Patent classifications
D21C9/08
Compositions for bleaching pulps and their use
Compositions suitable for use in the bleaching of pulps may include one or more particulate alkaline earth metal oxides or alkaline earth metal hydroxides or mixtures thereof, and one or more pitch control additives. The compositions may be suitable for use in a pulp preparation or a papermaking process. A method for the bleaching of pulps may include providing the composition.
Compositions for bleaching pulps and their use
Compositions suitable for use in the bleaching of pulps may include one or more particulate alkaline earth metal oxides or alkaline earth metal hydroxides or mixtures thereof, and one or more pitch control additives. The compositions may be suitable for use in a pulp preparation or a papermaking process. A method for the bleaching of pulps may include providing the composition.
Method for producing cellulose filaments with less refining energy
A novel method is disclosed to make cellulose filaments (CF) from wood or other plant fibers with lower energy consumption. The method consists of multi-stage, high consistency refining, followed by low consistency refining or by low consistency, non-refining mechanical treatment, of wood or other plant fibers. The total specific refining energy for the multi-stage, high consistency refining is preferably 2,000-18,000 kWh/t, and more preferably 2,000-12,000 kWh/t. The CF produced can be used as a superior reinforcement additive in the production of paper, tissue or paperboard and in the production of plastic composites. It can also be used as a viscosity or rheology modifier in food products, coatings or drilling muds. The CF produced can also be used to make strong films for application in packaging and in composites.
Method for producing cellulose filaments with less refining energy
A novel method is disclosed to make cellulose filaments (CF) from wood or other plant fibers with lower energy consumption. The method consists of multi-stage, high consistency refining, followed by low consistency refining or by low consistency, non-refining mechanical treatment, of wood or other plant fibers. The total specific refining energy for the multi-stage, high consistency refining is preferably 2,000-18,000 kWh/t, and more preferably 2,000-12,000 kWh/t. The CF produced can be used as a superior reinforcement additive in the production of paper, tissue or paperboard and in the production of plastic composites. It can also be used as a viscosity or rheology modifier in food products, coatings or drilling muds. The CF produced can also be used to make strong films for application in packaging and in composites.
Process for preparing cellulose solution and equipment therefor
The present invention provides a process for preparing a cellulose solution. NMMO with a relatively low concentration and non-activated pulp are continuously mixed online, the mixed premix is dewatered in evaporation dewatering equipment until an NMMO concentration suitable for swelling is achieved, then, sufficient swelling is carried out under this condition, and the uniformly-mixed and sufficiently swelled pre-swelling solution is subjected to depressurized evaporation dewatering and dissolving by thin-film-evaporation equipment thereby obtaining a high-concentration, uniformly-dissolved and excellently-uniformity cellulose solution. The present invention further provides continuous preparation equipment for the process for preparing a cellulose solution. According to the present invention, the conflict between uniform mixing and sufficient swelling during the preparation of a high-concentration cellulose solution is solved, and problems in storage and transportation safety caused by using high concentration NMMO in the conventional technologies are prevented.
METHOD FOR PRODUCING RECYCLED FIBERS, AND RECYCLED FIBERS
In this method of producing recycled fibers by removing superabsorbent polymers from fibers containing superabsorbent polymers, recycled fibers are efficiently produced while the superabsorbent polymers are suitably removed from the fibers. This method produces recycled fibers from a mixture of fibers and superabsorbent polymers. This method involves a continuous treatment step (S36) in which, in a treatment tank (31) having a treatment solution that can dissolve superabsorbent polymers, superabsorbent polymers are dissolved while a mixed solution (51) that contains water and fibers containing superabsorbent polymers is continuously supplied at a first flow rate, and the treatment solution (52) containing the removed fibers is continuously discharged to outside of the treatment tank at a second flow rate.
Process for producing a pulp
The invention relates to a process for producing a dissolving pulp from a cellulosic starting material using the kraft process, comprising the step of cooking the starting material with a cooking liquor. The process according to the invention characterized in that the starting material is exposed to a steam treatment prior to cooking and that the pulp obtained by cooking is subjected to cold caustic extraction (CCE) in the course of further processing.
Process for producing a pulp
The invention relates to a process for producing a dissolving pulp from a cellulosic starting material using the kraft process, comprising the step of cooking the starting material with a cooking liquor. The process according to the invention characterized in that the starting material is exposed to a steam treatment prior to cooking and that the pulp obtained by cooking is subjected to cold caustic extraction (CCE) in the course of further processing.
Enzymatic treatment of virgin fiber and recycled paper to reduce residual mineral oil levels for paper production
Compositions comprising enzyme compositions are provided. Also provided are methods of treating virgin fiber and recycled wastepaper containing mineral oils using the compositions comprising enzyme compositions. The mineral oils generally originate from wastepapers with mineral oil based inks and certain other hydrocarbon-based chemistries used during the manufacturing, paperboard converting, and packaging process. The enzymes break down or modify mineral oils present in the fiber and paper, mobilize and liberate them from the fibers, and increase removal of mineral oils during paper recycling, pulping and papermaking processes. The method results in the break down or modification of mineral oil components in wastepaper, recycled pulp, and paper products by the enzyme compositions so that the mineral oils can be more efficiently detached and removed. The resulting pulp and paper has much reduced mineral oil concentration or less problematic forms of mineral oils and is beneficial for making food packaging paper products.
Enzymatic treatment of virgin fiber and recycled paper to reduce residual mineral oil levels for paper production
Compositions comprising enzyme compositions are provided. Also provided are methods of treating virgin fiber and recycled wastepaper containing mineral oils using the compositions comprising enzyme compositions. The mineral oils generally originate from wastepapers with mineral oil based inks and certain other hydrocarbon-based chemistries used during the manufacturing, paperboard converting, and packaging process. The enzymes break down or modify mineral oils present in the fiber and paper, mobilize and liberate them from the fibers, and increase removal of mineral oils during paper recycling, pulping and papermaking processes. The method results in the break down or modification of mineral oil components in wastepaper, recycled pulp, and paper products by the enzyme compositions so that the mineral oils can be more efficiently detached and removed. The resulting pulp and paper has much reduced mineral oil concentration or less problematic forms of mineral oils and is beneficial for making food packaging paper products.