Coagulant, gasified slag mortar and preparation method thereof

Abstract

The invention relates to the technical field of building materials, in particular to a coagulator, gasified slag mortar and a preparation method thereof. The invention provides a coagulator which is prepared by mixing the following chemical components in percentage by mass: 43%-45% of a C6 polycarboxylate superplasticizer, 27%-32% of sodium lignin sulfonate and 28%-30% of an organic silicon defoaming agent, and the sum of the mass percentages of the chemical components is 100%. The coagulant disclosed by the invention has excellent multiple synergistic effects of water-reducing dispersion, delayed coagulation and water retention and stable air entraining. Aeolian sand, industrial solid waste slag, cement and fly ash are used as raw materials, and the coagulator is applied to preparation of the gasified slag mortar, so that the problem of low utilization rate of gasified slag is solved, the bleeding rate of the gasified slag mortar is remarkably reduced, the initial setting time is shortened, and the early and later compressive strength is improved; the technical problems of slow solidification and low strength of the gasified slag mortar are solved, and an efficient scheme is provided for recycling industrial solid wastes.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a coagulant, gasified slag mortar, and a method for preparing the same. Background Technology

[0002] Gasification slag is a solid waste generated during coal chemical processes. Long-term stockpiling not only occupies large amounts of land but also causes serious environmental pollution. Although gasification slag has been used for roadbed filling or low-strength concrete, its utilization rate is still less than 30%, making it difficult to achieve high-value-added utilization. Gasification slag mortar, as a new type of building material, has broad market prospects. Preparing gasification slag into gasification slag mortar can enable its wider application.

[0003] Furthermore, aeolian sand is widely distributed in arid regions. Due to its fine particles and uniform gradation, its direct use in mortar preparation easily leads to defects such as high bleeding rate and poor strength. Although existing technologies attempt to improve mortar performance using coagulants, the long setting time (initial setting time is usually greater than 4 hours) results in low construction efficiency, and the low compressive strength (7-day compressive strength is usually less than 8 MPa) makes it difficult to meet high strength requirements. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a coagulant, gasification slag mortar, and their preparation method. The invention provides a novel coagulant composed of the following chemical components in the indicated mass percentages: 43%–45% C6 polycarboxylate superplasticizer, 27%–32% sodium lignosulfonate, and 28%–30% organosilicon defoamer, with the sum of the mass percentages of each chemical component being 100%. This invention, by compounding C6 polycarboxylate superplasticizer, sodium lignosulfonate, and organosilicon defoamer, and replacing existing coagulants, solves the technical problems of slow setting (initial setting time typically greater than 4 hours) and low strength (7-day compressive strength typically less than 8 MPa) in gasification slag mortar. Furthermore, the gasification slag mortar prepared using the coagulant of this invention exhibits low bleeding rate and high strength, providing an efficient solution for the resource utilization of industrial solid waste.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The first objective of this invention is to provide a coagulant composed of the following chemical components in mass percentage: 43%–45% C6 polycarboxylate superplasticizer, 27%–32% sodium lignosulfonate, and 28%–30% silicone defoamer, wherein the sum of the mass percentages of each chemical component is 100%; wherein the degree of substitution of the polyether side chains on the C6 polycarboxylate superplasticizer molecular chain is 0.8–1.2; the number-average molecular weight (Mn) of the C6 polycarboxylate superplasticizer is 20,000 g / mol–50,000 g / mol, the weight-average molecular weight (Mw) is 40,000 g / mol–100,000 g / mol, and the molecular weight distribution index (PDI, Mw / Mn) is not greater than 2.5. The degree of substitution of the polyether side chains refers to the average number of polyoxyethylene ether (PEO) side chains grafted onto each monomer unit of the C6 polycarboxylate superplasticizer polymer backbone.

[0006] The C6 polycarboxylic acid superplasticizer with the above-mentioned degree of substitution and molecular weight characteristics can form a molecular conformation with dense hydrophilic side chains and a compact structure in aqueous solution. This gives it a faster adsorption rate and stronger anchoring adsorption capacity, enabling it to quickly form a dense and stable adsorption layer on the surface of cement and gasification slag particles. This not only effectively occupies adsorption sites but also significantly reduces ineffective adsorption. At the same time, the controlled molecular weight and narrow molecular weight distribution (PDI≤2.5) ensure a more uniform molecular structure, thus exhibiting more stable and controllable performance.

[0007] Sodium lignosulfonate functions as a retarder, air-entraining agent, and water-retaining agent. As a byproduct of the papermaking industry (the product of lignin sulfonation), sodium lignosulfonate is a large-volume, inexpensive industrial byproduct. Its use realizes the dual resource utilization concept of treating waste with waste, significantly reducing the preparation cost of coagulants and gasification slag mortar. Although many compounds have single or dual functions, the natural polymer structure of sodium lignosulfonate (a phenylpropane skeleton with sulfonic acid groups, phenolic hydroxyl groups, alcoholic hydroxyl groups, etc.) naturally and evenly combines the triple effects of retarding, air-entraining, and water-retaining, with moderate intensity.

[0008] Preferably, the C6 polycarboxylate superplasticizer is prepared according to the following steps: S1. Using fumaric acid and 4,4'-diaminodiphenyl ether as raw materials, fumaric acid solution is added dropwise to 4,4'-diaminodiphenyl ether solution to carry out polycondensation reaction to obtain polyamic acid compound.

[0009] S2. Using polyamic acid compound and 4-aminobutyric acid as raw materials, the 4-aminobutyric acid solution is added dropwise to the polyamic acid compound solution to carry out an amidation reaction, generating amide bonds, thereby grafting 4-aminobutyric acid onto the polyamic acid compound chain to protect the carboxyl group. After removing the solvent, recrystallization is performed to obtain a side-chain functionalized polyamide prepolymer.

[0010] S3. Mix methyl allyl polyoxyethylene ether (HPEG, Mw = 2000 g / mol ~ 2500 g / mol), reducing agent, and chain transfer agent to obtain a mixture. Add side-chain functionalized polyamide prepolymer and acrylic acid dropwise to the mixture to carry out a free radical copolymerization reaction, obtaining a liquid mother liquor of polycarboxylate superplasticizer. The number-average molecular weight (Mn) of the polycarboxylate superplasticizer liquid mother liquor is 10000 g / mol ~ 50000 g / mol, the weight-average molecular weight (Mw) is 20000 g / mol ~ 100000 g / mol, and the molecular weight distribution index (PDI = Mw / Mn) is not greater than 2.5. By controlling the type and amount of chain transfer agent, the molecular weight and its distribution can be adjusted, thereby obtaining a polycarboxylate superplasticizer liquid mother liquor with excellent adsorption performance and stable dispersion effect.

[0011] S4. Mix the liquid mother liquor of polycarboxylate superplasticizer, filler, and additives, and then dry the mixture to obtain C6 polycarboxylate superplasticizer. The filler is selected from at least one of sodium sulfate, fly ash, mineral powder, silica fume, cement, quartz powder, limestone powder, and bentonite.

[0012] Preferably, the coagulant is a mixture of the following chemical components by mass percentage: 43% C6 polycarboxylate superplasticizer, 29% sodium lignosulfonate, and 28% silicone defoamer.

[0013] Preferably, the mass ratio of fumaric acid to 4,4'-diaminodiphenyl ether is 1:0.8~0.87.

[0014] Preferably, the mass ratio of the polyamic acid compound to 4-aminobutyric acid is 1:0.44~0.48.

[0015] Preferably, the mass ratio of methyl allyl polyoxyethylene ether, acrylic acid, and side-chain functionalized polyamide prepolymer is 100:9.6~11:1.2~2.4.

[0016] Preferably, the mass ratio of methyl allyl polyoxyethylene ether, reducing agent, and chain transfer agent is 100:0.03~0.04:0.07~0.09. The chain transfer agent is used to control and adjust the molecular weight and molecular weight distribution of the polycarboxylate superplasticizer liquid mother liquor.

[0017] Preferably, the conditions for the polycondensation reaction are as follows: under nitrogen protection, the 4,4'-diaminodiphenyl ether solution is cooled to 5°C~8°C, and then fumaric acid solution is added dropwise to the 4,4'-diaminodiphenyl ether solution for 50 min~150 min; after the addition is completed, the reaction is stirred at 85°C~90°C for 1 h~2.5 h.

[0018] Preferably, the conditions for the amidation reaction are as follows: under nitrogen protection, the polyamic acid compound solution is heated to 35℃~50℃, and then 4-aminobutyric acid solution is added dropwise to the polyamic acid compound solution for 2h~4h; after the addition is completed, the reaction is stirred at 65℃~75℃ for 90min~150min.

[0019] Preferably, the recrystallization operation is as follows: the product obtained by amidation reaction of polyamic acid compound and 4-aminobutyric acid is washed with deionized water and dispersed in ethyl acetate, and stirred at 60℃~75℃ for 1.5h~2h.

[0020] Preferably, the conditions for the free radical copolymerization reaction are as follows: under nitrogen protection, the mixture is heated to 60℃~65℃, and the side-chain functionalized polyamide prepolymer and acrylic acid are added dropwise to the mixture for 1.5h~3h; after the addition is completed, the mixture is stirred at 65℃~70℃ for 2.5h~3h.

[0021] Preferably, in step S4, the preparation of the C6 polycarboxylic acid water-reducing agent is carried out by spray drying, with an inlet temperature of 180℃~200℃ and an outlet temperature of 80℃~90℃.

[0022] Preferably, the additives are selected from at least one of defoamers, retarders, air-entraining agents, early-strength agents, water-retaining agents, and shrinkage-reducing agents; wherein the retarder is selected from sodium gluconate, citric acid, or calcium gluconate; the air-entraining agent is selected from rosin thermal polymer or sodium dodecyl sulfate; and the early-strength agent is selected from triethanolamine, calcium formate, or calcium nitrate.

[0023] Preferably, the reducing agent is selected from ascorbic acid, sodium bisulfite, sodium formaldehyde sulfoxylate, ferrous sulfate, or sodium ascorbate.

[0024] Preferably, the chain transfer agent is selected from at least one of thiopropionic acid, mercaptoethanol, mercaptoacetic acid, and isooctyl 2-mercaptopropionic acid.

[0025] Preferably, the silicone defoamer is selected from at least one of polydimethylsiloxane, polyether-modified polydimethylsiloxane, and hydroxyl-terminated polydimethylsiloxane.

[0026] A second objective of this invention is to provide a method for preparing the aforementioned coagulant, comprising the following steps: A coagulant is obtained by mixing C6 polycarboxylate superplasticizer, sodium lignosulfonate, and organosilicon defoamer in a mass ratio of 40~45:25~32:25~30.

[0027] The third objective of this invention is to provide a gasification slag mortar, which is prepared using the aforementioned coagulant. The gasification slag mortar is composed of a dry mix and water, with a water-to-dry mix mass ratio of 0.08 to 0.12:1. Based on 100g, the dry mix consists of 45g to 55g of gasification slag, 25g to 35g of aeolian sand, 12g to 20g of cement, 2g to 6g of fly ash, and 0.1g to 0.2g of coagulant.

[0028] Preferably, based on 100g, the dry mix consists of 49.94g of gasification slag, 29.96g of aeolian sand, 15.98g of cement, 4g of fly ash and 0.12g of coagulant.

[0029] Preferably, the cement is selected from silicate cement, more preferably 42.5R silicate cement.

[0030] Preferably, the fly ash is selected from Grade I fly ash or Grade II fly ash.

[0031] Preferably, the particle size of the aeolian sand is 0.15mm to 2.36mm.

[0032] The fourth object of the present invention is to provide a method for preparing the above-mentioned gasification slag mortar, comprising the following steps: According to the above material ratio, the coagulant is dissolved in water to obtain a coagulant solution; gasification slag, aeolian sand, cement and fly ash are mixed to obtain a mixture; the mixture is then mixed with the coagulant solution to obtain gasification slag mortar.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a coagulant composed of 43%~45% C6 polycarboxylate superplasticizer, 29%~32% sodium lignosulfonate, and 28%~30% organosilicon defoamer, wherein the sum of the mass percentages of each chemical component is 100%. The coagulant prepared by this invention through the compounding of C6 polycarboxylate superplasticizer, sodium lignosulfonate, and organosilicon defoamer exhibits excellent synergistic effects of water reduction and dispersion, retarding and water retention, and stable air entrainment. Its application in the preparation of gasification slag mortar solves the technical problems of slow setting and low strength in gasification slag mortar, providing an efficient solution for the resource utilization of industrial solid waste.

[0034] 2. This invention also provides a gasification slag mortar, which is composed of a dry mix and water, with a water-to-dry mix mass ratio of 0.08~0.12:1. Based on 100g, the dry mix consists of 45g~55g of gasification slag, 25g~35g of aeolian sand, 12g~20g of cement, 2g~6g of fly ash, and 0.1g~0.2g of coagulant. This invention uses aeolian sand, industrial solid waste gasification slag, cement, and fly ash as raw materials. Through optimizing the raw material ratio and the synergistic effect of the coagulant, it achieves an improvement in the comprehensive performance of the gasification slag mortar. This not only solves the problem of low utilization rate of gasification slag but also significantly reduces the bleeding rate of the mortar, shortens the initial setting time, and improves the early and later compressive strength, thus solving the technical problems of slow setting and low strength of gasification slag mortar.

[0035] In this process, the C6 polycarboxylate superplasticizer and sodium lignosulfonate in the coagulant work together to highly disperse cement and fly ash particles, forming a stable suspension system that locks in free water. Sodium lignosulfonate acts like a sponge, trapping moisture and preventing it from seeping out. The beneficial microbubbles retained by the microbubbles and defoamer act as lubricants between particles, while simultaneously blocking the channels for water seepage.

[0036] 3. Compared to existing coagulants, the coagulant of this invention is a powder, which offers lower costs in transportation and storage, significantly improved stability and shelf life, flexible and controllable use, and excellent environmental friendliness and safety. This is attributed to its powder form, which eliminates the need for liquid packaging and avoids the risks of freezing or sedimentation. Furthermore, the powder exhibits stronger weather resistance and component stability, with a more compact molecular structure, resulting in a 5% to 8% higher water reduction rate compared to liquid products at the same dosage. In addition, the powder can be packaged in recyclable woven bags, avoiding the specialized processing required for liquid packaging containers and better meeting green environmental protection requirements. Detailed Implementation

[0037] The technical solution of the present invention will be clearly and completely described below with reference to the data in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. It should be noted that the technical terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of the present invention can be purchased from the market or prepared by existing methods. Among them, the gasification slag of the present invention is water-washed gasification slag, that is, the solid waste remaining after the slag produced in the coal gasification process is washed with water to remove some impurities and unreacted substances. The particle size of the water-washed gasification slag is ≤5mm, and the particle size of the aeolian sand is 0.15mm~2.36mm; the cement is 42.5R silicate cement; the fly ash is Class II fly ash; polydimethylsiloxane was purchased from Jinan Longcheng Organosilicon Co., Ltd.; the organosilicon defoamer was purchased from the organosilicon defoamer sample provided by Shandong Furman New Material Co., Ltd.

[0038] In existing technologies, gasification slag mortar has the disadvantages of long setting time and low compressive strength. In addition, the utilization rate of industrial solid waste is low, and the aeolian sand has high bleeding rate and poor strength due to its fine particles and single gradation.

[0039] To address these problems, this invention provides a coagulant composed of the following chemical components in the indicated mass percentages: 43%–45% C6 polycarboxylate superplasticizer, 29%–32% sodium lignosulfonate, and 28%–30% organosilicon defoamer, with the sum of the mass percentages of each chemical component being 100%. The degree of substitution of the polyether side chains in the C6 polycarboxylate superplasticizer molecular chain is 0.8–1.2. Applying this coagulant to the preparation of gasification slag mortar, using aeolian sand, industrial solid waste gasification slag, cement, and fly ash as raw materials, and through optimizing the raw material ratio and the synergistic effect of the coagulant, the overall performance of the gasification slag mortar is improved. This not only solves the problem of low utilization rate of gasification slag but also significantly reduces the bleeding rate of the gasification slag mortar, shortens the initial setting time, and improves the early and later compressive strength, thus solving the technical problems of slow setting and low strength of gasification slag mortar.

[0040] Specifically, the initial setting time is shortened to 1.3-1.5 hours through the dispersing effect of C6 polycarboxylate superplasticizer, while the 7-day compressive strength is increased to over 30 MPa (Example 1). Sodium lignosulfonate further optimizes the water-reducing effect, and organosilicon defoamer precisely eliminates harmful large air bubbles, significantly reducing the bleeding rate (4.8%-6.3%) and optimizing the pore structure. The synergistic effect of these three agents overcomes the technical bottlenecks of low strength (7-day compressive strength is usually less than 8 MPa) and slow setting (initial setting time is usually greater than 4 hours) in existing technologies. While significantly improving the early and late compressive strength, it solves the problem of long setting time, extends the workable time of the mortar, realizes high-value utilization of industrial solid waste, and significantly improves the comprehensive performance of gasification slag mortar.

[0041] To enable those skilled in the art to more clearly understand the technical solution of the present invention, the following will describe it in detail with reference to specific embodiments: Example 1 A method for preparing a coagulant, comprising the following steps: S1. Preparation of C6 polycarboxylic acid superplasticizer: S11. 50g of fumaric acid was dispersed in 200mL of N,N-dimethylformamide, heated to 40℃, and stirred at 40℃ for 15min. Then, it was naturally cooled to room temperature to obtain a fumaric acid solution. 43.5g of 4,4'-diaminodiphenyl ether was dispersed in 200mL of N,N-dimethylformamide and cooled to 6℃ under nitrogen protection to obtain a 4,4'-diaminodiphenyl ether solution. The fumaric acid solution was added dropwise to the 4,4'-diaminodiphenyl ether solution over 100min. After the addition was completed, the mixture was stirred at 90℃ for 2h. After the reaction was completed, N,N-dimethylformamide was evaporated under vacuum to obtain a polyamic acid compound.

[0042] S12. 80g of polyamic acid compound was dispersed in 200mL of N,N-dimethylformamide, heated to 50℃, and stirred at 50℃ for 30min to obtain a polyamic acid compound solution; 36.8g of 4-aminobutyric acid was dissolved in 200mL of N,N-dimethylformamide to obtain a 4-aminobutyric acid solution; under nitrogen protection, the 4-aminobutyric acid solution was added dropwise to the polyamic acid compound solution over a period of 3h; after the addition was completed, the temperature was raised to 70℃, and the reaction was stirred at 70℃ for 150min; after the reaction was completed, N,N-dimethylformamide was removed by rotary evaporation, the obtained product was washed with deionized water, dispersed in ethyl acetate, stirred at 70℃ for 2h, and the solid was collected after recrystallization. The solid was then vacuum dried at 60℃ to constant weight to obtain a side-chain functionalized polyamide prepolymer.

[0043] S13. Mix 100g of methyl allyl polyoxyethylene ether (HPEG) with 130mL of deionized water, heat to 60℃~65℃, and stir for 5min~15min; add 0.03g of ascorbic acid and 0.08g of thiopropionic acid, and then, under nitrogen protection, add dropwise a mixture of 10.43g of acrylic acid and 2.4g of side-chain functionalized polyamide prepolymer over a period of 3h; after the addition is complete, continue the reaction at 70℃ for 3h to obtain a mixed solution; after the reaction is complete, adjust the solid content of the mixed solution to 41% by vacuum evaporation, and then cool naturally to room temperature to obtain a liquid mother liquor of polycarboxylate superplasticizer.

[0044] S14. Mix 275g of polycarboxylate superplasticizer liquid mother liquor with 20g of sodium gluconate (retarder), 3g of fumed silica (filler silica fume) and 8g of citric acid (retarder) to obtain a mixture. Adjust the solid content of the mixture to 45%. Then set the inlet temperature to 190℃ and the outlet temperature to 90℃ for spray drying. After drying, collect the powder through a cyclone separator and pass it through an 80-mesh sieve to obtain C6 polycarboxylate superplasticizer with a moisture content of no more than 1.5%.

[0045] S2. Preparation of coagulant: The C6 polycarboxylate superplasticizer, sodium lignosulfonate, and polydimethylsiloxane were mixed in the following mass percentages: 43% C6 polycarboxylate superplasticizer, 29% sodium lignosulfonate, and 28% polydimethylsiloxane emulsion. The mixture was stirred thoroughly to obtain a coagulant.

[0046] S3. Preparation of a gasification slag mortar: S31. Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain a mixture.

[0047] S32. Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0048] Example 2 A method for preparing a coagulant, which is the same as the preparation steps in Example 1, except that the amounts of C6 polycarboxylic acid superplasticizer, sodium lignosulfonate, and polydimethylsiloxane emulsion are different in step S2, includes the following steps: The C6 polycarboxylate superplasticizer, sodium lignosulfonate, and polydimethylsiloxane emulsion were mixed in the following mass percentages: 45% C6 polycarboxylate superplasticizer, 27% sodium lignosulfonate, and 28% polydimethylsiloxane emulsion. The mixture was stirred thoroughly to obtain a coagulant.

[0049] S3. A method for preparing gasified slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0050] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0051] Example 3 A method for preparing a coagulant is the same as the preparation steps in Example 1, except that in step S11, the amount of 4,4'-diaminodiphenyl ether is replaced from 43.5g to 40g to obtain the coagulant.

[0052] A method for preparing gasification slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0053] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0054] Example 4 A method for preparing a coagulant is the same as the preparation steps in Example 1, except that in step S12, the amount of 4-aminobutyric acid is replaced from 36.8g to 38.4g to obtain the coagulant.

[0055] A method for preparing gasification slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0056] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0057] Example 5 A method for preparing a coagulant is the same as the preparation steps in Example 1, except that in step S12, the amount of 4-aminobutyric acid is replaced from 36.8g to 35.5g to obtain the coagulant.

[0058] A method for preparing gasification slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0059] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0060] Example 6 A method for preparing a coagulant is the same as the preparation steps in Example 1, except that in step S13, the amount of ascorbic acid is replaced from 0.03g to 0.04g, and the amount of thiopropionic acid is replaced from 0.08g to 0.07g, thus obtaining the coagulant.

[0061] A method for preparing gasification slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0062] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0063] Example 7 A method for preparing a coagulant is the same as the preparation steps in Example 1, except that the amount of thiopropionic acid in step S13 is replaced from 0.08g to 0.09g to obtain the coagulant.

[0064] A method for preparing gasification slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0065] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0066] Example 8 A method for preparing a coagulant is the same as the preparation steps in Example 1, except that in step S13, the amount of acrylic acid is replaced from 10.43g to 9.6g, and the amount of side-chain functionalized polyamide prepolymer is replaced from 2.4g to 1.2g, thus obtaining the coagulant.

[0067] A method for preparing gasification slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0068] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0069] Example 9 A method for preparing a coagulant is the same as the preparation steps in Example 1, except that in step S13, the amount of acrylic acid is replaced from 10.43g to 11g to obtain the coagulant.

[0070] A method for preparing gasification slag mortar: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0071] Mix 200g of water and 2g of coagulant to obtain a coagulant solution; add the coagulant solution to the mixture and stir for 4 minutes to obtain gasified slag mortar.

[0072] Comparative Example 1 A method for preparing gasification slag mortar is the same as the method in Example 1, except that no coagulant is added, and includes the following steps: Mix 1000g of water-washed gasification slag, 520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0073] Comparative Example 2 A method for preparing ordinary aeolian sand mortar, the method comprising the following steps: Mix 1520g of aeolian sand, 400g of 42.5R silicate cement and 80g of Grade II fly ash, and stir for 2 minutes to obtain the mixture.

[0074] Add 200g of water to the mixture and stir for 4 minutes to obtain ordinary aeolian sand mortar.

[0075] Examples 1 to 9 of this invention all yielded coagulants and gasified slag mortars with parallel effects. The polarity properties of the gasified slag mortars from Examples 1 and 2 are studied below: Performance testing: The compressive strength of the gasified slag mortars in Examples 1-2 and Comparative Examples 1-2 was tested according to GB / T 17671, and the bleeding rate was tested according to GB / T 50080. The results are shown in Table 1. Table 1 shows the test results of the gasified slag mortar performance of Examples 1-2 and Comparative Examples 1-2. The results in Table 1 show that the coagulant of the present invention significantly shortens the initial setting time of gasified slag mortar, improves compressive strength, and reduces bleeding rate.

[0076] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range, as well as any value between the two endpoints, can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

Claims

1. A coagulant, characterized in that, The coagulant is a mixture of the following chemical components by mass percentage: 43%~45% C6 polycarboxylate superplasticizer, 27%~32% sodium lignosulfonate, and 28%~30% silicone defoamer, and the sum of the mass percentages of each chemical component is 100%. The degree of substitution of the polyether side chain in the C6 polycarboxylic acid water-reducing agent molecular chain is 0.8~1.2; The number average molecular weight of the C6 polycarboxylate superplasticizer is 20,000 g / mol to 50,000 g / mol, the weight average molecular weight is 40,000 g / mol to 100,000 g / mol, and the molecular weight distribution index is not greater than 2.

5.

2. The coagulant according to claim 1, characterized in that, C6 polycarboxylate superplasticizer is prepared according to the following steps: Using fumaric acid and 4,4'-diaminodiphenyl ether as raw materials, a fumaric acid solution was added dropwise to a 4,4'-diaminodiphenyl ether solution to carry out a polycondensation reaction, thereby obtaining a polyamic acid compound; Using polyamic acid compounds and 4-aminobutyric acid as raw materials, 4-aminobutyric acid is added dropwise to the polyamic acid compound to carry out an amidation reaction to generate amide bonds, thereby grafting 4-aminobutyric acid as a functional spacer group onto the polyamic acid compound chain to obtain a side-chain functionalized polyamide prepolymer. A mixture of methyl allyl polyoxyethylene ether, a reducing agent, and a chain transfer agent is obtained; a side-chain functionalized polyamide prepolymer and acrylic acid are added dropwise to the mixture to carry out a free radical copolymerization reaction, resulting in a liquid mother liquor of polycarboxylate superplasticizer; The liquid mother liquor of polycarboxylate superplasticizer, filler and additives are mixed and dried to obtain C6 polycarboxylate superplasticizer; The filler is selected from at least one of sodium sulfate, fly ash, mineral powder, silica fume, cement, quartz powder, limestone powder, and bentonite. The additives are selected from at least one of the following: defoamer, retarder, air-entraining agent, early-strength agent, water-retaining agent, and shrinkage-reducing agent.

3. The coagulant according to claim 1, characterized in that, The mass ratio of fumaric acid to 4,4'-diaminodiphenyl ether is 1:0.8~0.

87.

4. The coagulant according to claim 1, characterized in that, The mass ratio of polyamic acid compound to 4-aminobutyric acid is 1:0.44~0.

48.

5. The coagulant according to claim 1, characterized in that, The mass ratio of methyl allyl polyoxyethylene ether, acrylic acid, and side-chain functionalized polyamide prepolymer is 100:9.6~11:1.2~2.

4.

6. The coagulant according to claim 1, characterized in that, The mass ratio of methyl allyl polyoxyethylene ether, reducing agent and chain transfer agent is 100:0.03~0.04:0.07~0.

09.

7. The coagulant according to claim 1, characterized in that, The organosilicon defoamer is selected from at least one of polydimethylsiloxane, polyether-modified polydimethylsiloxane, and hydroxyl-terminated polydimethylsiloxane.

8. A gasification slag mortar, characterized in that, The gasification slag mortar, prepared using the coagulant described in claim 1, is composed of dry mix and water, with a water-to-dry mix mass ratio of 0.08 to 0.12:

1. Based on 100g, the dry mix consists of 45g~55g of gasification slag, 25g~35g of aeolian sand, 12g~20g of cement, 2g~6g of fly ash and 0.1g~0.2g of coagulant.

9. The gasification slag mortar according to claim 8, characterized in that, The dry mix is ​​made from the following chemical components in parts by weight: 49.94g of gasification slag, 29.96g of aeolian sand, 15.98g of cement, 4 parts of fly ash, and 0.12g of coagulant.

10. A method for preparing gasified slag mortar according to claim 8, characterized in that, Includes the following steps: Dissolve the coagulant in water to obtain a coagulant solution; Gasification slag, aeolian sand, cement and fly ash are mixed to obtain a mixture; The mixture is combined with the coagulant solution to obtain gasified slag mortar.

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