Using air-filled foam to contain and liquidate the flaming combustion of liquefied natural gas spills

Introduction. Using air-filled foam to contain and liquidate the flaming combustion of liquefied natural gas spills is one of the most optimal methods of preventing the escalation of emergencies. However, the amount of data available today is insufficient to standardize the basic parameters of air-filled foam injection. The purpose of this research project is to justify the application of air-filled foam to contain and liquidate the flaming combustion of liquefied natural gas and identify the basic parameters of injection. The following objectives are to be attained towards this end: assessment of the fire and explosion safety of liquefied natural gas and analysis of extinguishing means applicable to spills; experimental determination of the insulating ability of foams, having different expansion factors, if applied to the surface of cryogenic fluid; experimental determination of the fire-fighting efficiency of the foam used to liquidate the flaming combustion of liquefied natural gas; experimental verification of expediency of the joint application of high expansion air-filled foam and extinguishing powders. Results and discussion. Having discussed the findings of the in-house experiments and analyzed the international and domestic tests conducted for this purpose, the authors assume that the application of the foam, whose expansion factor equals 300 to 500 units, can effectively contain and liquidate the flaming combustion of liquefied natural gas. The flaming combustion cannot be liquidated, if lower expansion factor foams are applied. The application rate of the high-expansion air-filled foam, exceeding 0.08 kg/(m2·s), is required to reduce the intensity of flaming combustion. Flaming combustion can be efficiently liquidated if the application rate of high-expansion air-filled foam is set at 0.17 ± 0.01 kg/(m2·s). Fire-extinguishing powders can only be efficiently applied to liquidate the flaming combustion of liquefied natural gas, if its surface is covered in foam. Conclusions. The authors have used their in-house experimental data, analyzed the literary sources and wellknown properties of the fire-extinguishing foam to justify the basic parameters of foam application aimed at the containment and liquidation of the flaming combustion of liquefied natural gas.