A Comparative Study of the Performance of Water Hyacinth (Eichhornia Crassipes) and Water Lettuce (Pistias Stratiotes) in the Remediation of Produced Water

Abstract

The study presents the characteristics of produced water obtained from a detention pit in the Niger Delta region of Nigeria. Phytoremediation, an emerging remediation technology for contaminated soils, groundwater, surfacewater and wastewater that is both low-tech, low-cost, and environmental friendly have been employed in this study. Two aquatic macrophytes: water hyacinth (Eichhornia crassipes) and water lettuce (Pistias stratiostes) have been used to remediate this produced water harmless in the environment. The two aquatic macrophytes were comparatively studied to determine their effectiveness in remediation without the use of fertilizers to sustain their growth. Also, physico-chemical parameters were compared with standard discharge limits stipulated by the Department of Petroleum Resources (DPR). Parameters such as pH, EC, salinity, TDS, TSS, DO, BOD, COD, turbidity, sulphate, phosphate, ammonia, oil and grease, Cu, Pb, Cr, Zn, Fe, and total coliform of the produced water have been studied using standard protocol of APHA and ASTM. The physico-chemical analysis revealed that most of the parameters were above the permissible limits and that water hyacinth made a better clean up than water lettuce. One-way ANOVA analysis of variance was used to test for significant difference. Recommendations were also made for better cleanup goals and plants survivals.

Keywords: produced water, phytoremidiation, aquatic macrophytes, water lettuce, water hyacinth, contaminants.