Preparation of clinker from paper pulp industry wastes

• Published in: Journal of hazardous materials Vol. 286; pp. 252 - 260
• Main Authors: Buruberri, Leire H., Seabra, M.P., Labrincha, J.A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 09.04.2015
• Subjects: Biomass fly ash; Calcium Compounds - chemistry; Chemical Industry; Clinker; Coal Ash - chemistry; Compressive Strength; Construction Materials; Industrial Waste - analysis; Industrial Waste - prevention & control; Mortars; Oxides - chemistry; Paper pulp wastes; Particle Size; Sewage - chemistry; Sludge; Waste Management - methods; Biomass fly ash; Mortars; Paper pulp wastes; Clinker; Sludge
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2014.12.053

•Valorization of the pulp paper industry wastes (lime mud, biological sludge and fly ash).•Despite the fly ash constrains (high chloride content) an application for it was found.•Development of eco-clinkers (betilic and Portland) only from industrial wastes.•Decrease (of about 60°C) of the eco-Portland clinker processing temperature. The production of paper pulp by the Kraft method generates considerable amounts of wastes. Namely, lime mud generated in the recovery circuit of chemical reagents, biological sludge from the wastewater treatment of wood digestion process and fly ash collected in the fluidized bed combustor used to generate electricity from biomass burning. The final destination of such wastes is an important concern, since environmental regulations are becoming stricter regarding their landfill. Driven by this fact, industries are looking for more sustainable solutions, such as the recycling in distinct products. This work tested these wastes as secondary raw materials to produce clinker/cement that was then experienced in mortar formulations. The first step involved the residues detailed characterization and a generated amounts survey. Then, specific but simple steps were suggested, aiming to facilitate transport and manipulation. Distinct blends were prepared and fired in order to get belitic and Portland clinkers. The Portland clinkers were processed at lower temperatures than the normally used in the industry due to the presence of mineralizing impurities in some wastes. Belite-based cements were used to produce mortars that developed satisfactory mechanical strength and did not reveal signs of deterioration or durability weaknesses.