Electromagnetic alloy scale inhibitor and preparation method thereof

Abstract

The invention discloses an electromagnetic alloy scale inhibitor and a preparation method thereof, and relates to a scale inhibitor and a preparation method thereof. The invention discloses an electromagnetic alloy scale inhibitor. The component of the electromagnetic alloy scale inhibitor is CuZnNdFeB, the mass ratio of Cu to Zn to Nd to Fe to B in the CuZnNdFeB is (10 to 16) to (40 to 64) to (4 to 10) to (14 to 35) to (2 to 5). The CuZnNdFeB electromagnetic alloy scale inhibitor is prepared from CuZn powder and NdFeB powder, micro electricity and a micro magnetic field are formed by the CuZnNdFeB electromagnetic alloy scale inhibitor, Cu-Zn forms a battery which can receive ions such as calcium, magnesium and acid radicals dissolved in water, the ions are added into the arrangement of the battery, dipole groups are formed, and the dipole groups are large in size and poor in activity. And scale-forming ions or particles of calcium, magnesium and the like surrounded by the water dipole are not easy to contact with a metal heat exchange surface, so that the generation of scale is inhibited. Auxiliary equipment does not need to be added, so that the efficient scale inhibition effect is achieved.

Description

Technical Field

[0001] The invention relates to a scale inhibitor and a preparation method thereof. Background Art

[0002] Thermal power plants continue to play a crucial role in today's rapidly developing power industry. However, with growing energy demand and increasingly stringent environmental regulations, thermal power plants face unprecedented challenges in terms of operational efficiency and environmental performance. Problems with cooling water systems are particularly prominent. Deteriorating water quality is a primary concern. As water evaporates, salt concentrations increase, forming insoluble scale. This scale deposits on pipes and equipment, making it difficult to remove. This significantly reduces heat transfer efficiency and increases energy consumption.

[0003] Currently, the main method used to suppress scaling within the system is to add chemical scale inhibitors. Refractory polymers and the continuously added scale and corrosion inhibitors accumulate and concentrate within the system, leading to increased salinity in the circulating wastewater and excessive TOC. This not only deteriorates the effluent quality of the circulating wastewater regeneration system, making it difficult to meet the effluent requirements of the reclaimed water deep treatment system, but also increases the inlet load on the subsequent desalted water system and other water treatment systems. Therefore, there is an urgent need to systematically study and analyze the current problems with cooling circulating water and propose reasonable and effective solutions to effectively suppress scaling in the circulating cooling water system, ensure the efficient and stable operation of the entire system, and achieve the goals of saving water, reducing consumption, and increasing production capacity.

[0004] Chemical scale inhibition, commonly used in thermal power plants, is gradually being replaced by new green and environmentally friendly technologies. A variety of physical anti-scaling methods are currently being employed, including those utilizing electrical, magnetic, and acoustic fields. Because physical treatments require minimal or no chemical input, they are subject to fewer environmental and microbiological limitations than chemical treatments and offer significant potential and broad application prospects in water treatment. The following are the main existing physical anti-scaling methods.

[0005] Electric field scale inhibition: The principle is that under the action of a high-voltage electrostatic field, water dipoles are oriented and surround calcium, magnesium and other ions, inhibiting scale formation, and polarized water molecules can remove old scale. Studies have confirmed that electronic water processors have significant scale inhibition effects, with scale inhibition rates exceeding 96% in circulating cooling water systems and exceeding 94% in hot water systems. They also have a significant scale inhibition effect in water with high hardness. This technology is suitable for hot water systems, and its advantages lie in its high scale inhibition rate and scale removal function. However, it is limited by processing capacity, has high water quality requirements, and has high operating and maintenance costs. The scale removal effect is greatly affected by the nature of the scaling substances, and is not suitable for large-flow circulating cooling water systems.

[0006] Magnetic field scale inhibition: The principle is to use the magnetic field to affect the nucleation rate, crystal size, number and crystal form of scaling substances, such as promoting the transformation of calcite into aragonite. The magnetic treatment time, number of times and water flow rate affect the anti-scaling and descaling effect. Usually, a cyclic effect with a long residence time is effective, and there is an optimal flow rate. This technology is suitable for hot water boilers and heating systems, especially small heating systems with not too high water hardness. The advantage is that it can change the characteristics of scaling substances to achieve scale inhibition; the disadvantage is that the rust products in the system affect the effect. When used for descaling of large-capacity hot water boilers and heating networks, an iron removal device must be configured, which makes the system complicated and inconvenient to use.

[0007] Copper-zinc and multi-component alloy scale inhibition: Their scale inhibition mechanism is primarily based on redox reactions, electrochemical effects, and crystal structure regulation. Copper-zinc alloys use redox reactions to reduce the concentrations of residual chlorine, dissolved oxygen, and soluble heavy metal ions in water, altering the scale crystal structure, transforming calcite scale into aragonite scale, thereby reducing its adhesion to the heat exchanger wall. Simultaneously, changes in the redox potential of water at the contact interface inhibit microbial growth and reproduction, reducing the adhesion strength of scale to the heat exchanger wall. Multi-component alloys utilize the synergistic effects of multiple metals. For example, the addition of elements such as tin and nickel forms multi-component micro-batteries, which enhance the diversity of redox reactions, improve the alloy's stability, oxidation resistance, and corrosion resistance, further optimizing scale inhibition. Their advantages lie in their high efficiency, stability, long life, low cost, and environmental friendliness. Copper-zinc and multi-component alloy scale inhibition devices require no chemical agents, relying on physical and electrochemical effects to inhibit scale, reducing environmental pollution. They offer a long service life, 100% filtration capacity recovery, and reduced maintenance costs. They effectively remove a wide range of pollutants, improve water treatment efficiency, and maintain sustained high efficiency, all while requiring less energy. However, this technology also has its drawbacks. Under extreme high temperature and pressure, alloy materials are susceptible to intergranular corrosion. During the water purification process, agglomeration is prone to occur, affecting scale inhibition and service life. Furthermore, when recycled, heavy metals adsorbed on the surface of used alloy rods require specialized treatment to ensure an environmentally friendly closed-loop system. Summary of the Invention

[0008] In order to solve the technical problems existing in the above-mentioned physical anti-scaling, the present invention provides an electromagnetic alloy scale inhibitor and a preparation method thereof.

[0009] An electromagnetic alloy scale inhibitor, comprising CuZnNdFeB;

[0010] The mass ratio of Cu, Zn, Nd, Fe and B in the CuZnNdFeB is (10-16):(40-64):(4-10):(14-35):(2-5).

[0011] A method for preparing an electromagnetic alloy scale inhibitor is specifically completed by the following steps:

[0012] CuZn powder and NdFeB powder are uniformly mixed in a certain mass ratio, then ball-milled for a period of time under a hydrogen atmosphere, dehydrogenated at 600°C~800°C for a period of time, and finally maintained at a pressure of 10MPa~20MPa for a period of time under the condition of a magnetic field intensity of 10T to obtain a CuZnNdFeB electromagnetic alloy scale inhibitor.

[0013] Principle of the invention:

[0014] 1. The present invention uses CuZn powder and NdFeB powder to prepare a CuZnNdFeB electromagnetic alloy scale inhibitor, which forms a micro-electric + micro-magnetic field by itself. The Cu-Zn structure is a battery that can accept calcium, magnesium, acid radicals and other ions dissolved in water and add them to its arrangement to form dipole clusters. These dipole clusters are large in size and have poor mobility. Moreover, since the scale-forming ions or particles such as calcium and magnesium surrounded by the water dipoles are not easy to contact the metal heat exchange surface, the formation of scale is suppressed. After the hard water is treated with an electrostatic field, the polarized water molecules have strong permeability and solubility, which can gradually cause the scale that has been formed to crack, deform and fall off, not only preventing the formation of new scale, but also removing old scale. Similarly, the magnetic field generated by the NdFeB magnet can affect the nucleation rate, crystal size and number of scaling substances. When water passes through the magnetic field, the water molecules will be affected by the magnetic force, causing the electron cloud distribution inside them to change, thereby causing the water molecules to polarize. This polarization phenomenon causes water molecules to form an orderly arrangement and alters their original molecular structure, breaking them into smaller clusters. These smaller clusters have greater solubility and permeability, allowing them to more effectively surround and disperse mineral ions in the water, such as calcium and magnesium. Under the influence of a magnetic field, the surface charge and activity of these ions also change, reducing the chance of them binding and forming precipitation. Furthermore, the magnetic field may further reduce the binding forces between mineral ions by affecting the vibrational frequency and energy state of water molecules, thereby preventing scale formation. At high temperatures, aragonite is typically the first phase to precipitate from solution. However, aragonite is unstable and relatively loose, and it recrystallizes into calcite, forming a very compact shell. Magnetic treatment tends to promote the transformation of calcite into aragonite. Compared to existing high-voltage electric fields and applied magnetic fields, the micro-electric + micro-magnetic field composite, formed by constructing material components, effectively addresses the shortcomings of traditional chemical and physical scale inhibition methods, effectively suppressing scaling in circulating cooling water systems and ensuring efficient and stable operation of the entire system, thereby saving water, reducing energy consumption, and increasing production capacity.

[0015] Second, the CuZnNdFeB electromagnetic alloy scale inhibitor prepared by this invention has high water polarizability and large microcurrent, enabling it to prevent scale-forming ions from complexing in solution or disperse scale crystals in solution. The alloy components are highly magnetic, inducing crystal distortion to form larger, looser scale bodies that are easier to remove. Furthermore, the scale forms within the solution rather than adhering to the pipe surface, ensuring a sustained scale inhibition effect. Therefore, the electromagnetic alloy scale inhibitor can effectively prevent scale formation and deposition within circulating water systems.

[0016] Advantages of the present invention:

[0017] The present invention adds micro-magnetic field scale inhibition, abandoning the disadvantages of traditional magnetic field that requires the configuration of iron removal device, complex system, inconvenient application, etc.; the micro-electric + micro-magnetic field formed by the material does not require the addition of auxiliary equipment and can change the water performance by itself, thereby achieving a high-efficiency scale inhibition effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The XRD patterns of the CuZn powder and NdFeB powder obtained by ball milling for different times in Examples 1 to 4 are shown;

[0019] Figure 2 This is an SEM image of the powder obtained by ball milling CuZn powder and NdFeB powder for 20 hours in Example 4;

[0020] Figure 3 The XRD patterns of the powders obtained in Examples 5 to 7 after ball milling for 20 h and dehydrogenation at different temperatures are shown;

[0021] Figure 4 This is the SEM image of the powder obtained after ball milling for 20 hours and dehydrogenation at 800°C in Example 7;

[0022] Figure 5 This is a TEM image of the powder obtained after ball milling for 20 hours and then dehydrogenation at 800°C in Example 7;

[0023] Figure 6 This is a magnetic susceptibility analysis diagram of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Example 8;

[0024] Figure 7 Calcium and magnesium hardness of CuZn alloy and CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times;

[0025] Figure 8 The conductivity and microcurrent of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times;

[0026] Figure 9The total alkalinity diagram of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times;

[0027] Figure 10 The pH values ​​of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times. DETAILED DESCRIPTION

[0028] Specific embodiment 1: This embodiment is an electromagnetic alloy scale inhibitor, the composition of which is CuZnNdFeB;

[0029] The mass ratio of Cu, Zn, Nd, Fe and B in the CuZnNdFeB is (10-16):(40-64):(4-10):(14-35):(2-5).

[0030] Specific embodiment 2: This embodiment differs from specific embodiment 1 in that the preparation method of the electromagnetic alloy scale inhibitor is specifically completed according to the following steps:

[0031] CuZn powder and NdFeB powder are uniformly mixed in a certain mass ratio, ball-milled for a period of time under a hydrogen atmosphere, dehydrogenated for a period of time at 600°C to 800°C, and finally maintained at a pressure of 10 MPa to 20 MPa for a period of time under a magnetic field strength of 10 T to obtain a CuZnNdFeB electromagnetic alloy scale inhibitor. The remaining steps are the same as those in the first embodiment.

[0032] Specific embodiment 3: This embodiment differs from specific embodiment 1 or 2 in that the mass ratio of the CuZn powder to the NdFeB powder is (50-80):(20-50). The other steps are the same as specific embodiment 1 or 2.

[0033] Specific embodiment 4: This embodiment differs from specific embodiments 1 to 3 in that the mass ratio of the CuZn powder to the NdFeB powder is 80:20. The other steps are the same as those of specific embodiments 1 to 3.

[0034] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that the mass ratio of the CuZn powder to the NdFeB powder is 70:30. The other steps are the same as those of specific embodiments 1 to 4.

[0035] Specific embodiment 6: This embodiment differs from specific embodiments 1 to 5 in that the mass ratio of the CuZn powder to the NdFeB powder is 60:40. The other steps are the same as those of specific embodiments 1 to 5.

[0036] Specific embodiment 7: This embodiment differs from specific embodiments 1 to 6 in that the mass ratio of the CuZn powder to the NdFeB powder is 50:50. The other steps are the same as those of specific embodiments 1 to 6.

[0037] Specific embodiment 8: This embodiment differs from specific embodiments 1 to 7 in that the mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd to Fe to B in the NdFeB powder is 8:86:6. The other steps are the same as specific embodiments 1 to 7.

[0038] Specific embodiment 9: This embodiment differs from specific embodiments 1 to 8 in that the ball milling time is 10 to 20 hours and the pressure holding time is 0.2 hours. The other steps are the same as specific embodiments 1 to 8.

[0039] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that the dehydrogenation time is 0.5 h. The other steps are the same as those of specific embodiments 1 to 9.

[0040] The following examples are used to verify the beneficial effects of the present invention:

[0041] Example 1: CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio under hydrogen atmosphere, and their XRD test showed that Figure 1 As shown in the initial CuZn-NdFeB curve;

[0042] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0043] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0044] Example 2: CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio, and then ball-milled for 10 hours under hydrogen atmosphere. The XRD results showed that Figure 1 The CuZn-NdFeB was ball-milled for 10 h.

[0045] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0046] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0047] Example 3: CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio, and then ball-milled for 15 hours under hydrogen atmosphere. The XRD results showed that Figure 1 The CuZn-NdFeB was ball-milled for 15 h.

[0048] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0049] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0050] Example 4: CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio, and then ball-milled for 20 h in a hydrogen atmosphere. The XRD results showed that Figure 1 The CuZn-NdFeB was ball-milled for 20 h.

[0051] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0052] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0053] Figure 1 The XRD patterns of the CuZn powder and NdFeB powder obtained by ball milling for different times in Examples 1 to 4 are shown;

[0054] from Figure 1 It can be seen that as the ball milling time increases, NdFeB is hydrogenated and disproportionated, which leads to the refinement of CuZn alloy.

[0055] Figure 2 This is an SEM image of the powder obtained by ball milling CuZn powder and NdFeB powder for 20 hours in Example 4;

[0056] from Figure 2 It can be seen that after ball milling for 20 hours, the average particle diameter of the powder is 2μm.

[0057] Example 5: CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio, then ball-milled for 20 h in a hydrogen atmosphere, and then dehydrogenated at 700 ° C for 0.5 h. The XRD results showed that Figure 3 CuZn-NdFeB-700℃ dehydrogenation;

[0058] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0059] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0060] Example 6: CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio, then ball-milled for 20 h in a hydrogen atmosphere, and then dehydrogenated at 750 ° C for 0.5 h. The XRD results showed that Figure 3 CuZn-NdFeB-750℃ dehydrogenation;

[0061] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0062] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0063] Example 7: CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio, then ball-milled for 20 h in a hydrogen atmosphere, and then dehydrogenated at 800 ° C for 0.5 h. The XRD results showed that Figure 3 CuZn-NdFeB-800℃ dehydrogenation;

[0064] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0065] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0066] Figure 3 The XRD patterns of the powders obtained in Examples 5 to 7 after ball milling for 20 h and dehydrogenation at different temperatures are shown;

[0067] from Figure 3 It can be seen that after dehydrogenation and recombination at different temperatures, 800℃ has the best effect and can recombine into Nd2Fe14B.

[0068] Figure 4 This is the SEM image of the powder obtained after ball milling for 20 hours and dehydrogenation at 800°C in Example 7;

[0069] from Figure 4 It can be seen that after dehydrogenation and recombination, the powder particles still maintain at 2μm and do not grow.

[0070] Figure 5 This is a TEM image of the powder obtained after ball milling for 20 hours and then dehydrogenation at 800°C in Example 7;

[0071] Figure 5 TEM showed that the powder grain size was 7-9 nm.

[0072] Scale inhibition performance test:

[0073] (1) Scale inhibition performance: The static scale inhibition method was used to study the scale inhibition effect of electromagnetic alloy scale inhibitor on calcium carbonate and magnesium carbonate. The scale inhibition rate was used as the evaluation index to examine the effects of pH value, hardness ion concentration, temperature and action time on the scale inhibition performance of the alloy and determine the optimal position and distribution of the alloy. The specific test method is as follows:

[0074] Method for measuring particle size distribution: suspend the scale in deionized water to form a test solution (the concentration of the scale is 750 mg / L), place it in a sample tank, and use a laser diffraction particle size analyzer SALD-2300 to measure the particle size distribution and average particle size.

[0075] Scale composition analysis method: The same scale sample is divided into two parts, one of which is analyzed for inorganic components using XRD; the other scale is dissolved in hydrochloric acid, the organic components of the solution are extracted, and qualitative and quantitative analysis is performed using HPLC-MS and GC-MS.

[0076] Crystal structure research method: First, use a stereo optical microscope to select single crystals in the scale, then use an X-ray single crystal diffractometer to measure the single crystal to obtain the basic unit cell data (i.e. length, width and height), extract the XRD spectrum data of the scale, and then use DimondV4.1 software to simulate and analyze the crystal structure.

[0077] (2) Analysis of scale inhibition mechanism and effectiveness: According to the conventional salt content of the recycled water used by the Yundong Power Plant, a simulated water sample was prepared with a concentration ratio of 2.5, which was recorded as 0# water sample; on this basis, a simulated water sample with macromolecular organic matter was added, which was recorded as 1# water sample; using a dynamic small-scale experimental device, and taking the preferred electromagnetic alloy as the object, the influence of water quality factors and operating process parameters on its scale inhibition rate was investigated, and the data results of the scale inhibition performance research process were combined to establish the functional relationship between scale inhibition performance and alloy microstructure and operating process parameters, and to clarify the scale inhibition mechanism. Based on the alloy scale inhibition effectiveness analysis, the influence of alloys in different temperature fields on water quality and scale bodies was monitored to determine their effective scale inhibition time. The specific methods are as follows:

[0078] Oxidation potential and its interfacial reaction mechanism: Take two equal amounts of 0# water samples, one of which contains alloy and the other contains seed crystals (benchmark chemical CaCO3 is the seed crystal). The two water samples are subjected to dynamic small-scale experiments under exactly the same conditions to compare the kinetics of the two scaling processes. The redox potential, conductivity, Ca 2+ Concentration and alkalinity test, according to Ca 2+The scaling rate was calculated based on the concentration and alkalinity of the scale. Three scale samples were collected every 10 minutes using a syringe filter, one for particle size distribution analysis, one for calculating the scale accumulation per unit volume of liquid, and the final sample was dried. The dried scale was observed using a stereo optical microscope to determine the presence of single crystals and analyze the unit cell structure. The rate of change of the redox potential and the conductivity of the solution during the two scaling processes was compared to determine the microelectrical action stage of the alloy. The scaling rate, scale particle size distribution, and number of single crystals during the two scaling processes were compared to determine the nucleation stage. The scaling rate, scale accumulation, and crystal structure parameters during the two scaling processes were compared to determine the priority and synergy between the double-layer action and the nucleation action. Finally, the scaling process was simulated using Gussian software to verify the scientific validity of the redox potential, microelectric field, and segmented action of the scale during scaling, and to elucidate the redox potential effect and interfacial reaction mechanism. The scaling rate, scale particle size distribution, and number of single crystals during the two scaling processes were compared. The effects of the alloy on water quality and scale at different temperature fields were monitored to determine its effective scale inhibition time.

[0079] (3) Corrosion inhibition performance and corrosion inhibition mechanism: Under certain water quality factors and operating parameters, when the alloy is installed at different locations, monitor the redox potential, pH, coupon corrosion rate, etc. during operation. Based on the monitoring data obtained, analyze the wall effect according to the following methods; Based on the monitoring and analysis results, establish a functional relationship between corrosion inhibition performance and physical and chemical characteristics such as redox potential, interface mass transfer, and pH, and evaluate the scale inhibition and corrosion inhibition effect of the alloy and its mechanism of action. The test methods and calculation methods to be used in the research process are as follows:

[0080] Oxidation-reduction potential determination method: Take a clean 1000mL brown wide-mouth bottle and seal it tightly with a rubber stopper. Drill five holes in the stopper for inserting a platinum electrode, a calomel electrode, a thermometer, and two glass tubes (one for water inlet and one for water outlet). Place the water sample collected on-site into a plastic bucket and immediately seal it tightly. Drill a small hole in the bucket lid and insert a rubber tube into one of the holes. Siphon the water sample into the measurement bottle. While the water is flowing, measure the potential according to the instrument's operating instructions. The formula is as follows:

[0081] ;

[0082] Where E H : Redox potential of the water sample relative to the hydrogen standard electrode; Eo: Redox potential measured by the platinum electrode saturated calomel electrode; Er: Potential of the saturated calomel electrode relative to the hydrogen standard electrode.

[0083] pH determination method: immerse the electrode in a beaker containing the solution to be tested, gently shake the beaker to make the solution uniform, press the reading switch, the value indicated by the pointer is the pH value of the solution to be tested, repeat several times until the value remains unchanged (when the value of the digital pH meter changes by less than 0.01pH value in about 10s), it indicates that a stable reading has been reached.

[0084] Wall effect calculation method: According to the classical theory of metal electrochemical corrosion and based on Faraday's law, when current passes through an electrolyte solution, chemical changes will occur on the electrode, and the amount of chemical change is proportional to the amount of electricity passing through.

[0085] ;

[0086] Where: v is the corrosion rate of the metal, usually expressed as mass / time (such as g / h or mg / s) or thickness / time (such as μm / a); I is the corrosion current, that is, the current intensity that causes the metal to corrode, in amperes (A); n is the number of electrons transferred by the metal ion in the corrosion reaction; F is the Faraday constant, which is approximately 96485 C / mol and represents the charge per mole of electrons; A is the area of ​​the metal in square meters (m2). 2 ), typically the metal surface area exposed to the electrolyte solution.

[0087] Example 8: A method for preparing an electromagnetic alloy scale inhibitor is specifically completed according to the following steps:

[0088] CuZn powder and NdFeB powder were mixed uniformly in a certain mass ratio, then ball-milled in a hydrogen atmosphere for 20 hours, dehydrogenated at 800°C for 0.5 hours, and finally maintained at a pressure of 20 MPa for 0.2 hours under a magnetic field strength of 10 T to obtain a CuZnNdFeB electromagnetic alloy scale inhibitor.

[0089] The mass ratio of the CuZn powder to the NdFeB powder is 80:20;

[0090] The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:6.

[0091] Figure 6 This is a magnetic susceptibility analysis diagram of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Example 8;

[0092] from Figure 6Analysis of the room temperature hysteresis loop of the alloy powder shows that the hysteresis loop of the alloy is different from the typical hysteresis loop of the Nd-Fe-B alloy processed by conventional HDDR. This phenomenon is generally caused by the exchange coupling between the magnetic soft phase and the magnetic hard phase or the two sizes of grains in the same hard magnetic phase. Since the alloy powder prepared by the present invention presents a Nd2Fe14B / α-Fe two-phase microstructure, the grain size is basically uniform, about 30nm, and Figure 6 The kink shown occurs at a relatively low magnetic field of about 200 kA / m and may be related to the magnetization reversal of the nanoscale soft phase α-Fe in the alloy.

[0093] Example 9: This example differs from Example 8 in that the mass ratio of the CuZn powder to the NdFeB powder is 70:30. Other steps and parameters are the same as those in Example 8.

[0094] Example 10: This example differs from Example 8 in that the mass ratio of the CuZn powder to the NdFeB powder is 60:40. Other steps and parameters are the same as those in Example 8.

[0095] Example 11: This example differs from Example 8 in that the mass ratio of the CuZn powder to the NdFeB powder is 50:50. Other steps and parameters are the same as those in Example 8.

[0096] Application test 1: 4 portions (10 g) of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 were added to 4 portions (100 mL) of water with a scale concentration of 750 mg / L, respectively, and circulated for 0 h to 18 h by stirring with a peristaltic pump (the scale components are calcium carbonate and magnesium carbonate, wherein the molar ratio of calcium carbonate to magnesium carbonate is 1:1); then the calcium and magnesium hardness, conductivity, microcurrent, alkalinity and pH value at room temperature in the water were tested. Figure 7-10 As shown;

[0097] As a blank control, nothing was added to a portion of water with a scale concentration of 750 mg / L at room temperature. As a control, 10 g of CuZn alloy was added to 100 mL of water with a scale concentration of 750 mg / L and stirred and circulated for 0 h to 18 h using a peristaltic pump (the scale consisted of calcium carbonate and magnesium carbonate, with a molar ratio of calcium carbonate to magnesium carbonate of 1:1). The calcium and magnesium hardness of the water at room temperature was then tested. Figure 7 shown.

[0098] Application test 2: 4 portions (10 g) of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 were added to 4 portions of 100 mL of water at 70°C with a scale concentration of 750 mg / L, and the water was stirred and circulated for 0 h to 18 h by a peristaltic pump (the scale consisted of calcium carbonate and magnesium carbonate, with a molar ratio of calcium carbonate to magnesium carbonate of 1:1). The water was then tested for calcium-magnesium hardness at 70°C, electrical conductivity at 70°C, microcurrent at 70°C, total alkalinity at 70°C, and pH at 70°C. Figure 7-10 As shown;

[0099] As a blank control, no substance was added to a portion of water with a scale concentration of 750 mg / L at 70°C.

[0100] As a control, 10g of CuZn alloy was added to 100mL of water with a scale concentration of 750mg / L at 70℃ and circulated for 0h to 18h by a peristaltic pump (the scale consists of calcium carbonate and magnesium carbonate, with a molar ratio of calcium carbonate to magnesium carbonate of 1:1). The calcium and magnesium hardness of the water was then tested at 70℃. Figure 7 shown.

[0101] Figure 7 Calcium and magnesium hardness of CuZn alloy and CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times;

[0102] from Figure 7 It can be seen that the hardness of the circulating water treated with alloy decreases more slowly than that of the CuZn alloy and non-alloy water treatment tools. That is to say, the remaining calcium ions in the solution after alloy treatment are more than those in the solution without alloy treatment at the same circulation time, indicating that the amount of calcium ion scaling is reduced after alloy treatment; in addition, as the temperature rises to 70°C, the scale inhibition effect is consistent with that at room temperature, indicating that the water has a good scale inhibition effect after circulating and contacting the alloy.

[0103] Figure 8 The conductivity and microcurrent of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times;

[0104] from Figure 8 It can be seen that the conductivity and microcurrent of the circulating water treated with alloys decrease more slowly than those without alloy water treatment tools. That is to say, with the same circulation time, the free electrons released into the solution by the alloy are more than the calcium ions remaining in the solution without alloy water treatment. In addition, as the temperature rises to 70°C, the changes in current and conductivity are consistent with those at room temperature, indicating that the alloy releases electrons into the water, further enhancing the scale inhibition effect.

[0105] Figure 9The total alkalinity diagram of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times;

[0106] Depend on Figure 9 It can be analyzed that calcium bicarbonate continuously decomposes to form scale precipitation in the early stage, which continuously reduces the carbonate ions in the solution. According to the previous analysis, although the solubility of carbonate increases slightly, the loss of carbonate ions in scale formation is very small. Therefore, the total amount of alkaline ions in the solution decreases, causing the total alkalinity of the solution to decrease. The water treated with alloys increases the solubility of carbonate ions in the water due to the electrons dissolved in the alloy, which hinders their aggregation and nucleation. These effects make the ionic state in the water more, so the total alkalinity of the water treated with alloys is higher than that of untreated water. After heating for 8 hours, calcium bicarbonate completely decomposes and precipitates, and there is no bicarbonate in the solution. The water treated with alloys more quickly produces hydroxide ions, making the water weakly alkaline, and the total alkalinity increases rapidly compared to room temperature.

[0107] Figure 10 The pH values ​​of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8 to 11 in water at room temperature and 70°C at different times;

[0108] like Figure 10 As shown in the figure: the pH value of the circulating water increases with time. Generally speaking, the pH value of the water with alloy added is greater than that of the blank test. The pH value of the circulating water also increases with time. The higher the pH value of the water, the stronger its anti-corrosion ability.

Claims

1. An electromagnetic alloy scale inhibitor, characterized in that The electromagnetic alloy scale inhibitor is composed of CuZnNdFeB; The mass ratio of Cu, Zn, Nd, Fe and B in the CuZnNdFeB is (10-16):(40-64):(4-10):(14-35):(2-5).

2. The method for preparing an electromagnetic alloy scale inhibitor according to claim 1, characterized in that The preparation method of the electromagnetic alloy scale inhibitor is specifically completed according to the following steps: CuZn powder and NdFeB powder are uniformly mixed in a certain mass ratio, then ball-milled for a period of time under a hydrogen atmosphere, dehydrogenated at 600°C~800°C for a period of time, and finally maintained at a pressure of 10MPa~20MPa for a period of time under the condition of a magnetic field intensity of 10T to obtain a CuZnNdFeB electromagnetic alloy scale inhibitor.

3. The method for preparing an electromagnetic alloy scale inhibitor according to claim 2, characterized in that The mass ratio of the CuZn powder to the NdFeB powder is (50-80):(20-50).

4. The method for preparing an electromagnetic alloy scale inhibitor according to claim 3, characterized in that The mass ratio of the CuZn powder to the NdFeB powder is 80:

20.

5. The method for preparing an electromagnetic alloy scale inhibitor according to claim 3, characterized in that The mass ratio of the CuZn powder to the NdFeB powder is 70:

30.

6. The method for preparing an electromagnetic alloy scale inhibitor according to claim 3, characterized in that The mass ratio of the CuZn powder to the NdFeB powder is 60:

40.

7. The method for preparing an electromagnetic alloy scale inhibitor according to claim 3, characterized in that The mass ratio of the CuZn powder to the NdFeB powder is 50:

50.

8. The method for preparing an electromagnetic alloy scale inhibitor according to claim 2, characterized in that The mass ratio of Cu to Zn in the CuZn powder is 20:80; the mass ratio of Nd, Fe and B in the NdFeB powder is 8:86:

6.

9. The method for preparing an electromagnetic alloy scale inhibitor according to claim 2, characterized in that The ball milling time is 10h~20h; the pressure holding time is 0.2h.

10. The method for preparing an electromagnetic alloy scale inhibitor according to claim 2, characterized in that The dehydrogenation time is 0.5h.

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