Optimización del proceso de coagulación-floculación en el tratamiento de agua residual generada en la cuba de decapado en la empresa Galvánica Cía. LTDA. del cantón Cuenca

Abstract

The present work was carried out in the company GALVÁNICA CIA. LTDA., located in the city of Cuenca. The objective of the study was to optimize the coagulation-flocculation process in the treatment of residual water in the capping tank. For which, jar tests were carried out by applying three different coagulants (aluminum sulfate, ferric chloride and polyaluminum chloride) in the wastewater, once the pH was adjusted. The concentration of iron and aluminum in raw water, water with pH adjustment and water treated with the different coagulants was evaluated. The results obtained after the jar tests indicated that the coagulant with the highest percentage of removal was aluminum sulfate, showing a removal of 97.69% and 92.81% of iron and aluminum, respectively. The use of this coagulant is feasible for the company because its cost makes it economically profitable. For the statistical analysis, MANOVA was obtained to verify the relationship between the percentages of removal of metals (iron and aluminum) with respect to the type of coagulant used, concentration and dose of each coagulant and the pH of the wastewater; Through this statistical analysis it was also possible to determine that the best coagulant to use is aluminum sulfate since it gives us better results in iron and aluminum removal. In the statistical results it was possible to show that there is a direct relationship between the percentage of metal removal and the type of coagulant, its concentration and the pH of the water to be used. It will be extended that aluminum sulfate should apply a concentration of 10% for wastewater with a pH of 5.5. In addition, ANOVA was also applied to check if there is any relationship between the three types of coagulants and the removal of iron and aluminum. Based on the application of Tukey-HSD, it was possible to determine that there is no relationship between the coagulants, since each one acts differently in relation to the established parameters.