Abstract

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.

IPC Classes  ?

• C04B 18/02 - Agglomerated materials
• C04B 18/04 - Waste materialsRefuse
• C04B 20/04 - Heat treatment
• C04B 111/00 - Function, property or use of the mortars, concrete or artificial stone
• C04B 111/40 - Porous or lightweight materials

Abstract

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.

IPC Classes  ?

• B09B 3/25 - Agglomeration, binding or encapsulation of solid waste using mineral binders or matrix
• B09B 3/40 - Destroying solid waste or transforming solid waste into something useful or harmless involving thermal treatment, e.g. evaporation
• C04B 18/02 - Agglomerated materials
• C04B 20/06 - Expanding clay, perlite, vermiculite or like granular materials
• C04B 33/04 - ClayKaolin
• C04B 33/132 - Waste materialsRefuse
• C04B 33/30 - Drying methods

Abstract

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.

IPC Classes  ?

• C04B 33/132 - Waste materialsRefuse
• C04B 33/04 - ClayKaolin
• C04B 33/30 - Drying methods
• C04B 33/32 - Burning methods
• C04B 35/626 - Preparing or treating the powders individually or as batches
• B09B 3/25 - Agglomeration, binding or encapsulation of solid waste using mineral binders or matrix
• B09B 3/40 - Destroying solid waste or transforming solid waste into something useful or harmless involving thermal treatment, e.g. evaporation
• C04B 18/02 - Agglomerated materials
• C04B 20/06 - Expanding clay, perlite, vermiculite or like granular materials
• C04B 111/00 - Function, property or use of the mortars, concrete or artificial stone