Process to inert non-swelling clays
A process to inert non-swelling clays in at least one mineral component intended for the preparation of a hydraulic composition, including the addition, to the hydraulic composition, to the mineral component or to one of the other constituents of the hydraulic composition, of an organic molecule having a cationic charge density strictly less than 0.5 meq/g and including at least two atoms each being capable of forming at least one hydrogen bond.
1. A process to prepare a hydraulic composition comprising a mineral component in which non-swelling clays are inerted, comprising the steps of:
a. preparing an aqueous composition comprising an organic molecule, wherein the organic molecule has a cationic charge density of strictly less than 0.5 meq/g and comprising at least two atoms that are each capable of forming at least one hydrogen bond, wherein the organic molecule is obtained by a stage of polymerization of at least one vinyl acetate monomer and a stage of hydrolysis, a degree of hydrolysis of the organic molecule being less than 93%, and
b. adding the aqueous composition obtained in step a) to the mineral component including non-swelling clays, the mineral component having a content of clay of 0.5 to 5% by mass, the mineral component being present in a constituent of the hydraulic composition.
2. The process according to claim 1 , wherein the organic molecule is neutral.
3. The process according to claim 1 , wherein the organic molecule is a polyvinyl alcohol.
4. The process according to claim 1 , wherein the hydraulic composition is a concrete or a mortar.
5. A mixture to inert non-swelling clays in at least one mineral component intended for the preparation of a hydraulic composition, comprising:
an organic molecule wherein the organic molecule has a cationic charge density of strictly less than 0.5 meq/g and comprises at least two atoms that are each capable of forming at least one hydrogen bond, and wherein the organic molecule is obtained by a stage of polymerization of at least one vinyl acetate monomer and a stage of hydrolysis, a degree of hydrolysis of the organic molecule being less than 93%,
an inerting agent for swelling clays and a superplasticizer, said organic molecule, said inerting agent for swelling clays and said superplasticizer being the main polymers in the mixture, and
an antifoaming agent, a biocide or both an antifoaming agent and a biocide.
6. The mixture according to claim 5 , wherein the organic molecule is neutral.
7. The mixture according to claim 5 , to inert swelling and non-swelling clays in the mineral component, further comprising a cationic polymer having a cationic charge density greater than 0.5 meq/g and an intrinsic viscosity less than 1 dl/g.
8. The mixture according to claim 5 , wherein the organic molecule is a polyvinyl alcohol.
9. A process for the production of a hydraulic composition, comprising bringing into contact the mixture according to claim 5 with a mixing water and hydraulic binder.
10. The process according to claim 1 , wherein the mineral component is sand, a mineral addition, a hydraulic binder or any combination thereof.
11. The process according to claim 10 , wherein the mineral addition is fly ash, a pozzolanic material, silica fume, a slag, calcined shale, a calcareous addition, a siliceous addition or any combination thereof.
12. The process according to claim 10 , wherein the hydraulic binder is cement or plaster.
13. The process according to claim 5 , wherein the mineral component is sand, a mineral addition, a hydraulic binder or any combination thereof.
14. A process to prepare a hydraulic composition comprising a mineral component in which swelling and non-swelling clays are inerted, comprising the steps of
a. preparing an aqueous composition comprising an organic molecule, wherein the organic molecule has a cationic charge density of strictly less than 0.5 meq/g and comprising at least two atoms that are each capable of forming at least one hydrogen bond, wherein the organic molecule is obtained by a stage of polymerization of at least one vinyl acetate monomer and a stage of hydrolysis, a degree of hydrolysis of the organic molecule being less than 93%;
b. preparing a composition comprising a cationic polymer, wherein the cationic polymer has a cationic charge density greater than 0.5 meq/g and an intrinsic viscosity less than 1 dl/g, and
c. adding the aqueous composition obtained in step a) and the composition obtained in step b) to, the mineral component including swelling clays and non-swelling clays, the mineral component having a content of clay of 0.5 to 5% by mass, the mineral component being present in a constituent of the hydraulic composition.
15. The process according to claim 14 , wherein the organic molecule having a cationic charge density of strictly less than 0.5 meq/g is a polyvinyl alcohol.
16. The process according to claim 1 , wherein the aqueous composition is sprayed on the mineral component including non-swelling clays.
17. The process according to claim 1 , wherein the hydraulic composition further comprises a superplasticizer.
18. The mixture according to claim 5 , wherein the mixture is an aqueous composition.
19. The process according to claim 14 , wherein the hydraulic composition further comprises a superplasticizer.
20. The process according to claim 14 , wherein the intrinsic viscosity is less than 0.6 dl/g.