Abrégé

A method for preparing lightweight clay-based aggregates, the aggregates being suitable for use notably in civil engineering works, in particular road uses, and construction. The method for preparing lightweight aggregates includes at least the following steps: a) a step of granulating a clay-based mixture, so as to obtain aggregates, b) a step of drying the aggregates obtained, so as to obtain dried aggregates, c) a step of heat treatment of the dried aggregates, this step having two successive substeps: i) a first substep of heat treatment carried out under a reducing atmosphere at a temperature Ti of between 900° C. and 1200° C. approximately, ii) a second substep of heat treatment carried out under an oxidizing atmosphere at a temperature T2 of between 1050° C. and 1300° C. approximately, and d) a step of cooling the aggregates.

Classes IPC  ?

• C04B 18/02 - Matières agglomérées
• C04B 18/04 - DéchetsRésidus
• C04B 20/04 - Traitement thermique
• C04B 111/00 - Fonction, propriétés ou utilisation des mortiers, du béton ou de la pierre artificielle
• C04B 111/40 - Matériaux poreux ou légers

Abrégé

The present invention relates to a method for preparing lightweight clay-based aggregates, said aggregates being suitable for use notably in civil engineering works, in particular road uses, and construction. The invention thus firstly relates to a method for preparing lightweight aggregates comprising at least the following steps: a) a step of granulating a clay-based mixture, so as to obtain aggregates, b) a step of drying the aggregates obtained, so as to obtain dried aggregates, c) a step of heat treatment of the dried aggregates, said step comprising two successive substeps: i) a first substep of heat treatment carried out under a reducing atmosphere at a temperature T1 of between 900°C and 1200°C approximately, ii) a second substep of heat treatment carried out under an oxidizing atmosphere at a temperature T2 of between 1050°C and 1300°C approximately, and d) a step of cooling the aggregates.

Classes IPC  ?

• C04B 33/132 - DéchetsRésidus
• C04B 33/04 - ArgileKaolin
• C04B 33/30 - Séchage
• C04B 33/32 - Procédés de cuisson
• C04B 35/626 - Préparation ou traitement des poudres individuellement ou par fournées
• B09B 3/25 - Agglomération, liaison ou encapsulation de déchets solides à l'aide de liants ou de matrices minéraux
• B09B 3/40 - Destruction de déchets solides ou transformation de déchets solides en quelque chose d'utile ou d'inoffensif impliquant un traitement thermique, p. ex. évaporation
• C04B 18/02 - Matières agglomérées
• C04B 20/06 - Argile expansée, perlite, vermiculite ou matières granuleuses analogues
• C04B 111/00 - Fonction, propriétés ou utilisation des mortiers, du béton ou de la pierre artificielle