society > occupation and work > equipment > paper-making equipment > [noun] > for breaking down lumps in pulp (2)
An apparatus for refining; (Papermaking) a machine in which knots and lumps in the pulp fibres are broken down before the pulp is made into paper.
A large vessel with a set of motor-driven rotating vanes at the bottom, designed to break up the fibres of wood pulp or other paper stock in water.