Venturi Ejector: An Overview and General Application Scenarios

A Venturi ejector, also often referred to as a Venturi vacuum pump or jet pump, is a fluid dynamic vacuum and conveying device with no moving parts. It primarily relies on the Venturi effect to perform functions such as gas suction, medium conveyance and mixing. Owing to its simple structure, no mechanical wear and strong adaptability, it is widely used in various fields including industrial production, environmental protection, chemical engineering and HVAC.

A Venturi ejector has no vulnerable mechanical components such as bearings and impellers, and does not require direct electric drive, as it is powered by the motive fluid. It boasts advantages including ultra-low maintenance costs, excellent sealing performance, temperature and corrosion resistance, and flexible start-stop operation. Its disadvantages are that the vacuum degree and pumping speed are greatly affected by the pressure and flow rate of the motive fluid. Compared with devices such as roots pumps and water ring pumps, a single-stage Venturi ejector offers limited improvement in vacuum degree, and multi-stage series connection is required for high vacuum requirements.

General Application Scenarios

The application of a Venturi ejector centers on three core functions: vacuum suction, fluid conveyance and medium mixing. It is suitable for various working conditions that require low-pressure suction, non-mechanical contact conveyance, or have on-site explosion-proof requirements or no access to electricity. Typical scenarios are as follows:

Vacuum Suction and Negative Pressure Generation: As its most core application scenario, it can replace traditional vacuum pumps to achieve negative pressure suction in various working conditions, such as vacuum feeding, vacuum suction and discharge, and surface adsorption fixation in industrial production.

Gas-Liquid Treatment in the Environmental Protection Field: With no risk of clogging and adaptability to impurity-containing media, it is widely used in the environmental protection industry, such as aeration mixing in sewage treatment, waste gas absorption and treatment, and rainwater and ponding suction.

Medium Conveyance and Mixing in the Chemical and Pharmaceutical Industries: It is suitable for the conveyance and mixing of corrosive, flammable, explosive and easily crystallizable media in the chemical and pharmaceutical industries. Without moving parts, it does not generate mechanical friction sparks, meeting explosion-proof requirements, and its smooth flow channel can reduce medium crystallization and clogging. It can be used to suction acid-base solutions and organic solvents, or realize the rapid mixing of two or more fluids; it can also be applied for vacuum degassing and evacuation in chemical reaction kettles to match the negative pressure reaction conditions of the kettles.

HVAC, Refrigeration and Industrial Auxiliary Applications: In HVAC systems, it is used for condensate drainage of central air conditioners; in the refrigeration industry, it cooperates with water chillers to realize the suction and circulation of refrigerants; in industrial auxiliary operations, it is used for equipment cooling and mold evacuation.

Mining, Metallurgy and Marine Industries: In mining, it is used for underground gas suction and water drainage; in the metallurgical industry, it suctions flue gas and dust generated during smelting and cooperates with dust removal systems to achieve gas-solid separation; in the marine industry, it is used for cabin ponding drainage and the suction and conveyance of fuel oil and lubricating oil, adapting to the bumpy working conditions of ships sailing at sea, and is more vibration-resistant due to the absence of mechanical parts.

Cleaning and Conveyance in the Food and Light Industries: In the food industry, it is used for the vacuum conveyance of food raw materials and vacuum degassing in food processing; in the light industry, it is used for negative pressure sewage suction for equipment cleaning.

Temporary Operations in Explosion-Proof, Non-Electric or Harsh Working Conditions: Powered by compressed air or steam without external electricity, it is particularly suitable for flammable and explosive sites, outdoor or temporary working conditions without power supply, as well as harsh working conditions with humidity, heavy dust and strong vibration.