Palm Oil processing gives rise to highly
polluting waste-water, known as Palm Oil Mill Effluent (POME), which is
often discarded in disposal ponds, resulting in the leaching of
contaminants that pollute the groundwater and soil, and in the release
of methane gas into the atmosphere. POME is an oily wastewater generated
by palm oil processing mills and consists of various suspended
components. This liquid waste combined with the wastes from steriliser
condensate and cooling water is called palm oil mill effluent (POME). On
average, for each ton of FFB (fresh fruit bunches) processed, a
standard palm oil mill generate about 1 tonne of liquid waste with
biochemical oxygen demand (BOD) 27 kg, chemical oxygen demand (COD) 62
kg, suspended solids (SS) 35 kg and oil and grease 6 kg
POME has a very high Biochemical Oxygen
Demand (BOD) and Chemical Oxygen Demand (COD), which is 100 times more
than the municipal sewage. POME is a non-toxic waste, as no chemical is
added during the oil extraction process, but will pose environmental
issues due to large oxygen depleting capability in aquatic system due to
organic and nutrient contents. The high organic matter is due to the
presence of different sugars such as arabinose, xylose, glucose,
galactose and manose. The suspended solids in the POME are mainly
oil-bearing cellulosic materials from the fruits. Since the POME is
non-toxic as no chemical is added in the oil extraction process, it is a
good source of nutrients for microorganisms.
Currently, recovery of renewable
organic-based product is a new approach in managing POME. The technology
is aimed to recover by-products such as volatile fatty acid, biogas and
poly-hydroxyalkanoates to promote sustainability of the palm oil
industry. In addition, it is envisaged that POME can be sustainably
reused as a fermentation substrate in production of various metabolites
through biotechnological advances. In addition, POME consists of high
organic acids and is suitable to be used as a carbon source
Anaerobic digestion is widely adopted in
the industry as a primary treatment for POME. Biogas is produced in the
process in the amount of 20 m3 per ton FFB. This effluent
could be used for biogas production through anaerobic digestion. At many
Palm-oil mills this process is already in place to meet water quality
standards for industrial effluent. The gas, however, is flared
off. Liquid effluents from Palm Oil mills in Southeast Asia can be used
to generate power through gas turbines or gas-fired engines.
