Key Benefits

  • Recyclable fuel system
  • Reduced waste gas
  • Reusable evaporated acid
  • Minimal maintenance

An indirect rotary kiln that keeps sustainability in mind without substituting quality

With a strong demand for the mining industry to adopt a more sustainable method of producing high-quality products, the machinery used must be designed to accommodate this need, while still maintaining a high level of efficiency and productivity. However, if designed poorly, maintenance issues and higher operational costs can make this sustainable approach not worthwhile. 

This is why, at FLSmidth, we have designed and engineered an Indirect Rotary Kiln that aims to provide a solution to these problems. Rather than applying heat directly to the material – as direct rotary kilns do – the Indirect Rotary Kiln is heated from the outside, where the material is heated via contact with the outer kiln shell. This allows for a more tightly controlled environment, which is especially effective when used primarily in the lithium from spodumene industry. The kiln is also suitable for use with any minerals bearing ore from which the action of mineral acids extracts metals.

For this reason, we have manufactured our indirect rotary kilns to be highly robust, ensuring minimal maintenance and a longer service life. With our kiln, you also benefit from reduced fuel consumption and waste gas emissions, which is both cost-effective and sustainable.

For these reasons, our indirectly heated rotary kiln is the best of its kind, making this product your ideal choice when you need high-quality material processing at your facility.

Benefits that reduce operating costs and maintenance

FLSmidth’s Indirect Rotary Kiln offers numerous benefits designed to optimise your facility while reducing operating costs and maintenance.

Recyclable fuel system
Our Indirect Rotary Kiln has been designed to reduce fuel consumption, as it recycles combustion gas, thus improving heat recovery. This offers you a more sustainable method of processing materials while also reducing operational costs. 
Reduced waste gas
The method used by this Indirect Rotary Kiln reduces the need to treat waste gases, as the combustion gases do not dilute the gases emitted from the processed ore. This helps to reduce operation times, allowing you to complete the process at a faster rate.
Reusable evaporated acid
We have ensured that any evaporated acids produced during the acid roasting process can be collected and reused in upstream ore processes. This will help to reduce operational costs further.
Minimal maintenance
With our desire to reduce maintenance, we have ensured that the Indirect Rotary Kiln comes with an automatic lubrication system, designed to allow for the continuous movement of the rotating parts. As it also comes with a highly robust outer shell, our equipment offers the most extended service life possible.

Features that promise efficiency and versatility

The wide range of features available with our Indirectly Heated Rotary Kiln allows you to conduct material processing more efficiently at your facility.

Safety features

Our Indirect Rotary Kiln comes with many safety features, including:

  • Sealing around the outer shell to prevent dust and gaseous emissions escaping into the atmosphere
  • Insulated enclosing of the exposed rotary kiln shell and the heater box assembly to prevent burns or heat-related injuries
  • Fully enclosed guards around all pinch-points to prevent injury
  • Built-in gas analysers for the safe combustion of fuels
  • Separate handling and treating of exhaust gases to reduce gas and dust emissions


Versatile kiln options

FLSmidth offers you both gaseous fuel combustion and electrically heated kilns, allowing you to decide which type of kiln best suits your needs.


Durable shell

The kiln’s robust rotating shell allows for both an extended service life and the flexibility to process a large variety of materials.


Insulated refractory lining

Our Indirect Rotary Kiln has been designed with a two to three-component insulated refractory lining in the heater box assembly, which helps keep heat loss to a minimum.


Reduced number of fuel burners

Our Indirect Rotary Kiln has fewer fuel burners, which reduces the size of the kiln, allowing it to fit more effectively into smaller facilities. 


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