High-performance composite shield foaming agent and preparation method thereof

Abstract

The embodiment of the invention discloses a high-performance composite shield foaming agent and a preparation method thereof. The high-performance composite shield foaming agent comprises the following components in percentage by weight: 5%-8% of an anionic surfactant; 3%-7.5% of an ampholytic surfactant; 1.2%-2% of an auxiliary agent; 0.2%-0.5% of a thickening agent; 2%-5% of an anticoagulant; and the balance of solvent. The foaming agent provided by the invention has good stratum and engineering environment applicability. Particularly, the foaming agent has good tolerance to environment temperature, acid, alkali and salt, achieves high foaming ratio and stability, and can well meet muck improvement requirements under different working conditions in the tunneling process of the earth pressure balance type shield tunneling machine.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of shield foaming agents, and in particular to a high-performance composite shield foaming agent and a preparation method thereof. Background Art

[0002] In recent years, the construction of urban subways and underground space development projects has developed rapidly. As a commonly used shield construction method for underground space, earth pressure balance shield technology has the characteristics of wide application range of soil layers, small footprint, and low construction cost, and has become the first choice for today's urban subways. In order to achieve the smooth progress of earth pressure balance shield construction and ensure that the soil cut by the shield cutter disc forms a good "plastic flow" state after entering the soil bin, effective slag improvement technology is the key to ensuring the "plastic flow" of the soil. As the most advanced and effective soil improver in current soil improvement, foaming agent still has a lot of room for performance improvement.

[0003] In the process of subway shield construction, facing complex geological conditions, the selection of foaming agents is blind. Often, after discovering that the slag improvement is not good, the work is stopped to adjust the amount and type of foam, which causes great construction safety risks to the project. At present, the quality of foaming agent products on the market is uneven, and there is a lack of foaming agent products for different strata and different engineering environments. These foaming agent materials are difficult to ensure the rationality of shield construction slag improvement under complex strata. Therefore, it is very necessary to develop a high-performance composite shield foaming agent to deal with the above problems, which has broad market application value. Summary of the invention

[0004] To this end, an embodiment of the present invention provides a high-performance composite shield foaming agent and a preparation method thereof to solve the problem that the existing foaming agents have poor applicability to formations and engineering environments.

[0005] In order to achieve the above purpose, the embodiment of the present invention provides the following technical solutions:

[0006] According to a first aspect of an embodiment of the present invention, the present invention provides a high-performance composite shield foaming agent, wherein the high-performance composite shield foaming agent comprises the following raw materials by weight percentage:

[0007] Anionic surfactant: 5%~8%;

[0008] Amphoteric surfactant: 3%~7.5%;

[0009] Additives: 1.2%~2%;

[0010] Thickener: 0.2%~0.5%;

[0011] Anticoagulants: 2%~5%;

[0012] The balance is solvent.

[0013] Furthermore, the anionic surfactant is selected from one or both of sodium lauryl sulfate and sodium α-olefin sulfonate.

[0014] Furthermore, the amphoteric surfactant is selected from one or both of sodium fatty alcohol polyoxyethylene ether sulfonate and cocamidopropyl betaine.

[0015] Furthermore, the auxiliary agent is an alcohol ether modified polyhydroxy polymer.

[0016] Furthermore, the thickener is selected from one or both of xanthan gum and hydroxyethyl cellulose.

[0017] Furthermore, the anticoagulant is diethylene glycol butyl ether.

[0018] Furthermore, the solvent is deionized water.

[0019] Furthermore, the high-performance composite shield foaming agent comprises the following raw materials by weight percentage:

[0020] Anionic surfactant: 6%~6.5%;

[0021] Amphoteric surfactant: 3%~3.5%;

[0022] Additives: 1.2%~1.3%;

[0023] Thickener: 0.2%~0.3%;

[0024] Anticoagulants: 2%~2.5%;

[0025] The balance is solvent;

[0026] Or, the high-performance composite shield foaming agent comprises the following raw materials by weight percentage:

[0027] Anionic surfactant: 5%~5.5%;

[0028] Amphoteric surfactant: 5.5%~6.5%;

[0029] Additives: 1.4%~1.6%;

[0030] Thickener: 0.35%~0.4%;

[0031] Anticoagulants: 3.5%~4%;

[0032] The balance is solvent;

[0033] Or, the high-performance composite shield foaming agent comprises the following raw materials by weight percentage:

[0034] Anionic surfactant: 7%~8%;

[0035] Amphoteric surfactant: 7%~7.5%;

[0036] Additives: 1.8%~2%;

[0037] Thickener: 0.45%~0.5%;

[0038] Anticoagulants: 4.2%~5%;

[0039] The balance is solvent.

[0040] According to a second aspect of an embodiment of the present invention, the present invention provides a method for preparing a high-performance composite shield foaming agent as described in any one of the above items, the method comprising the following steps:

[0041] (1) Use a closed, temperature-controllable stainless steel reactor with double-layer stirring blades, and the inner wall temperature of the reactor is set at 80±2℃;

[0042] (2) Add the solvent into the reactor, and when the temperature rises to 80±2℃, turn on the stirring motor and control the stirring speed to 100~150r / min;

[0043] (3) Add anionic surfactant, amphoteric surfactant, auxiliary agent and anticoagulant in sequence from the feed port of the reactor, and add the next raw material after the previous raw material is dissolved;

[0044] (4) Finally, add the thickener. After the addition is completed, continue stirring for 60±5 min and cool naturally to room temperature to obtain the high-performance composite shield foam agent.

[0045] The embodiments of the present invention have the following advantages:

[0046] The foaming agent provided by the present invention can form a foam with high expansion rate and high stability after being diluted 20 times, and has good applicability to strata and engineering environments. In particular, it has good tolerance to ambient temperature, acid, alkali, and salt, achieves a high foaming ratio and stability, and can well meet the requirements for slag improvement under different working conditions during the excavation of an earth pressure balance shield machine. DETAILED DESCRIPTION

[0047] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] The present invention provides a high-performance composite shield foaming agent, which includes the following raw materials by weight percentage: anionic surfactant: 5% to 8%; amphoteric surfactant: 3% to 7.5%; auxiliary agent: 1.2% to 2%; thickener: 0.2% to 0.5%; anticoagulant: 2% to 5%; the balance is solvent. Among them:

[0049] Anionic surfactants are used to reduce the surface tension of liquids, making it easier for air to enter the liquid to form foam. Preferably, the anionic surfactant is selected from one or both of sodium dodecyl sulfate and sodium α-olefin sulfonate. In some specific embodiments, the anionic surfactant is composed of sodium dodecyl sulfate and sodium α-olefin sulfonate in a mass ratio of 1:2-4. Studies have found that the use of the above-mentioned anionic surfactants can significantly increase the foaming rate of the foaming agent while effectively enhancing the foam stability.

[0050] Amphoteric surfactants are used to further reduce the surface tension of the liquid and improve the ability and stability of foam generation. Preferably, the amphoteric surfactant is selected from one or both of sodium fatty alcohol polyoxyethylene ether sulfonate and cocamidopropyl betaine. In some specific embodiments, the amphoteric surfactant is composed of sodium fatty alcohol polyoxyethylene ether sulfonate and cocamidopropyl betaine in a mass ratio of 0.5-2:1. Studies have found that the use of the above-mentioned amphoteric surfactants can play a synergistic role with anionic surfactants, further improving the foam stability (long half-life) and low-temperature stability of the foaming agent.

[0051] The auxiliary agent is used to improve the uniformity of foam and enhance the stability of foam. Preferably, the auxiliary agent is an alcohol ether modified polyhydroxy polymer.

[0052] The thickener is used to adjust the foam consistency and enhance the structural stability of the foam. Preferably, the thickener is selected from one or both of xanthan gum and hydroxyethyl cellulose.

[0053] The anticoagulant is used to improve the low temperature stability of the foaming agent. Preferably, the anticoagulant is diethylene glycol butyl ether.

[0054] In some specific embodiments, the high-performance composite shield foam agent includes the following raw materials by weight percentage: anionic surfactant: 6%~6.5%; amphoteric surfactant: 3%~3.5%; auxiliary agent: 1.2%-1.3%; thickener: 0.2%~0.3%; anticoagulant: 2%~2.5%; the balance is solvent.

[0055] In some specific embodiments, the high-performance composite shield foam agent includes the following raw materials by weight percentage: anionic surfactant: 5%~5.5%; amphoteric surfactant: 5.5%~6.5%; auxiliary agent: 1.4%~1.6%; thickener: 0.35%~0.42%; anticoagulant: 3.5%~4%; the balance is solvent.

[0056] In some specific embodiments, the high-performance composite shield foam agent includes the following raw materials by weight percentage: anionic surfactant: 7%~8%; amphoteric surfactant: 7%~7.5%; auxiliary agent: 1.8%~2%; thickener: 0.45%~0.5%; anticoagulant: 4.2%~5%; the balance is solvent.

[0057] The technical solution of the present application is described in detail below through specific embodiments:

[0058] Unless otherwise specified, the technical means used in the present invention are conventional means well known to those skilled in the art, and the various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0059] Example 1

[0060] The present embodiment provides a high-performance composite shield foaming agent, whose raw materials are, by weight percentage: 2% sodium lauryl sulfate, 4% sodium α-olefin sulfonate, 1% sodium fatty alcohol polyoxyethylene ether sulfonate, 2% cocoamidopropyl betaine, 1.2% alcohol ether modified polyhydroxy polymer, 0.1% xanthan gum, 0.1% hydroxyethyl cellulose, 2% diethylene glycol butyl ether, and 87.6% deionized water.

[0061] The preparation method of the high-performance composite shield foaming agent comprises the following steps:

[0062] (1) A closed, temperature-controllable stainless steel reactor with double-layer stirring blades is used, and the inner wall temperature of the reactor is set at 80±2℃.

[0063] (2) Taking the production of 1000kg of product as an example, first add 876kg of deionized water into the reactor. When the temperature rises to 80±2℃, turn on the stirring motor and control the stirring speed to 120r / min.

[0064] (3) Add 20 kg of sodium dodecyl sulfate from the feed port of the reactor and control the stirring time to 30 ± 5 min. Observe whether there is obvious dissolved solid content in the transparent viewport of the reactor, and randomly take 3-5 samples to observe whether they are transparent before dissolving the next raw material.

[0065] Use the same method as sodium lauryl sulfate to add 40kg of sodium α-olefin sulfonate, 10kg of sodium fatty alcohol polyoxyethylene ether sulfonate, 20kg of cocamidopropyl betaine, 12kg of alcohol ether modified polyhydroxy polymer and 20kg of diethylene glycol butyl ether in sequence. After each raw material is dissolved / reacted, observe whether there is obvious dissolved solid component in the transparent viewport of the reactor, and randomly take 3-5 samples to observe whether it is transparent before dissolving the next raw material. Otherwise, increase the stirring time until the above requirements are met before adding the next raw material.

[0066] (4) Finally, add 1 kg of xanthan gum and 1 kg of hydroxyethyl cellulose to the reactor at a rate of 0.5 kg to 1 kg per minute. The two raw materials can be added separately or mixed in advance before adding. After all the thickeners are added, continue stirring for 60 ± 5 min. After all the above raw materials are dissolved and the reaction is completed, cool naturally to room temperature to obtain a high-performance composite shield foaming agent.

[0067] Example 2

[0068] The present embodiment provides a high-performance composite shield foaming agent, whose raw materials are, by weight percentage: 1% sodium lauryl sulfate, 4% sodium α-olefin sulfonate, 4% sodium fatty alcohol polyoxyethylene ether sulfonate, 2% cocoamidopropyl betaine, 1.4% alcohol ether modified polyhydroxy polymer, 0.1% xanthan gum, 0.3% hydroxyethyl cellulose, 4% diethylene glycol butyl ether, and 83.2% deionized water.

[0069] The preparation method of the above-mentioned high-performance composite shield foaming agent is the same as that of Example 1.

[0070] Example 3

[0071] The present embodiment provides a high-performance composite shield foaming agent, whose raw materials are, by weight percentage: 2% sodium lauryl sulfate, 6% sodium α-olefin sulfonate, 3.5% sodium fatty alcohol polyoxyethylene ether sulfonate, 4% cocoamidopropyl betaine, 2% alcohol ether modified polyhydroxy polymer, 0.3% xanthan gum, 0.2% hydroxyethyl cellulose, 5% diethylene glycol butyl ether, and 77% deionized water.

[0072] The preparation method of the above-mentioned high-performance composite shield foaming agent is the same as that of Example 1.

[0073] Test Example 1

[0074] Test standards and methods

[0075] Appearance: Visual inspection.

[0076] Apparent viscosity: GB / T 2794-2022 Determination of viscosity of adhesives.

[0077] pH: measured using a pH meter.

[0078] Foaming ratio: dilute the foaming agent 20 times with deionized water to prepare the test solution, and use the stirring method (Wαring-Blender) and airflow method (shield machine foam generator device) to test the foaming ratio.

[0079] Half-life: Dilute the foaming agent 20 times with deionized water to prepare the test solution. In the process of foaming by airflow method, control the foaming ratio to 10 (that is, the foam volume reaches 10 times the volume of the test solution), fill the foam in a container with a diameter of 11.4cm and a height of 20cm, and record the time required when the liquid in the foam precipitates and reaches half of the total mass of the liquid.

[0080] Low temperature stability: The critical temperature K at which the properties of the foam sample do not change significantly after refrigeration for 10 days is tested by the gradient cooling method. f .

[0081] Acid resistance, alkali resistance and salt resistance stability: dilute the foaming agent 20 times with deionized water to prepare a test solution, use citric acid as an additive for acid resistance test to adjust the pH value of the test solution to 4, use sodium hydroxide as an additive for alkali resistance test to adjust the pH value of the test solution to 12, and use sodium chloride as an additive for salt resistance test to prepare a test solution with a salt concentration of 5%.

[0082] The decrease in foaming ratio (R f ) and half-life reduction (R t ) to evaluate the influence of acid, alkali or salt on the foaming property and stability of the foaming agent, among which R f and R t The calculation formulas are shown in formula (1) and formula (2). f ≤5%, R t ≤20% is qualified, the smaller the value, the better the performance.

[0083] R f = (FER 1 / FER 0 )×100% (1)

[0084] R t = ( T h1 / T h0 )×100% (2)

[0085] Where: FER 1 , T h1 They represent the expansion ratio (airflow method) and half-life after the addition of additives;

[0086] FER 0 , T h0They represent the foaming ratio (airflow method) and half-life without adding any reagents.

[0087] The test results of the high performance composite shield foaming agent of Examples 1-3 are shown in Table 1 below.

[0088] Table 1 Test results

[0089]

[0090] Note: R f R is the average value of the decrease in foaming ratio after adding acid, alkali and salt to the test solution. t It is the average value of the decrease in half-life after adding acid, base and salt to the test solution respectively.

[0091] The results are as follows:

[0092] Example 1: This formula is a low-cost, high-foaming, low-stability, low-temperature stable, acid-base-salt resistant formula, and has good tolerance to high-concentration acids, alkalis and salts. This formula can be stored for a long time at an ambient temperature not lower than 2°C, and can ensure good foaming and foam stabilization effects. At room temperature, the foaming agent is a colorless transparent liquid with an apparent viscosity of 2mPa.s and a pH value of 7.2±0.1.

[0093] Example 2: This formula is a moderately cost-effective, high foaming, medium stability, low temperature stable, acid, alkali and salt resistant formula, and has good tolerance to high concentrations of acid, alkali and salt. This formula can be stored for a long time when the ambient temperature is not lower than 0°C, and can ensure good foaming and foam stabilization effects. At room temperature, the foaming agent is a colorless transparent liquid with an apparent viscosity of 2mPa.s and a pH value of 7.2±0.1.

[0094] Example 3: This formula is a high-cost, medium foaming, high-stability, low-temperature stable, acid, alkali and salt resistant formula, and has good tolerance to high concentrations of acid, alkali and salt. This formula can be stored for a long time when the ambient temperature is not less than 2°C, and can ensure good foaming and foam stabilization effects. At room temperature, the foaming agent is a light yellow transparent liquid with an apparent viscosity of 25mPa.s and a pH value of 7.4±0.1.

[0095] Comparative Example 1

[0096] This comparative example provides a high-performance composite shield foaming agent, which differs from Example 1 in that sodium dodecyl sulfate is replaced by an equal amount of dodecyl dimethyl hydroxyethyl ammonium chloride, and sodium α-olefin sulfonate is replaced by an equal amount of hexadecyl trimethyl ammonium bromide.

[0097] The performance test was performed according to the method in Test Example 1, and the results are as follows:

[0098] Stirring method-foaming ratio: 4.3;

[0099] Airflow method-foaming ratio: 12;

[0100] Half-life: 12.6 min;

[0101] Low temperature stability: K f = 6°C;

[0102] R f =15%, R t =17%.

[0103] Compared with Example 1, the foaming ratio and half-life of Comparative Example 1 are significantly reduced, and the acid resistance, alkali resistance and salt resistance of R f There is also a decrease in K f The larger it is, the worse the low temperature stability is.

[0104] Comparative Example 2

[0105] This comparative example provides a high-performance composite shield foaming agent, which differs from Example 2 in that the sodium fatty alcohol polyoxyethylene ether sulfonate is replaced by an equal amount of lauryl amide propyl dimethyl amine oxide, and the cocoamidopropyl betaine is replaced by an equal amount of dodecyl hydroxysulfonate betaine.

[0106] The performance test was performed according to the method in Test Example 1, and the results are as follows:

[0107] Stirring method-foaming ratio: 6.1;

[0108] Airflow method-foaming ratio: 30;

[0109] Half-life: 12.6 min;

[0110] Low temperature stability: K f =10℃;

[0111] R f =4%, R t =10%.

[0112] Compared with Example 2, the half-life and low-temperature stability of Comparative Example 2 are significantly reduced, and the foaming performance and acid resistance, alkali resistance, and salt resistance are not significantly affected.

[0113] Comparative Example 3

[0114] The comparative example provides a high-performance composite shield foaming agent, whose raw materials are, by weight percentage, 1% sodium lauryl sulfate, 5% sodium α-olefin sulfonate, 3% sodium fatty alcohol polyoxyethylene ether sulfonate, 5% cocoamidopropyl betaine, 2.4% alcohol ether modified polyhydroxy polymer, 0.3% xanthan gum, 0.05% hydroxyethyl cellulose, 2.5% diethylene glycol butyl ether, and 77.25% deionized water.

[0115] The performance test was performed according to the method in Test Example 1, and the results are as follows:

[0116] Stirring method-foaming ratio: 4.1;

[0117] Airflow method-foaming ratio: 13.5;

[0118] Half-life: 20.5min;

[0119] Low temperature stability: K f = 15℃;

[0120] R f =3%, R t =25%.

[0121] Compared with Example 3, the foaming ratio and half-life of Comparative Example 3 are smaller, and the acid resistance, alkali resistance, salt resistance and low temperature stability are poor. During the test, the foam generation quality is poor, and liquid precipitation is easy to occur after mixing with the slag. The foaming agent under this formula is difficult to make the slag form a good plastic flow state.

[0122] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A high-performance composite shield foaming agent, characterized in that: The high-performance composite shield foaming agent comprises the following raw materials by weight percentage: Anionic surfactant: 5%~8%; Amphoteric surfactant: 3%~7.5%; Additives: 1.2%~2%; Thickener: 0.2%~0.5%; Anticoagulants: 2%~5%; The balance is solvent.

2. The high-performance composite shield foaming agent according to claim 1, characterized in that: The anionic surfactant is selected from one or both of sodium lauryl sulfate and sodium α-olefin sulfonate.

3. The high-performance composite shield foaming agent according to claim 1, characterized in that: The amphoteric surfactant is selected from one or two of sodium fatty alcohol polyoxyethylene ether sulfonate and cocamidopropyl betaine.

4. The high-performance composite shield foaming agent according to claim 1, characterized in that: The auxiliary agent is an alcohol ether modified polyhydroxy polymer.

5. The high-performance composite shield foaming agent according to claim 1, characterized in that: The thickener is selected from one or both of xanthan gum and hydroxyethyl cellulose.

6. The high-performance composite shield foaming agent according to claim 1, characterized in that: The anticoagulant is diethylene glycol butyl ether.

7. The high-performance composite shield foaming agent according to claim 1, characterized in that: The solvent is deionized water.

8. The high-performance composite shield foaming agent according to claim 1, characterized in that: The high-performance composite shield foaming agent comprises the following raw materials by weight percentage: Anionic surfactant: 6%~6.5%; Amphoteric surfactant: 3%~3.5%; Additives: 1.2%~1.3%; Thickener: 0.2%~0.3%; Anticoagulants: 2%~2.5%; The balance is solvent; Or, the high-performance composite shield foaming agent comprises the following raw materials by weight percentage: Anionic surfactant: 5%~5.5%; Amphoteric surfactant: 5.5%~6.5%; Additives: 1.4%~1.6%; Thickener: 0.35%~0.4%; Anticoagulants: 3.5%~4%; The balance is solvent; Or, the high-performance composite shield foaming agent comprises the following raw materials by weight percentage: Anionic surfactant: 7%~8%; Amphoteric surfactant: 7%~7.5%; Additives: 1.8%~2%; Thickener: 0.45%~0.5%; Anticoagulants: 4.2%~5%; The balance is solvent.

9. The method for preparing the high-performance composite shield foaming agent according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: (1) Use a closed, temperature-controllable stainless steel reactor with double-layer stirring blades, and the inner wall temperature of the reactor is set at 80±2℃; (2) Add the solvent into the reactor, and when the temperature rises to 80±2℃, turn on the stirring motor and control the stirring speed to 100~150r / min; (3) Add anionic surfactant, amphoteric surfactant, auxiliary agent and anticoagulant in sequence from the feed port of the reactor, and add the next raw material after the previous raw material is dissolved; (4) Finally, add the thickener. After the addition is completed, continue stirring for 60±5 min and cool naturally to room temperature to obtain the high-performance composite shield foam agent.

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