Softening system and method for removing scaling ions from high-scale inhibitor concentrated water

Abstract

The invention relates to the technical field of water treatment, and discloses a softening system and method for removing scaling ions from high scale inhibitor concentrated water, the system comprises a dosing softening clarification unit group, a filter and an ion exchange hardness removal device; the input end of the dosing, softening and clarifying unit group is used for inputting concentrated water with high salinity and high scale inhibitor content; the output end of the dosing, softening and clarifying unit group is connected with the input end of the filter; and the output end of the filter is connected with the input end of the ion exchange hardness removal device. Through sequential treatment of the dosing softening and clarifying unit group, the filter and the ion exchange hardness removal device, scaling ions in the concentrated water with high salinity and high scale inhibitor content are effectively removed, hardness components in the water are remarkably reduced, the possibility that the scaling ions are deposited on the surface of a heat exchange tube to form a scale layer in the concentration, evaporation and crystallization process is reduced, and the service life of the concentrated water is prolonged. Therefore, the scaling phenomenon of the heat exchange tube is avoided, and the normal heat transfer performance of the heat exchange tube is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and specifically to a softening system and method for removing scaling ions from high-scale inhibitor concentrated water. Background Art

[0002] At present, zero liquid discharge of high-salt concentrated water is an important way to realize water resource utilization and environmental protection, especially for reverse osmosis concentrated water. Among them, the thermal concentration-evaporation crystallization technical solution is a current mainstream route. However, there are many problems in the thermal concentration process of high-salt concentrated water: one is the problem of fouling on heat transfer surfaces such as silica scale and hard scale frequently occurring in thermal concentration devices, especially when the influent water quality is unstable and the water volume fluctuates greatly, and there is a lack of effective pretreatment means; the other is that traditional silicon and hardness removal technologies have not been widely studied in high-salt concentrated water with high chlorine, high sodium, low calcium and magnesium, and high scale inhibitor content. Especially after the concentrated water is concentrated by a reverse osmosis membrane multiple times, the scale inhibitor content in the water is extremely high. The presence of the scale inhibitor seriously affects the hardness removal ability of the concentrated water, resulting in the reaction and formation of hardness ions in the subsequent thermal concentration and evaporation crystallization systems, and situations such as fouling and blockage occur. How to efficiently and reliably solve the influence of high-concentration scale inhibitors in concentrated water on hardness removal and how to effectively remove scaling ions in concentrated water are the key links affecting zero liquid discharge of concentrated water. Summary of the Invention

[0003] In order to overcome the defects existing in the above-mentioned prior art, the purpose of the present invention is to provide a softening system and method for removing scaling ions from high-scale inhibitor concentrated water, so as to solve the technical problems of easy fouling, blockage and inefficiency of heat exchange tubes that are extremely likely to occur in the evaporation crystallization process in the prior art.

[0004] The present invention is realized through the following technical solutions: In the first aspect, the present invention provides a softening system for removing scaling ions from high-scale inhibitor concentrated water, including a chemical dosing softening clarification unit group, a filter, and an ion exchange hardness removal device; The input end of the chemical dosing softening clarification unit group is used to input concentrated water with high salinity and high scale inhibitor content; the output end of the chemical dosing softening clarification unit group is connected to the input end of the filter; The output end of the filter is connected to the input end of the ion exchange hardness removal device.

[0005] Preferably, the chemical dosing softening clarification unit group includes a primary chemical dosing softening clarification unit and a secondary chemical dosing softening clarification unit; The input end of the primary chemical dosing softening clarification unit is used to input concentrated water with high salinity and high scale inhibitor content; The output end of the primary chemical dosing softening clarification unit is connected to the input end of the secondary chemical dosing softening clarification unit; The output end of the secondary chemical dosing softening clarification unit is connected to the filter.

[0006] Further, the primary chemical addition softening clarification unit includes a silicon removal reaction clarifier and a first chemical addition unit group; The first chemical addition unit group includes a silicon removal agent chemical addition unit, a first scavenger chemical addition unit, a first flocculant chemical addition unit, and a first coagulant aid chemical addition unit; The input end of the silicon removal reaction clarifier is used to input concentrated water with high salinity and high scale inhibitor content; The output end of the silicon removal reaction clarifier is connected to the input end of the secondary chemical addition softening clarification unit; The silicon removal agent chemical addition unit, the first scavenger chemical addition unit, the first flocculant chemical addition unit, and the first coagulant aid chemical addition unit are all connected to the chemical addition end of the silicon removal reaction clarifier.

[0007] Furthermore, the secondary chemical addition softening clarification unit includes a hardness removal reaction clarifier and a second chemical addition unit group; The second chemical addition unit group includes an alkalizing agent chemical addition unit, a softening agent chemical addition unit, a second flocculant chemical addition unit, a second coagulant aid chemical addition unit, a second scavenger chemical addition unit, and an acidifying agent chemical addition device; The input end of the hardness removal reaction clarifier is connected to the output end of the silicon removal reaction clarifier; The output end of the hardness removal reaction clarifier is connected to the filter; The alkalizing agent chemical addition unit, the softening agent chemical addition unit, the second flocculant chemical addition unit, the second coagulant aid chemical addition unit, and the second scavenger chemical addition unit are all connected to the chemical addition end of the hardness removal reaction clarifier; The acidifying agent chemical addition device is arranged between the hardness removal reaction clarifier and the filter.

[0008] Furthermore, the hardness removal reaction clarifier is further connected with an aeration unit for arranging external air inside the hardness removal reaction clarifier.

[0009] Preferably, the filter is filled with multi-media filtration media for filtering and removing turbidity from the liquid.

[0010] Preferably, the ion exchange hardness removal device is filled with chelating resin for hardness removal to achieve ultimate removal of calcium ions and magnesium ions in the liquid through ion exchange.

[0011] Second, the present invention also provides a method for using a softening system for removing scaling-causing ions from high scale inhibitor concentrated water. Based on the above-mentioned softening system for removing scaling-causing ions from high scale inhibitor concentrated water, it includes: Input the concentrated water with high salinity and high scale inhibitor content into the chemical addition softening clarification unit group for clarification, and then input it into the filter for filtering and removing turbidity; The liquid after filtration and turbidity removal enters the ion exchange hard removal device, and the calcium ions and magnesium ions in the liquid are removed to the limit through ion exchange, completing the work of removing scaling-causing ions from the high-scale inhibitor concentrated water.

[0012] Preferably, the chemical dosing softening clarification unit group includes a primary chemical dosing softening clarification unit and a secondary chemical dosing softening clarification unit, and the hydraulic retention time of the primary chemical dosing softening clarification unit and the secondary chemical dosing softening clarification unit is not less than 30 min.

[0013] Preferably, the ion exchange hard removal device is filled with chelating resin for hard removal. The chelating resin for hard removal is a macroporous styrene resin, and the group of the macroporous styrene resin is an iminodiacetic acid group. The chelating resin for hard removal forms a chelate with metal ions in the liquid and realizes removal through the chelate. When the chelating resin for hard removal is saturated by adsorption, its ion exchange performance can be restored through external acid-base regeneration.

[0014] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention provides a softening system for removing scaling-causing ions from high-scale inhibitor concentrated water. Through the sequential treatment of the chemical dosing softening clarification unit group, the filter, and the ion exchange hard removal device, the scaling-causing ions in the concentrated water with high salinity and high scale inhibitor content are effectively removed, the hardness components in the water are significantly reduced, and the possibility of the scaling-causing ions depositing on the surface of the heat exchange tubes to form a scale layer during the concentration evaporation crystallization process is reduced, thereby avoiding the occurrence of heat exchange tube scaling and ensuring the normal heat transfer performance of the heat exchange tubes. It effectively realizes the fractional precipitation removal and ultimate removal of main scaling-causing ions such as calcium ions, magnesium ions, and silicate ions, and effectively ensures the reliable and stable operation of subsequent thermal concentration-evaporation crystallization.

[0015] Furthermore, through the fractional treatment of the primary chemical dosing softening clarification unit and the secondary chemical dosing softening clarification unit, more refined removal of scaling-causing ions can be carried out for the concentrated water with high salinity and high scale inhibitor content. The primary chemical dosing softening clarification unit can initially remove most of the suspended solids and part of the scaling-causing ions, and the secondary chemical dosing softening clarification unit further removes the remaining scaling-causing ions and fine particles, ensuring that the water quality entering the subsequent treatment unit is purer.

[0016] Even further, through the synergistic effect of the silicon removal reaction clarifier and the first chemical dosing unit group in the primary chemical dosing softening clarification unit, by adding a scale inhibitor eliminator, the ability of the microcrystals of scale samples such as calcium aluminosilicate to combine and grow is improved, realizing functions such as efficient silicon removal, microcrystal combination, and enhanced flocculation precipitation, and providing high-quality water quality conditions for the subsequent treatment unit.

[0017] Furthermore, through the synergistic effect of the hardness removal reaction clarifier and the second chemical dosing unit group in the secondary chemical dosing softening and clarification unit, by adding scale inhibitor eliminator, the surface activity of metal cations is effectively activated, the binding and growth ability of microcrystals of scale samples such as calcium carbonate is improved, and functions such as efficient hardness removal, pH value adjustment, enhanced flocculation precipitation, and overcoming the inhibition ability of high-concentration scale inhibitor are realized, providing high-quality water quality conditions for the subsequent filtration and ion exchange treatment units, improving the treatment effect and stability of the entire softening system, and reducing the operating cost at the same time.

[0018] Furthermore, the aeration unit introduces external air into the hardness removal reaction clarifier. The generated bubbles will drive the water body to flow during the rising process, forming turbulence, which helps the chemicals such as softening agent, alkalizing agent, and eliminator to be fully mixed with calcium and magnesium ions, harmful substances, etc. in the water, enabling the chemicals to be more evenly distributed in the water, increasing the reaction contact area, accelerating the reaction rate, and at the same time accelerating the conversion of bicarbonate formed during the calcium carbonate formation process into carbon dioxide, promoting the forward progress of the hardness removal precipitation reaction.

[0019] Furthermore, the multi-media filter media usually consists of filter media with different particle sizes and materials, such as quartz sand, anthracite, etc. When the liquid flows through the filter, larger particle impurities are first intercepted by the upper layer of filter media with large particle sizes, and smaller particles gradually penetrate deeper with the water flow and are further intercepted by the lower layer of filter media with small particle sizes. This way of stratified filtration can achieve precise interception of impurities with different particle sizes and greatly improve the turbidity removal efficiency.

[0020] Furthermore, the chelating resin for hardness removal contains special chelating groups and can form stable chelates with calcium ions and magnesium ions. When the liquid containing calcium and magnesium ions flows through the ion exchange hardness removal device, the calcium and magnesium ions will undergo an exchange reaction with the exchangeable ions on the resin and be firmly adsorbed by the chelating resin, thereby achieving the ultimate removal of calcium and magnesium ions.

[0021] The present invention also provides a method for using a softening system for removing scaling ions from high-concentration scale inhibitor concentrated water. The concentrated water with high salinity and high scale inhibitor content is input into the chemical dosing softening and clarification unit group. Through chemical dosing reaction and clarification, suspended solids, colloids and other impurities in the concentrated water are removed. The clarified liquid enters the filter to further remove fine particles and impurities in the liquid and reduce the liquid turbidity. The liquid after filtration and turbidity removal enters the ion exchange hardness removal device, and the chelating resin for hardness removal is used to perform ion exchange on calcium ions and magnesium ions in the liquid to achieve ultimate removal.

[0022] Furthermore, a longer hydraulic retention time can ensure that the concentrated water and the added chemicals have enough time for sufficient mixing and chemical reactions. At the same time, it can ensure that the flocs have enough time to settle to the bottom of the clarifier under the action of gravity to form a stable sludge layer, thus ensuring the quality of the supernatant.

[0023] Furthermore, the ion exchange hard removal device is a key equipment for removing scale-forming metal ions such as calcium and magnesium in liquids. Its core component is the chelating resin filled in the device for hard removal, which realizes the selective adsorption and removal of metal ions through the ion exchange principle. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of a softening system for removing scale-forming ions from highly concentrated water of a high-scale inhibitor in an embodiment of the present invention; In the figure: 1. Silicon removal reaction clarifier; 11. Silicon removal agent dosing unit; 12. First eliminator dosing unit; 13. First flocculant dosing unit; 14. First coagulant aid dosing unit; 2. Hard removal reaction clarifier; 21. Alkalizing agent dosing unit; 22. Softening agent dosing unit; 23. Second flocculant dosing unit; 24. Second coagulant aid dosing unit; 25. Second eliminator dosing unit; 26. Aeration unit; 27. Acidifying agent dosing device; 3. Filter; 31. Multi-media filtration media; 4. Ion exchange hard removal device; 41. Chelating resin for hard removal. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below 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 of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] The purpose of the present invention is to provide a softening system and method for removing scale-forming ions from highly concentrated water of a high-scale inhibitor, so as to solve the technical problems of easy scaling, blockage and inefficiency of heat exchange tubes that are extremely likely to occur in the evaporation crystallization process in the prior art.

[0027] The present invention will be further described in detail below with reference to the accompanying drawings: Embodiment 1 Refer to Figure 1 , in an embodiment of the present invention, a softening system for removing scale-forming ions from highly concentrated water of a high-scale inhibitor is provided, including a dosing softening clarification unit group, a filter 3, and an ion exchange hard removal device 4; the input end of the dosing softening clarification unit group is used to input highly concentrated water with high salinity and high-scale inhibitor content; the output end of the dosing softening clarification unit group is connected to the input end of the filter 3; the output end of the filter 3 is connected to the input end of the ion exchange hard removal device 4; the output end of the ion exchange hard removal device 4 is connected to the subsequent system.

[0028] Specifically, the chemical dosing softening and clarification unit group includes a primary chemical dosing softening and clarification unit and a secondary chemical dosing softening and clarification unit; the input end of the primary chemical dosing softening and clarification unit is used to input concentrated water with high salinity and high scale inhibitor content; the output end of the primary chemical dosing softening and clarification unit is connected to the input end of the secondary chemical dosing softening and clarification unit; the output end of the secondary chemical dosing softening and clarification unit is connected to filter 3.

[0029] Among them, the primary chemical dosing softening and clarification unit includes a silicon removal reaction clarifier 1 and a first chemical dosing unit group; the first chemical dosing unit group includes a silicon removal agent dosing unit 11, a first scavenger dosing unit 12, a first flocculant dosing unit 13, and a first coagulant aid dosing unit 14; the input end of the silicon removal reaction clarifier 1 is used to input concentrated water with high salinity and high scale inhibitor content; the output end of the silicon removal reaction clarifier 1 is connected to the input end of the secondary chemical dosing softening and clarification unit; the silicon removal agent dosing unit 11, the first scavenger dosing unit 12, the first flocculant dosing unit 13, and the first coagulant aid dosing unit 14 are all connected to the chemical dosing end of the silicon removal reaction clarifier 1.

[0030] In this embodiment, the function of the silicon removal agent dosing unit 11 is to add a silicon removal agent, which reacts chemically with silicon-containing substances such as silicate in the concentrated water to convert silicon into substances that can be precipitated or flocculated. The function of the first scavenger dosing unit 12 is to add a scavenger, which is mainly used to activate the surface activity of metal cations, improve the ability of microcrystals such as calcium silicoaluminate formed by silicon removal to combine and grow, promote the further increase of flocs, and improve the silicon removal efficiency. The function of the first flocculant dosing unit 13 is to add a flocculant, so that tiny particles, colloids and other impurities in the water aggregate to form larger flocs under the action of the flocculant. The flocculant can make the originally dispersed impurity particles aggregate with each other through functions such as electro-neutralization and adsorption bridging. The function of the first coagulant aid dosing unit 14 is to add a coagulant aid to assist the flocculant to better play its role and improve the formation speed and sedimentation performance of flocs. The coagulant aid can improve the structure of the flocs, make them more compact and stable, and accelerate the sedimentation process of the flocs.

[0031] Among them, the secondary chemical dosing softening and clarification unit includes a hardness removal reaction clarifier 2 and a second chemical dosing unit group; the second chemical dosing unit group includes an alkalizing agent dosing unit 21, a softening agent dosing unit 22, a second flocculant dosing unit 23, a second coagulant aid dosing unit 24, a second scavenger dosing unit 25, and an acidifying agent dosing device 27; the input end of the hardness removal reaction clarifier 2 is connected to the output end of the silicon removal reaction clarifier 1; the output end of the hardness removal reaction clarifier 2 is connected to filter 3; the alkalizing agent dosing unit 21, the softening agent dosing unit 22, the second flocculant dosing unit 23, the second coagulant aid dosing unit 24, and the second scavenger dosing unit 25 are all connected to the chemical dosing end of the hardness removal reaction clarifier 2; the acidifying agent dosing device 27 is arranged between the hardness removal reaction clarifier 2 and filter 3.

[0032] In this embodiment, the function of the alkalizing agent dosing unit 21 is to add an alkalizing agent to increase the pH value of the water body and create a suitable alkaline environment for the subsequent softening reaction. For example, during the process of removing hardness ions, some chemical reactions need to be carried out under alkaline conditions. The alkalizing agent can adjust the acidity and alkalinity of the water body and promote the better performance of agents such as softening agents. The function of the softening agent dosing unit 22 is to add a softening agent, which reacts chemically with hardness ions such as calcium and magnesium in the water to form insoluble precipitates, thereby removing the hardness ions in the water. Common softening agents such as sodium ion exchange resin (when added in the form of a chemical agent) can undergo an ion exchange reaction with calcium and magnesium ions and displace them from the water. The function of the second flocculant dosing unit 23 is to add a second flocculant to further aggregate the fine particles generated after the hardening removal reaction to form larger flocs, facilitating sedimentation. The function of the second coagulant aid dosing unit 24 is to assist the second flocculant in functioning and improve the formation speed and sedimentation performance of the flocs. The function of the second eliminator dosing unit 25 is to further reduce the inhibitory dispersion effect of the high-concentration scale inhibitor on scale precipitation substances such as calcium carbonate and magnesium hydroxide. By increasing the ability of small calcium carbonate and magnesium hydroxide microcrystals formed by calcium and magnesium removal to combine and grow, and at the same time activating the surface activity of metal cations, it promotes the further enlargement of the flocs, improves the hardening removal efficiency, and ensures that the effluent quality meets the requirements. The function of the acidifying agent dosing device 27 is to be arranged between the hardening removal reaction clarifier 2 and the filter 3 to readjust the water treated by the hardening removal reaction clarifier 2. For example, if the previous treatment causes a change in the pH value of the water body, the acidifying agent can adjust it back, and at the same time, it may remove some metal ion residues generated by dosing.

[0033] Among them, the hardening removal reaction clarifier 2 is also connected to an aeration unit 26, which is used to arrange external air inside the hardening removal reaction clarifier 2 to accelerate the forward progress of the hardening removal reaction.

[0034] Specifically, the filter 3 is filled with a multi-media filtration filter material 31, which is used to filter and remove turbidity from the liquid.

[0035] Specifically, the ion exchange hardening removal device 4 is filled with chelating resin 41 for hardening removal, which is used to achieve the ultimate removal of calcium ions and magnesium ions in the liquid through ion exchange.

[0036] In summary, this embodiment provides a softening system for removing scaling ions from high-scale-inhibitor concentrated water. Through the sequential treatment of the chemical dosing softening clarification unit group, filter 3, and ion exchange hard removal device 4, the scaling ions in the concentrated water with high salinity and high scale inhibitor content are effectively removed, the hardness components in the water are significantly reduced, and the possibility of scaling ions depositing on the surface of the heat exchange tubes to form a scale layer during the concentration evaporation crystallization process is reduced. Thereby, the occurrence of heat exchange tube scaling is avoided, and the normal heat transfer performance of the heat exchange tubes is ensured. It effectively realizes the hierarchical precipitation removal and ultimate removal of main scaling ions such as calcium ions, magnesium ions, and silicate ions, and effectively ensures the reliable and stable operation of subsequent thermal concentration-evaporation crystallization.

[0037] Example 2 This embodiment also provides a method for using a softening system for removing scaling ions from high-scale-inhibitor concentrated water. Based on the above-mentioned softening system for removing scaling ions from high-scale-inhibitor concentrated water, it includes: The concentrated water with high salinity and high scale inhibitor content enters the silicon removal reaction clarifier 1. Among them, the silicon removal agent dosing unit 11, the first eliminator dosing unit 12, the first flocculant dosing unit 13, and the first coagulant aid dosing unit 14 are respectively connected to the silicon removal reaction clarifier 1. The silicon removal agent uses inorganic sodium aluminate or magnesium oxide, the eliminator uses organic didodecyldimethylammonium bromide, the flocculant uses polyferric sulfate or aluminum chloride, and the coagulant aid uses polyacrylamide; The effluent of the silicon removal reaction clarifier 1 enters the hard removal reaction clarifier 2. Among them, the alkalizing agent dosing unit 21, the softening agent dosing unit 22, the second flocculant dosing unit 23, the second coagulant aid dosing unit 24, and the second eliminator dosing unit 25 are respectively connected to the hard removal reaction clarifier 2. The alkalizing agent uses sodium hydroxide, the softening agent uses sodium carbonate, the flocculant uses polyferric sulfate or aluminum chloride, the coagulant aid uses polyacrylamide, and the eliminator uses organic didodecyldimethylammonium bromide; The bottom of the hard removal reaction clarifier 2 is connected to the aeration unit 26, and external air is evenly and effectively arranged inside the reactor through the bottom aeration device; The effluent of the hard removal reaction clarifier 2 is connected to the acidifying agent dosing device 27. The acidifying agent uses sulfuric acid or hydrochloric acid; The acidified effluent enters the filter 3, which is filled with multi-media filtration media 31 for further filtering and turbidity removal of the effluent; The effluent of the filter 3 enters the ion exchange hard removal device 4, which is filled with chelating resin 41 for hard removal to further achieve the ultimate removal of calcium ions and magnesium ions in the effluent through ion exchange.

[0038] In this embodiment, the hydraulic retention time of the silicon removal reaction clarifier 1 is not less than 30 min, the dosing amount of the eliminator is 5 - 10 mg / L, the dosing amount of the flocculant is 5 - 10 mg / L, and the dosing amount of the coagulant aid is 0.1 - 0.2 mg / L; In this embodiment, the hydraulic retention time of the hard reaction clarifier 2 is not less than 30 min, the dosage of the scavenger is 10 - 20 mg / L, the dosage of the flocculant is 3 - 8 mg / L, the dosage of the coagulant aid is 0.4 - 0.6 mg / L, and the dosage of sodium carbonate is 1.0 times the equivalent concentration of calcium ions in water. The reaction pH is controlled at 10.8 - 11.2 by the alkalizing agent, and the aeration volume is 0.15 - 0.25 m 3 / h; the scale inhibitor scavenger used is the organic dodecyl dimethyl ammonium halide.

[0039] In this embodiment, the chelating resin 41 for dehardening is a macroporous styrene-based resin, and its main functional group is the iminodiacetic acid group, which can form stable chelates with metal ions in the solution to achieve removal; after the resin is saturated by adsorption, its ion exchange performance can be restored by external acid-base regeneration.

[0040] In this embodiment, under the working conditions of about 120 mg / L of calcium ions, about 60 mg / L of magnesium ions, and about 100 mg / L of silicon content in the concentrated water, the silicon content in the effluent of the silicon removal reactor clarifier 1 can be lower than 10.0 mg / L, and the total hardness of the effluent of the ion exchange dehardening device can be lower than 1.0 mg / L, meeting the inlet water requirements of the thermal concentration system, and effectively solving the problems such as scaling, blockage, and inefficiency of the heat exchange tubes that are prone to occur during the evaporation crystallization process.

[0041] In this embodiment, the method of stepwise silicon removal and dehardening is adopted to effectively remove the scale-forming ions; at the same time, in order to solve the hindrance of the high-concentration scale inhibitor in the concentrated water to the precipitation of scale-forming substances such as calcium carbonate, the scale inhibitor scavenger is added to provide the precipitation crystal nuclei of scale-forming substances such as calcium carbonate, effectively overcoming the influence of the scale inhibitor and improving the dehardening efficiency and effect.

[0042] In the silicon removal reaction clarifier 1, sodium aluminate or oxidase is added as the silicon removal agent, and the flocculant and coagulant aid are supplemented to improve the flocculation effect, and the silicate radical is removed by forming scale-forming substances such as calcium aluminosilicate; and the scale inhibitor scavenger dodecyl dimethyl ammonium bromide is added synchronously to overcome the hindrance ability of the scale inhibitor to the formation of scale-forming substances such as light calcium aluminosilicate; In the hard reaction clarifier 2, sodium hydroxide and sodium carbonate are added as softening agents, and the flocculant and coagulant aid are supplemented to improve the flocculation effect, and calcium ions and magnesium ions are removed by forming scale-forming substances such as calcium carbonate and magnesium hydroxide; and the scale inhibitor scavenger dodecyl dimethyl ammonium bromide is added synchronously as the nucleation core of scale-forming substances such as calcium carbonate to strengthen the dehardening effect; at the same time, an external aeration device is set in the clarifier, and through the uniform aeration of external air, the air introduced makes the associated carbon dioxide of calcium carbonate escape faster, increasing the reaction efficiency and accelerating the formation of calcium carbonate precipitation, effectively improving the dehardening efficiency and effect.

[0043] In the filter 3 and the ion exchange hard removal device 4, the turbidity of water is reduced by the filter 3, and the ultimate hard removal is further achieved through the chelating resin in the ion exchange. The functional groups on the surface of the ion exchange effectively fix and remove the remaining metal ions in the water through chelating adsorption, ion exchange, etc., greatly improving the hard removal efficiency of the system.

[0044] In summary, the present invention also provides a method for using a softening system for removing scale-forming ions from highly concentrated scale inhibitor wastewater. By stepwise setting up the silicon removal reaction clarifier 1, the hard removal reaction clarifier 2, and the ion exchange chelating resin hard removal device, the fractional precipitation and removal and the ultimate removal of the main scale-forming ions such as calcium ions, magnesium ions, and silicate ions are effectively achieved, effectively ensuring the reliable and stable operation of the subsequent thermal concentration-evaporation crystallization.

[0045] By stepwise adding a scale inhibitor eliminator in the silicon and hard removal reaction clarifier 2, it can serve as the nucleation core of scale-forming components such as calcium carbonate, and then form scale-forming crystals, overcoming the complexation, encapsulation, and dispersion effects of the high-concentration scale inhibitor in the concentrated wastewater on scale-forming components such as calcium carbonate. At the same time, by setting up an aeration device in the hard removal reactor, the carbon dioxide associated with the formation of calcium carbonate can be accelerated to overflow through the introduced air, increasing the reaction efficiency, accelerating the formation of calcium carbonate precipitation, effectively improving the hard removal efficiency and effect, and ensuring the reliability of zero discharge of the concentrated wastewater.

[0046] By stepwise setting up devices such as the silicon removal, hard removal reaction clarifier 2, filter, and chelating resin ion exchange, and simultaneously adding an additional scale inhibitor eliminator in the reaction clarifier and setting up an internal aeration device, the precipitation behavior effect of scale-forming ions in the high-concentration scale inhibitor and high-salt environment is improved. Through the fractional precipitation of silicon and hard removal and the ion exchange ultimate hard removal, the reliability of the hard removal system is achieved; by setting up a scale inhibitor eliminator and strengthening aeration, the effective nucleation, crystallization, and precipitation of scale-forming substances are realized, overcoming the problems of scale inhibition by scale inhibitors and the difficulty of efficient hard removal, and finally realizing the stable operation of the subsequent zero-discharge system for thermal concentration and evaporation crystallization of concentrated wastewater.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent replacements can still be made to the specific implementation manners of the present invention, and any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the protection scope of the claims of the present invention.

Claims

1. A softening system for removing scale-forming ions from high-concentration scale inhibitor wastewater, characterized in that, It includes a chemical dosing softening and clarification unit group, a filter (3), and an ion exchange hard removal device (4); The input end of the chemical dosing softening and clarification unit group is used to input concentrated water with high salinity and high scale inhibitor content; the output end of the chemical dosing softening and clarification unit group is connected to the input end of the filter (3); The output end of the filter (3) is connected to the input end of the ion exchange hard removal device (4).

2. The softening system for removing scaling-causing ions from the concentrated water of a high-scale inhibitor, according to claim 1, is characterized in that The chemical dosing softening and clarification unit group includes a primary chemical dosing softening and clarification unit and a secondary chemical dosing softening and clarification unit; The input end of the primary chemical dosing softening and clarification unit is used to input concentrated water with high salinity and high scale inhibitor content; The output end of the primary chemical dosing softening and clarification unit is connected to the input end of the secondary chemical dosing softening and clarification unit; The output end of the secondary chemical dosing softening and clarification unit is connected to the filter (3).

3. The softening system for removing scaling-causing ions from high-concentration scale inhibitor wastewater according to claim 2, wherein, The primary chemical dosing softening and clarification unit includes a silicon removal reaction clarifier (1) and a first chemical dosing unit group; The first chemical dosing unit group includes a silicon removal agent dosing unit (11), a first scavenger dosing unit (12), a first flocculant dosing unit (13), and a first coagulant aid dosing unit (14); The input end of the silicon removal reaction clarifier (1) is used to input concentrated water with high salinity and high scale inhibitor content; The output end of the silicon removal reaction clarifier (1) is connected to the input end of the secondary chemical dosing softening and clarification unit; The silicon removal agent dosing unit (11), the first scavenger dosing unit (12), the first flocculant dosing unit (13), and the first coagulant aid dosing unit (14) are all connected to the chemical dosing end of the silicon removal reaction clarifier (1).

4. A softening system for removing scale-forming ions from high-scale inhibitor concentrated water according to claim 3, characterized in that, The secondary chemical dosing softening and clarification unit includes a hard removal reaction clarifier (2) and a second chemical dosing unit group; The second chemical dosing unit group includes an alkalizing agent dosing unit (21), a softening agent dosing unit (22), a second flocculant dosing unit (23), a second coagulant aid dosing unit (24), a second scavenger dosing unit (25), and an acidifying agent dosing device (27); The input end of the hard removal reaction clarifier (2) is connected to the output end of the silicon removal reaction clarifier (1); The output end of the hard removal reaction clarifier (2) is connected to the filter (3); The alkalizing agent dosing unit (21), the softening agent dosing unit (22), the second flocculant dosing unit (23), the second coagulant aid dosing unit (24), and the second scavenger dosing unit (25) are all connected to the chemical dosing end of the hard removal reaction clarifier (2); The acidifying agent dosing device (27) is arranged between the hard removal reaction clarifier (2) and the filter (3).

5. A softening system for removing scaling-causing ions from high-concentration scale inhibitor wastewater according to claim 4, characterized in that, The hard removal reaction clarifier (2) is further connected to an aeration unit (26) for arranging external air inside the hard removal reaction clarifier (2).

6. The softening system for removing scale-forming ions from high-scale inhibitor concentrated water according to claim 1, characterized in that, The filter (3) is filled with multi-media filtration media (31) for filtering and removing turbidity from the liquid.

7. The softening system for removing scale-forming ions from the concentrated water of a high-scale inhibitor, according to claim 1, is characterized in that The ion exchange hard removal device (4) is filled with chelating resin for hard removal (41) for achieving ultimate removal of calcium ions and magnesium ions in the liquid through ion exchange.

8. A method for using a softening system for removing scale-forming ions from high-concentration scale inhibitor wastewater, based on the softening system for removing scale-forming ions from high-concentration scale inhibitor wastewater according to any one of claims 1-7, characterized in that, It includes: After inputting the concentrated water with high salinity and high scale inhibitor content into the chemical dosing softening and clarification unit group for clarification, it is input into the filter (3) for filtering and removing turbidity; The liquid after filtration and turbidity removal enters the ion exchange hard removal device (4), and the calcium ions and magnesium ions in the liquid are removed to the limit through ion exchange, completing the work of removing scale-forming ions from the high-scale inhibitor concentrated water.

9. The usage method of a softening system for removing scale-forming ions from high-scale inhibitor concentrated water according to claim 8, characterized in that, The chemical addition softening clarification unit group includes a primary chemical addition softening clarification unit and a secondary chemical addition softening clarification unit, and the hydraulic retention time of the primary chemical addition softening clarification unit and the secondary chemical addition softening clarification unit is not less than 30 min.

10. The usage method of a softening system for removing scale-forming ions from high-scale inhibitor concentrated water according to claim 8, characterized in that, The ion exchange hard removal device (4) is filled with chelating resin (41) for hard removal. The chelating resin (41) for hard removal is a macroporous styrene resin, and the group of the macroporous styrene resin is an iminodiacetic acid group. The chelating resin (41) for hard removal forms a chelate with metal ions in the liquid, and the removal is achieved through the chelate; when the chelating resin (41) for hard removal is saturated by adsorption, its ion exchange performance can be restored by external acid-base regeneration.

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