Overall characterization of cork dust explosion

Area of Science:

• Combustion Science and Engineering
• Materials Science
• Chemical Engineering

Background:

• Cork dust, a byproduct of cork processing, presents potential explosion hazards.
• Understanding the explosibility and ignitability of cork dust is crucial for industrial safety.
• Previous research has not fully characterized the complex interplay of factors influencing cork dust explosions.

Purpose of the Study:

• To comprehensively evaluate the explosibility and ignitability characteristics of air/cork dust mixtures.
• To determine the influence of particle size, dust concentration, initial pressure, and ignition energy on explosion parameters.
• To assess the impact of methane co-combustion on cork dust explosion behavior.

Main Methods:

• Experiments were conducted in a 22.7 L explosibility test chamber and a 1.23 L furnace.
• Dust cloud uniformity was verified using optical dust probes.
• Key parameters measured include minimum explosible concentration (MEC), maximum explosion pressure (Pmax), maximum rate of pressure rise (dP/dt)max, and minimum autoignition temperature (MAIT).

Main Results:

• MEC was approximately 40 g/m³, largely independent of particle size below 180 µm.
• Pmax reached 7.2 bar and (dP/dt)max reached 179 bar/s for the smallest particles.
• Increased initial pressure, higher dust loading, and larger particle sizes intensified explosions, while 2500 J ignition energy proved optimal for MEC determination. Hybrid methane-cork dust explosions showed increased hazard with higher methane concentrations.

Conclusions:

• Cork dust explosions are significantly influenced by particle size, concentration, initial pressure, and ignition energy.
• The presence of methane exacerbates the explosion hazard of cork dust.
• MAIT was determined to be 540°C, independent of particle size below 80 µm.