Abstract

Geopolymer Formulations for Radioactive Waste Disposal Applications: Scale-Up to 100 Kg Blocks

Author(s): RD Ambashta, TC Alex, Rashmi Singla, DP Sahoo, P Srivastava, YC Shivakumar, G Sugilal, Sanjay Kumar

Geopolymerisation is a promising matrix as an engineered barrier for radionuclide disposal. This study, besides optimisation of parameters for preparing a good geopolymer matrix for radionuclide immobilization utilising industrial wastes such as Fly Ash (FA) and Ground Granulated Blast Furnace Slag (GGBFS), mainly focuses on scale-up geopolymer blocks to 100 kg blocks (perhaps the first time!), required for actual immobilization at plant sites. The paper discusses the details of the formulations, characteristics of the large geopolymer blocks vis-à-vis lab-scale products, the challenges and their experience in the scale-up process, and the way ahead towards the realization of geopolymers at the industrial level. It is to be noted that the precursors used in the process, fly ash and BF slag, are secondary (not virgin) resources and are environmentally friendly. The studies reveal that the characteristics suit the intended application.