Dense Phase Pressure Conveying
Dense Phase Pressure Conveying Systems generally use compressed air at above 1 Bar g to push materials from a Pressure Vessel (also known as a sender unit or pressure pot) through a pipeline to the destination where the air and product are separated by a filter or other system.
The product extrudes through the pipeline, initially at low velocity, and gradually accelerating towards the destination. Systems generally operate on a batch basis as follows: (simplified)
| Step 1 |
Fill the sender unit with product to be conveyed |
| Step 2 |
Pressurise with compressed air. |
| Step 3 |
Open discharge valve until the product has been conveyed out. |
| Step 4 |
Close discharge valve and refill vessel. |
A panel of valves and sensors are used to control the air pressures and velocities at all parts of the system to ensure smooth reliable conveying of the product.
Applications
Dense Phase Pressure Conveying Systems are particularly suitable for systems, which convey materials at high capacities over long distances, to multiple destinations. Most systems include several air control valves and the high 
pressure compressed air supply is able to overcome the pressure drop generated by the most difficult materials, while also providing controlled conveying for friable materials. The lower convey velocities also extend the service life for systems conveying abrasive materials.
Specifications
| Convey Rates |
High, up to 100 tonnes/hr or higher |
| Convey Velocities |
Low, 1-10 m/s |
| Convey Distances |
High, up to 500m or longer |
| Air Mover |
Compressor (Screw, rotary, reciprocating) |
| Operating Pressure |
Up to 8 Bar g |
| Material/Air Ratios |
high, up to 150 kg/kg |
| Note All values approximate, refer Nu-Con for advice about how to convey your product. |
Options
To optimise the system various techniques are used to reduce compressed air consumption and cost, and additional options for specialised applications are available:
|
Air injectors to fluidise materials to reduce friction
Pulsed air injection to break up the product flow into discrete slugs
Line Boosters to assist conveying along convey route
Vibration to loosen cohesive powders prior to conveying
Twin vessels to provide continuous conveying
In-Line sifting, sampling, delumping, metal detection and magnetic separation systems
Stepped convey lines to reduce terminal velocities, abrasion and degradation
Stainless Steel construction for sanitation or corrosion resistance
Demountable and polished designs to USDA 3A standards for ease of cleaning |