RU2398966C1 - Method for mining thick steeply inclined and steep coal beds - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: method of mining includes separation of mine sections by slopes into sections, mechanical excavation of coal by combine in horizontal or flat layers in descending order by long cuts along length, transportation of coal, filling of mined space with cast hardening mixture. Loose coal from faces is transported along chutes by hydraulic transport, after mining of cuts, chutes are covered with the same chutes to form technological mines after cuts are filled with hardening mixture. In order to transfer combine into underlying layer, spiral cut is worked, with lower size along height compared to cut from slope to roof and back to bed soil at the level of overlying level, with the possibility of combine movement after mining of overlying layer along spiral mine, to expand its size along height to size of cuts. Spiral mine serves for hydraulic transport of coal and ventilation of mine.

EFFECT: increased efficiency of mining face operation and improved safety of mining.

4 cl, 8 dwg

Description

The present invention relates to mining and can be used in the development of powerful steeply inclined and steep coal seams.

There is a method of developing powerful steep formations with hydraulic breaking with cast hardening tab (Patent No. 2069752).

The disadvantage of this method is the high complexity of conducting and attaching sub-floor drifts. For effective coal breakdown, it is necessary to create a water pressure higher than the coal compressive strength. At present, hydraulic heads create a water pressure of 14-16 MPa. At this pressure, hydraulic breaking is effective for coal compressive strength up to 10 MPa with a water flow rate of about 10 m ³ / t of coal production. At stronger coals of 15–20 MPa and more, the water flow increases to 30 m ³ / t and the process of hydraulic breaking becomes ineffective. For the destruction of coal, it is necessary to use drilling and blasting, which disrupts the continuity of the extraction of coal and reduces the efficiency of the faces.

The next disadvantage of the technology is the large size of the outcrop of lateral rocks in the bays (at least 8 m in height), which creates a risk of dumping and collapse of coal, containing rocks and the stowing mass. In this case, the process of mining coal, managing the state of the lateral rocks and the backfill array becomes uncontrolled, which reduces the safety of mining.

The closest analogue to the claimed invention is the "Method for the development of powerful steep coal seams in horizontal layers in a descending order" (AS No. 866194).

The essence of this method lies in the fact that the excavation field is divided by slopes into sections, the mining of which is carried out by horizontal (slightly inclined) layers in a descending order with mechanized excavation of the layers by the combine with long runs along the strike, transporting coal and laying the worked out space with a cast hardening mixture.

The disadvantage of this method is the lack of effectiveness of the working face for the extraction and transportation of coal. Coal is transported by self-propelled wagons and the extraction of coal is cyclical. As a result, the harvester is idle for a significant part of its working time.

Another disadvantage of this method is that the ventilation of the face is carried out by a local ventilation fan, which reduces the safety of mining. Aeration of treatment faces with local ventilation fans is allowed only with the permission of the territorial authority of Rostekhnadzor (Safety rules in coal mines, p.192 PB 05-618-03). When developing coal seams with high gas content, there may be a danger of gas contamination of the faces, and this method of ventilation of the faces may not be allowed.

The technical problem solved in the present invention is to increase the efficiency of the working faces while increasing the safety of mining.

The problem is solved in that in the proposed method for the development of powerful coal seams of steep and steeply inclined incidence, including dividing the excavation field with slopes into sections, mechanized excavation of coal by a combine with horizontal (slightly inclined) layers in a descending order by long runs along the strike, transporting coal, laying the mined-out space hardening with a mixture, beaten coal from the faces is transported through the gutters by hydrotransport; after working out the gutters, the gutters are covered with the same gutters to form technological workings after laying the gaps with a hardening mixture.

Technological workings formed from the gutters are used as air ducts for ventilating long passages due to the mine depression, as well as for draining water from flushing the filling pipeline.

The layers are worked out initially by primary passages, between which pillars are left, which are worked off by secondary passages after laying the primary passages and curing the filling mixture.

When working out the underlying layer of the gutter in the workings, dismantle and lay on the soil an entry for hydrotransport of coal.

To transfer the harvester to the underlying layer, pass a spiral mining of a smaller size in height than the runs from the slope to the roof and back to the formation soil to the level of the overlying layer, the harvester moves after the mining of the overlying layer along the spiral working, expands its height in size to the dimensions of the drillings, and spiral production is used for hydrotransport of coal and ventilation of the face.

Distinctive features of the claimed method from the prototype are the following:

- beaten coal from the faces is transported through the gutters by hydrotransport. The use of coal hydrotransport from the bottom to the storage chamber allows for almost continuous coal extraction by the combine, since the gutters are laid on the production soil and the pipes for water supply are built up after about 10 m of bottom movement and takes up a small part of the working time. This achieves an increase in the efficiency of the working face.

- after working out the gutters, the gutters are covered with the same gutters for the formation of technological workings after the bookmarks are laid with a hardening mixture.

- Technological workings formed from gutters are used as air ducts for ventilating long passages due to mine depression, as well as for draining water from flushing of the filling pipeline. The use of gutters both for transporting coal and for the formation of technological workings that serve as air ducts for ventilating the faces and draining water from washing the filling pipeline eliminates the need to transport the gutters before they are laid, sinking or erecting ventilation workings, thereby reducing labor intensity auxiliary works and increases the efficiency of the faces.

After laying the entry hardening mixture, the pipelines are washed with water. As a rule, water is discharged to the backfill array, which leads to a decrease in its strength and siltation of the mine workings. With water drainage from flushing pipelines through gutters (technological workings), all other things being equal, the strength of the filling mass can be increased, therefore, the economy and safety of mining.

- development of the layers is carried out first by primary passages, between which pillars are left, which work off secondary passages after laying the primary passages and curing the filling mixture. Alternate extraction of primary and secondary openings allows continuous extraction of coal in the layer and at the same time laying openings with a hardening mixture, which increases the efficiency of coal mining.

- when working out the underlying layer of the gutter in the workings, dismantle and lay on the soil an entry for coal hydrotransport. This operation eliminates the need to transport the gutters during coal extraction, which increases the efficiency of the work.

- for transferring the combine into the underlying layer, spiral workings of a smaller size in height are used than cuts from the slope to the roof and back to the formation soil to the level of the overlying layer. The combine after mining the overlying layer moves along the spiral mine, expands its size in height to the size of the entries, and the spiral mine serves for the hydrotransport of coal and ventilation of the face. The passage of the spiral workings is combined in time with the excavation of the overlying layers, so that the harvester, after working out the next layer, moves to the lower layer, without stopping the work on the extraction of coal. It also increases the efficiency of the working faces.

The set of distinctive features characterizing the method allows to increase the efficiency of the working faces while increasing the safety of mining.

The invention is illustrated by the description of a specific, but not limiting example of implementation and the accompanying drawings.

Figure 1 - General view of the diptera excavation field in the plane of the coal seam; figure 2 is a transverse section of the formation along the central slope; figure 3 is a transverse section of the formation along the flank slope; figure 4 is a transverse section of the formation along the flank slope at the level of the developed layer; figure 5 - spiral development in plan; figure 6 - face, a longitudinal section of the entry; Fig.7 - face in the plan; on Fig is a diagram of the bookmark of long entries.

The method is as follows.

An excavation field measuring 200-300 m along the strike (Fig. 1) is opened from field drifts 1 and 2 (Figs. 2, 3), respectively, on the ventilation and discharge horizons with cross-bars 3, 4, 5 and 6, 7, 8. Between the discharge and flaps 9, 10 and central 11 slopes are carried out by ventilation ditches in the lying side of the formation. The excavation field is divided by the central slope into two wings (sections). The central slope 11 (figure 2) is used to divert the outgoing air stream, moving people, delivering materials and equipment, placing filling and flushing pipelines. Flank slopes (figure 3) are used for opening and preparing horizontal layers, supplying fresh air to the working faces, moving people, transporting coal pulp, placing pressure head water conduit and electric cables.

The development of the sections is carried out by slightly inclined layers 12, 13 (Fig. 1) 3-4 m high, depending on the stability of the coal mass in a descending order. An angle of inclination of layers of 5-6 ° is necessary for the gravity transportation of coal and filling mixture in castings.

Coal mining begins from flank cross-taps 3, 5 with the passage of the unit vectors, for example, K75GD combines to the top of the seam. The layers are worked out by long runs 3-4 m wide along the strike of the formation. Ventilation of faces during mining of the first layer is carried out by fans of local ventilation, and during mining of subsequent layers due to mine depression. The fastening of the orths and approaches during the development of the first layer is carried out with a wooden frame support. Initially, primary approaches 14, 15, 16 from the top of the formation are worked out, between which pillars of the same size as the entries are left (figure 4). The coal is broken off by a combine 17. A monitor is installed on the working body of the combine through which water under a pressure of 3-3.5 MPa is supplied to the face to flush the coal. Transportation of coal from the bottom - by gravity by hydrotransport through the gutters 18 (Fig.6, 7) to the flank slopes, in which the coal pulp flows through the pipes to the haulage horizon in the hydraulic chambers 19 (Fig.3). As the face moves, the troughs 18 (Fig. 7) are laid on the entry soil and the pressure conduit 20 is built up. After completing the entry to the central unit, the combine 17 is returned to the flank unit and the development of the next entry is started (Fig. 4).

The bookmark of fulfilled bookings is made in the following sequence (Fig. 8). Preparation of the developed space for the reception of cast hardening mixture is in progress. For this, the gutters laid on the soil of the entry are covered with the same gutters, fastened together and thus form the technological production 21 on the soil of each entry (Fig. 4). The production data, after laying in the openings with the hardening mixture, serve as air ducts for ventilating the faces during mining of the underlying layer. At the interface with the flanking unit, a jumper 22 is erected (Fig. 8); the second jumper 23 is erected after 40-50 m. The cast hardening mixture from the filling complex (not shown in Fig.) through the pipe 24 laid in the central ramp 11, is fed directly through the central ort 25 directly behind the jumper 23. After filling the space between the jumpers, the hardening mixture sent to another pipeline, and the previous one is washed with water and shortened to the next jumper. Water from the flushing of the pipeline is discharged in front of the jumper 23 and it is discharged to the drainage horizon into the sump by the outlet 21 located under the filling array (not shown in the drawings). Having finished the bookmark of another sunset, they again serve the hardening mixture in the prepared space.

After practicing the primary calls begin to excavate the secondary 26, 27 (figure 4). By the time of working out the secondary entries, the filling array in the primary entries should gain the necessary strength (1.5-2.0 MPa). A set of such strength requires approximately 7-8 days from the moment of bookmark entry. With this in mind, choose the length of the excavation field.

The development of the second and subsequent layers is carried out under the protection of an artificial array. To increase the stability of the artificial array, the lower layer sunset (Fig. 4) is offset relative to the upper sunset, i.e. arranged in a checkerboard pattern. When excavations are long at the roof and formation soil, lateral rocks are reinforced with metal anchors. If necessary, the sides of the entry in the coal mass are strengthened with wooden or bamboo anchors.

The notch in the lower layer is the same as the notch in the upper one. Airing of the working face is carried out due to the mine depression: a fresh stream of air enters through the flank slope 9 into the unit 28 (Fig. 3), then into the insert 29 and through the production line (air duct) 21 (Fig. 6, 7) goes to the central slope 11 (figure 1). When working out the gutter openings in the technological workings 21, they are dismantled and laid on the soil of the workings for coal hydrotransport. Due to this, there is no need to remove the gutters from the passages before submitting the bookmarks and bring them into the passages during their development.

To transfer the harvester to the lower layer, spiral workings 30 are smaller in height than the cuts (Figs. 4, 5). Spiral workings pass one to two layers ahead of the flank slopes 9, 10 to the top of the formation and then rise to the soil to the level of the overlying layer. The workings are fixed with a wooden frame support. After working off the next layer, the combine passes to the lower layer by spiral working, while its height increases in size to the size of the cuts. Chipped coal is also transported through gutters. After transferring the harvester to the underlying layer, the flank slopes at the level of the soil of the worked out layer are isolated, and the isolated part of the slope, spiral working and the last worked approach are laid with a hardening mixture. Thus, the transfer of the harvester to the lower layer is also carried out under the protection of the artificial array. When developing subsequent layers, the technological cycle is repeated.

Thus, this method allows continuous extraction and transportation of coal, aeration of the face due to mine depression, which increases the efficiency of the working faces and the safety of mining.

Claims (4)

1. A method of developing powerful steep and steeply sloping coal seams, including dividing the excavation field with slopes into sections, mechanized excavation of the coal by a combine with horizontal or slightly inclined layers in descending order by long runs along the strike, transporting coal, laying the worked out space with a cast hardening mixture, characterized in that chipped coal from the faces is transported along the gutters by hydrotransport, after working out the gutters, the gutters are covered with the same gutters to form a process workings after laying the openings with the hardening mixture, in order to transfer the combine into the underlying layer, pass the spiral working of a smaller size than the openings from the ramp to the roof and back to the formation soil to the level of the overlying layer, with the possibility of the combine moving after working the overlying layer on a spiral mine to expand its size in height to the size of the openings, and the spiral mine serves for the hydrotransport of coal and ventilation of the face. 2. The method according to claim 1, characterized in that the technological workings formed from the gutters are used as air ducts to ventilate long passages due to a shaft depression, as well as to divert water from flushing the filling pipeline. 3. The method according to claim 1, characterized in that the working off of the layers is carried out first by primary passages, between which pillars are left, which are worked off by secondary passages after laying the primary passages and curing the filling mixture. 4. The method according to claim 1, characterized in that when working out the underlying layer of the gutter in the workings, dismantle and lay on the soil an entry for coal hydrotransport.

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