A waste treatment process including the steps of: (i) passing waste material which may comprise animal or human faeces comprising an insoluble component such as lignocellulose through a bioreactor system including a plurality of bioreactors in series and maintaining said insoluble component as a suspension in said waste material; and (ii) separating suitably by filtration the insoluble component from the waste material. A waste treatment plant including: (i) a bioreactor system including a plurality of bioreactors in series for treatment of waste material; (ii) means such as filtration for separating an insoluble component from said waste material after passage through the bioreactor system.