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Reducing Smoke in Pyrotechnic Mixtures


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#1 darkfang77

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Posted 08 September 2010 - 09:01 PM

Hello,
I have been doing a few mixtures lately and the smoke given off from the mixtures are blocking the effect! Especially when the wind is in the wrong direction.
Has anyone here had similar problems? And how do you remedy these problems?
Moreover, are there any particular mixtures that make a lot of smoke? And how does one reduce smoke?

As far as I know, mixtures containing magnesium, and potassium nitrate will emit lots of smoke.
What is the smoke composed of? Metallic oxides?

What chemicals emit lots of smoke?

#2 dr thrust

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Posted 08 September 2010 - 10:40 PM

oxides, carbon dioxide,water,unburnt comp.
bp when it burns One study showed it produced: 55.91% solid products-- Potassium carbonate, Potassium sulfate, Potassium sulfide, Sulfur, Potassium nitrate, Potassium thiocyanate, Carbon, Ammonium carbonate--and 42.98% gaseous products--Carbon dioxide, Nitrogen, Carbon monoxide, Hydrogen sulfide, Hydrogen, Methane, Water (pyro guide).
i think you need a oxidizer with a higher oxygen content for a more complete combustion hence less smoke.
edit reminds me of when i tried manganese oxide rockets, you dont want to breath that in," metal fume poisoning anybody?".
i guess its relative to what pyro your using, low level ground effects in a walled yard ect the smoke has nowhere to go, where as shells, rockets can dissipate it over a larger area

Edited by chris m, 08 September 2010 - 10:46 PM.


#3 darkfang77

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Posted 09 September 2010 - 08:03 AM

oxides, carbon dioxide,water,unburnt comp.
bp when it burns One study showed it produced: 55.91% solid products-- Potassium carbonate, Potassium sulfate, Potassium sulfide, Sulfur, Potassium nitrate, Potassium thiocyanate, Carbon, Ammonium carbonate--and 42.98% gaseous products--Carbon dioxide, Nitrogen, Carbon monoxide, Hydrogen sulfide, Hydrogen, Methane, Water (pyro guide).
i think you need a oxidizer with a higher oxygen content for a more complete combustion hence less smoke.
edit reminds me of when i tried manganese oxide rockets, you dont want to breath that in," metal fume poisoning anybody?".
i guess its relative to what pyro your using, low level ground effects in a walled yard ect the smoke has nowhere to go, where as shells, rockets can dissipate it over a larger area


It's not specific to the circumstances, the smoke is sort of "heavy", it convects its way down and stays there for a minute for disappating. That's the annoying part, when it falls down, it stays down like a fog, and 30 secs later its mysterious gone. That's what ruining some of the effects. The fog just doesn't look nice.
More oxidiser will sort this out you say? I will try that out.

#4 pyrotrev

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Posted 09 September 2010 - 12:47 PM

It's not specific to the circumstances, the smoke is sort of "heavy", it convects its way down and stays there for a minute for disappating. That's the annoying part, when it falls down, it stays down like a fog, and 30 secs later its mysterious gone. That's what ruining some of the effects. The fog just doesn't look nice.
More oxidiser will sort this out you say? I will try that out.


Sounds like it might simply be atmospheric humidity - often a problem in the UK. microscopic particles of combustion products which would only produce a thin smoke act as centres for moisture to condense on, forming a thick fog. Note also that compositions containing metal powders tend to make a lot more smoke that those with purely organic fuels.
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#5 darkfang77

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Posted 09 September 2010 - 02:30 PM

Sounds like it might simply be atmospheric humidity - often a problem in the UK. microscopic particles of combustion products which would only produce a thin smoke act as centres for moisture to condense on, forming a thick fog. Note also that compositions containing metal powders tend to make a lot more smoke that those with purely organic fuels.


Ahh, so you're saying I should try this out on a Sunny day? Or a very hot/dry/cold night??

#6 dr thrust

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Posted 09 September 2010 - 03:43 PM

More oxidizer will sort this out you say? I will try that out.

i was thinking more like potassium perchlorate (kcl04) with the extra oxygen atom as apposed to potassium nitrate (kno3) with only 3 oxygen atoms

#7 a_bab

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Posted 09 September 2010 - 03:54 PM

Smoke is generally a problem with pyro. I even personally witnessed a pyro show that was paused midway till the smoke dissipated a bit, with the required excuses from the displayer. The effects were barely visible behind the smoke which just lingered in the sky. It was a cold, very humid night, with no wind at all.

I'm afraid we can't get rid of the smoke, but there are studies to solve the issue. The answer is either exotic expensive chems, involving those found in the (most) recent aibags, or simply NC based stars.

For an amateur, making (visible) less smoke in a certain star formulation is going to be impossible. Your problem is the weather as it's been said.

Edited by a_bab, 09 September 2010 - 07:34 PM.


#8 dr thrust

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Posted 09 September 2010 - 04:41 PM

i remember seeing two waterfalls made by phil d, one perc based, one nitrate lets just say the nitrate waterfall was very smokey :P.
perc recovered from airbags? how much?,down to the scrap yard for a capri gearbox and some perc?

Edited by chris m, 09 September 2010 - 04:52 PM.


#9 darkfang77

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Posted 09 September 2010 - 05:35 PM

I remember a while back, when I just had my first batch of pyro chems, I mixed approx 6-7 grams of KNO3 to 8 grams of sugar, There was loads of smoke, but thank fully the wind that day was ginormous, blew all the smoke over the brick wall and away. On a bad windless day, the smoke will linger, and make it look as if the house is on fire.

Very bad...

So no solutions other than using perchlorate?

#10 a_bab

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Posted 09 September 2010 - 05:47 PM

The airbags have sodium azide and not perc.

I was thinking about the new airbags based on tetrazoles.

#11 Arthur Brown

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Posted 09 September 2010 - 06:26 PM

"Smokeless" usually means fully organic with lots of nitrocellulose with all the regulatory hassle of a HE of specified nitrogen content.

The Sodium, potassium, strontium etc metal salts WILL cause metal oxides in the burn product which is usually the ash and smoke.
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#12 darkfang77

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Posted 09 September 2010 - 06:32 PM

"Smokeless" usually means fully organic with lots of nitrocellulose with all the regulatory hassle of a HE of specified nitrogen content.

The Sodium, potassium, strontium etc metal salts WILL cause metal oxides in the burn product which is usually the ash and smoke.


I do realise this problem, but whilst I can live with it. I want to see if there are any ways to reduce smoke. Not make it totally smokeless.

#13 dr thrust

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Posted 09 September 2010 - 10:11 PM

rounding this up in a nut shell, use an organic fuel with an oxygen rich oxidizer, try it for yourself say compare a organic white star against a metal fuel star on smoke production and post your results

#14 darkfang77

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Posted 10 September 2010 - 12:30 AM

rounding this up in a nut shell, use an organic fuel with an oxygen rich oxidizer, try it for yourself say compare a organic white star against a metal fuel star on smoke production and post your results


Will do. I'll see what I can get.




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