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Anatomy of fire


John Martin

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Correct me where I am wrong, I'm trying to put together a article so to speak on the anatomy of fire.

Three Parts to a Fire. Image thanks to wikipedia. Could not make a decent triangle.

180px-Fire_triangle.svg.png

A fire exists only as long as long as there is oxygen a fuel source, and heat. Fire is an oxidation process -- just like scale on a piece that you're working with -- that releases energy from the fuel in the form of light, heat, and smoke. The bi-product is ash and carbon dioxide. (Note: It is not recommend that you stare at the bright flame of a fire.) Once going fires can maintain their own heat by the release of energy in the form of heat provided there is a readily available or continuous supply of oxygen and fuel. Fire can be extinguished by removing one or two or all three of the elements of the triangle seen above.


EDIT: By Admin, then I just took the rest out.


Flame Color Chart
Red
o Dullish Red: 1300

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Smoke is unburned gas, particulate matter, etc


Phosphorus Handling and storage

Keep in a tightly closed container, stored in a cool, dry, ventilated area. Protect against physical damage. Isolate from incompatible substances. Protect from light. Avoid dust formation and control ignition sources. Employ grounding, venting and explosion relief provisions in accord with accepted engineering practices in any process capable of generating dust and/or static electricity. Empty only into inert or non-flammable atmosphere. Emptying contents into a non-inert atmosphere where flammable vapors may be present could cause a flash fire or explosion due to electrostatic discharge. Containers of this material may be hazardous when empty since they retain product residues (dust, solids); observe all warnings and precautions listed for the product.

Phosphorus Disposal Considerations

Whatever cannot be saved for recovery or recycling should be
handled as hazardous waste
and sent to a RCRA approved waste facility. Processing, use or contamination of this product may change the waste management options. State and local disposal regulations may differ from federal disposal regulations. Dispose of container and unused contents in accordance with federal, state and local requirements.

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Smoke is a by-product. Unburned gases, etc.

The three mentioned parts combine to create what we called in the fire service the "fire tetrahedron" or something like that. Remove any of the 3 required components from the equation, and the flame disappears. Thus the importance to firefighters.

My advice is to leave the phosphorus alone, save the fireworks for the professionals.

my $.02, for what it's worth

aaron

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Smoke is pretty complex stuff, really. It is an aerosol (suspension of ultra-fine solid or liquid particles in a gaseous medium), and its chemical makeup varies wildly with whatever fuel is being oxidised to create the smoke.

From wood, it's usually carbon dioxide, carbon monoxide, native carbon, water vapour, methanol, and heavier organics such as may be found in creosote and turpentine. You can see evidence of this when a smoky fire starts to burn cleaner. The smoke is being released as a by-product of combustion (spell it right if you're posting an informative article), and subsequently being consumed as a fuel.

From metals burning, it's usually just the metal oxide itself and absolutely not to be breathed in (most famously for zinc, but the same goes with all metal oxide vapours).

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  • 3 weeks later...
Remove any of the 3 required components from the equation, and the flame disappears. Thus the importance to firefighters.


a useful simplification for firefighters, the general public and children
it might be more useful to consider combustion instead of fire

Combustion or burning is a complex sequence of exothermic chemical reactions between a fuel and an oxidant


while its useful to keep most fuels below an energy level where they will ignite
heat is a by product of fire, not necessarily a limiting factor to a chemical chain reaction that is supplying its own heat

accompanied by the production of heat or both heat and light in the form of either a glow or flames.

Direct combustion by atmospheric oxygen is a reaction mediated by radical intermediates. The conditions for radical production are naturally produced by thermal runaway, where the heat generated by combustion is necessary to maintain the high temperature necessary for radical production.


atmospheric oxygen isn't even necessary, take for instance thermite
aluminum is the fuel, and rust the oxygen source. Or an oxy-fuel say hydrogen peroxide, at a 70–98+% concentration its a monopropellant the storage temperature of the fuel is immaterial as soon as the flame front arrives. You can't "remove" the heat.

Then there is another shade, autoignition, in say a diesel engine, or fire piston.
a change in pressure produces the heat for ignition

none of these shades of understanding violate the tripodtetrahedron
just strech how most folks interpret it. Heating to an ignition point in particular can be nearly instantaneous and next to impossible to "remove"

;)
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sorry, the perfect example a little closer to home just occurred to me

an acetylene generator

Acetylene pressure at the generator, in distribution lines and at the point of use
must not exceed 15 psi gauge pressure due to the possibility of an explosion

auto ignition via the Adiabatic process can occur (like a fire piston) at pressure above that

you might also find Adiabatic flame temperature another interesting portal to combustion thermodynamics ;)

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Ice Czar,

Not trying to attack your posts, as the advanced information on combustion and the like are helpful to the original thrust of the thread. Just consider that for link purposes, wikipedia can be changed by anyone, thus, there may some inaccuracies in the definitions. Links to a more solid platform of definitions may be in order.

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IForgeIron has a wikipedia of blacksmithing and metalworking as part of the site. Any member can add to the resource. Usually it is better to make the addition of more information below the existing post. Original material please, as YOU are a blacksmith and should be able to define the term in your own words. Besides, we understand blacksmith to blacksmith much better than some high tech explanation that we need to look words to figure out what is being said.
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Glenn, I noticed the wiki appear a while back, and haven't seen much happening with it yet. One thing I thought it might work well for would be rough drafts of blue prints. In case people don't have a good place of their own to work on them. Just thought I might throw that out there. My apologies for thread hi-jacking..

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Just to clear up what I posted, the wikipedia links are for the wiki available on the web and accessible to anyone that wants to edit or delete information. I have heard nasty rumors that a lot of misinformation is spread using this medium.

Perhaps links from Webster's dictionary, or a more accredited site is what I was trying to get at. Sorry for any confusion this may cause.

On another note, I wish more people would post on the wiki available here at IFI. Will be a great resource for anyone interested in blacksmithing!! (or those just learning!)

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generally speaking the shenanigans possible at wikipedia occur over social issues or people, the hard sciences are generally reliable. If you have any doubt you can veiw a comparative history of an article. The ability for someone to make corrections, additions, or a new article is the great strength of any wiki, but verifying information is easy when you have a lexicon of specific search queries. There are also generally external links, cross references with wiki articles and a self supporting network of logic between related articles (at least in the sciences :P )

IMO traditional "reference" materials are an endangered species, consider

Wikipedia - Wikipedia, the free encyclopedia

As of November 2007, Wikipedia had approximately 9.1 million articles in 253 languages, comprising a combined total of over 1.41 billion words for all Wikipedias. The English Wikipedia edition passed the 2,000,000 article mark on September 9, 2007, and as of December 17 it had over 2,131,000 articles consisting of over 927,000,000 words.[1] Wikipedia's articles have been written collaboratively by volunteers around the world and the vast majority of them can be edited by anyone with access to the Internet. Having steadily risen in popularity since its inception,[3] it currently ranks among the top ten most-visited websites worldwide.[7]

Critics have questioned Wikipedia's reliability and accuracy, citing its open nature.[8] The criticism is centered on its susceptibility to vandalism, such as the insertion of profanities or random letters into articles, and the addition of false or unverified information;[9] uneven quality, systemic bias and inconsistencies;[10] and for favoring consensus over credentials in its editorial process.[11] Scholarly work suggests that vandalism is generally short-lived.[12][13]


anything on the web needs verification, and the application of critical thinking
but odds are the thermodynamics section of wikpedia is "safe" :P

as far as the PSI ratings that wasnt from wikipedia, I grabbed it off a state reg (Penn?) its also lower in some countries. Pressure is just one variable, ambient temperature would be another.

Acetylene generators are also slightly different from Acetylene storage as its an ongoing chemical reaction of calcium carbide and H2O
whereas storage employs its being dissolved into acetone isolating it from O2 forestalling decomposition, the acetone in turn is within a matrix of porous material which limits the free volume of the tank controlling and cooling any thermal decomposition

http://www.depweb.state.pa.us/deepminesafety/lib/deepminesafety/training/ppt/oxyacetylene.ppt

explosive range is 3.0 to 93%
needs only 10% oxygen to ignite
it is an unstable gas, will violently decompose when in a pure state above 15 psi
Auto-ignition temperature is 763-825 F, this means acetylene reaches 30 psi in a free state. it can explode by itself without a spark or flame being present
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