The effect of binary pozzolan mix on the mineralogical changes in the ternary activated paper sludge-fly ash-Ca(OH)2 system

► The influence of different paper sludges (LS, IS) on the mineralogy is evaluated. ► Laboratory scale activation predominates LDH phases in LS/FA blend. ► Meanwhile for the IS/FA system were C4AC¯H12 and LDH during the first 28 days. ► Ca/Si ratios greater than 0.5 and 1 for the hemicarboaluminate and LDH phases. ► The mixture of LS (or IS) and FA can successfully be used as binary pozzolans.