Liquid inorganic material for crack reinforcement and preparation method therefor

Abstract

l 3 Disclosed in the present invention are a liquid inorganic material for crack reinforcement and a preparation method therefor. The liquid inorganic material includes component A liquid and component B liquid, where a mass ratio of the component A liquid to the component B liquid is (2—4): 1; the component A liquid includes in parts by mass: 75—90 parts of an adhesive, 30-50 parts of diatomite, and 1-5 parts of a stabilizer, and after mixing, a pH value of the component A liquid is 7—9; and the component B liquid includes in parts by mass: 10—20 parts of waste phosphoric acid, 50-150 parts of water, and 30-100 parts of inorganic salts, and after mixing, a pH value of the component B liquid is 1—1.5. Additionally, according to the size of cracks and the total quantity of injected materials, appropriate quantities of the ultrafine steel fibers are added to improve the strength after solidification.

Description

l LIQUID INORGANICMATERIALFORCRACKREINFORCEMENTAND PREPARATIONMETHODTHEREFOR TECHNICAL FIELD

[0001] The present invention relates to a material for crack reinforcement and a preparation method therefor, in particular to a liquid inorganic material for crack reinforcement and a preparation method therefor, and belongs to the technical eld ofcoal mine reinforcement. BACKGROUND

[0002] Coal is important fossil fuel widely used in power generation, industrial production, household heating, and the like. In China, production from underground mining accounts for 95% of the total production. Fractured geological conditions have a signicant impact on underground coal mining. The fractured geology leads to a loose structure of an ore body, which is easy to affect by external force to deform or collapse, causing certain difculties in underground coal mining. Therefore, corresponding technical measures need to be taken for support and reinforcement. In the hydrogeological environment, loose and fragmented geological conditions result in high porosity and permeability of the rock layers, thereby making it easy for groundwater to infiltrate, and increasing the risk ofmine permeability. This may also result in high humidity inside the mine, which has adverse effects on underground workers. Additionally, the loose geology will also increase permeability of coal seams, allowing fresh air to enter the coal seams through fractures and pores during ventilation. The development of jointing fractures provides an adherent environment for oxygen, further promoting an oxidation reaction of coal bodies and increasing the risk of spontaneous combustion. Thus, effective measures for gas extraction and management are needed. Furthermore, the loose geology makes the coal seams less stable, leading to an increased difculty in mining. To ensure production safety, more cautious and complex mining processes and technologies need to be adopted.

[0003] From the above situation, it can be concluded that it is necessary to take reinforcement measures for loose and fractured geological conditions in the mining course. The main materials currently used are modied cement and resin materials. Herein, modied cement reinforcement materials have limited durability, and need to be stirred in a certain proportion on site foruse before grouting, which reduces the efciency ofgrouting. Although the resin materials have high strength after solidication, they are high in viscosity and difcult to grout. Moreover, the resin materials are high in solidication reaction temperature and poor in ame retardancy after injection. Therefore, the resin materials are only suitable for coal seams with low risk of spontaneous combustion of coal and low gas occurrence, making their use conditions harsh.

[0004] In summary, it is one ofresearch directions in this industry to provide anew material for crack reinforcement and a preparation method therefor, that has high strength after solidication, has controllable gelation time, low solidication reaction temperature, and strong bonding force, thereby having good durability, and has good injection efciency. SUMMARY

[0005] In response to the problems existing in the prior art mentioned above, the present invention provides a liquid inorganic material for crack reinforcement and a preparation method therefor. The liquid inorganic material has high strength after solidication, has controllable gelation time, low solidication reaction temperature, and strong bonding force, thereby having good durability; and furthermore, the liquid inorganic material does not need to be prepared on site, thereby having good injection efciency.

[0006] In order to achieve the above objectives, the present invention adopts the technical solution that the liquid inorganic material for crack reinforcement includes componentA liquidandcomponentB liquid,where amass ratio ofthe componentAliquid to the component B liquid is (24):l;

[0007] the componentA liquid specically includes in parts by mass: 75-90 parts of an adhesive, 30-50 parts ofdiatomite, and 1-5 parts ofa stabilizer, and after mixing, apH value ofthe componentA liquid is 7-9; and

[0008] the component B liquid specically includes in parts by mass: 10-20 parts ofwaste phosphoric acid, 50-150 parts ofwater, and 30-100 parts ofinorganic salts, and after mixing, apH value ofthe componentB liquid is 1-1.5.

[0009] Further, the liquid inorganic material further includes a component C which is ultrane steel bers. When small cracks are sealed and reinforced, the componentA liquid and the componentB liquid aremixed to be injected into an areawhich needs to be reinforced, and then the small cracks can be sealed and reinforced after the injected componentA liquid and the injected componentB liquid are cured; when large cracks are sealed and reinforced, according to the actual situation of the cracks, appropriate quantities ofultrane steel bers are added to the componentA liquid, the ultrane steel bers and the componentA liquid are stirred and mixed uniformly to obtainnew componentA liquid, and then, the new component liquid and the component B liquid are mixed and injected into an area which needs to be reinforced. After the injectednewcomponent liquid and the injected componentB liquid were cured, the ultrane steel bers can effectively improve the strength after solidication, thereby ensuring the sealing and reinforcement effect on the large cracks. Specic addition criteria are: ___

[0010] Note: the ultrane corrugated steel bers are added until both themaximum width of the fractures andthe totalusage quantity ofthe materials reachparameters. Before theultrane corrugated steel bers are added, the materials which are 30% of the total usage quantity shouldbe injected into the cracks, and the ultrane corrugated steel bers should be added to the remaining70% ofthe injected materials; and the usage quantity ofthe ultrane corrugated steel bers is determined according to the percentage of the total usage quantity of the materials.

[0011] Further, the adhesive is propenoic acid emulsion.

[0012] Further, the particle size of the diatomite is 100150 meshes. By using the particle size, it can be ensured that the diatomite is more uniformly dispersed in the componentA liquid, thereby improving the strength ofthe materials after solidication.

[0013] Further, a pH value of the waste phosphoric acid should be smaller than 1. By selecting the pH value, it is necessary to ensure that the component B liquid subsequently prepared meets the requirements for the requiredpH value.

[0014] Further, the stabilizer is one or amixture ofsodium-basedbentonite orcalcium-based bentonite.

[0015] Further, the inorganic salts are one or a mixture of sodium chloride, magnesium chloride, and calcium chloride.

[0016] Further, the ultrane steel bers consist ofone or a mixture of stainless steel bers, aluminum alloy steel bers, and silicon steel bers. The ultrane steel bers can be prepared from any of the above materials, or some ultrane steel bers can be prepared from each material separately, and then the ultrane steel bers prepared from various materials can be mixed for standby application. Ifconditions permit, amanner that the ultrane steel bers are prepared from various materials is preferred, because the ultrane steel bers prepared from differentmaterials have theirown characteristics inrespectiveperformance. After the ultrane steel bers are injected into the cracks to be solidied, better results can be achieved.

[0017] The preparation method for the liquid inorganic material for crack reinforcement includes the specic steps:

[0018] (1) preparationofthe componentA liquid: atroomtemperature (namely, 20°C-25°C), adding the stabilizer and the diatomite into the propenoic acid emulsion according to a required ratio, performing stirring at a speed of600 r / min, afterperforming stirring for 2 min, preparing the componentA liquid, loading the componentA liquid in barrels for standby application, and enabling thepH value ofthe componentA liquid to be 7-9; and

[0019] (2) preparation ofthe componentB liquid: atroom temperature (namely, 20°C25°C), adding water to the waste phosphoric acid according to a required ratio, performing stirring at a speed of600 r / min for 2 min, then adding the inorganic salts, performing stirring until the inorganic salts are completely dissolved to prepare the component B liquid, loading the component B liquid in barrels for standby application, and enabling the pH value of the componentB liquid to be 1-1.5.

[0020] The stabilizer in the componentA of the present invention can improve suspension stability, cohesiveness, consistency and dispersibility of the propenoic acid emulsion; the diatomite can increase the hardness of the propenoic acid emulsion and make the material have higher strength; the inorganic salts can disperse ionic components in the component A, making the material have higher stability and strength after solidication; and by adjusting a ratio ofwater to the waste phosphoric acid, the coagulation speed of the inorganic material can be controlled. Compared with the prior art, the present invention has the following advantages:

[0021] (1) having high strength: the diatomite contains 50% or above of SiOz and 15-30% ofA1203, which are insoluble in the emulsion, and the Mohs hardness of the A1203 and the Si02 is more than 7. Due to the dispersibility and the suspension stability ofthe stabilizer, the stabilizer can be uniformly dispersed in the emulsion, does not precipitate, and can also be uniformly dispersed in the material after solidication, therebymaking the material have high strength. In addition, adding the componentC as needed can signicantly improve the strength ofthe material, the ultrane steel bers increase a contact area, such that the ultrane steel bers can be better bonded to the material, thereby improving the hardness ofthe material.

[0022] (2) Preventing fracture growth: due to existence anduniform distribution ofSi02 and A1203 particles in the diatomite, besides, the stabilizer can increase the cohesiveness of the propenoic acid emulsion, such that the cracks can be fully bonded, and high-hardness Si02 andA1203 can play a role in blocking fracture growth.

[0023] (3) Low reaction temperature: during the preparation of the componentA and the component B, a large amount ofheat has already been released, causing the two to release a small amount of heat in the subsequent course of mixing, injection into the cracks and solidication, resulting in a maximum temperature change of no more than 4.5 °C on the material surface, reducing the possibility ofgas accidents.

[0024] (4) Strong cohesiveness: the componentA and the component B are liquid, and the viscosity of the componentA reaches 300 mPa-s, such that fracture surfaces can be better inltrated. The stabilizer improves the cohesiveness ofthe propenoic acid emulsion, making the material more integrated with the surrounding environment after solidication.

[0025] (5) Wide applicability: for small cracks, the componentA and the component B can be directly used to achieve the required reinforcement strength. For larger cracks, appropriate quantities ofthe component C can be added to enhance internal tensile strength and strength, making the material suitable for sealing and reinforcing cracks ofdifferent sizes. In addition, the reinforcement material is not only suitable for crack reinforcement in mines, but also for crack reinforcement in industries such as construction, roads, and bridges.

[0026] (6) Waste utilization: the present invention uses industrial discarded waste phosphoric acid as a raw material, reducing waste emissions and pollution, effectively realizing waste reuse, not only saving costs, but also having better environmental protection effects. BRIEF DESCRIPTION OF THEDRAWINGS

[0027] FIG. 1 is a owchart ofa preparation and use course ofthe present invention;

[0028] FIG. 2 is a microscopic comparison diagram for fracture growth of the present invention with addition ofdiatomite and that without addition ofthe diatomite;

[0029] (a) the microscopic diagram with the addition of the diatomite, (b) the microscopic diagram without the addition ofthe diatomite; and

[0030] FIG. 3 is an internal schematic diagram when ultrane steel bers are added for reinforcement oflarge cracks in the present invention.

[0031] In the gures: 1. A1203 molecule; 2. Si02 molecule; 3. crack; 4. material for crack reinforcement; 5. ultrane steel ber. DETAILED DESCRIPTIONOF THEEMBODIMENTS

[0032] The present invention is further described below.

[0033] Example 1:A liquid inorganic material includes componentA liquid andcomponent B liquid, where the componentA liquid includes in parts by mass: 80 parts ofpropenoic acid emulsion, 45 parts of diatomite and 2 parts of a stabilizer which is sodium-based bentonite; and the component B liquid specically includes in parts by mass: 12 parts of waste phosphoric acid, 50 parts ofwater, and 32 parts ofinorganic salts which are sodium chloride.

[0034] Specic preparation steps are:

[0035] (1) preparationofthe componentA liquid: atroomtemperature (namely, 20°C-25°C), the stabilizer and the diatomite were added into the propenoic acid emulsion according to a required ratio, stirringwas performed at a speed of600 r / min, and after stirringwas performed for 2 min, the componentA liquid was prepared; and

[0036] (2) preparation ofthe componentB liquid: atroom temperature (namely, 20°C-25°C), water was added to the waste phosphoric acid according to a required ratio, stirring was performed at a speed of600 r / min for 2 min, then the inorganic salts were added, and stirring was performed until the inorganic salts were completely dissolved to prepare the component B liquid.

[0037] When in use, the componentA liquid and the component B liquid were mixed in a mass ratio of3:1 to be injected into cracks which need to be reinforced, and various tests were performed after injection and solidication, as shown in Table 1.

[0038] Example 2:A liquid inorganic material includes componentA liquid andcomponent B liquid, where the componentA liquid includes in parts by mass: 80 parts ofpropenoic acid emulsion, 45 parts of diatomite and 2 parts of a stabilizer which is calcium-based bentonite; and the component B liquid specically includes in parts by mass: 15 parts of waste phosphoric acid, 105 parts of water, and 80 parts of inorganic salts which are magnesium chloride.

[0039] Specic preparation steps are:

[0040] (1) preparationofthecomponentA liquid: atroomtemperature (namely, 20°C25°C), the stabilizer and the diatomite were added into the propenoic acid emulsion according to a required ratio, stirringwas performed at a speed of600 r / min, and after stirringwas performed for 2 min, the componentA liquid was prepared; and

[0041] (2) preparation ofthe componentB liquid: atroom temperature (namely, 20°C25°C), water was added to the waste phosphoric acid according to a required ratio, stirring was performed at a speed of600 r / min for 2 min, then the inorganic salts were added, and stirring was performed until the inorganic salts were completely dissolved to prepare the component B liquid.

[0042] When in use, the componentA liquid and the component B liquid were mixed in a mass ratio of2: l to be injected into cracks which need to be reinforced, and various tests were performed after injection and solidication, as shown in Table 1.

[0043] Example 3: A composition and preparation process of component A liquid and component B liquid are identical to those in Embodiment 2, and the only difference is that inorganic salts are calcium chloride.

[0044] When in use, the componentA liquid and the component B liquid were mixed in a mass ratio of3:1 to be injected into cracks which need to be reinforced, and various tests were performed after injection and solidication, as shown in Table 1.

[0045] Example 4: A composition and preparation process of component A liquid and componentB liquid are identical to those in Embodiment 3.

[0046] When in use, the componentA liquid and the component B liquid were mixed in a mass ratio of4:1 to be injected into cracks which need to be reinforced, and various tests were performed after injection and solidication, as shown in Table l.

[0047] Example 5:A liquid inorganic material includes componentA liquid and component B liquid, where the componentA liquid includes in parts by mass: 80 parts ofpropenoic acid emulsion, 35 parts of diatomite and 1 part of a stabilizer which is calciumbased bentonite; and the component B liquid specically includes in parts by mass: 15 parts of waste phosphoric acid, 105 parts of water, and 80 parts of inorganic salts which are magnesium chloride.Apreparation process is the same as that in Embodiment 4;

[0048] When in use, the componentA liquid and the component B liquid were mixed in a mass ratio of3:1 to be injected into cracks whichneed to be reinforced, and various tests were performed after injection and solidication, as shown in Table l.

[0049] Example 6:A liquid inorganic material includes componentA liquid and component B liquid, where the componentA liquid includes in parts by mass: 80 parts ofpropenoic acid emulsion, 45 parts of diatomite and 2 part of a stabilizer which is calcium-based bentonite; and the component B liquid specically includes in parts by mass: 15 parts of waste phosphoric acid, 105 parts ofwater, and 80 parts ofinorganic saltswhich are sodium chloride; a component C is ultrane steel bers which consist of stainless steel bers, aluminum alloy steel bers, and silicon steel bers which are mixed in a quantity ratio of l:l:1.

[0050] Specic preparation steps are:

[0051] (1) preparationofthe componentA liquid: atroomtemperature (namely, 20°C-25°C), the stabilizer and the diatomite were added into the propenoic acid emulsion according to a required ratio, stirringwas performed at a speed of600 r / min, and after stirringwas performed for 2 min, the componentA liquid was prepared; and

[0052] (2) an appropriate quantity of the component C was selected and added to the componentA liquid, and stirring was performed at a speed of600 r / min until uniform mixing to obtain new componentA liquid;

[0053] (3) preparation ofthe componentB liquid: atroom temperature (namely, 20°C-25°C), water was to the waste phosphoric acid according to a required ratio, stirring was performed at a speed of 600 r / min for 2 min, then the inorganic salts were added, and stirring was performed until the inorganic salts were completely dissolved to prepare the component B liquid.

[0054] When in use, the componentA liquid and the component B liquid were mixed in a mass ratio of3:1 to be injected into cracks which need to be reinforced, and various tests were performed after injection and solidication, as shown in Table l. The microscopic schematic diagram after solidication is shown in FIG. 3.

[0055] Table 1 Test results ofvarious embodiments: Final nt Maximum Compone Compone Initial solidicati temperatur surface _ ntA ntB solidicatio on e before temperatu n time (s) strength reaction re (°C) (MPa) °C ( ) Example 1 13 33 24.8 28.6 1 Example 1.1 13 31 24.8 28.9 2 Example 1.1 16 37 24.8 29.1 3 Example 1.1 18 28 24.8 29.4 4 Example 1.1 12 19 24.8 28.7 5 Example 1.1 16 508 24.8 29.1 6

[0056] According to Table 1, comparing Example 1 with Example 3, it can be concluded that when other conditions are the same, the higher the concentration ofphosphoric acid is, the faster the initial solidication time ofthe material is, and the inorganic salts will affect the nal solidication strength; comparing Example 2 with Example 3 and Example 4, it can be concluded thatwhen mixing ratios are different and other conditions are the same, Example 3 has the best test results after comprehensive consideration; comparing Example 3 with Example 5, it can be concluded that the componentsA are different and other conditions are the same, the diatomite and the stabilizer can improve the nal solidication strength of the material; and in Example 6, the appropriate quantities of the component C are added on the basis of Example 3, thereby signicantly improving the strength of the material. After comprehensive consideration, it can be concluded that when the component A and the componentB are used in a mass ratio of 3: 1, best effects can be obtained. When small cracks are sealed and reinforced, the componentA liquid and the componentB liquid are mixed to be injected into an area which needs to be reinforced, and when the componentA liquid and the componentB liquid are cured, requirements for sealing and reinforcement strength can be met. When large cracks are sealed and reinforced, according to the actual situation of the cracks, appropriate quantities ofultrane steel bers are added to the componentA liquid, the ultrane steel bers and the componentA liquid are stirred and mixed uniformly to obtain new componentA liquid, and then, the new component liquid and the componentB liquid are mixed and injected into an areawhich needs to be reinforced. After thenew component liquid and the component B liquid are cured, the ultrane steel bers can effectively improve the strength after solidication, thereby ensuring the sealing and reinforcement effect on the large cracks.

[0057] In addition, the material in any ofthe above embodiments and the material without addition of the diatomite are subjected to reinforcement tests on the same cracks. After a period ofreinforcement, a microscopic comparison diagram for fracture growth is observed, as shown in FIG. 2. From the gure, it can be seen that the reinforcement material of the present invention with the addition of the diatomite has a signicantly better effect on controlling the fracture growth than the reinforcement material without the addition of the diatomite, which illustrates the role of the diatomite in the reinforcement material of the present invention.

[0058] The above are only preferred embodiments of the present invention. It should be noted that, for those ofordinary skill in the art, a plurality ofimprovements andmodications may be made without departing from the principle of the present invention, and the improvements and modications are also regarded to be within the protection scope of the present invention.

Claims

1. Liquid inorganic material for crack reinforcement that a Liquid component A and a Liquid component B, in which a mass ratio of the liquid component A to the liquid component B (2-4):1 is, in which the Liquid component A contains in parts by mass specifically: 75 to 90 parts adhesive, 30 to 50 parts diatomaceous earth and 1 to 5 parts stabilizer and in which the pH value of the liquid component A is 7 to 9 after mixing; and in which the Liquid component B contains in parts by mass specifically: 10 to 20 parts waste phosphoric acid, 50 to 150 parts water and 30 to 100 parts inorganic salt and in which the pH value of the liquid component B is 1 to 1.5 after mixing.

2. Liquid inorganic material for strengthening cracks according to Claim 1 further comprising a component C, wherein the component C is ultrafine steel fibers and in which an amount of added ultrafine steel fiber is suitable, depending on the size of the crack to be reinforced and the total amount introduced inorganic material, to improve the strength of the inorganic material after solidification improve.

3. Liquid inorganic material for strengthening cracks according to Claim 1, wherein the adhesive is acrylic emulsion.

4. Liquid inorganic material for strengthening cracks according to Claim 1, wherein the diatomaceous earth has a particle size of 100 to 150 mesh size.

5. Liquid inorganic material for strengthening cracks according to claim 1, wherein the pH value of the waste phosphoric acid is less than 1.

6. Liquid inorganic material for strengthening cracks according to Claim 1, wherein the stabilizer is sodium bentonite or calcium bentonite or a mixture of both is.

7. Liquid inorganic material for strengthening cracks according to Claim 1, wherein the inorganic salt is sodium chloride, magnesium chloride or calcium chloride, or a mixture thereof.

8. Liquid inorganic material for strengthening cracks according to claim 1, wherein the ultrafine steel fibers are made of stainless steel fibers, aluminum alloy fibers, silicon steel fibers, or a mixture thereof.

9. Method for preparing liquid inorganic material for the reinforcing cracks according to claim 1, comprising the following steps: (1) preparing a Liquid component A: adding at room temperature of stabilizer and diatomaceous earth to an acrylic emulsion in a required ratio and the Stir at a speed of 600 tpm for 2 minutes, after which the Liquid Component is obtained, poured into a container for later use, and making it possible to have the pH value between 7 and 9, (2) Preparation of Liquid Component B: Adding water to waste phosphoric acid at room temperature in a required ratio and stirring at a speed of 600 tpm for 2 minutes, then adding inorganic salt, stirring to completely dissolve the inorganic salt, after which Liquid Component B is obtained, poured into a container for later use, and making it possible to have the pH value between 1 and 1.

5. [[ID=??]] [[ID=??]] 1 / 3 Liquid inorganic A liquid inorganic material for crack reinforcement of Component A Component B Component B It should be noted that there are some unclear parts in the original text (such as the "??" marked lines), which may need further clarification to ensure more accurate translation.Component C Component C Component A Component B Waste Ultra fine corrugated Ultrafine corrugated steel fiber dhesive Inorganic Stabilizer Diatomite Water Adhesive diatomaceous earth water Waste phosphate inorganic salt stabilizer phosphoric steel fiber salt dimension acid Add a stabilizer and Add water to waste phosphoric acid, After adding water to waste phosphoric acid and stirring Perform appropriate According to the actual situation Add stabilizer to adhesive diatomite to an perform stirring, then add inorganic adding according to Add inorganic salt and stir to dissolve Add appropriate amount Mix the diatomaceous earth and stir until uniform. salts and perform stirring to dissolve an actual situation uniform stirring For large cracks: mix the For small cracks: mix the For large cracks: A and B components For small cracks: Group A, B component A with the component component A with the The mass ratio of (2-4): 1 is the mass ratio of (2-4): 1, B in a mass ratio of (2-4):1, and component B in a mass C component is appropriate and mixed Proportional mixing an appropriate quantity of the ratio of (2-4):1 for use component C for use FIG. 1