A screen assembly for a digester, impregnation vessel or other treatment vessel for separation of cooking liquor or treatment liquor from lignocellulosic material, typically in a form of chips, in the production of chemical cellulose pulp, which screen assembly includes a plurality of screen panels (17) of woven wire mesh cloth and attachment device configured to attach the screen panels to a support frame of the digester or vessel.

A screen assembly for a digester, impregnation vessel or other treatment vessel for separation of cooking liquor or treatment liquor from lignocellulosic material, typically in a form of chips, in the production of chemical cellulose pulp, which screen assembly includes a plurality of screen panels (17) of woven wire mesh cloth and attachment device configured to attach the screen panels to a support frame of the digester or vessel.

The invention relates to an improved profile bar screen for draining treatment liquor from a suspension of comminuted cellulose material and treatment liquor in an essentially cylindrical digester vessel. According to the invention is a profile bar screen designed with horizontal support arches 11 with integrated support shoulders 12 only at the outer ends of the support arch which support shoulders rest against the inside of the vessel wall 1. The invention combines the techniques from self-supporting screens with support members of weaker screen designs, avoiding need to make any additional welds in the classified pressure vessel wall of the digester. Installation of new screens in compartments previously equipped with blind plates in checkered screen rows may be done quickly and at less costs during shorter down time of digester.

The invention relates to an improved profile bar screen for draining treatment liquor from a suspension of comminuted cellulose material and treatment liquor in an essentially cylindrical digester vessel. According to the invention is a profile bar screen designed with horizontal support arches 11 with integrated support shoulders 12 only at the outer ends of the support arch which support shoulders rest against the inside of the vessel wall 1. The invention combines the techniques from self-supporting screens with support members of weaker screen designs, avoiding need to make any additional welds in the classified pressure vessel wall of the digester. Installation of new screens in compartments previously equipped with blind plates in checkered screen rows may be done quickly and at less costs during shorter down time of digester.

The bin arrangement is for collecting and discharging smaller ligno-cellulosic material. The bin has a transition part from a circular section of the bin and downwardly to a rectangular section with a long and short side of the rectangular section. The transition part could be built with few wall segments, thus needing less welding. Two rotary pocket feeders, each with at least one shaft extending parallel to the long side, are arranged directly under the rectangular section, enabling a uniform feed from the bin. The use of two rotary pocket feeders with this design directly under the bin does not destroy the even feed of material through the bin part, which otherwise is experienced from using conventional feed screws that feed material in a transverse direction from the bin outlet. The bin does not need to have a complex bin design which converges to a small circular inlet to a conventional rotary pocket feeder.

The bin arrangement is for collecting and discharging smaller ligno-cellulosic material. The bin has a transition part from a circular section of the bin and downwardly to a rectangular section with a long and short side of the rectangular section. The transition part could be built with few wall segments, thus needing less welding. Two rotary pocket feeders, each with at least one shaft extending parallel to the long side, are arranged directly under the rectangular section, enabling a uniform feed from the bin. The use of two rotary pocket feeders with this design directly under the bin does not destroy the even feed of material through the bin part, which otherwise is experienced from using conventional feed screws that feed material in a transverse direction from the bin outlet. The bin does not need to have a complex bin design which converges to a small circular inlet to a conventional rotary pocket feeder.

The invention relates to a discharge screw arrangement (12) for discharging lignocellulosic material (7) from a lignocellulosic treatment reactor (1) and comprises a discharge screw (10), a feeder pipe (11) and a blow pipe (5), the discharge screw being accommodated in and rotatably arranged inside the feeder pipe and being configured to mechanically transport the lignocellulosic material in a longitudinal direction along a rotational axis of the discharge screw through the feeder pipe towards a downstream end (14) of the feeder pipe, which discharge screw arrangement is configured to allow steam to flow through the feeder pipe to help transporting the lignocellulosic material in the longitudinal direction along through the feeder pipe and out of the feeder pipe through an outlet nozzle (24) arranged in a side wall of the feeder pipe (11) at the downstream end of the feeder pipe and into the blow pipe, wherein the discharge screw arrangement further comprises a material spreader (20), which is rotatably arranged at the downstream end of the feeder pipe and is configured to transport the lignocellulosic material in a radial direction, perpendicular to a rotational axis of the material spreader, towards the outlet nozzle, which is arranged peripherally of the material spreader, and out of the feeder pipe through the outlet nozzle and into the blow pipe.

The invention relates to a discharge screw arrangement (12) for discharging lignocellulosic material (7) from a lignocellulosic treatment reactor (1) and comprises a discharge screw (10), a feeder pipe (11) and a blow pipe (5), the discharge screw being accommodated in and rotatably arranged inside the feeder pipe and being configured to mechanically transport the lignocellulosic material in a longitudinal direction along a rotational axis of the discharge screw through the feeder pipe towards a downstream end (14) of the feeder pipe, which discharge screw arrangement is configured to allow steam to flow through the feeder pipe to help transporting the lignocellulosic material in the longitudinal direction along through the feeder pipe and out of the feeder pipe through an outlet nozzle (24) arranged in a side wall of the feeder pipe (11) at the downstream end of the feeder pipe and into the blow pipe, wherein the discharge screw arrangement further comprises a material spreader (20), which is rotatably arranged at the downstream end of the feeder pipe and is configured to transport the lignocellulosic material in a radial direction, perpendicular to a rotational axis of the material spreader, towards the outlet nozzle, which is arranged peripherally of the material spreader, and out of the feeder pipe through the outlet nozzle and into the blow pipe.

The present disclosure is directed to an apparatus and method for processing lignocellulosic material. The apparatus includes a vessel having a fluid separation plate disposed therein, a fluid circulating system in fluid communication with the vessel and various component parts including nozzles, valves, lines and pumps as needed for discharging processed lignocellulosic materials.

The present disclosure is directed to an apparatus and method for processing lignocellulosic material. The apparatus includes a vessel having a fluid separation plate disposed therein, a fluid circulating system in fluid communication with the vessel and various component parts including nozzles, valves, lines and pumps as needed for discharging processed lignocellulosic materials.