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Pure Component Gas Mixture (Le Chatelier) Combustion Products

Look up flammability limits and calculate stoichiometric air for a single component

Pure Component

Select Gas

Gas Mixture Composition

Enter mol% for each component. Must total 100%.

Methane (CH₄)

mol%

Ethane (C₂H₆)

mol%

Propane (C₃H₈)

mol%

n-Butane (C₄H₁₀)

mol%

CO₂

mol%

N₂

mol%

H₂S

mol%

Total: 100.0%

Combustion Conditions

Excess Air

Typical: 10-20% for burners, 50-100% for flares

Fuel Gas Flow Rate

Ambient Temperature

°F

Operating Conditions

Temperature

°F

LEL/UEL vary with temperature

Pressure

psia

Standard: 14.696 psia. UEL increases at elevated pressure.

Learn the Theory

Flammability limits, Le Chatelier's rule, combustion chemistry, and flame propagation

Read Engineering Guide

Engineering Basis

Le Chatelier's Mixing Rule

1/LEL_mix = Σ(y_i / LEL_i)

Calculates flammability limits for gas mixtures from pure component limits weighted by mole fractions.

Stoichiometric Combustion

CₙHₘ + (n + m/4)O₂ → nCO₂ + (m/2)H₂O

Complete combustion requires exact oxygen ratio. Excess air ensures complete burn.

NFPA 68/69 API 521 GPSA Ch. 1

Common Flammability Limits

Methane5.0 – 15.0%

Ethane3.0 – 12.4%

Propane2.1 – 9.5%

Hydrogen4.0 – 75.0%

H₂S4.0 – 44.0%

Combustion & Flammability Calculator

Pure Component

Gas Mixture Composition

Combustion Conditions

Operating Conditions

Learn the Theory

Engineering Basis

Results

Common Flammability Limits

Combustion & Flammability Calculator

Pure Component

Gas Mixture Composition

Combustion Conditions

Operating Conditions

Learn the Theory

Engineering Basis

Results

Common Flammability Limits

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