Moving Food and Cereals with Pneumatic Conveyors
One of the best benefits of pneumatic conveyors is their
large powder handling capabilities. Pneumatic conveyors are able to move
surprisingly large and heavy materials from place to place. Many industries use
pneumatic conveyors, ranging from bulk material handling to the food industry.
The cereal industry uses pneumatic conveyors to move cereal
from an extruder to the packaging machine. Usually, this is done by generating
air pressure levels above or below the atmospheric pressure in the room. Most
cereal manufacturing companies either use dilute phase conveyors or dense phase
conveyors. Depending on the machine, the conveyors will use a pressure or
vacuum system to move the cereal from place to place.
Most factories use pneumatic conveyors for their flexibility
and their ability to move delicate materials without crushing the material and
wasting the cereal. Many conveyors can also reach multiple destinations at
While some companies object to the high power consumption of
pneumatic conveyors, the benefits typically outweigh the increased cost of
power. The power costs are higher, but the costs associated with product waste
and the improved efficiency of the process usually more than make up for any
extra costs- especially in larger factories.
The same pneumatic conveyors can also be used to move other
foods; it is not just for cereals. Many factories use pneumatic conveying
systems to move bulk materials such as flour, rice, or grains, as well as
lighter finished products in route to the packaging area.
Powder handling is the process of industrial mixing, conveying,
measuring or packaging of delicate, friable, sticky or free-flowing
powdered solids. Typically accomplished through pneumatic conveyors,
powder handling can also be done using closed or flexible screw
Pneumatic conveyors are particularly advantageous for powder handling applications as a result of their enclosed, tubular design, which reduces product leakage as well as eliminating material and operator contact. In addition, pneumatic conveyors offer decreased product contamination, which is a problem for screw conveyors since they are more susceptible to incur product damage by caking, smearing, packing or grinding. Common powdered solids that are handled using pneumatic conveyors include metals, chemicals, fly ash, flour and talc. As powder handling is most often used to move materials through manufacturing and processing stages, powder handling conveyors must be able to carefully and efficiently transport powders that could be potentially hazardous. Due to wide-ranging powder handling applications, diverse industries require powder handling conveyors including pharmaceutical, food and chemical processing, industrial, ceramics, plastics and construction. However, most pneumatic conveyors are designed to handle specific material types, so different industries will require a different type of conveyor. For powder handling applications, dilute phase pneumatic conveyors are the most common type of conveyors used. Dilute phase conveying can be done with either pressure or vacuum pneumatic systems, as long as high air velocity is created and maintained. Dilute phase conveying can utilize either positive or negative pressure, although each pressure type best works for certain applications. For example, positive-pressure dilute phase conveyors are best suited for conveying materials loaded from a single entry point to one or multiple destinations. Positive-pressure systems can transport materials over a relatively long-distance and use a minimum quantity of air to move the material. Conversely, negative-pressure dilute phase conveyors work best in transporting powdered materials loaded from numerous inlet points and discharging them at a single point. In addition, there are a variety of different dilute phase conveyor system designs. A closed-loop dilute phase conveyor uses an inert gas as the conveying medium to convey the powder in a closed-loop system. This type of dilute phase conveying is useful for handling hazardous powdered chemicals. A centrifugal blower dilute phase conveyor can use a combination of pressures or other system designs but use centrifugal blowers in place of positive displacement power packages.