Abstract: In order to compare the fire extinguishing performance difference of foam fire extinguishing agents and water-based fire extinguishing agents on fighting mesoscale typical oil fire and large petrochemical storage tank fire, choose aqueous film-forming foam extinguishing agents and water based extinguishing agents, especially "new" water based extinguishing agents, built mesoscale fire model and simulate large petrochemical tank fire model to carry out the experimental study. By comparing 50% fire control time, 90% fire control time, extinction time and 25% burn-back time and the change of fuel surface temperature in the fire extinguishing process, the fire extinguishing performance of the above two water-based fire extinguishing agents is obtained. The research results show that the performance parameters of the aqueous film-forming foam extinguishing agents, including the expansion, 25% drainage time, fire control time, extinction time, especially 25% burn-back time are better than that of the water based extinguishing agent in mesoscale typical oil fire. In the fire fighting of simulated petrochemical storage tank fire, the fire control time and extinction time of the aqueous film-forming foam extinguishing agent are obviously better than that of water based extinguishing agent, which makes its fire extinguishing efficiency much higher than that of water based extinguishing agent. Therefore, it is suggested that foam extinguishing agent should be selected for large oil fires, especially petrochemical fires.

Key words: foam extinguishing agent, water based extinguishing agent, typical oil fire, oil storage tank fire, extinction time