Innovation - engineering - processes

Calcination definition

Controlled thermal treatment of inorganic materials

Calcination is a thermal treatment process most commonly applied to inorganic products. In its most conventional meaning, the term “calcination” is widely used in industrial thermal processing terminology to describe the processes of burning the lime or converting the iron ores into oxides. In the modern technologies, the definition has been widened and calcination is often used to describe a variety of process of decomposition through heating in controlled atmospheres: both oxidizing and inert, performed to achieve a certain degree of material transformation, without its reaching its melting or fusing point.

Today, most common examples of commercial calcination processes using high temperatures include operations of chalk or limestone conversion to lime, dehydration of minerals, activation of carbon, catalyst regeneration, driving off the carbon dioxide, as well as treatment eliminating the undesired compounds like volatiles or organics.

calcination conveyor - Spirajoule

Our approach: Focus on the precision

Our equipment is a continuous system based on electrically heated screw conveyor, that allows to carry this process in precise, controllable and efficient way. Thanks to its unique features, Spirajoule converts powders, minerals and other inorganic materials into high purity products.

Whether it is calcination, dehydration, or volatiles removal – the key to efficient product treatment is a controllable, high stability reactor treats the material in continuous and efficient manner.

We ensure it thanks to electrically heated screw conveyor (Spirajoule) – a direct heating device that precisely heats and converts bulk powders, while allowing to avoid the dust and air emission challenges linked to the traditional calcination processes done in kilns based on fossil fuels.

A new approach to minerals processing and calcination technology

Conventional approach to the calcination process base on using directly or indirectly fired calciners consuming large amounts of fossil fuels to achieve the desired reaction temperatures. In the same time, the progress of energy transition, increasing cost of carbon emissions and growing availability of renewable electricity is placing the fossil-based processes under careful examination and changing the approach towards industrial heat treatment worldwide.

As a response to the growing demand of industrial calcination technologies capable to deliver high-temperature heat basing only on renewable sources, we propose a Spirajoule electrically heated screw conveyor, which represents a new approach towards the mineral processing technologies.

  • Fossil-fuels free. Powered by electricity.  Process heats materials only by electricity, which makes it free of difficulties related to burning conventional, fossil fuels and off-gases generation. System is adapted to be powered exclusively from clean, carbon-free sources if needed.
  • Precise and adaptable treatment. Our calcination kiln bases on patented, hollow shaft electrically powered screw. Processed bulk product and powders, after entering the oven are conveyed along the reactor. The screw as a heater makes the powders consistently affected by temperature. Conditions of treatment are monitored and fully adaptable by the operator. Thanks to the stable, electrical power supply, process is precisely maintained and ensures the uniform treatment.
  • Temperature adjustment up to demand. Spirajoule® is equipment suitable for calcination and mineral treatment performed in temperatures up to 850 degrees C. Solution offers easy adjustment of operating parameters allows to setup optimum treatment conditions and meet the performances and qualities for your individual product.
  • Direct heat exchange. The screw conveyor is a heating measure itself. Thanks to remaining in continuous, direct contact with the treated calcium powders, it ensures the high level of treatment consistency and efficient heat exchange.
  • Continuous process. The Spirajoule® reactor is made to be a heart of a chemical process, where the raw materials are converted into the products. We propose a continuous processes where the reactants are fed to the unit and the products withdrawn continuously while reactor operates under steady-state conditions. Continuous calcination process allows lowering the costs and remains a good match for industrial applications.
Heat treatment and calcination principle
Spirajoule minerals processing plant

Simple solution for minerals processing on site

Compact, space-saving design. Our technology is fully modular and can be delivered in containerised modules corresponding to size of ISO containers, that allow quick implementation of your mineral treatment and calcination plant.

Modular units. Technology is based on combination of modules or skids (capacity 20 to 36 tpd), that can be independently delivered and operated, allowing a high operation flexibility as well as efficient scale-up of plant together with the demand.