A method of treatment of bauxite residue resulting from a Bayer process of bauxite treatment in order to produce a solid product. The method comprises mixing a quantity of the bauxite residue (1) with a quantity of a glass material (2) to form a mixture. Then, compressing the mixture (4) to form a green body, and sintering (5) the green body. After cooling, the sintered green body thereby provides the solid product.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising red mud. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the red mud bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising red mud. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the red mud bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

A well cementation working solution prepared from red mud, slag and waste drilling fluids. The working solution is prepared from the following components in parts by weight: 100 parts of waste drilling fluids, 50-100 parts of slag, 5-50 parts of red mud, 4-7 parts of a suspension stabilizer, 1-7 parts of an activating aid, 0.5-5 parts of an anti-pollution agent and 0.4-3.5 parts of a diluent. The waste drilling fluids are waste waterborne drilling fluids. The slag is blast furnace slag or vanadium-titanium slag. The suspension stabilizer is sodium bentonite, carboxymethyl cellulose or a mixture of sodium bentonite and carboxymethyl cellulose. The activating aid is sodium metasilicate nonahydrate, sodium carbonate or a mixture of sodium metasilicate nonahydrate and sodium carbonate. The anti-pollution agent is sodium salicylate, potassium citrate or a mixture of sodium salicylate and potassium citrate. The diluent is sodium lignin sulfonate.

A well cementation working solution prepared from red mud, slag and waste drilling fluids. The working solution is prepared from the following components in parts by weight: 100 parts of waste drilling fluids, 50-100 parts of slag, 5-50 parts of red mud, 4-7 parts of a suspension stabilizer, 1-7 parts of an activating aid, 0.5-5 parts of an anti-pollution agent and 0.4-3.5 parts of a diluent. The waste drilling fluids are waste waterborne drilling fluids. The slag is blast furnace slag or vanadium-titanium slag. The suspension stabilizer is sodium bentonite, carboxymethyl cellulose or a mixture of sodium bentonite and carboxymethyl cellulose. The activating aid is sodium metasilicate nonahydrate, sodium carbonate or a mixture of sodium metasilicate nonahydrate and sodium carbonate. The anti-pollution agent is sodium salicylate, potassium citrate or a mixture of sodium salicylate and potassium citrate. The diluent is sodium lignin sulfonate.

The present invention relates to a modified red mud/a modified bauxite residue and also to processes for the production thereof and to a storage medium comprising a modified red mud, to a heat storage means comprising a storage medium and to numerous uses of a modified red mud as storage medium, in particular in a heat storage means. The modified red mud contains the following components: haematite (Fe.sub.2O.sub.3), corundum (Al.sub.2O.sub.3), rutile (TiO.sub.2) and/or anatase (TiO.sub.2), quartz (SiO.sub.2), optionally perowskite (CaTiO.sub.3) and optionally pseudobrookite ((Fe.sup.3+,Fe.sup.2+).sub.2(Ti,Fe.sup.3+)O.sub.5), nepheline ((Na,K)[AlSiO.sub.4]) and/or hauynite ((Na,Ca).sub.4-8[Al.sub.6Si.sub.6O.sub.24(SO.sub.4)]), wherein the modified red mud is substantially free from Na.sub.2O and/or glass. A novel material is thus provided, and the production thereof for use as a storage medium in a sensitive energy storage system in the low-, medium- or high-temperature range is described.

The present invention relates to a modified red mud/a modified bauxite residue and also to processes for the production thereof and to a storage medium comprising a modified red mud, to a heat storage means comprising a storage medium and to numerous uses of a modified red mud as storage medium, in particular in a heat storage means. The modified red mud contains the following components: haematite (Fe.sub.2O.sub.3), corundum (Al.sub.2O.sub.3), rutile (TiO.sub.2) and/or anatase (TiO.sub.2), quartz (SiO.sub.2), optionally perowskite (CaTiO.sub.3) and optionally pseudobrookite ((Fe.sup.3+,Fe.sup.2+).sub.2(Ti,Fe.sup.3+)O.sub.5), nepheline ((Na,K)[AlSiO.sub.4]) and/or hauynite ((Na,Ca).sub.4-8[Al.sub.6Si.sub.6O.sub.24(SO.sub.4)]), wherein the modified red mud is substantially free from Na.sub.2O and/or glass. A novel material is thus provided, and the production thereof for use as a storage medium in a sensitive energy storage system in the low-, medium- or high-temperature range is described.

Provided herein are methods and compositions utilizing one or more cementitious replacement materials, one or more alkaline activating materials, and, optionally one or more bonding materials and/or one or more setting time enhancer materials.

Provided herein are methods and compositions utilizing one or more cementitious replacement materials, one or more alkaline activating materials, and, optionally one or more bonding materials and/or one or more setting time enhancer materials.

The present invention discloses a method of preparing an alkali activation material by using red mud-based wet grinding and carbon sequestration and an application thereof. The preparation method includes: (1) adding water, red mud, a crystalline control agent, and a grinding aid into a wet grinding carbon sequestration apparatus to perform wet grinding, and simultaneously introducing CO.sub.2 until a slurry pH reaches 7 to 7.5; and removing wet grinding balls by a sieve to obtain a slurry A; (2) adding carbide slag, water and a water reducer to a wet planetary ball grinder tank for wet grinding, and removing wet grinding balls by a sieve to obtain a slurry B; (3) taking 50 to 80 parts of the slurry A and 20 to 50 parts of the slurry B and mixing them to obtain an alkali activation material.