INFLUENCE THERMAL INSULATION OF POLYURETHANE FOAM, APPLIED WITH THE INSIDE WALL OF THE VERTICAL STEEL TANK, ON THE TEMPERATURES WALL IN BURNING

The article determines that the heat insulation of the tanks maintains specified temperature of petroleum products. The effective normative documents limit the use of the polyurethane foam, which is caused by their high fire hazard. The regulatory document defining the terms of use of materials is “Technical regulations for fire safety requirements”. The essence of the method of defining the materials by their combustibility consists in holding of a cylindrical sample of the material in the furnace. The operating conditions of the material are not taken into account in this case. Quite often, through the leakage of connections the external non-combustible thermal insulation gets impregnated with oil or oil products, and this creates the conditions conducive to spontaneous ignition and (or) flame spreading on the insulation surface. Thus, the use limitation of the combustible heat insulation without taking measures to prevent the «oiling» effect of the non-combustible thermal insulation is inefficient. In the article it is suggested the usage of the polyurethane foam on the inner surface of the tank wall for its thermal insulation. There were conducted a number of experiments with regard for the operating conditions of the tank. The results of the experiments made it possible to define the positive effects of the proposed method of the thermal insulation method, such as: 1) decrease of the inconsiderable reservoir breathing while the tank is in operation, which leads to the increase of economic and environmental efficiency of the thermal insulation; 2) reduction of the fire hazard of the insulation in comparison with the external method of heat insulation, which is caused by the lack of the combustible materials on the outer wall of the PBC and, as a result, by the lack of the “oiling” effect of the heat insulation; 3) reduction of the corrosive wear of the tank; 4) increase of the technological oil pumping speed; 5) increase of the fire resistance limit of the tank wall by the fire; 6) maintenance of the cooling possibility of the tanks during the fire by stationary plants and mobile fire equipment which is generally not possible on application of traditional methods of the heat insulation of the tank walls with the help of non-combustible materials from the outside.