To achieve high combustion efficiency and stable fuel feeding,
this biomass was burned as shredded fuel with individual
particles of up to 9 mm in sieve size. The shape and size of the
shredded shell were quite irregular: from sawdust-like fine
particles to flake-shape coarse particles. Fig. 1 depicts the particle
size distribution (as wt.% for selected size groups) of oil palm oil
kernel shell used in this study. It can be concluded from this
analysis that the biomass was basically represented by particles of
0.5–9.0 mm in sieve size. However, shell particles of 3–6 mm in
sieve size were apparently predominant in the biomass sample.
The standard analysis of fuel ash (wt.%, as oxides) exhibited the
predominant proportion of silicon (SiO2 = 54.12%), followed by
calcium (CaO = 23.21%), potassium (K2O = 8.12%), and iron
(Fe2O3 = 6.14%). The elevated potassium content in the fuel ash
indicated a potential problem (bed agglomeration) during the
combustion of this biomass in a fluidized bed with conventional