Method, device and equipment for measuring porosity of rock debris based on nuclear magnetic resonance

Abstract

The invention relates to the technical field of rock debris detection, and discloses a method, device and equipment for measuring the porosity of rock debris based on nuclear magnetic resonance, and the method comprises the following steps: preparing a to-be-measured sample by using to-be-measured rock debris and a resin curing agent, and calculating the apparent volume of the to-be-measured rock debris based on the to-be-measured sample and the resin curing agent; obtaining the mass of the resin curing agent in the to-be-detected sample and a first scale coefficient of the mass of the resin curing agent and the nuclear magnetic resonance semaphore, and calculating a first signal component of the resin curing agent in the to-be-detected sample; obtaining the total amount of nuclear magnetic resonance signals of the to-be-detected sample, and determining a second signal component of the to-be-detected rock debris; and obtaining a second scale coefficient of the water volume and the nuclear magnetic resonance semaphore, and calculating the porosity of the rock debris to be measured based on the second signal component. The total volume of the rock debris is indirectly measured by using the nuclear magnetic property difference between the resin curing agent and the rock debris, so that the manual operation error is reduced; the sample can be stored for a long time and repeatedly measured, the repeated operation process is simplified, and the measurement precision and the measurement efficiency are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of debris detection, and particularly relates to a method and device for measuring the porosity of debris based on nuclear magnetic resonance and equipment. BACKGROUND

[0002] Both drilling cores and debris are rock samples that can reflect information related to the formation. The porosity, permeability and oil saturation of the debris / cores are core indicators for evaluating oil and gas reserves and productivity, and the porosity is the primary indicator for reflecting the reservoir space. The core is the most intuitive data for reflecting the actual situation of the formation, but it is difficult to obtain and has a high cost. In comparison, the debris is naturally discharged to the ground with the drilling fluid, and thus has a low cost and a large quantity. Therefore, accurate measurement of the porosity of the debris is of great significance to the drilling site of the oil field and the later exploration and development.

[0003] The low-field nuclear magnetic measurement of the porosity has the advantages of non-destructiveness, rapidity, portability and comprehensive information, and thus becomes an ideal method for measuring the porosity of the debris, and is particularly suitable for scenes that require real-time analysis on site, high environmental protection requirements or sample scarcity, and provides more efficient and accurate technical support for oil and gas exploration and development and geological research. The existing methods for measuring the porosity of the debris by nuclear magnetic resonance spectroscopy (NMR) include: nuclear magnetic resonance hydrogen spectroscopy (NMR-H), nuclear magnetic resonance hydrogen-fluorine spectroscopy (NMR-H,F), and an improved method of NMR-H, which have the disadvantages of being greatly affected by human operation, complex operation process, and the need for multiple NMR signal acquisition. SUMMARY

[0004] Therefore, the present application provides a method, device and equipment for measuring the porosity of the debris based on nuclear magnetic resonance, so as to solve the problems of being greatly affected by human operation, complex operation process and the need for multiple NMR signal acquisition.

[0005] In a first aspect, the present application provides a method for measuring the porosity of the debris based on nuclear magnetic resonance, which comprises: The measured sample is prepared by using the measured debris and a resin curing agent, and the apparent volume of the measured debris is calculated based on the measured sample and the resin curing agent; The mass of the resin curing agent in the measured sample, the first calibration coefficient of the mass of the resin curing agent and the amount of the nuclear magnetic resonance signal are obtained, and the first signal component of the resin curing agent in the measured sample is calculated based on the mass of the resin curing agent and the first calibration coefficient; Obtaining the total amount of nuclear magnetic resonance signals of the sample to be measured, and combining the first signal component of the resin curing agent in the sample to be measured to determine the second signal component of the rock debris to be measured in the sample to be measured; Obtaining the second calibration coefficient of the water volume and the amount of nuclear magnetic resonance signals, and calculating the porosity of the rock debris to be measured based on the second signal component.

[0006] The method for measuring the porosity of rock debris based on nuclear magnetic resonance provided by the application fixes the state of the rock debris to be measured by using the resin curing agent, avoids the problem of volatilization of pore fluid during batch sample testing, indirectly measures the total volume of rock debris by using the difference in nuclear magnetic properties between the resin curing agent and the rock debris, reduces human operation errors, can store the sample for a long time, repeatedly measures, simplifies the repeated operation process, and improves the measurement accuracy and efficiency.

[0007] In an optional embodiment, the sample to be measured is prepared by using the rock debris to be measured and the resin curing agent, comprising: The optimal mass ratio of the resin and the curing agent is determined through experimental tests, and the resin and the curing agent are mixed and stirred based on the optimal mass ratio to obtain the resin curing agent. The rock debris to be measured is placed into a mold, and the resin curing agent is poured into the mold for stirring until the rock debris to be measured is completely covered by the resin curing agent. After the resin curing agent is solidified, the sample to be measured is formed.

[0008] In an optional embodiment, after the resin curing agent is solidified, the edges with bubbles and the excess parts are polished off by using sandpaper to obtain the sample to be measured with a standard shape.

[0009] The method for measuring the porosity of rock debris based on nuclear magnetic resonance provided by the application determines the optimal mass ratio of the resin and the curing agent through experiments, reduces the amount of bubbles and the maximum hardness after solidification, reduces the measurement error, optimizes the sample to be measured after solidification by polishing, removes the excess parts, and ensures the accuracy of the volume measurement of the sample to be measured.

[0010] In an optional embodiment, the apparent volume of the rock debris to be measured is calculated based on the sample to be measured and the resin curing agent, comprising: Obtaining the mass of the sample to be measured, the mass of the rock debris to be measured, determining the mass of the resin curing agent, and calculating the volume of the resin curing agent based on the density of the resin curing agent. Obtaining the volume of the sample to be measured, and determining the apparent volume of the rock debris to be measured based on the volume of the resin curing agent.

[0011] The method for measuring the porosity of the rock debris based on the nuclear magnetic resonance provided by the application calculates the volume of the resin curing agent by the known mass and density of the resin curing agent, reduces the error of the volume measurement by using the certainty of the physical formula, determines the apparent volume of the rock debris based on the volume of the sample to be measured and the volume of the resin curing agent, improves the accuracy of the calculation of the apparent volume of the rock debris, and further provides more accurate data support for the subsequent analysis of the related characteristics of the rock debris.

[0012] In an optional embodiment, the mass of the resin curing agent in the sample to be measured, the first calibration coefficient of the mass of the resin curing agent and the amount of the nuclear magnetic resonance signal are obtained, and the first signal component of the resin curing agent in the sample to be measured is calculated based on the mass of the resin curing agent and the first calibration coefficient, including: The mass of the resin curing agent standard sample and the corresponding amount of the nuclear magnetic resonance signal are obtained, and the first calibration coefficient is determined based on the mass of the resin curing agent standard sample and the corresponding amount of the nuclear magnetic resonance signal; The mass of the resin curing agent in the sample to be measured is multiplied by the first calibration coefficient to obtain the first signal component of the resin curing agent in the sample to be measured.

[0013] In an optional embodiment, the total amount of the nuclear magnetic resonance signal of the sample to be measured is obtained, and the second signal component of the rock debris to be measured in the sample to be measured is determined in combination with the first signal component of the resin curing agent in the sample to be measured, including: The total amount of the nuclear magnetic resonance signal of the sample to be measured is subtracted from the first signal component of the resin curing agent in the sample to be measured to obtain the second signal component of the rock debris to be measured in the sample to be measured.

[0014] The method for measuring the porosity of the rock debris based on the nuclear magnetic resonance provided by the application determines the first calibration coefficient by obtaining the mass of the resin curing agent standard sample and the corresponding amount of the nuclear magnetic resonance signal, accurately establishes the corresponding relationship between the mass of the resin curing agent and the signal amount, and further accurately calculates the first signal component of the resin curing agent in the sample to be measured. The second signal component of the rock debris to be measured can be effectively separated by subtracting the first signal component from the total amount of the nuclear magnetic resonance signal of the sample to be measured, the measurement error of the rock debris signal caused by the signal interference of the resin curing agent is reduced, and the reliability of the subsequent analysis is ensured.

[0015] In an optional embodiment, the second calibration coefficient of the water volume and the amount of the nuclear magnetic resonance signal is obtained, and the porosity of the rock debris to be measured is calculated based on the second signal component, including: The volume of the water standard sample and the corresponding amount of the nuclear magnetic resonance signal are obtained, and the second calibration coefficient is obtained based on the volume of the water standard sample and the corresponding amount of the nuclear magnetic resonance signal; The second signal component is divided by the second calibration coefficient to obtain the pore volume of the rock debris to be measured; The porosity of the rock debris to be measured is obtained based on the pore volume and the apparent volume of the rock debris to be measured.

[0016] The method for measuring the porosity of rock debris based on nuclear magnetic resonance provided by the application determines the second calibration coefficient by obtaining the volume of the water standard sample and the corresponding nuclear magnetic resonance signal amount, accurately establishes the correspondence between the water volume and the nuclear magnetic resonance signal amount, and combines the second signal component to calculate the pore volume by using the second calibration coefficient, so that the error caused by the inaccurate correspondence between the signal and the volume is reduced, the pore volume calculation is more accurate, and the accuracy of the porosity calculation is improved.

[0017] In a second aspect, the application provides a device for measuring the porosity of rock debris based on nuclear magnetic resonance, which comprises: A to-be-measured sample preparation module is configured to prepare a to-be-measured sample by using to-be-measured rock debris and a resin curing agent, and to calculate the apparent volume of the to-be-measured rock debris based on the to-be-measured sample and the resin curing agent. A first signal component calculation module is configured to obtain the mass of the resin curing agent in the to-be-measured sample, a first calibration coefficient of the mass of the resin curing agent and the nuclear magnetic resonance signal amount, and to calculate the first signal component of the resin curing agent in the to-be-measured sample based on the mass of the resin curing agent and the first calibration coefficient. A second signal component calculation module is configured to obtain the total amount of the nuclear magnetic resonance signal of the to-be-measured sample, and to determine the second signal component of the to-be-measured rock debris in the to-be-measured sample in combination with the first signal component of the resin curing agent in the to-be-measured sample. A porosity calculation module is configured to obtain a second calibration coefficient of the water volume and the nuclear magnetic resonance signal amount, and to calculate the porosity of the to-be-measured rock debris based on the second signal component.

[0018] In a third aspect, the application provides a computer device, which comprises a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the method of the first aspect or any of the corresponding embodiments thereof.

[0019] In a fourth aspect, the application provides a computer readable storage medium, which stores computer instructions, and the computer instructions are used to make the computer execute the method of the first aspect or any of the corresponding embodiments thereof. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the specific embodiments of the application or the technical solutions in the prior art, the drawings needed in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the application, and those skilled in the art can also obtain other drawings according to these drawings without creating any inventive labor.

[0021] Figure 1 It is a flowchart of the method for measuring the porosity of rock debris based on nuclear magnetic resonance according to the embodiment of the application. Figure 2 is a flow chart of another method for measuring rock debris porosity based on nuclear magnetic resonance according to an embodiment of the present application; Figure 3 is a physical diagram of a sample to be measured in one specific embodiment of the method for measuring rock debris porosity based on nuclear magnetic resonance according to an embodiment of the present application; Figure 4 is a structural block diagram of the device for measuring rock debris porosity based on nuclear magnetic resonance according to an embodiment of the present application; Figure 5 is a hardware structure schematic diagram of the computer device of an embodiment of the present application. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in connection with the drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0023] The existing methods for measuring rock debris porosity by using NMR instruments include: NMR-H probe rock debris porosity measurement method, NMR-H, F probe rock debris porosity measurement method, and improved NMR-H probe rock debris porosity measurement method. In the NMR-H probe rock debris porosity measurement method, water needs to be added to a specified liquid level, which has human error, and the operation requirement is high; the wiping effect of the fluid on the surface of the sample to be measured affects the measurement result. In the NMR-H, F probe rock debris porosity measurement method, two probes H and F are needed, and the instrument is relatively complex; the centrifugation step affects the operation efficiency, and whether the centrifugal force is appropriate affects the measurement result; the fluorinated liquid FC-40 has a high cost and is low in toxicity, and needs to be recycled and processed, which has a high operation cost. In the improved NMR-H probe rock debris porosity measurement method, the wiping effect of the fluid on the surface of the sample to be measured affects the measurement result.

[0024] Based on the above problems, the embodiments of the present application provide a method for measuring rock debris porosity based on nuclear magnetic resonance. The state of the rock debris to be measured is fixed by using a resin curing agent, and the total volume of the rock debris is indirectly measured by using the difference in nuclear magnetic properties between the resin curing agent and the rock debris, so as to achieve the effects of reducing human measurement error, simplifying repeated operation, and improving measurement accuracy.

[0025] According to the embodiment of the present application, a method for measuring the porosity of rock debris based on nuclear magnetic resonance is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in a different order.

[0026] In this embodiment, a method for measuring the porosity of rock debris based on nuclear magnetic resonance is provided, which can be used in the computer system described above, Figure 1 is a flowchart of a method for measuring the porosity of rock debris based on nuclear magnetic resonance according to the embodiment of the present application, as shown in Figure 1 , the flowchart includes the following steps: Step S101, preparing a sample to be measured by mixing the rock debris to be measured with a resin curing agent, and calculating the apparent volume of the rock debris to be measured based on the sample to be measured and the resin curing agent.

[0027] Specifically, in this embodiment, the amount of nuclear magnetic resonance signal is obtained by using the H probe of the NMR instrument. The NMR instrument is selected as a conventional NMR core analyzer, which is composed of a spectrometer unit, a magnet unit, a radio frequency unit, an acquisition computer and software. In order to facilitate the transportation back and forth between the drilling site, a portable logging nuclear magnetic analysis instrument with integrated structure design and a main magnetic field strength of 0.14T (corresponding to the H nuclear resonance frequency of 6MHz) is recommended.

[0028] The core is to mix a proper amount of rock debris to be measured with a resin curing agent. By calibrating the mass-volume linear relationship of the resin curing agent and the mass-nuclear magnetic signal amount linear relationship, the NMR signal amount of the sample to be measured prepared by mixing the rock debris to be measured with the resin curing agent is measured, and then the NMR signal component of the resin curing agent in the sample to be measured and the corresponding volume are subtracted, so as to obtain the pore volume and total volume of the rock debris to be measured, and further calculate the porosity of the rock debris to be measured.

[0029] The whole process is divided into a sample preparation stage and a sample measurement stage. In the sample preparation stage, the rock debris to be measured and the resin curing agent are stirred and mixed, and after the resin curing agent is solidified, the sample to be measured is obtained. The volume of the sample to be measured and the volume of the resin curing agent used are measured, and the apparent volume of the rock debris to be measured is obtained by subtracting the two.

[0030] Step S102, obtaining the mass of the resin curing agent in the sample to be measured, the first calibration coefficient of the mass of the resin curing agent and the nuclear magnetic resonance signal amount, and calculating the first signal component of the resin curing agent in the sample to be measured based on the mass of the resin curing agent and the first calibration coefficient.

[0031] Specifically, in preparation of the sample to be measured, the mass of the resin curing agent used is synchronously counted, in the sample measurement stage, a first calibration coefficient of the mass of the resin curing agent and the amount of the nuclear magnetic resonance signal is obtained by experimental method, the mass of the resin curing agent in the sample to be measured is multiplied by the first calibration coefficient, and a first signal component contributed by the resin curing agent in the sample to be measured is calculated.

[0032] In step S103, the total amount of the nuclear magnetic resonance signal of the sample to be measured is obtained, and a second signal component of the rock debris to be measured in the sample to be measured is determined in combination with the first signal component of the resin curing agent in the sample to be measured.

[0033] Specifically, the total amount of the nuclear magnetic resonance signal of the sample to be measured is obtained by using the NMR instrument, and the second signal component of the rock debris to be measured is obtained by subtracting the first signal component of the resin curing agent from the total amount of the nuclear magnetic resonance signal of the sample to be measured.

[0034] In step S104, a second calibration coefficient of the water volume and the amount of the nuclear magnetic resonance signal is obtained, and the porosity of the rock debris to be measured is calculated based on the second signal component.

[0035] Specifically, the second calibration coefficient of the water volume and the amount of the nuclear magnetic resonance signal is obtained by experimental method, and the pore volume of the rock debris to be measured is determined according to the second calibration coefficient and the second signal component, and the porosity of the rock debris is calculated according to the pore volume of the rock debris and the apparent volume of the rock debris to be measured.

[0036] The method for measuring the porosity of rock debris based on nuclear magnetic resonance provided in the embodiment fixes the state of the rock debris to be measured by using the resin curing agent, avoids the problem of volatilization of pore fluid in batch sample testing, indirectly measures the total volume of the rock debris by using the difference in nuclear magnetic properties between the resin curing agent and the rock debris, reduces the human operation error, can store the sample for a long time, repeatedly measures, simplifies the repeated operation process, and improves the measurement accuracy and the measurement efficiency.

[0037] In the embodiment, a method for measuring the porosity of rock debris based on nuclear magnetic resonance is provided, which can be used in the computer system, Figure 2 is a flowchart of the method for measuring the porosity of rock debris based on nuclear magnetic resonance according to the embodiment of the present application, as Figure 2 shown, the flowchart includes the following steps: In step S201, a sample to be measured is prepared by using the rock debris to be measured and the resin curing agent, and the apparent volume of the rock debris to be measured is calculated based on the sample to be measured and the resin curing agent.

[0038] Specifically, the preparation of the sample to be measured by using the rock debris to be measured and the resin curing agent in the above step S201 includes: In step S2011, the optimal mass ratio of the resin and the curing agent is determined by experimental test, and the resin and the curing agent are mixed and stirred based on the optimal mass ratio to obtain the resin curing agent.

[0039] Specifically, the resin curing agent is formed by fully mixing epoxy resin and curing agent in a certain proportion. The same set of epoxy resin and curing agent are combined in different mass ratios, and the curing time, heat dissipation, hardness and other effects are different. The longer the curing time of the resin curing agent, the slower the heat dissipation, the greater the hardness, the smaller the nuclear magnetic T2 value of the resin curing agent, and the greater the test error. Therefore, the optimal mass ratio should be selected for the experiment. Some resin curing agents will completely solidify within ten minutes after mixing and stirring. Such resin curing agents will generate a large amount of heat during the rapid solidification process, causing water evaporation in the cuttings and generating bubbles, which affects the accuracy of volume measurement. Through multiple experimental tests, it is found that when the ratio of resin to curing agent is 2:1, the fastest curing and maximum hardness effect can be achieved, but it is not suitable for the present embodiment. When the ratio of resin to curing agent is 5:3, the curing time is lengthened, the maximum hardness is reduced, and the amount of bubbles is reduced. Experimental results show that the optimal mass ratio of resin to curing agent is 5:3. The resin and the curing agent are mixed and stirred according to the optimal mass ratio to obtain the resin curing agent.

[0040] Step S2012, the measured cuttings are placed in the mold and poured into the resin curing agent for stirring, and the measured cuttings are completely covered by the resin curing agent.

[0041] Specifically, the surface moisture of the measured cuttings is dried, the measured cuttings are placed in the quality peeled mold for bearing, to avoid additional errors caused by multiple transfers of the measured cuttings, the mass of the measured cuttings is measured and recorded as m0, the measured cuttings are placed in the mold, a cylindrical mold can be selected for easy measurement, and then the mixed resin curing agent is poured and stirred to make the measured cuttings fully mix and contact with the resin curing agent, while ensuring that the resin curing agent completely covers the measured cuttings, so as to facilitate the subsequent accurate measurement of the volume of the measured sample.

[0042] Step S2013, after the resin curing agent solidifies, the measured sample is formed.

[0043] Specifically, after the resin curing agent solidifies, the prepared measured sample is taken out of the mold, the mass of the measured sample is measured and recorded as m1, and the volume V1 of the measured sample is measured. The density balance can be selected to measure the volume of the measured sample, which is only an example and is not limited thereto.

[0044] In some optional embodiments, after the resin curing agent solidifies, the edge with bubbles and the excess part are polished off with sandpaper to obtain a standard shape of the measured sample.

[0045] Specifically, after the measured sample is completely cured, the part with bubbles on the upper edge (corresponding to the exposed position of the upper mold) and the excess part attached to the bottom edge (corresponding to the bottom of the mold) are polished off with sandpaper to ensure the accuracy of the volume measurement.

[0046] The method for measuring the porosity of rock debris based on nuclear magnetic resonance provided in the embodiment determines the optimal mass ratio of resin and curing agent through experiments, reduces the amount of bubbles and the maximum hardness after solidification, reduces the measurement error, and optimizes the to-be-measured sample after solidification by polishing and removing the excess part, thereby ensuring the accuracy of the volume measurement of the to-be-measured sample.

[0047] Specifically, the apparent volume of the to-be-measured rock debris is calculated based on the to-be-measured sample and the resin curing agent in the step S201, which includes the following steps. In the step S2014, the mass of the to-be-measured sample, the mass of the to-be-measured rock debris, the mass of the resin curing agent are obtained, and the volume of the resin curing agent is calculated based on the density of the resin curing agent.

[0048] Specifically, as known from the steps S2011-S2013, the mass of the to-be-measured sample is m1, the mass of the to-be-measured rock debris is m0, and the volume of the to-be-measured sample is V1. Since the to-be-measured sample is composed of the to-be-measured rock debris and the resin curing agent, the mass of the resin curing agent in the to-be-measured sample is m2=m1-m0, and the units of m0, m1 and m2 are all g. Since the mass ratio of resin to curing agent in the resin curing agent is fixed, the density p of the resin curing agent is considered to be known and fixed, which can be measured by using a density balance or the like. The measurement process is a mature prior art, and thus will not be described herein. According to the formula relationship among mass, density and volume, the volume of the resin curing agent is V2=m2 / p.

[0049] In the step S2015, the volume of the to-be-measured sample is obtained, and the apparent volume of the to-be-measured rock debris is determined based on the volume of the resin curing agent.

[0050] Specifically, since the to-be-measured sample is composed of the resin curing agent and the to-be-measured rock debris, the apparent volume V0 of the to-be-measured rock debris is V1-V2, and the units of V0, V1 and V2 are all g / cm 3 . The to-be-measured rock debris usually has a small volume, and thus the measurement by using a density balance is not accurate. Therefore, the total volume of the to-be-measured sample and the volume of the resin curing agent are used to indirectly calculate and determine the apparent volume of the to-be-measured rock debris, so that the apparent volume of the to-be-measured rock debris is more accurate.

[0051] The method for measuring the porosity of rock debris based on nuclear magnetic resonance provided in the embodiment calculates the volume of the resin curing agent by using the known mass and density of the resin curing agent, reduces the error of volume measurement by using the certainty of the physical formula, determines the apparent volume of the rock debris based on the volume of the to-be-measured sample and the volume of the resin curing agent, improves the accuracy of the calculation of the apparent volume of the rock debris, and further provides more accurate data support for the subsequent analysis of the related characteristics of the rock debris.

[0052] In the step S202, the mass of the resin curing agent in the to-be-measured sample, the first calibration coefficient of the mass of the resin curing agent and the amount of nuclear magnetic resonance signal are obtained, and the first signal component of the resin curing agent in the to-be-measured sample is calculated based on the mass of the resin curing agent and the first calibration coefficient.

[0053] Specifically, the step S202 comprises: In step S2021, the mass of the resin curing agent sample and the corresponding NMR signal amount are obtained, and a first calibration coefficient is determined based on the mass of the resin curing agent sample and the corresponding NMR signal amount.

[0054] Specifically, the resin curing agent sample with a mass of m and a volume of V is placed in a dry sample tube of the NMR instrument, and the NMR signal amount S thereof is measured, and then a first calibration coefficient of the mass and the NMR signal amount is obtained: K = S / m, wherein K represents the first calibration coefficient of the mass of the resin curing agent and the NMR signal amount, the unit is 1 / g, S represents the NMR signal amount of the resin curing agent sample, the unit is dimensionless, and m represents the mass of the resin curing agent sample, the unit is g.

[0055] In step S2022, the mass of the resin curing agent in the sample to be measured is multiplied by the first calibration coefficient to obtain the first signal component of the resin curing agent in the sample to be measured.

[0056] Specifically, the mass m2 of the resin curing agent in the sample to be measured is multiplied by the first calibration coefficient to obtain the first signal component S2 contributed by the resin curing agent in the sample to be measured.

[0057] In step S203, the total NMR signal amount of the sample to be measured is obtained, and the second signal component of the rock debris to be measured in the sample to be measured is determined in combination with the first signal component of the resin curing agent in the sample to be measured.

[0058] Specifically, the step S203 comprises: The total NMR signal amount of the sample to be measured is subtracted from the first signal component of the resin curing agent in the sample to be measured to obtain the second signal component of the rock debris to be measured in the sample to be measured.

[0059] Specifically, the sample to be measured is placed in a dry sample tube of the NMR instrument, and the NMR signal amount S1 thereof is measured, and in combination with the first signal component S2 of the resin curing agent in the sample to be measured, the second signal component S0 contributed by the rock debris can be obtained: S0 = S1-S2.

[0060] The method for measuring rock debris porosity based on NMR provided in the embodiment determines the first calibration coefficient by obtaining the mass of the resin curing agent sample and the corresponding NMR signal amount, accurately establishes the corresponding relationship between the mass of the resin curing agent and the signal amount, and then accurately calculates the first signal component of the resin curing agent in the sample to be measured. The second signal component of the rock debris to be measured can be effectively separated by subtracting the first signal component from the total NMR signal amount of the sample to be measured, the rock debris signal measurement error caused by the interference of the resin curing agent signal is reduced, and the reliability of subsequent analysis is ensured.

[0061] Step S204, obtaining a second calibration coefficient of water volume and NMR signal amount, and calculating the porosity of the measured rock debris based on the second signal component.

[0062] Specifically, the step S204 includes: Step S2041, obtaining the volume of the water standard sample and the corresponding NMR signal amount, and obtaining the second calibration coefficient based on the volume of the water standard sample and the corresponding NMR signal amount.

[0063] Specifically, the pore volume of the rock debris is calculated by the NMR signal amount generated by the fluid (usually water) in the pores thereof. Water is a typical hydrogen nucleus (H) source in the pores, and the NMR signal strength has a linear relationship with the volume. A sealed water standard sample with a known water volume V water is placed in the dry sample tube of the NMR instrument, and the NMR signal amount thereof is measured as S water , and the second calibration coefficient is obtained based on the volume of the water standard sample and the corresponding NMR signal amount: K water =S water / V water , wherein K water is the calibration coefficient of water volume and NMR signal amount, and the unit is 1 / cm 3 ; S water is the NMR signal amount of the volume calibration standard sample, and the unit is dimensionless; V water is the volume of the volume calibration standard sample, and the unit is cm 3 .

[0064] Step S2042, dividing the second signal component by the second calibration coefficient to obtain the pore volume of the measured rock debris.

[0065] Specifically, the contribution of the measured rock debris to the signal amount is relatively low, so the second signal component does not consider the signal contribution of the measured rock debris, and it is assumed that the second signal component is entirely generated by the water in the pores of the measured rock debris. The pore volume of the measured rock debris is calculated according to the second signal component S0 contributed by the measured rock debris and the second calibration coefficient: V por =S0 / K water , wherein V por represents the pore volume of the measured rock debris in the measured sample, and the unit is cm 3 .

[0066] Step S2043, obtaining the porosity of the measured rock debris based on the pore volume and the apparent volume of the measured rock debris.

[0067] Specifically, the porosity of the measured rock debris is calculated based on the pore volume V por and the apparent volume V0 of the measured rock debris: φ=V por / V0×100%, wherein φ represents the porosity, and the unit is %.

[0068] The method for measuring the porosity of the rock debris based on the nuclear magnetic resonance provided in the embodiment determines the second calibration coefficient by acquiring the volume of the water standard sample and the corresponding nuclear magnetic resonance signal amount, accurately establishes the corresponding relationship between the water volume and the nuclear magnetic resonance signal amount, and calculates the pore volume by combining the second signal component with the second calibration coefficient, so as to reduce the error caused by the inaccurate corresponding relationship between the signal and the volume, make the pore volume calculation more accurate, and further improve the accuracy of the porosity calculation.

[0069] In one specific embodiment, the specific steps for measuring the porosity of the rock debris in the laboratory include: (1) Four sandstone rock debris samples saturated with distilled water are selected, the water on the surface of the samples is dried and weighed, and then the samples are placed in a mold, a resin curing agent is prepared according to the optimal mass ratio, poured into the mold, mixed and stirred, and then placed to obtain the samples as shown in Figure 3 After the resin curing agent solidifies, the samples are taken out and weighed, and the volumes of the four samples are measured by using a density balance.

[0070] (2) The resin curing agent sample with a known mass prepared in advance is placed in an NMR instrument to measure the NMR signal; the four samples in step (1) are placed in the NMR instrument to measure the NMR signal.

[0071] (3) The porosity of the samples is calculated, and the measurement results are arranged as shown in Table 1.

[0072] Table 1 Measurement results of the porosity of the rock debris samples

[0073] The results show that the relative error between the porosity of the rock debris measured based on the nuclear magnetic resonance provided in the embodiment and the porosity obtained by the weighing method is within 3%, and the overall test results meet the actual application requirements.

[0074] In the embodiment, an apparatus for measuring the porosity of the rock debris based on the nuclear magnetic resonance is also provided, which is used to implement the above-mentioned embodiments and preferred embodiments, and will not be described again. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware is also possible and contemplated.

[0075] The embodiment provides an apparatus for measuring the porosity of the rock debris based on the nuclear magnetic resonance, as shown in Figure 4 , which comprises: The sample preparation module 401 is configured to prepare a to-be-measured sample by using to-be-measured rock debris and a resin curing agent, and calculate the apparent volume of the to-be-measured rock debris based on the to-be-measured sample and the resin curing agent.

[0076] The first signal component calculation module 402 is configured to obtain resin curing agent quality in the sample to be measured, a first calibration coefficient of the resin curing agent quality and the nuclear magnetic resonance signal amount, and calculate the first signal component of the resin curing agent in the sample to be measured based on the resin curing agent quality and the first calibration coefficient.

[0077] The second signal component calculation module 403 is configured to obtain the total amount of the nuclear magnetic resonance signal of the sample to be measured, and determine the second signal component of the rock debris to be measured in the sample to be measured in combination with the first signal component of the resin curing agent in the sample to be measured.

[0078] The porosity calculation module 404 is configured to obtain a second calibration coefficient of the water volume and the nuclear magnetic resonance signal amount, and calculate the porosity of the rock debris to be measured based on the second signal component.

[0079] In some optional embodiments, the sample preparation module 401 comprises: The resin curing agent preparation unit is configured to determine the optimal mass ratio of resin and curing agent through experimental tests, and mix and stir the resin and the curing agent based on the optimal mass ratio to obtain the resin curing agent.

[0080] The rock debris covering unit is configured to put the rock debris to be measured into a mold, pour the resin curing agent into the mold for stirring, and cover the rock debris to be measured with the resin curing agent.

[0081] The sample solidification unit is configured to form the sample to be measured after the resin curing agent is solidified.

[0082] The resin curing agent volume calculation unit is configured to obtain the mass of the sample to be measured and the mass of the rock debris to be measured, determine the mass of the resin curing agent, and calculate the volume of the resin curing agent based on the density of the resin curing agent.

[0083] The apparent volume calculation unit of the rock debris to be measured is configured to obtain the volume of the sample to be measured, and determine the apparent volume of the rock debris to be measured based on the volume of the resin curing agent.

[0084] In some optional embodiments, the first signal component calculation module 402 comprises: The first calibration coefficient measurement unit is configured to obtain the mass of the resin curing agent standard sample and the corresponding nuclear magnetic resonance signal amount, and determine the first calibration coefficient based on the mass of the resin curing agent standard sample and the corresponding nuclear magnetic resonance signal amount.

[0085] The first signal component calculation unit is configured to multiply the mass of the resin curing agent in the sample to be measured by the first calibration coefficient to obtain the first signal component of the resin curing agent in the sample to be measured.

[0086] In some optional embodiments, the second signal component calculation module 403 comprises: The second signal component calculation unit is configured to subtract the first signal component of the resin curing agent in the sample to be measured from the total nuclear magnetic resonance signal of the sample to be measured, to obtain a second signal component of the rock debris to be measured in the sample to be measured.

[0087] In some optional embodiments, the porosity calculation module 404 comprises: The second calibration coefficient measurement unit is configured to obtain the volume of the water standard sample and the corresponding nuclear magnetic resonance signal amount, and obtain the second calibration coefficient based on the volume of the water standard sample and the corresponding nuclear magnetic resonance signal amount.

[0088] The pore volume calculation unit is configured to divide the second signal component by the second calibration coefficient to obtain the pore volume of the rock debris to be measured.

[0089] The porosity determination unit is configured to obtain the porosity of the rock debris to be measured based on the pore volume and the apparent volume of the rock debris to be measured.

[0090] Further function descriptions of the above-mentioned various modules and units are the same as those of the above-mentioned corresponding embodiments, and will not be described here again.

[0091] In the present embodiment, the device for measuring the porosity of rock debris based on nuclear magnetic resonance is presented in the form of functional units. Here, the units refer to ASIC (Application Specific Integrated Circuit, Application Specific Integrated Circuit) circuits, processors and memories executing one or more software or fixed programs, and / or other devices that can provide the above-mentioned functions.

[0092] The present embodiment also provides a computer device having the above-mentioned Figure 4 device for measuring the porosity of rock debris based on nuclear magnetic resonance.

[0093] Please refer to Figure 5 , Figure 5 is a structural schematic diagram of a computer device provided by an optional embodiment of the present application, as shown in Figure 5As shown, the computer device includes one or more processors 10, memory 20, and interfaces 30 for external devices such as a keyboard and a mouse and peripheral devices such as disk devices or other storage devices. One or more busses 10 can be used to implement the interface between the various internal and external components and can be implemented using any one or more of a variety of bus technologies including a System bus, PCI, SCSI, AGP, Super- I / O bus, etc. Furthermore, various buses can be used in front side buses, back side buses, and other bus configurations based on any bus or messaging technology known to those skilled in the art. Figure 5 The processor 10 is used in the embodiments below as an example.

[0094] The processor 10 can be a central processing unit, a network processor, or a combination thereof. The processor 10 can further include a hardware chip. The hardware chip can be an application specific integrated circuit, a programmable logic device, or a combination thereof. The programmable logic device can be a complex programmable logic device, a field programmable logic device, a general array logic, or any combination thereof.

[0095] The memory 20 stores instructions that can be executed by the at least one processor 10, so that the at least one processor 10 implements the method shown in the above embodiments.

[0096] The memory 20 can include a program region and a data region. The program region can store an operating system and an application program required by at least one function. The data region can store data created according to the use of the computer device, etc. In addition, the memory 20 can include a high-speed random access memory, and can further include a non-transitory memory such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state memory device. In some alternative embodiments, the memory 20 can optionally include a memory disposed remotely with respect to the processor 10, and these remote memories can be connected to the computer device through a network. Examples of the network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0097] The memory 20 can include a volatile memory such as a random access memory, and can also include a non-volatile memory such as a flash memory, a hard disk, or a solid state disk. The memory 20 can further include a combination of the above-mentioned kinds of memories.

[0098] The computer device further includes a communication interface 30 for communication with other devices or communication networks.

[0099] The embodiments of the present application further provide a computer readable storage medium, and the method according to the embodiments of the present application can be implemented in hardware, firmware, or recorded in a storage medium, or be implemented as computer codes stored in a remote storage medium or a non-transitory machine readable storage medium and downloaded through a network and stored in a local storage medium, so that the method described herein can be processed by such software on a storage medium using a general purpose computer, a special purpose processor, or programmable or special hardware. The storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, or a solid state disk, etc. Further, the storage medium can also include a combination of the above-mentioned types of memories. It can be understood that the computer, the processor, the microprocessor controller, or the programmable hardware includes a storage component that can store or receive software or computer codes, when the software or computer codes are accessed and executed by the computer, the processor, or the hardware, the method shown in the above embodiments is implemented.

[0100] Although the embodiments of the present application are described in conjunction with the accompanying drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A method for measuring the porosity of rock cuttings based on nuclear magnetic resonance, characterized in that, The method includes: The test sample was prepared using rock cuttings and resin curing agent, and the apparent volume of the rock cuttings was calculated based on the test sample and resin curing agent. The mass of the resin curing agent in the sample to be tested, the first calibration coefficient of the mass of the resin curing agent and the nuclear magnetic resonance signal quantity are obtained, and the first signal component of the resin curing agent in the sample to be tested is calculated based on the mass of the resin curing agent and the first calibration coefficient. The total nuclear magnetic resonance signal of the sample to be tested is obtained, and combined with the first signal component of the resin curing agent in the sample to be tested, the second signal component of the rock fragments to be tested in the sample to be tested is determined. The second calibration coefficient of water volume and nuclear magnetic resonance signal quantity is obtained, and the porosity of the rock cuttings to be tested is calculated based on the second signal component.

2. The method according to claim 1, characterized in that, The preparation of the test sample using rock fragments and a resin curing agent includes: The optimal mass ratio of resin to curing agent was determined through experimental testing, and the resin and curing agent were mixed and stirred based on the optimal mass ratio to obtain the resin curing agent. The rock fragments to be tested are placed in a mold, and the resin curing agent is poured in and stirred until the rock fragments to be tested are completely covered by the resin curing agent. After the resin curing agent solidifies, the sample to be tested is formed.

3. The method according to claim 2, characterized in that, After the resin curing agent solidifies, sand off any air bubbles and excess material on the edges to obtain a standard-shaped test sample.

4. The method according to claim 1, characterized in that, The apparent volume of the rock cuttings to be tested was calculated based on the sample and the resin curing agent, including: Obtain the mass of the sample to be tested and the mass of the rock cuttings to be tested, determine the mass of the resin curing agent, and calculate the volume of the resin curing agent based on the density of the resin curing agent; Obtain the volume of the sample to be tested, and determine the apparent volume of the rock cuttings to be tested based on the volume of the resin curing agent.

5. The method according to claim 4, characterized in that, Obtain the mass of the resin curing agent in the sample to be tested, the first calibration coefficient of the resin curing agent mass and the nuclear magnetic resonance signal quantity, and calculate the first signal component of the resin curing agent in the sample to be tested based on the resin curing agent mass and the first calibration coefficient, including: The mass of the resin curing agent standard sample and the corresponding nuclear magnetic resonance signal quantity are obtained, and a first calibration coefficient is determined based on the mass of the resin curing agent standard sample and the corresponding nuclear magnetic resonance signal quantity. The first signal component of the resin curing agent in the sample to be tested is obtained by multiplying the mass of the resin curing agent in the sample to be tested by the first scale coefficient.

6. The method according to claim 1 or 5, characterized in that, Obtain the total nuclear magnetic resonance signal of the sample to be tested, and combine it with the first signal component of the resin curing agent in the sample to be tested to determine the second signal component of the rock cuttings in the sample to be tested, including: The total nuclear magnetic resonance signal of the sample to be tested is subtracted from the first signal component of the resin curing agent in the sample to be tested to obtain the second signal component of the rock fragments to be tested in the sample to be tested.

7. The method according to claim 1, characterized in that, Obtaining a second calibration coefficient for the water volume and nuclear magnetic resonance signal quantity, and calculating the porosity of the rock cuttings to be tested based on the second signal component, includes: The volume of the water sample and the corresponding nuclear magnetic resonance signal are obtained, and a second calibration coefficient is obtained based on the volume of the water sample and the corresponding nuclear magnetic resonance signal. Divide the second signal component by the second scale coefficient to obtain the pore volume of the rock cuttings to be tested; The porosity of the rock cuttings is obtained based on their pore volume and apparent volume.

8. A device for measuring the porosity of rock cuttings based on nuclear magnetic resonance, characterized in that, The device includes: The sample preparation module is used to prepare the sample using rock cuttings and resin curing agent, and to calculate the apparent volume of the rock cuttings based on the sample and resin curing agent. The first signal component calculation module is used to obtain the mass of the resin curing agent in the sample to be tested, the first calibration coefficient of the resin curing agent mass and the nuclear magnetic resonance signal, and calculate the first signal component of the resin curing agent in the sample to be tested based on the resin curing agent mass and the first calibration coefficient. The second signal component calculation module is used to obtain the total nuclear magnetic resonance signal of the sample to be tested, and combine it with the first signal component of the resin curing agent in the sample to be tested to determine the second signal component of the rock fragments to be tested in the sample to be tested. The porosity calculation module is used to obtain the second scale coefficient of water volume and nuclear magnetic resonance signal quantity, and to calculate the porosity of the rock cuttings to be tested based on the second signal component.

9. A computer device, characterized in that, include: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the method of any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method of any one of claims 1 to 7.

Images