Mine mining and mining technology flow

Guide

The characteristics of the mining and mining method are: the stage is divided into ore blocks, and the ore blocks are further divided into mine houses and pillars for secondary recovery. The mining room is stratified and collected from bottom to top. Each time the ore that has collapsed is released about one-third, and the rest is stored in the mining room as a workbench to continue mining, and then released after the mining room is finished.

First, the method features

The characteristics of the mining and mining method are: the stage is divided into ore blocks, and the ore blocks are further divided into mine houses and pillars for secondary recovery. The mining room is stratified and collected from bottom to top. Each time the ore that has collapsed is released about one-third, and the rest is stored in the mining room as a workbench to continue mining, and then released after the mining room is finished. After the mining house is finished, return to the mining column and treat the goaf.

Second, the applicable conditions

The mining and mining method is mainly used to mine ore and rock ore. Although the thickness of the ore body is not limited, when it exceeds 5 m, the technical and economic effects are not as good as those of the deep hole and medium-deep hole ore mining stage, and the general application is less. The inclination of the ore body: in the thin vein, the general requirement is not less than 60°, and in the medium-thick ore body, the general requirement is not less than 55°. The smaller the dip angle, the more difficult it is to mine, and the volume of powder mine loss and the workload of the field. Because a large amount of ore is stored in the mine, the storage period is often as long as 1 to 3 years. Therefore, the ore and surrounding rock cannot be self-igniting, oxidizing and agglomerating; high-sulfur deposits and radioactive ore should be used with caution.

Third, the structural parameters

In the thin and extremely thin veins, the stage height is 40-50m for most mines; 50~60m is used under the condition that the dip angle of the vein is very steep (above 60°), the ore and surrounding rock are stable and the elements are stable. The dip angle of the vein is between 50 ° and 60 °, the ore and surrounding rock are not stable, or the ore body has a sudden change, and 30 to 40 m is used. The top column is about 3m thick; if the ore grade is high, the upper return airway does not need to be retained or left.

The height of the bottom column is generally 3 to 3.5 m on the roof of the transportation roadway. If the surrounding rock is stable and the wood source is extensive, it may not be left, and the false bottom is used instead of the bottom column. The funnel spacing is 4-6 m when using a wooden funnel, and 6-7 m when using a vibrating miner. The length of the nuggets is generally 40 to 60 m, and 100 to 120 m is also used. If the surrounding rock and ore are very stable, a central patio is arranged in the middle of the nugget, and a smoothing patio is arranged at both ends. The width of the mine is generally the same as the thickness of the vein, but it should not be less than 0.8m. The width of the bottom space should not be less than 1.2m, and should be layered on a sub-standard and then gradually reduced to the width of the design.

Generally do not leave a column, replace the stage patio with a parallel patio; sometimes leave 2m on each side of the patio.

In the medium-thick ore body, the stage height is generally 40-60 m, and the ore body with more complicated elements is 35-40 m. The thickness of the top column depends on the stability of the ore and the thickness of the ore body, and varies between 4 and 6 m. The height of the bottom column can be 5~6m if it is mined by wooden funnel or vibrating miner, and 9~14m by electric picking. The length of the nugget is generally not more than 50m. The width of the mine is no more than 12m. The exposed area of ​​the ore roof should be controlled within 500m2 and the maximum should not exceed 50m2 to reduce the normal workload and ridge loss. The width of the column depends on the stability of the ore and surrounding rock, generally 8 to 12 m. The ore and surrounding rock are very stable and take a small value, and vice versa. The parameters used in several major mines are shown in Table 1.

Fourth, pick and cut

The transport lanes are generally driven along the lower veins along the veins. The patio is drilled along the veins in the thin veins, so that the veins are located in the center of the section of the atrium to facilitate prospecting. In the medium-thick ore body, it is generally located in the lower part of the ore body, in order to reduce the length of the hole in the mining column. It can also be placed in the center of the horizontal section of the column. The upper and lower exits of the patio should be located in the side walls of the tunnel. The contact road is used to connect the mine and the patio.

Generally, one is drilled every 5 to 6 m vertical height from the patio. In the medium-thick ore body, the bottom structure of the electric roadway is commonly used. The roof of the electric roadway is separated from the roof of the transportation roadway by the ore discharge shaft, which can store more than one ore of the train, generally 3~4m. The lower exit of the ore-boring well is located on the side of the transport lane or the tunnel; the upper exit is located in the center line of the ramp and the other side is located in the side wall of the ramp; the inclination should not be less than 60°. A bucket is drilled every 5~6m, and its length is based on the principle of 1/2~2/3 of the width of the ore covered by the ore flowing into the ramp, usually taking 3.5~4m.

Cutting includes bottoming and leaking. In the nugget of the bottom column, the height of the bottom space is 2m, the area is the same as that of the mine house, but the minimum width should not be less than 1.2m; the leakage is generally from the bottom space to expand the upper part of the neck into a bell mouth, or After digging 2m on the neck, continue to dig and expand to the surrounding area to form a bell mouth and a bottom space. In the pit wood bottom pit, the bottom is very simple, that is, the top of the roof of the transport roadway is raised upwards by about 3m, and the false alley and the funnel are built.

Five, mining

The mining includes rock drilling and blasting, layout and ore, flat field, treatment of turquoise and broken large blocks. In the stope with a smooth patio, it also includes a pacing patio. Rock drilling commonly used 01-45, YSP-45 and other upward rock drilling machines to the blasthole, hole depth of 1.5 ~ 1.8m, also use YT-25 and other gas leg rock drill to level or slightly tilt the blasthole, hole depth 2 ~ 3m . The blasting mainly uses safe explosives such as ammonium nitrate, ammonium oil and ammonium pine wax, and uses non-electrical detonation such as fire detonators or detonating tubes. Each time the ore that has collapsed, 35 to 40% is released, so that the working space for recovery is maintained at a height of 2 m. The flat field and the handling of the turquoise are still manual labor, and the workers are physically exhausted.

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