New Construction Materials: Calcined Paper Sludges as Active Additions
This paper shows the possibility of reutilize paper sludge waste as supplementary cementing material for the cement manufacture. This industrial waste consists essentially of a mixture of organic matter (30%) and inorganic compound, such as calcite and clay minerals. The raw paper sludge does not present pozolanic properties, but once calcined at 650°C during 2 hours, exhibits a good pozolanic activity. Calcined paper sludge was used as partial Portland cement replacements of 0 and 10%. It was a sligth increment in compressive strength for 10 % of substitution from 7 days on. Furthermore, calcined paper sludge reduces the initial and final setting times of cement paste.
Luís Guerra ROSA and Fernanda MARGARIDO
M. Frías et al., "New Construction Materials: Calcined Paper Sludges as Active Additions", Materials Science Forum, Vols. 636-637, pp. 1222-1227, 2010