All mineral deposits or parts of a mining enterprise are classified as ore fields. In a mining enterprise, all or all of the deposits that are classified as one mine (pit) are called minefields, as shown in Figure 5-2. A field is sometimes equal to a mine field and sometimes includes several well fields.
When the scope of the deposit is large, the ore body is relatively concentrated. For the convenience of production management, a mine field can be used for mining. On the contrary, if the deposit is large or the ore body is relatively scattered, such as using a mine field to mine all the deposits, the amount of roadway excavated is large, and the production location is too scattered, which is economically unreasonable. At this time, it should be divided into several wells. . When mining a large deposit, to determine a reasonable range of wells, the following factors must be considered:
(1) National regulations on mine construction time and annual output
(2) The degree of exploration of the deposit
(3) Deposit burial characteristics
The quantity and thickness of the ore body, whether there is geological damage, and whether there are no ore belts of different scales. Under normal circumstances, in order to make a well field with sufficient reserves, and from the convenience of production management and safety management, the length of the ore body is 500~800m or 1,000-1 500m, and the depth is 500~600m. It is reasonable to use a mine field for mining. of. When mining thick or buried deep deposits, small well size can be adopted to facilitate phased construction and extensive use of small and medium-sized equipment.
Surface topography (4) the existence of mines rivers, lakes, the availability of iron ore and so on through the route.
(5) Economic effects
(6) Reliability of safe production
Second, the stage, the nuggets and panels, mining areas
(1) Stage, nuggets
Stage
In the mining of gently inclined, inclined and steeply inclined deposits, the main transport lanes are consistently oriented at a certain vertical distance in the well field, and the minefield is divided into sections in the vertical direction. This section is called the stage. The scope of the phase is limited to the boundary of the well field and is limited to the two main transport lanes above and below the slope. The stage height refers to the vertical distance between the transport lanes of the upper and lower adjacent stages.
2. Nugget
In the phase along the strike, the tunnel is connected to the upper and lower adjacent stages of transporting the alleys, and the stage is divided into independent mining units, called ore blocks.
(2) Panels and mining areas
Panel
In the mining level and micro-sloping deposits, if the thickness of the deposit does not exceed the allowable stage height, the stage is no longer divided in the well. At this time, in order to facilitate mining work, the mine tunnel roadway is divided into rectangular ore sections, which are called panel sections. The extent of the panel is the length of the minefield, and the distance between the lanes of the two adjacent panels is its width.
2. Mining area
At a certain distance in the panel, the tunnel is connected to the adjacent two lanes, and the panel is subdivided into independent mining units. This unit is called the mining area.
Third, the mining order of the deposit
(1) Mining sequence in the mine field
When mining in the stage, the mining sequence in the middle stage of the mine field is divided into two types: down and up. The down-drilling sequence is to first take the upper stage and then the lower stage, and to mine from top to bottom.
(2) The mining sequence of the nuggets in the stage
According to the positional relationship of the main development roadway (main well and main level), the mining order of the nuggets in the stage can be divided into three types:
(1) Forward mining, when the stage transportation roadway excavates a certain distance, it will pick up from the ore block near the main development roadway and advance to the boundary of the well field.
(2) Regressive mining refers to the stage transportation tunnels starting from the minefield boundary, starting from the miners at the minefield boundary and returning in the direction of the main development lanes.
(3) Mixed mining, with advanced mining in the initial stage, after the stage transportation is completed, it will be changed to retreat mining, or it will be changed to forward and retreat while mining.
(3) Mining sequence of adjacent ore bodies
If a deposit has multiple ore bodies adjacent to each other, mining one of the ore bodies will affect the adjacent ore body. At this time, the mining order of each ore body is reasonably determined, which is of great significance for safe production and resource recovery. The mining sequence is as follows:
(1) When the inclination of the ore body is less than or equal to the angle of collapse of the surrounding rock, the mining sequence from the upper plate to the lower plate shall be adopted.
(2) When the ore body inclination angle is larger than the surrounding rock caving angle, when the two ore bodies are close together, no matter which ore body is first taken, it will affect each other due to the surrounding rock movement of the goaf. At this time, the mining order of adjacent ore bodies should be determined according to the thickness of the stone layer between the ore bodies, the stability of the ore and surrounding rock, and the selected mining methods and technical measures. Generally, the ore body is first collected after the mining body is taken. If the thickness of the stone layer is not large, the mining order from the lower plate to the upper plate may also be adopted when the filling method or the retention method is used.
Fourth, the mining steps of the deposit
Step metal deposits underground mining can be divided into exploration, mining standards, cutting and stoping four steps, each step reflects the different stages of work.
(1) Pioneering work
Pioneering work refers to the excavation of a series of roadways from the ground to the deposit, so that the ore body is connected to the ground, forming a system of pedestrian, transportation, ventilation, drainage, power supply, air supply, water supply and so on. The purpose of the development is to transport the ore and waste rock to be collected to the ground, while discharging the waste water and dirty air to the surface, transporting personnel, materials and equipment to the underground. The roadway for this purpose is called development. Roadway.
(2) Approved work
Approving work refers to digging into the mining lanes in the developed mines, dividing the stages into ore blocks as independent units for mining, and creating conditions such as pedestrians, rock drilling, ore-laying and ventilation in the ore blocks.
(3) Cutting work
Cutting work refers to the opening of free surface and free space for large-scale mining of ore in the approved ore. To this end, it is necessary to dig into the bottoming roadway and open the bottoming space, or to dig into the cutting lane and the cutting patio and form the cutting space (cutting groove), and some also expand the funnel neck into a funnel shape, which is called leakage. Create good blasting and ore-mining conditions for large-scale mining in the future. Pulling lanes, cutting lanes and cutting patios are generally referred to as cutting lanes. Excavation of cutting roadways and projects such as pulling bottoms, cutting grooves and leaking are collectively referred to as cutting work.
(4) Mining work
After the cutting work is completed, a large amount of mining can be carried out (sometimes cutting work and mining simultaneously), often referred to as mining work. It includes three main operations: mining, handling and ground pressure management.
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