Engineering topics

Devine, Nathan P.

Publications and source records attributed to Devine, Nathan P..

3 records

DOE OSTI2024

A Review and Revalidation of Equivalency Factors in H-Canyon

In recent years, an effort has begun to validate and reaffirm long-existing limits and equivalency factors in use at the H-Canyon (HCA) facility located at the Savanah River Site. Equivalency factors (EF) are coefficients used to express the reactivity of a quantity of a given isotope in terms of an equivalent amount of another isotope’s reactivity, commonly termed Fissile Gram Equivalent (FGE). For criticality safety purposes, EFs are often used to conservatively determine if a given mixed-isotope system is within previously established limits. These EFs are calculated by taking ratios of established subcritical limits for a given system or process.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2024

Zirconium Sludge Criticality Calculations in Large Process Tanks

The Savannah River Site’s H-Canyon facility has been tasked with accelerating the disposition of used research reactor fuels. • Future missions will involve dissolution of “Non-Aluminum” clad fuels – not easily dissolved – Nitric acid is not capable of dissolving stainless steel, Zirconium, and Hastelloy, clad fuels by itself • The electrolytic dissolver has been (re) selected as a disposition path for these fuels. 2

Devine, Nathan P.↗

DOE OSTI2024

Zirconium Sludge Criticality Calculations in Large Process Tanks

The Savannah River Site’s (SRS) H-Canyon recently re-activated its 6.3D electrolytic dissolver to dissolve stainless steel clad research reactor fuels from Japan. A potential new mission was identified to dissolve other long-cooled fuel stored at SRS that is not aluminum clad. In the basic process of dissolution, the spent fuel dissolves into nitric acid (bulk solution). The eight ft. high and four ft. radius 6.3D dissolver is unique in that it has a platinum-coated niobium insert to resist corrosion, and the niobium basket forms an anode and cathode arrangement within the charge chute (Fig 1,2). DC current flows from anode to cathode, at up to 10,000 amps at 45 volts, through the potential gradient in the nitric acid solution, which allows the stainless steel (or other non-aluminum cladding) of the fuel to dissolve.

Wade, Brindley↗