3-Dimensional Flow Modeling of a Proposed Hanford Waste Treatment Plant Ion-Exchange Column Design

Aleman, Sebastian

Savannah River Site (S.C.)

关键词: Heat Transfer;    Hanford River Protection Project;    Efficiency;    Bubbles;    Waste Processing;   

DOI  :  10.2172/828469
RP-ID  :  WSRC-TR-2002-00309
RP-ID  :  AC09-96SR18500
RP-ID  :  828469

美国|英语

来源: UNT Digital Library

【 摘 要 】

Historically, it has been assumed that the inlet and outlet low activity waste plenums would be designed such that a nearly uniform velocity profile would be maintained at every axial cross-section (i.e., providing nearly 100 percent use of the resin bed). With this proposed design, we see a LAW outlet distributor that results in significant non-axial velocity gradients in the bottom regions of the bed with the potential to reduce the effectiveness'' of the overall resin bed. The magnitude of this efficiency reduction depends upon how far up-gradient of the LAW outlet these non-axial velocities persist and to what extent a ''dead-zone'' is established beneath the LAW outlet. This can impact loading and elution performance of the ion-exchange facility. Currently, no experimental studies are planned. The primary objective of this work was, through modeling, to assess the fluid dynamic impact on ''effective'' resin volume of the full-scale column based on its normal operation using a recently proposed LAW outlet distributor. The analysis effort was limited to 3-D flow only analyses (i.e., no follow on transport analyses) with 3-D particle tracking to approximate the impact that a nonaxial velocity profile would have on bed ''effectiveness''. Additional analyses were performed to estimate under nominal operating conditions the thermal temperature rise across a loaded resin bed and within its particles. Hydrogen bubble formation is not considered in the heat transfer analysis or in the determination of minimum flowrate. All modeling objectives were met.