Anaerobic digestion (AD) is like the dream come true — you get the green energy and the soil amendment. I’ve been asked to talk about whether the material coming out of a digester — referred to as digestate — is as good for soils as compost or municipal biosolids (itself a digestate). AD is a process that is very common in municipal wastewater treatment. It started as a way for the solids to meet regulatory requirements for pathogen destruction and volatile solids reduction. What that means in English is that the AD process — which involves specialized microbes feasting on the carbon coming into the digester — will eat pathogenic bugs in the process. They will also eat whatever else they are able to. By doing this, the material coming out of the digestion process will have a significantly reduced ability to rot and stink. More >>