skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Characterization of Filtration Scale-Up Performance

Technical Report ·
DOI:https://doi.org/10.2172/962841· OSTI ID:962841

The scale-up performance of sintered stainless steel crossflow filter elements planned for use at the Pretreatment Engineering Platform (PEP) and at the Waste Treatment and Immobilization Plant (WTP) were characterized in partial fulfillment (see Table S.1) of the requirements of Test Plan TP RPP WTP 509. This test report details the results of experimental activities related only to filter scale-up characterization. These tests were performed under the Simulant Testing Program supporting Phase 1 of the demonstration of the pretreatment leaching processes at PEP. Pacific Northwest National Laboratory (PNNL) conducted the tests discussed herein for Bechtel National, Inc. (BNI) to address the data needs of Test Specification 24590-WTP-TSP-RT-07-004. Scale-up characterization tests employ high-level waste (HLW) simulants developed under the Test Plan TP-RPP-WTP-469. The experimental activities outlined in TP-RPP-WTP-509 examined specific processes from two broad areas of simulant behavior: 1) leaching performance of the boehmite simulant as a function of suspending phase chemistry and 2) filtration performance of the blended simulant with respect to filter scale-up and fouling. With regard to leaching behavior, the effect of anions on the kinetics of boehmite leaching was examined. Two experiments were conducted: 1) one examined the effect of the aluminate anion on the rate of boehmite dissolution and 2) another determined the effect of secondary anions typical of Hanford tank wastes on the rate of boehmite dissolution. Both experiments provide insight into how compositional variations in the suspending phase impact the effectiveness of the leaching processes. In addition, the aluminate anion studies provide information on the consequences of gibbsite in waste. The latter derives from the expected fast dissolution of gibbsite relative to boehmite. This test report concerns only results of the filtration performance with respect to scale-up. Test results for boehmite dissolution kinetics and filter fouling are reported elsewhere (see Table S.1). The primary goal of scale-up testing was to examine how filter length influenced permeate flux rates. To accomplish this, the existing cells unit filter system, which employs a 2-ft-long, 0.5-in. (inner) diameter sintered stainless steel filter element, was redesigned to accommodate an 8-ft. sintered stainless steel filter element of the same diameter. Testing was then performed to evaluate the filtration performance of waste simulant slurries. Scale-up testing consisted of two separate series of filtration tests: 1) scale-up axial velocity (AV)/transmembrane pressure (TMP) matrix tests and 2) scale-up temperature tests. The AV/TMP matrix tests examined filtration performance of two different waste simulant slurries in the 8-ft. cells unit filter system. Waste simulant slurry formulations for the 8-ft. scale-up test was selected to match simulant slurries for which filtration performance had been characterized on the 2-ft CUF. For the scale-up temperature tests, the filtration performance at three test temperatures (i.e., 25°C, 40°C, and 60°C) was determined to evaluate if filter flux versus temperature correlations developed using the 2-ft filters were also valid for the 8-ft filters.

Research Organization:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
962841
Report Number(s):
PNNL-18117; 830403000; TRN: US200917%%120
Country of Publication:
United States
Language:
English