CN103089295B - Coal bed gas extraction test method in multiple seam unitized production process - Google Patents
Coal bed gas extraction test method in multiple seam unitized production process Download PDFInfo
- Publication number
- CN103089295B CN103089295B CN201310025114.7A CN201310025114A CN103089295B CN 103089295 B CN103089295 B CN 103089295B CN 201310025114 A CN201310025114 A CN 201310025114A CN 103089295 B CN103089295 B CN 103089295B
- Authority
- CN
- China
- Prior art keywords
- gas
- extraction
- coal
- test
- seam
- 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
Abstract
The invention discloses coal bed gas extraction test method in a kind of multiple seam unitized production process, comprise step as follows: 1, early-stage preparations; 2, gas adsorption; 3, gas pumping; 4, single test is terminated; 5, change simulation adopt dark or model face propulsion speed wherein one of test parameters, and keep other test parameters constant, repeat above step 2-4.The present invention can in the coal bed gas extraction of experiment lab simulation field working conditions, reproduce the situation of change of coal seam parameter in actual condition, thus the change of research stress field, crack field, seepage field, thermal field, the temporal-spatial evolution that analysis coal seam coal gas dynamics is coupled with coal and rock crack and the regularity of distribution.
Description
Technical field
The present invention relates to a kind of pilot system and the method for simulating coal-bed gas exploitation process under multi-scenarios method mechanism of action.
Background technology
Coal bed gas is a kind of energy of potential cleaning.Under the situation of current energy source anxiety, accelerate the exploitation of coal bed gas, to improving China's energy resource structure, making full use of and reducing environment pollution etc. and have important practical significance the energy.From the angle of mineral resources, coal bed gas take methane as Main Ingredients and Appearance (content > 85%), formed in incoalation process, preserve coal bed gas and close among rock stratum, can exploitation technology by its extraction the Unconventional forage be used from coal seam.China's coal bed gas resource enriches, and according to coal bed gas resource evaluation, China's buried depth 2000 meters, with shallow coal bed gas geological resources about 36.81 tcm, occupies third place in the world, is mainly distributed in North China and the Northwest.Wherein, North China, the Northwest, southern area and the Northeast compose that the coal bed gas geological resources deposited accounts for national coal bed gas geological resource total amount respectively 56.3%, 28.1%, 14.3%, 1.3%.
Modal cbm development mode mainly contains two kinds, that is: down-hole coal bed gas extraction and mining with surface drill well.Down-hole extraction coal bed gas is drilling from underground coal mine digging tunnel, is extracted the coal bed gas in coal seam on ground by coal seam air pump.The methane output of this development scheme is less, methane concentration not high (20% ~ 50%), and is easily subject to the impact of colliery digging production, so it is mainly with for the purpose of Safety of Coal Mine Production, the utilization rate of coal bed gas is lower.From the 1950's, coal bed gas extraction is just promoted as the important measures of administering coal mine gas disaster at high methane and projecting mine by China.Since half a century, mine quantity and the gas suction amount of China's enforcement coal bed gas extraction grow steadily year by year.But the main feature in China coal seam is that gas permeability of coal seam is low, gas bearing capacity is high, Coal Outburst dangerous serious, coal seam group mining, complicated geological, the condition of coal seam occurrence of China determines the coal bed gas extraction of China should based on release extraction.Mining with surface drill well coal bed gas enters solid coal seam from ground drilling, by the coal bed gas in drainage and step-down desorb coal output layer, then by Wellbore Flow to ground.The gas production of this mining type is large, the aerogenesis time is long, methane content high (being greater than 90%), utilize so large-scale commercialization can be supported, but in order to ensure the workability of coal bed gas, and obtain certain economic benefit, this development scheme has higher requirement to Coal bed gas project, coal geology structure, air content, permeability, geographical environment etc.
At present, China's overall coal bed gas gas drainage results is not good, is embodied in coal bed gas Drained rate low.The low reason of China's coal-mine coal bed gas Drained rate is caused to have 2 aspects: be odjective cause on the one hand, the coal seam that the high coal bed gas of China more than 95% and projecting mine are exploited belongs to low air permeability coal seam, and Permeability Coefficent in Coal Seam only has 0.004 ~ 0.04m
2/ (MPa
2d), coal bed gas extraction (particularly taking out in advance) difficulty is very large; Be subjective reason on the other hand, main manifestations is that the extraction time is short, borehole engineering quantity not sufficient, sealing quality are poor, drainage system does not mate and manage not in place.Therefore study and how effective extraction is carried out to coal bed gas there is extremely important engineering significance.
On the other hand, theoretical according to ore deposit pressure, after seam mining, its roof strata generation inbreak is moved, after overlying rock sinks to stablizing, overlying rock mining induced fissure zoning can be divided into " perpendicular three band " and " Heng Sanqu ", and namely minery is vertically divided into caving zone, fissure zone and warp damage from lower to upper; Rib is divided into support influence area, absciss layer district and compacting zone again along advance of the face direction at work plane air way and region, machine lane.Along with work plane is constantly pushed ahead, alternately move forward along " Heng Sanqu " on work direction of propulsion thereupon.In the process of coal bed gas extraction, the migration of gas in coal rock layer will be subject to " perpendicular three bands " and the impact of the new gap region distribution produced in " Heng Sanqu ", and reasonably utilize the new crack produced in " perpendicular three bands " and " Heng Sanqu " to have important impact to raising extraction efficiency.
Experimental rig or the method for coal bed gas extraction simulation is not also carried out at present in laboratory, the state that laboratory can be simulated is mostly in false three axle Coal Under layer permeability along with stress, gas pressure, variations in temperature and the relation changed, and proposes the method for various raising coal seam permeability on this basis.Although the test of these seepage simulations describes the influence that various influence factor flows to coal seam coal bed gas to a certain extent, but in view of the complexity of extraction work and system thereof, these emulation modes differ comparatively far away with on-site actual situations, can not illustrate that the coal bed gas extraction under physical condition is subject to the effect of each factor.
Therefore those skilled in the art be devoted to exploitation a kind of can in the experimental rig of laboratory physical analogy coal bed gas extraction and method.
Summary of the invention
Because the above-mentioned defect of prior art, technical problem to be solved by this invention be to provide a kind of can in the experimental rig of laboratory physical analogy coal bed gas extraction and method.
For achieving the above object, the invention provides a kind of multi-scenarios method coal-bed gas exploitation physical simulation experiment system, comprise test piece box; Described test piece box top is provided with at least one Z-direction depression bar and Z-direction pressing plate;
The right boxboard of described test piece box is provided with at least one Y-direction depression bar and Y-direction pressing plate;
The rearing-box plate of described test piece box is provided with at least one X to depression bar and X to pressing plate;
Described Z-direction pressing plate, Y-direction pressing plate and X are all positioned at described test piece box to pressing plate;
The front boxboard of described test piece box is provided with stair-stepping aspis; Outstanding cover has been bolted to connection in described aspis; The first sealing ring is provided with between the cascaded surface of described outstanding cover and described front boxboard;
The bottom of described test piece box is provided with air permeable steel plate and air flue; Described air permeable steel plate covers on described air flue; The import of described air flue is provided with interior plug;
The left boxboard space outside of described test piece box is fixedly connected with the first backing plate; Described left boxboard is provided with interface between the interval of each first backing plate; Sensor connector is provided with in described interface;
The endoporus of described outstanding cover is pre-large post-small shoulder hole, is provided with the outer tube holder that shape is corresponding with shoulder hole in this shoulder hole; The second sealing ring is provided with between the cascaded surface of described outstanding cover and described outer tube holder; Be threaded in the endoporus of described outer tube holder outer tube; Described outer tube extends in described test piece box;
The front end face of described outstanding cover has been bolted mounting flange; The 3rd sealing ring is provided with between described outer tube holder and described mounting flange; The front end of described mounting flange is provided with flange boss; The cylindrical of described flange boss is provided with screw thread;
The back-end closure of described outer tube, front opening; Described outer tube is provided with the extraction outskirt that position is corresponding with each described Z-direction depression bar; Described extraction outskirt is provided with some extraction exit orifice;
Interior pipe is provided with in described outer tube and mounting flange; Described interior pipe comprises the first adapter and the 3rd adapter, and optionally one or more second adapter; Described first adapter, the second adapter and the 3rd adapter can be threaded front and back successively, and connecting thread has interchangeability; What described first adapter, the second adapter and the 3rd were taken over is provided with sealing ring in conjunction with end; The external diameter of described first adapter and the second adapter is less than the internal diameter of described outer tube;
The described first corresponding described flange boss place of adapter is provided with defining flange; Described first adapter is provided with screw thread at the front end cylindrical of described defining flange; The first joint is combined with in the front end endoporus of described first adapter;
The external screw thread of described defining flange and flange boss is combined with nut;
Described first adapter and the second adapter are provided with through hole vertically; Described 3rd adapter is provided with the blind hole of front opening back-end closure vertically;
Described 3rd adapter is provided with extraction inner region; The two ends, front and back end of described extraction inner region are respectively arranged with the first extraction flange and the second extraction flange; Described second extraction flange coordinates with described outer tube, and and between described outer tube, be provided with the 4th sealing ring; Described extraction outskirt is provided with first seal area corresponding with described second extraction flange;
The external diameter of described extraction inner region is less than the diameter of described outer tube; Described extraction inner region circumferentially with is axially evenly equipped with multiple extraction endoporus;
The center line of described Z-direction depression bar can be positioned at on described first extraction flange and equidistant virtual of the second extraction flange opposing end surface.
For ease of a certain Z-direction depression bar of survey calculation on the impact of extraction, described first extraction flange coordinates with described outer tube, and and between described outer tube, be provided with the 5th sealing ring; Described extraction outskirt is provided with second seal area corresponding with described first extraction flange.
Preferably, the aperture of described extraction exit orifice is greater than the aperture of described extraction endoporus; The distribution density of described extraction exit orifice is greater than the distribution density of described extraction endoporus; In described extraction outskirt, outside the first seal area and the second seal area, the first axial hole heart between each described extraction exit orifice is apart from being not less than 5mm; The second axial hole heart between each described extraction endoporus is apart from the twice being described first axial hole heart distance.
Preferably, the extraction outskirt of described outer tube is evenly equipped with 18 described extraction exit orifice in a circumferential direction; The extraction inner region of described 3rd adapter is evenly equipped with 4 described extraction endoporus in a circumferential direction; The aperture of described extraction exit orifice is not more than 1.5mm; The aperture of described extraction endoporus is not less than 2mm; Described first axial hole heart distance is 5mm; Described second axial hole heart distance is 10mm.
Preferably, bonded washer is provided with between the front end face of described first joint and described interior pipe.
For ease of operation, the endoporus aperture of described outstanding cover is greater than the external diameter of described outer tube holder.
The present invention discloses a kind of multi-scenarios method coal bed gas extraction simulation experiment method, comprise the following steps:
1, early-stage preparations
1a) test the property of water-bearing of coal sample used, then add certain water according to coal sample quality and make predetermined moisture content;
1b) in test piece box in coal rock layer forming process, sensor installation and extraction outer tube simultaneously, the back-end closure of described extraction outer tube, front opening; Described outer tube is provided with the extraction outskirt that position is corresponding with test piece box each Z-direction depression bar; Described extraction outskirt is provided with some extraction exit orifice;
1c) sealed test piece case installed by cover plate, and connects sensor and be wired to computer;
1d) test piece box is placed in loading system, then assembles in extraction in extraction outer tube and manage; In extraction, pipe comprises the first adapter and the 3rd adapter, and optionally one or more second adapter; Described first adapter, the second adapter and the 3rd adapter can be threaded front and back successively, and connecting thread has interchangeability; What described first adapter, the second adapter and the 3rd were taken over is provided with sealing ring in conjunction with end; The external diameter of described first adapter and the second adapter is less than the internal diameter of described outer tube; Described first adapter and the second adapter are provided with through hole vertically; Described 3rd adapter is provided with the blind hole of front opening back-end closure vertically; Described 3rd adapter is provided with extraction inner region; The two ends, front and back end of described extraction inner region are respectively arranged with the first extraction flange and the second extraction flange; Described second extraction flange coordinates with described outer tube, and and between described outer tube, be provided with the 4th sealing ring; Described extraction outskirt is provided with first seal area corresponding with described second extraction flange; The external diameter of described extraction inner region is less than the diameter of described outer tube; Described extraction inner region circumferentially with is axially evenly equipped with multiple extraction endoporus;
1e) at the outlet of the first adapter wide range Gas-Flow gauge in parallel and small-range Gas-Flow gauge; Test piece box is connected with gas source of the gas;
2, gas adsorption
Close each valve with seal case, start data collecting system, then start three-dimensional stress loading system, predetermined stress level is applied to each depression bar of test piece box, adopt deeply to simulate; Open vacuum pump to vacuumize coal seam, reach 1 × 10 to make the pressure in test piece box
2pa; Open gas gas cylinder after one hour to inflate, the blowing pressure is 1.2MPa, and inflationtime is 48 hours;
3, gas pumping
Open drainage tube valve, each Parameters variation of omnidistance detection and gas flow change: first open Mass Flow Meter, treat that flow is reduced in the range of small-range Gas-Flow gauge, close wide range Gas-Flow gauge, open small-range Gas-Flow gauge; This process gas source can be closed, and also can be stable at predetermined output pressure always;
4, single test is terminated
When having gas source: closed gas system, three-dimensional is stopped to load; Continue firedamp drainage, until desorption of mash gas is complete in test piece box, stop data collecting system, terminate test;
During without gas source: in test piece box, desorption of mash gas is discharged and completely then stopped three-dimensional loading, and stops data collecting system, terminates test;
5, complete with other tests of group
Change simulation adopt dark, extraction length or extraction point wherein one of test parameters, and keep other test parameters constant, or change extraction length and extraction point simultaneously and keep simulation to adopt deeply, repetition above-mentioned steps 2-4.
Preferably, step 1a) in, coal sample moisture content is 5%.
The present invention also discloses coal bed gas extraction test method in a kind of multiple seam unitized production process, comprise step as follows:
1, early-stage preparations
1a) test the property of water-bearing of coal sample used, then add certain water according to coal sample quality and make predetermined moisture content; Test specimen is made multiple seam test specimen, and lay multiple oil pressure bag in lower coal seam, oil pressure bag is connected to the data acquisition hole of the left plate of casing;
1b) sealed test piece case installed by cover plate, and connects sensor and be wired to computer; In the middle part of test piece box, just arrange the second joint to place with each Y-direction depression bar, be connected inside each second joint with rubber hose coupling, rubber hose coupling is taken over side direction and is connected, and side direction adapter is densely covered with multiple side direction drainage holes;
1c) connect the 3rd Gas-Flow gauge in the outer end of each second joint; Test piece box is connected with gas source of the gas; Each oil pressure bag is connected to its external control piper;
2, gas adsorption
Close each valve with seal case, start data collecting system, then start three-dimensional stress loading system, predetermined stress level is applied to each depression bar of test piece box, adopt deeply to simulate; Open vacuum pump to vacuumize coal seam, reach 1 × 10 to make the pressure in test piece box
2pa; Open gas gas cylinder after one hour to inflate, the blowing pressure is 1.2MPa, and inflationtime is 48 hours;
3, gas pumping
Open 4 the 3rd Gas-Flow gauge simultaneously, detect the gas flow change of the inner gas pressure in coal seam and STRESS VARIATION and each extraction point, after stability of flow, with 1.44h or 0.72h or 0.48h or 0.36h for interval emptying each oil pressure bag one by one from front to back, till all oil pressure bags are emptying, to simulate seam mining speed in actual condition; The change of uninterrupted gas pressure, stress of coal seam and each extraction point flow of monitoring in upper coal seam and lower coal seam in this course; In this process, gas source pressure is stable at always adopts deeply corresponding pressure with simulating;
4, single test is terminated
Closed gas system, stops three-dimensional loading; Continue to open methane gas extraction pipeline firedamp drainage, until coal bed gas desorb is complete in casing, stop data collecting system, terminate experiment;
5, change simulation adopt dark or model face propulsion speed wherein one of test parameters, and keep other test parameters constant, repeat above step 2-4.
The invention has the beneficial effects as follows:
1, the simulation of coal seam coal bed gas extraction can be carried out in laboratory, thus provide theoretical direction for field operation;
2, the coal bed gas extraction situation under multiple seam and single coal seam state when multiple physical field (stress field, crack field, seepage field) is coupled can be simulated;
3, the Changing Pattern of coal bed gas extraction rate under mining influence can be simulated, can simulate especially in protective coat extracted mode, the extracting result change of protected seam;
3, this simulation experiment method, consider the Changing Pattern of coal bed gas flow regime in coal seam when multiple physical field intercouples, reproduce the situation of change of coal seam parameter in Engineering Disturbance situation, the change of stress field, crack field, seepage field, thermal field can be studied, analyze coal bed gas and to flow the temporal-spatial evolution and the regularity of distribution that are coupled with coal and rock crack.
4, equipment operating is convenient, and automaticity is high.
Accompanying drawing explanation
Fig. 1 is the structural representation of the embodiment of the invention.
Fig. 2 is the plan structure schematic diagram of Fig. 1.
Fig. 3 is the left TV structure schematic diagram of Fig. 1.
Fig. 4 is the partial enlarged drawing at I place in Fig. 1.
Fig. 5 is the partial enlarged drawing at II place in Fig. 1.
Fig. 6 is the partial enlarged drawing at III place in Fig. 1.
Fig. 7 is another structural representation of inner and outer tubes in the embodiment of the invention.
Fig. 8 is the A-A sectional view of Fig. 6.
Fig. 9 is the pipeline structure schematic diagram of outlet side in the extraction test of the embodiment of the invention.
Figure 10 is the pipeline structure schematic diagram of gas source of the gas in the embodiment of the invention.
Figure 11 is that in the extraction test of the embodiment of the invention, extraction point is positioned at the structural representation below the 3rd Z-direction pressure head.
Figure 12 is that in the extraction test of the embodiment of the invention, extraction point is positioned at the structural representation below the second Z-direction pressure head.
Figure 13 is that in the extraction test of the embodiment of the invention, extraction point is positioned at the structural representation below the first Z-direction pressure head.
Figure 14 is the stress in coal bed distribution schematic diagram in work plane front in actual condition.
Figure 15 adopts dynamic simulated extraction test schematic diagram in the embodiment of the invention.
Figure 16 is the left TV structure schematic diagram after Figure 15 removes test specimen.
Figure 17 is the partial enlarged drawing at IV place in Figure 16.
Figure 18 is the pipeline structure schematic diagram of the second joint outlet side in coal bed gas extraction simulated test in multiple seam unitized production process of the present invention.
Detailed description of the invention
Below in conjunction with drawings and Examples, the invention will be further described:
As shown in Figures 1 to 6, a kind of multi-scenarios method coal-bed gas exploitation physical simulation experiment system, comprise test piece box 1, the upper boxboard of test piece box 1 is disposed with the first Z-direction depression bar 2a, the second Z-direction depression bar 2b, the 3rd Z-direction depression bar 2c and the 4th Z-direction depression bar 2d after the past, each Z-direction depression bar is all fixed with Z-direction pressing plate 3, right boxboard is provided with four Y-direction depression bars 4 and Y-direction pressing plate 5, rearing-box plate is provided with an X to depression bar 6 and X to pressing plate 7.Z-direction pressing plate 3, Y-direction pressing plate 5 and X are all positioned at test piece box 1 to pressing plate 7.
The bottom of test piece box 1 is provided with air permeable steel plate 25 and air flue 26, and air permeable steel plate 25 covers on air flue 26, and the import of air flue 25 is provided with interior plug 27.
The left boxboard space outside of test piece box 1 is fixedly connected with the first backing plate 28, and left boxboard is provided with interface 29 between the interval of each first backing plate 28, is provided with sensor first joint 30 in interface 29.
The front boxboard of test piece box 1 is provided with stair-stepping aspis 9, has been bolted to connection outstanding cover 10 in aspis 9, gives prominence to and is provided with the first sealing ring 8a between cover 10 and the cascaded surface of front boxboard.
The endoporus of outstanding cover 10 is pre-large post-small shoulder hole, is provided with the outer tube holder 11 that shape is corresponding with shoulder hole in this shoulder hole.The endoporus aperture of outstanding cover 10 is greater than the external diameter of described outer tube holder 11.
The second sealing ring 8b is provided with between the cascaded surface of outstanding cover 10 and outer tube holder 11.Be threaded in the endoporus of outer tube holder 11 outer tube 12, and outer tube 12 extends in test piece box 1.
The front end face of outstanding cover 10 has been bolted mounting flange 13, and be provided with the 3rd sealing ring 8c between outer tube holder 11 and mounting flange 13, the front end of mounting flange 13 is provided with flange boss 13a, and the cylindrical of flange boss 13a is provided with screw thread.
The back-end closure of outer tube 12, front opening.Outer tube 12 is provided with the extraction outskirt 12a that position is corresponding with each Z-direction depression bar, extraction outskirt 12a is provided with some extraction exit orifice 14a.
Interior pipe 15 is provided with in outer tube 12 and mounting flange 13.Interior pipe 15 comprises the first adapter 15a and the 3rd adapter 15c, and optional one or more second adapter 15b.First adapter 15a, the second adapter 15b and the 3rd adapter 15c can be threaded front and back successively, and connecting thread has interchangeability.First adapter 15a, the second adapter 15b and the 3rd adapter 15c are provided with sealing ring 8f in conjunction with end.The external diameter of the first adapter 15a and the second adapter 15b is less than the internal diameter of outer tube 12;
First adapter 15a companion flange boss 13a place is provided with defining flange 15a1, and the first adapter 15a is provided with screw thread at the front end 15a2 cylindrical of defining flange 15a1.Be combined with in the front end endoporus of the first adapter 15a between the first joint 16, first joint 16 and the front end face of interior pipe 15 and be provided with bonded washer 18.
The external screw thread of defining flange 15a1 and flange boss 13a is combined with nut 19.
First adapter 15a and the second adapter 15b is provided with through hole vertically, and the 3rd adapter 15c is provided with the blind hole of front opening back-end closure vertically.
3rd adapter 15c is provided with extraction inner region 15c1, and the two ends, front and back end of extraction inner region 15c1 are respectively arranged with the first extraction flange 15c2 and the second extraction flange 15c3.
In the present embodiment, the 3rd adapter 15c comprises two kinds of basic structures, and wherein I type basic structure is that the second extraction flange 15c3 coordinates with outer tube 12, and and between outer tube 12, be provided with the 4th sealing ring 8d; Meanwhile, the first extraction flange 15c2 coordinates with outer tube 12, and and between outer tube 12, be provided with the 5th sealing ring 8e; Accordingly, extraction outskirt 12a is provided with the second seal area 12b corresponding with the first extraction flange 15c2, and the first seal area 12c corresponding with the second extraction flange 15c3.As shown in Figure 6.
The II type basic structure of the 3rd adapter 15c is, be only that the second extraction flange 15c3 being positioned at rear end coordinates with outer tube and arranges sealing ring, but the first extraction flange 15c2 external diameter being positioned at front end is less than the internal diameter of outer tube 12.As shown in Figure 7.
For the 3rd adapter 15c of I type structure, the spacing of the first extraction flange 15c2 and the second extraction flange 15c3 opposing end surface forms extraction distance L; For the 3rd adapter 15c of II type structure, its extraction distance is adjustable according to the quantity of the second adapter 15b.
The external diameter of extraction inner region 15c1 is less than the diameter of outer tube 12; Extraction inner region 15c1 circumferentially with is axially evenly equipped with multiple extraction endoporus 14b.
The center line of each Z-direction depression bar can be positioned at on the first extraction flange 15c2 and the equidistant virtual face 17 of the second extraction flange 15c3 opposing end surface.
The extraction outskirt 12a of outer tube 12 is evenly equipped with 18 extraction exit orifice 14a in a circumferential direction, and the extraction inner region 15c1 of the 3rd adapter 15c is evenly equipped with 4 extraction endoporus 14b in a circumferential direction, as shown in Figure 8.The aperture of extraction exit orifice 14a is 1.5mm, and the aperture of extraction endoporus 14b is 2mm.
In extraction outskirt 12, outside the first seal area 12c and the second seal area 12b, the first axial hole heart between each extraction exit orifice 14a is apart from being 5mm, and the second axial hole heart distance between each extraction endoporus 14b is 10mm.
Reaction frame in multi-scenarios method coal mine dynamic disaster large scale mock up test system disclosed in above-mentioned pilot system and cn102621232A and frame with the use of, multiple extraction modeling scheme can be designed, to complete multi-scenarios method coal-bed gas exploitation simulated test.Table one lists the optional testing program of part, and wherein testing program 1,2,3 and 4 forms one group of simulated test, and scheme 3,5,6 forms one group of simulated test, and scheme 3,7,8,9 forms one group of simulated test.In test parameters cited by table one, simulation is adopted between dark and gas pressure has corresponding relation, obtains by conventionally calculation.
The test procedure of each group of simulated test is as follows:
1, early-stage preparations
1a) test the property of water-bearing of coal sample used, then add certain water according to coal sample quality and make predetermined moisture content, this simulation coal seam moisture content is 5%;
1b) in test piece box in coal rock layer forming process, sensor installation, extraction outer tube 12 and mounting flange simultaneously;
1c) sealed test piece case installed by cover plate, and connects sensor and be wired to computer;
1d) test piece box is pushed into the base precalculated position of loading system, installs reaction frame, then assemble pipe in extraction; Wherein, according to different extractions point, select the second adapter 15b of varying number, as pipe interior in scheme 1 only comprises the first adapter 15a and the 3rd adapter 15c, to make the center line 2a1 of the first Z-direction depression bar 2a be positioned on virtual face 17, as shown in figure 13; Also can select a second adapter 15b, make it be connected with the first adapter 15a and the 3rd adapter 15c, to make the center line of the second Z-direction depression bar 2b be positioned on virtual face 17, as shown in figure 12;
1e) connect the first baroceptor 20, first valve 21, threeway 23 successively in the outer end of the first joint 16; First path of threeway 23 is connected with the second valve 22,500L/min range Gas-Flow gauge 41, alternate path is connected with the 3rd valve 24 and 50L/min range Gas-Flow gauge 42, as shown in Figure 9; The second baroceptor 31, fine tuning valve 32 and gas gas cylinder 33 is connected successively at interior plug 27 place, length of pipe wherein between interior plug 27 and baroceptor 31 is less than 0.2m, length of pipe between baroceptor 31 and fine tuning valve 32 is not less than 3m, length of pipe between fine tuning valve 32 and gas gas cylinder 33 is less than 0.5m, as shown in Figure 10.
2, gas adsorption
Close each valve with seal case, start data collecting system, then three-dimensional stress loading system is started, apply predetermined stress level, adopt deeply, as shown in table one scheme 1 to simulate, the power of each Y-direction depression bar 4 is 3.6MPa, X is 1.2MPa to the power of depression bar 6, and the power of the first Z-direction depression bar 2a, the second Z-direction depression bar 2b, the 3rd Z-direction depression bar 2c and the 4th Z-direction depression bar 2d is respectively 1.6MPa, 4.7MPa, 3.1MPa and 3.1MPa, adopts deeply to simulate 1100m; Open vacuum pump to vacuumize coal seam, reach 1 × 10 to make the pressure in test piece box
2pa; Open gas gas cylinder after one hour to inflate, the blowing pressure is 1.2MPa, and inflationtime is 48 hours.
3, gas pumping
Open drainage tube valve, each Parameters variation of omnidistance detection and gas flow change: first open 500L/min range flow meter, treat that flow is reduced to 50L/min, close the valve of 500L/min side, open the valve of 50L/min side.This process gas source (gas pot) can be closed, and also can be stable at predetermined output pressure 1.2MPa always.
4, desorption of mash gas
When having gas source: closed gas system, three-dimensional is stopped to load; Continue firedamp drainage, until desorption of mash gas is complete in test piece box, stop data collecting system, terminate test;
During without gas source: in test piece box, desorption of mash gas is discharged and completely then stopped three-dimensional loading, and stops data collecting system, terminates test.
5, complete with other tests of group
Change simulation adopt dark, extraction length or extraction point wherein one of test parameters, and keep other test parameters constant, as the quantity by increasing and decreasing the second adapter 15b or the length changing the 3rd adapter 15c, to change extraction fragment position, even if the center line of another Z-direction depression bar is positioned on virtual face 17, as shown in Figure 11, Figure 12 and Figure 13, repeat above-mentioned steps 2-4, complete other testing programs with group, to simulate the extraction process evolution rule under different condition.
In actual condition, work plane front coal body has different pressure spans, and as shown in figure 14, Tu14Zhong, a-quadrant is distressed zone, and B region is area of stress concentration, and C region is virgin stress district, and δ H is virgin stress district.In extraction test, according to the stress rule shown in figure, different load can be applied, to simulate different stress areas to the first Z-direction depression bar 2a, the second Z-direction depression bar 2b, the 3rd Z-direction depression bar 2c and the 4th Z-direction depression bar 2d.As shown in Table 1, the first Z-direction depression bar 2a is for simulating distressed zone, and the second Z-direction depression bar 2b is for simulating area of stress concentration, and the 3rd Z-direction depression bar 2c and the 4th Z-direction depression bar 2d is for simulating virgin stress district.
Table one: extraction simulated test scheme
In other testing programs, also can carry out the test of different gas pressure and different water cut, to simulate actual condition more really, thus draw extraction rule more accurately.
In other testing programs, the 3rd adapter 15c also can adopt II type basic structure, by adjusting the position in virtual face 17, to realize carrying out extraction test to one or several extraction district 12a, thus changes extraction length and extraction point.
According to theory of similarity principle, dimensions length ratio (likelihood ratio) is constant, that is:
Wherein, D is working site drainage tube external diameter; D is the outer tube caliber of simulation; H is the drainage holes spacing of working site coal seam thickness or working site; H is the height of test piece box; C is the likelihood ratio, is constant.
Therefore according to above formula, the outer tube external diameter of test can be calculated as the case may be.
In other testing programs, same extraction position can be carried out and adopt the extraction of different extraction length to test, to study bearing stress influence area size and extraction segment length to the affecting laws of extraction process; The extraction test of the 12c position, difference first seal area of II type basic structure can be carried out, with the change of research work face concordant hole length to the affecting laws of extraction rate change.
By carrying out organizing testing program above more, to the inner gas pressure in coal seam in extraction process and temperature Real-Time Monitoring, in conjunction with gas flow situation of change, the data of computer acquisition carry out graphical treatment by software, thus the temporal and spatial evolution of gas pressure and temperature in coal bed gas extraction process can be inquired into, during research extraction, territory, different stressed zone is to the affecting laws of extraction efficiency, and coal seam percolating network when building different extraction position.
Simultaneously, reaction frame in multi-scenarios method coal mine dynamic disaster large scale mock up test system disclosed in above-mentioned pilot system and cn102621232A and frame with the use of, multiple extraction modeling scheme can be designed, to complete coal bed gas extraction simulated test in multiple seam unitized production process.List some optional testing programs in table two, wherein testing program 1,2,3,4 forms one group of simulated test, and scheme 3,6,7,8 forms one group of simulated test.In test parameters cited by table one, simulation is adopted between dark and gas pressure has corresponding relation, obtains by conventionally calculation.
The test procedure of each group of simulated test is as follows:
1, early-stage preparations
1a) test the property of water-bearing of coal sample used, then add certain water according to coal sample quality and make predetermined moisture content, this simulation coal seam moisture content is 5%; Test specimen is made multiple seam test specimen, as shown in figure 15, from top to bottom, be followed successively by mantlerock 42, upper coal seam 43, lower rock stratum 44 and lower coal seam 45, meanwhile, lay oil pressure bag 40 in lower coal seam; Upper coal seam is for simulating protected seam, and lower coal seam is for simulating topping;
1b) sealed test piece case installed by cover plate, and connects sensor and be wired to computer; As shown in figure 16, the sensor connector just right with each Y-direction depression bar 4 in the middle part of test piece box is replaced by the second joint 34, and be connected with rubber hose coupling 35 inside each second joint 34, rubber hose coupling 35 is connected with side direction adapter 36, side direction adapter 36 is densely covered with multiple side direction drainage holes 36a, as shown in figure 17;
1c) connect the 3rd baroceptor 37, the 4th valve 38 and the 3rd Gas-Flow gauge 39 successively in the outer end of each second joint 34, as shown in figure 18; Baroceptor 31, fine tuning valve 32 and gas gas cylinder 33 is connected successively at interior plug 27 place, length of pipe wherein between interior plug 27 and baroceptor 31 is less than 0.2m, length of pipe between baroceptor 31 and fine tuning valve 32 is not less than 3m, and the length of pipe between fine tuning valve 32 and gas gas cylinder 33 is less than 0.5m; Each oil pressure bag is connected to its external control piper.
2, gas adsorption
Close each valve with seal case, start data collecting system, then three-dimensional stress loading system is started, apply predetermined stress level, adopt deeply, as shown in table two scheme 1 to simulate, the power of each Y-direction depression bar 4 is 3.6MPa, X is 1.2MPa to the power of depression bar 6, and the power of each Z-direction depression bar is 3.1MPa, with simulate 1100m adopt deeply adopt dark; Open vacuum pump to vacuumize coal seam, reach 1 × 10 to make the pressure in test piece box
2pa; Open gas gas cylinder after one hour to inflate, the blowing pressure is 1.2MPa, and inflationtime is 48 hours.
3, gas pumping
Open 4 the 4th valves simultaneously, detect the gas flow change of the inner gas pressure in coal seam and STRESS VARIATION and each extraction point, after stability of flow, take 1.44h as interval emptying each oil pressure bag one by one from front to back, till all oil pressure bags are emptying, to simulate in actual condition, the exploitation rate of coal seam 1m/ days; The change of uninterrupted gas pressure, stress of coal seam and each extraction point flow of monitoring in upper coal seam and lower coal seam in this course; In this process, gas source pressure is stable at this predetermined output pressure of 1.2MPa always.Extraction until last oil pressure bag emptying after, 4 the 3rd Gas-Flow gauge 39 flows are all basicly stable.
4, experiment terminates
Closed gas system, stops three-dimensional loading; Continue to open methane gas extraction pipeline firedamp drainage, until coal bed gas desorb is complete in casing, stop data collecting system, terminate experiment;
5, change simulation adopt dark or model face propulsion speed wherein one of test parameters, and keep other test parameters constant, repeat above step 2-4.
Table two: adopt dynamic simulated testing program
In table two, each testing program all carries out extraction in the region corresponding with each Y-direction depression bar, in other testing programs, also can design more extraction point, to improve test accuracy.
In table two, 1m/ days, 2m/ days, 3m/ days, a 4m/ days fltting speed correspond respectively to every 1.44h (86.4min), 0.72h (43.2min), the emptying oil pressure bag of 0.48h (28.8min), 0.36h (21.6min).
By carrying out organizing testing program above more; to the Real-Time Monitoring of coal seam inside gas pressure and stress of coal seam in extraction process; in conjunction with gas flow situation of change; thus inquire in multiple seam unitized production process; the dynamic dynamic evolution rule of protected seam extraction; research protected seam variation of stress, Gas-Flow to extraction efficiency change rule, build the coal seam percolating network of protected seam extraction in mining active process.
More than describe preferred embodiment of the present invention in detail.Should be appreciated that those of ordinary skill in the art just design according to the present invention can make many modifications and variations without the need to creative work.Therefore, all technician in the art, all should by the determined protection domain of claims under this invention's idea on the basis of existing technology by the available technical scheme of logical analysis, reasoning, or a limited experiment.
Claims (2)
1. a coal bed gas extraction test method in multiple seam unitized production process, is characterized in that: comprise step as follows:
1, early-stage preparations
1a) test the property of water-bearing of coal sample used, then add certain water according to coal sample quality and make predetermined moisture content; Test specimen is made multiple seam test specimen, and lay multiple oil pressure bag in lower coal seam, oil pressure bag is connected to the data acquisition hole of the left plate of casing;
1b) on the upper boxboard of test piece box, set gradually the first Z-direction depression bar, the second Z-direction depression bar, the 3rd Z-direction depression bar and the 4th Z-direction depression bar from front to back, each Z-direction depression bar is all fixed with Z-direction pressing plate, right boxboard is arranged 4 Y-direction depression bars and Y-direction pressing plate, rearing-box plate is arranged 1 X to depression bar and X to pressing plate;
Sealed test piece case installed by cover plate, and connects sensor and be wired to computer; In the middle part of test piece box, just arranging 4 joints respectively to locating with 4 Y-direction depression bars, being connected inside 4 joints with rubber hose coupling, rubber hose coupling is taken over side direction and is connected, and side direction adapter is densely covered with multiple side direction drainage holes;
1c) connect Gas-Flow gauge respectively in the outer end of 4 joints; Test piece box is connected with gas source of the gas; Each oil pressure bag is connected to its external control piper;
2, gas adsorption
Close each valve with seal case, start data collecting system, then start three-dimensional stress loading system, to depression bar, predetermined stress level is applied to 4 Y-direction depression bars of test piece box, 4 Z-direction depression bars and 1 X, adopt deeply to simulate; Open vacuum pump to vacuumize coal seam, reach 1 × 10 to make the pressure in test piece box
2pa; Open gas gas cylinder after one hour to inflate, the blowing pressure is 1.2MPa, and inflationtime is 48 hours;
3, gas pumping
Open 4 Gas-Flow gauge simultaneously, detect the gas flow change of the inner gas pressure in coal seam and STRESS VARIATION and each extraction point, after stability of flow, with 1.44h or 0.72h or 0.48h or 0.36h for interval emptying each oil pressure bag one by one from front to back, till all oil pressure bags are emptying, to simulate seam mining speed in actual condition; The change of uninterrupted gas pressure, stress of coal seam and each extraction point flow of monitoring in upper coal seam and lower coal seam in this course; In this process, gas bleed pressure is stable at always adopts deeply corresponding pressure with simulating;
4, single test is terminated
Closed gas gas cylinder, stops three-dimensional stress loading; Continue to open methane gas extraction pipeline firedamp drainage, until coal bed gas desorb is complete in casing, stop data collecting system, terminate experiment;
5, change simulation adopt dark or model face propulsion speed wherein one of test parameters, and keep other test parameters constant, repeat above step 2-4.
2. coal bed gas extraction test method in a kind of multiple seam unitized production process as claimed in claim 1, is characterized in that: step 1a) in, coal sample moisture content is 5%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310025114.7A CN103089295B (en) | 2013-01-23 | 2013-01-23 | Coal bed gas extraction test method in multiple seam unitized production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310025114.7A CN103089295B (en) | 2013-01-23 | 2013-01-23 | Coal bed gas extraction test method in multiple seam unitized production process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103089295A CN103089295A (en) | 2013-05-08 |
| CN103089295B true CN103089295B (en) | 2015-10-28 |
Family
ID=48202364
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310025114.7A Active CN103089295B (en) | 2013-01-23 | 2013-01-23 | Coal bed gas extraction test method in multiple seam unitized production process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103089295B (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103114827B (en) * | 2013-01-23 | 2016-09-28 | 重庆大学 | Multi-scenarios method coal bed gas extraction simulation experiment method |
| CN103696746B (en) * | 2013-12-25 | 2016-04-20 | 辽宁工程技术大学 | A kind of microwave excitation Desorption And Seepage of Coalbed Methane experimental facilities |
| CN104569345B (en) * | 2014-12-18 | 2017-01-04 | 西安科技大学 | Two-dimensional solid steam multi-scenarios method physical simulation method |
| CN104832176B (en) * | 2015-03-18 | 2016-10-12 | 西安科技大学 | A kind of multiplex method for arranging in lane of low air permeability coal seam group's pressure relief gas pumping mining suction road |
| CN105807006B (en) * | 2016-05-04 | 2018-11-02 | 重庆大学 | Fissure-plane liquid flow simulating test method |
| CN106771063B (en) * | 2016-12-08 | 2019-01-11 | 重庆大学 | Multiple superposed gas system vertical well exploits simulation experiment method |
| CN106593369B (en) * | 2016-12-08 | 2019-02-15 | 重庆大学 | Multiple superposed gas system CO2 is layered displacement CH4 simulation experiment method |
| CN106771064B (en) * | 2016-12-08 | 2019-01-11 | 重庆大学 | Multiple superposed gas system vertical well exploits simulated test facility |
| CN106812523B (en) * | 2017-01-22 | 2020-04-07 | 中国地质大学（北京） | Physical simulation device for multi-coal-bed gas well drainage and mining and experimental method thereof |
| CN107120112B (en) * | 2017-05-05 | 2020-04-03 | 中国石油大学(北京) | Multi-coal-bed gas combined mining experimental device |
| CN108362853A (en) * | 2018-02-08 | 2018-08-03 | 重庆大学 | A kind of coal containing methane gas ultra-high pressure water fluid jet slot analog simulation system and method |
| CN108915650B (en) * | 2018-07-10 | 2020-12-08 | 中国地质大学（北京） | Device and method for simulating differential pressure drop in coal bed gas drainage and mining process |
| CN109060507B (en) * | 2018-08-20 | 2020-08-07 | 山东科技大学 | Method for testing influence of coal bed gas extraction on deformation of coal bed roof under action of non-uniform load |
| CN109446602B (en) * | 2018-10-15 | 2022-09-09 | 内蒙古科技大学 | Numerical test method for extracting gas from ultra-thick coal seam through ground vertical drilling |
| CN109469474B (en) * | 2018-12-05 | 2021-11-02 | 中国矿业大学(北京) | Device and method for simultaneously measuring gas pressure of multiple coal seams based on downward cross-layer drilling |
| CN110308259B (en) * | 2019-07-02 | 2021-02-02 | 中国矿业大学 | Multi-field coupling fracturing-displacement cooperative strengthening gas extraction test device |
| CN110299059A (en) * | 2019-07-02 | 2019-10-01 | 中国矿业大学 | A kind of projecting coal bed mash gas extraction and the test integrated experimental rig of extinction |
| CN110700795A (en) * | 2019-09-06 | 2020-01-17 | 太原理工大学 | Physical experiment box body for gas extraction of multi-branch horizontal well |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101392638A (en) * | 2008-11-03 | 2009-03-25 | 中国海洋石油总公司 | Simulating device for solid-state mining experiment of gas hydrate |
| RU2422620C1 (en) * | 2010-02-24 | 2011-06-27 | Государственное унитарное предприятие "Институт проблем транспорта энергоресурсов" | Procedure for protection of centrifugal pump from deposit of salts |
| CN102564725A (en) * | 2012-03-12 | 2012-07-11 | 徐州中矿安达矿山科技有限公司 | Simulation experiment device of three-dimensional gas extraction worked-out area flow field |
| CN103114827A (en) * | 2013-01-23 | 2013-05-22 | 重庆大学 | Multi-field coupling coal bed methane extraction simulation testing method |
-
2013
- 2013-01-23 CN CN201310025114.7A patent/CN103089295B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101392638A (en) * | 2008-11-03 | 2009-03-25 | 中国海洋石油总公司 | Simulating device for solid-state mining experiment of gas hydrate |
| RU2422620C1 (en) * | 2010-02-24 | 2011-06-27 | Государственное унитарное предприятие "Институт проблем транспорта энергоресурсов" | Procedure for protection of centrifugal pump from deposit of salts |
| CN102564725A (en) * | 2012-03-12 | 2012-07-11 | 徐州中矿安达矿山科技有限公司 | Simulation experiment device of three-dimensional gas extraction worked-out area flow field |
| CN103114827A (en) * | 2013-01-23 | 2013-05-22 | 重庆大学 | Multi-field coupling coal bed methane extraction simulation testing method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103089295A (en) | 2013-05-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103089295B (en) | Coal bed gas extraction test method in multiple seam unitized production process | |
| CN103114870B (en) | Multi-field coupling coal bed methane extraction physical simulation testing system | |
| CN103089254B (en) | Multi-scenarios method coal-bed gas exploitation physical simulation experiment pipe | |
| CN103114827B (en) | Multi-scenarios method coal bed gas extraction simulation experiment method | |
| CN102735548B (en) | Multifunctional true triaxial flow solid coupling test system | |
| CN102735547B (en) | Coal-rock hydraulic fracturing testing method under true triaxial state | |
| CN104458534B (en) | One adds coal measure strata fracture seepage simulation test device and method under unloading condition | |
| CN102735549B (en) | Multifunctional true triaxial flow solid coupling pressure chamber | |
| CN101581234B (en) | Comprehensive underground test method for deformation and damage of terranes of mining top plate and mining bottom plate of coal bed | |
| WO2015158153A1 (en) | Water conservation method used in coal mining process | |
| CN204327082U (en) | A kind of coal measure strata structure large scale fracture seepage physical simulation experimental rig | |
| CN105021662B (en) | Adopt workplace regimen real-time dynamic monitoring test unit and test method | |
| CN103711480B (en) | Horizontal drilling assay device | |
| CN103591922B (en) | Short range seam mining upper Seam Floor Failure degree of depth radon gas detection method | |
| Hu et al. | Methane extraction from abandoned mines by surface vertical wells: a case study in China | |
| CN106869997A (en) | A kind of colliery multi-aquifer prevention and controls | |
| CN104453878A (en) | Multi-element gas displacement coal bed methane testing device based on process real-time tracking control | |
| Huang et al. | Analytical and experimental study of water seepage propagation behavior in the fault | |
| CN113360592A (en) | Method for pre-warning water inrush danger of coal seam roof in N00 construction method based on micro-seismic monitoring | |
| CN109655494A (en) | A kind of mining overburden solid-liquid coupling three dimensional lossless monitoring system and method | |
| CN103670511B (en) | A kind of analysis calculation method of roof strata level of breakage | |
| CN201517369U (en) | Multi-angle horizontal branch well natural gas extraction simulator | |
| Xue et al. | Numerical investigation on overburden migration behaviors in stope under thick magmatic rocks | |
| CN114087019B (en) | Method for preventing and controlling huge-thickness heterogeneous sandstone water damage area | |
| Guo et al. | Research on optimization of key areas of drainage borehole sealing in ultrathick coal seam |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |