The invention relates to a process for producing proppants, including the following steps: providing red mud, providing fly ash, producing a mixture from the red mud and the fly ash so that the mixture has a first moisture content in the range of 7 to 30 wt. %, producing a granular product from the mixture, and sintering the granular product.

Provided is a red mud-based composite calcium ferrite and a preparation method and use thereof. The preparation method of the red mud-based composite calcium ferrite includes the following steps: mixing red mud and a calcium source, and roasting an obtained mixture in an oxygen-containing atmosphere to obtain the red mud-based composite calcium ferrite; where the calcium source is selected from the group consisting of lime and calcium carbonate. In the present disclosure, the composite calcium ferrite is prepared using a solid waste red mud, with a greatly reduced cost of raw materials; on the other hand, compared with traditional calcium ferrite, the composite calcium ferrite mainly has phase structures of CaFe.sub.2O.sub.4, Ca.sub.2FeAlO.sub.5, and Ca.sub.2Fe.sub.2O.sub.5. Therefore, the composite calcium ferrite has a lower melting point, a higher lime dissolution efficiency, and better fluxing and dephosphorization effects during primary smelting and refining of molten steel, and has broad prospects for use in industry.

The disclosure discloses a method for preparing a multifunctional ecological exterior wall, including: preparing a ceramic board of a ceramic thermal insulation waterproof layer; preparing a ceramic sound-absorbing board of a sound-absorbing layer; and installing a ecological exterior wall: leveling a surface of the wall of a building with cement slurry, and applying a cement bonding layer thereon; laying the ceramic thermal insulation waterproof board on the cement bonding layer, and applying the cement bonding layer on the ceramic board; laying the ceramic sound-absorbing board on the cement bonding layer and reserving a gap used to place a pipe; driving the screw-thread steel bolt from the surface of the ceramic sound-absorbing board into the wall obliquely; installing and fixing the pipe in the gap, which is reserved at the upper of the ceramic sound-absorbing board; planting a green plant on the surface of the ceramic board of the sound-absorbing layer.

Provided is a red mud-based composite calcium ferrite and a preparation method and use thereof. The preparation method of the red mud-based composite calcium ferrite includes the following steps: mixing red mud and a calcium source, and roasting an obtained mixture in an oxygen-containing atmosphere to obtain the red mud-based composite calcium ferrite; where the calcium source is selected from the group consisting of lime and calcium carbonate. In the present disclosure, the composite calcium ferrite is prepared using a solid waste red mud, with a greatly reduced cost of raw materials; on the other hand, compared with traditional calcium ferrite, the composite calcium ferrite mainly has phase structures of CaFe.sub.2O.sub.4, Ca.sub.2FeAlO.sub.5, and Ca.sub.2Fe.sub.2O.sub.5. Therefore, the composite calcium ferrite has a lower melting point, a higher lime dissolution efficiency, and better fluxing and dephosphorization effects during primary smelting and refining of molten steel, and has broad prospects for use in industry.

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 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 ceramic for construction or technical applications, composed of at least one of Municipal Solid Waste Incinerator Bottom Ash (MSWIBA) and other recycled industrial solid waste and different methods of forming such ceramics. Various techniques illustrate how ceramics are formed using at least one of extrusion shaping, dry powder compaction and agglomeration, any of which can be preceded by a pre-treatment process of received feedstock.

A lightweight high-strength ceramsite, comprising solid raw materials and activator as the raw materials, which can be respectively expressed in parts by weight, the solid raw materials: 100 parts, the activator: 1-15 parts; wherein said solid raw materials comprise fly ash: 100 parts, high-alumina fly ash, bauxite and red mud: 6-18 parts, silica fume: 1-5 parts, surfactant: 0.1-3 parts, plasticizer: 6-24 parts; and said activator comprises alkali metal hydroxide: 5-20 parts and alkali metal silicate: 80-95 parts. The lightweight high-strength ceramsite product prepared has a density level of 700-1100 kg/m3 and cylindrical compressive strength of 10-20 MPa, and thus is not susceptible to damage.

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 novel eco-friendly method has been developed for the fabrication of high dense (3.3-5.2 g/cc) red mud based material blocks for shielding high energy X- and -rays. The red mud based material blocks with various densities were fabricated by hot compacting partially melted red mud, red mud:Bi.sub.2O.sub.3, red mud:Ba(OH).sub.2 and red mud:Bi.sub.2O.sub.3:Ba(OH).sub.2 samples at 1150 C., 1000 C., 1050 C. and 1000 C., respectively. This material can be used to build radiation shielding structures in medical diagnosis, radiotherapy, industrial radiography, particle accelerators, food sterilization plants, nuclear power plants, and radioactive material storage rooms, without further structural support unlike lead (concrete walls). It is economically viable and will suppress the accumulation of hazardous red mud and associated environmental pollutions.