CN110219699B - Device and method for measuring effective influence radius of gas extraction drill hole - Google Patents
Device and method for measuring effective influence radius of gas extraction drill hole Download PDFInfo
- Publication number
- CN110219699B CN110219699B CN201910333945.8A CN201910333945A CN110219699B CN 110219699 B CN110219699 B CN 110219699B CN 201910333945 A CN201910333945 A CN 201910333945A CN 110219699 B CN110219699 B CN 110219699B
- Authority
- CN
- China
- Prior art keywords
- pressure
- gas
- measuring
- coal
- extraction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000605 extraction Methods 0.000 title claims abstract description 67
- 238000000034 method Methods 0.000 title claims abstract description 36
- 239000003245 coal Substances 0.000 claims abstract description 91
- 238000012544 monitoring process Methods 0.000 claims abstract description 23
- 238000012360 testing method Methods 0.000 claims abstract description 12
- 230000000087 stabilizing effect Effects 0.000 claims description 45
- 238000007789 sealing Methods 0.000 claims description 32
- 238000002347 injection Methods 0.000 claims description 19
- 239000007924 injection Substances 0.000 claims description 19
- -1 polytetrafluoroethylene Polymers 0.000 claims description 9
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 9
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 9
- 238000004088 simulation Methods 0.000 claims description 9
- 230000000712 assembly Effects 0.000 claims description 7
- 238000000429 assembly Methods 0.000 claims description 7
- 238000009530 blood pressure measurement Methods 0.000 claims description 5
- 238000005553 drilling Methods 0.000 claims description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 4
- 229910052802 copper Inorganic materials 0.000 claims description 4
- 239000010949 copper Substances 0.000 claims description 4
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 230000008569 process Effects 0.000 abstract description 6
- 230000008859 change Effects 0.000 abstract description 3
- 239000011148 porous material Substances 0.000 abstract description 3
- 230000006872 improvement Effects 0.000 description 10
- 238000010276 construction Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 244000137852 Petrea volubilis Species 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000010835 comparative analysis Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
- E21B49/02—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells by mechanically taking samples of the soil
- E21B49/025—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells by mechanically taking samples of the soil of underwater soil, e.g. with grab devices
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
- E21F17/18—Special adaptations of signalling or alarm devices
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F7/00—Methods or devices for drawing- off gases with or without subsequent use of the gas for any purpose
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Soil Sciences (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
The invention discloses a device and a method for measuring effective influence radius of a gas extraction drill hole. According to the invention, only one core drill hole is constructed in the original coal seam, then the coal core sample is collected and measured in the laboratory, and a series of gas extraction drill holes and pressure observation drill holes do not need to be constructed in the coal seam, so that the engineering quantity is greatly reduced, and the test success rate is higher than that of the traditional measuring method; the coal quality, the pores and the cracks of the coal core sample are relatively uniform, so that errors caused by geological occurrence change of gas can be avoided, the coal core sample is sealed in the coal core clamp holder, the problem of long exposure time does not exist, and the determination accuracy is high; the method can realize tracking monitoring in the middle process of not reaching the extraction time, further guarantee the accuracy of determination, and the determination result can provide theoretical basis and data support for reasonable arrangement of the coal seam gas extraction drill hole.
Description
Technical Field
The invention relates to a measuring device and a measuring method, in particular to a device and a measuring method suitable for measuring effective influence radius of a gas extraction drill hole, and belongs to the technical field of prevention and control and efficient development of coal mine gas disasters.
Background
The method is a main means for gas disaster control and gas extraction utilization of China coal mine enterprises at present by arranging gas extraction drill holes in a coal seam to extract and discharge gas. One of the important tasks in designing coal seam gas extraction boreholes is to determine the spacing between extraction boreholes, i.e., the distance between two adjacent boreholes. If the spacing between the gas extraction drill holes is too small, the drilling engineering quantity is large, the cost is high, and the economic benefit is low; if the distance between the gas extraction drill holes is too large, the gas extraction effect is poor, extraction blank zones are easily left in the coal seam, and further, gas overrun accidents are easily caused when the area is excavated or stoped in the later period. Therefore, before designing the borehole, the reasonable effective influence radius of the gas extraction borehole needs to be tested and determined in advance.
The pressure drop method is characterized in that firstly, a drainage borehole is constructed in a coal seam, then a plurality of pressure observation holes with unequal intervals are arranged on two sides of the borehole (most of design methods are 3 boreholes on two sides), if the pressure of the observation holes is reduced to an expected value (usually about 50% of the original coal seam gas pressure), the distance from the borehole to the drainage hole is considered to be the effective influence radius of gas drainage, ① has the defects that the distance between the pressure observation borehole arranged on two sides of the drainage hole and the gas drainage borehole is small (within 3 m), and therefore cross holes are easy to occur, and further the pressure measurement fails, ② is a high-height rock material, the internal pores of the coal seam are rich and uneven, and besides many small structural cracks exist in the coal seam, so that the measured pressure is inconsistent, the reliability of the coal seam is poor, the coal seam is subjected to comparative analysis, the effective influence radius of the coal seam is at least tested, and the construction success rate of the actual field construction is at least low because ③ gas drainage hole pressure is difficult to be tested, and the construction success rate is at least high.
The residual gas content measuring method has the advantages that ① is difficult to determine whether a sampling drill hole with low gas content is influenced by extraction or is originally low due to the fact that the residual gas content is heterogeneous and the gas content distribution is not uniform, ② coal sample exposure time is too long in the sampling process, errors are large, and ③ is compared with the pressure drop method, the residual gas content measuring method cannot observe the content change situation every day, only can sample once after the extraction time is reached, and cannot track and observe in the middle process of not reaching the extraction time.
In view of the disadvantages of the pressure drop method and the residual gas content measurement method, some researchers have proposed numerical simulation methods to eliminate the above-mentioned influencing factors, but the field test of a large number of parameters as model input is also required, and the method is not an economically feasible solution.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a device and a method for measuring the effective influence radius of a gas extraction borehole, which can be used for efficiently and accurately measuring the effective influence radius of the gas extraction borehole, and further provide theoretical basis and data support for reasonable arrangement of the coal seam gas extraction borehole.
In order to achieve the purpose, the device for measuring the effective influence radius of the gas extraction drill hole comprises a coal core holder, a gas injection part, a gas simulation extraction part and a pressure test part;
the coal core clamp comprises a cylinder, a plug and an annular sealing gasket assembly; the barrel is of a barrel-shaped structure, a pressure stabilizing end and a negative pressure end are arranged at two ends of the barrel-shaped structure along the axial direction of the barrel-shaped structure, a plurality of pressure measuring ports which are uniformly distributed are arranged on the outer surface of the barrel-shaped structure along the axial direction of the barrel-shaped structure, and the pressure measuring ports penetrate through the barrel wall of the barrel-shaped structure along the radial direction of the barrel-shaped structure; the two plugs are respectively and fixedly arranged on the pressure stabilizing end and the negative pressure end in a sealing way, and gas inlet and outlet channels penetrating through the plugs are arranged on the plugs along the axial direction of the plugs; the number of the annular sealing gasket assemblies corresponding to the plugs is two, and the annular sealing gasket assemblies are arranged at the end parts of the plugs facing the inner cavity of the barrel;
the gas injection parts are arranged into two sets, the two sets of gas injection parts are respectively arranged corresponding to the pressure stabilizing end and the negative pressure end, the gas injection parts comprise gas pressure gas cylinders, the output ports of the gas pressure gas cylinders corresponding to the pressure stabilizing ends are connected with the gas inlet and outlet channels of the plugs positioned on the pressure stabilizing ends through pressure stabilizing valves, and the output ports of the gas pressure gas cylinders corresponding to the negative pressure ends are connected with the gas inlet and outlet channels of the plugs positioned on the negative pressure ends through three-way valves;
the gas simulation extraction part comprises a vacuum pump, and the vacuum pump is connected with the other passage of the three-way valve in an installing manner;
the pressure testing part comprises a pressure sensor and a monitoring computer; the pressure sensors are arranged corresponding to the pressure measuring ports of the barrel, the pressure input ends of the pressure sensors are connected with the pressure measuring ports of the barrel through pressure measuring valves, and the pressure sensors are electrically connected with the monitoring computer respectively.
As a further improvement scheme of the invention, the gas injection part also comprises a constant pressure delivery pump, the input end and the output end of the constant pressure delivery pump corresponding to the pressure stabilizing end are respectively connected with the gas pressure cylinder and the pressure stabilizing valve corresponding to the pressure stabilizing end, and the input end and the output end of the constant pressure delivery pump corresponding to the negative pressure end are respectively connected with the gas pressure cylinder and the three-way valve corresponding to the negative pressure end.
As a further improvement scheme of the invention, the pressure stabilizing valve, the three-way valve and the pressure measuring valve are all electromagnetic control valves, and the pressure stabilizing valve, the three-way valve and the pressure measuring valve are respectively and electrically connected with a monitoring computer.
As an embodiment of the annular gasket assembly of the present invention, the annular gasket assembly is a combined gasket structure, and includes a rubber gasket, a copper gasket, and a teflon gasket, which are sequentially disposed from inside to outside.
As a further improvement scheme of the invention, the polytetrafluoroethylene sealing ring is of a conical structure with a large outer part and a small inner part, and the inner side end of the plug is arranged into a conical surface structure matched with the conical structure of the polytetrafluoroethylene sealing ring.
As a further improvement of the invention, the number of the pressure measuring ports is not less than 5.
A method for measuring effective influence radius of a gas extraction drill hole comprises the following steps:
a. constructing a gas pressure measuring borehole in a region of which the gas extraction influence radius is to be measured, measuring and recording the gas pressure of an original coal seam;
b. constructing a core drilling hole in the coal seam or the cross-cut layer of the area and taking out a coal core sample, putting the coal core sample into a coal core clamp of a device for measuring the effective influence radius of the gas extraction drilling hole, stably positioning the coal core sample through an annular sealing pad assembly and a plug, and transporting a cylinder body packaged with the coal core sample to a ground laboratory after the gas inlet and outlet channel for plugging the plug seals the coal core sample in a closed manner;
c. the method comprises the following steps of installing and connecting a cylinder body packaged with a coal core sample with a gas injection part, a gas simulation extraction part and a pressure testing part, then adjusting the constant pressure output pressure of a constant pressure delivery pump to be the original coal seam gas pressure, opening a gas pressure gas cylinder, then sequentially opening the constant pressure delivery pump and a pressure stabilizing valve corresponding to a pressure stabilizing end, controlling a three-way valve to enable the constant pressure delivery pump corresponding to a negative pressure end to be communicated with a gas inlet and outlet channel of a plug corresponding to the negative pressure end, and simultaneously injecting gas into the coal core sample from two ends of the cylinder body;
d. opening all pressure measuring valves, counting and recording pressure values fed back by each pressure sensor by a monitoring computer, keeping the opening state of a pressure stabilizing valve when the values of the pressure sensors reach the original gas pressure of the coal bed, setting a three-way valve after the pressure of a vacuum pump is released so that the vacuum pump corresponding to the negative pressure end is communicated with a gas inlet and outlet channel of a plug corresponding to the negative pressure end, and starting the vacuum pump for simulated extraction;
e. the control monitoring computer intermittently counts and records pressure values fed back by each pressure sensor until preset extraction days are reached;
f. and fitting the pressure numerical values of the pressure sensors by using an exponential function according to a built-in program by using the monitoring computer, then substituting the pressure numerical values required by the extraction influence radius into the fitting to obtain a function formula, and solving the gas extraction influence radius of the original coal seam.
As a further improvement of the invention, at least two gas pressure measuring drill holes are constructed in the step a, the original coal seam gas pressure is respectively measured on the gas pressure measuring drill holes, and the constant pressure output pressure of the constant pressure delivery pump is adjusted to be the maximum value in the original coal seam gas pressure values in the step c.
As a further improvement of the invention, the length of the coal core sample in the step b is not less than 3m, and the end face of the coal core sample is polished to be flat.
As a further improvement scheme of the invention, the coal core sample in the step b is a whole-block integrated structure or a structure formed by a plurality of sample sections with different lengths, and the end surfaces of the coal core sample or the sample sections are polished to be flat.
Compared with the prior art, the device and the method for measuring the effective influence radius of the gas extraction drill hole only need to construct a core drill hole in an original coal seam and then collect a coal core sample, and measure the sample in a laboratory, but do not need to construct a series of gas extraction drill holes and pressure observation drill holes in the coal seam, so that the engineering quantity is greatly reduced, and the test success rate is higher than that of the traditional measuring method; in addition, the method only needs one coal core with smaller size, the coal quality and the pores and the cracks in the coal core are relatively uniform, the error caused by the geological occurrence change of the gas can be avoided, the problem of long exposure time does not exist because the coal core sample is sealed in the coal core clamp holder, and the determination accuracy is higher; the method adopts a continuous monitoring mode, can realize tracking monitoring in the middle process of not reaching the extraction time, further can ensure the accuracy of measurement, and the measurement result can provide theoretical basis and data support for reasonable arrangement of the coal bed gas extraction drill hole.
Drawings
FIG. 1 is a schematic structural diagram of a device for determining the effective influence radius of a gas extraction borehole according to the invention;
FIG. 2 is a graph of an exponential function fit according to an embodiment of the present invention.
In the figure: 1. the device comprises a coal core sample, 2, a cylinder, 3, a rubber gasket, 4, a copper gasket, 5, a polytetrafluoroethylene sealing ring, 6, a plug, 7, a gas pressure cylinder, 8, a constant pressure delivery pump, 9, a pressure stabilizing valve, 10, a three-way valve, 11, a pressure sensor, 12, a monitoring computer, 13, a pressure measuring valve, 14, a vacuum pump, 15, a pressure stabilizing end, 16 and a negative pressure end.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in figure 1, the device for measuring the effective influence radius of the gas extraction drill hole comprises a coal core holder, a gas injection part, a gas simulation extraction part and a pressure test part.
The coal core clamp comprises a cylinder body 2, a plug 6 and an annular sealing gasket assembly; the barrel 2 is a barrel-shaped structure, the two ends of the barrel-shaped structure along the axial direction are a voltage-stabilizing end 15 and a negative-pressure end 16, the outer surface of the barrel-shaped structure is provided with a plurality of pressure measuring ports which are uniformly distributed along the axial direction, the pressure measuring ports penetrate through the barrel wall of the barrel-shaped structure along the radial direction of the barrel-shaped structure, and the number of the pressure measuring ports is not less than 5 in order to ensure the accuracy of pressure measurement; the two plugs 6 are arranged, the two plugs 6 are respectively and fixedly arranged on the pressure stabilizing end 15 and the negative pressure end 16 in a sealing way, and the plugs 6 are provided with gas inlet and outlet channels penetrating through the plugs 6 along the axial direction; the annular sealing gasket assemblies are arranged in two sets corresponding to the number of the plugs 6, the annular sealing gasket assemblies are arranged at the end parts, facing the inner cavity of the barrel body 2, of the plugs 6, the annular sealing gasket assemblies can adopt rubber sealing gasket structures and can also adopt combined sealing gasket structures such as framework sealing structures, and the like.
The gas injection parts are arranged in two sets, the two sets of gas injection parts are respectively arranged corresponding to the pressure stabilizing end 15 and the negative pressure end 16, the gas injection parts comprise gas pressure gas cylinders 7, the output ports of the gas pressure gas cylinders 7 corresponding to the pressure stabilizing end 15 are connected with the gas inlet and outlet channels of the plugs 6 positioned on the pressure stabilizing end 15 through pressure stabilizing valves 9, and the output ports of the gas pressure gas cylinders 7 corresponding to the negative pressure end 16 are connected with the gas inlet and outlet channels of the plugs 6 positioned on the negative pressure end 16 through three-way valves 10.
The gas simulation extraction part comprises a vacuum pump 14, and the vacuum pump 14 is connected with the other passage of the three-way valve 10 in an installing manner.
The pressure testing part comprises a pressure sensor 11 and a monitoring computer 12; the pressure sensors 11 are arranged corresponding to the number of pressure measuring ports of the cylinder body 2, the pressure input end of each pressure sensor 11 is connected with the pressure measuring port of the cylinder body 2 through a pressure measuring valve 13, and the pressure sensors 11 are respectively and electrically connected with the monitoring computer 12.
In the measuring process, in order to facilitate the constant pressure control of the gas input pressure of the gas injection part, as a further improvement scheme of the invention, the gas injection part also comprises a constant pressure delivery pump 8, the input end and the output end of the constant pressure delivery pump 8 corresponding to the pressure stabilizing end 15 are respectively connected with the gas pressure gas cylinder 7 and the pressure stabilizing valve 9 corresponding to the pressure stabilizing end 15, and the input end and the output end of the constant pressure delivery pump 8 corresponding to the negative pressure end 16 are respectively connected with the gas pressure gas cylinder 7 and the three-way valve 10 corresponding to the negative pressure end 16.
The method for measuring the effective influence radius of the gas extraction drill hole is described by taking gas drainage of the gas extraction drill hole arranged in a certain coal seam as an example:
firstly, constructing three gas pressure measuring drill holes in a region of which the gas extraction influence radius is to be measured, and measuring to obtain the original coal seam gas pressure of 1.8MPa, 1.0MPa and 1.6MPa respectively;
then, constructing a core drill hole in the coal seam or a cross layer of the area, taking a coal core sample 1 with the length of 3.6m and the outer diameter size matched with the inner diameter size of the cylinder 2, dividing the coal core sample 1 into two sections, wherein each section is 1.8m long, then polishing and flattening all four end faces by 1000-mesh water sand paper, ensuring that the sum of the lengths of the two sections of the coal core samples 1 is matched with the length size of the inner cavity of the cylinder 2, and then sequentially placing the two sections of the coal core samples 1 into the cylinder 2; sequentially filling a rubber gasket 3 and a copper gasket 4 into a pressure stabilizing end 15 and a negative pressure end 16, then sleeving a tapered polytetrafluoroethylene sealing ring 5 on a plug 6, then respectively screwing the plugs 6 tightly at two ends of a barrel 2, firmly positioning a coal core sample 1 in the barrel 2 under the clamping action of the plug 6 and an annular sealing gasket assembly, plugging a gas inlet and outlet channel of the plug 6 to finish the sealed storage of the coal core sample 1, and finally transporting the barrel 2 packaged with the coal core sample 1 to a ground laboratory;
the method comprises the following steps of installing and connecting a cylinder 2 packaged with a coal core sample 1 with a gas injection part, a gas simulation extraction part and a pressure test part, setting the distance between pressure sensors 11 to be 40cm, setting the distance between the pressure sensor 11 located on the outermost side of the cylinder 2 and a pressure stabilizing end 15 and a negative pressure end 16 to be 10cm respectively, adjusting the constant pressure output pressure of a constant pressure delivery pump 8 to be 1.8MPa (maximum coal bed gas pressure), opening a gas pressure cylinder 7, sequentially starting the constant pressure delivery pump 8 and a pressure stabilizing valve 9 corresponding to the pressure stabilizing end 15, controlling a three-way valve 10 to enable the constant pressure delivery pump 8 corresponding to the negative pressure end 16 to be communicated with a gas inlet and outlet channel of a plug 6 corresponding to the negative pressure end 16, and simultaneously injecting gas into the coal core sample 1 from two ends of the cylinder 2;
then all pressure measuring valves 13 are opened, and the monitoring computer 12 performs intermittent statistics and records on pressure values fed back by all the pressure sensors 11;
after 7 days of saturation, the numerical values of all the pressure sensors 11 are increased from OMPa to 1.8MPa, then the opening state of the pressure stabilizing valve 9 is maintained, the pumping pressure of the vacuum pump 14 is set to-13 KPa, the three-way valve 10 is rotationally connected to the vacuum pump 14, and then the vacuum pump 14 is started for simulated pumping;
the control monitoring computer 12 counts and records the pressure value fed back by each pressure sensor 11 every 24 hours, the pressure value of each pressure sensor 11 after reaching the preset extraction days (30 days) is shown in the following table,
| serial number | Distance d (cm) | Pressure p (MPa) |
| 1 | 0 | -0.013 |
| 2 | 10 | 0.18 |
| 3 | 50 | 0.55 |
| 4 | 90 | 0.9 |
| 5 | 130 | 1.18 |
| 6 | 170 | 1.41 |
| 7 | 210 | 1.56 |
| 8 | 250 | 1.68 |
| 9 | 290 | 1.75 |
| 10 | 300 | 1.8 |
The monitoring computer 12 fits the pressure values of the individual pressure sensors 11 according to a built-in program using an exponential function, as shown in fig. 2, where the formula for the exponential function is p-1.8-0.184 ed/110P is the gas pressure, dIs the distance from the voltage stabilization end; the measurement considers that the gas pressure is reduced to 50 percent (0.9MPa) of the original gas pressure in 30 days, and the gas pressure is substituted into the fitting to obtain a function formula, so that the gas extraction influence radius of the corresponding coal seam is 0.81 m.
In order to realize the automatic operation of the measuring process, as a further improvement scheme of the invention, the pressure stabilizing valve 9, the three-way valve 10 and the pressure measuring valve 13 are all electromagnetic control valves, the pressure stabilizing valve 9, the three-way valve 10 and the pressure measuring valve 13 are respectively and electrically connected with the monitoring computer 12, and the automatic opening and closing of each valve can be realized by controlling the monitoring computer 12.
In order to realize a better sealing and storing effect of the coal core sample 1, as a further improvement scheme of the invention, the polytetrafluoroethylene sealing ring 5 is of a conical structure with a large outer part and a small inner part, and the inner side end of the plug 6 is provided with a conical surface structure matched with the conical structure of the polytetrafluoroethylene sealing ring 5.
Claims (10)
1. A device for measuring the effective influence radius of a gas extraction drill hole is characterized by comprising a coal core holder, a gas injection part, a gas simulation extraction part and a pressure test part;
the coal core clamp comprises a cylinder body (2), a plug (6) and an annular sealing gasket assembly; the barrel (2) is of a barrel-shaped structure, a pressure stabilizing end (15) and a negative pressure end (16) are arranged at two ends of the barrel-shaped structure along the axial direction of the barrel-shaped structure, a plurality of pressure measuring ports are uniformly distributed on the outer surface of the barrel-shaped structure along the axial direction of the barrel-shaped structure, and the pressure measuring ports penetrate through the barrel wall of the barrel-shaped structure along the radial direction of the barrel-shaped structure; the two plugs (6) are respectively arranged on the pressure stabilizing end (15) and the negative pressure end (16) in a sealing and fixed mode, and a gas inlet and outlet channel penetrating through the plugs (6) is formed in the plugs (6) along the axial direction of the plugs (6); the number of the annular sealing pad assemblies corresponding to the number of the plugs (6) is two, and the annular sealing pad assemblies are arranged at the end parts, facing the inner cavity of the barrel body (2), of the plugs (6);
the gas injection parts are arranged into two sets, the two sets of gas injection parts are respectively arranged corresponding to the pressure stabilizing end (15) and the negative pressure end (16), the gas injection parts comprise gas pressure gas cylinders (7), the output ports of the gas pressure gas cylinders (7) corresponding to the pressure stabilizing ends (15) are connected with a gas inlet and outlet channel of a plug (6) positioned on the pressure stabilizing end (15) through pressure stabilizing valves (9), and the output ports of the gas pressure gas cylinders (7) corresponding to the negative pressure end (16) are connected with the gas inlet and outlet channel of the plug (6) positioned on the negative pressure end (16) through three-way valves (10);
the gas simulated extraction part comprises a vacuum pump (14), and the vacuum pump (14) is connected with the other passage of the three-way valve (10) in an installing manner;
the pressure testing part comprises a pressure sensor (11) and a monitoring computer (12); the pressure sensors (11) are arranged corresponding to the pressure measuring ports of the barrel body (2), the pressure input ends of the pressure sensors (11) are connected with the pressure measuring ports of the barrel body (2) through pressure measuring valves (13), and the pressure sensors (11) are respectively electrically connected with the monitoring computer (12).
2. The device for measuring the effective influence radius of the gas extraction drill hole according to claim 1, wherein the gas injection part further comprises a constant pressure delivery pump (8), the input end and the output end of the constant pressure delivery pump (8) corresponding to the pressure stabilizing end (15) are respectively connected with the gas pressure gas cylinder (7) and the pressure stabilizing valve (9) corresponding to the pressure stabilizing end (15), and the input end and the output end of the constant pressure delivery pump (8) corresponding to the negative pressure end (16) are respectively connected with the gas pressure gas cylinder (7) and the three-way valve (10) corresponding to the negative pressure end (16).
3. The device for determining the effective influence radius of the gas extraction borehole according to claim 1 or 2, wherein the pressure stabilizing valve (9), the three-way valve (10) and the pressure measuring valve (13) are all electromagnetic control valves, and the pressure stabilizing valve (9), the three-way valve (10) and the pressure measuring valve (13) are respectively and electrically connected with the monitoring computer (12).
4. The device for measuring the effective influence radius of the gas extraction drill hole according to claim 1 or 2, wherein the annular sealing gasket assembly is of a combined sealing gasket structure and comprises a rubber gasket (3), a copper gasket (4) and a polytetrafluoroethylene sealing ring (5) which are sequentially arranged from inside to outside.
5. The device for measuring the effective influence radius of the gas extraction drill hole according to claim 4, wherein the polytetrafluoroethylene sealing ring (5) is of a conical structure with a large outer part and a small inner part, and the inner end of the plug (6) is provided with a conical surface structure matched with the conical structure of the polytetrafluoroethylene sealing ring (5).
6. The device for measuring the effective influence radius of the gas extraction borehole according to claim 1 or 2, wherein the number of pressure measurement ports is not less than 5.
7. A method for determining an effective influence radius of a gas extraction borehole using the apparatus for determining an effective influence radius of a gas extraction borehole according to claim 2, comprising the steps of:
a. constructing a gas pressure measuring borehole in a region of which the gas extraction influence radius is to be measured, measuring and recording the gas pressure of an original coal seam;
b. constructing a core drilling hole in the coal seam or the cross-cut layer of the area and taking out a coal core sample (1), putting the coal core sample (1) into a coal core clamp of a device for measuring the effective influence radius of the gas extraction drilling hole, stably positioning the coal core sample through an annular sealing pad assembly and a plug (6), sealing and storing the coal core sample (1) through a gas inlet and outlet channel of the plug (6), and transporting a cylinder (2) packaged with the coal core sample (1) to a ground laboratory;
c. the method comprises the steps that a cylinder (2) packaged with a coal core sample (1) is installed and connected with a gas injection part, a gas simulation extraction part and a pressure testing part, then the constant pressure output pressure of a constant pressure delivery pump (8) is adjusted to be the original coal seam gas pressure, a gas pressure gas cylinder (7) is opened, then the constant pressure delivery pump (8) and a pressure stabilizing valve (9) corresponding to a pressure stabilizing end (15) are sequentially opened, a three-way valve (10) is controlled to enable the constant pressure delivery pump (8) corresponding to a negative pressure end (16) to be communicated with a gas inlet and outlet channel of a plug (6) corresponding to the negative pressure end (16), and gas is simultaneously injected into the coal core sample (1) from two ends of the cylinder (2);
d. opening all pressure measuring valves (13), counting and recording pressure values fed back by each pressure sensor (11) by a monitoring computer (12), keeping the opening state of a pressure stabilizing valve (9) when the values of the pressure sensors reach the original gas pressure of the coal bed, setting a three-way valve (10) after the pressure of a vacuum pump (14) is released, communicating the vacuum pump (14) corresponding to a negative pressure end (16) with a gas inlet and outlet channel of a plug (6) corresponding to the negative pressure end (16), and starting the vacuum pump (14) to perform simulated extraction;
e. the control monitoring computer (12) intermittently counts and records pressure values fed back by the pressure sensors (11) until preset extraction days are reached;
f. and the monitoring computer (12) fits the pressure numerical values of the pressure sensors (11) by using an exponential function according to a built-in program, then brings the pressure numerical values required by the extraction influence radius into the fit to obtain a function formula, and obtains the gas extraction influence radius of the original coal seam.
8. The method for measuring the effective influence radius of the gas extraction borehole according to claim 7, wherein at least two gas pressure measurement boreholes are constructed in the step a, original coal seam gas pressures are respectively measured on the gas pressure measurement boreholes, and the constant pressure output pressure of the constant pressure delivery pump (8) is adjusted to be the maximum value of the original coal seam gas pressure values in the step c.
9. The method for measuring the effective influence radius of the gas extraction borehole according to claim 7, wherein the length of the coal core sample (1) in the step b is not less than 3m, and the end face of the coal core sample (1) is polished flat.
10. The method for determining the effective influence radius of the gas extraction borehole according to claim 7, wherein in the step b, the coal core sample (1) is of a monolithic structure or a structure formed by a plurality of sample sections with different lengths, and the end faces of the coal core sample (1) or the sample sections are polished to be flat.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910333945.8A CN110219699B (en) | 2019-04-24 | 2019-04-24 | Device and method for measuring effective influence radius of gas extraction drill hole |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910333945.8A CN110219699B (en) | 2019-04-24 | 2019-04-24 | Device and method for measuring effective influence radius of gas extraction drill hole |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110219699A CN110219699A (en) | 2019-09-10 |
| CN110219699B true CN110219699B (en) | 2020-04-03 |
Family
ID=67819976
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910333945.8A Active CN110219699B (en) | 2019-04-24 | 2019-04-24 | Device and method for measuring effective influence radius of gas extraction drill hole |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110219699B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115387775B (en) * | 2022-08-01 | 2023-07-18 | 太原理工大学 | Method for collaborative extraction and outburst elimination of gas extracted from adjacent coal seam based on tree-shaped long drilling holes |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102230375B (en) * | 2011-06-10 | 2014-05-14 | 中国矿业大学 | Method for monitoring coal bed gas parameter in real time |
| CN103114870B (en) * | 2013-01-23 | 2015-04-29 | 重庆大学 | Multi-field coupling coal bed methane extraction physical simulation testing system |
| CN104295289B (en) * | 2014-08-14 | 2017-05-10 | 神华集团有限责任公司 | Gas extraction radius determining method for strike long drilled hole |
| CN104389559B (en) * | 2014-09-30 | 2017-04-26 | 河南理工大学 | Method and device for preventing and controlling gas transfinite in thick-coal-seam mining process |
| CN205714091U (en) * | 2016-06-15 | 2016-11-23 | 华北科技学院 | The device in analog band pressure grouting closure boring coal petrography crack |
| CN106761572A (en) * | 2016-11-22 | 2017-05-31 | 西安科技大学 | A kind of Multi-functional analog boring test platform and its application method |
| CN107542486B (en) * | 2017-09-30 | 2018-07-03 | 西安科技大学 | Drilling gas extraction laboratory simulation method and sealing material method for testing tightness |
-
2019
- 2019-04-24 CN CN201910333945.8A patent/CN110219699B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110219699A (en) | 2019-09-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109269901B (en) | Pressure-sensitive multi-scale horizontal seam comprehensive regulation and control simulation experiment device and method | |
| CN109612907B (en) | Testing device and method for permeability test of fractured coal rock mass | |
| CN112031727B (en) | Physical simulation device and method for fracturing horizontal well multi-medium throughput | |
| CN111337411B (en) | Method and device for testing radial permeability of full-diameter shale | |
| CN106437694B (en) | Coal powder discharge change monitoring device for simulating coal seam fracturing action and experimental method thereof | |
| CN109975140B (en) | Supercritical carbon dioxide pulse fracturing and permeability testing integrated experimental device and method | |
| CN110501272B (en) | Method for simultaneously testing porosity and permeability of porous rock under triaxial stress and pore pressure conditions | |
| CN204422525U (en) | High-temperature high pressure water mudding performance test evaluating apparatus | |
| CN109374498B (en) | Single-crack rock mass seepage stress coupling system and method | |
| CN103592213A (en) | Diversion acidizing experimental apparatus suitable for multiple permeability max-min ratios and evaluation method | |
| CN105974084A (en) | In-coal-seam gas extraction experiment simulation device | |
| CN110308052B (en) | Hollow rock sample radial seepage test device and test method based on acoustic emission technology | |
| CN110219699B (en) | Device and method for measuring effective influence radius of gas extraction drill hole | |
| WO2019227881A1 (en) | Apparatus and method for formation pressure test physical simulation and scaling | |
| CN110056335B (en) | Triaxial multi-crack hydraulic fracturing experimental device and experimental method | |
| CN105004509A (en) | Water and mud outburst test device for tectonic fracture filling structure | |
| CN109211757B (en) | Rock penetration test device and test method thereof | |
| CN111551475B (en) | Portable device and method for rapidly testing permeability of coal seam in situ through layer drilling | |
| CN110261569A (en) | Experimental system for simulating and method based on pipe network system draining coal seam gas effect | |
| CN104931403B (en) | Anisotropic rock degree of injury test device and its test method | |
| CN110441221B (en) | Full-diameter shale core annular sealed cabin clamping device and measuring process | |
| CN103513011A (en) | Automatic calibration device for gas in transformer oil | |
| CN110847889A (en) | Hydraulic fracturing test system and test method | |
| CN202255743U (en) | Coal mine underground gas pressure measuring system | |
| CN108169098B (en) | Reasonable drainage and production speed simulation device for single-phase flow stage of coalbed methane vertical well |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |