Judgment method for recovery efficiency of metallic aluminum in aluminum ash
By combining crushing, sieving, and thermal melting with ash particle size calculation, the problems of low aluminum recovery rate and long detection time in aluminum ash were solved, and rapid and accurate assessment of aluminum content in aluminum ash was achieved.
Patent Information
- Application Number
- CN202511705780.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-20
- Publication Date
- 2026-02-17
AI Technical Summary
Existing technologies have low aluminum recovery rates in aluminum ash, long detection times, and large errors, making it difficult to quickly and accurately determine the aluminum content in aluminum ash.
The aluminum ash sample was crushed and sieved, the smelting furnace was heated to the target temperature and stirred, and then weighed after cooling. The aluminum content was calculated by combining the calorific value and particle size of the ash slag. A multi-factor collaborative judgment method was used to quickly evaluate the recovery efficiency of metallic aluminum in aluminum ash.
It enables rapid and accurate assessment of the recovery efficiency of metallic aluminum in aluminum ash within one hour, reducing detection time and errors.
Smart Images
Figure CN121540580A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aluminum ash resource utilization technology, and in particular to a method for judging the recovery efficiency of metallic aluminum in aluminum ash. Background Technology
[0002] Aluminum ash is a solid waste generated during the electrolysis, processing, and recycling processes in aluminum production. For every ton of aluminum produced, 150-290 kg of aluminum ash is generated. The aluminum (Al) in aluminum ash mainly exists in the form of metallic Al, Al₂O₃, and AlN. Currently, the most common and mature method for resource utilization of aluminum ash is the extraction of metallic aluminum. Primary aluminum ash contains approximately 70-80% metallic aluminum, while secondary aluminum ash contains approximately 5-20% metallic aluminum.
[0003] Methods for determining the aluminum content in aluminum ash include plasma methods, electrostatic separation, and titration. However, these methods suffer from low aluminum recovery rates, high energy consumption, and difficult residue treatment. Ash recovery through ash frying is the most common method used by small-scale aluminum ash processing companies. This method utilizes the heat carried by the aluminum ash itself to raise the temperature, causing the aluminum to melt and separate from other substances. After collection and cooling, the aluminum content in the ash is calculated. However, this method has significant errors when determining the aluminum content in low-alumina aluminum ash using thermal melting. The ash residue after melting and cooling still contains a small amount of aluminum, requiring further detection through chemical reactions, which typically takes 2-3 hours. Therefore, a rapid, accurate, and efficient method is needed to determine the aluminum content in aluminum ash. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for judging the recovery efficiency of metallic aluminum in aluminum ash.
[0005] To solve the above technical problems, the technical solution of the present invention is as follows: A method for determining the aluminum recovery efficiency in aluminum ash includes: The aluminum ash sample was crushed and sieved. Control the furnace temperature to the target temperature, weigh out the target mass of aluminum ash, add it to the furnace and stir continuously; After stirring, pour the molten aluminum obtained from the smelting into a dried iron tray, cool it, and then weigh it. The ash and slag in the smelting furnace are weighed, and their calorific value and particle size are determined. The aluminum content in the aluminum ash sample is calculated using the formula: Aluminum content in aluminum ash sample = Molten aluminum content + Aluminum content in ash residue; The formula for calculating the molten aluminum content is: Molten aluminum content = Mass of aluminum block after melting and cooling / Mass of aluminum ash weighed. When the ash particle size is within the first threshold range, the formula for calculating the aluminum content in the ash is: ash calorific value * 1.16%. When the ash particle size is within the second threshold range, the formula for calculating the aluminum content in the ash is: ash calorific value * 1.35%.
[0006] As a preferred embodiment of the method for determining the aluminum recovery efficiency in aluminum ash according to the present invention, the particle size of the pulverized aluminum ash sample is 0.15-2 mm.
[0007] In a preferred embodiment of the method for determining the aluminum recovery efficiency in aluminum ash described in this invention, the heating rate of the smelting furnace is 30°C / min.
[0008] As a preferred embodiment of the method for determining the aluminum recovery efficiency in aluminum ash described in this invention, the target temperature of the smelting furnace is 750-900 ℃.
[0009] As a preferred embodiment of the method for determining the aluminum recovery efficiency in the aluminum ash described in this invention, the target mass of the aluminum ash is 200-250g.
[0010] As a preferred embodiment of the method for judging the aluminum recovery efficiency in the aluminum ash described in this invention, the stirring time of the aluminum ash in the smelting furnace is 10-15 min.
[0011] As a preferred embodiment of the method for determining the aluminum recovery efficiency in aluminum ash described in this invention, the drying temperature of the iron tray is 105℃ and the drying time is 1.5-3h.
[0012] As a preferred embodiment of the method for determining the aluminum recovery efficiency in aluminum ash according to the present invention, the first threshold range of the ash particle size is 0.425-2 mm, and the second threshold range of the ash particle size is 0.15-0.425 mm.
[0013] The beneficial effects of this invention are: This invention uses hot melting as the main method and multiple factors such as calorific value to determine the content of metallic aluminum in aluminum ash, and can quickly assess the recovery efficiency of metallic aluminum in aluminum ash within one hour. Attached Figure Description
[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0015] Figure 1This is a flowchart illustrating the method for determining the aluminum recovery efficiency in aluminum ash provided by the present invention. Detailed Implementation
[0016] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.
[0017] This application provides a method for determining the aluminum recovery efficiency in aluminum ash, which specifically includes the following steps: Step S101: Crush and sieve the aluminum ash sample.
[0018] Specifically, the aluminum ash sample is crushed to make the particle size distribution between 0.15-2 mm, and then the crushed aluminum ash sample is sieved.
[0019] In addition, the calorific value, aluminum nitride content, and moisture content of the aluminum ash samples were determined after sieving. The results showed that the moisture content of the sieved aluminum ash samples was 0.97-2.93%, the AlN content was 3.98-10.13%, and the calorific value was 576-1293 cal / g.
[0020] Step S102: Control the furnace temperature to the target temperature, weigh the target mass of aluminum ash and add it to the furnace while stirring continuously.
[0021] Specifically, control the temperature of the smelting furnace to 750-900 ℃ and control the heating rate to 30 ℃ / min. After the smelting furnace reaches the target temperature, weigh 200-250g of sieved aluminum ash, add it to the smelting furnace and stir continuously for 10-15 min.
[0022] Step S103: After stirring, pour the molten aluminum obtained from the smelting into a dried iron tray, cool it, and then weigh it.
[0023] Specifically, the iron tray is pre-dried in an oven at 105℃ for 1.5-3 hours. After stirring, the molten aluminum is poured into the iron tray. After the aluminum cools, the mass of the cooled aluminum block in the tray is measured.
[0024] Step S104: Weigh the ash and slag in the smelting furnace and determine the calorific value and particle size of the ash and slag.
[0025] Specifically, a certain mass of smelting cold ash is weighed and its calorific value, aluminum nitride content, and particle size are determined.
[0026] Step S105: Calculate the aluminum content in the aluminum ash sample. The calculation formula is: Aluminum content in aluminum ash sample = Molten aluminum content + Aluminum content in ash slag; The formula for calculating the molten aluminum content is: Molten aluminum content = Mass of aluminum block after melting and cooling / Mass of aluminum ash weighed. When the ash particle size is within the first threshold range, the formula for calculating the aluminum content in the ash is: ash calorific value * 1.16%. When the ash particle size is within the second threshold range, the formula for calculating the aluminum content in the ash is: ash calorific value * 1.35%.
[0027] Specifically, the aluminum content in the aluminum ash sample is the sum of the molten aluminum content and the aluminum content in the ash residue.
[0028] First, calculate the molten aluminum content using the formula: Molten aluminum content = Mass of aluminum block after melting and cooling / Mass of aluminum ash weighed.
[0029] Next, the aluminum content in the ash was calculated. The particle size of the cold ash was first determined. The particle size distribution of the cold ash was 0.15-0.425 mm. When the particle size of the cold ash was 0.425-2 mm, the metallic aluminum content in the cold ash = the measured calorific value * 1.16%; when the particle size of the cold ash was 0.15-0.425 mm, the metallic aluminum content in the cold ash = the measured calorific value * 1.35%.
[0030] Specifically, when the particle size of the cold ash slag is 0.425-2 mm, the measured calorific value of the furnace cold ash slag is 198-361 cal / g, and the aluminum nitride content is 2.37-5.76%; when the particle size of the cold ash slag is 0.15-0.425 mm, the measured calorific value of the furnace cold ash slag is 362-592 cal / g, and the aluminum nitride content is 0.33-2.36%.
[0031] The above technical solution will be further explained below through specific embodiments.
[0032] Example 1: This example provides a method for determining the aluminum recovery efficiency in aluminum ash. Specifically, the melting furnace is first heated to 750 °C at a heating rate of 30 °C / min. The aluminum-containing sample is a large, grayish-black sample. The aluminum-containing sample is crushed and sieved. After crushing, the particle size distribution of the aluminum ash is 0.15-2 mm. At this time, the moisture content of the sample is 0.97%, the AlN content is 10.13%, and the calorific value is 576 cal / g. 201.39 g of the crushed and sieved sample is weighed into the melting furnace heated to 750 °C for high-temperature melting and stirring at a stirring rate of 12 r / min for 6 min. After melting, the molten aluminum is poured into a dried iron container. After complete cooling, the mass of the aluminum block is weighed as 15.06 g. According to the calculation formula for molten Al content, the aluminum content of the sample is calculated to be 7.48%. The particle size of the cooled ash was measured to be 0.25 mm, the calorific value was measured to be 362 cal / g, and the AlN content was 0.36%. The aluminum content in the cooled ash was calculated to be 4.89%. At this point, the aluminum recovery efficiency was 12.37%.
[0033] Example 2: This example provides a method for determining the aluminum recovery efficiency in aluminum ash. Specifically, the melting furnace is first heated to 800 °C at a heating rate of 30 °C / min. The aluminum-containing sample is a large, grayish-black sample. The aluminum-containing sample is crushed and sieved. After crushing, the particle size distribution of the aluminum ash is 0.15-2 mm. The moisture content of the sample after sieving is 1.33%, the AlN content is 8.13%, and the calorific value is 767 cal / g. 212.87 g of the crushed and sieved sample is weighed into the melting furnace heated to 800 °C for high-temperature melting and stirring at a stirring rate of 10 r / min for 8 min. After melting, the molten aluminum is poured into a dried iron container. After complete cooling, the mass of the aluminum block is weighed as 21.52 g. The aluminum content of the sample is calculated to be 10.11% according to the formula for calculating the molten Al content. The particle size of the cooled ash was measured to be 0.36 mm, the calorific value was measured to be 297 cal / g, and the AlN content was 1.11%. The aluminum content in the cooled ash was calculated to be 4.01%, and the aluminum recovery efficiency was 14.12%.
[0034] Example 3: This example provides a method for determining the aluminum recovery efficiency in aluminum ash. Specifically, the melting furnace is first heated to 850 °C at a heating rate of 30 °C / min. The aluminum-containing sample is a fine gray sample. The aluminum-containing sample is crushed and sieved. The particle size distribution of the crushed aluminum ash is 0.15-2 mm. The moisture content of the sample after sieving is 0.97%, the AlN content is 7.99%, and the calorific value is 1072 cal / g. 210.77 g of the crushed and sieved sample is weighed into the melting furnace heated to 850 °C for high-temperature melting and stirring at a stirring rate of 14 r / min for 10 min. After melting, the molten aluminum is poured into a dried iron container. After complete cooling, the mass of the aluminum block is weighed as 30.50 g. The aluminum content of the sample is calculated to be 14.47% according to the formula for calculating the molten Al content. The particle size of the cooled ash was measured to be 0.425 mm, the calorific value was measured to be 592 cal / g, and the AlN content was 2.36%. The aluminum content in the cold ash was calculated to be 7.99%, and the aluminum recovery efficiency was 22.46%.
[0035] Example 4: This example provides a method for determining the aluminum recovery efficiency in aluminum ash. Specifically, the melting furnace is first heated to 900 °C at a heating rate of 30 °C / min. The aluminum-containing sample is a fine gray sample. The aluminum-containing sample is crushed and sieved. The particle size distribution of the crushed aluminum ash is 0.15-2 mm. The moisture content of the sample after sieving is 2.11%, the AlN content is 5.94%, and the calorific value is 1293 cal / g. 227.71 g of the crushed and sieved sample is weighed into the melting furnace heated to 900 °C for high-temperature melting and stirring at a stirring rate of 16 r / min for 10 min. After melting, the molten aluminum is poured into a dried iron container. After complete cooling, the mass of the aluminum block is weighed as 38.51 g. The aluminum content of the sample is calculated to be 14.28% according to the Al content calculation formula. The particle size of the cooled ash was measured to be 0.625 mm, the calorific value was measured to be 198 cal / g, and the AlN content was 2.37%. The aluminum content in the cold ash was calculated to be 2.30%, and the aluminum recovery efficiency was 16.58%.
[0036] Example 5: This example provides a method for determining the aluminum recovery efficiency in aluminum ash. Specifically, the melting furnace is first heated to 850 °C at a heating rate of 30 °C / min. The aluminum-containing sample is a large, grayish-black sample. The aluminum-containing sample is crushed and sieved. After crushing, the particle size distribution of the aluminum ash is 0.15-2 mm. The moisture content of the sample after sieving is 2.73%, the AlN content is 3.98%, and the calorific value is 943 cal / g. 206.82 g of the crushed and sieved sample is weighed into the melting furnace heated to 850 °C for high-temperature melting and stirring at a stirring rate of 10 r / min for 12 min. After melting, the molten aluminum is poured into a dried iron container. After complete cooling, the mass of the aluminum block is weighed as 25.76 g. According to the Al content calculation formula, the aluminum content of the sample is calculated to be 12.46%. The particle size of the cooled ash was measured to be 2 mm, the calorific value was measured to be 361 cal / g, and the AlN content was 5.76%. The aluminum content in the cold ash was calculated to be 4.19%. At this point, the aluminum recovery efficiency was 16.65%.
[0037] Therefore, the technical solution of this application mainly uses hot melting and multiple factors such as calorific value to judge the content of metallic aluminum in aluminum ash, which can quickly assess the recovery efficiency of metallic aluminum in aluminum ash within one hour.
[0038] In addition to the above embodiments, the present invention may have other implementation methods; all technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by the present invention.
Claims
1. A method for determining the aluminum recovery efficiency in aluminum ash, characterized in that: include: The aluminum ash sample was crushed and sieved. Control the furnace temperature to the target temperature, weigh out the target mass of aluminum ash, add it to the furnace and stir continuously; After stirring, pour the molten aluminum obtained from the smelting into a dried iron tray, cool it, and then weigh it. The ash and slag in the smelting furnace are weighed, and their calorific value and particle size are determined. The aluminum content in the aluminum ash sample is calculated using the formula: Aluminum content in aluminum ash sample = Molten aluminum content + Aluminum content in ash residue; The formula for calculating the molten aluminum content is: Molten aluminum content = Mass of aluminum block after melting and cooling / Mass of aluminum ash weighed. When the ash particle size is within the first threshold range, the formula for calculating the aluminum content in the ash is: ash calorific value * 1.16%. When the ash particle size is within the second threshold range, the formula for calculating the aluminum content in the ash is: ash calorific value * 1.35%.
2. The method for determining the aluminum recovery efficiency in aluminum ash according to claim 1, characterized in that: The particle size of the pulverized aluminum ash sample is 0.15-2 mm.
3. The method for determining the aluminum recovery efficiency in aluminum ash according to claim 1, characterized in that: The heating rate of the smelting furnace is 30℃ / min.
4. The method for determining the aluminum recovery efficiency in aluminum ash according to claim 1, characterized in that: The target temperature of the smelting furnace is 750-900 ℃.
5. The method for determining the aluminum recovery efficiency in aluminum ash according to claim 1, characterized in that: The target mass of the aluminum ash is 200-250g.
6. The method for determining the aluminum recovery efficiency in aluminum ash according to claim 1, characterized in that: The stirring time for the aluminum ash in the smelting furnace is 10-15 min.
7. The method for determining the aluminum recovery efficiency in aluminum ash according to claim 1, characterized in that: The drying temperature of the iron tray is 105℃, and the drying time is 1.5-3 hours.
8. The method for determining the aluminum recovery efficiency in aluminum ash according to claim 1, characterized in that: The first threshold range for the particle size of the ash is 0.425-2 mm, and the second threshold range for the particle size of the ash is 0.15-0.425 mm.