Single and Two Stage Steam Jet Ejector

Single-stage steam jet ejectors operate on the Venturi principle. Steam expands through a nozzle, converting pressure energy into velocity energy. This high-velocity jet creates a vacuum and entrains air or gas, which then enters the converging section of the venturi. In the diffuser, velocity energy is reconverted into pressure, allowing discharge against a predetermined back pressure.

Single stage steam jet ejectors are used to create vacuum covering 40 mm Hg. Absolute.

Two Stage Ejector with Condenser : A two-stage ejector system consists of two units similar in construction to single-stage ejectors, with an inter-condenser (direct-contact or surface type) between them. In the first stage, steam expands through a nozzle, entrains gases, and discharges them into a diffuser at higher pressure. The discharge then enters the inter-condenser, where condensable vapors are reduced in volume. Remaining gases are handled by the second stage ejector, which further compresses and discharges them.

For proper operation: The ejector must be installed at sufficient height to allow barometric drainage of the condenser. If barometric installation is not feasible, an extraction pump is used to drain the condenser under vacuum. Final discharge (steam and gases) may be released to the atmosphere, condensed in an after-condenser, or directed to a water tank.
 
 Pressure Range of Two Stage Ejectors: Vacuum from 100 MM HG Absolute to 10 MM HG Absolute.