A Literature Review on Railroad Tank Car Thermal Protection Systems

Abstract

Abstract Railroad tank car transportation is the most efficient way to transport large amounts of hazardous material. More than 2 million tank-car loads of hazardous materials (hazmat) are transported annually by rail in the United States. Recently, the boom in the production of petroleum crude oil and natural gases from shale has dramatically increased the rail transport volume of flammable energy resources. However, accidents do occur, and the transportation of flammable hazardous material can result in disastrous consequences. The fire can heat up a tank car, rapidly increasing the inside pressure and causing the tank car to either rupture or explode. Railroad companies are developing or seeking advanced thermal protection systems to prevent tank car explosion or prolong the burst time to win a sufficient rescue time. It is of great importance to understand the existing thermal protection systems used in hazmat tank cars and to identify key priorities that the government and industry consider for improving tank car thermal protection performance, providing guidance for future thermal protection material development. Thus, this paper reviews the literature on the effects and analysis of different tank car thermal protection systems, identifying the effectiveness of different thermal protection components, properties of thermal protection materials, and testing methodologies. Different combinations of insulators and jackets are tested in order to observe the effects of the fire on the tank car. The tank car is tested while carrying hazardous material like liquefied petroleum gas, propane, and ethylene oxide, etc. This investigation analyzes the differences of thermal protection systems in prolonging the life span of a tank car engulfed in flames. A tank car can use either material like fiberglass, ceramic fiber blankets, perlite powder, or urethane foam to better insulate and thermally protect the tank car. An insulator is shown to prolong the life span of a tank car since bare tank cars tend to heat up rapidly when exposed to flames. The thermal protection system of a tank car is built of insulators, jackets, and supporting material for the insulator. The supporting material and jacket combination with the insulator also prevent the tank car from heating up rapidly. There are two primary testing methods, pool fire, and torch fire. Each type of fire has different outcomes and limits in which the tank car can withstand. When testing the heating of a tank car, thermocouples were placed throughout a tank car and recorded to check what areas were heated the most during the experiment. Some factors that had been accounted for in the previous studies were the wind speed and the direction of the wind, which affected the overall experiment, mostly torch fire experiments.