Method for inhibiting the setting and improving the activity of granulated electric furnace phosphorus slag powder

Abstract

The present application relates to the technical field of concrete mineral admixtures, and particularly discloses a method for inhibiting the setting of granulated electric furnace phosphorus slag powder and improving the activity, which comprises the step of using a modifier in the preparation of modified phosphorus slag powder; the modifier comprises modifier A and modifier B; the modifier A comprises the following mass fraction ratios of effective components: 28 parts of calcium nitrite, 5-15 parts of a modified chelating agent, and 0.08-0.30 parts of calcium hydroxide; the modified chelating agent comprises diethanol monoisopropanolamine; and the modifier B comprises industrial sodium silicate powder. The method has the following advantages: 1) the activity index of cement-based materials mixed with granulated electric furnace phosphorus slag can be significantly improved, and the setting time can be effectively shortened; and 2) the setting inhibition and activity improvement can be achieved by precisely controlling the phosphorus slag particle grinding process in the phosphorus slag powder production process, and the application problem of granulated electric furnace phosphorus slag in cement-based materials can be solved from the source without relying on the adjustment of the admixture in the concrete preparation stage.

Description

Technical Field

[0001] This invention relates to the field of concrete mineral admixture technology, and in particular to the field of granulated electric furnace phosphorus slag powder modification technology. Background Technology

[0002] my country is a core production area for the global yellow phosphorus industry. For every ton of yellow phosphorus produced, 8-10 tons of granulated electric arc furnace (EAF) phosphorus slag are generated. Industry statistics show that my country's annual emissions of granulated EAF phosphorus slag exceed 30 million tons. Currently, the core area for the utilization of granulated EAF phosphorus slag resources is concentrated in the cement-based materials industry. After high-temperature melting and water quenching, it forms a glassy structure with good potential hydration activity. It can be used as an auxiliary cementitious material to replace part of the cement and is widely used in various building materials such as concrete and mortar. This is the main way to utilize granulated EAF phosphorus slag resources. For example, in large-scale hydropower projects in Southwest China, the amount of granulated EAF phosphorus slag powder can reach 20%-60% of the total cementitious material, which not only reduces project costs but also realizes the resource utilization of solid waste, becoming an important source of green auxiliary materials in the cement-based materials field.

[0003] However, the soluble phosphorus and fluorine in granulated electric furnace slag form insoluble calcium phosphate and calcium fluoride in the cement slurry phase during the initial stage of cement hydration. These deposit on the surface of cement particles, forming a dense coating that hinders the contact between water molecules and cement minerals, resulting in a retarding effect in building materials containing granulated electric furnace slag. Generally, when the content of granulated electric furnace slag powder exceeds 15%, the setting time of cement-based materials will be significantly prolonged. This retarding effect not only extends the construction cycle but also affects the hardening performance of cement-based materials at low temperatures. Especially in building construction and municipal engineering projects with high requirements for construction progress, the application of granulated electric furnace slag powder is strictly limited, greatly restricting its resource utilization efficiency. Therefore, the further promotion and application of granulated electric furnace slag in cement-based materials is limited by its significant retarding characteristics.

[0004] To address the retarding problem of granulated electric furnace phosphorus slag, existing conventional solutions mainly rely on adding chemical admixtures during concrete production and construction, such as aluminum sulfate and calcium chloride, which are accelerators for setting and early strength. While this method can shorten setting time to some extent, it has significant drawbacks: First, accelerators like aluminum sulfate rapidly generate ettringite, leading to a rapid loss of fluidity in the concrete mixture and affecting workability. Second, during on-site construction, the admixture dosage needs to be adjusted in real time according to raw material fluctuations. However, most small and medium-sized projects lack precise testing equipment and professional technicians, making it difficult to accurately control the admixture dosage. This can easily result in over-addition leading to strength reduction later on, or under-addition failing to alleviate the retarding problem. Third, some admixtures (such as calcium chloride) accelerate steel corrosion and are unsuitable for reinforced concrete structures, limiting their applicability. Summary of the Invention

[0005] To address the problems of high retarding and low activity in existing granulated electric furnace phosphorus slag, as well as the issues of reliance on on-site additives leading to reduced workability, reduced strength in later stages, and the inability of under-addition to alleviate retarding, and the narrow applicability of additives, this invention provides a method for inhibiting the retarding of granulated electric furnace phosphorus slag powder and improving its activity.

[0006] The technical solution adopted in this invention is: a method for inhibiting the slow coagulation of granulated electric furnace phosphorus slag powder and improving its activity, including the step of using a modifier in the preparation process of modified phosphorus slag powder; the modifier includes modifier A and modifier B; modifier A includes the following effective components in the following mass proportions: 28 parts calcium nitrite, 5-15 parts modified chelating agent, and 0.08-0.30 parts calcium hydroxide; the modified chelating agent includes diethanol monoisopropanolamine; and modifier B includes industrial sodium silicate powder.

[0007] As will be readily understood by those skilled in the art, the “granulated electric furnace phosphorus slag” mentioned in this invention refers to a byproduct generated during the production of yellow phosphorus by the electric furnace method, which forms glassy particles after water quenching and rapid cooling, and does not refer to all phosphorus-containing waste slag.

[0008] As a further improvement of the present invention, the modified chelating agent is composed of diethanol monoisopropanolamine and triethanolamine in a mass ratio of 1:2 to 3.

[0009] The method of the present invention can be implemented according to the following steps:

[0010] S1. Prepare the modifier; wherein modifier A is prepared as a liquid and modifier B is a solid powder;

[0011] S2. Before the granulated electric furnace phosphorus slag enters the grinding device, modifier A is sprayed on the surface of the granulated electric furnace phosphorus slag. The amount of modifier A sprayed is 1‰ to 3‰ of the mass of the granulated electric furnace phosphorus slag, so as to obtain pretreated phosphorus slag.

[0012] S3. Grind the pretreated phosphorus slag using a grinding device to obtain ground phosphorus slag;

[0013] S4. Add modifier B to the pulverized phosphorus slag and mix evenly. The amount of modifier B added is 1‰ to 3‰ of the mass of the pulverized phosphorus slag, to obtain modified phosphorus slag powder.

[0014] In the above specific implementation scheme, when preparing improver A, the mass ratio of the effective component of improver A to water is preferably 1:1.2 to 2.5.

[0015] In this invention, the industrial sodium silicate powder should meet the following requirements: fineness <100μm and modulus of 1-3. The above-mentioned industrial sodium silicate powder can be prepared by pre-grinding to ensure that modifier B can be uniformly mixed with the phosphorus slag particles, avoiding agglomeration. The above-mentioned modulus range ensures its reactivity with the phosphorus slag particles during subsequent grinding.

[0016] To ensure a more uniform mixing of modifier A with the granulated electric furnace phosphate slag, modifier A can be atomized and sprayed using an atomizing spraying device. Those skilled in the art can choose existing atomizing spraying devices, such as the atomizing spraying system disclosed in Chinese Utility Model Patent ZL 202323103326.0 or similar devices. Spraying can be performed during the conveyor belt transport process before the granulated electric furnace phosphate slag enters the grinding device (e.g., a slag vertical mill). At this time, atomization spraying can achieve uniform coverage of modifier A on the surface of the phosphate slag particles, ensuring sufficient interaction between modifier A and the phosphate slag particles during subsequent grinding.

[0017] As a preferred embodiment, the pulverized phosphorus slag in the above specific implementation scheme should meet the following requirements: the proportion of particles with a particle size <2μm ≤10%, d 50 ≤12μm, d 90 ≤25μm, specific surface area of ​​400~500m² 2 / kg. This method ensures good activity of the phosphate slag while controlling the content of ultrafine phosphate slag powder, thus mitigating its adverse effects on retarding. Those skilled in the art can choose existing grinding equipment to grind the pretreated phosphate slag, as long as the above parameters are met. For example, a vertical mill integrating drying, grinding, and air classification can be used.

[0018] After grinding, modifier B needs to be added to the ground phosphorus slag and mixed evenly. This step can be added after grinding with a vertical mill and collecting the phosphorus slag with a dust collector, and before it is transported to the finished product warehouse. To accurately control the amount added, a powder quantitative addition device can be used, such as the powder quantitative addition device for powder silo system disclosed in utility model patent ZL202420269504.2.

[0019] The present invention also discloses a modified phosphorus slag powder, which is prepared by the method of the present invention for inhibiting the slow coagulation and improving the activity of granulated electric furnace phosphorus slag powder.

[0020] The present invention also discloses a method for preparing a cement-based material, characterized in that the raw material formulation includes the modified phosphorus slag powder of the present invention.

[0021] The present invention also discloses a cement-based building material, which is prepared by the method of the present invention.

[0022] The beneficial effects of this invention are: 1) Experiments show that the method of this invention can significantly improve the activity index of cement-based materials with added granulated electric furnace phosphorus slag and effectively shorten its setting time; 2) In the phosphorus slag powder production process, this invention achieves retardation inhibition and activity enhancement by implementing precise control during the grinding of phosphorus slag particles. This process does not require on-site adjustment of admixtures during the concrete preparation stage and can directly produce phosphorus slag powder products with low retardation and high activity, thus solving the application problem of granulated electric furnace phosphorus slag in cement-based materials from the source. Detailed Implementation

[0023] The present invention will be further described below with reference to embodiments.

[0024] Example 1:

[0025] Modified phosphate slag powder was prepared according to the following method:

[0026] (1) Preparation of the modified agent A: Measure each effective component according to the following mass ratio: 28 parts calcium nitrite, 10 parts modified chelating agent, and 0.25 parts calcium hydroxide; wherein the modified chelating agent is composed of diethanolamine monoisopropanolamine and triethanolamine in a mass ratio of 1:2.5. Then add water to prepare a liquid reagent, with the mass ratio of effective component to water being 1:1.63.

[0027] Preparation of Modifier B: Industrial sodium silicate powder is prepared by pre-grinding to meet the requirements of fineness <100μm and modulus of 2.

[0028] (2) During the conveyor belt conveying process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply modifier A to the surface of the phosphorus slag, with a dosage of 2‰ of the mass of the granulated electric furnace phosphorus slag, to obtain pretreated phosphorus slag.

[0029] (3) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 8.7%. 50 =10.3μm, d 90 =19.7μm, specific surface area 442m² 2 / kg, yielding pulverized phosphorus slag.

[0030] (4) Modifier B is added to the pulverized phosphate slag using a powder additive quantitative addition device before it is transported to the finished product warehouse after the slag has been ground in a vertical mill and collected by a dust collector. The amount added is 3‰ of the mass of the pulverized phosphate slag. Then it is transported to the finished product warehouse by a bucket elevator to obtain modified phosphate slag powder.

[0031] Example 2:

[0032] Modified phosphate slag powder was prepared according to the following method:

[0033] (1) Preparation of the improver A: Measure each effective component according to the following mass ratio: 28 parts calcium nitrite, 12 parts improved chelating agent, and 0.25 parts calcium hydroxide; wherein the improved chelating agent is composed of diethanolamine monoisopropanolamine and triethanolamine in a mass ratio of 1:2. Then add water to prepare a liquid reagent, with the mass ratio of effective component to water being 1:1.51.

[0034] Preparation of Modifier B: Industrial sodium silicate powder is prepared by pre-grinding to meet the requirements of fineness <100μm and modulus of 2.5.

[0035] (2) During the conveyor belt conveying process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply modifier A to the surface of the phosphorus slag, with a dosage of 1.5‰ of the mass of the granulated electric furnace phosphorus slag, to obtain pretreated phosphorus slag.

[0036] (3) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 8.4%. 50 =11.3μm, d 90 =20.7μm, specific surface area 467m² 2 / kg, yielding pulverized phosphorus slag.

[0037] (4) Modifier B is added to the pulverized phosphate slag using a powder additive quantitative addition device before it is transported to the finished product warehouse after the slag has been ground in a vertical mill and collected by a dust collector. The amount added is 2.5‰ of the mass of the pulverized phosphate slag. Then it is transported to the finished product warehouse by a bucket elevator to obtain modified phosphate slag powder.

[0038] Example 3:

[0039] Modified phosphate slag powder was prepared according to the following method:

[0040] (1) Preparation of the modified agent A: Measure each effective component according to the following mass ratio: 28 parts calcium nitrite, 9 parts modified chelating agent, and 0.21 parts calcium hydroxide; wherein the modified chelating agent is composed of diethanolamine monoisopropanolamine and triethanolamine in a mass ratio of 1:3. Then add water to prepare a liquid reagent, with the mass ratio of effective component to water being 1:1.70.

[0041] Preparation of Modifier B: Industrial sodium silicate powder is prepared by pre-grinding to meet the requirements of fineness <100μm and modulus of 2.5.

[0042] (2) During the conveyor belt conveying process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply modifier A to the surface of the phosphorus slag, with a dosage of 2.5‰ of the mass of the granulated electric furnace phosphorus slag, to obtain pretreated phosphorus slag.

[0043] (3) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 9.1%. 50 =10.7μm, d 90 =21.4μm, specific surface area 429m² 2 / kg, yielding pulverized phosphorus slag.

[0044] (4) Modifier B is added to the pulverized phosphate slag using a powder additive quantitative addition device before it is transported to the finished product warehouse after the slag has been ground in a vertical mill and collected by a dust collector. The amount added is 2‰ of the mass of the pulverized phosphate slag. Then it is transported to the finished product warehouse by a bucket elevator to obtain modified phosphate slag powder.

[0045] Comparative Example 1:

[0046] This comparative example was carried out under the same steps and conditions as Example 1, and all raw materials were from the same batch. The difference was that the particle size of the phosphorus slag was not optimized and no modifier was added. The specific scheme is as follows:

[0047] (1) After the granulated electric furnace phosphorus slag is dried, it enters the ball mill for grinding, which is a grinding equipment with a certain number of steel balls as grinding media.

[0048] (2) Grind the phosphorus slag to 380m using a ball mill. 2 Unmodified phosphorus slag powder was obtained by measuring the specific surface area per kg.

[0049] Comparative Example 2:

[0050] This comparative example serves as a control experiment for Example 1, conducted according to the same steps and conditions as Example 1, using the same batch of raw materials. The difference lies in the absence of a modifier. The specific procedure is as follows:

[0051] (1) During the conveyor belt conveying process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply water of the same amount as in Example 1 to the surface of the phosphorus slag, with an admixture amount of 2‰ of the mass of the granulated electric furnace phosphorus slag, to obtain pretreated phosphorus slag.

[0052] (2) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 8.8%. 50 =10.1μm, d 90 =19.3μm, specific surface area 446m² 2 / kg, to obtain pulverized phosphorus slag. Then it is transported to the finished product warehouse by bucket elevator, thus obtaining phosphorus slag powder without the addition of modifier.

[0053] Comparative Example 3:

[0054] This comparative example serves as a control experiment for Example 1, conducted according to the same steps and conditions as Example 1, using the same batch of raw materials. The difference lies in the use of only modifier A. The specific scheme is as follows:

[0055] (1) Preparation of the modified agent A: Measure each effective component according to the following mass ratio: 28 parts calcium nitrite, 10 parts modified chelating agent, and 0.25 parts calcium hydroxide; wherein the modified chelating agent is composed of diethanolamine monoisopropanolamine and triethanolamine in a mass ratio of 1:2.5. Then add water to prepare a liquid reagent, with the mass ratio of effective component to water being 1:1.63.

[0056] (2) During the conveyor belt conveying process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply modifier A to the surface of the phosphorus slag, with a dosage of 2‰ of the mass of the granulated electric furnace phosphorus slag, to obtain pretreated phosphorus slag.

[0057] (3) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 8.7%. 50 =10.3μm, d 90 =19.7μm, specific surface area 442m² 2 / kg, to obtain pulverized phosphorus slag. Then, it is transported to the finished product warehouse by a bucket elevator to obtain modified phosphorus slag powder.

[0058] Comparative Example 4:

[0059] This comparative example serves as a control experiment for Example 1, conducted according to the same steps and conditions as Example 1, using the same batch of raw materials. The difference lies in the use of only modifier B. The specific scheme is as follows:

[0060] (1) Preparation of modifier B: Industrial sodium silicate powder is prepared by pre-grinding to meet the requirements of fineness <100μm and modulus 2.

[0061] (2) During the conveyor belt transport process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply an amount of water equal to that in Example 1 to the surface of the phosphorus slag to obtain pretreated phosphorus slag.

[0062] (3) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 8.8%. 50 =10.1μm, d 90 =19.3μm, specific surface area 446m² 2 / kg, yielding pulverized phosphorus slag.

[0063] (4) Modifier B is added to the pulverized phosphate slag using a powder additive quantitative addition device before it is transported to the finished product warehouse after the slag has been ground in a vertical mill and collected by a dust collector. The amount added is 3‰ of the mass of the pulverized phosphate slag. Then it is transported to the finished product warehouse by a bucket elevator to obtain modified phosphate slag powder.

[0064] Comparative Example 5:

[0065] This comparative example is a control experiment of Example 1, conducted according to the same steps and conditions as Example 1, using the same batch of raw materials. The difference is that only diethanol monoisopropanolamine is used as the modified chelating agent, while maintaining the total proportion of the modified chelating agent unchanged. The specific scheme is as follows:

[0066] (1) Preparation of the modified agent A: Measure each effective component according to the following mass ratio: 28 parts calcium nitrite, 10 parts modified chelating agent (diethanol monoisopropanolamine), and 0.25 parts calcium hydroxide. Then add water to prepare a liquid reagent, with the mass ratio of effective component to water being 1:1.63.

[0067] Preparation of Modifier B: Industrial sodium silicate powder is prepared by pre-grinding to meet the requirements of fineness <100μm and modulus of 2.

[0068] (2) During the conveyor belt conveying process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply modifier A to the surface of the phosphorus slag, with a dosage of 2‰ of the mass of the granulated electric furnace phosphorus slag, to obtain pretreated phosphorus slag.

[0069] (3) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 8.5%. 50 =10.2μm, d 90 =19.3μm, specific surface area 447m² 2 / kg, yielding pulverized phosphorus slag.

[0070] (4) Modifier B is added to the pulverized phosphate slag using a powder additive quantitative addition device before it is transported to the finished product warehouse after the slag has been ground in a vertical mill and collected by a dust collector. The amount added is 3‰ of the mass of the pulverized phosphate slag. Then it is transported to the finished product warehouse by a bucket elevator to obtain modified phosphate slag powder.

[0071] Comparative Example 6:

[0072] This comparative example is a control experiment of Example 1, conducted according to the same steps and conditions as Example 1, using the same batch of raw materials. The difference is that only triethanolamine is used as the modified chelating agent, while maintaining the total proportion of the modified chelating agent unchanged. The specific scheme is as follows:

[0073] (1) Preparation of the modified agent A: Measure each effective component according to the following mass ratio: 28 parts calcium nitrite, 10 parts modified chelating agent (triethanolamine), and 0.25 parts calcium hydroxide. Then add water to prepare a liquid reagent, with the mass ratio of effective component to water being 1:1.63.

[0074] Preparation of Modifier B: Industrial sodium silicate powder is prepared by pre-grinding to meet the requirements of fineness <100μm and modulus of 2.

[0075] (2) During the conveyor belt conveying process before the granulated electric furnace phosphorus slag enters the grinding mill (slag vertical mill), an atomizing spray device is used to apply modifier A to the surface of the phosphorus slag, with a dosage of 2‰ of the mass of the granulated electric furnace phosphorus slag, to obtain pretreated phosphorus slag.

[0076] (3) A vertical mill integrating drying, grinding, and air classification was used to grind the pretreated phosphorus slag until the particle size <2μm accounted for 8.7%. 50 =10.4μm, d 90 =19.5μm, specific surface area 451m² 2 / kg, yielding pulverized phosphorus slag.

[0077] (4) Modifier B is added to the pulverized phosphate slag using a powder additive quantitative addition device before it is transported to the finished product warehouse after the slag has been ground in a vertical mill and collected by a dust collector. The amount added is 3‰ of the mass of the pulverized phosphate slag. Then it is transported to the finished product warehouse by a bucket elevator to obtain modified phosphate slag powder.

[0078] Performance testing of modified phosphate slag powder:

[0079] According to Appendix A of GB / T "Granulated Electric Furnace Phosphate Slag Powder for Cement and Concrete", the granulated electric furnace phosphate slag powder was tested at a mass ratio of 7:3 between cement and the granulated electric furnace phosphate slag powder in the above-mentioned examples and comparative examples. The cement used was the reference cement that meets the requirements of Appendix A of GB 8076-2008 "Concrete Admixtures". The 7-day activity index and 28-day activity index of each granulated electric furnace phosphate slag powder were tested. The initial setting time was tested according to GBT 1346-2011 "Test Methods for Standard Consistency Water Requirement, Setting Time and Soundness of Cement". The cement used was the reference cement. The results are shown in Table 1.

[0080] Table 1. Performance Test Results of Modified Phosphate Slag Powder

[0081] serial number 7d activity index / % 28d activity index / % Initial setting time / min Example 1 77.9 96.8 271 Example 2 76.5 97.7 276 Example 3 79.3 98.4 265 Comparative Example 1 (Unoptimized particle size) 57.7 72.3 481 Comparative Example 2 (without modifier) 62.2 81.6 376 Comparative Example 3 (Single Modifier A) 69.0 86.1 348 Comparative Example 4 (Single Modifier B) 65.8 87.2 359 Comparative Example 5 (Monodiethanolamine) 76.0 94.3 289 Comparative Example 6 (Monotriethanolamine) 75.6 93.0 296

[0082] As can be seen from Examples 1 to 3 in Table 1, the activity index of the modified granulated electric furnace slag powder of the present invention is stable at 7d / 28d above 76% / 96% respectively, and the initial setting time is ≤280min, which can significantly inhibit the slow setting of granulated electric furnace slag powder and improve its activity.

[0083] As can be seen from the comparison between Example 1 and Comparative Example 1 in Table 1, the modified phosphate slag powder of the present invention has a 7d / 28d activity index increase of 20.2% / 24.5% compared with the unmodified phosphate slag powder of the prior art, and the initial setting time of the slurry is shortened by 210 min, which has significant technical effects.

[0084] A comparison of the test results of Examples 1, 2, 3, and 4 in Table 1 shows that when modifier A is used alone, the 7-day / 28-day activity index of granulated electric furnace phosphate slag powder increases by 6.8% / 4.5%, and when modifier B is used alone, the 7-day / 28-day activity index increases by 3.6% / 5.6%. When both are used in combination, the 7-day / 28-day activity index increase of granulated electric furnace phosphate slag powder should be lower than 10.4% / 10.1%. However, the actual measured increase in Example 1 was 15.7% / 15.2%, significantly higher than the theoretical maximum upper limit. This indicates that modifier A and modifier B in this invention have a significant synergistic effect in increasing the activity index of the modified phosphate slag powder. The inventors believe that this is related to the fact that when modifier A and modifier B are used in combination, they can synergistically increase the potential hydration activity activation degree of the granulated electric furnace phosphate slag.

[0085] As can be seen from the comparison of the test results of Example 1, Comparative Example 5 and Comparative Example 6 in Table 1, under the premise that the proportion of modified chelating agent used is exactly the same, the initial setting time of Comparative Example 5 using diethanolamine alone is 289 min, and the initial setting time of Comparative Example 6 using triethanolamine alone is 296 min. However, when the two are combined into a composite modified chelating agent system, the initial setting time of Example 1 is only 271 min, which is significantly better than the technical effect when they are used alone. It can be seen that the composite modified chelating system composed of diethanolamine and triethanolamine in this invention has a significant synergistic effect in inhibiting the retarding of the added modified phosphorus slag powder. The inventors believe that the reason is related to the fact that when diethanolamine and triethanolamine are used in combination in this invention, they can synergistically improve the dissolution rate of the active component of the system.

Claims

1. A method for inhibiting the retarding and enhancing the activity of granulated electric furnace phosphorus slag powder, characterized in that: The process includes the use of a modifier in the preparation of modified phosphate slag powder; the modifier includes modifier A and modifier B; modifier A comprises the following effective components in the following mass proportions: 28 parts calcium nitrite, 5-15 parts modified chelating agent, and 0.08-0.30 parts calcium hydroxide; the modified chelating agent includes diethanol monoisopropanolamine; modifier B includes industrial sodium silicate powder; specifically, the process includes the following steps: S1. Prepare the modifier; wherein modifier A is prepared as a liquid and modifier B is a solid powder; S2. Before the granulated electric furnace phosphorus slag enters the grinding device, modifier A is sprayed on the surface of the granulated electric furnace phosphorus slag. The amount of modifier A sprayed is 1‰ to 3‰ of the mass of the granulated electric furnace phosphorus slag, so as to obtain pretreated phosphorus slag. S3. Grind the pretreated phosphorus slag using a grinding device to obtain ground phosphorus slag; S4. Add modifier B to the pulverized phosphorus slag and mix evenly. The amount of modifier B added is 1‰ to 3‰ of the mass of the pulverized phosphorus slag, to obtain modified phosphorus slag powder.

2. The method for inhibiting the retarding and enhancing the activity of granulated electric furnace phosphorus slag powder according to claim 1, characterized in that: The improved chelating agent is composed of diethanol monoisopropanolamine and triethanolamine in a mass ratio of 1:2 to 3.

3. The method for inhibiting the retarding and enhancing the activity of granulated electric furnace phosphorus slag powder according to claim 1, characterized in that: In the preparation of the modifier A, the mass ratio of the effective component of modifier A to water is 1:1.2 to 2.

5.

4. The method for inhibiting the retarding and enhancing the activity of granulated electric furnace phosphorus slag powder according to claim 1, characterized in that: The industrial sodium silicate powder has a fineness of <100μm and a modulus of 1 to 3.

5. The method for inhibiting the retarding and enhancing the activity of granulated electric furnace phosphorus slag powder according to claim 1, characterized in that: The method for spraying the modifier A is as follows: atomizing and spraying using an atomizing spraying device.

6. The method for inhibiting the retarding and enhancing the activity of granulated electric furnace phosphorus slag powder according to claim 1, characterized in that: The pulverized phosphorus slag meets the following requirements: particle size <2μm ≤10%, d50 ≤12μm, d90 ≤25μm, and specific surface area of ​​400-500m². 2 / kg.

7. Modified phosphorus slag powder prepared by the method described in any one of claims 1 to 6 for inhibiting the slow coagulation and enhancing the activity of granulated electric furnace phosphorus slag powder.

8. A method for preparing a cement-based material, characterized in that: The raw material formula includes the modified phosphorus slag powder as described in claim 7.

9. A cement-based building material prepared by the method for preparing cement-based materials according to claim 8.