Diseño a escala piloto de un sistema de eliminación de fenoles en aguas residuales de una empresa textil empleando dióxido de cloro

Abstract

This study had an objective to design a pilot scale of a system of elimination of phenols in wastewater from the textile industry using chlorine dioxide level. To develop the project, it worked experimentally on electron accelerator laboratory of the EPN, it worked with composite samples collected by previous samples of the wastewater in the textile company, the wastewater at different pH was adapted to determine the range that best range which acted better the chlorine dioxide in aqueous solution, thus to determine the best working conditions for the removal of phenols. A factorial experimental design was presented 3 x 3 whose pH levels were 5, 7 and 9 of the wastewater and to the chlorine dioxide concentration 2.5%; 6.5% and 10% stabilized in aqueous solution. It worked with two repetitions and had as output variable the final concentration of phenols. Trough statistical analysis made with data got experimentally, it was determined in the laboratory during the treatment of wastewater with chlorine dioxide by a contact time of 30 minutes. It got a better removal of phenol when the water was at pH 9 and chlorine dioxide at a concentration of 10%. Under those conditions, a percentage of phenol removal of 90.49% was obtained. The study of the kinetics of reaction between the phenol present in the waste water to pH 9 and chlorine dioxide stabilized in aqueous solution 10% was performed using the integral method for determining order of reactions was shown that is second order with a constant reaction rate of 0.541 L x mg-1 x min-1. It was designed to scale pilot the removal system phenols present in the wastewater able to treat 8000 L / day it was made a cost comparison was performed by using hydrogen peroxide whose concentration is 10%. The pilot system design for removing of phenols present in 1 m3 of wastewater scale with a contact time of 30 minutes with chlorine dioxide gave a final phenol concentration of 0.051 mg / L, therefore it meets the Standard Technical Environmental Quality for discharging of wastewater into the sewage system that allows a maximum of 0.2 mg / L of phenol as set forth in the TULSMA.