Pneumatic Conveying

Pneumatic
Conveying

The art of transporting
material inside
a pipe

Pneumatic conveying can be defined as the art of transporting dusty or granular material within a pipeline using the flow of air through it.

The pressure difference at the ends of the pipe allows for a flow of air which, if it reaches and maintains the right velocity, is able to transport the product to its intended destination.

Pressure and velocity are the main parameters characterising pneumatic conveying, but there are many others, some related to the properties of the conveying fluid, others, and they are the majority, intrinsically linked to the product to be handled. Weight, shape, moisture, permeability, propensity to fluidise or aggregate are just some of the many elements that come into play when discussing pneumatic transport.

Since the early decades of the 20th century, i.e. when pneumatic technology began to be used to handle bulk material, much effort has been put into creating a mathematical model capable of describing its dynamics, but despite everything, there are too many variables at play and pneumatic conveying, although widely used in modern industrial reality, remains essentially an art.

In order to realise an efficient system, it is necessary to turn to specialists in the sector, those who have gained experience and specific knowledge in the transport of the product to be handled. Above all, it is necessary to turn to companies that have test facilities that are able to test and measure the product’s behaviour concretely and in advance, thus avoiding sizing errors and unpleasant surprises after the system has been built.

Types of pneumatic conveying

Pneumatic conveying is a widely used system for handling powders and granules. Thanks to the flexibility of this system, it is possible to transfer material inside pipes without the need for heavy support structures. They are easy to maintain and being closed systems, they are clean systems: the products transported are not contaminated from outside and do not disperse dust into the environment. For these reasons, there are applications in almost every industrial sector, from the chemical industry to the food industry, from pharmaceuticals to the plastics processing industry, etc.

Pneumatic conveying systems can be classified according to their construction characteristics.

“VACUUM SYSTEM”
NEGATIVE PRESSURES

“PRESSURE SYSTEM”
POSITIVE PRESSURES

Or depending on the mixture ratio, i.e. the concentration
of product in the pipeline during transport: