H2S removal

Why removal of H2S is mandatory

Biogas is typically used in gas engines for combined heat and power production (CHP) or in boilers for steam or power production. During combustion the H2S will convert to H2SO4 (sulfuric acid). This acid is extremely corrosive and will destroy the engine or boiler in a very short time. Therefore, it is absolutely necessary to remove the H2S before combustion.

The corrosion will literally reduce the lifetime of the downstream equipment by years! This is why gas engine manufacturers require that H2S in the clean gas must not exceed 50-250 ppm. Otherwise, the operating costs for change of engine oil, spark plugs and other maintenance will increase significantly. Furthermore, there will be high costs for repairs and income lost during overhauls and break downs.

Air quality standards are another driver for H2S removal. Combustion of un-cleaned biogas will result in sulfur dioxide (SO2) emissions which causes serious odor problems as well as acid rain. Also health and safety standards require H2S removal as H2S is toxic even in small concentrations.

In upgrading projects the biogas is converted to biomethane or Renewable Natural Gas (RNG) by separating the CO2 from CH4. When the biogas is upgraded with amine or water scrubbing the H2S will follow the CO2 stream. Before releasing the CO2 into the atmosphere the H2S has to be removed.

We look forward to meeting you

Please contact us if you need an efficient solution for desulfurization of biogas. We can help you for any biogas flow and H2S load and no matter if your project is greenfield or refurbishment of an existing plant. We will be happy to share our experience with you. Together, we will find the optimal solution for your biogas plant.


Thorkil Dahlgreen
Founder of Biogasclean

Peter Thygesen
CTO and COO Biogasclean

Jesper Hørlyk-Jensen
Sales Director

Ho Vooi Toc
Sales Manager South
East Asia