A shale multi-mineral chemical kinetics reaction rate differential weight analysis method

Abstract

The present application relates to a kind of shale multi-mineral chemical kinetics reaction rate differential heavy analysis method, belong to the technical field of oil and gas reservoir reconstruction acidification reaction kinetics research.The reaction process of carbonate rock and hydrofluoric acid in shale is separated out by defining a new variable-acid rock reaction rate ratio, and the acid rock reaction rate of siliceous mineral in shale is calculated using the weight loss relationship of carbonate rock mineral and siliceous mineral in shale.Compared with the conventional acid rock reaction rate calculation method that all minerals are regarded as a whole, this acid rock reaction kinetics research method of separately calculating carbonate rock mineral and siliceous mineral in shale has higher accuracy and reasonableness.

Description

Technical Field

[0001] The invention relates to a shale multi-mineral chemical kinetic reaction rate differential gravity analysis method, belonging to the technical field of oil and gas field reservoir transformation acidification reaction kinetics research. Background Art

[0002] Shale oil and gas is a type of unconventional resource with huge potential. Due to its own physical property limitations, shale reservoirs are difficult to form industrial production under natural conditions. Therefore, the production capacity of shale reservoirs is greatly affected by the effectiveness of reservoir transformation technology.

[0003] Compared to traditional hydraulic fracturing reservoir stimulation technology, acid fracturing offers significant advantages for improving permeability, reducing the difficulty of initiating fractures in deep shale layers, facilitating the formation of complex fracture networks, and effectively supporting the reservoir without the need for proppants. Acid fracturing is a promising shale reservoir stimulation process. Acid fracturing involves injecting acidic fluid into the reservoir, increasing the permeability of the rock through chemical reactions between the acid and the reservoir rock, and improving oil and gas production efficiency. In shale reservoirs, acidification primarily dissolves inorganic minerals and removes blockages in natural fractures, thereby increasing the effective width of the fractures and permeability pathways, optimizing gas flow conditions. The positive impact of shale acid fracturing on the field is reflected in improved recoverability and economic development benefits of shale oil and gas. Effective acid fracturing can significantly increase oil and gas production and recovery rates, reduce development costs, and improve the overall development efficiency of oil and gas fields.

[0004] The study of acid-rock reaction kinetics is the cornerstone of acidizing design. A precise understanding of the kinetics of acid-rock reactions provides a scientific basis for acidizing process design, including the optimization of key parameters such as acid type, concentration, and injection rate. This not only improves acidizing effectiveness but also reduces unnecessary resource and environmental risks. Reaction rate is a fundamental parameter in acid-rock reaction kinetics research. However, due to the extremely complex mineral composition of shale (including siliceous minerals, carbonate minerals, and metallic minerals), determining the reaction rates of different mineral types in shale is a pressing challenge in shale acid-rock reaction kinetics research.

[0005] Due to the differences in the reaction equations of carbonate rocks and siliceous minerals, the reaction kinetic behavior of shale cannot be simply characterized by substituting the overall reaction rate of shale into the reaction equations of carbonate rocks or siliceous minerals during the research process. Instead, the reaction rates of carbonate rocks and siliceous minerals should be obtained separately, and their reaction kinetic equations should be solved step by step, and then the results should be obtained through comprehensive consideration.

[0006] There is no generally accepted unified solution method at present. The most widely used method is to first use hydrochloric acid to dissolve the carbonate rock in the shale and then use hydrofluoric acid to dissolve the siliceous minerals in the shale. However, this method is not only difficult to obtain the actual reaction rate of hydrofluoric acid and carbonate rock when hydrofluoric acid dissolves shale in actual conditions, but also the secondary hydrofluoric acid treatment of shale that has been treated with hydrochloric acid and has a changed pore structure will obviously cause a large error. As shown in the method of a kind of acid rock reaction rate prediction device and method disclosed in Chinese patent document CN117054284A, the acid rock reaction rate test method provided therein adopts a calculation method that uses the overall weight loss of core minerals before and after acidification as an evaluation index. Such a method cannot derive the individual reaction rates of different minerals in the core. Therefore, there is an urgent need for a method that can test the individual reaction rates of different minerals in rocks with complex mineral components such as shale to promote the improvement of theoretical analysis accuracy in the field of shale acidification. Summary of the Invention

[0007] In response to the shortcomings of the existing technology, the present invention provides a differential gravimetric analysis method for the chemical kinetic reaction rates of multiple minerals in shale. By setting up different acidizing experimental schemes with hydrochloric acid, hydrofluoric acid, shale, and carbonate rock, the acid-rock reaction rates of carbonate rock minerals and siliceous minerals in shale under real formation acidizing conditions (without the influence of prior hydrochloric acid modification) are obtained.

[0008] The technical solutions of the present invention are as follows:

[0009] A shale multi-mineral chemical kinetic reaction rate differential gravimetric analysis method comprises the following steps:

[0010] (1) Through the rotating rock plate experiment, the weight loss of carbonate rock core and hydrochloric acid acidification reaction under fixed experimental conditions was obtained;

[0011] (2) Through the rotating rock plate experiment, the acid concentration is controlled to be the same as the acid concentration in step (1), and the weight loss of the shale core and hydrochloric acid acidification reaction under fixed experimental conditions is obtained;

[0012] (3) Calculate the acid-rock reaction rates of hydrochloric acid reacting with carbonate rock core and shale core, respectively, and thereby calculate the acid-rock reaction rate ratios of hydrochloric acid reacting with carbonate rock core and shale core, respectively;

[0013] (4) Through the rock rotating experiment, the acid concentration is controlled to be the same as the acid concentration in step (1), and the weight loss of the carbonate rock core and the hydrofluoric acid acidizing reaction under fixed experimental conditions is obtained;

[0014] (5) Calculate the acid-rock reaction rate of the carbonate rock core and hydrofluoric acid acidization reaction using the method in step (3) k HF-CA ;

[0015] (6) Acidification reaction rate of carbonate rock core with hydrofluoric acid k HF-CA Acid-rock reaction rate ratio K CA-SH Estimating the acid-rock reaction rate between carbonate minerals in shale and hydrofluoric acid k HF-CA-SH ;

[0016] (7) The acid-rock reaction rate between carbonate minerals in shale and hydrofluoric acid k HF-CA-SH Calculate the weight loss Δ of carbonate minerals in shale m HF-CA-SH ;

[0017] (8) Through the rotating rock plate experiment, the acid concentration is controlled to be the same as the acid concentration in step (1), and the weight loss Δ of the shale core and hydrofluoric acid acidizing reaction under fixed experimental conditions is obtained. m HF-SH ;

[0018] (9) By comparing with Δ m HF-CA-SH Perform difference calculation to obtain the weight loss Δ of the siliceous minerals in the shale core due to the acidification reaction with hydrofluoric acid under fixed experimental conditions. m HF-SI-SH ;

[0019] (10) Calculate the acid-rock reaction rate of the shale core and hydrofluoric acid acidizing reaction using the method in step (3) k HF-SI-SH , so far, the acid-rock reaction rates of carbonate minerals and siliceous minerals in shale are obtained.

[0020] Preferably, in step (1) of the present invention, the rotating rock disc experiment step is to seal the cut core into a rubber sleeve and fix it on the rotating handle of the rotating rock disc, leaving only the end face of the core to react with the acid solution. The core in the rotating rock disc reactor rotates with the acid solution. After the set time is reached, the core is taken out, dried and weighed to obtain the weight loss of the carbonate rock core in the acidification reaction with hydrochloric acid.

[0021] According to the preferred embodiment of the present invention, in step (1), the core is a columnar piece with a bottom diameter of 2.5 cm and a height of 3 cm, which is a standard size core. The weight loss is measured with an accuracy of 0.001 g. After acidification, the surface is rinsed and dried at 100°C for 24 hours.

[0022] According to a preferred embodiment of the present invention, in the reaction in step (2), since most of the hydrochloric acid reacts only with the carbonate minerals in the shale, the weight loss of the hydrochloric acid reacting with the shale core equals the weight loss of the hydrochloric acid reacting with the carbonate minerals in the shale.

[0023] According to the preferred embodiment of the present invention, in step (2), the core is a standard size core with a bottom diameter of 2.5 cm and a height of 3 cm, and the weight loss is weighed with an accuracy of 0.001 g. After acidification, the surface is rinsed and dried at 100°C for 24 hours.

[0024] According to the preferred embodiment of the present invention, in step (3), the acid-rock reaction rate is calculated using formula (1):

[0025] (1)

[0026] in, k acid-rock The acid-rock reaction rate of a specific acid solution and a specific rock, in mol / (cm 2 ·s); Δ m R is the weight loss of rock before and after acidification, in g; M R is the molar mass of the rock, in g / mol; Δ t is the acid-rock reaction time, in seconds; S is the contact area of ​​the acidification reaction, in cm 2 ; n r is the stoichiometric coefficient of the acid-rock reaction. When the reactant is carbonate rock, n r is 2;

[0027] Ratio of acid-rock reaction rate of hydrochloric acid to carbonate rock core k HCl-CA and the acid-rock reaction rate of shale core and hydrochloric acid k HCl-SH Ratio K CA-SH The expression is shown in formula (2):

[0028] (2)

[0029] According to the preferred embodiment of the present invention, in step (2), the core is a standard size core with a bottom diameter of 2.5 cm and a height of 3 cm, and the weight loss is weighed with an accuracy of 0.001 g. After acidification, the surface is rinsed and dried at 100°C for 24 hours. The shale bedding is parallel to the axial direction of the core cylinder to achieve a more significant acidizing effect. The acid can be a type of acid that can dissolve siliceous minerals, such as hydrofluoric acid or mud acid.

[0030] According to the present invention, preferably, in step (6), k HF-CA-SH Use formula (3) to calculate:

[0031] (3)

[0032] The acid-rock reaction rate between carbonate minerals and hydrofluoric acid in shale under the conditions of shale pore fracture structure is obtained by calculation using formula (3);

[0033] The acidizing reaction rate of carbonate rock core with hydrofluoric acid k HF-CA divided by the acid-rock reaction rate ratio K CA-SH The principle of obtaining the acidification reaction rate of carbonate rock minerals with hydrofluoric acid in shale cores is that according to the Arrhenius theorem, the acid-rock reaction rate formula within a certain temperature range under constant pressure can be written as formula (4):

[0034] (4)

[0035] in, k acid-rock is the acid-rock reaction rate, mol / (cm 2 s); A It refers to the pre-factor or frequency factor, which is related to the type of reactants, the frequency of molecular collisions and the direction of the reaction, mol / (cm 2 s); E a is the activation energy, i.e., the energy barrier that needs to be overcome to proceed with the reaction, J / mol; R is the ideal gas constant, 8.314 J / (mol·K); T is the reaction temperature, K; exp represents the exponential function of the base e of the natural logarithm.

[0036] In the reaction process of carbonate rock with hydrochloric acid and hydrofluoric acid respectively, due to the constant pressure, constant molar gas constant, the same temperature and the same reactants, the corresponding activation energy is equal, that is,

[0037] （E a ） HF-CA =（E a ） HF-CA-SH (5)

[0038] （E a ） HCL-CA =（E a ） HCL-CA-SH (6)

[0039] Where, （E a ）HF-CA is the activation energy of the reaction between hydrofluoric acid and carbonate rock, in kJ / mol; （E a ） HF-CA-SH is the activation energy of the reaction between hydrofluoric acid and carbonate minerals in shale, in kJ / mol; （E a ） HCL-CA is the activation energy of the reaction between hydrochloric acid and carbonate rock, in kJ / mol; （E a ） HCL-CA-SH is the activation energy of the reaction between hydrochloric acid and carbonate minerals in shale, in kJ / mol;

[0040] And according to the principle of acid-rock reaction kinetics, the pre-exponential factor A The expression can be written as shown in formula (7):

[0041] (7)

[0042] Where, A 0 is the reaction rate constant under certain temperature, pressure, reaction contact area, specific surface area of ​​porous medium, acid concentration, and reactant type, in m / s; a v is the specific surface area of ​​porous media per unit volume, in m 2 / m 3 ; C s is the acid concentration in mol / L.

[0043] For carbonate cores that are not acidified and are taken from the same original rock, there are ( a v ) HCl-CA =( a v ) HF-CA ;

[0044] Where, ( a v ) HCl-CA is the specific surface area of ​​the reaction between hydrochloric acid and carbonate rock, in m 2 / m 3 ;( a v ) HF-CA is the specific surface area of ​​the reaction between hydrofluoric acid and carbonate rock, in m 2 / m 3 .

[0045] Similarly, for shale cores taken from the same original stone, there are (a v ) HCl-CA-SH =( a v ) HF-CA-SH ;

[0046] Where, ( a v ) HCl-CA-SH is the specific surface area of ​​the reaction between hydrochloric acid and carbonate minerals in shale, in m 2 / m 3 ;( a v ) HF-CA-SH is the specific surface area of ​​the reaction between hydrofluoric acid and carbonate minerals in shale, in m 2 / m 3 .

[0047] so Established;

[0048] Because the acid concentration, pressure and temperature are the same in different acidification experiments, there is ;

[0049] Where, A HCL-CA is the pre-exponential factor of the reaction between hydrochloric acid and carbonate rock, in mol / (cm 2 s); A HF-CA is the pre-exponential factor of the reaction between hydrofluoric acid and carbonate rock, in mol / (cm 2 s); A HCL-CA-SH is the pre-exponential factor of the reaction between hydrochloric acid and carbonate minerals in shale, in mol / (cm 2 s); A HF-CA-SH is the pre-exponential factor of the reaction between hydrofluoric acid and carbonate minerals in shale, in mol / (cm 2 s);

[0050] Therefore, we have formula (8):

[0051] (8)

[0052] Therefore Established.

[0053] According to the preferred embodiment of the present invention, the weight loss Δ of the carbonate minerals in the shale in step (7) is m HF-CA-SH The calculation formula is shown in formula (9):

[0054] (9)

[0055] Where, k HF-CA-SH is the acid-rock reaction rate between carbonate minerals in shale and hydrofluoric acid; M R is the molar mass of the rock, in g / mol; Δ t is the acid-rock reaction time, in seconds; S is the contact area of ​​the acidification reaction, in cm 2 ; n r is the stoichiometric coefficient of the acid-rock reaction. When the reactant is carbonate rock, n r is 2;

[0056] According to the preferred embodiment of the present invention, in step (8), the acid solution may be hydrofluoric acid, mud acid or other acid type that can dissolve siliceous minerals.

[0057] According to the preferred embodiment of the present invention, in step (8), the core is a standard size core with a bottom diameter of 2.5 cm and a height of 3 cm, and the weight loss is measured with an accuracy of 0.001 g. After acidification, the surface is rinsed and dried at 100°C for 24 hours.

[0058] According to the present invention, preferably, in step (9), when hydrofluoric acid is used for acidification, carbonate minerals and siliceous minerals in the shale participate in the reaction at the same time, so the total weight loss after acidification Δ m HF-SH =Δ m HF-SI-SH +Δ m HF-CA-SH , so, Δ m HF-SI-SH =Δ m HF-SH -Δ m HF-CA-SH .

[0059] The beneficial effects of the present invention are:

[0060] 1. The present invention defines a new variable - acid-rock reaction rate ratio K HF-HCl In this way, the reaction process of carbonate rock and hydrofluoric acid in shale was separated separately, and the acid-rock reaction rate of siliceous minerals in shale was calculated by using the weight loss relationship between carbonate rock minerals and siliceous minerals in shale. Compared with the conventional acid-rock reaction rate calculation method that regards all minerals as a whole, this research method of calculating the acid-rock reaction kinetics of carbonate rock minerals and siliceous minerals in shale separately has higher accuracy and rationality.

[0061] 2. The present invention provides a process flow for calculating the kinetic parameters of shale acid-rock reaction. By rationally setting up acidizing experimental combinations of different acid solutions and rocks, the acidizing weight loss and acid-rock reaction rate of shale under the action of different acid solutions can be calculated, thereby promoting the advancement of shale reservoir acidizing transformation theory and the improvement of on-site acidizing technology in shale oil and gas field production areas.

[0062] 3. The present invention proposes a shale multi-mineral chemical kinetic reaction rate differential analysis method, which can obtain the reaction rates of carbonate minerals and siliceous minerals in shale separately without changing the shale reaction specific surface area, porosity, and permeability (i.e., eliminating the errors caused by multiple acidizing). This improves the accuracy of shale acidizing numerical simulation parameters, promotes the improvement of shale acidizing schemes on oil field sites, and further enhances the shale reservoir transformation effect, reducing the cost burden caused by mismatched acidizing parameters during shale oil and gas production. DETAILED DESCRIPTION

[0063] The present invention will be further described below by way of examples, but is not limited thereto.

[0064] Example 1:

[0065] This embodiment provides a method for differential gravimetric analysis of chemical kinetic reaction rates of multiple minerals in shale, including the following steps:

[0066] (1) Through the rotating rock plate experiment, the weight loss of carbonate rock core and hydrochloric acid acidification reaction under fixed experimental conditions was obtained;

[0067] The specific steps are as follows: the cut core is sealed in a rubber sleeve. The core is a standard size core with a bottom diameter of 2.5 cm and a height of 3 cm. The core is fixed on the rotating handle of the rotating rock plate, leaving only the end face of the core to react with the acid solution. After acidification, the surface is rinsed and dried at 100°C for 24 hours. The acid concentration used is 4% by mass, the temperature is 60°C (common formation temperature), and the acid-rock reaction time is 2 minutes. The core and the acid solution in the rotating rock plate reactor rotate. After the set time is reached, the core is taken out, dried and weighed. The weight loss is measured with an accuracy of 0.001g. The weight loss Δ of the carbonate core in the hydrochloric acid acidification reaction is obtained. m HCl-CA =0.857g;

[0068] (2) Through the rotating rock plate experiment, the acid concentration is controlled to be the same as the acid concentration in step (1), and the weight loss Δ of the shale core and hydrochloric acid acidification reaction under fixed experimental conditions is obtained. m HCl-SH =9.236 g, weight loss of hydrochloric acid reacting with shale core Δ m HCl-SH = Weight loss from the reaction of hydrochloric acid with carbonate minerals in shale Δ m HCl-CA-SH;

[0069] (3) Calculate the acid-rock reaction rate of hydrochloric acid reacting with carbonate rock core and shale core respectively k HCl-CA and k HCl-SH , and calculate the acid-rock reaction rate ratio of hydrochloric acid reacting with carbonate rock core and shale core respectively;

[0070] The acid-rock reaction rate can be calculated as follows:

[0071]

[0072]

[0073] The ratio of the acid-rock reaction rate of hydrochloric acid reacting with carbonate rock core and shale core respectively K CA-SH The calculation formula is:

[0074]

[0075] (4) Through the rotating rock plate experiment, the acid concentration is controlled to be the same as the acid concentration in step (1), and the weight loss Δ of the carbonate rock core and hydrofluoric acid acidization reaction under fixed experimental conditions is obtained. m HF-CA =0.0766 g;

[0076] In the bedrock experiments, standard cores were used, with a base diameter of 2.5 cm and a height of 3 cm. Weight loss was measured to an accuracy of 0.001 g. After acidification, the surface was rinsed and dried at 100°C for 24 hours. The acid concentration used was 4% by mass, and the temperature was 60°C (common formation temperature). The acid-rock reaction time was 24 hours.

[0077] (5) Calculate the acid-rock reaction rate of the carbonate rock core and hydrofluoric acid acidization reaction using the method in step (3) k HF-CA =3.6091×10 -9 mol / (cm 2 s);

[0078] (6) Acidification reaction rate of carbonate rock core with hydrofluoric acid k HF-CA Acid-rock reaction rate ratio K CA-SH Estimating the reaction rate between carbonate minerals and hydrofluoric acid in shale k HF-CA-SH =2.6268×10 -8 mol / (cm 2 s);

[0079] (7) The reaction rate of carbonate minerals in shale with hydrofluoric acid k HF-CA-SH Calculate the weight loss Δ of carbonate minerals in shale m HF-CA-SH =0.5572 g;

[0080] (8) Through the rotating rock plate experiment, the acid concentration is controlled to be the same as the acid concentration in step (1), and the weight loss Δ of the shale core and hydrofluoric acid acidizing reaction under fixed experimental conditions is obtained. m HF-SH =0.575 g;

[0081] The acid used can be hydrofluoric acid or earth acid, which can dissolve siliceous minerals. The cores are of standard size, with a bottom diameter of 2.5 cm and a height of 3 cm. The weight loss is measured with an accuracy of 0.001 g. The acid concentration used is 4% by mass. After acidification, the surface is rinsed and dried at 100°C for 24 hours.

[0082] (9) By comparing with Δ m HF-CA-SH Perform difference calculation to obtain the weight loss of siliceous minerals in the shale core due to the acidification reaction with hydrofluoric acid under fixed experimental conditions, Δ m HF-SI-SH =Δ m HF-SH -Δ m HF-CA-SH =0.575-0.5572=0.0177g;

[0083] (10) Calculate the acid-rock reaction rate of the shale core and hydrofluoric acid acidizing reaction using the method in step (3) k HF-SI-SH , is 6,

[0084]

[0085] At this point, the acid-rock reaction rates of carbonate minerals and siliceous minerals in shale are obtained.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A shale multi-mineral chemical kinetic reaction rate differential gravimetric analysis method, characterized in that: The steps are as follows: (1) Through the rotating rock plate experiment, the weight loss of carbonate rock core and hydrochloric acid acidification reaction under fixed experimental conditions was obtained; (2) by rotating the rock plate, controlling the acid concentration to be the same as that of the acid concentration in step (1), and obtaining the weight loss of the shale core in the hydrochloric acid acidification reaction under fixed experimental conditions; (3) calculating the acid-rock reaction rates of hydrochloric acid reacting with the carbonate rock core and the shale core, respectively, and thereby calculating the acid-rock reaction rate ratios of hydrochloric acid reacting with the carbonate rock core and the shale core, respectively; The acid-rock reaction rate is calculated using formula (1): Among them, k acid-rock The acid-rock reaction rate of a specific acid solution and a specific rock, in mol / (cm 2 ·s); Δm R is the weight loss of rock before and after acidification, in g; M R is the molar mass of the rock, in g / mol; Δt is the acid-rock reaction time, in s; S is the acidizing reaction contact area, in cm 2 ;n r is the stoichiometric coefficient of the acid-rock reaction. When the reactant is carbonate rock, n r is 2; The ratio of the acid-rock reaction rate of hydrochloric acid to carbonate rock core k HCl-CA and the acid-rock reaction rate k of shale core and hydrochloric acid HCl-SH Ratio K CA-SH The expression is shown in formula (2): (4) by rotating the rock disk experiment, controlling the acid concentration to be the same as that of the acid concentration in step (1), and obtaining the weight loss of the carbonate rock core in the hydrofluoric acid acidization reaction under fixed experimental conditions; (5) Using the method in step (3), calculate the acid-rock reaction rate k of the carbonate rock core and hydrofluoric acid acidization reaction HF-CA ; (6) The acidification reaction rate k of carbonate rock core and hydrofluoric acid HF-CA and acid-rock reaction rate ratio K CA-SH Estimation of the acid-rock reaction rate k between carbonate minerals in shale and hydrofluoric acid HF-CA-SH , the calculation formula is as follows: The acid-rock reaction rate between carbonate minerals and hydrofluoric acid in shale under the conditions of shale pore fracture structure is obtained by calculation using formula (3); (7) The acid-rock reaction rate k between carbonate minerals in shale and hydrofluoric acid HF-CA-SH Calculate the weight loss Δm of carbonate minerals in shale HF-CA-SH ; (8) Through the rotating rock plate experiment, the acid concentration is controlled to be the same as the acid concentration in step (1), and the weight loss Δm of the shale core and hydrofluoric acid acidizing reaction under fixed experimental conditions is obtained. HF-SH ; (9) By comparing with Δm HF-CA-SH Perform difference calculation to obtain the weight loss Δm of the siliceous minerals in the shale core due to the acidification reaction with hydrofluoric acid under fixed experimental conditions. HF-SI-SH ; (10) Using the method in step (3), calculate the acid-rock reaction rate k of the shale core acidizing reaction with hydrofluoric acid HF-SI-SH , so far, the acid-rock reaction rates of carbonate minerals and siliceous minerals in shale are obtained.

2. The shale multi-mineral chemical kinetic reaction rate differential gravimetric analysis method according to claim 1, characterized in that: In step (1), the rotating rock disc experiment steps are as follows: the cut core is sealed in a rubber sleeve and fixed on the rotating rock disc rotating handle, leaving only the end face of the core to react with the acid solution. The core in the rotating rock disc reactor rotates with the acid solution. After the set time is reached, the core is taken out, dried and weighed to obtain the weight loss of the carbonate rock core in the hydrochloric acid acidification reaction.

3. The shale multi-mineral chemical kinetic reaction rate differential gravimetric analysis method according to claim 2, characterized in that: In the reaction in step (2), the weight loss of the reaction of hydrochloric acid with the shale core = the weight loss of the reaction of hydrochloric acid with the carbonate minerals in the shale.

4. The shale multi-mineral chemical kinetic reaction rate differential gravimetric analysis method according to claim 3, characterized in that: The weight loss of carbonate minerals in shale in step (7) is Δm HF-CA-SH The calculation formula is shown in formula (9): Where k HF-CA-SH M is the acid-rock reaction rate between carbonate minerals in shale and hydrofluoric acid; R is the molar mass of the rock, in g / mol; Δt is the acid-rock reaction time, in s; S is the acidizing reaction contact area, in cm 2 ;n r is the stoichiometric coefficient of the acid-rock reaction. When the reactant is carbonate rock, n r is 2.

5. The shale multi-mineral chemical kinetic reaction rate differential gravimetric analysis method according to claim 1, characterized in that: In step (8), the acid solution used is hydrofluoric acid or mud acid.

6. The shale multi-mineral chemical kinetic reaction rate differential gravimetric analysis method according to claim 4, characterized in that: In step (9), when hydrofluoric acid is used for acidification, carbonate minerals and siliceous minerals in the shale participate in the reaction at the same time. Therefore, the total weight loss after acidification is Δm HF-SH =Δm HF-SI-SH +Δm HF-CA-SH , Δm HF-SI-SH =Δm HF-SH -Δm HF-CA-SH .

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