Experimental evaluation and analysis of methane fire and explosion mitigation using isolation valves integrated with...

Area of Science:

• Industrial safety
• Combustion science
• Mechanical engineering

Background:

• Extractive industries face risks from flame deflagration.
• Mechanical mitigation systems offer potential safety solutions.
• Verification of passive and active systems is crucial for implementation.

Purpose of the Study:

• To experimentally investigate the performance of passive and active mitigation valves.
• To assess the effectiveness of mechanical means in controlling flame deflagration.
• To analyze pressure wave generation and flame propagation with different mitigation strategies.

Main Methods:

• Experiments were conducted in a large-scale detonation tube (30m x 0.5m).
• Methane concentrations ranged from 1.25% to 7.5%.
• Passive and active mitigation valves, along with a burst panel venting system, were utilized.

Main Results:

• The passive valve at 22m fully isolated the flame but generated a secondary upstream pressure wave.
• The active mitigation system achieved complete upstream-downstream isolation without generating new pressure waves.
• Vent placement at 6.5m reduced total pressure by 0.48bar, and flame extinction occurred at 12.5m.

Conclusions:

• Active mechanical mitigation systems are superior to passive systems for controlling flame deflagration.
• Active systems prevent secondary pressure wave generation, enhancing safety.
• Strategic vent placement and active valve operation can effectively extinguish flames and reduce explosion pressures.