nsuring the safety and energy efficiency of ventilation of shafts and mines that use the air recycling system

Abstract

The paper describes the possible failures in the automation ventilation system with partial return use of upcast air from a shaft or mine (during recirculation). Existing ventilation systems use recirculation in the main ventilation mining, through which air is delivered from an underground mining enterprise. It is proposed to install automatic ventilation doors (AVD). They allow to change the aerodynamic resistance of the mine, i.e. control flow rate of air discharged from a mine (shaft). If an AVD is damaged the dangerous case could arise even in a normal ventilation mode due to the fact that mentioned negative control means can block the main path of air movement. In this case air from the air-supplying barrels is directed to the ventilation barrel through the recirculation loop bypassing the mining sites dedicated for ventilation. At the time of accident, when the main fan unit (MFU) is reversed, such a failure makes the situation even more dangerous due to the unpredictable path of flue gases. In the method described it is proposed to install the AVD in the mines of the main directions and close them only during the period of the MFU reverse. When the closing AVD and forced draft fan of the main air heater work together and discharge air in the reverse mode, the time dedicated for switching of the main heater to the reverse mode is reduced. After the gradual opening of the AVD in the shaft (mine) a reversible mode of ventilation is installed. The method proposed allows energy and resource savings for ventilation and air preparation both in normal and emergency modes while meeting the safety requirements for mining operations.

Keywords

• recirculation
• main ventilation unit
• air stream reverse
• mining safety
• energy saving