A method for the production of cellulose from a waste material 5 comprises: providing a waste material comprising organic material； homogenising the waste material； passing steam 28 through the homogenised waste material to hydrolyse at least a portion of the waste material； and retrieving cellulose from the hydrolysed waste. The hydrolysis is catalysed by the addition of urea or a urea derivative. The waste material is fed into the top 30 of a vertical reaction chamber 21 and retrieved from the base 31. The steam is introduced in to a central portion of the chamber to establish a spiral flow to stir the waste. A heat exchange system is provided for retrieving heat from the cellulose to produce steam. The waste may comprise wood, sewage or packaging materials.
