Entropy Generation Analysis of a Thermal Cracking Reactor

Area of Science:

• Chemical Engineering
• Thermodynamics
• Reaction Engineering

Background:

• Understanding entropy generation is crucial for optimizing chemical reactors.
• Propane thermal cracking is an important industrial process with significant energy considerations.

Purpose of the Study:

• To analyze entropy generation in a tabular thermal cracking reactor using propane.
• To determine the molecular mechanism and quantify entropy sources (chemical reactions, heat transfer, pressure loss).
• To investigate the impact of feed and wall temperatures on entropy generation and reactor performance.

Main Methods:

• Development of a reaction model for propane cracking.
• Numerical solution of flow, reaction, momentum, and energy equations.
• Calculation of entropy generation rates from heat transfer, chemical reactions, and pressure loss.
• Parametric study varying feed and wall temperatures.

Main Results:

• Chemical reactions are the dominant source of entropy generation, followed by heat transfer and pressure loss.
• Lowering feed temperature increases heat transfer entropy initially; optimal wall temperature reduces overall entropy.
• Reduced wall temperature decreases product conversion, while feed temperature has minimal impact on product yield.
• Optimal wall temperature leads to the lowest entropy generation from chemical reactions.

Conclusions:

• Reactor performance and efficiency are significantly influenced by temperature parameters and their effect on entropy generation.
• Optimizing wall temperature is key to minimizing entropy and maximizing conversion in propane cracking reactors.
• The findings provide insights for designing and operating more efficient thermal cracking processes.