Positive displacement (PD) blowers and vacuum pumps take advantage of positive displacement technology; which causes movement by trapping a fixed amount of air then forcing (displacing) that trapped volume into the discharge pipe. These pumps can be further classified depending on what type of mechanism is used to move the air.
Positive displacement blowers usually come in either bi-lobe or tri-lobe configurations. Bi-lobe blowers and vacuum pumps have been around for a long time and are used in a wide variety of applications because of their durability and flexibility. Tri-lobe blowers usually can operate with higher throughput than the standard bi-lobe units. Tri-lobe blowers often operate with less noise and pulsation levels as well. Another design configuration available to both bi-lobe and tri-lobe blowers is a helical lobe design which can allow for even more noise and pulsation reduction.
Yet another more recent improvement is the helical screw blower which offers reduced energy consumption compared to traditional lobe blowers as well as eliminating the pulsation that standard lobe blowers create. Helical screw blowers can reach higher pressures than lobe blowers, but can’t produce the higher flow rates that lobe blowers are known for.
In general, positive displacement blowers are most effective with high volumes at low vacuums and pressures. Choosing the right blower is critical to maximizing productivity and ROI. There are so many different variables that need to be addressed that it is hard to tag a specific style blower to a specific application. A general overview of applications in which you would find PD blowers being used can be found below:
|Aquaculture – Aeration||Oil & Gas – Gas Collection & Sparging|
|Cement – Fluidization & Conveying||Fly Ash Conveying|
|Chemical – Vacuum Processing & Conveying||Gas Boosting|
|Coal /Landfill – Methane Gas Recovery||Chip Conveying|
|Dairy – Automated Milking||Processing & Conveying|
|Dry Bulk Handling – Trailer Unloading||Potholing & Slurry Recovery|
|Vacuum Extraction & Sparging||Environmental – Sewer Cleaning|
|Industrial – Material Vacuuming||Aeration & Backwashing|