A Study on the Flow of Wood Pulp Slurries in a Pipe Line

Abstract

At low velocities the flow of wood pulp slurries in a pipe line is similar to the flow of Bingham fluid, and a thin water film exists between the wall and the main body of the pulp during pulp flow at usual velocities excepting low velocities. The author shows that the coefficient of pipe friction loss f is a function of the single dimensionless number [numerical formula] through all velocities (ρ_p : pulp density, μ_a : average velocity, τ_y : yield stress, α : relative plug radius). Moreover, the singularity of the pressure drop of the flow of sulphite pulp (the pressure drop shows a slight decrease with an increasing velocity and at higher velocities the pressure drop again increases with an increasing velocity) is also explained.