A method for rapid construction of a microemulsion surfactant complex system

Abstract

The application discloses a method for rapidly constructing a microemulsion surfactant composite system, first determines a formula of surfactants in the surfactant composite system, carries out a laboratory microemulsion phase behavior experiment, obtains an optimal salinity S * , calculates hydrophilic-lipophilic deviation values HLD corresponding to different salinities, preliminarily determines a salinity range of a middle-phase microemulsion and upper and lower boundaries of the HLD values according to a phase transition point, after indoor phase behavior data are measured, an optimized unknown quantity calculation method is used to improve the HLD-NAC state equation, the HLD-NAC state equation is extended to the phase behavior prediction of the microemulsion system after adjustment parameters, meanwhile, the upper and lower boundaries of the HLD values calculated in theory, and a quantitative solubilization ratio and a volume of the solubilized oil phase / water phase are obtained. The corrected model can rapidly and highly accurately predict a microemulsion system type, and provides a theoretical guidance for the application of the microemulsion surfactant system to different types of oil reservoirs. The method has a practical significance for screening and constructing a surfactant composite system for forming a microemulsion.

Description

Technical Field

[0001] This invention relates to the field of petrochemical technology, and in particular to a rapid construction method for a microemulsion surfactant composite system. Background Technology

[0002] Chemical flooding is currently the main method of tertiary oil recovery, with surfactant flooding being a primary approach. The ability to reduce interfacial tension is a crucial indicator for screening surfactant systems. Based on this, microemulsion systems with low / ultra-low interfacial tension have demonstrated superior enhanced oil recovery capabilities through experimental testing and field applications. Microemulsions are thermodynamically stable and transparent dispersions formed by two immiscible liquids, with particle sizes ranging from 10 to 100 nm. In the past few decades, mid-phase microemulsions have gained attention due to their ultra-low interfacial tension (10 nm). -3 mN / m) and solubilizing and emulsifying properties have always been the goals pursued by surfactant-based oil displacement systems.

[0003] Microemulsion systems have high requirements for surfactant concentration and structure, and the screening process is complex, making it difficult to obtain microemulsion surfactant composite systems suitable for reservoir conditions solely through experimental methods. In recent years, scholars both domestically and internationally have proposed empirical and semi-empirical formulas to quantify the formation conditions of microemulsions. The hydrophilic-lipophilic deviation method (HLD) and net mean curvature (NAC) can be used to calculate and determine the phase behavior of microemulsions under different variables such as salinity, temperature, oil phase, and surfactant, thereby designing optimal microemulsion surfactant formulations. International scholars have proposed the HLD-NAC equation of state, linking experiments and calculations to predict the phase behavior and effects of microemulsions. This method is applicable to surfactant systems with known surfactant structures, characteristic lengths, and head group surface areas, especially single surfactant systems. For mature commercial surfactants, this method has certain application value. However, due to the limitations of semi-empirical formulas, there are many unknowns and a wide range of variable adjustability during the calculation process. Furthermore, laboratory experiments also face practical problems such as a large number of groups, long time duration, and the need for a single, fixed system. For complex surfactant systems, especially those with unknown surfactant characteristic values ​​(e.g., petroleum sulfonates widely used in Chinese oilfields), this method still cannot solve for the unknowns in the equations. Furthermore, there remains a gap between the phase behavior windows shown by theoretical calculations and actual experiments. Therefore, how to specifically handle unknown variables, optimize the cascading relationship between calculations and experiments, and develop a novel method for the rapid construction of microemulsion surfactant complex systems remains an unsolved problem. Summary of the Invention

[0004] To address the problems of complex, cumbersome, time-consuming, and labor-intensive processes in current methods for constructing microemulsion surfactant composite systems suitable for reservoir conditions, this invention provides a rapid method for constructing microemulsion surfactant composite systems.

[0005] The rapid construction method of the microemulsion surfactant composite system provided by the present invention comprises the following steps:

[0006] S1. Determine the types of surfactants in the surfactant composite system and conduct laboratory microemulsion phase behavior experiments. Set up no fewer than 5 experimental sites (groups). Obtain the optimal salinity S through salinity scanning experiments. * Optimal salinity S * The corresponding hydrophilic-lipophilic deviation value (HLD) is equal to 0. Calculate the hydrophilic-lipophilic deviation value (HLD) corresponding to different salinities (S), and preliminarily determine the salinity range of the middle-phase microemulsion [S] based on the phase transition point. L S U And the upper and lower bounds of the HLD value HLD L测 HLD U测 Determine the volume V of the solubilized aqueous phase corresponding to the lower boundary of HLD. wm测 The volume V of the solubilized oil phase corresponding to the upper boundary of HLD om测 .

[0007] The formula for calculating the hydrophilicity-lipophilicity deviation (HLD) value corresponding to different salinities S is as follows:

[0008]

[0009] In the formula, S is the salinity, NaCl g / 100mL; S* is the optimal salinity, corresponding to an HLD value of 0, NaCl g / 100mL.

[0010] S2. Define a parameter B, let... In the formula, M W a is the molecular weight of the surfactant, in g / mol; S This represents the surface area of ​​a single surfactant molecule. L is the full extension length of the tail group of the surfactant. Due to L, a S M w The three parameters are unknown; therefore, the following method is used to solve for the value of B:

[0011] S21. Calculate the upper and lower bounds of HLD. L测 HLD U测 The corresponding B value, B L and B U And solve for B corresponding to each experimental test point. XThe value X takes the values ​​1, 2, 3, ..., X, where X ≥ 5, meaning the number of experimental points (groups) set is no less than 5; the calculation formula is as follows:

[0012]

[0013]

[0014]

[0015] In the formula, σ * The optimal solubilization ratio corresponding to the optimal salinity was determined through experiments on the phase behavior of microemulsions; N a Here is Avogadro's constant, with a value of 6.023 × 10⁻⁶. 23 V s The volume of the surfactant is in cm. 3 V om V is the volume of the oil phase dissolved in the microemulsion obtained in the experiment. om测 V wm V is the volume of the aqueous phase dissolved in the microemulsion obtained in the experiment. wm测 ;

[0016] S22. Let the initial value be B0 = B min Let the step size ΔB = 0.01 × (B max -B min ); B min For B X B L B U The minimum value in; B max For B X B L B U The maximum value in the range; substitute the B0 value into the following formula to calculate the solubilization ratio σ. io算 and σ iw算 ;

[0017]

[0018]

[0019] In the formula, σ * The optimal solubilization ratio corresponding to the optimal salinity was determined through experiments on the phase behavior of microemulsions; N a Here is Avogadro's constant, with a value of 6.023 × 10⁻⁶. 23 ;

[0020] S23. Randomly select a group within the salinity range [S L S U At experimental point i within the range, the solubility ratio σ of the oil phase and the aqueous phase was obtained. io测 and σ iw测 ;

[0021] S24. Solve for the sum of squared residuals R ss :

[0022]

[0023] S25. Let B = B0 + ΔB, and repeat steps S22 and S24 if and only if B > B0. max When the loop ends, the smallest residual sum of squares R in the set of all solution residual sums obtained at this point is... ssmin The corresponding B value is the final B value obtained from the solution. fin ;

[0024] S3, B fin Substituting the values ​​into the following formula, we can calculate the theoretical upper and lower bounds of the HLD value. L算 HLD U算 :

[0025]

[0026]

[0027] In the formula, σ * The optimal solubilization ratio corresponding to the optimal salinity was determined through experiments on the phase behavior of microemulsions; N a Here is Avogadro's constant, with a value of 6.023 × 10⁻⁶. 23 V s The volume of the surfactant is in cm. 3 V om V is the volume of the oil phase dissolved in the microemulsion obtained in the experiment. om测 V wm V is the volume of the aqueous phase dissolved in the microemulsion obtained in the experiment. wm测 ;

[0028] S4, according to HLD L算 and HLD U算 Determine the microemulsion phase corresponding to the hydrophilicity-lipophilicity deviation value (HLD) for different salinities.

[0029] The method for determining the phase state of microemulsions is as follows:

[0030] First, determine whether each hydrophilicity / lipophilicity deviation value belongs to HLD. L算 and HLD U算 The range of composition [HLD] L算 HLD U算If the HLD is within the range of 0, then the emulsion corresponding to the HLD is determined to be a Winsor III type microemulsion; if not, then it is determined whether the HLD is greater than 0. If the HLD is less than 0, then the emulsion corresponding to the HLD is determined to be a Winsor I type microemulsion; if the HLD is greater than 0, then the emulsion corresponding to the HLD is determined to be a Winsor II type microemulsion.

[0031] S5. Calculate the volume V of the oil phase dissolved in the microemulsion phase for each of the Winsor I, Winsor II, and Winsor III microemulsions. om and water phase volume V wm And the solubility ratio σ between the oil phase and the aqueous phase om σ wm According to the calculated V om V wm σ om σ wm The fitted phase transition curves were plotted. The accuracy was adjusted for the phase transition positions, and finally, an HLD-NAC model flowchart was generated to guide the rapid construction of microemulsion surfactant composite systems.

[0032] For each type of microemulsion, the solubilization ratio σ between the oil phase and the aqueous phase is first calculated. om σ wm Then, the volume V of the oil phase dissolved in the microemulsion is calculated using the following formula. om and water phase volume V wm :

[0033]

[0034]

[0035] V om =σ im ×V s

[0036] V wm =σ wm ×V a

[0037] In the formula, V s The volume of the surfactant is in cm. 3 .

[0038] Method for adjusting accuracy: Determine whether the errors between the theoretical and experimental values ​​of the oil phase solubility ratio and the water phase solubility ratio are both controlled within 10%. If so, the accuracy meets the requirements; if not, adjust the B value and remove the smallest residual sum of squares R from the set of all solution residual sums obtained in step S25. ssmin Then select the minimum residual sum of squares R in the new set. ssmin1The corresponding B value is used as the final B value. fin1 Then repeat S3-S5 until the accuracy meets the requirements, that is, the error between the theoretical calculation value and the experimental value of the solubility ratio of the oil phase and the solubility ratio of the water phase is controlled within 10%.

[0039] Compared with the prior art, the advantages of the present invention are:

[0040] (1) The method of the present invention can be extended to the prediction of phase behavior of microemulsion system after the indoor phase behavior data is measured, and at the same time obtains the quantitative solubilization ratio and the volume of the solubilized oil phase / water phase.

[0041] (2) High processing efficiency. The phase transition prediction process requires little experimental work, and the phase transition curve can be generated through 5 sets of experimental test data.

[0042] (3) High operational accuracy. High-precision prediction can be achieved by combining Python programming software to select the smallest sum of squared residuals.

[0043] (4) Wide applicability. The unknown quantity calculation method proposed in this invention can be applied not only to mature commercial surfactants, but also to surfactant systems with unknown parameters.

[0044] (5) Low time cost. It significantly reduces the number of microemulsion system preparations and salinity scanning test groups in the laboratory, and the predicted HLD window of the middle phase microemulsion has theoretical guiding significance.

[0045] (6) The modified model can provide theoretical guidance for the application of surfactant systems in microemulsions of different types of reservoirs. This method has practical significance for the screening and construction of surfactant complex systems that form microemulsions.

[0046] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0047] Figure 1 A flowchart of the rapid construction method of the microemulsion surfactant composite system provided by the present invention.

[0048] Figure 2 A comparison chart of the theoretical phase transition curves and experimental measurements obtained by this invention. Detailed Implementation

[0049] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0050] Figure 1 This is a flowchart of a rapid construction method for a microemulsion surfactant composite system provided by the present invention. The rapid construction method for the microemulsion surfactant composite system of the present invention is derived from the following theoretical derivation process.

[0051] Model Assumptions: The general assumptions in the NAC algorithm are as follows:

[0052] (1) Microemulsions can be represented as imaginary spherical droplets in which oil and water coexist;

[0053] (2) The concentration of surfactants in monomeric form can be ignored;

[0054] (3) The molar concentration of the surfactant is calculated by assuming the surfactant density is 1 g / ml;

[0055] (4) The surface area of ​​the surfactant head is constant under different salinity and temperature.

[0056] The rapid construction and design process of a microemulsion surfactant composite system (taking a combination of two surfactants as an example) is as follows:

[0057] Step S1: Determine the primary surfactant and co-surfactant, and conduct laboratory microemulsion phase behavior experiments. Obtain the optimal salinity S* through salinity scanning experiments.

[0058] The empirical formula for the hydrophilicity-lipophilicity deviation value (HLD) is as follows:

[0059] HLD=Ln(S)-K mix ×EACN+C cmix -α T ×ΔT-f(A) (1)

[0060] Ln(S * ) = K mix ×EACN-C Cmix +α T ×ΔT+f(A) (2)

[0061]

[0062] Combining formulas (1) and (2), we obtain formula (3), and use formula (3) to quickly solve the hydrophilic-lipophilic deviation value (HLD) corresponding to different salinities.

[0063] In the formula: S is salinity, NaCl g / 100mL; S* is the optimal salinity, obtained through a salinity scanning experiment, at which point the corresponding HLD value is 0, NaCl g / 100mL; EACN is the equivalent alkane carbon number in the oil phase; K is the slope of the curve relating the logarithm of the optimal salinity to the alkane carbon number (K1 and K2 are the molar weighted K values ​​of the main surfactant and co-surfactant, respectively, K...mix K is the K value after compounding. mix =x1K1+x2K2); C C The characteristic parameters of surfactants, whose molar weighting rules are similar to those for K values, C cmix =x1C C1 +x2C C2 ;α T ΔT is the temperature coefficient at the optimal salinity, typically 0.01 for ionic surfactants, in units of LnS / ℃; ΔT is the difference between the experimental temperature and the reference temperature, which is 25℃, in units of ℃; f(A) is a function of the type and concentration of the alcohol, determined based on the co-surfactant; x1 and x2 are the weights of the primary surfactant and the co-surfactant.

[0064] According to the NAC equation of state, the net curvature of the surfactant interface and the average curvature of the microemulsion are:

[0065]

[0066]

[0067] In the formula, H n Net curvature of the surfactant interface. H a The mean curvature of the microemulsion. R o R w Let the radii of the assumed oil and water phases be spherical. L is the full extension length of the tail group of the surfactant.

[0068] For the oil / aqueous phase spherical radii (i = o, w) of Winsor I and Winsor II microemulsions:

[0069]

[0070] In the formula, V i Let i be the volume of component i dissolved in the microemulsion, in cm. 3 A S This represents the interfacial area occupied by surfactant molecules at the interface.

[0071] The total area occupied by each surfactant molecule:

[0072] A S =N a ×n S ×a S (7)

[0073] In the formula, N aHere is Avogadro's constant, with a value of 6.023 × 10⁻⁶. 23 ;n S The mole number of the surfactant; a S This represents the surface area of ​​a single surfactant molecule.

[0074] The maximum characteristic length of a surfactant is related to the optimal solubility ratio σ. * Related:

[0075]

[0076] In the formula, The maximum characteristic length of the surfactant represents the maximum solubilizing capacity of the microemulsion. σ * The optimal solubilization ratio corresponding to the optimal salinity obtained from laboratory phase behavior experiments; M W denoted as the molecular weight of the surfactant, in g / mol.

[0077] When calculating the volume of the oil / water phase dissolved in the microemulsion phase and the solubilization ratio of Winsor type I, II, and III microemulsions, for Winsor type I and II microemulsions, the volume of the oil / water phase dissolved in the microemulsion phase is (j = o or w):

[0078]

[0079] In the formula, V im Let i be the volume of component i dissolved in the microemulsion, in cm. 3 V j For the volume of another component different from component i, cm 3 .

[0080] For Winsor III type microemulsions, the system exists in a state where excess aqueous phase, excess oil phase, and microemulsion phase coexist, so R cannot be directly determined. o or R w Because the volume of oil or water dissolved in the microemulsion phase is unknown. At this point, the oil phase V dissolved in the microemulsion phase... om or aqueous phase V wm Volume:

[0081]

[0082]

[0083] Meanwhile, through conversion, when HLD=0, the region width of the Winsor III microemulsion and its upper and lower boundaries can be obtained:

[0084]

[0085]

[0086]

[0087] In the formula, V s The volume of the surfactant is in cm. 3 .

[0088] The calculation formulas (4)-(14) above involve a large amount of computation and many unknowns, such as L and a. S M w In previous studies, single surfactant systems were often fitted using methods such as stepwise regression. However, this approach is labor-intensive and requires repeated confirmation with multiple sets of preliminary experimental data. However, for the composite surfactants of this invention, L and a... S M w All three parameters are unknown, and their specific values ​​cannot be determined.

[0089] To address the aforementioned technical problems, the present invention includes step S2.

[0090] Step S2: A new parameter B is defined and solved. Let... At this point, the formula for calculating the solubility ratio of the oil phase and the aqueous phase becomes as follows:

[0091]

[0092]

[0093] The solution process for parameter B can be found in [link to solution]. Figure 1 The final solution for the B value B is obtained from the middle II plate. fin B fin Used for subsequent calculation steps.

[0094] Step S3, B fin Substituting the values ​​into the following formula, we can calculate the theoretical upper and lower bounds of the HLD value. L算 HLD U算 :

[0095]

[0096]

[0097] Step S4, according to HLD L算 and HLD U算 Determine the microemulsion phase corresponding to the hydrophilicity-lipophilicity deviation value (HLD) for different salinities.

[0098] Step S5: Calculate the volume V of the oil phase dissolved in the microemulsion phase for Winsor type I, Winsor type II, and Winsor type III microemulsions, respectively. om and water phase volume V wm And the solubility ratio σ between the oil phase and the aqueous phase om σ wm According to the calculated V om V wm σ om σ wm The fitted phase transition curves were plotted. The accuracy was adjusted for the phase transition positions, and finally, an HLD-NAC model flowchart was generated to guide the rapid construction of microemulsion surfactant composite systems.

[0099] Example

[0100] In this embodiment, KPS (potassium persulfate) and APS (sodium persulfate) are used as surfactants to form a surfactant composite system. The construction steps of the microemulsion surfactant composite system are as follows:

[0101] 1. The indoor microemulsion phase experiment used equipment including a balance, pipettes, alcohol burner, and test tube mixer. The oil used was tetradecane, with a viscosity of 1.1 mPa·s at 44℃. The water used was deionized water. The surfactant systems forming the microemulsions were KPS and APS. Both KPS and APS solutions were dissolved in deionized water at a mass fraction of 0.4 wt%, forming surfactant aqueous solutions. The salinity of the surfactant aqueous solutions was varied (1.5–8 wt.%) by adjusting the sodium chloride (NaCl) concentration. The surfactant concentration remained the same for all salinity systems, resulting in surfactant aqueous solutions with different salinities. At the experimental temperature (44℃), the surfactant aqueous solutions with different salinities were first aged. Within 14 days, no significant changes were observed in density, viscosity, pH value, or appearance, indicating that the surfactant system has high aging stability.

[0102] The microemulsion salinity scanning experiment procedure was as follows: An equal volume of surfactant aqueous solution and tetradecane was added to a screw-top test tube. The test tube was sealed and inverted until the oil and water were fully mixed. The test tube was placed in a 44℃ oven and allowed to stand for 14 days, with the tube being shaken daily for 7 days. After 14 days, the oil and water phases reached equilibrium. The test tube was then removed, and the phase type, phase volume, and appearance of the aqueous phase were recorded to evaluate the solubilizing and emulsifying properties of the percolating liquid. The above experiment was conducted using surfactant aqueous solutions with different salinities.

[0103] 2. Based on laboratory phase behavior experiments, eight sets of data (S) were tested to determine the formation of mesophase microemulsions. * S L S UThe experimental values ​​corresponding to S1, S2, S3, S4, and S5, as well as the data from two groups each of Winsor type I microemulsions and Winsor type II microemulsions (S... I1 S I2 S II1 S II2 Substitute the data into the subsequent calculation steps. The experimental test values ​​and calculated values ​​are shown in Table 1 below.

[0104] Table 1 Experimental Data

[0105]

[0106]

[0107] Finally, B = 7.67 was obtained, corresponding to HLD. L算 = -0.2467; HLD U算 =0.2495.

[0108] The solubilization volume and solubilization ratio of the oil / water phase corresponding to the 12 experimental points are shown in Table 2 below.

[0109] Table 2. Oil / Aqueous Phase Solubilization Volume and Solubilization Ratio for 12 Experimental Groups

[0110]

[0111] Draw the phase transition curves according to Table 2, see... Figure 2 . Figure 2 This demonstrates that the phase transition curve constructed by the method of this invention ( Figure 2 The theoretical aqueous phase solubility ratio and theoretical oil phase solubility ratio in the model have high fitting accuracy with the phase behavior data in the laboratory, which can provide guidance for the prediction of microemulsion phase behavior and the rapid construction of surfactant composite systems.

[0112] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A rapid construction method for a microemulsion surfactant composite system, characterized in that, The steps are as follows: S1. Determine the types of surfactants in the surfactant composite system and conduct laboratory microemulsion phase behavior experiments; obtain the optimal salinity S through salinity scanning experiments. * Calculate the hydrophilic-lipophilic deviation value (HLD) corresponding to different salinities S, and preliminarily determine the salinity range [S] of the mid-phase microemulsion based on the phase transition point. L S U And the upper and lower bounds of the HLD value HLD L测 HLD U测 Determine the volume V of the solubilized aqueous phase corresponding to the lower boundary of HLD. wm测 The volume V of the solubilized oil phase corresponding to the upper boundary of HLD om测 ; S2. Define a parameter B, let... In the formula, M W a is the molecular weight of the surfactant, in g / mol; S The surface area of ​​a single surfactant molecule. L is the full extension length of the tail group of the surfactant. Due to L, a S M w The three parameters are unknown; therefore, the following method is used to solve for the value of B: S21. Calculate the upper and lower bounds of HLD. L测 HLD U测 The corresponding B value, B L and B U And solve for B corresponding to each experimental test point. X The value of X is 1, 2, 3, ..., X, where X ≥ 5; the calculation formula is as follows: In the formula, σ * The optimal solubilization ratio corresponding to the optimal salinity was determined through experiments on the phase behavior of microemulsions; N a Here is Avogadro's constant, with a value of 6.023 × 10⁻⁶. 23 V s The volume of the surfactant is in cm. 3 V om V is the volume of the oil phase dissolved in the microemulsion obtained in the experiment. om测 V wm V is the volume of the aqueous phase dissolved in the microemulsion obtained in the experiment. wm测 ; S22. Let the initial value be B0 = B min Let the step size ΔB = 0.01 × (B max -B min ); B min For B X B L B U The minimum value in; B max For B X B L B U The maximum value in the range; substitute the B0 value into the following formula to calculate the solubilization ratio σ. io算 and σ iw算 ; In the formula, σ * The optimal solubilization ratio corresponding to the optimal salinity was determined through experiments on the phase behavior of microemulsions; N a Here is Avogadro's constant, with a value of 6.023 × 10⁻⁶. 23 ; S23. Randomly select a group within the salinity range [S L S U At experimental point i within the range, the solubility ratio σ of the oil phase and the aqueous phase was obtained. io测 and σ iw测 ; S24. Solve for the sum of squared residuals R ss : S25. Let B = B0 + ΔB, and repeat steps S22 and S24 if and only if B > B0. max When the loop ends, the smallest residual sum of squares R in the set of all solution residual sums obtained at this point is... ssmin The corresponding B value is the final B value obtained from the solution. fin ; S3, B fin Substituting the values ​​into the following formula, we can calculate the theoretical upper and lower bounds of the HLD value. L算 HLD U算 : In the formula, σ * The optimal solubilization ratio corresponding to the optimal salinity was determined through experiments on the phase behavior of microemulsions; N a Here is Avogadro's constant, with a value of 6.023 × 10⁻⁶. 23 V s The volume of the surfactant is in cm. 3 V om V is the volume of the oil phase dissolved in the microemulsion obtained in the experiment. om测 V wm V is the volume of the aqueous phase dissolved in the microemulsion obtained in the experiment. wm测 ; S4, according to HLD L算 and HLD U算 Determine the microemulsion phase corresponding to the hydrophilicity-lipophilicity deviation value (HLD) for different salinities; S5. Calculate the volume V of the oil phase dissolved in each microemulsion phase. om and water phase volume V wm And the solubility ratio σ between the oil phase and the aqueous phase om σ wm The fitted phase transition curves are plotted, and the accuracy is adjusted for the phase transition positions. Finally, the HLD-NAC model flowchart is generated to guide the rapid construction of microemulsion surfactant composite systems.

2. The rapid construction method of the microemulsion surfactant composite system as described in claim 1, characterized in that, In step S4, the method for determining the phase state of the microemulsion is as follows: First, determine whether each hydrophilicity / lipophilicity deviation value belongs to HLD. L算 and HLD U算 The range of composition [HLD] L算 HLD U算 If the HLD is within the range of 0, then the emulsion corresponding to the HLD is determined to be a Winsor III type microemulsion; if not, then check if the HLD is greater than 0. If the HLD is less than 0, then the emulsion corresponding to the HLD is determined to be a Winsor I type microemulsion; if the HLD is greater than 0, then the emulsion corresponding to the HLD is determined to be a Winsor II type microemulsion.

3. The rapid construction method of the microemulsion surfactant composite system as described in claim 2, characterized in that, In step S5, the volume V of the oil phase dissolved in the microemulsion phase of Winsor type I microemulsion, Winsor type II microemulsion, and Winsor type III microemulsion is calculated respectively. om and water phase volume V wm And the solubility ratio σ between the oil phase and the aqueous phase om σ wm According to the calculated V om V wm σ om σ wm Plot the fitted phase transition curve.

4. The rapid construction method of the microemulsion surfactant composite system as described in claim 3, characterized in that, In step S5, the solubility ratio σ between the oil phase and the aqueous phase is first calculated. om σ wm Then, the volume V of the oil phase dissolved in the microemulsion is calculated using the following formula. om and water phase volume V wm : V om =s om ×V s V wm =s wm ×V s In the formula, V s The volume of the surfactant is in cm. 3 .

5. The rapid construction method of the microemulsion surfactant composite system as described in claim 3, characterized in that, In step S5, it is determined whether the errors between the theoretical and experimental values ​​of the oil phase solubility ratio and the water phase solubility ratio are both controlled within 10%. If so, the accuracy meets the requirements; if not, the value of B is adjusted, and the smallest residual sum of squares R is removed from the set of all solution residual sums of squares obtained in step S25. ssmin Then select the minimum residual sum of squares R in the new set. ssmin1 The corresponding B value is used as the final B value. fin1 Then repeat S3-S5 until the error between the theoretical and experimental values ​​of the solubility ratio of the oil phase and the solubility ratio of the water phase is controlled within 10%.

6. The rapid construction method of the microemulsion surfactant composite system as described in claim 1, characterized in that, In step S1, the formula for calculating the hydrophilicity-lipophilicity deviation value (HLD) corresponding to different salinities S is as follows: In the formula, S is the salinity, NaCl g / 100mL; S* is the optimal salinity, corresponding to an HLD value of 0, NaCl g / 100mL.

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