Venturi Gas Scrubber

Gas cleaning, odour control and partical removal

Venturi Gas Scrubbers

The use of wet scrubbers for control of air pollution has gained wide acceptance through out industry. Gas scrubbers are very effective at removing noxious gases, particles, odours, fumes and dust from gas streams. Particulate contaminants are removed by impaction with a high velocity spray, where as gases and odours are eliminated through absorption or chemical reaction between the gases and scrubbing liquid.

In addition to being highly effective air pollution control devices, wet scrubbers like these are also used in process operations where:

  • Gases must be cleaned and cooled for further use
  • Gases must he absorbed in to liquids
  • A chemical reaction is required between liquid and gas
  • Valuable solids must be recovered from a gas stream

No other form of gas scrubbing equipment offers the unique combination of attributes obtainable with ejector-venturi systems. From the stand point of technology and design, ejectors demand the type of knowledge that can be acquired only by long experience and years of testing and recording data. And from an end user standpoint we have the stark simplicity of unit construction and the ease of operation. Venturi Scrubbers also require minimum supervision and maintenance, which combined with the below advantages make this type pollution control system ideal for most purposes.

  • Efficiencies to 98% with single stage systems and to 99.8% with multi-stage systems
  • Except for the liquid pump and motor, there are no moving parts to adjust or repair, no packing glands to maintain, and no parts to require lubrication
  • Reliability is built in as a result of uncomplicated & robust construction
  • Supervision and maintenance are held to a minimum. There are no small orifices to plug and only periodic inspection is required
  • Initial and operating costs are low compared with other types of equipment. No protective housings are needed and required to operate the pump
  • Systems can be made in practically any workable material

Image - Type 7014 Venturi Scrubber and Separator

How Ejector-Venturi Gas Scrubbing Systems Operate

Image - Type 7014 Venturi Scrubber and Separator

A - Motive (Scrubbing) liquid inlet water or other liquid is supplied to the scrubber under pressure.
B - Spray Nozzle. The motive/scrubbing liquid passes through a specially designed nozzle which breaks the liquid stream into a spray with characteristics most suitable for the maximum entrainment of gas and best possible scrubbing efficiency. The velocity of the liquid spray creates a draft with in the scrubber body.
C - Gas Inlet. Gas, fumes, vapors, or dust are drawn into the body of the scrubber through this inlet connection by the draft producing action of the motive/scrubbing spray.
D - Body. The gases are entrained by the motive/scrubbing spray and begin to mix with it.
E - Venturi (or Diffuser). When the liquid/gas mixture enters this area it is subjected to intense turbulence and the two are thoroughly mixed ensuring that there is maximum contact between them. Compression of gas also occurs creating a differential pressure across the unit.
F - Separator. Non-condensable, washed gases are separated from the liquid in a separator. Separators vary somewhat in design depending upon the application.
G - Clean Gas Outlet. Non-condensable gases which are now clean and free from contamination are discharged to atmosphere or into piping for further use.
H - Liquid Drain. Separated liquid is discharged into a suitable drain or sump, or into a storage tank if the liquid is to be recirculated through the scrubber or to another scrubber in series.