Trace metal analysis of oilfield-produced water from Clair ridge offshore platform using microwave plasma atomic emission spectrometry

Oilfield Produced water, a by-product of oil and gas production, often contains a range of dissolved and suspended constituents that may pose environmental concerns if discharged untreated. In this study, Microwave-Induced Plasma Atomic Emission Spectroscopy (MIP-AES) was employed for the quantitative determination of trace metals in produced water samples. Calibration curves for all analyzed elements exhibited excellent linearity (R² ≥ 0.999), confirming the method’s accuracy and suitability for multi-element analysis. The concentration of sodium was found to be 2596.03±43.20 ppm, indicating high salinity, consistent with the known saline characteristics of the North Sea water often injected into reservoirs. Significant levels of copper, iron, and potassium were also detected, suggesting possible contributions from natural formation water chemistry, mineral dissolution, and corrosion of production infrastructure. The lack of phosphorus detection was probably caused by either chemical transformation into undetectable forms or concentrations below detection limits. The findings demonstrate that MIP-AES is a sensitive, economical, and reliable method for routinely monitoring the quality of produced water, with consequences for environmental management and discharge regulation compliance.