Assessment of Physicochemical Qualities of Oilfield Wastewater in Bayelsa State, Nigeria

Abstract

Oilfield wastewater which is not properly treated before being discharged has great negative impacts on the environment and aquatic life and also affects humans. It is necessary to assess the physicochemical qualities of oilfield wastewater to reduce its environmental impact. Oilfield wastewater samples were collected from an onshore oil production platform for a period of eight months (March to October, 2018). These were analyzed for physicochemical parameters and heavy metals using standard methods. Oilfield wastewater gotten from EPU 05 had higher TDS 294.6 mg/l, conductivity 619.0 μS/cm, COD 6.44 mg/l, BOD 2.24, compared to that found from Kolo creek flow station and were significantly different (P>0.05). While, TSS 16.85 mg/l, salinity 175.0 mg/l, turbidity 4.8 (NTU), and THC 1.39 were higher in that of the Kolo creek flow station. There was no significant difference in pH and temperature in the Kolo creek flow station and EPU 05. Higher values of iron 0.46 mg/l, chromium 0.03mg/l, was observed in that of the Kolo creek flow station compared to that of the EPU 05 0.14mg/l. EPU 05 had higher values in zinc 0.09 mg/l, copper 0.12 mg/l, cadmium 0.18 mg/l, mercury 0.08 mg/l and arsenic 0.07 mg/l. All the physicochemical parameters were within the allowable limit recommended by regulatory bodies (eg. WHO, DPR, FMEnv etc.). Regulatory bodies should ensure that companies practice proper waste management and compliance.