Oil shale CFBC ash cementation properties in ash fields

The composition, physical/geotechnical properties and cementation of circulating fluidized bed combustion (CFBC) oil shale ash were studied in a large-scale field experiment. Compared to pulverized fuel (PF) combustion oil shale ashes, the CFBC process ashes have lower cementation properties due to their different phase composition. For hydraulic deposition at low ash-water ratios of approximately 1:20, which have been successfully used for the disposal of PF ashes, the physical separation of CFBC ash particles causes a further partition of the cementation phases resulting in weaker geotechnical properties of the ash sediment compared to PF ash-deposits. The hydraulic transport and deposition of CFBC oil shale ash is not suitable at low ash-water ratios, so alternative deposition strategies must be discovered.