Device and method for washing aluminum ash and recycling filtrate

Abstract

The invention provides an aluminum ash washing and filtrate recycling device and method, the aluminum ash washing and filtrate recycling device comprises a washing device, a storage device and an evaporation device, the storage device is communicated with the washing device through a circulating pipeline, and the storage device is communicated with the evaporation device through a connecting pipe IV. The water washing device controls the liquid-solid ratio and the additive content of the aluminum ash hydrolysis reaction through a water injection port, aluminum nitride in the aluminum ash is efficiently hydrolyzed, soluble impurities are efficiently removed, and tail gas is safely treated through an ammonia gas treatment part and a hydrogen recovery part; the storage device not only realizes liquid-solid separation, but also separates hydroxides in filtrate, so that a value-added product is obtained; according to the evaporation recovery device, all aluminum elements contained in the filtrate are recovered, an additional product chlorine salt is obtained through evaporation, and the problems that in the aluminum ash washing process in the general technology, liquid-solid separation is lacked, the cost of single-time use of the filtrate is high, the cost of secondary treatment of the filtrate is high, and materials are difficult to transport due to device dispersion are solved.

Description

Technical Field

[0001] The invention relates to the technical field of evaporation equipment, and in particular to a device and method for washing aluminum ash with water and recycling filtrate. Background Art

[0002] my country's recycled aluminum industry is developing rapidly. It is estimated that the demand for recycled aluminum in my country will be 8,600 kt, 9,800 kt, 10,600 kt and 11,500 kt in 2022-2025, respectively. The secondary aluminum ash generated will be about 90 kt, 100 kt, 110 kt and 120 kt. Adding the previously unprocessed 10,000 kt of aluminum ash, the total amount of unprocessed aluminum ash will be 10,420 kt.

[0003] Secondary aluminum ash is mainly composed of four types of substances: oxides, metallic aluminum, salts and aluminum nitride. Due to the obvious differences in the composition of aluminum ash from different sources and the high recycling cost, 95% of aluminum ash is stored and landfilled. Here, taking the common secondary aluminum ash composition as an example, it is generally 50-65w% Al2O3, 15-30w% AlN, 5-20w% Al, 5-20w% salts and 5-10wt% other substances. When landfilled or stored, aluminum ash will hydrolyze to produce a large amount of ammonia, and the chlorides (NaCl, KCl, CaCl2, MgCl2), fluorides (Na3AlF6, NaF, AlF3, CaF2) and heavy metal ions including cadmium (Cd), lead (Pb), chromium (Cr), copper (Cu) and zinc (Zn) it contains may cause soil and groundwater pollution, seriously affecting environmental quality and human health. When hydrometallurgical treatment of aluminum ash is selected, a high liquid-to-solid ratio is generally used to denitrify, defluorinate and desalinate the aluminum ash. After the treatment is completed, a large amount of filtrate is left. If it is not effectively treated harmlessly, the fluoride, chloride salt and alkaline substances it contains will still pollute the environment, which goes against the original intention of harmlessly treating aluminum ash. Therefore, from the perspective of both economy and environmental protection, the filtrate after the aluminum ash is treated by hydrometallurgy needs to be recycled.

[0004] In most of the patents published in China, water washing is frequently used as a low-cost method for removing impurity elements such as F, Cl, and N from secondary aluminum ash. CN112661425B discloses a method for denitrification of aluminum ash, which achieves efficient dechlorination of aluminum ash through three consecutive steps of high-temperature steam denitrification, silicate stabilization of heavy metals, and water washing dechlorination, but the method does not recycle and recover the filtrate. Regarding the water washing device for aluminum ash, CN112661425B discloses a highly efficient defluorination, dechlorination, and denitrification device for aluminum ash slag, which achieves the removal of aluminum hydroxide coatings produced during the hydrolysis process by designing a stirring device in a vertical ball mill. The device achieves the removal of nitrogen, fluorine, and chlorine elements in aluminum ash, but the device cannot achieve liquid-solid separation, filtrate recovery, and the ball milling of the material at the bottom of the device is not thorough. CN114288603A discloses a secondary aluminum ash denitrification device system and method, wherein a steam inlet pipe is designed in a horizontal ball mill, and aluminum nitride in the aluminum ash is efficiently removed by heating and wet grinding the aluminum ash. However, the device cannot change the liquid-to-solid ratio during the reaction process and cannot recycle and recover the filtrate. Summary of the invention

[0005] The invention provides a device and method for washing aluminum ash with water and recycling filtrate, which are used to solve the defect of lacking recycling and recovery of filtrate in the prior art.

[0006] On the one hand, the present invention provides a device for washing aluminum ash with water and recycling filtrate, comprising: a washing device, a storage device and an evaporation device, the storage device is connected to the washing device through a circulation pipeline, and the storage device and the evaporation device are connected through a connecting pipe four (1).

[0007] Preferably, the water washing device includes a stirring barrel, a feeding port, a water injection port, a waste gas discharge port and a slag discharge port 1 are provided on the outer wall of the stirring barrel, a stirring assembly is provided in the stirring barrel, an ammonia treatment assembly and a hydrogen collection assembly are fixedly connected to the outer wall of the stirring barrel, the water injection port and the slag discharge port 1 are connected to the circulation pipeline, the waste gas discharge port is connected to the air inlet of the ammonia treatment assembly through a connecting pipe 1, the hydrogen collection assembly is connected to the air outlet of the ammonia treatment assembly through a connecting pipe 2, the hydrogen collection assembly is provided with an exhaust port, the ammonia treatment assembly is provided with a liquid injection port 1, a heating pipeline is provided inside the outer wall of the stirring barrel, the air outlet of the heating pipeline is connected to an external steam source, the air inlet of the heating pipeline is a steam injection port, and the air inlet of the steam injection port is connected to the external steam source.

[0008] Preferably, the storage device includes multiple groups of storage tanks and filter presses, the storage tanks are connected to the filter presses through connecting pipe three, a water pump is provided on connecting pipe three, a filter screen and a baffle are fixedly connected to the inner wall of the storage tank, and a slag discharge port two is provided at the lower end of the storage tank.

[0009] Preferably, the circulation pipeline includes connecting pipe five and connecting pipe six, the two ends of connecting pipe five are respectively connected to the slag discharge port one and the liquid inlet of the filter press, connecting pipe seven is connected to the external water source, connecting pipe six is ​​respectively connected to the liquid outlet and water injection port of the storage tank, connecting pipe six is ​​also connected to connecting pipe seven, and connecting pipe six is ​​provided with a water pump two.

[0010] Preferably, the evaporation device includes an evaporation box and a suction filter, the interior of the evaporation box is divided into an upper sedimentation chamber and a lower evaporation chamber by a partition plate, the partition plate includes an inclined baffle plate 2 and a horizontally arranged filter screen 2, a sliding baffle sliding in a horizontal direction is installed on the filter screen 2, the sedimentation chamber is provided with a material injection port and a liquid injection port 2, the liquid injection port 2 is connected to the storage device through a connecting pipe 4, the evaporation chamber is provided with a suction filter port, the suction filter is connected to the suction filter port, a heating tube is provided on the bottom surface of the evaporation chamber, and a slag discharge port 3 is provided on the side wall of the evaporation chamber.

[0011] Preferably, an evaluation system is also included, and the evaluation system is used to evaluate the filtrate in the storage tank to determine whether the filtrate needs to be evaporated and recovered. The evaluation system includes: A sampling assembly is connected to the storage tank and is used to sample the filtrate after each filtrate is injected into the storage tank; A first liquid level sensor is disposed in the storage tank and is used to detect the actual liquid level in the storage tank; A detection component, connected to the sampling component, is used to detect the filtrate sample and determine the concentration of each component in the filtrate; The evaluation module is used to determine the use purpose of the filtrate based on the detection result of the detection component.

[0012] Preferably, the assessment module includes: An information receiving unit, used for receiving the detection result of the detection component; A calculation unit, used for calculating a state evaluation parameter of the filtrate; ; Wherein, W is the state evaluation parameter of the filtrate; M is the total number of main components in the filtrate; ln is the logarithmic function with e as the base; e is the natural base; is the influence coefficient of the concentration of the i-th component in the filtrate on the device loss; is the concentration of the i-th component in the filtrate; is the maximum solubility of the i-th component in the filtrate; is the estimated maximum cost of a single device overhaul; S is the bottom area of ​​the storage tank; L is the liquid level in the storage tank; The cost of evaporating one unit volume of filtrate; is the value of the unit mass of the additional product produced by the i-th component in the filtrate during the filtrate treatment; is the conversion rate of the additional product produced by the i-th component in the filtrate during the filtrate treatment; is the influence coefficient of the concentration of the i-th component in the filtrate on the washing effect of aluminum ash; is the influence coefficient of the pH value of the filtrate on the washing effect of aluminum ash; is the preset optimal pH value of the aluminum ash washing process; P is the actual pH value of the filtrate; It is the calculation basis for the preset pH value deviation; is the preset cost threshold; The result output unit, when the state evaluation parameter W of the filtrate is less than 1, the filtrate is used for continuous recycling, and when the state evaluation parameter W of the filtrate is greater than or equal to 1, the filtrate is evaporated and recovered.

[0013] Preferably, a steam control module is further included, and the steam control module is used to control the steam flow rate of the external steam source input into the steam injection port, and the steam control module includes: A first temperature sensor is disposed in the stirring barrel and is used to detect the actual temperature of the solution in the stirring barrel; A second temperature sensor is disposed in the mixing barrel and is used to detect the air temperature in the mixing barrel; A third temperature sensor is provided at the steam injection port and is used to detect the actual temperature of the input steam; A second liquid level sensor is disposed in the mixing barrel and is used to detect the actual liquid level height in the mixing barrel; A calculation module, used for calculating a target input flow rate of steam; ; Where Q is the target flow rate of steam; is the ratio of pi; is the diameter of the steam injection port; is the dynamic viscosity of steam; B is the distance between the heating pipe and the inner wall of the mixing tank; is the constant pressure specific heat capacity of the solution in the stirring barrel; m is the mass of the solution in the stirring barrel; is the optimal reaction temperature; is the actual temperature of the solution in the mixing tank; t is the preset adjustment time; is the inner wall diameter of the mixing barrel; is the convection heat transfer coefficient between the solution in the mixing tank and the air in the mixing tank; is the actual temperature of the solution in the mixing tank; is the air temperature in the mixing tank; is the thermal conductivity of air; is the constant pressure specific heat capacity of steam; K is the thermal conductivity of steam; is the actual temperature of the steam at the steam injection port; is the liquid level of the solution in the mixing tank; is the thermal conductivity of the mixing barrel material; U is the total length of the heating pipeline; is the density of steam; The communication module is used to transmit the target steam input flow calculated by the calculation module to the external steam source, and control the external steam source to adjust the steam output flow to the target steam flow.

[0014] A method for washing aluminum ash with water and recycling filtrate, which is used to use the above-mentioned device for washing aluminum ash with water and recycling filtrate, is characterized by comprising: Step S1, adding aluminum ash and additives into a stirring barrel, opening a water inlet and adding a solution into the stirring barrel to adjust the solid-liquid ratio; Step S2, introducing high-temperature steam into the steam injection port and starting the stirring component to stir the solid-liquid mixture in the stirring barrel to start the reaction; Step S3, after the reaction is completed, the solid-liquid mixture is subjected to solid-liquid separation, the separated filtrate is passed into a storage tank for static treatment, the precipitated precipitate is deposited at the bottom of the storage tank, and the filtrate is collected after being drawn out of the storage tank; Step S4, re-introducing the filtrate after the static treatment into the stirring barrel to participate in the aluminum ash water washing; Step S5, after the filtrate has been circulated for several times, the filtrate is extracted from the storage tank into an evaporation device for evaporation recovery.

[0015] Preferably, step S5 comprises: Step S51, adding a precipitant into the evaporation device; Step S52, separating the precipitate and the solution by suction filtration; Step S53, heating and evaporating the solution.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The washing device is heated by steam, and the water injection port controls the liquid-solid ratio and additive content of the aluminum ash hydrolysis reaction, thereby achieving efficient hydrolysis of aluminum nitride in the aluminum ash and efficient removal of soluble impurities, and achieving safe tail gas treatment through the ammonia treatment section and the hydrogen recovery section; the storage device not only achieves liquid-solid separation but also separates the hydroxide in the filtrate to obtain a value-added product; the evaporation recovery device not only recovers all the aluminum elements contained in the filtrate but also obtains the additional product chloride salt by evaporation, thereby reducing the problems of lack of liquid-solid separation, high cost of single use of filtrate, high cost of secondary treatment of filtrate and difficulty in material transportation due to the dispersion of the device in the aluminum ash washing process in general technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a schematic structural diagram of the water washing device of the present invention; Figure 3 It is a schematic structural diagram of the evaporation device of the present invention.

[0019] Reference numerals: 1. Connecting pipe 4; 2. Mixing barrel; 3. Feeding port; 4. Water injection port; 5. Steam injection port; 6. Waste gas outlet; 7. Slag outlet 1; 8. Mixing assembly; 9. Ammonia treatment assembly; 10. Hydrogen collection assembly; 11. Connecting pipe 1; 12. Connecting pipe 2; 13. Exhaust port; 14. Liquid injection port 1; 15. Storage tank; 16. Filter press; 17. Connecting pipe 3; 18. Water pump 1; 19. Filter screen 1; 20. Baffle 1; 21. Slag outlet two; 22. Connecting pipe five; 23. Connecting pipe six; 24. Connecting pipe seven; 25. Water pump two; 26. Evaporation box; 261. Sedimentation chamber; 262. Evaporation chamber; 27. Filter; 28. Baffle two; 29. ​​Filter screen two; 30. Sliding baffle; 31. Injection port; 32. Liquid injection port two; 33. Filter port; 34. Heating tube; 35. Slag outlet three; 36. Motor; 37. Stirring rod; 38. Stirring blade. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present invention. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions and technical features between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] Example 1 The present invention provides a device for washing aluminum ash with water and recycling filtrate, such as Figure 1-3 As shown, it includes: a water washing device, a storage device and an evaporation device. The storage device is connected to the water washing device through a circulation pipeline, and the storage device and the evaporation device are connected through a connecting pipe 41.

[0023] Preferably, the water washing device includes a stirring barrel 2, the outer wall of which is provided with a feeding port 3, a water injection port 4, a waste gas discharge port 6 and a slag discharge port 7, a stirring assembly 8 is provided in the stirring barrel 2, the outer wall of the stirring barrel 2 is fixedly connected with an ammonia treatment assembly 9 and a hydrogen collection assembly 10, the water injection port 4 and the slag discharge port 7 are connected with the circulation pipeline, the waste gas discharge port 6 is connected with the air inlet of the ammonia treatment assembly 9 through a connecting pipe 11, the hydrogen collection assembly 10 is connected with the air outlet of the ammonia treatment assembly 9 through a connecting pipe 2 12, the hydrogen collection assembly 10 is provided with an exhaust port 13, the ammonia treatment assembly 9 is provided with a liquid injection port 14, a heating pipeline is provided inside the outer wall of the stirring barrel 2, the air outlet of the heating pipeline is connected with an external steam source, the air inlet of the heating pipeline is a steam injection port 5, and the air inlet of the steam injection port 5 is connected with an external steam source.

[0024] Preferably, the storage device includes multiple groups of storage tanks 15 and filter presses 16, the storage tanks 15 are connected to the filter presses 16 via connecting pipes 17, connecting pipes 17 are provided with water pumps 18, the inner wall of the storage tanks 15 is fixedly connected with a filter screen 19 and a baffle 20, and the lower end of the storage tanks 15 is provided with a slag discharge port 21.

[0025] Preferably, the circulation pipeline includes a connecting pipe five 22 and a connecting pipe six 23, the two ends of the connecting pipe five 22 are respectively connected to the slag discharge port one 7 and the liquid inlet of the filter press 16, the connecting pipe seven 24 is connected to the external water source, the connecting pipe six 23 is respectively connected to the liquid outlet and the water injection port 4 of the storage tank 15, the connecting pipe six 23 is also connected to the connecting pipe seven 24, and the connecting pipe six 23 is provided with a water pump two 25.

[0026] Preferably, the evaporation device includes an evaporation box 26 and a suction filter 27. The interior of the evaporation box 26 is divided into an upper sedimentation chamber 261 and a lower evaporation chamber 262 by a partition plate. The partition plate includes an inclined baffle plate 28 and a horizontally arranged filter screen 29. The filter screen 29 is provided with a sliding baffle 30 that slides in a horizontal direction. The sedimentation chamber 261 is provided with a material injection port 31 and a liquid injection port 32. The liquid injection port 32 is connected to the storage device through a connecting pipe 41. The evaporation chamber 262 is provided with a suction filter port 33. The suction filter 27 is connected to the suction filter port 33. A heating tube 34 is provided on the inner bottom surface of the evaporation chamber 262. A slag discharge port 35 is provided on the side wall of the evaporation chamber 262.

[0027] In this embodiment, the stirring assembly 8 includes a motor 36, which is fixedly connected to the upper surface of the stirring barrel 2. The output end of the motor 36 is fixedly connected to a vertically arranged stirring rod 37. The stirring rod 37 rotates through the upper surface of the stirring barrel 2 and extends into the interior of the stirring barrel 2. A plurality of stirring blades 38 are arranged at intervals at the upper and lower parts of the stirring rod 37.

[0028] The beneficial effects of the above technical solution are: When washing aluminum ash, first open the feed port 3 to add aluminum ash and additives into the stirring barrel 2, open the water injection port 4 to add solution into the stirring barrel 2 to adjust the solid-liquid ratio, and then start the stirring component 8 to stir the solid-liquid mixture. During the stirring process, high-temperature steam is introduced into the steam injection port 5 to adjust the temperature in the stirring barrel 2. The waste gas generated during the washing process is first introduced into the ammonia treatment component 9 to remove ammonia, and the gas treated by removing ammonia is then introduced into the hydrogen collection component 10 to collect hydrogen. After the washing is completed, open the slag discharge port 7, connect it to the filter press 16 through the connecting pipe 5 22 to complete the solid-liquid separation, and pump the filtrate into the storage tank 15 for storage through the water pump 18. The filtrate is placed in the storage tank 15 for static treatment so that the precipitated precipitate is deposited on the bottom of the storage tank 15. After treatment, when the next washing of aluminum ash is required, the filtrate that has been statically treated in the storage tank 15 is pumped into the stirring barrel 2 through the water pump 25 to circulate and participate in the reaction. After the filtrate is extracted, the slag outlet 21 is opened to collect the sediment deposited on the bottom of the storage tank 15. After the filtrate has been circulated for many times, the filtrate is extracted into the evaporation box 26 through the connecting pipe 41. After the filtrate is extracted into the evaporation box 26, a precipitant is added into the precipitation chamber 261 through the injection port 31 to precipitate the filtrate. After adding the precipitant for a certain period of time, the sliding baffle 30 is opened, and the filtrate is pumped into the evaporation chamber 262 through the filter screen 29 through the suction filter 27. When all the filtrate enters the evaporation chamber 262, the heating tube 34 is opened to evaporate the filtrate. After the evaporation is completed, the evaporation residue is taken out through the slag outlet 35.

[0029] By setting up multiple groups of storage tanks 15, each group of storage tanks 15 stores solutions in different states. When one storage tank 15 is standing still, the solution in another storage tank 15 that has been standing still can be pumped into the stirring barrel 2 to participate in the reaction, thereby ensuring the continuity of aluminum ash treatment and improving the aluminum ash treatment efficiency. The water washing device is heated by steam to ensure the temperature stability in the stirring barrel 2. The water injection port 4 controls the liquid-solid ratio and additive content of the aluminum ash hydrolysis reaction, thereby achieving efficient hydrolysis of aluminum nitride in the aluminum ash and efficient removal of soluble impurities. The water washing process is stirred by the stirring component 8 to break the aluminum hydroxide coating produced by the hydrolysis of the aluminum nitride particles, ensuring that the aluminum nitride is fully hydrolyzed and improving the reaction efficiency. The temperature in the stirring barrel 2 is kept stable by introducing high-temperature steam. The high efficiency of the reaction process is ensured. By processing and collecting ammonia and hydrogen in the reaction waste gas, the safe treatment of the tail gas is ensured, and two economic products, ammonia water and hydrogen, are obtained. The storage device not only realizes liquid-solid separation and also separates the hydroxide in the filtrate to obtain value-added products; the evaporation recovery device not only realizes the full recovery of the aluminum element contained in the filtrate and also obtains the additional product chloride salt through evaporation, thereby improving the economic benefits of the aluminum ash treatment process. Through multiple cycles of the filtrate, a high utilization rate of the filtrate is ensured, and the water consumption in the aluminum ash washing process is reduced. The multiple cycles of the filtrate reduce the discharge of wastewater and reduce the cost of the aluminum ash washing process. Multiple cycles of the filtrate can increase the output of additional products in the filtrate treatment process, thereby further reducing the cost of the filtrate treatment.

[0030] Example 2 Based on Example 1, an evaluation system is also included. The evaluation system is used to evaluate the filtrate in the storage tank 15 to determine whether the filtrate needs to be evaporated and recovered. The evaluation system includes: A sampling assembly, connected to the storage tank 15, for sampling the filtrate after each injection of the filtrate into the storage tank 15; A first liquid level sensor is disposed in the storage tank 15 and is used to detect the actual liquid level in the storage tank 15; A detection component, connected to the sampling component, is used to detect the filtrate sample and determine the concentration of each component in the filtrate; The evaluation module is used to determine the use purpose of the filtrate based on the detection result of the detection component.

[0031] Preferably, the assessment module includes: An information receiving unit, used for receiving the detection result of the detection component; A calculation unit, used for calculating a state evaluation parameter of the filtrate; ; Wherein, W is the state evaluation parameter of the filtrate; M is the total number of main components in the filtrate; ln is the logarithmic function with e as the base; e is the natural base; is the influence coefficient of the concentration of the i-th component in the filtrate on the device loss; is the concentration of the i-th component in the filtrate; is the maximum solubility of the i-th component in the filtrate; is the estimated maximum cost required for a single device overhaul; S is the bottom area of ​​the storage tank 15; L is the liquid level in the storage tank 15; The cost of evaporating one unit volume of filtrate; is the value of the unit mass of the additional product produced by the i-th component in the filtrate during the filtrate treatment; is the conversion rate of the additional product produced by the i-th component in the filtrate during the filtrate treatment; is the influence coefficient of the concentration of the i-th component in the filtrate on the washing effect of aluminum ash; is the influence coefficient of the pH value of the filtrate on the washing effect of aluminum ash; is the preset optimal pH value of the aluminum ash washing process; P is the actual pH value of the filtrate; It is the calculation basis for the preset pH value deviation; is the preset cost threshold; The result output unit, when the state evaluation parameter W of the filtrate is less than 1, the filtrate is used for continuous recycling, and when the state evaluation parameter W of the filtrate is greater than or equal to 1, the filtrate is evaporated and recovered.

[0032] In this embodiment, the main component of the filtrate refers to a component whose content in the filtrate is higher than a preset content value.

[0033] In this embodiment, the uses of the filtrate include: recycling the filtrate and evaporating and recovering the filtrate.

[0034] The beneficial effects of the above technical solution are: After the filtrate is injected into the storage tank 15 after each circulation, a small amount of sample is extracted from the storage tank 15 by the sampling component and sent to the detection component for detection of the filtrate sample to determine the concentration of each component in the filtrate. The filtrate is evaluated based on the concentration of each component in the filtrate to determine whether the filtrate continues to participate in the circulation or is evaporated and recovered.

[0035] When evaluating the filtrate, the impact of the main components in the filtrate on the device is considered. If the concentration of some components is too high, the precipitation will accelerate the blockage, corrosion and damage of the device, which will increase the difficulty of device maintenance, prolong the maintenance time, increase the cost of materials used, and thus increase the cost of maintenance. Converted into an estimate of the cost of the unit overhaul, taking into account the value of the additional products produced during the filtrate recovery process and the cost of the filtrate recovery process , and the estimated cost of continuing to use the filtrate is obtained, and then the pH value of the filtrate and the influence of the main components in the filtrate on the effect of the aluminum ash washing reaction are considered. As the number of cycles increases, the concentration of impurities in the solution may gradually increase. This may cause the solution to reduce the adsorption capacity of impurities in aluminum ash, thereby affecting the washing effect. The cost of continuing to use the filtrate is calculated by Correction calculations are performed. When the continued use of the filtrate is lower than the preset cost threshold, the filtrate is used for continued recycling. When the continued use of the filtrate is greater than or equal to the preset cost threshold, the filtrate is evaporated and recovered. This ensures that the filtrate is recycled to the greatest extent possible, thus avoiding damage to the device caused by excessive filtrate recycling and a significant decrease in the aluminum ash washing effect.

[0036] Example 3 On the basis of embodiment 1 or 2, a steam control module is further included, and the steam control module is used to control the steam flow rate of the external steam source input into the steam injection port 5, and the steam control module includes: A first temperature sensor is disposed in the stirring barrel 2 and is used to detect the actual temperature of the solution in the stirring barrel 2; A second temperature sensor is disposed in the mixing barrel 2 and is used to detect the air temperature in the mixing barrel 2; A third temperature sensor is provided at the steam injection port 5 and is used to detect the actual temperature of the input steam; The second liquid level sensor is disposed in the mixing barrel 2 and is used to detect the actual liquid level height in the mixing barrel 2; A calculation module, used for calculating a target input flow rate of steam; ; Where Q is the target flow rate of steam; is the ratio of pi; is the diameter of the steam injection port 5; is the dynamic viscosity of steam; B is the distance between the heating pipeline and the inner wall of the mixing barrel 2; is the constant pressure specific heat capacity of the solution in the stirring barrel 2; m is the mass of the solution in the stirring barrel 2; is the optimal reaction temperature; is the actual temperature of the solution in the stirring barrel 2; t is the preset adjustment time; is the inner wall diameter of the mixing barrel 2; is the convection heat transfer coefficient between the solution in the stirring barrel 2 and the air in the stirring barrel 2; is the actual temperature of the solution in the stirring barrel 2; is the air temperature in the mixing barrel 2; is the thermal conductivity of air; is the constant pressure specific heat capacity of steam; K is the thermal conductivity of steam; is the actual temperature of the steam at the steam injection port 5; is the liquid level of the solution in the stirring barrel 2; is the thermal conductivity of the material of the mixing barrel 2; U is the total length of the heating pipeline; is the density of steam; The communication module is used to transmit the target steam input flow calculated by the calculation module to the external steam source, and control the external steam source to adjust the steam output flow to the target steam flow.

[0037] The beneficial effects of the above technical solution are: By monitoring the actual temperature of the solution in the stirring barrel 2, the actual temperature of the air in the stirring barrel 2 and the actual temperature of the input steam, the flow rate of the steam is adjusted in real time to ensure that the temperature of the solution in the stirring barrel 2 is always at the optimal reaction temperature. By adjusting the flow rate of the steam in real time, it is ensured that the temperature of the solution is always in a stable state, and the heat released by the reaction will not fluctuate due to different reaction rates, which will cause fluctuations in the temperature of the solution. By calculating the difference between the target temperature and the current solution temperature, the total amount of heat required for correction is obtained, and then according to the preset adjustment time, the difference between the required natural heat dissipation rate of the solution and the heating rate of the solution by the inner wall of the stirring barrel 2 is calculated. The temperature adjustment is completed based on the difference, so as to complete the temperature adjustment within the specified time. Moreover, since the calculation of the target flow rate of the steam is continuous, as the actual solution temperature approaches the optimal reaction temperature, the difference between the natural heat dissipation rate of the solution and the heating rate of the solution by the inner wall of the stirring barrel 2 will gradually decrease, thereby ensuring that the temperature can be stably controlled at the optimal reaction temperature, avoiding the increase of the temperature deviation value caused by excessive adjustment.

[0038] Example 4 A method for washing aluminum ash with water and recycling the filtrate, for using the device for washing aluminum ash with water and recycling the filtrate described in any one of Examples 1 to 3, characterized by comprising: Step S1, adding aluminum ash and additives into the stirring barrel 2, opening the water injection port 4 to add solution into the stirring barrel 2 to adjust the solid-liquid ratio; Step S2, high-temperature steam is introduced into the steam injection port 5 and the stirring component 8 is started to stir the solid-liquid mixture in the stirring barrel 2 to start the reaction; Step S3, after the reaction is completed, the solid-liquid mixture is subjected to solid-liquid separation, the separated filtrate is passed into the storage tank 15 for static treatment, the precipitated precipitate is deposited at the bottom of the storage tank 15, and the filtrate is collected after being drawn out of the storage tank 15; Step S4, re-introducing the filtrate after the static treatment into the stirring barrel 2 to participate in the aluminum ash water washing; Step S5, after the filtrate has been circulated for several times, the filtrate is extracted from the storage tank 15 into an evaporation device for evaporation recovery.

[0039] Preferably, step S5 comprises: Step S51, adding a precipitant into the evaporation device; Step S52, separating the precipitate and the solution by suction filtration; Step S53, heating and evaporating the solution.

[0040] The beneficial effects of the above technical solution are: Through multiple circulations of the filtrate, a high utilization rate of the filtrate is ensured, and the water consumption in the aluminum ash washing process is reduced. Multiple circulations of the filtrate reduce the discharge of wastewater and reduce the cost of the aluminum ash washing process. Multiple circulations of the filtrate can increase the output of additional products in the filtrate treatment process, thereby further reducing the cost of filtrate treatment.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for washing aluminum ash and recycling filtrate, characterized in that: include: A water washing device, a storage device and an evaporation device, wherein the storage device is connected to the water washing device through a circulation pipeline, and the storage device and the evaporation device are connected through a connecting pipe four (1).

2. The device for washing aluminum ash and recycling filtrate according to claim 1 is characterized in that: The water washing device comprises a stirring barrel (2), wherein the outer wall of the stirring barrel (2) is provided with a feeding port (3), a water injection port (4), a waste gas discharge port (6) and a slag discharge port (7), a stirring assembly (8) is arranged in the stirring barrel (2), an ammonia treatment assembly (9) and a hydrogen collection assembly (10) are fixedly connected to the outer wall of the stirring barrel (2), the water injection port (4) and the slag discharge port (7) are communicated with a circulation pipeline, and the waste gas discharge port (6) and the air inlet of the ammonia treatment assembly (9) are connected via a connecting pipe (1). The mixing barrel (2) is connected to the mixing barrel (11), the hydrogen collecting assembly (10) is connected to the gas outlet of the ammonia processing assembly (9) through the connecting pipe (12), the hydrogen collecting assembly (10) is provided with a gas outlet (13), the ammonia processing assembly (9) is provided with a liquid injection port (14), a heating pipeline is provided inside the outer wall of the mixing barrel (2), the gas outlet of the heating pipeline is connected to the external steam source, the gas inlet of the heating pipeline is the steam injection port (5), and the gas inlet of the steam injection port (5) is connected to the external steam source.

3. The device for washing aluminum ash and recycling filtrate according to claim 2 is characterized in that: The storage device comprises a plurality of storage tanks (15) and a filter press (16). The storage tanks (15) are connected to the filter press (16) via a connecting pipe (17). A water pump (18) is arranged on the connecting pipe (17). A filter screen (19) and a baffle (20) are fixedly connected to the inner wall of the storage tank (15). A slag discharge port (21) is arranged at the lower end of the storage tank (15).

4. The device for washing aluminum ash and recycling filtrate according to claim 3 is characterized in that: The circulation pipeline comprises a connecting pipe five (22) and a connecting pipe six (23). The two ends of the connecting pipe five (22) are respectively connected to the slag discharge port one (7) and the liquid inlet of the filter press (16). The connecting pipe seven (24) is connected to an external water source. The connecting pipe six (23) is respectively connected to the liquid outlet and the water injection port (4) of the storage tank (15). The connecting pipe six (23) is also connected to the connecting pipe seven (24). The connecting pipe six (23) is provided with a water pump two (25).

5. The device for washing aluminum ash and recycling filtrate according to claim 1 is characterized in that: The evaporation device comprises an evaporation box (26) and a suction filter (27). The interior of the evaporation box (26) is divided into an upper sedimentation chamber (261) and a lower evaporation chamber (262) by a partition plate. The partition plate comprises an inclined baffle plate (28) and a horizontally arranged filter screen (29). The filter screen (29) is provided with a sliding baffle plate (30) that slides in a horizontal direction. The sedimentation chamber (261) is provided with a material injection port (31) and a second liquid injection port (32). The second liquid injection port (32) is connected to a storage device through a connecting pipe (1). The evaporation chamber (262) is provided with a suction filter port (33). The suction filter (27) is connected to the suction filter port (33). The inner bottom surface of the evaporation chamber (262) is provided with a heating pipe (34). The side wall of the evaporation chamber (262) is provided with a slag discharge port (35).

6. The device for washing aluminum ash and recycling filtrate according to claim 3 is characterized in that: The device also includes an evaluation system, which is used to evaluate the filtrate in the storage tank (15) to determine whether the filtrate needs to be evaporated and recovered. The evaluation system includes: a sampling assembly, connected to the storage tank (15), and used for sampling the filtrate each time the filtrate is injected into the storage tank (15); A first liquid level sensor is disposed in the storage tank (15) and is used to detect an actual liquid level in the storage tank (15); A detection component, connected to the sampling component, is used to detect the filtrate sample and determine the concentration of each component in the filtrate; The evaluation module is used to determine the use purpose of the filtrate based on the detection result of the detection component.

7. The device for washing aluminum ash and recycling filtrate according to claim 6 is characterized in that: The assessment modules include: An information receiving unit, used for receiving the detection result of the detection component; A calculation unit, used for calculating a state evaluation parameter of the filtrate; ； Wherein, W is the state evaluation parameter of the filtrate; M is the total number of main components in the filtrate; ln is the logarithmic function with e as the base; e is the natural base; is the influence coefficient of the concentration of the i-th component in the filtrate on the device loss; is the concentration of the i-th component in the filtrate; is the maximum solubility of the i-th component in the filtrate; is the estimated maximum cost required for a single device overhaul; S is the bottom area of ​​the storage tank (15); L is the liquid level in the storage tank (15); The cost required to evaporate one unit volume of filtrate; is the value of the unit mass of the additional product produced by the i-th component in the filtrate during the filtrate treatment; is the conversion rate of the additional product produced by the i-th component in the filtrate during the filtrate treatment; is the influence coefficient of the concentration of the i-th component in the filtrate on the washing effect of aluminum ash; is the influence coefficient of the pH value of the filtrate on the washing effect of aluminum ash; is the preset optimal pH value of the aluminum ash washing process; P is the actual pH value of the filtrate; It is the calculation basis for the preset pH value deviation; is the preset cost threshold; The result output unit, when the state evaluation parameter W of the filtrate is less than 1, the filtrate is used for continuous recycling, and when the state evaluation parameter W of the filtrate is greater than or equal to 1, the filtrate is evaporated and recovered.

8. The device for washing aluminum ash with water and recycling filtrate according to claim 2 is characterized in that: It also includes a steam control module, which is used to control the steam flow rate of the external steam source input into the steam injection port (5), and the steam control module includes: A first temperature sensor is disposed in the stirring barrel (2) and is used to detect the actual temperature of the solution in the stirring barrel (2); A second temperature sensor is disposed in the mixing barrel (2) and is used to detect the air temperature in the mixing barrel (2); A third temperature sensor is arranged at the steam injection port (5) and is used to detect the actual temperature of the input steam; A second liquid level sensor is disposed in the mixing barrel (2) and is used to detect the actual liquid level height in the mixing barrel (2); A calculation module, used for calculating a target input flow rate of steam; ； Where Q is the target flow rate of steam; is pi; is the diameter of the steam injection port (5); is the dynamic viscosity of the steam; B is the distance between the heating pipeline and the inner wall of the stirring barrel (2); is the constant-pressure specific heat capacity of the solution in the stirring barrel (2); m is the mass of the solution in the stirring barrel (2); is the optimal reaction temperature; is the actual temperature of the solution in the stirring barrel (2); t is the preset adjustment time; is the inner wall diameter of the mixing barrel (2); is the convection heat transfer coefficient between the solution in the stirring barrel (2) and the air in the stirring barrel (2); is the actual temperature of the solution in the stirring barrel (2); is the air temperature in the mixing barrel (2); is the thermal conductivity of air; is the constant pressure specific heat capacity of steam; K is the thermal conductivity of steam; is the actual temperature of the steam at the steam injection port (5); is the liquid level of the solution in the stirring barrel (2); is the thermal conductivity of the material of the mixing barrel (2); U is the total length of the heating pipeline; is the density of steam; The communication module is used to transmit the target steam input flow calculated by the calculation module to the external steam source, and control the external steam source to adjust the steam output flow to the target steam flow.

9. A method for washing aluminum ash and recycling the filtrate, applied to the device for washing aluminum ash and recycling the filtrate as claimed in any one of claims 1 to 8, characterized in that: include: Step S1, adding aluminum ash and additives into a stirring barrel (2), opening a water inlet (4) and adding a solution into the stirring barrel (2) to adjust the solid-liquid ratio; Step S2, high-temperature steam is introduced into the steam injection port (5) and the stirring component (8) is started to stir the solid-liquid mixture in the stirring barrel (2) to start the reaction; Step S3, after the reaction is completed, the solid-liquid mixture is subjected to solid-liquid separation, the separated filtrate is passed into a storage tank (15) for static treatment, the precipitated precipitate is deposited at the bottom of the storage tank (15), and the filtrate is collected after it is drawn out of the storage tank (15); Step S4, re-introducing the filtrate after the static treatment into the stirring barrel (2) to participate in the aluminum ash water washing; Step S5, after the filtrate is circulated several times, the filtrate is extracted from the storage tank (15) into an evaporation device for evaporation recovery.

10. The method for washing aluminum ash and recycling filtrate according to claim 9, characterized in that: Step S5 includes: Step S51, adding a precipitant into the evaporation device; Step S52, separating the precipitate and the solution by suction filtration; Step S53, heating and evaporating the solution.

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