CN110080767B - Overlap joint arrangement method for layered mining working face of thick coal seam - Google Patents
Overlap joint arrangement method for layered mining working face of thick coal seam Download PDFInfo
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Abstract
The invention relates to a coal seam mining method, and discloses a thick coal seam layered mining working face lap joint arrangement method; the method is characterized in that the gate grooves on the right side of each layer below the first layer of the previous section and the gate grooves on the right side of the first layer are arranged in a staggered mode, the internal staggered distance is half to two lanes in one lane, and the gate grooves on the left side of each layer except the lowest layer of the subsequent section are inserted into corresponding positions right below and overlapped with the gate grooves on the right side of the first layer of the previous section from left to bottom; the invention changes the current situation of traditional layered mining with coal pillars left, and improves the mining rate; the stress of the gate arranged below the goaf is low, and the maintenance cost of the roadway is low; and the upper part of the upper section is layered and paved for one time, so that the lower part of the upper section is layered and staggered layers inserted into the adjacent sections obliquely downwards are used for two times, and the lapping utilization rate is increased.
Description
Technical Field
The invention relates to a mining method of a coal seam, in particular to a layered mining method of a thick coal seam layered mining working face lap joint arrangement technology.
Background
The thick coal seam mining plays an important role in the well mining of China, and the yield and the reserve account for about 45 percent. The middle part of the 20 th century and the 80 th year is a boundary point of the mining method of the thick coal seam in China, and the thick coal seam is mainly mined by a layering method in China for a long time.
The so-called stratified mining is a method of manually dividing a thick coal seam into a plurality of coal seams suitable for primary mining and then mining layer by layer. Typically, each layer is between 2-3 m to facilitate the placement of work surfaces, roadways, etc. The layered mining occupies an important position in the mining history of China, and more than one fourth of once total output of important coal mines in China is mined by the layered mining.
According to different layering division modes, the layering mainly comprises horizontal layering, inclined layering and inclined layering, and the specific layering needs to be selected according to different geological conditions. Various mining modes can be obtained according to the layering division, the mining sequence among layers and the like. Common methods are an inclined layered upward filling coal mining method and an inclined layered downward caving coal mining method. The inclined layered descending caving coal mining method is a main mining method adopted by China for medium-thickness coal seams in the 20 th century, wherein after first layered mining, the lower layer is mined under the cross-falling rock, and in order to ensure the safety of the coal mining working surface of the lower layer, an artificial roof, such as a plastic net or a metal net, is laid on the upper layer.
The upper and lower layered working faces in the same section can be simultaneously stoped under the condition of keeping a certain offset distance, and the stoping is called layered simultaneous stoping. Or after a layer is mined in the section, after a certain time, after the roof is basically stable, a lower layer roadway is tunneled, and then the mining is carried out, which is called as the layered mining. In the process of layered mining, if an upper layer and a lower layer are mined simultaneously, a certain offset distance needs to be ensured between the upper working face and the lower working face, so that the overlying rock movement of the upper working face tends to be stable in the mining process of the lower working face. Generally, the lower layered working surface is later than the upper layered working surface by about 3-4 months. When the basic jack is relatively hard and the immediate jack is relatively thin, the offset and the interval time can be appropriately shortened.
In the layered mining, the lower layered working face roadway has various arrangement forms, and as shown in fig. 1, the lower layered working face roadway can be divided into an outer staggered type, an overlapped type and an inner staggered type. When a thick coal seam is mined, the mutual positions of all the layered drifts have great influence on the use and maintenance conditions of the drifts. The staggered arrangement mode can cause that all layered roadways are affected by the supporting pressure, the roadway pressure is large, and the roadway maintenance is difficult. The internal staggered type roadway is directly arranged at the edge below the stabilized goaf and is positioned in a pressure relief area below the goaf, the pressure of surrounding rocks of the roadway is low, and the roadway is easy to support. However, no matter what arrangement mode is adopted, coal pillars between two sections cannot be avoided, the coal pillars are concentrated in stress to bring about some mine pressure control problems, the coal pillars cause ground subsidence, wave breaking and fluctuation, and the problem of low section extraction rate is difficult to solve for a long time.
Disclosure of Invention
The invention overcomes the defects in the prior art, provides a lapping arrangement method for a thick coal seam layered mining working face, changes the current situation of traditional layered mining coal pillar mining, and solves the problems of ground subsidence, wave breaking and fluctuation and low district mining rate caused by coal pillars.
The invention is realized by the following technical scheme.
A lapping arrangement method for a layered mining working surface of a thick coal seam comprises the following steps:
a) and determining the number of layers mined in layers according to the total thickness of the coal seam, so that the thickness of each layer is the thickness of the full height of the fully mechanized mining at one time.
b) Arranging a first section working surface: the right crossheading of the working surface of the first section is arranged in a staggered manner, the staggered arrangement is that the right crossheading of the first layer of the working surface of the first section exceeds the distance of 1-2 roadway widths of the right crossheading of the second layer of the working surface of the first section, and the internal offset distance is required to be not more than the distance of two roadway widths for maximally extracting coal. The working face right crossheading below the second layer of working face is overlapped, so that the first layer of working face right crossheading of the first section is staggered by the distance of 1-2 roadway widths of all layered working face right crossheading on the lower part. Namely, no matter the layers are divided, the right crossheading of the first layered working face is staggered by the distance of one to two roadway widths of the right crossheading of all the lower layered working faces.
c) Arranging a second section working surface: the left crossheading of the first-layer working face of the second section working face is arranged below the first-layer working face of the first section, and the first-layer working face of the first section are arranged in a staggered manner, so that coal is mined maximally, and the internal staggered distance is less than the distance between two roadway widths; the first-layer working surface of the second section working surface slopes from the left crossheading side of the first-layer working surface to completely enter the first-layer working surface of the second section; meanwhile, except for the lowest part of the layer, the working surfaces below the second layer working surface of the second section are overlapped in a left crossheading way; the right gate way of the working surface of the second section and the right gate way of the working surface of the first section are arranged in the same way.
d) And d, repeating the steps a-c to sequentially arrange the subsequent working surfaces until all the working surfaces are arranged.
Furthermore, the left gate grooves of each layer of the first section working surface are arranged in an overlapping mode or in a staggered mode.
Furthermore, the first-layer working face left crossheading of the second-section working face in the step c is arranged below the first-layer working face right crossheading of the first section, and a small coal pillar is arranged between the first-layer working face left crossheading of the second-section working face and the first-section second-layer working face right crossheading at an interval so as to isolate a left goaf.
Preferably, the first-layer working surface of the second section working surface is tightly attached to the first-layer working surface of the first section along the left groove.
Further preferably, the slope distance of the slope is 10-15m, and the gradual transition of the support is ensured.
Compared with the prior art, the invention has the beneficial effects that.
According to the overlapping arrangement method for the layered mining working faces of the thick coal seam, the current situation of the traditional layered mining remaining coal pillar mining is changed, the layered gateway on the upper part of the rear section is obliquely inserted below the corresponding layered goaf of the working face of the front section, at least one half of the coal pillars between the adjacent sections are recovered, and the mining rate is improved; secondly, the problems of difficult mine pressure control, ground subsidence, wave breaking and fluctuation and low section extraction rate caused by coal pillar stress concentration are solved. The stress of the gate arranged below the goaf is low, and the maintenance cost of the roadway is low; and thirdly, the upper section is layered and paved for one time, and the lower layer of the section and the staggered layer crossheading inserted into the adjacent section obliquely downwards are used for two times, so that the lapping utilization rate is increased.
Drawings
FIG. 1 is a schematic diagram of a common arrangement of strata under two-strata mining.
Fig. 2 is a schematic view of the gate way arrangement in two-layer mining according to the present invention.
Fig. 3 is a schematic diagram of the gate way arrangement in three-layer mining according to the invention.
The working face of the first layer of the first section is 1, the right crossheading of the working face of the first layer of the first section is 2, the second layer of the first section is 3, the right crossheading of the second layer of the first section is 4, the first layered working face of the second section is 5, the left crossheading of the first layered working face of the second section is 6, the second layer of the second section is 7, the left crossheading of each layer of the working face of the first section is 8, the third layer of the first section is 9, the right crossheading of the third layer of the working face of the first section is 10, the left crossheading of the second layer of the working face of the second section is 11, and the third layer of the second section is 12.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail with reference to the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The technical solution of the present invention is described in detail below with reference to the embodiments and the drawings, but the scope of protection is not limited thereto.
Example 1
A lapping arrangement method for a layered mining working surface of a thick coal seam comprises the following steps:
the first step is as follows: determining the number of layers mined in layers according to the total thickness of the coal seam, so that the thickness of each layer is the thickness of the full height of the fully mechanized mining for one time; for example, the average coal thickness of the No. 3 coal seam of the coal field on the plateau is 5.3 m, and if mining is carried out in three layers, the thickness of each layer is lower, so that the mining is planned to be carried out in two layers, the height of each layer is 2.65 m, and the coal mining machine is suitable for cutting coal once.
The second step is that: arranging a first section working surface: the coal field on the plateau is divided into two layers and arranged according to the arrangement mode of figure 2. The left crossroads 8 of each layer of the working surface of the first section are arranged in an overlapping way; the working surface of the first section is arranged in a right-crossheading staggered mode, namely arranged in a staggered mode: the right gate way 2 of the first layer working face 1 of the first section exceeds the right gate way 4 of the second layer working face 3 of the first section by the distance of half to two lane widths;
the third step: arranging a second section working surface: the left gate way 6 of the first layer working face 5 of the second section working face is obliquely inserted into the goaf lower part of the first layer working face 1 of the first section towards the left lower part and is overlapped with the right gate way 2 of the first layer working face 1 of the first section. While the other side lanes are in line with the normal layout. Therefore, the left end of the first layered working surface of the two sections forms a slowly inclined section, the working surface gradually transits to the level after gentle slope rising, the slope rising distance is 15m, and the gradual transition of the support is ensured. While the running surface 7 of the second section second layer coincides with the first section second layer 3.
The fourth step: and determining the mining sequence among the layered working faces. Mining is carried out according to the sequence of the sections from left to right and from top to bottom in a layering mode. The first floor face 1 of the first zone is mined first, then the second floor face 3 of the first zone is mined, then the first floor face 5 of the second zone face is mined, and finally the second floor face 7 of the second zone is mined, and so on.
The overlap arrangement method of the working face of the stratified mining of the thick coal seam changes the current situation of the traditional mining of the remaining coal pillars of the stratified mining, the crossheading of the stratum with the upper position of the rear section is obliquely inserted below the corresponding stratified goaf of the working face of the front section, at least half of the coal pillars between the adjacent sections are recycled (half is recycled when the coal pillars are divided into two layers, the more the quantity of the strata is, the higher the mining rate is, and the mining rate is improved). And secondly, the stress of the gate arranged below the goaf is low, and the maintenance cost of the roadway is low. In addition, the upper part of the upper section is layered and paved for one time, and the lower part of the upper section and the staggered layer crossheading inserted into the adjacent section in the inclined downward direction are used for two times, so that the lapping utilization rate is increased.
Example 2
As shown in fig. 3, the working face layout is a schematic diagram of dividing the coal seam into 3 layers, and the left gate grooves 8 of the first section working face are arranged in an overlapping manner; the working surface of the first section is arranged in a right-crossheading staggered mode, namely arranged in a staggered mode: the right gate way 2 of the first layer working face 1 of the first section exceeds the right gate way 4 of the second layer working face 3 of the first section by the distance of half to two lane widths; the right gate groove 10 of the third layer working surface 9 of the first section is arranged overlapping the right gate groove 4 of the second layer working surface 3 of the first section.
Arranging a second section working surface: the left gate way 6 of the first layer working face 5 of the second section working face is obliquely inserted into the goaf lower part of the first layer working face 1 of the first section towards the left lower part and is overlapped with the right gate way 2 of the first layer working face 1 of the first section. The left gateway 11 of the second section second layer working surface 7 is obliquely inserted into the goaf lower part of the first layer working surface 5 of the second section working surface towards the left lower part and is overlapped with the left gateway 6 of the first layer working surface 5 of the second section working surface. While the other side lanes are in line with the normal layout. Therefore, the left ends of the first layered working surface of the two sections and the second layered working surface 7 of the second section form a slowly inclined section, the working surfaces gradually transition to the horizontal level after gradual slope rising, the slope rising distance is 13m, and the gradual transition of the support is ensured. While the second section third layer work surface 12 is arranged in a straight-groove manner in line with the first section second layer work surface 3.
The fourth step: and determining the mining sequence among the layered working faces. Mining is carried out according to the sequence of the sections from left to right and from top to bottom in a layering mode. First mining the first floor face 1 of the first zone, then mining the second floor face 3 of the first zone, then mining the third floor face 9 of the first zone, then mining the first floor face 5 of the second zone face, mining the second floor face 7 of the second zone, and finally mining the third floor face 12 of the second zone, and so on.
While the invention has been described in further detail with reference to specific preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (5)
1. A lapping arrangement method for a layered mining working surface of a thick coal seam is characterized by comprising the following steps:
a) determining the number of layers mined in layers according to the total thickness of the coal seam, so that the thickness of each layer is the thickness of the full height of the fully mechanized mining for one time;
b) arranging a first section working surface: the right crossheading staggered arrangement of the working surfaces of the first section is that the right crossheading (2) of the first layer of working surface (1) of the first section exceeds the right crossheading (4) of the second layer of working surface (3) of the first section by 1-2 roadway widths, and the right crossheading of the working surfaces below the second layer of working surface (3) of the first section is overlapped so that the right crossheading (2) of the first layer of working surface (1) of the first section is staggered by 1-2 roadway widths of all the layered working surfaces below the right crossheading (2) of the first layer of working surface of the first section;
c) arranging a second section working surface: the left gate way (6) of the first-layer working face (5) of the second section working face is arranged below the first-layer working face (1) of the first section and is arranged in a staggered manner with the first-layer working face (1) of the first section, and the internal staggered distance is less than the distance of two roadway widths; the first-layer working surface (5) of the second section working surface slopes from one side of the left gate way (6) to completely enter the first layer of the second section working surface; meanwhile, except for the lowest part of the layer, the working surfaces below the second layer working surface (7) of the second section are arranged in an overlapping way at the left side; the right gate way of the working surface of the second section and the right gate way of the working surface of the first section are arranged in the same way;
d) and d, repeating the steps a-c to sequentially arrange the subsequent working surfaces until all the working surfaces are arranged.
2. The method for overlapping and arranging the working faces of the stratified mining of the thick coal seam according to claim 1, wherein the left gate grooves of the layers of the working face of the first section are arranged in an overlapping manner or in a staggered manner.
3. The overlap arrangement method for the thick coal seam layered mining working face according to claim 1, characterized in that the left crossheading (6) of the first layered working face (5) of the second section working face in step c is arranged below the right crossheading (2) of the first layer working face (1) of the first section, and a small coal pillar is arranged between the left crossheading (6) of the first layered working face (5) of the second section working face and the right crossheading (4) of the second layer working face (3) of the first section to isolate the left goaf.
4. A method of overlapping a working face for stratified mining of a thick coal seam as claimed in claim 1 or 3 wherein the left gate way (6) of the first stratified working face (5) of the second zone of working faces is adjacent to the first stratified working face (1) of the first zone of working faces.
5. The overlap joint arrangement method for the working face of the stratified mining of the thick coal seam according to claim 1, wherein the slope rising distance of the slope rising is 10-15m, so that the gradual transition of the support is ensured, and the slope rising distance is the horizontal distance of the working face gradually rising from the gate way of the lower stratum to the upper stratum.
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| US20220282619A1 (en) * | 2021-05-25 | 2022-09-08 | Taiyuan University Of Technology | Method and device for carrying out grouting between adjacent gateroads in internal-staggered split-level coal mining |
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| CN112377194A (en) * | 2020-11-06 | 2021-02-19 | 窑街煤电集团有限公司 | Method for preventing rock burst by staggered arrangement of mining working face roadway |
| CN114000902B (en) * | 2021-09-22 | 2022-12-27 | 中国矿业大学(北京) | Method for suspension maintenance of broken roof of negative coal pillar roadway by grouting reinforced anchor rod |
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| RU2029087C1 (en) * | 1991-05-31 | 1995-02-20 | Всероссийский научно-исследовательский и проектно-конструкторский институт добычи угля гидравлическим способом | Method for mining of thick steeply dipping coal seams |
| CN1078301C (en) * | 1998-02-18 | 2002-01-23 | 中国矿业大学（北京校区） | All thickness coal mining method for seam misplaced coal tunnel distribution on thick seam |
| RU2301333C2 (en) * | 2005-08-10 | 2007-06-20 | Государственное образовательное учреждение высшего профессионального образования "Южно-Российский государственный технический университет" (Новочеркасский политехнический институт) | Method for extracting low and average thickness beds across the run with rock left in mine |
| RU2303694C1 (en) * | 2006-03-28 | 2007-07-27 | Государственное образовательное учреждение высшего профессионального образования "Санкт-Петербургский государственный горный институт имени Г.В. Плеханова (технический университет)" | Method for thick coal bed development |
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| CN107060763A (en) * | 2017-07-03 | 2017-08-18 | 中国矿业大学(北京) | A kind of method for realizing pole close-in seamses economy, safety and high-efficiency mining |
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| CN108266189A (en) * | 2018-01-26 | 2018-07-10 | 太原理工大学 | A kind of lane top Tunnelling Along Goaf goaf isolation method |
| CN108952716B (en) * | 2018-06-22 | 2020-06-09 | 太原理工大学 | Thick coal seam longwall working face multi-lane arrangement method |
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| US20220282619A1 (en) * | 2021-05-25 | 2022-09-08 | Taiyuan University Of Technology | Method and device for carrying out grouting between adjacent gateroads in internal-staggered split-level coal mining |
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