The results presented in Fig. 5a, b and c show the surface responses of Cmax, colour and COD removal due to WC and SBC.
The results indicates that the SBC concentration did not influence significantly the responses of Cmax and the removal of colour and COD.
However, the linear effects of WE concentration evidenced significant influences in the answers of Cmax (p> 0.05). Largest lmax, Cmax were obtained in the small WE concentration added, in the order of 8.5%, while highest colour and COD removals were obtained in the other level of WC (17.5%).
Parallel to the largest lmax and Cmax, the maximal algal dry weight records were observed.