Abstract:
In response to the problem that the uncontrollable spread of smoke flow during mine fires can lead to major accidents, and the difficulty in on-site emergency control and the lack of a coordinated smoke exhaust system, based on the evolution laws of fire smoke flow, the sensor placement positions were determined, and the principles, methods, control goals, and solution models for disaster smoke flow regulation were proposed. Taking the conveyor belt alley of Zhuanlongwan Coal Mine as an example, a model was established to simulate and analyze the laws of fire spread, smoke gas movement, CO and temperature field distribution, and determine the optimal sensor placement positions. A fire smoke flow emergency coordinated control model for the ventilation system of Zhuanlongwan Coal Mine was established, using the short-circuit smoke exhaust method to simulate and study the evolution laws of fire smoke flow in the horizontal II-3 conveyor belt alley and the western alley with or without wind control measures. The wind and smoke flow evolution characteristics and coordinated wind smoke flow control methods for different fire source positions were discussed, and a strategy for combining large and small fire prevention zones in the mine was proposed. Different fire smoke evolution simulation under different fire prevention zone modes was carried out and the control effect of wind smoke flow was compared, revealing the coordinated control mechanism of fire smoke flow in the complex ventilation network of the mine. The results show that wind speed has a significant impact on smoke gas movement. When the wind speed is between 2 m/s and 2.5 m/s, the backward flow of smoke disappears. When the wind speed is greater than 2.5 m/s, the high-temperature smoke gas no longer flows backward. At the beginning of the fire, a high-temperature area appears at the top of the alley. Sensors should be placed in multiple areas at the top of the alley according to the wind speed. If a fire starts at the rear of the horizontal conveyor belt alley, the smoke flow will spread to the rear end of the horizontal and the 232 mining area in 180 seconds. At 70 seconds, the smoke gas is introduced back into the return airway. If a fire starts in the middle rear of the western alley, the entire mining area is invaded by high-temperature smoke gas at
1500 seconds. At 70 seconds, the smoke gas is introduced into the western return airway. The Zhuanlongwan mine was divided into 4 large fire prevention zones and 9 small fire prevention zones. Network calculation was carried out during the disaster period, proving that the divided fire prevention zones can effectively control the fire smoke flow and meet the ventilation requirements of key alleys. Based on precise sensor perception, an intelligent emergency coordinated control system for mine fire smoke flow was developed, integrating backup power supply and pressurized air power, ensuring the automatic control of wind doors (windows) under disaster power outage and damage to pressurized air power, achieving coordinated control of the wind and smoke flow in the network, and creating safe conditions for the escape of underground personnel and the emergency handling of disaster situations.