Electromagnetic alloy scale inhibitor and preparation method thereof

Abstract

The application relates to an electromagnetic alloy scale inhibitor and a preparation method thereof. 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). The CuZnNdFeB electromagnetic alloy scale inhibitor is prepared from CuZn powder and NdFeB powder, microelectricity and a micro magnetic field are formed, the Cu-Zn battery can receive calcium, magnesium and acid radical ions dissolved in water to be arranged in the battery to form dipole groups, the volume of the dipole groups is large, and the activity is poor. In addition, the water dipoles are difficult to contact the metal heat exchange surface by surrounding the calcium, magnesium and other scale forming ions or particles, so that the scale formation is inhibited. The application does not need to increase auxiliary equipment, so that the high-efficiency scale inhibition effect is achieved.

Description

Technical Field

[0001] This invention relates to a scale inhibitor and its preparation method. Background Technology

[0002] In today's rapidly developing power industry, thermal power plants still play a crucial role. However, with the continuous growth of energy demand and increasingly stringent environmental requirements, the operational efficiency and environmental performance of thermal power plants face unprecedented challenges, especially in the cooling circulating water system, where problems are becoming increasingly prominent. Water quality deterioration is the primary issue. During the evaporation process, the salt concentration continuously increases, forming insoluble scale. This scale deposits on pipes and equipment and is difficult to remove, leading to a significant decrease in heat transfer efficiency and increased energy consumption.

[0003] Currently, the main method used is to add chemical scale inhibitors to suppress scaling within the system. However, the persistent high molecular weight polymers and the continuously added scale and corrosion inhibitors accumulate and concentrate within the system, leading to increased salinity and excessive TOC in the circulating wastewater. This not only deteriorates the effluent quality of the circulating wastewater reclaimed water treatment system, making it difficult to meet the requirements of the advanced greywater treatment system, but also increases the influent load on subsequent demineralized water systems and other water treatment systems. Therefore, it is urgent to conduct a systematic study and analysis of the current problems in cooling circulating water systems 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 water conservation, energy saving, and increased production capacity.

[0004] The chemical scale inhibition methods commonly used in thermal power plants are gradually being replaced by new green and environmentally friendly technologies. There are many physical scale inhibition methods, including those utilizing physical fields such as electricity, magnetism, and sound. Because physical treatments require little or no chemical reagents, they are less restricted by environmental and microbiological factors than chemical treatments, and therefore have great potential and broad application prospects in water treatment. The existing physical scale inhibition methods mainly include the following:

[0005] Electric field scale inhibition: Its principle is that under the action of a high-voltage electrostatic field, water dipoles align in a specific direction, surrounding calcium and magnesium ions, inhibiting scale formation, and polarized water molecules can remove old scale. Studies have confirmed that electronic water processors have a significant scale inhibition effect, with scale inhibition rates exceeding 96% in circulating cooling water systems and over 94% in hot water systems. It also shows significant scale inhibition in water with high hardness. This technology is suitable for hot water systems, with advantages including high scale inhibition rate and descaling function. However, it is limited by processing capacity, has high water quality requirements, high operation and maintenance costs, and its descaling effect is greatly affected by the properties of the scale deposits, making it unsuitable for high-flow-rate circulating cooling water systems.

[0006] Magnetic field scale inhibition: Its principle is to utilize a magnetic field to influence the nucleation rate, crystal size, number, and crystal form of scale-forming substances, such as promoting the transformation of calcite into aragonite. The magnetic treatment time, number of treatments, and water flow rate affect the scale prevention and removal effect. Generally, circulation and longer residence time result in better effects, and there is an optimal flow rate. This technology is suitable for hot water boilers and heating systems, especially small heating systems with relatively low water hardness. Its advantage lies in its ability to alter the characteristics of scale-forming substances to achieve scale inhibition; its disadvantage is that rust products in the system affect the effect, and when used for descaling large-capacity hot water boilers and heating networks, an iron removal device is required, leading to system complexity and inconvenience in application.

[0007] Copper-zinc and multi-element alloy scale inhibition: Their scale inhibition mechanism is mainly based on redox reactions, electrochemical effects, and crystal structure regulation. Copper-zinc alloys reduce the concentration of residual chlorine, dissolved oxygen, and soluble heavy metal ions in water through redox reactions, altering the scale crystal structure and transforming calcite-type scale into aragonite-type scale, thus reducing the adhesion to the heat exchange wall. Simultaneously, changes in the redox potential of the water at the contact interface inhibit microbial growth and reproduction, reducing the adhesion strength between the scale and the heat exchange wall. Multi-element alloys, through the synergistic effect of multiple metals, such as the addition of tin and nickel to form multi-element micro-batteries, enhance the diversification of redox reactions, improve alloy stability, oxidation resistance, and corrosion resistance, further optimizing the scale inhibition effect. Their advantages lie in high efficiency, stability, long lifespan, low cost, and environmental friendliness. Copper-zinc and multi-element alloy scale inhibition devices do not require the addition of chemical agents, relying on physical and electrochemical effects to achieve scale inhibition, reducing environmental pollution; they have a long service life, can restore 100% of their filtration capacity, reducing maintenance costs; they have good removal effects on various pollutants, and have advantages in improving water treatment efficiency and maintaining high efficiency continuously, with lower consumption. However, this technology also has its shortcomings. Under extreme high temperature and high pressure environments, alloy materials are prone to intergranular corrosion; during water purification, clumping is likely to occur, affecting scale inhibition and service life; in addition, when recycling waste alloy rods, the heavy metals adsorbed on the surface require professional treatment to ensure an environmentally friendly closed loop. Summary of the Invention

[0008] To address the technical problems associated with physical scale prevention, this invention provides an electromagnetic alloy scale inhibitor and its preparation method.

[0009] An electromagnetic alloy scale inhibitor, the composition of which is CuZnNdFeB;

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

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

[0012] CuZn powder and NdFeB powder are mixed evenly at a certain mass ratio, then ball-milled for a period of time under a hydrogen atmosphere, then dehydrogenated at 600℃~800℃ for a period of time, and finally held under a pressure of 10MPa~20MPa for a period of time under a magnetic field strength of 10T to obtain CuZnNdFeB electromagnetic alloy scale inhibitor.

[0013] Principle of this invention:

[0014] I. This invention utilizes CuZn powder and NdFeB powder to prepare a CuZnNdFeB electromagnetic alloy scale inhibitor. It generates a micro-electricity and micro-magnetic field, where the Cu-Zn structure acts as a battery, attracting dissolved calcium, magnesium, and acid anions from water to form dipole clusters. These dipole clusters are relatively large and have poor mobility. Furthermore, because the scale-forming ions or particles surrounded by these water dipoles are less likely to contact the metal heat exchange surface, scale formation is inhibited. After electrostatic treatment, the polarized water molecules exhibit strong permeability and solubility, gradually causing existing scale to crack, deform, and detach. This not only prevents new scale formation but also removes old scale. Similarly, the magnetic field generated by the NdFeB magnet affects the nucleation rate, crystal size, and number of scale-forming substances. When water passes through the magnetic field, water molecules are subjected to magnetic force, causing changes in their internal electron cloud distribution, leading to polarization. This polarization phenomenon promotes the orderly arrangement of water molecules and alters their original molecular cluster structure, causing them to break down into smaller water molecule clusters. These smaller water molecule clusters have stronger solubility and permeability, and can more effectively surround and disperse mineral ions in the water, such as calcium and magnesium. Under the influence of the magnetic field, the surface charge and activity of these ions also change, reducing their chance of combining to form precipitation. In addition, the magnetic field may further reduce the binding force between mineral ions by affecting the vibrational frequency and energy state of water molecules, thereby preventing scale formation. At high temperatures, aragonite is usually the first phase precipitated from the solution, but aragonite is unstable and relatively loose, and will recrystallize into calcite to form a very dense shell. Magnetic treatment tends to promote the transformation of calcite into aragonite. Compared with existing high-voltage electric fields and external magnetic fields, by constructing a micro-electric + micro-magnetic field composite material, the shortcomings of traditional chemical and physical scale inhibition can be effectively solved, effectively inhibiting scale formation in circulating cooling water systems, ensuring the efficient and stable operation of the entire system, and achieving the goals of water saving, energy saving, and increased production capacity.

[0015] II. The CuZnNdFeB electromagnetic alloy scale inhibitor prepared in this invention has the characteristics of high water polarizability and large microcurrent, which enables it to prevent the complexation of scale-forming ions in the solution or disperse the scale microcrystals in the solution. The alloy components have high magnetic properties, which can induce crystal distortion and form larger and looser scale, which is easy to remove. Furthermore, the scale forms in the solution rather than adhering to the pipe surface, thus continuously exerting its scale inhibition effect. Therefore, the electromagnetic alloy scale inhibitor can effectively prevent the formation and deposition of scale inside the circulating water system.

[0016] Advantages of this invention:

[0017] This invention incorporates a micro-magnetic field for scale inhibition, eliminating the disadvantages of traditional magnetic fields that require iron removal devices, have complex systems, and are inconvenient to apply. The micro-electricity and micro-magnetic field formed by the material can change the properties of the water itself without the need for additional auxiliary equipment, thereby achieving a highly efficient scale inhibition effect. Attached Figure Description

[0018] Figure 1 The images show the XRD patterns of CuZn powder and NdFeB powder obtained by ball milling for different times in Examples 1-4.

[0019] Figure 2 This is a 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 after ball milling for 20 hours and dehydrogenation at different temperatures in Examples 5-7 are shown.

[0021] Figure 4 This is a 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 dehydrogenation at 800°C in Example 7.

[0023] Figure 6 The magnetic susceptibility analysis diagram of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Example 8 is shown.

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

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

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

[0027] Figure 10 The pH values ​​of the CuZnNdFeB electromagnetic alloy scale inhibitors prepared in Examples 8-11 at different times in water at room temperature and 70°C. Detailed Implementation

[0028] Specific Implementation Method 1: This implementation method is an electromagnetic alloy scale inhibitor with the composition CuZnNdFeB;

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

[0030] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One 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 mixed evenly at a certain mass ratio, then ball-milled for a period of time under a hydrogen atmosphere, followed by dehydrogenation at 600℃~800℃ for a period of time, and finally held at a pressure of 10MPa~20MPa for a period of time under a magnetic field strength of 10T to obtain CuZnNdFeB electromagnetic alloy scale inhibitor. Other steps are the same as in specific implementation method one.

[0032] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the mass ratio of CuZn powder to NdFeB powder is (50~80):(20~50). The other steps are the same as in Specific Implementation Method One or Two.

[0033] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the mass ratio of CuZn powder to NdFeB powder is 80:20. The other steps are the same as in Specific Implementation Methods One to Three.

[0034] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the mass ratio of CuZn powder to NdFeB powder is 70:30. The other steps are the same as in Specific Implementation Methods One to Four.

[0035] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the mass ratio of CuZn powder to NdFeB powder is 60:40. The other steps are the same as in Specific Implementation Methods One to Five.

[0036] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One through Six in that the mass ratio of CuZn powder to NdFeB powder is 50:50. The other steps are the same as in Specific Implementation Methods One through Six.

[0037] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One to Seven in that the mass ratio of Cu to Zn in the CuZn powder is 20:80; and the mass ratio of Nd, Fe, and B in the NdFeB powder is 8:86:6. The other steps are the same as in Specific Implementation Methods One to Seven.

[0038] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that the ball milling time is 10-20 hours, and the holding time is 0.2 hours. The other steps are the same as in Specific Implementation Methods One to Eight.

[0039] Specific Implementation Method Ten: The difference between this implementation method and Specific Implementation Methods One to Nine is that the dehydrogenation time is 0.5 hours. The other steps are the same as in Specific Implementation Methods One to Nine.

[0040] The beneficial effects of the present invention are verified using the following embodiments:

[0041] Example 1: CuZn powder and NdFeB powder were mixed uniformly at a certain mass ratio under a hydrogen atmosphere, and their XRD was tested. (See figure) Figure 1 The initial CuZn-NdFeB curve is shown in the figure.

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

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

[0044] Example 2: CuZn powder and NdFeB powder were mixed evenly at a certain mass ratio, and then ball-milled for 10 hours under a hydrogen atmosphere. The XRD pattern was then tested. (See figure). Figure 1 As shown in the figure, CuZn-NdFeB was ball-milled for 10 hours.

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

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

[0047] Example 3: CuZn powder and NdFeB powder were mixed evenly at a certain mass ratio, and then ball-milled for 15 hours under a hydrogen atmosphere. The XRD pattern was then tested. (See figure). Figure 1 As shown in the figure, CuZn-NdFeB was ball-milled for 15 hours.

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

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

[0050] Example 4: CuZn powder and NdFeB powder were mixed evenly at a certain mass ratio, and then ball-milled for 20 hours under a hydrogen atmosphere. The XRD pattern was then tested. (See figure). Figure 1 As shown in the figure, CuZn-NdFeB was ball-milled for 20 hours.

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

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

[0053] Figure 1 The images show the XRD patterns of CuZn powder and NdFeB powder obtained by ball milling for different times in Examples 1-4.

[0054] from Figure 1 It can be seen that as the ball milling time increases, NdFeB undergoes hydrogen disproportionation, leading to the refinement of the CuZn alloy.

[0055] Figure 2 This is a 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 at a certain mass ratio, then ball-milled for 20 hours under a hydrogen atmosphere, and then dehydrogenated at 700℃ for 0.5 hours. The XRD pattern was then tested. (See figure) Figure 3 CuZn-NdFeB dehydrogenation at 700℃;

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

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

[0060] Example 6: CuZn powder and NdFeB powder were mixed uniformly at a certain mass ratio, then ball-milled for 20 hours under a hydrogen atmosphere, and then dehydrogenated at 750°C for 0.5 hours. The XRD pattern was then tested. (See figure). Figure 3 CuZn-NdFeB dehydrogenation at 750℃;

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

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

[0063] Example 7: CuZn powder and NdFeB powder were mixed uniformly at a certain mass ratio, then ball-milled for 20 hours under a hydrogen atmosphere, and then dehydrogenated at 800℃ for 0.5 hours. The XRD pattern was then tested. (See figure) Figure 3 CuZn-NdFeB dehydrogenation at 800℃;

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

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

[0066] Figure 3 The XRD patterns of the powders obtained after ball milling for 20 hours and dehydrogenation at different temperatures in Examples 5-7 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 to form Nd2Fe14B.

[0068] Figure 4 This is a 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 remain 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 dehydrogenation at 800°C in Example 7.

[0071] Figure 5 TEM results show that the powder grain size is 7-9 nm.

[0072] Scale inhibition performance test:

[0073] (1) Scale inhibition performance: The scale inhibition effect of the electromagnetic alloy scale inhibitor on calcium carbonate and magnesium carbonate was studied using the static scale inhibition method. The scale inhibition rate was used as the evaluation index. The effects of pH value, hardness ion concentration, temperature, and reaction time on the scale inhibition performance of the alloy were investigated to determine the optimal location and distribution of the scale inhibitor. Specific test methods are as follows:

[0074] Method for determining particle size distribution: The scale is suspended in deionized water to form the test solution (the concentration of scale is 750 mg / L), which is then placed in the sample cell and measured using a SALD-2300 laser diffractometer to obtain the particle size distribution and average particle size.

[0075] Scale composition analysis method: The same scale sample was divided into two parts. One part was analyzed for inorganic components by XRD. The other part of the scale was dissolved in hydrochloric acid, and the organic components of the solution were extracted and analyzed qualitatively and quantitatively by HPLC-MS and GC-MS.

[0076] Crystal structure research method: First, a stereomicroscope is used to select single crystals in the scale. Then, an X-ray single crystal diffractometer is used to measure the single crystals to obtain the basic data of the unit cell (i.e., length, width and height). The XRD pattern data of the scale is extracted. Then, the crystal structure is analyzed by simulation using Diamond V4.1 software.

[0077] (2) Scale inhibition mechanism and time-dependent analysis: Based on the conventional salinity of the reclaimed water used in Yundong Power Plant, a simulated water sample was prepared with a concentration ratio of 2.5, designated as sample 0#. A simulated water sample with added macromolecular organic matter was designated as sample 1#. Using a dynamic small-scale experimental setup and focusing on the selected electromagnetic alloy, the influence of water quality factors and operating process parameters on the scale inhibition rate was investigated. Combined with the data results from the scale inhibition performance study, a functional relationship between scale inhibition performance and alloy microstructure and operating process parameters was established to elucidate the scale inhibition mechanism. Based on the alloy scale inhibition time-dependent analysis, the influence of alloys at different temperature fields on water quality and scale was monitored to determine their effective scale inhibition time. Specific methods are as follows:

[0078] Oxidation potential and its interfacial reaction mechanism: Two equal volumes of water sample #0 were taken. One sample was placed with an alloy, and the other was treated with seed crystals (CaCO3, the reference chemical, was used as the seed crystals). Dynamic small-scale experiments were conducted on both samples under identical conditions to compare the kinetics of the two scaling processes. Oxidation-reduction potential, conductivity, and CaCO3 were measured every 5 minutes. 2+ Concentration and alkalinity tests, based on Ca 2+The scaling rate was calculated based on concentration and alkalinity. Three samples of scale were collected every 10 minutes using a needle filter; one sample was used for particle size distribution testing, one for calculating the amount of scale formed per unit volume of liquid, and the last sample was dried. The presence of single crystals in the dried scale was observed using a stereomicroscope, and the cell structure was analyzed. The rate of change of redox potential and solution conductivity during the two scaling processes was compared to determine the micro-electrical interaction 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 priority and synergy of double-layer action and nucleation action were determined by comparing the scaling rate, scale amount, and crystal structure parameters during the two scaling processes. Finally, the scaling process was simulated using Gussian software to assess the scientific validity of redox potential, micro-electric field, and segmented nucleation action during scaling; the effect of redox potential and its interfacial reaction mechanism were elucidated. The scaling rate, scale particle size distribution, and number of single crystals during the two scaling processes were compared, and the effects of the alloy at different temperature fields on water quality and scale were monitored to determine its effective scale inhibition time.

[0079] (3) Corrosion Inhibition Performance and Mechanism: Under certain water quality factors and operating parameters, when the alloy installation location is different from the distribution, the redox potential, pH, and corrosion rate of the coated plates are monitored during operation. Based on the obtained monitoring data, the wall effect is analyzed according to the following methods. Based on the monitoring and analysis results, the functional relationship between corrosion inhibition performance and the physicochemical properties of redox potential, interfacial mass transfer, and pH is established to evaluate the scale inhibition and corrosion inhibition effects of the alloy and its mechanism of action. The testing and calculation methods to be used in the study are as follows:

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

[0081] ;

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

[0083] pH measurement 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, and the value indicated by the pointer is the pH value of the solution to be tested. Repeat several times until the value remains unchanged (for digital pH meters, the value changes by less than 0.01 pH value within about 10 seconds), indicating that a stable reading has been reached.

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

[0085] ;

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

[0087] Example 8: A method for preparing an electromagnetic alloy scale inhibitor, specifically comprising the following steps:

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

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

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

[0091] Figure 6 The magnetic susceptibility analysis diagram of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Example 8 is shown.

[0092] from Figure 6Room temperature hysteresis loop analysis of the alloy powder revealed a kink in its hysteresis loop, unlike the typical hysteresis loop of Nd-Fe-B alloys processed by conventional HDDR. This phenomenon is generally caused by exchange coupling between the soft and hard magnetic phases or by two different grain sizes within the same hard magnetic phase. The alloy powder prepared in this invention exhibits a two-phase microstructure of Nd2Fe14B / α-Fe with a relatively uniform grain size of approximately 30 nm. Figure 6 The kink shown occurs under a relatively low magnetic field, approximately 200 kA / m, and this kink may be related to the magnetization reversal of the nanoscale soft phase α-Fe in the alloy.

[0093] Example 9: The difference between this example and Example 8 is that the mass ratio of CuZn powder to NdFeB powder is 70:30. All other steps and parameters are the same as in Example 8.

[0094] Example 10: The difference between this example and Example 8 is that the mass ratio of CuZn powder to NdFeB powder is 60:40. All other steps and parameters are the same as in Example 8.

[0095] Example 11: The difference between this example and Example 8 is that the mass ratio of CuZn powder to NdFeB powder is 50:50. All other steps and parameters are the same as in Example 8.

[0096] Application Experiment 1: Four 10g portions of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8-11 were added to four 100mL portions of water with a scale concentration of 750mg / L. The mixture was circulated using a peristaltic pump for 0-18 hours with stirring. (The scale consisted of calcium carbonate and magnesium carbonate, with a molar ratio of 1:1.) The room temperature calcium and magnesium hardness, room temperature conductivity, room temperature microcurrent, room temperature total alkalinity, and room temperature pH were then tested. See [see details]. Figures 7-10 As shown;

[0097] As a blank control, no substance was added to a sample 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 the mixture was circulated using a peristaltic pump for 0-18 hours with stirring (the scale consisted of calcium carbonate and magnesium carbonate, with a molar ratio of 1:1). The calcium and magnesium hardness of the water at room temperature was then tested. Figure 7 As shown.

[0098] Application Experiment 2: Four 10g portions of the CuZnNdFeB electromagnetic alloy scale inhibitor prepared in Examples 8-11 were added to four 100mL portions of water at 70℃ with a scale concentration of 750mg / L. The mixture was circulated using a peristaltic pump for 0-18 hours (the scale consisted of calcium carbonate and magnesium carbonate, with a molar ratio of 1:1). The calcium and magnesium hardness, conductivity, microcurrent, total alkalinity, and pH of the water at 70℃ were then tested. See [see details]. Figures 7-10 As shown;

[0099] As a blank control, no substances were added to a sample 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 using a peristaltic pump for 0h~18h with stirring (the scale consisted of calcium carbonate and magnesium carbonate, with a molar ratio of 1:1); then the calcium and magnesium hardness of the water at 70℃ was tested, see [reference needed]. Figure 7 As shown.

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

[0102] from Figure 7 It can be seen that the hardness of the circulating water treated with alloy decreases more slowly than that treated with CuZn alloy and without alloy. In other words, after the same circulation time, there are more calcium ions remaining in the alloy-treated solution than in the untreated solution, indicating that the amount of calcium scale formed after alloy treatment is less. In addition, as the temperature rises to 70℃, the scale inhibition effect is the same as 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 8-11 in water at different times at room temperature and 70°C.

[0104] from Figure 8 It can be seen that the conductivity and microcurrent of the circulating water treated with alloy decrease more slowly than those of the water treatment tool without alloy. In other words, for 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 treatment. In addition, as the temperature rises to 70℃, the changes in current and conductivity are consistent with those at room temperature, indicating that the release of electrons into the water by the alloy further enhances the scale inhibition effect.

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

[0106] Depend on Figure 9 Analysis shows that in the early stages, calcium bicarbonate continuously decomposes to form scale precipitate, which reduces the amount of carbonate ions in the solution. Although the solubility of carbonates increases slightly as previously analyzed, this increase is negligible compared to the loss of carbonate ions due to scale formation. Therefore, the total amount of alkaline ions in the solution decreases, leading to a reduction in the total alkalinity. In water treated with the alloy, the electrons dissolved from the alloy increase the solubility of carbonate ions, hindering their aggregation and nucleation. These effects result in a higher ionic state in the water, hence the total alkalinity of alloy-treated water is higher than that of untreated water. After heating for 8 hours, calcium bicarbonate completely decomposes and precipitates, eliminating bicarbonate ions from the solution. The alloy-treated water then rapidly 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 inhibitors prepared in Examples 8-11 at different times in water at room temperature and 70°C.

[0108] like Figure 10 As shown: the pH value of circulating water increases over time. Overall, the pH value of water with added alloy is generally higher than that of the blank test. The pH value of circulating water also generally increases over time, and the higher the pH value of the water, the stronger its corrosion resistance.

Claims

1. A method for preparing an electromagnetic alloy scale inhibitor, characterized in that... The preparation method of the electromagnetic alloy scale inhibitor is specifically carried out according to the following steps: CuZn powder and NdFeB powder are mixed evenly at a certain mass ratio, then ball-milled for a period of time under a hydrogen atmosphere, then dehydrogenated at 600℃~800℃ for a period of time, and finally held under a pressure of 10MPa~20MPa for a period of time under a magnetic field strength of 10T to obtain CuZnNdFeB electromagnetic alloy scale inhibitor.

2. The method for preparing an electromagnetic alloy scale inhibitor according to claim 1, characterized in that... The mass ratio of CuZn powder to NdFeB powder is (50~80):(20~50).

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

20.

4. The method for preparing an electromagnetic alloy scale inhibitor according to claim 2, characterized in that... The mass ratio of CuZn powder to NdFeB powder is 70:

30.

5. The method for preparing an electromagnetic alloy scale inhibitor according to claim 2, characterized in that... The mass ratio of CuZn powder to NdFeB powder is 60:

40.

6. The method for preparing an electromagnetic alloy scale inhibitor according to claim 2, characterized in that... The mass ratio of CuZn powder to NdFeB powder is 50:

50.

7. The method for preparing an electromagnetic alloy scale inhibitor according to claim 1, characterized in that... The CuZn powder has a Cu to Zn mass ratio of 20:80; the NdFeB powder has a Nd, Fe, and B mass ratio of 8:86:

6.

8. The method for preparing an electromagnetic alloy scale inhibitor according to claim 1, characterized in that... The ball milling time is 10-20 hours; the pressure holding time is 0.2 hours.

9. The method for preparing an electromagnetic alloy scale inhibitor according to claim 1, characterized in that... The dehydrogenation time is 0.5 h.

10. An electromagnetic alloy scale inhibitor prepared by the preparation method according to any one of claims 1 to 9.

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