Gold tailing unfired ceramsite and preparation method thereof

Abstract

The invention relates to gold tailing unfired ceramsite and a preparation method thereof, belongs to the technical field of solid waste recycling, and solves the technical problem of high sintering energy consumption in the process of preparing ceramsite from gold tailings in the prior art. The unfired ceramsite matrix comprises the following components in parts by weight: 15-30 parts of gold tailing powder, 15-40 parts of sludge and 40-60 parts of fly ash; the alkali activator accounts for 10%-15% of the total weight of the unfired ceramsite matrix; the weight of the water accounts for 18%-25% of the total weight of the unfired ceramsite matrix. The preparation method comprises the following steps: preparing raw material balls from the gold tailings, the sludge, the fly ash and the alkali activator, and then performing constant-temperature and constant-humidity maintenance for a specific time to obtain the unfired ceramsite. The gold tailing unfired ceramsite prepared by the method has the advantages of high compressive strength, low water absorption and simplicity in operation, and comprehensive utilization of the gold tailings, the sludge and the fly ash is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of solid waste recycling, and particularly relates to a gold tailings unburned ceramsite and a preparation method thereof. Background Art

[0002] Tailings are the product of ore dressing. With the advancement of science and technology, the level of mining resource development has been continuously improved, and mineral resources have been used in large quantities. At the same time, the output of tailings cannot be underestimated. Although the problem of tailings treatment has long been in the public eye, the treatment volume is far less than the growth of solid waste. The accumulation of a large amount of tailings not only wastes resources, but also causes environmental pollution.

[0003] Fly ash is fine particles that are discharged from the flue gas duct and collected after the inorganic minerals in the raw materials undergo a series of physical and chemical changes such as burning, conversion, melting, and cooling after coal powder or coal slime is burned at high temperature in the furnace. Although the utilization rate of fly ash has reached more than 70%, the stockpile surplus of fly ash is still large due to years of accumulation.

[0004] Urban sewage is the product of residents' necessary production and life. With the deepening of urbanization, the output of sewage is increasing rapidly. After sewage treatment plants treat it, a large amount of sludge will be produced. This sludge cannot be treated in a timely and effective manner and will accumulate in large quantities, causing pollution to the environment.

[0005] In the currently disclosed patent documents, the use of gold tailings as ceramsite is as follows: using red mud with pH>9, iron tailings powder, carbide slag and lithium slag, one or more of gold tailings and ore powder as the core and the outer wall of ceramsite wrapped on the outer surface of the core (publication number: CN 115321931 A); mixing gold tailings with industrial waste slag to make balls and then mineralizing and curing to obtain unburned ceramsite (publication number: CN 116903302 A); mixing gold tailings, cement and quicklime to make balls and then autoclaving and curing, and then soaking in waterproof coating to obtain unburned lightweight ceramsite (publication number: CN 114804797 A). Making the outer wall of ceramsite or soaking in waterproof coating can improve the performance of ceramsite, but it increases the production steps, and the operation process is complicated and time-consuming. Summary of the invention

[0006] The main purpose of the present invention is to overcome the shortcomings of the prior art and solve the technical problem of high sintering energy consumption in the process of preparing ceramsite from gold tailings in the prior art. The present invention provides a gold tailings unfired ceramsite and a preparation method thereof. Gold tailings, urban sludge and fly ash are mixed to prepare unfired ceramsite, thereby making use of waste and playing a role in resource conservation and environmental protection.

[0007] The present invention is achieved through the following technical scheme: a gold tailings unfired ceramsite, wherein: the gold tailings unfired ceramsite comprises an unfired ceramsite matrix, an alkali activator and water, and the weight proportions thereof are: Unburned ceramsite matrix: 15-30 parts of gold tailings powder, 15-40 parts of sludge, and 40-60 parts of fly ash; the total amount of fly ash and sludge added is higher than the amount of gold tailings added. Fly ash can produce volcanic ash effect under alkaline conditions, which plays a role in enhancing the strength of ceramsite, and the addition of sludge plays a role in reducing the bulk density; Alkali activator: 10%-15% of the total weight of the unfired ceramsite matrix; Water: 18%-25% of the total weight of the unfired ceramsite matrix.

[0008] Furthermore, the alkaline activator is one or more of sodium hydroxide, calcium oxide, and sodium silicate.

[0009] Furthermore, the sludge is sludge that has been dried and ground at room temperature.

[0010] Furthermore, the particle size of the gold tailings powder, sludge and fly ash is not greater than 100 mesh.

[0011] A method for preparing the gold tailings unburned ceramsite as described above comprises the following steps: S1. Weigh the raw materials according to the weight proportions of gold tailings powder, sludge and fly ash, and mix them evenly to obtain an unfired ceramsite matrix; S2, weighing an alkali activator and water according to the weight of the unfired ceramsite matrix, mixing the alkali activator with the unfired ceramsite matrix, adding water and stirring until uniform, to obtain a mixture; S3, taking 2 g of the mixture prepared in step S2 and kneading it into balls manually to obtain a number of raw material balls; S4. The raw material balls prepared in step S3 are allowed to stand at room temperature for 12 hours, and then placed in a constant temperature and humidity chamber for curing for 24 hours. The curing conditions are: the curing temperature is 60° C., and the curing humidity is 80%, to obtain gold tailings unfired ceramsite.

[0012] The beneficial effects of the present invention are: 1. The present invention adds an alkali activator to the mixed dry material of gold tailings, sludge and fly ash, so that the raw materials are in an alkaline environment, and the ceramsite can still achieve good performance without burning; 2. The present invention utilizes three solid wastes, namely gold tailings, sludge and fly ash, and only adds a small amount of alkali activator, so the ratio is simple and easy to make. In addition, the present invention adopts a sintering-free process to prepare ceramsite, which saves energy, reduces the emission of carbon and sulfur oxides, and does not cause secondary pollution to the environment. 3. The present invention can effectively solve the ecological problems caused by the storage of gold tailings, sludge and fly ash, and use gold tailings, sludge and fly ash to prepare expanded clay, which is feasible and operable, and can utilize a variety of solid waste resources, with good economic benefits and social significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The present invention is a process flow chart for preparing the same; Figure 2 The XRD pattern of the gold tailings unfired ceramsite prepared in Example 1; Figure 3 This is the SEM image of the unburned ceramsite from gold tailings prepared in Example 1. DETAILED DESCRIPTION

[0014] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0015] The chemical composition of the gold tailings used in the following examples is shown in Table 1.

[0016] Example 1

[0017] like Figure 1 The method for preparing the gold tailings unburned ceramsite as described above comprises the following steps: S1. Weigh 25g of gold tailings powder, 25g of sludge and 50g of fly ash respectively. The particle sizes of the gold tailings powder, sludge and fly ash are not greater than 100 meshes. The sludge is sludge dried and ground at room temperature. Mix them evenly to obtain an unfired ceramsite matrix. The total weight of the unfired ceramsite matrix is ​​100g. S2, weighing 15g of an alkaline activator (15% of the total weight of the unfired ceramsite matrix) and 20g of water (20% of the total weight of the unfired ceramsite matrix), wherein the alkaline activator used in this embodiment 1 is sodium hydroxide, mixing the alkaline activator with the unfired ceramsite matrix, adding water and stirring until uniform, to obtain a mixture; S3, taking 2 g of the mixture prepared in step S2 and kneading it into balls manually to obtain a number of raw material balls; S4. The raw material balls prepared in step S3 were allowed to stand at room temperature for 12 hours, and then placed in a constant temperature and humidity chamber for curing for 24 hours. The curing conditions were: the curing temperature was 60° C., and the curing humidity was 80%. The gold tailings unfired ceramsite was obtained, and its properties were shown in Table 2 below.

[0018] The physical phase of the gold tailings unfired ceramsite prepared in Example 1 was analyzed by XRD. Figure 2As shown in Figure 1, the main phase of the gold tailings unfired ceramsite is quartz, and the diffraction peak of tobermorite is also detected. Tobermorite has good thermal stability and mechanical stability and is an important building material. The microscopic morphology of the gold tailings unfired ceramsite prepared in Example 1 was analyzed by SEM, and the results are as follows: Figure 3 As shown. Figure 3 The position marked "1" in the figure is amorphous and flocculent, which can be identified as calcium silicate hydrate gel (CSH). Figure 3 The position marked "2" in the middle is fibrous, which is the morphology of Tobermorite, consistent with the XRD result. CSH is wrapped around Tobermorite, making the gold tailings unburned ceramsite structure prepared in Example 1 more excellent, and thus also showing better compressive strength. Example 2

[0019] like Figure 1 The method for preparing the gold tailings unburned ceramsite as described above comprises the following steps: S1. Weigh 16.7 g of gold tailings powder, 33.3 g of sludge and 50 g of fly ash respectively, wherein the sludge is dried and ground at room temperature, and the particle size of the gold tailings powder, sludge and fly ash is not greater than 100 meshes, and mix them evenly to obtain an unfired ceramsite matrix, and the total weight of the unfired ceramsite matrix is ​​100 g; S2, weighing 10g of alkaline activator (10% of the total weight of the unfired ceramsite matrix) and 18g of water (18% of the total weight of the unfired ceramsite matrix), the alkaline activator used in this embodiment 2 is calcium oxide, mixing the alkaline activator with the unfired ceramsite matrix, adding water and stirring until uniform, to obtain a mixture; S3, taking 2 g of the mixture prepared in step S2 and kneading it into balls manually to obtain a number of raw material balls; S4. The raw material balls prepared in step S3 were allowed to stand at room temperature for 12 hours, and then placed in a constant temperature and humidity chamber for curing for 24 hours. The curing conditions were: the curing temperature was 60° C., and the curing humidity was 80%. The gold tailings unfired ceramsite was obtained, and its properties were shown in Table 2 below. Example 3

[0020] like Figure 1 The method for preparing the gold tailings unburned ceramsite as described above comprises the following steps: S1. Weigh 20g of gold tailings powder, 40g of sludge and 40g of fly ash respectively, wherein the sludge is dried and ground at room temperature, and the particle sizes of the gold tailings powder, sludge and fly ash are not greater than 100 meshes, and mix them evenly to obtain an unfired ceramsite matrix, and the total weight of the unfired ceramsite matrix is ​​100g; S2, weighing 15g of an alkali activator (10% of the total weight of the unfired ceramsite matrix) and 25g of water (25% of the total weight of the unfired ceramsite matrix), wherein the alkali activator used in Example 3 is sodium silicate, mixing the alkali activator with the unfired ceramsite matrix, adding water and stirring until uniform, to obtain a mixture; S3, taking 2 g of the mixture prepared in step S2 and kneading it into balls manually to obtain a number of raw material balls; S4. The raw material balls prepared in step S3 were allowed to stand at room temperature for 12 hours, and then placed in a constant temperature and humidity chamber for curing for 24 hours. The curing conditions were: the curing temperature was 60° C., and the curing humidity was 80%. The gold tailings unfired ceramsite was obtained, and its properties were shown in Table 2 below.

[0021] The performance tests were conducted on the gold tailings unburned ceramsite prepared in Examples 1 to 3. The water absorption rate, apparent density, and bulk density of the gold tailings unburned ceramsite were measured in accordance with GB / T 17431.2-2010 "Lightweight aggregates and their test methods Part 2: Lightweight aggregate test methods". The compressive strength of a single ceramsite was tested using a universal testing machine. The results are shown in Table 2.

[0022]

[0023] It can be seen from Table 2 that the gold tailings unfired ceramsite prepared in Examples 1-3 all meet the performance requirements, and the compressive strength of the gold tailings unfired ceramsite prepared in Example 1 is the best among all the given examples.

[0024] In summary, the gold tailings unburned ceramsite prepared by the present invention is an environmentally friendly unburned ceramsite, which can realize the resource utilization of gold tailings, urban sludge and fly ash.

[0025] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A gold tailings unburned ceramsite, characterized in that: The gold tailings unburned ceramsite comprises an unburned ceramsite matrix, an alkali activator and water, and the weight proportions thereof are: Unburned ceramsite matrix: 15-30 parts of gold tailings powder, 15-40 parts of sludge, 40-60 parts of fly ash; Alkali activator: 10%-15% of the total weight of the unfired ceramsite matrix; Water: 18%-25% of the total weight of the unfired ceramsite matrix.

2. The gold tailings unburned ceramsite according to claim 1, characterized in that: The alkaline activator is one or more of sodium hydroxide, calcium oxide and sodium silicate.

3. The gold tailings unburned ceramsite according to claim 1, characterized in that: The sludge is room temperature dried and ground sludge.

4. The gold tailings unburned ceramsite according to claim 1, characterized in that: The particle size of the gold tailings powder, sludge and fly ash is no more than 100 meshes.

5. A method for preparing the unburned ceramsite of gold tailings as claimed in claim 1, characterized in that: The following steps are involved: S1. Weigh the raw materials according to the weight proportions of gold tailings powder, sludge and fly ash, and mix them evenly to obtain an unfired ceramsite matrix; S2, weighing an alkali activator and water according to the weight of the unfired ceramsite matrix, mixing the alkali activator with the unfired ceramsite matrix, adding water and stirring until uniform, to obtain a mixture; S3, taking 2 g of the mixture prepared in step S2 and kneading it into balls manually to obtain a number of raw material balls; S4. The raw material balls prepared in step S3 are allowed to stand at room temperature for 12 hours, and then placed in a constant temperature and humidity chamber for curing for 24 hours. The curing conditions are: the curing temperature is 60° C., and the curing humidity is 80%, to obtain gold tailings unfired ceramsite.

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