Location of Repository

Physical modelling of colloidal slurry flows

By D. Harbottle


The study looks at the rheology and pipeline flow properties of colloidal suspensions dispersed in electrolytes of different concentration and type. Fuso silica spheres (0.8pm) form the dispersed phase of the suspension, and KN03, KCI electrolytes the continuous\ud phase. The strength of the particle-particle interaction is significantly influenced by the electrolyte concentration. An increase in the electrolyte concentration from 10 4M to IM results in the formation of aggregates, thus influencing the sedimentation, sediment bed structure and pipeline transportation properties. Silica aggregates formed in IM\ud electrolytes are on average 5.75 times bigger than the primary particle. Pipeline transportation studies have shown the aggregated suspension to have a lower minimum\ud transport velocity than the dispersed suspension. Such behaviour is believed to be related to interfloc flows within the aggregate, enhancing the level of fluid turbulence.\ud \ud The centre-line and near wall turbulence intensities are enhanced in the presence of aggregates, while dispersed suspensions have negligible effect on modulating the fluid\ud turbulence. Measurement of the streamwise RMS shows two critical Reynolds numbers with increasing flow velocity. The first critical Reynolds number (Re = 5500) occurs when\ud the RMS profile of the aggregated suspension diverges (exceeds) from the RMS profiles of the dispersed and single phase flows. This enhancement is thought to be related to interfloc flows. A second critical Reynolds number (Re = 8000) is identified when the RMS profile of the aggregated suspension begins to converge with the dispersed and single phase RMS profiles. Convergence of the RMS profiles is related to the break-up of aggregates once a critical fluid shear stress is exceeded. Aggregate break-up data is verified with results collected using a Bohlin CVO-R rheometer

Publisher: School of Chemical and Process Engineering (Leeds)
Year: 2008
OAI identifier: oai:etheses.whiterose.ac.uk:673

Suggested articles



  1. Near-wall particle lift and deposition in slurry pipelines. doi
  2. Modern conceptions of the mechanics offluid turbulence.
  3. The structure of turbulent boundary layers. doi
  4. (1955). Characteristics of turbulence in a boundary layer iviih zero pressure gradient. National Advisory Committee for Aeronautics,
  5. (1972). Turbulence Phenomena: An introduction to the eddy transfer of momentum, mass, and heat, particularly at interfaces. doi
  6. Scaling lawsforpipe-flow turbulence. doi
  7. Investigation of solid-liquid pipe flow with regard to turbulence modification. doi
  8. Effect of particle size on modulating turbulent intensity. doi
  9. Turbulence modification byparticles in a horizontal pipe flow. doi
  10. Turbulence modulation in homogeneous dilute particle-ladenflows. doi
  11. LD V measurements of an air-solid livo phase flow in a horizontalpipe.
  12. The effect of small particles on fluid turbulence in a flat-plate, turbulent boundary layer in air. doi
  13. Turbulence modiji'cation in a homogeneous turbulent shearflow laden with small heavy particles. doi
  14. Experimental study of the floiv properties of a homogeneous slurry near transitional Reynolds numbers. doi
  15. On a turbulence modelfor slurryfloiv inpipelines.
  16. Heat transfer in solid-liquid suspensions in total pumpable concentration range.
  17. (1953). The structure of turbulence in fully developed pipe flow. National Advisory Committee for Aeronautics,
  18. Deposition of liquid or solid dispersion from turbulent gas streams; a stochastic model. doi
  19. Particles-turbulence interaction. doi
  20. Theoretical approach on the turbulence intensity of the carrierfluid in dilute two-phaseflows.
  21. (2004). Fluid-solid interaction in particle ladenflows.
  22. On predicting particle-laden turbulent flows. doi
  23. 3-D turbulence structure andphase distribution measurements in bubbly two-phaseflows.
  24. (1974). Vortex sheddingfrom spheres. doi
  25. Floc breakup along centerline of contracifle flow to orifice. Colloids and Surfaces, doi
  26. (1973). On transition in a pipe. Part 1.77? e origin of puffs and slugs and theflow in a turbulent slug. doi
  27. On transition in a pipe. Part Z Tile equilibrium puff doi
  28. (2001). Transition to turbulence in non-Newtonian pipeflow. 6th World Congress of Chemical Engineering
  29. Surface chemistry-rheology relationships in concentrated mineral suspensions. doi

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.