Dewatering of fibre suspensions by pressure filtration

Dewatering of fibre suspensions by pressure filtration

Particle-pressure-induced self-filtration in concentrated suspensions.

Gravity-driven flow of concentrated suspensions (solid volume fraction ϕ>0.50) of non-brownian spherical particles through a channel contraction at low Reynolds number is studied experimentally. The abrupt change in the flow area at the contraction forms distinct shear-rate regions having different fluid pressures, which are related to the concept of particle pressure. A model involving particl...

The rheology of fibre suspensions

We review theoretical work on the rheology of fibre suspensions. We seek to clarify one or two confusions in published work and also give a small improvement to Batchelor’s formula for extensional viscosity of suspensions of long fibres between the dilute and semi-dilute régimes.

Sludge Dewatering by Impulse Drying

An innovative and energy efficient sludge dewatering technology has been developed. The technology, impulse drying, involves briefly contacting the sludge under pressure with a heated surface. A unique feature of impulse drying is that the majority of moisture removal occurs as lipid water. A pilotand laboratory-scale demonstration was performed on low ash primary paper mill sludge. The pilot-s...

Liquid pressure measurements in a thermally assisted mechanical dewatering process

The thermally assisted mechanical dewatering process, investigated in this paper, couples in one stage mechanical dewatering at low pressure (Papplied < 1125 kPa) with a moderated heating (T < 80°C). Former studies emphasized that the separation enhancement depends on the product. To identify the mechanisms involved, a 1D filtration/compression cell is instrumented with pore liquid sensors dist...