Physicochemical assessment and treatment of produced water: A case study in Niger delta Nigeria

The most important waste stream created during oil and gas production is oilfield-produced water. When discharged without treatment, it poses a significant risk of pollution of marine ecosystems. While adequate treatment before disposal is acceptable, achieving authorized discharge criteria continues to be a problem for the petroleum sector. This research examined the physicochemical characteristics of produced water at various month intervals before and after treatment. Heavy metal and organic component concentrations in water samples were determined using atomic absorption spectroscopy and gas chromatography. The results indicate that produced water from a certain Niger Delta oilfield contains significant amounts of heavy metals and some organic compounds after treatment. The present laws, as well as the measurement of dispersed oil and grease content, have been in place for a long period of time without considerable change, even though most dangerous components in produced water are dissolved. It is recommendable for the prospective field developers/operators to consider the dissolved components of produced water and consider the economic consequences of adopting tertiary produced water polishing technologies.