Pingyi development technology

According to the relative position of the main flat and the deposit, the main flat position can be divided into two types: along the vein and through the vein. Along the pulse, it can be extrapulmonary or intrapulmonary, but it is mostly external to the pulse. The penetrating ridge can be vertical, or it can have a certain angle of intersection with the strike; it can be the lower plate or the upper plate, or it can be biased toward the wing of the ore body. Subject to terrain, industrial site, external transportation and mining technical conditions, there are possibilities, but as long as the conditions allow the following discs to develop.

According to different mining systems, the development of Pingshuo can be divided into stage flat and main level.

The stage is developed in a flat manner, and the ore can be directly transported to the plant or user by means of mine cars, cars, ground rail ramps and simple ropeways. This development method can not cut the auxiliary shaft and the slip well, so it has the advantages of small amount of infrastructure construction, low investment and fast production. However, the pits are scattered, the transportation distance is long and there are many links, the operation cost is high, and the output is small, so it is mostly used for small mine development.

The main flat is to open up, and the ore at each stage above the main level can be lowered to the level of the main level by the downhole. The main flat is transported to the surface by the electric car, belt conveyor or car. Personnel, equipment, materials, auxiliary shafts, elevator shafts, inclined shafts or trackless ramps are sent to the work surface. There are also flats on the ground with rail ramps or car links.

When the ore and surrounding rock are stable, the ore is mostly discharged through the well to the main flat. When the ore and surrounding rock are not stable, the position of the well can be selected through several engineering holes in different locations; after the stages are opened, after the engineering geological survey, the rock or ore is well stabilized. The ore-boring well is cut; if the rock and ore are found in the mine, the well can be reinforced.

In small mines, especially small mines with large height differences, it is feasible to use ore, inclined shafts or surface slopes to lower ore due to large amount of wells and high investment, but the operating costs are high. When the ore has agglomeration, self-ignitability, or has a certain quality requirement for the ore block, or the ore and surrounding rock are extremely unstable, it is not appropriate to use the shaft or the inclined shaft to lower the ore. When there is a condition for non-rail transportation, it can also be transported by car on a ramp.

The waste rock is discarded and can be disposed along the slope contours through the flat exits of each stage under the conditions of topography and environmental protection. Otherwise, the secondary well can be used to refer to the surface or the upper stage and then abandon it. If the main flat is outside, the valley with sufficient volume on the surface can discard the waste rock, or it can be discharged into the valley through the special waste rock through the main flat.

Compared with other pioneering methods, Pingyi has the following advantages:

(1) The ore is discharged by the self-weight of the shaft, and the mine water is discharged to the surface through the main level or stage, saving energy and low production cost;

(2) The mining system is simple, with large equipment and low investment;

(3) The construction method and construction equipment are simple;

(4) The production is safe and reliable, and the potential is large. When the expansion and expansion is small, the investment is quick and effective;

(5) In addition to Changping, in general, the construction speed is fast and the construction time is short. Especially when using the stage to develop, there are many working faces at the same time, especially so. As SHOUWANGFEN copper mine, Yimen Bureau of Mines and the Lion Fengshan Copper, copper and other Hujiayu are put into operation in a shorter period.

The Pingyi development method has been widely used in high mountains in China and has achieved good results.

First, the determination of the elevation of the main flat mouth

From the perspective of mineral deposit development, the lower the elevation of the main flat shovel, the more reserves will be developed with the flat raft. However, the elevation of the main level is often limited by the elevation of the ore deposit of the ground mine, which must be adapted to the elevation of the mine.

When the ore main adit electric locomotive directly transported to bunker by beneficiation plant, the main adit port downhill elevation should reach 3 ~ 4 ‰ receiving bunker receiving mine mouth elevation; the use of automobiles or belt When the conveyor is transported, it is determined by the terrain and the allowable running slope of the equipment. Sometimes the ore needs to be shipped out, and the ore level of the mine bin is related to the loading height (with or without a mine bin) (loading a train or loading a car); if it is transported by an aerial ropeway, the elevation of the mine mouth It should be able to meet the needs of the height difference of the coarse, medium and ropeway stations. When the elevation of the ore is very different from the height of the main flat, the ore needs to be transported to reach the plant. At this time, it is determined only by the reasonable elevation of the main flat.

In some mines, the main flat sluice and the concentrating plant are uncoordinated by the ore level of the mine bin, causing the electric car to move uphill, thus affecting the traction of the electric car. In addition to special conditions, it should generally be avoided.

Second, the determination of single and double lanes

The single and double lanes of the main flat are related to the productivity of the mine, the specifications of the transport equipment, the length of the main flat and the stability of the rock formation.

Small and medium-sized mines that use rail transportation are mostly transported by monorail, and if necessary, the wrong lane can be added. Large-scale mines, especially large and extra-large mines developed by Changpingyu, have large sections for the main flats, such as stable rock, joints and cracks, and do not pass large structural belts. Single lane double rail flat boring can be used, otherwise double lane single rail flat boring should be used. When using the double lane flat, when an accident occurs in a flat road and cannot continue to dig, the other flat raft can still continue to dig, and the contact roadway can be drilled at a suitable position to restore the construction of the accident flat. Flat construction is critical and is also conducive to transportation and ventilation during excavation and easy to manage during production. However, the double lanes have a large amount of excavation and high investment. Therefore, when selecting the machine, it is necessary to make a decision after careful analysis and comparison.

When using railless transportation or belt conveyor and trackless combined transportation, due to the large section, double lane development is generally used. Small mines can also be developed with single lanes.

Third, the problems that should be paid attention to in the development of Changping

In China, the mines developed by Changpingyu are used, and the main flat is 3~5km long. The Henderson molybdenum mine in the United States has a length of 15.8km. Despite this, it is still reasonable to use Pingyi. However, the following issues need to be addressed to make the advantages of this program more prominent.

(1) Changpingyu is a controlled project for the summer construction of mines. Because the main flat is too long, it must take a long time for infrastructure construction. In order to speed up the progress of the project and shorten the excavation time of the main flat, it can be in a place with suitable terrain. Opening measures (can be flat, inclined or shaft) to increase the working face.

(2) If the mining industry site is built near the main Pingkou, the personnel must enter from the pass, and then the auxiliary well can be upgraded to reach the work surface, thus increasing the workers' upper and lower working hours and shortening the pure working time; The pressure gas pipeline enters from the sputum, which increases the loss of pressure and pressure, reduces the pressure and pressure of the working face, and the transportation time of equipment and materials is also long. These factors have an adverse effect on labor productivity. Therefore, where conditions permit, the mining industry site, located near the wellhead of the auxiliary well, will improve the above problems.

(3) Long Pingyu excavation, especially the long flat shovel with large water inflow, avoiding downhill as much as possible.