Light Expanded Clay Aggregate Rotary Kiln is special calcination equipment for sintering expanded clay into Lightweight Expanded Clay Aggregate (LECA). During the calcination process, the temperature of LECA clay in the light expanded clay aggregate rotary kiln needs to be heated to about 1200 ℃ (2190 ℉).
Lightweight expanded clay aggregate rotary kilns can be produced in the desired LECA size and density. The particle size range of the expanded clay is between 100-200mm, and the particle size of the finished aggregate is generally 0-5mm, 5-15mm, and 15-25mm. The final finished lightweight expanded clay aggregate can be used to make lightweight concrete products and other applications.
Features of LECA Rotary Kiln
The production of lightweight expanded clay aggregates requires preheating and roasting in a double-tube plug-in rotary kiln. Double tube plug-in rotary kiln, also known as double tube rotary kiln, is a double tube structure rotary kiln formed by inserting a preheating and drying kiln tube and a roasting kiln tube. At the interface between the drying kiln cylinder and the roasting kiln, the small-diameter side cylinder is inserted into the large-diameter side cylinder to form a structure in which the inner cylinder and the outer cylinder support each other. The inclination angle of the rotary kiln is between 3.5% and 4%.
- LECA rotary kiln drive adopts frequency conversion speed regulation, which has high efficiency and low power consumption.
- Light expanded clay aggregate rotary kiln can support coal, natural gas, biomass fuel, etc.
- The LECA rotary kiln operates in a negative pressure mode, which produces less dust in the production process than other types of rotary kilns and is more environmentally friendly.
- The LECA rotary kiln has a simple technological process and can simultaneously complete the drying, granulation, and calcination of expanded clay aggregates.
Production Process of LECA in Light Expanded Clay Aggregate Rotary Kiln
The pre-treated cake-like clay raw material is fed into the drying kiln section, where it is transformed into pellets with good gradation. These pellets are dried and sent to the calcining section for sintering through a special conveying section.
During this period, the temperature of the LECA clay rotary kiln will be heated to about 1200°C. During heating, the gases produced to expand the clay through the thousands of small bubbles that form, creating a honeycomb structure. Due to the circular motion of the material in the rotary kiln tube, the resulting LECA is approximately circular or potato shape, and is available in different sizes and densities.
Technical Parameters of LECA Lightweight Aggregate Rotary Kiln
| Diameter(m) Preheating kiln | Diameter(m) Roasting kiln | Capacity(m³/h) | Inclination (%) | Rotate speed(r/min) Preheating kiln | Rotate speed(r/min) Roasting kiln | Calcination temperature(℃) |
|---|---|---|---|---|---|---|
| Φ1.25×18 | Φ1.6×14 | 2.21-2.96 | 3.5-4 | 1-5 | 1-5 | 1100-1200 |
| Φ1.55×20 | Φ1.9×16 | 3.27-4.36 | 3.5-4 | 1-5 | 1-5 | 1100-1200 |
| Φ1.8×22 | Φ2.2×18 | 4.42-5.9 | 3.5-4 | 1-5 | 1-5 | 1100-1200 |
| Φ2×24 | Φ2.5×20 | 5.57-7.41 | 3.5-4 | 1-3 | 1.2-3.6 | 1100-1200 |
| Φ3×20 Φ2.5×12 | Φ3×22 | 9.85-13.13 | 3.5-4 | 1-5 | 0.9-2.7 | 1100-1200 |
Application of LECA Clay
Lightweight expanded clay has many advantages such as lightweight, low thermal conductivity (as low as 0.097W/mK), good sound insulation, impermeability, non-decomposition under harsh conditions, fire resistance, freeze-thaw resistance, and lightweight backfill.
LECA clay aggregate is an increasingly popular building material and is widely used in the fabrication of lightweight concrete due to its low density and durability benefits to concrete products.
In addition to using clay to make lightweight expansive aggregates, fly ash, shale, pumice and slate can all be used to make ceramsite aggregates of different strength and density distributions suitable for different end uses.
LECA can also be used as backfill material for foundations, retaining walls, bridge abutments, and other structures, which can reduce earth pressure by 75% compared with traditional materials. Increase the stability of the foundation while reducing settlement and land deformation.
Lightweight expanded clay aggregate for plants. LECA performs well as a mulch in the cultivation of plants and shrubs.