The composition and properties of ash in the context of the modernisation of oil shale industry

The modernisation of the oil shale (OS) industry in Estonia over the last decade has also led to significant changes in the composition and binding properties of the ash generated as a by-product. These changes also influence the environmental impact that the ash can have. In the current investigation, oil shale ash (OSA) samples were collected from different points along the ash separation systems of a large pulverized fuel combustion plant (LCP), various points in a circulating fluidized bed (CFB) combustion plant, and from an oil shale pyrolysis plant that utilises oil shale to produce liquid fuels. The results obtained can be used for optimising the deposition conditions, as well as guiding utilisation-recycling processes for ash generated from changing oil shale composition and characteristics. When it comes to developing the circular economy aspects of oil shale utilisation, mapping out the properties