A device for preparing hydrotalcite by using alkali residue filtrate

Abstract

The utility model relates to the field of abandoned resource utilization and soil improvement technology discloses a device for preparing hydrotalcite by using alkali residue filtrate, which comprises: an alkali residue acid leaching tank, which is communicated with an alkali residue feeding pipe and is used for mixing alkali residue and acetic acid solution to form alkali residue slurry; a plate-and-frame filter press, which is communicated with the alkali residue acid leaching tank and is used for filtering the alkali residue slurry to form filtrate and filter residue; a balance adjusting tank, which is communicated with the plate-and-frame filter press and is used for mixing the filtrate, calcium chloride solution and aluminum nitrate solution to form adjusted filtrate; a high-temperature reaction kettle, which is communicated with the balance adjusting tank and is used for mixing the adjusted filtrate and sodium hydroxide to form precipitated solid; and a centrifugal dehydrator, which is communicated with the high-temperature reaction kettle, and the precipitated solid is sent into the centrifugal dehydrator through a fourth pipeline and hydrotalcite is obtained after centrifugal treatment. Not only is the secondary utilization of alkali residue realized, but also hydrotalcite, which can be used for acidic soil improvement, is prepared by using alkali residue.

Description

Technical Field

[0001] This utility model relates to the field of waste resource utilization and soil improvement technology, and in particular to an apparatus for preparing hydrotalcite using alkaline residue filtrate. Background Technology

[0002] Acidic red soil is widely distributed in southern my country, and soil improvement is generally required to achieve high crop yields. For example, alkaline chemical amendments such as lime can be used to neutralize soil acidity and control soil acidification. However, chemical amendments are expensive, making large-scale, low-cost application difficult.

[0003] In recent years, my country's soda ash production has continued to grow rapidly, leading to a significant increase in the amount of soda ash residue stored, which has become a major limiting factor for the development of the soda ash industry. Currently, the secondary utilization of soda ash residue is severely insufficient, with large amounts of residue occupying land and causing adverse environmental impacts. While soda ash residue contains certain alkaline components, making it suitable as a chemical amendment for acidic soils, its high chloride ion content easily causes soil compaction and poor permeability. Therefore, directly using soda ash residue for acidic soil improvement is not feasible. Utilizing soda ash residue to improve acidic soils would be of great significance for both the secondary utilization of soda ash residue and the improvement of acidic soils.

[0004] Therefore, how to utilize alkaline residue to prepare a soil conditioner suitable for acidic soils is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0005] The purpose of this invention is to provide an apparatus for preparing hydrotalcite using alkaline residue filtrate, so as to solve the problems existing in the prior art.

[0006] To achieve the above objectives, this utility model provides an apparatus for preparing hydrotalcite using alkaline residue filtrate, comprising:

[0007] The alkali residue acid leaching tank is connected to the alkali residue feed pipe and is used to mix the alkali residue with acetic acid solution to form an alkali residue slurry.

[0008] A plate and frame filter press is connected to the alkaline residue leaching tank via a first pipeline. The plate and frame filter press is used to press and filter alkaline residue slurry to form filtrate and filter residue.

[0009] The balancing tank is connected to the plate and frame filter press via a second pipeline. The balancing tank is used to mix the filtrate with calcium chloride solution and aluminum nitrate solution to form a balancing filtrate.

[0010] A high-temperature reactor is connected to the equilibrium adjustment tank via a third pipeline. The high-temperature reactor is used to mix the adjustment filtrate with sodium hydroxide to form a precipitated solid.

[0011] A centrifugal dehydrator is connected to the high-temperature reaction vessel via a fourth pipeline. The precipitated solid is fed into the centrifugal dehydrator through the fourth pipeline and centrifuged to obtain hydrotalcite.

[0012] Furthermore, a first booster pump is installed on the first pipeline, a second booster pump is installed on the second pipeline, a third booster pump is installed on the third pipeline, and a fourth booster pump is installed on the fourth pipeline.

[0013] Furthermore, it also includes: an acetic acid solution storage tank, which is connected to the alkaline residue leaching tank through a first conveying pipeline for adding acetic acid solution to the alkaline residue leaching tank, and a first dosing pump is provided on the first conveying pipeline.

[0014] Furthermore, it also includes:

[0015] A calcium chloride solution storage tank is connected to the balance adjustment tank via a second conveying pipeline for adding calcium chloride solution to the balance adjustment tank. A second dosing pump is installed on the second conveying pipeline.

[0016] An aluminum nitrate solution storage tank is connected to the balance adjustment tank via a third delivery pipeline for adding aluminum nitrate solution to the balance adjustment tank. A third dosing pump is installed on the third delivery pipeline.

[0017] Furthermore, it also includes: a sodium hydroxide solution storage tank, which is connected to the high-temperature reactor via a fourth delivery pipeline for adding sodium hydroxide solution to the high-temperature reactor; the fourth delivery pipeline is equipped with a fourth dosing pump.

[0018] Furthermore, the high-temperature reactor is equipped with an online pH monitoring device and a temperature monitoring device, and a sampling pipeline is provided on the side of the high-temperature reactor.

[0019] This utility model also provides a method for preparing hydrotalcite using alkaline residue filtrate, and an apparatus for preparing hydrotalcite using alkaline residue filtrate, comprising:

[0020] S1: Input the alkali residue into the alkali residue acid leaching tank, add acetic acid solution into the alkali residue acid leaching tank and stir to mix evenly to form alkali residue slurry;

[0021] S2: The alkaline residue slurry is fed into the plate and frame filter press. After dewatering by filtration, filtrate and filter residue are formed. The filter residue is collected by the hopper of the plate and frame filter press.

[0022] S3: Input the filtrate into the equilibrium adjustment tank, add aluminum nitrate solution and calcium chloride solution into the equilibrium adjustment tank and stir to mix evenly to form the conditioned filtrate;

[0023] S4: Input the adjusted filtrate into the high-temperature reactor, add sodium hydroxide solution into the high-temperature reactor to obtain a reaction solution, adjust the pH of the reaction solution to 10-14; heat and stir to carry out the reaction, and obtain a precipitated solid;

[0024] S5: The precipitated solids are fed into a centrifugal dehydrator and centrifuged to obtain hydrotalcite.

[0025] Furthermore, during the pH adjustment of the reaction solution, the stirring speed of the high-temperature reactor is 200-400 r / min; during the heating and stirring process, the stirring speed of the high-temperature reactor is 30-50 r / min, the reaction temperature is 130℃, and the reaction time is 16-48 h.

[0026] Furthermore, the moisture content of the alkali residue is 20% to 30%.

[0027] Furthermore, the concentration of acetic acid solution is 4–6 mol / L, the concentration of aluminum nitrate solution is 0.8–1.6 mol / L, the concentration of calcium chloride solution is 2–4 mol / L, and the concentration of sodium hydroxide solution is 5–8 mol / L.

[0028] The present invention discloses the following technical effects:

[0029] The concentration of calcium ions in the alkali residue filtrate was increased by acid leaching. After adjusting the filtrate with calcium chloride and aluminum nitrate, the pH was adjusted, stirred, heated, and reacted to produce hydrotalcite. This not only achieved the secondary utilization of alkali residue but also produced hydrotalcite suitable for improving acidic soils, demonstrating promising application prospects and a wide range of applicability. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of this utility model;

[0032] The components include: 1. Alkali residue feed pipe; 2. Alkali residue leaching tank; 3. First lift pump; 4. Plate and frame filter press; 5. Hopper; 6. Filter residue discharge mechanism; 7. Second lift pump; 8. Balance regulating tank; 9. Third lift pump; 10. High-temperature reactor; 11. Fourth lift pump; 12. Collection device; 13. Drain pipe; 14. Centrifugal dewatering machine; 15. Acetic acid solution storage tank; 16. First dosing pump; 17. Aluminum nitrate solution storage tank; 18. Third dosing pump; 19. Calcium chloride solution storage tank; 20. Second dosing pump; 21. Sodium hydroxide solution storage tank; 22. Fourth dosing pump; 23. Online pH monitoring device; 24. Sampling pipeline. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0034] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] Example

[0036] This utility model provides an apparatus for preparing hydrotalcite using alkaline residue filtrate, comprising:

[0037] Alkali residue leaching tank 2 is connected to alkali residue feed pipe 1 and is used to mix alkali residue with acetic acid solution to form alkali residue slurry;

[0038] The plate and frame filter press 4 is connected to the alkali residue leaching tank 2 through a first pipeline. The plate and frame filter press 4 is used to press and filter the alkali residue slurry to form filtrate and filter residue.

[0039] The balancing tank 8 is connected to the plate and frame filter press 4 through a second pipeline. The balancing tank 8 is used to mix the filtrate with calcium chloride solution and aluminum nitrate solution to form a balancing filtrate.

[0040] The high-temperature reactor 10 is connected to the equilibrium adjustment tank 8 through a third pipeline. The high-temperature reactor 10 is used to mix the adjustment filtrate with sodium hydroxide to form a precipitated solid.

[0041] Centrifugal dehydrator 14 is connected to high-temperature reactor 10 through a fourth pipeline. The precipitated solid is sent into centrifugal dehydrator 14 through the fourth pipeline and obtained as hydrotalcite after centrifugation.

[0042] In this embodiment, a first lift pump 3 is installed on the first pipeline, a second lift pump 7 is installed on the second pipeline, a third lift pump 9 is installed on the third pipeline, and a fourth lift pump 11 is installed on the fourth pipeline. The first lift pump 3 is a slurry pump to avoid clogging by suspended solids. The second lift pump 7, the third lift pump 9, and the fourth lift pump 11 are all metering pumps.

[0043] In this embodiment, it also includes: an acetic acid solution storage tank 15, which is connected to the alkaline residue leaching tank 2 through a first conveying pipeline, for adding acetic acid solution to the alkaline residue leaching tank 2, and a first dosing pump 16 is provided on the first conveying pipeline.

[0044] In this embodiment, it also includes:

[0045] A calcium chloride solution storage tank 19 is connected to a balance adjustment tank 8 via a second conveying pipeline and is used to add calcium chloride solution to the balance adjustment tank 8. A second dosing pump 20 is installed on the second conveying pipeline.

[0046] The aluminum nitrate solution storage tank 17 is connected to the balance tank 8 through a third delivery pipeline and is used to add aluminum nitrate solution to the balance tank 8. A third dosing pump 18 is installed on the third delivery pipeline.

[0047] In this embodiment, it also includes: a sodium hydroxide solution storage tank 21, which is connected to the high-temperature reactor 10 through a fourth delivery pipeline, for adding sodium hydroxide solution to the high-temperature reactor 10, and a fourth dosing pump 22 is provided on the fourth delivery pipeline.

[0048] In this embodiment, a pH online monitoring device 23 and a temperature monitoring device are installed inside the high-temperature reactor 10, and a sampling pipeline 24 is provided on the side of the high-temperature reactor 10.

[0049] This invention also provides a method for preparing hydrotalcite using alkaline residue filtrate, and applies an apparatus for preparing hydrotalcite using alkaline residue filtrate. Hydrotalcite (LDHs) is a type of two-dimensional anionic clay mineral with a special layered structure, generally expressed by the formula [M]. 1-x 2+ M x 3+ (OH)2] x+ (A n- x / n )·yH2O, the coordination octahedrons of the main layer are composed of metal ions (M) and hydroxyl groups, with positively charged metal ion layers between the hydroxyl groups, including trivalent cations (Al). 3+ Fe 3+ 、C r 3+ (etc.) and divalent cations (Ca) 2+ Mg 2+ Cu 2+ Co2+ Ni 2+ Zn 2+ (etc.). Hydrotalcite is classified according to its M... 2+ and M 3+ Hydrotalcites can be categorized into magnesium aluminum, magnesium iron, calcium aluminum, calcium iron, zinc aluminum, and nickel aluminum types, depending on their composition. Among these, calcium aluminum hydrotalcite incorporates aluminum ions and calcium ions (which have larger ionic radii) into a cation exchange layer, forming a main layer [Ca2Al(OH)6]. + It is composed of anions and H2O molecules in the interlayer region. Calcium aluminum hydrotalcite has an interlayer structure with higher thermal stability, and this embodiment is used to prepare calcium aluminum hydrotalcite.

[0050] The specific steps include:

[0051] S1: Input the alkaline slag with a moisture content of 20%–30% into the alkaline slag acid leaching tank 2, add an acetic acid solution with a concentration of 5 mol / L into the alkaline slag acid leaching tank 2, maintain a solid-liquid ratio of 1:25 and stir to mix evenly to form an alkaline slag slurry; the main components of the alkaline slag include calcium carbonate (CaCO3, mass ratio of 40-60%), calcium sulfate (CaSO4), calcium chloride (CaCl2), calcium oxide (CaO), calcium hydroxide (Ca(OH)2) and other calcium salts. In this embodiment, the calcium salts in the alkaline slag are mainly utilized. 2+ This causes the acetic acid solution to react with the slightly water-soluble calcium salt, releasing Ca. 2+ Increase the Ca content in alkaline residue slurry 2+ Concentration, reducing Ca in subsequent steps 2+ The amount of replenishment.

[0052] S2: The alkaline residue slurry is fed into the plate and frame filter press 4. After dewatering by filtration, filtrate and filter residue are formed. The filter residue is collected by the hopper 5 of the plate and frame filter press 4 and discharged through the filter residue discharge mechanism 6. During the dewatering process, chloride ions are concentrated in the filter residue, while the chloride ion content in the filtrate is greatly reduced, resulting in a low chloride ion impurity content in the finished hydrotalcite, which can be used for soil improvement.

[0053] S3: Input the filtrate into the equilibrium adjustment tank 8, add a 1.2 mol / L aluminum nitrate solution and a 2.5 mol / L calcium chloride solution to the equilibrium adjustment tank 8, start stirring at a speed of 260 r / min, and maintain the Ca concentration in the mixture. 2+ And Al 3+ The concentrations were 0.03 mol / L and 0.008 mol / L, respectively, and the mixture was stirred and stirred until homogeneous to form an adjusted filtrate. In this process, aluminum nitrate mainly provides the Al required for the synthesis of calcium aluminum hydrotalcite. 3+ , with Ca 2+ The main layer of calcium aluminum hydrotalcite is formed, and calcium chloride is used to replenish the Ca in the filtrate. 2+ To compensate for the Ca in the filtrate 2+The insufficient content of Ca ions necessitates the control of Ca content in the synthesis of calcium aluminum hydrotalcite. 2+ / Al 3+ The molar ratio is within a certain range (2-4:1).

[0054] S4: Input the adjusted filtrate into high-temperature reactor 10, add a 6 mol / L sodium hydroxide solution to reactor 10 to obtain a reaction solution, and stir the reactor 10 at a speed of 200-400 r / min. Adjust the pH of the reaction solution to 12 (adjusted by sodium hydroxide solution to maintain a strongly alkaline system); heat to 130℃, adjust the stirring speed to 30-50 r / min, and stir to carry out the reaction for 18 hours to obtain a precipitated solid; the synthesis of hydrotalcite is essentially Ca 2+ And Al 3+ In solution with OH - The reaction produces a layer of positively charged metal hydroxides, which can be provided by strong alkaline conditions. - This neutralizes the positive charge of metal ions, causing them to precipitate together from the solution, forming a homogeneous laminar precursor and preventing the precipitation of a single metal ion (such as Al) first. 3+ Under weakly alkaline conditions, it readily forms Al(OH)3 precipitate first and cannot react with Ca. 2+ (Co-assembly). Furthermore, anions (such as CO32-) need to be embedded in the interlayer of the hydrotalcite. 2- Cl - (etc.) to balance the positive charge of the layers, a strongly alkaline environment (usually pH>10) can suppress interlayer anions (especially weak acid anions, such as CO32-). 2- Protonation of CO3 2- +H + →HCO3 - This ensures that anions exist stably between layers; at the same time, strong alkalinity can prevent the dissolution of metal hydroxides in the layers or structural collapse, ensuring the orderly growth of the layered structure.

[0055] Using aluminum nitrate (Al(NO3)3) as the aluminum source, calcium chloride (CaCl2) as the calcium source, sodium hydroxide (NaOH) as the alkali, and sodium carbonate (Na2CO3) as the interlayer carbonate source, the core chemical equation for synthesizing calcium aluminum carbonate hydrotalcite is as follows:

[0056] 4CaCl2+2Al(NO3)3+14NaOH+Na2CO3+4H2O=Ca4Al2(OH) 12 CO3·4H2O↓+8NaCl+6NaNO3.

[0057] In the reaction, the pH value of the system is adjusted by NaOH to make Ca... 2+ Al 3+ With OH -The Na₂CO₃ provides CO₃²⁻ to form a layered hydroxide framework. 2- As an interlayer equilibrium anion, it enters the interlayer and eventually combines with water of crystallization to form calcium aluminum hydrotalcite precipitate; the by-products are soluble sodium chloride (NaCl) and sodium nitrate (Na2CO3).

[0058] S5: The precipitated solid is fed into the centrifugal dehydrator 14 and centrifuged to obtain hydrotalcite. The hydrotalcite is collected and stored by the collection device 12, and the waste liquid generated by centrifugal dehydration is discharged through the drain pipe 13.

[0059] Application Example 1

[0060] Acidic farmland soil (pH approximately 4.81) was used as the test subject. The collected soil samples were air-dried in the laboratory, impurities were removed, and the soil was crushed, sieved, and mixed thoroughly before use. The soil field capacity was 20.8%, soil electrical conductivity was 238 μS / cm, soil exchangeable acidity was 1.30 cmol / kg, and soil exchangeable Al content was... 3+ 0.50 cmol / kg, soil organic matter 16.9 g / kg, available nitrogen 141 mg / kg, available phosphorus 48.1 mg / kg, available potassium 238 mg / kg.

[0061] The hydrotalcite prepared in the above embodiments was added to the test soil in a certain proportion and thoroughly mixed on a plastic film. Then, 1000g of the mixed soil sample was placed into uniformly sized plastic seedling pots and incubated at room temperature for 7 days. On the 8th day, the soil in the seedling pots was broken up and leveled, and three spinach seedlings of similar growth were transplanted into the topsoil of the seedling pots. During the spinach growth period, the soil moisture content was maintained at about 60% of the field capacity. After 25 days of growth, the spinach was harvested, and soil samples from the potted experiments and the spinach plants were collected.

[0062] The experimental results show that the hydrotalcite prepared using the above-described embodiments has a significant improving effect on acidic farmland soils. Furthermore, with increasing the amount of aluminum hydrotalcite applied, spinach biomass increased significantly, with fresh weight increasing by 3-9 times and dry weight by 3-7 times (Table 1). After application of hydrotalcite, soil pH increased significantly, and soil exchange capacity (Al₂O₃) also increased. 3+ Significantly reduced, with soil acidity and alkalinity approaching fertile soil levels, and soil exchangeable Al content... 3+ The significant reduction also indirectly alleviated the soil acidification problem (Table 2). As can be seen from the above, the hydrotalcite prepared in this embodiment can be applied to the improvement of acidic farmland soil, and has a significant effect on controlling soil acidification and increasing crop yield.

[0063] Table 1. Analysis of changes in fresh and dry weight of spinach under different treatment methods.

[0064] none / 0.92±0.12 0.15±0.03 Hydrotalcite 1％ 3.03±0.56 0.57±0.22 Hydrotalcite 3％ 8.20±0.20 1.06±0.17

[0065] Table 2. Soil pH and exchangeable Al2O3 values ​​corresponding to different treatments. 3+ Change Analysis Table

[0066] none / 4.59±0.10 0.48±0.05 Hydrotalcite 1％ 6.44±0.10 0.15±0.04 Hydrotalcite 3％ 6.72±0.06 0.02±0.00

[0067] Application Example 2

[0068] Acidic farmland soil was used as the test subject, with a soil pH of approximately 4.33 and an EC value of 0.250 mS·cm. -1 Total exchangeable acidity of soil: 4.05 cmol·kg -1 Soil exchangeable Al 3+ 2.70 cmol·kg -1 Organic matter 16.0 g·kg -1 62.1 mg / kg of readily available phosphorus -1 Quick-acting potassium 131 mg / kg -1 Alkaline nitrogen 141 mg·kg -1 .

[0069] Thoroughly mix the air-dried and sieved soil sample with hydrotalcite, then fill 1000g of the mixture into a large-diameter plastic seedling pot. Before transplanting the spinach, water it for 7 days to maintain a balanced moisture level, then transplant 3 spinach seedlings into the seedling pot, maintaining 60% field capacity. Harvest the spinach plants after they reach maturity and collect soil samples.

[0070] The experimental results show that the hydrotalcite prepared using the above-described embodiments has a significant improving effect on acidic farmland soil. After application of hydrotalcite, the fresh weight of spinach, plant calcium concentration, and plant calcium accumulation increased significantly, with the fresh weight of spinach increasing by more than 10 times, the plant calcium concentration increasing by 3%, and the plant calcium accumulation increasing by more than 10 times (Table 3). After application of hydrotalcite, the soil pH increased significantly, and the soil exchange capacity Al increased. 3+ Significantly reduced, with soil pH rising to above 6, approaching the level of fertile soil, and soil exchangeable Al... 3+ The significant reduction also indirectly alleviated the soil acidification problem (Table 4). It can be seen that the hydrotalcite prepared by the above examples can be applied to the improvement of acidic farmland soil, and has a significant effect on controlling soil acidification and increasing crop yield.

[0071] Table 3. Analysis of changes in spinach fresh weight, plant calcium concentration, and plant calcium accumulation under different treatments.

[0072]

[0073] Table 4 Soil pH and exchangeable Al2O3 corresponding to different treatments 3+ Change Analysis Table

[0074]

[0075] Application Example 3

[0076] Acidic farmland soil with a pH of approximately 4.88 was used as the test subject, and a rice-water spinach rotation was adopted. The organic matter content of the tested soil was 29.2 g / kg. -1 40.1 mg / kg of readily available phosphorus -1 Quick-acting potassium 78mg·kg -1 Alkaline nitrogen uptake: 80.3 mg / kg -1 .

[0077] Thoroughly mix the air-dried and sieved soil sample with hydrotalcite, then fill 1000g of the mixture into a large-diameter plastic seedling pot. Before transplanting rice and water spinach, water them for 7 days to maintain a balanced water level. Plant rice and water spinach separately, maintaining appropriate water levels for the crops. Harvest the rice and water spinach plants after they reach maturity, and collect soil samples.

[0078] The experimental results show that the hydrotalcite prepared using the above-described embodiments has a significant effect on improving acidic farmland soils. After application of hydrotalcite, the fresh weight, aboveground calcium concentration, and aboveground magnesium concentration of rice and water spinach increased significantly. The increase in fresh weight of water spinach was over 20%, the increase in aboveground calcium concentration was 16%, and the increase in aboveground magnesium concentration was 38% (Table 5). After application of hydrotalcite, the soil pH, exchangeable calcium, and exchangeable magnesium were significantly improved. The soil pH increased by 0.5 units, and the significant decrease in exchangeable calcium and exchangeable magnesium indirectly alleviated the soil acidification problem (Table 6). It is evident that the hydrotalcite prepared using the above-described embodiments can be applied to the improvement of acidic farmland soils and has a significant effect on controlling soil acidification and increasing crop yield.

[0079] Table 5. Analysis of changes in fresh weight, aboveground calcium, and magnesium in water spinach under different treatments.

[0080]

[0081] Table 6. Changes in soil physicochemical properties after rice and water spinach harvests under different treatments.

[0082]

[0083] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0084] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. An apparatus for preparing hydrotalcite using alkaline residue filtrate, characterized in that, include: The alkali residue acid leaching tank (2) is connected to the alkali residue feed pipe (1) and is used to mix the alkali residue with the acetic acid solution to form an alkali residue slurry. The plate and frame filter press (4) is connected to the alkali residue leaching tank (2) through a first pipeline. The plate and frame filter press (4) is used to press and filter the alkali residue slurry to form filtrate and filter residue. The balancing tank (8) is connected to the plate and frame filter press (4) through a second pipeline. The balancing tank (8) is used to mix the filtrate, calcium chloride solution and aluminum nitrate solution to form a balancing filtrate. The high-temperature reactor (10) is connected to the balance adjustment tank (8) through a third pipeline. The high-temperature reactor (10) is used to mix the adjustment filtrate with sodium hydroxide to form a precipitated solid. The centrifugal dehydrator (14) is connected to the high-temperature reactor (10) through a fourth pipeline. The precipitated solid is sent into the centrifugal dehydrator (14) through the fourth pipeline and is centrifuged to obtain hydrotalcite.

2. The apparatus for preparing hydrotalcite using alkaline residue filtrate according to claim 1, characterized in that, A first booster pump (3) is installed on the first pipeline, a second booster pump (7) is installed on the second pipeline, a third booster pump (9) is installed on the third pipeline, and a fourth booster pump (11) is installed on the fourth pipeline.

3. The apparatus for preparing hydrotalcite using alkaline residue filtrate according to claim 1, characterized in that, Also includes: An acetic acid solution storage tank (15) is connected to the alkaline residue leaching tank (2) via a first conveying pipeline for dispensing acetic acid solution into the alkaline residue leaching tank (2). A first dosing pump (16) is installed on the first conveying pipeline.

4. The apparatus for preparing hydrotalcite using alkaline residue filtrate according to claim 1, characterized in that, Also includes: A calcium chloride solution storage tank (19) is connected to the balance adjustment tank (8) through a second conveying pipeline for adding calcium chloride solution to the balance adjustment tank (8). A second dosing pump (20) is provided on the second conveying pipeline. An aluminum nitrate solution storage tank (17) is connected to the balance adjustment tank (8) via a third delivery pipeline for adding aluminum nitrate solution to the balance adjustment tank (8). A third dosing pump (18) is installed on the third delivery pipeline.

5. The apparatus for preparing hydrotalcite using alkaline residue filtrate according to claim 1, characterized in that, It also includes: a sodium hydroxide solution storage tank (21), which is connected to the high-temperature reactor (10) through a fourth delivery pipeline for adding sodium hydroxide solution to the high-temperature reactor (10), and a fourth dosing pump (22) is provided on the fourth delivery pipeline.

6. The apparatus for preparing hydrotalcite using alkaline residue filtrate according to claim 1, characterized in that, The high-temperature reactor (10) is equipped with an online pH monitoring device (23) and a temperature monitoring device, and a sampling pipeline (24) is provided on the side of the high-temperature reactor (10).

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