whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit

Wash with plenty of hot water and alkaline solution then pipe in carbon
monoxide from vehicle tailpipe.

Sal

wrote in message
...
whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit

sal wrote:

Wash with plenty of hot water and alkaline solution then pipe in carbon
monoxide from vehicle tailpipe.

Sal

wrote in message
...

whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit

Surely you're joking, Sal.

Combined 12% to 75% with air, CO constitutes an EXPLOSIVE MIXTURE.
http://www.engineeringtoolbox.com/ex...its-d_423.html

You got something against dbur177?

--Winston

Christopher Tidy wrote:

Isn't CO harder to acquire now that catalytic convertors are common?

Actually suicide by car is down, as far as sitting in garage with engine running.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

Winston wrote:
sal wrote:

Wash with plenty of hot water and alkaline solution then pipe in
carbon monoxide from vehicle tailpipe.

Sal

wrote in message
...

whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit


Surely you're joking, Sal.

Combined 12% to 75% with air, CO constitutes an EXPLOSIVE MIXTURE.
http://www.engineeringtoolbox.com/ex...its-d_423.html

You got something against dbur177?

Isn't CO harder to acquire now that catalytic convertors are common?

Chris

Christopher Tidy wrote:

Isn't CO harder to acquire now that catalytic convertors are common?

Rumor has it the cat converter reduces CO by 99%.

I'm very literal though. The phrase "...then pipe in carbon monoxide
from vehicle tailpipe" cannot be reasonably interpreted to mean
"... then pipe in gas largely scrubbed of carbon monoxide from vehicle
tailpipe". Even that answer is so dangerous and ill advised that a
wise person might call it "not even wrong".

--Winston

Wes writes:

Christopher Tidy wrote:

Isn't CO harder to acquire now that catalytic convertors are common?

Actually suicide by car is down, as far as sitting in garage with engine running.


Can't afford the price of gas.


--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

On 2008-09-25, David Lesher wrote:
Wes writes:
Christopher Tidy wrote:
Isn't CO harder to acquire now that catalytic convertors are common?
Actually suicide by car is down, as far as sitting in garage with engine running.
Can't afford the price of gas.

Plus, garages are getting foreclosed along with homes.

--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

sal wrote:
Wash with plenty of hot water and alkaline solution then pipe in carbon
monoxide from vehicle tailpipe.

Sal

wrote in message
...
whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit



If this is a fuel oil tank you don't have to purge it. Just fill it and
weld. Don't leave space for air anywhere near the weld site. The fuel
will not ignite because of the lack of air. The mix is so rich it won't
ignite.

If you doubt this being true then I suggest you don't EVER drive any
vehicle with an in tank fuel pump. They run fuel through the motor and
brushes to keep them cool and lubed.

--
Steve W.

The most reliable way is to steam it out, preferably for about half an
hour.

Incidently, carbon monoxide is flamable so that is NOT what you are trying
to get out of a vehicle tailpipe.
What you are after is carbon dioxide. Carbon dioxide will not suport
combustion, and is dangerous to you only because it displaces the oxygen in
the surrounding air. Carbon monoxide is poisonous. It replaces the oxygen in
you blood and the cells in your body die due to lack of oxygen.





"sal" wrote in message
...
Wash with plenty of hot water and alkaline solution then pipe in carbon
monoxide from vehicle tailpipe.

Sal

wrote in message
...
whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit

On Wed, 24 Sep 2008 20:05:48 -0400, the infamous Wes
scrolled the following:

Christopher Tidy wrote:

Isn't CO harder to acquire now that catalytic convertors are common?

Actually suicide by car is down, as far as sitting in garage with engine running.

It's no wonder, with gas prices the way they are.

--
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all
progress depends on the unreasonable man.
-- George Bernard Shaw

On Wed, 24 Sep 2008 14:34:56 -0700 (PDT), wrote:

whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit

I prefer to fill them with water to about an inch of the weld. Second
option purge with liquid CO2, get a tank with dip tube or turn bottle
upside down. the C02 will not support combustion and the -100 degrees
cools the oil so you have little vapor to ignite.

Weld at your own risk.

Thank You,
Randy

Remove 333 from email address to reply.

What you are after is carbon dioxide. Carbon dioxide will not suport
combustion, and is dangerous to you only because it displaces the oxygen
in the surrounding air.

I use CO2 welding, soldering, or brazing gas tanks occasionally. If you
don't have a bottle handy buy some dry ice at Baskin Robbins and drop it in,
leave it long enough to melt with tape loosely covering the holes, so gas
pressure can escape as it melts, and when heat is applied.
The preferred method would be to solder using a large electric, or coppers
heated some distance away and relayed by an assistant.
Even better, get the assistant to do it lol.
--
Stupendous Man,
Defender of Freedom, Advocate of Liberty

"Steve W." writes:


If this is a fuel oil tank you don't have to purge it. Just fill it and
weld. Don't leave space for air anywhere near the weld site. The fuel
will not ignite because of the lack of air. The mix is so rich it won't
ignite.

The pipeline crew would weld patches onto 3.5 million gallon
gasoline/fuel oil tanks regularly. The usual reason was someone had shot
a hole in the tank. The SOP was to pound a plug into it and let the
outside dry, then weld a plate over top of it.

The rules required the weld site to be X feet below the top of the
product; i.e. submerged on the inside. I can't recall how many feet
X was.



--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

C'mon, guys....it's not the CO. tailpipe values for a properly running
engine with good cat are 1% or less O2. No matter the composition,
pumping tailpipe gas into the tank will purge any potentially
combustible mixture.
JR
Dweller in the cellar

Winston wrote:

sal wrote:

Wash with plenty of hot water and alkaline solution then pipe in
carbon monoxide from vehicle tailpipe.

Sal

wrote in message
...

whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit


Surely you're joking, Sal.

Combined 12% to 75% with air, CO constitutes an EXPLOSIVE MIXTURE.
http://www.engineeringtoolbox.com/ex...its-d_423.html

You got something against dbur177?

--Winston

--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
Doubt yourself, and the real world will eat you alive
The world doesn't revolve around you, it revolves around me
No skeletons in the closet; just decomposing corpses
--------------------------------------------------------------
Dependence is Vulnerability:
--------------------------------------------------------------
"Open the Pod Bay Doors please, Hal"
"I'm sorry, Dave, I'm afraid I can't do that.."

JR North wrote:

C'mon, guys....it's not the CO. tailpipe values for a properly running
engine with good cat are 1% or less O2. No matter the composition,
pumping tailpipe gas into the tank will purge any potentially
combustible mixture.
JR
Dweller in the cellar

JR, Puleeze.

Car exhaust is just not safe. Other suggestions in this thread are much more
compatible with continued breathing.

If dburl177 wants to purge with CO2 or water or argon in a well ventilated,
above ground work area, that'll work just fine. Pardon the sensitivity but
I lost a friend a couple months ago due to car exhaust. Granted, he made
an informed decision and hopefully passed away peacefully.

I don't think that was the OP's goal though.

--Winston

On Wed, 24 Sep 2008 14:34:56 -0700 (PDT), wrote:

whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit

Heating Oil AKA #2 Distillate AKA Diesel Fuel? That stuff is very
difficult to light off in a tank like that - look how hard you have to
work to make it light when you DO want it to burn... A simple purge
of the tank with any handy and appropriate inert gas will work.

Carbon Dioxide is the easiest and cheapest, either from dry ice or
cryo liquid (if you have it) or a bottle. Nitrogen works if you have
a separator system, or from a compressed bottle, or from liquid
nitrogen. Or Argon or Argon/CO2 welding mix...

It's the more volatile things like gasoline you have to be more
paranoid with your precautions - and even then you need free fumes and
oxygen to make it go BOOM! If the tank has no free oxygen in it (only
gasoline and gasoline vapors) and you don't let liquid fuel or free
vapors out to mix with atmospheric oxygen, no go BOOM!

Steam would even work if you provided a continuous low pressure
supply to purge air.

(Don't restrict the vent with a check valve, the steam stops and the
tank implodes. Fun to watch on 'Mr. Wizard' or 'Bill Nye the Science
Guy' as a demonstration, not so fun on /your/ gas tank.)

NOTE: Even though you purge the tank, you DO NOT do this alone.
Have someone stand Fire Watch behind you as you weld, with a big-ass
fire extinguisher or two (that they know how to work!) at the ready.
With the mask on, you can't see when the fire starts at the filler
neck because it isn't in your field of view.

And tell a third worker nearby (or your neighbor if this is at home)
what you are doing. "If you hear us yelling FIRE! we aren't joking -
call 9-1-1 First, investigate second."

And have a few more extinguishers strategically placed along the
retreat routes, this is one of those times you can never have too
many. So once you've turned off and dropped the torch and gotten back
from the fire, you can join in the festivities. You'll have the
protective welding apparel on so you can safely get a bit closer.

-- Bruce --

David Lesher wrote:
"Steve W." writes:


If this is a fuel oil tank you don't have to purge it. Just fill it and
weld. Don't leave space for air anywhere near the weld site. The fuel
will not ignite because of the lack of air. The mix is so rich it won't
ignite.

The pipeline crew would weld patches onto 3.5 million gallon
gasoline/fuel oil tanks regularly. The usual reason was someone had shot
a hole in the tank. The SOP was to pound a plug into it and let the
outside dry, then weld a plate over top of it.

The rules required the weld site to be X feet below the top of the
product; i.e. submerged on the inside. I can't recall how many feet
X was.




Last I knew it was based on product type in the tank.

On a small pinhole leak you can use plain Ivory soap. The fats used
making the soap will react with the petroleum and swell to seal the leak.

--
Steve W.
Near Cooperstown, New York

I'm not suggesting he stick the pipe in his mouth.....yet.
JR
Dweller in the cellar


Winston wrote:
JR North wrote:

C'mon, guys....it's not the CO. tailpipe values for a properly running
engine with good cat are 1% or less O2. No matter the composition,
pumping tailpipe gas into the tank will purge any potentially
combustible mixture.
JR
Dweller in the cellar


JR, Puleeze.

Car exhaust is just not safe. Other suggestions in this thread are much
more
compatible with continued breathing.

If dburl177 wants to purge with CO2 or water or argon in a well ventilated,
above ground work area, that'll work just fine. Pardon the sensitivity but
I lost a friend a couple months ago due to car exhaust. Granted, he made
an informed decision and hopefully passed away peacefully.

I don't think that was the OP's goal though.

--Winston

--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
Doubt yourself, and the real world will eat you alive
The world doesn't revolve around you, it revolves around me
No skeletons in the closet; just decomposing corpses
--------------------------------------------------------------
Dependence is Vulnerability:
--------------------------------------------------------------
"Open the Pod Bay Doors please, Hal"
"I'm sorry, Dave, I'm afraid I can't do that.."

On Thu, 25 Sep 2008 10:11:46 -0700, Winston
wrote:

JR North wrote:

C'mon, guys....it's not the CO. tailpipe values for a properly running
engine with good cat are 1% or less O2. No matter the composition,
pumping tailpipe gas into the tank will purge any potentially
combustible mixture.
JR
Dweller in the cellar

JR, Puleeze.

Car exhaust is just not safe. Other suggestions in this thread are much more
compatible with continued breathing.

If dburl177 wants to purge with CO2 or water or argon in a well ventilated,
above ground work area, that'll work just fine. Pardon the sensitivity but
I lost a friend a couple months ago due to car exhaust. Granted, he made
an informed decision and hopefully passed away peacefully.

I don't think that was the OP's goal though.

--Winston

Kind of interesting to watch this thread as pumping engine exhaust
into fuel tanks is exactly what many ships that transport hydrocarbon
liquids do and have done for many years.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Bruce in Bangkok wrote:

(...)

Kind of interesting to watch this thread as pumping engine exhaust
into fuel tanks is exactly what many ships that transport hydrocarbon
liquids do and have done for many years.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Bruce, can you help me understand your point please?

I can think of a couple other things routinely done by professionals
with acceptable safety, that probably shouldn't be done by untrained
individuals using casually assembled equipment. I am sure you can
as well.

I for example, being one of those untrained individuals with casually
assembled equipment probably shouldn't put together a liquid fueled
rocket. I realize that amateurs have done that.. (5320 Google hits
just now). I'm just saying that I would be asking for trouble by
doing so, without first gaining significant knowledge, much of it
safety - related.

I could, conceivably drive my car in front of a speeding train to
rehearse for an amateur stunt movie. Would that be a wise thing for
me to do? Nuh uh.

http://www.metacafe.com/watch/yt-IlP...g/train_wreck/

Advising someone to do something in a risky way, particularly when
there are several much safer ways to do it, is irresponsible.

If you are just yanking me, that's cool.

I'm just concerned about those folks who are as literal and trusting
as I am.

--Winston

On Fri, 26 Sep 2008 00:13:18 -0700, Winston
wrote:

Bruce in Bangkok wrote:

(...)

Kind of interesting to watch this thread as pumping engine exhaust
into fuel tanks is exactly what many ships that transport hydrocarbon
liquids do and have done for many years.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Bruce, can you help me understand your point please?

I can think of a couple other things routinely done by professionals
with acceptable safety, that probably shouldn't be done by untrained
individuals using casually assembled equipment. I am sure you can
as well.

I for example, being one of those untrained individuals with casually
assembled equipment probably shouldn't put together a liquid fueled
rocket. I realize that amateurs have done that.. (5320 Google hits
just now). I'm just saying that I would be asking for trouble by
doing so, without first gaining significant knowledge, much of it
safety - related.

I could, conceivably drive my car in front of a speeding train to
rehearse for an amateur stunt movie. Would that be a wise thing for
me to do? Nuh uh.

http://www.metacafe.com/watch/yt-IlP...g/train_wreck/

Advising someone to do something in a risky way, particularly when
there are several much safer ways to do it, is irresponsible.

If you are just yanking me, that's cool.

I'm just concerned about those folks who are as literal and trusting
as I am.

--Winston


Rather a complex response to a simple exchange.

The poster says "Car exhaust is just not safe. Other suggestions in
this thread are much more..."

I simply point that it isn't intrinsically unsafe as ships have been
doing it for years and, probably will continue to do it as it is the
cheapest and easiest method so far developed.

Now, if you really think it is necessary to qualify the statement with
something like "I know youse guys are a bunch of idiotic stumble bums
that don't enough sense to come in out of the rain and are so fumble
fingered that you can't hit you ass with both hands", just let me
know.

Until you do I'll continue to consider the denizens of this group as
normally adept craftsmen.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Bruce in Bangkok wrote:

(...)

Rather a complex response to a simple exchange.

Apt though, Yes?

The poster says "Car exhaust is just not safe. Other suggestions in
this thread are much more..."

Quoting the OP, verbatim:
"whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit"


Quoting Sal, the first responder (pun intended):
"Wash with plenty of hot water and alkaline solution then pipe in carbon
monoxide from vehicle tailpipe."

I simply point that it isn't intrinsically unsafe as ships have been
doing it for years and, probably will continue to do it as it is the
cheapest and easiest method so far developed.

Ships have not been displacing air in fuel tanks using CO.
Not intentionally anyway.
We would have heard, perhaps individually, in the first person.

Note that I didn't say anything about use of CO2.

My point was that:
"Combined 12% to 75% with air, CO constitutes an EXPLOSIVE MIXTURE."
Grumpy mentioned that it is poisonous, as well.

Now, if you really think it is necessary to qualify the statement with
something like "I know youse guys are a bunch of idiotic stumble bums
that don't enough sense to come in out of the rain and are so fumble
fingered that you can't hit you ass with both hands", just let me
know.

Jeeze Bruce, who implied that?

Like all newsgroups, RCM comprises a wide variety of individuals of
varying experience and capability. I like to think that they self-
select for many desirable traits, among them, intelligence, a thirst
for knowledge and a hands-on attitude. They, with very few exceptions
have earned my admiration and respect. I hope to continue learning
from all these smart people.

Until you do I'll continue to consider the denizens of this group as
normally adept craftsmen.

Doubtlessly, most are, on average. Some are geniuses. Some, (myself
included) struggle on, using the FSM's meager gifts as well as
they can.
At best, it's a mistake to tell people something that is likely to
hurt them, particularly if much safer methods are available.

Level check...Test TEST One Two. Is this thing on?

--Winston

"Winston" wrote in message
...
Bruce in Bangkok wrote:

(...)

Rather a complex response to a simple exchange.

Apt though, Yes?

The poster says "Car exhaust is just not safe. Other suggestions in
this thread are much more..."

Quoting the OP, verbatim:
"whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit"


Quoting Sal, the first responder (pun intended):
"Wash with plenty of hot water and alkaline solution then pipe in
carbon
monoxide from vehicle tailpipe."

I simply point that it isn't intrinsically unsafe as ships have been
doing it for years and, probably will continue to do it as it is the
cheapest and easiest method so far developed.

Ships have not been displacing air in fuel tanks using CO.
Not intentionally anyway.
We would have heard, perhaps individually, in the first person.

Note that I didn't say anything about use of CO2.

My point was that:
"Combined 12% to 75% with air, CO constitutes an EXPLOSIVE MIXTURE."
Grumpy mentioned that it is poisonous, as well.

CO is used as fuel in heat-treating furnaces. If you want to end it all,
it's a fair choice, if not a good one.

--
Ed Huntress

Ed Huntress wrote:

CO is used as fuel in heat-treating furnaces. If you want to end it all,
it's a fair choice, if not a good one.

Dry nitrogen. Way better. I'm just sayin.

--Winston

"Winston" wrote in message
...
Ed Huntress wrote:

CO is used as fuel in heat-treating furnaces. If you want to end it all,
it's a fair choice, if not a good one.

Dry nitrogen. Way better. I'm just sayin.

--Winston

For blowing yourself up, or for heat-treating steel? g

--
Ed Huntress

On Fri, 26 Sep 2008 13:30:05 -0700, Winston wrote:

Bruce in Bangkok wrote:

(...)

Rather a complex response to a simple exchange.

Apt though, Yes?

The poster says "Car exhaust is just not safe. Other suggestions in
this thread are much more..."

Quoting the OP, verbatim:
"whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit"


Quoting Sal, the first responder (pun intended):
"Wash with plenty of hot water and alkaline solution then pipe in carbon
monoxide from vehicle tailpipe."



Wash with the hot water/degreaser/alkaline cleaner leave it vented and then
get on with the bloody welding fergossakes! A clean oil tank/gasoline
tank/propane tank is _not_ an explosion hazard. There may be the odd flicker
of flame. But there is that if you weld near painted metal and no-one gets
their shorts all knotted up over that do they?


Mark Rand
RTFM

Ed Huntress wrote:
"Winston" wrote in message
...

Ed Huntress wrote:


CO is used as fuel in heat-treating furnaces. If you want to end it all,
it's a fair choice, if not a good one.

Dry nitrogen. Way better. I'm just sayin.

--Winston


For blowing yourself up, or for heat-treating steel? g

I don't know what you are talking about.



--Winston

Mark Rand wrote:

Wash with the hot water/degreaser/alkaline cleaner leave it vented and then
get on with the bloody welding fergossakes! A clean oil tank/gasoline
tank/propane tank is _not_ an explosion hazard. There may be the odd flicker
of flame. But there is that if you weld near painted metal and no-one gets
their shorts all knotted up over that do they?

Was it Mark Twain who said that it is possible to have an enjoyable
conversation only if all participants are unfamiliar with the subject?

Thanks for ruining a perfectly enjoyable conversation, you weasle.



--Winston

On Fri, 26 Sep 2008 13:30:05 -0700, Winston
wrote:

Bruce in Bangkok wrote:

(...)

Rather a complex response to a simple exchange.

Apt though, Yes?

The poster says "Car exhaust is just not safe. Other suggestions in
this thread are much more..."

Quoting the OP, verbatim:
"whats the best way to purge so that a welding spark wont blow me yup
kapow not ready to die today may a eathquake or flood torado no
blown to out of orbit"


Quoting Sal, the first responder (pun intended):
"Wash with plenty of hot water and alkaline solution then pipe in carbon
monoxide from vehicle tailpipe."

I simply point that it isn't intrinsically unsafe as ships have been
doing it for years and, probably will continue to do it as it is the
cheapest and easiest method so far developed.

Ships have not been displacing air in fuel tanks using CO.
Not intentionally anyway.
We would have heard, perhaps individually, in the first person.

Winston, ships have been using flue gas to provide an inert atmosphere
in their tanks for years. Here are a couple of references:
First a long, rather drawn out discussion about ships:
http://www.spectacle.org/196/gross.html

Second, a for sale advert which shows a vessel listed for sale with
the inert gas system:
http://www.omccthailand.com/webboard...=shp03&No=1635

In short, you are making an assertion that I am wrong with no proof,
while I am showing you how wrong you are.

I assume that as you don't know what you are talking about when you
attempt to refute my statements you probably don't know what you are
talking the rest of the time and it seems ridicules to engage in a
debate with a fool. So as far as I am concerned the contest is over.
Please feel free to feel that you have "won" if it strokes your ego.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Bruce in Bangkok wrote:

Winston, ships have been using flue gas to provide an inert atmosphere
in their tanks for years. Here are a couple of references:
First a long, rather drawn out discussion about ships:
http://www.spectacle.org/196/gross.html

Flue gas has almost no CO (70 - 160 ppm) It is a mixture of about
94% nitrogen and carbon dioxide and a little oxygen.

http://www.habmigern2003.info/19_flue-gas-contents.html

I think we can agree that flue gas, popularly used to displace air in
the fuel tanks of ships is non-flammable.

Can we also agree that that the carbon monoxide (CO) component of
exhaust gas as emitted from the tailpipes of most pre-1975 cars is
both poisonous and flammable?

Thassall I was saying. Sorry to ruffle ya.

--Winston

On Sep 26, 9:48*pm, Winston wrote:

Flue gas has almost no CO (70 - 160 ppm) It is a mixture of about
94% nitrogen and carbon dioxide and a little oxygen.


--Winston

I'm a bit curious as to how the combustion process has increased the
nitrogen percentage, from about 80% in the air going in to the 94% of
the flue gas.

John Martin

On Fri, 26 Sep 2008 22:08:48 -0700, Bruce L. Bergman
wrote:

On Fri, 26 Sep 2008 20:46:48 -0700 (PDT), John Martin
wrote:
On Sep 26, 9:48*pm, Winston wrote:

Flue gas has almost no CO (70 - 160 ppm) It is a mixture of about
94% nitrogen and carbon dioxide and a little oxygen.

I'm a bit curious as to how the combustion process has increased the
nitrogen percentage, from about 80% in the air going in to the 94% of
the flue gas.

You use all the oxygen in the air for combustion, and don't generate
all that much carbon dioxide in return. And you generate water vapor
(H2O), that doesn't count as a gas. That's how the nitrogen content
increases, because the other stuff decreases or converts.

Now note that the "flue gas" they are using is from a Diesel engine,
NOT Gasoline. Or they could be burning bunker oil in a big Wartsilla
bazillion-CID marine diesel if they preheat it first.

Gasoline engines built pre-catalyst can have significant CO in the
exhaust (not to mention some unburned gasoline ftrom incomplete
combustion at idle) and that's what has everyone here worried enough
to NOT use it as a blanket suggested method of purging a tank.

-- Bruce --


Actually. Even with a somewhat rich running, non catalyst petrol engine. The
exhaust won't support combustion even of hydrocarbons. The oxygen depletion
takes care of that. The 1-4% CO is poisonous and the unburned gasoline is
flammable, but they won't support combustion.

Indeed. If the modern catalyzed engine is cold, the catalyst is going to have
no effect on the CO output of the engine.

As I implied before. JFDI :-)


Mark Rand
RTFM

On Fri, 26 Sep 2008 22:11:41 -0700, Winston
wrote:

John Martin wrote:
On Sep 26, 9:48 pm, Winston wrote:

Flue gas has almost no CO (70 - 160 ppm) It is a mixture of about
94% nitrogen and carbon dioxide and a little oxygen.


--Winston


I'm a bit curious as to how the combustion process has increased the
nitrogen percentage, from about 80% in the air going in to the 94% of
the flue gas.

John Martin

That is a good question. Any Chem E's want to help us with an answer?

--Winston

Chemist, not Chem E., I assumed complete combustion with 78% N2, 21%
O2, and 1% other gas with a CH2.2 hydrocarbon to only H2O and CO2. If
you condense the water, I get 80% N2, 19% CO2, and 1% other. Plus the
water doesn't condense in the flue gas, so that'd make it 74% N2, 18%
CO2, 8% H2O, and 1% other. 1% rounding error. This also discounts
CO, NOx, unburned fuel, etc. I don't know how you'd get 94% N2.

You lose the O2, but get CO2, mole for mole. The only loss in mass is
the O2 to H2O, and only if it condenses. Otherwise, you gain the mass
of the fuel. I figured it on mass, not volume. Gas volume is 22.4 L
/ g-mole at STP.

Pete Keillor

Pete Keillor wrote:


(...)
I don't know how you'd get 94% N2.

(...)

Thanks Pete.

I put that very clumsily by adding the fractions of N2 and CO2 to indicate
how much of the flue gas becomes completely non-flammable.

Nitrogen approx. 78 to 80%
Carbon Dioxide approx. 12 - 14%
Oxygen: 2 - 6%

--Winston

Larry Jaques wrote:

Actually suicide by car is down, as far as sitting in garage with engine running.

It's no wonder, with gas prices the way they are.


If you can afford to kill yourself burning gas in the garage, maybe your life isn't so
bleek.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller