Preparation of Fuels for Combustion

Gaseous fuels do not need to be broken up into particles because gas, by its very nature, is able to mix with air in its native form.

Heavy fuel oils need to be atomized (broken into small particles) before they can be burned in a furnace. Atomization allows fuel to come in intimate contact with atmospheric air, which increases the combustion efficiency.

Atomization is usually achieved by mixing fuel oil with either steam or compressed air, and then releasing the mixture through a spray nozzle into the furnace. The spray nozzle breaks oil into small particles.

Viscosity also plays a key role in the ability of oil to atomize. Heavier oils, at room temperature, do not atomize well. To improve atomization, heavier oils are preheated and then introduced into an atomizing gun (commonly referred to as the “oil gun”). No. 6 oil is usually heated to about 200 deg F before it is introduced into an oil gun.