Replacement of hydrated lime by dregs in the production of mortars

The pulp industry in Brazil has been growing every year, producing huge volume of solid waste, which has been massively disposed off in landfills. Among the waste stream of the Kraft process, there is a residue called dregs, this by-product can be used as possible material in the replacement of hydrated lime (HL) in mortars. In this investigation, mortars were made with 0% and 100% of substitution of HL by dregs. For these mortars, splitting tensile strength, flexural tensile strength, water absorption, water retention, air content, and adherence tensile strength tests were carried out to evaluate the technological properties and compare them with the reference mortar (100% HL). The results show the incorporation of dregs enhances the mechanical and physical properties of the mortar and is technologically feasible. The analytical testing results showed the strength gain of the mortar with dregs was attributed to the pore refinement and filler effect.