CN101858216A - Method for recovering stagnant coal pillars left by breast type coal mining method - Google Patents
Method for recovering stagnant coal pillars left by breast type coal mining method Download PDFInfo
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- CN101858216A CN101858216A CN 201010161124 CN201010161124A CN101858216A CN 101858216 A CN101858216 A CN 101858216A CN 201010161124 CN201010161124 CN 201010161124 CN 201010161124 A CN201010161124 A CN 201010161124A CN 101858216 A CN101858216 A CN 101858216A
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- 239000003245 coal Substances 0.000 title claims abstract description 105
- 238000005065 mining Methods 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 21
- 210000000481 breast Anatomy 0.000 title abstract 3
- 238000004519 manufacturing process Methods 0.000 claims description 29
- 238000011084 recovery Methods 0.000 claims description 24
- 230000002269 spontaneous effect Effects 0.000 abstract description 4
- 239000002390 adhesive tape Substances 0.000 abstract description 3
- 238000007790 scraping Methods 0.000 abstract 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract 1
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 238000004873 anchoring Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- TVEXGJYMHHTVKP-UHFFFAOYSA-N 6-oxabicyclo[3.2.1]oct-3-en-7-one Chemical compound C1C2C(=O)OC1C=CC2 TVEXGJYMHHTVKP-UHFFFAOYSA-N 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011449 brick Substances 0.000 description 1
- 210000000078 claw Anatomy 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000013872 defecation Effects 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
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Abstract
The invention provides a method for recovering stagnant coal pillars left by a breast type coal mining method, which is used for a low-gas shallow coal seam with stable top board, smaller mine pressure and coal seam inclination angle, flat baseboard, hard and stable coal quality, no-water pouring top board and hard spontaneous ignition. The coal pillars are recovered with different regions, every three rows of the coal pillars is taken as a distribution unit, and air curtains are arranged between the three rows of the coal pillars and the coal pillars to form into an air inlet passageway and an air retuning passageway; and from the two rows of regular coal pillars beside a goaf, every two rows of regular coal pillars is taken as a recovering unit, the recovering unit is internally provided with a crawler belt walking type hydraulic bracket, a continuous coal mining device and an advanced supporting hydraulic bracket, the stagnant coal pillars are alternately and slantwise cut by means of both wings according to the recovering unit, the recovering unit stopes and withdraws, the stagnant coal pillars and the hydraulic bracket jointly support the top board above a recovering space, and the top board is managed by means of a complete top board falling method. Therefore, by matching with the continuous coal mining device, the scraping board conveying device and the adhesive tape conveying device, the method can recover the regular stagnant coal pillars left by a breast type coal mining method.
Description
Technical field
The present invention relates to the dull pillar recovery method that a kind of room mining is left over, be particularly useful for that stable roof, mine pressure are less, seam inclination below 10 °, more smooth, the ature of coal hard and steady of base plate, top board do not have trickle and be difficult for the present low gas shallow buried coal seam of spontaneous fire.
Background technology
The essence of barrier system coal-mining method is the bordroom of a series of wide 5～8m of being of digging in the coal seam, links to each other with connection roadway between bordroom, forms to be similar to strip or block coal column, and coal pillar width does not wait by several meters to more than 20 meters.Coal mining is carried out in bordroom.Coal column can stay according to condition and not adopt, or after bordroom has been adopted, again with coal column extraction as far as possible on request.Stay the mode that coal column do not adopt and be called room mining, the method for not only the mined room but also the post of mining is called post and stall.
A lot of coal production bases, area, the Inner Mongol utilize the room mining system, the room of only mining, the post of not mining more.Utilize the coal column roof supporting, bordroom does not adopt any artificial supporting.About 66～7,000,000,000 t coal resources are abandoned in the down-hole, form dull coal amount.Dull coal amount is easy to spontaneous combustion in the process of down-hole long oxidation, and causes environment pollution, causes significant wastage for simultaneously the national precious resource.A few years ago because Coal Economy is depressed, if reclaim coal column, then to buy support and other equipment comes supporting roof, this has just strengthened cost, even unable to make ends meet.Therefore, a lot of coal production bases utilize the room mining system more, the room of only mining, and the post of not mining, resource recovery only accounts for 36%～40%, forms a large amount of dull coal amounts.Therefore the recovery of coal column is present urgent problem.
The Pillar Recovery technology of room and pillar mining system relates to the complication system engineering of numerous related disciplines such as mine pressure and CONTROL OF STRATA MOVEMENT, coal-mining method, ventilation, transportation.Under the cooperation of continuous miner, hydraulic support and complete bolt support equipment, the local success that obtains Pillar Recovery, but in the Pillar Recovery process, substantially all adopt single section way of recycling.Promptly before Pillar Recovery the exploiting field is divided into some sections, recovery is to have adopted the coal column that the bordroom of a section then reclaims this section earlier in proper order.Will lay down the mine pressure of this section like this, adopt adjacent section again, what be subjected to like this that the effect of exploiting field section mine pressure will be little is many.And for the engineering practice research of the Pillar Recovery of full open type (back production intact whole bordrooms reclaim coal column again) seldom, in this respect practice and theoretical research are few.
Summary of the invention
Technical problem: the purpose of this invention is to provide the dull pillar recovery method that a kind of room mining is left over, solve the recovery problem that adopts the dull coal column of leaving over after the room mining exploitation, improve the rate of recovery of coal resources.
Technical scheme: the dull pillar recovery method that room mining of the present invention is left over, step is as follows:
Reclaim a, subregion, and the regular coal column of per three rows is an arrangement unit, from the regular coal column near goaf one side, between three regular coal columns of row and coal column air curtain is set, and makes the regular coal column of three rows form air intake passage and return air channel;
B, near goaf side two row regular coal column, per two row regular coal column be a back production unit, each back production unit carries out back production by the border to the main haulage roadway direction;
C, caterpillar track travelling hydraulic supports and continuous miner are laid in two coal column positions of first trip of air intake passage in the back production unit, and wait the to mine side of post of 2～3 row behind the first trip coal column is provided with a plurality of forepoling hydraulic supports, then at the continuous miner rear drag conveyor and rubber conveyer is set;
D, two coal columns about first trip are alternately implemented the feed of double-vane inclined cutout, Bian Caibian retreats, and by the drag conveyor that is located at the continuous miner rear coal is sent into rubber conveyer in the coal mining process coal is transported;
E, continuous miner are after two coal columns have respectively advanced a cutter about to first trip, and the caterpillar track travelling hydraulic support at its rear portion in time step pitch of reach carries out supporting;
F, reclaimed two coal columns of first trip after, forepoling hydraulic support is moved forward, per two one group of forepoling hydraulic support, strong point reach each other, caterpillar track travelling hydraulic support and continuous miner move forward thereupon, continue the back production of two coal columns of next line, repeating step d and step e are until finishing a back production unit;
G, repeat above-mentioned institute in steps, until the recovery of finishing all dull coal columns of leaving over.
Beneficial effect: the present invention utilizes forepoling hydraulic support, caterpillar track travelling hydraulic support and coal column roof supporting, under caterpillar track travelling hydraulic support supports, to the dull coal column left over by the back production of back production unit, the limit of mining inside ceiling panel is within the limit span, safer reliable to dull Pillar Recovery.The advance support distance of forepoling hydraulic support reaches 24m, use is closed in per two one assembly, strong point reach each other, satisfy the advance support distance of about 20m under the normal condition, leading area of stress influence to side in face of the back production has been carried out supporting, has effectively guaranteed the stability of work plane the place ahead bordroom with the dull coal column of leaving over.There is good adaptive capacity in coal seam for the ature of coal hard and steady, is particularly useful for the present low gas coal seam that mine pressure is little, spontaneous fire is stablized and be difficult for to roof and floor.Can when highly effective and safe is produced, realize the recovery of dull coal resources, improve the rate of recovery of coal resources.Adopt continuous miner, crab claw type slicer-loader, forepoling hydraulic support, caterpillar track travelling hydraulic support and railless free-wheeled vehicle to carry out Pillar Recovery, stope efficient height, production capacity is higher relatively.Its system is simple, and equipment investment is few; Technology is flexible, the mechanization degree height, and equipment operation is flexible, and resettlement is fast, and organism of production is convenient.
Description of drawings
Accompanying drawing is that the dull pillar recovery method that room mining of the present invention is left over is implemented arrangement diagram.
Among the figure: the 1-caterpillar track travelling hydraulic support, 2-feed order, the 3-continuous miner, the 4-adhesive tape is along sending machine, 5-forepoling hydraulic support, 6-air curtain, 7-goaf, 8-drag conveyor.
The specific embodiment
Below in conjunction with accompanying drawing embodiments of the invention are further described:
The dull pillar recovery method that room mining of the present invention is left over:
1, before the back production at first to the local bare area of bordroom and the connection roadway intersection of big (length or width are greater than 8m), adopt anchor cable to add strong supporting, anchor cable is the high strength steel strand of 7 gangs of Φ 5mm, pallet adopts the processing of 12# channel-section steel, length 250mm, backing plate is the 8mm steel plate, specification 50 * 50mm, and array pitch is 2500mm * 2500mm between anchor cable; Anchor cable is with three resin anchoring agent anchorings (a CK2335 powder stick is preceding, and two middling speed K2350 powder sticks are in the back), and anchor cable anchors into roof and stablizes the rock stratum and be no less than 1500mm.
2, the coal-face subregion is reclaimed, the regular coal column of per three rows is an arrangement unit, from the coal column of leaving near goaf 7 one sides, between three regular coal columns of row and coal column, canvas air curtain 6 is set, make the regular coal column of three rows form air intake passage A and return air channel B, for stope provides fresh distinguished and admirable, with cloth air curtain 6 by frame fixation on coal column, the strict local available sandbag of ventilating ratio and brick construct be provided with airtight;
3, stay coal column from two defecations near goaf 7 sides, the regular coal column of per two rows is a back production unit, and each back production unit carries out back production by border F to main haulage roadway C direction;
4, continuous miner 3 is laid in two coal column positions of first trip of air intake passage A in the back production unit, arrange 2 caterpillar track travelling hydraulic supports 1 at continuous miner 3 rears, these 2 caterpillar track travelling hydraulic supports 1 are followed retreating of continuous miner 3 and are moved forward; And wait the to mine side of post of 2～3 row behind the first trip coal column is provided with 6 forepoling hydraulic supports 5, then at continuous miner 3 rears drag conveyor 8 and rubber conveyer 4 is set; The advance support distance of forepoling hydraulic support 5 reaches 24m, advance support distance greater than about 20m under the normal condition, use is closed in per two one assembly, strong point reach each other, leading area of stress influence to side in face of the back production has been carried out supporting, has effectively guaranteed the stability of work plane the place ahead bordroom and coal column;
5, mine by continuous miner 3, two coal columns of first trip are alternately implemented the feed of double-vane inclined cutout, Bian Caibian retreats, and during coal cutting, coal is loaded and unloaded in the drag conveyor 8 that is overlapped on continuous miner 3 back, by rubber conveyer 4 coal is transported again.
6,3 pairs of first trips of continuous miner about after two coal columns have respectively advanced a cutter, the caterpillar track travelling hydraulic support 1 at its rear portion in time step pitch of reach carries out supporting, the feed width of continuous miner 3 is about 3.3m, and angle is about 60 °, and depth of cut generally is as the criterion to cut the house column type coal column.Continuous miner 3 whenever advances a cutter, and promptly a step pitch is 0.6～0.8m; Coal mining feed order 2 by shown in the accompanying drawing 1., 2., 3., 4., 5., 6. hocket about the position.In order to help roof control, guarantee the safety of excavation personnel and equipment, the mining height of continuous miner 3 is safeguarded the height of former room mining, the spatial altitude after continuous miner 3 exploitations is highly consistent with the exploitation of former room mining like this; Roof collapse management top board if top board can not collapse voluntarily, must adopt the artificial way of caving of forcing to make roof collapse fully; In exploitation process, should be as far as possible that pillar extraction is clean, to prevent to form the isolated island coal column, do not utilize collapsing of top board to fall;
7, reclaimed two coal columns of first trip after, with forepoling hydraulic support 5 reach, caterpillar track travelling hydraulic support 1 and continuous miner 3 move forwards thereupon, the back production of two coal columns of continuation next line, repeating step 6 is until finishing a back production unit;
8, repeat above-mentioned institute in steps, until finishing the dull Pillar Recovery that all are left over.
The stope capital equipment is equipped with table
| Sequence number | Device name | Unit type | Quantity |
| ??1 | Continuous miner | ??EML340 | ??1 |
| ??2 | Caterpillar track travelling hydraulic support | ??2 | |
| ??3 | Advanced hydraulic support | ??6 | |
| ??4 | Drag conveyor | ??1 | |
| ??5 | Adhesive tape is along sending machine | ??1 |
Subordinate list 1 EML340 type continuous miner important technological parameters table
Appearance and size (length * wide * height) 11m * 3.3m * 2.05m cut width 3300mm
Operating voltage 1140V cutting height 2700～4600mm
The minimum terrain clearance 305mm of hauling speed 0.31m/s
Production capacity 15～27t/min adapts to the gradient ± 17 °
Complete machine weight 62t grounding pressure 0.19MPa
General power 587kW cylinder planted agent 205mm
Subordinate list 2 ZTZL6000/25/45 type advanced hydraulic support important technological parameters
????????????????????????????
Name parameter
????????????????????????????
Two one group of formulas of form
Height 2500～4500mm
Width 2465～4295mm
Working resistance 6000kN
Supporting intensity 0.61-0.77MPa
To floor pressure ratio Air holder 0.6-0.78MPa
Pumping plant pressure 31.5MPa
This operation of mode of operation
Pass step pitch from 600～800mm
Claims (1)
1. dull pillar recovery method that room mining is left over is characterized in that:
Reclaim a, subregion, the regular coal column of per three rows is an arrangement unit, from regular coal column near goaf (7) one sides, between three regular coal columns of row and coal column, air curtain (6) is set, make the regular coal column of three rows form air intake passage (A) and return air channel (B);
B, from the regular coal column of two rows near goaf (7) side, the regular coal column of per two rows is a back production unit, each back production unit carries out back production by border (F) to main haulage roadway (C) direction;
C, caterpillar track travelling hydraulic supports (1) and continuous miner (3) are laid in two coal column positions of first trip of air intake passage (A) in the back production unit, and wait the to mine side of post of 2～3 row behind the first trip coal column is provided with a plurality of forepoling hydraulic supports (5), then at continuous miner (3) rear drag conveyor (8) and rubber conveyer (4) is set;
D, two coal columns about first trip are alternately implemented the feed of double-vane inclined cutout, Bian Caibian retreats, and by the drag conveyor (8) that is located at continuous miner (3) rear coal is sent into rubber conveyer (4) in the coal mining process coal is transported;
E, continuous miner (3) be to after two coal columns have respectively advanced a cutter about first trip, and the caterpillar track travelling hydraulic support at its rear portion (1) step pitch that in time moves forward is carried out supporting;
F, reclaimed two coal columns of first trip after, forepoling hydraulic support (5) is moved forward, per two one group of forepoling hydraulic support, strong point reach each other, caterpillar track travelling hydraulic support (1) and continuous miner (3) move forward thereupon, continue the back production of two coal columns of next line, repeating step d and step e are until finishing a back production unit;
G, repeat above-mentioned institute in steps, until the recovery of finishing all dull coal columns of leaving over.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201010161124XA CN101858216B (en) | 2010-04-22 | 2010-04-22 | Method for recovering stagnant coal pillars left by breast type coal mining method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201010161124XA CN101858216B (en) | 2010-04-22 | 2010-04-22 | Method for recovering stagnant coal pillars left by breast type coal mining method |
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| CN101858216A true CN101858216A (en) | 2010-10-13 |
| CN101858216B CN101858216B (en) | 2012-05-23 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105240014A (en) * | 2015-11-12 | 2016-01-13 | 中国矿业大学 | Method for reclaiming house type remaining coal pillars based on filling and rebuilding of entry protection coal-pillar band |
| CN107882562A (en) * | 2016-09-29 | 2018-04-06 | 河南理工大学 | Double face arranges the implementation method of Pillar Recovery |
| CN109882176A (en) * | 2019-04-04 | 2019-06-14 | 中国矿业大学(北京) | Filling is adopted at end and hydraulic support cuts top gob side entry retaining double-vane alternately collaboration stoping method |
| CN110410076A (en) * | 2019-08-16 | 2019-11-05 | 山东科技大学 | A kind of filling mining method for leaving Pillar Recovery for old pillars of a house goaf |
| CN111119895A (en) * | 2019-12-24 | 2020-05-08 | 中国矿业大学(北京) | Recovery method of metal ore residual column |
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| RU2148712C1 (en) * | 1992-10-22 | 2000-05-10 | Закрытое акционерное общество "Корпорация "Университетские сети знаний" (УНИКОР) | Method for underground development of ore deposits |
| CN1482343A (en) * | 2002-09-09 | 2004-03-17 | 神华集团有限责任公司 | Continuous miner house column type short arm mechanized coal mining process and support equipment thereof |
| CN1858401A (en) * | 2006-05-31 | 2006-11-08 | 段连权 | Coal mining process including prop type mining and prop recovery |
| CN101126316A (en) * | 2007-09-19 | 2008-02-20 | 中国矿业大学 | Long-wall integrated-extraction reclaiming room-type coal column mining method |
| CN101487392A (en) * | 2008-01-16 | 2009-07-22 | 中国神华能源股份有限公司 | House pillar type coal mining method |
-
2010
- 2010-04-22 CN CN201010161124XA patent/CN101858216B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2148712C1 (en) * | 1992-10-22 | 2000-05-10 | Закрытое акционерное общество "Корпорация "Университетские сети знаний" (УНИКОР) | Method for underground development of ore deposits |
| CN1482343A (en) * | 2002-09-09 | 2004-03-17 | 神华集团有限责任公司 | Continuous miner house column type short arm mechanized coal mining process and support equipment thereof |
| CN1858401A (en) * | 2006-05-31 | 2006-11-08 | 段连权 | Coal mining process including prop type mining and prop recovery |
| CN101126316A (en) * | 2007-09-19 | 2008-02-20 | 中国矿业大学 | Long-wall integrated-extraction reclaiming room-type coal column mining method |
| CN101487392A (en) * | 2008-01-16 | 2009-07-22 | 中国神华能源股份有限公司 | House pillar type coal mining method |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105240014A (en) * | 2015-11-12 | 2016-01-13 | 中国矿业大学 | Method for reclaiming house type remaining coal pillars based on filling and rebuilding of entry protection coal-pillar band |
| CN105240014B (en) * | 2015-11-12 | 2017-09-15 | 中国矿业大学 | A kind of reconstruction protection pillar band that fills reclaims the method that room formula leaves coal column |
| CN107882562A (en) * | 2016-09-29 | 2018-04-06 | 河南理工大学 | Double face arranges the implementation method of Pillar Recovery |
| CN107882562B (en) * | 2016-09-29 | 2020-06-05 | 河南理工大学 | Method for realizing recovery of coal pillars arranged on opposite-pulling working face |
| CN109882176A (en) * | 2019-04-04 | 2019-06-14 | 中国矿业大学(北京) | Filling is adopted at end and hydraulic support cuts top gob side entry retaining double-vane alternately collaboration stoping method |
| CN110410076A (en) * | 2019-08-16 | 2019-11-05 | 山东科技大学 | A kind of filling mining method for leaving Pillar Recovery for old pillars of a house goaf |
| CN110410076B (en) * | 2019-08-16 | 2021-06-08 | 山东科技大学 | Filling mining method for recovering left coal pillars in goaf of old house pillar |
| CN111119895A (en) * | 2019-12-24 | 2020-05-08 | 中国矿业大学(北京) | Recovery method of metal ore residual column |
| CN111119895B (en) * | 2019-12-24 | 2022-01-11 | 中国矿业大学(北京) | Recovery method of metal ore residual column |
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| Publication number | Publication date |
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| CN101858216B (en) | 2012-05-23 |
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