Effect of eggshells for the harvesting of microalgae species

Figures & data

Figure 1. Procedure for C. vulgaris flocculation by eggshells.

Figure 2. Growth curve of C. vulgaris.

Figure 3. Separation efficiency of C. vulgaris at different pH.

Figure 4. Separation efficiency of C. vulgaris with different eggshell doses (at pH 6).

Figure 5. Change in zeta-potential at different eggshell doses.

Table 1. Separation efficiency at different mixing rate and mixing time.

Mixing rate (r/min)*
	10	30	50	70	100	150	200	250	300
Separation efficiency (%)	62	80	88	95	98	99	96	94	90
Mixing time (min)**
	5	10	15	20	30	40	60	80	100
Separation efficiency (%)	90	94	97	99	100	100	100	100	100

Note: All experiments were performed at 80 mg/L eggshell concentration and pH 6.

*At optimized settling time (20 min) and mixing time (20 min).

**At a mixing rate of 150 r/min.

Figure 6. Relationship between separation efficiency and settling time of C. vulgaris in the presence of various concentrations of eggshells.