A calcining kettle includes an outer kettle shell, an inner kettle shell, an interior heat exchanger assembly defining at least one tortuous path inside a volume defined by the inner kettle shell, and an agitator within the inner kettle shell. The inner kettle shell is disposed within the outer kettle shell such that the inner kettle shell and the outer kettle shell together at least partially define a jacket adjacent the inner kettle shell. The inner kettle shell and the interior heat exchanger assembly at least partially define a processing volume. The agitator is configured to rotate at least one paddle to cause movement of a feedstock material within the processing volume. A heating device may be structured and adapted to circulate a heat transfer fluid in the at least one tortuous path and the jacket. Calcining methods are also disclosed.

The present disclosure relates generally to processes for phase analysis of calcium sulfate materials useful in making gypsum products. In various aspects, the disclosure provides processes for providing a computer-implemented system for determining a phase content of a test calcium sulfate material; processes for determining the phase content of a test calcium sulfate material; processes for providing stucco feedstocks; and production processes for gypsum products.

A calcining kettle includes an outer kettle shell, an inner kettle shell, an interior heat exchanger assembly defining at least one tortuous path inside a volume defined by the inner kettle shell, and an agitator within the inner kettle shell. The inner kettle shell is disposed within the outer kettle shell such that the inner kettle shell and the outer kettle shell together at least partially define a jacket adjacent the inner kettle shell. The inner kettle shell and the interior heat exchanger assembly at least partially define a processing volume. The agitator is configured to rotate at least one paddle to cause movement of a feedstock material within the processing volume. A heating device may be structured and adapted to circulate a heat transfer fluid in the at least one tortuous path and the jacket. Calcining methods are also disclosed.

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.