Ion Exchange Modeling Of Cesium Removal From Hanford Waste Using Spherical Resorcinol-Formaldehyde Resin

Aleman, S.E.; Hamm, L.; Smith, Frank

doi:10.2172/1235438

Cited by 9 publications

(13 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Modeling ion-exchange columns for cesium removal from radioactive liquid wastes was presented in previous ion-exchange studies at SRNL (12)(13)(14)(15). The following sections discuss the key methodologies used to model ion-exchange column behavior.…”

Section: Ion-exchange Modelingmentioning

confidence: 99%

“…Based on available batch equilibrium studies, the relative affinities for adsorption have been computed to be Cs+ > Rb+ > K+ > Na+ for RF (13) and Cs+ >> K+ > Na+ for SL644 (12). Given this information, early column performance (i.e., the first 5 to 10 bed volumes) generally requires the use of the multi-component formulations.…”

Section: Ion-exchange Modelingmentioning

confidence: 99%

“…Tortuosity factors for SL644 and sRF resin have been determined (12,13) by analyzing experimental data obtained. It was found that using τ = 3 gave reasonable results.…”

Section: Pore Diffusionmentioning

confidence: 99%

“…Modeling studies have been conducted for both SL644 and sRF resins on radioactive alkaline wastes stored at the Hanford Site and the SRS (12)(13)(14). One significant difference between those wastes is the concentration of potassium.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Modeling Ion-Exchange Processing with Spherical Resins for Cesium Removal

Hang

Nash

Aleman

2013

Separation Science and Technology

View full text Add to dashboard Cite

Abstract:The spherical Resorcinol-Formaldehyde and hypothetical spherical SuperLig ® 644ion-exchange resins are evaluated for cesium removal from radioactive waste solutions.Modeling results show that spherical SuperLig® 644 reduces column cycling by 50% for highpotassium solutions. Spherical Resorcinol Formaldehyde performs equally well for the lowestpotassium wastes. Less cycling reduces nitric acid usage during resin elution and sodium addition during resin regeneration, therefore, significantly decreasing life-cycle operational costs.A model assessment of the mechanism behind "cesium bleed" is also conducted. When a resin bed is eluted, a relatively small amount of cesium remains within resin particles. Cesium can bleed into otherwise decontaminated product in the next loading cycle. The bleed mechanism is shown to be fully isotherm-controlled vs. mass transfer controlled. Knowledge of residual postelution cesium level and resin isotherm can be utilized to predict rate of cesium bleed in a mostly non-loaded column. Overall, this work demonstrates the versatility o f the ion-exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. This evaluation justifies further development of a spherical form of the SL644 resin.

show abstract

Section: Ion-exchange Modelingmentioning

confidence: 99%

Section: Ion-exchange Modelingmentioning

confidence: 99%

“…Tortuosity factors for SL644 and sRF resin have been determined (12,13) by analyzing experimental data obtained. It was found that using τ = 3 gave reasonable results.…”

Section: Pore Diffusionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Modeling Ion-Exchange Processing with Spherical Resins for Cesium Removal

Hang

Nash

Aleman

2013

Separation Science and Technology

View full text Add to dashboard Cite

show abstract

“…Bucket average lag column cesium breakthrough profiles were calculated by spreadsheet based on the cumulative cesium breakthrough and the solution volume processed. Detailed descriptions of the methodology used were reported by Aleman and Hamm [17,18].…”

Section: Modelingmentioning

confidence: 99%

Comparisons of Crystalline Silicotitanate and Resorcinol Formaldehyde Media for Cesium Removal by In-tank Column Processing

Smith

Lee

King

et al. 2008

Separation Science and Technology

View full text Add to dashboard Cite

Chemical and thermal performance of crystalline silicotitanate (CST) and resorcinolformaldehyde (RF) ion exchange media were predicted for column configurations designed for installation in high level waste tanks and intended for cesium removal from radioactive waste supernates. Modeling predictions for the processing of a known Savannah River Site tank waste composition were generated. In a two column configuration under presumed nominal operating conditions (432 gallon packed bed, 10 gpm liquid flow, 25 ºC, 45 nCi/g average breakthrough limit) with lead/lag column rotation between processing cycles, approximately two cycles were predicted to treat 1,000,000 gallons of radioactive waste with CST as compared to three cycles predicted for RF. However, this processing mode was shown to be highly unfavorable for RF due to the fact that the lead column is unnecessarily exposed to large radiation doses during movement of the cesium mass transfer zone into the lag column. Thermal modeling calculations indicated that maximum temperatures within stagnant, packed CST and RF columns containing the highest anticipated cesium loading and no active cooling will reach 128 and 78 ºC, respectively, within 6 days. Active cooling maintains the cesiumsaturated CST and RF columns below 88 and 41 ºC, respectively, under stagnant flow conditions.

show abstract