What is FeSfix?

FeSfix is the latest generation product to deal with desulphurisation in anaerobic fermentation industry, developed in cooperation with German scientific institutions. It comes in powder form, working on the basis of Fe2O3, which binds hydrogen sulphide (H2S) contained in ferments during the process of anaerobic fermentation in biogas plants.

FeO + H2S ➙ FeS + H2O
2H2S + O2 ➙ 2S + 2H2O (adding air)
2Fe3+ + 3S2- ↔ 2FeS + S

It is well known that H2S hinders the process of methanogenesis thereby also displacing trace elements necessary for methanogenic bacteria. This results in a significant drop in biogas production. Therefore, the target should be to put a desulphurisation process in place that allows the anaerobic bacteria to focus on methane production. Other desulphurisation methods based on the principle of adsorption by activated carbon or the addition of air into the fermenter, do not provide such an economic solution as FeSfix.


What are the benefits of FeSfix?

  • Formation of sulphides in ferments replaces increased amounts of H2S in the gas phase.
  • The process of methanogenesis is no longer hindered by a high concentration of H2S.
  • Corrosive effects on concrete and metal parts of equipment are limited. Improved availability of trace elements to bacteria and as a consequence obtention of a higher biogas yield.
  • There is no ferment salinity as in the case of using toxic iron chloride (FeCl3).
  • FeSfix has a low content of highly toxic CrVI when compared with other products such as ferrous hydroxide.
  • The actual sulphur remains in the digestate and is then applied to the soil as a valuable sulphur fertiliser.
  • The high content of trace elements (Co, Ni, Cu, Mn, Zn, B, V, Al) in FeSfix optimises the process of anaerobic fermentation.
  • The presence of Nickel in FeSfix enhances the formation of the F420 and F430 coenzymes, which are important carriers of hydrogen in the process of methanogenesis.

  • Thanks to its increased sulphur and iron content the digestate is a valuable substrate, particularly for growing mushrooms.
  • Longer lifetime of oil in the co-generator and a reduction in dosing of trace elements lead to significant financial savings.
  • FeSfix contains 50% Fe allowing for a lower daily dosage, compared to other products containing Fe(OH)3, Fe(OH)2, or FeCl3 where iron concentration ranges between 9 and 30%.

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