DESIGN AND CALCULATION SPECIFICS OF THE SUBSURFACE FIRE EXTINGUISHING SYSTEM

Introduction Despite the significant progress in technology, including the field of fire safety, fires of oil and petroleum products tanks remains one of the most difficult ones to extinguish. This type of deflagration develops rapidly, has protracted nature and requires the involvement of a large number of means and forces. Also, such fires cause enormous material and environmental damage and pose a significant danger to people's life and health. One of the safest ways to extinguish fires in oil and petroleum products tanks is a subsurface fire extinguishing method. This method uses foam concentrate with fluorinated stabilizers, an aqueous solution of which can cover the surface of petroleum products with a thin film. At the moment, this issue is not researched well enough in our country. The official Ukrainian regulation documents describe technical parameters of oil tanks extinguishing system, but the method described in these documents is the same for both subsurface fire extinguishing and surface foam supply. Therefore, a specific methodology for calculating the main parameters of the subsurface tank extinguishing system is necessary. Purpose The purpose of this study is to describe the methodology for calculating the main parameters of the subsurface tank extinguishing system. Calculation of the different technical parameters of the subsurface method-based extinguishing system depending on the tanks type, fuel types, concentrations of foaming agent, etc. is provided. Results This research outlines the main problems of fire extinguishing in tanks with oil and petroleum products, and specifics of their elimination by supplying fluorosynthetic foaming agents into the layer of combustible material. The research also describes calculation methods of the main parameters of the subsurface fire extinguishing method for extinguishing fires in oil and petroleum tanks using low expansion foam. Examples of calculation using tank RVS-10000 for both proposed methodology and methodology described in the official Ukrainian regulation documents are provided. Various technical parameters of the subsurface method-based extinguishing system were calculated depending on the tanks type, fuel types, concentrations of foaming agent, etc. Conclusion The results of this research prove that spendings on foam agents and damages from the oil fire can be reduced when using subsurface fire extinguishing method.