Holistic Case Study on the Explosion of Ammonium Nitrate in Tianjin Port

Abstract

On 12 August 2015, Tianjin port, Tianjin City, China, a catastrophic explosion of Ruihai International Logistics Co., Ltd. (Tianjin, China) killed 173 and hurt almost 798 people, accompanying a financial loss of almost USD 2 billion. The ignition of the first fire due to the autocatalytic decomposition of nitrocellulose was verified by differential scanning calorimeter (DSC) isothermal tests. A crater with a diameter of 97 m was created by the second explosion. For the second catastrophic explosion, an amount of 577 tons of trinitrotoluene was determined by the average through scaling law, crater inverse analysis and blast effects on structures. The overpressure against distance for consequence analysis was conducted using Baker’s, Sadovski’s and Alonso’s methodologies. A distinctive scenario of “two-successive-sympathetic detonations-following-a-fire” was proposed and discussed. Isothermal time-to-maximum-rate was validated to be approximately 9 days for the nitrocellulose inside the containers with an internal temperature of 60 °C stored at Tianjin port. A fatality radius chosen at the overpressure of 0.6 bar was ascertained to be nearly 410 m from the explosion origin.