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@quantian1 correctly determined that this was an ammonium nitrate blast by analyzing the footage: https://twitter.com/quantian1/status/1290695231910875136 http
by sillysaurusx 6y ago
@quantian1 correctly determined that this was an ammonium nitrate blast by analyzing the footage:
https://twitter.com/quantian1/status/1290695231910875136 https://twitter.com/quantian1/status/1290695231910875136
CHEMISTRY FACT: Explosives have characteristic "detonation velocities" at which shockwaves expand. Smartphone video records at 30 FPS, so the adjacent frames here suggest the front expands at ~100 m/(1/30 sec), or 3,000 m/sec. Consistent with ammonium nitrate, not black powder.
This was confirmed a few hours later:
https://twitter.com/BBCBreaking/status/1290758551737192455 https://twitter.com/BBCBreaking/status/1290758551737192455
Lebanese president blames 2,750 tonnes of ammonium nitrate left in warehouse unchecked for six years for devastating Beirut blast
EDIT: By the way, one of my friends was almost killed by the explosion. Thankfully they're ok. But they said:
https://twitter.com/cyrilzakka/status/1290766217989500928 https://twitter.com/cyrilzakka/status/1290766217989500928
This was terrifying to experience. Hospitals are being overrun with injured people. We need blood donations and disaster relief. Help however you can.
As a US citizen, is there any way I can help directly? Is there any organization that ships blood donations directly to a disaster site? I suppose that would be very difficult, so the answer is probably no; it's frustrating not being able to assist.
- chmod775 6y agoSome chemist acquaintances of mine suggested the same from just looking at the footage immediately after. Along with some scary explanations of what fast shockwaves like that do to human blood vessels. I was convinced this stuff should be outlawed for most uses pretty fast. https://en.wikipedia.org/wiki/Ammonium_nitrate_disasters https://en.wikipedia.org/wiki/Ammonium_nitrate_disasters Though on the other hand, the number of incidents and deaths aren't that high considering how prevalent it is. It's just that a critical failure of handling that stuff is quite spectacularly bad.
- 082349872349872 6y agoWhat do you recommend using for fertiliser in its place? (I'm sure someone's thought about this idea before. Timothy McVeigh did his mad bombing with typical rural materiel. Not so fun fact: the VBIED predates the internal combustion engine.)
- BoorishBears 6y agoI think there's some meta commentary here, having someone propose "this dangerous stuff might be getting clamped down on soon". One of the most important materials in the history of modern civilization, that enabled us to get to a place where we can all sit around on HN and not worry how our food is grown
- new2628 6y ago> What do you recommend using for fertiliser in its place? Horse manure :)
- famouslastwords 6y ago> What do you recommend using for fertiliser in its place? > Horse manure :) I surely don't want to be around when 2,750 tons of horse manure detonate :D
- nradov 6y agoAmmonium nitrate is essential as a fertilizer. There are no cost effective alternatives so we'll have to just accept the risk.
- zsellera 6y agoYou can decrease such risks by mixing carbonate minerals (calcium-carbonate and magnesium carboante) into the AN fertilizer, as done in EU counties (and probably in the rest of the world as well).
- raducu 6y agoIsn't it also used as a cost effective explosive in some places? I mean, perhaps thats the reason it was not made inert when it was fabricated in Ukraine. It was on the Lebanese authorities to properly store or dispose of it after they seized the shipping.
- regularfry 6y agoIt's mixed with diesel and used as a quarrying explosive.
- Sharlin 6y agoNot to mention as a historically popular homebrew explosive for less than legal uses.
- menybuvico 6y agoNot to mention that you don't need to store 2750 tonnes of it in a warehouse in a harbour in a large city like Beirut.
- gonzo41 6y agoThe natural heat was the killer. IF twitter was right the fire started from sparks from a welding on a door. The AN must have already been decomposing in the heat and under weight just waiting. I wonder how often this storage facility was at a critical point like this. Like how many hot days. How often before this. It makes you think about all the other risks sitting out there just waiting for a small spark.
- pstrateman 6y agoThere's no real economical alternative fertilizer.
- rtx 6y agoYup, you can see water vapourize.
- nottorp 6y ago> I was convinced this stuff should be outlawed for most uses pretty fast. Let's outlaw cars and kitchen knives as well. Oh and... guns? Outlaw guns in America? :) They can be dangerous too.
- colordrops 6y agoTrump is saying that military intelligence indicates that it's a bomb: https://m.youtube.com/watch?v=tPvH-CqH7Q8 https://m.youtube.com/watch?v=tPvH-CqH7Q8 Edit: why am I being downvoted. I am not agreeing with him or saying he is right. Just stating what was said. It seems noteworthy that the president of the US commented on it regardless of accuracy or trustworthiness.
- erk__ 6y agoUnnamed defence officials are contradicting it say they have no idea what he is talking about. https://edition.cnn.com/2020/08/04/politics/defense-officials-contradict-trump-beirut/index.html https://edition.cnn.com/2020/08/04/politics/defense-official...
- avh02 6y agoWhen I was trying to get as much information as I could (I'm a Lebanese abroad) I automatically mentally filtered out/skipped what trump was saying. Literally not worth the time. Anything officials say unofficially has more value to me.
- moksly 6y agoWhy is Trump used as a source on HN? I don’t think I’ve ever seen that man say something that was useful or true. I’m not American, mind you, so I’m certainly biased because he’s mainly in our media when he does something stupid, but everything I have ever heard him say about Europe has been so far from the truth that it’s hard to take his word on anything.
- p1necone 6y agoI think not being American is a useful precursor to saying useful things about Trump, that way you aren't quite as close to the political tribalism that causes people to think "both sides" should be taken seriously.
- numpad0 6y agoIt might be worth mentioning in some context, just not necessarily in the form it was mentioned above.
- peteretep 6y ago> help directly You could do much worse than donating to the Red Cross and selecting “Disaster Relief”, and if you want to take an action, call your representatives and let them know how important you’d find a robust USAID response. Neither are sexy options, but both will have an effect https://www.redcross.org/donate/D072002.html https://www.redcross.org/donate/D072002.html
- TazeTSchnitzel 6y agoThat's the American Red Cross though, will the money go to Lebanon?
- lucretian 6y agoit will not. more direct resources: https://www.independent.co.uk/life-style/beirut-explosions-lebanon-how-to-help-victims-donate-blood-red-cross-a9654781.html https://www.independent.co.uk/life-style/beirut-explosions-l...
- nerdponx 6y agoDoes MSF have operations in Lebanon?
- est31 6y agoYes, in fact most international aid organizations have major operations in Lebanon, because there is a large population of Syrian refugees, currently about a Million. Per capita, Lebanon takes in the most refugees from the war, at about 1 refugee per 4 ordinary inhabitants. It would be comparable to the US taking in 80 million refugees. Extremely impressive hospitality. They should absolutely be helped now that it's their turn to need it. https://en.wikipedia.org/wiki/Refugees_of_the_Syrian_Civil_War_in_Lebanon https://en.wikipedia.org/wiki/Refugees_of_the_Syrian_Civil_W...
- taneq 6y agoIt's a different branch of the Red Cross, but I gave them some money back when the Philippines was hit by an earthquake and a cyclone in quick succession. I swear they spent more on sending me big glossy fundraising brochures every few months for the next decade than I'd donated in the first place. I later read that the Philippines only got a small percentage of their donations for that campaign. Never again.
- throwaway_pdp09 6y ago(utter newbie here): "Explosives have characteristic "detonation velocities" at which shockwaves expand" but the detonation velocity isn't that; from https://en.wikipedia.org/wiki/Detonation_velocity https://en.wikipedia.org/wiki/Detonation_velocity "Explosive velocity, also known as detonation velocity or velocity of detonation (VoD), is the velocity at which the shock wave front travels through a detonated explosive." I assume that for an infintely sharp explosion, the shock front would rapidly decelerate to something resembling the speed of sound in the medium? - I can't imagine a shock front in the air at 3km/sec (~ 2 miles/sec) not totally utterly destroying everything, be it building or large living organism, literally shredding it. Are you sure that's right?
- codethief 6y agoDo keep in mind that the energy density of the wave necessarily falls off with (at least) 1/r², r being the distance.
- Donthatme 6y agoLooking into blast waves might be of interest. The jargon of the difference between a shock wave and a blast wave somewhat depends on the sub field of interest.
- ashtonkem 6y agoYou could tell it wasn’t a military explosive by the noise. Military explosives tend to be of the high speed type, and tend to make a sharper snap. This looked and sounded more like what you’d see in mining, which is pretty close since ANFO (made with ammonium nitrate) is indeed a mining explosive.
- TooSmugToFail 6y agoBut what about the regular shape of the blast? Looking at the videos of Tianjin disaster, there are multiple large explosions, each with a massive fireball, highly irregular, fiery projectiles flying everywhere etc. The massive blast in Beirut was a singular event, with no preceding or subsequent blasts of similar magnitude. As if the ignition of the material was very efficient.
- beowulfey 6y agoHow many blasts from fire have you seen? How many blasts of AmNH4? If it’s more than 3, you may be able to form a trend of what to expect. But wait—-are you controlling all variables? Is every characteristic identical? Were they all open warehouses? The same amount of fuel? The same air humidity level? My point is, there’s no way to know what a characteristic explosion should look like, unless you are an explosives expert with hundreds of prior experiences. Also, I’d recommend taking the time to learn Bayes theorem. It’s currently also on the front page.
- ashtonkem 6y agoWhat you’re describing is the difference between a detonation and deflagration. Explosions are usually extremely regular in shape unless if obstructed in some way due to the way shock waves propagate in open air. And the Beirut explosion wasn’t just one detonation. There were two explosions, with a large fire and small detonations prior to the largest detonation. In all of the videos you can see a huge plume of smoke before the final detonation, as well as fire and smaller explosions if the video was close enough.
- madaxe_again 6y agoThere’s an even easier giveaway - the bloody great cloud of NO2 that immediately appears. I think anyone who’s ever seen a fertiliser dump go up will have immediately recognised this explosion - reminded me of my childhood, when we’d regularly go and explode things with the stuff.
- zimpenfish 6y agoDr Moudhy Al-Rashid has a thread of ways you can help. https://twitter.com/Moudhy/status/1290969922672173057 https://twitter.com/Moudhy/status/1290969922672173057