Abstract:
Procédé de fabrication d'une feuille de papier et/ou de carton, selon lequel, dans une installation comprenant une pompe de dilution et une caisse de tête: -on prépare une suspension fibreuse cellulosique, -on introduit dans la pâte épaisse les eaux blanches; -on homogénéise le mélange dans la pompe de dilution; -on transfert la pâte diluée jusqu'à la caisse de tête; -on forme puis on sèche la feuille, caractérisé en ce que, avant homogénéisation du mélange dans la pompe de dilution, on introduit un copolymère cationique obtenu par réaction de dégradation dite d'Hofmann dans les eaux blanches et/ou la pâte épaisse et/ou le mélange formé par les eaux blanches et la pâte épaisse.
Abstract:
A process for the production of paper, board, and cardboard is disclosed. The process comprises adding to the wet end of a paper machine (a) microfibrillated cellulose and (b) a coadditive. The coadditive can be one or more of (1) a cationic aqueous dispersion polymer, (2) colloidal silica, (3) bentonite clay and (4) vinylamine -containing polymers and combinations thereof. The invention further relates to a paper product produced by such process.
Abstract:
Unbleached sulphate fibres are chemically separated from other fibres by the use of high molecular polyalkylene oxides, preferably polyethylene oxide. The polyalkylene oxides are added to aqueous suspensions of fibre mixtures and hereby flocculates unbleached sulphate fibres in a selective manner and the flocks can be separated by known methods such as sedimentation, flotation, filtration etc. Use of polyalkylene oxides for selective flocculation of unbleached sulphate fibres gives the possibility of upgrading for example recovered fibres, broke and secondary fibre raw materials.
Abstract:
Die Erfindung betrifft ein Verfahren sowie dazugehörige Vorrichtungen zur Unterstützung der Leimung und/oder zum Fixieren von Störstoffen und/oder zur Erhöhung der Retention bei einer Faserstoffsuspension (1) mittels Metall-Ionen. Um dies unabhängig vom pH-Wert der Faserstoffsuspension (1) zu ermöglichen, werden die Metall-Ionen zumindest vorwiegend elektrolytisch erzeugt.
Abstract:
The present invention relates to a device and a method for increasing the yield, as well as for enabling an increase in productivity and an increased amount of production, and at the same time to improve purification of process water and waste water, respectivel by decreasing the waste water flow and the amount of pollutants in the waste water.
Abstract:
An arrangement for the separation by flocculation of flocculable substances contained in a suspension used particularly for purifying effluents from deinking installations where are processed used or waste paper, comprises a container (4) supplied by a conduit (2) with a suspension coming from a tank (1) and mixed with flocculating agents and with air. The container (4) contains a vertical shaft rotor (34) from which two arms (35, 36) extend outwardly at different heights. The suspension to be purified is introduced above the shaft (34) and the upper arm (36), and purified water is drawn above the lower arm (35) which forms with the upper arm an acute angle so that it precedes the latter during the rotation thereof. The supernatent substances are optionally removed from the surface by a transportation device (40) in the form of supernatent muds (8) and evacuated through a mud conduit (42).
Abstract:
The present invention provides a method and system for measuring disintegration of a fibrous product. The method comprises disintegration of a sample of the fibrous product in an aqueous solution, optionally promoted by mechanical energy, passing the aqueous solution through a screen to obtain a permeate and retained fraction on the screen, and analyzing at least one parameter from the permeate for example by a gravimetric analysis, an optical analysis, an electrochemical analysis, a volumetric analysis, or combination thereof. Advantages include adjustabilxity, speed, and high correlation with actual flushability or repulpability of the fibrous product, and utility in a process for manufacturing a fibrous sheet exhibiting con- trolled disintegration, such as a flushable or repulpable fibrous sheet.
Abstract:
The invention provides an additive and method for improving dewatering efficiency in a paper making process. The dewatering additive is prepared from the same wood that is used as raw material for preparing the paper, which may be insulation paper or pressboard. The dewatering additive may be prepared from the same pulp that is used for preparing a stock for paper / pressboard forming. The dewatering additive is added to the pulp for preparing the stock that is supplied through various sections of the paper machine for making paper.