Glass - Back to the Future!

Presenting Author:
James Stevens

article posted 31 March 2016

James StevensJames gained a first class masters in physics from the University of Hull as a mature student. He now works for the NNL as technical lead for a number of projects supporting the Sellafield waste vitrification plant and more recently as a run controller for the vitrification test rig.

Underpinning the transition from MW to Ca/Zn glass frit for HLW vitrification on UK WVP

James R. Stevens
National Nuclear Laboratory, Sellafield, Seascale, Cumbria CA20 1PG

Washout of the Sellafield Highly Active Storage Tanks is expected to produce a significant amount of zirconium molybdate solids that will need to be incorporated into the vitrified product of the waste vitrification plant. After the development of a suitable new glass formulation by National Nuclear Laboratory scientists, work has been undertaken to underpin the transition from the currently used MW glass frit to the new Ca/Zn formulation to ensure consistency of: operability, melt behaviour and product quality, encompassing a broad range of factors.

In this presentation, the path from requirement for a new glass formulation to the production of full- scale glass batches ready to be used on WVP will be described. The glass development methodology, selection criteria and testing methods will be outlined with accompanying results, alongside the methods and procedures, laboratory work and vitrification test rig campaigns employed to achieve a satisfactory underpinning of a new glass formulation on a nuclear licenced site.