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In view of problem that most of existing oxygen supply systems of refuge chamber applied multistage protection system, and oxygen supply subsystems are independent of each other and cannot automatically switch among them, which causes the oxygen supply unstable, an automatic oxygen supply system of refuge chamber based on PLC and PID monitoring technology was designed. The system integrates multistage oxygen supply systems and environment parameters monitoring system through loop optical fiber system. Based on the detected environment parameters in real-time, and uses PLC and PID monitoring technology, the system can realize intelligent adjustment between all levels of oxygen supply system and automatic continuous supply oxygen of underground refuge chamber, and can automatically switch to the next level of oxygen supply system when a certain level of oxygen supply system happens failure, which improves stability and safety of the oxygen supply of refuge chamber. The site test results verify reliability of the system.

Relationship formula between average concentration of harmful gas and pressure ventilation supply volume in refuge chamber was given, CO2 concentration distribution in refuge chamber under conditions of different pressure ventilation supply volume and air outlet layout were analyzed through refuge experiment with 50 people. The experimental results show that when air supply volume per person is 84 L/min, CO2 volume fraction in refuge chamber could be controlled under 1%; CO2 concentration distribution is uneven when only one air outlet is set in refuge chamber, air outlets should be evenly arranged in both sides of long passage of refuge chamber, and CO2 concentration distribution is more even with more air outlets.

The paper analyzed special pipeline technology for emergency refuge, and pointed out that “six systems” with the special pipeline for underground safe refuge can improve anti-disaster ability of pipeline, but the underground safe refuge system derived from the special pipeline cannot replace coal mine communication system, monitoring and control system and personnel positioning system, and it cannot perceive disasters. It compared and analyzed technical characteristics of life-saving shelter and refuge chamber, pointed out that the life-saving shelter has shortcomings of being susceptible by disaster, needs cooling and high cost. It put forward that coal mine should be equipped with high-power submersible pump, and should be careful to use rescue equipments of flood drilling. It proposed area captain and group leaders should be part-time draegerman. It also proposed that hand-over works should try to be completed on the ground, so as to reduce underground personnel.