An air-gravity conveyor is a gadget for moving a range of light-weight, fluidizable dry bulk powders. The conveyor consists of a rectangular chamber separated by an air-permeable, porous media. The media is put along a horizontal aircraft to separate two chambers within the conveyor: An upper chamber to handle the material being conveyed, and a lower chamber to deal with compressed air.
Air-gravity conveyors are usually made in 10 ft|3 m areas. Much shorter sections are utilized to comprise the precise required length of the overall conveyor.
When installed, an air-gravity conveyor is sloped somewhat downward-- usually at 6-- 8 ° from horizontal. A benefit to air-gravity conveying is that the length of an air-gravity conveyor is limited just by available headroom versus headroom needed to accommodate the system's slope. Hypothetically, an air-gravity conveyor can be considerably long-- if the required headroom is offered. In reality, air-gravity conveyors with lengths of 200-- 300 feet|61-- 91 m are not unusual.
How they Work
A positive fan or blower injects low pressure, dry air (usually 1 psig|0.7 bar) into the lower chamber. The air penetrates upward through the permeable media. When the air is counterbalanced by gravity, a conveyor uses physics similar to an air hockey table to fluidize/aerate materials as they stream downstream through the conveyor's upper chamber.
Air-gravity conveyors are utilized to manage a variety of dry, light-weight, easily fluidized powders, such as activated carbon, alumina, bentonite, calcium carbonate, cement, clays, cleaning agent powders, fly ash, gypsum, lime, pulverized ores, silica sand, soda ash, and talc, among others. To evaluate whether a powder is appropriate for air-gravity conveyance, a basic general rule is that the particle size is usually smaller than 50 mesh.
Industry Comparison: Air-Gravity Conveying Devices
Several devices manufacturers supply air-gravity conveyors; however, deficiencies may exist across item designs. Putting in the time to pre-qualify the style quality of an air-gravity conveyor will pay considerable dividends.
Financial Advantages of Air-Gravity Conveyors:
No moving parts (decrease wear, spare parts & lengthens life span).
Minimal maintenance requirements.
Low energy consumption (low-pressure air).
Needs a single power source (fan or blower).
No damage to product managed (decrease waste).
Increased conveying capabilities.
Ecological Benefits of Air-Gravity Conveyors:
Dust-tight to the atmosphere.
Low energy usage.
Low noise levels (fan or blower is remote from the conveyor).
Safety Benefits of Air-Gravity Conveyors:
No moving parts (lessens operator safety threats).
Low sound levels (fan or blower is remote from the conveyor).
Dust-tight to the atmosphere (prevent health & safety risks).
Air-Gravity Conveyor Considerations:
One should likewise recognize that with any type of conveying system, disadvantages may exist-- and air-gravity conveyors are no exception.
The following instances may develop obstruction within the system:
If the moisture material of the material dealt with is too high, the products might become too heavy to be properly fluidized.
If the air going into the lower chamber is too wet, it may integrate with the product being dealt with or create clogs in the media's pores.
Periodically, overnight temperature drops may produce condensation within the system. If a product is presented with this wetness present, obstructions may result.
If the installation angle of the conveyor is not high enough, blockages may result.
Turn Boxes: Utilized to divert item flow.
Side Discharges: Allow materials to be diverted toward other processes in between the start and end of an air-gravity conveyor.
Slide Gates or Drum Valves: Utilized to turn off and control product circulation through the upper chamber.
Dust Collection Vent: Mounted at the end of the conveyor to collect fugitive dust.
Bin or Filter: In order to convey products through an air-gravity conveyor, the air is introduced and included within the system. At some time, this air should be correctly vented through a bin or filter within the system.