Curing agent test part preparation method based on lithium slag formation

Abstract

The invention relates to the technical field of lithium slag, and discloses a preparation method of a curing agent test part formed based on lithium slag, which comprises the following preparation steps: 1) screening the lithium slag, and grinding the screened lithium slag to make the lithium slag be powdery; 2) preparing a curing material, an additive and an alkali activator; 3) putting the curing material, the additive and the alkali activator into a stirrer, and stirring and mixing the curing material, the additive and the alkali activator by the stirrer to form a curing agent; (4) the waste soft soil is dried, and the dried waste soft soil is screened; 5) stirring and mixing the curing agent, the waste soft soil and the water body to form slurry; (6) putting the slurry into a mold, carrying out compaction treatment, covering the mold with a film, carrying out sealed maintenance, and solidifying the slurry in the mold to form a test piece; through a series of optimized preparation steps, the utilization rate of the lithium slag in a curing agent test workpiece is remarkably improved.

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 test piece based on lithium slag. Background Art

[0002] Lithium slag is an industrial by-product produced during the extraction of lithium ore, mainly from the extraction process of lepidolite and spodumene. The fine porous structure of lithium slag makes it easy for dust to spread when stored in the open air. In addition, the acidic and alkaline leachate released from the lithium slag pile poses a health threat to the surrounding living environment and surrounding ecosystems.

[0003] At present, the resource utilization channels of lithium slag are quite narrow, and the actual recycling and reuse scale is limited. The industry urgently needs to explore new utilization paths to improve its comprehensive utilization efficiency. The preparation of high-performance curing agent materials through lithium slag provides an effective way for the resource utilization of lithium slag.

[0004] In the existing technology, the utilization rate of lithium slag in curing agent test parts is low, mainly due to the following problems:

[0005] Because lithium slag particles are small and unevenly distributed, and lack effective screening and grinding steps, they are difficult to fully mix in the curing agent, resulting in insufficient dispersibility and reactivity. At the same time, lithium slag contains various impurities that interfere with the performance of the curing agent, especially when combined with waste soft soil, resulting in poor curing effect.

[0006] In addition, the ratio between the curing material, additives and alkaline activators is not optimized enough, resulting in unstable curing agent performance. The choice of additives is also relatively simple, usually only using common materials such as quicklime, which makes it difficult to solve the moisture adsorption and chemical stability problems caused by lithium slag.

[0007] Furthermore, waste soft soil usually contains a lot of impurities and moisture. The existing technology only performs simple screening, which will cause problems such as insufficient strength and poor durability when combined with a curing agent.

[0008] In addition, the uneven mixing process of the curing agent, waste soft soil and water and the unstable curing conditions are factors that cannot be ignored. Summary of the Invention

[0009] The object of the present invention is to provide a method for preparing a curing agent test piece based on lithium slag, aiming to solve the problem of low utilization rate of lithium slag in curing agent test pieces in the prior art.

[0010] The present invention is achieved by a method for preparing a test piece of a curing agent based on lithium slag, comprising the following preparation steps:

[0011] 1) Screening the lithium slag, and then grinding the screened lithium slag to make the lithium slag into powder;

[0012] 2) preparing 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 contain quicklime, and the alkali activators include calcium carbonate and sodium hydroxide. The ratio of the curing materials, additives and alkali activators is (60-80): (10-30): (5-10) by weight;

[0013] 3) placing the curing material, additives and alkali activator in a blender, and stirring and mixing the curing material, additives and alkali activator in the blender to form a curing agent;

[0014] 4) Drying the waste soft soil excavated from the construction site and screening the dried waste soft soil;

[0015] 5) Stirring and mixing the curing agent, waste soft soil and water to form a slurry;

[0016] 6) The slurry is placed in a mold. After the slurry is vibrated in the mold, a film is covered on the mold for sealing and curing. The slurry solidifies in the mold to form a test specimen.

[0017] Furthermore, in the preparation step 1), the lithium slag is screened and then dried in a hot air furnace to reduce the moisture content of the lithium slag to below 2%.

[0018] Furthermore, in the preparation step 1), the dried lithium slag is ground using a ball mill to make the lithium slag into powder.

[0019] Furthermore, in the preparation step 4), the waste soft soil is placed in a drying box for drying, and then the dried waste soft soil is ground and sieved.

[0020] Furthermore, in the preparation step 5), the ratio of the waste soft soil to the curing agent is (60-90): (10-30) by mass.

[0021] Furthermore, in the preparation step 2), 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.

[0022] Furthermore, in the preparation step 2), 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%.

[0023] Furthermore, in the preparation step 2), the additive is white quicklime powder, and the purity of the additive is higher than 90%.

[0024] Furthermore, in the preparation step 6), after the slurry is placed in the mold, the mold is fixed on a vibration table that vibrates longitudinally; the vibration table has a groove for placing the mold, and a pressing plate is provided above the groove, the pressing plate is connected to the vibration table, and a plurality of springs are connected to the pressing plate;

[0025] In the preparation step 6), after the mold is placed in the groove, the multiple springs of the pressure plate press downward on the mold, and the multiple springs are in a compressed state. After the pressure plate and the vibration table clamp the mold facing each other, the vibration table drives the pressure plate to vibrate synchronously longitudinally, and the multiple springs elastically deform and press against the mold, so that the mold is in a variable frequency vibration state.

[0026] Furthermore, in the preparation step 6), the vibration table is provided with a plurality of through holes extending vertically therethrough, and a longitudinally movable impact shaft is passed through the through holes; during the longitudinal vibration of the vibration table, the impact shafts in the plurality of through holes alternately impact the mold from bottom to top to increase the deformation of the spring, so that the vibration table is in a variable frequency vibration state.

[0027] Compared with the prior art, the method for preparing a curing agent test piece based on lithium slag provided by the present invention significantly improves the utilization rate of lithium slag in the curing agent test piece through optimized preparation steps and solves many shortcomings of the prior art. The specific technical effects are as follows:

[0028] 1) By screening and grinding, the lithium slag is converted into a uniform powder, effectively solving the problem of fine and uneven distribution of lithium slag particles. This efficient pretreatment method not only improves the dispersibility and reactivity of lithium slag in the curing agent, but also provides a basis for the subsequent mixing and curing process, thereby significantly improving the utilization rate of lithium slag;

[0029] 2) By precisely controlling the ratio of curing materials, additives and alkaline activators, the performance stability and high efficiency of the curing agent are ensured. In particular, the addition of quicklime as an additive, and calcium carbonate and sodium hydroxide as alkaline activators can effectively improve the chemical stability and strength performance of the curing agent;

[0030] 3) Through drying and screening, impurities and excess water in the waste soft soil are removed, which significantly improves its bonding effect with the curing agent and further enhances the overall performance of the product;

[0031] 4) Through the steps of mixing, compaction, and sealing and curing, the uniformity of the slurry and the molding quality of the parts are ensured. In particular, the sealing and curing measures effectively control the curing environment and prevent moisture loss, thereby improving the strength and durability of the final test specimens. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 1. It is a schematic flow chart of a method for preparing a curing agent test piece based on lithium slag provided by the present invention;

[0033] Figure 2 It is a structural schematic diagram of the vibration table and mold provided by the present invention;

[0034] In the figure: vibration table 100, groove 101, pressure plate 102, spring 103, through hole 104, impact shaft 105, mold 106. DETAILED DESCRIPTION

[0035] 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.

[0036] The implementation of the present invention is described in detail below with reference to specific embodiments.

[0037] 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.

[0038] Reference Figure 1-2 The figure shows a preferred embodiment of the present invention.

[0039] The method for preparing a test piece of a curing agent formed based on lithium slag includes the following preparation steps:

[0040] 1) Screening the lithium slag, and then grinding the screened lithium slag to make the lithium slag into powder;

[0041] 2) Prepare curing materials, additives and alkali activators, the curing materials include silicate cement, sulfoaluminate cement, mineral powder, gypsum, fly ash, stone powder and lithium slag, the additives contain 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;

[0042] 3) placing the curing material, additives and alkali activator in a blender, and stirring and mixing the curing material, additives and alkali activator in the blender to form a curing agent;

[0043] 4) Drying the waste soft soil excavated from the construction site and screening the dried waste soft soil;

[0044] 5) Stirring and mixing the curing agent, waste soft soil and water to form a slurry;

[0045] 6) Place the slurry in a mold, vibrate the slurry in the mold, cover the mold with a film for sealing and curing, and solidify the slurry in the mold to form a test specimen.

[0046] The above-mentioned method for preparing a curing agent test piece based on lithium slag formation significantly improves the utilization rate of lithium slag in the curing agent test piece through optimized preparation steps and solves many shortcomings in the existing technology. The specific technical effects are as follows:

[0047] 1) By screening and grinding, the lithium slag is converted into a uniform powder, effectively solving the problem of fine and uneven distribution of lithium slag particles. This efficient pretreatment method not only improves the dispersibility and reactivity of lithium slag in the curing agent, but also provides a basis for the subsequent mixing and curing process, thereby significantly improving the utilization rate of lithium slag;

[0048] 2) By precisely controlling the ratio of curing materials, additives and alkaline activators, the performance stability and high efficiency of the curing agent are ensured. In particular, the addition of quicklime as an additive, and calcium carbonate and sodium hydroxide as alkaline activators can effectively improve the chemical stability and strength performance of the curing agent;

[0049] 3) Through drying and screening, impurities and excess water in the waste soft soil are removed, which significantly improves its bonding effect with the curing agent and further enhances the overall performance of the product;

[0050] 4) Through the steps of mixing, compaction, and sealing and curing, the uniformity of the slurry and the molding quality of the parts are ensured. In particular, the sealing and curing measures effectively control the curing environment and prevent moisture loss, thereby improving the strength and durability of the final test specimens.

[0051] In this embodiment, in the preparation step 1), after the lithium slag is screened, it is dried in a hot air furnace to reduce the moisture content of the lithium slag to below 2%. This treatment effectively reduces the moisture content in the lithium slag, avoids the adverse effects of high moisture content on the subsequent mixing and curing process, thereby improving the dispersibility and reactivity of the lithium slag in the curing agent, and laying the foundation for improving its utilization rate.

[0052] In this embodiment, in the preparation step 1), the lithium slag after drying is ground using a ball mill to make the lithium slag into a powder; in this way, the particle size of the lithium slag is more uniform and fine, which enhances its mixing effect with other materials, further improves the reactivity of the lithium slag in the curing agent, solves the problem of uneven distribution of lithium slag particles and difficulty in sufficient mixing, and effectively improves the utilization rate of the lithium slag in the curing agent test piece.

[0053] In this embodiment, in preparation step 4), the waste soft soil is placed in a drying oven for drying, and then the dried waste soft soil is ground and sieved; this treatment process not only removes excess moisture from the waste soft soil, but also improves its particle uniformity through grinding and sieving, enabling it to better combine with the curing agent, thereby improving the mixing effect of the waste soft soil and the curing agent, providing a guarantee for the preparation of test parts with better performance.

[0054] In this embodiment, in the preparation step 5), the ratio of the waste soft soil to the curing agent is (60-90): (10-30) by mass. By optimizing the ratio of the waste soft soil to the curing agent, the two can better interact with each other and give full play to their respective advantages, thereby improving the overall performance of the test piece and further improving the utilization rate of the lithium slag in the curing agent test piece.

[0055] In this embodiment, in the preparation step 2), 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.

[0056] By selecting specific grades of Portland cement and mineral powder, as well as a variety of gypsum types, the performance stability and high efficiency of the curing agent are ensured. At the same time, the use of lithium slag as a waste material realizes the recycling of resources and improves the utilization rate of lithium slag.

[0057] In this embodiment, in the preparation step 2), 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%.

[0058] By precisely controlling the proportion of each component, the formula of the curing agent is optimized so that it can better adapt to the needs of different application scenarios. At the same time, the proportion of lithium slag in the curing agent is increased, further improving its utilization rate, thereby achieving high utilization rate of lithium slag.

[0059] In this embodiment, in the preparation step 2), the additive is white quicklime powder, and the purity of the additive is higher than 90%. The use of high-purity quicklime powder as an additive can effectively improve the chemical stability and strength properties of the curing agent, optimize the performance of the curing agent, and provide strong support for increasing the utilization rate of lithium slag in curing agent test pieces.

[0060] In this embodiment, in preparation step 6), after the slurry is placed in the mold 106, the mold 106 is fixed on a vibration table 100 that vibrates longitudinally; the vibration table 100 has a groove 101 for placing the mold 106, and a pressure plate 102 is provided above the groove 101. The pressure plate 102 is connected to the vibration table 100, and a plurality of springs 103 are connected to the pressure plate 102;

[0061] In preparation step 6), after the mold 106 is placed in the groove 101, the multiple springs 103 of the pressure plate 102 press downward on the mold 106, and the multiple springs 103 are in a compressed state. After the pressure plate 102 and the vibration table 100 clamp the mold 106 facing each other, the vibration table 100 drives the pressure plate 102 to vibrate synchronously longitudinally, and the multiple springs 103 elastically deform and press against the mold 106, so that the mold 106 is in a variable frequency vibration state.

[0062] In this way, the density of the slurry can be effectively improved, the quality and performance of the test pieces can be ensured, and the utilization rate of lithium slag in the curing agent test pieces can be further improved.

[0063] In this embodiment, in preparation step 6), a plurality of through holes 104 extending vertically therethrough are provided in the vibration table 100, and a longitudinally movable impact shaft 105 is passed through the through hole 104; during the longitudinal vibration of the vibration table 100, the impact shafts 105 in the plurality of through holes 104 alternately impact the mold 106 from bottom to top to increase the deformation of the spring 103, so that the vibration table 100 is in a variable frequency vibration state.

[0064] By using the alternating impact method, the vibration effect is further enhanced, the density and uniformity of the slurry are improved, thereby improving the overall performance of the test piece and further improving the utilization rate of lithium slag in the curing agent test piece.

[0065] In this embodiment, the slurry obtained according to the preparation steps meets the relevant provisions of CJ / T 526-2018 "Soft Soil Solidifier": the apparent density of the finished product shall not be less than 2.8g / cm 3, fineness (80μm square hole sieve residue) is not higher than 10%, initial net slurry fluidity is not less than 100mm, and initial setting time is not less than 45min.

[0066] In this embodiment, during the hydration process of the solidifying material, silicate cement and sulphoaluminate cement will generate hydrated calcium silicate and hydrated calcium sulphoaluminate respectively. Secondly, quicklime is extremely unstable and easily deliquesces when it comes into contact with water to generate a new product, slaked lime. The mixture is alkaline as a whole, which stimulates the activity of mineral powder, fly ash and lithium slag, thereby enhancing the long-term strength performance of the material.

[0067] The sulphoaluminate cement provided in this embodiment must be higher than 425 grade, and the fly ash must meet the Class II F standard or above.

[0068] The method for preparing a test piece of a curing agent based on lithium slag provided in this embodiment also provides specific experimental steps for making a test block to obtain test data, as follows:

[0069] 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;

[0070] 2) Stir the curing agent material into a uniform state according to the proportion;

[0071] 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.

[0072] 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;

[0073] 5) After the mixing process is completed, the material is filled into the test mold and the solidification time is further measured.

[0074] 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.

[0075] Test blocks were made according to the above ratio and production process, and the test data obtained are as follows:

[0076]

[0077] 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 test piece based on lithium slag formation, characterized in that: The method comprises the following preparation steps: 1) Screening the lithium slag, and then grinding the screened lithium slag to make the lithium slag into powder; 2) preparing 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 contain quicklime, and the alkali activators include calcium carbonate and sodium hydroxide. The ratio of the curing materials, additives and alkali activators is (60-80): (10-30): (5-10) by weight; 3) placing the curing material, additives and alkali activator in a blender, and stirring and mixing the curing material, additives and alkali activator in the blender to form a curing agent; 4) Drying the waste soft soil excavated from the construction site and screening the dried waste soft soil; 5) Stirring and mixing the curing agent, waste soft soil and water to form a slurry; 6) The slurry is placed in a mold. After the slurry is vibrated in the mold, a film is covered on the mold for sealing and curing. The slurry solidifies in the mold to form a test specimen.

2. The method for preparing a curing agent test piece based on lithium slag formation according to claim 1, characterized in that: In the preparation step 1), the lithium slag is screened and then dried in a hot air furnace to reduce the moisture content of the lithium slag to below 2%.

3. The method for preparing a curing agent test piece based on lithium slag formation according to claim 1, characterized in that: In the preparation step 1), the dried lithium slag is ground using a ball mill to make the lithium slag into powder.

4. The method for preparing a curing agent test piece based on lithium slag formation according to claim 1, characterized in that: In the preparation step 4), the waste soft soil is placed in a drying box for drying, and then the dried waste soft soil is ground and sieved.

5. The method for preparing a curing agent test piece based on lithium slag formation according to claim 1, characterized in that: In the preparation step 5), the ratio of the waste soft soil to the curing agent is (60-90): (10-30) by mass.

6. The method for preparing a curing agent test piece based on lithium slag formation according to claim 1, characterized in that: In the preparation step 2), 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.

7. The method for preparing a curing agent test piece based on lithium slag formation according to claim 1, characterized in that: In the preparation step 2), the silicate cement accounts for 10% to 40% by mass, the sulfoaluminate cement accounts for 1% to 15% by mass, the mineral powder accounts for 20% to 60% by mass, the gypsum accounts for 10% to 30% by mass, the fly ash accounts for 1% to 30% by mass, the stone powder accounts for 1% to 10% by mass, and the lithium slag accounts for 10% to 30% by mass.

8. The method for preparing a curing agent test piece based on lithium slag formation according to claim 1, characterized in that: In the preparation step 2), the additive is white quicklime powder, and the purity of the additive is higher than 90%.

9. The method for preparing a curing agent test piece based on lithium slag formation according to any one of claims 1 to 8, characterized in that: In the preparation step 6), after the slurry is placed in the mold, the mold is fixed on a vibration table that vibrates longitudinally; the vibration table has a groove for placing the mold, and a pressing plate is provided above the groove, the pressing plate is connected to the vibration table, and a plurality of springs are connected to the pressing plate; In the preparation step 6), after the mold is placed in the groove, the multiple springs of the pressure plate press downward on the mold, and the multiple springs are in a compressed state. After the pressure plate and the vibration table clamp the mold facing each other, the vibration table drives the pressure plate to vibrate synchronously longitudinally, and the multiple springs elastically deform and press against the mold, so that the mold is in a variable frequency vibration state.

10. The method for preparing a curing agent test piece based on lithium slag formation according to claim 9, characterized in that: In the preparation step 6), the vibration table is provided with a plurality of through holes extending vertically therethrough, and a longitudinally movable impact shaft is passed through the through holes; during the longitudinal vibration of the vibration table, the impact shafts in the plurality of through holes alternately impact the mold from bottom to top to increase the deformation of the spring, so that the vibration table is in a variable frequency vibration state.

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