4 ms·
Drill = spark = boom = nasty stuff all over surrounding area
by VTimofeenko 4mo ago
Drill = spark = boom = nasty stuff all over surrounding area
- deleted 4mo ago[deleted]
- lokar 4mo agoInert gas?
- keepamovin 4mo agoRighti didn’t realize It was explosive like that but it really is Flash point 2 °C (36 °F; 275 K) Autoignition temperature 435 °C (815 °F; 708 K) Explosive limits 1.7%-8.2% Drilling is too risky then. What about dumping liquid nitrogen on the thing until it’s doused?
- VTimofeenko 4mo agoQuick googling sez that liquid nitrogen might solidify the MMA inside, turning it into even more of a pressure cooker
- SoftTalker 4mo agoIt's possible to drill or cut without creating sparks. Just need to control the speed of the cutter. Besides, tanks like these have various portholes, valves and drains already. The article mentions an "inoperable valve" so maybe that's the problem but I'd be surprised if there were just one. They must have been getting the contents out of the tank and into the manufacturing process somehow.
- VTimofeenko 4mo agoIIUC, the stuff inside is polymerizing, turning into goop that gummed everything up. It was probably not goop when used for the original purpose
- ssl-3 4mo agoDoes this mean that we should shoot holes in it like cowboys to relieve pressure, or does that instead mean that we should not shoot holes in it like cowboys to relieve pressure? (Because, I mean: If this thing is as sketchy as it is made out to be, then nobody is just walking over there with a spanner to loosen a cover. There aren't enough dollars nor PPE available to make this happen.)
- VTimofeenko 4mo agoShooting holes in pressurized vessels with explosive stuff is probably a very bad idea, as outlined in my comment[1]. Slowly loosening a valve is a better idea. That being said, in no way, shape or form am I an authority on the subject. https://news.ycombinator.com/item?id=48254381 https://news.ycombinator.com/item?id=48254381
- DannyBee 4mo agoThe standard choice for MMA processing is actually stainless steel, because carbon steel/iron/etc scavenge the inhibitor used to prevent thermal runaway. HDPE would work, and often how it is transported in drums, but for actual processing, everything would normally be spec'd as stainless steel. Which, of course, is pretty spark resistant to begin with. Even if this wasn't true, this is not a hard problem, you can use non-sparking tools, proper coolant, lots of things to avoid sparks. Or you know, we could require that highly flammable materials subject to thermal runaway have "drill here in case of emergency" patch of non-sparking material or something. The cost of ATEX/Class 1 Div 1 compliance would not really go up if you required this.
- VTimofeenko 4mo agoInb4: I don't work in the industry, my knowledge is limited to a faint memory of a college course on fluid dynamics. If I recall correctly, high pressure ignitable stuff can spontaneously turn !!FUN!! in absence of heat if it is suddenly relieved through a pinhole. Basically jet is followed by a ring-like zone where the stuff mixes with oxygen. Jet creates tiny zones of very high temp, thus igniting the mixture ring that follows.
- DannyBee 4mo agoThis is true in other cases but in this case they are actually hoping it leaks
- VTimofeenko 4mo agoMaybe the thought process is that leak would effectively be pressure normalizing over a larger area and more gradually than creating a tiny hole, so whatever I said about jet ignition would not be applicable
- DannyBee 4mo agoSo MMA has a fairly high autoignition temperature - it's >815F (gasoline is like 475F). It also has a fairly small explosive concentration range (2-12%). (the inhibitors it gets mixed with are about the same autoignition temperature, but have higher flashpoints). In any case: 1. The pinhole issue can be resolved pretty easily by making a big hole instead of a small one :) 2. MMA is normally stored at ~0psi. The increasing pressure here is from runaway polymerization boiling the liquid (the runaway comes from the polymerization being strongly exothermic). These tanks are not built to handle very much pressure, usually a few psi max. I doubt whatever the tank pressure is currently qualifies as the kind of high pressure you are talking about. 3. There is apparently a significant crack now that is relieving most of the pressure. Which is preventing it from bursting. Assuming the crack didn't exist before this all occurred (so far the prevailing theory is it did not, but who knows how it will turn out), it almost certainly started as a pinhole that propagated, so if it was going to ignite the way you said, it would have happened already. My guess - even if what you say is 100% correct, the pressure is never high enough to cause issues, even with pinholes.
- peterbecich 4mo agoWhat about airlifting a containment vessel on top of it? To lessen the impact of an explosion?
- keepamovin 4mo agoI refer you to this excellent literature review of the topic: https://www.youtube.com/shorts/M9AXXLAonh8 https://www.youtube.com/shorts/M9AXXLAonh8
- randerson 4mo agoWhat if built a containment dome and then filled it with cold water?
- keepamovin 4mo agowater is incompressible. Blast overpressure is way more damaging in it
- artisin 4mo agoThe escalation from a cute firecracker, that's a bit dangerous, to holy hell, that's not a firework, that's a hand grenade is sublime.
- keepamovin 4mo agoYes, and hard to stop watching. Really want to find out what happens to that steadfast pot.