Carbon dioxide dilution effect on flammability limits for hydrocarbons

Area of Science:

• Chemical Engineering
• Combustion Science
• Thermodynamics

Background:

• Flammability limits are critical safety parameters for hydrocarbon-inert gas mixtures.
• Predicting these limits accurately is essential for safe industrial operations.
• Existing models may lack precision or broad applicability.

Purpose of the Study:

• To develop and validate theoretical models for predicting upper and lower flammability limits.
• To investigate the relationship between flammability limits and hydrocarbon concentration.
• To assess the applicability of these models across various hydrocarbon types.

Main Methods:

• Development of theoretical models based on chemical principles.
• Analysis of linear relationships between reciprocal flammability limits and reciprocal hydrocarbon mole fractions.
• Validation using existing experimental data for methane, propane, ethylene, and propylene.

Main Results:

• Established theoretical linear relationships for upper and lower flammability limits.
• Experimental data confirmed these linear relationships with high coefficients of determination (R² > 0.959).
• Models demonstrated strong agreement with experimental results for multiple hydrocarbons.

Conclusions:

• The proposed theoretical models accurately predict flammability limits in hydrocarbon/CO2 mixtures.
• The models show potential for extension to other flammable materials and inert gases.
• The theoretical model for lower flammability limit aligns with existing empirical models.