[SunkenCiv]

http://www.bbc.com/news/world-asia-china-33844084

How did the blasts happen?

They took place at a warehouse at the port which was reportedly storing “dangerous and chemical goods”. The building is owned by Tianjin Dongjiang Port Ruihai International Logistics.

Ruihai Logistics was reportedly set up in 2011, and it handles about one million tonnes of cargo annually. Chinese media said that at least one member of Ruihai’s staff had been arrested.

Officials insist it is not yet clear what triggered the two blasts, about 30 seconds apart.

Before the explosions, many firefighters were already at the scene trying to control a blaze, AFP reports.

There have been suggestions that water sprayed on some of the chemicals could have led to the blasts.

Calcium carbide, known to be at the site, reacts with water to create the highly explosive acetylene.

[GeronL]

great idea to store that stuff in a warehouse in a crowded port city

[PA Engineer]

Officials insist it is not yet clear what triggered the two blasts, about 30 seconds apart.

There appears to have been three explosions. The last was probably an air fuel blast. The second explosion had the shock wave. It was reported that the third blast sucked air back into the fireball as evidenced by debris pulled back in.

I've been to a few gas explosions. Some of them very large. I have never seen such a large crater from a surface explosion. Something just doesn't seem right about this.

[outofsalt]

What industrial application is there for Sodium Cyanide? Why would one have tons of this stuff?