Oil and gas production is usually accompanied by water (brine), which is referred to as produced water. As oil and gas production declines, the quantity of water production from same reservoir increases. These produced waters have many components, which mostly have adverse environmental impacts. One of such components are the heavy metals which are numerous. Produced water sample from Niger Delta crude oil was investigated for five (5) heavy metals. The analysis was carried out using an Ultraviolet Visible Spectrophotometer. The analysis was carried out (in line with industry standard) on the produced water sample in order to determine the concentrations of the heavy metals present. The results obtained from this analysis showed that the concentrations of one out of the five heavy metals investigated (Arsenic (As)) was more than the allowable limits set by regulatory bodies. Arsenic (As), Boron (B), Manganese (Mn), Tin (Sn), and Barium (Ba) have concentrations of 0.9599mg/L, 0.0955mg/L, 0.000433mg/L, 0.31730mg/L, and 0.0019mg/L respectively compared with maximum limits set by the regulatory bodies as 0.3mg/L Arsenic, 5mg/L Boron, 0.004mg/L Manganese, 10mg/L Tin and 1.3mg/L Barium. This showed that the produced water from oil and gas activities in Niger Delta region of Nigeria should be tested and treated for Arsenic and other present heavy metals that may have concentrations higher than standard limits set by regulatory bodies before disposal and/or re-use.
Keywords: Heavy Metals, Niger-Delta, Produced water, crude oil
