Method, device and system for testing apparent density of coal sample

Abstract

The embodiment of the invention relates to a coal sample apparent density testing method, device and system. A first valve between a sample bin and a reference bin is opened, and a pressure sensor obtains environment pressure; closing the first valve, putting the sealed sample bag loaded with the coal sample into a sample bin, and filling inert gas into the sample bin to obtain first balance pressure corresponding to the sample bin; opening the first valve, and obtaining second balance pressure corresponding to the sample bin and the reference bin; inputting the sample bin volume, the reference bin volume, the environment pressure, the first balance pressure and the second balance pressure into a preset relational expression to obtain a first volume corresponding to the sealed sample bag loaded with the coal sample; obtaining a second volume corresponding to the sealed sample bag which is not loaded with the coal sample through similar operation steps; determining the apparent density of the coal sample according to the weight of the coal sample, the first volume and the second volume; the apparent density of solid samples such as coal can be tested in a lossless and pollution-free mode, the testing process is simple and rapid, and the shape, density and the like of the tested samples are not limited.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coalbed methane development and utilization, and particularly relates to a coal sample apparent density testing method, device and system. BACKGROUND

[0002] Coalbed methane is a new clean energy, and its development and utilization is of great significance for environmental protection and energy supply pressure relief.

[0003] The apparent density of coal is a necessary parameter for calculating the reserves of coalbed methane. The commonly used testing method is the drainage method, but this method is suitable for samples with apparent density greater than water, and the sample needs to be wax-sealed during the testing process. However, due to the very small pores of coal, a thin film will be attached to the surface of the sample after dewaxing, making it difficult to saturate with gas and water, and making it difficult to use the sample again for other parameter testing and simulation experiments, and it is difficult to realize one-to-one control experiments of the sample. In addition, the apparent density of some low-rank coal is less than water, and the drainage method cannot measure the apparent density. SUMMARY

[0004] The present application provides a coal sample apparent density testing method, device and system to solve the technical problem of how to realize non-destructive and non-polluting testing of the apparent density of coal samples.

[0005] In a first aspect, the present application provides a coal sample apparent density testing method applied to a coal sample apparent density testing device, wherein the coal sample apparent density testing device comprises a pressure sensor, a sample bin and a reference bin, the pressure sensor is arranged on the sample bin, the sample bin and the reference bin are connected through a communication pipeline, and a first valve is arranged on the communication pipeline; the method comprises the following steps: opening the first valve, obtaining the environmental pressure corresponding to the sample bin and the reference bin based on the pressure sensor; closing the first valve, placing a sealed sample bag loaded with coal samples into the sample bin, filling the sample bin with inert gas, and obtaining the first equilibrium pressure corresponding to the sample bin based on the pressure sensor; opening the first valve, obtaining the second equilibrium pressure corresponding to the sample bin and the reference bin based on the pressure sensor; inputting the sample bin volume, the reference bin volume, the environmental pressure, the first equilibrium pressure and the second equilibrium pressure into a preset relationship formula to obtain the first volume corresponding to the sealed sample bag loaded with coal samples; closing the first valve, placing a sealed sample bag not loaded with coal samples into the sample bin, filling the sample bin with inert gas, and obtaining the third equilibrium pressure corresponding to the sample bin based on the pressure sensor; opening the first valve, obtaining the fourth equilibrium pressure corresponding to the sample bin and the reference bin based on the pressure sensor; inputting the sample bin volume, the reference bin volume, the environmental pressure, the third equilibrium pressure and the fourth equilibrium pressure into the preset relationship formula to obtain the second volume corresponding to the sealed sample bag not loaded with coal samples; and determining the apparent density of the coal samples according to the weight, the first volume and the second volume of the coal samples.

[0006] In some embodiments, the coal sample apparent density testing device further comprises a standard ball, and after the first valve is opened and the pressure sensor obtains the ambient pressure corresponding to the sample chamber and the reference chamber, the method further comprises: closing the first valve, placing the standard ball into the sample chamber, flushing the sample chamber with inert gas, and obtaining a fifth equilibrium pressure corresponding to the sample chamber based on the pressure sensor; opening the first valve, obtaining a sixth equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor; inputting the sample chamber volume, the reference chamber volume, the ambient pressure, the fifth equilibrium pressure, and the sixth equilibrium pressure into a preset relationship to obtain a standard ball volume; and when the standard ball volume is within a preset error range, performing the steps of closing the first valve, placing a sealed sample bag loaded with a coal sample into the sample chamber, flushing the sample chamber with inert gas, and obtaining a first equilibrium pressure corresponding to the sample chamber based on the pressure sensor.

[0007] In some embodiments, the coal sample apparent density testing device further comprises a gas source connected to the sample chamber through a gas inlet pipeline, and a second valve is arranged on the gas inlet pipeline; and the method further comprises: opening the second valve, and flushing the sample chamber with inert gas from the gas source through the gas inlet pipeline; and closing the second valve.

[0008] In some embodiments, the coal sample apparent density testing device further comprises an exhaust pipeline arranged on the reference chamber, and a third valve arranged on the exhaust pipeline; and before the first valve is opened and the pressure sensor obtains the ambient pressure corresponding to the sample chamber and the reference chamber, the method further comprises: repeatedly performing the following steps a preset number of times until the standard ball volume is within a preset error range: opening the second valve, flushing the sample chamber with inert gas from the gas source through the gas inlet pipeline; closing the second valve, opening the first valve, and allowing inert gas to enter the reference chamber from the sample chamber; closing the first valve, opening the third valve, and allowing inert gas to be discharged from the exhaust pipeline of the reference chamber.

[0009] In some embodiments, the preset relationship is as follows:

[0010]

[0011] wherein V samp represents the volume of a target object, the target object being one of a sealed sample bag loaded with a coal sample, a sealed sample bag not loaded with a coal sample, and a standard ball; V cell represents the sample chamber volume; V exp represents the reference chamber volume; P x represents the equilibrium pressure corresponding to the sample chamber when the target object is placed in the sample chamber; P y represents the equilibrium pressure corresponding to the sample chamber and the reference chamber when the first valve is opened; P a represents the ambient pressure.

[0012] In the second aspect, the present application provides a coal sample apparent density testing device, comprising: a control device, a pressure sensor, a sample bin and a reference bin, the pressure sensor is arranged on the sample bin, the sample bin and the reference bin are connected through a communication pipeline, and a first valve is arranged on the communication pipeline; the control device is used for controlling to execute the following steps: opening the first valve, obtaining the corresponding environmental pressures of the sample bin and the reference bin based on the pressure sensor; closing the first valve, putting a sealed sample bag loaded with a coal sample into the sample bin, filling inert gas into the sample bin, obtaining the corresponding first equilibrium pressure of the sample bin based on the pressure sensor; opening the first valve, obtaining the corresponding second equilibrium pressure of the sample bin and the reference bin based on the pressure sensor; inputting the volume of the sample bin, the volume of the reference bin, the environmental pressure, the first equilibrium pressure and the second equilibrium pressure into a preset relationship formula to obtain the first volume corresponding to the sealed sample bag loaded with the coal sample; closing the first valve, putting a sealed sample bag not loaded with a coal sample into the sample bin, filling inert gas into the sample bin, obtaining the corresponding third equilibrium pressure of the sample bin based on the pressure sensor; opening the first valve, obtaining the corresponding fourth equilibrium pressure of the sample bin and the reference bin based on the pressure sensor; inputting the volume of the sample bin, the volume of the reference bin, the environmental pressure, the third equilibrium pressure and the fourth equilibrium pressure into a preset relationship formula to obtain the second volume corresponding to the sealed sample bag not loaded with a coal sample; and determining the apparent density of the coal sample according to the weight, the first volume and the second volume of the coal sample.

[0013] In some embodiments, a standard ball is further included; the control device is further used for controlling to execute the following steps: closing the first valve, putting the standard ball into the sample bin, filling inert gas into the sample bin, obtaining the corresponding fifth equilibrium pressure of the sample bin based on the pressure sensor; opening the first valve, obtaining the corresponding sixth equilibrium pressure of the sample bin and the reference bin based on the pressure sensor; inputting the volume of the sample bin, the volume of the reference bin, the environmental pressure, the fifth equilibrium pressure and the sixth equilibrium pressure into a preset relationship formula to obtain the volume of the standard ball; and in the case that the volume of the standard ball is within a preset error range, controlling to execute the steps of closing the first valve, putting the sealed sample bag loaded with the coal sample into the sample bin, filling inert gas into the sample bin, and obtaining the corresponding first equilibrium pressure of the sample bin based on the pressure sensor.

[0014] In some embodiments, a gas source is further included, the gas source is connected with the sample bin through a gas inlet pipeline, a second valve is arranged on the gas inlet pipeline; and the control device is specifically used for controlling to execute the following steps: opening the second valve, filling inert gas into the sample bin based on the gas source through the gas inlet pipeline; and closing the second valve.

[0015] In some embodiments, the control device is further configured to, before opening the first valve and obtaining the ambient pressures of the sample chamber and the reference chamber based on the pressure sensor, control the following steps to be repeatedly performed for a preset number of times until the volume of the standard sphere is within a preset error range: opening the second valve, filling the inert gas into the sample chamber through the gas inlet pipeline based on the gas source; closing the second valve, opening the first valve, and allowing the inert gas to enter the reference chamber from the sample chamber; closing the first valve, opening the third valve, and allowing the inert gas to be discharged from the exhaust pipeline of the reference chamber.

[0016] In a third aspect, the present application provides a coal sample apparent density testing system, comprising the coal sample apparent density testing device and the sealing device according to any one of the second aspect, the sealing device comprising a sealed sample bag and a sealing machine; the sealed sample bag is used for loading the coal sample, and the sealing machine is used for vacuum sealing the sealed sample bag.

[0017] The coal sample apparent density testing method, device and system provided by the embodiments of the present application can realize non-destructive and non-polluting testing of the apparent density of solid samples such as coal, and the testing process is simple and fast, and has no limitation on the shape and density of the test sample. BRIEF DESCRIPTION OF DRAWINGS

[0018] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present application and, together with the specification, serve to explain the principles of the application.

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, for those skilled in the art, other drawings can also be obtained based on these drawings without creative labor.

[0020] Figure 1 A structural schematic diagram of a coal sample apparent density testing system provided by the embodiments of the present application;

[0021] Figure 2 A flowchart of a coal sample apparent density testing method provided by the embodiments of the present application;

[0022] Figure 3 A flowchart of another coal sample apparent density testing method provided by the embodiments of the present application;

[0023] 10-Coal sample apparent density testing device; 101-Pressure sensor; 102-Sample chamber; 1021-Sample chamber cover; 103-Reference chamber; 104-Connecting pipeline; 105-First valve; 106-Gas source; 107-Inlet pipeline; 108-Second valve; 109-Exhaust pipeline; 110-Third valve; 20-Sealing device; 201-Sealed sample bag; 202-Sealing machine; 203-Coal sample. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Figure 1 This is a schematic diagram of the structure of a coal sample apparent density testing system provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the apparent density testing system for tube coal samples includes: a coal sample apparent density testing device 10 and a sealing device 20, wherein the coal sample apparent density testing device 10 includes a control device ( Figure 1 (omitted) , pressure sensor 101, sample chamber 102 and reference chamber 103, pressure sensor 101 is mounted on sample chamber 102, sample chamber 102 has an openable sample chamber cover 1021, sample chamber 102 and reference chamber 103 are connected by a connecting pipeline 104, the connecting pipeline 104 is equipped with a first valve 105; the coal sample apparent density testing device 10 also includes a gas source 106, the gas source 106 provides an inert gas, such as helium; the gas source 106 is connected to sample chamber 102 through an inlet pipeline 107, the inlet pipeline 107 is equipped with a second valve 108; the coal sample apparent density testing device 10 also includes an exhaust pipeline 109 mounted on reference chamber 103, and a third valve 110 mounted on exhaust pipeline 109; the coal sample apparent density testing device 10 also includes a standard sphere ( Figure 1 omitted)

[0026] The sealing device 20 includes a sealed sample bag 201 and a sealing machine 202. The sealed sample bag 201 is used to load the coal sample 203, and the sealing machine 202 is used to vacuum seal the sealed sample bag 201.

[0027] It should be noted that, Figure 1 The control equipment in the coal sample apparent density testing system shown can be used to control the coal sample apparent density testing method performed in the following embodiments. Figure 1 The coal sample apparent density testing system shown can be used to perform the coal sample apparent density testing methods described in the following embodiments.

[0028] Figure 2 A flowchart of a coal sample apparent density testing method provided by an embodiment of the present application is shown in FIG. 1. As shown in the figure, the method comprises the following steps. Figure 2

[0029] Step S201: open the first valve, and obtain the ambient pressure corresponding to the sample bin and the reference bin based on the pressure sensor.

[0030] Specifically, after purging the sample bin 102 and the reference bin, the first valve 105 is opened to connect the sample bin 102 and the reference bin 103, and the pressure sensor 101 is used to measure the ambient pressure P0 at this time. a .

[0031] Step S202: close the first valve, put the sealed sample bag loaded with coal sample into the sample bin, fill the sample bin with inert gas, and obtain the first equilibrium pressure corresponding to the sample bin based on the pressure sensor.

[0032] Step S203: open the first valve, and obtain the second equilibrium pressure corresponding to the sample bin and the reference bin based on the pressure sensor.

[0033] Step S204: input the sample bin volume, the reference bin volume, the ambient pressure, the first equilibrium pressure, and the second equilibrium pressure into a preset relationship formula to obtain the first volume corresponding to the sealed sample bag loaded with coal sample.

[0034] Specifically, the volume V1 corresponding to the sealed sample bag loaded with coal sample is calculated through steps S202-S204. First, the coal sample 203 to be tested is loaded into the sealed sample bag 201, the sealed sample bag 201 is vacuum sealed by using the sealing machine 202 to obtain the sealed sample bag loaded with coal sample, the first valve 105 is controlled to be closed, the sample bin cover 1021 is opened, the sealed sample bag loaded with coal sample is put into the sample bin 102, the sample bin cover 1021 is closed, helium is injected into the sample bin 102, and the pressure sensor 101 records the first equilibrium pressure P1 of the sample bin 102; then, the first valve 105 is controlled to be opened, the sample bin 102 and the reference bin 103 are connected, and the pressure sensor 101 records the system equilibrium pressure corresponding to the sample bin 102 and the reference bin 103, i.e., the second equilibrium pressure P2; finally, the sample bin volume V cell , the reference bin volume V exp , and the measured P a , P1, and P2 are substituted into the preset relationship formula to calculate V1, wherein the preset relationship formula is derived according to the ideal gas state equation.

[0035] ​Step S205, close the first valve, put the sealed sample bag without loading coal sample into the sample bin, fill the inert gas into the sample bin, and obtain the third equilibrium pressure corresponding to the sample bin based on the pressure sensor.

[0036] Step S206, open the first valve, and obtain the fourth equilibrium pressure corresponding to the sample bin and the reference bin based on the pressure sensor.

[0037] Step S207, input the sample bin volume, the reference bin volume, the ambient pressure, the third equilibrium pressure and the fourth equilibrium pressure into the preset relationship formula, and obtain the second volume corresponding to the sealed sample bag without loading coal sample.

[0038] Specifically, the volume V2 of the sealed sample bag without loading coal sample is calculated through steps S205-S207. First, the sealed sample bag with loading coal sample is disassembled to obtain the empty sealed sample bag 201. The first valve 105 is controlled to be closed, the sample bin cover 1021 is opened, the empty sealed sample bag 201 is put into the sample bin 102, the sample bin cover 1021 is closed, helium is filled into the sample bin 102, and the pressure sensor 101 records the third equilibrium pressure P3 of the sample bin 102. Then, the first valve 105 is controlled to be opened, the sample bin 102 and the reference bin 103 are communicated, and the pressure sensor 101 records the system equilibrium pressure corresponding to the sample bin 102 and the reference bin 103, i.e. the fourth equilibrium pressure P4. Finally, V1, V2, P1, P3 and P4 obtained in advance are substituted into the preset relationship formula to calculate V2. cell l, V exp and the measured P a , P3, P4 are substituted into the preset relationship formula to calculate V2.

[0039] Step S208, determine the apparent density of the coal sample according to the weight of the coal sample, the first volume and the second volume.

[0040] Specifically, the disassembled coal sample 203 is dried and weighed, and the mass M1 is recorded. The apparent density of the coal sample 203 is calculated according to formula (1):

[0041]

[0042] Wherein, ρ represents the apparent density of the coal sample, M1 represents the mass of the coal sample, V1 represents the volume of the sealed sample bag with loading coal sample, and V2 represents the volume of the sealed sample bag 201 without loading coal sample.

[0043] In some embodiments, the coal sample apparent density testing device 10 further comprises a gas source 106 connected with the sample chamber 102 through a gas inlet pipeline 107, and a second valve 108 is arranged on the gas inlet pipeline 107; and the step of filling the sample chamber with inert gas in steps S202 and S205 comprises: opening the second valve, filling the sample chamber with inert gas based on the gas source through the gas inlet pipeline, and closing the second valve.

[0044] Specifically, the gas source 106 provides inert gas, such as helium; at this time, the first valve 105 is in a closed state, i.e., the sample chamber 102 and the reference chamber 103 are not connected, the second valve 108 can be opened, the gas source 106 fills the sample chamber 102 with helium through the gas inlet pipeline 107, and after the sample chamber 102 reaches the equilibrium pressure P1 or P3, the second valve 108 is closed.

[0045] In some embodiments, the preset relationship is as follows:

[0046]

[0047] wherein, V samp represents the volume of the target object, which is one of the sealed sample bag loaded with coal sample, the sealed sample bag not loaded with coal sample, and the standard ball; V cell represents the volume of the sample chamber; V exp represents the volume of the reference chamber; P x represents the equilibrium pressure of the sample chamber when the target object is placed in the sample chamber; P y represents the equilibrium pressure of the sample chamber and the reference chamber when the first valve is opened; P a represents the ambient pressure.

[0048] The preset relationship (2) is derived based on the ideal gas state equation, and the ideal gas state equation is as shown in formula (3), and the derivation process is as follows:

[0049] PV = nRT (3)

[0050] First, the ambient pressure P a and the ambient temperature T a when the sample chamber 102 and the reference chamber 103 are connected are determined; then, the target object is placed in the sample chamber 102 under the condition that the first valve 105 is closed, helium is filled into the sample chamber 102, and the equilibrium pressure P x in the sample chamber 102 is recorded, at this time, the pressure of the reference chamber 103 is still P a , the corresponding ideal gas state equation in the sample chamber 102 is as shown in formula (4), and the corresponding ideal gas state equation in the reference chamber 103 is as shown in formula (5):

[0051] Px (V cell -V samp )=n c RT a (4)

[0052] P a V exp =n e RT a (5)

[0053] Then, the first valve 105 between the sample chamber 102 and the reference chamber 103 is opened, the sample chamber 102 and the reference chamber 103 are communicated, and the system equilibrium pressure P y At this time, the ideal gas state equation corresponding to the sample chamber 102 and the reference chamber 103 is as shown in formula (6):

[0054] P y (V cell -V samp +V exp )=n c RT a +n e RT a (6)

[0055] Wherein, n c represents the gas molar number of the sample chamber, and n e represents the gas molar number of the reference chamber. By substituting formula (4) and (5) into formula (6), the volume V samp of the target object can be derived as shown in formula (2).

[0056] Correspondingly, the calculation formula of the volume V1 of the sealed sample bag loaded with the coal sample is as follows:

[0057]

[0058] Correspondingly, the calculation formula of the volume V2 of the sealed sample bag not loaded with the coal sample is as follows:

[0059]

[0060] The coal sample apparent density testing method provided in the embodiment can realize nondestructive and non-polluting testing of the apparent density of the coal sample through the coal sample apparent density testing device, the testing process is simple and fast, and there is no limitation on the shape and density of the tested coal sample; in addition, the embodiment can be applied not only to the apparent density testing of the coal sample, but also to the apparent density testing of other solid samples.

[0061] On the basis of the foregoing embodiment, Figure 3 The flowchart of another coal sample apparent density testing method provided in the embodiment is as follows:Figure 3 as shown, comprising the following steps:

[0062] Step S301, open the first valve, and obtain the ambient pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor.

[0063] Step S302, close the first valve, put the standard ball into the sample chamber, fill the inert gas into the sample chamber, and obtain the fifth equilibrium pressure corresponding to the sample chamber based on the pressure sensor.

[0064] Step S303, open the first valve, and obtain the sixth equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor.

[0065] Step S304, input the sample chamber volume, the reference chamber volume, the ambient pressure, the fifth equilibrium pressure, and the sixth equilibrium pressure into the preset relationship formula to obtain the standard ball volume.

[0066] Step S305, determine whether the standard ball volume is within the preset error range.

[0067] If not, end the embodiment or execute step S306 and return to execute step S301; if yes, execute step S307.

[0068] Step S307, close the first valve, put the sealed sample bag loaded with coal samples into the sample chamber, fill the inert gas into the sample chamber, and obtain the first equilibrium pressure corresponding to the sample chamber based on the pressure sensor.

[0069] Step S308, open the first valve, and obtain the second equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor.

[0070] Step S309, input the sample chamber volume, the reference chamber volume, the ambient pressure, the first equilibrium pressure, and the second equilibrium pressure into the preset relationship formula to obtain the first volume corresponding to the sealed sample bag loaded with coal samples.

[0071] Step S310, close the first valve, put the sealed sample bag not loaded with coal samples into the sample chamber, fill the inert gas into the sample chamber, and obtain the third equilibrium pressure corresponding to the sample chamber based on the pressure sensor.

[0072] Step S311, open the first valve, and obtain the fourth equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor.

[0073] Step S312, input the sample chamber volume, the reference chamber volume, the ambient pressure, the third equilibrium pressure, and the fourth equilibrium pressure into the preset relationship formula to obtain the second volume corresponding to the sealed sample bag not loaded with coal samples.

[0074] Step S313: Determine the apparent density of the coal sample based on its weight, first volume, and second volume.

[0075] It should be noted that steps S301 and S307-S313 in this embodiment are similar to steps S201-S208 in the previous embodiment, and will not be described again here.

[0076] The difference from the previous embodiment is that, in order to further improve the accuracy of the coal sample apparent density test, in this embodiment, the first valve is closed, the standard ball is placed into the sample chamber, inert gas is injected into the sample chamber, and the fifth equilibrium pressure corresponding to the sample chamber is obtained based on the pressure sensor; the first valve is opened, and the sixth equilibrium pressure corresponding to the sample chamber and the reference chamber is obtained based on the pressure sensor; the volume of the sample chamber, the volume of the reference chamber, the ambient pressure, the fifth equilibrium pressure, and the sixth equilibrium pressure are input into a preset formula to obtain the volume of the standard ball; if the volume of the standard ball is within the preset error range, steps S306-S312 are executed; otherwise, the coal sample apparent density testing device 10 is continued to be purged.

[0077] Specifically, before formally testing the coal sample, it is necessary to first use a standard sphere of known volume (V) 标准球 Verify whether the volumes of sample chamber 102 and reference chamber 103 have changed. If no change has occurred, proceed with the test. The verification process is as follows: Record the environmental pressure P. a With the first valve 105 closed, place the standard ball into the sample chamber 102, and fill the sample chamber 102 with helium gas through the gas source 106. Record the fifth equilibrium pressure P5 corresponding to the sample chamber 102. Then, open the valve between the reference chamber 103 and the sample chamber 102, and record the pressure after system equilibrium, i.e., the sixth equilibrium pressure P6. The previously known V... cell l、V exp and the measured P a Substituting P5 and P6 into the preset relation, we obtain V. 标准球 The calculation formula is as follows:

[0078]

[0079] Finally, according to the specifications provided with the standard sphere, check whether the calculated volume of the standard sphere is within the allowable error range. If it is within the allowable error range, the coal sample test can be carried out; if it is not within the allowable error range, the implementation ends, or the environmental pressure of the coal sample apparent density testing device 10 is further adjusted.

[0080] In some embodiments, the coal apparent density testing device 10 further comprises an exhaust pipeline 109 arranged on the reference chamber 103, and a third valve 110 arranged on the exhaust pipeline 109; before the step S301, the method further comprises: repeatedly performing the following steps for a preset number of times until the standard ball volume is within a preset error range: opening the second valve, filling the sample chamber with inert gas from the gas source through the air inlet pipeline; closing the second valve, opening the first valve, and allowing the inert gas to enter the reference chamber from the sample chamber; closing the first valve, opening the third valve, and allowing the inert gas to be discharged from the exhaust pipeline of the reference chamber.

[0081] Specifically, before obtaining the ambient pressure, the coal apparent density testing device 10 needs to be purged to realize zeroing of the pressure sensor 101, where the zero point of the pressure sensor 101 is the atmospheric pressure value, not absolute 0; and the zeroing of the pressure sensor can analyze whether the coal apparent density testing device 10 is leaking. The purging process is as follows: first, open the second valve 108, and the gas source 106 outputs helium to the sample chamber 102, then close the second valve 108, open the first valve 105, and the helium enters the reference chamber 103, open the third valve 110, and the helium is discharged, and the process is repeated 2-3 times to replace and discharge the gas in the sample chamber 102 and the reference chamber 103, so that the residual gas in the chamber is helium; then, whether the standard ball volume is within the error range is used to verify whether the volume of the sample chamber 102 and the reference chamber 103 changes, if the standard ball volume exceeds the error range, the purging process can be continued for 2-3 times, until the standard ball volume is within the error range, and then the apparent density test of the coal sample 203 is performed.

[0082] On the basis of the foregoing embodiments, before testing the apparent density of the coal sample, whether the standard ball of a known volume is within a constraint error range is used to verify whether the volume of the sample chamber and the reference chamber changes, and the coal sample test is performed only when no change occurs, if it is verified that the volume of the sample chamber and the reference chamber changes, the coal apparent density testing device can be continuously purged until the verification is passed, thereby improving the accuracy of the subsequent coal apparent density test.

[0083] The embodiment of the present application also provides a coal apparent density testing device. As shown in the figure, the coal apparent density testing device 10 comprises: Figure 1

[0084] ​The control device, a pressure sensor 101 arranged on the sample bin 102, the sample bin 102 and the reference bin 103 connected through a communication pipeline 104, and a first valve 105 arranged on the communication pipeline 104; the control device is used to control the following steps: opening the first valve 105, obtaining the corresponding ambient pressures of the sample bin 102 and the reference bin 103 based on the pressure sensor 101; closing the first valve 105, placing the sealed sample bag loaded with the coal sample into the sample bin 102, filling the sample bin 102 with inert gas, and obtaining the corresponding first equilibrium pressure of the sample bin 102 based on the pressure sensor 101; opening the first valve 105, obtaining the corresponding second equilibrium pressure of the sample bin 102 and the reference bin 103 based on the pressure sensor 101; inputting the sample bin volume, the reference bin volume, the ambient pressure, the first equilibrium pressure, and the second equilibrium pressure into a preset relationship formula to obtain the corresponding first volume of the sealed sample bag loaded with the coal sample; closing the first valve 105, placing the sealed sample bag not loaded with the coal sample into the sample bin 102, filling the sample bin 102 with inert gas, and obtaining the corresponding third equilibrium pressure of the sample bin 102 based on the pressure sensor 101; opening the first valve 105, obtaining the corresponding fourth equilibrium pressure of the sample bin 102 and the reference bin 103 based on the pressure sensor 101; inputting the sample bin volume, the reference bin volume, the ambient pressure, the third equilibrium pressure, and the fourth equilibrium pressure into a preset relationship formula to obtain the corresponding second volume of the sealed sample bag not loaded with the coal sample; and determining the apparent density of the coal sample according to the weight of the coal sample, the first volume, and the second volume.

[0085] In some embodiments, a standard ball is further included; the control device is further used to control the following steps: closing the first valve 105, placing the standard ball into the sample bin 102, filling the sample bin 102 with inert gas, and obtaining the corresponding fifth equilibrium pressure of the sample bin 102 based on the pressure sensor 101; opening the first valve 105, obtaining the corresponding sixth equilibrium pressure of the sample bin 102 and the reference bin 103 based on the pressure sensor 101; inputting the sample bin volume, the reference bin volume, the ambient pressure, the fifth equilibrium pressure, and the sixth equilibrium pressure into a preset relationship formula to obtain the volume of the standard ball; and in the case that the volume of the standard ball is within a preset error range, controlling the following steps: closing the first valve 105, placing the sealed sample bag loaded with the coal sample into the sample bin 102, filling the sample bin 102 with inert gas, and obtaining the corresponding first equilibrium pressure of the sample bin 102 based on the pressure sensor 101.

[0086] In some embodiments, a gas source 106 is further included, which is connected with the sample chamber 102 through a gas inlet line 107, and a second valve 108 is arranged on the gas inlet line 107; and the control device is specifically configured to control the following steps: opening the second valve 108, and filling the sample chamber 102 with inert gas from the gas source 106 through the gas inlet line 107; and closing the second valve 108.

[0087] In some embodiments, an exhaust line 109 is arranged on the reference chamber 103, and a third valve 110 is arranged on the exhaust line 109; and the control device is further configured to control the following steps before opening the first valve 105 and obtaining the corresponding ambient pressures of the sample chamber 102 and the reference chamber 103 based on the pressure sensor 101: repeating the following steps for a preset number of times until the volume of the standard ball is within a preset error range: opening the second valve 108, and filling the sample chamber 102 with inert gas from the gas source 106 through the gas inlet line 107; closing the second valve 108, opening the first valve 105, and allowing the inert gas to enter the reference chamber 103 from the sample chamber 102; closing the first valve 105, opening the third valve 110, and allowing the inert gas to be exhausted from the exhaust line 109 of the reference chamber 103.

[0088] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the coal sample apparent density testing device described above and the corresponding benefits can refer to the corresponding process in the foregoing method examples, which will not be repeated here.

[0089] The embodiment of the present application further provides a coal sample apparent density testing system, as shown in the accompanying drawings, which comprises: Figure 1

[0090] The coal sample apparent density testing device 10 and the sealing device 20 as described above, the sealing device 20 comprises a sealed sample bag 201 and a sealing machine 202; the sealed sample bag 201 is used for loading a coal sample 203, and the sealing machine 202 is used for vacuum sealing the sealed sample bag 201.

[0091] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the coal sample apparent density testing system described above and the corresponding benefits can refer to the corresponding process in the foregoing method examples, which will not be repeated here.

[0092] ​It has to be noted that, in the present document, relational terms are intended only to convey a possible relationship between elements or

[0093] The foregoing is considered as illustrative only of the principles of the application. Numerous modifications and changes will readily occur to those skilled in the art, which modifications and changes are to be understood as intended to be encompassed by the general scope of the application. Accordingly, the application is not to be limited to the above described or illustrated embodiments that are merely given by way of example. It is also be understood that various combinations of the above described embodiments and variations thereof are encompassed by the application.

Claims

1. A method for testing the apparent density of coal samples, characterized in that, An apparatus for testing the apparent density of coal samples, comprising a pressure sensor, a sample chamber, and a reference chamber, wherein the pressure sensor is mounted on the sample chamber, and the sample chamber and the reference chamber are connected via a connecting pipeline, on which a first valve is installed; the method includes: Open the first valve and obtain the corresponding ambient pressure of the sample chamber and reference chamber based on the pressure sensor; Close the first valve, place the sealed sample bag containing the coal sample into the sample chamber, fill the sample chamber with inert gas, and obtain the first equilibrium pressure corresponding to the sample chamber based on the pressure sensor; Open the first valve and obtain the second equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor; Input the sample chamber volume, reference chamber volume, ambient pressure, first equilibrium pressure and second equilibrium pressure into the preset formula to obtain the first volume corresponding to the sealed sample bag loaded with coal sample. Close the first valve, place the sealed sample bag without coal sample into the sample chamber, fill the sample chamber with inert gas, and obtain the corresponding third equilibrium pressure of the sample chamber based on the pressure sensor; Open the first valve and obtain the fourth equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor; Input the sample chamber volume, reference chamber volume, ambient pressure, third equilibrium pressure and fourth equilibrium pressure into the preset formula to obtain the second volume corresponding to the sealed sample bag without coal sample; The apparent density of the coal sample is determined based on its weight, first volume, and second volume.

2. The method according to claim 1, characterized in that, The coal sample apparent density testing device also includes a standard ball. After opening the first valve and obtaining the corresponding environmental pressures of the sample chamber and reference chamber based on the pressure sensor, the device further includes: Close the first valve, place the standard ball into the sample chamber, and inject inert gas into the sample chamber. Obtain the fifth equilibrium pressure corresponding to the sample chamber based on the pressure sensor. Open the first valve and obtain the sixth equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor; The volume of the sample chamber, the volume of the reference chamber, the ambient pressure, the fifth equilibrium pressure, and the sixth equilibrium pressure are input into a preset formula to obtain the volume of the standard sphere. If the volume of the standard sphere is within the preset error range, the steps of closing the first valve, placing the sealed sample bag containing the coal sample into the sample chamber, filling the sample chamber with inert gas, and obtaining the first equilibrium pressure corresponding to the sample chamber based on the pressure sensor are performed.

3. The method according to claim 2, characterized in that, The coal sample apparent density testing device further includes a gas source, which is connected to the sample chamber via an inlet pipeline, and a second valve is installed on the inlet pipeline; then, the process of filling the sample chamber with inert gas includes: Open the second valve and, based on the gas source, fill the sample chamber with inert gas through the gas inlet pipeline; Close the second valve.

4. The method according to claim 3, characterized in that, The coal sample apparent density testing device also includes an exhaust pipe installed on the reference chamber, and a third valve installed on the exhaust pipe; before opening the first valve and obtaining the corresponding environmental pressures of the sample chamber and the reference chamber based on the pressure sensor, the following steps are also included: Repeat the following steps a preset number of times until the volume of the standard sphere is within a preset error range: Open the second valve and, based on the gas source, fill the sample chamber with inert gas through the gas inlet pipeline; Close the second valve and open the first valve; inert gas enters the reference chamber from the sample chamber. Close the first valve and open the third valve; the inert gas is discharged from the exhaust line of the reference chamber.

5. The method according to claim 2, characterized in that, The preset relation is as follows: Among them, V samp V represents the volume of the target object, which is one of the following: a sealed sample bag containing a coal sample, a sealed sample bag without a coal sample, or a standard sphere; cell V represents the volume of the sample chamber. exp P represents the reference chamber volume; x P represents the equilibrium pressure in the sample chamber when the target object is placed inside; y This indicates the equilibrium pressure between the sample chamber and the reference chamber when the first valve is opened; P a This indicates environmental pressure.

6. A coal sample apparent density testing device, characterized in that, include: The system includes a control device, a pressure sensor, a sample chamber, and a reference chamber. The pressure sensor is mounted on the sample chamber. The sample chamber and the reference chamber are connected via a connecting pipeline, on which a first valve is installed. The control device is used to control the execution of the following steps: Open the first valve and obtain the corresponding ambient pressure of the sample chamber and reference chamber based on the pressure sensor; Close the first valve, place the sealed sample bag containing the coal sample into the sample chamber, fill the sample chamber with inert gas, and obtain the first equilibrium pressure corresponding to the sample chamber based on the pressure sensor; Open the first valve and obtain the second equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor; Input the sample chamber volume, reference chamber volume, ambient pressure, first equilibrium pressure and second equilibrium pressure into the preset formula to obtain the first volume corresponding to the sealed sample bag loaded with coal sample. Close the first valve, place the sealed sample bag without coal sample into the sample chamber, fill the sample chamber with inert gas, and obtain the corresponding third equilibrium pressure of the sample chamber based on the pressure sensor; Open the first valve and obtain the fourth equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor; Input the sample chamber volume, reference chamber volume, ambient pressure, third equilibrium pressure and fourth equilibrium pressure into the preset formula to obtain the second volume corresponding to the sealed sample bag without coal sample; The apparent density of the coal sample is determined based on its weight, first volume, and second volume.

7. The apparatus according to claim 6, characterized in that, It also includes a standard ball; the control device is further used to control the execution of the following steps: Close the first valve, place the standard ball into the sample chamber, and inject inert gas into the sample chamber. Obtain the fifth equilibrium pressure corresponding to the sample chamber based on the pressure sensor. Open the first valve and obtain the sixth equilibrium pressure corresponding to the sample chamber and the reference chamber based on the pressure sensor; The volume of the sample chamber, the volume of the reference chamber, the ambient pressure, the fifth equilibrium pressure, and the sixth equilibrium pressure are input into a preset formula to obtain the volume of the standard sphere. When the volume of the standard sphere is within the preset error range, the system controls the following steps: closing the first valve, placing the sealed sample bag containing the coal sample into the sample chamber, filling the sample chamber with inert gas, and obtaining the first equilibrium pressure corresponding to the sample chamber based on the pressure sensor.

8. The apparatus according to claim 7, characterized in that, It also includes a gas source, which is connected to the sample chamber via an inlet pipeline, and a second valve is installed on the inlet pipeline; the control device is specifically used to control the execution of the following steps: Open the second valve and, based on the gas source, fill the sample chamber with inert gas through the gas inlet pipeline; Close the second valve.

9. The apparatus according to claim 8, characterized in that, It also includes an exhaust pipe installed on the reference chamber, and a third valve installed on the exhaust pipe; then the control device is further configured to control the execution of the following steps before opening the first valve and obtaining the corresponding environmental pressures of the sample chamber and the reference chamber based on the pressure sensor: Repeat the following steps a preset number of times until the volume of the standard sphere is within a preset error range: Open the second valve and, based on the gas source, fill the sample chamber with inert gas through the gas inlet pipeline; Close the second valve and open the first valve; inert gas enters the reference chamber from the sample chamber. Close the first valve and open the third valve; the inert gas is discharged from the exhaust line of the reference chamber.

10. A coal sample apparent density testing system, characterized in that, Includes the coal sample apparent density testing device and sealing device as described in any one of claims 6-9, wherein the sealing device includes a sealing sample bag and a sealing machine; The sealed sample bag is used to load coal samples, and the sealing machine is used to vacuum seal the sealed sample bag.

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