Air Ejectors
Air Ejectors are simple devices that operate on the basis of the jet Venturi principle. Typically Air Ejectors have 3 connections
- 1. Compressed Air Inlet
- 2. Suction
- 3. Outlet
During operation air ejectors are able to create a pressure differential across its suction and outlet openings. Air Ejectors utilize the energy in compressed air to create this pressure differential.
This enables air ejectors to be used for creating vacuum / low pressure at its suction. The low pressure allows the air ejector to suck air, gases, vapours, fumes, powders, dust, etc through its suction. The pressure of the sucked media increases inside the ejector and eventually it is discharged at a higher pressure from the outlet. The discharge contains the mixture of compressed air & the sucked gases and media.
This phenomenon allows the Air Ejector to be used for large variety of purposes such as compressing air & gases, inducing air & gas flows, vacuum creation, sucking and discharging vapours, fumes, powders, etc
The amount of gases sucked and pressure differential achieved depends upon the size of the Ejector and the internal construction.
Further the operating flows can be controlled by regulating the Compressed Air, Suction & Discharge Pressures.
Typical Applications
- 1 As Priming Ejector – for priming of Centrifugal pumps
- 2 As Sampling Ejector – for extracting samples from reactors
- 3 For generating process vacuum
- 4 As a Blower
Features of Air Ejectors
- Custom designed models – ensures perfect fit for your application.
- 2 Multiple Stages can be combined to create very deep vacuum.
- 3 Availability in multiple type of end connections – Flanged, Threaded, Hose
- 4 Available in a large variety of materials
| Metallic | Non Metallic |
|---|---|
| Carbon Steel | PP (Poly-propylene) |
| Stainless Steels SS 304 / SS 316 | PTFE (Poly-tetra-fluoro-ethylene) |
| Duplex & Super Duplex Stainless Steel | |
| Exotic metals (Hastelloy, Inconel, Titanium) |
Benefits of Air Ejectors
- 1 Static Device without any moving parts – ensure long reliability and maintenance free operation.
- 2 Use Compressed Air as energy input / fuel – Compressed air is readily available in most setups hence no additional infrastructure needed for operation.
- 3 Tolerate entry of liquids & solids particles into the ejector – avoids abrupt breakdowns.
- 4 Small & compact size – allows installation in tight spaces & difficult to access areas.
- 5 Non sparking operation – can be safely used in hazardous & flammable areas
- 6 Manufactured in multiple materials – allows using the most cost-effective & chemically compliant materials for the application.
Frequently asked questions (FAQs) about Air Ejectors:
An air ejector is a device used to convert pressure energy of a motive fluid (usually air) into kinetic energy to create a vacuum or low-pressure environment. It works on the principle of entraining and compressing a secondary fluid (typically gases or vapors) through the Venturi effect.
Air ejectors operate by directing a high-velocity stream of motive fluid (usually air) through a nozzle into a mixing chamber. This creates a low-pressure zone which draws in and entrains the secondary fluid (gas or vapor) through an inlet. The mixed fluid then passes through diffuser stages to recover pressure and decrease the velocity of the ejector discharge
Air ejectors are used in various industries such as chemical processing, pharmaceuticals, power generation, and oil refining. They are employed for creating vacuum in condensers, evaporators, distillation columns, and other process equipment where a reliable vacuum source is required.
Air ejectors are simple in construction, have no moving parts, and are capable of handling corrosive or dirty gases. They provide a continuous vacuum source without requiring lubrication or maintenance associated with mechanical vacuum pumps.
Air ejectors require a high-pressure motive fluid source (air), which can increase operational costs. They are also less efficient compared to mechanical vacuum pumps at achieving very high vacuum levels or handling large volumes of gas.
Sizing an air ejector involves determining the required motive fluid flow rate and pressure drop across the ejector to achieve the desired vacuum level and gas handling capacity. Factors such as inlet pressure, discharge pressure, and specific application requirements influence the sizing process.
Air ejectors typically require minimal maintenance since they have no moving parts. Periodic inspection and cleaning of nozzles, diffusers, and inlet filters may be necessary to ensure optimal performance and longevity.
Yes, air ejectors can vary in design based on their application requirements and the type of motive fluid used (usually air). Common variations include single-stage and multi-stage ejectors, which differ in the number of nozzle and diffuser stages used to achieve the desired vacuum level.
