Wastewater Effluents at Sierra Leone Bottling Company Limited: Composition, Assessment and Removal Efficiency of Physico-chemical Parameters

摘要

The analyses of industrial effluents at Sierra Leone Bottling Company Limited (SLBC) in Freetown, the capital city of Sierra Leone were conducted to assess its composition, and removal efficiency of physico-chemical parameters. Fifteen (15) samples were collected from the drain water (influent), pre treatment effluent and treated effluent (effluent) for five days. There were significantly higher concentrations of influents parameters relative to those of the corresponding effluents. The influent levels for pH, electrical conductivity and chloride were higher than permissible threshold. 80% of the samples at the influent point were within permissible guideline for TDS but all were in total agreement with the effluent samples for the same parameter. Comparative analyses showed significant reduction in values for pH, temperature, iron and chromium in the effluent samples relative to the influent samples and all of the other parameters did not show any statistically significant differences. The treatment plant was noted to be highly efficient in removing iron and chromium but least efficient for total dissolved solids and water temperature. Huge variances with respect to removing contaminants for chloride, electrical conductivity and total dissolved solids were observed. The average overall removal efficiency of contaminants in industrial effluents was low but the practice of treating industrial wastewater by SLBC was plausible. Considering the pollution load of certain parameters being investigated, it is imperative for the SLBC to initiate the process of setting up waste stabilization ponds (WSP) so as to contain industrial effluents for further examination before they are discharged into the environment.