The Big Explosions of Ammonium Nitrate that Happened Since 1921

JAKARTA - Some speculations arose after the mushroom-like-explosion in Beirut, Lebanon. It was looked like an atomic or nuclear bomb explosion. However, based on the facts, the source of the explosion came from a warehouse that stored 2,750 tons of ammonium nitrate. It is known, large explosions due to these chemical compounds have occurred a lot since 1921.

Jeffrey Lewis, an expert professor of weapons controls at the Middlebury Institute of International Studies at Monterey, tries to analyze what caused the massive explosion at the port of Beirut that killed at least 63 people and injured thousands of others on Tuesday. Several things can be deduced from the Beirut explosion video that was widely circulated. Including before the larger explosion occurred.

Lewis said the trigger for the explosion was possible when the ammunition in the warehouse caught fire. According to him, the rising smoke was then interspersed with sparks similar to fireworks. "The effect of small ammunition - such as rockets - burning," he told The Washington Post.

Then, there was an explosion of fiery fireballs.  After that, a powerful explosion that caused a mushroom-shaped cloud occurred. According to Lewis, the clouds are pressure from shock waves that condense moisture in the air.

This was affirmed by the Lebanese Minister of Home Affairs, Mohammed Fahmi. He said that the stock of ammonium nitrate - a fertilizer that could be used for making bombs - had exploded.

According to Lewis, the characteristics of the explosive ammonium are visible from reddish-brown smoke. The color comes from nitrogen oxides, a byproduct.

The big bang caused by ammonium nitrate is not the first time. Major disasters have even occurred in 1921.

The Oppau explosion in Germany

On September 21, 1921, a German chemical plant, BASF in Oppau - now Ludwigshafen - exploded. It stored about 450 tons of a mixture of ammonium nitrate and ammonium sulfate. According to the National Library of Australia archives, the disaster killed at least 500 to 600 people.

No one knows for sure the cause of the explosion. But, there is one strong possibility.

The incident allegedly occurred during an ammonia-making process known as the Haber process. When compared with ammonium sulfate, ammonium nitrate is very hygroscopic. It is very easy to absorb liquid. So, the mixture of these two compounds can harden.

The workers had to manually remove the "waste" of production from the storage area, which is called a silo. However, this method is quite risky for workers. There is a safer way to use small explosive dynamite to break down the mixture.

Starting with just the right mix, the dynamite won't set off another explosion. Unfortunately, on September 21, 1921, the disaster occurred.

The explosion that occurred at 7:32 in the morning made a 90-meter hole, with a width of 125 meters and a depth of 19 meters. The explosion was heard in France and the City of Munich.

The energy of the explosion is estimated at 1-2 kilotons which killed nearly 600 people.  Meanwhile, the material loss caused by this disaster was around US$ 7 million.

The PEPCON Explosion in the US

The catastrophic explosion of an ammonia compound also occurred in Nevada, United States. Precisely on May 4, 1988.

At that time, a large fire followed by several explosions broke out at the chemical plant Pacific Engineering and Production Company of Nevada (PEPCON). According to the Sandia National Laboratory report, the US Department of Energy in November 1988, the disaster left two people died while 372 were injured, and caused material losses of USD 100 million. The explosion reached up to a radius of 16 km from factories around the Las Vegas Valley.

According to a report by the US Department of Labor (USDOL) and the Division of Occupational Safety and Health (DOSH), the fire emerged around the plant's drying process installation.  USDOL reports that at least one fire burned in a barrel located on the southwestern side of the building partition, which separates the batch dryer from the batch tank in the process building.

Fires were also reported on the north wall of the batch dryer during the construction process. At that time, a worker was repairing a steel frame using a welding torch.

This activity causes fires to spread and be accelerated by the residual ammonium perchlorate. It was estimated that the PEPCON factory stored ammonium perchlorate, which is produced for military weapons, as much as 4,500 metric tons.