Herbst Umwelttechnik

Herbst Umweltechnik

The HERBST adsorption system H2S-Clean permits complete separation of dissolved H2S from fresh or salt water.

This is done using Iron-III-Hydroxide that separates H2S from water by adsorption and catalysis. Iron-III-Hydroxide is a red-brown iron hydroxide granulate. It is not subject to any water hazard class and entirely non-toxic as well as water-insoluble. Depending on the dissolved oxygen concentration in the water, separation of H2S is performed with the following reactions:

a) Reduction of iron-III-hydroxide


  • 2 Fe (OH)3 + H2S > 2 FE (OH)2 + S + H2O

b) Precipitation of sulfide


  • 2 Fe (OH)3 + H2S > FeS + H2O


Both the precipitated elemental sulfur (S) and the iron sulfide (FeS) are water-insoluble and hence no water hazard in the given concentrations.
Depending on water volume flow, we use either depressurized or pressurized reactors.
Our H2S adsorbers are generally designed to require maintenance and replacement of the used Iron-III-Hydroxide only once every year.
Depending on the pressure loss in the Iron-III-Hydroxide bed, the adsorbers are backflushed. The backflush water removes elemental sulfur and iron sulfide particles from the adsorbers and may be discharged into the sewage water system. If this is not feasible, HERBST UMWELTTECHNIK will provide a backflush water treatment system.


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