Demonstration and Optimization of BNFL's Pulsed Jet Mixing and RFD Sampling Systems Using NCAW Simulant

Bontha,; Golcar, G.R.; Hannigan, N

doi:10.2172/761039

Cited by 6 publications

(6 citation statements)

References 2 publications

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“…Additionally, PNNL staff have conducted significant experimental and analytical studies investigating PJM performance for mixing non-Newtonian slurries (Bamberger et al 2005;Johnson et al 2005;Meyer et al 2005Meyer et al , 2006Kurath et al 2007;Meyer and Etchells 2007;Bamberger et al 2008) and conducted tests with neutralized current acid waste simulant (Bontha et al 2000). The work with non-Newtonian slurries was expanded to determine the technical basis for scaling air sparging systems for mixing nonNewtonian slurries Guerrero and Restivo 2004).…”

Section: Pnnl Pulse Jet Mixer Studiesmentioning

confidence: 99%

The Role of Cohesive Particle Interactions on Solids Uniformity and Mobilization During Jet Mixing: Testing Recommendations

Gauglitz¹,

Wells²,

Bamberger³

et al. 2010

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Executive SummaryRadioactive waste that is currently stored in large underground tanks at the Hanford Site will be staged in selected double-shell tanks (DSTs) and then transferred to the Waste Treatment and Immobilization Plant (WTP). Before being transferred, the waste will be mixed, sampled, and characterized to determine if the waste composition meets the waste feed specifications. Washington River Protection Solutions (WRPS) is conducting a Tank Mixing and Sampling Demonstration Program to determine the mixing effectiveness of the current baseline mixing system that uses two jet mixer pumps to mobilize and mix waste in DSTs and to determine the adequacy of the planned sampling method. The overall purpose of the demonstration program is to mitigate the technical risk associated with the mixing and sampling systems meeting the feed certification requirements for transferring waste to the WTP.A critical aspect of meeting the feed certification requirements is ensuring that the collected samples will adequately represent the contents of the tank and that all batches of transferred waste are sufficiently uniform so that they all are equivalent to the characterized samples. However, the tank waste contains slurries of solid particles that settle and may become progressively more concentrated towards the bottom of the tank. Obtaining a perfectly uniform distribution of waste in the DSTs with a mixing system may not be possible. To determine how close this ideal can be approached, the expected performance of the DST mixing and sampling systems must be quantified. There have been a number of laboratory studies and full-scale tank farm studies that evaluated mixing behavior; these studies are discussed later in this report. However, these studies do not provide adequate quantitative information to evaluate the performance of the planned sampling and the batch uniformity. Accordingly, WRPS' demonstration program is focusing specifically on quantifying the uniformity of samples and batch transferred material to reduce the technical risk associated with these systems.The first phase of the demonstration program is to conduct scaled tests that appropriately match fullscale behavior and to evaluate sampling methodologies and the uniformity of batch transfers. The initial scaled testing will use non-cohesive particles where the particles do not have cohesive interactions that would cause the particles to stick together. The purpose of this report is to analyze existing data and evaluate whether scaled mixing tests with cohesive simulants are needed to meet the overall objectives of the small-scale mixing demonstration program. This evaluation will focus on estimating the role of cohesive particle interactions on various physical phenomena that occur in parts of the mixing process. A specific focus of the evaluation will be on the uniformity of suspended solids in the mixed region.The evaluation shows that cohesive particle interaction will have multiple effects through a number of different mechanisms. Some of the effects ...

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Section: Pnnl Pulse Jet Mixer Studiesmentioning

confidence: 99%

The Role of Cohesive Particle Interactions on Solids Uniformity and Mobilization During Jet Mixing: Testing Recommendations

Gauglitz¹,

Wells²,

Bamberger³

et al. 2010

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“…Many of the studies focused on quantifying mixing behavior and performance (Bontha et al 2000(Bontha et al , 2003a(Bontha et al , 2003bEnderlin et al 2003;Johnson et al 2003;Bates et al 2003;Bamberger et al 2005;Meyer et al 2005;Johnson et al 2005;Poloski et al 2005;Bontha et al 2007;, and other studies focused on gas retention and release, but also provided improved understanding of PJM mixing performance (Stewart et al , 2006a(Stewart et al , 2006band Russell et al 2005). These previous PJM studies were conducted with non-Newtonian simulants that did not settle, but they still provided a significant basis for understanding and estimating the performance of PJMs for mobilizing settling layers of cohesive materials.…”

Section: Pjm Mixing Of Cohesive Layersmentioning

confidence: 99%

“…These previous PJM studies were conducted with non-Newtonian simulants that did not settle, but they still provided a significant basis for understanding and estimating the performance of PJMs for mobilizing settling layers of cohesive materials. These previous studies were conducted in vessels that were filled with simulants that had uniform non-Newtonian fluid properties throughout the vessel, with the exception of the study by Bontha et al (2000) that used a chemical simulant of AZ-101 that settled.…”

Section: Pjm Mixing Of Cohesive Layersmentioning

confidence: 99%

“…These studies did not consider waste materials where the materials in the tank could segregate into a settled layer with non-Newtonian properties below a liquid layer with Newtonian properties. Numerous other studies have investigated PJM mixing performance, but with the exception of the earliest study by Bontha et al (2000), these studies also focused on vessels filled with non-Newtonian slurries that did not settle (Bontha et al 2000(Bontha et al , 2003a(Bontha et al , 2003bEnderlin et al 2003;Johnson et al 2003;Bates et al 2003;Bamberger et al 2005;Meyer et al 2005;Johnson et al 2005;Poloski et al 2005;Bontha et al 2007;). Accordingly, additional understanding is needed for PJM mobilization of settled cohesive layers, including the role of important parameters, such as the shear strength and height of the settled layers, to allow the quantitative prediction of the gas retention and release from these layers.…”

Section: Introductionmentioning

confidence: 99%

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An Approach to Understanding Cohesive Slurry Settling, Mobilization, and Hydrogen Gas Retention in Pulsed Jet Mixed Vessels

Gauglitz¹,

Wells²,

Fort³

et al. 2009

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“…( a ) Behavior noted in laboratory record book for Bontha et al (2000). Following mixing, the test (nominally 10-foot simulant depth in a 12.75-foot-diameter vessel, approximately 18 wt% total solids loading) was left in a shut-down condition and unattended for approximately 4 to 5 days.…”

Section: Noted This Inconsistency By Statingmentioning

confidence: 99%

Hanford Sludge Simulant Selection for Soil Mechanics Property Measurement

Wells¹,

Russell²,

Mahoney³

et al. 2010

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SummaryThis report describes current work to select or develop two chemical sludge simulants for testing relative to problems of hydrogen gas retention and release encountered in the double shell tanks at the Hanford Site near Richland, Washington. Wastes from single shell tanks are being transferred to double shell tanks for safety reasons (some single shell tanks are leaking or are in danger of leaking), but the available double-shell tank space is limited.The current System Plan for the Hanford Tank Farms (Rev. 4, Certa and Wells 2009) uses relaxed buoyant displacement gas release event (BDGRE) controls for deep sludge (i.e., high level waste [HLW]) tanks, which allows the tank farms to use more storage space, i.e., increase the sediment depth, in some of the double-shell tanks (DSTs). The relaxed BDGRE controls are based on preliminary analysis of a gas release model from van Kessel and van Kesteren (2002). Application of the van Kessel and van Kesteren model requires parametric information for the sediment, including the lateral earth pressure at rest and shear modulus. No lateral earth pressure at rest and shear modulus in situ measurements for Hanford sludge are currently available.The two chemical sludge simulants will be used in follow-on work to experimentally measure the van Kessel and van Kesteren (2002) model parameters, lateral earth pressure at rest, and shear modulus. The simulants are selected via similarity to measured Hanford sludge chemical and physical properties, including liquid density, viscosity, and pH, undissolved particle size and density, and slurry rheology to maximize the likelihood that the simulants will have similar lateral earth pressure at rest and shear modulus as Hanford sludge. Simulant 1 is selected from those Hanford sludge simulants that have previously been produced and characterized, and Simulant 2 is developed based upon the chemistry of a specific retrieval SST scenario. In Section 2, pertinent Hanford sludge properties are summarized, Simulant 1 is selected, and the chemistry for Simulant 2 is developed and presented. Simulant production is described in Section 3, and simulant property measurements are presented in Section 4. A summary is provided in Section 5.

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Demonstration and Optimization of BNFL's Pulsed Jet Mixing and RFD Sampling Systems Using NCAW Simulant

Abstract: Portions of this document may be illegible in electronic image products. Images are produced from the best available original document.

Cited by 6 publications

References 2 publications

The Role of Cohesive Particle Interactions on Solids Uniformity and Mobilization During Jet Mixing: Testing Recommendations

The Role of Cohesive Particle Interactions on Solids Uniformity and Mobilization During Jet Mixing: Testing Recommendations

An Approach to Understanding Cohesive Slurry Settling, Mobilization, and Hydrogen Gas Retention in Pulsed Jet Mixed Vessels

Hanford Sludge Simulant Selection for Soil Mechanics Property Measurement

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