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Comment: Re:= paracetamol (Score 1) 187

by Muad'Dave (#49469435) Attached to: Acetaminophen Reduces Both Pain and Pleasure, Study Finds

We have at least one instance of that in the US - Excedrin. Their "Extra Strength" formulation has the exact same amounts of the active ingredients as their "Excedrin Migraine" and "Excedrin Menstrual Complete". At least at Walgreens Online they charge $17.99 for 200 Extra Strength caplets and $18.49 for 200 Migraine caplets. In the actual brick-and-mortar stores the prices are usually identical. Walmart's prices are the same.

Comment: Not Esperanto (Score 1) 8

I'm sure you're aware of Esperanto, which is a 'constructed' language proposed as a universal second language. There are also Interlingua, Ido, and Novial, but I don't know anything about them.

The things in Esperanto that turned me off are listed here:

"the use of "Classic Greek and Old Latin singular and plural endings -o, -oj, -a, -aj" - those are unpronounceable to native English speakers ('oj' would be naively pronounced as 'ohgz' or 'oddgz' instead of 'oy').

"letters with circumflex diacritics, which some find odd or cumbersome, along with their being invented specifically for Esperanto rather than borrowed from existing languages; as well as being arguably unnecessary, as for example with the use of instead of w."

An optimal language, IMHO, would have no diacriticals, no gender aside from pronouns (he, she, etc), very few verb tenses (I can indicate time by using more words - "I eat the apple before" vs "I ate the apple" - no verb tense needed), and no ambiguous spelling or pronunciation. With all these limitations, it may sound like caveman language :-)

Comment: Re:So Germany is not a state? (Score 1) 265

Did you stop to think that the article I quoted means "The coal that is burnt in Germany" not "coal that is mined in Germany"? You're too quick to dismiss the source data. Why would an article quote radiation figures for coal that's not being used, as you state? You've repeated this over and over, but I hoped you'd figure out your misunderstanding yourself and that I wouldn't have to point it out to you.

As for the "You started with an insane amount of "radiation" spread by coal plants. Now -- after 3 or 4 posts -- you accept that perhaps maximum 1%" --- I have done no such thing. I used the MOST CONSERVATIVE numbers to prove my point. Even using the lowest figure of 1% you still have to reconcile these facts:

"In the USA, 850 million tonnes of coal was used in 2009 for electricity production. With an average content of 1.3 ppm uranium and 3.2 ppm thorium, US coal-fired electricity generation in that year gave rise to 1100 tonnes of uranium and 2700 tonnes of thorium in coal ash."

If 1% is lost to the atmosphere, simple math (so simple you might be bothered to verify it) shows 11 tonnes of U and 27 tonnes of Th are released. My previous post was indeed in error. I was off by a factor of ten, but not the way you claim - I previously said "2.7 tonnes of Thorium" when the actual number is 27 tonnes.

As for your mercury numbers, you're the one that's way off. this paper sampled US coal for 25 years and came up with a mean mercury value of 0.17ppm. As stated above, US coal has 1.3 ppm U and 3.2 ppm Th. There is 7.6x as much U as Hg, and 18.8x as much Th as Hg.

Besides, the original argument was "Thirdly, the 'idea' that coal emits noticeable radioactivity is a myth from the 1960s/1970s" - I've proven that clearly there is noticeable radiation released on a continuous basis.

If you are too lazy to do any research, then I'm done with you. Continue with vague hand-waving and accusations of bad math and maybe someone will believe you.

Comment: Re:So Germany is not a state? (Score 1) 265

Read the original article again. OLD plants emit as much as 10% - new plants with advanced scrubbers emit no more than 1%. Here's the quote, emphasis mine - search for it:

"Some 99% of flyash is typically retained in a modern power station (90% in some older ones)."

That's not my statistic - if you don't believe it, follow the footnotes in the article.

As for the 50 mg/Nm^3, your limit is higher than ours if the 18.3 mg/Nm^3 is correct. The US burned 850x10^6 tonnes (850x10^9 kg) of coal in the year 2009. Even of we go with the 1% figure nationwide, that's still 11x10^3 kg of uranium and 27x10^3 kg of thorium up the stack. Refer to the quote from the same document, below:

"In the USA, 850 million tonnes of coal was used in 2009 for electricity production. With an average content of 1.3 ppm uranium and 3.2 ppm thorium, US coal-fired electricity generation in that year gave rise to 1100 tonnes of uranium and 2700 tonnes of thorium in coal ash."

This article seems to show that Germany is not so clean after all given the relatively large amount of coal it burns compared to its EU neighbors.

This chart shows Germany using 256 million short tons of coal in 2011. That's 232x10^9 kg. With German coal containing up to 13 ppm of uranium and up to approximately 39 ppm thorium (see the first liked article for the source of those figures), that means:

In 2011 German power plants emitted up to 30x10^3 kg of uranium (232x10^9 x 13ppm x 1%) and up to 90.5x10^3 kg of thorium (232x10^9 kg x 39ppm x 1%).

Note that US coal contains up to 4 ppm uranium while German coal contains up to 13 ppm. From the first article, "US, Australian, Indian and UK coals contain up to about 4 ppm uranium, those in Germany up to 13 ppm ...".

I really can't make it any clearer that ALL coal plants emit fly ash, and because of the vast amounts of coal burnt around the world, that fly ash represents a significant and easily detectable amount of radioactivity (not to mention the chemical toxicity) released into the atmosphere around the plants.

I think I've proven my point with reason and numbers to back it up - all you've contributed is disbelief and scorn.

Comment: Re:So Germany is not a state? (Score 1) 265

I'm sorry you're so stubborn, ignorant, and nationalistic to believe that a mere 1% of the ash generated from burning coal couldn't possibly escape into the atmosphere in the Fatherland. Unless you've got alien-level technology, your German scrubbers are bound by the same physics as those in the US - ~99% efficient is the maximum you can get.

http://www.epa.gov/radiation/t... - 99% efficient

http://www.britannica.com/EBch... - 90% - 99% efficient

http://www.gdnash.com/rocktron... = 99% efficient

Table 3 in this document directly compares particulate matter emission regulations in the US and Germany - as you can see, the average PM emissions for German plants is 50 mg/Nm^3 as opposed to 18.3 mg/Nm^3 for all new large plants in the US as mentioned in this document.

Comment: Your car is broadcasting even as we speak (Score 1) 72

by Muad'Dave (#49391403) Attached to: Ask Slashdot: Identifying a Stolen Car Using Police Camera Databases?

If it's a relatively modern car, than all 5 tires are broadcasting a unique ID every so often - read about TPMS. If you had those IDs, you could set up a simple set of receivers based on SDR dongles to monitor for them. I bet that pretty soon the plate readers mounted on tow trucks, police vehicles, etc will be scanning those IDs as well.

Comment: Re:So Germany is not a state? (Score 1) 265

... all this is filtered out and deposited, and not 'emitted'.

Impossible. As the article I cited states, as much as 10% is EMITTED in an old plant, and as little as 1% in a 'new' plant. You even contradict yourself: "The majourity [sic] of ash ... [is] ... collected and deposited."
Even with 1% escaping, the US still emits TONS of raw radioactive Uranium and Thorium into the atmosphere.

90% of the ash in Germany is transformed into construction material for roads and houses.

This point is also addressed in the cited article:

During combustion the radionuclides are retained and concentrated in the flyash and bottom ash, with a greater concentration to be found in the flyash. The concentration of uranium and thorium in bottom and flyash can be up to ten times greater than for the burnt coal, while other radionuclides such as Pb-210 and K-40 can concentrate to an even greater degree in the flyash. Some 99% of flyash is typically retained in a modern power station (90% in some older ones). While much flyash is buried in an ash dam, a lot is used in building construction. Table 3 gives some published figures for the radioactivity of ash. There are obvious implications for the use of flyash in concrete.

Take a look at table 3 - these figures are for Germany. The first numeric column is Uranium, the next Thorium, and the last Potassium. The figures are Bq/kg.

Germany ash 6-166 3-120 125-742
Germany slag 68-245 76-170 337-1240

According to google, the average cinder block weighs 26-33 lbs (11.8-15 kg). If 75% of a 15kg cinder block's mass is average ash, every single cinder block has 6536 Bq of activity. That's a little shy of 436 BED per block. A cinder block building 20'x20'x10' uses (conveniently) 15 8x8x16 inch blocks in each dimension for each wall, so that's a total of 900 blocks. That's 5,882,625 Bq for the building.

Wikipedia says "In the United States about 131 million tons [118,841,195,700 kg] of fly ash are produced annually by 460 coal-fired power plants. A 2008 industry survey estimated that 43% of this ash is re-used." In the US, that means 51,101,714,151 kg of ash representing an average of 777 Bq/kg (a staggering 39.7 x 10^12 Bq of total activity) being put in close proximity to people per year. That's 2,647,068,793,022 (2.65 x 10^12) BEDs per YEAR, or around 9000 BED/person/yr in the US (round number assuming 300x10^6 people).

Comment: Re:So Germany is not a state? (Score 2) 265

Thirdly, the 'idea' that coal emits noticeable radioactivity is a myth from the 1960s/1970s.

Really? Skip down to table 2 - German coal may not contain a large amount of Uranium, but it does have Radon, Thorium, and Potassium. Please read this post that I wrote using the data from table 2 for US coal.

I seriously doubt there's no U-238 in German coal if there is Ra-226 since they're related via the decay chain, and Table 3 disputes the lack of U in German coal - the ash and slag contain up to 411 Bq/kg of Uranium that has to exist in the unburnt coal.

Even if we ignore the Uranium and go with just the average levels of Th and K, we get a total activity of 435 Bq/kg, which is ~3.5x the lowest US value detailed in my other post. That means 1 kg of average unburnt German coal contains 29 BEDs. When burnt in a 'new' plant (assuming the 1% up-the-flue rule) each burnt 3.45 kg of German coal results in 1 BED (banana equivalent dose, 15 Bq) out the stack. I don't have figures for German coal consumption/year, but that's still quite a lot of fissionable material going up the stack. The US alone emits a minimum of 11 tonnes of U and 2.7 tonnes of Th - that's 70.25 billion (10^9) BEDs best case and 7.025 trillion (10^12) BEDs worst case.

Mass-for-mass, average unburnt German coal is 4.35 times as radioactive as your average banana.

Is it noticeable? Certainly. Is it dangerous? Probably somewhat. Is it worth "The sky is falling" hysteria? No.

Comment: Re:Full benefits & Full responsibility (Score 1) 227

by Muad'Dave (#49370601) Attached to: Nation's Biggest Nuclear Firm Makes a Play For Carbon Credit Cash

1 banana equivalent dose is approximately 15 Bq. Table 2 of this document shows the radioactivity of the coal - let's use the lowest US figures. The note above table 2 says to multiply the U-238 value by 14 and the Th-232 by 10, and add those to the K-40. The results in 124 Bq/kg for US coal, and 1628 Bq/kg for Brazilian coal. That indicates that 1 kg of unburnt US coal is 8.22 BEDs. When burnt, between 1% and 10% of the ash escapes the scrubbers and is emitted into the environment directly (new vs old plants). Assuming that all of the radioactive elements are end up in the ash/slag and NOT directly put up the flue (as would be the case with gaseous radioactive elements such as Ra-226 and Ra-228), 12.1kg of coal when burnt and passed thru 'new plant' scrubbers results in 1 BED out the smokestack. With 850 million tonnes (850x10^9 kq) burned in the US in 2009, that resulted in 70.25 billion BEDs.

If you use the worst-case US figures and an old plant, you end up with 12320 Bq/kg, which is conveniently close to 100x the best-case numbers - 0.121 kg unburnt coal = 1 BED, and 7.025 trillion BEDs up the flue. Interestingly, 121g is close to the mass of the average banana at 150g, so unburnt US 'bad' coal is as radioactive as your average banana, mass-for-mass.

Interesting quotes:

In the USA, 850 million tonnes of coal was used in 2009 for electricity production. With an average content of 1.3 ppm uranium and 3.2 ppm thorium, US coal-fired electricity generation in that year gave rise to 1100 tonnes of uranium and 2700 tonnes of thorium in coal ash.

If we apply the 1% up the stack rule, that means 11 tonnes of U and 2.7 tonnes of Th went out the stack - that's a lot of radioactivity up the flue and a lot of fissionable material wasted.

It is evident that even at 1 part per million (ppm) U in coal, there is more energy in the contained uranium (if it were to be used in a fast neutron reactor) than in the coal itself. If coal had 25 ppm uranium and that uranium was used simply in a conventional reactor, it would yield half as much thermal energy as the coal.

Please check my math.

The intelligence of any discussion diminishes with the square of the number of participants. -- Adam Walinsky

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