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.

Multi-burner apparatus for calcining gypsum. In accordance with an implementation, an apparatus for calcining gypsum includes a housing and pair of burner assemblies positioned within the housing. Each burner assembly includes a burner, a fluidization plenum, an agitation frame positioned over the fluidization plenum, and a serpentine burner conduit extending through the housing between the burner and the fluidization plenum. The fluidization plenums of the burner assemblies are spaced from one another.

An apparatus for calcining gypsum includes a housing, at least one burner assembly, and at least one baffle. The housing has opposite first and second lateral walls, an inlet, and an outlet. The at least one burner assembly is connected to the housing, and can include a burner, a fluidization plenum, and a serpentine burner conduit. The serpentine burner conduit at least partly extends through the housing and to the fluidization plenum. The at least one baffle is disposed in the housing and attached to one of the first and second lateral walls. The baffle extends at least partly across the housing toward the other of the first and second lateral walls to define a flow path for the gypsum. The flow path extends from the inlet, around the baffle, and to the outlet.

An apparatus for calcining gypsum includes a housing, at least one burner assembly, and at least one baffle. The housing has opposite first and second lateral walls, an inlet, and an outlet. The at least one burner assembly is connected to the housing, and can include a burner, a fluidization plenum, and a serpentine burner conduit. The serpentine burner conduit at least partly extends through the housing and to the fluidization plenum. The at least one baffle is disposed in the housing and attached to one of the first and second lateral walls. The baffle extends at least partly across the housing toward the other of the first and second lateral walls to define a flow path for the gypsum. The flow path extends from the inlet, around the baffle, and to the outlet.

A process for the calcination of raw gypsum in a heatable extruder, wherein the raw gypsum is feed into the extruder and heated to a temperature of from 150 C. to 350 C. to thereby convert the raw gypsum to calcined gypsum with a content of calcium hemihydrate of at least 50 wt.-%. By using a heatable extruder for the calcination, calcined gypsum with a high content of calcium sulphate hemihydrate and low residual amounts of the respective dihydrate and anhydrite can be obtained. The present invention further concerns a system, which is adapted to such preparation of calcined gypsum and includes an appropriate heatable extruder and the use of a heatable extruder for the calcination of raw gypsum.

A process for the calcination of raw gypsum in a heatable extruder, wherein the raw gypsum is feed into the extruder and heated to a temperature of from 150 C. to 350 C. to thereby convert the raw gypsum to calcined gypsum with a content of calcium hemihydrate of at least 50 wt.-%. By using a heatable extruder for the calcination, calcined gypsum with a high content of calcium sulphate hemihydrate and low residual amounts of the respective dihydrate and anhydrite can be obtained. The present invention further concerns a system, which is adapted to such preparation of calcined gypsum and includes an appropriate heatable extruder and the use of a heatable extruder for the calcination of raw gypsum.

An extruder, preferably for calcining and extruding raw gypsum, including a calcination zone and a mixing zone, wherein the extruder is optionally configured to capture and/or retain water liberated in the calcination zone, apparatuses and processes employing such extruders and respective uses.

An extruder, preferably for calcining and extruding raw gypsum, including a calcination zone and a mixing zone, wherein the extruder is optionally configured to capture and/or retain water liberated in the calcination zone, apparatuses and processes employing such extruders and respective uses.