CN102777181A - Method for recovering top coals in advance on full-mechanized caving mining face - Google Patents
Method for recovering top coals in advance on full-mechanized caving mining face Download PDFInfo
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- CN102777181A CN102777181A CN2012102802474A CN201210280247A CN102777181A CN 102777181 A CN102777181 A CN 102777181A CN 2012102802474 A CN2012102802474 A CN 2012102802474A CN 201210280247 A CN201210280247 A CN 201210280247A CN 102777181 A CN102777181 A CN 102777181A
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Abstract
The invention relates to the top coal recovering technology, specifically to a method for recovering top coals in advance on a full-mechanized caving mining face. According to the invention, the problem that recovery rate of full-mechanized caved top coals is low is solved. The method for recovering top coals in advance on the full-mechanized caving mining face is realized by using the following steps: step a of arranging an open-off cut on the full-mechanized caving mining face, and then drilling a row of bore holes along an axial line of the open-off cut; step b of backstopping after finishing drilling bore holes; putting explosives into bore holes and detonating after backstopping at 1-2 times, and exploding a main roof with explosives; and step c of continuously backstopping after finishing exploding; and starting recovering top coals after the exploded main roof falls down. The method provided by the invention is capable of effectively solving the problem that recovery rate of full-mechanized caved top coals is low, and is applied to developing for thick seams.
Description
Technical field
The present invention relates to top coal recovery technology, specifically is the method that a kind of fully mechanized coal face reclaims the top coal in advance.
Background technology
At present, big mining and high comprehensive mining and two kinds of methods of longwall top coal caving are mainly adopted in the exploitation of high seam.Wherein, the advantage of big mining and high comprehensive mining is that resource recovery is high, and shortcoming is that the equipment up-front investment is big, and because mining height is big, rib is prone to wall caving takes place, and then possibly cause the roof fall of fully mechanized coal face top board.Compared to big mining and high comprehensive mining, the advantage of longwall top coal caving is that the equipment up-front investment is little, but that its shortcoming is a top-coal recovery rate is low.Particularly, the top coal losses of longwall top coal caving comprise mainly that fully mechanized coal face is just adopted, the top coal losses of Mo Cai and fully mechanized coal face two ends.Wherein, The top coal losses that fully mechanized coal face is just adopted is meant: at the beginning of the fully mechanized coal face back production; If (the top coal has collapsed) just begins to reclaim the top coal before the first weighting of basic top, can cause support not connect the top, pushing and sliding, moving difficulty; Particularly equipment such as support are threatened during first weighting greatlyyer on basic top, and the large tracts of land roof caving very easily causes, and the goaf pernicious gas is extruded suddenly, the fully mechanized coal face gas exceeding limit.Therefore in order to prevent that basic top first weighting from threatening to fully mechanized coal face; Only carry out back production at the beginning of the fully mechanized coal face back production; And do not reclaim the top coal, treat that fully mechanized coal face advances a segment distance (generally behind the first weighting of basic top), just begins normally to reclaim the top coal.Generally; Fully mechanized coal face basically top first weighting step pitch generally (press manifest strong top board reach more than the 50m) about 30-40m; Be that fully mechanized coal face advances 30-40m just to begin to reclaim the top coal later on, cause thus that the top coal losses is big, top-coal recovery rate is low.Be necessary to invent a kind of brand-new top coal recovery method, to solve the low problem of longwall top coal caving top-coal recovery rate for this reason.
Summary of the invention
The present invention provides a kind of fully mechanized coal face to reclaim the method for top coal in advance in order to solve the low problem of longwall top coal caving top-coal recovery rate.
The present invention adopts following technical scheme to realize: a kind of fully mechanized coal face reclaims the method for top coal in advance, and this method is to adopt following steps to realize: a. is drilled with the tier hole along the open-off cut axis direction after fully mechanized coal face open-off cut layout is accomplished; B. after being drilled with the completion of big gun hole, carry out back production; After treating back production 1-2 cutter, the explosive and ignite of in the big gun hole, packing into, by explosive to the explosion of basic jacking row; C. after explosion is accomplished, proceed back production; Treat to be begun to reclaim the top coal by the basic top of the explosion backwardness that collapses.
A kind of fully mechanized coal face of the present invention reclaims the method for top coal in advance through carrying out deep hole blasting before just adopting at fully mechanized coal face; Destroyed the integrality of the basic rimrock layer of open-off cut; Shortened basic top first weighting step pitch (having shortened 1/2-1/3); Realized reclaiming the top coal in advance, improved top-coal recovery rate, and prevented or weakened the hidden danger that the top board large tracts of land is pressed; The method that a kind of fully mechanized coal face of the present invention thus reclaims the top coal in advance efficiently solves the low problem of longwall top coal caving top-coal recovery rate, has realized the safety and high efficiency of high seam.
Through following experiment, can further verify above-mentioned beneficial effect of the present invention: No. 3 coal seams, certain ore deposit, the coal seam average thickness is 5.6m, seam hardness is f=1.2, is flat seam.Directly the top is the chiltern mud stone, and hardness is f=4.2, and average thickness is 2m.Basic top is the canescence medium sandstone, and the sandstone densification is hard, and hardness is f=6.9, and average thickness is 8.0m.The length of fully mechanized coal face open-off cut is 137m, and wide is 7.0m.The coal-winning machine coal cutting highly is 3.0m, and the Caving Coal height is 2.6m.Experimental procedure is following: after the fully mechanized coal face open-off cut is arranged completion, be drilled with the tier hole along the open-off cut axis direction and amount to 19.Distance between the outer group of big gun hole and open-off cut is 0.5m, and the angle in big gun hole is 29-57 °, and the diameter in big gun hole is 75mm, and the tilt length in big gun hole is 15-28m, and the total length in big gun hole is 458.4m.After being drilled with the completion of big gun hole, carry out back production.After treating coal-winning machine coal cutting 2 cuttves, adopt continuously not in the big gun hole, pack into explosive and adopt double detonator and two detonating fuses to ignite of coupled modes.The powder stick specification of explosive is Φ 60 * 400mm, 1.35 ± 0.1kg/ volume.The loaded length in big gun hole is 9.49-16.96m, and the powder charge total length in big gun hole is 280.98m, and the powder charge gross weight in big gun hole is 948.3kg, and the sealing clay length in big gun hole is greater than 25% of big gun hole length.Ignition is in proper order: the air return way along open-off cut is assembled into explosive, gradation ignition to haulage gate direction branch.Explosion is proceeded back production after accomplishing.As shearer gearhead propelling 4m, when tail advanced 6.4m, the top coal all collapsed, and working resistance of support continues to increase.As shearer gearhead propelling 9.2m, when tail advanced 12.0m, working resistance of support reached maximum value.Afterwards, working resistance of support reduces to some extent, in conjunction with on-the-spot macroscopic view observation, is judged to be basic top and has collapsed.Begin to organize Caving Coal this moment, sees the basic rock of canescence.Experimental result shows: after adopting a kind of fully mechanized coal face of the present invention to reclaim the method for top coal in advance, basic top first weighting step pitch has shortened about 15m, reclaims top coal 15m in advance, and top coal yield has increased 6937.2t.
The present invention efficiently solves the low problem of longwall top coal caving top-coal recovery rate, is applicable to the exploitation of high seam.
Description of drawings
Fig. 1 is a method sketch map of the present invention.
Fig. 2 is I-I sectional view of Fig. 1.
Fig. 3 is II-II sectional view of Fig. 1.
Among the figure: the 1-air return way, the 2-haulage gate, the 3-open-off cut, the 4-open-off cut is helped outward, group in the 5-open-off cut, 6-big gun hole, 7-top coal, 8-directly pushes up, and 9-pushes up basically.
The specific embodiment
Embodiment one
A kind of fully mechanized coal face reclaims the method for top coal in advance, and this method is to adopt following steps to realize:
A. after fully mechanized coal face open-off cut 3 is arranged completion, be drilled with tier hole 6 along open-off cut 3 axis directions;
B. after being drilled with the completion of big gun hole, carry out back production; After treating back production 1 cutter, in big gun hole 6, pack into explosive and ignition are carried out explosion by explosive to basic top 9;
C. after explosion is accomplished, proceed back production; Treat to be begun to reclaim top coal 7 by the basic top 9 of the explosion backwardness that collapses;
Among the said step a, the distance between the outer group 4 of big gun hole 6 and open-off cut is 0.3m;
Among the said step a, the angle in big gun hole 6 is 25 °;
Among the said step a, the diameter in big gun hole 6 is 75mm;
Among the said step a, the vertical depth in big gun hole 6 is confirmed through following formula:
In the following formula:
is the vertical depth in big gun hole;
is the thickness of open-off cut top coal;
is the thickness that directly pushes up;
is the thickness on basic top;
Among the said step a, the spacing in big gun hole 6 is confirmed through following formula:
；
More than various in:
is the spacing in big gun hole;
is crack district radius behind the explosive blasting;
is the dynamic compressive strength of single shaft of coal and rock;
is the dynamic tensile strength of single shaft of coal and rock;
is the density of explosive;
is the explosion velocity of explosive; Pressure enhancement coefficient when
expands collision big gun hole wall for the explosive charge product;
is the powder charge coefficient of coup not radially in big gun hole;
is the expansion specific heat ratio of detonation products;
is the powder charge axial factor in big gun hole;
is load propagation attenuation index;
is the lateral stress coefficient;
is the radius in big gun hole;
is the radius of explosive cartridge bag;
is the dynamic poisson's ratio of coal and rock;
Among the said step b, adopt not the coupled modes explosive of in big gun hole 6, packing into; The loaded length in big gun hole is not more than the degree of depth of big gun hole in basic top; The sealing clay length in big gun hole is not less than 25% of big gun hole length; Adopt double detonator and two detonating fuses to ignite; Ignition is in proper order: the air return way 1 along open-off cut 3 is assembled into explosive, gradation ignition to haulage gate 2 direction branches; Explosive adopts emulsion explosive for coal mine.
Embodiment two
A kind of fully mechanized coal face reclaims the method for top coal in advance, and this method is to adopt following steps to realize:
A. after fully mechanized coal face open-off cut 3 is arranged completion, be drilled with tier hole 6 along open-off cut 3 axis directions;
B. after being drilled with the completion of big gun hole, carry out back production; After treating back production 2 cuttves, in big gun hole 6, pack into explosive and ignition are carried out explosion by explosive to basic top 9;
C. after explosion is accomplished, proceed back production; Treat to be begun to reclaim top coal 7 by the basic top 9 of the explosion backwardness that collapses;
Among the said step a, the distance between the outer group 4 of big gun hole 6 and open-off cut is 0.7m;
Among the said step a, the angle in big gun hole 6 is 60 °;
Among the said step a, the diameter in big gun hole 6 is 75mm;
Among the said step a, the vertical depth in big gun hole 6 is confirmed through following formula:
In the following formula:
is the vertical depth in big gun hole;
is the thickness of open-off cut top coal;
is the thickness that directly pushes up;
is the thickness on basic top;
Among the said step a, the spacing in big gun hole 6 is confirmed through following formula:
；
More than various in:
is the spacing in big gun hole;
is crack district radius behind the explosive blasting;
is the dynamic compressive strength of single shaft of coal and rock;
is the dynamic tensile strength of single shaft of coal and rock;
is the density of explosive;
is the explosion velocity of explosive; Pressure enhancement coefficient when
expands collision big gun hole wall for the explosive charge product;
is the powder charge coefficient of coup not radially in big gun hole;
is the expansion specific heat ratio of detonation products;
is the powder charge axial factor in big gun hole;
is load propagation attenuation index;
is the lateral stress coefficient;
is the radius in big gun hole;
is the radius of explosive cartridge bag;
is the dynamic poisson's ratio of coal and rock;
Among the said step b, adopt not the coupled modes explosive of in big gun hole 6, packing into; The loaded length in big gun hole is not more than the degree of depth of big gun hole in basic top; The sealing clay length in big gun hole is not less than 25% of big gun hole length; Adopt double detonator and two detonating fuses to ignite; Ignition is in proper order: the air return way 1 along open-off cut 3 is assembled into explosive, gradation ignition to haulage gate 2 direction branches; Explosive adopts emulsion explosive for coal mine.
Embodiment three
A kind of fully mechanized coal face reclaims the method for top coal in advance, and this method is to adopt following steps to realize:
A. after fully mechanized coal face open-off cut 3 is arranged completion, be drilled with tier hole 6 along open-off cut 3 axis directions;
B. after being drilled with the completion of big gun hole, carry out back production; After treating back production 1 cutter, in big gun hole 6, pack into explosive and ignition are carried out explosion by explosive to basic top 9;
C. after explosion is accomplished, proceed back production; Treat to be begun to reclaim top coal 7 by the basic top 9 of the explosion backwardness that collapses;
Among the said step a, the distance between the outer group 4 of big gun hole 6 and open-off cut is 0.5m;
Among the said step a, the angle in big gun hole 6 is 45 °;
Among the said step a, the diameter in big gun hole 6 is 75mm;
Among the said step a, the vertical depth in big gun hole 6 is confirmed through following formula:
In the following formula:
is the vertical depth in big gun hole;
is the thickness of open-off cut top coal;
is the thickness that directly pushes up;
is the thickness on basic top;
Among the said step a, the spacing in big gun hole 6 is confirmed through following formula:
；
More than various in:
is the spacing in big gun hole;
is crack district radius behind the explosive blasting;
is the dynamic compressive strength of single shaft of coal and rock;
is the dynamic tensile strength of single shaft of coal and rock;
is the density of explosive;
is the explosion velocity of explosive; Pressure enhancement coefficient when
expands collision big gun hole wall for the explosive charge product;
is the powder charge coefficient of coup not radially in big gun hole;
is the expansion specific heat ratio of detonation products;
is the powder charge axial factor in big gun hole;
is load propagation attenuation index;
is the lateral stress coefficient;
is the radius in big gun hole;
is the radius of explosive cartridge bag;
is the dynamic poisson's ratio of coal and rock;
Among the said step b, adopt not the coupled modes explosive of in big gun hole 6, packing into; The loaded length in big gun hole is not more than the degree of depth of big gun hole in basic top; The sealing clay length in big gun hole is not less than 25% of big gun hole length; Adopt double detonator and two detonating fuses to ignite; Ignition is in proper order: the air return way 1 along open-off cut 3 is assembled into explosive, gradation ignition to haulage gate 2 direction branches; Explosive adopts emulsion explosive for coal mine.
Claims (7)
1. a fully mechanized coal face reclaims the method for top coal in advance, it is characterized in that: this method is to adopt following steps to realize:
A. after fully mechanized coal face open-off cut (3) is arranged completion, be drilled with tier hole (6) along open-off cut (3) axis direction;
B. after being drilled with the completion of big gun hole, carry out back production; After treating back production 1-2 cutter, in big gun hole (6), pack into explosive and ignition are carried out explosion by explosive to basic top (9);
C. after explosion is accomplished, proceed back production; Treat to be begun to reclaim top coal (7) by the basic top (9) of the explosion backwardness that collapses.
2. a kind of fully mechanized coal face according to claim 1 reclaims the method for top coal in advance, it is characterized in that: among the said step a, it is 0.3-0.7m that big gun hole (6) and open-off cut are helped the distance between (4) outward.
3. a kind of fully mechanized coal face according to claim 1 reclaims the method for top coal in advance, it is characterized in that: among the said step a, the angle of big gun hole (6) is 25-60 °.
4. a kind of fully mechanized coal face according to claim 1 reclaims the method for top coal in advance, it is characterized in that: among the said step a, the diameter of big gun hole (6) is 75mm.
5. a kind of fully mechanized coal face according to claim 1 reclaims the method for top coal in advance, it is characterized in that: among the said step a, the vertical depth of big gun hole (6) is confirmed through following formula:
In the following formula:
is the vertical depth in big gun hole;
is the thickness of open-off cut top coal;
is the thickness that directly pushes up;
is the thickness on basic top.
6. a kind of fully mechanized coal face according to claim 1 reclaims the method for top coal in advance, it is characterized in that: among the said step a, the spacing of big gun hole (6) is confirmed through following formula:
More than various in:
is the spacing in big gun hole;
is crack district radius behind the explosive blasting;
is the dynamic compressive strength of single shaft of coal and rock;
is the dynamic tensile strength of single shaft of coal and rock;
is the density of explosive;
is the explosion velocity of explosive; Pressure enhancement coefficient when
expands collision big gun hole wall for the explosive charge product;
is the powder charge coefficient of coup not radially in big gun hole;
is the expansion specific heat ratio of detonation products;
is the powder charge axial factor in big gun hole;
is load propagation attenuation index;
is the lateral stress coefficient;
is the radius in big gun hole;
is the radius of explosive cartridge bag;
is the dynamic poisson's ratio of coal and rock.
7. a kind of fully mechanized coal face according to claim 1 reclaims the method for top coal in advance, it is characterized in that: among the said step b, adopt not the coupled modes explosive of in big gun hole (6), packing into; The loaded length in big gun hole is not more than the degree of depth of big gun hole in basic top; The sealing clay length in big gun hole is not less than 25% of big gun hole length; Adopt double detonator and two detonating fuses to ignite; Ignition is in proper order: the air return way (1) along open-off cut (3) is assembled into explosive, gradation ignition to haulage gate (2) direction branch; Explosive adopts emulsion explosive for coal mine.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103244180A (en) * | 2013-04-23 | 2013-08-14 | 山西潞安环保能源开发股份有限公司 | Gob-side entry driving surrounding rock control method using remaining small pillars |
| CN106499394A (en) * | 2016-11-16 | 2017-03-15 | 山东鲁泰控股集团有限公司 | A kind of machine gun is closed adopts the coal winning technology for improving lump coal rate |
| CN108798670A (en) * | 2018-05-30 | 2018-11-13 | 山西西山晋兴能源有限责任公司斜沟煤矿 | A method of it improving super high seam fully mechanized coal face and just adopts coal recovery rate |
| CN110553558A (en) * | 2019-07-21 | 2019-12-10 | 西山煤电(集团)有限责任公司 | Deep hole presplitting blasting method during initial mining and initial setting period of working face of extra-thick coal seam |
| CN111237006A (en) * | 2020-02-17 | 2020-06-05 | 中煤科工集团重庆研究院有限公司 | Method for preventing and controlling rock burst and gas emission in linkage manner of high-length and short-distance drilling |
| CN111964545A (en) * | 2020-07-09 | 2020-11-20 | 安徽理工大学 | Rock roadway deep hole loosening blasting method based on axial multipoint simultaneous detonation |
| CN112179228A (en) * | 2020-09-29 | 2021-01-05 | 太原理工大学 | Deep hole subsection blasting joint cutting control top plate overall collapse method |
| CN113669062A (en) * | 2021-09-27 | 2021-11-19 | 重庆大学 | Fault activation type rock burst control method based on ground pressure-bearing blasting |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103244180A (en) * | 2013-04-23 | 2013-08-14 | 山西潞安环保能源开发股份有限公司 | Gob-side entry driving surrounding rock control method using remaining small pillars |
| CN106499394A (en) * | 2016-11-16 | 2017-03-15 | 山东鲁泰控股集团有限公司 | A kind of machine gun is closed adopts the coal winning technology for improving lump coal rate |
| CN108798670A (en) * | 2018-05-30 | 2018-11-13 | 山西西山晋兴能源有限责任公司斜沟煤矿 | A method of it improving super high seam fully mechanized coal face and just adopts coal recovery rate |
| CN110553558A (en) * | 2019-07-21 | 2019-12-10 | 西山煤电(集团)有限责任公司 | Deep hole presplitting blasting method during initial mining and initial setting period of working face of extra-thick coal seam |
| CN111237006A (en) * | 2020-02-17 | 2020-06-05 | 中煤科工集团重庆研究院有限公司 | Method for preventing and controlling rock burst and gas emission in linkage manner of high-length and short-distance drilling |
| CN111964545A (en) * | 2020-07-09 | 2020-11-20 | 安徽理工大学 | Rock roadway deep hole loosening blasting method based on axial multipoint simultaneous detonation |
| CN112179228A (en) * | 2020-09-29 | 2021-01-05 | 太原理工大学 | Deep hole subsection blasting joint cutting control top plate overall collapse method |
| CN112179228B (en) * | 2020-09-29 | 2022-08-16 | 太原理工大学 | Deep hole subsection blasting joint cutting control top plate overall collapse method |
| CN113669062A (en) * | 2021-09-27 | 2021-11-19 | 重庆大学 | Fault activation type rock burst control method based on ground pressure-bearing blasting |
| CN113669062B (en) * | 2021-09-27 | 2023-11-03 | 重庆大学 | Fault activated rock burst control method based on ground pressure blasting |
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