Abstract:
La présente invention concerne un procédé de traitement de pâte papetière chimique comprenant une étape de traitement de la pâte à l'ozone suivie d'une étape d'extraction alcaline, dans lequel l'extraction alcaline se déroule en présence d'ions magnésium (Mg 2+ ).
Abstract:
A method is provided for controlling deposit-forming contaminants that comprise pitch or other fiber components which can interfere with the processing of the fibers, reduce paper quality, or both in papermaking systems. The method includes contacting fibers with a lipase and at least one peroxide source-free oxidant, and optionally nonionic surfactant, to liberate the organic contaminants from the fibers. Paper products of the method are also provided.
Abstract:
This invention relates to a liquid composition for the control of pitch deposition in pulp and paper making comprising an aqueous solution of (1) a cationic guar polymer, and (2) isobutylene/maleic anhydride copolymer. The invention also relates to a process for inhibiting pitch and stickies deposition in pulp and papermaking systems.
Abstract:
Compositions and methods for inhibiting the deposition of organic contaminants from pulp on the surfaces of pulp and papermaking systems are disclosed. The composition is a combination of a polyvinyl alcohol having 50 to 100 % hydrolysis and a high molecular weight gelatin having a molecular weight of about 100,000 or higher and is added to the pulp or sprayed onto the surfaces of the pulp and papermaking system. In a preferred embodiment, synergism is demonstrated by an 8 to 1 weight ratio of polyvinyl alcohol to high molecular weight gelatin.
Abstract:
Methods to control organic contaminants in fibers are described. One method involves contacting the fibers with a composition containing at least one esterase or lipase or both for a sufficient time and in a sufficient amount to control the organic contaminants present in the fibers. Preferably, the fibers are recycled fibers originating from a variety of sources such as old corrugated containers, old newsprint, mixed office waste, and the like. Resulting paper products formed from the processed fibers are also described as well as methods to make them.
Abstract:
Methods for inhibiting the depositions of organic contaminants from pulp in pulp and papermaking systems are disclosed. Whey proteins or a combination of a protein and a cationic polymer are added to the pulp or applied to deposition prone surfaces of a papermaking system.
Abstract:
Ethyleneamine compound(s), or mixtures thereof, are used in effective amounts to reduce or inhibit the deposition of white pitch on the paper making equipment during the processing to recycle coated paper.
Abstract:
Methods for controlling wax and other contaminants by improving the dispersion of these materials through the addition of contaminant dispersants to the process of recycling paper and paperboard are disclosed. A preferred contaminant dispersant comprises: a) water; b) a plasticizer; c) an anionic dispersant; d) a surfactant wetting agent; and e) either 1) an acid or lecithin and optionally, a base, or 2) a preneutralized component.