Powder-modified non-clinker cement activator

Abstract

The application discloses a powder modified non-clinker cement activator and relates to the technical field of non-clinker cement.The application is composed of the following components with the weight percentage: 20-35% of alkaline activator, 15-25% of sulfate activator, 5-10% of novel organic activator, 2-8% of nanometer material, 1-5% of surfactant and 17-57% of filling agent; the alkaline activator is a compound of sodium hydroxide and sodium carbonate, and the compound mass ratio is 1:1.5-2.5. Through the mutual cooperation of the components of the multi-component compound formula, the application effectively solves the problem of limited activation effect of the traditional non-clinker cement activator. The alkaline, sulfate and novel organic activator jointly improve the strength, the nanometer material enhances the microstructure to improve the durability, and the surfactant optimizes the dispersibility, so that the non-clinker cement is significantly improved in the early and late strength, microstructure and durability, and the demand of modern building engineering on the high performance of the non-clinker cement is met.

Description

Technical Field

[0001] This invention belongs to the field of clinkerless cement technology, and in particular relates to powder-modified clinkerless cement activators. Background Technology

[0002] In the production of clinkerless cement, activators play a crucial role. They promote the hydration reaction of raw materials such as industrial waste, forming a cementitious material with a certain strength. Traditional clinkerless cement activators have been used in this field for a long time, realizing the production of clinkerless cement to a certain extent. This provides the building materials industry with a way to utilize industrial waste and, to some extent, meets the needs of some construction projects that do not have high requirements for strength and durability.

[0003] However, with the development of the construction industry, the performance requirements for clinkerless cement are increasing. Traditional activators are gradually becoming unable to meet the new demands. In terms of performance, traditional activators have limited activation effects and cannot fully activate the activity of industrial waste residue, resulting in slow early strength growth of clinkerless cement, which cannot meet the requirements of rapid construction progress. The later strength improvement is not significant, making it difficult to apply to building structures with high strength requirements. At the same time, the improvement on the microstructure of cement stone is not obvious, resulting in poor durability of clinkerless cement. In the long-term use, it is prone to cracking, strength reduction and other problems, affecting the service life of buildings. In terms of production, the production of traditional activators may lack standardized processes, the quality of each batch of products is unstable, and it is difficult to achieve large-scale production. Moreover, the synergistic effect between various components may not be fully considered, resulting in the inability of the activator performance to be fully realized.

[0004] To address these issues, we have developed a powder-modified clinker-free cement activator. Summary of the Invention

[0005] The purpose of this invention is to provide a powder-modified clinker-free cement activator. By combining a multi-component composite activating system, nanomaterials to enhance the microstructure, and surfactants to optimize particle dispersion, this invention solves the problems of limited activating effect, insufficient early and late strength, and poor durability of existing clinker-free cement activators.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution.

[0007] This invention relates to a powder-modified clinker-free cement activator, composed of the following components by weight percentage: 20%-35% alkaline activator, 15%-25% sulfate activator, 5%-10% novel organic activator, 2%-8% nanomaterials, 1%-5% surfactant, and 17%-57% filler; the alkaline activator is a compound of sodium hydroxide and sodium carbonate, with a compounding mass ratio of 1:1.5-2.5; the sulfate activator is a compound of calcium sulfate and sodium sulfate, with a compounding mass ratio of 2:1-3:1; the novel organic activator is a compound of triethanolamine and glycerol, with a compounding mass ratio of... The ratio of the components is 1:1 to 1:2; the nanomaterials are a mixture of nano-silica and nano-calcium carbonate with a mass ratio of 3:1 to 4:1; the surfactant is a polycarboxylic acid surfactant; the filler is talc powder with a particle size ≤100 mesh. Through a multi-component composite formula, alkaline activators, sulfate activators, novel organic activators, nanomaterials, surfactants, and fillers are compounded in specific proportions to achieve synergistic effects. This significantly improves the early and late strength of clinker-free cement, optimizes the microstructure, enhances durability, and comprehensively improves the performance of clinker-free cement, meeting the performance requirements of different projects for clinker-free cement.

[0008] The present invention further specifies that the polycarboxylic acid surfactant is a polycarboxylic acid-based high-efficiency water-reducing agent with a molecular weight of 20,000-50,000 and a solid content ≥40%, and its addition amount accounts for 80%-95% of the total mass of the surfactant. The remaining part is an auxiliary surfactant, which is sodium dodecylbenzene sulfonate. The polycarboxylic acid surfactant mainly uses a polycarboxylic acid-based high-efficiency water-reducing agent, supplemented by sodium dodecylbenzene sulfonate, and the molecular weight, solid content, and ratio are clearly defined. This selection and ratio design can better reduce the surface tension of particles and optimize the dispersibility of activators and industrial waste particles.

[0009] A method for producing powder-modified clinker-free cement activator includes the following steps: Step a: Pretreatment: Select alkaline activator, sulfate activator, novel organic activator, nanomaterials, surfactants, and fillers that meet the required proportions. Place each component separately into a drying device and dry at 80-105℃ for 2-3 hours to remove moisture from the material. After drying, remove the material and cool it to room temperature for later use. Perform pre-dispersion treatment on the nanomaterials by adding them to anhydrous ethanol and ultrasonically dispersing them for 30-40 minutes at an ultrasonic power of 200-300W. After dispersion, vacuum dry the nanomaterials to remove the anhydrous ethanol and obtain the pre-dispersed nanomaterials. Step b: Mixing of main activators: Place the pretreated alkaline activator and sulfate activator into a high-speed mixer, adjust the mixer speed to 800-1000 r / min, mix for 15-20 minutes to obtain a uniformly mixed mixture of main activators; Step c: Combining nanomaterials with the host activator: Slowly add the pre-dispersed nanomaterials obtained in S1 to the host activator mixture in S2, while adjusting the mixer speed to 1200-1500 r / min. Stir while adding, and mix for 25-35 minutes to ensure that the nanomaterials are uniformly dispersed in the host activator mixture, thus obtaining the nanocomposite activator intermediate. Step d: Addition of organic and surfactant: Add the pretreated novel organic activator and surfactant sequentially to the nanocomposite activator intermediate obtained in S3, keep the mixer speed at 1000-1200 r / min, and continue mixing for 20-25 minutes to fully integrate the organic, surfactant and intermediate to obtain crude composite activator; Step e: Filler mixing and pulverization: Add the pretreated filler to the crude composite activator obtained in S4, adjust the mixer speed to 800-1000 r / min, mix for 15-20 minutes to obtain a mixture; send the mixture into an ultrafine pulverizing device and pulverize to a particle size ≤ 800 mesh. During the pulverization process, control the internal temperature of the device to not exceed 60℃ to avoid organic failure due to high temperature. Step f: Modification treatment: Feed the crushed S5 material into the modifier, add 0.5%-1% of the total mass of the material as a modifier, adjust the temperature of the modifier to 60-85℃, the rotation speed to 500-800r / min, and modify for 20-40 minutes. The dispersibility and stability of the material are further optimized through the modification treatment. Step g: Finished product preparation: The S6 modified material is fed into a vibrating screening equipment and screened using an 800-mesh screen to remove uncrushed coarse particles. The material that passes through the screen is the finished product of powder modified clinker-free cement activator. The finished product is sent to a sterile packaging workshop and sealed in packaging. The packaging specifications are 25kg / bag or 50kg / bag. After packaging, it is stored in a warehouse. The storage environment should be kept dry and ventilated, and the temperature should be controlled between 5-35℃ to avoid moisture and clumping.

[0010] The present invention is further configured such that the drying equipment is a hot air circulating drying box, and a continuous ventilation mode is adopted during the drying process, with a ventilation rate of 1-1.5 m³ / h, to ensure that all components are dried evenly and the moisture content is reduced to below 0.5%. By using a hot air circulating drying box and setting a continuous ventilation mode and ventilation rate, it is possible to ensure that all components are dried evenly and effectively remove moisture to below 0.5%.

[0011] The present invention is further configured such that, during the pre-dispersion of nanomaterials in S1, the mass ratio of nanomaterials to anhydrous ethanol is 1:5-1:8, the solution temperature is controlled not to exceed 40°C during ultrasonic dispersion to prevent nanomaterials from agglomerating, the vacuum drying temperature is 70-80°C, and the drying time is 1-1.5 hours. By clearly defining the mass ratio of nanomaterials to anhydrous ethanol, the ultrasonic dispersion temperature, power, time, and vacuum drying conditions during pre-dispersion, the agglomeration of nanomaterials can be effectively prevented, and good pre-dispersion of nanomaterials can be achieved.

[0012] The invention is further configured such that the high-speed mixer is made of stainless steel, and the inner wall of the mixing chamber is polished to prevent materials from adhering to the chamber wall. During the mixing process, the machine is stopped every 5 minutes to check the mixing uniformity to ensure that all components are fully mixed. The high-speed mixer is made of stainless steel and the inner wall is polished to prevent materials from adhering. The mixing uniformity is checked regularly during the mixing process.

[0013] The present invention is further configured such that the ultrafine pulverizing equipment is an airflow pulverizer, and an inert gas is introduced for protection during the pulverizing process. The inert gas is nitrogen, and the gas flow rate is 2-3 m / s to prevent the material from oxidizing and deteriorating during the pulverizing process, while reducing dust pollution during the pulverizing process. Using an airflow pulverizer and introducing nitrogen for protection can prevent the material from oxidizing and deteriorating, reduce dust pollution, and control the pulverizing temperature to avoid organic failure.

[0014] The present invention is further configured such that the modifying agent is a silane coupling agent, specifically KH-550 type silane coupling agent. The dispersibility of the material is monitored in real time during the modification process. When the particle size distribution variation coefficient of the material is ≤0.2, the modification is stopped. Using KH-550 type silane coupling agent as the modifying agent and monitoring the material dispersibility in real time to control the modification process can more accurately optimize the dispersibility and stability of the material and improve the performance of the activator.

[0015] The present invention is further configured such that the vibrating screening equipment is an ultrasonic vibrating screen, and the ultrasonic power during the screening process is 100-150W to prevent screen blockage and improve screening efficiency; the coarse particles on the screen are returned to the ultrafine pulverizing equipment for re-pulverization to ensure that the particle size of the finished product meets the requirements. Using an ultrasonic vibrating screen and setting the ultrasonic power can prevent screen blockage and improve screening efficiency. The coarse particles on the screen are returned for re-pulverization to ensure that the particle size of the finished product is qualified.

[0016] The present invention is further configured such that the sealed packaging adopts a double-layer packaging structure, with the inner layer being a polyethylene film bag and the outer layer being a woven bag. Before packaging, the moisture content of the finished product is tested, and packaging is only permitted if the moisture content is ≤0.5%. The packaging opening adopts a double sealing method of heat sealing and rope binding to ensure a tight seal. The double-layer packaging structure and the double sealing method of heat sealing and rope binding, the moisture testing before packaging, and the control of temperature and humidity in the storage environment can effectively prevent the product from getting damp and clumping, ensure stable product quality, and extend the shelf life.

[0017] The present invention has the following beneficial effects.

[0018] 1. This invention effectively solves the problem of limited activation effect of traditional clinker-free cement activators by synergistically combining the various components of a multi-component composite formula. The combined action of alkalinity, sulfate, and novel organic activators enhances strength, nanomaterials strengthen the microstructure and improve durability, and surfactants optimize dispersibility. This results in significant improvements in early and late-stage strength, microstructure, and durability of clinker-free cement, meeting the high-performance requirements of modern construction engineering for clinker-free cement.

[0019] 2. This invention includes steps such as pretreatment, multi-step mixing, pre-dispersion, pulverization, modification, sieving and packaging. The process logic is clear and closely matches actual production. By precisely controlling the parameters of each step, the quality of the finished activator is ensured to be stable and the performance reliable. This invention achieves the standardization and large-scale production of activators and has good prospects for industrial application. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0021] Figure 1 This is the overall flow chart for powder-modified clinker-free cement activator.

[0022] Figure 2 This is a flowchart of the pretreatment process for powder-modified clinker-free cement activator.

[0023] Figure 3 This is a core composite process flow diagram for powder-modified clinker-free cement activators.

[0024] Figure 4 This is a flowchart of the crushing and modification process for powder-modified clinker-free cement activator.

[0025] Figure 5 Flowchart for the preparation and packaging of powder-modified clinker-free cement activator. Detailed Implementation

[0026] The technical solutions of the present invention will be described below with reference to the accompanying drawings. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0027] refer to Figures 1 to 5This powder-modified clinker-free cement activator is composed of: 20%-35% alkaline activator, 15%-25% sulfate activator, 5%-10% novel organic activator, 2%-8% nanomaterials, 1%-5% surfactant, and 17%-57% filler. The alkaline activator is a mixture of sodium hydroxide and sodium carbonate in a mass ratio of 1:1.5-2.5; the sulfate activator is a mixture of calcium sulfate and sodium sulfate in a mass ratio of 2:1-3:1; and the novel organic activator is a mixture of triethanolamine and glycerol. The compounding mass ratio is 1:1-1:2; the nanomaterial is a compound of nano-silica and nano-calcium carbonate, with a compounding mass ratio of 3:1-4:1; the surfactant is a polycarboxylic acid surfactant, which is a polycarboxylic acid-based high-efficiency water-reducing agent with a molecular weight of 20,000-50,000 and a solid content of ≥40%, and its addition accounts for 80%-95% of the total mass of the surfactant, with the remainder being an auxiliary surfactant, which is sodium dodecylbenzene sulfonate; the filler is talc powder with a particle size ≤100 mesh.

[0028] The activator adopts a multi-component composite formula, which is composed of alkaline activator, sulfate activator, novel organic activator, nanomaterials, surfactants and fillers in a specific ratio. The synergistic effect of each component can significantly improve the early and late strength of clinkerless cement, optimize its microstructure and improve its durability.

[0029] A method for producing powder-modified clinker-free cement activator includes the following steps: Step a: Pretreatment: Select alkaline activator, sulfate activator, novel organic activator, nanomaterials, surfactants, and fillers that meet the required proportions. Place each component separately into a drying device and dry at 80-105℃ for 2-3 hours to remove moisture from the material. After drying, remove and cool to room temperature for later use. The drying device is a hot air circulating drying box with continuous ventilation at a rate of 1-1.5 m³ / h to ensure uniform drying of each component and reduce the moisture content to below 0.5%. Pre-dispersion treatment of nanomaterials: Add nanomaterials to anhydrous ethanol and ultrasonically disperse for 30-40 minutes at an ultrasonic power of 200-300W. After dispersion, vacuum dry to remove anhydrous ethanol and obtain pre-dispersed nanomaterials. During pre-dispersion, the mass ratio of nanomaterials to anhydrous ethanol is 1:5-1:8. Control the solution temperature not to exceed 40℃ during ultrasonic dispersion to prevent nanomaterial agglomeration. Vacuum drying temperature is 70-80℃, and drying time is 1-1.5 hours. Step b: Mixing of main activators: Place the pretreated alkaline activator and sulfate activator into a high-speed mixer, adjust the mixer speed to 800-1000 r / min, and mix for 15-20 minutes to obtain a uniformly mixed mixture of main activators. The high-speed mixer is made of stainless steel, and the inner wall of the mixing chamber is polished to prevent materials from adhering to the chamber wall. During the mixing process, stop the machine every 5 minutes to check the mixing uniformity to ensure that each component is fully mixed. Step c: Combining nanomaterials with the host activator: Slowly add the pre-dispersed nanomaterials obtained in S1 to the host activator mixture in S2, while adjusting the mixer speed to 1200-1500 r / min. Stir while adding, and mix for 25-35 minutes to ensure that the nanomaterials are uniformly dispersed in the host activator mixture, thus obtaining the nanocomposite activator intermediate. Step d: Addition of organic and surfactant: Add the pretreated novel organic activator and surfactant sequentially to the nanocomposite activator intermediate obtained in S3, keep the mixer speed at 1000-1200 r / min, and continue mixing for 20-25 minutes to fully integrate the organic, surfactant and intermediate to obtain crude composite activator; Step e: Filler mixing and pulverization: Add the pretreated filler to the crude composite activator obtained in S4, adjust the mixer speed to 800-1000 r / min, mix for 15-20 minutes to obtain a mixture; send the mixture into an ultrafine pulverizing device and pulverize to a particle size ≤800 mesh. During the pulverization process, control the internal temperature of the device to not exceed 60℃ to avoid organic failure due to high temperature. The ultrafine pulverizing device is an airflow pulverizer. Inert gas is introduced during the pulverization process for protection. The inert gas is nitrogen, and the gas flow rate is 2-3 m / s to prevent the material from oxidizing and deteriorating during the pulverization process, while reducing dust pollution during the pulverization process. Step f: Modification treatment: Feed the crushed S5 material into a modifier, add 0.5%-1% of the total mass of the material as a modifier, adjust the temperature of the modifier to 60-85℃, the rotation speed to 500-800 r / min, and modify for 20-40 minutes. The modification treatment further optimizes the dispersibility and stability of the material. The modifier is a silane coupling agent, specifically KH-550 type silane coupling agent. During the modification process, the dispersibility of the material is monitored in real time. When the particle size distribution variation coefficient of the material is ≤0.2, the modification is stopped. Step g: Finished product preparation: The S6 modified material is fed into a vibrating screen and screened using an 800-mesh screen to remove uncrushed coarse particles. The material passing through the screen is the finished product of the powder-modified clinker-free cement activator. The vibrating screen is an ultrasonic vibrating screen with an ultrasonic power of 100-150W during the screening process to prevent screen blockage and improve screening efficiency. The coarse particles on the screen are returned to the ultrafine grinding equipment for re-grinding to ensure that the particle size of the finished product meets the requirements. The finished product is sent to the aseptic packaging workshop and sealed in 25kg / bag or 50kg / bag. After packaging, it is stored in a warehouse. The storage environment should be kept dry and ventilated, and the temperature should be controlled between 5-35℃ to avoid moisture and clumping. The sealed packaging adopts a double-layer packaging structure, with an inner polyethylene film bag and an outer woven bag. Before packaging, the moisture content of the finished product is tested. The moisture content must be ≤0.5% before packaging. The packaging opening adopts a double sealing method of heat sealing and rope binding to ensure a tight seal.

[0030] During the production process, materials at each step are sampled and tested. The mixing uniformity of the main activator mixture in step b, the intermediate nano-composite activator in step c, the crude composite activator in step d, the modified material in step f, and the finished product in step g must all be tested, with a mixing uniformity deviation of ≤5%. The activation activity of the finished product must also be tested to ensure that it can enable the clinker-free cement to achieve a 3-day compressive strength ≥15MPa, a 28-day compressive strength ≥35MPa, and durability indicators that meet the requirements of GB / T 3183-2017 standard.

[0031] The production method includes pretreatment, multi-step mixing, pre-dispersion, pulverization, modification, sieving and packaging. The process is logical and closely follows actual production. By precisely controlling the parameters of each step, the quality of the finished activator is ensured to be stable and the performance reliable. This achieves the standardization and large-scale production of activators and has good prospects for industrial application. Specific Implementation Example 1 A powder-modified clinker-free cement activator and its production method Formula for activator of powder-modified clinker-free cement (by weight percentage) The composition includes: 28% alkaline activator (sodium hydroxide:sodium carbonate = 1:2, mass ratio), 20% sulfate activator (calcium sulfate:sodium sulfate = 2.5:1, mass ratio), 7% novel organic activator (triethanolamine:glycerol = 1:1.5, mass ratio), 5% nanomaterials (nano silica:nano calcium carbonate = 3.5:1, mass ratio), 3% surfactant (85% polycarboxylate-based high-efficiency water-reducing agent, 15% sodium dodecylbenzenesulfonate), and 37% filler (talc, particle size ≤100 mesh); the total weight percentage is 100%.

[0033] Production methods Pretreatment: Select each of the above proportions and place them in a hot air circulating drying oven. Dry at 95℃ for 2.5 hours using continuous ventilation mode with a ventilation rate of 1.2 m³ / h. After drying, remove and cool to room temperature to ensure that the moisture content of each is reduced to below 0.5%. Pre-disperse the nanomaterials by mixing nanomaterials and anhydrous ethanol at a mass ratio of 1:6.5, ultrasonically disperse for 35 minutes at an ultrasonic power of 250W, and control the solution temperature to ≤35℃. After dispersion, vacuum dry at 75℃ for 1.2 hours to remove anhydrous ethanol and obtain pre-dispersed nanomaterials.

[0034] Mixing of main activators: Place the pretreated alkaline activator and sulfate activator into a high-speed mixer made of stainless steel with polished inner walls, adjust the speed to 900 r / min, mix for 18 minutes to obtain a uniform mixture of main activators, and stop the machine every 5 minutes to check the mixing uniformity.

[0035] Nanomaterials combined with host activator: The pre-dispersed nanomaterials are slowly added to the host activator mixture, the mixer speed is adjusted to 1350 r / min, and the mixture is stirred while adding the nanomaterials for 30 minutes to ensure uniform dispersion and obtain the nanocomposite activator intermediate.

[0036] Organic and surfactant addition: The pretreated novel organic activator and surfactant were added sequentially to the nanocomposite activator intermediate. The mixture was kept at 1100 r / min and continued to be mixed for 22 minutes to ensure that the components were fully integrated and to obtain the crude composite activator.

[0037] Filler mixing and pulverization: Add the pretreated filler to the crude composite activator, adjust the rotation speed to 900 r / min, mix for 18 minutes to obtain a mixture; send the mixture into an air jet mill, purge with nitrogen protection (gas flow rate 2.5 m / s), pulverize to a particle size ≤ 800 mesh, and control the internal temperature of the equipment ≤ 55℃.

[0038] Modification treatment: The pulverized material is fed into a modifier, and 0.8% of the total mass of the material is added with KH-550 silane coupling agent. The temperature is adjusted to 75℃, the rotation speed is 650r / min, and the modification is carried out for 30 minutes. The dispersibility is monitored in real time. The modification is stopped when the particle size distribution variation coefficient is ≤0.2.

[0039] Finished product preparation: The modified material is fed into an ultrasonic vibrating screen with an 800-mesh screen and an ultrasonic power of 120W. After screening, the coarse particles on the screen are returned to the air jet mill for re-crushing, and the material that passes through the screen is the finished product. After the finished product is tested and found to have a moisture content of ≤0.5%, it is packaged in double-layer sealed packaging (inner layer polyethylene film bag, outer layer woven bag), with heat sealing and rope binding for double sealing. The packaging specification is 25kg / bag, and it is stored in a dry, ventilated warehouse at a temperature of 20℃.

[0040] Performance test results The activator prepared in this embodiment, when used in the production of clinkerless cement, results in a 3-day compressive strength of 16.2 MPa, a 28-day compressive strength of 37.5 MPa, a mixing uniformity deviation of 4.2%, and durability indicators that meet the requirements of GB / T 3183-2017 standard, which is significantly better than traditional activators. Specific Implementation Example 2 A powder-modified clinker-free cement activator and its production method Formula for activator of powder-modified clinker-free cement (by weight percentage) Alkaline activator 20% (sodium hydroxide:sodium carbonate = 1:1.5, mass ratio), sulfate activator 25% (calcium sulfate:sodium sulfate = 3:1, mass ratio), novel organic activator 5% (triethanolamine:glycerol = 1:1, mass ratio), nanomaterials 8% (nano silica:nano calcium carbonate = 4:1, mass ratio), surfactant 5% (polycarboxylate-based high-efficiency water-reducing agent accounts for 95%, sodium dodecylbenzenesulfonate accounts for 5%), filler 37% (talc powder, particle size ≤100 mesh); the total weight percentage is 100%.

[0042] Production methods Pretreatment: Select each of the above proportions and place them in a hot air circulating drying oven. Dry at 80℃ for 3 hours using continuous ventilation mode with a ventilation rate of 1.0 m³ / h. After drying, remove and cool to room temperature to ensure that the moisture content of each is reduced to below 0.5%. Pre-disperse the nanomaterials by mixing nanomaterials and anhydrous ethanol at a mass ratio of 1:5 and ultrasonically dispersing for 40 minutes at an ultrasonic power of 200W. Control the solution temperature to ≤38℃. After dispersion, vacuum dry at 70℃ for 1.5 hours to remove anhydrous ethanol and obtain pre-dispersed nanomaterials.

[0043] Mixing of main activators: Place the pretreated alkaline activator and sulfate activator into a high-speed mixer made of stainless steel with polished inner walls, adjust the speed to 800 r / min, mix for 20 minutes to obtain a uniform mixture of main activators, and stop the machine every 5 minutes to check the mixing uniformity.

[0044] Nanomaterials combined with host activator: The pre-dispersed nanomaterials are slowly added to the host activator mixture, the mixer speed is adjusted to 1200 r / min, and the mixture is stirred while adding the nanomaterials for 35 minutes to ensure uniform dispersion and obtain the nanocomposite activator intermediate.

[0045] Organic and surfactant addition: The pretreated novel organic activator and surfactant were added sequentially to the nanocomposite activator intermediate. The mixture was kept at 1000 r / min and continued to be mixed for 25 minutes to ensure that the components were fully integrated, thus obtaining the crude composite activator.

[0046] Filler mixing and pulverization: Add the pretreated filler to the crude composite activator, adjust the rotation speed to 800 r / min, mix for 20 minutes to obtain a mixture; send the mixture into an air jet mill, purge with nitrogen for protection (gas flow rate 2.0 m / s), pulverize to a particle size ≤ 800 mesh, and control the internal temperature of the equipment ≤ 58℃.

[0047] Modification treatment: The pulverized material is fed into a modifier, and 0.5% of the total mass of the material is added with KH-550 silane coupling agent. The temperature is adjusted to 60℃, the rotation speed is 500r / min, and the modification is carried out for 40 minutes. The dispersibility is monitored in real time. The modification is stopped when the particle size distribution variation coefficient is ≤0.2.

[0048] Finished product preparation: The modified material is fed into an ultrasonic vibrating screen with an 800-mesh screen and an ultrasonic power of 100W. After screening, the coarse particles on the screen are returned to the air jet mill for re-crushing, and the material that passes through the screen is the finished product. After the moisture content of the finished product is tested to be ≤0.5%, it is packaged in double-layer sealed packaging (inner layer polyethylene film bag, outer layer woven bag), heat-sealed and tied with rope for double sealing, with a packaging specification of 50kg / bag, and stored in a dry, ventilated warehouse at a temperature of 15℃.

[0049] Performance test results The activator prepared in this embodiment, when used in the production of clinkerless cement, results in a 3-day compressive strength of 15.5 MPa, a 28-day compressive strength of 36.8 MPa, a mixing uniformity deviation of 4.7%, and durability indicators that meet the requirements of GB / T 3183-2017 standard. The activating effect is stable. Specific Implementation Example 3 A powder-modified clinker-free cement activator and its production method Formula for activator of powder-modified clinker-free cement (by weight percentage) The composition includes: 35% alkaline activator (sodium hydroxide:sodium carbonate = 1:2.5, mass ratio), 15% sulfate activator (calcium sulfate:sodium sulfate = 2:1, mass ratio), 10% novel organic activator (triethanolamine:glycerol = 1:2, mass ratio), 2% nanomaterials (nano silica:nano calcium carbonate = 3:1, mass ratio), 1% surfactant (80% polycarboxylate-based high-efficiency water-reducing agent, 20% sodium dodecylbenzenesulfonate), and 37% filler (talc, particle size ≤100 mesh); the total weight percentage is 100%.

[0051] Production methods Pretreatment: Select each of the above proportions and place them in a hot air circulating drying oven. Dry at 105℃ for 2 hours using continuous ventilation mode with a ventilation rate of 1.5m³ / h. After drying, remove and cool to room temperature to ensure that the moisture content of each is reduced to below 0.5%. Pre-disperse the nanomaterials by mixing nanomaterials and anhydrous ethanol at a ratio of 1:8 (mass ratio), ultrasonically disperse for 30 minutes at an ultrasonic power of 300W, and control the solution temperature to ≤40℃. After dispersion, vacuum dry at 80℃ for 1.0 hour to remove anhydrous ethanol and obtain pre-dispersed nanomaterials.

[0052] Mixing of main activators: Place the pretreated alkaline activator and sulfate activator into a high-speed mixer made of stainless steel with polished inner walls, adjust the speed to 1000 r / min, mix for 15 minutes to obtain a uniform mixture of main activators, and stop the machine every 5 minutes to check the mixing uniformity.

[0053] Nanomaterials combined with host activator: The pre-dispersed nanomaterials are slowly added to the host activator mixture, the mixer speed is adjusted to 1500 r / min, and the mixture is stirred while adding the nanomaterials for 25 minutes to ensure uniform dispersion and obtain the nanocomposite activator intermediate.

[0054] Organic and surfactant addition: The pretreated novel organic activator and surfactant were added sequentially to the nanocomposite activator intermediate. The mixture was kept at 1200 r / min and continued to be mixed for 20 minutes to ensure that the components were fully integrated, thus obtaining the crude composite activator.

[0055] Filler mixing and pulverization: Add the pretreated filler to the crude composite activator, adjust the rotation speed to 1000 r / min, mix for 15 minutes to obtain a mixture; send the mixture into an air jet mill, purge with nitrogen for protection (gas flow rate 3.0 m / s), pulverize to a particle size ≤ 800 mesh, and control the internal temperature of the equipment ≤ 52℃.

[0056] Modification treatment: The pulverized material is fed into a modifier, and 1.0% of the total mass of the material is added with KH-550 silane coupling agent. The temperature is adjusted to 85℃, the rotation speed is 800r / min, and the modification is carried out for 20 minutes. The dispersibility is monitored in real time. The modification is stopped when the particle size distribution variation coefficient is ≤0.2.

[0057] Finished product preparation: The modified material is fed into an ultrasonic vibrating screen with an 800-mesh screen and an ultrasonic power of 150W. After screening, the coarse particles on the screen are returned to the air jet mill for re-crushing, and the material that passes through the screen is the finished product. After the finished product is tested and found to have a moisture content of ≤0.5%, it is packaged in double-layer sealed packaging (inner layer polyethylene film bag, outer layer woven bag), with heat sealing and rope binding for double sealing. The packaging specification is 25kg / bag, and it is stored in a dry, ventilated warehouse at a temperature of 30℃.

[0058] Performance test results The activator prepared in this embodiment, when used in the production of clinkerless cement, results in a 3-day compressive strength of 17.1 MPa, a 28-day compressive strength of 38.2 MPa, a mixing uniformity deviation of 3.8%, and durability indicators that meet the requirements of GB / T 3183-2017 standard, demonstrating a significant early strength improvement effect.

[0059] Analysis of the differences in the implementation examples and the impact of variables on the results 1. Influence of the proportion of formulation components Alkaline / sulfate activators: The two are mixed in reverse ratio. The higher the proportion of alkaline activator, the stronger the early strength (Example 3 is the best); the higher the proportion of sulfate, the more stable the later strength (Example 2 is the best). The ratio in Example 1 is balanced and has the best overall performance.

[0060] Organic activator / nanomaterials: The two are mixed in reverse ratios. The higher the proportion of organic activator, the better the mixing uniformity (the best result is shown in Example 3). Nanomaterials can compensate for insufficient mixing uniformity and improve the later strength (as demonstrated in Example 2).

[0061] Surfactants: The higher the proportion of polycarboxylic acid surfactants and the more moderate the total amount added, the better the dispersibility. The ratio in Example 1 is optimal, balancing performance and cost.

[0062] 2. Influence of process parameters Drying / Pre-dispersion: High-temperature short-time drying and high-power short-time ultrasonication can reduce nano-agglomeration and improve uniformity (Example 3 is the best).

[0063] Mixing / Pulverizing: High-speed short-time mixing and high-nitrogen gas flow rate low-temperature pulverization can improve uniformity and avoid component failure (Example 3 is the best).

[0064] Modification: High temperature, high speed, and high additive dosage can shorten the modification time and optimize the dispersibility (Example 3 is the best). Example 1 has the best cost performance due to parameter balance.

[0065] 3. Overall Conclusion Example 1 has the best overall performance, balancing early and late-stage strength and cost; Example 3 focuses on early-stage strength and is suitable for corresponding scenarios; Example 2 focuses on late-stage stability and is adapted to long-term use requirements.

[0066] The preferred embodiments of the present invention disclosed above are only for the purpose of illustrating the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation described herein. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can better understand and utilize the present invention.

Claims

1. A powder-modified clinker-free cement activator, characterized in that: It is composed of the following components by weight percentage: 20%-35% alkaline activator, 15%-25% sulfate activator, 5%-10% novel organic activator, 2%-8% nanomaterials, 1%-5% surfactant, and 17%-57% filler; the alkaline activator is a compound of sodium hydroxide and sodium carbonate with a mass ratio of 1:1.5-2.5; the sulfate activator is a compound of calcium sulfate and sodium sulfate with a mass ratio of 2:1-3:1; the novel organic activator is a compound of triethanolamine and glycerol with a mass ratio of 1:1-1:2; the nanomaterials are a compound of nano-silica and nano-calcium carbonate with a mass ratio of 3:1-4:1; the surfactant is a polycarboxylic acid surfactant; and the filler is talc with a particle size ≤100 mesh.

2. The powder-modified clinker-free cement activator according to claim 1, characterized in that: The polycarboxylic acid surfactant is a polycarboxylic acid-based high-efficiency water-reducing agent with a molecular weight of 20,000-50,000 and a solid content of ≥40%. Its addition amount accounts for 80%-95% of the total mass of the surfactant, and the remaining part is an auxiliary surfactant, which is sodium dodecylbenzene sulfonate.

3. A method for producing powder-modified clinker-free cement activator as described in claim 1, characterized in that: Includes the following steps: Step a: Pretreatment: Select alkaline activator, sulfate activator, novel organic activator, nanomaterials, surfactants, and fillers that meet the required proportions. Place each component separately into a drying device and dry at 80-105℃ for 2-3 hours to remove moisture from the material. After drying, remove the material and cool it to room temperature for later use. Perform pre-dispersion treatment on the nanomaterials by adding them to anhydrous ethanol and ultrasonically dispersing them for 30-40 minutes at an ultrasonic power of 200-300W. After dispersion, vacuum dry the nanomaterials to remove the anhydrous ethanol and obtain the pre-dispersed nanomaterials. Step b: Mixing of main activators: Place the pretreated alkaline activator and sulfate activator into a high-speed mixer, adjust the mixer speed to 800-1000 r / min, mix for 15-20 minutes to obtain a uniformly mixed mixture of main activators; Step c: Combining nanomaterials with the host activator: Slowly add the pre-dispersed nanomaterials obtained in S1 to the host activator mixture in S2, while adjusting the mixer speed to 1200-1500 r / min. Stir while adding, and mix for 25-35 minutes to ensure that the nanomaterials are uniformly dispersed in the host activator mixture, thus obtaining the nanocomposite activator intermediate. Step d: Addition of organic and surfactant: Add the pretreated novel organic activator and surfactant sequentially to the nanocomposite activator intermediate obtained in S3, keep the mixer speed at 1000-1200 r / min, and continue mixing for 20-25 minutes to fully integrate the organic, surfactant and intermediate to obtain crude composite activator; Step e: Filler mixing and pulverization: Add the pretreated filler to the crude composite activator obtained in S4, adjust the mixer speed to 800-1000 r / min, mix for 15-20 minutes to obtain a mixture; send the mixture into an ultrafine pulverizing device and pulverize to a particle size ≤ 800 mesh. During the pulverization process, control the internal temperature of the device to not exceed 60℃ to avoid organic failure due to high temperature. Step f: Modification treatment: Feed the crushed S5 material into the modifier, add 0.5%-1% of the total mass of the material as a modifier, adjust the temperature of the modifier to 60-85℃, the rotation speed to 500-800r / min, and modify for 20-40 minutes. The dispersibility and stability of the material are further optimized through the modification treatment. Step g: Finished product preparation: The S6 modified material is fed into a vibrating screening equipment and screened using an 800-mesh screen to remove uncrushed coarse particles. The material that passes through the screen is the finished product of powder modified clinker-free cement activator. The finished product is sent to a sterile packaging workshop and sealed in packaging with a packaging specification of 25kg / bag or 50kg / bag. After packaging, it is stored in a warehouse. The storage environment should be kept dry and ventilated, and the temperature should be controlled between 5-35℃ to avoid moisture and clumping.

4. The production method of the powder-modified clinker-free cement activator according to claim 3, characterized in that: The drying equipment is a hot air circulating drying box. During the drying process, a continuous ventilation mode is adopted with a ventilation rate of 1-1.5 m³ / h to ensure that all components are dried evenly and the moisture content is reduced to below 0.5%.

5. The production method of the powder-modified clinker-free cement activator according to claim 3, characterized in that: During the pre-dispersion of nanomaterials in S1, the mass ratio of nanomaterials to anhydrous ethanol is 1:5-1:

8. During ultrasonic dispersion, the solution temperature is controlled to not exceed 40°C to prevent nanomaterials from agglomerating. The vacuum drying temperature is 70-80°C, and the drying time is 1-1.5 hours.

6. The production method of the powder-modified clinker-free cement activator according to claim 3, characterized in that: The high-speed mixer is made of stainless steel and the inner wall of the mixing chamber is polished to prevent materials from adhering to the chamber wall. During the mixing process, the machine is stopped every 5 minutes to check the mixing uniformity and ensure that all components are fully mixed.

7. The production method of the powder-modified clinker-free cement activator according to claim 3, characterized in that: The ultrafine pulverizing equipment is an airflow pulverizer. During the pulverizing process, an inert gas is introduced for protection. The inert gas is nitrogen, and the gas flow rate is 2-3 m / s. This prevents the material from oxidizing and deteriorating during the pulverizing process, while also reducing dust pollution during the pulverizing process.

8. The production method of the powder-modified clinker-free cement activator according to claim 3, characterized in that: The modifying agent is a silane coupling agent, specifically KH-550 type silane coupling agent. During the modification process, the dispersibility of the material is monitored in real time. When the particle size distribution variation coefficient of the material is ≤0.2, the modification is stopped.

9. The production method of the powder-modified clinker-free cement activator according to claim 3, characterized in that: The vibrating screening equipment is an ultrasonic vibrating screen. During the screening process, the ultrasonic power is 100-150W to prevent screen blockage and improve screening efficiency. Coarse particles on the screen are returned to the ultrafine grinding equipment for re-grinding to ensure that the particle size of the finished product meets the requirements.

10. The production method of the powder-modified clinker-free cement activator according to claim 3, characterized in that: The sealed packaging adopts a double-layer packaging structure, with an inner layer of polyethylene film bag and an outer layer of woven bag. Before packaging, the moisture content of the finished product is tested, and packaging can only proceed if the moisture content is ≤0.5%. The packaging opening adopts a double sealing method of heat sealing and rope binding to ensure a tight seal.

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