High Capacity Conveying for Abrasive Ash

Fly ash generated by coal-fired, biomass-fired and industrial boiler systems is a demanding material to convey. Its fine particle size, abrasive mineral content, variable bulk density and temperature can place considerable stress on conventional pneumatic conveying systems, particularly over long distances and at high throughput. VOLDE develops fly ash conveying systems around dense-phase pneumatic transport, where the material moves through the pipeline at lower velocity and under controlled pressure. The objective is to reduce unnecessary wear, limit conveying-air demand and create a more stable transfer path from filters and collection points to storage silos or downstream handling areas.

| Dense Phase Conveying with DENSPLUS

Fly ash behaviour can vary considerably according to fuel type, combustion conditions and collection point. Particle size, bulk density, temperature and silica content all influence how the conveying system should be configured.

For this reason, DENSPLUS is selected and sized as part of the complete conveying calculation rather than as a standard pressure vessel. The system transfers ash in dense-phase flow, allowing higher solids loading at lower conveying velocities than conventional dilute-phase arrangements.

Key design parameters include:

• required conveying capacity and total route length
• horizontal and vertical sections together with bend geometry
• ash temperature, bulk density and abrasive character
• available conveying pressure and air supply

Pressure-vessel volume, pipeline diameter, filling and discharge cycles and operating pressure are then defined around these conditions.

For long-distance and high-capacity applications, this approach provides a strong basis for reducing line velocity and managing wear at critical points such as bends, risers and terminal sections.

| Flow Stabilization with

Dense-phase performance depends on maintaining the correct relationship between pressure, material loading and air distribution throughout the pipeline. On long routes, local pressure losses or changes in elevation can disturb the material flow and increase the risk of unstable conveying.

AIRPLUS support-air units are positioned along the pipeline where additional flow assistance is required. Rather than introducing large volumes of conveying air, they provide controlled local air injection to support the movement of the material through critical sections.

In practice, AIRPLUS can help:

• stabilize material movement along long horizontal and vertical sections
• moderate pressure variation at bends and elevation changes
• reduce excessive friction and local wear concentration

The number and position of AIRPLUS units are determined according to the route geometry and conveying calculation. In abrasive fly ash service, the combination of DENSPLUS dense-phase conveying and distributed support air allows the system to be engineered around lower velocity, controlled pressure and a more balanced flow profile.

| VOLDE Fly Ash Pneumatic Conveying

VOLDE Fly Ash Conveying Systems combine pressure-vessel technology, pipeline engineering and flow-support control to provide a robust conveying solution for power plants, waste-to-energy facilities and industrial boiler applications.