Dense-phase pneumatic conveying systems are advanced systems that convey powder and granular materials through a pipeline at high material concentration, low velocity and in a controlled way. Compared with dilute-phase systems, the material is conveyed with much less air but at higher pressure.
Dense-phase conveying generally uses compressed air in the 1–4 bar range. Because the conveying velocity is low, wear on the pipeline and the conveyed product is kept to a minimum. This is a major advantage especially for fragile, abrasive, high-value or segregation-sensitive materials.
These systems are highly efficient for long-distance conveying and for applications that require transfer to several destinations. The product's particle size distribution is preserved during conveying, and dusting and product losses are significantly reduced.
Operating Principle
In dense-phase pneumatic conveying, the material is usually fed into a pressure vessel (transporter). Once the vessel is full, the inlet valve closes and air at an adjustable pressure is applied to the vessel. The outlet valve then opens and the material is sent through the pipeline to the destination silo, hopper or process. Conveying can work in batch or continuous mode.
Automation and Control
Dense-phase pneumatic systems run on a PLC-controlled automation infrastructure. Via the operator panel or SCADA system you can easily set and monitor:
• Conveying pressures
• Batch quantities
• Valve timings
• Auxiliary air lines
• Alarm and safety parameters
Using feedback from pressure, level and flow sensors, the system operates safely and stably.
Advantages
• Conveying over long distances
• Minimal wear thanks to low product velocity
• Less product segregation and breakage
• Low energy consumption
• Clean, environmentally friendly operation thanks to the closed system
• Ideal for abrasive and sensitive products
Applications
Dense-phase pneumatic conveying systems are widely used in many industries, especially cement, food, chemicals, plastics, energy, mining and building materials.