Combined coagulation-electrocoagulation process using biocoagulant from the Opuntia ficus-indica for treatment of cheese whey wastewater.

This work reports a combined coagulation-electrocoagulation process using a biocoagulant from the Opuntia ficus-indica for treatment of cheese whey wastewater. The process parameters as pH, biocoagulant dosage, and current density were evaluated from the chemometric tools. A Box-Behnken design was used, having as responses the removal percentages of turbidity and chemical oxygen demand (COD). The results showed that for the studied variable ranges, linear models were obtained and the pH was parameter more significant for treatment proposed. The pH showed synergic effect with the investigated parameters, while the biocoagulant dosage and density current showed antagonistic effects. The desirability function was used to optimization of process, and suggested values were pH 10.0, biocoagulant dosage of 4.4 g L-1, and current density of 31.5 mA cm-2, which showed removals of turbidity and COD of 98.9 and 83.8%, respectively.

Biodepuration of domestic sewage, textile effluents and acid mine drainage using starch-based xerogel from recycled potato peels.

Water is a finite resource. Its safety and cleanliness are highly important to meet current and future human needs. Compared to other resources, water represents a main factor to achieve development in several areas and leads to economic progress of a nation. However, in recent years, the excessive demographic and industrial growth has exacerbated water contamination. In this study, the biodepuration process of domestic sewage (DS), textile effluents (TE) and acid mine drainage (AMD) is conducted using starch-based xerogel from potato (Solanum tuberosum) peels. Results showed that the treatment is effective to achieve the reduction of 5-day biochemical oxygen demand. The most important result was the achievement of heavy metals removal for the three components. Firstly, there was a reduction of barium, zinc, and cadmium (91, 60 and 46%, respectively) for raw AMD. Secondly, there was a reduction in the levels of zinc, aluminum, and barium (89, 86 and 64%, respectively) for TE biodepuration. Finally, results showed a reduction in zinc, iron and cadmium levels (81, 78 and 57%, respectively) for DS biodepuration.