CN101021154A - Thin basic rock shallow buried coal seam longwall face water retaining mining method - Google Patents

Abstract

The present invention relates to a shallow coal bed long-wall working face water-retaining mining method, specially it is applicable to safety production of shallow coal bed and water resource protection. Said method mainly includes the following steps: according to the coal bed geologic measurement information data defining mining working face; working face adopts hydraulic supporting frame whose strength is above 8000 KN to make support; selecting and using proper matched equipment for quickly driving said long-wall working face is above 200 m; adopting circulating operation to ensure that the dayly driving sped of the long-wall working face is above 15 m and making local filling and reducing local mining height so as to obtain good effect of protecting water resource.

Description

A kind of thin basic rock shallow buried coal seam longwall face water retaining exploitation method

Technical field

Patent of the present invention relates to a kind of thin basic rock shallow buried coal seam longwall face water retaining exploitation method; the raising, particularly bedrock thickness of protection, improvement of the ecological environment and coal recovery rate of safety in production, mine water resource that is particularly useful for shallow buried coal seam is at the shallow buried coal seam of mining height more than 10 times.

Background technology

The refreshing mansion in China western part-Dong wins the coalfield and is located in south, the northern Inner Mongol, Shaanxi, and proved reserves reach 2,236 hundred million tons, account for 1/3 of national proved reserves, belong to one of eight big coalfields, the world, are first hundred million tons of coal production bases of China.Because the coalfield is located in the black plain desert edge of hair, on to cover unconsolidated formation thickness bigger, be 0～76.33m, average 32m, and have a large amount of diving to exist covers basal water on the most areas coal seam, mining area and belongs to this type of.The sustainable development of shallow embedding coal field development and regional economy must be finished under ecological environmental condition in the continuous upgrading area, and this will the Efforts To Develop planting trees and grass, the greening mining area, checks winds and fixes drifting sand, and reduces soil erosion, is that graceful natural environment is built in coal field development.The construction of this environment be unable to do without water, does not have water, and life can't be survived, lack of water, and the coalfield can't be developed, and the contradiction of water conservation and coal mining is very outstanding.For so world-class big coalfield, it is particularly precious that water seems.Enough water resources are only arranged, could promote the sustainable and healthy development of coal field development and regional economy, harmonious co-existence between man and nature.

Most of coal seam, Shen Dong mining area belong to buried depth at 200m with interior shallow buried coal seam, shallow overburden, thin basement rock, on to cover thick loose aeolian accumulation sand bed be that the typical case in its coal seam composes and deposits feature, its basement rock top is generally by weathering simultaneously, the general 5～8m of severely-weathered band; The weak general thick 20m of weathered zone.In the shallow buried coal seam recovery process, no matter be the normal water burst of mine, still be that the people that purpose is carried out is sewer drainage and adopts the natural drainage of the water guide crack of formation to the coal measures aquifer with the control mine water disaster, the capital influences to some extent or destroys the aquifer, cause the significant wastage of surface water and groundwater resources, some water resources shortage mining area underground water in China western arid and semi-arid area are further run off and pollution, and groundwater level descends serious, and the desertification problem is serious day by day.Simultaneously, the security incidents such as the routed sand of the routed water of top board have all taken place in many collieries in exploitation shallow buried coal seam process, normally safety in production of impact, and the anti-routed Problems of Mining of water conservation is to develop the typical difficult problem that China western shallow-reserved coal seam faces always.At the typical shallow buried coal seam (bedrock thickness be generally less than 50m) of mining height below 10 times, general house pillar type coal mining method or the shortwall of adopting exploited at present, and goaf top plate is caving for bedrock thickness.As long as stay the coal column of the establishing unstability that do not collapse under pressure, water resource just can not run off.But at the shallow buried coal seam (bedrock thickness generally greater than 50m) of mining height more than 10 times, if still adopt above-mentioned coal-mining method, then coal resources waste is very serious for bedrock thickness, and this is an on-the-spot big problem anxious to be resolved.

Summary of the invention

At the problem that exists in the prior art, the purpose of this invention is to provide a kind of safety in production, cut the waste, environmental protection, thin basic rock shallow buried coal seam longwall face water retaining exploitation method that coal recovery rate is high.

For achieving the above object, water retaining mining method of the present invention is:

A. determine the exploitation working face according to coal geology metrical information data;

B. adopt the large scale coal wall of working face tilt length more than 200m, it moves towards to advance length as far as possible big in the scope of transporting equipment and geological conditions permission, and is not less than tilt length as far as possible;

C. work plane adopts the high-intensity hydraulic support of support force more than 8000kN to support, and step occurs to prevent face roof, forms the gushing water passage;

D. select to be fit to the corollary equipment that the coal wall advances fast, and adopt cycle operation, assurance coal wall day fltting speed is more than 15m;

E. in time adopt the Local treatment measure, partial stowage or local reduce mining height in 10～50m scope near the open-off cut zone to reduce the mining overburden through crack, make basement rock that whole dislocation type not take place and destroy; And near first weighting zone, old top in 10～50m scope, local reduce mining height or in its corresponding face of land coverage local slip casting make overlying strata form comparatively stable masonry girder construction to reduce the migration space of overlying strata, strengthen the mining overburden resistance effect.

Adopt said method, can make the maximum dynamic deformation value of mining overburden activity less than the static deformation value, and maximum dynamic deformation value will reduce with the increase of face propulsion speed.The large scale face propulsion speed is more fast, overlying strata sink more mild, its globality is more strong, water guide cranny development degree is more little, just equal comparatively speaking to have delayed the disrumpent feelings of basement rock, prolonged its stable time that blocks water, can effectively prevent the extraction space and on cover the communication of mining overburden conduit pipe between the loose aquifer water body.Simultaneously, under the quick propulsioning condition of working face, horizon d integral body cuts, the loose aeolian accumulation layer of sand in top can not form self mechanical structure, sink with roof is synchronously whole, covering under the effect of unconsolidated formation weight stress, its original structural fracture and adopt the crack and can be compacted faster and make up, lose the storage water guiding action, become water barrier.This method fwaater resources protection is effective, can keep the safety in production, cuts the waste, environmental protection, coal recovery rate height.

The specific embodiment

Thin basic rock shallow buried coal seam longwall face water retaining exploitation method of the present invention, the information that provides according to geological survey at first, analyze the hydrogeological parameter of overlying strata, determine the scope of coal wall exploitation and need the timely key area that adopts Local treatment, to reduce phreatic loss.Select high-intensity hydraulic support, guarantee in broadwall that enough support setting loads can be controlled to shear disrumpent feelingsly at first to be begun by goaf side, step occurs to prevent face roof, form the gushing water passage.According to the long-term experience with mining in the coal wall, in the coal wall, guarantee the bracket leg support force more than 8000kN, can prevent effectively that face roof from step occurring and sinking or the landing unstability.Select the heavy corollary equipment of the high-power and high-reliability that is fit to fast mining, the requirement that advances fast to reach working face.The overhaul life of working face capital equipment is longer than the service time of a working face, is not needing well servicing during the working face mining, the requirement that advances fast to reach working face.Adopt regular " three or eight " or " four or six " cycle operation, be coal cutting, move frame, pushing and sliding, the coal-winning machine front roll cuts the top coal, back roll cuts ground coal, the termination feed of cutting sth. askew, the endless form of two-way coal cutting day is advanced more than 20 cuttves, cut deeply more than 0.8m, make coal wall day fltting speed more than 15m.Use the work plane technology of moving fast, realize fast guaranteeing that by tomography the large scale work plane advances fast.In time adopt the Local treatment measure, because near the open-off cut be area of stress concentration, the top board basement rock generally will take place to shear disrumpent feelings in the open-off cut side, near open-off cut, carry out partial stowage or reduce mining height, to improve the stress state of local top board, reduce the dynamic pressure destructiveness, reduce the overlying strata through crack, make basement rock that whole dislocation type not take place and destroy, make and adopt water guide cranny development height and be reduced.According to production practices, partial stowage or local reduce mining height in open-off cut near zone 10～50m scope can effectively reduce and adopt water guide cranny development height.Near first weighting zone, old top in 10～50m scope, local reduce mining height or in its corresponding face of land coverage local slip casting to reduce the migration space of overlying strata, suitably reduce mining height is to reduce the migration space on basic top, being conducive to the crack that disrumpent feelings sillar turns round in the opposite direction by working face one side is extruded, and the extruding closing motion of this end check seam is effectively to prevent top board infiltration or the water of bursting, and be conducive to basic top and form comparatively stable structure, thereby thin basement rock destructiveness is reduced, effectively strengthen the mining overburden resistance effect.Local slip casting in the bottom influences scope of the corresponding water-bearing layer of Qi Laoding first weighting can effectively prevent communication water-bearing layer, water guide crack, and the coverage size can be determined by the fracturation angle.After work plane is adopted, coal seam goaf overlying rock absciss layer is disrumpent feelings, the rock stratum is in migration process, have vertically downward and around the work to the central horizontal migration both direction component of force that moves, its make a concerted effort with around component can form ring work plane goaf be bordering on two groups of vertical fine cracks with its trend, based on the crack around the ring work plane goaf.The tilt length of work plane is big more, it is more little to adopt the boundary effect that rock mass influences by the work plane both sides, and the rock stratum is partial to generally more based on the integral body migration, and resistance effect is good more, facts have proved that after face length reaches 200m the boundary effect of work plane mining overburden is no longer obvious.From this viewpoint, the tilt length of working face advances length more big with moving towards, and more is conducive to water-retaining production, so will adopt the large scale coal wall.

Claims (1)

1. thin basic rock shallow buried coal seam longwall face water retaining exploitation method is characterized in that:

A. determine the exploitation working face according to coal geology metrical information data;

B. adopt the large scale coal wall of working face tilt length more than 200m, it moves towards to advance length as far as possible big in the scope of transporting equipment and geological conditions permission, and is not less than tilt length as far as possible;

C. work plane adopts the high-intensity hydraulic support of support force more than 8000kN to support, and step occurs to prevent face roof, forms the gushing water passage;

D. select to be fit to the corollary equipment that the coal wall advances fast, and adopt cycle operation, assurance coal wall day fltting speed is more than 15m;

E. in time adopt the Local treatment measure, partial stowage or local reduce mining height in 10～50m scope near the open-off cut zone to reduce the mining overburden through crack, make basement rock that whole dislocation type not take place and destroy; And near first weighting zone, old top in 10～50m scope, local reduce mining height or in its corresponding face of land coverage local slip casting make overlying strata form comparatively stable masonry girder construction to reduce the migration space of overlying strata, strengthen the mining overburden resistance effect.