Fpinnovations

Pulp and Paper Research Institute of Canada

Lahoucine Ettaleb

Keith Miles

Makhlouf Laleg

Alain André Roche

Gilles Marcel Dorris

Xujun Hua

Reza Amiri

Alain Roche

Michael Stacey

Alain Andre Roche

The present invention is directed to a method of transforming a pulp fibrous into a pre-dispersed semi-dry or dry fibrous material and to the material produced. The method opens, de-entangles and fibrillates the fibrous material of the input pulp. The method mixes the input fibrous with chemicals while evaporating moisture in an updated mechanical disc refiner process. The refiner operates to set three process variables: 1) applied refining specific energy; 2) refiner gap opening and 3) refiner output consistency. Depending on the feed pulp type and consistency, the refiner's output is a pre-dispersed semi-dry fibrous material of 30 to 99% solids with 70 to 100% of separated fibers that depending on chemical treatment are loosely entangled fibrous that disperse in water using common techniques. The pre-dispersed semi-dry output may be further processed inline or by batch process air agitation at velocities sufficient to further separate fibers and loosen fibrous entanglements.

Method of transforming high consistency pulp fibers into pre-dispersed semi-dry and dry fibrous materials

A method to produce on a commercial scale, high aspect ratio cellulose nanofilaments (CNF) from natural lignocellulosic fibers comprises a multi-pass high consistency refining (HCR) of chemical or mechanical fibers using combinations of refining intensity and specific energy. The CNF produced represents a mixture of fine filaments with widths in the submicron and lengths from tens of micrometers to few millimeters. The product has a population of free filaments and filaments bound to the fiber core from which they were produced. The proportion of free and bound filaments is governed in large part by total specific energy applied to the pulp in the refiner, and differs from other cellulose fibrillar materials by their higher aspect ratio and the preserved degree of polymerization (DP) of cellulose, and are excellent additives for the reinforcement of paper, tissue, paperboard and the like. They display exceptional strengthening power for never-dried paper webs.

High aspect ratio cellulose nanofilaments and method for their production

A method has been developed that estimates from the on line measurements of readily available process variables the proportion of the mass of fiber in the refining zone of a chip refiner relative to the mass with a full refining zone. This estimate of the filling factor is used to determine the margin available to load the refiner and the control action needed to avoid abnormal operation.

Method of controlling wood pulp production in a chip refiner

A method is proposed for improving pulp quality at high production rates on conical disc refiners. It permits a reduction in refining intensity by enabling fibre residence time to increase by increasing consistency, while avoiding the problem of plate plugging normally associated with high discharge consistency. In practice, inlet consistency is increased by the in-feed dilution, flat zone dilution or both, but without allowing the discharge consistency to rise. Instead, the discharge consistency is controlled at a fixed optimum value by the addition of dilution water within the conical zone. The result is that residence time is increased, and refining intensity decreased, by raising the consistency in the inner region of the refining zone, while avoiding the plate plugging caused by excessive consistency in the outer region of the refining zone.

Method of refining wood chips or pulp in a high consistency conical disc refiner

A method and apparatus to perform an automatic diagnosis for the poor performance of a control loop, and to determine whether or not the malfunctioning is caused principally by a poor adjustment of the controller tuning parameters. The method makes use of the fact that a poorly tuned control loop amplifies disturbances in a narrow frequency range around the so-called resonant frequency. The method comprises measuring an error in a control loop over time to determine a power spectral density of the error, determining a best fit analytical function describing the power spectral density and measuring a diagnostic value from a difference between the best fit analytical function and the power spectral density of the error.

Growing community of inventors

Pointe-Claire, Canada

Lahoucine Ettaleb