Rapid detection method for soluble salt in red mud material

Abstract

The invention relates to the technical field of red mud scumming detection, and discloses a rapid detection method for soluble salts in a red mud material, which comprises the following steps: S1, sample crushing and screening: crushing a red mud material sample, drying, and screening to obtain a screen underflow; s2, stirring and soaking the sample: adding the screen underflow into purified water, stirring, standing, and taking supernate; s3, absorption of supernate: dropping the supernate onto black cotton cloth; s4, blooming phenomenon detection: after the black pure cotton cloth is dried, observing whether white frost is separated out on the surface of the black cotton cloth or not; therefore, whether soluble salt exists in the red mud material sample or not is judged, and the scumming phenomenon of a product prepared from the red mud material is obtained. According to the method, whether the red mud contains the soluble salt or not can be rapidly detected, the detection means is simple, the detection result is accurate, no extra reagent needs to be added, only the sample needs to be crushed, sieved and soaked, the input cost is low, the detection process time is short, and the method has wide popularization and application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of red mud bloom detection, in particular to a rapid detection method for soluble salts in red mud materials. Background Art

[0002] Red mud is a highly alkaline red mud-like industrial waste produced during the production of industrial alumina. Every ton of alumina produced will produce about 1 to 2 tons of red mud. With the rapid development of my country's industry, a large amount of red mud is disposed of in the form of storage yards. It not only occupies land, but the alkaline salts and other harmful elements in the red mud, such as heavy metals and radioactive substances, have caused serious harm to the environment around the storage yards, and also posed a serious threat to the health of the surrounding people. Therefore, research on the resource utilization of red mud is of great significance.

[0003] Red mud contains a lot of Al and Si materials and is a potential raw material for construction. At present, the large-scale resource utilization of red mud is mainly concentrated in building materials. The soluble alkali salts (mainly Na+ and K+ salts) in red mud mainly exist in the red mud liquid phase and mineral surface. Under the action of dissolution reaction and evaporation, they are easy to migrate to the surface of red mud, which leads to the occurrence of frosting. Due to the high alkalinity and high soluble salt content of red mud, the frosting problem of its resource utilization products has existed for a long time. At the same time, the frosting phenomenon has a serious impact on the appearance and performance of red mud resource utilization products. The frosting problem has seriously hindered the resource utilization process of red mud. Therefore, it is necessary to detect the frosting problem of red mud. However, at this stage, there is a lack of detection methods and specifications for red mud frosting. Summary of the invention

[0004] The object of the present invention is to provide a method for quickly detecting soluble salts in red mud materials to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for rapid detection of soluble salts in red mud material comprises the following steps:

[0007] S1. Sample crushing and screening: 1000 to 2000 parts of red mud material samples are taken by mass, crushed and placed in a constant temperature blast drying oven, dried to constant weight, and then passed through a 100-mesh test sieve to obtain the sieve-under material for later use;

[0008] S2. Sample stirring and soaking: Take 10-15 parts of the sieve and place them in a beaker; then take 20-30 parts of clean water and add it to the beaker; stir with a stirring rod, let it stand, and take the supernatant. Using clean water can avoid the interference of foreign soluble salts on the experimental results;

[0009] S3. Absorption of supernatant: Spread black pure cotton cloth on the tray, use a rubber-tipped dropper to absorb 0.05 parts of the supernatant, and drop it to the middle of the black cotton cloth, so that the supernatant is completely absorbed by the black pure cotton cloth. Since the color of the frosting phenomenon is mainly white, the use of black cotton cloth can highlight the frosting phenomenon. The area of ​​the black pure cotton should be smaller than the area of ​​the tray. For example, the size of the black pure cotton cloth is 10 cm × 10 cm, and the size of the tray is 18 cm × 13 cm.

[0010] S4. Frosting phenomenon detection: Put the tray together with the black pure cotton cloth into the drying oven for drying. At this temperature, the black cotton cloth can be dried faster and will not affect the experimental process. After the moisture in the black pure cotton cloth is completely dried, observe whether there is white frost on the surface of the black cotton cloth; if white frost is precipitated, it proves that there are soluble salts in the red mud material sample, which may cause frosting in the product prepared from the red mud material, and the concentration of soluble salts can be judged by the depth of the white frost color; if no white frost is precipitated, it proves that there are no soluble salts in the red mud material sample, and will not cause frosting in the product prepared from the red mud material.

[0011] As a further solution of the present invention: in the step S1, the red mud material sample includes an original red mud material sample, a pretreated red mud material sample, and a product sample made of red mud material.

[0012] As a further solution of the present invention: in the step S1, the drying temperature is 45-65°C, and the particle size of the sieved material is not greater than 0.15 mm.

[0013] As a further solution of the present invention: in the step S2, the purified water is one of deionized water, distilled water or ultrapure water.

[0014] As a further solution of the present invention: in the step S2, the stirring time is 3 to 5 minutes and the standing time is 8 to 12 hours.

[0015] As a further solution of the present invention: in the step S4, the drying temperature is 50-65°C and the drying time is 25-40 minutes.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The method comprises the following steps: firstly crushing and screening the red mud material sample, and then adding the sieved material into clean water; after stirring, standing, and then dropping the supernatant onto a black pure cotton cloth; after drying, observing whether white frost is precipitated on the surface of the black cotton cloth; the method can quickly detect whether the red mud contains soluble salt, and the detection means are simple, the detection result is accurate, and no additional reagents need to be added. Only the sample needs to be crushed, screened, and soaked, and the investment cost is low, the detection process time is short, and the method has a wide prospect for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a schematic diagram of a process for rapid detection of soluble salts in red mud materials. DETAILED DESCRIPTION

[0019] Example 1

[0020] In an embodiment of the present invention, a method for rapid detection of soluble salts in red mud material comprises the following steps:

[0021] S1. Sample crushing and screening: Take 1000 parts of red mud material samples by mass, crush the red mud material samples and put them into a constant temperature blast drying oven, dry them at 45°C to constant weight, and then pass them through a 100-mesh test sieve to obtain the sieve-undersized material with a particle size of no more than 0.15 mm for use;

[0022] S2. Sample stirring and soaking: Take 10 parts of the sieve and place them in a beaker; then take 20 parts of deionized water and add them to the beaker; stir with a stirring rod for 3 minutes, let it stand for 12 hours, and take the supernatant;

[0023] S3. Absorption of supernatant: Spread black pure cotton cloth on a tray, use a rubber-tipped dropper to absorb 0.05 parts of the supernatant, and drop it to the middle of the black cotton cloth, so that the supernatant is completely absorbed by the black pure cotton cloth;

[0024] S4. Detection of frosting: Place the tray together with the black pure cotton cloth in a drying oven and dry at 50°C for 40 minutes. After the moisture in the black pure cotton cloth is completely dried, observe whether there is white frost on the surface of the black cotton cloth. If there is white frost, it proves that there are soluble salts in the red mud material sample, which may cause frosting in the product prepared from the red mud material, and the concentration of soluble salts can be judged by the depth of the white frost color. If there is no white frost, it proves that there are no soluble salts in the red mud material sample, and the product prepared from the red mud material will not cause frosting.

[0025] Example 2

[0026] In an embodiment of the present invention, a method for rapid detection of soluble salts in red mud material comprises the following steps:

[0027] S1. Sample crushing and screening: 1500 parts of red mud material samples were taken by mass, crushed and placed in a constant temperature blast drying oven, dried at 55°C to constant weight, and then passed through a 100-mesh test sieve to obtain the sieve material with a particle size of no more than 0.15 mm for later use;

[0028] S2. Sample stirring and soaking: Take 12 parts of the sieve and place them in a beaker; then take 25 parts of distilled water and add them to the beaker; stir with a stirring rod for 4 minutes, let it stand for 10 hours, and take the supernatant;

[0029] S3. Absorption of supernatant: Spread black pure cotton cloth on a tray, use a rubber-tipped dropper to absorb 0.05 parts of the supernatant, and drop it to the middle of the black cotton cloth, so that the supernatant is completely absorbed by the black pure cotton cloth;

[0030] S4. Detection of frosting: Place the tray together with the black pure cotton cloth into a drying oven and dry at 58°C for 32 minutes. After the moisture in the black pure cotton cloth is completely dried, observe whether there is white frost on the surface of the black cotton cloth. If there is white frost, it proves that there are soluble salts in the red mud material sample, which may cause frosting in the product prepared from the red mud material, and the concentration of soluble salts can be judged by the depth of the white frost color. If there is no white frost, it proves that there are no soluble salts in the red mud material sample, and the product prepared from the red mud material will not cause frosting.

[0031] Example 3

[0032] In an embodiment of the present invention, a method for rapid detection of soluble salts in red mud material comprises the following steps:

[0033] S1. Sample crushing and screening: Take 2000 parts of red mud material samples by mass, crush the red mud material samples and put them into a constant temperature blast drying oven, dry them at 65°C to constant weight, and then pass them through a 100-mesh test sieve to obtain the sieve-undersized material with a particle size of no more than 0.15 mm for use;

[0034] S2. Sample stirring and soaking: Take 15 parts of the sieve and place them in a beaker; then take 30 parts of ultrapure water and add them to the beaker; stir with a stirring rod for 5 minutes, let it stand for 8 hours, and take the supernatant;

[0035] S3. Absorption of supernatant: Spread black pure cotton cloth on a tray, use a rubber-tipped dropper to absorb 0.05 parts of the supernatant, and drop it to the middle of the black cotton cloth, so that the supernatant is completely absorbed by the black pure cotton cloth;

[0036] S4. Detection of frosting: Place the tray together with the black pure cotton cloth into a drying oven and dry at 65°C for 25 minutes. After the moisture in the black pure cotton cloth is completely dried, observe whether there is white frost on the surface of the black cotton cloth. If there is white frost, it proves that there are soluble salts in the red mud material sample, which may cause frosting in the product prepared from the red mud material, and the concentration of soluble salts can be judged by the depth of the white frost color. If there is no white frost, it proves that there are no soluble salts in the red mud material sample, and the product prepared from the red mud material will not cause frosting.

[0037] In order to better illustrate the technical effect of the present invention, the following experiments are used to illustrate:

[0038] Taking the Bayer red mud of XXX aluminum plant of Aluminum Corporation of China as an example, the red mud was divided into three groups, one of which was not treated; the second group was washed with clean water for 3 times; the third group was soaked in weak acid for 24 hours; and then the content of Na+ and K+ in the three groups of red mud was detected by atomic absorption spectrophotometer respectively;

[0039] After testing, it was found that the Na+ content in group one of red mud was 2.55%, and the K+ content was 1.18%; the Na+ content in group two of red mud was 0.72%, and the K+ content was 0.44%; the Na+ content in group three of red mud was 0.13%, and the K+ content was 0.07%.

[0040] The red mud in the three groups was used as red mud material samples, and the soluble salt of the three groups of red mud was tested by the methods of Examples 1 to 3. The test results showed that:

[0041] For a group of red mud as red mud material samples: a large amount of white frost is precipitated on the surface of the black cotton cloth in the methods of Examples 1 to 3; therefore, a large amount of soluble salts exist in the red mud material samples, which is consistent with the results of atomic absorption spectrophotometer detection, that is, the Na+ content in the group of red mud is 2.55%, and the K+ content is 1.18%;

[0042] For the two groups of red mud as red mud material samples: a small amount of white frost is precipitated on the surface of the black cotton cloth in the methods of Examples 1 to 3; therefore, a small amount of soluble salt exists in the red mud material sample, which is consistent with the result of detection by atomic absorption spectrophotometer, that is, the Na+ content in the two groups of red mud is 0.72%, and the K+ content is 0.44%;

[0043] For the three groups of red mud as red mud material samples: the black cotton cloth surfaces in the methods of Examples 1 to 3 had almost no white frost precipitation; therefore, there was almost no soluble salt in the red mud material samples, which was consistent with the results of atomic absorption spectrophotometer detection, that is, the Na+ content in the three groups of red mud was 0.13%, and the K+ content was 0.07%;

[0044] It can be further concluded that the method adopted by the present invention can quickly detect the soluble salt in red mud, and the detection means are simple, the detection results are accurate, no additional reagents need to be added, and only the sample needs to be crushed, screened, and soaked. The investment cost is low, the detection process time is short, and it has broad promotion and application prospects.

[0045] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A rapid detection method for soluble salts in red mud material, characterized in that: The following steps are involved: S1. Sample crushing and screening: 1000 to 2000 parts of red mud material samples are taken by mass, crushed and placed in a constant temperature blast drying oven, dried to constant weight, and then passed through a 100-mesh test sieve to obtain the sieve-under material for later use; S2. Sample stirring and soaking: Take 10-15 parts of the sieve and place them in a beaker; then take 20-30 parts of clean water and add it to the beaker; stir with a stirring rod, let it stand, and take the supernatant; S3. Absorption of supernatant: Spread black pure cotton cloth on a tray, use a rubber-tipped dropper to absorb 0.05 parts of the supernatant, and drop it to the middle of the black cotton cloth, so that the supernatant is completely absorbed by the black pure cotton cloth; S4. Frosting detection: Put the tray together with the black pure cotton cloth into the drying oven to dry. After the moisture in the black pure cotton cloth is completely dried, observe whether there is white frost on the surface of the black cotton cloth; if there is white frost, it proves that there are soluble salts in the red mud material sample, which may cause frosting in the products prepared from the red mud material, and the concentration of soluble salts can be judged by the depth of the white frost color; if there is no white frost, it proves that there are no soluble salts in the red mud material sample, and will not cause frosting in the products prepared from the red mud material.

2. The method for rapid detection of soluble salts in red mud material according to claim 1, characterized in that: In the step S1, the red mud material samples include original red mud material samples, pretreated red mud material samples, and product samples made from red mud materials.

3. The method for rapid detection of soluble salts in red mud material according to claim 1, characterized in that: In the step S1, the drying temperature is 45-65°C, and the particle size of the sieved material is not greater than 0.15 mm.

4. The method for rapid detection of soluble salts in red mud material according to claim 1, characterized in that: In the step S2, the purified water is one of deionized water, distilled water or ultrapure water.

5. The method for rapid detection of soluble salts in red mud material according to claim 1, characterized in that: In the step S2, the stirring time is 3 to 5 minutes, and the standing time is 8 to 12 hours.

6. The method for rapid detection of soluble salts in red mud material according to claim 1, characterized in that: In the step S4, the drying temperature is 50-65° C., and the drying time is 25-40 minutes.

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