What Causes Grain Elevator Explosions
Around the holidays I heard there was a explosion and fire at the Northrup Grain Elevator in Martin County. I had a pretty good idea the explosion was caused by grain dust so I called Bob Zelenka, Executive Director of the Minnesota Grain and Feed Association. Zelenla said that grain dust was more than likely the cause of the explosion and fire. "Back in the day" elevator explosions and fires were much more common than today. Many of these older wood grain elevators are no longer being used and the newer ones are much safer
I knew grain dust was explosive but did not know how explosive it really was. In addition I thought soybean dust was the most dangerous. However, Zelenka said corn dust is more explosive. In fact, corn dust is more explosive than gun powder. If you have an area with a lot of corn dust, all you need is some type of ignition source. It does not even need to be an open flame. If a bearing in a grain leg goes out the metal can get red hot and spark an explosion
Newer elevators are designed with the idea of controlling grain dust in mind. In addition there was an OSHA and Pollution Control Agency requirement that grain elevators with more than 2.5 million bushel storage capacity have a dust control system. That regulation went into affect back in 1988. I saw the system in action when I toured the new Crystal Valley shuttle loading elevator at Hope. The fans suck air from the dump pit and collect it in a tower for disposal. There was no grain dust by the dump pit.
You may be wondering about the grain that was in the elevator that exploded and burned. Who is responsible for the grain that was lost or destroyed? One of the requirements of being a commercial elevator is that elevator owners have insurance. State and Federal regulators do inspect and make sure an elevator does have insurance to cover losses like this. So, an insurance claim will be filed.