Phycoremediation of Laundry Wastewater Using Chlorella vulgaris (Beijerinck)

Abstract

A study of the effect laundry wastewater on the microalga Chlorella vulgaris was carried out. The study was carried out using different treatments 0% (control), 5%, 10%, 20%, 30%, 40%, 50% of laundry wastewater. The microalgal growth responses were determined optically using absorbance on spectrophotometer at 750nm. Samples were analyzed for physicochemical parameters such as pH, temperature, total dissolved solids, conductivity, biochemical oxygen demand and chemical oxygen demand using standard methods. Descriptive statistics, inferential (One-way analysis of variance (ANOVA) and post-hoc test Duncan multiple range (DMR) were done using Microsoft excel 2010 and statistical package for social science SPSS 22. The results showed that different concentrations of laundry wastewater stimulated the growth of Chlorella vulgaris with 50% treatment having the highest yield (3.2), followed by 40% treatment (2.7) and the control (0%) had the least yield of 0.6. There was a significant increase in pH and temperature while there was a decrease in total dissolved solids, biochemical oxygen demand, chemical oxygen demand and conductivity. The level of reduction in COD was from 1340mg/L to 364mg/L, which indicated that Chlorella vulgaris has the potential to bioremediate laundry wastewater.