Steam Ejector | Steam Jet Vacuum Unit

Home

Library

media

Steam Ejector (Gas Jet Vacuum Unit)

Product overview

Steam ejector is the core component and commonly used name for steam jet vacuum units and gas jet vacuum units in industrial sites. A single steam ejector can be used independently; a multi-stage steam ejector combined with a condenser forms a complete steam jet vacuum unit. The "steam ejectors" in this article refer to gas jet vacuum units and other related products provided by Chengdu Green Water Technology.

How steam ejectors work

Like other ejectors, steam ejectors are also jet devices that work based on the Venturi effect. It is the core product of the vacuum solution of Chengdu Green Water Technology Co., Ltd. It can be used alone or can be connected in multiple stages to form a steam jet vacuum unit to provide stable vacuum for distillation, drying, filtration, degassing and other processes.

During operation, motive steam passes through the expansion nozzle, converting pressure energy into kinetic energy and creating a vacuum, thereby injecting a mixture of air, process gas and steam into the Venturi diffuser. After momentum exchange, the kinetic energy of the motive steam is converted into the pressure energy of the mixed medium, and is discharged after reaching the predetermined back pressure.

Working process:
The steam converts pressure energy into velocity kinetic energy through the expansion nozzle, creates a vacuum, mixes the inhaled fluid, and then slows down the speed in the diffusion section and the pressure rises to overcome the outlet back pressure before being discharged.

Product picture

Basic structure of steam ejector

The steam ejector is the core unit of the steam jet vacuum unit (gas jet vacuum unit). Each steam ejector itself is a complete Venturi jet equipment, consisting of the following four key components:

Component	Function
Expansion nozzle	Motive steam enters and accelerates, converting pressure energy into kinetic energy, which is the source of energy to create vacuum
Suction chamber	The nozzle outlet forms a low-pressure zone that injects air, process gas or steam
Mixing chamber	The motive steam mixes with the ejected medium, and momentum exchange occurs
Diffusion section	The flow channel gradually expands, the mixed fluid decelerates and increases pressure, and is discharged after overcoming the outlet back pressure

Single unit and multi-stage configuration

1. Single unit: independently responsible for vacuuming, suitable for small occasions with low vacuum requirements.
2. Multi-stage series connection (condensing type): Multiple ejectors pump air step by step, and the intermediate condenser reduces the load of the next stage.
3. Multi-stage series connection (non-condensing type): direct series connection, suitable for small and low-consumption working conditions.

Material selection

Steam ejectors can be made of a variety of materials according to working conditions:

Material type	Typical materials	Applicable occasions
Metal material	Stainless steel, Monel, Hastelloy, titanium, bronze	High temperature, corrosive media
Non-metallic material	Graphite, polytetrafluoroethylene (PTFE)	Strong corrosion, special media

Application areas of steam ejectors

In addition to being used as vacuum pumps, steam ejectors have been widely used in industrial processes due to their characteristics of generating vacuum, ejection mixing, and boosted discharge:

Industry	Typical uses
Petrochemical industry	Crude oil vacuum distillation unit (VDU) pressure reduction system, vacuum distillation
Chemical industry	Reactor degassing, solvent recovery, vacuum drying
Electric power	Condenser vacuuming, geothermal power generation
Food/Pharmaceutical	Vacuum distillation, concentration, drying
Metallurgy	Vacuum degassing, VD/VOD auxiliary vacuum

FAQ

What is the difference between a steam ejector and a steam jet vacuum unit?

The steam ejector is a single jet vacuum equipment; the steam jet vacuum unit is a complete vacuum system composed of multiple steam ejectors and intermediate condensers connected in series. In engineering applications, "steam ejector" often refers to the entire unit system.

What is the relationship between steam ejector and gas jet vacuum unit?

Gas jet vacuum unit is a jet vacuum system that uses steam or other gases as the power medium. When steam is used as power, it is a steam jet vacuum unit, and the core equipment is a steam ejector.

How to choose condensing or non-condensing type?

For small units and situations with low power consumption, fewer stages can be considered, and even a condenser (non-condensing type) is not required. For high vacuum and large flow conditions, it is recommended to use a multi-stage condensing unit to reduce steam consumption and reduce equipment size.

Home

Products

Customer Sectors