CN106815423A - A kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method - Google Patents
A kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method Download PDFInfo
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- CN106815423A CN106815423A CN201710018845.7A CN201710018845A CN106815423A CN 106815423 A CN106815423 A CN 106815423A CN 201710018845 A CN201710018845 A CN 201710018845A CN 106815423 A CN106815423 A CN 106815423A
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Abstract
The invention discloses a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method, it is characterised in that erecting dense individual props are non-equally distributed, and the broken swollen coefficient of inbreak and porosity distribution are set up by " O-ring " distributed model, it is considered to gravity factor；The keto consumpting speed that oxygen consumption experiment obtains coal is closed according to coal sample, the setting of the non-homogeneous oxygen consumption source item of coal is realized with this.
Description
Technical field
The present invention relates to mining safety, more particularly to coal mine roadway spontaneous combustion of remaining coal simulation.
Background technology
Under the conditions of at this stage, as colliery increases mining depth, substantial amounts of highly gassy mine occurs, and Gas Disaster preventing and treating is appointed
Business is also more severe.In the case of the original Gas Disaster in colliery and heterogeneous goaf disaster, Residual coal in goaf is occurred in that again
Spontaneous combustion hazard zone disaster coexist with interactional new situation, the integrated control of the two be even more emphasis in shaft production and
Difficult point.There are two main mining coal seams in Shanxi Shouyang Duan Wang collieries：9# and 15#, is judged as high gas layer, mine ventilation mode
It is subregion pull-out type.After 2007, the ore deposit progresses into deep mining, due under conventional u-shaped draft type, upper corner watt
This overrun issues often occurs, and mine safety production is subject to significant threat, and capacity production cannot also be ensured.Accordingly, it would be desirable to
Gas pumping is carried out to the ore deposit.Gas pumping is carried out then must
Influence of the gas pumping to spontaneous combustion in goaf must be considered.Using CFD numerical simulation technologies, by change watt
The size of this extraction flow, the influence with reference to actual field data analysis gas pumping intensity to spontaneous combustion in goaf, and it is right
Than real data, more intuitively impact analysis is provided, for gas pumping is optimized under meeting actual actual mining demand condition
And the offer foundation of exploiting field fire extinguishing.
The content of the invention
1. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method, it is characterised in that erecting dense individual props are non-uniform Distributions
, the broken swollen coefficient of inbreak and porosity distribution are set up by " O-ring " distributed model, it is considered to gravity factor；Closed according to coal sample and consumed
Oxygen experiment obtains the keto consumpting speed of coal, and the setting of the non-homogeneous oxygen consumption source item of coal is realized with this.
2. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that work
Face ventilation arrangement be：It is upper along being track lane, lower along being belt lane, return airway is arranged therebetween, away from track lane 30m
Place, forms special " inclined W types, two enter one time " draft type.
3. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that consider
To the actual conditions of working face, in terms of gas preventing and control, this coal seam is mainly taken to arrange drilling and high-order drill site synthesis extraction；This
Coal seam arrangement drilling is to carry out pre-mining drainage, in the rimala band that the boring point of high-order drill site will be more than caving zone.
4. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that for
The maximum height of caving zone, fissure zone after working face extraction, can calculate by following empirical equation, calculate caving zone maximum
The empirical equation of height is：
In formula, H1- caving zone maximum height；M-working face mining height.
5. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that calculate
The empirical equation of fissure zone maximum height is：
In formula, H2- fissure zone maximum height；M-working face mining height.
6. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that modeling
When, two faces between working face and goaf are set to interface (interface), goaf float coal area and caving rock area
Between face, be set to inside face (interior)；The face that tunnel and working face coincide is set to interface；
It is fluid mass (fluid) that Gambit gives tacit consent to whole threedimensional model, and the body of corresponding region is set into belt lane, track respectively
Lane, return airway, working face, float coal and rock.
Brief description of the drawings
The roadway workfaces of Fig. 1 150405 and the arrangement in goaf
Fig. 2 High Position Drillings orientation schematic diagram
Fig. 3 goafs consider angle of inclination model
The face pressures of Fig. 4 150405 and VELOCITY DISTRIBUTION (a) pressure-plotting (b) velocity contour
The work face goaf bound polyamine data of Fig. 5 150405
Fig. 6 stopes gas and oxygen concentration distribution (a) stope gas density distribution (b) stope oxygen concentration distribution
The gas concentration actual measurement of Fig. 7 goafs and the actual measurement of analog result comparison diagram (a) gas density and analog result comparison diagram
B () oxygen concentration is surveyed and analog result comparison diagram
Fig. 8 goaf gas concentration distribution comparison diagrams
Fig. 9 goafs oxygen concentration profiles versus' figure
Figure 10 gas pumpings correspondence oxygen concentration distribution relation figure
Specific embodiment
1 section of working face entirety of king's ore deposit 150405 and gas pumping are arranged
Section king's ore deposit related data shows that the working face of ore deposit 150405 is adopted using Single thick coal seam full-seam mining, retrusive
Coal, working face inclination angle is minimum 2 °, maximum 11 °, average 6.5 °, and it moves towards 809m long, is inclined to 160m long；Coal seam thickness is minimum
4.1m, is 4.35m, average thickness 4.2m, actual recoverable reserves 659686t to the maximum.Face-airing arrangement is：It is above suitable to be
Track lane, it is lower along being belt lane, return airway arrange therebetween, away from the 30m of track lane at, formation is special, and " inclined W types, two enter
One time " draft type.Roadway workface arrangement is as shown in Figure 1.
For the fully-mechanized mining working of section king ore deposit 150405, its belt roadway design is flat away from being 1040m, and net section is designed as
15.75m2；The design of track lane is flat away from being 1045m, and net section is designed as 15.75m2；Return airway design is flat away from being 1063m, net section
It is designed as 15.75m2；Eye 160m long is cut, net section is designed as 25.2m2.Main air intake lane is made in lower belt lane, and track lane aids in
Air intake lane, both air flow rate proportionings press 2：1.According to actual calculating, the air quantity in belt lane takes 1968m3/ min, the air quantity in track lane
Take 984m3/ min, can so meet 150405 working face demands.
Section king's ore deposit field data shows that, in 150405 working face extraction, gas emission is in advance in respect of 36.9m3/min.Examine
Consider the actual conditions of working face, in terms of gas preventing and control, mainly take this coal seam to arrange drilling and high-order drill site synthesis extraction.
The arrangement drilling of this coal seam is to carry out pre-mining drainage, in the rimala band that the boring point of high-order drill site will be more than caving zone.It is known
150405 working face full-seam minings, coal seam average thickness 4.2m.For the maximum height of caving zone, fissure zone after working face extraction
Degree, can calculate by following empirical equation.
Calculate caving zone maximum height empirical equation be：
In formula, H1- caving zone maximum height；M-working face mining height.Then caving zone high computational is obtained：
Calculate fissure zone maximum height empirical equation be：
In formula, H2- fissure zone maximum height；M-working face mining height.Then fissure zone high computational is obtained：
Calculated according to more than and understood, the scope of roof fracture band is between 10.8~40.7m.But, there is one in fissure zone
The rock stratum of height is determined, because larger close to caving zone voidage, then flow through this region gas and be more easy to pour in because suffered resistance is small
Goaf, so band drilling-draining rate is low, we term it big Fractured zone, height about 4m.Therefore, the efficient extraction area of fissure zone
This 4m should be subtracted, final range between 14.8~40.7m, in combination with section king's ore deposit regional geology feature, it is determined that optimal end hole
Position is between more than roof 35~40m.As shown in Figure 2：
2 sections of stope models of king's ore deposit 150405 are set up and parameter setting
According to the measured data of the work face goaf of section king colliery 150405, the three-dimensional physical model after foundation is simplified, such as
Shown in Fig. 3.With working face and goaf round floor intersection point as origin, level is to the right X-axis to the model, and level is upwards Y-axis, is erected
Straight is upwards Z axis, sets up reference frame, and the seam inclination that model is set up is 6 °, and return airway side is higher than belt lane side, the model
The basic parameter of foundation is as shown in table 1.
The mined out section model basic parameter of table 1
During modeling, two faces between working face and goaf are set to interface (interface), goaf float coal area
And the face between caving rock area, it is set to inside face (interior)；The face that tunnel and working face coincide is set to
interface；It is fluid mass (fluid) that Gambit gives tacit consent to whole threedimensional model, and the body of corresponding region is set into skin respectively
Band lane, track lane, return airway, working face, float coal and rock.
The different buoyancy lifts shown to embody the different gravity of each gas component in goaf, set gravity and accelerate
Straight down, size is 9.81m/s to degree g2.Because the work face goaf of section king colliery 150405 has gas emission greatly and loses
The problem of coal consumption oxygen, makees source item treatment to this two in simulation.
It is as follows to the setting of boundary condition before simulation：150405 working face belt lane imports are set to speed entrance
(velocity-inlet), size is 2.0832m/s, and intake is 1894m3/min；The import of track lane is set to speed entrance
(velocity-inlet), size is 1.041666m/s, and intake is 963m3/min；Return airway outlet is defined as flowexit
(outflow)；To make gas pumping mouthful data consistent with actual extraction result, to study goaf internal gas change rule
Rule, therefore the extraction mouthful in goaf high position gas pumping tunnel is set to speed entrance, velocity magnitude is 0.0854m/s, is taken out
The amount of adopting is set to 82m3/ min, extraction concentration is 25%.
The influence that the change of 3 extraction intensity is aoxidized to coal spontaneous combustion
Simulation under 3.1 physical conditions is contrasted with measured result
The following is the actual extraction amount of the face goaf that worked based on section king colliery 150405, the goaf that analogue simulation is obtained
Fluid field pressure of leaking out distribution map, wind speed profile figure, O2Concentration profile and gas density distribution map, simulation is entered with measured result
Find that both substantially conform to data after row contrast.
By Fig. 4 (a) flow field in goaf static pressure distribution Tu Ke get, working face lower end to pressure difference between return airway is about 140Pa,
It is close with field measurement working face actual measurement pressure difference 150Pa.From Fig. 4 (b) wind speed profile figures, the minimum wind speed of working face is about
1.48m/s, the air quantity about 224m in goaf is leak into from working face3/ min, air leak rate of air curtain is 11.2%, meets 10%-15%'s
The general Air-Leakage Law in goaf.Analysis understands based on more than, the leakage of the pressure difference and working face at the air entering and returning two ends that simulation draws
Air quantity is substantially conformed to the result of actual measurement.
In order to more accurately grasp goaf gas distribution, beam has been carried out respectively along track lane and belt lane at the scene
Pipe monitors the installation of pipeline and data monitoring collection instrument, to the O in goaf2, CH4Collection is monitored with temperature, after collection
Measured data it is as shown in Figure 5.Meanwhile, in order to confirm the accurate reliability of analog result, with reference to section king ore deposit scene physical condition
(gas pumping intensity is 82m3/ min), goaf gas and oxygen concentration distribution are simulated using Fluent, Liang Zhemo
Intend result as shown in Figure 6.Then, gas is contrasted with the analog result of oxygen with the data of actual measurement, both contrast numbers
According to as shown in Figure 7.
In Fig. 6 (a), at upper rail lane side about 30m, gas density is about 3%, as monitoring point turns to goaf deep
Move, gas density can increase accordingly, and 30% or so is increased at 100m；At the about 100m of lower belt lane side, gas density
About 0.3%.After field measurement Data Comparison analog result, it is found that both coincide substantially, such as Fig. 7 (a).It is mined out in Fig. 6 (b)
Oxygen concentration (8%-21%) is distributed as in area：At the about 30m of track lane side, O2Concentration is about 17%, and with going deep into goaf
Gradually increase, to 100m at O2Concentration is about 2.5%；At the about 100m of belt lane side, O2Concentration is about 17%.Analog result is basic
Meet field measurement data, such as Fig. 7 (b).
The influence that 3.2 gas pumping intensity are distributed to oxygen concentration
Under different gas pumping intensity, goaf gas and O2Concentration distribution can change, therefore gas pumping certainty
Influence is produced on spontaneous combustion in goaf.To study its Changing Pattern, the extraction strength condition (60m different to four kinds3/min、
82m3/ min (actual extraction intensity), 100m3/min、120m3/ min) it is simulated respectively and analyzes.
Simulation shows that working face wind speed and two ends blast under four kinds of extraction intensity are basically identical：Belt lane and return airway it
Between pressure difference be about 140Pa；Wind speed is averagely about 1.47m/s, and the minimum air quantity of stope is about 1764m3/ min, goaf
Leak into air quantity about 236m3/ min, air leak rate of air curtain is about 11.8%, meets the general Air-Leakage Law in goaf for 10%-15%.This says
Bright, wind speed and blast because of extraction intensity almost without changing, and influence of the extraction intensity to them is negligible.And it is different
Under extraction strength condition, goaf gas and O2Concentration distribution has big change, and its comparative analysis is as follows.
As gas density profiles versus understand in Fig. 8, increase gas pumping intensity, return airway away between track lane working face and
Gas density is gradually reduced in return airway.When gas pumping intensity is respectively 60m3/min、82m3/min、100m3/min、
120m3During/min, return airway average gas density of working face away between track lane is respectively 0.036,0.0036,0.0023,
0.002, the average gas density of return airway is respectively 0.02,0.003,0.003,0.002；Gas scope in the side goaf of track lane
Reduce as extraction intensity increases, belt lane side gas scope increases therewith.
As goaf oxygen concentration profiles versus can be seen that as gas pumping intensity is changed from small to big in Fig. 9, track lane
Oxygen level increases with the powerful increase of extraction in the goaf of side, and belt lane side oxygen level reduces therewith, oxygen concentration point
Cloth integrally presents trapezoidal.When gas pumping intensity is respectively 60m3/min、82m3/min、100m3/min、120m3During/min, adopt
8% oxygen concentration distribution of dead zone inner orbit lane side respectively reaches 80m, 120m, 100m, 110m, corresponding spontaneous combustion oxidation
Bandwidth is respectively 55m, 95m, 75m, 85m；And 8% oxygen concentration distribution of goaf inner belt lane side is respectively reached
180m, 170m, 170m, 130m, corresponding oxidation bandwidth respectively reach 155m, 145m, 145m, 105m.Here, gas is taken out
Adopt intensity as shown in Figure 9 with the relation of corresponding spontaneous combustion oxidation bandwidth.Oxygen concentration band on a large scale as occurring, gas is one
Aspect factor, at the same also should with lose that coal is relatively thin, oxygen consumption effect is not substantially relevant.
Claims (6)
1. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method, it is characterised in that erecting dense individual props be it is non-equally distributed,
The broken swollen coefficient of inbreak and porosity distribution are set up by " O-ring " distributed model, it is considered to gravity factor；Oxygen consumption reality is closed according to coal sample
The keto consumpting speed for obtaining coal is tested, the setting of the non-homogeneous oxygen consumption source item of coal is realized with this.
2. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that working face leads to
Wind arrangement is：It is upper along being track lane, it is lower along being belt lane, return airway arrange therebetween, at the 30m of track lane, shape
Into special " inclined W types, two enter one time " draft type.
3. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that in view of work
Make the actual conditions in face, in terms of gas preventing and control, mainly take this coal seam to arrange drilling and high-order drill site synthesis extraction；This coal seam
Arrangement drilling is to carry out pre-mining drainage, in the rimala band that the boring point of high-order drill site will be more than caving zone.
4. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that for work
The maximum height of caving zone, fissure zone after the back production of face, can calculate by following empirical equation,
Calculate caving zone maximum height empirical equation be：
In formula, H1- caving zone maximum height；M-working face mining height.
5. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that calculate crack
Empirical equation with maximum height is：
In formula, H2- fissure zone maximum height；M-working face mining height.
6. a kind of W types ventilation goaf spontaneous combustion of remaining coal analogy method according to claim 1, it is characterised in that during modeling, work
Make two faces between face and goaf, interface (interface) is set to, between goaf float coal area and caving rock area
Face, is set to inside face (interior)；The face that tunnel and working face coincide is set to interface；Gambit gives tacit consent to
Whole threedimensional model is fluid mass (fluid), and the body of corresponding region is set into belt lane, track lane, return airway, work respectively
Make face, float coal and rock.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108982587A (en) * | 2018-08-13 | 2018-12-11 | 辽宁工程技术大学 | A kind of coal seam group multilayer goaf solid spontaneous fine seam determination method |
| CN110792469A (en) * | 2019-11-22 | 2020-02-14 | 安徽理工大学 | Inclined coal seam overlength stope face gas and coal spontaneous combustion cooperative treatment method |
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| CN108982587A (en) * | 2018-08-13 | 2018-12-11 | 辽宁工程技术大学 | A kind of coal seam group multilayer goaf solid spontaneous fine seam determination method |
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