An apparatus having various conduits moves liquid by passing gas up
through it. A collector conduit transports the liquid to the bottom of
the unit. A gas-lift conduit mixes the liquid and gas at the bottom and
transports the mixture upwards, owing to the rising action of the bubbles
and the resulting decreased density of the gas/liquid mixture. At the top
of the gas-lift conduit, some of the gas may escape from the liquid and
out of the apparatus. The lifted liquid may exit the apparatus at an
elevation higher than the entry point of the liquid or may be directed
down through a down and out conduit. A one way valve or equivalent
configuration may be used to limit flow to one direction.