Abstract: The present application describes a process for the continuous production of alpha-calcium sulphate hemihydrate, the process comprising the steps of: providing particulate gypsum; providing water; mixing the particulate gypsum and the water to form a gypsum slurry; and maintaining said gypsum slurry under raised pressure and temperature to convert the particulate gypsum into alpha-calcium sulphate hemihydrate and provide an alpha-calcium sulphate hemihydrate slurry. Additionally, the particulate gypsum comprises a D10 value greater than or equal to 2 ?m, a D90 value smaller than or equal to 90 ?m and a D50 value smaller than or equal to 25 ?m. Particulate gypsum for use in the process is also provided.

Abstract: The present disclosure relates to an electrolytic cell for the production of aluminium by reducing alumina. The cell may comprise a sidewall including at least one side block. The side block may comprise an aluminous material having an apparent porosity of less than about 10% and a composition, as a weight percentage on the basis of the aluminous material and for a total of about 100%, such that: Al2O3>about 50%, beta-alumina being less than about 20% of the weight of the aluminous material, oxides that are less reducible than alumina at 1000° C.<about 50%, Na2O<about 3.9%, and other components<about 5%.

Abstract: The invention relates to a melted and cast refractory product having a chemical composition such that, in mass percentages on the basis of the oxides: AI2O3: complement up to 100%; MgO: 26% to 50%; ZrO2: 0.5% to 10.0%; B2O3: <1.5%; SiO2: ?0.5%; Na2O+K2O: ?0.3%; CaO: ?1.0%; Fe2O3+TiO2: <0.55%; other oxide species: <1.0%. In said product, the elementary mass ratio R of the zirconium content to the total boron, fluorine and silicon content is between 2 and 80.

Abstract: The invention relates to a melted and cast refractory product having a chemical composition such that, in mass percentages on the basis of the oxides: Al2O3 : complement up to 100%; MgO: 26% to 45%; ZrO2: 0.5% to 10.0%; B2O3: <1.5%; SiO2: <0.5%; Na2O+K2O: <0.3%; CaO: <1.0%; Fe2O3+TiO2: <0.55%; other oxide species: <1,0%. In said product, the elementary mass ratio R of the zirconium content to the total boron, fluorine and silicon content is between 2 and 80.

Abstract: The present disclosure relates to an electrolytic cell for the production of aluminium by reducing alumina. The cell may comprise a sidewall including at least one side block. The side block may comprise an aluminous material having an apparent porosity of less than about 10% and a composition, as a weight percentage on the basis of the aluminous material and for a total of about 100%, such that: Al2O3>about 50%, beta-alumina being less than about 20% of the weight of the aluminous material, oxides that are less reducible than alumina at 1000° C.<about 50%, Na2O<about 3.9%, and other components<about 5%.

Abstract: The present invention relates to a regenerator comprising a bed (11) of energy storage media (12) placed in a chamber (14), the chamber comprising a shell (34) and a protective layer (22) placed between said shell and said energy storage media, in contact with said energy storage media, having a minimum thickness higher than 50 mm and consisting, at least partially, of a protective material having a composition, in weight percent based on the oxides, such that: Fe2O3+Al2O3+CaO+TiO2+SiO2+Na2O+K2O>80%, and other oxides: complement to 100%.