Digestate
Overview
Anaerobic digestion
Anaerobic digestion is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen. It is used for industrial or domestic purposes to manage waste and/or to release energy....
produces two main products: digestate and biogas
Biogas
Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal dung, and kitchen waste can be converted into a gaseous fuel called biogas...
. Digestate is produced both by acidogenesis
Acidogenesis
Acidogenesis represents the second stage in the four stages of anaerobic digestion:* Hydrolysis: A chemical reaction where particulates are solubilized and large polymers converted into simpler monomers;...
and methanogenesis
Methanogenesis
Methanogenesis or biomethanation is the formation of methane by microbes known as methanogens. Organisms capable of producing methane have been identified only from the domain Archaea, a group phylogenetically distinct from both eukaryotes and bacteria, although many live in close association with...
and each has different characteristics.
Acidogenic digestate is fibrous and consists of structural plant matter including lignin
Lignin
Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. The term was introduced in 1819 by de Candolle and is derived from the Latin word lignum, meaning wood...
and cellulose
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....
. Acidogenic digestate has high moisture retention properties.