Análise granulométrica influenciada pela qualidade da água e dispersantes químicos

Abstract

In order to obtain reliable results on the textural analysis is necessary that soil dispersion is complete and continued stability of the disperse phase. The objective was to test the use of three types of water: - mineral, tap ("hard water") and ultrapure water - and compare the sodium hydroxide (NaOH) and potassium hydroxide (KOH) as the chemical dispersants in order to determine its effect on texture analysis. A texture analysis by the pipette method was performed, applying an adapted methodology from the Manual of Soil Analysis Methods. To the sand fraction was no significant interaction (P<0.05) between water quality and the dispersing agent. There was no interaction between the factors studied in clay and sand fractions, however, there were differences in the quality and the dispersing agent. For all the best result fractions occurred when using ultra pure water and NaOH stood out as more efficient dispersant. The relatively better efficiency of NaOH can be explained due to its ionic radius hydrated be greater and best separates the clay. There was a relationship between the electrical conductivity of water and clay dispersion, and the lower the conductivity, the better was dispersion. The use of mineral water or tap water from Campus Sete Lagoas ("hard water") resulted in lower soil dispersion. The dispersant power of NaOH was significantly greater than that of KOH.