Influence of ash type and mixing methods on workability and compressive strength when using Greenlandic MSWI fly ash as cement replacement in mortar

Municipal solid waste incineration is the preferred management option in the six largest Greenlandic cities to minimize the volume of waste in the disposal sites and to produce district heating. Currently, fly ash from these six small scale waste incinerators in Greenland is shipped to Norway, which is a considerable cost for the municipalities. In the future, municipal solid waste will be incinerated at new state-of-the-art incineration plants in the two largest cities in Greenland, while closing the old ones. Both for economic reasons to avoid high transportation and disposal costs abroad, but also for using local industrial by-products in construction in Greenland, MSWI fly has showed promising results as an supplementary cementitious material (SCM) [1]. One challenge though, is how to mix the MSWI fly ash in concrete mixes and the possible consequences on the workability [2,3]. Therefore, in this study, it was investigated how different mixing methods influenced the workability and compressive strength of both cyclone and electrostatic precipitator fly ash from Greenland.