High Float Emulsion Residue: Its Unique Rheology and Microstructure

Despite the clear benefits of High Float (HF) emulsions, current formulations are not optimized. The design of "next genereation" emulsions will require knowledge of the basic science that underlies HF systems. At present, the understanding of HF emulsions is rudimentary in two regards: i) No rheological model is available to predict the flow/deformation of HF materials. The only semi-quantitative characterization is whether the breakthrough time in a float test would exceed 20 minutes; ii) The mechanism(s) by which the stabilizer (tall oil soap) gives rise to the unique rheology of HF residues is not understood. This paper reports a detailed study of the rheology of HF residues. The most notable feature of this material is its yield stress, which can be quantified using a stress-ramp procedure. A rheological model - a hybrid between Bingham fluid and Kelvin-type solid - is developed to predict the ramp response of the residue material. It is proposed that the yield stress, rather tha te breakthrough time in float tests, should be the metric for characterizing HF residues and other similar materials. In addition to rheological studies, we speculate also on the microstructure of the HF residue, and how it leads to the material's macroscopic behaviour.

Language

  • English

Media Info

  • Media Type: Print
  • Pagination: pp. 215-236.
  • Monograph Title: Proceedings of the Sixth-First Annual Conference of the Canadian Technical Asphalt Association (CTAA): Banff, Alberta

Subject/Index Terms

Filing Info

  • Accession Number: 01647328
  • Record Type: Publication
  • Source Agency: Transportation Association of Canada (TAC)
  • Files: ITRD, TAC
  • Created Date: Sep 28 2017 12:25PM