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FLIP
Abstract
The research involved proposing a methodology to separate the phases (particle size) of a Colombian diatomaceous soil after placing it in columns with different aqueous media (water and hexametaphosphate) and subsequently subjecting it to agitation and sedimentation processes, varying over time (3 and 7 days). Samples were extracted from each column at different heights, which presented distinguishable physical properties in tests of specific gravity, consistency, hydrometry, Scanning Electron Microscopy, and oedometer consolidation. Some of the most efficient techniques for particle separation involve the displacement of solid particles in fluid media. The results showed a reduction in the liquid and plastic limit values with deeper sections, that is when the material was thicker. The LL values for the columns at 3 days, on average, were higher than those for the columns at 7 days. The highest Gs values corresponded to the material in section S1 of each column, that is, the samples with the lowest liquid limit and largest particle size. In all cases, section No. 1 of each column presented hydrometry curves lower than the other sections; that is, it reported larger particles. In the separation of particles by size, it was concluded that the effect of time and multiple agitation cycles had a greater impact, while the type of aqueous medium did not. In the samples treated with water, the void ratio increased, while the opposite occurred with the samples containing hexametaphosphate. The initial and final void variations did not exceed 10%. The SEM results do not allow for changes in particle size distribution between the different sections of each column to be recognized; the effect of sedimentation is more clearly validated in the hydrometry curves.
