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 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 ceramsite produced by using a river/lake/sea sludge and seashell powder as raw materials and a preparation method thereof are provided. The ceramsite is made of the following raw materials in parts by weight: 15-50 parts of shell powder, 5-15 parts of kaolin, 1-5 parts of peat ash, 15-30 parts of siliceous shale, 15-40 parts of furnace slag, 10-20 parts of fly ash, 15-40 parts of zeolite, 10-30 parts of river/lake/sea sludge, and 10-25 parts of peat. The shell powder is pulverized to a particle size of 60-200 mesh in fineness. A content of silica in the siliceous shale is 87.0%-89.5%. The preparation method of the ceramsite includes the following steps: taking raw materials, pulverizing, stirring, granulating, calcining, and naturally cooling, so as to obtain the ceramsite.

A ceramsite produced by using a river/lake/sea sludge and seashell powder as raw materials and a preparation method thereof are provided. The ceramsite is made of the following raw materials in parts by weight: 15-50 parts of shell powder, 5-15 parts of kaolin, 1-5 parts of peat ash, 15-30 parts of siliceous shale, 15-40 parts of furnace slag, 10-20 parts of fly ash, 15-40 parts of zeolite, 10-30 parts of river/lake/sea sludge, and 10-25 parts of peat. The shell powder is pulverized to a particle size of 60-200 mesh in fineness. A content of silica in the siliceous shale is 87.0%-89.5%. The preparation method of the ceramsite includes the following steps: taking raw materials, pulverizing, stirring, granulating, calcining, and naturally cooling, so as to obtain the ceramsite.

Plant for the recovery of spent refractory material in steel plants, comprising at least one receiving area (1) for said refractory material, at least one material sieving area (2), at least one magnetic separation area (3) and at least one sorting area (4).

Said receiving area (1) communicates with a first sieving area (2) comprising first sieving means intended to divide said refractory material in at least two fractions, of which a coarse fraction and a fine fraction, on the basis of the size of said material.

There is further provided a second sieving area (21) comprising second sieving means intended to divide said fine fraction into at least two further sub-fractions (A, B, C) on the basis of size.

The present invention relates to a heating cooker using a ceramic heating element and a manufacturing method thereof, the method comprising: a cooker body preparation step; a heating element material preparation step of preparing any one or more selected from among mill scale, steelmaking slag and magnetite (Fe.sub.3O.sub.4); an inorganic binder preparation step of preparing, as an inorganic binder, a colloidal silica sol having a colloidal silica content of 8 to 30 wt %; a mixing step of mixing 20 to 40 parts by weight of the colloidal silica sol as the inorganic binder with 100 parts by weight of the heating element material, thereby making a heating material paste; an application step of applying the heating element paste to the bottom of the cooker body; and a drying and curing step of drying and curing the heating element paste, thereby forming a solid heating element.

Materials that seamlessly transition from opaque to transparent or translucent, such as advanced geopolymer-based ceramics to glass structures, which can be directly and seamlessly bonded without the use of an intermediate adhesive or use of a frame are disclosed. That is, a GP-based ceramic to glass structure can be bonded directly and seamlessly and without any mechanical joints, connective tissue or adhesives such as caulking or epoxy. Such ceramic to glass materials can be prepared by sintering an engineered geopolymer with glass to form the geopolymer-based advanced ceramic-glass structure in which the interface is visually abruptly or in which the material is a graded composition with a controlled transition from one material to the other.

Materials that seamlessly transition from opaque to transparent or translucent, such as advanced geopolymer-based ceramics to glass structures, which can be directly and seamlessly bonded without the use of an intermediate adhesive or use of a frame are disclosed. That is, a GP-based ceramic to glass structure can be bonded directly and seamlessly and without any mechanical joints, connective tissue or adhesives such as caulking or epoxy. Such ceramic to glass materials can be prepared by sintering an engineered geopolymer with glass to form the geopolymer-based advanced ceramic-glass structure in which the interface is visually abruptly or in which the material is a graded composition with a controlled transition from one material to the other.

The present invention provides a method of preparing a proppant material by heating a reaction mixture comprising a plurality of oxides in a reactive atmosphere to a temperature above the melting point of the reaction mixture to form a melt, and then allowing the melt to solidify in a mold in the form of spherical particles. The present invention also provides a method of preparing a proppant material by heating a reaction mixture comprising a plurality of oxides and one or more additives in a reactive atmosphere to a temperature below the melting point of the reaction mixture to form a powder including one or more reaction products, and then processing the powder to form spherical particles. The present invention also provides a proppant material including spherical particles characterized by a specific gravity of about 1.0 to 3.0 and a crush strength of at least about 10,000 psi.

The present invention provides a method of preparing a proppant material by heating a reaction mixture comprising a plurality of oxides in a reactive atmosphere to a temperature above the melting point of the reaction mixture to form a melt, and then allowing the melt to solidify in a mold in the form of spherical particles. The present invention also provides a method of preparing a proppant material by heating a reaction mixture comprising a plurality of oxides and one or more additives in a reactive atmosphere to a temperature below the melting point of the reaction mixture to form a powder including one or more reaction products, and then processing the powder to form spherical particles. The present invention also provides a proppant material including spherical particles characterized by a specific gravity of about 1.0 to 3.0 and a crush strength of at least about 10,000 psi.