Mark Thorson > wrote:
>"Blair P. Houghton" wrote:
>>
>> Mark Thorson > wrote:
>> >"Blair P. Houghton" wrote:
>> >>
>> >> Those look flammable. I'm guessing that they're
>> >> destroyed long before they get near the food.
>> >
>> >Highly branched aliphatic hydrocarbons burn
>> >cleanly. Polycyclic aromatic hydrocarbons
>> >such as napthalene, anthracene, and their
>> >derivatives are much more resistant to
>> >initiation of combustion.
>> >
>> >There's some relevant information he
>> >http://en.wikipedia.org/wiki/Octane_rating
>> >
>> >There will still be uncombusted and
>> >partially combusted molecules which
>> >make it past the flame front.
>> >
>> >But if you choose to continue living in
>> >a fool's paradise, don't let yourself be
>> >dissuaded by me. You can slather yourself
>> >with 10-year-old duck confit for all I care.
>>
>> Okay, first, don't throw the ****ing Wikipedia at anyone
>> and claim you're smart. It's where the truth goes to be
>> buried under petty political nonsense.
>
>Uh huh. All Wikipedia articles were written
>by your enemies, just to make you look like
>an arrogant fool. And somehow they succeeded
>masterfully. :-)

You keep dreaming, some day you might never wake up
and have to face reality.

>> Second, don't use links that don't say anything about the
>> topic you're trying to discuss.
>
>You obviously didn't read the Wikipedia article about
>octane rating, which is directly relevant because it
>discusses the relationship between molecular structure
>and initiation of combustion.
>
>Here, for example, is propane:
>http://www.purchon.com/chemistry/images/propane.gif
>Note that the carbon chain has two ends, where
>combustion is more easy to initiate.

So?

>And here are napthalene and anthracene:
>http://chemed.chem.purdue.edu/genche...aphics/35a.gif
>Note that neither compound has any ends.
>All of the carbon atoms form rings.
>These compounds will be much more difficult
>to combust.

So?

>> Third, that blue flame in the burner is at a very high
>> temperature. Thousands of degrees. The autoignition
>> temperatures of the two molecules you mentioned are much
>> lower than that. Hundreds of degrees. The reaction
>> constant will point to near total combustion.
>
>You don't know squat about combustion.

Try again, hypocrite.

>Propane burns cleanly because it is a small
>molecule, but also because it is linear
>(not a ring or a set of fused rings).

You're a very poorly educated person. Probably a result
of your reliance on the "information" *** folklore in the
wikipedia. My only question is why you haven't added your
new discovery that running LPG tanks dry causes cancer.
I'm betting nobody there will challenge it, because they're
too busy challenging facts and calling experts "trolls".

>While some polycyclic hydrocarbons will be
>burnt in a propane flame, some will pass
>through. Even worse, some will be partially
>burned.

A continuous burn temperature of thousands of degrees
vs. an ignition threshold of hundreds of degrees in a
system designed to burn slowly and fully rather than
explode quickly and imperfectly.

Stop reading that article about octane. It does not apply.

>The napthalene and anthracene core
>structures are not carcinogenic, but many
>of their derivatives are among the most
>powerful carcinogens known, and indeed are
>use in cancer research as reliable initiators
>of cancer.

Then stop eating cooked food, because they're produced in
anything that browns.

>> Fourth, heating the food to a smoking temperature will
>> create more polycyclic aromatic hydrocarbons than could
>> have got past the burner element of a gas grill.
>
>You're just spouting baloney.

Everything you eat must taste like baloney, then.

>In fact, it will
>vary depending on the cleanliness of the gas
>supply. Very dirty gas will indeed be full of
>these molecules. Over time, they will collect
>in the bottom of the propane tank.

Over what length of time? and to what degree? You can
let that tank sit for six months and through simple
thermal effects the disparate molecular constituents of
the fluid may not separate out. I suspect that you're
purely imagining this effect you're describing. I can't
find anywhere that it's described online, but then, I'm
not working to prove your silly hypotheses.

You point something out and I'll show you where you missed
its fallacies.

>Each time
>the tank is filled, new contaminants will be
>introduced.

From what? Another tank, that's been sitting there even
longer than mine has. But, that tank delivers from a
siphon tube that goes to its bottom (so it can siphon
liquid and skip the gas phase). So, if I am the first
person to fill my grill bottle from a depot tank that
has been sitting for, well, years, I will be getting all
the impurities from that tank, leaving the remaining fuel
quite a bit more pure.

And how often would I be that unlucky? How often would
an Amerigas PPX or Blue Rhino bottle have been filled
from such a tank in such a condition? I'm betting they
don't let a load sit more than a couple of weeks before
it's tapped.

We can play this "who gets the backwash?" game all the
way up the chain.

Until you can prove that the aromatics settle out of the
liquid propane, and then that they don't burn, I'm just
not going to worry about it. You've done neither, and
the links you've posted haven't even mentioned those
processes.

>Because the tank pressure is lower
>than at any point in the supply chain from the
>refinery,

Um, bunky, I just described how the siphon works.

These tanks transfer liquid, not gas.

Pressure has nothing to do with it, if the effect
of concentration of impurities in my end system
even exists.

What could be happening is that your tank never gets
its bottom siphoned out, and you never vent it fully,
so every time you fill the tank you add heavy molecules
that never leave, so eventually your tank has nothing but
heavy molecules in its bottom layer.

Nothing to do with pressure.

And you know how you would prevent it from accumulating
to a dangerous concentration?

BY LETTING THE TANK BURN DRY EVERY TIME.

Dumbass.

>these molecules will tend to accumulate
>in the tank. When you run the tank completely
>empty, you force some of them to come out.

Good. Then the next person won't be subjected to the
murderous intent of the negligent propane industry
(these guys must be as bad as the asbestos people)
or your vacuous sophistry.

>> This will
>> occur on a charcoal grill, or in your frying pan. But the
>> world will not be giving up on the Maillard reaction in
>> our lifetimes.
>>
>> Your duck's discomfiture is your own damned problem.
>
>Let me guess. You woke up with a nasty
>hangover this morning.

You keep guessing, some day you'll figure out why you
walk into fan blades.

--Blair