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Help with a kerosene lamp Answered

Hey guys, I recently got this silver lamp, which I've filled with kerosene. The only problem is every time I light it, it lets off a thick line of black smoke? I've tried trimming the wick down, but it hasn't helped.  Does anyone have any experience with this, or any suggestions?


First: yes: Use a different oil. If you do that and dont want to know why you can stop reading now.

Still here? Then you want to know about why it smokes and what exaclt should be the difference to the new oil.
OK then!
First i explain why a flame has color. Later you will see why it is important.
Many people dont think about it, but why does a flame has a color and why are there different colors with different flames? a clean naturalgas-flame is blue, candle and oil is normally yellow.
It is because of the composition of the gases and particles within the flame.
Immagine an iron rod: If you heat it enough, it will glow (emit light).
Now: If you sprinkle small particles of metallic salts (or even metals) into a clear flame, the flame gets colored. Thets because every element has a distinctive color. Copper gives a green colored flame as an example.
Now do the same with coal-dust (which is carbon): The color will be a red/yellow. Just as your candle or oillamp! Thats because the carbon glows in this color.
OK... Nice. But what has it to do with the black smoke?
in fact, thats very simple if you understood the stuff written above:
There is too much carbon in the flame.
Normally all the carbon reacts within the flame with the oxygen of the air and forms C02, Carbon dioxide. If not all carbon reacts, it leaves the flame as carbon (black smoke).
Now why doesnt the carbon not react completely in your lamp?
2 possible answers:
- Not enough oxygen supplyed to the flame.
- too much carbon in the gas

Lets first check on answer 2 if it leads us to a viable solution:
You cannot increase the oxygen-contents of the air. It is around 20%. So you cannot get "richer" air. But maybe more of the same Air? Since you dont have a design like a bunsen-burner where you can regulate the mixing-ratio of fuel (the gasified oil) and oxidizer (Oxygen from the air), this answer leads us nowhere.

So whats about the second answer? Well... Since you have a natural draft (The air-movement comes from beneth the flame and gets pulled up by the warm air-convection of the flame) your design is something like "the more flame the more heat and therefore the more convection and therefore the more air".
Normally the bigger the gas-volume (the bigger your flame) the bigger the heat. But unfortunately, it is not in scale. twice as big in the flame does not result in twice the heat and convection.
So you should try to trim down the whick (what you did) till a good air-gas-ratio is found and the black smoke ends. If thats not working (as by you) you should see if you can find a less rich oil.
Of you dilute the kerosene with an non-polar solvent like benzene (C6H6), carbon tetrachloride (CCl4), and diethyl ether ( CH3CH2OCH2CH3). But i think that would be a lot of hassle for that. Best if you find a less rich oil to burn. :)

Have fun with this really nice lamp! I like it! :)

Use differant lamp oil. Kero will always give off black smoke, but you need to shorten the wick after you get it lit to adjust it to where it stops smoking. At least thats the experance I've had with Kero-heaters.

Use a different lamp-oil, ask in the shop for advice.