Embodiments of a system and a method for manufacturing calcined gypsum can include a calcination unit having a heating unit with at least one variable heater and a calciner temperature control device having a temperature sensor and a controller in operable arrangement with the temperature sensor and the heating unit. The calciner temperature control device is configured to adjust a thermal energy output rate of the heating unit based upon a comparison of the detected temperature and a target set point temperature so as to allow the supply of gypsum to be fed into the calcining chamber at a constant rate.

A plant for heat treatment of mineral material comprises a reactor having at least one gas inlet for admitting offgases, wherein the reactor comprises an activating region for activating the mineral material and an offgas outlet for ejecting offgases from the reactor, wherein the offgas outlet is connected to the at least one gas inlet in such a way that at least a portion of the offgas is supplied to the reactor. A process for heat treatment of mineral material with a reactor, comprises activating the material in an activating region of the reactor and optionally cooling the material in a cooling region of the reactor, wherein the offgas of the reactor is discharged therefrom, wherein at least a portion of the offgas discharged from the reactor is returned to the reactor.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods makes use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods makes use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.

A calcination and cement production apparatus comprising a calciner configured to be heated by combustion of a carbon based fuel and a hydrogen peroxide oxidant composition is disclosed.

Systems and methods for beneficiating a recovered fly ash material and/or recovering fly ash from an impound site are described. The method may include thermally treating a first portion of a recovered fly ash material to form a thermally treated fly ash having a first temperature of at least 1000 F., and contacting the thermally treated fly ash with a second portion of the recovered fly ash material to cool the thermally treated fly ash to a second temperature of less than or equal to 500 F. and form a fly ash product. The fly ash product may have a carbon content less than 8% by weight, based on the total dry weight of the fly ash product.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods makes use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods makes use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.

A method for producing burnt end products from an educt (starting raw materials) of carbonate-containing materials involves preheating the educt using heat recovered from the reaction. The educt and a fluidizing medium including steam are input into a first reaction zone. Heat is transferred to the first reaction zone using mechanical components so as to heat the first reaction zone to a predetermined temperature range for a predetermined time period. The educt is burned in the first reaction zone over the predetermined time period during which the first reaction zone is maintained within the predetermined temperature range. The hot gases that form in the first reaction zone include CO.sub.2 and steam. Hot end product is discharged from the first reaction zone after the predetermined time period elapses. Heat contained in the hot gases and end product that are discharged from the first reaction zone is used to preheat the educt.

A method for producing burnt end products from an educt (starting raw materials) of carbonate-containing materials involves preheating the educt using heat recovered from the reaction. The educt and a fluidizing medium including steam are input into a first reaction zone. Heat is transferred to the first reaction zone using mechanical components so as to heat the first reaction zone to a predetermined temperature range for a predetermined time period. The educt is burned in the first reaction zone over the predetermined time period during which the first reaction zone is maintained within the predetermined temperature range. The hot gases that form in the first reaction zone include CO.sub.2 and steam. Hot end product is discharged from the first reaction zone after the predetermined time period elapses. Heat contained in the hot gases and end product that are discharged from the first reaction zone is used to preheat the educt.