Definition and characteristics of LECA
LECA, or lightweight expanded clay aggregate, is mainly made of natural clay, which is sintered in a rotary kiln to about 1200°C (2190°F), thereby expanding to form a nearly circular honeycomb structure.
Characteristics of LECA:
100% inert and can be reused many times.
Excellent sound and heat insulation performance.
Lightweight, porous, low density, high strength.
Natural, non-toxic, environmentally friendly green material.
Added to soil to increase insulation, the service life exceeds 100 years.
Neutral pH, fungus-free, frost-resistant, it is an ideal growth medium, topsoil and drainage system for plants.
Production process of LECA machine
The production process of LECA mainly includes steps such as raw material preparation, mixing, granulation, firing, cooling, screening and packaging. Among them, LECA machines play a key role in these steps:
Raw material preparation: The main raw material is clay or slurry, and sometimes other materials such as shale and slate are also used. These raw materials need to be pre-treated by crushing, screening, etc.
Mixing and granulation: The pre-treated raw materials are sent to the mixer for uniform mixing, and then formed into spherical particles by the granulator.
Firing: The spherical particles are sent to the rotary kiln for firing. During the firing process, the particles will expand to form LECA.
Cooling: After firing, LECA needs to be sent to the cooler for cooling.
Screening and packaging: The cooled LECA is screened, classified according to different particle sizes, and packed into different packaging bags.
Main equipment of LECA machine
The production line of LECA machine usually includes a series of main equipment, such as jaw crusher, ball mill, twin-shaft mixer, twin-roll granulator, rotary kiln, cooler, vibrating screen, etc. These equipment each play an important role in the production process of LECA:
Jaw crusher: used to crush the raw materials to achieve the appropriate particle size
Ball mill: used to further refine the particle size of raw materials and improve mixing uniformity.
Double-shaft mixer: to mix the raw materials evenly.
Double-roll granulator: to make spherical particles from the mixed raw materials.
Rotary kiln: used to burn spherical particles to expand them to form LECA.
Cooler: used to cool the fired LECA to prevent it from further expansion or deformation.
Drum screen: used to screen the cooled LECA and classify it according to different particle sizes.
