Comments by "David Elliott" (@davidelliott5843) on "Plainly Difficult" channel.

  1. The engineer should have called out the problem and be prepared to walk away when he’s ignored. That way he has delivered his professional responsibility. This engineer kept quiet, sealing his own fate and the townspeople below.
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  2. This event proved that NASA management had learned next to nothing from the 1967 Apollo 1 oxygen fire. The whole setup was fundamentally flawed, yet they went ahead anyway. The Shuttle program was fundamentally flawed yet they went ahead anyway. Shuttle was an engineered botch job from day one. The surprise is there were only two catastrophic accidents.
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  3. My father in law a dairy farmer always said “Mad Cow” was caused by organophosphate insecticide. He was required by law to treat his cows for potential warble fly infestation. The chemical was applied at a high concentration along the animal’s spine. The farmer wearing full body safety gear and respirator. After doing the job many cows had BSE “the staggers” but they seemed to recover. My F-I-L despite his carefully used equipment was sick for days afterwards. He flatly refused to ever do it again saying he would go to prison if necessary. He always believed CJD was caused by OP pesticides.
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  4.  @ligmasack9038  The nuke covers-ups will be the least that Soviets did. There will be numerous chemical and toxic cover-ups causing misery to many more people.
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  5. UK had power station cooling towers collapse in high winds. Ferry bridge I believe. Thankfully they were fully built and nobody was hurt.
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  6. Requiring the bridge to undergo less than 1 degree of misalignment during construction was a clear sign of poor design. 1 degree on a structure of that length is tiny and almost certainly impossible to achieve. Add in the poor design that concentrated tension loads at the ends and the result was inevitable.
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  7. If there had been an “exchange” while they were submerged the submarine crew needed to know if it was safe to go outside. Therefore all nuke subs had rad detectors on the outside.
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  8.  @dt99022  A bridge that falls like a pack of cards after a single impact suggests it was fundamentally flawed. Hopefully the replacement will be a cable stay type with support piers away from the water.
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  9. Toxicity of fly ash depends how well the boilers burn the coal. Older boilers had higher“carbon in grits” so more unburnt nasties. However ash slurry is incredibly searching and quickly sets like concrete. Run off from coal mine drainage is many times worse and often a serious issue from disused mines.
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  10. “Easy to build and cheap” is good when you’ve designed out the intrinsic hazards. It’s the worst of all worlds when you have an intrinsically dangerous design. It’s even worse when the control rods take minutes to insert and the reactor can runaway in less than a second.
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  11. The nuclear industry used solid oxide fuels because that’s the best way to create bomb grade isotopes. Despite the serious safety issues the industry stuck with it because that’s where the development money had gone. Weinberg’s molten salt reactors solved the problem by using a liquid fuel (salt heated until molten). He was shut down by Nixon in early 1970s. The molten can’t overheat because thermal effects inside the core slow down the nuclear reaction. For many reasons, the molten salt reactor is intrinsically safe and therefore very low cost. The big question is why are we not using them everywhere?
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  12. The (lack of) thinking behind this points to the reasons why Fukushima happened. “what if?” scenarios seem to have been ignored. Fukushima was vulnerable because they placed all of the transformers and emergency generators where they could all be washed over by a tidal wave. Nobody noticed the glaring error the rest is ...
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  13. The towers were built by hard left politicians. They wanted the people corralled and controlled regardless of the social consequences. Even worse, it would have been cheaper to renovate and restore the old terraced houses.
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  14. Call fires are incredibly hard to extinguish. Coal stocks ate power plants steel mills etc have to be carefully managed. Pouring on water often makes it worse as the violent conditions ate the seat of the fire crank the water and the hydrogen/oxygen fed the fire. There is evidence that Titanic was steaming so fast though the ice fields because her stokers were digging out a bunker fire. Heat had already buckled the bulkheads which no doubt cause the ship to sink faster than expected. I worked on a coal fire powered plant where we had a nasty bunker fire. The coal was run though the mills, but ash and heat from the fire cause it to hang up in the bunker. Shifting it with long steel poles from above needed breathing apparatus and fire protection teams on hand as letting in air could lead to a sudden flare-up.
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  15. The engineers said the chances of failure were x%. They should have said the chances of survival are y%. The difference in emphasis could well have swung the management to take real action rather than just trust to luck.
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  16. They fixed the tyre puncture by filling the tyre with concrete.. But only just under the hole. The rest of the tyre is perfectly normal and the wheel rolls along just fine. Honest.
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  17. This sounds like a similar situation to the failure of Genoa Morandi Bridge in 2018. In Italy the root cause was corrosion of steel tension cables. However (like Florida), a single point failure led to total collapse.
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  18. This was a solids tower (fell over with almost no damage, built on inadequate foundations. Look how the piles pulled out but still broke off.
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  19. I would like you to take all of the safety issues covered with the PWR/BWR and run them against the Moltex Static Salt Reactor. The company say their reactor has none of the failure points associated with solid fuels and high pressure cooling. That makes them intrinsically safe and therefore cheap to build and operate.
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  20. Don’t forget Flixborough and Fauld/Hanbury.
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  21. Moltex and Elysium have already proved that fast spectrum molten salt reactors will work perfectly well. No fancy metal coolant no steam inside the nuclear island and no pressure inside the reactor. Even better, the high negative temperature coefficient means it naturally follows the load with no operator input. What’s not to like?
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  22. How stupid do you have to be to think any of this is a good idea. Risk = 99.9% Benefit = 0.1%
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  23. Alvin Weinburg (who held the main patents for PWR reactors) always said they are fine for small power plants immersed in water as used in submarines and ships. However he said scaling up to utility scales is too risky after should not be done. This pioneer of nuclear power was immediately told to shut up or leave the industry. Three Mile Island happened about 5 years later. Weinburg ran the MSRE (molten salt reactor experimental) for five years during 1960s/70s. The MSR ran at atmospheric pressure - no need for high pressure pumped water and steam. It was also passively self- regulating. Weinburg disconnected the cooling loop while keeping the controls at full power. Completely passively, the reactor stayed well within temperature limits. Doing this with any PWR/BWR would cause a Fukushima type. accident.
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  24.  @P7777-u7r  That depends on how you fuel and cool your reactor. The molten salt reactor invented by Alvin Weinburg (in 1960s) is intrinsically safe. There is no internal pressure. Containment is thick concrete. Xenon escapes from the core so cannot poison the reaction. Elements like Iodine 131 and caesium 137 form salts in the fuel. Cannot potentially escape as gasses. The temperature coefficient is highly negative. It cannot overheat because reactivity quickly slows. There is no water or steam inside the core removing the numerous hazards. Hydrogen cannot be generated and voids in the core are not possible. Molten chlorides are less corrosive that highly pressurised hot water. The British Moltex puts the fuel into fuel pins - vented to release fission gasses like xenon. It’s also a fast spectrum so will burn the 95% unused energy remaining in used oxide fuel pins.
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  25. Sugar works well in amateur rocket motors.
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  26. In UK, the gas mains have been replaced with ultrasonic welded PEx. However water mains are still leaking 20% of our water.
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