The University of British Columbia

Fpinnovations

Pulp and Paper Research Institute of Canada

James Allen Olson

James M Lockhart

Dominic Mark Martinez

John David Hoffmann

Timothy D Finnigan

Davood Farajisarir

Andrew G Robertson

Ian Alistair Frigaard

Ario Madani

Jordan Ko

Particles are separated from a source viscoplastic fluid by flowing streams of the viscoplastic fluid and a destination fluid in parallel streamed relationship inside a rotating cylindrical annulus by using baffles to introduce each fluid independently at an inlet lower end of the annulus and for separating the upper streams consisting of an un-yielded source and destination flow proximate the radially innermost side of the annulus, a bulk axial flow in a more central region and a yielded layer destination flow adjacent the radial outermost side of the annulus which contains the particles that have separated. Inlet and outlet baffles are provided at each end of the vertically oriented device to maintain the flows discrete on entry and to maintain the separated flows discrete on exit so as to facilitate removal of the component flows from the fractionator.

Method and apparatus for continuously fractionating particles contained within a viscoplastic fluid

A method and system for determining trace oversize contaminant particles in a paper-making pulp employs a screen assembly having a screen housing with a screen mounted therein, and ports for introduction of aqueous pulp and rinsing and flushing fluids, and for withdrawal of screened aqueous pulp, the screen housing has no port designated for the sole purpose of removing accumulated contaminant particles from the screen housing; instead the port employed for introduction of aqueous pulp and which may also be employed for introduction of rinsing fluid to the housing, is employed as the flushing port for removal of contaminant particles.

Determination of contaminant particles in an aqueous pulp

A the operation of pulp screening apparatus may be improved by employing a multi element foil having a leading foil section and a trailing foil section spaced from and trailing leading section so that adjacent surfaces of the sections one formed by a portion of a pressure side of the leading section and the other by the leading end of the trailing foil section define opposed walls of a passage for fluid directing fluid flow from the pressure side of the leading foil section to a cambered low pressure side of the trailing section. The angle of attack (&#x3b1;) of the complete multi element foil is set to be significantly less than the angle of attack (&#x3b8;) of the trailing foil section to increase the negative pressure pulse generated by the trailing section and thereby improve operation of the screening device.

Multi-element airfoil for pulp screens

A method and apparatus for positioning, aligning and orienting fibers in flowing fluids, to permit fibers such as wood pulp fibers to be accurately imaged and rapidly measured with little operator involvement, utilizing a plugging resistant and fouling resistant sheath flow cell, is described. An embodiment is disclosed which simultaneously determines the distributions of shape (curl) and length of samples of wood pulp fibers. Fibers are transported in a dilute water suspension through a sheath flow cell that orients fibers normal to an imaging system that includes a two-dimensional CCD video camera. Images of fibers are analyzed rapidly by a processor, which calculates the shape and length of individual fibers. The data are displayed on a cathode ray tube screen while a pulp sample is being analyzed, and are stored in processor memory for further analysis.

Imaging apparatus and method of fiber analysis

Growing community of inventors

Delta, Canada

James Allen Olson