Lean phase conveying, also known as dilute phase conveying, is a widely used pneumatic transport method for bulk solids across various industries. Let’s explore its key features:

1. Dilute Phase Operation:
   • In lean phase conveying, the air quantity significantly exceeds the material quantity. This results in a dilute phase where the material is suspended in a high-velocity air stream1.
   • The minimal material-to-air ratio ensures efficient transport.
2. Advantages:
   • Suitable for short distances within a plant.
   • Handles a variety of particle sizes, shapes, and bulk densities.
   • Dust-free operation with minimal spillage.
   • Flexibility in routing—both vertical and horizontal transport.
3. Types of Lean/Dilute Phase Systems:
   • Positive Pressure Conveying:
     • Operates above atmospheric pressure.
     • Suitable for medium distances and higher capacity.
     • Enables multiple destination deliveries using diverter valves.
   • Negative Pressure Conveying (Vacuum):
     • Operates below atmospheric pressure.
     • Material is sucked into the air stream using a vacuum.
     • Minimizes dust injection into the atmosphere.
4. Applications:
   • Lime
   • Hydrated Alumina
   • Calcium Carbonate
   • Pulverized coal dust

Lean phase conveying systems offer efficient, reliable material handling, making them a valuable choice for industrial processes.