Gold tailing unfired haydite and preparation method thereof

Abstract

The application discloses a kind of gold tailings unfired haydite and preparation method thereof, belong to solid waste recycling technical field, solve the technical problem of high sintering energy consumption in the process of preparing haydite by using gold tailings in prior art, solution is as follows: gold tailings unfired haydite includes unfired haydite matrix, alkali activator and water, its weight fraction is as follows: unfired haydite matrix: gold tailings powder 15-30 parts, sludge 15-40 parts, fly ash 40-60 parts;Alkali activator: 10%-15% of the total weight of unfired haydite matrix;Water: 18%-25% of the total weight of unfired haydite matrix.The preparation method is as follows: gold tailings, sludge, fly ash and alkali activator are made into raw material ball, then constant temperature and humidity curing for a specific time to obtain unfired haydite.The gold tailings unfired haydite prepared by the application has the advantages of high compressive strength, low water absorption and simple operation, and realizes the comprehensive utilization of gold tailings, sludge and fly ash.

Description

Technical Field

[0001] This invention belongs to the field of solid waste recycling technology, specifically relating to a non-fired ceramsite for gold tailings and its preparation method. Background Technology

[0002] Tailings are a byproduct of ore beneficiation. With technological advancements and improved mining practices, mineral resources are being utilized on a large scale, resulting in a significant increase in tailings production. Although tailings disposal has long been a concern, the amount processed is far less than the growth in solid waste. The accumulation of large amounts of tailings not only wastes resources but also pollutes the environment.

[0003] Fly ash is a fine particle that is discharged from the flue gas duct and collected after the inorganic minerals in the raw materials undergo a series of physicochemical changes, such as burning, transformation, melting, and cooling, following the high-temperature combustion of pulverized coal or coal slime in the furnace. Although the utilization rate of fly ash has reached over 70%, the amount of fly ash remaining in stockpiles is still quite large due to years of accumulation.

[0004] Urban sewage is a byproduct of residents' necessary production and daily life. With the deepening of urbanization, the amount of sewage is increasing rapidly. After sewage treatment plants process it, a large amount of sludge is generated. If this sludge is not treated in a timely and effective manner, it will accumulate in large quantities and cause environmental pollution.

[0005] Currently published patent documents describe the use of gold tailings as ceramsite as follows: One or more of the following—red mud with pH > 9, iron tailings powder, carbide slag, and lithium slag—or a mixture of gold tailings and mineral powder, are used as the core and the outer wall of the ceramsite surrounding the core (Publication No.: CN 115321931 A); Gold tailings are mixed with industrial waste to form pellets, which are then mineralized and cured to obtain non-fired ceramsite (Publication No.: CN 116903302 A); Gold tailings, cement, and quicklime are mixed to form pellets, which are then autoclaved and cured, and finally impregnated with a waterproof coating to obtain non-fired lightweight ceramsite (Publication No.: CN 114804797 A). While creating the outer wall of the ceramsite or impregnating it with a waterproof coating can improve its performance, these methods increase the number of steps and make the process complex and time-consuming. Summary of the Invention

[0006] The main objective of this 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 using gold tailings. This invention provides a non-fired ceramsite made from gold tailings and its preparation method, which mixes gold tailings, urban sludge, and fly ash to prepare non-fired ceramsite, thereby making use of waste and playing a role in resource conservation and environmental protection.

[0007] This invention is achieved through the following technical solution: a non-fired ceramsite for gold tailings, wherein: the non-fired ceramsite for gold tailings comprises a non-fired ceramsite matrix, an alkali activator, and water, in the following weight proportions: Non-fired ceramsite matrix: 15-30 parts gold tailings powder, 15-40 parts sludge, and 40-60 parts fly ash; the total amount of fly ash and sludge added is higher than that of gold tailings. Fly ash can produce a pozzolanic effect under alkaline conditions, which can enhance the strength of ceramsite. The addition of sludge can reduce the bulk density. Alkali activator: 10%-15% of the total weight of the non-fired ceramsite matrix; Water: 18%-25% of the total weight of the non-fired 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 no greater than 100 mesh.

[0011] A method for preparing non-fired ceramsite from gold tailings as described above includes the following steps: S1. Weigh the raw materials according to the weight proportions of gold tailings powder, sludge and fly ash, mix them evenly and then prepare the non-fired ceramsite matrix. S2. Weigh the alkali activator and water according to the weight of the non-fired ceramsite matrix. Mix the alkali activator with the non-fired ceramsite matrix and then add water and stir until uniform to obtain the mixture. S3. Take 2g of the mixture prepared in step S2 each time and knead it into balls by hand to obtain a number of raw material balls; S4. The raw material pellets prepared in step S3 are left 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: curing temperature of 60℃ and curing humidity of 80%, to obtain gold tailings non-fired ceramsite.

[0012] The beneficial effects of this invention are as follows: 1. This invention adds an alkaline activator to a mixture of dry materials, including gold tailings, sludge, and fly ash, thereby placing the raw materials in an alkaline environment, allowing the ceramsite to achieve good performance even without firing. 2. This invention utilizes three solid wastes: gold tailings, sludge, and fly ash, with only a small amount of alkali activator added. The formulation is simple and easy to produce. In addition, this invention uses a non-sintering process to prepare ceramsite, which saves energy, reduces the emission of carbon and sulfur oxides, and will not cause secondary pollution to the environment. 3. This invention can effectively solve the ecological problems caused by the stockpiling of gold tailings, sludge, and fly ash. It is feasible and operable to use gold tailings, sludge, and fly ash to prepare ceramsite, which can make use of various solid waste resources and has good economic benefits and social significance. Attached Figure Description

[0013] Figure 1 This is a flowchart of the preparation process of the present invention; Figure 2 XRD pattern of the gold tailings non-fired ceramsite prepared in Example 1; Figure 3 SEM image of the gold tailings non-fired ceramsite prepared in Example 1. Detailed Implementation

[0014] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

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

[0016] Example 1

[0017] like Figure 1 The method for preparing non-fired ceramsite from gold tailings as described above includes the following steps: S1. Weigh out 25g of gold tailings powder, 25g of sludge and 50g of fly ash respectively. The particle size of gold tailings powder, sludge and fly ash is no more than 100 mesh. The sludge is sludge dried at room temperature and ground. Mix them evenly to obtain non-fired ceramsite matrix. The total weight of non-fired ceramsite matrix is ​​100g. S2. Weigh 15g of alkali activator (15% of the total weight of the non-fired ceramsite matrix) and 20g of water (20% of the total weight of the non-fired ceramsite matrix). The alkali activator used in this example 1 is sodium hydroxide. Mix the alkali activator with the non-fired ceramsite matrix and then add water and stir until uniform to obtain a mixture. S3. Take 2g of the mixture prepared in step S2 each time and knead it into balls by hand to obtain a number of raw material balls; S4. The raw material pellets prepared in step S3 are left 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: curing temperature of 60℃ and curing humidity of 80%. Gold tailings non-fired ceramsite is obtained, and its properties are shown in Table 2 below.

[0018] The phase composition of the gold tailings non-fired ceramsite prepared in Example 1 was analyzed using XRD, such as... Figure 2As shown, the main phase of the gold tailings-based non-fired ceramsite is quartz, and diffraction peaks of tobermorite were also detected. Tobermorite possesses good thermal and mechanical stability and is an important building material. The microstructure of the gold tailings-based non-fired ceramsite prepared in Example 1 was analyzed using SEM, and the results are as follows: Figure 3 As shown. It can be seen that... Figure 3 The area marked "1" is an amorphous flocculent substance, which can be identified as calcium silicate hydrate gel (CSH). Figure 3 The area marked "2" shows a fibrous structure, which is the morphology of tobermulite, consistent with the XRD results. The CSH surrounding the tobermulite makes the structure of the gold tailings non-fired ceramsite prepared in Example 1 more excellent, and therefore also shows better compressive strength. Example 2

[0019] like Figure 1 The method for preparing non-fired ceramsite from gold tailings as described above includes the following steps: S1. Weigh out 16.7g of gold tailings powder, 33.3g of sludge and 50g of fly ash respectively. The sludge is dried at room temperature and ground. The particle size of the gold tailings powder, sludge and fly ash is no more than 100 mesh. Mix them evenly to obtain a non-fired ceramsite matrix. The total weight of the non-fired ceramsite matrix is ​​100g. S2. Weigh 10g of alkali activator (10% of the total weight of the non-fired ceramsite matrix) and 18g of water (18% of the total weight of the non-fired ceramsite matrix). In this Example 2, the alkali activator used is calcium oxide. After mixing the alkali activator with the non-fired ceramsite matrix, add water and stir until uniform to obtain a mixture. S3. Take 2g of the mixture prepared in step S2 each time and knead it into balls by hand to obtain a number of raw material balls; S4. The raw material pellets prepared in step S3 are left 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: curing temperature of 60℃ and curing humidity of 80%. Gold tailings non-fired ceramsite is obtained, and its properties are shown in Table 2 below. Example 3

[0020] like Figure 1 The method for preparing non-fired ceramsite from gold tailings as described above includes the following steps: S1. Weigh out 20g of gold tailings powder, 40g of sludge and 40g of fly ash respectively. The sludge is dried at room temperature and ground. The particle size of the gold tailings powder, sludge and fly ash is no more than 100 mesh. Mix them evenly to obtain a non-fired ceramsite matrix. The total weight of the non-fired ceramsite matrix is ​​100g. S2. Weigh 15g of alkali activator (10% of the total weight of the non-fired ceramsite matrix) and 25g of water (25% of the total weight of the non-fired ceramsite matrix). The alkali activator used in this Example 3 is sodium silicate. After mixing the alkali activator with the non-fired ceramsite matrix, add water and stir until uniform to obtain a mixture. S3. Take 2g of the mixture prepared in step S2 each time and knead it into balls by hand to obtain a number of raw material balls; S4. The raw material pellets prepared in step S3 are left 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: curing temperature of 60℃ and curing humidity of 80%. Gold tailings non-fired ceramsite is obtained, and its properties are shown in Table 2 below.

[0021] The performance of the gold tailings-based non-fired ceramsite prepared in Examples 1-3 was tested. The water absorption rate, apparent density, and bulk density of the gold tailings-based non-fired ceramsite were determined according to GB / T 17431.2-2010 "Lightweight Aggregates and Their Test Methods Part 2: Test Methods for Lightweight Aggregates". The compressive strength of individual ceramsite particles was tested using a universal testing machine. The results are shown in Table 2.

[0022]

[0023] As shown in Table 2, the gold tailings non-fired ceramsite prepared in Examples 1-3 all meet the performance requirements, and the compressive strength of the gold tailings non-fired ceramsite prepared in Example 1 is the best among the given examples.

[0024] In summary, the gold tailings non-fired ceramsite prepared by this invention is an environmentally friendly non-fired ceramsite that can realize the resource utilization of gold tailings, urban sludge and fly ash.

[0025] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for preparing non-fired ceramsite from gold tailings, characterized in that, Includes the following steps: S1. Weigh out 25g of gold tailings powder, 25g of sludge and 50g of fly ash respectively. The particle size of gold tailings powder, sludge and fly ash is no more than 100 mesh. The sludge is sludge dried at room temperature and ground. Mix them evenly to obtain non-fired ceramsite matrix. The total weight of non-fired ceramsite matrix is ​​100g. S2. Weigh 15g of alkali activator and 20g of water. The alkali activator is sodium hydroxide. Mix the alkali activator with the non-fired ceramsite matrix, add water and stir until uniform to obtain the mixture. S3. Take 2g of the mixture prepared in step S2 each time and knead it into balls by hand to obtain a number of raw material balls; S4. The raw material pellets prepared in step S3 are left 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: curing temperature of 60℃ and curing humidity of 80%, to obtain gold tailings non-fired ceramsite with a bulk density of 727 kg / m³. 3 The apparent density is 1545 kg / m³. 3 The water absorption rate is 13.57% and the compressive strength is 2.68 MPa. In the microstructure of the gold tailings non-fired ceramsite, the hydrated calcium silicate gel is amorphous flocculent, the morphology of tobermulite is fibrous, and the hydrated calcium silicate gel is wrapped around the tobermulite.

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