ES369495A1 - Process for quenching flames and extinguishing fires and devices therefor - Google Patents

Abstract

Fires are extinguished by ejecting on to the fire symmetrical dibromotetrafluoroethane under a pressure of from 4 to 20 atmospheres through a spray nozzle having an internal bore substantially in the shape of a truncated cone with a conical angle from 4 to 20 the cone converging in the direction towards the outlet orifice of the nozzle. (The "conical angle" is one-half the flare angle of the cone.) The outlet orifice may be circular, or elliptical in which the ratio of the major axis to the minor axis of the ellipse is between 5:1 and 1:1. The dibromotetrafluoroethane may be pressurized by a mechanical pump or through the use of a gaseous propellant, exemplified by: (1) nitrogen, helium or air (insoluble in the dibromotetrafluoroethane) (2) carbon dioxide (partially soluble) and (3) halogenated hydrocarbons such as CF 2 Cl 2 , CHClF 2 , CBrF 3 or CF 4 (completely soluble). According to one of many examples, 180 Kg of dibromotetrafluoroethane was loaded into a 100 litre tank of a wheeled extinguisher and this was then pressurized at room temperature with nitrogen. The combustion of a benzene - gas oil mixture was extinguished by the ejection of about 1 kg of the dibromotetrafluoroethane through a nozzle having an orifice of elliptical shape and a conicity of 8 and 6 . The area of the orifice surface amounted to 20 mm2 and the ratio of the major/minor half axes was 3:2. Other combustible materials are detailed.