Flocculation dewatered cement slag strength deterioration resistant additive, synchronous grouting material and preparation method thereof

Abstract

The invention belongs to the technical field of inorganic gelling agent additives, and particularly relates to a strength deterioration resistant additive for flocculation and dehydration of cement residues, a synchronous grouting material and a preparation method of the synchronous grouting material, and the synchronous grouting material comprises the following components in parts by mass: 0.1-2 parts of a strong electron acceptor; 0.1-1 part of a strong proton acceptor; 0.1-2 parts of a high-charge metal ion compound; 90-180 parts of industrial solid waste; the strong electron acceptor is persulfate; the strong proton acceptor is cesium hydroxide or / and rubidium hydroxide; the high-charge metal ion compound is selected from at least one of ferric nitrate, ferric sulfate, aluminum nitrate or aluminum sulfate; the industrial solid waste is common industrial solid waste and superfine industrial solid waste. The synchronous grouting material has the advantages of being high in stability, excellent in mechanical property, low in cost, environmentally friendly, low in carbon and the like, and high-added-value utilization of dewatered cement slag type waste is achieved easily.

Description

Technical Field

[0001] This invention belongs to the field of inorganic cementitious additive technology, specifically relating to an additive for resisting the deterioration of the strength of flocculated dewatering slag, a synchronous grouting material, and its preparation method. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] The construction of underground projects such as subways and sand washing operations generate large amounts of wastewater containing suspended solids. Direct discharge of this wastewater would pollute the soil and water bodies. Therefore, flocculants are generally used in conjunction with filter presses to quickly separate the mud and water, allowing for water resource recycling. However, this process also produces flocculated dewatering slag containing a large amount of flocculant. The large accumulation of dewatering slag can cause environmental problems such as water pollution, river blockage, and soil contamination, endangering human health and affecting the living environment. Therefore, the effective utilization of dewatering slag is urgently needed.

[0004] The particles of flocculated dewatering slag are extremely fine, resulting in high moisture content and high viscosity. Furthermore, the slag contains a large amount of flocculant, which can easily prevent the grouting material from solidifying when used in conjunction with cement to prepare synchronous grouting materials. Therefore, the common treatment method for flocculated dewatering slag is solidification and stockpiling / backfilling, but this method consumes a large amount of valuable land resources. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an additive for resisting strength degradation of flocculated dewatering slag, a synchronous grouting material, and a method for preparing the same. This synchronous grouting material possesses advantages such as high stability, excellent mechanical properties, low cost, and green and low-carbon characteristics, which is beneficial for achieving high-value-added utilization of dewatering slag waste.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, the present invention provides an additive for resisting the deterioration of the strength of flocculated dewatering slag, comprising the following components by weight: 0.1-2 parts of a strong electron acceptor; 0.1-1 parts of a strong proton acceptor; 0.1-2 parts of a high-charge metal ion compound; and 90-180 parts of industrial solid waste. The strong electron acceptor is a persulfate; The strong proton acceptor is cesium hydroxide and / or rubidium hydroxide; The high-charge metal ion compound is selected from at least one of ferric nitrate, ferric sulfate, aluminum nitrate, or aluminum sulfate; The industrial solid waste comprises general industrial solid waste (granulated blast furnace slag powder, phosphorus slag powder, red mud, steel slag powder) and ultrafine industrial solid waste (silica fume, ultrafine granulated blast furnace slag powder, ultrafine fly ash), consisting of one or more of the general industrial solid waste granulated blast furnace slag powder and phosphorus slag powder, one or more of the red mud and steel slag powder, and one or more of the ultrafine industrial solid waste silica fume, ultrafine granulated blast furnace slag powder, and ultrafine fly ash.

[0007] In a second aspect, the present invention provides a synchronous grouting material, comprising the following components by weight: 1000 parts of flocculated dewatering slag, 100-200 parts of cement, 90-185 parts of the strength deterioration resistance additive mentioned in the first aspect, and 440-600 parts of water.

[0008] Thirdly, the present invention provides a method for preparing the synchronous grouting material, comprising the following steps: Step 1: Weigh the raw materials, including dewatered slag, cement, strength-degrading additives, and water; Step 2: Thoroughly mix the dewatered slag, cement, strength deterioration additive, and water for at least 3 minutes. Step 3: Place the mixed slurry in a storage container for later use, and continue stirring to prevent segregation during settling. Step four: Use professional pumping equipment and pipelines to pump the slurry to the designated location.

[0009] The beneficial effects achieved by one or more embodiments of the present invention described above are as follows: (1) The strength degradation resistance additive of the present invention is composed of a strong electron acceptor, a strong proton acceptor, a high-charge metal ion compound, and industrial solid waste. The additive breaks down the flocculant macromolecular chain by disrupting the flocculated network structure and allows the cement hydration reaction to proceed normally through competitive adsorption via ion exchange. After adding the additive to the synchronous grouting material, the mechanical properties of the synchronous grouting material can be significantly improved, and the long-term performance of the aggregate can be improved.

[0010] (2) The strength degradation resistance additive of the present invention can be added as an admixture during the production of synchronous slurry from dewatered slag, or it can be used as a cement admixture in other scenarios containing flocculants, or it can be used in combination with other admixtures. The raw materials are conventional chemical products and industrial solid waste, which are readily available and inexpensive.

[0011] (3) The present invention provides a method for preparing shield tunneling synchronous grout from dewatered slag. On the one hand, it enables any flocculated dewatered slag to be used to prepare shield tunneling synchronous grout or to expand its application to other scenarios. On the other hand, it significantly reduces the amount of cement used. This saves costs and allows for the large-scale disposal of dewatered slag, resulting in the preparation of green, low-carbon, and low-cost synchronous grouting materials. Detailed Implementation

[0012] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0013] In a first aspect, the present invention provides an additive for resisting the deterioration of the strength of flocculated dewatering slag, comprising the following components by weight: 0.1-2 parts of a strong electron acceptor; 0.1-1 parts of a strong proton acceptor; 0.1-2 parts of a high-charge metal ion compound; and 90-180 parts of industrial solid waste. The strong electron acceptor is a persulfate; The strong proton acceptor is cesium hydroxide and / or rubidium hydroxide; The high-charge metal ion compound is selected from at least one of ferric nitrate, ferric sulfate, aluminum nitrate, or aluminum sulfate.

[0014] The industrial solid waste comprises general industrial solid waste (granulated blast furnace slag powder, phosphorus slag powder, red mud, steel slag powder) and ultrafine industrial solid waste (silica fume, ultrafine granulated blast furnace slag powder, ultrafine fly ash), consisting of one or more of the general industrial solid waste granulated blast furnace slag powder and phosphorus slag powder, one or more of the red mud and steel slag powder, and one or more of the ultrafine industrial solid waste silica fume, ultrafine granulated blast furnace slag powder, and ultrafine fly ash.

[0015] Flocculants form a large molecular chain network structure in dewatered cement slag. When a large amount of dewatered cement slag containing flocculants is mixed with cement to prepare synchronous grouting material, the large molecular chain network structure of the flocculant will encapsulate cement particles through electrostatic adsorption, hindering the contact between cement and water. This prevents the cement hydration reaction from proceeding normally, ultimately causing the synchronous grouting material to be difficult to solidify. The electrostatic adsorption between flocculant and cement particles is mainly due to the Al2O3 surface layer on the cement particles. 3+ Ca 2+ Isocations are generated.

[0016] Within minutes of the hydration reaction, the strong electron acceptor is readily soluble in water and can react rapidly with the flocculant molecules. Utilizing its extremely strong electron acceptor ability, it can destroy the macromolecular chain structure of the flocculant within minutes of contact with water, causing the flocculation network to disintegrate and releasing the encapsulated cement particles.

[0017] Within minutes of the hydration reaction, the strong proton acceptor is highly soluble in water and can quickly adjust the pH of the system. Through its strong proton acceptor ability, it works synergistically with the strong electron acceptor to accelerate the destruction of the flocculation structure and further improve the cement hydration environment.

[0018] Within minutes of the hydration reaction, highly charged metal ion compounds are competitively adsorbed through ion exchange, releasing cement particles encapsulated by the flocculant. Metal cations providing three or more positive charges (such as Fe) are also involved.3+ Al 3+ ), with Al on the surface of cement particles 3+ Ca 2+ Competing for the adsorption sites of flocculants allows cement particles to be released and participate in the hydration reaction.

[0019] During the hydration reaction, which lasts from several tens of minutes to a long period, industrial solid waste slowly releases Al from the alkaline solution. 3+ Fe 3+ Ca 2+ High-valence metal ions replenish the cations required for ion exchange and participate in subsequent hydration reactions, thereby improving the mechanical properties and durability of the stones.

[0020] If the additive does not contain high-charge metal ion compounds, the adsorption sites of the flocculant cannot be effectively occupied, and the cement particles remain coated, resulting in insufficient contact between the cement and water, and the hydration reaction cannot occur completely; if the metal ion is in a low valence state, such as Zn... 2+ Na + Its electrostatic attraction is weaker than that of 3+ ions, resulting in insufficient competitive adsorption capacity and inability to completely release cement particles, thus significantly reducing the rate and extent of hydration reaction.

[0021] In addition, industrial solid waste is divided into general industrial solid waste and ultrafine industrial solid waste. Both can be continuously hydrated for a long time, filling the large number of pores caused by the high water-cement ratio of dewatering slag. Furthermore, the particle size of ultrafine industrial solid waste is smaller than that of cement, dewatering slag, and other components, which can also fill the pores and increase the density of the stone body.

[0022] In some embodiments, the flocculation dewatering slag strength deterioration resistance additive, by weight, comprises the following components: 0.1-1 part of strong electron acceptor; 0.1-1 part of strong proton acceptor; 0.1-1 part of high-charge metal ion compound; and 100-180 parts of industrial solid waste.

[0023] Preferably, the industrial solid waste is composed of general industrial solid waste and ultrafine industrial solid waste. The general industrial solid waste is selected from at least one of granulated blast furnace slag powder and phosphorus slag powder; and at least one of red mud and steel slag powder. The ultrafine industrial solid waste is selected from at least one of silica fume, ultrafine granulated blast furnace slag powder or ultrafine fly ash.

[0024] Further preferred, the specific surface area of ​​granulated blast furnace slag powder is 500-600 m². 2 / kg; The specific surface area of ​​phosphorus slag powder is 500-600 m². 2 / kg; The specific surface area of ​​red mud is 850-950 m². 2 / kg; The specific surface area of ​​steel slag powder is 500-600 m².2 / kg; The specific surface area of ​​silica fume is 18,000-22,000 m². 2 / kg; Ultrafine blast furnace slag powder has a specific surface area of ​​750-850 m². 2 / kg; Ultrafine fly ash has a specific surface area of ​​850-950 m². 2 / kg.

[0025] More preferably, the industrial solid waste is a mixture of granulated blast furnace slag powder, steel slag powder and ultrafine fly ash, with a mass ratio of 100-130:10-30:10-30.

[0026] More preferably, the industrial solid waste is a mixture of phosphorus slag powder, red mud and ultrafine granulated blast furnace slag powder, and the mass ratio of phosphorus slag powder, red mud and ultrafine granulated blast furnace slag powder is 100-130:10-30:10-30.

[0027] More preferably, the industrial solid waste is a mixture of granulated blast furnace slag powder, red mud, and silica fume, with a mass ratio of granulated blast furnace slag powder, red mud, and silica fume of 100-130:10-30:10-30.

[0028] Granulated blast furnace slag powder and phosphorus slag powder contain a large amount of calcium aluminosilicate glass. Under alkaline conditions, they can undergo secondary hydration reactions with cement hydration products (such as Ca(OH)2) to generate CSH gel and ettringite, which enhance the strength and durability of the aggregate. They dissolve under alkaline conditions, releasing Al. 3+ Ca 2+ Metal cations, such as metal cations, replenish the cations required for ion exchange and promote the continuous hydration reaction of cement particles.

[0029] Red mud and steel slag powder are rich in Al 3+ Fe 3+ High-valence metal cations can complex or electrostatically neutralize with negatively charged flocculant molecular chains, altering the conformation and adsorption behavior of the flocculant, causing partial deactivation, disrupting the electrostatic balance between cement particles and flocculant, and destroying the flocculation network structure formed by the bridging effect of the flocculant; at the same time, red mud has high fineness, which can fill the pores of the system and improve the density of the synchronous grouting material.

[0030] Silica fume, with its extremely high specific surface area and highly reactive amorphous SiO2, can efficiently react with Ca(OH)2, a cement hydration product, to form CSH gel, thereby refining the pore structure and significantly improving the early strength of the aggregate. Simultaneously, its ultrafine particle characteristics optimize the particle size distribution of the system, leveraging the micro-aggregate filling effect. This reduces bleeding while improving the workability and stability of the mixture, further enhancing the mechanical properties of the aggregate.

[0031] Ultrafine blast furnace slag powder possesses a high specific surface area and a highly disordered calcium aluminosilicate glassy structure. Under alkaline conditions, it can rapidly undergo a secondary hydration reaction, efficiently consuming Ca(OH)2 in the system and generating more CSH gel and hydrated calcium aluminate, thereby significantly refining the pore structure and improving the long-term strength and chemical stability of the aggregate. Simultaneously, its micron- and submicron-sized particles effectively optimize the particle size distribution of the cementitious system, exerting a dense packing effect. This improves the workability and flowability of the mixture while reducing bleeding, and further enhances the density and mechanical properties of the matrix through the filling effect of micro-aggregates.

[0032] Ultrafine fly ash features smaller particle size and higher specific surface area. Its main component is amorphous silica-alumina material in the form of spherical glass microspheres. In an alkaline environment, it can more fully exert its pozzolanic activity, continuously consuming Ca(OH)2 to generate CSH gel, thereby optimizing the pore structure and helping to improve the later strength and durability of the aggregate. At the same time, its unique spherical particle morphology can exert a ball-bearing lubrication effect, significantly improving the fluidity of freshly mixed slurry and reducing water demand. It also optimizes particle size distribution and improves the later strength and density of the matrix through the filling effect of micro-aggregates.

[0033] Different industrial solid waste components exert a synergistic enhancement effect through multiple mechanisms: amorphous silica-alumina or highly active SiO2 in components with pozzolanic activity continuously consume Ca(OH)2 under alkaline conditions, generating C S Products such as H-gel and ettringite significantly enhance strength and durability; components rich in high-valence metal cations (such as red mud and steel slag powder) neutralize flocculants through ion exchange and competitive adsorption, regulating slurry rheology and dispersion stability; ultrafine particle components exert micro-aggregate filling and ball-bearing lubrication effects, optimizing particle packing density, reducing porosity, improving workability, and enhancing compactness. These three types of solid waste complement each other in chemical activation, physical filling, and rheological regulation, jointly achieving a synergistic improvement in mechanical properties, durability, and workability. All three types of industrial solid waste are industrial by-products; their synergistic use can increase waste disposal capacity, reduce the cost of synchronous grouting materials, and decrease cement usage.

[0034] In some embodiments, the persulfate is potassium persulfate or sodium persulfate.

[0035] Persulfate, with its strong electron acceptor ability, can rapidly disrupt the macromolecular network structure of flocculants within minutes of contact with water, releasing the encapsulated cement particles and ensuring full contact between cement and water for a sustained hydration reaction. Hydrogen peroxide decomposes rapidly (especially at high temperatures or in alkaline environments), and its oxidation effect is short-lived, potentially leading to incomplete flocculant destruction, insufficient release of cement particles, slow hydration, and limited strength gain. Furthermore, hydrogen peroxide readily foams, increasing material porosity and reducing density, thus decreasing strength. Dichromates are acidic and corrode unhydrated clinker particles (such as calcium silicate) or hydration products (such as CSH gel), disrupting the structure of hydration products and reducing mechanical properties; they are also toxic.

[0036] After persulfate disrupts the flocculated structure, the released cement particles can synergistically interact with industrial solid waste, accelerating the formation of hydration products. Furthermore, the decomposition of persulfate generates sulfate ions (SO42-). 2+ It contains no heavy metals, toxic gases, or corrosive byproducts, and will not negatively affect the long-term structural stability of the synchronous grouting material.

[0037] In addition, dichromates contain hexavalent chromium, which slowly dissolves over time, polluting the environment and causing the expansion of microcracks inside the cementitious structure, reducing its durability. Residual chloride ions from sodium hypochlorite may cause steel reinforcement corrosion (if used in steel-containing applications), or the introduced sodium ions may cause alkali-aggregate reaction in cement, shortening its service life.

[0038] In a second aspect, the present invention provides a synchronous grouting material, comprising the following components by weight: 1000 parts of flocculated dewatering slag, 100-200 parts of cement, 90-185 parts of the strength deterioration resistance additive mentioned in the first aspect, and 440-600 parts of water.

[0039] In some embodiments, the synchronous grouting material comprises, by weight, the following components: 1000 parts of flocculated dewatering slag, 100-200 parts of cement, 100-183 parts of the strength deterioration resistance additive, and 450-600 parts of water.

[0040] Thirdly, the present invention provides a method for preparing the synchronous grouting material, comprising the following steps: Weigh out the flocculated dewatering slag, cement, strength-degrading additive, and water in the specified proportions. Mix all weighed components thoroughly, and stir for at least 3 minutes. Place the mixed slurry in a storage container for later use, and continue stirring to prevent segregation during settling. When in use, the slurry is pumped to the designated location using pumping equipment and pipelines.

[0041] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are explanations of the present invention and not limitations thereof.

[0042] In the following examples, the flocculated dewatering slag is a by-product of the production of manufactured sand by Qingdao Lvfan Changyun Environmental Protection Building Materials Co., Ltd., with a moisture content of 38.2% and a flocculant content of 0.85% (by mass fraction).

[0043] The cement is Shanshui brand ordinary silicate 425 cement.

[0044] Potassium persulfate, sodium persulfate, cesium hydroxide, rubidium hydroxide, and ferric nitrate all meet national standards.

[0045] Granulated blast furnace slag powder conforms to the national standard S105 grade, with a specific surface area of ​​550 m². 2 / kg; the phosphorus slag powder conforms to the national standard L95 grade, with a specific surface area of ​​550m². 2 / kg; Red mud is a byproduct of the Bayer process, wine-red in color, with a specific surface area of ​​900 m² / kg. 2 / kg; the steel slag powder is grade one conforming to national standards, with a specific surface area of ​​500m². 2 / kg; the amorphous silica in the silica fume has a purity of 92%, is gray, meets national standards, and has a specific surface area of ​​20,000 m². 2 / kg; Ultrafine granulated blast furnace slag powder with a specific surface area of ​​800m² 2 / kg; ultrafine fly ash with a specific surface area of ​​900m² 2 / kg.

[0046] Example 1 A synchronous grouting material, by weight, is composed of the following components: 1000 parts of flocculated dewatered cement slag; 150 parts of ordinary silicate 425 cement; 520 parts of water; 0.2 parts of potassium persulfate; 0.1 parts of cesium hydroxide; 0.2 parts of ferric nitrate; and 150 parts of granulated blast furnace slag powder.

[0047] Example 2 A synchronous grouting material, by weight, is composed of the following components: 1000 parts of flocculated dewatered cement slag; 150 parts of ordinary silicate 425 cement; 520 parts of water; 0.2 parts of sodium persulfate; 0.1 parts of rubidium hydroxide; 0.2 parts of ferric sulfate; 120 parts of granulated blast furnace slag powder; 15 parts of steel slag powder; and 15 parts of ultrafine fly ash.

[0048] Example 3 A synchronous grouting material, by weight, is composed of the following components: 1000 parts of flocculated dewatered cement slag; 150 parts of ordinary silicate 425 cement; 520 parts of water; 0.2 parts of sodium persulfate; 0.1 parts of rubidium hydroxide; 0.2 parts of aluminum nitrate; 120 parts of phosphorus slag powder; 15 parts of red mud; and 15 parts of ultrafine granulated blast furnace slag powder.

[0049] Example 4 A synchronous grouting material, by weight, is composed of the following components: 1000 parts of flocculated dewatered cement slag; 150 parts of ordinary silicate 425 cement; 520 parts of water; 0.2 parts of potassium persulfate; 0.1 parts of cesium hydroxide; 0.2 parts of ferric nitrate; 120 parts of granulated blast furnace slag powder; 15 parts of red mud; and 15 parts of silica fume.

[0050] Comparative Example 1 The difference from Example 4 is that the strength deterioration additive is replaced with cement in equal amounts, while everything else is the same as Example 4.

[0051] The synchronous grouting material in this comparative proportion, by weight, includes 1000 parts of flocculated dewatering slag, 300.5 parts of ordinary silicate 425 cement, and 520 parts of water.

[0052] Comparative Example 2 The difference from Example 4 is that the composition of the anti-strength degradation additive is different from that in Example 4.

[0053] The synchronous grouting material in this comparative proportion, by mass fraction, includes 1000 parts of dewatered slag; 150 parts of ordinary silicate 425 cement; 520 parts of water; 0.5 parts of ammonium persulfate; 0.1 parts of sodium hydroxide; 0.5 parts of zinc sulfate; and 150 parts of granulated blast furnace slag powder.

[0054] Comparative Example 3 The difference from Example 4 is that only an equal amount of potassium persulfate is replaced with hydrogen peroxide, and everything else is the same as in Example 4.

[0055] Comparative Example 4 The difference from Example 4 is that only potassium persulfate is replaced with potassium dichromate in equal amounts; otherwise, they are the same as in Example 4.

[0056] Comparative Example 5 The difference from Example 4 is that only potassium persulfate is replaced with an equal amount of sodium hypochlorite, while everything else is the same as in Example 4.

[0057] Comparative Example 6 The difference from Example 4 is that only cesium hydroxide is replaced with sodium hydroxide in equal amounts; everything else is the same as in Example 4.

[0058] Comparative Example 7 The difference from Example 4 is that only ferric nitrate is replaced with magnesium nitrate in equal amounts, while everything else is the same as in Example 4.

[0059] Comparative Example 8 The difference from Example 4 is that only ferric nitrate is replaced with zinc sulfate in equal amounts; everything else is the same as in Example 4.

[0060] Comparative Example 9 The difference from Example 4 is that only ferric nitrate is replaced with an equal amount of sodium phosphate, and everything else is the same as in Example 4.

[0061] Comparative Example 10 The difference from Example 4 is that only cesium hydroxide is replaced with granulated blast furnace slag powder in equal amounts; otherwise, they are the same as in Example 4.

[0062] Comparative Example 11 The difference from Example 4 is that only the potassium persulfate is replaced with an equal amount of granulated blast furnace slag powder, and everything else is the same as in Example 4.

[0063] Comparative Example 12 The difference from Example 4 is that only ferric nitrate is replaced with granulated blast furnace slag powder in equal amounts; everything else is the same as in Example 4.

[0064] The synchronous grouting materials prepared in Examples 1-4 and Comparative Examples 1-12 were subjected to tests on the truncated cone flowability, consistency value, initial and final setting time, bleeding rate, and compressive strength of the aggregate. The test methods were, in order, truncated cone flowability test, consistency test, setting time determination test, bleeding test, and cubic compressive strength test (40×40×40mm). The test results are shown in Table 1.

[0065] Table 1 Results of synchronous slurry performance tests

[0066] Note 1: The maintenance conditions are standard maintenance conditions; Note 2: The bulk density of the mixture in Example 1 was 1595 kg / m³. 3 Example 4: The bulk density of the mixture was 1625 kg / m³. 3 The bulk density of the mixture in Comparative Example 1 was 1592 kg / m³. 3 The bulk density of the mixture in Comparative Example 2 was 1594 kg / m³. 3 .

[0067] Comparing the formulations of Comparative Example 1 and Examples 1-4, it can be seen that the cement content in Comparative Example 1 accounts for 30.5% of the weight of the dewatered slag, while the cement content in Examples 1-4 accounts for 15% of the weight of the dewatered slag. The amount of water added is the same in both examples, but the cement content is reduced by half. This reduction in cement content represents a decrease in carbon emissions caused by cement production. If producing 1 ton of cement emits approximately 1000 kg of carbon, disposing of 1 ton of dewatered slag reduces carbon emissions caused by cement by more than 150 kg.

[0068] A comparison of the test results of Comparative Example 1 and Example 4 shows that Example 4 is not inferior to Comparative Example 1 in terms of truncated cone flowability, consistency value, initial and final setting time, bleeding rate, and compressive strength of the stone mass. Specifically, the truncated cone flowability is increased by 7.5%, the consistency value by 4.9%, the initial setting time is accelerated by 1.4%, and the final setting time is accelerated by 2.7%, with only a small improvement in the various properties of the mixture compared to Comparative Example 1. The bleeding rate is reduced by 25%. The compressive strength of the stone mass increases by 19% at 3 days, 90% at 7 days, and 136% at 28 days; the compressive strength of the stone mass increases by 143% at 56 days, showing a significant improvement in the mechanical properties and durability of the stone mass compared to Comparative Example 1. The density increases slightly by 2.1%. In summary, compared to Comparative Example 1, Example 4 shows a smaller improvement in the various properties of the mixture, but a significant improvement in the mechanical properties and durability of the stone mass, and higher density.

[0069] A comparison of the test results of Comparative Example 2 and Example 4 shows that Example 4 is not inferior to Comparative Example 2 in terms of truncated cone flowability, consistency value, initial and final setting time, bleeding rate, and compressive strength of the stone body. Specifically, the truncated cone flowability increased by 2.3%, the consistency value increased by 2%, the initial setting time accelerated by 1.1%, and the final setting time accelerated by 1.1%. The improvement in various properties of the mixture compared to Comparative Example 2 was not significant. The bleeding rate decreased by 18%. The compressive strength of the stone body increased by 22.9% at 3 days, 14.4% at 7 days, and 9% at 28 days. The compressive strength of the stone body increased by 9.6% at 56 days, and the mechanical properties of the stone body were significantly improved compared to Comparative Example 2. The density increased slightly by 1.9%. In summary, compared to Comparative Example 2, the improvement in various properties of the mixture in Example 4 was not significant, but the mechanical properties and durability of the stone body were significantly improved, and the density was higher.

[0070] The experimental results of Examples 4 and Comparative Examples 3-9 show that in Comparative Example 3, hydrogen peroxide decomposes rapidly (especially under high temperature or alkaline conditions), and the oxidation effect is short-lasting, which may lead to incomplete destruction of the flocculant, insufficient release of cement particles, slow hydration reaction, and limited strength growth. Furthermore, hydrogen peroxide easily foams, increasing material porosity and reducing density, thereby reducing strength. In Comparative Example 4, dichromate is acidic and corrodes unhydrated clinker particles (such as calcium silicate) or hydration products (such as CSH gel), destroying the structure of hydration products, reducing mechanical properties, and it is also toxic. In Comparative Example 5, sodium hypochlorite residue... Chloride ions may cause steel corrosion (if used in steel-containing components), or the introduced sodium ions may cause cement-alkali aggregate reaction, shortening service life; in Comparative Example 6, sodium hydroxide is weaker in both alkalinity and solubility than cesium hydroxide, so there is a significant difference in the mechanical properties and durability of the stone; in Comparative Example 7, magnesium nitrate has a lower metal cation charge than ferric nitrate, resulting in weaker competitive adsorption capacity, thus the stone performance varies greatly; the same applies to Comparative Example 8, zinc sulfate; in Comparative Example 9, sodium phosphate has only a 1+ metal cation charge, and its competitive adsorption capacity is the weakest in the range of Comparative Examples 7-9, so the stone performance decreases the most in this range.

[0071] In summary, the test results of Example 4 and Comparative Examples 1-12 show that the characteristics of each component of the anti-deterioration additive can effectively promote the hydration reaction of cement in dewatered slag, improve various properties of the mixture, significantly increase the strength and durability of the aggregate, and increase its density. After replacing some components of the present invention, the decrease in slurry performance was relatively small, but the mechanical properties and durability of the aggregate differed significantly. Comparative Example 1, which contained no additives, exhibited the worst performance in both slurry and aggregate properties; Comparative Examples 3-4, due to negative effects, showed a significant decrease in both the mechanical properties and durability of the aggregate; and Comparative Examples 2 and 5-12, because some components lacked the characteristics of the additives of the present invention, showed a significant decrease in both the mechanical properties and durability of the aggregate.

[0072] Compared to traditional cement-based solidification of dewatered slag, this invention achieves significant improvements in the mechanical properties of the aggregate while reducing cement usage by half, without negatively impacting the aggregate's performance. It offers substantial technical and economic advantages. Furthermore, in practical applications, the strength-degrading agent of this invention can be appropriately dosaged based on different application scenarios and flocculant contents in the dewatered slag. According to experimental and engineering experience, higher flocculant content necessitates higher dosages of the strength-degrading agent. When the flocculant content in the dewatered slag is extremely high, cement dosages within the conventional range will fail to solidify, and the permanent strength will not exceed 0.3 MPa. This invention effectively solves this problem. Conversely, excessive dosage of the strength-degrading agent can lead to a decrease in early-stage strength and, to some extent, affect the subsequent strength growth.

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An additive for preventing the deterioration of the strength of flocculated dewatering slag, characterized in that: By weight, it includes the following components: 0.1-2 parts of a strong electron acceptor; 0.1-1 parts of a strong proton acceptor; 0.1-2 parts of high-charge metal ion compounds; 90-180 parts of industrial solid waste; The strong electron acceptor is a persulfate; The strong proton acceptor is cesium hydroxide and / or rubidium hydroxide; The high-charge metal ion compound is selected from at least one of ferric nitrate, ferric sulfate, aluminum nitrate, or aluminum sulfate.

2. The additive for preventing strength degradation of flocculated dewatering slag according to claim 1, characterized in that: By weight, it includes the following components: 0.1-1 part of a strong electron acceptor; Strong proton acceptor agent 0.1-1 part; 0.1-1 part of high-charge metal ion compounds; 100-180 parts of industrial solid waste.

3. The additive for preventing strength degradation of flocculated dewatering slag according to claim 1 or 2, characterized in that: The industrial solid waste consists of general industrial solid waste and ultrafine industrial solid waste. The general industrial solid waste is selected from at least one of granulated blast furnace slag powder and phosphorus slag powder and at least one of red mud and steel slag powder. The ultrafine industrial solid waste is selected from at least one of silica fume, ultrafine granulated blast furnace slag powder or ultrafine fly ash. Preferably, the specific surface area of ​​granulated blast furnace slag powder is 500-600 m². 2 / kg; The specific surface area of ​​phosphorus slag powder is 500-600 m². 2 / kg; The specific surface area of ​​red mud is 850-950 m². 2 / kg; The specific surface area of ​​steel slag powder is 500-600 m². 2 / kg; The specific surface area of ​​silica fume is 18,000-22,000 m². 2 / kg; Ultrafine blast furnace slag powder has a specific surface area of ​​750-850 m². 2 / kg; Ultrafine fly ash has a specific surface area of ​​850-950 m². 2 / kg.

4. The additive for preventing strength degradation of flocculated dewatering slag according to claim 3, characterized in that: The industrial solid waste is a mixture of granulated blast furnace slag powder, steel slag powder and ultrafine fly ash, with a mass ratio of 100-130:10-30:10-30.

5. The additive for preventing strength degradation of flocculated dewatering slag according to claim 3, characterized in that: The industrial solid waste is a mixture of phosphorus slag powder, red mud and ultrafine blast furnace slag powder, with a mass ratio of phosphorus slag powder, red mud and ultrafine blast furnace slag powder of 100-130:10-30:10-30.

6. The additive for preventing strength degradation of flocculated dewatering slag according to claim 3, characterized in that: The industrial solid waste is a mixture of granulated blast furnace slag powder, red mud, and silica fume, with a mass ratio of 100-130:10-30:10-30.

7. The additive for preventing strength degradation of flocculated dewatering slag according to claim 1, characterized in that: The persulfate is potassium persulfate or sodium persulfate.

8. A synchronous grouting material, characterized in that: By weight, it comprises the following components: 1000 parts of flocculated dewatering slag, 100-200 parts of cement, 90-185 parts of the strength deterioration resistance additive as described in any one of claims 1-7, and 440-600 parts of water.

9. The synchronous grouting material according to claim 8, characterized in that: By weight, it comprises the following components: 1000 parts of flocculated dewatering slag, 100-200 parts of cement, 100-183 parts of the aforementioned strength deterioration resistance additive, and 450-600 parts of water.

10. A method for preparing the synchronous grouting material according to any one of claims 7-9, characterized in that: Includes the following steps: Weigh out the flocculated dewatering slag, cement, strength-degrading additive, and water in the specified proportions. Mix all weighed components thoroughly, and stir for at least 3 minutes. Place the mixed slurry in a storage container for later use, and continue stirring to prevent segregation during settling.

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