Ammonium nitrate (AN) is widely used as a nitrogen fertiliser and as an additive when manufacturing explosives. It can be found naturally as a mineral and is produced by reacting anhydrous ammonia with nitric acid and dried to form small beads/prills.
While extremely stable under most conditions, this widely used fertiliser is also commonly stored in bulk quantities posing a risk if not properly protected against large fires. Despite knowing such risks, ammonium nitrate explosions have continued to occur in recent years.
In 2020, in Beirut, Lebanon, 2,750 tons of ammonium nitrate were stored unsafely in a warehouse. A fire broke out in the warehouse and started a series of events that led to the detonation of the hazardously stored ammonium nitrate. The city of Beirut was shaken by the detonation and severe damage was observed throughout the city.
Dreadfully, this incident has similarities to the Tianjin explosion in China which occurred in August 2015, and the explosion in West, Texas in the USA, in April 2013.
All these events involved the “unique” set of conditions necessary to turn the relatively stable oxidiser Ammonium Nitrate into a detonating explosive.
Ammonium nitrate related incidents in China, Unites States, and Lebanon.
Source: YouTube
Advanced blast techniques were used to determine the quantity of ammonium nitrate that likely detonated during each of these blasts. These techniques included near-field blast effects (e.g., the resulting crater left by the blast) as well as the far-field blast damage resulting in the neighbouring community.
Results showed that the detonation of ammonium nitrate in Lebanon was the largest of the three in terms of blast damage approaching levels up to 1,000 tons of TNT, whereas Tianjin was estimated to be equivalent to approximately 300 tons of TNT.
During the 2022 Spring Meeting and 18th Global Congress on Process Safety, Gexcon US CEO & Principal Engineer Scott G. Davis, Ph.D., P.E., CFEI will present a paper entitled “Why Do Devastating Ammonium Nitrate Detonations Still Occur: Lesson Still Not Learned in Beirut, Tianjin, and West Texas”.
Dr. Davis will discuss ammonium nitrate incidents in Beirut, Tianjin, and West Texas, as well as lessons learned to avoid such incidents in the future.
He will explain the unique set of conditions necessary for the explosive decomposition of ammonium nitrate and ways to prevent and mitigate the detonations.
He will also discuss how advanced blast techniques can help in understanding the consequences of ammonium nitrate explosion.
Presentation detail
Title: Why Do Devastating Ammonium Nitrate Detonations Still Occur: Lesson Still Not Learned in Beirut, Tianjin and West Texas
Author: Scott G. Davis, Tom De Bold, and John Pagliaro
Session: GCPS Joint Session: Case Histories and Lessons Learned
Presenter: Scott G. Davis
Date & Time: Wednesday, April 13, 2022 – 2:15 – 2:45 PM CDT
Webinar
Understand the unique set of conditions necessary for explosive decomposition of ammonium nitrate and how to prevent devastating ammonium nitrate explosions.
