Along with the increase in popularity of the sewage sludge thermal treatment methods in Poland
resulting from the implementation of European Union law, a management problem with ash, which is produced
as a result of this process, appeared. The paper analyses the chemical composition and physical properties of fl y
ash from thermal treatment of municipal sewage sludge in terms of its use in concrete technologies in relation to
EN 450-1 Fly ash for concrete. Defi nition, specifi cations and conformity criteria (2012) and EN 197-1 Cement.
Composition, specifi cations and conformity criteria for common cements (2011) standards. The tested material did
not meet the requirements related to use of fl y ash for concrete production (chemical composition, low activity
index, high water demand and fi neness), and as main and minor components for cement production. On the basis
of the carried out research and analyses, it was found that the hardening slurry technology creates the greatest
possibilities related to the management of fl y ash from thermal treatment of municipal sewage sludge.