Which pump requires air for operation?

The ejector pump operates by utilizing the energy from a high-pressure fluid, usually a liquid or gas, to create a vacuum that draws in and mixes with another fluid. This mechanism relies on the principle of jet propulsion, where the high-velocity fluid creates a low-pressure area that pulls in additional fluid. The need for air or a gas is crucial because it helps to create this vacuum effect, making the ejector pump particularly efficient in moving fluids, especially in applications like sewage treatment where air can facilitate the process of moving waste water or materials.

In contrast, other types of pumps, such as centrifugal, diaphragm, and gear pumps, function based on mechanical principles that do not require air for operation. Centrifugal pumps utilize rotational energy, diaphragm pumps employ a flexible diaphragm to create pressure changes, and gear pumps work by meshing gears to push fluid. These mechanisms do not rely on air or vacuum principles, making them distinct from the ejector pump's operational requirements.