This research was supported by Engineering and Physical Sciences Research Council through the Keeping the Nuclear Option Open initiative and carried out at the Department of Engineering Materials University of Sheffield

The nuclear industry worldwide has stored large amounts of waste material in ponds, silos and tanks that need processing. In the UK there are significant quantities of radioactive sludge that have arisen from the corrosion of early Magnox fuel cans. These sludges are polydisperse colloidal systems based on magnesium hydroxide in an aqueous alkaline medium. More generally, however, at other sites throughout the world radioactive sludge can have alternative composition [1] [2]. The development of methods and machinery for the recovery and immobilisation of these radioactive waste slurries is long overdue and currently poses a particularly awkward problem. Blockages of radioactive material in engineering equipment are particularly undesirable and plant must be designed to run for its lifetime with little or no intervention. Furthermore, the monitoring of pumping processes may be difficult because of shielding [1]. Hence, in the nuclear industry in particular, computer simulation on many scales is being used to inform the design of recovery technologies. An understanding of sludge rheology is central to the optimisation of machinery for the recovery of these materials. The aim of this study was to develop investigate the suitability of mesoscopic models, in particular dissipative particle dynamics, for the simulation of these materials.

Brief description

Some notes are given in the following link: DPD simulations (pdf)

References

1. Martin Whittle, Karl P. Travis; Dynamic Simulations of colloids by core-modified dissipative particle dynamics. J. Chem. Phys. 132, 124906-124916, (2010. Abstract