External beams of radiation can be used to accelerate radiolytic processes inevitably occurring in sludge wasteforms. At the Diamond Light Source (DLS) we have pioneered a new technique to follow the full creation and transport dynamics of key products (e.g. hydrogen). We can perform a full study of the radiolytic yield and diffusivity of hydrogen using this approach for a given sludge in typically a few hours – results show elevated yields and reduced diffusivity in brucite-water systems. Furthermore, we characterize the energy transfer between these two phases using Monte Carlo simulation [e.g. DOI:10.1038/srep00018 (2011)]. Using DCF-based irradiator systems coupled to a GC system we can make complimentary measurements of the total product yield (gas products or volatiles). Together these techniques allow us to assess the overall importance of radiation driven processes and then to develop a mechanistic picture of the processes at work. For zeta-potential measurements, we will use the technique of Nakuta et al [DOI:10.1016/j.apt.2015.01.017], developing a similar apparatus, additionally incorporating our small irradiator system, thereby allowing us to assess changes in zeta-potential due to the effects of radiation. As a final summative aspect of the project, we will radiolytically generate hydrogen (closed cell) and then examine the formation of bubbles.
Academic Lead: Fred Currell
Researcher: Mel O’Leary
Location: The University of Manchester