Supersulfurized phosphogypsum slag cement cementing material and preparation method thereof

Abstract

The invention relates to the technical field of solid waste resource utilization, in particular to a persulfide phosphogypsum slag cement cementing material and a preparation method thereof. The persulfide ardealite slag cement cementing material comprises a cementing material and an early strength modifier, the cementing material comprises the following components in parts by weight: 45-50 parts of semi-hydrated phosphogypsum, 40-50 parts of slag powder, 0-4 parts of quick lime and 0-8 parts of cement clinker; the quicklime and the cement clinker are not 0 at the same time; the early strength modifier comprises the following components in parts by weight: 0-0.8 part of an accelerator, 0-0.4 part of a defoaming agent, 0-0.3 part of a water reducing agent and 0-2.5 parts of water glass; the setting accelerator, the defoaming agent, the water reducing agent and the water glass are not 0 at the same time. The oversulfated ardealite slag cement cementing material provided by the invention overcomes the defect of low early strength of common oversulfated ardealite slag cement, the raw materials are easily available and low in cost, and the preparation method is simple and convenient to popularize and produce.

Description

Technical Field

[0001] The present invention relates to the technical field of solid waste resource utilization, and particularly relates to a persulfate phosphogypsum slag cementitious material and a preparation method thereof. Background Art

[0002] At present, the semi-hydrate-wet process and the dihydrate-wet process are considered to be the main methods for phosphoric acid production. As a by-product of the phosphochemical industry, semi-hydrate phosphogypsum is mainly treated by surface storage, which inevitably brings a series of problems such as occupying land resources, increasing management costs, and polluting the ecological system. A small amount of impurities such as phosphorus, fluorine, organic matter, and acid-insoluble substances remain in the semi-hydrate phosphogypsum, which greatly inhibits the hydration and cementitious activity of the semi-hydrate phosphogypsum and seriously restricts the application of the semi-hydrate phosphogypsum in the field of building cementitious materials.

[0003] Persulfate cement is a cementitious material prepared from raw materials with a phosphogypsum content of not less than 45%, and compounded with slag and alkaline activators. Persulfate cement has significant environmental friendliness and good physical and chemical properties. Its main characteristics include low heat of hydration, excellent corrosion resistance, and high late strength. However, studies have found that the strength of persulfate cement in the early 3 days is lower than that of slag Portland cement and ordinary Portland cement, but its strength increases rapidly after 7 days of age and reaches the same strength as ordinary Portland cement after 28 days. Therefore, a major defect of persulfate cement is its long setting and hardening time and low early strength. The improvement of early strength is crucial for the application of building materials. First of all, the increase in early strength can shorten the construction period and speed up the project progress. Secondly, the improvement of early strength helps to resist the influence of external environmental factors during the construction process, especially in areas with large changes in humidity and temperature. In addition, increasing the early strength can also reduce the cracking risk of concrete and improve the long-term durability of the structure. Therefore, it is of great significance to improve the early strength of persulfate cement.

[0004] The literature "Research on the Influence of Pretreatment Methods on the Performance of Persulfate Phosphogypsum Slag Cement Slurry" starts from the physical modification of raw materials and explores the influence of different pretreatment methods and times on the performance of persulfate phosphogypsum slag cement (Method 1: drying the original phosphogypsum at 60°C, simply crushing it, and then passing it through a 0.08 mm standard sieve; Method 2: drying the original phosphogypsum at 60°C, then grinding it in a ball mill (WZM-10L, double tank) for a certain time and passing it through a 0.08 mm standard sieve; Method 3: drying the original phosphogypsum at 60°C, then adding blast furnace slag powder and cement to the ball mill according to the proportion of making neat mortar specimens, grinding for different times and passing it through a 0.08 mm standard sieve; Method 4: wet grinding the phosphogypsum for a certain time and aging it for 24 h to obtain a modified phosphogypsum slurry). Although these methods improve the early strength of persulfate phosphogypsum slag cement to a certain extent, the improvement amplitude is not obvious enough.

[0005] In the literature "Research on the Influence of Phosphogypsum Quality on the Performance of Over-Sulfur Phosphogypsum Slag Cement Paste", it is found that harmful impurities such as soluble phosphorus, eutectic phosphorus and soluble fluorine in phosphogypsum will reduce the early strength of over-sulfur phosphogypsum slag cement. Phosphogypsum pretreated with an appropriate amount of steel slag powder can shorten the setting time of the cement paste and improve its early strength. However, the compressive strength after 3 days of treatment is only 3 - 5 MPa, and the improvement of early strength is not obvious enough.

[0006] In the literature "Influence of Admixtures on the Early Performance of Over-Sulfur Phosphogypsum Slag Cement", by first pretreating the raw material phosphogypsum and then using silica fume and metakaolin to replace slag, although it can significantly improve the early strength of over-sulfur phosphogypsum slag cement, this treatment method is energy-consuming and costly.

[0007] In the literature "Influence of Curing Conditions on the Performance of Over-Sulfur Phosphogypsum Slag Cement Mortar", it is found that the steam curing method can promote the formation of hydration product ettringite and improve the early strength of over-sulfur phosphogypsum slag cement. However, this method is easily affected by external conditions and is not convenient for popularization and utilization.

[0008] Patent application document CN114835423A discloses a preparation process of an early strength agent: mixing Ca(OH)₂ solution and Al₂(SO₄)₃ solution evenly, adding boric acid accounting for 1.5% of the total mass of Ca(OH)₂ and (Al₂(SO₄)₃·18H₂O), and adding a NaOH solution with a concentration of 0.1 mol / L to adjust the pH value. After magnetic stirring at 40 °C for 24 h, the synthesized emulsion is filtered, washed, dried and ground to obtain an early strength agent for over-phosphogypsum slag cement. This early strength agent can significantly improve the early strength of over-phosphogypsum slag cement, but the preparation process is relatively cumbersome and complex. Summary of the Invention

[0009] In view of this, the technical problem to be solved by the present invention is to provide a cementitious material for over-sulfur phosphogypsum slag cement and its preparation method, which makes up for the shortcoming of low early strength of general over-sulfur phosphogypsum slag cement, has easily available raw materials and a simple preparation method.

[0010] The present invention provides a cementitious material for over-sulfur phosphogypsum slag cement, comprising a cementitious material and an early strength modifier;

[0011] The cementitious material includes: 45 - 50 parts by weight of hemihydrate phosphogypsum, 40 - 50 parts by weight of slag powder, 0 - 4 parts by weight of quicklime, and 0 - 8 parts by weight of cement clinker; the quicklime and the cement clinker are not both 0;

[0012] The early strength modifier includes 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, 0-0.3 parts by weight of a water reducing agent, and 0-2.5 parts by weight of sodium silicate; the setting accelerator, the antifoaming agent, the water reducing agent, and the sodium silicate are not all 0 at the same time.

[0013] Preferably, the components of the cementitious material are: 45-50 parts by weight of hemihydrate phosphogypsum, 40-50 parts by weight of slag powder, 0-4 parts by weight of quicklime, and 0-8 parts by weight of cement clinker; and both the quicklime and the cement clinker are not 0.

[0014] Preferably, the components of the early strength modifier are: 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, and 0-0.3 parts by weight of a water reducing agent; and the setting accelerator, the antifoaming agent, and the water reducing agent are not all 0 at the same time.

[0015] Preferably, the components of the early strength modifier are: 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, 0-0.3 parts by weight of a water reducing agent, and 0-2.5 parts by weight of sodium silicate; the setting accelerator, the antifoaming agent, the water reducing agent, and the sodium silicate are not all 0 at the same time.

[0016] Preferably, in the hemihydrate phosphogypsum, by mass content, the crystal water content is 6%-8%, and the free water content is 19%-24%.

[0017] Preferably, the grade of the slag powder is S95, and the specific surface area of the slag powder is ≥600 m 2 / kg.

[0018] Preferably, the quicklime belongs to the second-grade calcareous ash;

[0019] In the quicklime, the mass content of calcium oxide is ≥80%.

[0020] Preferably, the cement clinker is ground from Portland cement clinker, and the specific surface area is ≥340 m 2 / kg.

[0021] Preferably, the water reducing agent is a polycarboxylate water reducing agent;

[0022] The modulus of the sodium silicate is ≥2.7.

[0023] The present invention also provides a preparation method of the above-mentioned over-sulfur phosphogypsum slag cementitious material, including the following steps:

[0024] Mix the cementitious material and the early strength modifier evenly to obtain the over-sulfur phosphogypsum slag cementitious material.

[0025] The present invention provides a supersulfated phosphogypsum slag cementitious material, which comprises a cementitious material and an early strength modifier; the cementitious material includes: 45-50 parts by weight of hemihydrate phosphogypsum, 40-50 parts by weight of slag powder, 0-4 parts by weight of quicklime, and 0-8 parts by weight of cement clinker; the quicklime and the cement clinker are not both 0 at the same time; the early strength modifier includes 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, 0-0.3 parts by weight of a water reducing agent, and 0-2.5 parts by weight of sodium silicate; the setting accelerator, the antifoaming agent, the water reducing agent and the sodium silicate are not all 0 at the same time. The present invention directly uses the industrial by-product hemihydrate phosphogypsum to prepare an early strength supersulfated phosphogypsum slag cementitious material, improving the comprehensive utilization rate of industrial waste. The hemihydrate phosphogypsum can cooperate well with other components, and the prepared supersulfated phosphogypsum slag cementitious material makes up for the disadvantage of low early strength of general supersulfated phosphogypsum slag cement. The raw materials are easily available and the cost is low, and the preparation method is simple, which is convenient for popularization and production. Detailed implementation mode

[0026] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0027] The present invention provides a supersulfated phosphogypsum slag cementitious material, which comprises a cementitious material and an early strength modifier;

[0028] The cementitious material includes: 45-50 parts by weight of hemihydrate phosphogypsum, 40-50 parts by weight of slag powder, 0-4 parts by weight of quicklime, and 0-8 parts by weight of cement clinker; the quicklime and the cement clinker are not both 0 at the same time;

[0029] The early strength modifier includes 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, 0-0.3 parts by weight of a water reducing agent, and 0-2.5 parts by weight of sodium silicate; the setting accelerator, the antifoaming agent, the water reducing agent and the sodium silicate are not all 0 at the same time.

[0030] In some embodiments of the present invention, the components of the cementitious material are: 45-50 parts by weight of hemihydrate phosphogypsum, 40-50 parts by weight of slag powder, 0-4 parts by weight of quicklime, and 0-8 parts by weight of cement clinker; and both the quicklime and the cement clinker are not 0.

[0031] Specifically, the components of the cementitious material are: 47 parts by weight of hemihydrate phosphogypsum, 49 parts by weight of slag powder, 2.6 parts by weight of quicklime, and 1.4 parts by weight of cement clinker.

[0032] Or the components of the cementitious material are: 48 parts by weight of hemihydrate phosphogypsum, 49 parts by weight of slag powder, 2.6 parts by weight of quicklime, and 0.4 parts by weight of cement clinker.

[0033] Or the components of the cementitious material are: 47 parts by weight of hemihydrate phosphogypsum, 46 parts by weight of slag powder, 1 part by weight of quicklime, and 6 parts by weight of cement clinker.

[0034] Or the components of the cementitious material are: 45 parts by weight of hemihydrate phosphogypsum, 50 parts by weight of slag powder, 1 part by weight of quicklime, and 4 parts by weight of cement clinker.

[0035] In some embodiments of the present invention, the components of the early strength modifier are: 0 - 0.8 parts by weight of a setting accelerator, 0 - 0.4 parts by weight of an antifoaming agent, 0 - 0.3 parts by weight of a water reducing agent; and the setting accelerator, antifoaming agent, and water reducing agent are not all 0.

[0036] Specifically, the components of the early strength modifier are: 0.8 parts by weight of a setting accelerator, 0.1 parts by weight of an antifoaming agent, and 0.3 parts by weight of a water reducing agent.

[0037] In some embodiments of the present invention, the components of the early strength modifier are: 0 - 0.8 parts by weight of a setting accelerator, 0 - 0.4 parts by weight of an antifoaming agent, 0 - 0.3 parts by weight of a water reducing agent, 0 - 2.5 parts by weight of sodium silicate; the setting accelerator, antifoaming agent, water reducing agent, and sodium silicate are not all 0.

[0038] Specifically, the components of the early strength modifier are: 0.8 parts by weight of a setting accelerator, 0.25 parts by weight of an antifoaming agent, 0.25 parts by weight of a water reducing agent, and 0.2 parts by weight of sodium silicate.

[0039] Or the components of the early strength modifier are: 0.6 parts by weight of a setting accelerator, 0.2 parts by weight of an antifoaming agent, 0.1 parts by weight of a water reducing agent, and 1.6 parts by weight of sodium silicate.

[0040] Or the components of the early strength modifier are: 0.8 parts by weight of a setting accelerator, 0.2 parts by weight of an antifoaming agent, 0.1 parts by weight of a water reducing agent, and 2.4 parts by weight of sodium silicate.

[0041] In some embodiments of the present invention, the hemihydrate phosphogypsum is an industrial by - product of wet - process phosphoric acid in the phosphochemical industry. In the hemihydrate phosphogypsum, by mass content, the content of hemihydrate calcium sulfate is above 90%, the crystal water content is 6% - 8%, and the free water content is 19% - 24%.

[0042] In some embodiments of the present invention, the slag powder is of grade S95, and the specific surface area of the slag powder ≥ 600m 2 / kg.

[0043] In some embodiments of the present invention, the quicklime belongs to secondary calcareous ash; in the quicklime, the mass content of calcium oxide is ≥ 80%.

[0044] In some embodiments of the present invention, the cement clinker is ground from portland cement clinker, and the specific surface area is ≥ 340 m 2 / kg.

[0045] In some embodiments of the present invention, the water reducing agent is a polycarboxylate water reducing agent.

[0046] In some embodiments of the present invention, the modulus of the sodium silicate is ≥ 2.7, such as 2.7 - 3.0.

[0047] The accelerating agent, defoaming agent, water reducing agent, and sodium silicate are all commercially available.

[0048] The superphosphate gypsum slag cementitious material provided by the present invention is obtained by mixing a cementitious material and an early strength modifier.

[0049] The present invention also provides a preparation method of the above-mentioned superphosphate gypsum slag cementitious material, comprising the following steps:

[0050] Mix the cementitious material and the early strength modifier to obtain the superphosphate gypsum slag cementitious material.

[0051] The superphosphate gypsum slag cementitious material is an early strength type superphosphate gypsum slag cement, and the preparation method is simple, and the raw materials are easy to obtain, which is suitable for application in the field of building cementitious materials.

[0052] The present invention has no special restrictions on the sources of the raw materials used above, and they can be commercially available.

[0053] In order to further illustrate the present invention, the following examples are used to describe in detail a superphosphate gypsum slag cementitious material and its preparation method provided by the present invention, but it should not be construed as a limitation to the protection scope of the present invention.

[0054] In the examples, in the hemihydrate phosphogypsum, by mass content, the content of hemihydrate calcium sulfate is above 90%, the crystal water content is 6% - 8%, and the free water content is 19% - 24%.

[0055] The grade of the slag powder is S95, and the specific surface area of the slag powder is ≥ 600 m 2 / kg.

[0056] The quicklime belongs to secondary calcareous ash; in the quicklime, the mass content of calcium oxide is ≥ 80%.

[0057] The cement clinker is ground from portland cement clinker, and the specific surface area is ≥ 340 m 2 / kg.

[0058] The accelerating agent, defoaming agent, water reducing agent, and water glass are all commercially available.

[0059] The water reducing agent is a polycarboxylate water reducing agent.

[0060] The modulus of the water glass is 2.7 - 3.0.

[0061] Example 1

[0062] The components of the supersulfated phosphorite slag cementitious material are a cementitious material and an early strength modifier;

[0063] The components of the cementitious material are: 47 parts by weight of hemihydrate phosphorite gypsum, 49 parts by weight of slag powder, 2.6 parts by weight of quicklime, and 1.4 parts by weight of cement clinker;

[0064] The components of the early strength modifier are: 0.8 parts by weight of accelerating agent, 0.25 parts by weight of defoaming agent, 0.25 parts by weight of water reducing agent, and 0.2 parts by weight of water glass.

[0065] Preparation of the supersulfated phosphorite slag cementitious material:

[0066] Mix the cementitious material and the early strength modifier evenly to obtain the supersulfated phosphorite slag cementitious material.

[0067] Example 2

[0068] The components of the supersulfated phosphorite slag cementitious material are a cementitious material and an early strength modifier;

[0069] The components of the cementitious material are: 48 parts by weight of hemihydrate phosphorite gypsum, 49 parts by weight of slag powder, 2.6 parts by weight of quicklime, and 0.4 parts by weight of cement clinker;

[0070] The components of the early strength modifier are: 0.8 parts by weight of accelerating agent, 0.1 parts by weight of defoaming agent, and 0.3 parts by weight of water reducing agent.

[0071] Preparation of the supersulfated phosphorite slag cementitious material:

[0072] Mix the cementitious material and the early strength modifier evenly to obtain the supersulfated phosphorite slag cementitious material.

[0073] Example 3

[0074] The components of the supersulfated phosphorite slag cementitious material are a cementitious material and an early strength modifier;

[0075] The components of the cementitious material are: 47 parts by weight of hemihydrate phosphorite gypsum, 46 parts by weight of slag powder, 1 part by weight of quicklime, and 6 parts by weight of cement clinker;

[0076] The components of the early-strength modifier are as follows: 0.6 parts by weight of a setting accelerator, 0.2 parts by weight of an antifoaming agent, 0.1 parts by weight of a water-reducing agent, and 1.6 parts by weight of sodium silicate.

[0077] Preparation of the supersulfated phosphorgypsum slag cementitious material:

[0078] Mix the cementitious material and the early-strength modifier evenly to obtain the supersulfated phosphorgypsum slag cementitious material.

[0079] Example 4

[0080] The components of the supersulfated phosphorgypsum slag cementitious material are a cementitious material and an early-strength modifier;

[0081] The components of the cementitious material are as follows: 45 parts by weight of hemihydrate phosphorgypsum, 50 parts by weight of slag powder, 1 part by weight of quicklime, and 4 parts by weight of cement clinker;

[0082] The components of the early-strength modifier are as follows: 0.8 parts by weight of a setting accelerator, 0.2 parts by weight of an antifoaming agent, 0.1 parts by weight of a water-reducing agent, and 2.4 parts by weight of sodium silicate.

[0083] Preparation of the supersulfated phosphorgypsum slag cementitious material:

[0084] Mix the cementitious material and the early-strength modifier evenly to obtain the supersulfated phosphorgypsum slag cementitious material.

[0085] Example 5

[0086] The difference from Example 4 is that:

[0087] The components of the cementitious material are as follows: 45 parts by weight of hemihydrate phosphorgypsum, 50 parts by weight of slag powder, and 5 parts by weight of quicklime.

[0088] The remaining components, dosages, and steps are the same as those in Example 4.

[0089] Example 6

[0090] The difference from Example 4 is that:

[0091] The components of the cementitious material are as follows: 45 parts by weight of hemihydrate phosphorgypsum, 50 parts by weight of slag powder, and 5 parts by weight of cement clinker.

[0092] The remaining components, dosages, and steps are the same as those in Example 4.

[0093] Example 7

[0094] The difference from Example 4 is that:

[0095] The components of the early-strength modifier are as follows: 0.8 parts by weight of a setting accelerator, 0.2 parts by weight of an antifoaming agent, and 2.5 parts by weight of sodium silicate.

[0096] The remaining components, dosages, and steps are the same as those in Example 4.

[0097] Example 8

[0098] The difference from Example 4 is as follows:

[0099] The components of the early strength modifier are: 0.8 parts by weight of a setting accelerator, 0.3 parts by weight of a water reducing agent, and 2.4 parts by weight of sodium silicate.

[0100] The remaining components, dosages, and steps are the same as those in Example 4.

[0101] Comparative Example 1

[0102] The difference from Example 1 is as follows:

[0103] Replace the super-sulfated phosphorgypsum slag cementitious material in Example 1 with super-sulfated phosphorgypsum slag cement.

[0104] As described in the reference "Effect of Water-Cement Ratio on the Strength of Super-Sulfated Phosphorgypsum Slag Cement", the components of super-sulfated phosphorgypsum slag cement are: 45% by mass of phosphogypsum, 47% by mass of slag powder, and 8% by mass of cement clinker. The phosphogypsum is taken from Hubei Mailin Phosphochemical Co., Ltd., with a water content of 16% (by mass), and the basic component is dihydrate phosphogypsum. The slag powder is of S95 grade and is taken from Wuhan Wuxin New Building Materials Co., Ltd. The cement clinker is taken from Huaxin Cement Co., Ltd.

[0105] Comparative Example 2

[0106] Replace the super-sulfated phosphorgypsum slag cementitious material in Example 1 with slag Portland cement 42.5, taken from Anhui Conch Cement Co., Ltd.

[0107] Comparative Example 3

[0108] Replace the super-sulfated phosphorgypsum slag cementitious material in Example 1 with ordinary Portland cement 42.5, taken from Anhui Conch Cement Co., Ltd.

[0109] Study the compressive strength and flexural strength of the composite cementitious materials (specifically, the super-sulfated phosphorgypsum slag cementitious materials of Examples 1 to 8 and the materials of Comparative Examples 1 to 3) at 3d, 7d, and 28d. The results are shown in Table 2.

[0110] Refer to the method in the standard GB / T 17671-1999 "Methods of Testing Cement - Determination of Strength of Cement Mortar (ISO Method)" to make cement mortar test molds; use a fully automatic pressure testing machine to measure the compressive strength and flexural strength of the specimens, referring to the standards of GB 1344-1999 "Slag Portland Cement, Fly Ash Portland Cement and Pozzolan Portland Cement" and GB 175-2023 "General Portland Cement".

[0111] Table 2 Compressive strength and flexural strength of composite cementitious materials at 3d, 7d, and 28d

[0112]

[0113] The experimental results show that the strength of general supersulfated phosphorgypsum slag cement at the early stage of 3d is significantly lower than that of slag Portland cement and ordinary Portland cement. However, the cementitious material of supersulfated phosphorgypsum slag cement provided by the present invention makes up for the disadvantage of low early strength of general supersulfated phosphorgypsum slag cement, and the later strength of the early-strength supersulfated phosphorgypsum slag cement is basically consistent with that of slag Portland cement and ordinary Portland cement, and even better.

[0114] The description of the above embodiments is only used to help understand the method and its core idea of the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A persulfurated phosphogypsum slag cementitious material, comprising a cementitious material and an early strength modifier; The cementitious material includes: 45-50 parts by weight of hemihydrate phosphogypsum, 40-50 parts by weight of slag powder, 0-4 parts by weight of quicklime, 0-8 parts by weight of cement clinker; The quicklime and the cement clinker are not both 0 at the same time; The early strength modifier includes 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, 0-0.3 parts by weight of a water reducing agent, and 0-2.5 parts by weight of sodium silicate; the setting accelerator, the antifoaming agent, the water reducing agent and the sodium silicate are not all 0 at the same time.

2. The peroxysulfate gypsum slag cementitious material according to claim 1, wherein, The components of the cementitious material are: 45-50 parts by weight of hemihydrate phosphogypsum, 40-50 parts by weight of slag powder, 0-4 parts by weight of quicklime, 0-8 parts by weight of cement clinker; and both the quicklime and the cement clinker are not 0.

3. The superphosphorus gypsum slag cementitious material according to claim 1, characterized in that, The components of the early strength modifier are: 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, 0-0.3 parts by weight of a water reducing agent; and the setting accelerator, the antifoaming agent and the water reducing agent are not all 0.

4. The superphosphorus gypsum slag cementitious material according to claim 1, wherein The components of the early strength modifier are: 0-0.8 parts by weight of a setting accelerator, 0-0.4 parts by weight of an antifoaming agent, 0-0.3 parts by weight of a water reducing agent, 0-2.5 parts by weight of sodium silicate; the setting accelerator, the antifoaming agent, the water reducing agent and the sodium silicate are not all 0.

5. The over-sulfurized phosphogypsum slag cementitious material according to claim 1, wherein, In the hemihydrate phosphogypsum, by mass content, the content of hemihydrate calcium sulfate is above 90%, the crystal water content is 6%-8%, and the free water content is 19%-24%.

6. The super-sulfated phosphorus gypsum slag cementitious material according to claim 1, characterized in that, The grade of the slag powder is S95, and the specific surface area of the slag powder ≥ 600 m 2 / kg.

7. The peroxyphosphogypsum slag cementitious material according to claim 1, characterized in that, The quicklime belongs to secondary calcareous ash; In the quicklime, the mass content of calcium oxide ≥ 80%; 8. The superphosphate gypsum slag cementitious material according to claim 1, characterized in that, The cement clinker is ground from Portland cement clinker, with a specific surface area of ≥ 340 m 2 / kg.

9. The superphosphorus gypsum slag cementitious material according to claim 1, characterized in that, The water reducing agent is a polycarboxylate water reducing agent; The sodium silicate modulus ≥ 2.7; 10. A preparation method of the persulfurated phosphogypsum slag cementitious material according to any one of claims 1-9, comprising the following steps: Mix the cementitious material and the early strength modifier evenly to obtain the persulfurated phosphogypsum slag cementitious material.

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