CN110173294A - coal mine goaf hidden disaster treatment method - Google Patents
coal mine goaf hidden disaster treatment method Download PDFInfo
- Publication number
- CN110173294A CN110173294A CN201910445657.1A CN201910445657A CN110173294A CN 110173294 A CN110173294 A CN 110173294A CN 201910445657 A CN201910445657 A CN 201910445657A CN 110173294 A CN110173294 A CN 110173294A
- Authority
- CN
- China
- Prior art keywords
- cacl
- coal
- coal mine
- goaf
- aqueous solution
- 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.)
- Pending
Links
- 239000003245 coal Substances 0.000 title claims abstract description 65
- 238000000034 method Methods 0.000 title claims abstract description 15
- 239000007789 gas Substances 0.000 claims abstract description 27
- 239000007864 aqueous solution Substances 0.000 claims abstract description 24
- 239000001110 calcium chloride Substances 0.000 claims abstract description 17
- 229910001628 calcium chloride Inorganic materials 0.000 claims abstract description 17
- 239000011261 inert gas Substances 0.000 claims abstract description 15
- 238000007726 management method Methods 0.000 claims description 17
- 238000000889 atomisation Methods 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 238000012546 transfer Methods 0.000 claims description 13
- 239000002245 particle Substances 0.000 claims description 8
- 229910000831 Steel Inorganic materials 0.000 claims description 6
- 239000010959 steel Substances 0.000 claims description 6
- 239000002360 explosive Substances 0.000 claims description 5
- 230000010412 perfusion Effects 0.000 claims description 5
- 239000007921 spray Substances 0.000 claims description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 4
- 239000000243 solution Substances 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 2
- 238000002485 combustion reaction Methods 0.000 abstract description 19
- 230000002269 spontaneous effect Effects 0.000 abstract description 19
- 238000004880 explosion Methods 0.000 abstract description 15
- 238000005065 mining Methods 0.000 abstract description 5
- 238000005507 spraying Methods 0.000 abstract 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 5
- 239000001301 oxygen Substances 0.000 description 5
- 229910052760 oxygen Inorganic materials 0.000 description 5
- 238000009825 accumulation Methods 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 239000011435 rock Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000002265 prevention Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 206010003497 Asphyxia Diseases 0.000 description 1
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- 240000006240 Linum usitatissimum Species 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- 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
- 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
-
- 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
- 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
- E21F5/06—Fluids used for spraying
-
- 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)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
Abstract
The invention relates to a hidden disaster treatment method for a coal mine goaf, and belongs to the field of coal mine fire treatment. The invention adopts spraying CaCl2The method for pouring the inert gas and the aqueous solution are combined with the mode of pouring N in the pre-buried pipeline of the goaf2And atomized CaCl2And (3) selecting the outlet area of the casing pipe and setting the outlets of the inner pipe and the outer pipe to finally enable the conditions in the coal mining area not to meet the conditions of spontaneous combustion of the residual coal and gas explosion. Compared with the control measures of separately considering the spontaneous combustion of the residual coal and the gas explosion in the prior art, the control method can consider the contradiction between the measures of preventing the spontaneous combustion of the residual coal and the gas explosion, and realize that one method simultaneously solves hidden disasters of two goafs.
Description
Technical field
The invention belongs to coal-mine fires to administer field, and in particular to the hidden hazard management method in coal mine gob.
Background technique
The thinking of development of Coal Industrial is mainly " control east, stablize middle part, greatly develop western part ".For western ground
Area, Large-scale Coal construction of base will be carried forward vigorously, and the large-scale In Modern Mine of a collection of ten-million-ton scale is especially focused the consruction on.It is western
Mining area rich coal resources, the easy spontaneous combustion in coal seam bury shallow (buried depth is usually no more than 200 meters), coal seam spacing closely and top plate basement rock
Thin, working face mainly uses mining technology, and since mining influence easily causes a wide range of surface subsidence and crack, earth's surface is easy
The channel of leaking out of a large amount of connection is formed with goaf, so that earth's surface is leaked out seriously, goaf coal spontaneous fire is very frequent；Together
When goaf connection in flakes, area it is big, exacerbate the difficulty of prevention and cure of goaf coal spontaneous combustion, the safety that greatly affected mine is high
Effect exploitation, causes huge economic loss and great social influence.According to incompletely statistics, mine of western occurs nearly ten years
200 times or more the coal spontaneous combustion accidents for causing to close working face, direct economic loss surpass 10,000,000,000 yuan.
Coal mine gob belongs to hidden region, and personnel and equipment all cannot be introduced into the region, due to by coal winning technology, coal
The limitation of the factors such as layer geological conditions, mine ventilation mode causes goaf to there is a large amount of something lost coals, goaf air leaking, gas dense
The easy generations for causing spontaneous combustion in goaf fire and goaf gas explosion accident of unfavorable conditions such as degree transfinites.It loses in goaf
Two kinds of disasters of coal spontaneous combustion and gas explosion are mutually promoted, and coal spontaneous combustion provides incendiary source for gas explosion and causes gas quick-fried
Fried, goaf gas explosion generates a large amount of heat and can ignite Residual coal in goaf, but in both administering methods conflicting, mesh again
Preceding gas govenance mainly increases face air volume and carries out gas drainage under suction in corner or goaf, to improve goaf air leaking
Amount reduces methane accumulation, and the goaf air leaking amount that reduces mainly is taken in coal spontaneous combustion, reduces goaf oxygen concentration, to reach asphyxia
The purpose of coal spontaneous combustion is prevented and treated, two kinds of hidden disasters in goaf are respectively taken at independent method according to intrinsic feature respectively
Reason considers its mutual effect less.
Therefore it is existing there is an urgent need to seek a kind of hidden hazard management method in coal mine gob, can independently to Residual coal in goaf from
Combustion and two kinds of disasters of gas explosion take into account interaction between the two while prevention.
Summary of the invention
In view of this, the purpose of the present invention is to provide the hidden hazard management methods in coal mine gob.
In order to achieve the above objectives, the invention provides the following technical scheme:
The hidden hazard management method in coal mine gob, the described method comprises the following steps:
(1) CaCl is sprayed in goaf2Aqueous solution, the CaCl2Aqueous solution in；
(2) CaCl that will be sprayed in step (1)2Aqueous solution atomization, forms diameter as 1~15 μm of atomization particle water；
(3) perfusion inert gas is conveying power, increases the range of scatter of the atomization particle water.
Preferably, the CaCl sprayed in goaf described in step (1)2Concentration of aqueous solution be not less than 5L/m3。
Preferably, the CaCl2Aqueous solution in CaCl2Mass fraction be 15%~75%.
Preferably, inert gas described in step (3) is nitrogen.
Preferably, the sprinkling CaCl2Aqueous solution and perfusion inert gas pass through in the pre-buried pipeline in the goaf
Mode carries out, and the exit of the pipeline is the space intersectional region for losing coal flammability regime and the explosive region of gas.
Preferably, 8% < O in the something lost coal flammability regime2< 16%, 5% < CH in the explosive region of gas4< 16%.
Preferably, the pipeline is conveyed using sleeve-like manner, and the outer layer of described sleeve pipe isSteel pipe conduct
The internal layer internal layer of the transfer pipeline of inert gas, described sleeve pipe isSteel pipe as CaCl2Aqueous solution delivery pipe
Road.
Preferably, using the floral tube form of tube wall slot within the scope of the end 4m of the transfer pipeline of the inert gas.
Preferably, the CaCl2Aqueous solution transfer pipeline the transfer pipeline away from the inert gas outlet 5m model
Enclose interior setting high-pressure atomization spray head.
The beneficial effects of the present invention are: the present invention provides a kind of hidden hazard management method in coal mine gob, and (1) is being adopted
CaCl is sprayed in mining area2Aqueous solution, moisture film can be formed losing coal surface, reduce contact of the Residual coal in goaf with oxygen and reach
To water conservation moisture-keeping function；(2) aqueous solution of sprinkling is atomized into diameter is 1~15 μm of atomization particle water, can be with adopting
Dead zone is leaked out spreads in entire goaf, increases humidity in goaf, reduces roof caving rock frictional test thermal energy, absorbs and loses coal
The heat generated is aoxidized, destroys oxidization of remained coal accumulation of heat environment, while goaf O can be diluted2And CH4Concentration；(3) indifferent gas is used
Body can increase atomized water in goaf range of scatter, the N injected as conveying power2Goaf can further be diluted
Interior O2And CH4Concentration achievees the purpose that goaf inerting.In addition the present invention is also perfused using by the way of the pre-buried pipeline in goaf
N2With the CaCl of atomization2Aqueous solution, the setting exported by the selection in cannula exit region, inner and outer pipes, final prevention can simultaneously
Make the spontaneous combustion of remaining coal of coal mine gob and the disaster of gas explosion, reaches a kind of mesh of two kinds of hidden disasters in goaf of method solution
's.
Other advantages, target and feature of the invention will be illustrated in the following description to a certain extent, and
And to a certain extent, based on will be apparent to those skilled in the art to investigating hereafter, Huo Zheke
To be instructed from the practice of the present invention.Target of the invention and other advantages can be realized by following specification and
It obtains.
Specific embodiment
Illustrate embodiments of the present invention below by way of specific specific example, those skilled in the art can be by this specification
Other advantages and efficacy of the present invention can be easily understood for disclosed content.The present invention can also pass through in addition different specific realities
The mode of applying is embodied or practiced, the various details in this specification can also based on different viewpoints and application, without departing from
Various modifications or alterations are carried out under spirit of the invention.It should be noted that in the absence of conflict, following embodiment and reality
The feature applied in example can be combined with each other.
Embodiment 1
The necessary and sufficient condition of spontaneous combustion in goaf are as follows: 1. loose coal body；2. sufficient oxygen；3. good regenerative oxidation
Environment.And the necessary and sufficient condition of gas explosion accident occurs for goaf are as follows: 1. certain flach point, and there are the times greater than gas
The sensitive period of explosion；
Incendiary source mainly includes coal spontaneous combustion and roof caving rock frictional test in goaf；2. gas density 5%-16% it
Between.3. oxygen concentration must not be lower than 12%.By reducing O in goaf accumulation of heat environment and inerting goaf2、CH4Concentration is realized
The hidden disaster spontaneous combustion of remaining coal in goaf and gas explosion prevent and treat purpose.
Therefore in order to prevent the spontaneous combustion of remaining coal of coal mine gob and the disaster of gas explosion simultaneously, need to consider simultaneously two kinds of calamities
Harmful necessary condition needs a kind of method that can prevent two kinds of disasters simultaneously.
The hidden hazard management method in coal mine gob:
(1) CaCl that mass fraction is 15%~75% is prepared2Aqueous solution, be sprayed in goaf, make to spray
The concentration in space is not less than 5L/m3, moisture film can be formed on the something lost coal surface in goaf, to reduce the something lost coal in goaf
Contact between oxygen, and at the same time reaching water conservation moisture-keeping function；
(2) make the CaCl being sprayed in goaf using high pressure micropore collision theory2Aqueous solution be atomized, most end form
The atomization particle water for being 1~15 μm at diameter, the atomization particle water of formation can expand in entire goaf with goaf air leaking
It dissipates, to further increase the humidity in goaf, on the one hand reduces and produced between the rock of the roof caving in coal mine gob
On the other hand the heat of oxidization of remained coal generation can be absorbed in raw frictional heat energy, destroy oxidization of remained coal accumulation of heat environment, while can also
Enough dilute the O in goaf2And CH4Concentration；
(3) using perfusion inert gas N2As conveying power, to increase atomization particle water in the expansion of coal mine gob
Range is dissipated, and with inert gas N2Perfusion, can further dilute O in coal mine gob2And CH4Concentration, to reach
To the purpose of goaf inerting.
In order to facilitate the operation and safety, the present invention are irrigated N by the way of pre-buried pipeline2With sprinkling CaCl2's
The egress selection of pipeline is being lost coal flammability regime (8% < O by aqueous solution2< 16%) and the explosive region (5% < CH of gas4< 16%)
Space intersectional region in.In addition pipeline is conveyed by the way of casing, and the steel pipe of outer layer is as N2Transfer pipeline,
InThe floral tube form of tube wall slot is used in line end 4m range, to increase atomized water and N2Go out in goaf
Open area；And the steel pipe of internal layer is CaCl2Aqueous solution transfer pipeline, andIn N2Transfer pipeline exports interior 5m model
Enclose setting high-pressure atomization spray head, inert gas N2Transfer pipeline is located at the outside of casing, on the one hand can be to CaCl2Aqueous solution
Transfer pipeline plays a protective role, and on the other hand can high-pressure atomization spray head be cleaned and be replaced at any time, reduces over long distances
Convey the condensation number of atomized water.
With in the prior art individually consider spontaneous combustion of remaining coal compared with gas explosion control measure, administering method energy of the invention
The paradox considered between spontaneous combustion of remaining coal and gas explosion control measure is enough taken into account, realizes that a kind of method two kinds of solution simultaneously is mined out
The hidden disaster in area, and the hazard management material source of administering method selection of the invention is extensive, cheap, and the side of operation
Just, regulation effect is good.
Finally, it is stated that the above examples are only used to illustrate the technical scheme of the present invention and are not limiting, although referring to compared with
Good embodiment describes the invention in detail, those skilled in the art should understand that, it can be to skill of the invention
Art scheme is modified or replaced equivalently, and without departing from the objective and range of the technical program, should all be covered in the present invention
Scope of the claims in.
Claims (9)
1. the hidden hazard management method in coal mine gob, which is characterized in that the described method comprises the following steps:
(1) CaCl is sprayed in goaf2Aqueous solution, the CaCl2Aqueous solution in；
(2) CaCl that will be sprayed in step (1)2Aqueous solution atomization, forms diameter as 1~15 μm of atomization particle water；
(3) perfusion inert gas is conveying power, increases the range of scatter of the atomization particle water.
2. the hidden hazard management method in coal mine gob according to claim 1, which is characterized in that step is adopted described in (1)
The CaCl sprayed in dead zone2Concentration of aqueous solution be not less than 5L/m3。
3. the hidden hazard management method in coal mine gob according to claim 2, which is characterized in that the CaCl2Aqueous solution
Middle CaCl2Mass fraction be 15%~75%.
4. the hidden hazard management method in coal mine gob according to claim 1, which is characterized in that lazy described in step (3)
Property gas be nitrogen.
5. the hidden hazard management method in coal mine gob according to claim 1, which is characterized in that the sprinkling CaCl2Water
Solution and perfusion inert gas are carried out by way of the pre-buried pipeline in the goaf, and the exit of the pipeline is that something lost coal is easy
Fire the space intersectional region in region and the explosive region of gas.
6. the hidden hazard management method in coal mine gob according to claim 5, which is characterized in that the something lost coal flammability regime
In 8% < O2< 16%, 5% < CH in the explosive region of gas4< 16%.
7. the hidden hazard management method in coal mine gob according to claim 5, which is characterized in that the pipeline uses casing
Mode is conveyed, and the outer layer of described sleeve pipe is transfer pipeline of the steel pipe of ￠=80mm as inert gas, described sleeve pipe
Internal layer internal layer is the steel pipe of ￠=10mm as CaCl2Aqueous solution transfer pipeline.
8. the hidden hazard management method in coal mine gob according to claim 7, which is characterized in that the inert gas it is defeated
Send the floral tube form within the scope of the end 4m of pipeline using tube wall slot.
9. the hidden hazard management method in coal mine gob according to claim 7, which is characterized in that the CaCl2Aqueous solution
High-pressure atomization spray head is arranged in transfer pipeline within the scope of the outlet 5m of the transfer pipeline away from the inert gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910445657.1A CN110173294A (en) | 2019-05-27 | 2019-05-27 | coal mine goaf hidden disaster treatment method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910445657.1A CN110173294A (en) | 2019-05-27 | 2019-05-27 | coal mine goaf hidden disaster treatment method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110173294A true CN110173294A (en) | 2019-08-27 |
Family
ID=67695931
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910445657.1A Pending CN110173294A (en) | 2019-05-27 | 2019-05-27 | coal mine goaf hidden disaster treatment method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110173294A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101766877A (en) * | 2010-02-05 | 2010-07-07 | 北京科技大学 | Inorganic salt type inhibitor for preventing and controlling spontaneous combustion of residual coal in goaf of coal mine |
| CN104329109A (en) * | 2014-08-29 | 2015-02-04 | 辽宁工程技术大学 | Gob retardant efficient spraying system and spraying method |
| CN107060870A (en) * | 2017-04-24 | 2017-08-18 | 辽宁工程技术大学 | A kind of goaf retardant efficiently sprays scheme |
| CN107083987A (en) * | 2017-03-24 | 2017-08-22 | 中国矿业大学(北京) | Prevent and treat the nitrogen resistanceization steam fog preparation method and system of underground goaf spontaneous combustionof coal |
| CN109578056A (en) * | 2018-11-25 | 2019-04-05 | 大同煤矿集团有限责任公司 | A kind of administering method about coal mine gob |
-
2019
- 2019-05-27 CN CN201910445657.1A patent/CN110173294A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101766877A (en) * | 2010-02-05 | 2010-07-07 | 北京科技大学 | Inorganic salt type inhibitor for preventing and controlling spontaneous combustion of residual coal in goaf of coal mine |
| CN104329109A (en) * | 2014-08-29 | 2015-02-04 | 辽宁工程技术大学 | Gob retardant efficient spraying system and spraying method |
| CN107083987A (en) * | 2017-03-24 | 2017-08-22 | 中国矿业大学(北京) | Prevent and treat the nitrogen resistanceization steam fog preparation method and system of underground goaf spontaneous combustionof coal |
| CN107060870A (en) * | 2017-04-24 | 2017-08-18 | 辽宁工程技术大学 | A kind of goaf retardant efficiently sprays scheme |
| CN109578056A (en) * | 2018-11-25 | 2019-04-05 | 大同煤矿集团有限责任公司 | A kind of administering method about coal mine gob |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104514577B (en) | The method of coal seam large area spontaneous combustion in goaf is hidden in a kind of efficient improvement shallow embedding | |
| Liu et al. | Early extinguishment of spontaneous combustion of coal underground by using dry-ice’s rapid sublimation: A case study of application | |
| CN102828767A (en) | Gob natural fire control method | |
| CN109236350B (en) | Fire disaster treatment method for large dip angle super-thick coal seam | |
| CN106014480B (en) | A kind of Single thick coal seam Gas Full-Mechanized Caving Face cooperates with administering method with coal spontaneous combustion | |
| CN101993574B (en) | Fireproof high-molecular compound colloid material for coal mines | |
| CN109578056B (en) | Treatment method for coal mine goaf | |
| CN110735660A (en) | device for preventing spontaneous combustion of goaf in coal mine and using method thereof | |
| CN112943343B (en) | Efficient and rapid fire extinguishing method for ground drilling of different types of fires in coal mine goaf | |
| CN102758645A (en) | Fully-mechanized top-coal caving face initial-mining-stage goaf fire prevention and extinguishment method | |
| CN102500077A (en) | Waste dump extinguishing method | |
| CN105041374A (en) | Method for preventing and controlling gas and coal fire together in high-gas close-distance coal seam goaf | |
| CN108843373A (en) | Ultra tiny retardant water mist prevents and treats spontaneous combustion in goaf method | |
| CN211008732U (en) | Device for preventing spontaneous combustion of goaf in coal mine | |
| CN110685728A (en) | Coal seam goaf gas and coal spontaneous combustion cooperative control method | |
| CN110792469A (en) | Inclined coal seam overlength stope face gas and coal spontaneous combustion cooperative treatment method | |
| CN102587883B (en) | Method for quenching underground coal gasifier | |
| Liu et al. | Efficient prevention of coal spontaneous combustion using cooling nitrogen injection in a longwall gob: An application case | |
| CN110173294A (en) | coal mine goaf hidden disaster treatment method | |
| CN108301862B (en) | A kind of new method preventing spontaneous combustion of remaining coal to goaf pressure injection retardant | |
| CN114508380A (en) | Method for treating spontaneous combustion of coal by dividing coal field fire area through gridding method and establishing curtain wall | |
| CN106499431A (en) | Adjacent nitrogen injection in goaf method of fire protection during gob side entry driving | |
| CN107060870A (en) | A kind of goaf retardant efficiently sprays scheme | |
| CN106609677A (en) | A gas extraction and discharge construction method | |
| CN205685866U (en) | A kind of environment-friendly type fire-proof plate for tunnel |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20190827 |
|
| RJ01 | Rejection of invention patent application after publication |