Optimización de los procesos de potabilización mediante floculación por lechos porosos. Proyecto experimental en planta piloto construida en el Laboratorio de Sanitaria

Abstract

In this research we studied flocculation in a porous bed, through the construction of a pilot model on a laboratory scale. It has a flocculation column composed of three serial beds of different particle sizes, through which the coagulated water flocculates and partially settle. The tests were carried out on water samples from the four rivers of the Cuenca city, which have different physical characteristics. The results of the tests allowed to determinate design parameters for this process such as coagulant doses, flocculation times, velocity gradients and flocculation speeds. The control parameters used in the experimental part were: turbidity at the exit of each bed; color and turbidity of sedimented water, and color and turbidity of filtered water. The results showed significant efficiencies in the removal of color and turbidity of raw water, reaching the levels required by the Ecuadorian Institute of Standardization (INEN). It was possible by means of the 1108 statute that establishes the quality requirements for water intended for human consumption, which is color less than 20 UC (PtCo), and turbidity less than 5 NTU. The results indicate the feasibility of implementing this flocculation mechanism to improve the process of water treatment in the Andean region, which has low temperatures, high concentrations of colloids and requires a chemical process for destabilization. Also, this mechanism possibly reduces the costs of construction, operation and maintenance of flocculators. Furthermore, in this system the retention time and the loss of load are considerably less than in the conventional ones.