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NYC Wind Turbine Failure 9

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What do they do with the composite structures from old aircraft, or are there not enough of them in circulation to be an issue yet?


EDMS Australia
 
There is loads in circulation but there isn't a huge volume of hull strips occurring yet.

 
FreddyNurk said:
What do they do with the composite structures from old aircraft, or are there not enough of them in circulation to be an issue yet?

Nothing.
You can be sure plenty of research is being done to "greenwash" this. There are some processes, but they're all expensive. It's the typical result like many other recycling processes - the cost is too high, especially in consideration of the lower quality than the original material.

To the ones who make the big breakthrough, there's a chance the big auto and aero OEM's would like to talk to you.


 
All things made of glass-reinforced plastic or other composites have the same issue with respect to recycling - be it windmill blades or aircraft hulls or Chevrolet Corvette (or BMW i3) bodyshells or certain packaging materials or the translucent cover over your patio.
 
One of the problems with nuclear waste is that it contains a large percentage of transmuted isotopes of Plutonium, which is not only one of the most poisonous substances known, it's also the material that most nuclear weapons use for their fissionable mass, and even if you don't use it to create an actual atomic bomb, it would be the ideal material to lace a conventional bomb with to it make a very 'dirty bomb'. And while it is true that you can convert the waste from one nuclear power plant into fuel for another, the design of the second plant won't be exactly the same as the first, so the fuel can't actually be recycled. Eventually the cycle reaches a point where it's no longer practical, at least not based our current understanding of how to design nuclear power plants.

Now if you really want to invest in a new power source that would address all of the issues currently being obsessed over, then we should be putting our R&D dollars into the development of FUSION reactors. While the science is understood, it's the physics that we're still having to wrestle with.

Anyway, those are my thoughts, for whatever they're worth.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
FUSION -that one!! That's what we should be putting ALL our efforts in to. Thanks John.

Bill
 
How much carbon is released by refineries and upgraders to create the heat to drive the processes?
For every ton of carbon going into an upgrader in tar, how many pounds of carbon is released before gasoline comes out of the refinery?

How does the carbon footprint of gasoline by itself compare with carbon foot print of gasoline from the ground to the tank?
If the energy needs of upgraders and refineries were met by alternate sources, wind, water, solar or nuclear, how much would the carbon emissions of the transport industry be reduced?
How much could North America's carbon emissions be further reduced by switching from "Clean" diesel to "Clean" gasoline", to "clean" propane?
As for nuclear waste fears, JAE's link is a good read.


It has been reported that the transportation industry accounts for 23% to 25% of the carbon emissions.
Consider: Using alternate energy to upgrade to "clean" synthetic propane, we will have drastically reduced our carbon emissions and to a great.
A argument could be made that we may make nuclear power portable with very little carbon emission.


Bill
--------------------
"Why not the best?"
Jimmy Carter
 
My feelings about nuclear energy are summarized well by this:

XKCD_log_scale_cljbb1.png


The dreamer in me believes that a universal world commitment to safe nuclear energy would ensure a stable reliable energy supply for the entire human race for a very long time. Energy abundance would help the standard of living of most people on the planet to such a high level that very few of them would feel the need to harm anyone else.
The problem is getting to this state of energy nirvana.
Unfortunately, we live on THIS world, where half the people do not have a stable, accountable government to allow this NOT to be perverted into weapons, nor universal education to allow citizens to make use of such an abundant energy supply.

John,
There's no physical problem with nuclear waste. It's easily stored and safely handled all the time. It's only a problem because people insist on not using it for energy. Consider: it heats itself from its own radioactivity, meaning it is also an energy source. Meaning: a different reactor type could use it to produce more electricity. The problem with nuclear "waste" is entirely political. Making that "waste" into another reactor fuel to use for 2nd generation energy production exposes the material to the exterior world. As you noted, in between it's more useful for weapons, so the risk comes from the potential abuse.


 
SparWeb said:
The dreamer in me believes that a universal world commitment to safe nuclear energy would ensure a stable reliable energy supply for the entire human race for a very long time. Energy abundance would help the standard of living of most people on the planet to such a high level that very few of them would feel the need to harm anyone else.
At a certain point we needed to realize that we can't consume our way out of this problem but that point has long since come and gone. We have a perverted view of what constitutes a high standard of living I think.

Conservation should be the first part of this equation, not the last. As someone else said, "there is no such thing as a free lunch." This is especially true when your tablemates are gluttons.

Even if we were to reach this state of energy nirvana, we would still consume ourselves into oblivion. It is our species' fatal flaw. And will be the cause of our, and many other organisms, extinction.

It's not just the carbon cycle that we've broken. We've short circuited every natural cycle (hydrologic, nitrogen, etc.) that we've injected ourselves into in order to facilitate our unfettered growth beyond the planet's carrying capacity for our "standard of living." We also broken all of the natural geographic barriers while we've simultaneously created untold artificial ones; both of which are accelerating life as we know its demise.

"Mad Max"-esque end of days are coming, folks. That's not to say we should give up I guess. Certainly not. Anything that will buy us another, say... 50 years(?) will be appreciated.

I'm personally banking on beneficent aliens who, in addition to bringing us free energy, otherwise correct us of the error of our ways. Beneficence being a coin toss though... I, for one, will welcome our future insect (or alien, or artificially intelligent) overlords.

That's enough doomsaying for the day =) Time to go for a walk in the sun!

 
Very true, my friend.
The climate change scenario is really scary and we need to act and act very fast!
What are we going to tell our grand children and with what face can we face them!!
 
Two comments about the nuclear waste debacle-
1- Control of nuclear waste is possible using current technology and engineering controls, but at a time scale not imaginable to most. The waste stockpiles demand diligence in monitoring and maintenance for tens of thousands of years or more.
2- As with many other imperatives, I think the public by and large is poorly informed about the benefits and perils of nuclear power in general, and waste in particular; the result of being educated by 24 hour news networks and the rants of politicians.

Brad Waybright

It's all okay as long as it's okay.
 
Thanks Brad.
It's fine to point out that the general public is misinformed, but that's universally true about so many subjects, and doesn't encourage anyone to learn more. I prefer to ask questions.

Ask yourself if you can agree with this sentence: There is no such thing as nuclear waste.

There two kinds of radioactive materials: those that we don't use for energy, and those we do. The U235/U238 combo that's put in most reactors is just the stuff with the "goldilocks" level. The ones we don't use for energy are either not radioactive enough, or too radioactive. At the low end are things like Carbon isotope 14, which I'm happy to store in my bones for the future archaeologists to analyze. At the other end is Polonium-210 which I'd prefer not to have on Earth at all. Between these extremes, however, are an abundant variety of materials of different chemistry, life, emission, and daughter products. The utility of most of these materials has not been completely explored.

Calling these products "waste" just calls attention to the EVERYONE's ignorance, including the scientists.

 
Anyone know anything about traveling wave reactors (TWR) Traveling Wave Reactor Wiki. I remember seeing a TED talk about them a few years ago and the concept sounded pretty cool.

The basic concept is to use a small amount of enriched material to basically "light the wick" and it then can burn down previously "spent" nuclear waste like a candle over a period of decades in a sealed reactor. I think the major problems are that TWRs produce too much heat? I think there are problems with cooling medium for the reactor core or something like that.

Andrew H.
 
If I recall correctly, the real issue with the TWR systems is that it's exactly like a candle, once lit, it burns until the fuel has been expended. In other words, it can't be throttled, it's all or nothing. Any unused heat had to be dissipated away immediately and thus wasted.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
SparWeb-
Great discussion! I'd classify 'waste' as anything that is disposed of permanently after it is deemed to be no longer economically useful. That may be different than Webster's but I doubt his would really work in this context anyway.
Take that old T-shirt. Do you give it to Goodwill where it might be re-purposed, or do you throw it in the trash where it heads to the landfill as waste? In the US, the nuclear industry decided long ago that it is cheaper to dispose of used nuclear fuel than to try to recycle or reprocess it. France, I believe, reprocesses most of their used fuel but I think there is still a considerable 'waste' stream that contains elements like strontium and cesium as well as other irradiated material. These elements are dangerous and I don't know what commercial or scientific value they hold. On the weapons side, there are a large number of superfund sites like Fernald and Mound here in Ohio, where you can attribute large areas contaminated with 'waste' to decades of carelessness and apathy. Once you sprinkle the ground with trace radioactive elements, then you turn a small amount of usable material into large quantities of economically un-useful stuff that has to be dug up and moved somewhere. When nuclear plants are dismantled, sizable volumes of neutron-activated materials like stainless steel and concrete must be moved away likewise.
So, using MY definition of waste, then I'd say there will always be significant volumes of material, no longer useful, that heads to the nuclear landfill.

Brad Waybright

It's all okay as long as it's okay.
 
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