Pneumatic Conveying System

Rajdeep’s specialized designs of Pneumatic Conveying systems for all dry material (Powder / Pallets).

Our pneumatic systems have high degree of flexibility, required low space & low maintenance & also weatherproof operation.

Rajdeep has large solid’s data bank & experience of number of installations and expertise in Pneumatic Conveying.

Rajdeep’s proven Capabilities in Conveying System:
  • Conveying Capacity up to 35 Ton Per Hour
  • Conveying Length up to 300 Mtr
  • Conveying solids BULK Density ranges from 150 – 2200 Kg/m3
  • Conveying with Close Loop System by conveying media Inert Gas (Nitrogen)
  • Solids conveyed like PTA powder, Polyester chips, LLDPE, ESP Dust, Talcum Powder, Grain Flour & many more.

A pneumatic conveying system is a process by which bulk material of almost any type are transferred or injected using a gas flow as the conveying medium from one or more sources to one or more destinations. Air is the most commonly used gas. For hygroscopic materials dry air can be used, and for potentially explosive materials an inert gas such as nitrogen can be employed.

Pneumatic conveying is more practical & economical method of transporting solid from one location to another than the mechanical conveying (Belt conveyor, Screw conveyor , vibrating conveying etc. ) because of following three reasons:-

  • These are totally enclosed and if required can operate without moving parts coming in to contact with the conveyed material.
  • Being enclosed very clean, environmentally acceptable & easy to maintain.
  • Very economical to install & operate
  • Very Flexible interms of routine & expansion
  • Can convey any product at any place.

Types of Pneumatic Conveying

1. Lean/ Dilute  Phase System
2. Dense Phase Conveying System


Dilute phase conveying occurs when a material is conveyed in suspension in the flowing air. The material is transported at high velocities through the system while being suspended in air. It is often referred to as suspension flow because the particles are held in suspension in the air as they are blown or sucked through the pipeline.

Dilute Phase is characterized by High velocity, low pressure & High solid to air ratio.


The dilute-phase system can be designed in three ways: 

  1. Positive pressure system
    Positive pressure systems operate above atmospheric pressure and are used to convey bulk materials from a single or multiple sources to one or multiple destinations, over medium distances and with greater capacity than possible using vacuum systems.
  2. Negative pressure or vacuum Conveying system
    Negative pressure conveying systems are those that operate with air pressures below atmospheric pressure.  Negative pressure (vacuum) is generally used to convey material from multiple sources such as storage vessels, process equipment, trucks and rail cars, to individual or multiple destinations.
  3. Combination of Positive – Negative System
    This combined positive –negative system incorporate the advantages of both negative and positive pressure arrangements in a single system. These systems are used where there are multiple material entry points, and multiple delivery points.
Salient Features:
  • Use low pressure, high volume gas & high velocity to transfer powder or granular bulk solids up to capacity 50TPH.
  • Solid to air ratio ( Kg solid / Kg air) less than 10
  • For lean phase pressure system conveying length is up to 300mt. approx.
  • For lean phase vacuum system conveying length is up to 50mt approx.
  • Systems use a positive displacement blower (Required press. < 1bar ) to develop the required motive force.
  • Rotary Valve or Ventury can be used as feeder in lean phase conveying system.
  • Lean phase systems are most used on those materials which are Non-abrasive, Non-fragile, Free flow and moisture content up to 10%.
  • Dust Free Operation

Dense phase conveying occurs when materials are conveyed with air velocities lower than those required for dilute phase over all or part of the pipeline.

Dense phase conveying is often referred to as non-suspension flow. In which the material is conveyed as the full bore plugs separated by air gaps.

Dense Phase is characterized by Low velocity, High pressure & low solid to air ratio.

Salient Features:
  • Use High pressure, Low volume gas & Low velocity to transfer powder or granular bulk solids.
  • Specially designed Pressure vessel with valves & air control is the key components of the system
  • Solid to air ratio ( Kg solid / Kg air) should be more than 10
  • For Dense phase pressure system conveying length can be more than 500 meter
  • This systems use Compressed Air / Gas to develop the required motive force.
  • Dense phase systems are most used on those material which are Abrasive, Fragile, High density
  • Dust Free operation
Various Equipments used in Pneumatic Conveying:
  1. Bag dump /Unloading Station.
  2. Roots Blower / Centrifugal Fan
  3. RAL (Rotary Air Lock Valve) / Venturi feeder
  4. Pressure Vessel & Control Instruments
  5. Product Separator / Vent Filter / Dust Collector
  6. Storage Silos/hoppers
  7. Special valves for diverting the flow/metering
  8. Control Panel
  9. Piping with special cross section bends
  10. Gas cooling Heat Exchanger for Close Loop Systems
  • Chemicals
  • Petrochemicals
  • Pharmaceutical
  • Distillery / Brewery
  • Paint & Pigment Handling
  • Food Industry
  • Power
  • Steel
  • Cement
  • Mineral Processing

For all type of powder handling.

Following table is self explanatory for the Selection of Dense or Lean Phase System.