Methodological considerations for studying self-weight fluidization in a sedimentation column

摘要

The objective of this research is to develop a laboratory methodology that facilitates an improved understanding of self-weight fluidization in a batch column. Observations of the fluidization pipes and of the mudline interface are made by means of a digital camera, naked eye and gamma radiation source through repeated runs for a pure kaolinite-water mixture under different initial concentrations and initial suspension heights. Analysis of the experimental results show the onset of self-weight fluidization occurs at an earlier period, during the first falling rate than the second falling rate which has been reported by others. Despite the formation and upward propagation of fluidization pipes no inflection points are observed anywhere atop the mudline interface for the kaolinite mixture. Numerical simulations made via a 1-D sedimentation model that accounts for the upward propagation of fluid further validate the observation of the authors that for the kaolinite mixture, self-weight fluidization cannot be always detected by observing the mudline interface.