Additives for a hydraulic binder based on belite-calcium-sulphoaluminate-ferrite clinker
AssigneeLafarge
InventorsGunther Walenta, Ellis Gartner, Vincent Morin
Life of this patent
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Abstract
A composition includes at least, in % expressed by mass relative to the total mass of the composition, from 0.01 to 3% of polycarboxylic acid or salts thereof, the polycarboxylic acid including 2 to 4 carboxyl groups per molecule; and from 97 to 99.99% of a Belite-Calcium-Sulphoaluminate-Ferrite clinker (BCSAF clinker).
Claims19
A composition comprising, in % expressed by mass relative to the total mass of the composition,
- from 0.01 to 3% of polycarboxylic acid or a salt thereof, said polycarboxylic acid comprising 2 to 4 carboxyl groups per molecule;
- and
- from 97 to 99.99% of a Belite-Calcium-Sulphoaluminate-Ferrite clinker (BCSAF clinker) comprising, in % expressed by mass relative to the total mass of BCSAF clinker
- from 5 to 30%, of a calcium aluminoferrite phase of a composition corresponding to the general formula C2AXF1−X), wherein X is from 0.2 to 0.8, wherein C corresponds to CaO, A corresponds to Al2O3 and F corresponds to Fe2O3;
- from 10 to 35%, of a calcium sulfoaluminate phase corresponding to the general formula C4A3$, wherein $ corresponds to SO3;
- from 40 to 75% of belite phase corresponding to the general formula C2S, wherein S corresponds to SiO2;
- from 0.01 to 10% of one or more minor phases selected from calcium sulphates, alkali sulphates, perovskite, gehlenite, free lime and periclase, and/or a vitreous phase,
- and for which the total of the percentages of said phases is greater than or equal to 97%.
A concrete or mortar comprising a cement including a composition comprising, in % expressed by mass relative to the total mass of the composition, from 0.01 to 3% of a polycarboxylic acid or a salt thereof, said polycarboxylic acid comprising 2 to 4 carboxyl groups per molecule, and from 97 to 99.99% of a belite-calcium-sulphoaluminate-ferrite clinker comprising, in % expressed by mass relative to the total mass of belite-calcium-sulphoaluminate-ferrite clinker
- from 5 to 30%, of a calcium aluminoferrite phase of a composition corresponding to the general formula C2AXF(1−X), wherein X is from 0.2 to 0.8, wherein C corresponds to CaO, A corresponds to Al2O3 and F corresponds to Fe2O3;
- from 10 to 35%, of a calcium sulfoaluminate phase C4A2$, wherein $ corresponds to SO3;
- from 40 to 75% of belite phase C2S, wherein S corresponds to SiO2;
- from 0.01 to 10% of one or more minor phases selected from calcium sulphates, alkali sulphates, perovskite, gehlenite, free lime and periclase, and/or a vitreous phase,
- and for which the total of the percentages of said phases is greater than or equal to 97%.
A method comprising increasing a mechanical strength of a cement after setting, the cement including a composition comprising in % expressed by mass relative to the total mass of the composition from 97 to 99.99% of a belite-calcium-sulphoaluminate-ferrite clinker, by adding in % expressed by mass relative to the total mass of the composition from 0.01 to 3% of a polycarboxylic acid or a salt thereof to the belite-calcium-sulphoaluminate-ferrite clinker, said polycarboxylic acid comprising 2 to 4 carboxyl groups per molecule, wherein the belite-calcium-sulphoaluminate-ferrite clinker includes, in % expressed by mass relative to the total mass of belite-calcium-sulphoaluminate-ferrite clinker
- from 5 to 30%, of a calcium aluminoferrite phase of a composition corresponding to the general formula C2AXF(1−X), wherein X is from 0.2 to 0.8, wherein X is from 0.2 to 0.8, C corresponds to CaO, A corresponds to Al2O3 and F corresponds to Fe2O3;
- from 10 to 35%, of a calcium sulfoaluminate phase C4A3$, wherein $ corresponds to SO3;
- from 40 to 75% of belite phase C2S, wherein S corresponds to SiO2;
- from 0.01 to 10% of one or more minor phases selected from calcium sulphates, alkali sulphates, perovskite, gehlenite, free lime and periclase, and/or a vitreous phase,
- and for which the total of the percentages of said phases is greater than or equal to 97%.
A concrete or mortar comprising:
- a polycarboxylic acid or a salt thereof, said polycarboxylic acid comprising 2 to 4 carboxyl groups per molecule;
- and
- a cement including a source of calcium sulphate and a belite-calcium-sulphoaluminate-ferrite clinker that includes, in % expressed by mass relative to the total mass of belite-calcium-sulphoaluminate-ferrite clinker,
- from 5 to 30% of a calcium aluminoferrite phase of a composition corresponding to the general formula C2AXF(1−X), wherein X is from 0.2 to 0.8, C corresponds to CaO, A corresponds to Al2O3 and F corresponds to Fe2O3;
- from 10 to 35% of a calcium sulfoaluminate phase C4A3$, wherein $ corresponds to SO3;
- from 40 to 75% of belite phase C2S, wherein S corresponds to SiO2;
- from 0.01 to 10% of one or more minor phases selected from calcium sulphates, alkali sulphates, perovskite, gehlenite, free lime and periclase, and/or a vitreous phase,
- wherein the total of the percentages of said phases is greater than or equal to 97%.
Dependencies are inferred from the claim text.