@Smokin Joe
Just guessing,but my GUESS is a leaky Propane tank.
Someone on the twitter feed mentioned a Methane digester (for processing manure) as a possibility.
Propane tanks don't usually explode, they will leak, the leak ignite, and the tank rupture when the pressure relief valve can't keep up with the pressure (which looks a lot like an explosion, and can have that sort of force) but you'd think someone would have noticed that, or if it was leaking and pooling in the facility (propane is heavier than air), they should have picked up on the mercaptans in the propane (the stink that gets added in).
According to these guys,
https://texags.com/forums/16/topics/3372543/1 The facility was pretty well enclosed, and a vacuum pump that was supposed to remove methane from the building may have failed. The buildup was ignited, somehow, and boom. That seems to be one theory, the other is that there was an ignition source in proximity to the methane digester, which would not take much to ignite, again, with catastrophic results.
There are a couple of fairly graphic descriptions of the damage to the cattle in there, so not for the squeamish.
