RU1795102C - Method for mining potassium outburst-prone beds - Google Patents

Abstract

Usage: to increase the safety of the development of rocks in the hazardous area and reduce downtime and damage to the mechanized complex, Summary of the invention: when opening the molds of hazardous rocks at the bottom, measure the length of the segment, calculate its arrow, remove the next strip with a width equal to the length of the arrow of the segment, then when in the recess of the next strip, the combine is stopped at a safe distance from the middle of the segment, the value of which is determined from the expression (h + ht + + h2) tg (Z where R is the radius of the hazard zone, h is the arrow ment, hi and h2 are the widths of the strips to be removed, and a is the angle of direction of the outlet of the salt-gas flow, the angle a being taken to be equal to the angle at which bore holes are drilled to form a cavity for the release of the salt-gas flow, and the initiation of the emission and discharge of the salt-gas flow is performed tiy. 1 s.p., f-ly, 4 ill.

Description

The invention relates to the mining industry and, in particular, is intended for the safe development of potash outburst formations with a pillar mining system.

A known method of reducing the intensity of the emission of salt and gas, taken as a prototype. The method consists in conducting mine workings, determining the critical exposure area and boundaries of the outburst hazardous rocks, initiating the outburst by drilling and blasting operations, discharging the salt and gas stream through the wells with a delay in the bulk of the destroyed rock by a jumper from non-outburst hazardous rocks.

The disadvantages of this method are: increased risk of mining operations, its low efficiency,

due to the mismatch of the process parameters with the size of the hazardous area and the difficulty of implementing drilling operations in cramped spaces. conditions of the bottom-hole part of the lava, which causes downtime and damage to the mechanisms of the mechanized complex.

The aim of the invention is to increase the safety of the development process of rocks of the hazardous area and reduce downtime and damage to the mechanisms of the mechanized complex.

In FIG. 1 shows a section of a plan of lava at the level of the rocks of the roof and a diagram of the set and calculated parameters of the hazardous zone within the rocks of the immersion trough; in FIG. 2 is a plan of a surface for drilling and blasting holes and a surface for drilling and blasting holes and an outlet surface; Fig.Z - section along

Xi

YU

ate about

YU

the middle fan of the holes in the vertical plane; in FIG. 4 - section along the fan in the plane of the holes.

In FIG., The following designations are adopted: 1 - the line of the face before drilling holes. 2 - rocks of the hazardous zone of the immersion trough with a contoured radius; 3 - a ledge angle located at a safety distance L and intended to create a safe environment when drilling holes for drilling and blasting; 4 - the surface of the outlet (shaded); 5 - ledge angle lines; 6 - basic non-hazardous breeds; 7 — holes that are drilled parallel to each other to the right and left of the ledge line at an angle of about. and intended to create an outlet and expose the hazardous rocks; 8 - holes that are drilled with diverging fans to the right and left of the ledge line and designed to initiate outburst rocks; 9 - section mechanized lining; 10 - bending downhole conveyor; 11 - racks, reinforcing at the time of BVR, a vertical organ wall.

A potassium salt (sylvinite) layer is mined using a pillar mining system, and a long working face is formed 1. There is an outburst zone ahead of the face in the rocks (dipping trough) 2, which must be crossed by the face 1. The sign of the trough is visually detected when it is cut by the combine to a depth h by the appearance of a characteristic synclinal deflection of the rock layer (segment) in the upper edge of the bottom (the mold can be geometrically represented as a spherical body. Tape measure or other measuring tool by measuring the bottom, the deflection length of the rock (segment) layer is A. The hydroficated support 9, the conveyor 10 are retracted (conventionally shown in Fig. 1). Then, the rock strip of a given width hi, which ends on the start line of the segment, is again removed by the harvester ( deflection) on the previous face a length A. If the arrow is more than half of the capture of the executive body of the combine, then the value of hi is taken to be equal to half of the capture of the combine, if the arrow is less than half of the capture, the value of hi can be taken equal to the width of the capture of the combine. The obtained numerical values determine the value of h according to the well-known formula

in 4 / 1G, T

. h- 2A + Ttf4 where B-4 ();

 hi

(3)

(4)

S is the increment of the segment length at the subsequent bottom;

a is the length of the segment at the previous face;

hi is the given width of the strip of rock.

Next, determine the boundary of the rocks of the hazard zone R according to the formula „2

R

8-h

+ 0.5h

(5)

fifteen

twenty

25

thirty

35

40

45

fifty

55

From the results obtained, we determine the safe distance L by the formula

HR- (h + hi + h2) tg a (6)

In doing so, the following sequence of operations is followed. After removing a strip of width hi, the lining 9 and the conveyor 10 are retracted, then a strip of width h2 is removed to form a ledge 3 at a safe distance L defined by formula 6.

The combine is driven away to a safe distance (approximately 25-30 m) from the ledge 3. Taking into account the bending radius of the conveyor 10, we latch it, starting from the ledge 3 and, having retreated from it by an amount (1.5-2 m), slide the support 9 and they form a free space in the form of a pocket with a length B set by an angle a, equal to, for example, 45 ° and taking into account R and L, determine the length of the holes 8 and the parameters of the fans so that at least half of the volume of the rocks in the hazardous area is covered by drilling and blasting operations, Using the known experimental data, we determine the area of the outlet holes 4. Then at an angle parallel to each other there are a number of holes 7 to form the outlet 4 (the number of holes is determined by the passport of the blast gun, based on the explosion for ejection). The length of the holes 7 is taken equal to the width of the strip of the main rocks 6. Drill holes 8 according to the passport BVR, calculated on the basis of shock blowing in the rocks of the hazardous area. Before loading holes 7, 8, a fence is installed along the length B to prevent the rock from entering the area of mechanisms, as is currently being done in mines. The guardrail is made of reinforcing iron or wood shields and rests on the soil or conveyor and roof supports or lowered roof peaks (not shown in the figures, since this is a known solution). To reinforce the ledge 3, a vertical organ wall 11 is installed before charging the holes. The holes are charged and blown up. Since between

In the event of explosive explosion of rocks in the hazardous area and the development of the ejection process, a slowdown of the order of 30-45 m s is observed, which allows an outlet to be formed during the blasting of holes 7. The rock of the hazardous zone is activated by shock blasting of holes 8 and the process develops ejection and degassing of rocks. Part of the rocks through the hole is ejected into the bottomhole space at an angle a and placed in the pocket of the subline B. Since the ejection develops in the volume of rocks of the hazardous area, the rock that is not ejected through the outlet is delayed in the zone itself, and the gases exit through the hole , which brings the zone rocks to a non-hazardous state.

We drill 8 hole fans to initiate ejected rocks. The BVR passport is calculated based on the condition of blasting holes 7 for ejection, and holes 8 for crushing, and when crushing with drilling and blasting operations, they cover a rock volume equal to 70% of the volume of a sphere of radius R. They enclose the complex zone along the length m and Derevnymi shields (not shown in the figure), the most weakened angle of the ledge 3 is reinforced with an organ 11 and the holes are charged. Blasting operations are carried out in accordance with the requirements of the industry normative document Measures to ensure safe operations during the elimination of sudden releases of salt and gas using blasting in areas of local geological disturbances (immersion trough).

Further advancement of the mine face for the extraction of reservoir reserves

It is made according to the usual technological scheme after evaluating the effectiveness of the measures taken by the known method and effectively ventilating the lava.

The use of this method provides an increase in the safety and efficiency of mining in the rocks of the hazardous area, since elimination of the hazardous nature of the targeting, due to the practical determination of the size of the hazardous rocks, which is not possible to achieve with any existing or basic method. The basic method is the method used in potash mines to initiate explosion hazardous zone rocks to be ejected by drilling and blasting operations. This emission is caused in the plane perpendicular to the bottom, firstly, and secondly, the boundaries of the outburst hazardous rocks are conditionally accepted without the necessary, preliminary determination. All this makes this basic method not effective enough.

The direction of the ejected saline-gas flow at an angle to the bottom reduces the force impact of the rock on the mechanized support, evenly distributes the rock along the length of the face, does not curl the inter-rack space, which resulted in quick cleaning of the ejected rock and putting the complex into operation. Comparison of the results obtained by the proposed method with the results of the direct initiation of BWR of rocks of the hazardous zone to the emission perpendicular to the face (a 90 °) (analogue used in mines) showed that in the second method the total costs are two or more times higher.

Claims (2)

SUMMARY OF THE INVENTION 1. A method for developing potash outburst hazardous formations, including a pillar mining of a formation by a mechanized complex, drilling holes in the hole through a bridge from the main rocks, exposing a multitude of outburst rocks, initiating their ejection, discharging a salt-gas flow through the formed cavities, characterized in that in order to increase the safety of the development of rocks of the ejection zone and to reduce downtime and damage to the mechanisms of the mechanized complex, when opening troughs of outburst hazardous rocks at the bottom face measure the length of the segment, calculate its arrow, remove the next strip with a width equal to the length of the arrow of the segment, then when digging the next strip with the width, the combine is stopped at a safe distance from the middle of the segment, the value of which is determined from the expression HFHh + hi + h2) tg a where R is the radius of the hazard zone; h is the boom of the segment; hi and h2 are the width of the strips; a is the angle of the direction of discharge of the salt-gas stream, the angle "being taken equal to the angle at which the holes are drilled to form a cavity for discharging the salt-gas stream, and the ejection and discharge of the salt-gas stream is initiated after performing the indicated measures. 2. The method according to claim 1, characterized in that the holes for forming the outlet cavity are drilled parallel to each other at an angle of discharge of the salt-gas flow towards the face to the boundary of the hazardous area, holes are drilled in the horizontal and vertical planes with fans covering at least half of the volume of the hazardous area into the boreholes to initiate the ejection, while the bulkhead is blown out to discharge, and rocks within the limits of the hazardous area explode in the erase mode. FIG. 4