How does a pneumatic conveyor work?

A pneumatic conveyor moves materials in a closed pipeline using compressed air. The system relies on the attractive force created by the airflow to transport powders, granules and other bulk materials efficiently and dust-free. Pneumatic conveying is particularly suited to situations where flexible material transport over long distances or through complex routes is required. This technology offers significant advantages over traditional mechanical transport methods.

What is a pneumatic conveyor and how does it differ from other transport methods?

Pneumatic conveyor use compressed air or other gas for the transfer of materials in a closed pipeline. Unlike mechanical conveyors, where the material is moved by conveyor belts or screws, the pneumatic system creates an air flow that carries the particles along.

The fundamental difference with mechanical systems is that pneumatic transport does not require moving parts in contact with the material. Piping can be designed to traverse differences in height, bends and confined spaces with ease. Mechanical conveyors, on the other hand, require straight or limited bending paths.

Pneumatic material handling is particularly suitable for fine and medium bulk materials. The system can be implemented either as diluted phase transport, where the material travels at high air velocity, or as dense phase transport, where a lower velocity and a larger volume of material is used in the pipeline.

How does a pneumatic conveyor move materials in practice?

The pneumatic transport operational process begins by creating an air flow by means of a compressor or fan. The material is fed into the system via a feeder, where it mixes with the air flow to form a mixture to be conveyed.

Transport takes place in a closed pipeline, where the material is carried by an air flow towards its destination. The design of the pipeline is critical: the diameter, material and route of the pipe all affect the efficiency of the transport. Air velocity and pressure are adjusted according to the characteristics of the material being transported.

At the site, the material is separated from the air by a separator, typically a cyclone or filter. The clean air is recirculated back into the system or out, while the material is collected in a receiving tank. If required, the system can be equipped with additional components such as air filters and automatic control devices to optimise industrial transport.

What are the main advantages of pneumatic transport in industry?

The main advantage of pneumatic transport is its flexibility and purity. The closed system prevents the spread of dust into the working environment and protects the material from external contaminants. This is particularly important in the chemical and process industries, where cleanliness requirements are high.

Energy efficiency is significantly improved when the system is designed correctly. Dense phase pneumatic transport uses less energy than conventional methods because the material moves at a lower air speed. Maintenance needs are reduced as there are fewer moving parts and less wear and tear.

Environmental friendliness is highlighted through reduced energy consumption and material waste. The pneumatic system can be fully automated, improving process accuracy and reducing human error. Bulk material handling is safer as workers do not have to come into direct contact with the material being handled.

For which applications is a pneumatic conveyor best suited?

Pneumatic transport works optimally powdered and granular materials for the transfer of particles with a particle size of less than 20 mm. The most suitable materials are light to medium weight and do not tend to stick together.

Distances can vary from a few metres to several kilometres, depending on the type of system and material. Capacities range from a few kilograms to thousands of tonnes per hour. Conditions can be demanding: the system can operate in high temperatures, humidity and even in explosive environments in compliance with ATEX requirements.

Pneumatic transport is not the best option for very heavy materials, such as metal powder, or materials that are sensitive to abrasion by airflow. Also, very wet or sticky materials can pose challenges in the form of pipeline blockages. In these situations, mechanical material transfer solutions may be more appropriate.