# Efficient Method of Producing Heat Using LPG

by PraAnan
Tags: efficient, heat, method, producing
 P: 34 I'm trying to heat a 55mm x 55mm piece of aluminium to a minimum temperature of 250 Celsius (max is 300C) using LPG at a rate of 300Btu/hr. The issue I'm having is that because I'm using a flame the temperature across the entire surface isn't uniform. I've read about catalytic flame-less combustion of gases and after doing a little bit of research I came across the following products. Infrared Honeycomb and Catalytic Heaters First of all, are the materials being sold in the first link the same as the ones that are in the heaters in the second link? Is it more efficient to convert LPG to heat using a catalytic method rather than a flame based one? What is the starting procedure for these ceramic based materials? Is it as simple as starting the gas flow and then adding a spark or is it more complicated? Lastly, I'm curious to know about how long these ceramics can be used for before they start loosing efficiency and/or start breaking down from the heat.
 PF Patron Sci Advisor P: 1,767 As long as you are getting complete combustion, all methods are equally efficient in terms of conversion of energy. All mentioned methods can be max efficient... or less so if the design of equipment isn't optimal. Test for CO emissions and soot formation which indicate incomplete combustion.
 P: 34 I don't have access to any CO or soot measuring equipment but would a simple way to measure soot be to just keep a piece of metal on the flame and see if there is any build up? Because to calculate the rate of lpg use I'm actually using a gas cooker and I've never noticed any build-up or residue on the surface of anything that I used. Also, the flames on the stove are blue in colour, doesn't a blue flame usually indicate that it is clean burning and therefore showing that the efficiency is high?
PF Patron
P: 1,767

## Efficient Method of Producing Heat Using LPG

 Quote by PraAnan I don't have access to any CO or soot measuring equipment but would a simple way to measure soot be to just keep a piece of metal on the flame and see if there is any build up? Because to calculate the rate of lpg use I'm actually using a gas cooker and I've never noticed any build-up or residue on the surface of anything that I used. Also, the flames on the stove are blue in colour, doesn't a blue flame usually indicate that it is clean burning and therefore showing that the efficiency is high?
Testing with the piece of metal may cause soot by causing incomplete combustion. If you see soot building up in your setup then that indicates you should adjust flame. I don't think you need to worry much about inefficienty w.r.t. complete combustion. One of the main concerns is safety. Catalytic burners can reduce CO danger when using LPG without a vent but one should still be cautious. The blue flame doesn't necessarily mean complete carbon combustion from a safety standpoint. The blue color is the hydrogen burning in the hydrocarbon LPG. You will notice a difference between pure hydrogen flame, methane, propane, and butane. Each having higher carbon ratio has a higher yellow component to the flame up to the paraffin of a candle which has little noticable blue.

But I am getting way off topic. It sounds like with your setup, combustion efficiency is close enough to 100% to not be an issue. You lose more heat via radiation and convection than you might be losing to incomplete burning.