Method for analyzing corrosion rule of metal material under coal mine

Abstract

The invention discloses an analysis method for a corrosion rule of a metal material under a coal mine. The analysis method comprises the following steps: step 1, checking and recording service environment information of the metal material under the coal mine on site; 2, aiming at the service environment of the metal material, obtaining the corrosion rates of the metal material under different working conditions through a simulation experiment; 3, determining the corrosion rule of each metal material under the coal mine by analyzing the corrosion rate, the corrosion morphology and the product composition corresponding to each factor; and 4, calculating the correlation degree of each corrosion factor through a theoretical method, further evaluating the influence proportion of each factor on corrosion, and defining a main control factor, a secondary factor and the like. The method is simple in step and convenient to implement, the conclusion obtained through the quantitative analysis method is reliable, reliable guidance is provided for corrosion prevention control of the metal material under the coal mine, and popularization is convenient.

Description

Technical Field

[0001] The invention relates to the field of corrosion of metal materials, and more specifically, to an analysis method for the corrosion law of metal materials in coal mines. Background Art

[0002] The description of the background technology in the present invention belongs to the related technology related to the present invention, which is only used to illustrate and facilitate the understanding of the invention content of the present invention, and should not be understood as the applicant explicitly believes or inferred that the applicant believes that it is the prior art of the present invention on the filing date of the first application.

[0003] As the main source of coal energy in my country, the environment under coal mines is complex. Not only is the temperature and humidity changeable, but the composition of media such as air and mine water is even more complex. It has two basic factors, oxygen and water, for electrochemical corrosion of metal materials. Therefore, the corrosion of metal materials in coal mine environments is quite common and serious. According to literature reports, the average corrosion depth of metal materials under coal mines is 0.2mm / a to 1.2mm / a. At present, there are many studies on the corrosion environment under coal mines, but there are few studies on the effects of various factors under coal mines on the corrosion of metal equipment. It is often difficult to accurately and comprehensively determine the effects of various factors on corrosion, and thus it is impossible to propose economical and effective protective measures.

[0004] Therefore, how to comprehensively, specifically and accurately analyze the corrosion laws of metal materials under coal mines, so as to provide data support for anti-corrosion measures for metal materials under coal mines, has become an urgent problem to be solved in this field and a key research topic. Summary of the invention

[0005] In order to effectively determine the corrosion laws of various factors on metal materials under coal mines, the present invention innovatively proposes an analysis method for the corrosion laws of metal materials under coal mines. The method is simple, reasonably designed, easy and accurate to implement, and the data obtained can effectively support subsequent protective measures and is easy to promote and apply.

[0006] A method for analyzing the corrosion law of metal materials in coal mines comprises the following steps:

[0007] Step 1: Check and record the humidity range, temperature range, medium mineralization range, ion content, coal dust concentration range, air composition and content in the coal mine on site;

[0008] Step 2: For the service environment of metal materials, the corrosion rate of the materials under different humidity, temperature, mineralization, coal powder content and other factors is obtained through simulation experiments;

[0009] Step 3, by analyzing the corrosion rate corresponding to each factor, clarify the corrosion law of humidity, temperature, mineralization and solid content on various metal materials in coal mines;

[0010] Step 4: Calculate the correlation degree of each corrosion factor using the grayscale correlation analysis method.

[0011] Furthermore, step 3 specifically includes:

[0012] Based on the results of the simulation experiments, the corrosion rate is analyzed as the levels of each factor change;

[0013] Based on the morphology analysis of the metal substrate after the experiment, the corrosion type is determined, such as uniform corrosion or local corrosion;

[0014] Combined with the detection and analysis of the macro and micro morphology and composition of the corrosion products, the corrosion mechanism is further clarified.

[0015] Furthermore, step 4 specifically includes:

[0016] Determine the evaluation index system, collect evaluation data, and clarify the comparison series and reference series;

[0017] Standardize or normalize the indicator series data;

[0018] Determine the maximum and minimum absolute differences between the elements of the comparison sequence of the evaluated object and the reference sequence (corrosion rate), and calculate the correlation coefficient between each comparison sequence and the corresponding element of the reference sequence;

[0019] The correlation degree is calculated and sorted according to its size, so as to clarify the influence proportion of humidity, temperature, medium mineralization and coal powder content on corrosion.

[0020] Furthermore, the evaluation object sequence is the corrosion factor level, and the reference sequence is the corrosion rate;

[0021] In the above-mentioned method for analyzing the corrosion laws of metal materials in coal mines, the viewing and recording information described in step 1 also includes the material of the metal material and the service environment, and the service environment includes the water sprinkling area, the soaking area, the humid area, the pH of the groundwater and the installation method of the equipment material.

[0022] In the above-mentioned method for analyzing the corrosion law of metal materials in coal mines, the simulation experiment described in step 2 is a salt spray test according to the GB / T 10125-2021 standard, a corrosion full immersion test according to the JB / T7901-1999 standard, and a constant temperature and humidity test according to the GB / T 2423.3-2016 standard. The salt spray test equipment is a salt spray test chamber, the constant temperature and humidity test equipment is a programmable constant temperature and humidity instrument, and the corrosion full immersion test equipment is a high temperature and high pressure reactor.

[0023] In the above-mentioned method for analyzing the corrosion law of metal materials in coal mines, the simulation experiment described in step 2 is grouped through orthogonal experiments.

[0024] In the above-mentioned method for analyzing the corrosion law of metal materials in coal mines, the corrosion rates described in step 2 and step 3 are both uniform corrosion rates, and the calculation formula for the uniform corrosion rate is:

[0025] R= 8.76×10 7 ×(M-M1)

[0026] S×T×D

[0027] Where R is the uniform corrosion rate, mm / a; M is the mass of the sample before the experiment, g; M1 is the mass of the sample after the experiment, g; S is the total area of ​​the sample, cm 2 ; T is the test time, h; D is the density of the material, kg / m 3 .

[0028] In the above-mentioned method for analyzing the corrosion law of metal materials in coal mines, the microscopic morphology described in step 3 is detected by means of SEM, and the composition of the corrosion products is detected by means of XRD and EDS.

[0029] In the above-mentioned method for analyzing the corrosion law of metal materials in coal mines, the maximum value of the correlation degree described in step 4 is 1. The larger the correlation degree, the greater the relationship between the comparison series and the reference series.

[0030] With the above solution, the present invention can at least achieve the following beneficial effects:

[0031] The method of the present invention is simple, reasonably designed and easy to implement; the orthogonal method is used to reduce the experimental workload and reduce costs; the grayscale correlation analysis method is used to quantitatively analyze the influence of various factors on corrosion in the later stage; the obtained experimental data is reliable, and reliable guidance is provided for the anti-corrosion control of metal materials in coal mines, which is convenient for subsequent promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The present invention is a flowchart for implementing the method. DETAILED DESCRIPTION

[0033] The present application is further described below in conjunction with embodiments.

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, in the following description, different "one embodiment" or "embodiment" does not necessarily refer to the same embodiment. Different embodiments can be replaced or combined, and for ordinary technicians in this field, other implementation methods can be obtained based on these embodiments without creative work.

[0035] Example 1

[0036] like Figure 1As shown, the method for analyzing the corrosion law of metal materials in coal mines of the present invention comprises the following steps:

[0037] Step 1: Check and record the humidity range, temperature range, medium mineralization range, ion content, coal dust concentration range, air composition and content in the coal mine on site;

[0038] Step 2: For the service environment of metal materials, the corrosion rate of the materials under different humidity, temperature, mineralization, coal powder content and other factors is obtained through simulation experiments;

[0039] Step 3, by analyzing the corrosion rate corresponding to each factor, clarify the corrosion law of each metal material in the coal mine due to humidity, temperature, mineralization, solid content, etc.; first, based on the results of the simulation experiment, analyze the changes in corrosion rate with the changes in the levels of each factor; secondly, based on the morphology analysis of the metal matrix after the experiment, clarify the corrosion type, such as uniform corrosion or local corrosion; finally, combined with the detection and analysis of the macro and micro morphology and composition of the corrosion products, further clarify the corrosion mechanism.

[0040] Step 4, calculate the correlation of each corrosion factor with the help of gray correlation analysis. First, determine the evaluation index system, collect evaluation data, and clarify the comparison series and reference series; second, standardize or normalize the index series data; third, determine the maximum and minimum absolute differences between the elements corresponding to the comparison series (corrosion factor level) of the evaluated object and the reference series (corrosion rate), and calculate the correlation coefficient between each comparison series and the corresponding elements of the reference series; finally, calculate the correlation, sort the correlation according to the size of the correlation, and then clarify the influence of humidity, temperature, medium mineralization and coal powder content on corrosion.

[0041] In order to further verify the effect of the present invention, the content of the present invention is experimentally verified, and the influence of various factors on the corrosion of metal equipment is analyzed in the service environment of a coal mine. The specific steps are as follows:

[0042] (1) In a coal mine, the relative humidity is between 50% and 95%, the temperature is between 18°C ​​and 40°C, and the mineralization is between 4.2×10 3 mg / L~1.5×10 5 mg / L, material is Q235 carbon steel;

[0043] (2) In the simulation experiment, the selected temperatures were 20°C, 30°C, and 40°C, the relative humidity was 60%, 80%, and 95%, and the medium mineralization was 5.0×10 3 , 2.0×10 4 , 1.5×10 5 , an orthogonal experimental table is listed according to three factors (temperature, relative humidity, medium mineralization) and three levels, as shown in the following table:

[0044] Table 1 Orthogonal experiment table

[0045] Experiment number Temperature ℃ Relative humidity % Mineralization mg / L 1 20 60 <![CDATA[5.0×10 3 ]]> 2 20 80 <![CDATA[2.0×10 4 ]]> 3 20 95 <![CDATA[1.5×10 5 ]]> 4 30 60 <![CDATA[2.0×10 4 ]]> 5 30 80 <![CDATA[1.5×10 5 ]]> 6 30 95 <![CDATA[5.0×10 3 ]]> 7 40 60 <![CDATA[1.5×10 5 ]]> 8 40 80 <![CDATA[5.0×10 3 ]]> 9 40 95 <![CDATA[2.0×10 4 ]]>

[0046] (3) Nine groups of simulation experiments were conducted using the basic orthogonal experimental method. The simulation experiment period was 7 days. The uniform corrosion rate corresponding to the three levels of temperature, relative humidity and mineralization was measured by the weight loss method and was in the range of 0.089 mm / a to 1.654 mm / a.

[0047] (4) Using relative humidity, temperature and mineralization as comparison sequences and uniform corrosion rate as reference sequence to construct original evaluation data, and perform grayscale correlation analysis;

[0048] Table 2 Evaluation system

[0049]

[0050]

[0051] (5) The original data is standardized or normalized, and then the correlation coefficient and correlation degree are calculated in turn. The correlation coefficients of relative humidity, temperature and mineralization on uniform corrosion rate are calculated to be 0.721, 0.741 and 0.520 respectively;

[0052] Table 3 Standardization

[0053] temperature Relative humidity Mineralization Uniform corrosion rate 0.667 0.766 0.086 0.093 0.667 1.021 0.343 0.250 0.667 1.213 2.571 1.021 1.000 0.766 0.343 0.800 1.000 1.021 2.571 1.153 1.000 1.213 0.086 1.302 1.333 0.766 2.571 1.133 1.333 1.021 0.086 1.520 1.333 1.213 0.343 1.732

[0054] Table 4 Grayscale correlation coefficient calculation

[0055]

[0056]

[0057] (6) Based on the above information, the corrosion degree of metal materials in coal mines increases with the increase of humidity, temperature and mineralization of solution medium. Among them, temperature has the greatest impact on material corrosion, followed by humidity. During the later maintenance, strengthening ventilation can reduce the relative humidity and temperature of the environment, which can effectively prevent the corrosion of metal materials. The data involved in this case are detailed in the table below.

[0058]

[0059] Example 2

[0060] The scheme of the embodiment of the present invention is further described in detail through field tests in coal mines. The details are as follows:

[0061] (1) Hang Q235 carbon steel hanging plates in different watering areas and non-watering areas of the main inclined shaft, with relative humidity between 80% and 95%, temperature between 26.5℃ and 32.7℃, and mineralization between 4.6×10 3 mg / L~1.2×10 5 mg / L;

[0062] (2) Hang Q235 carbon steel hanging plates in different areas of the transport chute and the return air chute, with relative humidity between 50% and 85%, temperature between 21.5℃ and 30.5℃, and mineralization between 1.9×10 4 mg / L~9.2×10 4 mg / L;

[0063] (3) Hang Q235 carbon steel hanging plates in different areas of the fully mechanized mining face, with relative humidity between 70% and 93%, temperature between 27.5°C and 37.5°C, and mineralization between 1.7×10 3 mg / L~1.5×10 5 mg / L.

[0064] (4) Nine sets of field experiments were conducted based on the orthogonal experimental method. The experimental period was 14 days. Finally, the uniform corrosion rate corresponding to the three levels of temperature, relative humidity and mineralization was measured by the weight loss method in the range of 0.105mm / a to 1.470mm / a. The specific field tests are shown in the following table:

[0065] Table 4 Orthogonal experiment table

[0066] Experiment number Temperature ℃ Relative humidity % Mineralization mg / L 1 23.5 65.5 <![CDATA[4.9×10 3 ]]> 2 23.5 82.4 <![CDATA[2.2×10 4 ]]> 3 23.5 93.8 <![CDATA[1.1×10 5 ]]> 4 31.2 65.5 <![CDATA[2.2×10 4 ]]> 5 31.2 82.4 <![CDATA[1.1×10 5 ]]> 6 31.2 93.8 <![CDATA[4.9×10 3 ]]> 7 37.2 65.5 <![CDATA[1.1×10 5 ]]> 8 37.2 82.4 <![CDATA[4.9×10 3 ]]> 9 37.2 93.8 <![CDATA[2.2×10 4 ]]>

[0067] (6) Using relative humidity, temperature and mineralization as comparison sequences and uniform corrosion rate as reference sequence to construct original evaluation data, and perform grayscale correlation analysis;

[0068] Table 5 Evaluation system

[0069] temperature Relative humidity Mineralization Uniform corrosion rate 23.5 65.5 4900 0.105 23.5 82.4 22000 0.211 23.5 93.8 110000 0.917 31.2 65.5 22000 0.877 31.2 82.4 110000 1.175 31.2 93.8 4900 1.197 37.2 65.5 110000 1.114 37.2 82.4 4900 1.308 37.2 93.8 22000 1.470

[0070] (7) The original data is standardized or normalized, and then the correlation coefficient and correlation degree are calculated in turn. The correlation coefficients of relative humidity, temperature and mineralization on uniform corrosion rate are calculated to be 0.580, 0.598 and 0.419 respectively;

[0071] Table 6 Grayscale correlation coefficient calculation

[0072] temperature Relative humidity Mineralization 0.508 0.525 1.000 0.476 0.573 0.742 0.809 0.768 0.336 0.849 0.915 0.610 0.750 0.747 0.387 0.856 0.729 0.378 0.652 0.991 0.373 0.652 0.790 0.356 0.633 0.662 0.395

[0073] Combined with the field test in the coal mine, it can be known that the corrosion degree of metal materials in the coal mine increases with the increase of humidity, temperature and solution medium mineralization, among which temperature has the greatest influence on the corrosion of materials, followed by humidity. The data involved in the implementation case is based on laboratory simulation test data and field data in the coal mine. The data is true and reliable, and the obtained simulation results are consistent with the corrosion characteristics of a certain coal mine. The above is only a preferred implementation case of the present invention, and is not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made to the essential content of the present invention should be included in the protection scope of the present invention.

[0074] It should be noted that the above embodiments can be freely combined as needed. The above description is only the preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for analyzing the corrosion law of metal materials in coal mines, characterized in that: The following steps are involved: Step 1: Check and record the humidity range, temperature range, medium mineralization range, ion content, coal dust concentration range, air composition and content in the coal mine on site; Step 2: For the service environment of metal materials, the corrosion rate of the materials under different humidity, temperature, mineralization, coal powder content and other factors is obtained through simulation experiments; Step 3, by analyzing the corrosion rate corresponding to each factor, clarify the corrosion law of humidity, temperature, mineralization and solid content on various metal materials in coal mines; Step 4: Calculate the correlation degree of each corrosion factor using the grayscale correlation analysis method.

2. The method for analyzing the corrosion law of metal materials in coal mines according to claim 1, characterized in that: Step 3 specifically includes: Based on the results of the simulation experiments, the corrosion rate is analyzed as the levels of each factor change; Based on the morphology analysis of the metal substrate after the experiment, the corrosion type is determined, such as uniform corrosion or local corrosion; Combined with the detection and analysis of the macro and micro morphology and composition of the corrosion products, the corrosion mechanism is further clarified.

3. The method for analyzing the corrosion law of metal materials in coal mines according to claim 2, characterized in that: Step 4 specifically includes: Determine the evaluation index system, collect evaluation data, and clarify the comparison series and reference series; Standardize or normalize the indicator series data; Determine the maximum and minimum absolute differences between the elements of the comparison sequence of the evaluated object and the reference sequence (corrosion rate), and calculate the correlation coefficient between each comparison sequence and the corresponding element of the reference sequence; The correlation degree is calculated and sorted according to its size, so as to clarify the influence proportion of humidity, temperature, medium mineralization and coal powder content on corrosion.

4. The method for analyzing the corrosion law of metal materials in coal mines according to claim 3, characterized in that: The evaluation object sequence is the corrosion factor level, and the reference number sequence is the corrosion rate.

5. The method for analyzing the corrosion law of metal materials in coal mines according to claim 1, characterized in that: Step 1 also includes checking and recording the material and service environment of the metal material, wherein the service environment includes a water sprinkling area, a soaking area, a humid area, the pH of groundwater, and the installation method of the equipment material.

6. The method for analyzing the corrosion law of metal materials in coal mines according to claim 1, characterized in that: The simulation experiment described in step 2 is a salt spray test according to the GB / T 10125-2021 standard, a corrosion full immersion test according to the JB / T7901-1999 standard, and a constant temperature and humidity test according to the GB / T 2423.3-2016 standard. The salt spray test equipment is a salt spray test chamber, the constant temperature and humidity test equipment is a programmable constant temperature and humidity instrument, and the corrosion full immersion test equipment is a high temperature and high pressure reactor.

7. The method for analyzing the corrosion law of metal materials in coal mines according to claim 1, characterized in that: The simulation experiments described in step 2 are grouped by orthogonal experiments.

8. The method for analyzing the corrosion law of metal materials in coal mines according to claim 1, characterized in that: The corrosion rates described in step 2 and step 3 are both uniform corrosion rates, and the uniform corrosion rate calculation formula is: Where R is the uniform corrosion rate, mm / a; M is the mass of the sample before the experiment, g; M1 is the mass of the sample after the experiment, g; S is the total area of ​​the sample, cm 2 ; T is the experimental time, h; D is the density of the material, kg / m 3 .

9. The method for analyzing the corrosion law of metal materials in coal mines according to claim 1, characterized in that: The microstructure described in step 3 is detected by means of SEM, and the composition of the corrosion products is detected by means of XRD and EDS.

10. The method for analyzing the corrosion law of metal materials in coal mines according to claim 1, characterized in that: The maximum value of the association degree described in step 4 is 1.

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