Chloride ion data correction method based on electrode method

Abstract

The application provides a chloride ion data correction method based on an electrode method. The method comprises the following steps: preparing a plurality of chloride ion standard solutions with different concentrations; heating each standard solution, measuring the temperature and voltage, and fitting a first mathematical expression of each standard solution representing the temperature and voltage relationship; measuring the temperature and voltage of a to-be-measured solution by using a chloride ion detection technology based on the electrode method; bringing the temperature measurement value into the first mathematical expression of each standard solution respectively to obtain the voltage value of each standard solution under the condition of the temperature measurement value, and then fitting a second mathematical expression representing the relationship between the chloride ion concentration and the voltage value under the condition of the temperature measurement value; and bringing the voltage measurement value of the to-be-measured solution into the second mathematical expression to obtain the chloride ion concentration of the to-be-measured solution. The method is simple, eliminates the influence of temperature on the detection value, and can make the detection data more truly reflect the chloride ion content in the solution.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas geological exploration and well logging engineering, in particular to a chloride ion data correction method based on electrode method. BACKGROUND

[0002] The drilling site mainly uses Mohr method to detect the chloride ion content of drilling fluid, which needs hazardous chemicals such as nitric acid, silver nitrate and potassium chromate, and the safety of the detection reagent is hidden, difficult to transport and store, and the operation steps are many, and the detection time is long. Therefore, some enterprises and research institutes have studied the drilling fluid chloride ion measurement technology based on electrode method, for example, CN113671007A discloses a suspension liquid chloride ion online measurement device and measurement method, the measurement device: including a chloride ion composite electrode, the chloride ion composite electrode is directly placed in the drilling fluid suspension liquid to be measured; the chloride ion composite electrode includes a reference electrode end and a chloride ion selective electrode end, so that the suspension liquid chloride ion online measurement device is placed in the drilling fluid to form a stable chloride ion potential; the impurity filtering structure is attached to the contact surface of the chloride ion selective electrode end of the composite electrode and the drilling fluid, which isolates and filters the fine particle impurities in the drilling fluid and simultaneously allows the ions to diffuse through the ion channel; the porous filtering structure is arranged on the contact surface of the reference electrode end and the drilling fluid, which prevents the suspended particles in the drilling fluid from invading and affecting the accuracy of the reference measurement; the diaphragm shell is arranged outside the periphery of the contact surface of the chloride ion selective electrode end and the drilling fluid. However, the technology disclosed in the patent does not consider the influence of temperature on detection.

[0003] The existing drilling fluid chloride ion measurement technology based on electrode method effectively avoids the use of hazardous chemicals, improves the chloride ion detection efficiency, but does not correct the temperature, resulting in unstable detection values at different temperatures, and large differences between the measured data and the true chloride ion content. It is necessary to correct the temperature to make the measured value more truly reflect the chloride ion content of the measured solution. SUMMARY

[0004] The present application aims to solve at least one of the above-mentioned deficiencies in the prior art. For example, one of the purposes of the present application is to more truly reflect the chloride ion content of the measured solution.

[0005] In order to achieve the above-mentioned purpose, the present application provides a chloride ion data correction method based on electrode method.

[0006] The method includes the following steps: preparing multiple standard solutions; wherein the multiple standard solutions are chloride ion standard solutions with different chloride ion concentrations; heating each standard solution and measuring the temperature and voltage of the solution to obtain measurement data for each standard solution; fitting a first mathematical expression reflecting the temperature and voltage relationship for each standard solution based on the measurement data for each standard solution; and using the first mathematical expression for each standard solution to correct the chloride ion detection results of the electrode-based chloride ion detection technology.

[0007] Further, the correction may include: measuring the temperature and voltage of the test solution using an electrode-based chloride ion detection technique; substituting the measured temperature value of the test solution into a first mathematical expression for each standard solution to obtain the voltage value of each standard solution under the temperature measurement condition; fitting a second mathematical expression reflecting the relationship between chloride ion concentration and voltage value under the temperature measurement condition based on the voltage value of each standard solution and the chloride ion concentration of each standard solution; and substituting the measured voltage value of the test solution into the second mathematical expression to obtain the chloride ion concentration of the test solution.

[0008] Furthermore, the standard solution is prepared from water and sodium chloride.

[0009] Furthermore, the method may further include: plotting the measurement data of each standard solution on the same graph to obtain a temperature-voltage calibration chart for standard solutions of different chloride ion concentrations. Even further, the horizontal axis of the temperature-voltage calibration chart may be temperature and the vertical axis may be voltage, or the horizontal axis may be voltage and the vertical axis may be temperature.

[0010] Furthermore, the method may further include: plotting the chloride ion concentration of each standard solution and the voltage value of each standard solution under the temperature measurement condition on the same graph to obtain a chloride ion concentration calibration chart of the test solution under the temperature condition. Further still, the horizontal axis of the chloride ion concentration calibration chart may be voltage, and the vertical axis may be chloride ion concentration; alternatively, the horizontal axis may be voltage, and the vertical axis may be temperature.

[0011] Furthermore, the different chloride ion concentrations refer to ≥3 different chloride ion concentrations.

[0012] Furthermore, the measurement data includes multiple data sets consisting of temperature and voltage, wherein the temperature is between 20 and 60°C. Even further, the number of data sets is ≥3.

[0013] Compared with the prior art, the beneficial effects of the present invention include:

[0014] (1) The method of the present invention is simple and can eliminate or weaken the influence of temperature on the detection value, so that the detection data can more accurately reflect the chloride ion content in the solution.

[0015] (2) The present invention optimizes the chloride ion detection technology based on the electrode method, making the test results of the technology more accurate. Attached Figure Description

[0016] The above and other objects and / or features of the present invention will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0017] Figure 1 Temperature and voltage calibration charts for different standard solutions of the present invention are shown.

[0018] Figure 2 A chloride ion concentration correction diagram of the present invention is shown.

[0019] Figure 3 The error analysis chart between the measured value and the true value of the standard solution is shown. Detailed Implementation

[0020] The electrode-based chloride ion data correction method of the present invention will be described in detail below with reference to exemplary embodiments.

[0021] Exemplary Example 1

[0022] The chloride ion data correction method based on the electrode method may include the following steps:

[0023] S10: Prepare multiple standard solutions; wherein, the multiple standard solutions are chloride ion standard solutions with different chloride ion concentrations.

[0024] In this embodiment, the standard solution is prepared from water and sodium chloride. Alternatively, the water can be pure water.

[0025] In this embodiment, the number of standard solutions can be varied, specifically ≥3 types of chloride ion concentrations, such as 4, 5, 6, 7, 8, 9, 10, 12, 15, etc.

[0026] S20: Heat each standard solution and measure the temperature and voltage of the solution to obtain measurement data for each standard solution.

[0027] In this embodiment, the step further includes plotting a temperature-voltage calibration chart based on the measurement data, that is, plotting the measurement data of each standard solution on the same graph. The horizontal axis of the temperature-voltage calibration chart represents temperature, and the vertical axis represents voltage; alternatively, the axes can be reversed.

[0028] In this embodiment, the measurement data for each standard solution includes multiple data sets, and each data set includes corresponding voltage and temperature data.

[0029] The temperature data in the measurement data are between 20 and 60℃, for example, 23.5℃, 25℃, 30℃, 40℃, 50℃, 55℃, and 56.4℃.

[0030] For each standard solution, the measurement data should include ≥3 data sets, such as 5, 6, 8, 10, 12, 15, etc.

[0031] S30: Based on the measurement data of each standard solution, fit a first mathematical expression for the relationship between temperature and voltage for each standard solution.

[0032] S40: Correct the chloride ion detection results of the electrode-based chloride ion detection technology using the first mathematical expression for each standard solution.

[0033] Specifically, step S40 includes:

[0034] S41: The temperature and voltage of the test solution are measured using an electrode-based chloride ion detection technique. The test solution includes drilling fluid, diluted drilling fluid, completion fluid, etc., but this invention is not limited to these and can also be applied to other test solutions where temperature affects the chloride ion detection results.

[0035] S42: Substitute the measured temperature value of the solution to be tested into the first mathematical expression for each standard solution to obtain the voltage value of each standard solution under the measured temperature condition.

[0036] S43: Based on the voltage value of each standard solution and the chloride ion concentration of each standard solution, fit a second mathematical expression that reflects the relationship between chloride ion concentration and voltage value under the temperature measurement condition.

[0037] S44: Substitute the voltage measurement value of the solution to be tested into the second mathematical expression to obtain the chloride ion concentration of the solution to be tested.

[0038] In this embodiment, step S42 further includes: plotting a chloride ion concentration calibration chart of the test solution under the temperature condition, that is, plotting the chloride ion concentration of each standard solution and the voltage value of each standard solution under the temperature measurement condition on the same graph. The horizontal axis of the chloride ion concentration calibration chart represents voltage, and the vertical axis represents chloride ion concentration, or vice versa.

[0039] Exemplary Example 2

[0040] This invention presents a chloride ion data correction method based on the electrode method, developed through comprehensive research on parameters such as chloride ion standard solution, detection solution, measurement voltage, and temperature. The specific technical solution is as follows:

[0041] (1) Prepare chloride ion standard solutions in different proportions using distilled water and sodium chloride as needed, and calculate the chloride ion concentration C of the chloride ion standard solutions in different proportions. i C i Unit: mg / L.

[0042] (2) Heat standard solutions of chloride ions of different concentrations respectively, and record the changes with temperature T. ij Changing voltage value V ij Among them, T ij The units are ℃ and V. ij The unit is mv, where i represents the i-th concentration of chloride ion standard solution, and j represents the j-th experiment. For example, a C1 concentration chloride ion standard solution at T 11 T 12 T 13 T 14 T 15 T 16 The voltage values ​​are respectively V 11 V 12 V 13 V 14 V 15 V 16 For example, a C2 chloride ion standard solution at T 21 T 22 T 23 T 24 T 25 T 26 The voltage values ​​are respectively V 21 V 22 V 23 V 24 V 25 V 26 As an alternative to the present invention, an electronic balance (heatable) can be used to heat the beaker containing the solution to be tested to different set temperatures, and a chloride ion detection device based on the electrode method can be used to measure the solution voltage at different temperatures.

[0043] (3) Based on the measured voltage values ​​of chloride ion standard solutions of different concentrations at different temperatures, establish temperature-voltage calibration charts for chloride ion standard solutions of different concentrations, such as... Figure 1 As shown in the figure. The horizontal axis of this graph represents the measured temperature, and the vertical axis represents the measured voltage. The values ​​are established based on actual conditions, and different types of data points represent the voltage measurement values ​​of chloride ion standard solutions of different concentrations at different temperatures.

[0044] (4) According toFigure 1 A certain concentration of chloride ion standard solution C i At different temperatures T ij The measured voltage V ij By performing data fitting, the temperature and voltage fitting formula for this concentration of chloride ion standard solution can be obtained, as shown below:

[0045] V i =f(T) i ).

[0046] (5) According to step (4), the temperature and voltage fitting formulas for standard solutions of chloride ions with different concentrations can be obtained. For example, the temperature and voltage fitting formula V1 = f(T1) for standard solution of concentration 1 can be obtained by fitting the data of the measurement voltage at different temperatures, and the temperature and voltage fitting formula V2 = f(T2) for standard solution of concentration 2 can be obtained by fitting the data of the measurement voltage at different temperatures.

[0047] (6) The fitting formula obtained in step (5) can be used to obtain the measurement voltage of a certain concentration of chloride ion standard solution at different temperatures.

[0048] (7) The temperature and voltage of the solution to be tested were measured using an electrode-based chloride ion detection technique.

[0049] (8) Based on the temperature T of the solution to be tested t The temperature T of the solution to be tested is obtained by fitting the temperature and voltage of standard solutions of chloride ions with different concentrations. t Voltage values ​​of standard chloride ion solutions with different concentrations under conditions T. For example, the voltage value V corresponding to the concentration of Cl under condition T. t1 C2 concentration corresponds to voltage value V t2 .

[0050] (9) Establish the temperature T of the solution to be tested according to step (8). t Correction charts for chloride ion concentration under certain conditions, such as Figure 2 As shown in the figure, the vertical axis of the graph represents the chloride ion content of the chloride ion standard solution, and the horizontal axis represents the chloride ion content of the standard solutions with different chloride ion contents at the temperature T of the solution being tested. t The voltage value obtained under the condition of fitting the temperature and voltage formula.

[0051] (10) Obtain the temperature T of the solution to be tested based on the chloride ion concentration calibration chart established in step (9). t The formula for voltage value versus chloride ion content under the given conditions is as follows:

[0052] C t =f(V t ).

[0053] (11) The measuring voltage value V of the solution to be tested tSubstituting the values ​​into the formula established in step (10), the chloride ion content C of the solution to be tested can be obtained. t .

[0054] This invention considers the correlation between chloride ion standard solution, detection solution, measurement voltage and temperature in the chloride ion content detection process based on electrode method. By establishing a calibration chart and method, the influence of temperature on the detection value is eliminated, so that the detection data can more accurately reflect the chloride ion content in the solution.

[0055] The following data comparison further illustrates the effectiveness of the present invention.

[0056] Standard solutions A, B, C, D, E, and F with chloride ion concentrations of 100 mg / L, 200 mg / L, 400 mg / L, 600 mg / L, 800 mg / L, and 1000 mg / L were prepared using distilled water and sodium chloride.

[0057] Without considering the influence of temperature changes, the chloride ion concentration was measured using existing electrode-based chloride ion detection equipment, i.e., direct measurement at room temperature as shown in Table 1. The results are shown in Table 1 below.

[0058] The chloride ion corrected measurement values ​​of each standard solution were obtained using the electrode-based chloride ion data correction method of this invention. The results are shown in Table 1 below. A comparative analysis was performed using the uncorrected direct measurement values ​​and the corrected measurement values. The error was calculated using equation (1), and the error results are shown below. Figure 3 As shown in Table 1, it can be seen that the error after correction by the present invention can be controlled within 5%, which is significantly lower than the error without correction, thus reducing the influence of temperature on the detection value.

[0059]

[0060] Table 1 Error Results

[0061]

[0062] Although the present invention has been described above in conjunction with exemplary embodiments and accompanying drawings, those skilled in the art should understand that various modifications can be made to the above embodiments without departing from the spirit and scope of the claims.

Claims

1. A chloride ion data correction method based on electrode method, characterized in that, The method includes the following steps: Prepare various standard solutions; wherein the various standard solutions are chloride ion standard solutions with different chloride ion concentrations; Each standard solution was heated, and the temperature and voltage of the solution were measured to obtain measurement data for each standard solution. Based on the measurement data of each standard solution, a first mathematical expression reflecting the relationship between temperature and voltage for each standard solution is fitted. The chloride ion detection results of the electrode-based chloride ion detection technology are corrected using the first mathematical expression for each standard solution.

2. The chloride ion data correction method based on the electrode method according to claim 1, characterized in that, The correction includes: The temperature and voltage of the test solution were measured using an electrode-based chloride ion detection technique. The temperature measurement value of the solution to be tested is substituted into the first mathematical expression of each standard solution to obtain the voltage value of each standard solution under the temperature measurement condition. Based on the voltage value and chloride ion concentration of each standard solution, a second mathematical expression reflecting the relationship between chloride ion concentration and voltage value under the temperature measurement condition is fitted. The chloride ion concentration of the solution to be tested is obtained by substituting the voltage measurement value of the solution into the second mathematical expression.

3. The chloride ion data correction method based on the electrode method according to claim 1, characterized in that, The standard solution is prepared from water and sodium chloride.

4. The chloride ion data correction method based on the electrode method according to claim 1, characterized in that, The method further includes plotting the measurement data of each standard solution on the same graph to obtain temperature and voltage calibration graphs for chloride ion standard solutions of different concentrations.

5. The chloride ion data correction method based on the electrode method according to claim 4, characterized in that, The horizontal axis of the temperature-voltage calibration chart is temperature, and the vertical axis is voltage, or the horizontal axis is voltage and the vertical axis is temperature.

6. The chloride ion data correction method based on the electrode method according to claim 1, characterized in that, The method further includes: plotting the chloride ion concentration of each standard solution and the voltage value of each standard solution under the temperature measurement condition on the same graph to obtain a chloride ion concentration calibration chart of the test solution under the temperature condition.

7. The chloride ion data correction method based on the electrode method according to claim 6, characterized in that, The horizontal axis of the chloride ion concentration calibration chart is voltage, and the vertical axis is chloride ion concentration; or, the horizontal axis is voltage, and the vertical axis is temperature.

8. The chloride ion data correction method based on the electrode method according to claim 1, characterized in that, The different chloride ion concentrations refer to ≥3 different chloride ion concentrations.

9. The chloride ion data correction method based on the electrode method according to claim 1, characterized in that, The measurement data includes multiple data sets consisting of temperature and voltage, wherein the temperature is between 20 and 60°C.

10. The chloride ion data correction method based on the electrode method according to claim 9, characterized in that, The number of data groups is ≥3.

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