Kvaerner Pulping Ab

Re:newcell Ab

Cleanflow Ab

Valmet Ab

Circulose Ab

Christofer Lindgren

Mikael H Lindstrom

Vidar Martin Snekkenes

Krister Olsson

Gunnar Henriksson

Mikael Lindström

Johan Engstrom

Soren Gustavsson

Johan Engstr&ouml;m

Lennart Kållén

Eva Hogebrandt

Stefan Antonsson

S&ouml;ren Gustavsson

Mikael Lindstr&ouml;m

Lennart Borjeson

Lennart Källén

Mikael LINDSTRÖM

Lennart Börjeson

A method for recycling textiles comprising cellulose with the following steps of: optionally disintegrating the textile, swelling the cellulose, under reducing conditions, wherein at least one reducing agent is present at least during a part of the swelling, and then performing at least one of the following two bleaching steps in any order: i) bleaching the material with oxygen at alkaline conditions with a pH in the range 9-13.5, and ii) bleaching the material with ozone at acid conditions below pH 6. An advantage is that the yield is improved at the same time as excellent decolourization is achieved. If the recycled material is used in viscose manufacture, the risk of clogging nozzles and so on is reduced.

Recycling of cellulosic textiles

A method for recycling textiles comprising cellulose with the following steps of: optionally disintegrating the textile, Swelling the cellulose, under reducing conditions, wherein at least one reducing agent is present at least during a part of the swelling, and then performing at least one of the following two bleaching steps in any order: i) bleaching the material with oxygen at alkaline conditions with a pH in the range 9-13.5, and ii) bleaching the material with ozone at acid conditions below pH 6. An advantage is that the yield is improved at the same time as excellent decolourization is achieved. If the recycled material is used in viscose manufacture, the risk of clogging nozzles and so on is reduced.

There is provided a cellulose based fiber made of a i) cellulose dissolving pulp, and ii) a recycled cellulose textile, which is treated to swell the cellulose with a reducing additive and a) bleached with oxygen at alkaline conditions with a pH in the range 9-13.5 and/or b) bleached with ozone at acid conditions below pH 6, wherein the cellulose based fiber is manufactured with one selected from a Viscose process and a Lyocell process. Advantages include that the tensile strength of the fiber is improved and it is possible to manufacture improved cellulose fibers which comprise a fraction of recycled material.

Cellulose fibers

Green liquor clarification comprising filtering of a flowing suspension containing solids, wherein the suspension is brought into contact with a first filter unit (), said 5 filter unit () comprising one or several filter elements () comprising one or several filter bodies () having filter channels () within the filter bodies () with a filtering layer (), a part of the suspension is forced to pass through the filtering layer () from a first/inner surface (A) to a second/outer surface (B) of the filtering layer () forming a filtrate while the solids substantially remains in a residual part of the suspension forming a slurry and where the filtering layer () is made of a membrane material with pores, said pores having a pore size of 0.1-10 micrometer, more preferred 0.1-5 micrometer and most preferred 0.2-1.0 micrometer.

Method and arrangement for clarifying green liquor

This invention relates to a new and improved way of continuously cooking fiber material, wherein temperatures and alkaline levels are controlled to be maintained within specific levels in different zones of the digesting process in order to optimize chemical consumption and heat-economy, and, at the same time, achieving very good pulp properties.

Method for the continuous cooking of pulp in a digester system having a top separator

Method and device for the continuous cooking of pulp

This invention relates to a new and improved way of continuously cooking fiber material, wherein temperatures and alkaline levels are controlled to be maintained within specific levels in different zones of the digesting process in order to optimize chemical consumption and heat-economy and at the same time achieve very good pulp properties.

Method for the continuous cooking of pulp

A method and device for cooking pulp by increasing the effective alkali concentration in the residual phase of the cooking process to substantially improve the residual delignification rate and thus improving the pulp properties such as the pulp strength and pulp yield at a given lignin content.

Method of producing pulp with high alkali cooking in the last cooking

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Stockholm, Sweden

Christofer Lindgren