Horizontal digesters can also run in parallel, in order to achieve larger throughput quantities.
Because of their shape, the plug-flow stream is automatically used. The feedstock flows
slowly from the entry side to the discharge side, forming a plug-flow, streaming through the
digester. The risk of discharging un-decomposed substrate is minimised through a minimum
guaranteed retention time (MGRT) of the substrate inside the digester. Horizontal continuous
flow digesters are usually used for feedstock like chicken manure, grass, maize silage or
manure with a high straw content