(Jameson) cell was more effective to remove oil from the wastewater with an
efficiency of 85%. To validate these findings, a test was also conducted on a
maritime platform. Again, the modified jet (Jameson) cell achieved a high oil
removal rate of 81%.
Besides that, the treatment methods using a combination of the physical and
biological processes were also investigated. Peng et al. (2014) introduced a
biological-physicochemical pretreatment of the oily wastewater prior to the anaerobic digestion process. The authors found that the digestibility of the oily wastewater
was improved after the introduction of oil degradationbacteria, Bascillus sp. A study
conducted by Rattanapan et al. (2011) has suggested the high efficiency of the
combination of dissolved air flotation, acidification, and coagulation in treating
biodiesel wastewater. Their findings demonstrated that the dissolved air flotation
alone and dissolved air flotation with acidification were not effective enough to give
high rejection performance. Meanwhile, the combination of dissolved air flotation,
acidification, and coagulation was found to successfully remove 85–95% of biodiesel in wastewater. In addition, Siles et al. (2011) confirmed that the combination of
electrocoagulation, acidification, and biomethanization was very efficient for the oily
wastewater treatment as it removed up to 99% of the chemical oxygen demand.
Meanwhile, a relatively low chemical oxygen demand removal of 94% was achieved
when a combination system of acidification, coagulation, flocculation, and
biomethanization was applied. The previous works on hybrid technologies to eradicate the contaminants from various sources of oily wastewater are tabulated in
Table 11.6.
The combination of different membrane technologies for oily wastewater treatment was studied by Salahi et al. (2012). The research team applied the combined
system of ultrafiltration and reverse osmosis and achieved excellent removal efficiencies for oil and grease (100%), total organic carbon (98%), chemical oxygen
demand (98%), total dissolved solids (95%) and turbidity (100%). Ong et al. (2014)
studied the oil removal performance of the submerged photocatalytic membrane
reactors in which the titania-embedded polyvinylidene fluoride membranes were
exposed under the ultraviolet light. A high degradation performance was achieved
with 80% and > 90% of the total organic carbon and oil removal efficiencies.
In addition, various attempts have been reported on the combination of adsorption
and filtration for the oily wastewater treatment. For instance, Abdullah et al. (2010)
applied this approach using a kapok fiber as the filtering material to eradicate the oil
and grease content in the diesel oil, as well as new and used engine oils. Their results
demonstrated that 1 gram of kapok filter could remove up to 36.7 g, 47.4 g and
50.8 g of diesel, new engine oil and used engine oil, respectively. Interestingly, the
kapok filter remained stable even after 15 cycles of test. Zhao and his team (2011)
developed a sponge-like exfoliated vermiculite and carbon nanotube hybrids and
found that the intercalation of carbon nanotube arrays improved the oiladsorption
capacities. The results also showed that the oiladsorption capacity was increased
from 26.7 to 70.6 g/g when the sponge-like exfoliated vermiculite and carbon
nanotube hybrid was transformed into fluffy exfoliated vermiculite and carbon
nanotube cotton using a high-speed shearing. Meanwhile, activated carbon has
374
M. H. D. Othman et al.
efficiency of 85%. To validate these findings, a test was also conducted on a
maritime platform. Again, the modified jet (Jameson) cell achieved a high oil
removal rate of 81%.
Besides that, the treatment methods using a combination of the physical and
biological processes were also investigated. Peng et al. (2014) introduced a
biological-physicochemical pretreatment of the oily wastewater prior to the anaerobic digestion process. The authors found that the digestibility of the oily wastewater
was improved after the introduction of oil degradationbacteria, Bascillus sp. A study
conducted by Rattanapan et al. (2011) has suggested the high efficiency of the
combination of dissolved air flotation, acidification, and coagulation in treating
biodiesel wastewater. Their findings demonstrated that the dissolved air flotation
alone and dissolved air flotation with acidification were not effective enough to give
high rejection performance. Meanwhile, the combination of dissolved air flotation,
acidification, and coagulation was found to successfully remove 85–95% of biodiesel in wastewater. In addition, Siles et al. (2011) confirmed that the combination of
electrocoagulation, acidification, and biomethanization was very efficient for the oily
wastewater treatment as it removed up to 99% of the chemical oxygen demand.
Meanwhile, a relatively low chemical oxygen demand removal of 94% was achieved
when a combination system of acidification, coagulation, flocculation, and
biomethanization was applied. The previous works on hybrid technologies to eradicate the contaminants from various sources of oily wastewater are tabulated in
Table 11.6.
The combination of different membrane technologies for oily wastewater treatment was studied by Salahi et al. (2012). The research team applied the combined
system of ultrafiltration and reverse osmosis and achieved excellent removal efficiencies for oil and grease (100%), total organic carbon (98%), chemical oxygen
demand (98%), total dissolved solids (95%) and turbidity (100%). Ong et al. (2014)
studied the oil removal performance of the submerged photocatalytic membrane
reactors in which the titania-embedded polyvinylidene fluoride membranes were
exposed under the ultraviolet light. A high degradation performance was achieved
with 80% and > 90% of the total organic carbon and oil removal efficiencies.
In addition, various attempts have been reported on the combination of adsorption
and filtration for the oily wastewater treatment. For instance, Abdullah et al. (2010)
applied this approach using a kapok fiber as the filtering material to eradicate the oil
and grease content in the diesel oil, as well as new and used engine oils. Their results
demonstrated that 1 gram of kapok filter could remove up to 36.7 g, 47.4 g and
50.8 g of diesel, new engine oil and used engine oil, respectively. Interestingly, the
kapok filter remained stable even after 15 cycles of test. Zhao and his team (2011)
developed a sponge-like exfoliated vermiculite and carbon nanotube hybrids and
found that the intercalation of carbon nanotube arrays improved the oiladsorption
capacities. The results also showed that the oiladsorption capacity was increased
from 26.7 to 70.6 g/g when the sponge-like exfoliated vermiculite and carbon
nanotube hybrid was transformed into fluffy exfoliated vermiculite and carbon
nanotube cotton using a high-speed shearing. Meanwhile, activated carbon has
374
M. H. D. Othman et al.