Journal of Central South University

, Volume 24, Issue 5, pp 1207–1216 | Cite as

Dynamic simulation of pilot thickener operation using phenomenological model with results validation for continuous and discontinuous tests

  • Rahimi Mehdi
  • Unesi Majid
  • Rezai Bahram
  • Abdollahzadeh Ali
Article
  • 34 Downloads

Abstract

The phenomenological theory of sedimentation-thickening processes predicts the settling behavior of a flocculated suspension in dependence of two functions, the batch flux density function and the effective solid stress. These functions were determined using batch settling tests. The governing equations for sedimentation were then solved numerically for these functions and the predictions were compared to the experimental results from pilot scale thickener tests. Firstly, the continuous tests were performed in the plexiglass pilot thickener at different feed flow rates and discharge rates and the solid volume fraction of discharge, the bed height and the time were recorded for each condition. These tests were also simulated and it was observed that there is a good agreement between the results of continuous tests and the results of dynamic simulation. Secondly, the discontinuous tests were performed in the plexiglass pilot thickener at different feed flow rates with a discharge rate of zero. The bed formation rate was determined for each condition. These tests were also simulated and it was observed that there is a good agreement between the results of discontinuous tests and the results of simulation.

Key words

dynamic simulation dewatering thickener behavior pilot thickener validation 

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Copyright information

© Central South University Press and Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Rahimi Mehdi
    • 1
  • Unesi Majid
    • 2
  • Rezai Bahram
    • 1
  • Abdollahzadeh Ali
    • 1
    • 3
  1. 1.Department of Mining and Metallurgical EngineeringAmirkabir University of TechnologyTehranIran
  2. 2.Young Researchers and Elites Club, Science and Research BranchIslamic Azad UniversityTehranIran
  3. 3.Department of Mining EngineeringUniversity of KashanKashanIran

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