Performance of Chlorella vulgaris for the Removal of Ammonia-Nitrogen from Wastewater

In the present investigation, the efficiency of Chlorella vulgaris (C. vulgaris) was evaluated for the removal of ammonia-nitrogen from wastewater. Eight different wastewater samples were prepared with varied amounts of NH 4 -N concentrations from 15.22 to 205.29 mg/L. Experiments were conducted at pH 7.5 0.3, temperature 25C 1C, light intensity 100 E/m 2 /s, and dark-light cycles of 8-16 hr continuously for 8 days. From the results, it was found that NH 4 -N was completely removed by C. vulgaris, when the initial concentration was between 5.22-25.24 mg/L. However, only 50% removal was obtained when the NH 4 -N concentration was 85.52 mg/L, which further decreased to less than 32% when the NH 4 -N concentration exceeded 105.43 mg/L. The further influence of nitrogen on chlorophyll was studied by various NH 4 -N concentrations. The maximal value of chlorophyll a (Chl a) content was found to be 19.21 mg/L for 65.79 mg/L NH 4 -N concentration, and the maximum specific NH 4 -N removal rate of 1.79 mg/mg Chl a/day was recorded at an NH 4 -N concentration of 85.52 mg/L. These findings demonstrate that C. vulgaris could potentially be employed for the removal of NH 4 -N from wastewater.