5 ms·

Why wouldn't there be passive protection systems designed in? After a big earthquake you don't want to have to also deal with other emergencies (à la Fukushima

by robocat 5mo ago

Why wouldn't there be passive protection systems designed in? After a big earthquake you don't want to have to also deal with other emergencies (à la Fukushima). Aside: One good side-effect of the 2011 Tōhoku earthquake being so horrific is that it stopped the self-obsessed whinging in my city (Christchurch was still trying to recover from an earthquake).

largbae 5mo ago
Based on the article, the inhibitor chemicals _are_ the passive protection system, they just can't be perfect because too much of that stuff ruins the purpose for having the chemical in the first place.
- itishappy 5mo ago
  It can actually make it more dangerous in some ways. When you go to use it, too much inhibitor and the conditions needed to start the reaction will start to get wild, so the reaction will occur faster once started. > The use of high levels of inhibitor can cause the monomer system temperature to far exceed the onset temperature of thermal polymerization under external heating. Once the inhibitor is exhausted, the thermal runaway reaction proceeds at an elevated temperature with a substantial reaction rate and very little reactant/monomer consumption. Source: This fascinating paper linked to by fuzzfactor in yesterday's (edit: 3 days ago, lol) thread: https://iomosaic.com/docs/default-source/papers/polymerization-reactions-inhibitor-modeling---styrene-and-butyl-acrylate-incidents-case-studies.pdf?sfvrsn=993dc4d4_25 https://iomosaic.com/docs/default-source/papers/polymerizati... The comment: https://news.ycombinator.com/item?id=48252245 https://news.ycombinator.com/item?id=48252245
dan_sbl 5mo ago
I believe they tried to inject some chemicals to slow the reaction, but the pump and/or valves failed and clogged.
- robocat 5mo ago
  That is active. Something passive could be submerging the tank in a pool of water (also good for proving spill containment won't leak).
  - colechristensen 5mo ago
    Uh, you can't just disconnect a pressurized 35,000 gallon tank and drop it into a an enormous pool you just keep full under it at all times.
    - robocat 5mo ago
      Riiight. That is exactly what I was thinking.
      - colechristensen 5mo ago
        It's really unclear what you were thinking
    - bagels 5mo ago
      I think the passive version is the tank stays in a pool all the time.
  - cyberax 5mo ago
    Typically you don't have enough surface area for that. The walls are thick enough that thermal conductivity into an ambient-temperature liquid alone is not going to be sufficient.
- kenhwang 5mo ago
  I was thinking maybe have those chemicals sitting in a glass or temperature sensitive container inside the tank. So when there's too much pressure or heat, the container containing the neutralizing chemical is broken like a fuse and the chemical is automatically released.
  - deleted 5mo ago
KennyBlanken 5mo ago
> Why wouldn't there be passive protection systems designed in? Because the US chemical industry has been effectively unregulated for a century and can do whatever it pleases. There's a neutralizing chemical that could have been injected to stop the exothermic reaction in its tracks. They didn't have it on site. A "response team" (likely a contractor that responds to chemical emergencies) did, but by the time they showed up, supposedly things were too damaged to inject it. That neutralizer should have been a Big Red Switch away. They also should have had a deluge system, for example, to cool the tank. With a standpipe for firefighters if there's no water available onsite. Was there? Nope! No requirement for it. Despite the dangers of this stuff being very well documented, it having caused disasters before, etc. Consider that the chemical industry can invent a new chemical and the onus is on everyone else to prove it is hazardous. So what does the US chemical industry do? Spend lots of time "innovating" new versions of chemicals to constantly leverage the 'innocent until proven guilty' scam. Chemical A is found to be cancerous, so they rework it slightly, enough to call it a new chemical even though it's nearly the exact same thing, but we're right back to square one on it "not being hazardous." Protection systems cost money. If something really bad happens the cost of the disaster far outweighs whatever assets the company has hanging around, and in the US, we basically never hold anybody responsible for what they do in the course of their job running a corporation. GM willfully ignored problems with Chevy Cruze ignition switches that caused countless people to die because they'd randomly shut off _and shutting off meant the airbags would get disabled_. Did anyone in those teams, or their managers, ever get held accountable? Nope, not except in some civil suits, where Chevy repeatedly claimed they didn't have any documentation. Well, at some point Congress went after them for something, and in the massive pile of documents lo and behold there wer piles and piles and piles of documentation about the ignition switch issues. A company like that isn't even required to carry a lick of insurance, far as I'm aware. Meanwhile, and I wish I were joking on this - if I want to get a permit to set aside space in front of my apartment building to park a moving truck, I have to carry a million dollars insurance that protects the city. If I park my car blocking an ambulance I get charged with at least one crime, possibly even manslaughter or homicide. Ditto for blocking a fire truck trying to get to a fire. A railroad can do it to half a county, dozens of times a year, and everyone just shrugs as people are harmed or killed, or half a neighborhood burned down. All because private equity is milking the railroad so tight that it's making trains that are miles long instead of lengths that are appropriate for the tracks they're on and won't block fire trucks, ambulances, police cars, school busses, and the general population as a whole. The free license corporate America gets to shit all over society has got to stop.
cratermoon 5mo ago
Why? For the same reason our reactors do not have containment buildings around them, like those in the West. For the same reason we don't use properly enriched fuel in our cores. For the same reason we are the only nation that builds water-cooled, graphite-moderated reactors with a positive void coefficient. It's cheaper.

by robocat 5mo ago

largbae 5mo ago

Based on the article, the inhibitor chemicals _are_ the passive protection system, they just can't be perfect because too much of that stuff ruins the purpose for having the chemical in the first place.

itishappy 5mo ago
It can actually make it more dangerous in some ways. When you go to use it, too much inhibitor and the conditions needed to start the reaction will start to get wild, so the reaction will occur faster once started. > The use of high levels of inhibitor can cause the monomer system temperature to far exceed the onset temperature of thermal polymerization under external heating. Once the inhibitor is exhausted, the thermal runaway reaction proceeds at an elevated temperature with a substantial reaction rate and very little reactant/monomer consumption. Source: This fascinating paper linked to by fuzzfactor in yesterday's (edit: 3 days ago, lol) thread: https://iomosaic.com/docs/default-source/papers/polymerization-reactions-inhibitor-modeling---styrene-and-butyl-acrylate-incidents-case-studies.pdf?sfvrsn=993dc4d4_25 https://iomosaic.com/docs/default-source/papers/polymerizati... The comment: https://news.ycombinator.com/item?id=48252245 https://news.ycombinator.com/item?id=48252245

dan_sbl 5mo ago

I believe they tried to inject some chemicals to slow the reaction, but the pump and/or valves failed and clogged.

robocat 5mo ago
That is active. Something passive could be submerging the tank in a pool of water (also good for proving spill containment won't leak).
- colechristensen 5mo ago
  Uh, you can't just disconnect a pressurized 35,000 gallon tank and drop it into a an enormous pool you just keep full under it at all times.
  - robocat 5mo ago
    Riiight. That is exactly what I was thinking.
    - colechristensen 5mo ago
      It's really unclear what you were thinking
  - bagels 5mo ago
    I think the passive version is the tank stays in a pool all the time.
- cyberax 5mo ago
  Typically you don't have enough surface area for that. The walls are thick enough that thermal conductivity into an ambient-temperature liquid alone is not going to be sufficient.
kenhwang 5mo ago
I was thinking maybe have those chemicals sitting in a glass or temperature sensitive container inside the tank. So when there's too much pressure or heat, the container containing the neutralizing chemical is broken like a fuse and the chemical is automatically released.
- deleted 5mo ago

KennyBlanken 5mo ago

> Why wouldn't there be passive protection systems designed in? Because the US chemical industry has been effectively unregulated for a century and can do whatever it pleases. There's a neutralizing chemical that could have been injected to stop the exothermic reaction in its tracks. They didn't have it on site. A "response team" (likely a contractor that responds to chemical emergencies) did, but by the time they showed up, supposedly things were too damaged to inject it. That neutralizer should have been a Big Red Switch away. They also should have had a deluge system, for example, to cool the tank. With a standpipe for firefighters if there's no water available onsite. Was there? Nope! No requirement for it. Despite the dangers of this stuff being very well documented, it having caused disasters before, etc. Consider that the chemical industry can invent a new chemical and the onus is on everyone else to prove it is hazardous. So what does the US chemical industry do? Spend lots of time "innovating" new versions of chemicals to constantly leverage the 'innocent until proven guilty' scam. Chemical A is found to be cancerous, so they rework it slightly, enough to call it a new chemical even though it's nearly the exact same thing, but we're right back to square one on it "not being hazardous." Protection systems cost money. If something really bad happens the cost of the disaster far outweighs whatever assets the company has hanging around, and in the US, we basically never hold anybody responsible for what they do in the course of their job running a corporation. GM willfully ignored problems with Chevy Cruze ignition switches that caused countless people to die because they'd randomly shut off _and shutting off meant the airbags would get disabled_. Did anyone in those teams, or their managers, ever get held accountable? Nope, not except in some civil suits, where Chevy repeatedly claimed they didn't have any documentation. Well, at some point Congress went after them for something, and in the massive pile of documents lo and behold there wer piles and piles and piles of documentation about the ignition switch issues. A company like that isn't even required to carry a lick of insurance, far as I'm aware. Meanwhile, and I wish I were joking on this - if I want to get a permit to set aside space in front of my apartment building to park a moving truck, I have to carry a million dollars insurance that protects the city. If I park my car blocking an ambulance I get charged with at least one crime, possibly even manslaughter or homicide. Ditto for blocking a fire truck trying to get to a fire. A railroad can do it to half a county, dozens of times a year, and everyone just shrugs as people are harmed or killed, or half a neighborhood burned down. All because private equity is milking the railroad so tight that it's making trains that are miles long instead of lengths that are appropriate for the tracks they're on and won't block fire trucks, ambulances, police cars, school busses, and the general population as a whole. The free license corporate America gets to shit all over society has got to stop.

cratermoon 5mo ago

Why? For the same reason our reactors do not have containment buildings around them, like those in the West. For the same reason we don't use properly enriched fuel in our cores. For the same reason we are the only nation that builds water-cooled, graphite-moderated reactors with a positive void coefficient. It's cheaper.