abstract
The final destination of the wastes generated in the manufacture of pulp paper is one of the growing concerns in this sector since the European regulations are becoming stricter in regard to their landfill. So it is urgent to seek ways for their valorization through incorporation in other product as, although not usually dangerous, the quantities generated are substantial. In this work the residues used were: (i) a calcareous sludge generated in the chemical recovery circuit of the production process; (ii) a biological sludge generated in the secondary wastewater treatment step and (iii) a fly ash from the combustion of biomass in the cogeneration operation. The first stage of was the waste characterization and then different blends were prepared and submitted to distinct firing cycles to obtain Portland clinker, the main component of the ordinary cement. Using only wastes in adjusted proportions and a tuned firing cycle, it was possible to obtain ecological Portland clinker. Moreover, it was possible to reduce, by about 50 C, the firing temperature in relation to the value used in cement industry, which results in economical and procedural benefits. © (2016) Trans Tech Publications.
keywords
Biological water treatment; Cement industry; Cements; Ceramic materials; Characterization; Fly ash; Secondary recovery; Wastewater treatment; Chemical recovery; European regulation; Firing temperature; Portland clinkers; Production process; Raw material sources; Sludge; Waste characterization; Waste incineration
authors
Buruberri L.H., Seabra M.P., Labrincha J.A.
our authors
João António Labrincha Baptista
Full professor
Leire Hernando Buruberri
PhD Student