Obtaining the steady shear rheological properties and apparent wall slip velocity data of a water-in-oil emulsion from gap-dependent parallel plate viscometry data

Rheological properties related to the extrusion of polyolefins are the shear viscosity, the elongational viscosity, the slip velocity and their temperature- and pressure-dependencies. These properties are measured in the rheology lab mainly via a parallel-plate rheometer and a capillary rheometer. Then appropriate rheological models have to be used to account for all these properties. Such models are either viscous (e.g., the Cross model) or viscoelastic (e.g., the K-BKZ model). The latter gives the best fitting of the experimental data and offers excellent results in numerical simulations, especially in extrusion flows. Wall slip effects are also found and measured by rheometric flows. Modeling of extrusion flows should make use of appropriate slip models that take into effect the various slip parameters, including the effects of shear stress, molecular characteristics, temperature and pressure on the slip velocity. In this paper the importance of these properties in extrusion are discussed.

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Viscometric flow under apparent wall slip in parallel-plate geometry

Journal of Non-Newtonian Fluid Mechanics ◽

10.1016/j.jnnfm.2004.06.013 ◽

2005 ◽

Vol 126 (2-3) ◽

pp. 105-114 ◽

Cited By ~ 8

Author(s):

O. Wein

Keyword(s):

Parallel Plate ◽

Wall Slip ◽

Viscometric Flow ◽

Apparent Wall Slip ◽

Plate Geometry

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Effects of the Types and Addition Amounts of Sludge on the True Rheological Properties of Petroleum Coke Slurry Flowing in Pipelines

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2014-0130 ◽

2015 ◽

Vol 13 (3) ◽

pp. 311-322 ◽

Cited By ~ 1

Author(s):

Meng Liu ◽

Yufeng Duan ◽

Xiuyuan Ma

Keyword(s):

Shear Rate ◽

Rheological Properties ◽

Petroleum Coke ◽

Slip Velocity ◽

Wall Slip ◽

Paper Mill ◽

Shear Thinning ◽

Tikhonov Regularization Method ◽

Plastic Fluid ◽

Dilatant Fluid

AbstractEffects of the types and addition amounts of sludge on the true rheological properties of petroleum coke water/sludge slurry (PCWS/PCSS) flowing in pipelines were investigated using the Tikhonov regularization method. Results show that PCWS of 59.8 wt% changes from pseudo-plastic fluid to dilatant fluid as the shear rate increases. However, PCWS of 63.4 wt% is a very complex fluid: shear thinning at low shear rate, followed by shear thickening over a critical shear rate, and a subsequent shear thinning at high shear rate. Rheological properties of PCWS have a significant change after the sludge was added. PCSS changes from dilatant fluid to pseudo-plastic fluid when the addition amounts of sewage sludge ascend to 10 wt%. Petroleum coke particles are trapped by the stable “network” structures, which are formed by flocculent sludge particles. The wall slip velocity of PCSS is higher than that of PCWS with the sludge amount increases, which is beneficial for pipe transportation. In addition, the wall slip velocity of PCSS containing sewage or petrochemical sludge increases with the wall shear rate increases, but the slip velocity of PCSS containing paper mill sludge first increases and then decreases.

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Deemulsification of Water-in-Oil Emulsion with Sludges

Water Quality Research Journal ◽

10.2166/wqrj.1987.034 ◽

1987 ◽

Vol 22 (3) ◽

pp. 437-443 ◽

Cited By ~ 5

Author(s):

N. Kosaric ◽

Z. Duvnjak

Keyword(s):

Activated Sludge ◽

Room Temperature ◽

Petroleum Refinery ◽

Treatment Plant ◽

Granular Sludge ◽

Activated Sludge Process ◽

Sludge Treatment ◽

Oil Emulsion ◽

Water In Oil Emulsion ◽

Aerobic Sludge

Abstract Aerobic sludge from a municipal activated sludge treatment plant, sludge from a conventional municipal anaerobic digester, aerobic sludge from an activated sludge process of a petroleum refinery, and granular sludge from an upflow sludge blanket reactor (USBR) were tested in the deemulsification of a water-in-oil emulsion. All sludges except the last one, showed a good deemulsification capability and could he used for a partial deemulsification of such emulsions. The rate and degree of the deemulsifications increased with an increase in sludge concentrations. The deemulsifications were faster at 85°C and required smaller amounts of sludge than in the case of the deemulsifications at room temperature. An extended stirring (up to a certain limit) in the course of the dispersion of sludge emulsion helped the deemulsification. Too vigorous agitation had an adverse effect. The deemulsification effect of sludge became less visible with an increase in the dilution of emulsion which caused an increase in its spontaneous deemulsification.

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Destruction of water-in-oil emulsions in electromagnetic fields in a dynamic mode

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2012.1.021 ◽

2012 ◽

Vol 9 (1) ◽

pp. 110-115

Author(s):

L.A. Kovaleva ◽

R.R. Zinnatullin ◽

V.N. Blagochinnov ◽

A.A. Musin ◽

Yu.I. Fatkhullina ◽

...

Keyword(s):

Dielectric Properties ◽

Radio Frequency ◽

Electromagnetic Fields ◽

Dynamic Mode ◽

Droplet Dynamics ◽

Oil Emulsion ◽

Numerical Studies ◽

Em Field ◽

Oil Emulsions ◽

Water In Oil Emulsion

Some results of experimental and numerical studies of the influence of radio-frequency (RF) and microwave (MW) electromagnetic (EM) fields on water-in-oil emulsions are presented. A detailed investigation of the dependence of the dielectric properties of emulsions on the frequency of the field makes it possible to establish the most effective frequency range of the EM influence. The results of water-in-oil emulsion stability in the RF EM field depending on their dielectric properties are presented. The effect of the MW EM field on the emulsion in a dynamic mode has been studied experimentally. In an attempt to understand the mechanism of emulsion destruction the mathematical model for a single emulsion droplet dynamics in radio-frequency (RF) and microwave (MW) electromagnetic fields is formulated.

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Selective and ultrafast agglomeration of chalcopyrite by a water in oil emulsion binder

Minerals Engineering ◽

10.1016/j.mineng.2021.106900 ◽

2021 ◽

Vol 167 ◽

pp. 106900

Author(s):

G. Sahasrabudhe ◽

G. DeIuliis ◽

J. Davy ◽

K.P. Galvin

Keyword(s):

Oil Emulsion ◽

Water In Oil Emulsion

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Quantification of shear viscosity and wall slip velocity of highly concentrated suspensions with non-Newtonian matrices in pressure driven flows

Rheologica Acta ◽

10.1007/s00397-021-01281-5 ◽

2021 ◽

Author(s):

Patrick Wilms ◽

Jan Wieringa ◽

Theo Blijdenstein ◽

Kees van Malssen ◽

Reinhard Kohlus

Keyword(s):

Shear Stress ◽

Liquid Phase ◽

Shear Rate ◽

Shear Viscosity ◽

Slip Velocity ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Wall Slip ◽

Flow Index ◽

Concentrated Suspensions

AbstractThe rheological characterization of concentrated suspensions is complicated by the heterogeneous nature of their flow. In this contribution, the shear viscosity and wall slip velocity are quantified for highly concentrated suspensions (solid volume fractions of 0.55–0.60, D4,3 ~ 5 µm). The shear viscosity was determined using a high-pressure capillary rheometer equipped with a 3D-printed die that has a grooved surface of the internal flow channel. The wall slip velocity was then calculated from the difference between the apparent shear rates through a rough and smooth die, at identical wall shear stress. The influence of liquid phase rheology on the wall slip velocity was investigated by using different thickeners, resulting in different degrees of shear rate dependency, i.e. the flow indices varied between 0.20 and 1.00. The wall slip velocity scaled with the flow index of the liquid phase at a solid volume fraction of 0.60 and showed increasingly large deviations with decreasing solid volume fraction. It is hypothesized that these deviations are related to shear-induced migration of solids and macromolecules due to the large shear stress and shear rate gradients.

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