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in creator/contributor: "Rassat, S.D."  
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Bubble retention in synthetic sludge: Testing of alternative gas retention apparatus

Description: Several of the underground storage tanks currently used to store waste at Hanford have been placed on the Flammable Gas Watch List, because the waste is either known or suspected to generate, store, and episodically release flammable gases. The objective of this experimental study is to develop a method to measure gas bubble retention in simulated tank waste and in diluted simulant. The method and apparatus should (1) allow for reasonably rapid experiments, (2) minimize sample disturbance, and … more
Date: July 1, 1995
Creator: Rassat, S. D. & Gauglitz, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gas bubble retention and its effect on waste properties: Retention mechanisms, viscosity, and tensile and shear strengths

Description: Several of the underground nuclear storage tanks at Hanford have been placed on a flammable gas watch list, because the waste is either known or suspected to generate, store, and episodically release flammable gases. Because retention and episodic release of flammable gases from these tanks containing radioactive waste slurries are critical safety concerns, Pacific Northwest Laboratory (PNL) is studying physical mechanisms and waste properties that contribute to the episodic gas release from th… more
Date: August 1, 1995
Creator: Gauglitz, P. A.; Rassat, S. D. & Powell, M. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Buoyancy and Dissolution of the Floating Crust Layer in Tank 241-SY-101 During Transfer and Back-Dilution

Description: To remediate gas retention in the floating crust layer and the potential for buoyant displacement gas releases from below the crust, waste will be transferred out of Hanford Tank 241-SY-101 (SY-101) in the fall of 1999 and back-diluted with water in several steps of about 100,000 gallons each. To evaluate the effects of back-dilution on the crust a static buoyancy model is derived that predicts crust and liquid surface elevations as a function of mixing efficiency and volume of water added duri… more
Date: November 22, 1999
Creator: Stewart, C. W.; Sukamto, J. H.; Cuta, J. M. & Rassat, S. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Discussion of SY-101 Crust Gas Retention and Release Mechanisms

Description: The flammable gas hazard in Hanford waste tanks was made an issue by the behavior of double-shell Tank (DST) 241-SY-101 (SY-101). Shortly after SY-101 was filled in 1980, the waste level began rising periodically, due to the generation and retention of gases within the slurry, and then suddenly dropping as the gases were released. An intensive study of the tank's behavior revealed that these episodic releases posed a safety hazard because the released gas was flammable, and, in some cases, the … more
Date: February 23, 1999
Creator: Rassat, S. D.; Gauglitz, P. A.; Caley, S. M.; Mahoney, L. A. & Mendoza, D. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of gas bubble retention and release: results for Hanford Waste Tanks 241-S-102 and 241-SY-103 and single-shell tank simulants

Description: Research at Pacific Northwest National Laboratory (PNNL) has probed the physical mechanisms and waste properties that contribute to the retention and release of flammable gases from radioactive waste stored in underground tanks at Hanford. This study was conducted for Westinghouse Hanford Company as part of the PNNL Flammable Gas Project. The wastes contained in the tanks are mixes of radioactive and chemical products, and some of these wastes are known to generate mixtures of flammable gases, … more
Date: September 1, 1996
Creator: Gauglitz, P. A.; Rassat, S. D.; Bredt, P. R.; Konynenbelt, J. H.; Tingey, S. M. & Mendoza, D. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of gas retention and release: Experimental results for Hanford waste tanks 241-AW-101 and 241-AN-103

Description: The 177 storage tanks at Hanford contain a vast array of radioactive waste forms resulting, primarily, from nuclear materials processing. Through radiolytic, thermal, and other decomposition reactions of waste components, gaseous species including hydrogen, ammonia, and the oxidizer nitrous oxide are generated within the waste tanks. Many of these tanks are known to retain and periodically release quantities of these flammable gas mixtures. The primary focus of the Flammable Gas Project is the … more
Date: September 1, 1997
Creator: Rassat, S. D.; Gauglitz, P. A.; Bredt, P. R.; Mahoney, L. A.; Forbes, S. V. & Tingey, S. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of gas retention and release: Experimental results for Hanford single-shell waste tanks 241-A-101, 241-S-106, and 241-U-103

Description: The 177 underground waste storage tanks at the Hanford Site contain millions of gallons of radioactive waste resulting from the purification of nuclear materials and related processes. Through various mechanisms, flammable gas mixtures of hydrogen, ammonia, methane, and nitrous oxide are generated and retained in significant quantities within the waste in many ({approximately}25) of these tanks. The potential for large releases of retained gas from these wastes creates a flammability hazard. It… more
Date: September 1, 1998
Creator: Rassat, S. D.; Caley, S. M.; Bredt, P. R.; Gauglitz, P. A.; Rinehart, D. E. & Forbes, S. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dynamics of Crust Dissolution and Gas Release in Tank 241-SY-101

Description: Due primarily to an increase in floating crust layer thickness, the waste level in Hanford Tank 241-SY-101 (SY-101) has grown appreciably, and the flammable gas volume stored in the crust has become a potential hazard. To remediate gas retention in the crust and the potential for buoyant displacement gas releases from the nonconnective layer at the bottom of the tank, SY-101 will be diluted to dissolve a large fraction of the solids that allow the waste to retain gas. In this work we develop un… more
Date: January 26, 2000
Creator: Rassat, S. D.; Stewart, C. W.; Wells, B. E.; Kuhn, W. L.; Antoniak, Z. I.; Cuta, J. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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