Jamaican Connection

Posted: May 7, 2014 - 5:52pm | Y-12 Report | Volume 10, Issue 2 | 2014

This nonproliferation project necessitated the creation of uranium dioxide powder, which can react vigorously with air — a safety and quality issue. To prevent that reaction, Y-12 researchers developed a new method of making the powder that proved highly successful.

When scientists in Jamaica needed to replace their research reactor’s highly enriched uranium fuel with a nonproliferable low-enriched-uranium substitute, Y‑12 stepped forward to help.

“Our role is to manage fabrication of low-enriched-uranium fuel pins for the reactor core and to produce the uranium dioxide feedstock,” said a manager in Y‑12’s Nuclear Nonproliferation and Global Security Programs. The new pins will replace those made of highly enriched uranium that fuel the Safe LOW-POwer Kritical Experiment reactor in Kingston, Jamaica.

Making the new fuel feedstock itself — low-enriched uranium dioxide powder — was a technical challenge requiring collaboration among Y‑12’s Production, Development, Quality and Program Management organizations. The project provided an opportunity to apply historical knowledge, revive a long-idled process and achieve a tight enrichment-range target.

The first step was to create the type of uranium trioxide powder required as feedstock to produce uranium dioxide. Production had a discontinued process that had generated desired material in the past. That process was reviewed and updated for use with the current equipment.

Testing after the first production batch revealed an enrichment level above the target range, indicating that residual highly enriched uranium in the process equipment had crept in. Depleted uranium was blended with the material to bring it into specification.

“It’s an honor to be part of this international nonproliferation effort and bring some of Y‑12’s former capabilities back to life,” said Kathy Martin, a processing manager. “It has been a challenging learning experience, reading old dusty reports and notes, but some things are learned only by doing.” Through several steps, Development reduced the uranium trioxide feedstock to uranium dioxide by applying a process the organization had recently developed. Uranium dioxide powder can react vigorously with air, which can be a safety and quality concern.

To prevent that reaction, Development used a new method that proved highly successful. The entire uranium dioxide feedstock production process subsequently underwent a stringent readiness assessment.

After ensuring the desired particle size is achieved, Y-12 will ship the uranium dioxide feedstock to Atomic Energy of Canada Limited, where it will be fabricated into fuel pins. AECL was selected because it designed the original SLOWPOKE reactor. Y‑12 is also partnering with Cameco to produce the unique zirconium alloy components needed to complete the fuel fabrication. Those components will be shipped to AECL for the fuel pin manufacturing.

Discussing Y‑12’s participation, a Y‑12 Global Threat Reduction Initiative manager noted, “The role to integrate the fabrication was brought to Y‑12 because of our expertise with uranium materials and processes and our successful history of working with the National Nuclear Security Administration’s Global Threat Reduction Initiative on the highly enriched uranium minimization effort. The recurring needs for certain uranium capabilities for fuels and targets for medical isotope production make Y‑12 a unique gem in the Department of Energy/NNSA complex. There is no better team than the one we have here at Y‑12 to complete this challenging project.”