PNNL-13501 - Pacific Northwest National Laboratory

Instrumented Test Loop for Evaluation of In Situ Real-Time Physical and Rheological Properties
Judith A. Bamberger, James A. Fort, Margaret S. Greenwood, Leonard J. Bond, Richard A. Pappas
Study Control Number: PN00059/1466
Many processes, including radioactive waste transfer operations, and several industrial processes, require real-time
instrumentation to measure physical, rheological, and constituent properties of slurries and multiphase flows to quantify
the state of mixing and solids concentration and particle size distribution, detect solids settling and stratification, and to
identify changes in rheology and phase by measuring colloid agglomeration and gelation. Previous experience at the
Hanford Site has provided ample evidence of the adverse effects that result from pipeline plugging. To support ultrasonic
instrument development and deployment, two flow testing systems, one operating in the laminar flow regime and one
operating over a higher flow rate range, were developed. These flow “loops” provide a flexible test system equipped with
a suite of unique nonintrusive ultrasonic sensing systems to characterize slurry physical and rheological properties in situ
in real time in pipelines and vessels under prototypic operating conditions.
Project Description
The purpose of this project was to increase our capability
for evaluating fluid and slurry physical and rheological
properties in situ, in real-time over a broad range of
simulated Hanford Site and industrial process conditions.
These testing systems require only small quantities of
fluids, slurries, or suspensions to operate while evaluating
fluid properties using ultrasonic instruments that are being
developed to characterize physical and rheological
properties. The instruments used included sensors to
measure flow velocity and rheological profiles, density,
viscosity, solids concentration, particle size, speed of
sound through the mixture, and the ability to detect
interfaces. The loops are co-located with the Food
Science and Process Measurement Laboratory to provide
access to complementary fluid mixing and
characterization equipment. To provide flexibility to
evaluate a range of sensors, the loops include penetrations
for spool pieces housing the unique instrumentation. This
capability permits analysis and evaluation of the physical
and rheological properties of fluids, slurries, and colloidal
suspensions under flowing conditions that are similar to
those obtained during transport during production. The
lamina flow loop and equipment were successfully used
to evaluate instrument capability to characterize thick
paste-like slurries and viscous fluids. They can also
operate using simulants to model radioactive waste
slurries and typical intermediate process stages
encountered during food production.
Introduction
Many industrial processes in the oil and gas, chemical,
food, forest product, and mineral processing industries
could benefit from real-time quantification of physical,
424 FY 2000 Laboratory Directed Research and Development Annual Report
rheological, and constituent properties. This need is also
prevalent at the DOE Hanford Site and other DOE sites
where radioactive waste transport characterization needs
include quantifying the state of mixing, solids
concentration and particle size distribution, detection of
settling and stratification, and identifying changes in
rheology and phase through colloid agglomeration and
gelation. Previous experience at the Hanford Site has
provided ample evidence of the adverse effects that result
from pipeline plugging. In general, two groups of
particulate commonly exist within the Hanford tanks as
well as in the petrochemical industries. These are
insoluble solids that are subject to settling, saltation and
bed formation, and soluble species that in addition to
settling, could lead to precipitation on the walls (scaling
or fouling) and bulk precipitation which could form plugs
due to compaction. The pulp and paper industry faces
challenges similar to those at Hanford. Pulp fibers tend to
flocculate into clumps as they are processed in the
headbox. These clumps deposit on the wire used to form
the paper sheet resulting in poor paper formation. The
pulp and paper industry also implements dilution to
reduce flocculation. Our Laboratory developed ultrasonic
sensors that can be used to nonintrusively characterize
physical and rheological properties of these processes.
Several large flow loops at our Laboratory require
significant (190 to 568 L [50 to 150 gal]) quantities of
simulant. To support rapid evaluation of sensor
applicability to support DOE and Hanford Site
characterization needs, a reduced-volume system was
developed to evaluate the feasibility of ultrasonic
characterization of the physical and rheological properties
of unique process streams.