Utilisation of Oyster Shells Powder as Low-Cost Adsorbent for the Removal of Selected Pollutants from Oilfield Produced Water

The study demonstrates the presence of high concentration of both organic and inorganic pollutants in produced water highlighting the need for treatment prior to re-use or disposal. Some pollutants like PAHs and phenolics are potentially mutagenic and carcinogenic, making them of great concern globally. While technologies currently exist for treating produced water, companies are researching cheaper, eco-friendly and efficient methods for produced water treatment. This study demonstrates the utilization of naturally occurring biowaste (oyster shells) from mariculture for the removal of pollutants in produced water, a byproduct of oil production. Oyster shell primarily composed of over 96% calcium carbonate, was utilized for the treatment of oilfield produced water samples from an oilfield in Bayelsa State, Nigeria. The study evaluated the removal efficiency of pulverized oyster shells (POS) for the treatment of oilfield produced water samples for petroleum hydrocarbon and dissolved solids. Produced water samples AZ-ST1, AZ-ST2, and C7T were allowed to pass through a column of pulverized oyster shells within a contact time of 30, 60 and 90 minutes. Produced water samples AZ-ST1, AZ-ST2, and C7T were passed through column of POS, after contact time of 30, 60 & 90 minutes, the filtrates were analyzed for total petroleum hydrocarbon and total dissolved solids. Consequently, the POS removal efficiency was computed to be 73.0%, 79.8% & 88.1% for TPH and 77.2%, 79.1% & 79.7% for TDS in samples AZ-ST1, AZ-ST2, and C7T respectively. Therefore, POS, as a low-cost biowaste material, shows potential for removal of pollutants from oilfield produced water.