Biogas Desulfurization: Technology & Sustainability

The turn of biogas into biomethane for injection into natural gas networks, as well as the alternative of "in situ electricity generation", requires the rapid separation of hydrogen sulfide from the biogas process. For this, there are two kinds of removal methods: origin/source or in biogas line (external and inside).

The removal of hydrogen sulfide (H2S) in the biogas stream becomes a necessity not only to keep the pipes, machines, and equipment involved in its transport, use, and application in good condition but also, above all, to preserve the life of all personnel in charge of the operation and maintenance of the biogas production facility, as well as avoiding toxic gas emissions into the atmosphere.

Gas phase: Hydrogen sulfide (H2S)

Liquid phase: Sulfide acid (H2S)

Detection: Strong rotten egg odor

Development

Origin

Hydrogen sulfide (H2S) is present in most rotting or biological degradation processes of organic matter when this process is carried out in the absence of oxygen. Under anaerobic conditions, sulfur-reducing bacteria acquire oxygen from sulfate (SO4), converting it into sulfur (S2-), which will give rise to H2S and hence the presence of H2S in the biogas.

Figure 1. H2S production mechanism

The hydrogen sulfide concentration in the gas…