Environmental Impacts of Produced Water Potential Discharge: A Case Study of Umuechem/Umutu Oil Fields, Niger Delta, Nigeria

摘要

The physico-chemical properties and the concentration of trace metals such as Cu, Cr, Fe, Pb, Ni, Zn, Mn of eight produced water samples from two producing oil fields in Niger Delta, Nigeria were investigated to delineate the impact of their discharge into the environment. The result showed that pH ranged from 5.21 to 8.35; conductivity ranged from 70.00 to 147.00 μS cm~(-1), TDS ranged from 364.00 to 2,682.00 mg L~(-1); Cl~- ranged from 1.78 to 10.65 mg L~(-1); SO_4~(2-) ranged from 0.55 to 5.01 mg L~(-1); PO_4~(3-)ranged from 0.37 to 6.22 mg L~(-1); turbidity ranged from 25.00 to 162.00 NTU; oil and grease ranged from 0.50 to 10.50 mg L~(-1); NH3-N ranged from 0.41 to 1.62 mg L~(-1); phenols ranged from 0.01 to 0.16 mg L~(-1); alkalinity ranged from 0.01 to 3.60 mgL~(-1). The concentration of Fe~(2+) and Pb~(2+) were above the set regulatory limit. Principal component analysis and cluster analysis applied to the variables gave four major components and clusters, respectively. The principal component analysis showed that the eigenvalues of the four first principal components represent up to 83.90% of the total variance (PC1 44.40%; PC2 15.70%, PC3 13.50%, PC4 10.30%) of the observations, suggesting that four principal components adequately explain the variation in the data set. Hierarchical cluster analysis grouped the variables into four clusters based on similarity of the produced water quality characteristics. The significant agreement between PCA and CA multivariate statistical techniques suggests that these methods are valuable in analyzing these variables in the produced water samples.