TYPES OF ANAEROBIC DIGESTION SYSTEMS
There are two general AD system configurations suitable for agri-food systems : completely mixed and plug flow.
Completely mixed
Completely mixed systems, as the name implies, consist of a large tank where fresh material is mixed with partially-digested material. These systems are suitable for manure or other agri-based organic material as substarte with lower dry matter content (4–12 %). Material with higher dry matter content will work in completely mixed systems by using recirculation of liquid effluent. The majority of state-of-the-art biogas digesters utilized in farming operations are completely mixed systems. There are currently more than 5,000 biogas digesters with this type of technology in operation worldwide.
Plug flow
Plug flow systems typically consist of long channels in which the manure and other inputs move along as a plug. These systems are suitable for thicker materials with higher dry matter content.
