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First, partition ventilation
According to the characteristics of the mine, a mine is divided into several independent ventilation areas for ventilation, called zone ventilation.
(1) Applicable conditions for district ventilation
1. The ore body is buried shallowly and is relatively scattered. The amount of ventilation engineering for accessing the surface is small, or there are ready-made wells available for use.
2. The ore body is shallowly buried, long in length and large in output. If a ventilation system is formed, the wind path is too long, the air leakage is large, the network is complicated, and the air volume adjustment is difficult.
3. Mining a surrounding rock or ore with a natural fire hazard and a large scale mine.
(2) The principle of division of district ventilation
Each ventilation system of the district ventilation has its own ventilation power and a complete inlet and outlet shaft, and their ventilation systems are independent of each other. To implement district ventilation, it is necessary to divide the ventilation area reasonably to prevent the airflow from interfering with each other between the ventilation systems in each area. The division of the ventilation area should be based on the burial conditions of the ore body and the specific conditions of the mining. The general principle is: the concentration of the ore is relatively concentrated, and the closely related parts of the production are zoned in a ventilated area.
1, divided by the middle
If the ore body is above the erosion reference plane, and each middle section has several independent outlets that pass through the surface, the entry of fresh air and the collection of dirty winds in the middle sections of the middle section can be via the middle section, and there is little connection between the middle sections. Under these conditions, the ventilation system can be divided by the middle section.
2, according to the ore body
If the ore body is dispersed, the ore bodies or groups of ore bodies are transported out through the wells of the system, and the pedestrian system, material transportation, production management, etc. are all self-contained, and the ventilation system can be divided according to the ore body.
3. Divided by mining area
When the mine has a wide range and is divided into several mining areas for production, except for the ore being transported out through uniform wells, the pedestrian, material transportation and production management are all self-contained. In this case, The mining area is used to divide the ventilation system.
4. Divided by mechanical ventilation zone and natural ventilation zone
When some of the production mines are close to the surface of the shallow ore body, and a large number of goafs and old lanes are connected to the ground. If it is difficult to incorporate the main fan ventilation system, the part can be removed from the main fan ventilation system. Isolated in the middle, forming a natural ventilation zone alone (sometimes temporary temporary auxiliary fans to enhance ventilation). In doing so, not only the shallow ore body forms a certain airflow system, but also the deep main fan ventilation system is more perfect.
(3) Characteristics of district ventilation
The network is simple, the wind flow is easy to control, the connection opportunities are few, the wind path is short, the ventilation resistance is small, the wind pressure loss is small, and the air leakage is small. When the low-pressure small fan is used or the fan is installed in the well near the working surface, the effect is better. Low ventilation power consumption; medium and small ventilation equipment, fast production, capital investment investment, is conducive to installation in high mountains or underground, fresh air can be quickly delivered to the working surface, and can reduce pollution along the way, the ventilation system is flexible and easy to adapt The situation of changing working faces. However, district ventilation requires more wind shafts. If there are no ready-made tunnels available, infrastructure investment will be increased, main fans will be dispersed, and management will be inconvenient. Under the existing conditions of metal mines, ventilation partition shows a lot of advantages, especially for Jiangxi, Hunan, Guangdong, tungsten ore system, gold mines and similar small and medium sized mines, has more obvious advantages.
  Second, ventilation network
The so-called ventilation network is the structure formed by the interconnection of the air ducts. The basic form of ventilation network is parallel, series and angular. However, the actual mine ventilation network is extremely complicated, and there are two types of mine ventilation network and mining area ventilation network.
Typical mine ventilation networks are as follows:
(1) Checkerboard ventilation network
In the mine, along the ore body, a return air courtyard that connects the upper and lower middle sections and reaches the upper total return air passage is reserved at a certain distance. The intersection of the patio and the transportation lane is crossed by the wind bridge. In this way, several sets of parallel wind nets are formed, and the dirty wind of the working surface in each wind net is introduced into the return air patio through a total return air passage to discharge the surface in a certain manner. This kind of network can be used in a wide range, not only for the whole mine ventilation network, but also for the ventilation network of the mining area. For the parallel dense vein deposits, the same middle section can be used to follow the vertical veins and the Sichuan vein. The above principles constitute a level of checkerboard ventilation.
(2) Interval ventilation network
A return air duct is arranged in each middle section, and the upper working section of the middle section of the return air enters the wind from the upper middle section, and the wind flow descends. The working surface of the lower part of the middle section of the return air enters the wind from the lower middle section, and the wind flow rises. The waste wind in the middle part of each return air is discharged from the return air well at one end. This type of network is suitable for use in situations where it is not advisable to dig the return air patio and the working surface can be used for down ventilation.
(3) Stepped ventilation network
When the ore body is retracted from the side of the return air well to the air intake well, the transport tunnel of the upper middle section has been used as the return air passage of the lower middle section, so that the wind flow of each middle section is staggered in a stepwise manner. This type of ventilation network is suitable for retreat mining. This type of network can be combined with other network forms when the exploration and development of the middle section of the waste wind does not affect the upper middle section.
(4) Comb ventilation network
In each middle section, a dedicated vein-back air duct is established, and the cross-section of the tunnel is expanded to form two compartments with the wind, one for transportation and the other, and the other for returning to the wind. The return air path is connected with the returning air duct along the vein. The special return air passage in the middle section is like a comb handle. The windward air barrier is like a comb tooth, so it is called a comb network. This ventilation network is suitable for parallel dense vein deposits, and neither the Chuanmai nor the vein tunnels can be used for return air. 
Metal mine ventilation technology
Whether it is dust removal ventilation, ventilation of guns and diesel exhaust, anti-mite ventilation, ventilation technology occupy an important position.