Pelletized iron hydroxide for binding hydrogen sulfide
Hydrogen sulfide in biogas leads to environmental pollution and corrosion problems in pipes and internal combustion engines. Exhaust catalysts used in sequence after CHP units are damaged by hydrogen Sulfide.
Using FerroSorp® S, a pelletized absorption compound based on iron hydroxide, hydrogen sulfide is chemically bound and thus removed from the gas. The material is continuously regenerated by adding air from the surrounding environment. This achieves high loading rates of more than 50% by mass based on the commercial product.
Hydrogen sulfide-containing biogas is passed through a desulfurizer containing the pelletized hydrogen sulfide absorber. A chemical reaction between gaseous hydrogen sulfide and iron hydroxide in the desulfurization pellets produces solid iron sulfide. It is common practice to add atmospheric oxygen which results in a continuous regeneration of the absorption material by forming elemental sulfur, hereby ensuring the highest possible load on the FerroSorp® S.
The pelletized-hydrogen sulfide absorber FerroSorp® S can be particularly beneficial when used in the following desulfurization gas treatment processes:
- Agricultural biogas
- Biogas from fermented waste
- Gas from anaerobic industrial wastewater treatment
- Landfill gas
- Mechanical fuel gas and syntheses gas
- Sewage gas in municipal sewage treatment plants
- Hydrogen sulfide containing gases of different origin
Some siloxane compounds will be removed too.
The equations for the chemical processes taking place during loading and regeneration of the desulfurization pellets can be found in the following scheme:
Advantages at a glance
- Safe procedure tested and used for decades
- High cleaning performance at low cost
- High loading rates due to simultaneous regeneration
- High activity levels of the absorption pellets guarantee a high-level of purification
- Low pressure drop across material due to optimized pellet shape
- Easy and cost-effective disposal of spent material by return guarantee of the supplier