Tailing-based low-temperature response type sewage adsorption material and preparation method thereof
By preparing tailings-based low-temperature responsive wastewater adsorption materials, the problems of tailings accumulation and high activated carbon costs were solved, stable wastewater treatment and resource utilization were achieved, production costs were reduced, and environmental safety and resource utilization efficiency were improved.
Patent Information
- Application Number
- CN202510594022.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-09
- Publication Date
- 2025-09-16
AI Technical Summary
The accumulation of mine tailings occupies land resources, poses a risk of dam collapse, and pollutes the environment with heavy metals. Traditional tailings treatment technology is complex and results in serious waste of resources. Activated carbon production relies on high-cost raw materials, which puts great pressure on the environment.
Low-temperature responsive sewage adsorption materials were prepared using sand and gravel mine tailings, upper weathered materials and binders. SiO2 and Al2O3 formed an [AlO4/SiO4] tetrahedral network, and Fe2O3 and montmorillonite produced Fe-O-Si bonding to form a stable structure and active sites. The proportion of weathered materials was adjusted according to different sewage concentrations, and hydrochloric acid or alkali modification treatment and gradient ball milling process were used to prepare mesoporous and microporous structures.
It achieves low-cost and stable sewage adsorption performance, adapts to different pollution loads, reduces production costs, reduces solid waste storage, improves resource utilization, and meets the requirements of green development.
Smart Images
Figure BDA0005393994540000061 
Figure BDA0005393994540000071
Abstract
Description
Technical Field
[0001] The present invention relates to a tailings-based low-temperature responsive sewage adsorption material and a preparation method thereof, which is applicable to solid waste resource utilization and sewage treatment material technology. Background Art
[0002] As the scale of mineral resource development expands, the amount of mine tailings accumulated continues to climb. Traditional storage methods not only occupy a large amount of land resources but also pose the risk of dam failure. Heavy metals and harmful components remaining in the tailings can easily pollute the water and soil environment through leaching and dust generation, threatening ecological safety. Current mainstream tailings treatment technologies, such as landfill and wet discharge, are complex and wasteful, making them difficult to meet the needs of green mine construction.
[0003] At the same time, activated carbon is an important adsorption material in the field of pollution control. Its traditional production process relies on high-quality coal or wood raw materials. The cost of obtaining raw materials is high and is accompanied by the consumption of forest resources, which aggravates the environmental burden and economic pressure. There is an urgent need to explore low-cost activated carbon preparation technology. Summary of the Invention
[0004] The technical problem to be solved by the present invention is: in response to the above-mentioned problems, a tailings-based low-temperature responsive sewage adsorption material and a preparation method thereof are provided.
[0005] The technical solution adopted by the present invention is: a tailings-based low-temperature responsive sewage adsorption material, comprising:
[0006] Sand and gravel mine tailings, containing SiO2 and Fe2O3;
[0007] The upper layer of weathered material contains kaolin and montmorillonite;
[0008] Binders, used to bind the tailings and weathered material together;
[0009] The SiO2 in the tailings can interact with the Al2O3 in the weathered material to form an [AlO4 / SiO4] tetrahedral network structure; the Fe2O3 in the tailings can produce Fe-O-Si bonding with the montmorillonite in the weathered material.
[0010] The weight ratio of each component is:
[0011] Sand and gravel mine tailings 40-65wt%;
[0012] Upper layer weathered material 25-50wt%;
[0013] Binder 5-10wt%.
[0014] The proportion of upper weathered materials is adjusted according to the concentration of macromolecular pollutants in the treated wastewater. The higher the concentration of macromolecular pollutants, the higher the proportion of upper weathered materials.
[0015] When COD in the treated sewage is ≤300mg / L, the proportion of weathered materials is 25-35%;
[0016] When the COD in the treated wastewater is 300-500 mg / L, the proportion of weathered materials is 35-45%;
[0017] When the COD in the treated sewage is ≥500 mg / L, the proportion of weathered materials is 45-50%.
[0018] The binder is a sodium silicate solution.
[0019] A method for preparing the tailings-based low-temperature responsive sewage adsorption material comprises:
[0020] Carry out hydrochloric acid activation treatment on sand and gravel mine tailings;
[0021] The activated tailings are mixed with the weathered materials in a gradient process, and the mixing process is combined with ball milling;
[0022] The mixed material was subjected to primary activation and maintained at a temperature of 95°C for 2.5 hours;
[0023] After the primary activation, the secondary activation was carried out at a temperature of 115°C for 1.2 hours.
[0024] The hydrochloric acid activation treatment of the sand and gravel mine tailings comprises:
[0025] Soak in 4-6% hydrochloric acid solution for 45-60 minutes, with a solid-liquid ratio of 1:3-1:5.
[0026] A method for preparing the tailings-based low-temperature responsive sewage adsorption material comprises:
[0027] Alkali modification treatment of sand and gravel mine tailings;
[0028] The modified tailings are directly mixed with the weathered material;
[0029] The mixed material was subjected to a single-stage activation at a temperature of 105°C for 3 hours.
[0030] The alkali modification treatment of the sand and gravel mine tailings comprises:
[0031] Ultrasonic treatment was performed using 0.5-1 mol / L NaOH solution for 20-30 minutes.
[0032] An application of the tailings-based low-temperature responsive sewage adsorption material in sewage treatment.
[0033] The present invention utilizes sand and gravel mine tailings, upper layer weathered material, and a binder to prepare a wastewater adsorption material. The tailings and weathered material are mixed to form an [AlO4 / SiO4] tetrahedral network, significantly enhancing its structural stability and ensuring good adsorption performance even at low temperatures. The mixture of tailings and weathered material generates Fe-O-Si bonding, creating more active sites on the material surface. By preparing wastewater adsorption material from sand and gravel mine tailings, the present invention achieves a low-cost solution while simultaneously achieving the dual goals of tailings resource utilization and the production of environmentally friendly materials. DETAILED DESCRIPTION
[0034] Example 1: This example is a tailings-based low-temperature responsive sewage adsorption material, comprising: sand and gravel mine tailings, upper weathered material and a binder, wherein the sand and gravel mine tailings have a particle size of 0.5-2 mm, containing SiO2 ≥ 58%, Al2O3 12-18%, and Fe2O3 5-9%; the upper weathered material contains kaolin ≥ 35%, montmorillonite 8-15%, and organic matter 3-8%; the binder is a sodium silicate solution (modulus 2.2-2.8).
[0035] The weight ratio of each component of the sewage adsorption material in this example is:
[0036] Sand and gravel mine tailings 40-65wt%;
[0037] Upper layer weathered material 25-50wt%;
[0038] Binder 5-10wt%.
[0039] In terms of raw material matching, this embodiment cleverly utilizes the characteristics of tailings and weathered materials to enhance the performance of the adsorption material through the synergistic effect of the two.
[0040] Tailings are rich in SiO2, while weathered materials contain a certain amount of Al2O3. During the material preparation process, SiO2 and Al2O3 interact to form an [AlO4 / SiO4] tetrahedral network. This unique structure acts like a sturdy framework, effectively resisting damage to the material structure caused by low-temperature environments.
[0041] Under low-temperature conditions, the structure of ordinary materials is easily changed, resulting in a decrease in adsorption performance. However, due to the presence of the [AlO4 / SiO4] tetrahedral network, the sewage adsorbent material of this embodiment has significantly improved structural stability, thereby ensuring that it can still maintain good adsorption performance in low-temperature environments.
[0042] The Fe₂O₃ in the tailings and the montmorillonite in the weathered material form Fe-O-Si bonds. This bonding creates more active sites on the material's surface. These active sites act like "adsorption hooks" on the material's surface, better binding to pollutant molecules in wastewater. The increased density of surface active sites means the material can adsorb more pollutants, thereby improving adsorption efficiency. In actual wastewater treatment, more active sites enable the material to more quickly capture and remove harmful substances from wastewater, enhancing treatment effectiveness.
[0043] In this embodiment, the proportion of the upper layer of weathered materials is adjusted according to the concentration of macromolecular pollutants in the treated sewage. The higher the concentration of macromolecular pollutants, the higher the proportion of the upper layer of weathered materials.
[0044] Research has found that for every 10% increase in the amount of weathered material added, the surface hydroxyl density of the wastewater adsorption material increases by 0.3 mmol / g. Surface hydroxyl groups play a crucial role in the adsorption process, chemically reacting with pollutants in wastewater, thereby anchoring them to the material's surface. By adjusting the amount of weathered material added, the surface hydroxyl density can be flexibly controlled, thereby influencing the material's adsorption properties. When pollutant concentrations in wastewater are high, appropriately increasing the amount of weathered material added and raising the surface hydroxyl density can enhance the material's adsorption capacity.
[0045] When the COD concentration increases, the content of macromolecular pollutants in the sewage will also increase accordingly. In this embodiment, the proportion of mesopores is increased by increasing the proportion of weathered materials, and the proportion of mesopores is increased from 45% to 55%. Mesopores have a larger pore size and can accommodate macromolecular pollutants. In this way, the material can better adapt to sewage with different pollution loads and effectively remove pollutants therein. For example, when treating sewage with high COD concentrations such as industrial wastewater, increasing the proportion of weathered materials to expand the proportion of mesopores can significantly improve the material's adsorption efficiency for macromolecular organic matter.
[0046] In this embodiment, when the COD in the treated sewage is ≤300 mg / L, the weathered material accounts for 25-35%; when the COD in the treated sewage is 300-500 mg / L, the weathered material accounts for 35-45%; when the COD in the treated sewage is ≥500 mg / L, the weathered material accounts for 45-50%.
[0047] The function of the binder in this embodiment is to firmly combine the tailings and the weathered material together to ensure the molding and overall performance of the material.
[0048] Example 2: This example describes a tailings-based, low-temperature-responsive wastewater adsorption material. The material comprises 60% tailings (65% SiO), 35% weathered material (40% kaolin), and 5% binder. The high SiO2 content in the tailings provides a sufficient silicon source for forming the [AlO4 / SiO4] tetrahedral network, while the high kaolin content in the weathered material contributes to improved adsorption performance and structural stability. The binder securely bonds the tailings and weathered material, ensuring the material's formability and overall performance.
[0049] The method for preparing the tailings-based low-temperature responsive sewage adsorption material in this embodiment includes:
[0050] ①. Activate the sand and gravel mine tailings with hydrochloric acid by soaking them in a 4-6% hydrochloric acid solution for 45-60 minutes, with a solid-to-liquid ratio of 1:3-1:5. Hydrochloric acid activation removes impurities and oxides from the tailings surface and increases the active sites on the tailings surface.
[0051] ② The activated tailings are mixed with the weathered material in a gradient process, with ball milling used during the mixing process. The activated tailings and weathered material are mixed in a gradient process, with the weathered material ratio gradually decreasing from 65% to 50% and finally to 40%. This gradient mixing method ensures full contact and mixing between the tailings and weathered material, ensuring uniform material properties. Ball milling plays a key role in the mixing process, further refining the particles, increasing the material's specific surface area, and improving adsorption performance.
[0052] ③ The mixed material undergoes a primary activation process, maintaining it at 95°C for 2.5 hours. During this process, a mesoporous structure with pore sizes of 20-50 nm begins to form within the material. The mesopores form because, at a specific temperature, the minerals within the material undergo a lattice restructuring reaction, creating channels suitable for the entry of large molecular contaminants.
[0053] ④ After the primary activation, secondary activation is performed, maintaining the temperature at 115°C for 1.2 hours. The primary function of secondary activation is to generate micropores ranging from 0.8 to 2 nm. The presence of micropores increases the material's adsorption capacity for small molecule pollutants, further improving the material's adsorption performance. The formation of micropores is the result of further restructuring and adjustment of the mineral lattice. By precisely controlling the activation temperature and time, the number and size of micropores can be ensured to meet design requirements.
[0054] The adsorption material prepared by the above process has a specific surface area of 198m 2 / g. A larger specific surface area means the material has more surface contact with wastewater, providing more adsorption sites. At -25°C, the ammonia nitrogen adsorption capacity reached 82 mg / g. This demonstrates that the material maintains excellent ammonia nitrogen adsorption performance even at low temperatures, effectively removing ammonia nitrogen pollutants from wastewater.
[0055] Example 3: This example describes a tailings-based, low-temperature-responsive wastewater adsorption material composed of 45% tailings, 50% weathered material, and 5% binder. The increased proportion of weathered material is intended to better handle high-pollution wastewater. The rich mineral components in the weathered material, such as kaolin and montmorillonite, provide more active sites and adsorption space, enhancing the material's adsorption capacity for pollutants.
[0056] The method for preparing the tailings-based low-temperature responsive sewage adsorption material in this embodiment includes:
[0057] Ⅰ. Alkali modification treatment of tailings: ultrasonic treatment with 0.5-1 mol / L NaOH solution for 20-30 minutes. Alkali modification can change the chemical properties of the tailings surface, increase the surface negative charge, and enhance the electrostatic adsorption between the tailings and pollutants.
[0058] Ⅱ. The modified tailings are directly mixed with weathered materials. This mixing method is simple and efficient and can give full play to the advantages of the two raw materials.
[0059] III. The mixed material was subjected to a single-stage activation process, maintained at 105°C for 3 hours. During this process, the material developed a bimodal pore size distribution, with pores of 2 nm and 30 nm in diameter. This bimodal pore size distribution can simultaneously meet the adsorption requirements for both small and large molecular pollutants, improving the material's broad-spectrum adsorption.
[0060] Example 4: This example is an application of the tailings-based low-temperature responsive sewage adsorption material in Example 1, 2, or 3 in sewage treatment. The following is an illustration of the actual application of the sewage adsorption material in a rural sewage treatment station:
[0061] · 1. Scene characteristics:
[0062] · The average daily treatment capacity of the rural sewage treatment station is 50m 3 In winter, water temperatures range from -15°C to 5°C, and influent COD fluctuates between 150 and 400 mg / L. This intermittent high-load scenario places high demands on the performance of wastewater treatment materials. Low temperatures reduce the material's adsorption efficiency, while fluctuations in influent COD require the material to quickly adapt to varying pollutant loads.
[0063] ·2. Application effect:
[0064] · Water quality compliance: After 30 days of operation, the adsorption module achieved effluent COD ≤ 28 mg / L and TP ≤ 0.25 mg / L, achieving 100% compliance. This demonstrates that the adsorption material can effectively remove pollutants such as COD and total phosphorus from wastewater, ensuring that effluent quality meets relevant standards. The material also remained stable under low-temperature and high-load conditions, demonstrating its excellent performance and reliability.
[0065] · Cost Reduction: The material replacement cycle is six months, reducing annual treatment costs by 62% compared to activated carbon systems. While traditional activated carbon materials are relatively expensive, the adsorption material of this invention utilizes solid waste such as mine tailings and weathered materials, significantly reducing production costs. Furthermore, the material's extended service life reduces the frequency of material replacement, further reducing operating costs.
[0066] · Solid waste resource utilization: Each adsorption module consumes 1.2 tons of tailings, reducing the solid waste storage area by 0.36m 3 This not only solves the land occupation and environmental safety issues caused by the storage of mine tailings, but also realizes the resource utilization of tailings, which is in line with the concept of green development. By converting tailings into efficient sewage treatment materials, it achieves resource recycling and has significant environmental and economic benefits.
[0067] · Run result table
[0068]
[0069]
[0070] A comparison of operational results demonstrates that the adsorbent material of the present invention offers significant advantages in terms of raw material cost, low-temperature adsorption efficiency, adaptability to load fluctuations, and solid waste resource utilization. Compared to conventional activated carbon, the present material significantly reduces raw material cost, significantly improves low-temperature adsorption efficiency, and can adapt to a wider range of pollution load fluctuations while achieving efficient resource utilization of solid waste. This demonstrates that the adsorbent material of the present invention has broad application prospects and market competitiveness, providing a more economical, efficient, and environmentally friendly solution for wastewater treatment.
Claims
1. A tailings-based low-temperature responsive sewage adsorption material, characterized in that: include: Sand and gravel mine tailings, containing SiO2 and Fe2O3; The upper layer of weathered material contains kaolin and montmorillonite; Binders, used to bind the tailings and weathered material together; The SiO2 in the tailings can interact with the Al2O3 in the weathered material to form an [AlO4 / SiO4] tetrahedral network structure; the Fe2O3 in the tailings can produce Fe-O-Si bonding with the montmorillonite in the weathered material.
2. The tailings-based low-temperature responsive sewage adsorption material according to claim 1, characterized in that: The weight ratio of each component is: Sand and gravel mine tailings 40-65wt%; Upper layer weathered material 25-50wt%; Binder 5-10wt%.
3. The tailings-based low-temperature responsive sewage adsorption material according to claim 2, characterized in that: The proportion of upper weathered materials is adjusted according to the concentration of macromolecular pollutants in the treated wastewater. The higher the concentration of macromolecular pollutants, the higher the proportion of upper weathered materials.
4. The tailings-based low-temperature responsive sewage adsorption material according to claim 3, characterized in that: When COD in the treated sewage is ≤300mg / L, the proportion of weathered materials is 25-35%; When the COD in the treated wastewater is 300-500 mg / L, the proportion of weathered materials is 35-45%; When the COD in the treated sewage is ≥500 mg / L, the proportion of weathered materials is 45-50%.
5. The tailings-based low-temperature responsive sewage adsorption material according to claim 1, characterized in that: The binder is a sodium silicate solution.
6. A method for preparing the tailings-based low-temperature responsive sewage adsorption material according to any one of claims 1 to 5, characterized in that: include: Carry out hydrochloric acid activation treatment on sand and gravel mine tailings; The activated tailings are mixed with the weathered materials in a gradient process, and the mixing process is combined with ball milling; The mixed material was subjected to primary activation and maintained at a temperature of 95°C for 2.5 hours; After the primary activation, the secondary activation was carried out at a temperature of 115°C for 1.2 hours.
7. The preparation method according to claim 6, characterized in that The hydrochloric acid activation treatment of the sand and gravel mine tailings comprises: Soak in 4-6% hydrochloric acid solution for 45-60 minutes, with a solid-liquid ratio of 1:3-1:
5.
8. A method for preparing the tailings-based low-temperature responsive sewage adsorption material according to any one of claims 1 to 5, characterized in that: include: Alkali modification treatment of sand and gravel mine tailings; The modified tailings are directly mixed with the weathered material; The mixed material was subjected to a single-stage activation at a temperature of 105°C for 3 hours.
9. The preparation method according to claim 8, characterized in that The alkali modification treatment of the sand and gravel mine tailings comprises: Ultrasonic treatment was performed using 0.5-1 mol / L NaOH solution for 20-30 minutes.
10. Use of the tailings-based low-temperature responsive sewage adsorption material according to any one of claims 1 to 5 in sewage treatment.