Indirect Rotary Calciners

For processing at temperatures of up to approximately 2,000°F (1,093 °C). Pilot-scale equipment is available for temperatures of 2,300°F (1,260 °C).

An indirect rotary calciner can be supplied electrically heated or gas-fired. The furnace is usually arranged with multiple furnace zones. The furnace heats a rotating cylinder through which process material transports from the feed end to the discharge end.

Due to the indirect heating arrangement, the process material inside the cylinder is isolated from the heat source.  Consequently, the heat transfer is independent of the process atmosphere. This allows control of the process atmosphere with regard to volume and composition.

The indirectly heated calciner arrangement, therefore, is ideal for processing a wide-ranging particle size distribution, down to micron size materials, with a controlled temperature profile, retention time, and atmosphere.

Indirect Rotary Calciners from Thermal Processing Solutions are particularly suited to a variety of applications such as:

  • Processes requiring controlled oxidizing, reducing or inert atmospheres
  • Process materials requiring isolation
  • Processes with reaction kinetics improved by solid/solid or solid/gas contact
  • Processes that require deposition on a substrate
  • Materials with very fine particle size distributions
  • Materials that require controlled development of properties such as of surface area and porosity
  • Materials that benefit from a minimized process gas volume
  • Materials requiring exposure to a controlled, repeatable and uniform temperature profile
  • Materials that require a volatile component to be thermally desorbed from a substrate
  • Materials that are conduction heat transfer limited, and benefit from  dynamic exposure to a radiant heat source
  • Materials with fragile structures

The Indirectly Heated Rotary Calciner can be supplied pre-assembled on a mainframe, or as subassemblies for field erection. Process and power controls are supplied in pre-wired control panels, Controls can be supplied in pre-wired control panels, or a control P&ID drawing can be provided. The calciner is normally pre-piped, in the case of a gas-fired furnace,  or prewired, in the case of an electric furnace, with terminations located in an electrical marshaling panel. Interconnective wiring from the furnace to the control /power panel is by Others.