Slow pyrolysis of indigenous Makarwal coal: characterization, kinetic study, and calculation of design parameters

ABSTRACT

Pyrolysis is a common stage of many coal utilization processes such as carbonization, gasification, combustion, and liquefaction. Char is the main product from slow pyrolysis of coal. Proximate analysis of Makarwal coal sample has ash contents of 34.61% and heating rate of 12,300 Btu/lb. CHNS analysis yields the elemental carbon of 43.41 % and sulfur amount of 58.041% which can be removed by further treatment process. Thermo-gravimetric analysis (TGA) study of Makarwal coal sample recognized that maximum decomposition takes place at 441ºC. The rate of reaction, rate constant and activation energy estimated from the kinetic study of slow pyrolysis are 7.55*10⁻⁵ mol/cm^3.s, 0.001135/s and 0.045 kj/mol, respectively. Experiments were performed at different coal particles with size ranging from 0.5 to 0.2 mm and heating rate of 9–15ºC/min at temperature range of 300–700ºC under inert N₂ gas atmosphere. Char is the main product in this study which is maximum at 9ºC/min and temperature of 300ºC having conversion rate of 92%. The desired char products have 44.63% fixed carbon and HHV of 14,300 Btu/lb.

KEYWORDS:

• Pyrolysis
• Makarwal coal
• fixed bed reactor
• TGA
• reactor kinetics
• effect of
• operating parameters

Additional information

Notes on contributors

Hafiz Miqdad Masood

Hafiz Miqdad Masood is a student of Master of Chemical Engineering at UET, Lahore and working as Assistant Lecturer in Chemical Engineering.

Najaf Ali

Najaf Ali is Assistant Professor in the subject of Chemical Engineering and is Ph.D in chemical engineering.

Tanveer Iqbal

Tanveer Iqbal is Associate Professor in Chemical Engineering at UET, KSK and Ph.D Chemical Engineering.

Muhammad Zafar

Muhammad Zafar is Professor of Chemical Engineering at UET, Lahore.