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How much air does it take to burn propane?

How much air does it take to burn propane?

If a mixture of gas and air contains less gas than is needed for ideal combustion, then it is referred to as a lean burn. The ideal combustion ration (“complete combustion”) for propane is 1 part propane (4%) to 24 parts of air (96%). Even at this ideal ration, combustion products, known as flue gases, still occur.

Why do we need more air for combustion for propane?

When not enough oxygen is present for complete combustion, incomplete combustion occurs when propane burns and forms water, carbon monoxide, carbon dioxide,and carbon. Unlike natural gas, propane is heavier than air (1.5 times as dense). These bonds also cause propane toburn with a visible flame.

How do you calculate air needed for combustion?

Therefore the quantity of oxygen required for combustion of 1 kg of the fuel is: (2.66C + 8H + S) kg. ∴ Oxygen required from air for the complete combustion of fuel will be (2.66C + 8H + S – O) which can be written as 2.66C + 8 (H – O/8) + S, the term in the bracket being known as the available hydrogen.

How much air is required for perfect combustion?

As a “rule of thumb,” 1 ft3 of natural gas theoretically requires 10 ft3 of air for complete combustion at 60°F and 14.7 psi under perfect conditions.

How much propane is needed to make propane combustible?

This means that between 2.15 and 9.6% of the total propane/air mixture must be propane in order for it to be combustible. If the mixture is 2% propane and 98% air, there will not be combustion. If the mixture 10% propane and 90% air, combustion will not occur.

How can incomplete combustion occur in a propane burner?

Incomplete propane combustion can occur in one of two ways: Propane Lean Burn- The ratio of propane to air is less than 4 parts propane. 2.5 parts propane to 97.5 parts air would produce a lean burn. A lean burn can be recognized when flames appear to lift away from the burner and can potentially go out.

How much air does a natural gas burner need?

For natural gas fired burners,  the stoichiometric air required is 9.4-11 ft.3 / 1.0 ft.3 of natural gas, or approximately an air-to-gas ratio of approximately 10:1. This results in an excess oxygen level of 2%. In the combustion zone, it is difficult to measure excess air.

What should the outside temperature be for propane to burn?

In other words, if the outside air temperature is -155°F, propane will burn on it’s own. If the outside air temperature falls to -157°F, propane will no longer burn on it’s own. However, if a source of continuous ignition is present, propane will burn below – 156°F.