Manufacturing

Wet Scrubber Manufacturing and Fabrication

A wet scrubber is an air cleaning device where a dust-laden air stream is brought into contact with a scrubbing liquid (generally water), and the fine particulates are captured by the liquid droplets and, hence, removed from the air. Dirty water exits the device, but the cleaned air will still retain a fine mist.

Two-Stage Design: It is necessary for a wet scrubber to have a second stage, called a mist eliminator, to remove these fine droplets. Wet scrubbers can also be used to absorb noxious constituents from the gas, but the design criteria for gas absorption can be quite different from those for particulate removal.

Low-Energy Scrubbers

BCE Low-energy scrubbers are used to collect particles greater than 5 microns. An example of this type is a spray tower.

Spray Tower Design

  • Cylindrical vessel fitted with rows of water pipes to spray down on rising inlet air
  • Droplet size: 500-1000 microns (relatively large compared to high-energy scrubbers)
  • Air velocity: 1-4 ft/sec (low velocity to prevent droplet entrainment)
  • Larger droplets reduce efficiency
  • Low air velocity requires a larger vessel size for the same air volume

Other Low-Energy Types

  • Orifice scrubbers
  • Dynamic wet precipitators

High-Energy Wet Scrubbers

BCE High-energy wet scrubbers are used to collect submicron particles. Two common designs of high-energy wet scrubbers are the venturi scrubber and the packed tower, both designed to provide effective contact of water droplets with the dust-laden inlet air.

Venturi Scrubber

The BCE Venturi Scrubber, as the name implies, contains a converging section, throat, and diverging section.

  • Dust-laden air enters at the top of the converging section
  • Scrubbing liquid injected either at the entrance of the converging section or at the throat
  • Area reduction causes air to reach high velocity
  • High velocity strips water from the scrubber wall, forming countless small droplets
  • Droplets capture particles in the venturi throat
  • Mist eliminator is usually a cyclonic separator directly coupled to the scrubber

Packed Tower

The packed tower consists of a single cylindrical vessel where the inlet air and water contact each other countercurrently in a packed bed.

  • Inlet air and water contact countercurrently in a packed bed
  • Mist eliminator located at the top of the vessel
  • Removes fine droplets before cleaned air exits through the top outlet
  • Packed beds provide a large area of contact
  • Promotes intimate contact between gas and liquid phases

Advantages of BCE Wet Scrubbers

Performance Benefits

  • Can handle high-temperature gas streams
  • Capable of high collection efficiency
  • Reduces temperature of exhaust stream

Operational Advantages

  • Low initial cost
  • Small space to install
  • Separates explosive solids from gas streams

Application Expertise: BCE engineers will help you determine whether a low-energy or high-energy wet scrubber is best suited for your specific application, considering factors such as particle size, temperature, space constraints, and efficiency requirements. Contact us to discuss your air pollution control needs.