**Table 1.**

*Comparison of the separation techniques.*

cost needed is high and skillful personnel to be in charge is required to ensure the treatment functioned well.

use different separation techniques. **Table 2** shows examples of companies that

Different techniques are available and being used in the oil–water separation techniques for bilge water treatment. Typically, more than one unit of separators is needed to meet the minimum allowable discharge limit value set by the regulatory bodies. Gravitational and centrifugal methods are said to be the first technique before undergoing further polishing separation. Polishing treatment unit caters smaller droplet of oil, or emulsified oil, which cannot be treated by gravitational and centrifugal methods. To conclude, oily bilge water can be treated with proper separation techniques so that the treated bilge water discharged to the sea comply with the limit and marine pollution can be minimized and prevented. Any other treatment techniques can as well be tested and introduced to enhance the oil–water

The authors would like to acknowledge the Centre for Biofuel and Biochemical Research (CBBR) and Chemical Engineering Department, Universiti Teknologi

produced commercially available bilge water separators.

*Oil–Water Separation Techniques for Bilge Water Treatment*

*DOI: http://dx.doi.org/10.5772/intechopen.91409*

separation process in treating bilge water.

The authors declare no conflict of interest.

Nurul Aini Amran1,2\* and Siti Nor Adibah Mustapha1,2

\*Address all correspondence to: nurul.amran@utp.edu.my

1 Chemical Engineering Department, Universiti Teknologi PETRONAS,

2 HICOE – Center for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Department of Chemical Engineering, Universiti Teknologi PETRONAS, Seri Iskandar, Perak, Malaysia

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

**Acknowledgements**

**Conflict of interest**

**Author details**

**155**

Seri Iskandar, Perak, Malaysia

provided the original work is properly cited.

PETRONAS for the support.

**5. Conclusions**

Basically, there are three stages involved in the process [32]. The first stage is heavy phase separation, where separated oils and solids are removed. In the second stage, the bacteria are used to convert the emulsified oil into non-harmful end products. This stage is known as emulsified oil degradation stage. Then, the third stage contains clarifier in order to remove the remaining solids and water.
