What types of ventilation systems are there?

The ventilation system can be divided into three types according to the position of the inlet and outlet shafts: central, diagonal and hybrid.

Central type

The location of the inlet and outlet wells is roughly at the center of the field, and there are only two wellbores (or flats) that reach the surface, as shown in Figure 1. This method is mostly used in mines with deep burial, and it is rarely used in mines in China.

Figure 1 Schematic diagram of the central ventilation system

Diagonal

The inlet and outlet shafts are respectively located at the center of the ore body and the boundary of the ore body. Diagonal ventilation is divided into two wings and one wing. The two-wing ventilation system has three wells that reach the surface, one of which is the inlet well and the other two are the outlet wells, as shown in Figure 2. The single-wing ventilation system is that the ventilation shaft and the outlet shaft are respectively located at the two ends of the ore body, as shown in Fig. 3. Such ventilation in the mine of the metal used widely.

Figure 2 Schematic diagram of two-wing ventilation system

Figure 3 Schematic diagram of a single-wing ventilation system

mixed type

The inlet and outlet shafts are composed of more than three wellbores and are arranged in a central and diagonal manner. This kind of ventilation system is rarely used in metal mines in China.

According to the working mode of the fan, it can be divided into three types: press-in type, draw-out type and pressure-pump type.

Press-in ventilation is the positive pressure of the entire ventilation system under the action of the push-in main fan, which is higher than the local atmospheric pressure. The advantage of press-in ventilation is that the wind flow is concentrated, the air volume is large, and the wind quality is good, so that fresh airflow can quickly enter the well. The shortcoming is that the wind leakage at the bottom of the well is large; the ventilation structure is not easy to manage and control in the inlet section, and the dirty wind can not be discharged according to the designated line, which is easy to cause wind flow disorder.

Withdraw ventilation is to make the whole ventilation system under the action of the extraction main fan, forming a negative pressure state lower than the local atmospheric pressure. The extraction type ventilation and exhaust air is concentrated, the exhaust air volume is large, the sewage wind discharge speed is fast, and the wind flow adjustment control facility setting control is convenient and effective. The disadvantage is that when the exhaust system is not tight, it is easy to cause short-circuit suction, and the extraction ventilation makes the main lifting well in the air inlet position, and the anti-freezing problem should be considered in winter. Exhaust ventilation is the application of more ventilation of other non-metallic mineral and coal mining.

Press-pull hybrid ventilation is controlled by the main fan for both intake and exhaust. The advantage is that the wind flow can be flowed according to the line, the smoke exhaust method is faster, and the air leakage is less. The disadvantage is that the demand for the ventilation equipment is increased, and the wind flow of the wind-receiving section cannot be controlled, and the air leakage of the wind-side side bottom yard and the exhaust side collapse area Still exists, there are currently not many applications.

Screw Conveyor

The screw conveyor is a new type of transport equipment which continuously pushes materials by rotating screw blades in a closed shell with circular cross-section.