NEUTRALISATION

Reaction of acid and base under formation of salts and water.
Many types of commercial and industrial wastewater must be neutralised before discharging it into public sewer system or receiving water.

Acidic water is thus neutralised with base (e.g. lime water, caustic soda, soda solution). In recent years, the use of flue gas has been developed as special economical method for neutralisation of alkaline wastewater.

Neutralisation is however not only adjusting to pH 7 but also adjusting to special pH values, amongst others, for precipitation of heavy metals hydroxides. A common disadvantage of this method is the increase of salt load in the wastewater.