Rheology of un-sieved concentrated domestic slurry

Rheology of un-sieved concentrated domestic slurry: a wide gap approach

Thota Radhakrishnan, A.K. (TU Delft Sanitary Engineering)
van Lier, J.B. (TU Delft Sanitary Engineering)
Clemens, F.H.L.R. (TU Delft Sanitary Engineering; Deltares)

2018-09-20

Information on the rheology of domestic slurries is essential in designing pipeline transportation in novel sanitation systems. As concentrated slurries in their original collected state have wide particle size distribution, with particles up to 2 mm, a wide gap rheometer is used to acquire the rheograms. Rheograms obtained from a wide gap rheometer require a method to convert the rotational velocity to the shear rate, and this method must be robust to noisy data and yield stress in the slurry. For this purpose, a Tikhonov regularisation method is chosen as it suits the criteria the best. Using this, the rheograms are obtained for various total suspended solids (TSS) concentrations of slurries. A Herschel-Bulkley rheological model is used to represent the rheology of the slurries. The influence of the change in concentration of the slurries is represented through its influence on the Herschel-Bulkley parameters. The consistency index K exponentially increases with the concentration. The yield stress τy , is 0 at low concentrations, and above 2.0% TSS (wt./wt.) exponentially increases with the concentration. The behaviour index n , is 1 at low concentrations, and above 2.6% TSS (wt./wt.) it decreases in an inverse power law with the concentration to reach a sort of plateau.

concentrated domestic slurry
un-sieved slurry
rheology
Couette inverse problem
concentration influence

http://resolver.tudelft.nl/uuid:0e4b4907-00ef-410b-b871-0dd0cbb8f15f

https://doi.org/10.3390/w10101287

2073-4441

Water, 10 (10)

Institutional Repository

journal article

© 2018 A.K. Thota Radhakrishnan, J.B. van Lier, F.H.L.R. Clemens