Method for preparing arsenic adsorbent from aluminum electrolysis red mud, application and purification device

Abstract

The invention provides a method for preparing an arsenic adsorbent from aluminum electrolysis red mud, application and a purification device. The method for preparing the arsenic adsorbent from the aluminum electrolysis red mud comprises the following steps: S1, selecting the aluminum electrolysis red mud, crushing the aluminum electrolysis red mud by a crusher, sieving the crushed aluminum electrolysis red mud by a 100-200-mesh sieve, and drying the sieved aluminum electrolysis red mud to obtain dried red mud powder; s2, the dried red mud and sodium hydroxide are weighed and mixed for 2-3 h in a planetary ball mill according to the proportion of 1: (1-1.5), deionized water is added into the mixture after mixing, and slurry is prepared; and S3, the slurry is subjected to an alkali fusion reaction for 1.5-3 h at the temperature of 350 DEG C, hematite is converted into maghemite, and porous sintered structure ore containing active iron sites is formed. According to the method for preparing the arsenic adsorbent from the aluminum electrolysis red mud, the phase conversion path of iron in the red mud is regulated and controlled through the alkali fusion temperature gradient, high-selectivity synthesis of maghemite is achieved, meanwhile, the water leaching purification and in-situ activation integrated design is adopted, the specific surface area and the surface active site density of the adsorbent are synchronously increased, and therefore the arsenic adsorbent is prepared. The high-value utilization of the red mud is realized.

Description

Technical Field

[0001] This invention relates to the field of arsenic adsorbent preparation, and more particularly to a method, application, and purification device for preparing arsenic adsorbents from aluminum electrolysis red mud. Background Technology

[0002] Red mud is an industrial waste produced during the alkaline extraction of aluminum from bauxite. Its main components are oxides of iron, aluminum, and titanium, as well as silicates. It is characterized by fine particles, strong alkalinity, and large yields. Globally, over 100 million tons of red mud are produced annually. Its large-scale stockpiling not only occupies land but also poses a serious threat to the ecological environment due to its high pH level and the migration of harmful components.

[0003] Among them, the research on using the rich iron oxides in red mud (such as Fe2O3 content often exceeding 50%) to prepare adsorbents for removing arsenic pollutants in water has attracted much attention. However, traditional industrial red mud has a small specific surface area, few active sites, low adsorption capacity, and contains a large number of desilication products and calcium compounds, which can easily lead to an increase in solution pH and affect the adsorption effect.

[0004] Existing red mud activation methods include acid treatment, thermal treatment, and carbonization, but these methods suffer from problems such as complex processes, high costs, secondary pollution, and room for improvement in the specific surface area and surface active site density of the adsorbent. For example, acid treatment consumes large amounts of strong acid and generates wastewater containing heavy metals; high-temperature roasting is energy-intensive and can easily lead to the transformation of iron oxide crystals, reducing adsorption activity. Therefore, developing a simple, efficient, and environmentally friendly red mud treatment process to prepare arsenic adsorbents with high specific surface area and magnetic properties is of great significance for the resource utilization of red mud and the treatment of arsenic-containing wastewater.

[0005] Therefore, it is necessary to provide a method for preparing arsenic adsorbents from aluminum electrolytic red mud to solve the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides a method for preparing arsenic adsorbents from aluminum electrolytic red mud, which solves the problem that there is still room for improvement in the specific surface area and surface active site density of the adsorbent.

[0007] To solve the above-mentioned technical problems, the present invention provides a method for preparing arsenic adsorbent from aluminum electrolysis red mud, comprising the following steps:

[0008] S1. Select aluminum electrolysis red mud, crush it with a crusher, pass it through a 100-200 mesh sieve, and then dry it to obtain dry red mud powder;

[0009] S2. Weigh the dried red mud and sodium hydroxide and mix them in a planetary ball mill at a ratio of 1:(1~1.5) for 2~3 hours. After mixing, add deionized water to the mixture to make a slurry.

[0010] S3. The slurry is subjected to an alkaline fusion reaction at 350℃ for 1.5~3h to transform hematite into magnetite, forming a porous sintered structure mineral with active iron sites.

[0011] S4. Crush the porous sintered ore, pass it through a 100-200 mesh sieve, mix it with deionized water at a solid-liquid ratio of 1:(3-5), place it in a water bath and react at 70-80℃ for 45-90 minutes, then filter to separate the filter residue and leachate.

[0012] S5. Wash the filter residue with hot water at 60~80℃ in a solid-liquid ratio of 1:(7~10) until neutral. Place the washed powder in an oven and dry it at 80~90℃ for 12 hours to obtain an arsenic adsorbent with a porous structure and magnetic response.

[0013] This invention also provides an application of an arsenic adsorbent, wherein the arsenic adsorbent prepared using the method for preparing arsenic adsorbent from aluminum electrolysis red mud includes the following steps:

[0014] S01. Arsenic-containing wastewater is sequentially filtered through a bar screen, settled in a sedimentation tank, and filtered through a sand filter to remove suspended solids before being introduced into the purification device.

[0015] S02. Add an adjusting agent to the arsenic-containing wastewater to adjust the pH of the wastewater to 5.0~8.0;

[0016] S03. Add arsenic adsorbent to arsenic-containing wastewater, stir for a preset time, and let stand for 10-20 minutes.

[0017] S04. The treated wastewater is discharged and the arsenic adsorbent enriched with arsenic is separated by magnetic attraction. The wastewater after magnetic attraction enters the next treatment step.

[0018] S05. The arsenic-enriched adsorbent and eluent are mixed at a solid-liquid ratio of 1:(10~20), stirred for 60~120 min, washed with deionized water until neutral after elution, and dried to obtain the regenerated arsenic adsorbent.

[0019] The present invention also provides a purification device for the application of the arsenic adsorbent, comprising: a support;

[0020] A purification box, comprising a box body, a box cover, and a discharge square tube, wherein the box body is mounted on the bracket, the box cover is mounted on the top of the box body, the discharge square tube is disposed on one side of the bottom of the box body, and a valve is provided on the discharge square tube;

[0021] A stirring device is installed on the tank cover, and the stirring end extends into the interior of the tank.

[0022] A lifting device is used to lift the lid of the box.

[0023] A magnetic attraction structure, comprising a guide box and an electromagnet, wherein the guide box is inclinedly suspended below the discharge square tube, and the electromagnet is installed inside the guide box.

[0024] Compared with related technologies, the method for preparing arsenic adsorbent from aluminum electrolysis red mud provided by the present invention has the following beneficial effects:

[0025] This invention provides a method for preparing arsenic adsorbents from aluminum electrolysis red mud. By controlling the phase transformation path of iron in red mud through alkali melting temperature gradient, a highly selective synthesis of maghemite is achieved. At the same time, an integrated design of water leaching purification and in-situ activation is adopted to simultaneously improve the specific surface area and surface active site density of the adsorbent, realize the high-value utilization of red mud, significantly improve arsenic adsorption performance, and combine environmental benefits with economic benefits.

[0026] Through coordinated control of process parameters, the entire process does not require the addition of external iron sources or magnetic materials. Based on the composition of red mud itself, it achieves the integration of "adsorption-magnetic separation" dual functions, realizing the high-value transformation of red mud from "solid waste" to "magnetic adsorption material". It provides an innovative solution for the disposal of solid waste and the treatment of heavy metal pollution in the aluminum industry, breaks through the traditional red mud adsorption performance bottleneck, and has significant industrial application value. Attached Figure Description

[0027] Figure 1 A flowchart illustrating the steps of the method for preparing arsenic adsorbent from aluminum electrolytic red mud provided by the present invention;

[0028] Figure 2 This is a flowchart illustrating the steps involved in applying the arsenic adsorbent provided by the present invention.

[0029] Figure 3 This is a schematic diagram of the purification device provided by the present invention;

[0030] Figure 4 for Figure 3 A structural schematic diagram from another perspective is shown;

[0031] Figure 5 for Figure 3 A partial cross-sectional view of the purification device shown;

[0032] Figure 6 This is a schematic diagram showing the assembly of the drive head and the square shaft, where... Figure 6 (a) is Figure 5 An enlarged schematic diagram of section A shows the drive head and square shaft separated. Figure 6 (b) is a schematic diagram showing the assembly state of the drive head and the square shaft;

[0033] Figure 7 A schematic diagram of the rotating component, the feeding device, and the magnetic suction structure provided by the present invention;

[0034] Figure 8 This is a schematic diagram of the structure of the feeding device provided by the present invention;

[0035] Figure 9 This is a schematic diagram showing the state of the drive shaft being inserted into the insertion hole, as provided by the present invention.

[0036] Figure 10 A schematic diagram showing the working state of the feeding device provided by the present invention;

[0037] Figure 11 A schematic diagram of the assembly of the limiting shaft structure and the insertion hole provided by the present invention;

[0038] Figure 12 This is a schematic diagram of the positioning structure provided by the present invention.

[0039] Numbering on the map:

[0040] 1. Bracket;

[0041] 2. Purification box; 21. Box body; 22. Box cover; 23. Discharge square pipe; 231. Valve; 211. Liquid inlet pipe;

[0042] 3. Stirring device; 31. Motor; 32. Stirring shaft; 33. Stirring blades; 34. Drive head; 341. Square groove; 342. Circular cavity; 343. Drive shaft;

[0043] 4. Lifting device; 41. Lifting cylinder; 42. Connecting plate; 43. Positioning rod;

[0044] 5. Magnetic suction structure; 51. Guide box; 52. Electromagnet; 53. Slide base;

[0045] 6. Rotating component; 61. Rotating shaft; 62. Connecting arm; 63. Square shaft;

[0046] 7. Feeding device; 71. Driving component; 72. Sliding frame; 73. Push plate;

[0047] 711. Drive tube; 712. Winding wheel; 713. First pull rope; 714. Second pull rope;

[0048] 701. Socket; 702. Guide wheel assembly; 721. Guide wheel;

[0049] 8. Liquid container; 9. Collection box; 10. Support;

[0050] 20. Limiting shaft structure;

[0051] 30. Positioning structure; 301. L-shaped frame; 302. U-shaped frame; 303. Second spring. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0053] This invention provides a method for preparing arsenic adsorbents from aluminum electrolytic red mud.

[0054] Please refer to the following: Figure 1 In one embodiment of the present invention, the method for preparing arsenic adsorbent from aluminum electrolysis red mud includes the following steps:

[0055] S1. Select aluminum electrolysis red mud, crush it with a crusher, pass it through a 100-200 mesh sieve, and then dry it to obtain dry red mud powder;

[0056] S2. Weigh the dried red mud and sodium hydroxide and mix them in a planetary ball mill at a ratio of 1:(1~1.5) for 2~3 hours. After mixing, add deionized water to the mixture to make a slurry.

[0057] S3. The slurry is subjected to an alkaline fusion reaction at 350℃ for 1.5~3h to transform hematite into magnetite, forming a porous sintered structure mineral with active iron sites.

[0058] S4. Crush the porous sintered ore, pass it through a 100-200 mesh sieve, mix it with deionized water at a solid-liquid ratio of 1:(3-5), place it in a water bath and react at 70-80℃ for 45-90 minutes, then filter to separate the filter residue and leachate.

[0059] S5. Wash the filter residue with hot water at 60~80℃ in a solid-liquid ratio of 1:(7~10) until neutral. Place the washed powder in an oven and dry it at 80~90℃ for 12 hours to obtain an arsenic adsorbent with a porous structure and magnetic response.

[0060] The method for preparing arsenic adsorbents from aluminum electrolysis red mud provided by this invention achieves highly selective synthesis of maghemite by controlling the phase transformation pathway of iron in red mud through an alkali fusion temperature gradient. Simultaneously, it employs an integrated design of water leaching purification and in-situ activation to simultaneously increase the specific surface area and surface active site density of the adsorbent, enabling high-value utilization of red mud, significantly improving arsenic adsorption performance, and combining environmental benefits with economic viability.

[0061] Through coordinated control of process parameters, the entire process does not require the addition of external iron sources or magnetic materials. Based on the composition of red mud itself, it achieves the integration of "adsorption-magnetic separation" dual functions, realizing the high-value transformation of red mud from "solid waste" to "magnetic adsorption material". It provides an innovative solution for the disposal of solid waste and the treatment of heavy metal pollution in the aluminum industry, breaks through the traditional red mud adsorption performance bottleneck, and has significant industrial application value.

[0062] As an embodiment of the present invention, it specifically includes:

[0063] Example 1

[0064] S1. Select aluminum electrolysis red mud, crush it with a jaw crusher and pass it through a 150-mesh sieve. Control the particle size of the powder to ensure that the particle size is within a certain range. Place it in a 100℃ oven to dry for 12 hours to remove moisture and volatile impurities, and obtain dried red mud powder.

[0065] S2. Weigh 20g of dried red mud and sodium hydroxide and mix them in a planetary ball mill at a mass ratio of 1:1 for 2 hours. After thorough mixing, add 10ml of deionized water to the mixture to make a uniform slurry.

[0066] S3. Place the prepared slurry in a crucible and put it into a muffle furnace. Perform an alkaline fusion reaction at 350°C for 1.5 hours to promote the transformation of hematite into magnetite and form a porous sintered mineral rich in active iron sites.

[0067] S4. Crush the sintered ore with an agate mortar and sieve it through a 150-mesh sieve. Then, mix the sieved powder with deionized water in a solid-liquid ratio of 1:4 and place it in a water bath. React at 70°C for 45 minutes. Filter to separate the residue and leachate. The leachate can be used to recover sodium aluminate.

[0068] S5. Wash the filter residue repeatedly with hot water at a solid-liquid ratio of 1:7 until neutral to remove residual alkali and impurity ions. Place the washed powder in an oven and dry it at 80°C for 12 hours to prevent the phase transformation of iron oxide and hydroxide, and finally obtain an arsenic adsorbent with a porous structure and high magnetic response.

[0069] Example 2

[0070] S1. Select aluminum electrolysis red mud, crush it with a jaw crusher and pass it through a 200-mesh sieve. Control the particle size of the powder to ensure that the particle size is within a certain range. Place it in a 100℃ oven to dry for 12 hours to remove moisture and volatile impurities, and obtain dried red mud powder.

[0071] S2. Weigh 50g of dried red mud and sodium hydroxide and mix them in a planetary ball mill at a mass ratio of 1:1.25 for 3 hours. After thorough mixing, add 20ml of deionized water to the mixture to make a uniform slurry.

[0072] S3. Place the prepared slurry in a crucible and put it into a muffle furnace. Perform an alkaline fusion reaction at 450℃ for 2.5 hours to promote the transformation of hematite into magnetite and form a porous sintered mineral rich in active iron sites.

[0073] S4. Crush the sintered ore with an agate mortar and sieve it through a 200-mesh sieve. Then, mix the sieved powder with deionized water in a solid-liquid ratio of 1:5 and place it in a water bath. React at 75°C for 60 minutes. Filter to separate the residue and leachate. The leachate can be used to recover sodium aluminate.

[0074] S5. Wash the filter residue repeatedly with hot water at a solid-liquid ratio of 1:9 until neutral to remove residual alkali and impurity ions. Place the washed powder in an oven and dry it at 85°C for 12 hours to prevent the phase transformation of iron oxide and hydroxide, and finally obtain an arsenic adsorbent with a porous structure and high magnetic response.

[0075] Example 3

[0076] S1. Select aluminum electrolysis red mud, crush it with a jaw crusher and pass it through a 100-mesh sieve. Control the particle size of the powder to ensure that the particle size is within a certain range. Place it in a 100℃ oven to dry for 12 hours to remove moisture and volatile impurities, and obtain dried red mud powder.

[0077] S2. Weigh 250g of dried red mud and sodium hydroxide and mix them in a planetary ball mill at a mass ratio of 1:1.5 for 3 hours. After thorough mixing, add 100ml of deionized water to the mixture to make a uniform slurry.

[0078] S3. Place the prepared slurry in a crucible and put it into a muffle furnace. Perform an alkaline fusion reaction at 550℃ for 3 hours to promote the transformation of hematite into magnetite, forming a porous sintered structure mineral rich in active iron sites.

[0079] S4. Crush the sintered ore with an agate mortar and sieve it through a 100-mesh sieve. Then, mix the sieved powder with deionized water in a solid-liquid ratio of 1:3 and place it in a water bath. React at 80°C for 90 minutes. Filter to separate the residue and leachate. The leachate can be used to recover sodium aluminate.

[0080] S5. Wash the filter residue repeatedly with hot water at a solid-liquid ratio of 1:10 until neutral to remove residual alkali and impurity ions. Place the washed powder in an oven and dry it at 90°C for 12 hours to prevent the phase transformation of iron oxide and hydroxide, and finally obtain an arsenic adsorbent with a porous structure and high magnetic response.

[0081] This invention also provides an application of arsenic adsorbents.

[0082] Please see Figure 2An application of an arsenic adsorbent, comprising the following steps: The arsenic adsorbent prepared using the method described above for preparing arsenic adsorbents from aluminum electrolysis red mud.

[0083] S01. Arsenic-containing wastewater is sequentially filtered through a bar screen, settled in a sedimentation tank, and filtered through a sand filter to remove suspended solids before being introduced into the purification device.

[0084] S02. Add an adjusting agent to the arsenic-containing wastewater to adjust the pH of the wastewater to 5.0~8.0;

[0085] S03. Add arsenic adsorbent to arsenic-containing wastewater, stir for a preset time, and let stand for 10-20 minutes.

[0086] S04. The treated wastewater is discharged and the arsenic adsorbent enriched with arsenic is separated by magnetic attraction. The wastewater after magnetic attraction enters the next treatment step.

[0087] S05. The arsenic-enriched adsorbent and eluent are mixed at a solid-liquid ratio of 1:(10~20), stirred for 60~120 min, washed with deionized water until neutral after elution, and dried to obtain the regenerated arsenic adsorbent.

[0088] By utilizing the synergistic effect of the core iron-aluminum active sites and porous structure of the above-mentioned arsenic adsorbent, it exhibits high adsorption capacity and selectivity for arsenic, as well as As(III) and As(V) in wastewater, and is unaffected by SO4 in the wastewater. 2- Cl - It is resistant to common anion interference; the adsorption reaction process is simple, relying on the high magnetic responsiveness of maghemite in the arsenic adsorbent, and adopts magnetic separation technology, which avoids problems such as filter membrane clogging and equipment wear, reduces operating energy consumption, and is suitable for the rapid treatment of large volumes of arsenic-containing wastewater.

[0089] Meanwhile, the adsorbent enriched with arsenic can be recycled 3 to 5 times after acid and alkali elution, washing and drying, with the adsorption capacity decreasing by no more than 30%, greatly reducing the amount of adsorbent consumed.

[0090] Among these measures, the pH value of the wastewater to be tested was adjusted to the range of 5.0 to 8.0. This range matches the zero charge point of the adsorbent (pHpzc=6~9), which can ensure the degree of hydroxylation of the iron and aluminum active sites, and avoid the adsorbent dissolution or unstable arsenic ion form caused by extreme pH.

[0091] After adding arsenic adsorbent to SO3, stir for 30-120 minutes. The specific stirring time should be set according to the volume of wastewater to be treated and the arsenic content of the wastewater.

[0092] Preferably, the adjusting agent in SO2 is dilute hydrochloric acid or dilute sodium hydroxide.

[0093] Dilute hydrochloric acid or dilute sodium hydroxide should be used as the pH adjusting agent to avoid introducing additional impurity ions. This step can be performed based on the pH value of the wastewater; when adjusting the pH value using the adjusting agent, the pH value of the wastewater should be measured using a detection device.

[0094] Preferably, sodium hydroxide solution or hydrochloric acid solution is used as the eluent in S05.

[0095] Preferably, a 0.1-0.5 mol / L sodium hydroxide solution or a 5%-10% hydrochloric acid solution is used as the eluent.

[0096] Preferably, the arsenic-enriched adsorbent and the eluent are mixed at a solid-liquid ratio of 1:15 and stirred for 90 min.

[0097] The present invention also provides a purification device.

[0098] Please see Figure 3 and Figure 4 A purification device for the application of the arsenic adsorbent, comprising: a support 1;

[0099] Purification box 2, the purification box 2 includes box body 21, box cover 22 and discharge square tube 23, the box body 21 is installed on the bracket 1, the box cover 22 is installed on the top of the box body 21, the discharge square tube 23 is located on one side of the bottom of the box body 21, and a valve 231 is provided on the discharge square tube 23;

[0100] A stirring device 3 is installed on the box cover 22, and the stirring end extends into the interior of the box body 21;

[0101] Lifting device 4, the lifting device 4 being used to lift the box cover 22;

[0102] The magnetic attraction structure 5 includes a guide box 51 and an electromagnet 52. The guide box 51 is inclined and suspended below the discharge square tube 23, and the electromagnet 52 is installed inside the guide box 51.

[0103] The purification device provided by this invention is mainly used in steps S02 to S04 of the application of arsenic adsorbents.

[0104] In this embodiment, a liquid inlet pipe 211 is connected to the top of one side of the tank 21. The wastewater to be treated is added into the tank 21 through the liquid inlet pipe 211. Of course, the wastewater to be treated can also be added by opening the tank cover 22.

[0105] When in use, add the wastewater to be treated into the tank 21, then add the conditioning agent to the wastewater, and the stirring device 3 will work to stir the wastewater and the conditioning agent to make them mix quickly;

[0106] After the pH value is adjusted, the lifting device 4 is used to lift the box cover 22 and separate it from the box body 21. At this time, arsenic adsorbent can be added into the box body 21. Then, the lifting device 4 lowers the box cover 22 and assembles it with the box body 21. The stirring device 3 continues to work to allow the arsenic adsorbent to fully react with the sewage. The arsenic adsorbent adsorbs the arsenic element in the sewage. After the adsorption is completed, the valve 231 on the discharge square pipe 23 is opened. The treated sewage flows along the guide box 51. The arsenic adsorbent that adsorbs the arsenic element in the sewage is adsorbed by the electromagnet 52 and separated from the treated sewage. After separation, the sewage enters the next treatment step.

[0107] Therefore, this equipment can remove arsenic from wastewater, avoiding arsenic pollution to the ecological environment. Furthermore, the electromagnet 52 can separate the arsenic adsorbent from the treated wastewater, facilitating the recovery of the arsenic adsorbent.

[0108] The purification equipment provided by this invention is mainly used in laboratories or small-scale sewage treatment systems.

[0109] The pH value of the wastewater can be measured by installing a pH sensor inside the tank 21, or by opening the tank cover 22 and inserting a pH testing device into the tank 21 to measure the pH value. The amount of adjusting reagent added is determined based on the volume of the wastewater to be treated and its original pH value; the amount of arsenic adsorbent added is determined based on the volume of the wastewater to be treated and the arsenic content in the wastewater.

[0110] like Figure 3 In one embodiment, a liquid collection box 8 is provided below the discharge square tube 23 and below the magnetic suction structure 5. After the treated wastewater is adsorbed and the arsenic adsorbent is removed by the magnetic suction structure 5, the liquid flows into the liquid collection box 8. Subsequently, the liquid collection box 8 is moved to the next processing step.

[0111] In another embodiment, a square tube can be provided below the magnetic suction structure 5, with an inlet hole at the top of the square tube, and one end of the square tube connected to an infusion pipe, which is connected to the inlet end of the device in the downward processing step.

[0112] Please see Figure 5 The bottom of the inner wall of the box 21 is set as an inclined surface, and the side closest to the discharge square pipe 23 is the lower side, so as to facilitate the guidance of the treated sewage to the discharge square pipe 23 for discharge.

[0113] Please see Figure 5 In this embodiment, the stirring device 3 includes a motor 31, a stirring shaft 32, and a stirring blade 33. The motor 31 is mounted on the box cover 22, the stirring shaft 32 is mounted on the output end of the motor 31, and the stirring blade 33 is mounted on the stirring shaft 32.

[0114] In use, motor 31 drives stirring shaft 32 to rotate, stirring shaft 32 drives stirring blade 33 to rotate, stirring blade 33 drives the wastewater to be treated to rotate, thereby accelerating the contact between wastewater and arsenic adsorbent, speeding up the wastewater treatment process; and it can also accelerate the full mixing of wastewater and adjusting reagent, and quickly adjust the pH of wastewater.

[0115] The lifting device 4 can lift the stirring device 3 to move it out of or near the box 21, thereby facilitating the cleaning and maintenance of the stirring shaft 32 and the stirring blades 33.

[0116] Furthermore, during the mixing process, the height of the lid 22 is adjusted using the lifting device 4, thereby adjusting the height of the mixing device 3, and the mixing speed is increased by mixing at different height positions.

[0117] Please see Figure 4 In this embodiment, the lifting device 4 includes a lifting cylinder 41, a connecting plate 42 and a plurality of positioning rods 43. The lifting cylinder 41 is mounted on the bracket 1. One end of the connecting plate 42 is mounted on the output end of the lifting cylinder 41 and the other end is mounted on the top of the box cover 22. The top end of the positioning rods 43 is mounted on the connecting plate 42.

[0118] A positioning sleeve is installed on the housing 21, and the positioning rod 43 passes through the positioning sleeve.

[0119] When lifting is required, the lifting cylinder 41 lifts the box cover 22 through the connecting plate 42, and the box cover 22 drives the stirring device 3 to move upward, thereby realizing the lifting of the stirring device 3; the positioning rod 43 cooperates with the positioning sleeve to improve the stability of the lifting of the box cover 22.

[0120] The lifting cylinder 41 can be a pneumatic cylinder, a hydraulic cylinder, or an electric push cylinder.

[0121] In other embodiments, the lifting cylinder 41 can be replaced with a screw lifting structure, a belt lifting structure, a chain lifting structure, etc.

[0122] When there is only one magnetic structure 5, the guide box 51 in the magnetic structure 5 is installed on the working ground through the assembly frame.

[0123] When there are two magnetic structures 5, please refer to Figure 3 As an optional embodiment, the purification device further includes a rotating component 6 and a collection box 9. The number of magnetic structures 5 is two, and the two magnetic structures 5 are symmetrically arranged below the box 21. The rotating component 6 is used to drive the two magnetic structures 5 to rotate. The collection box 9 is arranged below one of the magnetic structures 5 away from the discharge square tube 23.

[0124] By setting the number of magnetic structures 5 to two, when a large amount of arsenic adsorbent is adsorbed on the electromagnet 52 of the magnetic structure 5 located below the discharge square tube 23, the valve 231 closes the discharge square tube 23, the rotating part 6 rotates 180 degrees to adjust the position of the two magnetic structures 5, and then the valve 231 is opened to continue discharging the treated wastewater. At this time, the adjusted magnetic structure 5 continues to adsorb the arsenic adsorbent in the wastewater and separate it from the treated wastewater. In the other magnetic structure 5, the power to the electromagnet 52 is turned off, and the arsenic adsorbent adsorbed on the electromagnet 52 enters the collection box 9 for collection. The subsequent operation is the same, so as to maintain the adsorption efficiency of the magnetic structure 5 for the arsenic adsorbent in the treated wastewater, and facilitate the collection of the adsorbed arsenic adsorbent, which is convenient for subsequent elution and regeneration treatment of the arsenic adsorbent.

[0125] In this configuration, the rotating component 6 drives the two magnetic structures 5 to rotate in opposite directions sequentially, which can prevent the wires connected to the electromagnet 52 from being continuously tangled.

[0126] Preferred, such as Figure 4 and Figure 5 The purification device also includes a support platform 10, which supports two magnetic structures 5. Each magnetic structure 5 includes a slide 53, which is installed at the bottom of the guide box 51. The bottom of the slide 53 is provided with a rolling element, which interacts with the top surface of the support platform 10. By setting the support platform 10 to support the magnetic structures 5, the stability of the magnetic structures 5 during operation is improved. By setting the rolling element, the friction between the two magnetic structures 5 and the support platform 10 when they rotate is reduced.

[0127] The rolling element is a ball bearing, which is embedded in the bottom of the guide box 51, or a caster wheel is installed at the bottom of the guide box 51.

[0128] As an optional embodiment, the rotating component 6 includes a rotating shaft 61, a square shaft 63, and two connecting arms 62. The top end of the rotating shaft 61 passes through the purification box 2 and extends into the interior of the purification box 2. The square shaft 63 is installed at the top end of the rotating shaft 61. The rotating shaft 61 is connected to the two guide boxes 51 respectively through the two connecting arms 62.

[0129] The stirring device 3 also includes a drive head 34, which is installed at the bottom end of the stirring shaft 32. A square groove 341 is provided at the bottom end of the drive head 34, and the square groove 341 is suspended above the square shaft 63. The box cover 22 is fitted onto the box body 21.

[0130] After the sewage treatment is completed, the lifting device 4 continues to lower the tank cover 22. The tank cover 22 descends along the tank body 21, simultaneously driving the stirring device 3 to descend, so that the square groove 341 at the bottom of the drive head 34 fits onto the square shaft 63. Figure 6 In (b), when it is necessary to adjust the position of the two magnetic structures 5, the motor 31 drives the stirring shaft 32 to rotate the drive head 34. The drive head 34 drives the rotating shaft 61 to rotate through the square shaft 63. The rotating shaft 61 drives the two magnetic structures 5 to rotate through the connecting arm 62 to adjust their positions.

[0131] Thus, the position of the two magnetic structures 5 can be adjusted using the stirring device 3 without the need for additional drive equipment, simplifying the equipment.

[0132] In the initial state, the square groove 341 at the bottom of the drive head 34 is aligned with the square shaft 63 at the top of the rotating shaft 61. After the solution is mixed, the motor 31 drives the stirring shaft 32 to rotate an integer number of revolutions, so that the square groove 341 at the bottom of the drive head 34 is aligned with the square shaft 63 again.

[0133] The bottom end of the rotating shaft 61 is detachably fitted with a sleeve, and two connecting arms 62 are symmetrically installed on both sides of the sleeve. The connecting arms 62 are detachably connected to the guide box 51.

[0134] As another optional embodiment, the square shaft 63 of the rotating component 6 is replaced with a rotary motor, which is installed at the bottom of the purification box 2, and the rotating shaft 61 is installed at the output end of the rotary motor.

[0135] Please see Figure 3 and Figure 7 As a preferred embodiment, the purification device further includes a pushing device 7, which includes a driving member 71, a sliding frame 72, and a pushing plate 73. The sliding frame 72 is inclinedly suspended above a magnetic structure 5 away from the discharge square tube 23. The pushing plate 73 is slidably mounted on the sliding frame 72. The driving member 71 is used to drive the pushing plate 73 to slide along the sliding frame 72.

[0136] By setting up a pushing device 7, when the rotating part 6 drives the two magnetic structures 5 to rotate and adjust their positions, the electromagnet 52 suspended above the collection box 9 is de-energized. The driving part 71 pushes the push plate 73 to move along the sliding frame 72. The push plate 73 pushes the arsenic adsorbent on the adsorption surface of the electromagnet 52 into the collection box 9, thereby quickly cleaning the arsenic adsorbent on the electromagnet 52.

[0137] The sliding frame 72 is arranged parallel to the corresponding magnetic attraction structure 5, thereby ensuring that the push plate 73 moves along the attraction surface of the corresponding electromagnet 52.

[0138] A mechanical seal is applied at the point where the rotating shaft 61 passes through the housing 21.

[0139] like Figure 5The sliding frame 72 and the push plate 73 are positioned parallel above the guide box 51, so as not to affect the rotation of the magnetic structure 5.

[0140] As an optional embodiment, the drive unit 71 includes a mounting bracket, an electric push cylinder, and a transmission plate. The electric push cylinder is mounted at an angle on the end of the guide box 51 away from the rotating member 6 via the mounting bracket, and remains parallel to the guide box 51. The output end of the electric push cylinder is connected to the push plate 73 via the transmission plate.

[0141] Please see Figure 7 and Figure 8 As another optional embodiment, the driving component 71 includes a driving tube 711, a first pull rope 713, a second pull rope 714 and two winding wheels 712. The top end of the driving tube 711 passes through the bottom end of the housing 21 and is sleeved on the rotating shaft 61. The top end of the driving tube 711 is provided with an insertion hole 701, which is located below the square shaft 63.

[0142] Two winding wheels 712 are sleeved and installed on the drive tube 711. A guide wheel 721 is installed at the end of the sliding frame 72 away from the drive tube 711. One end of the first pull rope 713 is connected to one of the winding wheels 712, and the other end passes around the guide wheel 721 and is connected to the push plate 73. One end of the second pull rope 714 is connected to the other winding wheel 712, and the other end is connected to the push plate 73.

[0143] The bottom end of the drive head 34 is equipped with a drive shaft 343, which is located above the insertion hole 701. The interior of the drive head 34 is connected to the square groove 341 and is provided with a circular cavity 342. The diameter of the circular cavity 342 is larger than the diameter of the square shaft 63.

[0144] In this case, the second pull rope 714 is already wound around the corresponding winding wheel 712 in the initial state, and the first pull rope 713 and the second pull rope 714 are wound in opposite directions on the corresponding winding wheel 712.

[0145] When the pusher device 7 is required, please refer to Figure 6 (b) and Figure 9 The lifting device 4 continues to lower the box cover 22, driving the stirring device 3 to continue lowering, causing the drive head 34 to continue lowering. At this time, the square shaft 63 is located inside the circular cavity 342, and simultaneously the shaft 343 is inserted into the insertion hole 701. The subsequent motor 31 drives the stirring shaft 32 to rotate, and the drive head 34 drives the drive tube 711 to rotate through the drive shaft 343. The drive tube 711 drives the two winding wheels 712 to rotate, one of which winds the first pull rope 713. The first pull rope 713 pulls the push plate 73 to move towards one end of the guide wheel 721, as shown. Figure 10The push plate 73 pushes the arsenic adsorbent to be cleaned on the corresponding electromagnet 52 into the collection box 9; since the diameter of the circular cavity 342 is larger than the diameter of the square shaft 63, that is, the diagonal diameter, the drive head 34 will not drive the square shaft 63 to rotate at this time.

[0146] At the same time, another winding wheel 712 releases the rope to the second pull rope 714, thereby allowing the push plate 73 to move toward one side of the collection box 9. When the push plate 73 is pulled back to its original position, the motor 31 drives the stirring shaft 32 to rotate in the opposite direction. This drive tube 711 drives the two winding wheels 712 to rotate in the opposite direction. At this time, one winding wheel 712 releases the rope to the first pull rope 713, and the other winding wheel 712 retracts the rope to the second pull rope 714. The second pull rope 714 pulls the push plate 73 to move toward the direction of the rotating shaft 61 to its original position, thereby enabling the push plate 73 to assist in cleaning the arsenic adsorbent on the electromagnet 52.

[0147] The push plate 73 slides along the sliding frame 72 through the cooperation of the drive tube 711, the winding wheel 712, the first pull rope 713, and the second pull rope 714, cleaning the arsenic adsorbent on the electromagnet 52. In this embodiment, the drive component 71 can be centrally located at the bottom center of the purification box 2, making the structure of the entire device more concentrated and simplifying the device structure. There is no need to set up an electric push cylinder. It is installed at an angle at the end of the guide box 51 away from the rotating component 6, so that the device occupies a larger space.

[0148] Furthermore, by using the stirring device 3 as a drive, the use of driving equipment is further reduced.

[0149] Furthermore, the stirring device 3 in this invention has three states, including a mixing state for stirring sewage, a switching state for driving the rotating shaft 61 to rotate in order to adjust the position of the two magnetic suction structures 5, and a pushing state for driving the driving component 71 to push the push plate 73 to push the material.

[0150] Preferably, a flange is provided on the top of the drive tube 711, and the insertion hole 701 is formed on the flange.

[0151] The feeding device 7 also includes two guide wheel assemblies 702, such as... Figure 7 Guided by the guide wheel assembly 702, the first pull rope 713 and the second pull rope 714 are guided so that the force of the first pull rope 713 and the second pull rope 714 pulling the push plate 73 is the same as the sliding direction of the push plate 73, thus pulling the push plate 73 better.

[0152] The sliding frame 72 includes two mounting plates and two sliding arms. The two sliding arms are installed between the two mounting plates. One mounting plate is fixed to the bottom of the housing 21. The guide wheel 721 is installed on the other mounting plate. The top of the push plate 73 is provided with a sliding sleeve that is fitted onto the sliding arm to form a sliding assembly. Preferably, a ball bearing is provided inside the sliding sleeve to form a rolling connection with the sliding arm, thereby reducing friction during sliding.

[0153] Preferably, a sealing ring is provided between the drive tube 711 and the rotating shaft 61 to ensure sealing.

[0154] Furthermore, a sealing tube is installed at the bottom of the inner wall of the housing 21, which is sleeved on the outside of the drive tube 711. The drive tube 711 is rotatably connected to the sealing tube, and a sealing ring is installed between the sealing tube and the drive tube 711 to ensure sealing.

[0155] In the initial state, the shaft 343 is aligned with the socket 701.

[0156] Please see Figure 11 As a preferred embodiment of this example, a limiting shaft structure 20 is provided on the sealing tube. The limiting shaft structure 20 includes a shaft body and a first spring. A cylindrical groove is provided at the top of the sealing tube. The bottom end of the shaft body is installed in the cylindrical groove through the first spring. The top end of the shaft body is inserted into the insertion hole 701.

[0157] The shaft can be inserted into the socket 701 to limit the axial movement of the drive tube 711, ensuring that the drive shaft 343 can be smoothly assembled with the socket 701.

[0158] During assembly, after the drive shaft 343 is inserted into the socket 701, it pushes the main shaft to compress the first spring and move it out of the socket 701; and the top of the shaft is embedded with a ball to reduce the friction between the drive tube 711 and the shaft when it rotates.

[0159] Please see Figure 12 As a preferred embodiment of this example, a positioning structure 30 is provided on the support 10. The positioning structure 30 includes an L-shaped frame 301, a U-shaped frame 302, and a second spring 303. The L-shaped frame 301 is installed at the bottom of the support 10. The bottom of the U-shaped frame 302 is connected to the L-shaped frame 301 through the second spring 303. The two top ends of the U-shaped frame 302 pass through the support 10 and are located on both sides of the bottom rolling element of the slide block 53. Both top ends of the U-shaped frame 302 are set as isosceles trapezoids.

[0160] The U-shaped bracket 302 is used to limit the slide 53, thereby limiting the guide box 51, that is, limiting the rotating part 6, so that the square shaft 63 at the top of the rotating shaft 61 can be kept aligned with the square groove 341.

[0161] When the drive magnetic structure 5 rotates, the rolling element presses the isosceles trapezoidal inclined surface at the top of the U-shaped frame 302, causing it to move downward and compress the second spring 303, thus moving it out of the U-shaped frame 302.

[0162] The bottom end of the U-shaped frame 302 is equipped with a limit post, and the second spring 303 is sleeved on the limit post.

[0163] In other embodiments, marking lines can be set on the drive tube 711 and the rotating shaft 61, and marking rods can be set on the bottom of the housing 21. When the marking lines are aligned with the marking rods, the insertion hole 701, the square shaft 63, the drive shaft 343, and the square groove 341 are aligned. During use, observe whether they are aligned. If they are not aligned, rotate and adjust.

[0164] The working principle of the purification device provided by this invention is as follows:

[0165] When in use, add the wastewater to be treated into the tank 21, then add the conditioning agent to the wastewater, and the stirring device 3 will work to stir the wastewater and the conditioning agent to make them mix quickly;

[0166] After the pH value is adjusted, the lifting device 4 is used to lift the box cover 22 and separate it from the box body 21. At this time, arsenic adsorbent can be added into the box body 21. Then, the lifting device 4 lowers the box cover 22 and assembles it with the box body 21. The stirring device 3 continues to work to allow the arsenic adsorbent to fully react with the sewage. The arsenic adsorbent adsorbs the arsenic element in the sewage. After the adsorption is completed, the valve 231 on the discharge square pipe 23 is opened. The treated sewage flows along the guide box 51. The arsenic adsorbent that adsorbs the arsenic element in the sewage is adsorbed by the electromagnet 52 and separated from the treated sewage. After separation, the sewage enters the next treatment step.

[0167] After the sewage treatment is completed, the lifting device 4 continues to lower the tank cover 22. The tank cover 22 descends along the tank body 21, simultaneously driving the stirring device 3 to descend, so that the square groove 341 at the bottom of the drive head 34 is fitted onto the square shaft 63. Figure 6 In (b), when it is necessary to adjust the position of the two magnetic structures 5, the motor 31 drives the stirring shaft 32 to rotate the drive head 34. The drive head 34 drives the rotating shaft 61 to rotate through the square shaft 63. The rotating shaft 61 drives the two magnetic structures 5 to rotate through the connecting arm 62 to adjust their positions.

[0168] The adjusted magnetic structure 5 continues to adsorb the arsenic adsorbent in the wastewater and separate it from the treated wastewater. In another magnetic structure 5, the electromagnet 52 is powered off. At this time, the arsenic adsorbent adsorbed on the electromagnet 52 enters the collection box 9 for collection. The same operation is performed subsequently. This can maintain the adsorption efficiency of the magnetic structure 5 for the arsenic adsorbent in the treated wastewater and facilitate the collection of the adsorbed arsenic adsorbent, which is convenient for subsequent elution and regeneration treatment of the arsenic adsorbent.

[0169] Please see Figure 6 (b) and Figure 9The lifting device 4 continues to lower the box cover 22, which drives the stirring device 3 to continue to lower, causing the drive head 34 to continue to lower. At this time, the square shaft 63 is located in the circular cavity 342, and the shaft 343 is inserted into the insertion hole 701. The subsequent motor 31 drives the stirring shaft 32 to rotate. The drive head 34 drives the drive tube 711 to rotate through the drive shaft 343. The drive tube 711 drives two winding wheels 712 to rotate. One winding wheel 712 winds the first pull rope 713. The first pull rope 713 pulls the push plate 73 to move toward one end of the guide wheel 721. The push plate 73 pushes the arsenic adsorbent to be cleaned on the corresponding electromagnet 52 into the collection box 9.

[0170] At the same time, another winding wheel 712 releases the rope to the second pull rope 714, thereby allowing the push plate 73 to move toward one side of the collection box 9. When the push plate 73 is pulled back to its original position, the motor 31 drives the stirring shaft 32 to rotate in the opposite direction. This drive tube 711 drives the two winding wheels 712 to rotate in the opposite direction. At this time, one winding wheel 712 releases the rope to the first pull rope 713, and the other winding wheel 712 retracts the rope to the second pull rope 714. The second pull rope 714 pulls the push plate 73 to move toward the direction of the rotating shaft 61 to its original position, thereby enabling the push plate 73 to assist in the rapid cleaning of the arsenic adsorbent on the electromagnet 52.

[0171] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for preparing arsenic adsorbent from aluminum electrolytic red mud, characterized in that, Includes the following steps: S1. Select aluminum electrolysis red mud, crush it with a crusher, pass it through a 100-200 mesh sieve, and then dry it to obtain dry red mud powder; S2. Weigh the dried red mud and sodium hydroxide and mix them in a planetary ball mill at a ratio of 1:(1~1.5) for 2~3 hours. After mixing, add deionized water to the mixture to make a slurry. S3. The slurry is subjected to an alkaline fusion reaction at 350℃ for 1.5~3h to transform hematite into magnetite, forming a porous sintered structure mineral with active iron sites. S4. Crush the porous sintered ore, pass it through a 100-200 mesh sieve, mix it with deionized water at a solid-liquid ratio of 1:(3-5), place it in a water bath and react at 70-80℃ for 45-90 minutes, then filter to separate the filter residue and leachate. S5. Wash the filter residue with hot water at 60~80℃ in a solid-liquid ratio of 1:(7~10) until neutral. Place the washed powder in an oven and dry it at 80~90℃ for 12 hours to obtain an arsenic adsorbent with a porous structure and magnetic response.

2. An application of an arsenic adsorbent, characterized in that, The arsenic adsorbent prepared using the method for preparing arsenic adsorbent from aluminum electrolysis red mud as described in claim 1 includes the following steps: S01. Arsenic-containing wastewater is sequentially filtered through a bar screen, settled in a sedimentation tank, and filtered through a sand filter to remove suspended solids before being introduced into the purification device. S02. Add an adjusting agent to the arsenic-containing wastewater to adjust the pH of the wastewater to 5.0~8.0; S03. Add arsenic adsorbent to arsenic-containing wastewater, stir for a preset time, and let stand for 10-20 minutes. S04. The treated wastewater is discharged and the arsenic adsorbent enriched with arsenic is separated by magnetic attraction. The wastewater after magnetic attraction enters the next treatment step. S05. The arsenic-enriched adsorbent and eluent are mixed at a solid-liquid ratio of 1:(10~20), stirred for 60~120 min, washed with deionized water until neutral after elution, and dried to obtain the regenerated arsenic adsorbent.

3. The application of the arsenic adsorbent according to claim 2, characterized in that, The adjusting agent in SO2 is dilute hydrochloric acid or dilute sodium hydroxide.

4. The application of the arsenic adsorbent according to claim 2, characterized in that, Sodium hydroxide solution or hydrochloric acid solution is used as the eluent in S05.

5. A purification device, characterized in that, The application of the arsenic adsorbent as described in any one of claims 2-4 includes: a support; A purification box, comprising a box body, a box cover, and a discharge square tube, wherein the box body is mounted on the bracket, the box cover is mounted on the top of the box body, the discharge square tube is disposed on one side of the bottom of the box body, and a valve is provided on the discharge square tube; A stirring device is installed on the tank cover, and the stirring end extends into the interior of the tank. A lifting device is used to lift the lid of the box. A magnetic attraction structure, comprising a guide box and an electromagnet, wherein the guide box is inclinedly suspended below the discharge square tube, and the electromagnet is installed inside the guide box.

6. The purification device according to claim 5, characterized in that, The stirring device includes a motor, a stirring shaft, and stirring blades. The motor is mounted on the housing cover, the stirring shaft is mounted on the output end of the motor, and the stirring blades are mounted on the stirring shaft.

7. The purification device according to claim 6, characterized in that, The purification device also includes a rotating component and a collection box. There are two magnetic structures, which are symmetrically arranged below the box. The rotating component is used to drive the two magnetic structures to rotate. The collection box is located below one of the magnetic structures away from the discharge square tube.

8. The purification device according to claim 7, characterized in that, The rotating component includes a rotating shaft, a square shaft, and two connecting arms. The top end of the rotating shaft passes through the purification box and extends into the interior of the purification box. The square shaft is installed at the top end of the rotating shaft. The rotating shaft is connected to the two guide boxes via the two connecting arms. The stirring device also includes a drive head, which is installed at the bottom end of the stirring shaft. A square groove is provided at the bottom end of the drive head, and the square groove is suspended above the square shaft. The box cover is fitted onto the box body.

9. The purification device according to claim 8, characterized in that, The purification device also includes a material pushing device, which includes a driving component, a sliding frame, and a push plate. The sliding frame is inclinedly suspended above a magnetic structure away from the discharge square tube. The push plate is slidably mounted on the sliding frame. The driving component is used to drive the push plate to slide along the sliding frame.

10. The purification device according to claim 9, characterized in that, The driving component includes a driving tube, a first pull rope, a second pull rope, and two winding wheels. The top end of the driving tube passes through the bottom end of the housing and is sleeved on the rotating shaft. The top end of the driving tube has an insertion hole located below the square shaft. Two winding wheels are sleeved and installed on the drive tube. A guide wheel is installed at the end of the sliding frame away from the drive tube. One end of the first pull rope is connected to one of the winding wheels, and the other end passes around the guide wheel and is connected to the push plate. One end of the second pull rope is connected to the other winding wheel, and the other end is connected to the push plate. The bottom end of the drive head is equipped with a drive shaft, which is located above the insertion hole. The interior of the drive head is connected to the square groove and has a circular cavity, the diameter of which is larger than the diameter of the square shaft.

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