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Savannah River National Laboratory (SRNL) performed pilot-scale hydraulic/chemical testing of spherical resorcinol formaldehyde (RF) ion exchange (IX) resin for the River Protection Project-Hanford Tank Waste Treatment & Immobilization Plant (WTP) Project. The RF resin hydraulic cycle testing was conducted in two pilot-scale IX columns, 1/4 and 1/2 scale. A total of twenty-three hydraulic/chemical cycles were successfully completed on the spherical RF resin. Sixteen of these cycles were completed in the 24″ IX Column (1/2 scale column). Hydraulic testing showed that the permeability of the RF resin remained essentially constant, with no observed trend in the reduction of the permeability as the number of cycles increased. The permeability during the pilot-scale testing was 3 times better than the design requirements of the WTP full-scale IX system. The RF resin bed showed no tendency to form fissures or pack more densely as the number of cycles increased. Particle size measurements of the RF resin showed no indication of particle size change (for a given chemical) with cycles and essentially no fines formation. The permeability of the resin bed was uniform with respect to changes in bed depth. Upflow Regeneration and Simulant Introduction in the IX columns revealed another RF resin benefit; negligible radial pressures to the column walls from the swelling of resin beads. The hydraulic and chemical performance of the spherical RF resin during cycle testing was found to be superior to all other tested IX resins. The pilot-scale testing indicates that the RF resin is durable and should hold up to many hydraulic cycles in actual radioactive Cesium (Cs) separation.

DISCLAIMERThis report was prepared as an account of work sponsoredby an agency of the UnitedStates Government.Neither the United States Governmentnor any agency thereof,nor any of their employees, makes any warranty, express or impliecl or assumes any legal liability or respondility for the accuracy, completeness,or usefulnessof any information apparatus, product, or process disclosed,or representsthat its use would not infringeprivately owned rights.Referencehereinto any specificcommeraal product, process,or serviceby trade name, trademark manufacturer,or otherwisedoesnot necessarilyconstituteor implyits endorsement, recommendation,or favoring by the United States Governmentor any agency thereof. The views and opinionsof authorsexpressedhereindonot necessarilystate or reflectthose of the UnitedStatesGovernmentor any agencythereof. The SRS high level waste (HLW) tank ventilationsystems are equippedwith conventionaldisposableglass-fiberHEPA filter. Routineremoval, replacement, and disposalof these filtersare not only costly, but subjectssite personnel to radiationexposure and contributeto an ever-growing waste disposalproblem for the site.The Engineering Development Section designed and constructed a test rig, as shown in Drawing A (pictures in Appendix B) to simulate the conditions found in a HLW tank ventilation system. Two sintered metal filters were tested, one manufactured by Mott Filter Corporation and the other by the Pall Filter Corporation. Testing was conducted to determine the feasibility of washing HEPA filters in situ after becoming plugged with the simulated solutions found in the HLW tanks.The filters were tested using simulated HLW salt, simulated HLW sludge and South Carolina road dust to simulate atmospheric dust. The filters were operated until they became plugged (airflow decreases 20% or greater due to particulate matter buildup from the simulated solutions). The filters were then cleaned in situ by spraying off the soiled side of the filters with 10°/0nitric acid and/or 10°/0sodium hydroxide and/or water. After the wash cycle, the filters were returned to service.During the simulated HLW salt test, the Pall filter completely plugged after being saturated with water during the in situ wash, as shown in Figure 1, 2 and 3. Since the PalI filter did not recover from the in situ cleaning without oven drying, it was not suitable for our use and removed from fhrther testing. On the other hand, the Mott filter was insensitive to water and recovered to approximately the original airflow and differential pressure (dP) after the in situ cleaning, as shown in Figures 1,4 and 5. Distilled or nano-pure water was the only solution required to clean the Mott filter during the salt test.The Mott filter recovered after in situ cleaning after pluggage with dry salt. As shown in Figures 6 and 7, the airflow and dP across the filter recovered after each cleaning cycle. The Mott filter was also regenerable with in situ cleaning while testing with both simulated HL W sludge and South Carolina road dust. Figures 10...

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