Method for preparing curing agent based on lithium slag

Abstract

The invention relates to the technical field of lithium slag, and discloses a method for preparing a curing agent based on lithium slag, which comprises the following preparation steps: 1) preparing a curing material, an additive and an alkali activator according to a ratio of (60-80): (10-30): (5-10); (2) a curing material, an additive and an alkali activator are placed in a stirrer, the curing material, the additive and the alkali activator are stirred and mixed, and a curing agent used for being mixed with the soft soil to cure the soft soil is formed; the lithium slag is used as a part of a curing material and has a synergistic effect with other materials such as Portland cement and sulphoaluminate cement, so that the gelling performance of the curing agent can be remarkably enhanced, the strength, durability and the like of the cured soft soil are greatly improved by optimizing the proportion through the synergistic effect, and thus a better soft soil curing effect is achieved.

Description

Technical Field

[0001] The patent of this invention relates to the technical field of lithium slag, specifically, to a method for preparing a curing agent based on lithium slag. Background Art

[0002] Lithium slag is a byproduct of lithium ore extraction, primarily from the extraction of lepidolite and spodumene. Its extremely fine particles offer high surface area and activity, but also present challenges in storage and handling.

[0003] The chemical composition of lithium slag is complex, containing a variety of metal oxides and silicates, and has potential gelling properties, making it suitable for the preparation of curing agent materials.

[0004] Existing soft soil curing methods primarily rely on traditional cement and other cementitious materials. While these can improve the strength of soft soil to a certain extent, the strength of the cured soft soil decreases significantly in high humidity and saline-alkali environments, resulting in insufficient durability. For example, traditional cement-based curing agents are prone to expansion and cracking under sulfate attack, leading to structural damage.

[0005] Different types of soft soil (such as high liquid limit soil, expansive soil, etc.) have different requirements for curing agents. Traditional curing agents are difficult to adapt to the diverse characteristics of soft soil. For example, high liquid limit soil requires a higher curing agent dosage to achieve the ideal curing effect. In addition, the performance stability of traditional curing agents under different environmental conditions is poor, and a lot of adjustments and optimizations are required according to specific working conditions. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for preparing a curing agent based on lithium slag, aiming to solve the problem of poor curing effect of soft soil in the prior art.

[0007] The present invention is achieved by a method for preparing a curing agent based on lithium slag, comprising the following preparation steps:

[0008] 1) preparing a curing material, an additive and an alkali activator, wherein the curing material includes silicate cement, sulfoaluminate cement, mineral powder, gypsum, fly ash, stone powder and lithium slag, the additive contains quicklime, and the alkali activator includes calcium carbonate and sodium hydroxide. The ratio of the curing material, the additive and the alkali activator is (60-80): (10-30): (5-10) by weight;

[0009] 2) The curing material, additives and alkali activator are placed in a mixer, and the mixer mixes the curing material, additives and alkali activator to form a curing agent for mixing with soft soil to solidify the soft soil.

[0010] Furthermore, in the preparation step 1), the silicate cement is of P·O42.5 grade, the mineral powder is of S95 or S105 grade, the gypsum includes desulfurized gypsum, anhydrite or hemihydrate gypsum, and the lithium slag is waste generated by the lithium salt extraction process.

[0011] Furthermore, in the preparation step 1), in terms of mass proportion, the silicate cement accounts for 10% to 40%, the sulfoaluminate cement accounts for 1% to 15%, the mineral powder accounts for 20% to 60%, the gypsum accounts for 10% to 30%, the fly ash accounts for 1% to 30%, the stone powder accounts for 1% to 10%, and the lithium slag accounts for 10% to 30%.

[0012] Furthermore, in the preparation step 1), the additive is white quicklime powder, and the purity of the additive is higher than 90%.

[0013] Furthermore, in the preparation step 1), the lithium slag is crushed by a crusher and then screened by a screening device.

[0014] Furthermore, in the preparation step 1), the screened lithium slag is dried with hot air in a hot air furnace to reduce the moisture content of the lithium slag to less than 2%.

[0015] Furthermore, in the preparation step 1), the hot blast furnace includes a combustion chamber and a drying chamber, the bottom of the drying chamber is connected to the combustion chamber through an air inlet pipe, the top of the drying chamber is provided with an air outlet pipe, and the air inlet pipe and the air outlet pipe are respectively provided with a restriction mesh layer, the restriction mesh layer has a mesh, and the diameter of the mesh is smaller than the particle size of the lithium slag;

[0016] When the temperature in the combustion chamber reaches the set temperature, the hot air in the combustion chamber passes through the air inlet pipe and is blown upward from the bottom of the drying chamber, blowing the lithium slag in the drying chamber upward into a suspended state, and the air in the drying chamber is discharged from the air outlet pipe.

[0017] Furthermore, in the preparation step 1), the bottom of the drying chamber has an air inlet, the air inlet is covered with a restrictive mesh layer, and the air inlet is connected to the air inlet pipe; a track ring is provided in the drying chamber, and the track ring surrounds the outer circumference of the air inlet;

[0018] The orbital ring is provided with a rotating ring, and the rotating ring is provided with a plurality of blades arranged obliquely, and the plurality of blades are arranged around the circumference of the rotating ring at intervals; the lower ends of the blades are docked on the rotating ring, and the upper ends of the blades are arranged obliquely toward the upper side of the air inlet, and the inclination angles of the plurality of blades are different;

[0019] In the preparation step 1), when the air inlet pipe blows hot air into the drying chamber from the bottom through the air inlet, the hot air drives the multiple blades to rotate the rotating ring relative to the track ring, and the multiple blades rotate synchronously with the rotating ring to make the hot air form a vortex.

[0020] Furthermore, in the preparation step 1), the dried lithium slag is ball-milled using a ball mill to form a powdered lithium slag powder having a specific surface area of ​​not less than 600 to 700 m 2 / g.

[0021] Compared with the prior art, the method for preparing a curing agent based on lithium slag provided by the present invention has the following advantages:

[0022] 1) By using lithium slag as part of the solidifying material and synergizing it with other materials such as silicate cement and sulphoaluminate cement, the gelling properties of the solidifying agent can be significantly enhanced. This synergistic effect can significantly improve the strength and durability of the solidified soft soil by optimizing the ratio (the ratio of the solidifying material, additive and alkali activator is (60-80): (10-30): (5-10)), thereby achieving a better soft soil solidification effect.

[0023] 2) By combining multiple materials, it can better adapt to different types of soft soil, allowing for flexible adjustments based on the specific characteristics of the soft soil, thereby improving the versatility and adaptability of the curing agent. For example, under different environmental conditions such as humidity and pH, the curing agent can maintain a stable curing effect, further enhancing its reliability and practicality in practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic flow chart of a method for preparing a curing agent based on lithium slag provided by the present invention;

[0025] Figure 2 It is a cross-sectional schematic diagram of the hot blast stove provided by the present invention;

[0026] In the figure: hot air furnace 100, combustion chamber 101, drying chamber 102, air outlet pipe 103, limiting mesh layer 104, air inlet pipe 200, air inlet 201, track ring 202, rotating ring 203, blades 204. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0028] The implementation of the present invention is described in detail below with reference to specific embodiments.

[0029] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0030] Reference Figure 1-2 The figure shows a preferred embodiment of the present invention.

[0031] The preparation method of the curing agent based on lithium slag comprises the following preparation steps:

[0032] 1) Prepare curing materials, additives and alkali activators, wherein the curing materials include silicate cement, sulfoaluminate cement, mineral powder, gypsum, fly ash, stone powder and lithium slag, the additives include quicklime, and the alkali activators include calcium carbonate and sodium hydroxide. The ratio of curing materials, additives and alkali activators is (60-80): (10-30): (5-10) by weight;

[0033] 2) Put the curing material, additives and alkali activator into a mixer, and mix the curing material, additives and alkali activator in the mixer to form a curing agent for mixing with soft soil to solidify the soft soil.

[0034] The above-mentioned method for preparing a curing agent based on lithium slag has the following advantages:

[0035] 1) By using lithium slag as part of the solidifying material and synergizing it with other materials such as silicate cement and sulphoaluminate cement, the gelling properties of the solidifying agent can be significantly enhanced. This synergistic effect can significantly improve the strength and durability of the solidified soft soil by optimizing the ratio (the ratio of the solidifying material, additive and alkali activator is (60-80): (10-30): (5-10)), thereby achieving a better soft soil solidification effect.

[0036] 2) By combining multiple materials, it can better adapt to different types of soft soil, allowing for flexible adjustments based on the specific characteristics of the soft soil, thereby improving the versatility and adaptability of the curing agent. For example, under different environmental conditions such as humidity and pH, the curing agent can maintain a stable curing effect, further enhancing its reliability and practicality in practical applications.

[0037] In this embodiment, in the preparation step 1), the silicate cement is of P·O42.5 grade, the mineral powder is of S95 or S105 grade, the gypsum includes desulfurized gypsum, anhydrite or hemihydrate gypsum, and the lithium slag is waste generated in the lithium salt extraction process.

[0038] The selection of P·O42.5 grade Portland cement ensures high strength and good hydration properties, providing a fundamental guarantee for the performance of the curing agent. The use of S95 or S105 grade mineral powder can effectively improve the density and durability of the curing agent. The selection of desulfurized gypsum, anhydrite, or hemihydrate gypsum as the gypsum component can fully utilize its role in regulating setting time. The introduction of lithium slag, a waste product from the lithium salt extraction process, not only realizes the resource utilization of waste and reduces costs, but also brings unique properties to the curing agent. Its fine particles can fill the pores of other materials, further enhancing the density and strength of the curing agent, thus providing strong support for better curing of soft soil.

[0039] In this embodiment, in the preparation step 1), in terms of mass proportion, silicate cement accounts for 10% to 40%, sulfoaluminate cement accounts for 1% to 15%, mineral powder accounts for 20% to 60%, gypsum accounts for 10% to 30%, fly ash accounts for 1% to 30%, stone powder accounts for 1% to 10%, and lithium slag accounts for 10% to 30%.

[0040] Through this specific mass ratio range, after careful design and optimization, a good synergistic effect can be formed between the components. The reasonable combination of silicate cement and sulphoaluminate cement takes into account the development of early strength and late strength. The addition of mineral powder, gypsum, fly ash, stone powder, etc. further optimizes the microstructure and performance of the curing agent, improves its compatibility with soft soil and the curing effect. Within this ratio range, lithium slag can give full play to its activity, interact with other components, form a stable curing system, effectively improve the mechanical properties and stability of soft soil, and provide a key guarantee for solving the problem of poor soft soil curing effect.

[0041] In this embodiment, in the preparation step 1), the additive is white quicklime powder, and the purity of the additive is higher than 90%. Thus, during the curing process, the quicklime reacts with water to form calcium hydroxide, which further participates in the curing reaction, increases the alkalinity of the curing agent, and promotes the hydration reaction of other components, thereby accelerating the curing process and enhancing the strength of the soft soil after curing, providing strong support for improving the soft soil curing effect.

[0042] In this embodiment, in the preparation step 1), the lithium slag is crushed by a crusher and then sieving by a screening device. In this way, the lithium slag after crushing and screening has a more moderate particle size, can be better mixed and reacted with other components, give full play to its role in the curing agent, and lay the foundation for improving the performance of the curing agent and the curing effect of soft soil.

[0043] In this embodiment, in preparation step 1), the screened lithium slag is dried with hot air in a hot air furnace 100 to reduce the moisture content of the lithium slag to less than 2%. This effectively removes moisture from the lithium slag, preventing it from introducing excessive moisture during subsequent preparation processes and affecting the performance of the curing agent. The lithium slag with a low moisture content can better interact with other components in the curing agent, improving the uniformity and stability of the curing agent, thereby further enhancing the curing effect of the soft soil.

[0044] In this embodiment, in the preparation step 1), the hot air furnace 100 includes a combustion chamber 101 and a drying chamber 102, the bottom of the drying chamber 102 is connected to the combustion chamber 101 through an air inlet pipe 200, and the top of the drying chamber 102 is provided with an air outlet pipe 103, and the air inlet pipe 200 and the air outlet pipe 103 are respectively provided with a restriction mesh layer 104, and the restriction mesh layer 104 has a mesh, and the diameter of the mesh is smaller than the particle size of the lithium slag;

[0045] When the temperature in the combustion chamber 101 reaches the set temperature, the hot air in the combustion chamber 101 passes through the air inlet pipe and is blown upward from the bottom of the drying chamber 102, blowing the lithium slag in the drying chamber 102 upward into a suspended state, and the air in the drying chamber 102 is discharged from the air outlet pipe 103.

[0046] Through the design structure of the hot air furnace 100, hot air can be blown into the drying chamber 102 evenly. By setting the limiting mesh layer 104, the lithium slag is effectively prevented from entering the air inlet pipe 200 and the air outlet pipe 103, thereby ensuring the smooth progress of the drying process. The hot air blows the lithium slag into a suspended state, increasing the contact area between the lithium slag and the hot air, improving the drying efficiency, and ensuring that the lithium slag can be dried quickly and evenly, thereby providing high-quality lithium slag raw materials for the subsequent preparation of high-performance curing agents, which helps to improve the performance of the curing agent and the curing effect of soft soil.

[0047] In this embodiment, in the preparation step 1), the bottom of the drying chamber 102 has an air inlet 201, the air inlet 201 is covered with a restricting mesh layer 104, and the air inlet 201 is connected to the air inlet pipe 200; a track ring 202 is provided in the drying chamber 102, and the track ring 202 surrounds the outer periphery of the air inlet 201;

[0048] The orbital ring 202 is provided with a rotating ring 203, and the rotating ring 203 is provided with a plurality of inclined blades 204. The plurality of blades 204 are arranged around the circumference of the rotating ring 203 at intervals. The lower ends of the blades 204 are docked on the rotating ring 203, and the upper ends of the blades 204 are arranged inclined toward the upper side of the air inlet 201. The inclination angles of the plurality of blades 204 are different.

[0049] In preparation step 1), when the air inlet pipe 200 blows hot air into the bottom of the drying chamber 102 through the air inlet 201, the hot air drives the multiple blades 204 to rotate the rotating ring 203 relative to the track ring 202, and the multiple blades 204 rotate synchronously with the rotating ring 203 to make the hot air form a vortex shape.

[0050] Through the vortex-shaped hot air flow mode, it can more fully contact with the lithium slag, further improving the drying efficiency and uniformity. At the same time, the different inclination angles of the blades 204 make the flow of hot air in the drying chamber 102 more complex and uniform, enhancing the drying effect, providing a strong guarantee for the preparation of high-quality curing agent, thereby indirectly improving the curing effect of soft soil.

[0051] In this embodiment, in the preparation step 1), the dried lithium slag is ball-milled using a ball mill to form a powdered lithium slag powder having a specific surface area of ​​600 to 700 m2 / g. In this way, the lithium slag particle size is reduced and the specific surface area is increased. The powdered lithium slag powder can better mix and react with other components in the curing agent, give full play to its activity, and improve the gelling properties and strength of the curing agent.

[0052] The curing agent prepared based on lithium slag provided in this embodiment is not limited to soft soil curing, but can also be used for floor treatment, concrete base surface treatment and soil curing according to actual construction conditions.

[0053] The preparation method of the curing agent based on lithium slag provided in this embodiment also provides specific experimental steps for making test blocks to obtain test data, as follows:

[0054] 1) First, the lithium slag is preliminarily screened, and then dried at 105°C for 10 hours in a hot air furnace to reduce the moisture content to below 2%. The lithium slag is then ball milled for 2 hours to apply mechanical energy to increase the surface energy, increase the specific surface area and internal defects of the lithium slag powder, and finally sieved appropriately with a 325-mesh fine sieve to remove large particles for standby use;

[0055] 2) Stir the curing agent material into a uniform state according to the proportion;

[0056] 3) Place the waste soil samples dug out during construction in a drying oven at 105°C and dry them immediately. Grind and sieve the dried soil to a mesh size of ≤2mm.

[0057] 4) Mix the sieved waste soft soil with the curing agent and additives in the ratio of (60-90): (10-30): (0.05-0.3), add water according to the designed parameters and mix evenly, and stir the mixed mixture again;

[0058] 5) After the mixing process is completed, the material is filled into the test mold and the solidification time is further measured.

[0059] 6) Place the stirred slurry into the mold and vibrate it, seal it with plastic film and place it in a standard curing box for curing. After 24 hours, demould it and cure it to the specified age, and then measure the compressive strength.

[0060] Test blocks were made according to the above ratio and production process, and the test data obtained are as follows:

[0061]

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a curing agent based on lithium slag, characterized in that: The method comprises the following preparation steps: 1) preparing a curing material, an additive and an alkali activator, wherein the curing material includes silicate cement, sulfoaluminate cement, mineral powder, gypsum, fly ash, stone powder and lithium slag, the additive contains quicklime, and the alkali activator includes calcium carbonate and sodium hydroxide. The ratio of the curing material, the additive and the alkali activator is (60-80): (10-30): (5-10) by weight; 2) The curing material, additives and alkali activator are placed in a mixer, and the mixer mixes the curing material, additives and alkali activator to form a curing agent for mixing with soft soil to solidify the soft soil.

2. The method for preparing a curing agent based on lithium slag according to claim 1, wherein: In the preparation step 1), the silicate cement is of P·O42.5 grade, the mineral powder is of S95 or S105 grade, the gypsum includes desulfurized gypsum, anhydrite or hemihydrate gypsum, and the lithium slag is waste generated in the lithium salt extraction process.

3. The method for preparing a curing agent based on lithium slag according to claim 1, wherein: In the preparation step 1), based on the mass proportion, the silicate cement accounts for 10% to 40%, the sulfoaluminate cement accounts for 1% to 15%, the mineral powder accounts for 20% to 60%, the gypsum accounts for 10% to 30%, the fly ash accounts for 1% to 30%, the stone powder accounts for 1% to 10%, and the lithium slag accounts for 10% to 30%.

4. The method for preparing a curing agent based on lithium slag according to claim 1, wherein: In the preparation step 1), the additive is white quicklime powder, and the purity of the additive is higher than 90%.

5. The method for preparing a curing agent based on lithium slag according to claim 1, wherein: In the preparation step 1), the lithium slag is crushed by a crusher and then screened by a screening device.

6. The method for preparing a curing agent based on lithium slag according to any one of claims 1 to 5, characterized in that: In the preparation step 1), the screened lithium slag is dried with hot air in a hot air furnace to reduce the moisture content of the lithium slag to less than 2%.

7. The method for preparing a curing agent based on lithium slag according to claim 6, wherein: In the preparation step 1), the hot blast furnace includes a combustion chamber and a drying chamber, the bottom of the drying chamber is connected to the combustion chamber through an air inlet pipe, the top of the drying chamber is provided with an air outlet pipe, the air inlet pipe and the air outlet pipe are respectively provided with a restriction mesh layer, the restriction mesh layer has a mesh, and the diameter of the mesh is smaller than the particle size of the lithium slag; When the temperature in the combustion chamber reaches the set temperature, the hot air in the combustion chamber passes through the air inlet pipe and is blown upward from the bottom of the drying chamber, blowing the lithium slag in the drying chamber upward into a suspended state, and the air in the drying chamber is discharged from the air outlet pipe.

8. The method for preparing a curing agent based on lithium slag according to claim 7, wherein: In the preparation step 1), the bottom of the drying chamber has an air inlet, the air inlet is covered with a restrictive mesh layer, and the air inlet is connected to the air inlet pipe; the drying chamber is provided with a track ring, and the track ring surrounds the outer circumference of the air inlet; The orbital ring is provided with a rotating ring, and the rotating ring is provided with a plurality of blades arranged obliquely, and the plurality of blades are arranged around the circumference of the rotating ring at intervals; the lower ends of the blades are docked on the rotating ring, and the upper ends of the blades are arranged obliquely toward the upper side of the air inlet, and the inclination angles of the plurality of blades are different; In the preparation step 1), when the air inlet pipe blows hot air into the drying chamber from the bottom through the air inlet, the hot air drives the multiple blades to rotate the rotating ring relative to the track ring, and the multiple blades rotate synchronously with the rotating ring to make the hot air form a vortex.

9. The method for preparing a curing agent based on lithium slag according to any one of claims 1 to 5, wherein: In the preparation step 1), the dried lithium slag is ball-milled by a ball mill to form a powdered lithium slag powder with a specific surface area of ​​600 to 700 m 2 / g.

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