What is a Pneumatic Conveying System?
A pneumatic conveying system is a setup that transfers dry bulk materials, including grains and powders, through an enclosed pipeline. Differential pressure and the flow of gas like nitrogen provides the necessary force for the transfer to occur.
Materials that are most effectively conveyed must be dry and they include cement, flour, sand, plastic pellets, chemicals, minerals, and even food products.
What Does a Pneumatic Conveying System Consist?
The complete system generally consists of an air mover like a blower, a feeder, a conveying line, a dust collector, and a vessel to collect the material at the endpoint.
Advantages of a Pneumatic Conveying System
Since it uses a small diameter pipeline to move material, the advantage of a pneumatic conveying system is that it can be constructed around existing equipment, taking up minimal space on its own.
The system also has few moving parts, making it relatively easy to maintain and diagnose when something goes wrong. It also offers less danger to the people operating the system as well as those who maintain it.
The material moves within an enclosed pipe. Thus, there is a minimal occurrence of dust and leakage of the material being moved, making it an overall clean process. There is also very little waste because there is minimal spillage.
The material moves very fast due to the fact that it is conveyed by air within the pipes.
They have an extremely low likelihood of contamination of the material being moved because it is done within an enclosed pipeline.
Because of the straightforward nature of the conveying system, it offers a flexible layout for the entire process.
Reservations with a Pneumatic Conveying System
While it is an overall effective solution for moving material, some things need to be kept in mind while installing a pneumatic conveying system as outlined below:
A pneumatic system requires a lot more horsepower to operate than a mechanical system because changing the air pressure to run the pneumatic conveying uses a massive amount of power.
Because a pneumatic system must separate the material conveyed from the conveying air at the end, a larger dust collection system is required than that of a mechanical conveying system.
It’s not possible to move some sticky materials like titanium dioxide and materials with large particles and high bulk density like rocks and gravel in a pneumatic conveyor.
It is not ideal for moving combustible bulk solids because they pose fire hazards when suspended in the air, so, precautions must be taken to ensure safety throughout the operation.
Components of a Pneumatic Conveying System
Pneumatic Conveyors are Composed of These Main Parts:
● Motorized compressors and fans at the beginning of the system, which generate the needed flow and pressure of air necessary to move material.
● Valves which prevent backflow of the compressed air in the system into the compressor area.
● Gauges and regulators to check the PSI of the air inside the compressor, which are connected and operated via computer.
● A feeder system that inserts the material to move into the conveyor without adding contaminants.
● Pipe which serves as the line through which material is conveyed to an endpoint.
● Buffer tanks and accumulators, which hold the compressed air and help to prevent irregular surges of airflow in the actuators, which are commonly cylinders and plungers.
● A material-gas separator to separate the solid material from the air and deposit into the silos.
● Lump-breakers, which break down the lumps formed in the material to facilitate a continuous flow through the system with no blockages or build-up.
● Storage units like silos, which hold the material that is being moved, throughout the process whereby the material is separated from the gas.
Pneumatic Accessories
Accessories are the parts that help to put together the conveyor system, and they include:
● Dump valves and terminal boxes, fitted at the very start of the conveyor system to form the termination of the transfer pipe.
● Dome and switch valves which enable the material to be routed to two or more final points.
● Tube valves, which divert the flow of material to many destinations where necessary.
● Density stabilizers which facilitate the conveying process by fluidizing the material being moved.
● Rotary vent valves, abrasive in nature, which are necessary when the product is being conveyed.
A pneumatic conveyor is an efficient solution for bulk material conveying from one point to another. It has many applications, and when utilized properly, it can introduce efficiency and convenience where there is material to move.
