[Trisha]

The concentration of H2S in the biogas will depend on the 1) feedstocks 2) pH 3) temperature. Generally, higher protein feedstocks produce more H2S. Decreasing pH and temperature pushes more H2S in the gas phase (instead of staying in the digestate). There’s a wide range of pH and temperatures that you can operate at to minimize the H2S in the biogas. But pH and temperature won’t fix a problem caused by too much protein (and therefore too much H2S). I’ll link a YouTube video explaining these dynamics.

But if you’re wanting a single H2S or other contaminant concentration that you must not cross, that will depend on the equipment manufacturer’s design for your system and the pipeline standards.

How to Manage H2S in your Digester: https://www.youtube.com/watch?v=GlpwWKjazxg&t=193s