Simulation Study on the Interaction between Chemically Reacting Double Coal Char Particles.

Area of Science:

• Chemical Engineering
• Combustion Science
• Computational Fluid Dynamics

Background:

• Experimental determination of coal char reactivity is challenging under entrained flow gasifier conditions.
• Computational fluid dynamics (CFD) is crucial for simulating high-temperature coal char particle reactivity.

Purpose of the Study:

• Investigate the gasification characteristics of double coal char particles.
• Analyze the impact of particle distance and size on reactivity in H2O/O2/CO2 atmospheres.

Main Methods:

• Utilized computational fluid dynamics (CFD) simulations.
• Studied gasification of double coal char particles under varying H2O/O2/CO2 compositions.
• Varied inter-particle distance (L) and particle size (0.1–1 mm).

Main Results:

• Particle distance (L) affects reaction temperature and area migration, causing temperature to rise then fall as L increases.
• Increasing particle size from 0.1 to 1 mm enhances reaction rate and carbon consumption.
• For double particles, reaction rate trends are similar across sizes, but magnitude of change varies with distance; smaller particles show greater carbon consumption rate changes with distance.

Conclusions:

• Particle distance and size are significant factors influencing coal char gasification.
• CFD simulations provide valuable insights into complex gasification processes.
• Findings aid in optimizing gasifier performance and understanding char reactivity.