Airlift pump

The pump injects compressed air at the bottom of the discharge pipe which is immersed in the liquid.

Other applications include dredging, underwater archaeology, salvage operations and collection of scientific specimens.

By buoyancy the air, which has a lower density than the liquid, rises quickly.

The first airlift pump is considered to be invented by the German engineer Carl Emanuel Löscher [de] in 1797.

It arranges to store up the air, and release it in large bubbles that seal to the lift pipe, raising slugs of fluid.

Diagram of an airlift pump
An airlift pump, powered by compressed air, raises fluid by entraining gas to reduce its density.
1. air supply
2. liquid supply
3. air inlet port
4. air supply line
5. air port
6. air outlet
7. fluid intake
8. riser tube
9. air liquid mixture
10. pump outlet
L: liquid, usually wastewater
LL: liquid level
V: Vessel
G: Gravel or solids.
Movement of the liquide by injection of compressed air for micro-organism cultivation in the CiYOU, bioreactor from Biorea
Diagram of a geyser pump
A geyser pump, an improved airlift pump, powered by compressed air, raises fluid by forcing rising bubbles to displace fluid.
50. air supply
52. air inlet port
58. liquid supply
60,62. air supply lines
64. upper end of air tank 86
66,82. air ports
70. upper air inlet of u-shaped elbow 74
76 air outlet
84. fluid intake
65. riser tube
88. displaced liquid
90. pump outlet
L: liquid, usually wastewater
LL: liquid level
VVV: vessel
G: gravel or solids
Airlift pump (left) compared to geyser pump (right)