Metodologia para investigação de colmatação de filtros de barragem de terra: estudo piloto

Abstract

Studies on the clogging of filters of earth dams have had strong expression in Brazil in the last decades. The obstruction of the drainage systems can occur by physical, chemical or biological agents; due to obstructing compounds such as oxides, hydroxides or even microparticles of clays carried by the drainage water. The accumulation of these stable compounds, which evolve over time, tends to fill the voids of the filters and drains, reducing their permeability, altering their original characteristics and leading to the increase of the subpressions in the dam. In this sense, the objective of this work was to start the development of a prototype to monitor indicative parameters of physical and biological clogging of artificial sand filters. The system consists of constant load columns adapted for reuse of water, with constant flow and automated. The artificial sand is constituted of crushed basalt, by the greater availability of iron in the system, as well as by its application in filters of regional dams. The water of the system was collected in the São Francisco River located in the city of Toledo-PR to evaluate possible colmatative processes. On the monitoring parameters, pH, electrical conductivity, turbidity, total solids temperature counting of colony forming units (UFC) were analyzed for this study. The results obtained allowed to observe a variation of the physical-chemical conditions between the columns of elaboration and the microbiological development, during the period of analysis.