Eductors

Introduction
Eductor is a device which is used to create vacuum to suck the secondary liquid or gas. The main difference between Eductor and Ejector is that Eductor use water as motive fluid and Ejector use Air or Steam as motive fluid. There are some constructional differences, but the final duty is to create vacuum. Eductor is widely used in industries for number of applications.

Working Principles
Eductor operates in accordance with the well-known Bernoulli equation. A high pressure/low velocity motive fluid is converted into a lower pressure/higher velocity jet through a nozzle. Jetting past a suction connection in the head of the device will entrain a secondary low pressure fluid.

Eductor Sizing
Eductor diameter depends on the volumetric flow rate. The internals of Eductor such as jet nozzle sizing depends on requirement of suction. The other factors also have to be considered i.e. motive fluid pressure, pressure drop and requirement of downstream pressure.

Application of Eductors :

  • Emptying tanks, Sumps, Pumping and Mixing operation in Oil treating system.
  • Used as Vacuum Cleaner on Ships or in Industry.
  • Dewatering of Sand and Coal Barge.
  • Eductor can be used to agitate liquid and to mix two or more liquids intimately within a tank or other vessel without the use of baffles or moving parts inside the tank.
  • Eductor can be used for handling Slurries or dry solids in granular form.
  • Eductor can be used to mix two liquids intimately in various proportions in operations where the pressure liquid is the greater proportion of the mixture.

Advantages of Eductor:

  • Low Investment Cost.
  • Eductors are Self-Priming.
  • No Moving Parts.
  • Low Maintenance Cost.
  • Eductors can be used in hazardous condition.
  • Eductors can be made in any workable material which is corrosion and erosion resistant.
  • Easy and Simple Installation, Start-up and Operation.

Material of Construction:

  • Carbon Steel.
  • SS304/SS304L/SS316/SS316L.
  • Alloys.
  • Rubber lined/HDPE Lined.

Parts of Eductors:

  • Inlet Nozzle.
  • Suction Nozzle.
  • Internals (Eductor).
  • Pipe.
  • Outlet Nozzle.