Massachusetts gas fires: Another technological tragedy
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Massachusetts gas fires: Another technological tragedy
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Re: Massachusetts gas fires: Another technological tragedy
#2"All of these events feel like unnecessary disasters—if we were just a little smarter, we could have avoided them—but the fires in Lawrence are particularly tormenting in this respect. With an aircraft 35,000 feet over the ocean, you can’t simply press Pause when things don’t go right. Likewise a nuclear reactor has no safe-harbor state; even after you shut down the fission chain reaction, the core of the reactor generates enough heat to destroy itself. But Columbia Gas faced no such constraints in Lawrence. "
Pretty interesting comparison. Arguably airplanes can coast down and nuclear reactors (especially Gen-IV low-pressure ones like sodium metal or molten salt) can passively cool their nuclear decay heat post shutdown without external power. But it is true that TMI and Fukushima were not chain reacting, they were both decay heat cooling problems. For those unfamiliar with this, a chain reactor immediately drops to about 7% of full power after shutdown and then exponentially decays to 1% after a day and half a percent after weeks. Turns out 1% of a gigawatt is still a lot.
On the nuclear topic, I'm annoyed that natural gas accidents that cause deaths get way lighter media treatment than nuclear accidents like TMI that cause no deaths.
Re: Massachusetts gas fires: Another technological tragedy
#3The Chemical Safety Board produces some pretty fascinating videos that reconstruct the chains of events that led to large industrial accidents in chemical plants. The videos normally conclude with recommendations for voluntary actions industry can take to prevent similar incidents in future. They basically summarize the results of detailed investigations by CSB agents.
The videos are well produced and, apart from those accidents that involve injury or death, they are quite entertaining if you happen to be in a forensic frame of mind.
Here’s an example of one of their videos: https://youtu.be/_icf-5uoZbc
Re: Massachusetts gas fires: Another technological tragedy
#4"All of these events feel like unnecessary disasters—if we were just a little smarter, we could have avoided them—but the fires in Lawrence are particularly tormenting in this respect. With an aircraft 35,000 feet over the ocean, you can’t simply press Pause when things don’t go right. Likewise a nuclear reactor has no safe-harbor state; even after you shut down the fission chain reaction, the core of the reactor gen…
Turns out 1% of a gigawatt is still a lot.
Just to be pedantic, nuclear plants generate electricity at about 33% efficiency. So to get 1000 MW of electricity, you start with about 3000 MW thermal.
Turns out 1% of three gigawatts is even more. :)
Re: Massachusetts gas fires: Another technological tragedy
#5"All of these events feel like unnecessary disasters—if we were just a little smarter, we could have avoided them—but the fires in Lawrence are particularly tormenting in this respect. With an aircraft 35,000 feet over the ocean, you can’t simply press Pause when things don’t go right. Likewise a nuclear reactor has no safe-harbor state; even after you shut down the fission chain reaction, the core of the reactor gen…
Turns out 1% of a gigawatt is still a lot. Just to be pedantic, nuclear plants generate electricity at about 33% efficiency. So to get 1000 MW of electricity, you start with about 3000 MW thermal. Turns out 1% of three gigawatts is even more. :)
Truth. The ones I'm designing are generally like 38% efficient and 300 MWe scale so pardon my slightly unconventional sizing.
It's definitely a lot. But nothing naturally-circulating sodium metal through 4 redundant NaK-air dump heat exchangers can't handle.
Re: Massachusetts gas fires: Another technological tragedy
#6The Chemical Safety Board produces some pretty fascinating videos that reconstruct the chains of events that led to large industrial accidents in chemical plants. The videos normally conclude with recommendations for voluntary actions industry can take to prevent similar incidents in future. They basically summarize the results of detailed investigations by CSB agents. The videos are well produced and, apart from tho…
These are produced like one of those Air Crash Investigation type shows.
Re: Massachusetts gas fires: Another technological tragedy
#7Earlier quoted context omitted.
Turns out 1% of a gigawatt is still a lot. Just to be pedantic, nuclear plants generate electricity at about 33% efficiency. So to get 1000 MW of electricity, you start with about 3000 MW thermal. Turns out 1% of three gigawatts is even more. :)
Truth. The ones I'm designing are generally like 38% efficient and 300 MWe scale so pardon my slightly unconventional sizing. It's definitely a lot. But nothing naturally-circulating sodium metal through 4 redundant NaK-air dump heat exchangers can't handle.
HN, the place where an article using an analogy of nuclear reactors probably means that an actual nuclear reactor designer will comment on state-of-the-art nuclear reactors.
Re: Massachusetts gas fires: Another technological tragedy
#8Even my air compressors have blow off valves, did something get lost in the advancement of technology from the boiler days ????
it seems to be a pretty stupid design that
doesn't have relief valves.
Re: Massachusetts gas fires: Another technological tragedy
#9I realise this is beside the point of the article, but gas distribution seems like an obsolete and dangerous technology to me.
For cooking, induction, for heating, heat pumps.
Re: Massachusetts gas fires: Another technological tragedy
#10While they were replacing an old system with a new system, they had inadvertently created an interim (hybrid?) system that wasn't as safe as either the old or new:
> The cause of the accident was not a leak or an equipment failure or a design flaw or a worker turning the wrong valve. The pressure didn’t just creep up beyond safe limits while no one was paying attention; the pressure was driven up by the automatic control system meant to keep it in bounds. The pressure regulators were "trying" to do the right thing. Sensor readings told them the pressure was falling, and so the controllers took corrective action to keep the gas flowing to customers. But the feedback loop the regulators relied on was not in fact a loop. They were measuring pressure in one pipe and pumping gas into another.