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Poirier, Michael R.

Publications and source records attributed to Poirier, Michael R..

Methods of separating materials by use of a centrifugal contactor

Centrifugal contactors that can be used for mixing or separating materials are described. The contactors include a sensing system including a communications fiber within the shaft of the contactors and access ports providing access from the communications fiber to the mixing/separating zone of the contactor. The sensing system can be utilized during operation of the contactor and can provide for detailed and accurate on-line characterization of a protocol, as well as process control and system modification as necessary during operation.

Restivo, Michael L.↗

M-Star ® Software Test and Verification

Savannah River Mission Completion (SRMC) currently manages the risk for retained hydrogen in the Defense Waste Processing Facility (DWPF) vessels by implementing a Retained Hydrogen Program. The current program relies on Sludge Batch (SB) 8 Gas Chromatograph data and on conservative assumptions concerning gas release and retention to determine allowable vessel Quiescent time (Q-time). The authors identified M-Star ® CFD as a software that could simulate processes such as fluid flow, heat transfer, species transport, chemical reactions, particle transport, and retained hydrogen gas release. Preliminary simulation results suggest that more realistic assumptions on gas retention and release may be feasible for the DWPF retained hydrogen program. Because of the desire to use the M-Star ® software to perform analyses that support nuclear safety, SRMC has requested Savannah River National Laboratory (SRNL) to upgrade the software classification level of M-Star ® CFD from level D to level A to perform analyses that support nuclear safety.

08 HYDROGEN↗

Mixing Study for the Modification of H-Canyon Tank 31 and 32 Recirculation Lines Via M-Star®

As a part of the Accelerated Basin De-Inventory (ABD) program Tanks 31 or 32 will be re-purposed to support increasing the number of annual Material Test Reactor (MTR) and High Flux Isotope Reactor (HFIR) dissolutions. The proposed plan will allow Tanks 31 or 32 to be used as the dissolver cold chemical solution makeup tank and storage tank. The dissolver cold chemicals are 50% nitric acid, process water, mercuric nitrate, and gadolinium nitrate. Tanks 31 and 32 are 9 ft. (outer diameter) x 36 ft, horizontal, and can hold approximately 56,000 liters (15,000 gallons) each. One full volume of Tanks 31 or 32 can support 4 HFIR 6.4D equivalent batches. Both tanks are equipped with liquid level instrumentation. Tank 31 is equipped with 1 pump used for transfer and recirculation while Tank 32 is equipped with two pumps, one for transfer and the other for recirculation. Each of the pumps is equipped with sample taps. The tanks do not have specific gravity instrumentation, an agitator, or a sampler. Piping modifications will also be performed to supply the tank with cold chemicals. The current dissolver chemical composition is 5.0 -8.5M HNO3 and ~0.2 g Gd/L. The recirculating pump connected to Tank 31 is rated for a flowrate 175 gpm while the pump connected to Tank 32 is rated for a flowrate 50 gpm.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Centrifugal contactor including central dynamic examination device

Centrifugal contactors that can be used for mixing or separating materials are described. The contactors include a sensing system including a communications fiber within the shaft of the contactors and access ports providing access from the communications fiber to the mixing/separating zone of the contactor. The sensing system can be utilized during operation of the contactor and can provide for detailed and accurate on-line characterization of a protocol, as well as process control and system modification as necessary during operation.

Restivo, Michael L.↗