A process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system

Abstract

The present invention relates to a process for treating ammonia-nitrogen-containing wastewater by utilizing a magnetic separation wastewater system. The magnetic separation wastewater system comprises a magnetic separation unit and is characterized in that the magnetic separation wastewater system further comprises an adsorption reaction unit, wherein the adsorption reaction unit comprises an adsorption reaction box, the adsorption reaction box is provided with an adsorption cavity, and the adsorption cavity is connected to the downstream magnetic separation unit. The process comprises: step S1, using a magnetic composite material with an ammonia-nitrogen adsorption function as a magnetic medium, inputting the magnetic medium and the wastewater together into the adsorption reaction unit, and achieving mixing of the magnetic medium and the wastewater in the adsorption cavity and completing adsorption of soluble ammonia-nitrogen in the wastewater; step S2, continuing to input the wastewater into the magnetic separation unit, continuing to treat the wastewater by utilizing a magnetic separation process, and at least removing insoluble pollutants in the wastewater; the process can simultaneously remove soluble ammonia-nitrogen and insoluble pollutants in the wastewater through a single magnetic separation process.

Description

Technical Field

[0001] The present invention relates to the technical field of ammonia nitrogen-containing wastewater treatment technology, and in particular to a technology for treating ammonia nitrogen-containing wastewater by utilizing a magnetic separation wastewater system. Background Art

[0002] Magnetic separation technology is a physical separation method that uses magnetic field forces to separate substances with different magnetic properties. It was first used in the mineral processing industry, with the United States patenting an industrial magnetic separator in 1845. Magnetic separation, in the form of mechanical equipment, has since been widely used in fields beyond mineral processing, such as coal desulfurization, iron removal from raw materials like glass and cement, and kaolin purification. In the 1960s, the Soviet Union used magnetic coagulation to treat steel mill dust removal wastewater, marking the beginning of the application of magnetic separation technology in water treatment. In the 1970s, the United States, Japan, and other countries began using HGMS high-gradient magnetic filters for metallurgical wastewater treatment.

[0003] Magnetic separation processes (magnetic separation wastewater treatment processes), represented by supermagnetic separation and magnetic precipitation, all utilize magnetic loading flocculation technology. The addition of magnetic media (or magnetic seeds) significantly enhances the flocculation effect. Existing technologies indicate that existing magnetic separation processes can directly remove pollutants such as suspended solids, TP, insoluble COD, and heavy metals from water bodies through coagulation. However, soluble pollutants such as ammonia nitrogen, TN, and soluble COD cannot be directly removed through coagulation. For example, for wastewater rich in ammonia nitrogen, ammonia nitrogen is usually dissolved in the wastewater, and the existing magnetic separation process alone cannot effectively remove the dissolved ammonia nitrogen. In the prior art, in order to remove the solubility index in the wastewater (such as ammonia nitrogen dissolved in the wastewater), it is usually only possible to configure a biochemical process downstream of the magnetic separation process so that the magnetic separation process can cooperate with the biochemical process. In actual operation, the magnetic separation process is mainly used to remove suspended matter, TP insoluble COD and heavy metals and other pollutants in the water body. The biochemical process configured downstream of the magnetic separation process is mainly used to remove the solubility index in the water body and has a certain effect. However, this combined method requires the entire wastewater treatment process to be configured with a magnetic separation process and a biochemical process at the same time, which not only makes the overall process flow more complicated and more costly, but also the biochemical process itself has some disadvantages. For example, the existing biochemical process is usually greatly affected by the ambient temperature, the microbial culture cycle is long, and the effluent index is difficult to control. Problems such as these make it difficult for the effluent to meet the standards need to be solved urgently. Therefore, a simpler and more effective means is needed to solve the problem that the existing magnetic separation process cannot remove soluble ammonia nitrogen in wastewater, resulting in a high ammonia nitrogen content in the effluent after the existing magnetic separation process treats ammonia nitrogen-rich wastewater. Summary of the Invention

[0004] The first aspect of the present invention aims to solve the problem that the existing magnetic separation process can only remove insoluble pollutants such as suspended matter, TP insoluble COD and heavy metals in water, but cannot remove solubility indicators such as dissolved ammonia nitrogen in water. A process is provided that can remove pollutants such as suspended matter, TP insoluble COD and heavy metals in water, and can also remove dissolved ammonia nitrogen in water. It can simplify the existing process flow, avoid the technical problems caused by the biochemical process, and significantly reduce the ammonia nitrogen content in the effluent. The main concept is:

[0005] A process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system, wherein the magnetic separation wastewater system comprises a magnetic separation unit,

[0006] The magnetic separation wastewater system also includes an adsorption reaction unit, which includes an adsorption reaction box. The adsorption reaction box is equipped with an adsorption cavity, which is connected to the downstream magnetic separation unit. The process includes:

[0007] Step S1: Using a magnetic composite material with ammonia nitrogen adsorption function as a magnetic medium, the magnetic medium and wastewater are fed into an adsorption reaction unit, and the magnetic medium and wastewater are mixed in the adsorption cavity to complete the adsorption of dissolved ammonia nitrogen in the wastewater;

[0008] In step S2, the wastewater is further input into the magnetic separation unit, and the magnetic separation process is used to continue to treat the wastewater, at least to remove the insoluble pollutants in the wastewater. In this solution, by using a magnetic composite material with ammonia nitrogen adsorption function as a magnetic medium, the magnetic medium can not only remove insoluble pollutants such as suspended matter, TP, insoluble COD, and heavy metals in the wastewater using the magnetic separation process in the magnetic separation unit, but also can undergo adsorption reaction with the wastewater in the adsorption reaction unit to effectively remove dissolved ammonia nitrogen in the wastewater, so that the process can simultaneously remove pollutants such as dissolved ammonia nitrogen and insoluble pollutants in the wastewater through a single treatment process. On the one hand, there is no need to use it in conjunction with the existing biochemical process, which can simplify the existing process flow and avoid the technical problems brought about by the biochemical process. On the other hand, the effluent ammonia nitrogen content can be significantly reduced, which is particularly suitable for treating wastewater rich in ammonia nitrogen. In addition, the adsorption and separation time is short during the entire process, which is conducive to improving the efficiency of sewage treatment.

[0009] To address the issues of high adsorption capacity and easy regeneration, the magnetic composite material preferably includes a porous carrier with the chemical formula Na2Al2Si2O8·nH2O and SmCo5 particles and Fe3O4 particles present within the pores of the porous carrier, wherein n ≥ 0, and the mass percentages of SmCo5:Fe3O4:carrier are 0.4-10%:30-50%:50-70%; the pore diameter is 0.35-0.45 nm. This newly developed magnetic composite material exhibits improved adsorption and ion exchange properties, and features higher adsorption capacity, shorter adsorption time, and higher adsorption efficiency. It can not only be used to adsorb dissolved ammonia nitrogen in wastewater, but is also easily regenerated, allowing it to be recycled and reused, significantly improving economic efficiency.

[0010] In order to improve the effect of adsorbing ammonia nitrogen, the adsorption reaction unit further includes an adsorption reaction box, which is equipped with at least two adsorption cavities connected in series, and the last adsorption cavity is connected to the magnetic separation unit; S1 also includes a step of allowing the wastewater and the magnetic medium to pass through each adsorption cavity in turn, and achieving mixing and completing the adsorption of ammonia nitrogen during the passing process.

[0011] To ensure thorough mixing of the magnetic medium and wastewater within the adsorption reaction unit, the adsorption reaction unit further includes a stirrer disposed within each adsorption cavity. This allows for thorough and uniform mixing of the magnetic medium and wastewater, thereby facilitating full contact between the magnetic medium and ammonia nitrogen in the wastewater, thereby further facilitating adsorption of ammonia nitrogen in the wastewater.

[0012] In order to solve the problem of improving the adsorption efficiency, preferably, in step S1, the mixing time of the magnetic medium and the wastewater in the adsorption reaction unit is 15-25 minutes.

[0013] Preferably, the magnetic separation unit includes a magnetic coagulation reaction device and a magnetic separation device, the adsorption reaction unit is connected to the magnetic coagulation reaction device, the magnetic separation device is arranged downstream of the magnetic coagulation reaction device and is connected to the magnetic coagulation reaction device, the magnetic separation device includes a mud discharge end and a water discharge end, and the S2 includes,

[0014] S2.1, adding an appropriate amount of reagent to the wastewater after mixing with the magnetic medium in the magnetic coagulation reaction device, and forming magnetic flocs in the wastewater through magnetic coagulation reaction;

[0015] S2.2, the magnetic separation equipment uses a magnetic field to separate magnetic flocs from wastewater, forming magnetic sludge. The magnetic sludge is discharged through the sludge discharge port, and the water after the magnetic flocs are separated is discharged through the drainage port. The magnetic separation unit is used to implement a magnetic separation process to remove pollutants such as suspended solids, TP, insoluble COD, and heavy metals from wastewater.

[0016] Preferably, the magnetic separation equipment is a supermagnetic separator or a magnetic precipitation device.

[0017] Preferably, in S2.1, the added agent is a coagulant and / or a flocculant.

[0018] In order to solve the problem of improving the coagulation effect and efficiency, preferably, in S2.1, the magnetic coagulation reaction time in the magnetic coagulation reaction device is 3-5 minutes.

[0019] Preferably, the magnetic coagulation reaction device is constructed with at least a coagulation chamber and a flocculation chamber that are interconnected, the adsorption reaction unit is connected to the coagulation chamber, and the flocculation chamber is connected to the magnetic separation device, and S2.1 further includes the steps of adding an appropriate amount of coagulant into the coagulation chamber and adding an appropriate amount of flocculant into the flocculation chamber, so as to effectively separate the magnetic sludge in the wastewater.

[0020] In order to solve the problem of improving the economic efficiency of this process, preferably, the magnetic separation wastewater system further includes a regeneration circulation unit arranged downstream of the magnetic separation unit and connected to the magnetic separation unit, and the process further includes:

[0021] S3: The regeneration and circulation unit receives the magnetic sludge separated by the magnetic separation unit and adds an appropriate amount of regeneration agent to the separated magnetic sludge. The regeneration agent then exchanges the ammonia and nitrogen ions adsorbed by the magnetic medium within the magnetic sludge, thereby obtaining a magnetic medium free of ammonia and nitrogen. In this solution, the regeneration and circulation unit is configured to separate and restore the magnetic composite material from the magnetic sludge, allowing the magnetic composite material to regain its ability to adsorb ammonia and nitrogen, thereby facilitating the recycling of the magnetic medium. This significantly reduces operating costs and improves economic efficiency.

[0022] The second aspect of the present invention is to solve the problem of low-cost, high-efficiency reduction and regeneration of magnetic media. Furthermore, the regeneration circulation unit includes a primary magnetic recovery device, a regeneration agent dosing device and a regeneration reactor. The regeneration reactor is configured with a reaction chamber for providing a reaction site. The mud discharge end of the magnetic separation device is connected to the primary magnetic recovery device, and the primary magnetic recovery device and the regeneration agent dosing device are respectively connected to the reaction chamber; step S3 includes,

[0023] S3.2, using a primary magnetic recovery device to separate magnetic material from the magnetic sludge, and inputting the separated magnetic material into the reaction chamber of the regeneration reactor;

[0024] S3.3, using a regenerant dosing device to add an appropriate amount of regenerant to the reaction chamber of the regeneration reactor. The regenerant mixes and reacts with the magnetic material in the reaction chamber to reduce the magnetic medium after ammonia nitrogen adsorbed in the magnetic material. In this solution, by configuring a primary magnetic recovery device within the regeneration circulation unit, the primary magnetic recovery device can be used to separate the magnetic material from the non-magnetic sludge in the magnetic sludge, so that the separated magnetic material can be treated separately later, avoiding interference from the sludge. On the one hand, this helps to reduce the amount of regenerant added, thereby reducing costs. On the other hand, it allows the regenerant and magnetic material to more fully contact and react, thereby facilitating the efficient reduction and regeneration of the magnetic medium.

[0025] In order to solve the problem of improving the recovery rate of magnetic substances in magnetic sludge, the regeneration cycle unit further includes a first deflocculator, which is connected to the sludge discharge end of the magnetic separation device and the first magnetic recovery device respectively; step S3 also includes

[0026] S3.1: The first deflocculant physically crushes the magnetic sludge discharged from the sludge discharge port. The crushed magnetic sludge is then fed into the primary magnetic recovery unit. Physically crushing the magnetic sludge first breaks up the magnetic flocs within the sludge, allowing for better separation of the magnetic media from the sludge in the primary magnetic recovery unit. This improves the recovery rate of the magnetic media in the sludge and reduces the residual magnetic media content in the sludge, thus reducing operating costs and promoting energy conservation and environmental protection.

[0027] To address the problem of reducing and regenerating the magnetic medium, preferably, in S3.3, the regeneration agent contains sodium ions, and the sodium ions in the regeneration agent are used to exchange the ammonia nitrogen ions adsorbed by the magnetic medium. This allows the sodium ions to re-enter the magnetic composite material, achieving the purpose of reducing and regenerating the magnetic composite material, allowing the magnetic medium to regain the ability to adsorb ammonia nitrogen, thereby allowing the magnetic medium to be reused and recycled.

[0028] In order to solve the problem of not introducing new pollutants into the wastewater, preferably, the regeneration agent is NaCl solution and / or NaOH solution.

[0029] The third aspect of the present invention is to solve the problem of automatic regeneration of magnetic media. Furthermore, the magnetic separation wastewater system also includes a controller and a monitoring module for monitoring the quality of the magnetic material in the reaction chamber, and the regeneration reactor also includes a discharge mechanism adapted to the reaction chamber, wherein:

[0030] The first-stage magnetic recovery device is connected to the main conveying channel, which is connected to the reaction chamber. The main conveying channel is equipped with a feed pump.

[0031] The regeneration agent dosing device is connected to the reaction chamber through the main dosing channel, and the main dosing channel is equipped with a dosing power.

[0032] The monitoring module, the discharge mechanism, the feed pump, and the dosing power are electrically connected to the controller, respectively. The process also includes a method for automatically regenerating the magnetic medium, including: when the discharge mechanism is in a closed state, the controller controls the feed pump to input magnetic material into the reaction chamber, and during this process, the monitoring module is used to monitor the amount of magnetic material in the reaction chamber; at the same time, the controller controls the regenerant dosing device to synchronously add regenerant to the reaction chamber, so that the magnetic material and the regenerant contact and react in the reaction chamber;

[0033] When the monitoring module detects that the amount of magnetic material in the reaction chamber reaches the set threshold, the controller controls the feed pump and the dosing power to be turned off, and records the duration of the dosing power or feed pump being turned off, so as to reserve time for the reaction between the magnetic material and the regeneration agent;

[0034] When the time reaches a set threshold, the controller can control the discharge mechanism to empty the reaction chamber. Finally, the controller controls the discharge mechanism to close, completing a regeneration process of the magnetic medium, and repeating the cycle.

[0035] The fourth aspect of the present invention is to solve the problem of continuous regeneration of magnetic media. Further, the regeneration reactor is configured with at least two reaction chambers. The magnetic separation wastewater system also includes a controller and a monitoring module for monitoring the quality of magnetic substances in each reaction chamber. The regeneration reactor also includes a discharge mechanism adapted to each reaction chamber, wherein:

[0036] The primary magnetic recovery device is connected to the main conveying channel, which is connected to at least two sub-conveyor channels. The main conveying channel is equipped with a feed pump. Each sub-conveyor channel is connected to each reaction chamber, and each sub-conveyor channel is provided with a feed switch. The controller is electrically connected to each feed switch to control the on and off of each feed switch.

[0037] The regeneration agent dosing device is connected to the main dosing channel, which is connected to at least two sub-dosing channels. The main dosing channel is equipped with a dosing power source. Each sub-dosing channel is connected to each reaction chamber, and each sub-dosing channel is provided with a dosing switch. The controller is electrically connected to each dosing switch for controlling the on and off of each dosing switch.

[0038] The monitoring module, each discharge mechanism, each feed switch and each dosing switch are electrically connected to the controller respectively. The controller is used to control the sequential and cyclic delivery of magnetic substances to each reaction chamber, the sequential and cyclic addition of regeneration agents to each reaction chamber, and the sequential and cyclic emptying of each reaction chamber.

[0039] The fifth aspect of the present invention is to solve the problem of reflowing pure magnetic medium. Further, the regeneration cycle unit also includes a secondary magnetic recovery device, which is connected to the regeneration reactor and the secondary magnetic recovery device is connected to the adsorption reaction unit; the step S3 also includes

[0040] S3.4, the mixture after the reaction in the regeneration reactor is input into a secondary magnetic recovery device, and the magnetic medium in the mixture is separated by the magnetic field within the secondary magnetic recovery device. By configuring the secondary magnetic recovery device, it can be coordinated with the primary magnetic recovery device to achieve two-stage magnetic recovery and avoid the influence of excessive regeneration agent. In order to obtain pure and adsorbable magnetic medium through two-stage magnetic recovery, when the magnetic medium is refluxed, no new pollutants are introduced into the wastewater. Moreover, since only the magnetic medium is refluxed, it is beneficial to accurately control the amount of magnetic medium added to the adsorption reaction unit, which is beneficial to improve the water output effect.

[0041] In order to solve the problem of improving the recovery rate of the magnetic medium in the mixture, the regeneration circulation unit further includes a second deflocculator, which is respectively connected to the regeneration reactor and the secondary magnetic recovery device; S3.4 also includes the steps of inputting the mixture after the reaction in the regeneration reactor into the second deflocculator, using the second deflocculator to physically crush the mixture, and then inputting the physically crushed mixture into the secondary magnetic recovery device. In this solution, the mixture is first physically crushed to break up the magnetic medium in the mixture so that the magnetic medium in the mixture can be better separated in the secondary magnetic recovery device, which can significantly improve the recovery rate of the magnetic medium in the mixture and reduce the content of residual magnetic medium in the mixture, which is beneficial to reducing operating costs and is also beneficial to energy conservation and environmental protection.

[0042] To further address the problem of recycling magnetic media, the regeneration cycle unit also includes a second temporary storage container and a reflux pump. The second temporary storage container is connected to the secondary magnetic recovery device and is used to receive and store the magnetic media separated from the secondary magnetic recovery device. The second temporary storage container is connected to the adsorption reaction unit via a reflux pipe. The reflux pump is connected to the reflux pipe to provide reflux power. The process also includes step S4 of adding the obtained magnetic media to the adsorption reaction unit to achieve circulation. The recovered magnetic media can be transported by the reflux pump and refluxed back to the adsorption reaction unit through the reflux pipe, thereby achieving the purpose of recycling and reusing the magnetic media.

[0043] The sixth aspect of the present invention is to solve the problem of improving the economic efficiency of this process. Furthermore, the magnetic separation wastewater system also includes a regeneration liquid treatment unit, the regeneration liquid treatment unit includes a crystallizer, the crystallizer is connected to the first outlet of the secondary magnetic recovery device, and the first outlet is used to output the mixed liquid after the magnetic medium is separated; the process also includes step S5, inputting the mixed liquid after the magnetic medium is separated in the regeneration reactor into the crystallizer,

[0044] Input appropriate amounts of alkaline solution, MgCl2 and NaH2PO4 into the crystallizer, so that the alkaline solution, MgCl2, NaH2PO4 and the mixed solution react chemically in the crystallizer to generate magnesium ammonium phosphate.

[0045] The generated magnesium ammonium phosphate is separated by precipitation. The separated magnesium ammonium phosphate can be used as a compound fertilizer and has certain economic value, so that the mixed liquid after the magnetic medium is separated in the secondary magnetic recovery device can be fully utilized, thereby significantly improving the economic efficiency of this process.

[0046] Furthermore, the regeneration liquid processing unit further includes a regeneration liquid collection tank for temporarily storing the mixed liquid. The regeneration liquid collection tank is disposed between the secondary magnetic recovery device and the crystallizer. The secondary magnetic recovery device discharges the mixed liquid after separation of the magnetic medium into the regeneration liquid collection tank through a first outlet. The regeneration liquid collection tank then delivers the mixed liquid to the crystallizer via a delivery pump. This allows for controllable delivery of the mixed liquid to the crystallizer.

[0047] Compared with the existing technology, the process for treating ammonia nitrogen-containing wastewater using a magnetic separation wastewater system provided by the present invention does not need to be used in combination with the existing biochemical process, and can effectively remove dissolved ammonia nitrogen in the wastewater during a single magnetic separation wastewater treatment process. It can not only simplify the existing process flow and avoid the technical problems brought about by the biochemical process, but also effectively remove insoluble pollutants after removing the dissolved ammonia nitrogen, thereby significantly reducing the ammonia nitrogen content in the effluent, and is particularly suitable for treating wastewater rich in ammonia nitrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0049] Figure 1 This is a structural schematic diagram of a magnetic separation wastewater system provided in Example 1 of the present invention.

[0050] Figure 2This is a structural schematic diagram of a magnetic separation wastewater system provided in Example 2 of the present invention.

[0051] Figure 3 This is a structural schematic diagram of a magnetic separation wastewater system provided in Example 3 of the present invention.

[0052] Figure 4 This is a structural schematic diagram of a magnetic separation wastewater system provided in Example 4 of the present invention.

[0053] Figure 5 This is a structural schematic diagram of a magnetic separation wastewater system provided in Example 5 of the present invention.

[0054] Figure 6 A process flow chart for treating ammonia-nitrogen-containing wastewater using the magnetic separation wastewater system provided in an embodiment of the present invention.

[0055] Figure 7 A flowchart of a process for treating ammonia-nitrogen-containing wastewater provided in an embodiment of the invention.

[0056] Description of the marks in the figure

[0057] Adsorption reaction unit 100, adsorption reaction box 101, adsorption cavity 102, stirrer 103

[0058] Magnetic separation unit 200, magnetic coagulation reaction device 201, coagulation chamber 202, flocculation chamber 203, PAC dosing device 204, PAM dosing device 206, magnetic separation equipment 207, PAC pump 209, PAM pump 210

[0059] Regeneration circulation unit 300, first deflocculant 301, primary magnetic recovery device 302, first temporary storage container 303, main conveying channel 304, sub-conveying channel 305, feed pump 306, feed switch 307, regeneration reactor 308, regeneration agent dosing device 309, main dosing channel 310, sub-dosing channel 311, dosing power 312, dosing switch 313, second deflocculant 314, secondary magnetic recovery device 315, second temporary storage container 316, discharge channel 317, discharge switch 318, reflux pipe 319, reflux pump 320, conveying pump 321

[0060] Regeneration liquid treatment unit 400, regeneration liquid collection tank 401, crystallizer 402, first container 403, second container 404, third container 405

[0061] Sludge tank 501 and sludge dewatering device 502. DETAILED DESCRIPTION

[0062] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0063] Example 1

[0064] This embodiment provides a process for treating ammonia-nitrogen-containing wastewater using the magnetic separation wastewater system, which is applicable to occasions where a magnetic composite material with ammonia-nitrogen adsorption function is used as a magnetic medium. The magnetic separation wastewater system specifically includes an adsorption reaction unit 100 and a magnetic separation unit 200. The adsorption reaction unit 100 is configured upstream of the magnetic separation unit 200 and is connected to the magnetic separation unit 200. Figure 1 As shown,

[0065] The magnetic separation unit 200 is used to implement the existing magnetic separation process, using magnetic loading flocculation technology to treat wastewater, mainly used to remove insoluble pollutants in the water body. Therefore, during implementation, the magnetic separation unit 200 can adopt an existing magnetic separation system, such as Figure 1 As shown, the magnetic separation unit 200 includes a magnetic coagulation reaction device 201 and a magnetic separation device 207 connected to the magnetic coagulation reaction device 201.

[0066] like Figure 1 As shown, the adsorption reaction unit 100 is connected to the magnetic coagulation reaction device 201, so that the wastewater first flows into the adsorption reaction unit 100 and then flows into the magnetic separation unit 200.

[0067] During implementation, the magnetic composite material can adopt a traditional magnetic composite material that can adsorb ammonia nitrogen. The magnetic composite material used in this embodiment is a newly developed magnetic material, which includes a porous carrier with a chemical formula of Na2Al2Si2O8·nH2O and SmCo5 particles and Fe3O4 particles present in the pores of the porous carrier (which can be abbreviated as: SmCo5-Fe3O4 / Na2Al2Si2O8·nH2O), wherein n≥0, and the mass percentage of SmCo5:Fe3O4:carrier is 0.4~10%:30~50%:50~70%; the pore size is 0.35~0.45nm. The magnetic composite material is a magnetic composite material synthesized by hydrothermal method using iron ions and metakaolin. Its specific preparation process includes S1, mixing FeCl2, FeCl3 and pure water to form a first mixture, wherein the amount of FeCl2 and FeCl3 can be prepared according to the stoichiometric ratio that can generate Fe3O4; S2, adding metakaolin to the first mixture, mixing to form a second mixture, the mass ratio of the added metakaolin to the first solution can be adjusted by technicians at will, for example, it can be 1.5:20; S3, adding NaOH solution to the second mixture, adjusting the pH of the reaction system to 13-14, and then reacting at a temperature of 70-100°C for 0.5-1h to form a third mixture. In this step, after adding NaOH to form the third mixture, Fe 2+ and Fe 3+ React with it to produce Fe3O4, and the metakaolin will also react in an alkaline environment to generate a portion of sodium aluminosilicate substances; S4, then add SmCl3, CoCl2 and NaBH4 to the third mixture for hydrothermal reaction, control the reaction temperature to 60-100°C, the pH to 13-14, and the reaction time to 6-10h, and the obtained solid product is the magnetic composite material; under the hydrothermal conditions, the sodium aluminosilicate substances can undergo hydrothermal crystallization reaction to generate porous molecular sieve Na2Al2Si2O8·nH2O, and the metakaolin that is not completely reacted in step S3 also continues to react with NaOH to generate sodium aluminosilicate substances and then undergoes hydrothermal crystallization reaction to generate porous molecular sieve Na2Al2Si2O8·nH2O, and at the same time, SmCl3, CoCl2 and NaBH4 react according to the following equation in the hydrothermal reaction and co-precipitate:

[0068] 2SmCl3+10CoCl2+12NaBH4+26NaOH→2SmCo5↓+12NaBO2+26NaCl+35H2↑+2H2O

[0069] The newly generated SmCo5 particles and Fe3O4 particles will be deposited in the porous molecular sieve pores, which is the magnetic composite material prepared by the present invention. The reactions in steps S1 to S4 are all carried out under nitrogen or inert gas protection. In the preparation process, the key point is: in order to better combine SmCo5, Fe3O4, and Na2Al2Si2O8, the reaction time must be strictly controlled after the third mixture begins to react for 0.5 to 1 hour, and then SmCl3, CoCl2, and NaBH4 are added. If they are added before 0.5 hours, the adsorption performance of the obtained material will deteriorate; if they are added after more than 1 hour, it will affect the bonding between SmCo5, Fe3O4, and Na2Al2Si2O8. In addition, in order to make the bonding between the crystals tighter, the present invention does not directly add SmCo5, but uses SmCl3, CoCl2, and NaBH4 to make them react and precipitate at the same time, and the precipitation process is synchronized with the construction of the porous structure of the molecular sieve, so that SmCo5 is better distributed in the molecular sieve pores. The prepared magnetic composite material has a structure with SmCo5 and Fe3O4 as the core and Na2Al2Si2O8 as the shell. The magnetic composite material has magnetism and the ability to adsorb ammonia nitrogen, and has good adsorption and ion exchange properties. In this embodiment, the Na2Al2Si2O8 in the magnetic composite material is a molecular sieve, and the unit cell pores of the molecular sieve can adsorb ammonia nitrogen in sewage. The ammonia nitrogen exists in the sewage in the form of ammonium ions. The unit cell pores of the molecular sieve generally have an aperture range of 0.38nm-0.63nm. Molecules and ions larger than this aperture will not be able to enter, and NH4 + The ion diameter is 0.286nm, so the ammonium ions can enter the unit cell pores. + Ionization can be replaced with ammonium ions, and ammonium ions are attracted to the unit cell pores by ionic bonds. The unit cell pores of molecular sieves have very strong polarity and coulombic field, which adsorb the ammonium ions in sewage by physical attraction. Therefore, the magnetic composite material provided by the present invention can adsorb the ammonium ions in sewage by chemical replacement and physical adsorption, thereby achieving better removal effect. In addition, the equilibrium saturated adsorption concentration of the magnetic composite material can even reach 60.0mg of ammonia nitrogen per gram of adsorption, which is very high and can significantly improve the removal efficiency of ammonia nitrogen.

[0070] In this magnetic composite material, the addition of SmCo5 to the core significantly improves the magnetic susceptibility compared to a magnetic composite material using only Fe3O4. For example, taking SmCo5-Fe3O4 / Na2Al2Si2O8·4.5H2O and Fe3O4 / Na2Al2Si2O8·4.5H2O as examples, as shown in Table 1, the comprehensive performance of the magnetic composite material formed by SmCo5 and Fe3O4 is effectively improved, especially the magnetic susceptibility. The proportion of Na2Al2Si2O8·4.5H2O with adsorption properties increases, and the adsorption performance is improved, thereby significantly improving the wastewater treatment effect.

[0071] Table 1 Comparison of the two materials

[0072]

[0073] In this embodiment, the adsorption reaction unit 100 is mainly used to provide a place for the adsorption reaction between the magnetic medium and the wastewater. During implementation, the adsorption reaction unit 100 includes an adsorption reaction box 101, and the adsorption reaction box 101 is provided with an adsorption cavity 102. The adsorption cavity 102 is used to provide a place for the adsorption reaction. During implementation, the number of the adsorption cavity 102 can be one; of course, in order to improve the effect and efficiency of ammonia nitrogen adsorption, in a preferred embodiment, the adsorption reaction box 101 is provided with at least two adsorption cavities 102 connected in series, and the frontmost adsorption cavity 102 is used for water inlet, and the rearmost adsorption cavity 102 is connected to the magnetic coagulation reaction device 201. For example, Figure 1 As shown, the adsorption reaction box 101 is equipped with three adsorption cavities 102 connected in series. Wastewater enters the adsorption reaction box 101 through the first adsorption cavity 102, passes through each adsorption cavity 102 in sequence, and leaves the adsorption reaction box 101 through the last adsorption cavity 102, and enters the downstream magnetic coagulation reaction device 201. Figure 1 As shown, the adsorption reaction unit 100 also includes an agitator 103 arranged in each adsorption cavity 102. The agitator 103 can not only accelerate the mixing of the magnetic medium and the wastewater, but also make the magnetic medium and the wastewater fully and evenly mixed together, thereby facilitating full contact between the magnetic medium and the wastewater, and more conducive to the adsorption of ammonia nitrogen dissolved in the wastewater.

[0074] During implementation, the magnetic coagulation reaction device 201 can adopt an existing magnetic coagulation reaction device 201, for example, Figure 1As shown, the magnetic coagulation reaction device 201 is constructed with at least a coagulation chamber 202 and a flocculation chamber 203 that are interconnected. The coagulation chamber 202 is configured upstream of the flocculation chamber 203. The coagulation chamber 202 is mainly used to provide a place for mixing the coagulant and the wastewater. During implementation, an agitator 103 can be configured in the coagulation chamber 202 to increase the stirring intensity in the coagulation chamber 202 so that the coagulant can be fully and efficiently mixed with the wastewater and a coagulation reaction can occur. Of course, during implementation, a guide tube adapted for the agitator 103 can also be configured in the coagulation chamber 202 to further enhance the mixing effect. During implementation, one or more cavities can also be configured upstream of the coagulation chamber 202 so that the cavity is located between the adsorption reaction box 101 and the coagulation chamber 202 to act as a buffer.

[0075] The flocculation chamber 203 is mainly used to provide a place for mixing the flocculant and the wastewater. Similarly, in order to ensure that the flocculant and the wastewater can be fully and efficiently mixed, during implementation, the flocculation chamber 203 is equipped with a stirrer 103 to increase the stirring intensity in the flocculation chamber 203 so that the flocculant and the wastewater can be fully and efficiently mixed and flocculation reaction can occur. During implementation, one or more chambers can also be configured downstream of the flocculation chamber 203, such as Figure 1 As shown, it can play a buffering role, preventing the formed flocs from being destroyed, and is also conducive to the continued flocculation reaction.

[0076] In practice, in order to facilitate the addition of coagulant into the coagulation chamber 202, the magnetic separation unit 200 further includes a PAC dosing device 204 for adding coagulant, such as Figure 1 As shown, the PAC dosing device 204 includes at least a container for preparing and / or storing a coagulant, a pipeline connecting the container with the coagulation chamber 202, and a PAC pump 209 configured in the pipeline. The PAC pump 209 can preferably be a metering pump to simultaneously meter the coagulant during delivery. Similarly, to facilitate the addition of flocculant to the flocculation chamber 203, the magnetic separation unit 200 also includes a PAM dosing device 206 for adding the flocculant. The PAM dosing device 206 includes at least a container for preparing and / or storing a coagulant, a pipeline connecting the container with the coagulation chamber 203, and a PAM pump 210 configured in the pipeline. The PAM pump 210 can preferably be a metering pump to simultaneously meter the flocculant during delivery, thereby accurately controlling the dosage.

[0077] The magnetic separation device 207 has multiple implementations. For example, the magnetic separation device 207 can adopt an existing super magnetic separator to separate the magnetic sludge in the wastewater by using the principle of magnetic adsorption. For another example, the magnetic separation device 207 can also adopt an existing magnetic sedimentation device to separate the magnetic sludge in the wastewater by using the principle of gravity sedimentation. However, both the super magnetic separator and the magnetic sedimentation device are provided with a sludge discharge end and a drainage end, wherein the sludge discharge end is used to discharge the separated magnetic sludge, and the drainage end is used to discharge the water body after the magnetic sludge is separated. As an example, in this embodiment, the magnetic separation device 207 can adopt an existing super magnetic separator, such as Figure 1 As shown, the supermagnetic separator includes a housing, a cavity constructed in the housing and used to accommodate wastewater, a number of magnetic disks disposed in the cavity, a sludge scraping mechanism adapted to each disk, a conveying trough adapted to the sludge scraping mechanism, a sludge discharge end (or sludge discharge port) connected to the conveying trough, and a motor. The housing is also constructed with a water inlet and a water outlet. Each disk is respectively disposed in the cavity and fixed to a rotating shaft. The rotating shaft is rotatably mounted on the housing and is in transmission connection with the motor. At the same time, the sludge scraping mechanism is also in transmission connection with the motor. The water inlet and water outlet are located on either side of the disk, and the magnetic coagulation reaction device 201 is connected to the water inlet. During actual operation, the conditioned wastewater enters the cavity through the water inlet and flows from the water inlet to the water outlet. The motor drives the magnetic disk to rotate and drives the sludge scraping mechanism to move synchronously, so that the magnetic flocs and other pollutants in the wastewater can be first adsorbed on the magnetic disk, and then scraped off from the water surface by the sludge scraping mechanism into the conveying trough to form magnetic sludge. The magnetic sludge is finally discharged from the super magnetic separator through the sludge discharge end, and the water body after the magnetic sludge is separated is discharged through the water outlet (i.e., the water outlet end), thereby achieving the purpose of purifying the wastewater.

[0078] Based on the magnetic separation wastewater system provided in this embodiment, the process of treating ammonia-nitrogen wastewater using the magnetic separation wastewater system adopts a magnetic composite material with ammonia-nitrogen adsorption function as a magnetic medium to realize the combination of adsorption and magnetic coagulation water treatment technology, such as Figure 1 、 Figure 6 and Figure 7 As shown, the specific steps include:

[0079] In step S1, a magnetic composite material with ammonia nitrogen adsorption function is used as a magnetic medium, and the magnetic medium and the wastewater are passed through each adsorption cavity 102 in turn, so that the magnetic medium and the wastewater are fully mixed in the adsorption reaction unit 100, so that mixing and adsorption of the dissolved ammonia nitrogen can be achieved during the passage, thereby achieving the purpose of effectively separating and removing soluble ammonia nitrogen from the wastewater. The soluble ammonia nitrogen is adsorbed in the magnetic medium, and the purpose of simultaneously removing the soluble ammonia nitrogen in the wastewater in the magnetic separation process can be achieved by separating the magnetic medium in the wastewater.

[0080] During implementation, the mixing time can be controlled by controlling parameters such as the wastewater delivery rate within the adsorption reaction chamber 101 and the dimensions of the adsorption reaction chamber 101. A shorter mixing time is not conducive to a full adsorption reaction, while a longer mixing time is detrimental to wastewater treatment efficiency. Preliminary experiments have shown that in step S1, the mixing time of the magnetic medium and wastewater within the adsorption reaction unit 100 can be 15-25 minutes. This ensures sufficient mixing and reaction between the magnetic medium and wastewater, while also maintaining adsorption and wastewater treatment efficiency.

[0081] In step S2, the wastewater after the adsorption reaction is continuously fed into the subsequent magnetic separation unit 200, and the wastewater is further treated using a magnetic separation process, so as to remove at least the insoluble pollutants in the wastewater using the magnetic separation process. Specifically, step S2 includes:

[0082] Step S2.1, adding an appropriate amount of reagent to the wastewater after mixing the magnetic medium in the magnetic coagulation reaction device 201, so as to form magnetic flocs in the wastewater through the magnetic coagulation reaction, which is convenient for the subsequent separation of magnetic sludge. Specifically, in this step, the added reagent can be a coagulant and / or a flocculant; for example, during implementation, a PAC dosing device 204 can be used to add an appropriate amount of PAC coagulant to the coagulation chamber 202, so as to use the PAC coagulant to change the surface properties of the colloids or suspended particles in the wastewater and promote their coagulation, and form magnetic flocs (or magnetic flocs). At the same time, a proper amount of PAM flocculant can be added to the flocculation chamber 203 through the PAM dosing device 206, so as to use the PAM flocculant to increase the aggregation of the magnetic flocs and obtain larger magnetic flocs, which is more conducive to the subsequent separation from the wastewater. It takes a certain amount of time for wastewater to pass through magnetic coagulation reaction device 201, which is the magnetic coagulation reaction time. In this process, the magnetic coagulation reaction time in magnetic coagulation reaction device 201 can be controlled within the range of 3-5 minutes. It has been verified that such a reaction time can achieve a better magnetic coagulation reaction effect, which is conducive to improving the subsequent removal rate of magnetic sludge, while also ensuring wastewater treatment efficiency. Since the adsorption and separation time are short throughout the entire process, it is beneficial to improve sewage treatment efficiency. It can achieve a better magnetic coagulation reaction effect while ensuring efficiency.

[0083] In step S2.2, the wastewater after the magnetic coagulation reaction is finally input into the magnetic separation device 207. The magnetic separation device 207 can use the magnetic field to absorb and separate the magnetic flocs in the wastewater. The magnetic flocs continuously separated from the magnetic separation device 207 gather together to form magnetic sludge. Since the ammonia nitrogen in the wastewater is adsorbed in the magnetic medium, and these magnetic media are contained in the magnetic sludge, the magnetic sludge separated from the wastewater is magnetic sludge containing ammonia nitrogen. These magnetic sludges are finally discharged through the mud discharge end of the magnetic separation device 207 so as to enter the subsequent regeneration circulation unit 300, and the water body after the magnetic flocs are separated is discharged through the drainage end of the magnetic separation device 207, realizing the separation of the magnetic flocs and the water body, thereby achieving the purpose of purifying the wastewater. This process adopts a magnetic composite material with ammonia nitrogen adsorption function as the magnetic medium, so that the magnetic medium can not only use the magnetic separation process in the magnetic separation unit 200 to remove suspended matter, TP insoluble COD and heavy metals and other insoluble pollutants in the wastewater, but also can undergo adsorption reaction with the wastewater in the adsorption reaction unit 100 to effectively remove the dissolved ammonia nitrogen in the wastewater, so that the process can remove dissolved ammonia nitrogen pollutants and insoluble pollutants in the wastewater at the same time through a one-time treatment process, which is conducive to achieving better wastewater treatment effects. In addition, in this process, since the dissolved ammonia nitrogen in the wastewater can be removed at the same time, the ammonia nitrogen content in the water body can be greatly reduced, and the removal effect of ammonia nitrogen can be enhanced, thereby significantly reducing the ammonia nitrogen content in the effluent, which is particularly suitable for treating wastewater rich in ammonia nitrogen.

[0084] It is understood that in this embodiment, the ammonia nitrogen refers to the combined nitrogen in the form of ammonia or ammonium ions, that is, the nitrogen in the form of free ammonia (NH3) and ammonium ions (NH4 + ) in the form of nitrogen. Since free ammonia and ammonium ions can be converted into each other, this embodiment can effectively remove ammonium ions, which means that this embodiment can effectively remove at least part of the free ammonia.

[0085] Example 2

[0086] In order to improve the economic efficiency of the above process and solve the problem of low-cost, high-efficiency reduction and regeneration of the above magnetic composite material, the main difference between this embodiment 2 and the above embodiment is that the magnetic separation wastewater system provided in this embodiment also includes a regeneration circulation unit 300 arranged downstream of the magnetic separation unit 200 and connected to the magnetic separation unit 200, such as Figure 2 and Figure 6As shown, the regeneration circulation unit 300 is specifically connected to the sludge discharge end of the magnetic separation equipment 207. The regeneration circulation unit 300 is mainly used to recover the magnetic material in the magnetic sludge, and to restore (or regenerate) and recover the magnetic medium from the recovered magnetic material, so that the magnetic medium regains the ability to adsorb ammonia nitrogen, so that the magnetic medium can be put back into the upstream adsorption reaction unit 100 to realize the recycling of the magnetic medium, thereby significantly improving the economy of this process.

[0087] Specifically, in this embodiment, the regeneration cycle unit 300 includes a primary magnetic recovery device 302, a regeneration agent dosing device 309 and a regeneration reactor 308, wherein Figure 2 As shown, the primary magnetic recovery device 302 is connected to the sludge discharge end of the magnetic separation device 207 to receive the separated magnetic sludge. The primary magnetic recovery device 302 can separate and recover the magnetic medium in the magnetic sludge through magnetic force (the magnetic medium includes the magnetic composite material after adsorbing ammonia nitrogen, and may also include a portion of the magnetic composite material without adsorbing ammonia nitrogen). During implementation, the primary magnetic recovery device 302 can adopt an existing magnetic recovery device, such as an existing disk-type magnetic separator or drum-type magnetic separator, to recover the magnetic medium in the magnetic sludge using the principle of magnetic adsorption. For example, the primary magnetic recovery device 302 includes a housing, a motor disposed in the housing, a magnetic drum, and a scraper mechanism adapted for the magnetic drum. The housing is constructed with a first cavity, and the magnetic drum is disposed in the first cavity. The motor is in transmission connection with the magnetic drum to drive the magnetic drum to rotate. The scraper mechanism is disposed on one side of the magnetic drum to scrape off the magnetic medium adsorbed on the magnetic drum. The scraped magnetic medium can be transported to the regeneration reactor 308 via a pipeline or a conveyor trough. At the same time, the shell of the primary magnetic recovery device 302 is configured with a first outlet, which is communicated with the first cavity and is used to discharge the separated sludge.

[0088] In this embodiment, the primary magnetic recovery device 302 is connected to the regeneration reactor 308 so that the separated magnetic material can be input into the regeneration reactor 308. For example, the primary magnetic recovery device 302 can be connected to the regeneration reactor 308 through the main conveying channel 304, channels, troughs and other components, so that the magnetic material separated from the primary magnetic recovery device 302 can enter the subsequent regeneration reactor 308. For example, a first temporary storage container 303 can be further configured between the primary magnetic recovery device 302 and the regeneration reactor 308. The primary magnetic recovery device 302 can be connected to the first temporary storage container 303 through pipes, channels, troughs and other components. The first temporary storage container 303 can be connected to the regeneration reactor 308 through the main conveying channel 304, channels, troughs and other components. When the main conveying channel 304 is used, the main conveying channel 304 is configured with a feed pump 306. The first temporary storage container 303 is used to temporarily store magnetic material and can cooperate with the feed pump 306 to input the magnetic material into the subsequent regeneration reactor 308 more smoothly and controllably. During implementation, the first temporary storage container 303 can be constructed as a separate component, or can be constructed in the housing of the primary magnetic recovery device 302, such as Figure 2 As shown, the first temporary storage container 303 and the primary magnetic recovery device 302 can be an integrated structure, and the first cavity and the first temporary storage container 303 are connected to each other. At this time, the first temporary storage container 303 can also be used to receive the scraped magnetic material. In addition, the first temporary storage container 303 can also be equipped with a stirrer 103, such as Figure 2 As shown, the stirrer 103 is used to stir the separated magnetic material.

[0089] In this embodiment, the regeneration reactor 308 is mainly used to provide a reaction site for the reaction between the regeneration agent and the magnetic medium (specifically, the magnetic medium after adsorbing ammonia nitrogen). For example, the regeneration reactor 308 is configured with a reaction chamber for providing a reaction site, such as Figure 2 As shown, the regeneration agent dosing device 309 and the first magnetic recovery device 302 (or the first temporary storage container 303) can be connected to the reaction chamber respectively. In implementation, the regeneration reactor 308 also includes a stirrer 103 configured in the reaction chamber, such as Figure 2 As shown, the stirrer 103 is used to make the regeneration agent and the magnetic composite material (magnetic medium) fully contact and react, ensuring that the recovered magnetic composite material has the ability to adsorb ammonia nitrogen again, which is beneficial to improving efficiency and effect.

[0090] In this embodiment, the regeneration agent dosing device 309 is connected to the regeneration reactor 308. Figure 2As shown, it is mainly used to add the required regenerant (regenerative agent) into the regeneration reactor 308. During implementation, the regenerant dosing device 309 includes a container for storing the regenerant and a dosing power 312. The container can be connected to the regeneration reactor 308 through a main dosing channel 310, a channel, etc. Figure 2 As shown, the dosing power 312 is used to provide power for the delivery of the regenerant, and the dosing power 312 can be a dosing pump, gravity difference, etc.

[0091] In a more perfect solution, the regeneration cycle unit 300 further includes a first deflocculant 301, which is disposed between the magnetic separation device 207 and the primary magnetic recovery device 302 and is connected to the magnetic separation device 207 and the primary magnetic recovery device 302, respectively. Figure 2 As shown, the first deflocculating machine 301 can adopt an existing high-speed deflocculating machine. For example, the first deflocculating machine 301 includes a shell, a deflocculating blade disc and a motor. The shell is constructed with a deflocculating chamber. The deflocculating blade disc is arranged in the deflocculating chamber and is connected to the motor transmission. In one embodiment, the deflocculating chamber of the first deflocculating machine 301 can be connected to the sludge discharge end of the magnetic separation device 207 through a pipeline, and can be connected to the first cavity of the primary magnetic recovery device 302 through a pipeline. The magnetic sludge can be broken up by the deflocculating blade disc in the deflocculating chamber, thereby achieving physical crushing, which is more conducive to the subsequent separation of the magnetic medium in the magnetic sludge, and is also conducive to improving the recovery rate of the magnetic medium in the magnetic sludge. In a further embodiment, as Figure 2 As shown, the first deflocculant 301 and the primary magnetic recovery device 302 can be an integrated structure. In this case, the deflocculant chamber of the first deflocculant 301 can be connected to the mud discharge end of the magnetic separation device 207 through a pipeline, and can be connected to the first cavity of the primary magnetic recovery device 302 through a connecting hole, which can also achieve the same effect. It will not be repeated here.

[0092] Based on the magnetic separation wastewater system provided in this embodiment, the process of treating ammonia-nitrogen-containing wastewater using the magnetic separation wastewater system further includes step S3, the recovery and regeneration of the magnetic medium, compared to the process of Example 1. Specifically, it can be that the regeneration circulation unit 300 is used to receive the magnetic sludge separated by the magnetic separation unit 200, and an appropriate amount of regeneration agent is added to the separated magnetic sludge, and the regeneration agent is used to exchange the ammonia-nitrogen ions adsorbed by the magnetic medium in the magnetic sludge to obtain a magnetic medium that does not contain ammonia-nitrogen. In this process, by configuring the regeneration circulation unit 300, the regeneration circulation unit 300 can be used to separate and restore the magnetic composite material from the magnetic sludge, so that the magnetic composite material regains the function of adsorbing ammonia-nitrogen, so as to facilitate the recovery and recycling of the magnetic medium, thereby significantly reducing operating costs and having better economic efficiency.

[0093] like Figure 2 and Figure 6As shown, during implementation, step S3 may specifically include the following steps:

[0094] In step S3.1, the magnetic sludge discharged from the sludge discharge port is physically crushed using the first deflocculant 301. The crushed magnetic sludge is then fed into the primary magnetic recovery device 302. Physically crushing the magnetic sludge first breaks up the magnetic flocs within the sludge, allowing for better separation of the magnetic medium from the sludge in the primary magnetic recovery device 302. This improves the recovery rate of the magnetic medium in the sludge and reduces the amount of residual magnetic medium in the sludge, thereby reducing operating costs and promoting energy conservation and environmental protection.

[0095] In step S3.2, the magnetic sludge separated by the magnetic separation unit 200 and broken up by the first deflocculant 301 is received by the primary magnetic recovery device 302, and the magnetic material is separated from the magnetic sludge by magnetic force. The separated magnetic material is input into the regeneration reactor 308 so as to restore and regenerate the magnetic medium in the regeneration reactor 308.

[0096] Step S3.3, using the regenerant dosing device 309 to add an appropriate amount of regenerant into the regeneration reactor 308, the regenerant containing sodium ions, for example, the regenerant can preferably use NaCl solution and / or NaOH solution, the regenerant and the magnetic substance are mixed and reacted in the regeneration reactor 308, so that the sodium ions in the regenerant are used to exchange the ammonia nitrogen ions adsorbed in the magnetic medium, thereby achieving the purpose of reducing the magnetic medium after the ammonia nitrogen adsorbed in the magnetic substance, so that the magnetic medium regains the ability to adsorb ammonia nitrogen, so that the magnetic medium can be reused and recycled. In addition, in this step, the amount of regenerant can be appropriately excessive to ensure that all magnetic media in the magnetic substance are reduced.

[0097] It is understandable that, during implementation, if the first deflocculant 301 and the first temporary storage container 303 are not provided in the magnetic separation wastewater system, there are no corresponding steps in the process, which will not be described in detail here.

[0098] During operation of the system, the adsorption reaction unit 100 and the magnetic separation unit 200 can operate continuously to continuously treat wastewater; the separated magnetic sludge can also be continuously fed into the primary magnetic recovery device 302 via the first deflocculant 301. The primary magnetic recovery device 302 can operate continuously and can continuously feed the separated magnetic material into the first temporary storage container 303. Since the reaction between the regenerant and the magnetic material in the reaction chamber of the regeneration reactor 308 requires a certain amount of time, the regeneration reactor 308 can only be operated intermittently during actual operation. That is, when the amount of magnetic material in the regeneration reactor 308 reaches a set threshold, the feed pump 306 stops feeding the magnetic material into the regeneration reactor 308. The timing of adding the regenerant can be determined according to actual needs. The required amount of regenerant can be added to the reaction chamber of the regeneration reactor 308 in one go before the magnetic material is added; the required amount of regenerant can also be added to the reaction chamber of the regeneration reactor 308 in one go after the magnetic material stops feeding; or the regenerant can be added to the reaction chamber simultaneously with the feeding of the magnetic material. The three addition timings can all be coordinated with the agitator 103 to allow the magnetic substance and the regeneration agent to fully contact and mix for a full reaction. Therefore, a certain amount of time needs to be reserved to allow the regeneration agent and the magnetic substance to fully react.

[0099] In addition, after the reaction is completed, the reaction mixture in the reaction chamber needs to be discharged. After the reaction chamber is emptied, one cycle ends, and then the magnetic material can continue to be transported into the reaction chamber. In this way, the magnetic medium can be regenerated in an intermittent manner. Therefore, the regeneration reactor 308 also includes a discharge mechanism adapted to the reaction chamber. The discharge mechanism is used to control whether to discharge the reaction mixture in the reaction chamber. The discharge mechanism has multiple implementation methods. For example, in one implementation, the discharge mechanism includes a discharge pipe and a discharge pump. The discharge pipe extends from the top of the reaction chamber to the bottom of the reaction chamber. The discharge pump is connected to the discharge pipe. When discharge is required, the discharge pump is turned on to extract the mixture in the reaction chamber, thereby achieving the purpose of emptying. In this embodiment, as Figure 2 As shown, the discharge mechanism includes a discharge channel 317 and a discharge on-off switch 318. The discharge channel 317 is arranged below the reaction chamber and communicates with the bottom of the reaction chamber. The discharge on-off switch 318 is used to control the on / off of the discharge channel 317. During implementation, the discharge channel 317 can be a pipe, a hole, etc., and the discharge on-off switch 318 can preferably be a valve, such as Figure 2 When discharge is required, the discharge switch 318 is turned on, and the mixture in the reaction chamber can be automatically discharged by gravity to achieve the purpose of emptying.

[0100] This intermittent process can be manually controlled or automatically controlled. To achieve automatic control, the system also includes a controller and a monitoring module for monitoring the amount of magnetic material in the reaction chamber. The controller is electrically connected to the feed pump 306 for controlling the start / stop of the feed pump 306 to control whether the magnetic material is transported into the reaction chamber. The monitoring module is electrically connected to the controller for monitoring whether the amount of magnetic material in the reaction chamber reaches a set threshold. The discharge mechanism is electrically connected to the controller (specifically, the discharge pump or the discharge switch 318 is electrically connected to the controller) for controlling whether the reaction mixture in the reaction chamber is discharged. During operation, when the monitoring module detects that the amount of magnetic material in the reaction chamber reaches the set threshold, the controller controls the feed pump 306 to shut down, thereby stopping the transportation of magnetic material into the reaction chamber.

[0101] The monitoring module can be implemented in various ways. For example, the monitoring module can be a flow meter, which can be located in the main delivery channel 304 to monitor the flow rate in the main delivery channel 304. The flow meter is electrically connected to a controller, which can calculate the amount of magnetic material in the reaction chamber based on the flow rate data fed back by the flow meter. Alternatively, the monitoring module can be a sensor located in the reaction chamber, with the controller electrically connected to the sensor. The sensor can preferably be a liquid level sensor to monitor the liquid level of the magnetic material in the reaction chamber. The controller can calculate the amount of magnetic material in the reaction chamber based on the liquid level fed back by the sensor. Of course, the sensor can also be a pressure sensor, and the monitoring module can also be a timer.

[0102] Of course, the controller can also be electrically connected to the stirrer 103 to control the start / stop of the stirrer 103 .

[0103] Based on this, the above process also includes a method for automatically regenerating the magnetic medium, including: initially, the discharge mechanism is in a closed state, the controller controls the feed pump 306 to start, so as to input the magnetic material into the reaction chamber, and during this process, the monitoring module is used to monitor the amount of the magnetic material in the reaction chamber; at the same time, the controller can control the regeneration agent dosing device 309 to synchronously add regeneration agent to the reaction chamber, and the controller controls the agitator 103 to start, so that the magnetic material and the regeneration agent fully contact and react;

[0104] When the monitoring module detects that the amount of magnetic material in the reaction chamber reaches a set threshold, the controller controls the feed pump 306 to be turned off and the dosing power 312 to be turned off; and records the duration of the dosing power 312 or the feed pump 306 being turned off, so as to reserve time for the reaction between the magnetic material and the regenerant, so that the regenerant and the magnetic material can fully react;

[0105] When the time reaches the set threshold, the controller can control the discharge mechanism to empty the reaction chamber, and finally the controller controls the discharge mechanism to close, completing the regeneration process of the magnetic medium. In this way, the magnetic medium can be automatically regenerated continuously in an intermittent manner.

[0106] During implementation, the controller may preferably use PLC and single chip microcomputer, or may use PC or embedded chip.

[0107] Example 3

[0108] After the reaction is completed, what is discharged from the regeneration reactor 308 is not pure magnetic medium, but a mixture. The mixture contains not only magnetic medium, but also the regeneration liquid after the reaction, the remaining regeneration agent, etc. If the mixture is directly transported to the adsorption reaction unit 100 for circulation, not only will new pollutants be introduced into the wastewater, but also the amount of magnetic medium added to the adsorption reaction unit 100 cannot be accurately controlled, which is not conducive to improving the water output effect. In order to solve this technical problem, the main difference between this embodiment 3 and the above-mentioned embodiment 2 is that in the magnetic separation wastewater system provided in this embodiment, the regeneration circulation unit 300 also includes a secondary magnetic recovery device 315, such as Figure 3 As shown, the secondary magnetic recovery device 315 is connected to the regeneration reactor 308. For example, the secondary magnetic recovery device 315 can be connected to the regeneration reactor 308 through a pipeline, a channel, etc. Figure 3 As shown, in this embodiment, the regeneration reactor 308 is connected to the regeneration reactor 308 through the discharge channel 317 in the discharge mechanism, and the secondary magnetic recovery device 315 mainly uses magnetic force to absorb the magnetic medium in the mixture;

[0109] like Figure 3 As shown, the secondary magnetic recovery device 315 can be connected to the adsorption reaction unit 100 through a reflux pipe 319. For example, the secondary magnetic recovery device 315 can be connected to the first-stage adsorption cavity 102 in the adsorption reaction unit 100, or it can be connected to the pipe upstream of the adsorption reaction box 101. The reflux pipe 319 is connected to a reflux pump 320. The reflux pump 320 is used to provide power for the reflux of the magnetic medium so as to transport the separated magnetic medium to the adsorption reaction unit 100 to achieve circulation, and the reflux amount of the magnetic medium can be accurately controlled by the reflux pump 320.

[0110] Similarly, during implementation, the secondary magnetic recovery device 315 can adopt an existing magnetic recovery device, such as an existing disk-type magnetic separator or a drum-type magnetic separator, so as to recover the magnetic medium in the mixture by using the principle of magnetic adsorption. The structure of the secondary magnetic recovery device 315 can be the same as that of the primary magnetic recovery device 302, for example, Figure 3As shown, the secondary magnetic recovery device 315 includes a shell, a motor arranged in the shell, a magnetic drum and a scraper mechanism adapted to the magnetic drum. A first cavity is constructed in the shell. During implementation, the first cavity is connected to the upstream regeneration reactor 308 to receive the mixture after the reaction. The magnetic drum is arranged in the first cavity, and the motor is connected to the magnetic drum for driving the magnetic drum to rotate. The scraper mechanism is arranged on one side of the magnetic drum for scraping off the magnetic medium adsorbed on the magnetic drum. The scraped magnetic medium can be transported to the adsorption reaction unit 100 through the reflux pipe 319. At the same time, the shell of the secondary magnetic recovery device 315 is also constructed with a first outlet, which is connected to the first cavity for discharging the mixed liquid after the magnetic medium is separated. Figure 3 As shown, such a design can realize the recycling of pure magnetic media to eliminate the influence of regeneration liquid, residual regeneration agent, etc., thereby effectively solving the above technical problems.

[0111] To facilitate the recycling of magnetic media, in a more complete solution, the regeneration cycle unit 300 also includes a second temporary storage container 316, which is connected to the secondary magnetic recovery device 315 and is used to receive and store the magnetic media separated from the secondary magnetic recovery device 315. The return pipe 319 can be connected to the second temporary storage container 316 to return the magnetic media in the second temporary storage container 316 to the adsorption reaction box 101. Similarly, during implementation, the second temporary storage container 316 can be constructed as a separate component or constructed in the shell of the secondary magnetic recovery device 315, such as Figure 3 As shown, the second temporary storage container 316 and the secondary magnetic recovery device 315 can be an integrated structure, and the second cavity and the second temporary storage container 316 are connected to each other. At this time, the second temporary storage container 316 can also be used to receive the magnetic medium scraped off by the scraper mechanism. In addition, the second temporary storage container 316 can also be equipped with a stirrer 103, such as Figure 3 As shown, the stirrer 103 is used to stir the magnetic medium evenly. During implementation, the stirrer 103 can adopt an existing stirrer 103, which will not be described in detail here.

[0112] In a more perfect solution, the regeneration circulation unit 300 further includes a second deflocculant 314. As shown in the figure, the second deflocculant 314 is disposed between the regeneration reactor 308 and the secondary magnetic recovery device 315, and is connected to the regeneration reactor 308 and the secondary magnetic recovery device 315, respectively. Figure 3As shown, the regeneration reactor 308 can be connected to the second deflocculator 314 through the discharge channel 317. The second deflocculator 314 can adopt an existing high-speed deflocculator. For example, the second deflocculator 314 includes a shell, a deflocculating blade disc and a motor. The shell is constructed with a deflocculating chamber. The deflocculating blade disc is arranged in the deflocculating chamber and is connected to the motor transmission. In one embodiment, the deflocculating chamber of the second deflocculator 314 can be connected to the regeneration reactor 308 through a pipeline to receive the mixture discharged from the regeneration reactor 308, and can be connected to the first cavity of the secondary magnetic recovery device 315 through a pipeline. The second deflocculator 314 is mainly used to break up the magnetic medium in the mixture to achieve physical crushing, which is more conducive to the subsequent better separation of the magnetic medium in the mixture and is also conducive to improving the recovery rate of the magnetic medium in the mixture. In a further embodiment, as Figure 3 As shown, the second deflocculant 314 and the secondary magnetic recovery device 315 can also be an integrated structure. In this case, the deflocculant chamber of the second deflocculant 314 can be connected to the regeneration reactor 308 through the discharge channel 317, and can be connected to the first cavity of the secondary magnetic recovery device 315 through the connecting hole, which can also achieve the same effect. It will not be repeated here.

[0113] Based on the magnetic separation wastewater system provided in this embodiment, the process of treating ammonia nitrogen-containing wastewater using the magnetic separation wastewater system is compared with Example 2, and step S3 further includes:

[0114] S3.4: The post-reaction mixture in the regeneration reactor 308 is first fed into the second deflocculator 314, where it is physically broken down. The broken mixture is then fed into the secondary magnetic recovery unit 315, where the magnetic field within the unit is then used to separate the magnetic medium from the mixture. In this process, physically breaking up the mixture first disperses the magnetic medium within the mixture, allowing for more thorough separation of the magnetic medium within the mixture in the secondary magnetic recovery unit 315. This significantly improves the recovery rate of the magnetic medium within the mixture and reduces the amount of residual magnetic medium in the mixture, which is beneficial for reducing operating costs and promoting energy conservation and environmental protection. Furthermore, the secondary magnetic recovery unit 315 can be configured to cooperate with the primary magnetic recovery unit 302, achieving two-stage magnetic recovery and avoiding the effects of excessive regeneration agent. This two-stage magnetic recovery process yields pure, adsorbent magnetic medium, enabling the recycling of magnetic composite materials with ammonia and nitrogen adsorption capabilities.

[0115] In addition, if Figure 7As shown, the process further includes step S4, adding the recovered magnetic medium to the adsorption reaction unit 100 to achieve circulation. The recovered magnetic medium can be transported by the reflux pump 320 and refluxed through the reflux pipe 319 to the adsorption reaction unit 100, thereby achieving the purpose of recycling and reusing the magnetic medium. As a result, the entire process can not only effectively remove ammonia nitrogen and insoluble pollutants from the wastewater, but also achieve the regeneration, recovery and recycling of the magnetic medium, thereby greatly reducing the application cost of the magnetic composite material with ammonia nitrogen adsorption function in this wastewater treatment process.

[0116] It is understandable that, during implementation, if the second deflocculant 314 and the second temporary storage container 316 are not provided in the magnetic separation wastewater system, there are no corresponding steps in the process, which will not be described in detail here.

[0117] Example 4

[0118] In order to solve the problem of improving process economy, the difference between this embodiment 5 and the above embodiments is that the magnetic separation wastewater system provided in this embodiment also includes a regeneration liquid treatment unit 400, and the regeneration liquid treatment unit 400 includes a crystallizer 402. The crystallizer 402 is connected to the first outlet of the secondary magnetic recovery device 315. The first outlet is used to output the mixed liquid after the magnetic medium is separated, such as Figure 4 and Figure 5 As shown, the mixed liquid after the magnetic medium is separated in the secondary magnetic recovery device 315 can enter the crystallizer 402 through the first outlet. During implementation, the crystallizer 402 can adopt the existing crystallizer 402.

[0119] In a more complete solution, the regeneration liquid processing unit 400 further includes a regeneration liquid collection tank 401 for temporarily storing the mixed liquid. The regeneration liquid collection tank 401 is arranged between the secondary magnetic recovery device 315 and the crystallizer 402. Figure 4 and Figure 5 As shown, the secondary magnetic recovery device 315 discharges the mixed liquid after separation of the magnetic medium into the regeneration liquid collection tank 401 through the first outlet, and the regeneration liquid collection tank 401 can input the mixed liquid into the crystallizer 402 through the delivery pump 321.

[0120] In addition, in a more complete solution, the magnetic separation wastewater system is further equipped with a sludge dewatering unit, which includes a sludge tank 501 and a sludge dewatering device 502. Figure 4 and Figure 5As shown, the first outlet of the primary magnetic recovery device 302 can be connected to the sludge tank 501 through a pipeline so that the non-magnetic sludge after separation of the magnetic material can be discharged into the sludge tank 501; the crystallizer 402 can also be connected to the sludge tank 501 through a pipeline to input the remaining liquid after separation of magnesium ammonium phosphate (MPA) precipitation into the sludge tank 501; at the same time, the sludge tank 501 can be connected to the sludge dewatering device 502 through a pipeline, and the pipeline is connected to a delivery pump 321. The sludge dewatering device 502 is used to dewater the sludge so as to achieve unified post-processing of the sludge. In implementation, the crystallizer 402 and the sludge dewatering device 502 can be implemented using existing technologies and will not be described here.

[0121] Based on the magnetic separation wastewater system provided in this embodiment, the process of treating ammonia nitrogen-containing wastewater using the magnetic separation wastewater system also includes step S5 compared to the process in Example 2, and post-treating the mixed liquid after the magnetic medium is separated in the secondary magnetic recovery device 315 to obtain magnesium ammonium phosphate compound fertilizer, so that the mixed liquid after the magnetic medium is separated in the secondary magnetic recovery device 315 can be fully utilized, thereby significantly improving the economic efficiency of this process.

[0122] Specifically, step S5 includes inputting the mixed liquid after the magnetic medium is separated in the secondary magnetic recovery device 315 into the crystallizer 402, such as Figure 6 and Figure 7 As shown,

[0123] At the same time, an appropriate amount of alkaline solution (such as NaOH), MgCl2 and NaH2PO4 are input into the crystallizer 402, so that the alkaline solution, MgCl2, NaH2PO4 and the mixed solution react chemically in the crystallizer 402 to generate magnesium ammonium phosphate (MPA).

[0124] Finally, the generated magnesium ammonium phosphate is separated by precipitation. The separated magnesium ammonium phosphate can be used as a compound fertilizer and has a certain economic value, so that the mixed liquid after the magnetic medium is separated in the secondary magnetic recovery device 315 can be fully utilized, thereby significantly improving the economic efficiency of the process.

[0125] To facilitate the addition of alkaline solution, MgCl2 and NaH2PO4, the regeneration liquid treatment unit 400 also includes a first container 403, a second container 404 and a third container 405. The first container 403, the second container 404 and the third container 405 can be connected to the crystallizer 402 through pipelines, and each pipeline is respectively equipped with a delivery pump 321. The first container 403, the second container 404 and the third container 405 are respectively used to prepare and store alkaline solution, MgCl2 and NaH2PO4, and the delivery pump 321 can preferably be a metering pump so that a fixed amount of alkaline solution, MgCl2 and NaH2PO4 can be delivered to the crystallizer 402 by the pump.

[0126] Example 5

[0127] Since the reaction between the regenerant and the magnetic material takes a certain amount of time, in order to further solve the problem of improving the regeneration efficiency, the main difference between this embodiment and the above embodiments is that the magnetic separation treatment system provided in this embodiment, the regeneration circulation unit 300 includes at least two reaction chambers, each reaction chamber can be arranged in parallel with each other, and each reaction chamber can be connected to the upstream primary magnetic recovery device 302 or the first temporary storage container 303, for example. Figure 5 As shown, each reaction chamber can be connected to the upstream first temporary storage container 303, and a regeneration agent dosing device 309 can be connected to each reaction chamber. The regeneration agent dosing device 309 can add regeneration agent to each reaction chamber. At the same time, each reaction chamber can be emptied separately, allowing each reaction chamber to be used sequentially and cyclically to continuously receive magnetic material from upstream without pausing, thereby continuously processing and regenerating magnetic media.

[0128] During implementation, the regeneration circulation unit 300 includes a regeneration reactor 308 , which is configured with at least two reaction chambers. Alternatively, the regeneration circulation unit 300 includes at least two regeneration reactors 308 , each of which is configured with a reaction chamber, as shown in the figure.

[0129] As an example, Figure 5 As shown, the primary magnetic recovery device 302 is directly or indirectly connected to the main conveying channel 304; for example, the main conveying channel 304 can be connected to the first temporary storage container 303, the main conveying channel 304 is connected to at least two sub-conveying channels 305, and a feed pump 306 is provided in the main conveying channel 304, each sub-conveying channel 305 is respectively connected to each reaction chamber, and each sub-conveying channel 305 is respectively provided with a feed switch 307, and a controller is electrically connected to each feed switch 307 for controlling the opening and closing of each feed switch 307. During operation, the controller can control the feed switch 307 so that each sub-conveying channel 305 is connected to the corresponding reaction chamber in sequence and in a cycle. In implementation, the feed switch 307 can be a valve, a gate, etc.

[0130] In order to facilitate the control of the amount of magnetic substance in the reactor, there are various implementation methods. For example, the monitoring module may include a flow meter arranged in the main conveying channel 304, which is electrically connected to the controller and is used to monitor the flow of the main conveying channel 304. The controller can calculate the amount of magnetic substance in the reaction chamber based on the opening time of the feed switch 307 corresponding to the reaction chamber and the flow data fed back by the flow meter; for example, the monitoring module may include a sensor arranged in each reaction chamber, and the controller is electrically connected to each sensor. The sensor may be a liquid level sensor for monitoring the liquid level height of the magnetic substance in each reaction chamber. The controller can calculate the amount of magnetic substance in the corresponding reaction chamber based on the liquid level height fed back by the sensor.

[0131] At the same time, if Figure 5 As shown, in the present embodiment, the container of the regenerant dosing device 309 is connected to the main dosing channel 310, the main dosing channel 310 is connected to at least two sub-dosing channels 311, and the dosing power 312 is arranged in the main dosing channel 310, each sub-dosing channel 311 is respectively connected to each reaction chamber, and each sub-dosing channel 311 is respectively provided with a dosing switch 313, and a controller is respectively electrically connected to each dosing switch 313 for controlling the on and off of each dosing switch 313. During operation, the controller can control the dosing switch 313 so that each sub-dosing channel 311 is connected to the corresponding reaction chamber in sequence and in a cycle. During implementation, the dosing switch 313 can adopt a valve, a gate, etc.

[0132] In order to facilitate the control of the dosage of the regenerant, there are various implementation methods. For example, the monitoring module can also include a flow meter arranged in the main dosage channel 310, and the flow meter is electrically connected to the controller for monitoring the amount of the added regenerant. For another example, the dosage power 312 itself can also adopt a metering pump to have a metering function.

[0133] like Figure 5 As shown, in this embodiment, each reaction chamber is equipped with a discharge mechanism, and the discharge channel 317 of the discharge mechanism is respectively connected to the corresponding reaction chamber. Each discharge channel 317 is provided with a discharge switch 318, and each discharge switch 318 is electrically connected to a controller, which is used to control the opening and closing of each discharge switch 318. The discharge channels 317 are respectively connected to the downstream secondary magnetic recovery device 315 or the second deflocculant 314.

[0134] In addition, the monitoring module can also be a timer, which is electrically connected to the controller so that timing control can be achieved through the timer. For example, when the feed switch 307 is turned on, the timer can start timing. When the preset time is reached, the amount of magnetic material in the reaction chamber just reaches a threshold. At this time, the controller can control the feed switch 307 to close and control another feed switch 307. In addition, the addition and discharge processes of the regeneration agent can also be controlled by timing, which will not be described in detail here.

[0135] Based on this, the above process also includes a method for continuously regenerating magnetic media, comprising:

[0136] Initially, all discharge switches 318 are in a closed state. The controller controls one of the feed switches 307 to be opened, while the other feed switches 307 are closed, so as to feed magnetic material into the reaction chamber corresponding to the feed switch 307 (for ease of description, it can be referred to as the first reaction chamber). During this process, the amount of magnetic medium in the reaction chamber is monitored. At the same time, the controller controls the dosing switch 313 corresponding to the reaction chamber to be opened, while the other dosing switches 313 are closed, so as to simultaneously add regenerant into the reaction chamber during the process of transporting the magnetic material, and the amount of regenerant added is monitored during this process.

[0137] When the controller detects that the amount of magnetic material in the reaction chamber reaches the set threshold, the controller turns off the feed switch 307 and the dosing switch 313 corresponding to the reaction chamber, and records the duration of the dosing switch 313 or the feed switch 307 being closed. At the same time, the controller synchronously controls the feed switch 307 and the dosing switch 313 corresponding to the next reaction chamber (for ease of description, it can be called the second reaction chamber) to open, so as to transport the magnetic material and the regeneration agent to the reaction chamber.

[0138] The controller controls the reaction time of the regeneration agent and the magnetic material in the reaction chamber through the said time length. When the said time length reaches the set threshold value, the controller controls the discharge switch 318 corresponding to the said reaction chamber (first reaction chamber) to open, and closes after emptying, completing the regeneration process of the magnetic medium.

[0139] Such a cycle enables each reaction chamber to take over the magnetic material in turn under the control of the controller and to perform the regeneration reaction of the magnetic medium in turn, thereby continuously realizing the regeneration of the magnetic medium and significantly improving the regeneration efficiency.

[0140] It is understandable that the controller can control the agitator 103 in the reaction chamber to turn on when the reactor starts to receive the magnetic material, and control the agitator 103 to turn off when the discharge switch 318 is closed.

[0141] Example 6

[0142] Studies have found that the above-mentioned magnetic composite material is sensitive to temperature, and temperature differences will seriously affect the saturated adsorption capacity and adsorption performance of the magnetic composite material. Therefore, in order to further solve the problem of improving the effective adsorption capacity and adsorption performance of the magnetic composite material, the magnetic separation wastewater system provided in this embodiment also includes a temperature control module, and the temperature control module includes a heating device and a temperature sensor. The heating device and the stabilization sensor are electrically connected to the controller respectively. The heating device is used to increase the temperature of the water body in the adsorption cavity 102 under the control of the controller, and the stabilization sensor is used to monitor the temperature data in the adsorption cavity 102 and transmit it to the controller. The controller controls the temperature in the adsorption cavity 102 within the set temperature range through the cooperation of the heating device and the temperature sensor, so that the magnetic medium and the waste water always complete the adsorption reaction within the temperature range, which can not only ensure that the magnetic composite material has good adsorption performance, but also improve the effective adsorption capacity of the magnetic composite material, which has the effect of further improving the adsorption performance.

[0143] Through experiments, it was found that when the temperature is in the range of 20℃ to 30℃, the magnetic composite material has a larger adsorption capacity and better adsorption performance. Therefore, in step S1 of the above process, the temperature in the adsorption cavity 102 can be controlled within the range of 20℃ to 30℃ by the temperature control module. At this temperature, not only can the magnetic medium be ensured to have better adsorption performance, but the effective adsorption capacity of the magnetic medium can also be increased, which has the effect of further improving the adsorption performance.

[0144] During implementation, the heating device can adopt an existing electric heating device, such as an electric heating wire or an electric heating rod, etc. The number of heating devices can be determined according to the number of adsorption cavities 102 and their own heating power, and one heating device or multiple heating devices can be set in the adsorption cavity 102.

[0145] The temperature sensor may be an existing temperature sensor, which may be disposed in the adsorption cavity 102 and fixed to the adsorption reaction box 101 .

[0146] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. A process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system, wherein the magnetic separation wastewater system comprises a magnetic separation unit, characterized in that: The magnetic separation wastewater system also includes an adsorption reaction unit, which includes an adsorption reaction box. The adsorption reaction box is equipped with an adsorption cavity, which is connected to the downstream magnetic separation unit. The process includes: Step S1, using a magnetic composite material with ammonia nitrogen adsorption function as a magnetic medium, inputting the magnetic medium and wastewater into an adsorption reaction unit, and achieving mixing of the magnetic medium and wastewater in the adsorption cavity and completing adsorption of dissolved ammonia nitrogen in the wastewater; the magnetic composite material includes a porous carrier with a chemical formula of Na2Al2Si2O8·nH2O and SmCo5 particles and Fe3O4 particles present in the pores of the porous carrier, wherein n ≥ 0, and the mass percentages of SmCo5:Fe3O4:carrier are 0.4-10%:30-50%:50-70%; and the pore diameters of the pores are 0.35-0.45 nm; In step S2, the wastewater is continuously fed into the magnetic separation unit and the wastewater is continuously treated using a magnetic separation process to at least remove insoluble pollutants in the wastewater.

2. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 1, characterized in that: The magnetic separation unit includes a magnetic coagulation reaction device and a magnetic separation device. The adsorption reaction unit is connected to the magnetic coagulation reaction device. The magnetic separation device is arranged downstream of the magnetic coagulation reaction device and is connected to the magnetic coagulation reaction device. The magnetic separation device includes a mud discharge end and a water discharge end. The magnetic separation process described in step S2 includes: S2.1, adding an appropriate amount of reagent to the wastewater after mixing with the magnetic medium in the magnetic coagulation reaction device, and forming magnetic flocs in the wastewater through magnetic coagulation reaction; S2.2, the magnetic separation equipment uses a magnetic field to separate the magnetic flocs in the wastewater to form magnetic sludge. The magnetic sludge is discharged through the sludge discharge end, and the water after the magnetic flocs are separated is discharged through the drainage end.

3. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 2, characterized in that: In step S1, the mixing time of the magnetic medium and the wastewater in the adsorption reaction unit is 15-25 minutes; and / or, in S2.1, the magnetic coagulation reaction time in the magnetic coagulation reaction device is 3-5 minutes; And / or, the adsorption reaction box is configured with at least two adsorption cavities connected in series, and the last adsorption cavity is connected to the magnetic separation unit; in the step S1, the wastewater and the magnetic medium are passed through each adsorption cavity in sequence, and mixing and completing the adsorption of ammonia nitrogen are achieved during the passage.

4. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 1, characterized in that: The magnetic separation wastewater system further includes a regeneration circulation unit disposed downstream of the magnetic separation unit and connected to the magnetic separation unit, and the process further includes: In step S3, a regeneration circulation unit is used to receive the magnetic sludge separated by the magnetic separation unit, and an appropriate amount of regeneration agent is added to the separated magnetic sludge to exchange the ammonia nitrogen ions adsorbed by the magnetic medium in the magnetic sludge with the regeneration agent to obtain a magnetic medium free of ammonia nitrogen.

5. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 4, characterized in that: The regeneration cycle unit includes a primary magnetic recovery device, a regenerant dosing device, and a regeneration reactor. The regeneration reactor is configured with a reaction chamber for providing a reaction site. The mud discharge end of the magnetic separation device is connected to the primary magnetic recovery device. The primary magnetic recovery device and the regenerant dosing device are respectively connected to the reaction chamber. Step S3 includes: S3.2, using a primary magnetic recovery device to separate magnetic material from the magnetic sludge, and inputting the separated magnetic material into the reaction chamber of the regeneration reactor; S3.3, use the regeneration agent dosing device to add an appropriate amount of regeneration agent into the reaction chamber of the regeneration reactor. The regeneration agent and the magnetic material are mixed and reacted in the reaction chamber to reduce the magnetic medium after the ammonia nitrogen is adsorbed in the magnetic material.

6. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 5, characterized in that: The regeneration cycle unit further includes a first deflocculator, which is respectively connected to the sludge discharge end of the magnetic separation device and the primary magnetic recovery device. Step S3 further includes, S3.1, physically crushing the magnetic sludge transported from the sludge discharge end using the first deflocculator, and feeding the physically crushed magnetic sludge into the primary magnetic recovery device; And / or, in S3.3, the regeneration agent contains sodium ions, and the sodium ions in the regeneration agent are used to exchange the ammonia nitrogen ions adsorbed in the magnetic medium.

7. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 5, characterized in that: The magnetic separation wastewater system further includes a controller and a monitoring module for monitoring the amount of magnetic material in the reaction chamber, and the regeneration reactor further includes a discharge mechanism adapted to the reaction chamber, wherein: The first-stage magnetic recovery device is connected to the main conveying channel, which is connected to the reaction chamber. The main conveying channel is equipped with a feed pump. The regeneration agent dosing device is connected to the reaction chamber through the main dosing channel, and the main dosing channel is equipped with a dosing power. The monitoring module, the discharge mechanism, the feed pump, and the dosing power are electrically connected to the controller, respectively. The process also includes a method for automatically regenerating the magnetic medium, including: initially, the discharge mechanism is in a closed state, the controller controls the feed pump to input magnetic material into the reaction chamber, and during this process, the monitoring module is used to monitor the amount of magnetic material in the reaction chamber; at the same time, the controller controls the regenerant dosing device to synchronously add regenerant to the reaction chamber, so that the magnetic material and the regenerant contact and react in the reaction chamber; When the monitoring module detects that the amount of magnetic material in the reaction chamber reaches the set threshold, the controller controls the feed pump and the dosing power to be turned off, and records the duration of the dosing power or feed pump being turned off, so as to reserve time for the reaction between the magnetic material and the regeneration agent; When the time reaches the set threshold, the controller controls the discharge mechanism to empty the reaction chamber, and finally controls the discharge mechanism to close, completing a regeneration process of the magnetic medium, and repeating the cycle.

8. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 5, characterized in that: The regeneration circulation unit also includes a secondary magnetic recovery device, which is connected to the regeneration reactor; the step S3 also includes, S3.4, inputting the mixture after the reaction in the regeneration reactor into the secondary magnetic recovery device, and using the magnetic field in the secondary magnetic recovery device to separate the magnetic medium in the mixture.

9. The process for treating ammonia-nitrogen-containing wastewater using a magnetic separation wastewater system according to claim 8, characterized in that: The regeneration circulation unit further includes a second deflocculator, which is respectively connected to the regeneration reactor and the secondary magnetic recovery device; S3.4 further includes the steps of inputting the mixture after the reaction in the regeneration reactor into the second deflocculator, physically crushing the mixture using the second deflocculator, and then inputting the physically crushed mixture into the secondary magnetic recovery device; And / or, the regeneration circulation unit also includes a second temporary storage container and a reflux pump, the second temporary storage container is connected to the secondary magnetic recovery device, and is used to receive and store the magnetic medium separated from the secondary magnetic recovery device, the second temporary storage container is connected to the adsorption reaction unit through a reflux pipe, and the reflux pump is connected to the reflux pipe to provide reflux power; the process also includes step S4, adding the obtained magnetic medium to the adsorption reaction unit to achieve circulation.

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