Alkaline scrubber in the meat processing and dairy industry

Residual products in the meat processing industry unfortunately often create unpleasant odours, take hydrogen sulphide (H₂S) as an example. This is a strong smelling toxic gas known particularly as the smell of rotten eggs. Because of its toxicity, breathing low concentrations of hydrogen sulphide for a longer period of time is potentially dangerous. Hydrogen sulphide can, depending on other sulphur bound pollutants (mercaptans for example), be well removed from an air stream in an alkaline scrubber, sometimes an odour scrubber is a better solution.

An alkaline air scrubber can remove acidic components from an air stream. By adding a base (lye), the pH of the washing water is raised and the acid forming components are neutralized by the lye, whereby salts are formed. The dosing of the base is done by means of a pH control, in most cases the pH value of the washing water varies between 7 and 12.

Depending on the salt formed, more or less washing water is discharged, this is measured on the basis of density and/or conductivity. The drainage can contain up to 15 % of salts and is discharged or evaporated for reuse.

Usually caustic soda (NaOH) is added as a base to the washing water. Often an alkaline scrubber is designed in combination with an odour scrubber. Besides caustic soda, a chlorine solution is dosed to oxidize all odour components. For more information please refer to the odour scrubber.

The advantages of an Air Solutions alkaline scrubber are:

• Completely made of plastic to prevent corrosion
• Relatively compact
• Horizontal and vertical airflow possible
• Very high removal efficiency
• Can be built modular, multi-stage systems
• The formed salts can be reprocessed and reused

Air Solutions has experience with basic washers in the following industries:

• MDF wood pressing (formaldehyde)
• Waste treatment plant (hydrogen sulphide H2S)
• Chemical industry (chlorine neutralisation)
• Pharmaceutical industry (phenols and hydrogen fluoride)

Quality marks:

• ISO 9002
• CE
• KIWA
• VLAREM
• DVS welding certification