Palm Kernel Shells Biomass residue from palm oil industries are
attractive renewable energy fuel in Southeast Asia. The abundance
of these biomass resources is increasing with the fast development
of palm oil industries in Malaysia, Indonesia and Thailand. In the
Palm Oil value chain there is an overall surplus of by-products and
the utilization rate of these by-products is
low. Palm kernel shells (or PKS) are the shell
fractions left after the nut has been removed after crushing in the
Palm Oil mill. Kernel shells are a fibrous material and can be
easily handled in bulk directly from the product line to the end
use. Large and small shell fractions are mixed with dust-like
fractions and small fibres. Moisture content in kernel shells is low
compared to other biomass residues with different sources
suggesting values between *1% and *3%. Palm kernel shells contain
residues of Palm Oil, which accounts for its slightly higher
heating value than average lignocellulosic biomass. Compared to
other residues from the industry, it is a good quality biomass fuel
with uniform size distribution, easy handling, easy crushing, and
limited biological activity due to low moisture
content Press fibre and shell generated by the palm oil
mills are traditionally used as solid fuels for steam boilers. The
steam generated is used to run turbines for electricity production.
These two solid fuels alone are able to generate more than enough
energy to meet the energy demands of a palm oil mill. Most palm oil
mills in the region are self-sufficient in terms of energy by
making use of kernel shells and mesocarp fibers in
cogeneration. The demand for palm kernel shells has increased
considerably in Malaysia, Indonesia and Thailand resulting in price
close to that of coal. Nowadays, cement industries are using palm
kernel shells to replace coal mainly because of CDM
benefits. The problems associated with the burning of
these solid fuels are the emissions of dark smoke and the
carry-over of partially carbonized fibrous particulates due to
incomplete combustion of the fuels can be tackled by
commercially-proven technologies in the form of high-pressure
boilers. Dual-fired boilers capable of burning either diesel oil or
natural gas are the most suitable for burning palm Oil waste since
they could also facilitate the use of POME-derived biogas as a
supplementary fuel. However, there is a great scope for
introduction of high-efficiency CHP systems in the industry which
will result in substantial supply of excess power to the public
grid.
