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Posted: Thu Mar 25, 2010 2:50 am
by JohnP
Look, forget the megawatts. If it was megawatts they'd be exceeding other "LENR" experiments by a factor of a million. The thing was done in a calorimeter, which means the result was a temperature blip in a small qty of water. It coulda been from a grad student smoking a joint too close to the apparatus.

Posted: Thu Mar 25, 2010 4:56 am
by MSimon
JohnP wrote:Look, forget the megawatts. If it was megawatts they'd be exceeding other "LENR" experiments by a factor of a million. The thing was done in a calorimeter, which means the result was a temperature blip in a small qty of water. It coulda been from a grad student smoking a joint too close to the apparatus.
Very funny.

Posted: Thu Mar 25, 2010 8:38 am
by Giorgio
JohnP wrote:Look, forget the megawatts. If it was megawatts they'd be exceeding other "LENR" experiments by a factor of a million. The thing was done in a calorimeter, which means the result was a temperature blip in a small qty of water. It coulda been from a grad student smoking a joint too close to the apparatus.
On a second tought, depending on the number of the students present in the lab and the size of the joint it might have been Megawatt after all...... :D

Posted: Thu Mar 25, 2010 2:10 pm
by MSimon
Giorgio wrote:
JohnP wrote:Look, forget the megawatts. If it was megawatts they'd be exceeding other "LENR" experiments by a factor of a million. The thing was done in a calorimeter, which means the result was a temperature blip in a small qty of water. It coulda been from a grad student smoking a joint too close to the apparatus.
On a second tought, depending on the number of the students present in the lab and the size of the joint it might have been Megawatt after all...... :D
Well it sure seemed that way after breathing the air.

Posted: Thu Mar 25, 2010 2:57 pm
by Tom Ligon
If I understand the operation of that particular calorimeter, the goal is to NOT significantly heat the water in the fish tank. That is supposed to be a heat sink that pretty much stays constant. It provides a uniform guard temperature around the entire cell. The actual measurement of heat flow is entirely within the cell.

There is a plethora of information of various schemes for calorimetry on the web, and one key to look for is the use of a guard ring or guard shell. These are critical in all precision measurements. The idea is to avoid heat leaks in or out of the apparatus by actively controlling one component so that it stays at the temperature of the surrounding medium. Typically you have an insulator around an actively-controlled shell, and make the temperature difference across the insulation zero, so there is no heat gain or loss via that mechanism. Then, all the heat you remove from that insulated shell is due to the heat source it contains.

This method, with variations, is used in calorimetry, thermal insulation testing, and measurement of thermal conductivity of good thermal conductors. I have performed the latter two. It is closely related to the use of a guard potential in electrometers and megohm meters.

They are looking for watts or less with that apparatus.

The device probably also contains a resistive heater with which to calibrate it.

Posted: Thu Mar 25, 2010 3:11 pm
by MSimon
Calibrating such a setup is very difficult for small amounts of heat. Too much feedback and you are feeding heat into the device. Too little and you are extracting heat.

IMO a tank of water unstirred has to be one of the worst set-ups I could imagine. You get lags. better is a heat pipe that can be heated (in the case of exothermic reactions) because the delta T across them is low and the delay is low. And then there is the problem of matching (or calibrating) the temperature sensors.

Lags screw up feedback if they are not well matched to the lags in the heat producer. And then there is the thermal lag of the sensors.

Guards work in electronics because of the speed of light vs. the rate of change of signal.

How would I rate the water tank if it functions the way Tom explained? Amateur hour.

Posted: Thu Mar 25, 2010 11:52 pm
by Axil
For chemists, LENR opens up a new universe of possibilities.

One of the important applications of LENR is the transmutation of fission waste into stable isotopic forms in very short time frames. Current experience in LENR research shows that when LENR transmutation occurs, the invariable result is a stable isotope.

As a prime application, the remediation of nuclear waste from fission can occur in a matter of months notwithstanding any energy production gains from the LENR process. This LENR nuclear waste stabilization technology would remove the stigma from fission which paints it as a dirty and dangerous technology.

Such LENR nuclear waste purification applications can also treat coal ash to economically remove its radioactive waste byproducts.

Posted: Fri Mar 26, 2010 7:09 pm
by StevePoling
Axil wrote:Such LENR nuclear waste purification applications can also treat coal ash to economically remove its radioactive waste byproducts.
A couple summers ago I went to visit the plant where my daughter was interning. I pointed out to one of her fellow-interns that coal plants emit more radiation than nuke plants. He said, "Yeah!" Then made a funny look, "Hey, how'd you know that?" He expected everyone who's not a nuclear engineering student to get their information about nukes from "The China Syndrome."

I think that we'll see a lot of rad-waste burning fast-neutron designs for fission plants in the next few years. My daughter's senior thesis at Michigan was one such. It'll add insult to injury if nukes end cleaning up coal plants' fly-ash.

Posted: Fri Mar 26, 2010 8:03 pm
by Axil
The Chinese are now mining coal ash piles for uranium. These piles assay out higher in uranium content than some uranium mines do. This is on top of the removal of half of those rad materials that were vaporized in the compulsion of coal and have already gone up the stack as smoke.

Burning coal is some bad stuff.

Posted: Sat Mar 27, 2010 11:21 am
by Art Carlson
Axil wrote:The Chinese are now mining coal ash piles for uranium. These piles assay out higher in uranium content than some uranium mines do.
That's incredible. Do you have a reference for it?

Posted: Sat Mar 27, 2010 2:07 pm
by Tom Ligon
It probably varies by region. Here in Manassas Virginia we have streaks of alluvial deposits that have an annoyingly high level of uranium and the associated other radioactive elements. They were deposited in sediments from the erosion mountains that used to be larger than the Himalayas. There is a region in China from the same group of mountains ... plate tectonics is another field that was pretty hard to believe at one time.

If you live over such a deposit, you have radon trouble. If not, you don't. The streaks follow old stream beds and are very sharply defined.

I can see peat bogs and swamps might build up quite a load, but it would be regional.

Posted: Sat Mar 27, 2010 2:17 pm
by BenTC
Art Carlson wrote:
Axil wrote:The Chinese are now mining coal ash piles for uranium. These piles assay out higher in uranium content than some uranium mines do.
That's incredible. Do you have a reference for it?
from google...
http://www.nucoalenergy.ca/news/237/
http://www.world-nuclear-news.org/newsa ... x?id=14224
http://atomicinsights.blogspot.com/2007 ... nergy.html
http://www.spartonres.ca/pressreleases/ ... -2010.html

Posted: Sat Mar 27, 2010 4:41 pm
by Art Carlson
BenTC wrote:
Art Carlson wrote:That's incredible. Do you have a reference for it?
from google...
Incredible but true. Thanks for the refs.

I remember reading that, at least according to some calculations, the largest source of radiation to the public from nuclear power was radon leaking from uranium mine tailings. Is that still considered to be true? Is radon from coal ash then also a significant problem? How would it compare to mine tailings for the same energy production?

Posted: Sat Mar 27, 2010 4:52 pm
by StevePoling
Art Carlson wrote:Is radon from coal ash then also a significant problem? How would it compare to mine tailings for the same energy production?
Not radon, uranium. My understanding is that trace amounts of uranium are distributed in coal deposits. The process of burning releases the uranium from the coal. The uranium ends up concentrated in the fly ash.

I don't know how these concentrations compare with other waste sources.

Posted: Sat Mar 27, 2010 6:27 pm
by BenTC