This work is part of a broad research conducted to study the re-use of industrial wastes in an economical and environmentally sustainable manner. Re-use of lightweight ash from the paper mill industry in the manufacture of plaster blends is examined in this study. Lightweight ash is produced during the combustion process of de-inking sludge. Studies demonstrate that lightweight ash is an excellent ingredient in the production of cement mortars and/or pozzolanic mortars to be used as plaster. In this research, ash valorization was researched by investigating the efficacy of the ash as it is, as a substitute for very fine sand.

If properly mixed at an optimal mix proportion, the mechanical strength ranges from 4÷10MPa with specific gravity between 1150 and 1350 Kg/m³. Water absorption may be reduced to a very low level with silane-based surface treatment.