Exploding Flour Mills.

[coldfeet]

Why is flour so explosive? (this applies to all explosive fine powders) We've been debating all evening.. probably very simple but we're not scientists I'm afraid!

[Buenchico]

There's some basic information here:
http://home.howstuffworks.com/question150.htm

For more detailed information, follow the 'Grain Dust Peril' link from that site.

Chris

[gammaray]

They are not inherantly explosive, just that a fine (combustable) powder has a low flash point and burns very quickly. In a confined space this creates an explosive reaction as the pressure builds up behind the burn.

[stevie21]

With powder *that* fine, the surface area will be larger than, e.g. something like small seeds so there's more surface for chemical reactions to take place on, hence the combustion is faster.

[coldfeet]

Super. We were almost there with our theories but that helps a lot, thank you!

[woofgang]

here's a good explanation...the powder here is custard, bu the theory is the same

http://www.interactives.co.uk/hearts_custard_transcript.htm