This vacuum technology uses the venturi effect
Piab
Vacuum conveying technology is widely used to provide gentle transport of dry bulk solids and powders in a range of applications. This firm offers a family of vacuum pumps and vacuum generators, based on patented, multistage Coax technology. The vacuum pump (photo) uses compressed air as the input, and through a venturi effect, is able to generate 22-in.-Hg vacuum, while driving air volumes (std. ft3/min) that are three times the volume of the compressed air inlet. Through the use of multiple stages, high vacuum is generated as the air flow is ramped up. This pump has no electric parts, which reduces maintenance and ensures long life and inherent safety in dusty or hazardous environments. — Piab USA, Hingham, Mass.
www.piab.com