perform electro-adsorption treatment on the reverse osmosis concentrated water to further remove the salt in the reverse osmosis concentrated water to obtain electro-generated water for reuse in other water-consuming units, and discharge the remaining dilute sludge-like concentrated water after electrolysis; Step 5: After performing Step 4, feedback the electro-generated water obtained to after Step 2, merge it with the polarization oxidation water generated after performing Step 2, and then sequentially perform the reverse osmosis treatment in Step 3 and the electro-adsorption treatment in Step 4.

2. The reclaimed water reuse treatment method according to claim 1, wherein In the electrochemical softening process, the electrochemical reaction is carried out until the pH value of the cathode is greater than 13.

3. The reclaimed water reuse treatment method according to claim 1, characterized in that, The high-voltage static voltage used in the polarization oxidation process is 26000V.

4. The reclaimed water reuse treatment method according to claim 1, wherein, When performing the electro-adsorption treatment, electrocoagulation treatment of the reverse osmosis concentrated water is also included.

5. The method for treating reclaimed intermediate water according to claim 1, wherein After the electro-generated water obtained after performing Step 4 is feedback to after Step 2 and merged with the polarization oxidation water generated after performing Step 2, it also includes: Perform sand filtration and ultrafiltration treatment on the merged polarization oxidation water and electro-generated water in sequence to remove suspended solids and macromolecules in the polarization oxidation water and electro-generated water to obtain filtered water; After obtaining the filtered water, perform reverse osmosis treatment and electro-adsorption treatment on the filtered water in sequence; Merge the electro-generated water after electro-adsorption treatment with the polarization oxidation water again, and then sequentially perform sand filtration, ultrafiltration treatment, reverse osmosis treatment, and electro-adsorption treatment. Recyclable water is obtained after reverse osmosis treatment, and electro-generated water is obtained after electro-adsorption treatment for reuse in other water-consuming units, and the remaining dilute sludge-like concentrated water after electrolysis is discharged.

6. A reclaimed water reuse treatment system, characterized in that, including: An electrochemical softening device, which is used to remove temporary hardness substances, permanent hardness substances, colloidal substances, and microorganisms in the reclaimed water to obtain softened water; A polarization oxidation device, which is used to use the charges generated in the polarization oxidation process to wrap the charged ions with opposite charges in the softened water to obtain polarization oxidation water; A reverse osmosis membrane device, which is used to perform reverse osmosis treatment on the polarization oxidation water to remove the salt substances in the water to obtain reverse osmosis concentrated water and recyclable water; An electro-adsorption device, which is used to perform electro-adsorption treatment on the reverse osmosis concentrated water to further remove the salt in the reverse osmosis concentrated water to obtain electro-generated water for reuse in other water-consuming units, discharge the remaining dilute sludge-like concentrated water after electrolysis, input the obtained electro-generated water and polarization oxidation water after merging into the reverse osmosis membrane device for treatment, and discharge part of the remaining dilute sludge-like concentrated water after electrolysis.

7. The reclaimed water reuse treatment system according to claim 6, characterized in that, Before the reverse osmosis membrane device, there is also a sand filtration device and an ultrafiltration device, which are used to perform sand filtration on the merged polarization oxidation water and electro-generated water and then perform ultrafiltration treatment to remove suspended solids and macromolecules in the merged polarization oxidation water and electro-generated water to obtain filtered water; After obtaining the filtered water, the reverse osmosis membrane device is used to perform reverse osmosis treatment on the filtered water to obtain reverse osmosis concentrated water and recyclable water, and then the electrolytic adsorption device is used to treat the reverse osmosis concentrated water to obtain electrolytic product water and dilute sludge-like concentrated water remaining after electrolysis; After the obtained electrolytic product water is merged with the polarized oxidation water, it is then cyclically treated by using a sand filtration device, an ultrafiltration device, a reverse osmosis membrane device, and an electrolytic adsorption device in sequence.

8. The reclaimed water reuse treatment system according to claim 6, characterized in that, The reverse osmosis membrane device is a disc-type reverse osmosis membrane.

9. A reclaimed water reuse treatment system according to claim 7, wherein The ultrafiltration device is a honeycomb ceramic ultrafiltration membrane.

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