大流量液氮泡沫灭火装备在化工园区的应用研究

介绍了液氮泡沫灭火技术原理，研究了液氮泡沫发泡倍数、析液时间、微观状态等，搭建了泡沫长距离输送管路系统，研究了液氮泡沫的长距离输送性能，通过多尺度储罐灭火实验验证了液氮泡沫灭火能力。实验表明：液氮泡沫的气泡直径在20~50 μm，气泡直径相对均匀；发泡倍数在7~8，25%析液时间在3~5 min。液氮泡沫可在消防带内输送1 000 m，无析出分层，泡沫性能保持不变。液氮泡沫较压缩空气泡沫的灭火能力提升1.6倍以上，较吸气式泡沫的灭火能力提升2.5倍以上。该大流量液氮泡沫灭火系统可用于扑救大型储罐火灾、地面池火、流淌火及大型生产装置立体火灾等。

Research on the application of large flow liquid nitrogen foam fire extinguishing system at chemical parks

The mechanism of liquid nitrogen foam fire extinguishing system was introduced and foam expansion, drainage time, micro image of liquid nitrogen foam were studied. Long distance pipe system was established to study the transportation of liquid nitrogen foam. Multi-scale tank fire tests were conducted to test the fire extinguishment of the foam. The results showed that the even diameter of liquid nitrogen foam bubbles was 20 ~ 50 μm and the foam bubbles were even. Foam expansion was about 7 to 8 and the 25% drainage time was about 3 to 5 minutes. The liquid nitrogen foam can be transported to 1 000 meters without foam layer drainage, and the performance of the foam remains the same. The fire extinguishment capability of liquid nitrogen foam was about 1.6 times of that of compressed air foam and 2.5 times of that of aspirating foam. The large flow liquid nitrogen foam system can be widely applied for large tank fires, floor pool fires, flowing fires and some large equipment fires.