What happens to organic matter after it has gone through the digester?

Almost as much organic matter comes out of a digester as has gone into it. However, digester residue is almost odorless, definitely less polluting and has a reduced organic load (DBO5); it is also higher in fertilising value. Digester residue has a solid component that can be used as compost and a liquid component that can serve as fertilizer or, if subjected to a secondary treatment, can be returned to the natural environment.