On-line Process Rheometry Using Oscillatory Squeeze Flow XVIth International Congress on Rheology, Lisbon, August 2012 David Konigsberg1, T. M. Nicholson1, P. J. Halley 1 P. Koria2, E. Owen3, P. K. Bhattacharjee4 and T. J. Kealy4 1Department of Chemical Engineering, The University of Queensland, St. Lucia, QLD, Australia 2GlaxoSmithKline, Consumer Healthcare Technical, GSK House, TW8 9GS, UK 3GlaxoSmithKline, Consumer Healthcare R&D,Surrey, KT13 0DE, UK 4Rheology Solutions, OLR Group, Bacchus Marsh, Victoria, Australia

The OnLine Rheometer

• A process rheometer that delivers a flow curve characterising the viscoelastic behaviour of process fluids in real-time

•  In/On-line, Real-time measurements •  Accelerate decision making •  Reduce time associated with sampling and sample

handling processes

•  Distinguished from many online viscometers that provide a single point measurement

•  Plates separate and the sample is replenished

•  Top plate oscillates at predefined frequencies.

•  Bottom plate registers the force

•  Plates come within specified distance of each other

Installations

OLR

In-line Operation

OLR

On-line Operation

Further processing required

Ready for next processing step

PLC / Operator

Fields et al , JNNFM, 1996, 65, 177-194 Bell et al Rheol Acta. 2006;46(1):111-121.

Background Theory

p0= force amplitude; c = phase lag; (distance the plate moves) = h; = density of the fluid; a = radius of the top plate and * =

complex viscosity

•  Gap varies in the z-direction about the equilibrium distance of h with a frequency in time such that

•  Total normal force is given by

Limits??

a)  If the measured force is influenced because the plates are submerged

b)  Effect of geometry/fluid constitutive behaviour on the measurements

• Flow Solve® • Lagrangian finite element code • Developed by University of Leeds ( Bishko et al, JNNFM, 1999;82,255-273) •  Employs a Delauney mesh that is embedded in the fluid, such that the elements carry their strain history with them

•  Combines a finite element solution of the momentum and continuity equations with the constitutive equations

•  Produces a time dependent solution of the flow; which is assumed to start from rest

•  Program can account for mesh distortions by reconnecting points as required to preserve the Delauney triangulation

Test Geometries

A. Submerged (bounded) : Plates submerged and fluid bounded by the sensor walls

(A)

D. Semi-submerged : Unbounded fluid but top-plate not completely submerged

(D)

(B)

B. Submerged (unbounded) : Plates submerged in an infinite sea

(C)

C. Unsubmerged : Fluids confined between two endplates

(E)

( )

E. Submerged (confined) : Fluid confined within a small cavity and plates completely submerged

Results: Simulations

•  Fluid: commercial soap (Dettol ®)

•  Characterised using ARES (TA Instruments, USA) and response fitted to a Maxwell model

Secondary flow patterns develop

ndar

mm/s

Comparison With Experiments

8

15% 200K PS in DEP

Dettol® •  Simulations provide a handle on design of the sensor

•  Predicts experimental observations reasonably well

•  Experiments with OLR simulate On-line operation

•  High frequency data via time temperature superposition

Pilot Plant Experiments

Φ

•  OnLine Rheometer : Strain 0.75%, Swept (1-100Hz) Sine wave •  Laboratory Rheometer : HaakeMARS III ® (Thermo Fisher Scientific) •  In-line Viscometers : Proline Promass® (Endress & Hauser)

VA Series ® (Marimex) •  Test Material : 2.5% solution of carboxymethyl

cellulose (CMC) in water

1: OLR 2: Flowmeter 3: Measuring tank

4: Bulk tank 5: Mono pump 6: Online Viscometer

7: Inspection window 8: Pressure transducers 9: Valves

Results of experiments conducted at various flow-rates.

Results: OLR & Laboratory Rheometer

• Laboratory rheometer represented using cross symbols ( ) are linear viscoelastic response

• Other symbols represent measurements made by the OLR for repeated experiments at a fixed flow-rates

1500 kgs/hr 0.11m/s

1900 kgs/hr 0.14m/s

2900 kgs/hr 0.21m/s

Results: Pipe-loop & Process Viscometers

P in a flowing pipe

Marimex ViscoScope®

Laboratory rheometer E&H Proline

flowmeter

®

•  Laminar flow •  Use wall shear rate •  Use Metzner-Reed Reynolds number

(Metzner AB, Reed JC.. AIChE J. 1955,1,434-440.)

Results: Pipe-Loop & Process Viscometers

E&H Proline flowmeter

Laboratory rheometer

oratory

P in a flowing pipe

Marimex ViscoScope ®

•

•  OnLine Rheometer for in/on-line, real-time QA/QC

demonstrated

•  Design is based on rigorous mathematical analysis and simulations

•  Demonstrated success in producing viscoelastic measurements that agree quantitatively with Laboratory rheometers, on-line and in real-time under controlled conditions.

•  Offers superior finger-printing of complex fluids flowing in a pipe compared to prototypical on-line viscometers.

Conclusions

•  The OLR commercialisation project at Rheology Solutions is part-funded by the Australian Government Commercialisation Australia ESC Funding from Dept. Innovation, Industry & Science

•  PKB acknowledges library support through Department of Materials Engineering, Monash University, Clayton, Victoria

Acknowledgements