DETERMINACION DEL TIEMPO DE RETENCION Y CARACTERISTICAS HIDRAULICAS CON CLORURO DE SODIO COMO TRAZADOR EN UNA LAGUNA DE ESTABILIZACION

Abstract

This article discusses the methodology used to determine the retention time of the lagoon system of the pilot plant of the Regional School of Sanitary Engineering and Water Resources – ERIS- of Guatemala. The procedure used to determine the retention time of the lagoons was obtained through the application of Sodium Chloride (NaCl) or common salt as a tracer substance, which was applied at the entrance of the lagoon with a known concentration and measured at the exit with a conductivity meter every 12 hours for 44 days. The concentration values obtained are processed and plotted in function of the time lapsed and using mathematical models we obtain the hydraulic characteristics of the lagoons, type of flow, dead zones, and short circuit. With the testing we obtained that the retention time of stabilization of the lagoon is 23 days and in the maturation lagoon is 36 days. Comparing these results with the values of the theoretical retention times we have a difference of 3 more days in the stabilization lagoon and 7 more days in the maturation lagoon, furthermore the two lagoons operate with a piston flow and a mixed flow in a 1:4 relation.