4. Conclusion
The adverse impact of highly toxic generated oily wastewaters
as well as scarcity of water resources in many regions
around the world has driven many researchers and scientists
toward developing useful techniques and approaches to
produce treated waters of a quality suitable for reuse and
recycling. That being stated, technologies such as electrochemical,
membrane-based, adsorption and many others
have been investigated at different design parameters and
operating limitations. Promising results were reported, yet
continuous improvements and innovative solutions along
with the cooperative efforts from local and international
governments need to be put together toward on-the-ground
implementation. In general, there is increasing need to devise
new sustainable approaches for oily wastewater treatment
that will be geared toward economic savings and environmental
preservation, as most of the previous methods are
either too costly to be implemented on a commercial scale or
require large environmental footprints. Acids had been used,
some decades ago, to break down the oil molecules from
water. However, because of the labor-intense nature of acid
treatment, many of the recent treatment methods discussed
in this paper have been developed to make the treatment of
oily wastewater become easier and more efficient. Furthermore,
more attention should be focused on extremely toxic
contaminants that may be present in oily wastewater such as
radionuclides, persistent organic pollutants, and PHCs. The
release of these substances to soil, water, or air would pose
serious threats to the existence of life and environmental
sustainability. A single technology cannot satisfy all of the
reuse and disposal requirements for different oily sludge
wastes. The use of microbial decomposition to remove
pollutants from oily wastewater also has its drawbacks, as