Mine filling material based on high-salinity brine mine water and preparation method thereof

Abstract

The present invention relates to the technical field of mine filling materials, and discloses a mine filling material based on high-salt brine mine water and a preparation method thereof, wherein the mine filling material of the present invention comprises 21-42 parts by weight of high-salt brine mine water, 50-61 parts by weight of chlorine-containing tailings, 5-18 parts by weight of pre-excited gelling slurry, and 3-8 parts by weight of cardanol-based polyurethane binder emulsion; after the water-quenched blast furnace slag powder is surface-modified with oleic acid, long-chain alkanes are introduced on the surface, and its dispersibility becomes better, and calcium salt is used as an exciter, which has a better excitation and activation effect on the slag powder, and is conducive to improving the mechanical properties of the solidified filling material. The side chain of the polyurethane binder emulsion also contains long-chain alkanes, which have a physical chain entanglement effect with the long-chain alkanes on the surface of the slag powder, thereby improving the interfacial bonding force between the slag powder and the polyurethane binder, and significantly improving the compressive strength and mechanical properties of the filling material.

Description

Technical Field

[0001] The invention relates to the technical field of mine filling materials, in particular to a mine filling material based on high-salinity brine mine water and a preparation method thereof. Background Art

[0002] For underground mines in arid, semi-arid and coastal saline-alkali areas, high-salinity brine mine water is lifted to the surface during the mining process, and surface discharge is very likely to cause surface salinization, surface water pollution and other problems. At present, the desalination and disposal technology of high-salinity brine mine water is complex and costly. Mines usually use it as water for mineral processing and underground filling, which can save a lot of fresh water resources in saline-alkali areas where fresh water is already scarce. In addition, the surface of tailings produced by mines has chloride components attached to it, which makes it difficult to realize resource utilization such as making building materials. The conventional disposal method is to mix tailings with cementitious materials and mix them with mine water to make filling materials and fill them into the underground goaf to form a filling body with a certain strength, which provides safety for mining. However, for underground mines in arid, semi-arid and coastal saline-alkali areas, compared with ordinary freshwater mine water, high-salinity brine mine water is rich in a large number of chloride anions and alkali cations such as sodium, calcium and magnesium. The proper use of certain alkali cations is conducive to the production of cementitious components and the improvement of the early strength of the filling body.

[0003] Polyurethane is a high-performance polymer material, which is widely used in grouting materials, mine reinforcement and other aspects. The Chinese patent application with publication number CN117658533A discloses a solid waste-based polyurethane composite grouting material suitable for water-rich sand layer water blocking and reinforcement management and its preparation method. The solid waste-based polyurethane composite grouting material prepared with fly ash, blast furnace slag, cement, polyisocyanate, polyether polyol, diluent, water glass and retarder as raw materials can achieve the dual purpose of efficient treatment of water-rich sand layer grouting water blocking reinforcement and resource utilization of solid waste materials. However, the compressive strength of the polyurethane composite grouting material is low, which is difficult to meet the practical application of grouting materials in ore filling and other aspects. Improving the compatibility and interface bonding performance between blast furnace slag and polyurethane can further improve the mechanical properties of grouting materials. Summary of the invention

[0004] In order to realize the large-scale filling of underground goafs with high-salinity brine mine water and chlorine-containing tailings in underground mines to avoid surface discharge and ensure the safety of mine production, the present invention provides a mine filling material based on high-salinity brine mine water and a preparation method, which realizes the resource utilization of two types of difficult-to-dispose mine wastes, chlorine-salinity mine water and chlorine-containing tailings, treats underground goafs and avoids surface water and soil pollution, and has important safety, economic and environmental benefits.

[0005] In order to achieve the above purpose, the present invention specifically adopts the following technical solutions:

[0006] A mine filling material based on high-salinity brine mine water, comprising 21-42 parts by weight of high-salinity brine mine water, 50-61 parts by weight of chlorine-containing tailings, 5-18 parts by weight of pre-excited gelling slurry, and 3-8 parts by weight of cardanol-based polyurethane binder emulsion;

[0007] The pre-activated gelling slurry is composed of 17-30% by weight of high-salt brine mine water, 60-67% by weight of modified water-quenched blast furnace slag powder, and 10-16% by weight of a calcium salt activator;

[0008] The preparation method of the modified water-quenched blast furnace slag powder is as follows: 100 parts by weight of water-quenched blast furnace slag powder, ethanol, and 2-5 parts by weight of oleic acid are added into water, heated to 70-85° C., stirred for modification for 1-2 hours, condensed and refluxed during stirring, filtered, washed with ethanol, and dried to obtain the modified water-quenched blast furnace slag powder.

[0009] Preferably, the mineralized chloride content in the high-salinity brine mine water is 50-80 g / L, and the chloride salts include sodium chloride, magnesium chloride, and calcium chloride.

[0010] Preferably, the proportion of particle size ≦20 μm in the chlorine-containing tailings is 30-65%.

[0011] Preferably, the specific surface area of ​​the calcium salt activator is 400-500 m 2 / kg, the calcium salt activator is a solid powder mixture composed of calcium chloride and calcium sulfate in a mass ratio of 1:1.6-2.

[0012] Preferably, the specific surface area of ​​the water-quenched blast furnace slag powder is 350-600 m 2 / kg.

[0013] Preferably, the preparation method of the cardanol-based polyurethane binder emulsion is: heat 100 parts by weight of polyether polyol 2000 to 110-120°C, vacuum dehydrate for 2-3 hours, reduce the temperature to 70-80°C, add 21-30 parts by weight of isocyanate monomer and 11-14 parts by weight of 2,2-dimethylolpropionic acid, react in a nitrogen atmosphere for 2.5-3 hours, then add acetone and 15-21 parts by weight of cardanol diol, react at 40-50°C for 30-50 minutes, add triethylamine for neutralization, add water, stir and disperse to obtain the cardanol-based polyurethane binder emulsion.

[0014] Preferably, the polyether polyol is polytetramethylene glycol or polyethylene glycol, and the isocyanate monomer is toluene diisocyanate or diphenylmethane diisocyanate.

[0015] A method for preparing a mine filling material based on high-brine mine water: adding modified water-quenched blast furnace slag powder and a calcium salt activator to the high-brine mine water, stirring and mixing, to obtain a pre-activated gelling slurry; then adding the high-brine mine water, chlorine-containing tailings, and a cardanol-based polyurethane binder emulsion, stirring and mixing, to obtain a mine filling material based on the high-brine mine water.

[0016] Beneficial effects: The present invention uses modified water-quenched blast furnace slag powder, calcium salt activator, and high-salt brine mine water as raw materials for pre-stimulated gelling slurry, and is mixed and solidified with chlorine-containing tailings, cardanol-based polyurethane binder emulsion, etc. to obtain a mine filling material. After the water-quenched blast furnace slag powder is surface-modified with oleic acid, long-chain alkanes are introduced on the surface, and its dispersibility becomes better. At the same time, calcium salt is used as an activator, which has a better excitation and activation effect on the slag powder, which is beneficial to improve the compressive strength and mechanical properties of the solidified filling material.

[0017] The present invention uses cardanol diol as a chain extender, and the side chain of the prepared polyurethane binder emulsion also contains long-chain alkanes, which undergo physical chain entanglement with the long-chain alkanes on the surface of slag powder, thereby improving the interfacial bonding force between the slag powder and the polyurethane binder and significantly improving the compressive strength and mechanical properties of the filling material.

[0018] The present invention realizes resource utilization of chlorine-salt mine water and chlorine-containing tailings, which are difficult-to-dispose wastes in mines, treats underground goaf areas and avoids surface water and soil pollution, and has important safety, economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a scanning electron microscope image of the mine filling material prepared by the present invention after solidification. DETAILED DESCRIPTION

[0020] The following high-salinity brine mine water has a mineralized chloride content of about 61.8 g / L. Chloride salts include sodium chloride, magnesium chloride, and calcium chloride, which are produced from the Sanshan Island gold mine on the Jiaodong Peninsula near Laizhou Bay. The proportion of chlorine-containing tailings with a particle size of ≤20 μm is 44.3%, which is produced from the Sanshan Island gold mine on the Jiaodong Peninsula near Laizhou Bay. The specific surface area of ​​water-quenched blast furnace slag powder is 523.6 m 2 / kg, produced by Gongyi Longze Water Purification Material Co., Ltd. The specific surface area of ​​the calcium salt activator is 469.5 m 2 / kg, is a solid powder mixture consisting of calcium chloride and calcium sulfate in a mass ratio of about 1:1.87.

[0021] The structural formula of cardanol diol is , n is 0-3.

[0022] Example 1: Preparation method of mine filling material based on high-salinity brine mine water:

[0023] (1) 200 g of polyethylene glycol 2000 was heated to 110°C and vacuum dehydrated for 3 h. The temperature was lowered to 75°C, 42 g of toluene diisocyanate and 24.7 g of 2,2-dimethylol propionic acid were added, and the mixture was reacted in a nitrogen atmosphere for 3 h. Then, 50 mL of acetone and 37.5 g of cardanol diol were added, and the mixture was reacted at 50°C for 30 min. Triethylamine was added for neutralization, and 350 mL of water was added and the mixture was stirred and dispersed to obtain a cardanol-based polyurethane binder emulsion.

[0024] (2) Add 1 kg of water-quenched blast furnace slag powder, 500 mL of ethanol, and 35 g of oleic acid to 5 L of water, heat to 85 ° C, stir and modify for 1 hour, condense and reflux during stirring, filter, wash with ethanol, and dry to obtain modified water-quenched blast furnace slag powder;

[0025] (3) adding 6.4 kg of modified water-quenched blast furnace slag powder and 1.2 kg of calcium salt activator to 2.4 kg of high-salinity brine mine water, stirring and mixing to obtain a pre-activated gelling slurry;

[0026] (4) Add 21 kg of high-salinity brine mine water, 60 kg of chlorine-containing tailings, and 4 kg of cardanol-based polyurethane binder emulsion to 15 kg of pre-stimulated cementitious slurry, stir and mix, and obtain a mine filling material based on high-salinity brine mine water.

[0027] Comparative Example 1: The difference between this comparative example and Example 1 is that unmodified water-quenched blast furnace slag powder is added.

[0028] (1) Add 6.4 kg of water-quenched blast furnace slag powder and 1.2 kg of calcium salt activator into 2.4 kg of high-salinity brine mine water, stir and mix to obtain a pre-activated gelling slurry;

[0029] (2) Add 28 kg of high-salinity mine water, 60 kg of chlorine-containing tailings, and 4 kg of cardanol-based polyurethane binder emulsion (prepared in the same way as in Example 1) to 8 kg of pre-excited gelling slurry, and stir to obtain a mine filling material based on high-salinity mine water.

[0030] Comparative Example 2: The difference between this comparative example and Example 1 is that 1,4-butanediol is used instead of cardanol diol as the chain extender of the polyurethane binder.

[0031] (1) Heat 200g of polyethylene glycol 2000 to 110°C, vacuum dehydrate for 3h, reduce the temperature to 75°C, add 42g of toluene diisocyanate and 24.7g of 2,2-dihydroxymethyl propionic acid, react in a nitrogen atmosphere for 3h, then add 50mL of acetone and 9g of 1,4-butanediol, react at 50°C for 30min, add triethylamine for neutralization, add 350mL of water, stir and disperse, and obtain a polyurethane binder emulsion;

[0032] (2) adding 6.4 kg of modified water-quenched blast furnace slag powder (prepared in the same manner as in Example 1) and 1.2 kg of calcium salt activator to 2.4 kg of high-salinity brine mine water, stirring and mixing to obtain a pre-activated gelling slurry;

[0033] (3) Add 21 kg of high-salinity brine mine water, 60 kg of chlorine-containing tailings, and 4 kg of polyurethane binder emulsion to 15 kg of pre-stimulated cementitious slurry, stir and mix, and obtain a mine filling material based on high-salinity brine mine water.

[0034] Comparative Example 3: The difference between this comparative example and Example 1 is that sodium hydroxide is used as the activator instead of the calcium salt activator.

[0035] (1) Add 6.4 kg of modified water-quenched blast furnace slag powder and 1.2 kg of sodium hydroxide activator into 2.4 kg of high-salinity brine mine water, stir and mix to obtain a pre-activated gelling slurry;

[0036] (2) Add 21 kg of high-salinity brine mine water, 60 kg of chlorine-containing tailings, and 4 kg of cardanol-based polyurethane binder emulsion to 15 kg of pre-stimulated gelling slurry, stir and mix, and obtain a mine filling material based on high-salinity brine mine water.

[0037] Comparative Example 4: The difference between this comparative example and Example 1 is that sodium silicate is used as the activator instead of the calcium salt activator.

[0038] (1) Add 6.4 kg of modified water-quenched blast furnace slag powder and 1.2 kg of sodium silicate activator into 2.4 kg of high-salinity brine mine water, stir and mix to obtain a pre-activated gelling slurry;

[0039] (2) Add 21 kg of high-salinity brine mine water, 60 kg of chlorine-containing tailings, and 4 kg of cardanol-based polyurethane binder emulsion to 15 kg of pre-stimulated gelling slurry, stir and mix, and obtain a mine filling material based on high-salinity brine mine water.

[0040] Example 2: Preparation method of mine filling material based on high-salinity brine mine water:

[0041] (1) 200 g of polytetramethylene glycol 2000 was heated to 110°C, vacuum dehydrated for 3 h, the temperature was lowered to 80°C, 44 g of toluene diisocyanate and 28 g of 2,2-dimethylol propionic acid were added, and the mixture was reacted in a nitrogen atmosphere for 2.5 h. Then, 50 mL of acetone and 30 g of cardanol diol were added, and the mixture was reacted at 40°C for 50 min. Triethylamine was added for neutralization, and 350 mL of water was added, and the mixture was stirred and dispersed to obtain a cardanol-based polyurethane binder emulsion.

[0042] (2) Add 1 kg of water-quenched blast furnace slag powder, 800 mL of ethanol, and 50 g of oleic acid to 6 L of water, heat to 85 ° C, stir and modify for 1 hour, condense and reflux during stirring, filter, wash with ethanol, and dry to obtain modified water-quenched blast furnace slag powder;

[0043] (3) Add 6 kg of modified water-quenched blast furnace slag powder and 1 kg of calcium salt activator into 3 kg of high-salinity brine mine water, stir and mix to obtain a pre-activated gelling slurry;

[0044] (4) Add 21 kg of high-salinity brine mine water, 56 kg of chlorine-containing tailings, and 8 kg of cardanol-based polyurethane binder emulsion to 15 kg of pre-stimulated cementitious slurry, stir and mix, and obtain a mine filling material based on high-salinity brine mine water.

[0045] Example 3: Preparation method of mine filling material based on high-salinity brine mine water:

[0046] (1) 200 g of polyethylene glycol 2000 was heated to 110°C, vacuum dehydrated for 3 h, the temperature was lowered to 70°C, 60 g of diphenylmethane diisocyanate and 22 g of 2,2-dihydroxymethylpropionic acid were added, and the mixture was reacted in a nitrogen atmosphere for 3 h. Then 80 mL of acetone and 42 g of cardanol diol were added, and the mixture was reacted at 40°C for 50 min. Triethylamine was added for neutralization, and 300 mL of water was added, and the mixture was stirred and dispersed to obtain a cardanol-based polyurethane binder emulsion;

[0047] (2) Add 1 kg of water-quenched blast furnace slag powder, 300 mL of ethanol, and 20 g of oleic acid to 5 L of water, heat to 70 ° C, stir and modify for 2 hours, condense and reflux during stirring, filter, wash with ethanol, and dry to obtain modified water-quenched blast furnace slag powder;

[0048] (3) adding 6.7 kg of modified water-quenched blast furnace slag powder and 1.6 kg of calcium salt activator to 1.7 kg of high-salinity brine mine water, stirring and mixing to obtain a pre-activated gelling slurry;

[0049] (4) Add 21 kg of high-salinity brine mine water, 61 kg of chlorine-containing tailings, and 6 kg of cardanol-based polyurethane binder emulsion to 12 kg of pre-stimulated gelling slurry, stir and mix, and obtain a mine filling material based on high-salinity brine mine water.

[0050] Example 4: Preparation method of mine filling material based on high-salinity brine mine water:

[0051] (1) 6.4 kg of modified water-quenched blast furnace slag powder (prepared in the same manner as in Example 1) and 1.4 kg of calcium salt activator were added to 2.2 kg of high-salinity brine mine water, and stirred to obtain a pre-activated gelling slurry;

[0052] (2) Add 42 kg of high-salinity mine water, 50 kg of chlorine-containing tailings, and 3 kg of cardanol-based polyurethane binder emulsion (prepared in the same way as in Example 1) to 5 kg of pre-excited gelling slurry, stir and mix, and obtain a mine filling material based on high-salinity mine water.

[0053] Example 5: Preparation method of mine filling material based on high-salinity brine mine water:

[0054] (1) 6.7 kg of modified water-quenched blast furnace slag powder (prepared in the same manner as in Example 1) and 1.4 kg of calcium salt activator were added to 1.9 kg of high-salinity brine mine water, and the mixture was stirred to obtain a pre-activated gelling slurry;

[0055] (2) Add 21 kg of high-salinity mine water, 56 kg of chlorine-containing tailings, and 5 kg of cardanol-based polyurethane binder emulsion (prepared in the same way as in Example 1) to 18 kg of pre-excited gelling slurry, and stir to obtain a mine filling material based on high-salinity mine water.

[0056] The mine filling material is poured into the mold, vibrated to degas, and cured at room temperature for 3-28 days to make a sample. The compressive strength is tested according to the GB / T17671-2021 method, as shown in Table 1 below.

[0057] Table 1: Compressive strength test results of various embodiments and comparative examples

[0058]

[0059] After testing, the mine filling material of Example 1 has a compressive strength of 4.3-15.3MPa after solidification and 3-28 days of curing. This is mainly because after the water-quenched blast furnace slag powder is surface-modified with oleic acid, long-chain alkanes are introduced on the surface, and its dispersibility becomes better, which is conducive to improving the compressive strength and mechanical properties of the solidified filling material. At the same time, the side chain of the prepared polyurethane binder emulsion using cardanol diol as a chain extender also contains long-chain alkanes, which physically entangle with the long-chain alkanes on the surface of the slag powder, thereby improving the interfacial bonding force between the slag powder and the polyurethane binder, and can further improve the compressive strength. At the same time, compared with traditional sodium hydroxide and sodium silicate activators, calcium salt as an activator has a better excitation and activation effect on slag powder, so that the compressive strength of Example 1 is higher than that of Comparative Examples 3 and 4.

[0060] The water-quenched blast furnace slag powder in Comparative Example 1 has not undergone oleic acid surface modification, has poor dispersibility, and cannot undergo physical chain entanglement with the long-chain alkanes of the polyurethane binder. The interfacial bonding force between the two is weak, and the reinforcing effect of the slag powder is low, resulting in a compressive strength lower than that of Example 1.

[0061] In Comparative Example 2, conventional 1,4-butanediol is used as a chain extender. The resulting polyurethane binder does not contain long-chain alkanes and cannot undergo physical chain entanglement with the long-chain alkanes on the surface of the slag powder. The interfacial bonding force between the two is weak, resulting in a compressive strength lower than that of Example 1.

[0062] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A mine filling material based on high-salinity brine mine water, characterized in that: It comprises 21-42 parts by weight of high-salinity brine mine water, 50-61 parts by weight of chlorine-containing tailings, 5-18 parts by weight of pre-excited gelling slurry, and 3-8 parts by weight of cardanol-based polyurethane binder emulsion; The pre-activated gelling slurry is composed of 17-30% by weight of high-salt brine mine water, 60-67% by weight of modified water-quenched blast furnace slag powder, and 10-16% by weight of a calcium salt activator; The preparation method of the modified water-quenched blast furnace slag powder is as follows: adding water-quenched blast furnace slag powder, ethanol and oleic acid into water, stirring for modification, filtering, washing and drying to obtain the modified water-quenched blast furnace slag powder.

2. The mine filling material based on high-salinity brine mine water according to claim 1, characterized in that: The mineralized chloride content in the high-salinity brine mine water is 50-80 g / L, and the chloride salts include sodium chloride, magnesium chloride, and calcium chloride.

3. The mine filling material based on high-salinity brine mine water according to claim 1, characterized in that: The proportion of particles with a diameter of ≤20 μm in the chlorine-containing tailings is 30-65%.

4. The mine filling material based on high-salinity brine mine water according to claim 1, characterized in that: In the preparation method of the modified water-quenched blast furnace slag powder, the amount of the water-quenched blast furnace slag powder is 100 parts by weight and the amount of oleic acid is 2-5 parts by weight.

5. The mine filling material based on high-salinity brine mine water according to claim 1, characterized in that: In the preparation method of the modified water-quenched blast furnace slag powder, the modification temperature is 70-85° C. and the modification time is 1-2 hours.

6. The mine filling material based on high-salinity brine mine water according to claim 1, characterized in that: The specific surface area of ​​the calcium salt activator is 400-500 m 2 / kg, the calcium salt activator is a solid powder mixture composed of calcium chloride and calcium sulfate in a mass ratio of 1:1.6-2.

7. The mine filling material based on high-salinity brine mine water according to claim 1, characterized in that: The specific surface area of ​​the water-quenched blast furnace slag powder is 350-600 m 2 / kg.

8. The mine filling material based on high-salinity brine mine water according to claim 1, characterized in that: The preparation method of the cardanol-based polyurethane binder emulsion is as follows: 100 parts by weight of polyether polyol is heated to 110-120° C., vacuum dehydrated for 2-3 hours, the temperature is reduced to 70-80° C., 21-30 parts by weight of isocyanate monomer and 11-14 parts by weight of 2,2-dimethylolpropionic acid are added, reacted in a nitrogen atmosphere for 2.5-3 hours, acetone and 15-21 parts by weight of cardanol diol are added, reacted at 40-50° C. for 30-50 minutes, triethylamine is added for neutralization, water is added, and the mixture is stirred and dispersed to obtain the cardanol-based polyurethane binder emulsion.

9. The mine filling material based on high-salinity brine mine water according to claim 8, characterized in that: The polyether polyol is polytetramethylene glycol or polyethylene glycol, and the isocyanate monomer is toluene diisocyanate or diphenylmethane diisocyanate.

10. The method for preparing a mine filling material based on high-salinity brine mine water according to any one of claims 1 to 9, characterized in that: The preparation method comprises the following steps: adding modified water-quenched blast furnace slag powder and a calcium salt activator to high-brine mine water, stirring and mixing, and obtaining a pre-activated gelling slurry; and then adding high-brine mine water, chlorine-containing tailings, and a cardanol-based polyurethane binder emulsion, stirring and mixing, and obtaining a mine filling material based on high-brine mine water.

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