Research on Design and Application of Fast Extinguishing Device of Rim Seal Fire for External Floating Roof Oil Tank

The loss of the circle of the outer floating roof oil tank wall or the loose sealing ring will cause the leakage of oil vapor and the risk of explosion and fire. Moreover, the sealing ring fire has become the main fire type of the outer floating roof oil tank.The fixed fire extinguishing system in the storage tank area in China can be divided into floating disc type and tank wall type. Through investigation, it is found that these two kinds of commonly used fixed fire extinguishing facilities have the following shortcomings when extinguishing the sealing ring fire: for example, slow start and slow fire extinguishing; negative pressure foaming, easy to absorb a large number of high temperature oil vapor, affected by the liquid level, foam loss, etc. In view of this, this paper developed a rapid fire extinguishing device with sealing ring of external floating roof tank, which adopts positive pressure foam generator and nitrogen drive, and can be linked with fiber grating system to realize fast start fire extinguishing. The full-size sealing ring fire test shows that the modified device can quickly and efficiently extinguish the initial fire of the sealing ring, spray fire extinguishing agent directly to the flame root, and the foam does not need to be closed, so it can directly extinguish the fire, effectively shorten the extinguishing time, and has a good market application prospect.