Biomass residues have potential to be used as an
alternative solid fuel for various processes, also will be responsible
for the optimization of the pyrolysis reaction processes, giving
insight into the pyrolysis mechanisms and aiding in engineering
efforts. There are different methods for production of bio-fuel
from biomass residues; however before the production of bio-fuels
from biomass it is important to understand their thermal
degradation and kinetics. In the present work the Kinetics studies
of four different walnut shells, namely, paper (PSW), thin (TSW),
medium (MSW) and hard (HSW) shelled walnuts have been
studied. Thermal degradation behaviour of walnut shells is
investigated using thermogravimetric analysis (TGA) under three
different heating rates (30, 60 and 100 0Cmin−1
) in an oxidizing
atmosphere to understand the kinetic behavior.
Kissinger–Akahira–Sunose (KAS) and Ozawa–Flynn–Wall
(OFW) methods were used to estimate the kinetic parameters such
as Pre-exponential factor (R) and average activation energy (Ea
)
using TGA data of active zone. The average activation energy of
biomass obtained from PSW, TSW, MSW and HSW using KAS
method were 198.25, 184.21, 180.93, and 152.79 kJ mol−1
,
respectively. Whereas by OFW method the values were found to be
204.10, 186.28, 188.39 and 153.78 kJ mol−1
respectively. Thus the
present investigation may be useful for its use as a renewable
energy source and potential candidate for fuel production by
thermo-chemical processes.