Lean Phase Pneumatic Conveying System
The Lean phase pneumatic conveying is a widely used method for transferring powders and
granules at high velocity using a continuous flow of air. It is ideal for applications
where material needs to be conveyed over long distances with consistent feed and minimal
interruption. In lean phase conveying, material is suspended in the air stream and
transported through pipelines at high velocity (typically 15–30 m/s). The system
operates under Positive Pressure (Blower) or Negative Pressure (Vacuum). The material is
fed into the pipeline via rotary airlock valves or venturi feeders and carried to the
destination through airflow.
Key Features
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Continuous conveying operation
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Suitable for long-distance transfer
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Flexible pipeline routing
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Low initial investment cost
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Easy automation and control
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Compact system design
Technical Specifications
| Parameter |
Specification |
| Conveying Velocity |
15–30 m/s |
| Pressure Range |
0.5 – 1 bar |
| Capacity |
Up to 50 TPH (depending on material) |
| Distance |
Up to 100 meters or more |
Comparison: Lean Phase vs. Dense Phase Conveying
| Parameter |
Lean Phase Conveying System |
Dense Phase Conveying System |
| Conveying Principle |
Material suspended in high-velocity air stream |
Material conveyed in plugs/slugs at low velocity |
| Air Velocity |
High (15–30 m/s) |
Low (2–10 m/s) |
| Pressure Range |
Low to medium (0.5–1.5 bar) |
Medium to high (1–6 bar) |
| Material Flow |
Dilute phase (air dominant) |
Dense phase (material dominant) |
| Power Consumption |
Higher |
Lower (more efficient for long distance) |
| Capacity |
Moderate to high |
Moderate to very high |
| System Complexity |
Simple |
More complex |
| Initial Cost |
Lower |
Higher |
| Maintenance Cost |
Moderate |
Lower over long term |
System Components
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Air blower / vacuum pump
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Feeding device (Rotary Airlock Valve /
Screw Feeder)
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Pipeline and bends
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Cyclone separator / Bag filter
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Control panel
Advantages
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Ideal for handling non-fragile
materials
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Quick material transfer with high
throughput
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Multiple pick-up and discharge points
possible
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Low maintenance with simple
components
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Dust-free and enclosed system
