RU2276265C1 - Development method for composite seams characterized by gob layers - Google Patents

Abstract

FIELD: mining, particularly underground flat seams development with selective mineral excavation.

SUBSTANCE: method involves selectively excavating mineral by several entry ways, which are close to excavated space; performing roof control by laying rubble strip in excavated space, which is formed by entry ways forming from gob layers, wherein the gob is obtained by developing adjacent entry ways; laying layer of gob obtained by previous entry way forming on the strip; repeating operations of selective two next entry ways excavation and serially laying one gob layer onto another layer adjoining the rubble strip; installing pneumatic cylinders on gob strip; supplying compressed air in the pneumatic cylinders to expand the pneumatic cylinders between the roof and rubble strip; laying timber supports on rubble strip between the cylinders, wherein the supports have heights exceeding collapsed pneumatic cylinder height; lowering roof; removing the pneumatic cylinders from rubble strip in points of roof contact with timber supports. Rubble strip widths and distance between them is equal to summary width of two entry ways. Rubble strip height is determined from mathematical equation with taking into consideration summary thickness of gob layers in total coal seam thickness and degree of rock fragmentation.

EFFECT: reduced mineral mining losses and increased roof control efficiency.

4 dwg

Description

The invention relates to the field of mining and can be used in underground mining of shallow formations with selective extraction of minerals.

Known methods for the development of shallow mineral strata with unstable roof rocks, including mining the mineral stratum with cameras (short working faces), installing lining in the chambers, leaving supporting and pliable pillars of the mineral between the chambers (author certificate No. 1270334, class E 21 C 41/04).

The disadvantages of these methods are low productivity and high complexity of treatment, high cost and large losses of minerals in pillars.

Known methods for developing shallow mineral strata with unstable roof rocks, including mining the mineral stratum with cameras, installing lining in the chambers and leaving interchamber pillars of the mineral (Yu.F. Vasyuchkov, Mining, Moscow, Nedra, 1990, p. 284 -286).

The disadvantages of these methods are low productivity and high complexity of treatment works and large (40-50% or more) loss of minerals in pillars.

A known method (A.S. No. 941583, class E 21 C 41/04) of developing shallow mineral formations with unstable roof rocks, including mining the mineral stratum with cameras, leaving interchamber pillars of the mineral, erecting rock bands in the chambers, and working off interchamber pillars by secondary cameras. The disadvantages of this method are the low productivity of sewage treatment and large operational losses of minerals in the inter-chamber pillars. These shortcomings are associated mainly with the relatively small chamber width of 3-5 m, which does not allow the efficient use of modern high-performance treatment equipment and mineral delivery vehicles.

A known method of developing formations of complex structure with interlayers of gangue (A.S. No. 909178, M. Cl. E 21 C 41/04, B.I. No. 81982), taken as a prototype, including selective extraction of minerals by panels, control the roof and the placement of the broken rock layer in the worked-out space, while the panel is divided into two parts by width, while the part of the panel adjacent to the previously worked out is developed with a long face with a complete collapse of the roof, and the part of the panel adjacent to the untouched array is developed by a camera lava with abandonment pillars, moreover, the extraction of minerals and the placement of the broken rock layer in the lava chamber are advanced with respect to the part of the panel worked by the long face by an amount exceeding the zone of influence of the reference pressure of the lagging part of the panel, and the length of the lava chamber is taken based on the placement conditions it contains waste rock, but not less than the zone of influence of the reference pressure of the lagging part of the panel.

The disadvantages of this method are the large operational losses of the mineral in the inter-chamber pillars and the low efficiency of roof management.

The technical result achieved by using the proposed method is to reduce operational losses of minerals and increase the efficiency of roof management.

The technical result is achieved by the fact that in the method of developing formations of complex structure with interbeds of waste rock, including selective excavation by mineral fillings, roof management and placement of the broken rock layer in the worked out space, according to the invention, the fillings are cut into the worked-out space, and the roof is controlled by laying out rubble stripes in the mined-out space formed when conducting calls at the beginning of interlayers of gangue obtained by mining near laid entry, and then on the same strip lay a layer of waste rock with a subsequent sunset, after which the operations of selectively excavating two subsequent runs and laying out alternately one layer of empty rock on another adjacent to the previously created rubble strip, is repeated after the rock strip is erected on they install pneumatic balloons and supply compressed air to them, bursting pneumatic balloons between the roof and the rubble strip, and between the pneumatic balloons wooden supports are laid on the rubble strip, the height of which takes more than the height you bellows in the folded state, then the points of contact with the wooden roof supports bellows rubble removed from the strip, the width butovyh strips and the distance between them equal to the width of two take zahodok, rubble and the height h _bp band is selected from the relation:

h _bp = 2m _p to _p , (m)

where m _p - the total thickness of the layers of waste rock in the total thickness m _{of the} reservoir, m;

to _p - coefficient of loosening of rocks.

The invention is illustrated by drawings, where in Fig.1 shows a diagram of the extraction of minerals by long faces with the location of the rock strips parallel to the line of the face, in Fig.2 is a section along the line aa, Fig.3 is a section along the line bb . Figure 4 - structural column of the formation of complex structure.

The process is carried out as follows: the selective recess shale formations complex structure is performed in a direction from the vehicle 1 to the ventilation 2 drifts stope (0, I, II, III, IV ) of length l _Lake stope (Figure 1).. (The width of the entry l _s when excavating a layer of oil shale is approximately 1.8 m). The rock (limestone) obtained from the interlayers during the excavation of the deposit I of the oil shale formation is laid next to the spent deposit 0 (Fig. 1), then the deposit II is worked out, and the limestone obtained during the excavation of the oil shale layer is again laid into the previously worked deposit 0 , forming a rubble strip with a width equal to the value of the sunset l _s . After that, deposit III is worked out and the limestone obtained during the development of the oil shale formation is laid out in sunset I, then sunset IV is worked out, and the rock obtained from the interlayers of empty rocks is laid out into the sunset, forming a rubble strip 3 with a width equal to two dimensions of sunset l _s . On butovoj strip along the length of the longwall l _Lake laid bellows 4. Air springs are placed in the desynchronization with a distance approximately equal to two values _of l stope. Compressed air is supplied to the pneumatic cylinders, bursting them between the roof and the rubble strip, and wooden supports 5 are laid on the sides of the pneumatic cylinders. It is difficult to install the supports tightly between the rubble strip and the roof, therefore, the supports are installed with some minimum clearance A (Fig. 3). (As wooden supports (gaskets), for example, beams, mine racks, sleepers, boards, etc. can be used.) The height of the wooden supports h _Δ (Fig. 3) (gaskets) is greater than the height of the air cylinders when folded (air from the air cylinder is released ) condition. With the removal of the face from the installed pneumocylinders, the lowering of the roof rocks occurs with different intensities. In the immediate vicinity of the face, the rate of lowering of the roof rocks has maximum values. As you move away from the bottom of the hole, the speeds decrease and at a certain distance l _pr , depending on the geological conditions of the formation, stabilize (i.e. do not change significantly in the future) or become practically equal to zero. The roof has dropped by Δ (Fig. 1, Fig. 3). Here, the roof comes in contact with wooden supports, after which the air balloons are unloaded and removed from the rock band. Unloading of pneumocylinders consists in the release of air from them. The unloaded pneumocylinder is transferred to the face line.

After that, operations to remove the next entries, lay the rubble strips from the gaps of empty rocks, install pneumocylinders and wooden supports between them, unload and remove the pneumocylinders at the points of contact of the roof with wooden supports are repeated, while the width of the rubble strips and the distance between them are taken equal to the width of two entry l _s , and the height of the rubble strip h _{bp is} chosen from the ratio:

h _bp = 2m _p to _p (m),

where m _p - the total thickness of the interlayers of waste rock (m _p = m _1-2 + m _2-3 + m _3-4 ), m ₁ , m ₂ , m ₃ , m ₄ - the power of the first, second, third and fourth, respectively layers of slate in the total thickness m _{o of the} reservoir, m, am _1-2 - thickness of the layer between the first and second layer of slate, m, m _2-3 - thickness of the layer between the second and third layer of slate, m, m _3-4 - thickness of the layer between the third and fourth layer of slate, m (figure 4);

to _p - coefficient of loosening of rocks.

Using the proposed method for mining a complex formation will reduce the operational losses of oil shale and increase the efficiency of roof management.

Claims (1)

A method of developing formations of complex structure with interbeds of waste rock, including selective excavation by mineral fillings, roof management and placement of the broken rock layer in the worked out space, characterized in that the cuts are cut into the worked out space, and the roof is controlled by laying out the rubble strip in the worked out space, formed during the entry, first from the interlayers of waste rock obtained by the development of a nearby entry, and then into the same strip they lay a layer of waste rock with a subsequent run-in, after which operations to selectively remove two subsequent runs and lay out one layer of waste rock alternately on the other adjacent to the previously created rubble strip, repeat, after erecting the rock strip, pneumocylinders are installed on it and compressed air is supplied to them , bursting air bellows between the roof and the rubble strip, and between the air bellows on the rubble strip lay wooden supports whose height is greater than the height of the pneumatic balloon when folded, then in the contact points with wooden roof supports bellows rubble removed from the strip, the width butovyh strips and the distance between them equal to the width of two take zahodok and the height h butovoj _bp band is selected from the relation h _bp = 2m _p to _p , (m), where m _p - the total thickness of the layers of waste rock in the total thickness of the reservoir, m; to _p - coefficient of loosening of rocks.

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