Turbidity and Colour Reduction of Pond Water Using Extracts of Diospyros mespiliformis, Mitragyna inermis, Piliostigma reticulatum and Tamarindus indica in Northern Nigeria

Abstract

The study examined the coagulation performance of leaves and root bark extracts of Diospyros mespiliformis, Mitragyna inermis, Piliostigma reticulatum and Tamarindus indica. The plant materials were collected along River Kubwa in Damboa local Government area of Borno State, Nigeria. The crude extracts of these plant materials were prepared based on soxhlet method using soxhlet solvent extractor. About 400mg of each pulverized sample was used for the extraction process. Three (3) liters of distilled water was used for the extraction process. The extracts were each added to highly turbid (422 NTU) pond water samples at various dosages of 60, 75, 90, 105, 120, and 135mg/l and a conventional coagulation-flocculation jar tests were conducted. The nature of the flocs formation for all the plant extracts were observed to be smoky rather than aggregating into denser masses and resulted in turbidity and colour removal efficiencies of 0.71-18.57% and 1.17-22.38% respectively. The coagulation activities were subjected to T-Test Analysis and it indicated that there was statistically (P< 0.05) significance difference at different concentrations. The results also revealed slight decrease in pH in the range of 8.1-7.55 exhibited by all the extracts. From the results of the turbidity and colour removal efficiencies, it can be concluded that these plant materials have the potential of improving the quality of pond or surface water (which most rural communities in developing countries depend for many purposes) that are heavily turbid; However, for them to perform effectively, a coagulant aid is required.