An apparatus for thermally treating mineral solids includes a preheater, a separating apparatus arranged at an outlet of an entrained flow reactor, and a thermal treatment zone at an outlet of a gas stream of the separating apparatus, with an outlet of the treatment zone being connected to an inlet of the preheater for the gas stream. A process may involve preheating a mineral material, thermally treating the mineral material in an entrained flow reactor in a reducing atmosphere for reducing coloring metal compounds, separating a solid/gas mixture from the entrained flow reactor in a separating apparatus, oxidizing reducing constituents of a gas from the separating apparatus in a thermal treatment zone between the separating apparatus and the preheater via supplied oxygen, and supplying gas emerging from the thermal treatment zone to the preheater and thereby utilizing thermal energy recovered in the thermal treatment zone by transfer to mineral material

An installation for thermal treatment of free-floating raw material, in particular cement raw meal and/or mineral products, may include a riser line through which hot gases can flow. The riser line has at least one fuel inlet for introducing fuel into the riser line. The riser line has at least one raw meal inlet for introducing raw meal into the riser line, which raw meal inlet is arranged upstream of the fuel inlet in a flow direction of gas inside the riser line. Further, a method for thermal treatment of free-floating raw material may involve introducing fuel via a fuel inlet into a riser line for guiding hot gases and introducing raw meal into the riser line. The raw meal is introduced into the riser line upstream of the fuel inlet in the flow direction.

The disclosure discloses a production method for producing cement and co-producing sulfuric acid from phosphogypsum. The method includes: pretreating and purifying the phosphogypsum to reduce insoluble phosphorus, water-soluble phosphorus impurities, and most free water in the phosphogypsum, directly feeding the materials kneaded and granulated with a reducing agent into a reduction and decomposition integrated rotary kiln with a fluidized preheating function, and controlling to carry out step-by-step heating, drying, dehydration, reduction and decomposition in a gas phase atmosphere under pulverized coal combustion; using sulfur dioxide gas generated after reduction and decomposition to produce the sulfuric acid after dust removal and purification; making the materials after reduction and decomposition enter an oxidation calcining kiln for sintering a cement clinker, and controlling to heat, mineralize and sinter the cement clinker in the gas phase atmosphere under the pulverized coal combustion.

There is provided high temperature furnaces, calcining, pyrolysis and other high temperature manufacturing processes, composition rearrangements, and equipment. Generally, embodiments the present inventions relate to systems, equipment and processes using oxyfuel for high temperature processing of materials for the production of cements having a particle size distribution from about 0.1 μm to about 150 μm.

There is provided high temperature furnaces, calcining, pyrolysis and other high temperature manufacturing processes, composition rearrangements, and equipment. Generally, embodiments the present inventions relate to systems, equipment and processes using oxyfuel for high temperature processing of materials for the production of cements having a particle size distribution from about 0.1 μm to about 150 μm.

Disclosed is a method for manufacturing a hydraulic binder including a calcium aluminate, which involves: a) providing a composition including a lime C source compound and an alumina source compound, the composition including at most 95% lime C and alumina, and at least 23% alumina, by weight relative to the total weight of dry matter of the composition; b) placing the composition provided in step a) in a moisture-saturated environment, at a hydration temperature of between 40° C. and 150° C., so as to precipitate hydrated phases containing at least one aluminium oxide combined with a calcium oxide and with water; and c) subjecting the precipitates obtained in step b) to a baking temperature of between 200° C. and 1300° C., for at least 15 minutes.

Disclosed is a method for manufacturing a hydraulic binder including a calcium aluminate, which involves: a) providing a composition including a lime C source compound and an alumina source compound, the composition including at most 95% lime C and alumina, and at least 23% alumina, by weight relative to the total weight of dry matter of the composition; b) placing the composition provided in step a) in a moisture-saturated environment, at a hydration temperature of between 40° C. and 150° C., so as to precipitate hydrated phases containing at least one aluminium oxide combined with a calcium oxide and with water; and c) subjecting the precipitates obtained in step b) to a baking temperature of between 200° C. and 1300° C., for at least 15 minutes.

A cement production plant may include a preheater for preheating raw meal, a calciner for calcining the preheated raw meal, and a furnace with a furnace burner for firing the raw meal to form cement clinker. The furnace has a combustion gas inlet for admitting a combustion gas with an oxygen content of 30% to 75% into the furnace. The cement production plant may also include a cooler for cooling the cement clinker. The calciner and the furnace each have at least one respective fuel inlet for admitting at least one fuel into the calciner and the furnace. The calciner and the furnace each have at least one respective inert gas inlet for respectively admitting inert gas into the calciner and the furnace.

A method for the thermal treatment of clays by: preheating the clay, which is suspended in a carrier gas, in a heat exchanger; thermally treating the clay in a calcination stage operated under chemically oxidizing conditions; subsequently thermally treating the clay in a calcination stage operated under chemically reducing conditions; cooling the clay in a cooling stage operated under chemically reducing conditions; cooling the clay in a cooling stage operating under chemically oxidizing conditions.

Processes and plants for producing cement clinker, in which an oxygen-containing gas having a proportion of 15% by volume or less of nitrogen and a proportion of 50% by volume or more of oxygen is conveyed from a first section of the cooler directly adjoining the top of the furnace into the rotary furnace and is optionally additionally conveyed to the calciner, and where the total gas streams fed in to the combustion processes consist to an extent of more than 50% by volume (preferably more than 85% by volume) of oxygen.