Lime calcining systems

Worldwide experience of limestone converting

Metso has supplied more than 210 lime calcining systems, over 115 of them as preheater/rotary kiln systems. The worldwide total annual production capacity from Metso supplied systems exceeds 30 million metric tons per year.

Worldwide presence

Our worldwide experience and expertise allow for local sourcing of major system components

Local support

With a presence in more than 50 countries, we remain close to our customers throughout the service life

Process expertise

Our CFD modeling provides process expertise and guidance for the best design for your plant

The Metso experience encompasses complete plant design including limestone crushing and screening, calcining (of both high calcium and dolomitic limestones), kiln firing, emissions, product handling and storage, and lime hydration.

APPLICATIONS

Agriculture
Soil stabilization
Building
Chemical and industrial purposes such as cement
Steel and alumina production
Water purification
As an alkali for many mineral and chemical processes

Lime calcining is the conversion of limestone (CaCO3) to lime (CaO).

Limestone is a sedimentary rock, the third most abundant mineral. Limestone is mostly quarried above ground; however, some underground limestone mining is done. Limestone is found with many different characteristics and different impurities.

The limestone characteristics change from different parts of the world and even different depths of mining. These characteristic differences are largely due to how it was formed. Limestone can be formed by chemically, organically, or clastic formation. Common impurities that can become a problem depending on the use or application are: SiO2 (Silica), Al2O3 (Aluminum Oxide), Fe2O3 (Iron Oxide).

The limestone must be tested to determine the appropriate technology for calcining.
Each lime kiln type and design is able to accommodate a given set of limestone characteristics. Testing to determine the suitability of a limestone for feed to a lime kiln is performed at Metso's Process Research & Test Center in Danville, Pennsylvania, USA using proprietary test procedures, referred to as a Limestone Evaluation (or LSE). Metso has established a reliable baseline against which to measure the suitability of a limestone for feed to a preheater-kiln system by evaluating nearly 1500 samples of limestone from around the world.