Purple color comes from airfloat ash being drown with the gas. Potassium in the ash gives a pink/purple flame reaction.
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Good Morning yĀ“all. Found this that could be of some help.
Flame
Flames of charcoal
Laminar flame of a burning candle
A flame (from Latin flamma) is the visible, gaseous part of a fire. It is caused by a highly exothermic reaction taking place in a thin zone. Very hot flames are hot enough to have ionized gaseous components of sufficient density to be considered plasma.
Mechanism
Color and temperature of a flame are dependent on the type of fuel involved in the combustion, as, for example, when a lighter is held to a candle. The applied heat causes the fuel molecules in the candle wax to vaporize. In this state they can then readily react with oxygen in the air, which gives off enough heat in the subsequent exothermic reaction to vaporize yet more fuel, thus sustaining a consistent flame. The high temperature of the flame causes the vaporized fuel molecules to decompose, forming various incomplete combustion products and free radicals, and these products then react with each other and with the oxidizer involved in the reaction. Sufficient energy in the flame will excite the electrons in some of the transient reaction intermediates such as the Methylidyne radical (CH) and Diatomic carbon (C2), which results in the emission of visible light as these substances release their excess energy (see spectrum below for an explanation of which specific radical species produce which specific colors). As the combustion temperature of a flame increases (if the flame contains small particles of unburnt carbon or other material), so does the average energy of the electromagnetic radiation given off by the flame.
Other oxidizers besides oxygen can be used to produce a flame. Hydrogen burning in chlorine produces a flame and in the process emits gaseous hydrogen chloride (HCl) as the combustion product.[2] Another of many possible chemical combinations is hydrazine and nitrogen tetroxide which is hypergolic and commonly used in rocket engines. Fluoropolymers can be used to supply fluorine as an oxidizer of metallic fuels, e.g. in the magnesium/teflon/viton composition.
The chemical kinetics occurring in the flame are very complex and involves typically a large number of chemical reactions and intermediate species, most of them radicals. For instance, a well-known chemical kinetics scheme, GRI-Mech, uses 53 species and 325 elementary reactions to describe combustion of biogas.
There are different methods of distributing the required components of combustion to a flame. In a diffusion flame, oxygen and fuel diffuse into each other; where they meet the flame occurs. In a premixed flame, the oxygen and fuel are premixed beforehand, which results in a different type of flame. Candle flames (a diffusion flame) operate through evaporation of the fuel which rises in a laminar flow of hot gas which then mixes with surrounding oxygen and combusts.
Flame color
Spectrum of the blue (premixed, i.e., complete combustion) flame from a butane torch showing molecular radical band emission and Swan bands. Note that virtually all the light produced is in the blue to green region of the spectrum below about 565 nanometers, accounting for the bluish color of sootless hydrocarbon flames.
Different flame types of a Bunsen burner depend on oxygen supply. On the left a rich fuel with no premixed oxygen produces a yellow sooty diffusion flame; on the right a lean fully oxygen premixed flame produces no soot and the flame color is produced by molecular radicals, especially CH and C2 band emission.
Flame color depends on several factors, the most important typically being black-body radiation and spectral band emission, with both spectral line emission and spectral line absorption playing smaller roles. In the most common type of flame, hydrocarbon flames, the most important factor determining color is oxygen supply and the extent of fuel-oxygen pre-mixing, which determines the rate of combustion and thus the temperature and reaction paths, thereby producing different color hues.
In a laboratory under normal gravity conditions and with a closed oxygen valve, a Bunsen burner burns with yellow flame (also called a safety flame) at around 1,000 Ā°C (1,800 Ā°F). This is due to incandescence of very fine soot particles that are produced in the flame. With increasing oxygen supply, less black body-radiating soot is produced due to a more complete combustion and the reaction creates enough energy to excite and ionize gas molecules in the flame, leading to a blue appearance. The spectrum of a premixed (complete combustion) butane flame on the right shows that the blue color arises specifically due to emission of excited molecular radicals in the flame, which emit most of their light well below ~565 nanometers in the blue and green regions of the visible spectrum.
The colder part of a diffusion (incomplete combustion) flame will be red, transitioning to orange, yellow, and white as the temperature increases as evidenced by changes in the black-body radiation spectrum. For a given flameās region, the closer to white on this scale, the hotter that section of the flame is. The transitions are often apparent in fires, in which the color emitted closest to the fuel is white, with an orange section above it, and reddish flames the highest of all.[4] A blue-colored flame only emerges when the amount of soot decreases and the blue emissions from excited molecular radicals become dominant, though the blue can often be seen near the base of candles where airborne soot is less concentrated.
Specific colors can be imparted to the flame by introduction of excitable species with bright emission spectrum lines. In analytical chemistry, this effect is used in flame tests to determine presence of some metal ions. In pyrotechnics, the pyrotechnic colorants are used to produce brightly colored fireworks.
Flame temperature
A flame test for sodium. Note that the yellow color in this gas flame does not arise from the blackbody emission of soot particles (as the flame is clearly a blue premixed complete combustion flame) but instead comes from the spectral line emission of sodium atoms, specifically the very intense sodium D lines.
When looking at a flameās temperature there are many factors which can change or apply. An important one is that a flameās color does not necessarily determine a temperature comparison because black-body radiation is not the only thing that produces or determines the color seen; therefore it is only an estimation of temperature. Here are other factors that determine its temperature:
Adiabatic flame; i.e., no loss of heat to the atmosphere (may differ in certain parts).
Atmospheric pressure
Percentage oxygen content of the atmosphere.
The fuel being burned (i.e., depends on how quickly the process occurs; how violent the combustion is.)
Any oxidation of the fuel.
Temperature of atmosphere links to adiabatic flame temperature (i.e., heat will transfer to a cooler atmosphere more quickly).
How stoichiometric the combustion process is (a 1:1 stoichiometricity) assuming no dissociation will have the highest flame temperatureā¦ excess air/oxygen will lower it and likewise not enough air/oxygen.
In fires (particularly house fires), the cooler flames are often red and produce the most smoke. Here the red color compared to typical yellow color of the flames suggests that the temperature is lower. This is because there is a lack of oxygen in the room and therefore there is incomplete combustion and the flame temperature is low, often just 600ā850 Ā°C (1,112ā1,562 Ā°F). This means that a lot of carbon monoxide is formed (which is a flammable gas) which is when in fire and arson investigation there is greatest risk of backdraft. When this occurs combustible gasses, already at or above flash point of spontaneous combustion, are exposed to oxygen, carbon monoxide and superheated hydrocarbons combust and temporary temperatures of up to 2,000 Ā°C (3,632 Ā°F) occur.
Flame temperatures of common items include a candle at 1,400 Ā°C (2,600 Ā°F),[6] a blow torch ā at around 1,600 Ā°C (2,900 Ā°F) a propane torch at 1,995 Ā°C (3,620 Ā°F), or a much hotter oxyacetylene combustion at 3,000 Ā°C (5,400 Ā°F).
Common flame temperatures
This is a rough guide to flame temperatures for various common substances (in 20 Ā°C air at 1 atm. pressure):
Material burned Flame temperature (Ā°C)
Charcoal fire 750ā1,200
Methane (natural gas) 900ā1,500
Bunsen burner flame 900ā1,600 (depending on the air valve, open or close.)
Propane blowtorch 1,200ā1,700
Candle flame ~1,100 (majority), hot spots may be 1300ā1400
Backdraft flame peak 1,700ā1,950
Magnesium 1,900ā2,300
Hydrogen torch Up to ~2,000
MAPP gas 2,020
Acetylene blowlamp/blowtorch Up to ~2,300
Oxyacetylene Up to 3,300
Material burned Max. flame temperature (Ā°C, in air, diffusion flame)[4]
Animal fat 800ā900
Kerosene 990
Wood 1027
Gasoline 1026
Methanol 1200
Charcoal (forced draft) 1390
Hottest flame temperatures
Dicyanoacetylene, a compound of carbon and nitrogen with chemical formula C4N2 burns in oxygen with a bright blue-white flame at a temperature of 5260 K (4986.85 Ā°C, 9008.33 Ā°F), and at up to 6000 K in ozone. This high flame temperature is partially due to the absence of hydrogen in the fuel (dicyanoacetylene is not a hydrocarbon) thus there is no water among the combustion products.
Cyanogen, with the formula (CN)2, produces the second hottest known natural flame with a temperature of over 4525 Ā°C (or 8177 Ā°F) when it burns in oxygen.
Cool flames
At temperatures as low as 120 Ā°C, fuel-air mixtures can react chemically and produce very weak flames called cool flames. The phenomenon was discovered by Humphry Davy in 1817. The process depends on a fine balance of temperature and concentration of the reacting mixture, and if conditions are right it can initiate without any external ignition source. Cyclical variations in the balance of chemicals, particularly of intermediate products in the reaction, give oscillations in the flame, with a typical temperature variation of about 100 K, or between ācoolā and full ignition. Sometimes the variation can lead to explosion.
Flames in microgravity
In zero-G, convection does not carry the hot combustion products away from the fuel source, resulting in a spherical flame front.
In 2000, experiments by NASA confirmed that gravity plays an indirect role in flame formation and composition. The common distribution of a flame under normal gravity conditions depends on convection, as soot tends to rise to the top of a flame (such as in a candle in normal gravity conditions), making it yellow. In microgravity or zero gravity environment, such as in orbit, natural convection no longer occurs and the flame becomes spherical, with a tendency to become bluer and more efficient. There are several possible explanations for this difference, of which the most likely is the hypothesis that the temperature is sufficiently evenly distributed that soot is not formed and complete combustion occurs. Experiments by NASA reveal that diffusion flames in microgravity allow more soot to be completely oxidized after they are produced than do diffusion flames on Earth, because of a series of mechanisms that behave differently in microgravity when compared to normal gravity conditions. These discoveries have potential applications in applied science and industry, especially concerning fuel efficiency.
HOPE THIS INFORMATION WLL BE OF SOME HELP FOR ALL
Abner
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Last night I came across a slightly scary phenomenonā¦
Roughly an hour after doing some plasma cutting in my shop, I had to bend a piece of bar-stock with my handheld propane torch (the type that screws onto a Coleman camping bottle.) The entire flame was a deep red-orange color instead of the normal light-blue.
Because it had been almost an hour and several projects later, it took me a minute to realize that it was probably related to the plasma cutting and all the vaporized steel/iron in the air (or possibly ionized air from the plasma jet?).
I would hope that the very excellent article AbnerV put up would put an end here on the DOW to the silliness of using flare-staring as proof of success.
IF the purpose of woodgasification or charcoal gasification is internal combustion piston engine fueling, then only that engine will be the proper gas-quality judge. White paper towel test for tars. Then engine run with your produced gases mixes. IC piston engines will fuel just fine on non-ashed cored carbons/soots, too. It is the intake passages that eventually soots clog, requiring cleaning out.
And those āgasifingā for chemical input feed stocks for other processes need to be sending out their produced gasses to certified Labs, for analysis.
Engine guy Steve Unruh
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B U T if I canāt sustain a good flare there is no sense in wearing out a starter motor with gas that is not ready.
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I agreeā¦ see if it will ignite with a flint striker. ā¦ if it will. ā¦ run an engine on itā¦ personally, just flaring for the sake of flaring uses up good fuel stock
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Two years ago I cut my grass on only charcoal. First ever gasifire. Not a drop of gasoline. I still never flared the gas once or tried to light it. I could tell by the smell if it was ready. My wood gasifire for my truck all I have done is flair it because the truck is not finished. I pulled on it real hard two nights then tore it down for a look inside. I had a few leaks because it was not pressure tested. Sealed them all up pressure tested and put it back together. It is ready to refill and run but truck is only close.
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Donāt worry steve you wont ever see another flare from me
Theres alot of good ifo on this site and I have soaked it in as good as I can I donāt normally join chat groups of any kind because of the whiners. Some day I hope to learn as much about gassing as you think you have.
But am glad I wont be learning from you.
Mr. Wayne if I ever get to Alabama I would concider it a true prevlige to meet you.
Chris the same goes to you would also like to meet you
Thanks all
GOOD BYE
Jesse
1 Like
Hi, Don!
21.05.2016 15:00
You go with normal logic! You test.
Earlier (years back) even Steve accepted that steamy, wet or tarry gas was not to be offered to an innocent motor!
But effective filtering has (never) been his cup of tea.
Wet, steam-saturated gas is seen by the eye, aswell as bluish tarlayden gas.
Not before these obvious filthies are overcome by the process heat, is there ANY reason to do an IGNITION TEST!
By ignition test I mean NOT FORCE FLAME LIGHTING!
Any filthy gas can be forced to burn.
NO!
Test igniting happens with an EMPTY ! (oven-) gaslighter, giving just a small PIEZZO - spark.
THAT CORRESPONDS TO WHAT THE MOTOR HAS AT ITāS DISPOSAL!
In thousands of videos desperate flame - lighters are seen doing useless efforts to LIGHT filthy gasā¦
Abnerās article is good education!
Max
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Yes MaxG is very correct.
I wasted away a w-h-o-l-e year of my life believing the flare-starers that only a pure blue flare was indicative of acceptable motor fuel gas. A w-h-o-l-e year of my life participating in pink, purple, yellow flares as indicative of woodgas hydrogen, carbon monoxide and/or wood methane.
Since my goal was to make MY trees into electricity for use by us using piston internal combustion engines all of this gum-gnashing was wasted efforts.
Mike LaRosa and Doug Williams, and others kept encouraging to just tars check then engine run with it. They did.
Saw with my own eyes too many times output gas that would not flare would engine run.
And it was Mr Max Gasman who straitened me out that since my intent was to use my produced gas in spark internal engines to stop flame lighting flares. That ONLY a spark lit flare could ever be valid.
WE all learn and help each other. So learn from those who have done. Ignore those who internt-jabber and speculate for perfections and idealisms.
Regards
Steve Unruh
Hi, Steve!
22.05.2016 23:30
Thanks for the spark recognition!
Helping and advising nubies is not always straight forward, as the reception of a described methode can be taken as unjustified critic, or something otherwise undue or illadvismentā¦
I have had several disapointments in trying to describe methodes without achieving the hoped for resultā¦ Still restarting when ācalled forā, in oneās own opinion. Now and then facing an eye opener.
Max
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Thats nice Steve, glad you wastedu a years worth of work! !
Iāve been at this wood gas thing for maybe three mths and I had spark ignitable gas on my first try. (Just used a toch cause it was easier) as for the color of my flame it was perfect if you had actually read the information that Abner posted, you would know that blue is the color of total combustion, it also represents the hottest flame produced by black char radiation.
only reason Iām not making electricity is because I do not own
a small ICE. The first of August 2016 Iāll purchase an ICE. Then Iāll
build a real gasifier. Not just a front porch TOY meant for cooking.
By Nov. I will be making my own energy, and using the residual
heat to heat my Apt. And guess what Steve I wonāt have wasted a whole year.
The only thing holding me back is lack of funding.
What was your EXCUSE
Donāt complain about people asking questions. Its how we learn!
So have a COKE and a smile ā¦
Jesse
Hi Jesse
I think what you are doing is fine, at leased you are doing something.
To many people want to sit and talk, but not do anything. as long as your doing it will always grow into something bigger and better.
Thanks Jim
It just ticks me off a bit when I ask a question and get complaints or arrogance
Thought this was supposed to be the best wood gas forum
To tell the truth Iām ready for the rest and this WOODGAS CHAT GROUP CAN CAN GO ā¦ You know what I mean.
Iām not thin skinned by any means, but when I ask an innocent question about filtering with water and some A HOLE from accross the pond wants to go off on me about why would he want to do that when he just built a monorator hopper
Look at me Im slikker than wet shite! and your just some new guy. Or a question about flame color and have the GRUMPPY OLD MAN FROM WASHINGTON start bitchn about flare starers.
As I said before
IF THIS IS THE BEST
THEN IāM READY FOR THE REST
Jesse
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Steve and Max, Iām am a spark liter indeed. Also use my ears because I like to hear that nice open air puff. Use my eyes not so much for the flame but the clarity of the gas. Expect some white fog but for short duration. I need to find a āPIEZZO - sparkā, been using flint. My little saying is if it donāt lite with flint I donāt pull the rope. Iām the only one that never had luck starting an engine with gas that could not ignite.
Max, your gas chiller math worked good for meā¦ Thanksā¦!
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Lighten up Jesse. Theyāre trying to help.
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No need to get worked up Jesse.
What I hear when Steve talks about flare staring is, you have wood gas and hook it up to an engine. You have something good going on, now see what you can do with it. Many people spend their time trying to get what they think a good flare is. All that matters is if the engine likes it. An engine pulling on a gasifier under load is completely different than a vacuum from a fan.
I see it as Steve trying to help by saving you tons of time.
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Gee Jessie Really sucks you feel that way as read back through these posts I see nothing but very knowledgeable guys doing nothing but trying to help. If your not interested in constructive criticism or a little advice then it is probably best if you donāt post any thing for all to see. I have been part of this community for a few years now and have never seen anybody else ever feel anything but grateful for the help offered here or any other forum I have ever visited. If you are the only one that feels this way maybe it is you and best if you do bow out. really sorry you feel this way.
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Thanks, Jeff!
23.05.2016 11:50
You are hardly the only one experiencing that! Me for one.
I think āventilatingā with the motor by starter and accumulator is a waste of resources, aswell as serving dirt to the poor motor.
The variables in āfreshā start-up gas are āendlessā. The amount of hydrogen counter carbone dioxide and steam, among the most decisiveā¦
The āpoffā is a good hydrogen detector.
On the way to the motor, different filter media and dryness state affect how dry the gas will arriveā¦ In a tight system, the āyesterday gasā may also play a roleā¦
All observations are useful!
Max
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I think your comments about the filtering are in another thread
http://forum.driveonwood.com/t/what-kind-of-filter-media/2325/64
Pepe and Steve (both valuable and respected members of this FAMILY) along with everyone else have done nothing but try and help.
If you have a problem with the whole world it may not be the whole world at fault.
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