A plug screw feeder (1) comprises a plug screw (10) with a thread (12) and a plug screw housing (20) surrounding the plug screw. The plug screw housing comprises an inlet opening (24) in a side of the plug screw and in a vicinity of a first axial end (18) of the plug screw. The plug screw is arranged for feeding lignocellulosic biomass material (99) from the inlet opening to a second axial end (19) of the plug screw when being rotated. The thread, in at least a part of an inlet section (15) of the plug screw, presents a jagged peripheral rim (14A) with an inwards directed leading edge. The inlet section is defined as the section of the plug screw passing the inlet opening during rotation. A feeding arrangement and system for treatment of lignocellulosic biomass material comprising such a plug screw feeder is also disclosed.

An arrangement for feeding and dewatering lignocellulosic material in a hydrolysis process between a first reactor unit, where the material is partly hydrolyzed, to a second reactor unit, wherein the first reactor unit operates at a first pressure and the second reactor unit operates at a second pressure being higher than the first pressure. The arrangement includes a first plug screw feeder arranged to receive the partly hydrolyzed material from the first reactor unit and being arranged to compress, dewater and transport the material, wherein the first screw feeder is arranged to operate at a pressure being higher than the first pressure. A dilution vessel is coupled to receive material from the first plug screw feeder and including a liquid inlet for receiving liquid to wash the material, wherein the dilution vessel is arranged to maintain or increase the pressure (PDM). A second plug screw feeder is arranged to receive the diluted material and to compress, dewater and transport the material to the second reactor unit, wherein the second screw feeder is arranged to operate at a pressure being higher than the pressure of the first plug screw feeder. A system including such an arrangement and a first reactor unit and a second reactor unit is also presented.

There is provided a method for separation of fibers in for instance recycled textile, starting with a mixture comprising cellulose fibers and non-cellulose fibers and then reducing the cellulose chain length of the cellulose fibers so that the limiting viscosity number determined according to ISO 5351 is in the interval 200-900 ml/g, mechanically breaking agglomerates of fibers into smaller pieces, adjusting the concentration of fibers to 0.1-4 wt %, and subjecting the mixture to flotation to remove the non-cellulose fibers. Non-cellulosic fibers such as synthetic fibers can be removed very specifically without or essentially without removing cellulose fibers in the mixture. This gives a very high degree of removal and simultaneously the yield is kept high because no or only few cellulose fibers are removed.

An arrangement for feeding and dewatering lignocellulosic material in a hydrolysis process between a first reactor unit, where the material is partly hydrolyzed, to a second reactor unit, wherein the first reactor unit operates at a first pressure and the second reactor unit operates at a second pressure being higher than the first pressure. The arrangement includes a first plug screw feeder arranged to receive the partly hydrolyzed material from the first reactor unit and being arranged to compress, dewater and transport the material, wherein the first screw feeder is arranged to operate at a pressure being higher than the first pressure. A dilution vessel is coupled to receive material from the first plug screw feeder and including a liquid inlet for receiving liquid to wash the material, wherein the dilution vessel is arranged to maintain or increase the pressure (PDM). A second plug screw feeder is arranged to receive the diluted material and to compress, dewater and transport the material to the second reactor unit, wherein the second screw feeder is arranged to operate at a pressure being higher than the pressure of the first plug screw feeder. A system including such an arrangement and a first reactor unit and a second reactor unit is also presented.

A feeding arrangement for feeding comminuted material to a treatment stage using a plug screw feeder. The invention relates to a design of the inlet to the plug screw feeder wherein, at least 2 chutes (20a,20b) are arranged to feed material to the feed screw (10), and that the cross section of each chute is arranged such that more than 50% of the outlet cross section of a first chute (20a) is located on one side of the feed screw axis (CC) and more than 50% of the outlet cross section of a second chute (20b) is located on the other side of the feed screw axis. In an upgrade version for existing plug screw feeders with large rectangular inlets is an insert body (11a) used filling the rectangular inlet, besides the chutes (20a, 20b) passing through the insert body (11a).

A feeding arrangement for feeding comminuted material to a treatment stage using a plug screw feeder. The invention relates to a design of the inlet to the plug screw feeder wherein, at least 2 chutes (20a,20b) are arranged to feed material to the feed screw (10), and that the cross section of each chute is arranged such that more than 50% of the outlet cross section of a first chute (20a) is located on one side of the feed screw axis (CC) and more than 50% of the outlet cross section of a second chute (20b) is located on the other side of the feed screw axis. In an upgrade version for existing plug screw feeders with large rectangular inlets is an insert body (11a) used filling the rectangular inlet, besides the chutes (20a, 20b) passing through the insert body (11a).