CN108301862B - A kind of new method preventing spontaneous combustion of remaining coal to goaf pressure injection retardant - Google Patents
A kind of new method preventing spontaneous combustion of remaining coal to goaf pressure injection retardant Download PDFInfo
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- CN108301862B CN108301862B CN201810367253.0A CN201810367253A CN108301862B CN 108301862 B CN108301862 B CN 108301862B CN 201810367253 A CN201810367253 A CN 201810367253A CN 108301862 B CN108301862 B CN 108301862B
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- retardant
- goaf
- injection
- pressure
- pressure injection
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F5/00—Means or methods for preventing, binding, depositing, or removing dust; Preventing explosions or fires
- E21F5/02—Means or methods for preventing, binding, depositing, or removing dust; Preventing explosions or fires by wetting or spraying
Abstract
The invention discloses a kind of new methods that spontaneous combustion of remaining coal is prevented to goaf pressure injection retardant, belong to coal mining technology field.Method includes the following steps: S1, carrying out height investigation to fissure zone and caving zone；S2, drill site is designed according to the height of fissure zone；S3, design and construction drill site and drilling are pressed, retardant injection device is installed；S4, water injection hole packer is put into drilling orifice；S5, retardant is added, to goaf pressure injection retardant；S6, stop pressure injection after having drilling and caving zone penetrates through.The present invention also provides the specific structures of retardant injection device；The fissure zone that the present invention utilizes exploitation process to generate, pass through arrangement drill site or high-order drill site, it drills into fissure zone, static pressure pressure injection retardant into goaf is relied on by retardant injection device after drilling and sealing, retardant sprinkling is uniform and does not influence normal coal mining activity, it is effectively prevent spontaneous combustion of remaining coal, is improved work efficiency.
Description
Technical field
The present invention relates to coal mining technology fields, and in particular to a kind of to prevent spontaneous combustion of remaining coal to goaf pressure injection retardant
New method.
Background technique
Coal is preservation in the earth's crust, is hold in stratiform by upper and lower rock stratum, and coal production process is by digging rock lane
Road arranges district sublevel entry in coal seam and cuts eye, then edge is cut eye and exploited outward, coal is produced, such as Fig. 3 institute into coal seam
Show, directly overlayed after coal extraction rock stratum above coal seam can inbreak form caving zone, then rock stratum up can generate crack
Fissure zone is formed, then rock stratum meeting bending subsidence formation warp damage up, caving zone are also named goaf, when due to exploitation not
Coal may be all recycled completely, some coal can be retained in goaf, and the coal left in goaf is due to work
Oxygen supply of the leaking out when back production of face, will be slow oxidation heat liberation, if cannot control in time, the heat accumulation of releasing makes to lose coal temperature
It increases, freely burning fire can be generated when reaching self-ignition point, gently then influences to produce, it is heavy then generate major industrial accident.
Retardant fire prevention is the method that coal mine commonly prevents and treats spontaneous combustionof coal, and cardinal principle is to spray retardant to coal
Solution, the characteristic of autoigniting for reducing coal reach fireproof purpose.Retardant, which prevents goaf from leaving spontaneous combustionof coal, at present mainly three
Kind method.The first is sprinkling retardant solution, this also most common one kind, it is installed in the district sublevel entry of stope
Retardant spray pump and resistanceization liquid case, fixation or the pistol of stope are connected to by pressure duct, from manually to
Retardant solution is sprayed on the Residual coal in goaf surface at working face rear portion, plays the role of preventing spontaneous combustionof coal；Second method is
Steam fog resistanceization, it is the intake entry installation retardant liquid atomizer pump and resistanceization liquid case in stope, working face into
Atomizer is installed at wind corner or force piece rear portion, and atomizer is connect by pressure duct with retardant liquid atomizer pump.
Retardant solution is brought into inside goaf after air inlet corner or bracket rear portion are atomized by spray head with distinguished and admirable, is moved through with distinguished and admirable
Resistanceization liquid steam fog is gradually fallen on the coal left inside goaf due to gravity in journey, plays the work of resistanceization spontaneous combustionof coal
With；The third method is pouring-in retardant fire prevention, it is to play concordant drilling to working face coal seam in the district sublevel entry of working face,
Then retardant solution is injected into still unquarried working face coal seam by way of coal-bed flooding, reduces the pyrophorisity of coal
Can, the purpose for preventing spontaneous combustion of remaining coal is played in the spontaneous combustionof coal performance decline being retained in goaf when waiting working face extractions.
Method one mainly sprays retardant to the subsequent something lost coal of bracket between force piece by man-hour manually hand-held spray gun,
This is presently the most common method.This is existing main problematic to has: first, due to the smaller sprinkling work of general standoff gap
Inconvenience, though can barely spirt go to will also result in that sprinkling is uneven, and resistanceization effect is poor；Second, if connected in a distance
Continue distance all very littles between multiple brackets, may cause can not spray retardant in this section of goaf, so that retardant is mined out
It is unevenly distributed in area, does not have the effect for preventing spontaneous combustion；Third is drenched out since the distance of sprinkling is very close compared with working face
Water flow can deteriorate the operating environment of working face.4th, if having in the caving zone in back production coal seam can not adopt and easily spontaneous combustion upper neighbour
Nearly coal seam increases heterogeneous goaf then losing coal as the back production of the working face adjacent coal seam can emit to fall on to be formed in goaf
Risk, current retardant method of fire protection can't resolve the problem；5th, retardant spraying operation is stope
Interior progress, inevitably conflict is generated with working surface production, influence normally to produce.
Method brings retardant steam fog into mined out second is that drive distinguished and admirable flowing by stope both ends leeway
Inside area, due to leaking out natively small in goaf so the retardant solution being brought into goaf is less, for goaf
Something lost coal is more, and the serious mine of spontaneous combustion is not able to satisfy fire protection requirement.
Method three due to be not yet back production coal body in injecting retarder, although this reduce goaf leave coal from
Performance is fired, while also reducing the combustibility of working face extraction coal, i.e., this method is to sacrifice Coal Quality as cost
's.And due to coal seam porosity and the difference of permeability size, lead to that retardant injects also can be uniform, and the effect of resistance has
Limit, this method is rarely employed at present, and the present invention proposes a kind of new method that spontaneous combustion of remaining coal is prevented to goaf pressure injection retardant, energy
It is enough to solve defect existing for above-mentioned three kinds of methods in the prior art.
Summary of the invention
The purpose of the invention is to overcome the problems of the prior art, provide a kind of prevents to goaf pressure injection retardant
The new method of spontaneous combustion of remaining coal,
The present invention provides a kind of new methods that spontaneous combustion of remaining coal is prevented to goaf pressure injection retardant, comprising the following steps:
S1, height investigation is carried out to fissure zone and caving zone, measures the fissure zone in goaf and the position of caving zone；
S2, drill site specification and spacing, dip angle of hole and depth are designed according to the height of fissure zone；
S3, it presses design and construction drill site and drills, after drilling construction, retardant injection device is installed；
S4, working face start back production, and after waiting old power stations, the water injection hole packer on retardant injection device is put into brill
In the aperture of hole；
S5, retardant is added to the storage bin of retardant injection device, opens the valve of baiting valve and static tube, adjust pressure
Beam amount, after pressure reaches the sealing of hole pressure of water injection hole packer, water injection hole packer seals drilling, and hole packer water outlet is beaten automatically
It opens, to goaf pressure injection retardant；
S6, the back production with working face stop pressure injection after having drilling and caving zone penetrates through, by retardant injection device
It moves on to next drill site and continues pressure injection work.
Preferably, the step S5 is to during the pressure injection retardant of goaf, paying attention to observing face roof and be used to
The water outlet status in the water drenching and goaf at the bracket rear of face roof is supported, uniform water drenching is answered on face roof top,
The valve for closing static tube immediately when the local water drenching of appearance increases suddenly or is discharged and increases suddenly, stops pressure injection.
Preferably, step S5 should add retardant to storage bin to during the pressure injection retardant of goaf.
5~7 drillings preferably, each drill site of multiple drill sites is constructed.
Preferably, boring direction is towards working face open-off cut eye direction, fissure zone of the drilling borehole bottom location in above goaf
It is interior, 75~94mm of boring aperture.
Preferably, the retardant injection device in step S3 includes: cabinet, static tube, distributive pipe, water injection hole packer, net
Lattice vertical clapboard, storage bin, baiting valve, pressure gauge, pressure reducing valve and flowmeter, the grid vertical clapboard are located in cabinet, and grid is perpendicular
Cabinet is divided into left box body and right case by partition, and static tube is connected with left box body, and distributive pipe is connected with right case, water filling
Hole packer is connect with distributive pipe by valve seal, and storage bin is located at the top of left box body, and storage bin passes through expects pipe and left box body
It is connected, baiting valve is located in expects pipe, and pressure gauge, pressure reducing valve and flowmeter are each provided on static tube.
Compared with prior art, the beneficial effects of the present invention are: the crack that the present invention utilizes working face extraction process to generate
Band is drilled into fissure zone, is injected after drilling and sealing by retardant by arranging drill site or high-order drill site in district sublevel entry
Device relies on static pressure pressure injection retardant into goaf, and uniformly, retardant dosage is met the requirements, and is not influenced just for retardant sprinkling
Normal coal mining activity, effectively prevent spontaneous combustion of remaining coal, secondly, retardant injection device structure of the present invention is simple, low cost, convenient for peace
Dress, improves coal mining activity working efficiency.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of retardant injection device of the present invention；
Fig. 2 is firing pattern of the invention；
Fig. 3 is that sectional view is arranged in drilling of the invention.
Description of symbols:
1. cabinet, 2. static tubes, 3. distributive pipes, 4. water injection hole packers, 5. grid vertical clapboards, 6. storage bins, 7. baiting valves,
8. pressure gauge, 9. pressure reducing valves, 10. flowmeters, 11. drill sites, 12. drillings, 13. working faces, 14. caving zones, 15. slit bands, 16.
Warp damage, 17. cracks, 18. brackets, 19. cut eye, 20. district sublevel entries.
Specific embodiment
1-3 with reference to the accompanying drawing, specific embodiments of the present invention will be described in detail, it is to be understood that of the invention
Protection scope is not limited by the specific implementation.Based on the embodiments of the present invention, those of ordinary skill in the art are not having
Every other embodiment obtained under the premise of creative work is made, shall fall within the protection scope of the present invention.
Embodiment 1
A kind of new method preventing spontaneous combustion of remaining coal to goaf pressure injection retardant provided by the invention, comprising the following steps:
S1, height investigation is carried out to fissure zone 15 and caving zone 14, the fissure zone 15 that goaf is determined by experiment is emitting
What range of 14 top of band fallen；
S2,11 specification of drill site and spacing, 12 inclination angles of drilling and depth are designed according to the height of fissure zone 15；
S3, retardant injection device is installed after 12 construction of drilling by design and construction drill site 11 and drilling 12；It is such as attached
Shown in Fig. 2, multiple drill sites 11 of constructing in the district sublevel entry of working face 11, each drill site 11 is constructed 5 drillings 12, drills 12
Direction is to cut 20 direction of eye towards working face 11, as shown in figure 3, fissure zone 15 of 12 borehole bottom locations of drilling in above goaf
Interior, drill 12 aperture 90mm；
S4, working face 13 start back production, and after waiting old power stations, the water injection hole packer 4 on retardant injection device is put
Enter in 12 apertures of drilling；
S5, retardant is added to the storage bin 6 of retardant injection device, opens the valve of baiting valve 7 and static tube 2, adjust
Pressure injection flow is saved, after pressure reaches the sealing of hole pressure of water injection hole packer 4, water injection hole packer 4 seals drilling 12, water injection hole packer
4 water outlets automatically open, to goaf pressure injection retardant；
During the pressure injection retardant of goaf, pay attention to observing face roof and the branch for supporting face roof
Uniform water drenching is answered on water outlet status in the water drenching and goaf at 18 rear of frame, face roof top, and when occurring, local water drenching is prominent
When so increasing or being discharged increase suddenly, the valve of static tube 2 is closed immediately, stops pressure injection；To the mistake of goaf pressure injection retardant
Cheng Zhong should also add retardant to storage bin 6；
S6, the back production with working face stop pressure injection after having drilling 12 to penetrate through with caving zone 14, retardant are injected
Device moves on to next drill site 11 and continues pressure injection work.
It should be noted that the common drill site of Specific construction is also in the district sublevel entry construction drill site or high-order drill site of working face
It is that high-order drill site is determined according to 14 height of caving zone and 20 head-room of district sublevel entry.
As shown in Figure 1, the retardant injection device in above-mentioned steps S3 includes: cabinet 1, static tube 2, distributive pipe 3, water filling
Hole packer 4, grid vertical clapboard 5, storage bin 6, baiting valve 7, pressure gauge 8, pressure reducing valve 9 and flowmeter 10, the grid vertical clapboard 5
It is located in cabinet 1, cabinet 1 is divided into left box body and right case by grid vertical clapboard 5, and static tube 2 is connected with left box body, divides water
Pipe 3 is connected with right case, and water injection hole packer 4 is connect with distributive pipe 3 by valve seal, and storage bin 6 is located at the upper of left box body
Side, storage bin 6 are connected by expects pipe with left box body, and baiting valve 7 is located in expects pipe, pressure gauge 8, pressure reducing valve 9 and flowmeter 10
It is each provided on static tube 2.
Working principle is as follows: retardant injecting unit is placed in drill site 11, and retardant injecting unit one end connects static pressure
Distributive pipe 3 is connect by water supply pipe, the other end by valve with water injection hole packer 4, and water injection hole packer 4 is inserted into pressure injection retardant
In drilling 12.When work, the valve on static tube 2 is opened, adjusts pressure and flow, opens baiting valve 7, retardant is from storage bin
6 enter cabinet 1, and retardant aqueous solution is mixed to form with the water entered from static line, and the effect of grid vertical clapboard 5 is to hinder
The retardant for keeping off bulky grain, is allowed to be substantially soluble in water；Enter distributive pipe 3 by the retardant aqueous solution of grid vertical clapboard 5, into
And entering water injection hole packer 4, after the expansion of water injection hole packer 4 reaches certain pressure, the water outlet side valve of water injection hole packer 4 is opened
The retardant aqueous solution for starting, to pouring water into borehole, to inject from drilling 12 is entered in goaf by crack 17.It is every during pressure injection
Every certain time to 6 inhibiting of storage bin, the time interval for adding retardant is related with the flow of water filling.
Water injection hole packer 4 is one kind by dilatable capsule tube after hydraulic pressure effect, and the sebific duct after expansion is expressed to drilling
Wall, sealing drilling prevents the leak outside drilling.Water supply side is accessed in its one end, and the other end is the water outlet side to pouring water into borehole.Work as water
When pressing smaller, only expansion is not discharged, and after expansion reaches certain pressure, water outlet side valve, which is opened, to be started to pouring water into borehole.
To sum up, the present invention utilize working face extraction process generate fissure zone, by district sublevel entry arrange drill site or
High-order drill site, drills into fissure zone, and by retardant injection device, by static pressure, the pressure injection into goaf hinders after drilling and sealing
Agent, uniformly, retardant dosage is met the requirements, and does not influence normal coal mining activity for retardant sprinkling, effectively prevent spontaneous combustion of remaining coal,
Secondly, retardant injection device structure of the present invention is simple, low cost is easily installed, and improves coal mining activity working efficiency.
It although an embodiment of the present invention has been shown and described, for the ordinary skill in the art, can be with
A variety of variations, modification, replacement can be carried out to these embodiments without departing from the principles and spirit of the present invention by understanding
And modification, the scope of the present invention is defined by the appended.
Claims (5)
1. a kind of new method for preventing spontaneous combustion of remaining coal to goaf pressure injection retardant, which comprises the following steps:
S1, height investigation is carried out to fissure zone and caving zone, measures the fissure zone in goaf and the position of caving zone；
S2, drill site specification and spacing, dip angle of hole and depth are designed according to the height of fissure zone；
S3, the multiple drill sites of design and construction are pressed and are drilled, after drilling construction, retardant injection device is installed；
The retardant injection device include: cabinet, static tube, distributive pipe, water injection hole packer, grid vertical clapboard, storage bin, under
Material valve, pressure gauge, pressure reducing valve and flowmeter, the grid vertical clapboard are located in cabinet, and cabinet is divided into a left side by grid vertical clapboard
Cabinet and right case, static tube are connected with left box body, and distributive pipe is connected with right case, and water injection hole packer passes through with distributive pipe
Valve seal connection, storage bin are located at the top of left box body, and storage bin is connected by expects pipe with left box body, and baiting valve is located at material
Guan Shang, pressure gauge, pressure reducing valve and flowmeter are each provided on static tube；
S4, working face start back production, and after waiting old power stations, the water injection hole packer on retardant injection device is put into drilling hole
In mouthful；
S5, retardant is added to the storage bin of retardant injection device, opens the valve of baiting valve and static tube, adjust pressure injection stream
Amount, after pressure reaches the sealing of hole pressure of water injection hole packer, water injection hole packer seals drilling, and hole packer water outlet automatically opens,
To goaf pressure injection retardant；
S6, the back production with working face stop pressure injection after having drilling and caving zone penetrates through, retardant injection device are moved on to
Next drill site continues pressure injection work.
2. a kind of new method for preventing spontaneous combustion of remaining coal to goaf pressure injection retardant as described in claim 1, which is characterized in that
The step S5 is to during the pressure injection retardant of goaf, paying attention to observing face roof and for supporting face roof
Uniform water drenching is answered on water outlet status in the water drenching and goaf at bracket rear, face roof top, and when occurring, local water drenching is prominent
So increase or be discharged the valve for closing static tube when increasing suddenly immediately, stops pressure injection.
3. a kind of new method for preventing spontaneous combustion of remaining coal to goaf pressure injection retardant as described in claim 1, which is characterized in that
The step S5 should add retardant to storage bin to during the pressure injection retardant of goaf.
4. a kind of new method for preventing spontaneous combustion of remaining coal to goaf pressure injection retardant as described in claim 1, which is characterized in that
Each drill site of the multiple drill site constructs 5~7 and drills.
5. a kind of new method for preventing spontaneous combustion of remaining coal to goaf pressure injection retardant as described in claim 1, which is characterized in that
The boring direction is directed toward working face open-off cut eye direction, drills borehole bottom location in the fissure zone of above goaf, boring aperture 75
~94mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810367253.0A CN108301862B (en) | 2018-04-23 | 2018-04-23 | A kind of new method preventing spontaneous combustion of remaining coal to goaf pressure injection retardant |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810367253.0A CN108301862B (en) | 2018-04-23 | 2018-04-23 | A kind of new method preventing spontaneous combustion of remaining coal to goaf pressure injection retardant |
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| Publication Number | Publication Date |
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| CN108301862A CN108301862A (en) | 2018-07-20 |
| CN108301862B true CN108301862B (en) | 2019-07-12 |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108843377B (en) * | 2018-05-24 | 2019-10-29 | 山东科技大学 | A kind of coal seam high pressure hydrothermal solution resistanceization method |
| CN111828081A (en) * | 2019-04-23 | 2020-10-27 | 中国矿业大学(北京) | Method for extracting gas and preventing and extinguishing fire by using composite drill hole |
| CN111779451B (en) * | 2020-07-10 | 2022-04-01 | 淮南矿业(集团)有限责任公司 | Fixed-point water injection drilling method for goaf |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101092879B (en) * | 2007-07-26 | 2010-06-02 | 康怀宇 | Method for injecting retarder to coal body |
| CN102758645A (en) * | 2012-07-24 | 2012-10-31 | 大同煤矿集团有限责任公司 | Fully-mechanized top-coal caving face initial-mining-stage goaf fire prevention and extinguishment method |
| CN203097930U (en) * | 2013-03-16 | 2013-07-31 | 抚顺正工矿业科技发展有限公司 | Efficient gas atomizing inhibition device for coal mine |
| CN104514577B (en) * | 2014-12-12 | 2016-04-20 | 中国矿业大学 | The method of coal seam large area spontaneous combustion in goaf is hidden in a kind of efficient improvement shallow embedding |
| CN107642375A (en) * | 2017-11-08 | 2018-01-30 | 太原理工大学 | A kind of method for preventing the goaf coal spontaneous combustion of mining of closed distance coal seam group levels |
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