A coal-based solid waste-based ultra-high water filling material and its preparation method

Abstract

The present invention discloses a coal-based solid waste-based ultra-high water filling material and a preparation method thereof. The filling material can improve the utilization rate of coal-based solid waste, reduce the material cost, and at the same time improve the stability and strength of the material, and enhance the environmental adaptability. The filling material consists of component A and component B. Among them, component A includes the following components: sulfoaluminate clinker, citric acid and iron ethylene diamine tetra(methylene phosphonic acid); component B includes the following components: desulfurized gypsum, fly ash, aluminum sulfate, N-(2-nitrophenyl) ethanolamine, and triisopropoxy titanium chloride complex.

Description

Technical Field

[0001] The present invention relates to the technical field of special mine filling materials, and particularly to a coal-based solid waste-based ultra-high water filling material and a preparation method thereof. Background Art

[0002] Ultra-high water filling material (also known as ultra-high water cementitious filling material) is a new type of coal mine filling material. Its characteristic is that in the formed consolidated body, the volume ratio of water exceeds 90%, while the volume occupied by the material itself is less than 10%. This material is usually prepared from bauxite and gypsum as the main raw materials through specific proportioning and treatment processes. Ultra-high water filling materials are mainly used for filling mining in coal mines, especially widely used in large-scale filling mining of "under three types of surface" coal seams. In addition, ultra-high water filling materials are also used in fields such as pre-filling gob in coal mine working faces, fire prevention, gob-side entry retaining, ground fissure treatment, and grouting modification of aquifers.

[0003] In dealing with coal-based solid wastes, traditional ultra-high water filling materials have some problems, such as low solid waste utilization rate, insufficient material stability and strength, poor environmental adaptability, etc. In addition, traditional processes may have problems such as high energy consumption, high preparation cost, and complex construction. Summary of the Invention

[0004] The embodiments of the present application provide a coal-based solid waste-based ultra-high water filling material and a preparation method thereof. This filling material can improve the utilization rate of coal-based solid wastes, reduce the material cost, while improving the stability and strength of the material, and enhancing the environmental adaptability.

[0005] The present invention provides a coal-based solid waste-based ultra-high water filling material. The filling material is composed of component A and component B. Among them, component A includes the following components: sulfoaluminate clinker, citric acid, and iron ethylene diamine tetra(methylene phosphonic acid); component B includes the following components: desulfurized gypsum, fly ash, aluminum sulfate, N-(2-nitrophenyl) ethanolamine, and triisopropoxy titanium chloride complex.

[0006] In some embodiments, each component in component A is included by mass parts: 100 parts of sulfoaluminate clinker, 0.2 - 0.4 parts of citric acid, and 0.01 - 0.02 parts of iron ethylene diamine tetra(methylene phosphonic acid).

[0007] In some embodiments, each component in component B is included by mass parts: 40 - 60 parts of desulfurized gypsum, 35 - 50 parts of fly ash, 5 - 10 parts of aluminum sulfate, 0.1 - 2 parts of N-(2-nitrophenyl) ethanolamine, and 0.02 - 0.1 parts of triisopropoxy titanium chloride complex.

[0008] The present invention also provides a preparation method of a coal-based solid waste-based ultra-high water filling material, including:

[0009] Mix the first component with water to form a first mixed slurry;

[0010] Mix the second component with water to form a second mixed slurry;

[0011] Mix the first mixed slurry and the second mixed slurry to form a coal-based solid waste-based ultra-high water filling material.

[0012] In some embodiments, the first component and water are mixed in a mass ratio of 1:(5 - 7) to form a first mixed slurry.

[0013] In some embodiments, the second component and water are mixed in a mass ratio of 1:(5 - 7) to form a second mixed slurry.

[0014] In some embodiments, the first mixed slurry and the second mixed slurry are mixed in a mass ratio of 1:(0.5 - 2) to form a coal-based solid waste-based ultra-high water filling material.

[0015] A coal-based solid waste-based ultra-high water filling material and a preparation method thereof provided by the present invention can improve the utilization rate of coal-based solid waste, reduce the material cost, and at the same time improve the stability and strength of the material, and enhance the environmental adaptability. Description of the Drawings

[0016] Figure 1 Exemplarily shows a flowchart of a preparation method of a coal-based solid waste-based ultra-high water filling material provided according to some embodiments. Detailed Embodiments

[0017] To better understand the above technical solutions, the technical solutions of the present application will be described in detail through specific embodiments.

[0018] To solve the above technical problems, an embodiment of the present application provides a coal-based solid waste-based ultra-high water filling material, which can improve the utilization rate of coal-based solid waste, reduce the material cost, and at the same time improve the stability and strength of the material, and enhance the environmental adaptability.

[0019] The filling material is composed of a first component and a second component. Among them, the first component includes the following components: sulfoaluminate clinker, citric acid, and iron ethylenediaminetetra(methylene phosphonic acid); the second component includes the following components: desulfurized gypsum, fly ash, aluminum sulfate, N-(2-nitrophenyl)ethanolamine, and triisopropoxy titanium chloride complex.

[0020] In the embodiment of the present application, the sulfoaluminate clinker is the main component of the first component and plays a role in hydrating to form an ettringite skeleton. Citric acid is a retarder, which mainly delays the hydration of the sulfoaluminate clinker to make the first component meet the time requirements specified in the DB13T 1660-2012 standard for ultra-high water materials for mine use.

[0021] Ferric ethylenediaminetetra(methylenephosphonic acid) acts as a strengthening agent and a suspending agent. Ferric ethylenediaminetetra(methylenephosphonic acid) is a macromolecule that can be suspended in the A component to increase the skeletal effect of the slurry. At the same time, the amino groups in this molecule can promote the dissolution and hydration of sulfoaluminate clinker, and increase the strength of the high-water filling material in the later stage.

[0022] Desulfurized gypsum and fly ash are the main components of the B component. Desulfurized gypsum mainly provides calcium ions and sulfate ions, and fly ash mainly provides hydroxide ions and calcium ions, providing the sources of calcium ions, hydroxide ions and sulfate ions for the formation of ettringite. The formation formula of ettringite is as follows:

[0023] C4A3$(sulfoaluminate clinker) + 8C$·2H(desulfurized gypsum) + 6CH(calcium hydroxide, provided by fly ash) + 74H → 3C6A$3H32(ettringite).

[0024] Aluminum sulfate is a coagulant, which serves the purpose of forming trace amounts of ettringite with calcium oxide in fly ash. The specific formula is as follows: 4CaO + 32H2O + Al2(SO4)3 = 3C6A$3H32(AFt). The trace amounts of ettringite formed here can serve as crystal seeds. When the A component and the B component are mixed, they can make the filling material solidify quickly, thus meeting the requirements for the setting time after mixing in the standard.

[0025] N-(2-nitrophenyl)ethanolamine is a suspending agent and a catalyst. Because the ultra-high-water filling material has a very high water content and is prone to bleeding after mixing, after adding N-(2-nitrophenyl)ethanolamine, when the A component and the B component are mixed, both N-(2-nitrophenyl)ethanolamine and ferric ethylenediaminetetra(methylenephosphonic acid) contain amino groups, and hydrogen bonds can be formed between them and the crystal water in ettringite, linking with each other to form a three-dimensional network structure, reducing bleeding and skeletal pores, and improving the stability and strength of the filling material.

[0026] The titanium ions in the triisopropoxytitanium chloride complex have empty electron orbitals and can form coordination bonds with the atoms with lone pair electrons in the N-(2-nitrophenyl)ethanolamine molecule to enhance the chemical property activity of this substance. When mixed with the A component, when the activated N-(2-nitrophenyl)ethanolamine coexists with ferric ethylenediaminetetra(methylenephosphonic acid), it will interact with the iron ions or ethylenediaminetetra(methylenephosphonic acid) molecules therein, further enhancing the complexation and latching ability of the entire system. At the same time, the titanium ions interact with substances such as sulfoaluminate clinker, desulfurized gypsum or calcium hydroxide to promote the reaction and accelerate the formation rate of ettringite.

[0027] In some embodiments, each component in the A component includes, by mass parts: 100 parts of sulfoaluminate clinker, 0.2 - 0.4 parts of citric acid, and 0.01 - 0.02 parts of ferric ethylenediaminetetra(methylenephosphonic acid).

[0028] In the embodiments of the present application, when the mass fraction of citric acid exceeds 0.4 parts, it will cause too long setting time, which is not conducive to the setting after mixing. If it is too little, it cannot meet the requirement of retarding to the specified time. If the dosage of iron ethylenediaminetetra(methylene phosphonic acid) is too large, it will cause material waste and high cost, and if the dosage is too small, it will not achieve the expected effect.

[0029] In some embodiments, each component in the component B includes, by mass: 40 - 60 parts of desulfurized gypsum, 35 - 50 parts of fly ash, 5 - 10 parts of aluminum sulfate, 0.1 - 2 parts of N-(2-nitrophenyl) ethanolamine, and 0.02 - 0.1 part of triisopropoxy titanium chloride complex.

[0030] The ratio of desulfurized gypsum to fly ash can be adjusted mutually, but beyond this ratio, more other admixtures are needed to adjust the performance of the mixed slurry. For example, when the fly ash is too high or too low, the setting after mixing will become slower, and more aluminum sulfate or N-(2-nitrophenyl) ethanolamine needs to be added for adjustment. If the dosage of aluminum sulfate is too large, it will cause material waste and high cost, and if the dosage is too small, it will not achieve the expected effect. If the dosage of N-(2-nitrophenyl) ethanolamine is too large, it will cause material waste and high cost, and if the dosage is too small, it will not achieve the expected effect.

[0031] The present invention also provides a preparation method of a coal-based solid waste-based ultra-high water filling material. Figure 1 The flowchart of a preparation method of a coal-based solid waste-based ultra-high water filling material provided according to some embodiments is exemplarily shown, and the preparation method includes S100 - S300.

[0032] S100: Mix the component A with water to form a first mixed slurry; in some embodiments, mix the component A with water according to a mass ratio of 1:(5 - 7) to form a first mixed slurry.

[0033] S200: Mix the component B with water to form a second mixed slurry; in some embodiments, mix the component B with water according to a mass ratio of 1:(5 - 7) to form a second mixed slurry.

[0034] S300: Mix the first mixed slurry and the second mixed slurry to form a coal-based solid waste-based ultra-high water filling material. In some embodiments, mix the first mixed slurry and the second mixed slurry according to a mass ratio of 1:(0.5 - 2) to form a coal-based solid waste-based ultra-high water filling material.

[0035] The following examples and comparative examples illustrate that the coal-based solid waste-based ultra-high water filling material in the embodiments of the present application has good performance. The test materials used in the following examples are all obtained from conventional stores and other channels without special instructions. In the following quantitative tests of the examples, three repeated experiments are set, and the data are the average values or average values ± standard deviations of the three repeated experiments.

[0036] Example 1

[0037] By mass, 100 parts of sulphoaluminate clinker, 0.2 parts of citric acid and 0.01 part of iron ethylenediaminetetra(methylene phosphonic acid) are mixed to obtain component A;

[0038] By mass, 40 parts of desulphurized gypsum, 50 parts of fly ash, 10 parts of aluminium sulphate, 0.1 part of N-(2-nitrophenyl) ethanolamine and 0.1 part of triisopropoxy titanium chloride complex are mixed to obtain component B;

[0039] By mass, 1 part of component A is mixed with 5 parts of water to form a first mixed slurry;

[0040] By mass, 1 part of component B is mixed with 5 parts of water to form a second mixed slurry;

[0041] By mass, the first mixed slurry and the second mixed slurry are mixed to form a coal-based solid waste-based ultra-high water filling material.

[0042] Example 2

[0043] By mass, 100 parts of sulphoaluminate clinker, 0.4 parts of citric acid and 0.02 part of iron ethylenediaminetetra(methylene phosphonic acid) are mixed to obtain component A;

[0044] By mass, 60 parts of desulphurized gypsum, 35 parts of fly ash, 5 parts of aluminium sulphate, 0.2 part of N-(2-nitrophenyl) ethanolamine and 0.05 part of triisopropoxy titanium chloride complex are mixed to obtain component B;

[0045] By mass, 1 part of component A is mixed with 5 parts of water to form a first mixed slurry;

[0046] By mass, 1 part of component B is mixed with 5 parts of water to form a second mixed slurry;

[0047] By mass, the first mixed slurry and the second mixed slurry are mixed to form a coal-based solid waste-based ultra-high water filling material.

[0048] Example 3

[0049] By mass, 100 parts of sulphoaluminate clinker, 0.4 parts of citric acid and 0.02 part of iron ethylenediaminetetra(methylene phosphonic acid) are mixed to obtain component A;

[0050] Mix 45 parts of desulfurized gypsum, 45 parts of fly ash, 10 parts of aluminum sulfate, 0.2 part of N-(2-nitrophenyl) ethanolamine and 0.02 part of triisopropoxy titanium chloride complex by mass to obtain Component B.

[0051] Mix 1 part of Component A with 7 parts of water by mass to form a first mixed slurry.

[0052] Mix 1 part of Component B with 7 parts of water by mass to form a second mixed slurry.

[0053] Mix the first mixed slurry and the second mixed slurry by mass to form a coal-based solid waste-based ultra-high water filling material.

[0054] Example 4

[0055] Mix 100 parts of sulfoaluminate clinker, 0.2 part of citric acid and 0.02 part of iron ethylenediaminetetra(methylene phosphonic acid) by mass to obtain Component A.

[0056] Mix 50 parts of desulfurized gypsum, 45 parts of fly ash, 5 parts of aluminum sulfate, 0.1 part of N-(2-nitrophenyl) ethanolamine and 0.05 part of triisopropoxy titanium chloride complex by mass to obtain Component B.

[0057] Mix 1 part of Component A with 7 parts of water by mass to form a first mixed slurry.

[0058] Mix 1 part of Component B with 7 parts of water by mass to form a second mixed slurry.

[0059] Mix the first mixed slurry and the second mixed slurry by mass to form a coal-based solid waste-based ultra-high water filling material.

[0060] Example 5

[0061] Mix 100 parts of sulfoaluminate clinker, 0.2 part of citric acid and 0.01 part of iron ethylenediaminetetra(methylene phosphonic acid) by mass to obtain Component A.

[0062] Mix 50 parts of desulfurized gypsum, 40 parts of fly ash, 10 parts of aluminum sulfate, 0.1 part of N-(2-nitrophenyl) ethanolamine and 0.05 part of triisopropoxy titanium chloride complex by mass to obtain Component B.

[0063] Mix 1 part of Component A with 7 parts of water by mass to form a first mixed slurry.

[0064] Mix 1 part of Component B with 7 parts of water by mass to form a second mixed slurry.

[0065] Mix the first mixed slurry and the second mixed slurry by mass parts to form a coal-based solid waste-based ultra-high water filling material.

[0066] Comparative Example 1

[0067] Mix 100 parts of sulphoaluminate clinker and 0.01 part of iron ethylene diamine tetra (methylene phosphonic acid) by mass parts to obtain component A;

[0068] Mix 40 parts of desulphurized gypsum, 50 parts of fly ash, 10 parts of aluminium sulphate, 0.1 part of N-(2-nitrophenyl) ethanolamine and 0.1 part of triisopropoxy titanium chloride complex by mass parts to obtain component B;

[0069] Mix 1 part of component A with 5 parts of water by mass parts to form the first mixed slurry;

[0070] Mix 1 part of component B with 5 parts of water by mass parts to form the second mixed slurry;

[0071] Mix the first mixed slurry and the second mixed slurry by mass parts to form a coal-based solid waste-based ultra-high water filling material.

[0072] Comparative Example 2

[0073] Mix 100 parts of sulphoaluminate clinker and 0.4 part of citric acid by mass parts to obtain component A;

[0074] Mix 45 parts of desulphurized gypsum, 45 parts of fly ash, 10 parts of aluminium sulphate, 0.2 part of N-(2-nitrophenyl) ethanolamine and 0.02 part of triisopropoxy titanium chloride complex by mass parts to obtain component B;

[0075] Mix 1 part of component A with 7 parts of water by mass parts to form the first mixed slurry;

[0076] Mix 1 part of component B with 7 parts of water by mass parts to form the second mixed slurry;

[0077] Mix the first mixed slurry and the second mixed slurry by mass parts to form a coal-based solid waste-based ultra-high water filling material.

[0078] Comparative Example 3

[0079] Mix 100 parts of sulphoaluminate clinker and 0.2 part of citric acid by mass parts to obtain component A;

[0080] Mix 50 parts of desulphurized gypsum, 40 parts of fly ash, 10 parts of aluminium sulphate and 0.05 part of triisopropoxy titanium chloride complex by mass parts to obtain component B;

[0081] Mix 1 part of component A with 7 parts of water by mass parts to form the first mixed slurry;

[0082] Mix 1 part of component B with 7 parts of water by mass to form a second mixed slurry;

[0083] Mix the first mixed slurry and the second mixed slurry by mass to form a coal-based solid waste-based ultra-high water filling material.

[0084] Comparative Example 4

[0085] Mix 100 parts of sulfoaluminate clinker, 0.2 part of citric acid and 0.02 part of iron ethylenediaminetetra(methylenephosphonic acid) by mass to obtain component A;

[0086] Mix 50 parts of desulfurized gypsum, 45 parts of fly ash, 0.1 part of N-(2-nitrophenyl)ethanolamine and 0.05 part of triisopropoxytitanium chloride complex by mass to obtain component B;

[0087] Mix 1 part of component A with 7 parts of water by mass to form a first mixed slurry;

[0088] Mix 1 part of component B with 7 parts of water by mass to form a second mixed slurry;

[0089] Mix the first mixed slurry and the second mixed slurry by mass to form a coal-based solid waste-based ultra-high water filling material.

[0090] Comparative Example 5

[0091] Mix 100 parts of sulfoaluminate clinker, 0.2 part of citric acid and 0.02 part of iron ethylenediaminetetra(methylenephosphonic acid) by mass to obtain component A;

[0092] Mix 50 parts of desulfurized gypsum, 40 parts of fly ash, 10 parts of aluminum sulfate and 0.1 part of N-(2-nitrophenyl)ethanolamine by mass to obtain component B;

[0093] Mix 1 part of component A with 7 parts of water by mass to form a first mixed slurry;

[0094] Mix 1 part of component B with 7 parts of water by mass to form a second mixed slurry;

[0095] Mix the first mixed slurry and the second mixed slurry by mass to form a coal-based solid waste-based ultra-high water filling material.

[0096] The components of the coal-based solid waste-based ultra-high water filling material, as well as the test results of the setting time and compressive strength, are described in the following table, specifically as shown in Table 1:

[0097] Table 1

[0098]

[0099]

[0100] As can be seen from Example 1 and Comparative Example 1, citric acid plays a retarding role. If citric acid is not added to the system, the setting time of the slurry will be too short, which is not conducive to grouting.

[0101] As can be seen from Example 3 and Comparative Example 2, iron ethylenediaminetetra(methylene phosphonic acid) can increase the strength by 32%.

[0102] As can be seen from Example 5 and Comparative Example 3, adding iron ethylenediaminetetra(methylene phosphonic acid) and N-(2-nitrophenyl)ethanolamine simultaneously can not only make the setting time reach a more reasonable range, but also increase the strength by 67%.

[0103] As can be seen from Example 4 and Comparative Example 4, aluminum sulfate can optimize the setting time of the slurry and increase the compressive strength.

[0104] As can be seen from Example 5 and Comparative Example 5, titanium isopropoxide chloride complex can promote the synergistic reaction of iron ethylenediaminetetra(methylene phosphonic acid) and N-(2-nitrophenyl)ethanolamine, increase the mine pressure strength of the system and shorten the setting time of the system.

[0105] In summary, a coal-based solid waste-based ultra-high water filling material and its preparation method provided by the present invention can improve the utilization rate of coal-based solid waste, reduce the material cost, while improving the stability and strength of the material and enhancing the environmental adaptability.

[0106] It is easy for those skilled in the art to understand that, on the premise of no conflict, the above advantageous ways can be freely combined and superimposed. The above are only the preferred embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above is only the preferred implementation manner of the present application. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present application, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A coal-based solid waste-based ultra-high water filling material, characterized in that: The filling material consists of component A and component B, wherein the component A includes the following components: sulphoaluminate clinker, citric acid and ethylenediaminetetra(methylenephosphonic acid) iron; the component B includes the following components: desulfurized gypsum, fly ash, aluminum sulfate, N-(2-nitrophenyl)ethanolamine and triisopropoxytitanium chloride complex.

2. The filling material according to claim 1, characterized in that: The components in the component A include, by weight: 100 parts of sulphoaluminate clinker, 0.2-0.4 parts of citric acid, and 0.01-0.02 parts of ethylenediaminetetramethylenephosphonic acid iron.

3. The filling material according to claim 1, characterized in that: The components in the second component include, by mass, 40-60 parts of desulfurized gypsum, 35-50 parts of fly ash, 5-10 parts of aluminum sulfate, 0.1-2 parts of N-(2-nitrophenyl)ethanolamine and 0.02-0.1 parts of triisopropoxy titanium chloride complex.

4. The method for preparing the coal-based solid waste-based ultra-high water filling material according to any one of claims 1 to 3, characterized in that: include: Mixing component A with water to form a first mixed slurry; Mixing component B with water to form a second mixed slurry; The first mixed slurry and the second mixed slurry are mixed to form a coal-based solid waste-based ultra-high water filling material.

5. The method according to claim 4, characterized in that Component A is mixed with water in a mass ratio of 1:(5-7) to form a first mixed slurry.

6. The method according to claim 4, characterized in that The second mixed slurry is formed by mixing component B with water in a mass ratio of 1:(5-7).

7. The method according to claim 4, characterized in that The first mixed slurry and the second mixed slurry are mixed in a mass ratio of 1:(0.5-2) to form a coal-based solid waste-based ultra-high water filling material.

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