The prior failure with the custom concrete containment vessel would have done the same thing but, as you mentioned, the containment vessel quickly clogged with methane hydrate crystals.
Funny how the containment vessel will ‘clog’ with methane hydrate crystals, but the well itself won’t.
pressure, it’s all about pressure
“Funny how the containment vessel will clog with methane hydrate crystals, but the well itself wont.”
The crystals form upon depressurization.
Same principle behind an airconditioner coil