Liquid quick-setting agent and preparation method thereof

Abstract

The present invention provides a liquid accelerator and a preparation method thereof, relating to the technical field of accelerator preparation. The preparation method of the liquid accelerator comprises the following steps: 1) preparing a liquid sodium aluminate solution; 2) adding a modified fluoride salt: adding water to the liquid sodium aluminate solution and stirring uniformly; then adding the modified fluoride salt to the liquid sodium aluminate solution, stirring, and reacting at 50-80°C for 0.5-1 hour; 3) adding aluminum sulfate: within 10-30 minutes after the fluoride salt reacts completely, adding aluminum sulfate and continuing the reaction for 1-2 hours; 4) adding an organic alcohol amine and stirring for 0.5-1 hour to prepare the liquid accelerator, which has good viscosity stability.

Description

Technical Field

[0001] The present invention relates to the technical field of quick-setting agent preparation, in particular to a liquid quick-setting agent and a preparation method thereof. Background Art

[0002] Accelerators are chemical admixtures that promote the rapid setting of cement or concrete. Based on their appearance, accelerators can be divided into powdered and liquid forms. Liquid accelerators are suitable for shotcrete construction, underwater concrete, and leak repair and rescue projects. Liquid accelerators are recognized in the market for their ability to significantly improve working conditions without the dust pollution associated with powdered accelerators.

[0003] However, after the liquid accelerator is prepared, the accelerator that is not used up in one project needs to be temporarily stored for use in the next project. However, during the storage process, it is found that the viscosity of the liquid accelerator changes with the storage time and the stability is poor, which affects the performance of the accelerator. Summary of the Invention

[0004] (1) Technical problems solved

[0005] In view of the deficiencies in the prior art, the present invention provides a liquid accelerating setting agent and a preparation method thereof, which solve the technical problem of poor viscosity stability of the liquid accelerating setting agent.

[0006] (2) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A method for preparing a liquid accelerating setting agent comprises the following steps:

[0009] 1) preparing a liquid sodium aluminate solution;

[0010] 2) Adding modified fluoride salt: adding water to the liquid sodium aluminate solution and stirring evenly; then adding the modified fluoride salt to the liquid sodium aluminate solution, stirring, and reacting at 50-80° C. for 0.5-1 hour;

[0011] 3) Adding aluminum sulfate: After the fluoride salt reacts completely, add aluminum sulfate and continue the reaction for 1 to 2 hours;

[0012] 4) adding organic alcohol amine and stirring for 0.5 to 1 hour to obtain the liquid accelerating setting agent.

[0013] Preferably, the modified fluoride salt comprises: silica gel and fluoride salt, and the mass ratio of the silica gel to the fluoride salt is 1-5:95-99.

[0014] Preferably, the liquid sodium aluminate solution comprises sodium hydroxide and aluminum hydroxide, and the mass ratio of the sodium hydroxide to the aluminum hydroxide is 1:1.2 to 1.5.

[0015] Preferably, the mass concentration of the liquid sodium aluminate is 55-65%.

[0016] Preferably, the fluoride salt includes sodium fluoride, sodium fluorosilicate, and magnesium fluorosilicate, and the mass ratio of the sodium fluoride, sodium fluorosilicate, and magnesium fluorosilicate is (1-2): (5-7): (2-3).

[0017] Preferably, the fluoride salt includes sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate, and the mass ratio of the sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate is 1.5:6:2.5.

[0018] On the other hand, a liquid accelerating setting agent prepared by the preparation method, wherein the weight ratio of the liquid accelerating setting agent is:

[0019]

[0020] Preferably, the viscosity of the liquid quick-setting agent at room temperature is 40-55 cP.

[0021] Preferably, the viscosity of the liquid quick-setting agent at room temperature after storage for 60 days is 45-60 cP.

[0022] (3) Beneficial effects

[0023] The present invention provides a liquid accelerating agent and a preparation method thereof. Compared with the prior art, the present invention has the following beneficial effects:

[0024] During the preparation of the liquid accelerator, a liquid sodium aluminate solution and a modified fluoride salt are first added, followed by aluminum sulfate. The liquid sodium aluminate solution hydrolyzes, making the solution alkaline and promoting the hydrolysis of the fluoride salt to form silica gel and fluoride ions. The modified fluoride salt includes silica gel, which can reduce the hydrolysis rate of the fluoride salt, thereby reducing the rate of fluoride ion generation, ensuring that the solution contains only a small amount of fluoride ions in the initial hydrolysis stage. Under these conditions, the addition of aluminum sulfate reduces the fluoride ion concentration and prevents the rapid formation of aluminum fluoride particles and their subsequent aggregation into large precipitates. During storage of the prepared liquid accelerator, the silica gel encapsulates the fluoride ions produced by hydrolysis, continuously reducing the probability of fluoride ions and aluminum ions combining, thereby preventing the small aluminum fluoride particles generated during storage from slowly agglomerating into large particles, which would affect the viscosity of the liquid accelerator. As a result, the viscosity of the liquid accelerator does not change significantly during storage, and the viscosity stability is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a photograph of the liquid quick-setting admixture prepared in Example 1 after standing for 60 days;

[0027] Figure 2 This is a photo of the liquid quick-setting agent prepared in Comparative Example 1 after it was left to stand for 60 days. DETAILED DESCRIPTION

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0029] The embodiments of the present application provide a liquid accelerating setting agent and a preparation method thereof, thereby solving the technical problem that the viscosity stability of the liquid accelerating setting agent is poor, which affects the performance of the accelerating setting agent.

[0030] The technical solution in the embodiments of the present application is to solve the above technical problems, and the overall idea is as follows:

[0031] During the preparation of the liquid accelerator, a liquid sodium aluminate solution and a modified fluoride salt are first added, followed by aluminum sulfate. The liquid sodium aluminate solution hydrolyzes to an alkaline state, causing the fluoride salt to hydrolyze to form silica gel. The modified silica gel slows the hydrolysis rate of the fluoride salt and the generation of fluoride ions, ensuring that fewer fluoride ions are produced during the initial hydrolysis phase. Under these conditions, the addition of aluminum sulfate prevents the rapid generation of aluminum fluoride particles and their subsequent aggregation into large precipitates due to the low fluoride ion concentration. During storage of the prepared liquid accelerator, the silica gel encapsulates the fluoride ions generated by hydrolysis, continuously reducing the probability of fluoride and aluminum ions binding. This prevents the small aluminum fluoride particles generated during storage from slowly agglomerating into larger particles, which could affect the viscosity of the liquid accelerator. Consequently, the viscosity of this liquid accelerator system is highly stable.

[0032] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0033] Example 1:

[0034] This embodiment provides a method for preparing a liquid accelerating setting agent, comprising the following steps:

[0035] 1) preparing a liquid sodium aluminate solution: adding aluminum hydroxide, sodium hydroxide, and sodium hydroxide in a mass ratio of 1:1.3, heating to 95° C., and keeping warm for 1.2 hours to obtain a liquid sodium aluminate solution with a mass concentration of 56%;

[0036] 2) Adding modified fluoride salt: Mix silica gel and fluoride salt in a mass ratio of 1:95 to obtain modified fluoride salt; add water to the liquid sodium aluminate solution and stir evenly; then add the modified fluoride salt to the liquid sodium aluminate solution, stir, and react at 55°C for 0.6h;

[0037] The fluoride salt includes sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate, and the mass ratio of sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate is 1.1:5.5:2.3;

[0038] 3) Add aluminum sulfate: After the fluoride salt reacts completely and the system becomes uniformly milky white, add aluminum sulfate within 11 minutes and continue the reaction for 1.1 hours;

[0039] 4) Adding organic alcohol amine: Add organic alcohol amine and stir for 0.6 hours to obtain a liquid accelerating setting agent.

[0040] The prepared liquid quick-setting agent has good fluidity and no sediment.

[0041] Example 2:

[0042] This embodiment provides a method for preparing a liquid accelerating setting agent, comprising the following steps:

[0043] 1) preparing a liquid sodium aluminate solution: adding aluminum hydroxide, sodium hydroxide, and sodium hydroxide in a mass ratio of 1:1.4, heating to 105° C., and keeping warm for 1.6 hours to obtain a liquid sodium aluminate solution with a mass concentration of 59%;

[0044] 2) Adding modified fluoride salt: Mix silica gel and fluoride salt in a mass ratio of 3:95 to obtain modified fluoride salt; add water to the liquid sodium aluminate solution and stir evenly; then add the modified fluoride salt to the liquid sodium aluminate solution, stir, and react at 65°C for 0.8h;

[0045] The fluoride salt includes sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate, and the mass ratio of sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate is 1.6:6.2:2.6;

[0046] 3) Adding aluminum sulfate: within 25 minutes after the fluoride salt has reacted completely, add aluminum sulfate and continue the reaction for 1.6 hours;

[0047] 4) Adding organic alcohol amine: adding organic alcohol amine and stirring for 0.8h to prepare the liquid accelerating setting agent.

[0048] The prepared liquid quick-setting admixture is in good condition and has no sediment.

[0049] Example 3

[0050] This embodiment provides a method for preparing a liquid accelerating setting agent, comprising the following steps:

[0051] 1) preparing a liquid sodium aluminate solution: adding aluminum hydroxide, sodium hydroxide, and sodium hydroxide in a mass ratio of 1:1.5, heating to 110° C., and keeping warm for 2 hours to obtain a liquid sodium aluminate solution with a mass concentration of 65%;

[0052] 2) Adding modified fluoride salt: Mix silica gel and fluoride salt in a mass ratio of 5:95 to obtain modified fluoride salt; add water to the liquid sodium aluminate solution and stir evenly; then add the modified fluoride salt to the liquid sodium aluminate solution, stir, and react at 75°C for 1 hour;

[0053] The fluoride salt includes sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate, and the mass ratio of sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate is 2:7:3;

[0054] 3) Adding aluminum sulfate: within 30 minutes after the fluoride salt has reacted completely, add aluminum sulfate and continue the reaction for 2 hours;

[0055] 4) Adding organic alcohol amine: adding organic alcohol amine and stirring for 1 hour to prepare the liquid accelerating setting agent.

[0056] The prepared liquid quick-setting admixture is in good condition and has no sediment.

[0057] Comparative Example 1

[0058] The difference between Comparative Example 1 and Example 1 is that the fluoride salt is not modified in step 2, and the liquid accelerating admixture is prepared using the fluoride salt. The rest is the same as in Example 1.

[0059] The prepared liquid quick-setting agent has good fluidity and no sediment.

[0060] Comparative Example 2

[0061] The difference between Comparative Example 2 and Example 1 is that step 3 and step 2 are swapped, aluminum sulfate is added first, and then the modified fluoride salt is added. The rest is the same as Example 1.

[0062] The prepared liquid quick-setting admixture produces a precipitate.

[0063] The viscosity stability of the liquid quick-setting agents prepared in Examples 1 to 3 and Comparative Examples 1 and 2 was tested. The results are shown in Table 1.

[0064] Viscosity stability test method:

[0065] The viscosity of the prepared liquid quick-setting agent is measured using a rotational viscometer and recorded as the initial viscosity.

[0066] The prepared liquid accelerator is left to stand at room temperature and pressure for 60 days, and then its viscosity is tested and recorded as the 60-day viscosity;

[0067] Compare the 60-day viscosity value with the initial viscosity value to determine viscosity stability:

[0068] 1. |60-day viscosity value - initial viscosity value| / initial viscosity value × 100% ≤ 20%, good viscosity stability;

[0069] 2. 20%<|60-day viscosity value-initial viscosity value| / initial viscosity value×100%≤50%, the viscosity stability is qualified;

[0070] 3. 50% < |60-day viscosity value - initial viscosity value| / initial viscosity value × 100%, viscosity stability is unqualified.

[0071] Table 1. Viscosity stability test results of prepared liquid quick-setting agent

[0072]

[0073] Depend on Figure 1 It can be seen that after the liquid quick-setting agent prepared in Example 1 was left to stand for 60 days, the flow state of the liquid was still very good when it was turned upside down, that is, its viscosity value did not increase much, and the viscosity stability was good. Figure 2 It can be seen that after the liquid accelerator prepared in Comparative Example 1 was left to stand for 60 days, the fluidity of the liquid when inverted was poor, its viscosity value increased significantly, and its viscosity stability was poor. The results in Table 1 also show that the viscosity stability of the liquid accelerators prepared in Examples 1 to 3 was good; the viscosity stability of the liquid accelerators prepared in Comparative Examples 1 and 2 was unqualified. Therefore, the viscosity stability of the liquid accelerator prepared directly without modifying the fluoride salt was poor. However, the viscosity stability was also poor when aluminum sulfate was added first and then the modified fluoride salt was added. However, the viscosity stability of the liquid accelerator prepared by modifying the fluoride salt and adding the modified fluoride salt first and then the aluminum sulfate was good. Under the synergistic conditions of the two, the viscosity stability of the prepared liquid accelerator was good.

[0074] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0075] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for preparing a liquid accelerating setting agent, characterized in that: The steps include: 1) preparing a liquid sodium aluminate solution; 2) Adding modified fluoride salt: adding water to the liquid sodium aluminate solution and stirring evenly; then adding the modified fluoride salt to the liquid sodium aluminate solution, stirring, and reacting at 50-80° C. for 0.5-1 hour; 3) Adding aluminum sulfate: After the fluoride salt reacts completely, add aluminum sulfate and continue the reaction for 1 to 2 hours; 4) adding organic alcohol amine and stirring for 0.5 to 1 hour to obtain the liquid accelerating setting agent; The modified fluoride salt comprises: silica gel and fluoride salt; The fluoride salt includes sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate, and the mass ratio of the sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate is (1-2): (5-7): (2-3).

2. The preparation method according to claim 1, wherein The mass ratio of the silica gel to the fluoride salt is 1-5:95-99.

3. The preparation method according to claim 1, wherein The liquid sodium aluminate solution includes sodium hydroxide and aluminum hydroxide, and the mass ratio of the sodium hydroxide to the aluminum hydroxide is 1:1.2-1.

5.

4. The preparation method according to claim 1, wherein The mass concentration of the liquid sodium aluminate is 55-65%.

5. The preparation method according to claim 1, wherein The fluoride salt includes sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate, and the mass ratio of the sodium fluoride, sodium fluorosilicate and magnesium fluorosilicate is 1.5:6:2.

5.

6. A liquid quick-setting admixture prepared by the preparation method according to any one of claims 1 to 5, characterized in that: The weight ratio of each component of the liquid quick-setting agent is:

7. The liquid quick-setting admixture according to claim 6, wherein The viscosity of the liquid quick-setting agent at room temperature is 40-55 cP.

8. The liquid quick-setting admixture according to claim 6, wherein The viscosity of the liquid quick-setting agent at room temperature after being stored for 60 days is 45-60 cP.

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