RU2844525C1 - Device for washing of cellulose mass - Google Patents

Abstract

FIELD: production of cellulose.

SUBSTANCE: invention relates to process equipment, namely to a device for processing cellulose pulp, which can find application in the pulp and paper industry for washing cellulose and/or wood pulp. Device comprises a hollow housing forming a pressure compartment for a mass flow consisting of a fibrous mass in a washing liquid, located inside the housing a hole for supplying the mass to the inlet zone and an opening for its outlet, a cylindrical washing screen located inside the housing, which creates a barrier for passage of the fibrous mass from one side of the screen to its opposite side and ensuring passage through it of washing liquid into liquid collection chamber connected to lower part of housing, system for introducing a flushing liquid displacing and replacing the flushing liquid passing through the flushing screen, fixed above the cylindrical washing grid of the shell with a concave profile, which are mounted on rollers fixed on shafts to ensure rotation, wherein said shafts are rigidly secured via bearing housings to the carcass extending through the entire housing bottom part and rigidly secured thereto. Side part of housing is equipped with at least two sealed opening hatches with possibility of opening and maintenance of device, mass supply hole has inner slot and installed in it cutting element, inner surface of the cylindrical washing mesh is provided with blades rigidly fixed thereon, ensuring the movement of the fibrous mass towards the outlet during the rotation of the shafts, holes in the cylindrical washing grid are made of rectangular shape with size of 70-90 mm with inclination of 5-6 degrees along the axis of rotation in the direction of flowing mass supply, flushing liquid introduction system is made in the form of at least three branch pipes fixed on the housing and supplying the washing liquid under pressure, at least two of which pass in the upper part inside the cylindrical washing grid and are intended for the washing liquid supply through the angular nozzles towards the fibrous mass flow through every 20-50 cm, and at least one branch pipe extends between the cylindrical washing screen and the housing with the nozzles arranged every 50-100 mm at a right angle to the cylindrical washing screen for cleaning of stuck fibre.

EFFECT: creation of efficient and easily maintained device for washing of cellulose mass.

5 cl, 5 dwg

Description

The invention relates to process equipment for processing cellulose pulp and can find application in the pulp and paper industry for washing cellulose and/or wood pulp.

A device for washing fibrous mass is known (USSR A.S. No. 1477799, IPC D21C 9/00, published on 07.05.1989, Bulletin No. 17), consisting of a cylindrical body with branches for feeding and removing fibrous mass and branches for feeding and removing washing liquid. A hollow distributor of washing liquid is installed inside the body along its axis, made in the form of perforated plates connected to each other and forming a closed volume, installed parallel to each other and communicating with branches for feeding washing liquid. A chamber for collecting washing liquid with filter screens is installed in the upper and lower parts of the body, forming a closed volume with the body, communicating with branches for removing washing liquid. In this case, the grids are parallel to each other, and flat guide plates are installed on the surface of the distributor and the washing liquid collection chamber, located parallel to each other along the axis of the housing and made of different lengths.

The disadvantage of this device is the unreliability of the design and low efficiency of the device due to clogging of the filter screens.

A device is known for squeezing and washing fibrous mass (USSR A.S. No. 1645324, IPC D21C 9/06, published 30.04.1991, Bulletin No. 16), comprising a housing with pipes for feeding fibrous mass, wash water and mass outlet, a perforated drum, support posts on which the housing is mounted, blades inserted into drum grooves, rods secured to the ends of the blades, forks that are secured to the rods, rollers movably secured to the axes of the forks, rims on which the rollers rest by means of springs, guide bushings in which the rods move, seals for the rod, seals between the surface of the drum and the housing, end covers with openings for removing the filtrate and a frame to which the rims are secured.

The disadvantage of this device is the unreliability of the design and low efficiency of the device due to clogging of the perforated drum.

The closest to the proposed technical solution is a device for washing wood fiber pulp (RU Patent No. 2095502, IPC D21C 9/02, IPC D21D 1/40, published on 10.11.1997), comprising a hollow body, a stationary washing grid, a chamber for collecting liquid formed by the grid and the body, means for feeding a flow of pulp and washing liquid and removing liquid passing through the washing grid, there is a rotating means, which is a rotor for providing high-frequency low-amplitude pulses in the pulp passing along the grid, having a cylindrical surface, and the washing grid is made in the form of a shell. The cylindrical surface of the rotor has a large number of outward protrusions. The protrusions have a hemispherical shape.

The disadvantage of this device is its insufficient efficiency in the event of long fibers being washed and clinging to the washing mesh, as well as the difficulty of maintenance if necessary.

The technical result of the proposed invention is the creation of an efficient and easily maintained device for washing cellulose pulp.

The technical solution is a device for washing cellulose pulp, containing a hollow body, forming a pressure section for a flow of pulp, consisting of fibrous pulp in a washing liquid, an opening located inside the body for feeding the pulp into the input zone and an opening for its output, a cylindrical washing mesh located inside the body, creating a barrier for the passage of fibrous pulp from one side of the mesh to its opposite side and ensuring the passage of washing liquid through it into a liquid collection chamber connected to the lower part of the body, a system for introducing washing liquid, displacing and replacing the liquid passing through the washing mesh, shells with a concave profile fixed above the cylindrical washing mesh, which are mounted on rollers fixed on shafts to ensure rotation, wherein the shafts are rigidly fixed through bearing housings to a frame passing through the entire lower part of the body and rigidly fixed to it.

What is new is that the side part of the housing is equipped with at least two sealed opening hatches with the ability to open and service the device, the hole for feeding the mass has an internal groove and a cutting element installed in it, the inner surface of the cylindrical washing mesh is equipped with blades rigidly fixed to it, providing movement of the fibrous mass towards the outlet when the shafts rotate, the openings in the cylindrical washing mesh are made rectangular in shape with a size of 70-90 mm with an inclination of 5-6 degrees along the axis of rotation in the direction of feeding the current mass, the system for introducing the washing liquid is made in the form of at least three pipes fixed to the housing and supplying the washing liquid under pressure, at least two of which pass in the upper part inside the cylindrical washing mesh and are intended to supply the washing liquid through corner nozzles towards the flow of the fibrous mass every 20-50 cm, and at least one pipe passes between the cylindrical washing mesh and the housing with the arrangement nozzles every 50-100 mm at a right angle to the cylindrical washing mesh to clean out stuck fiber.

What is also new is that an additional mesh with micro-holes, the size of which can vary depending on the density of the fibrous mass, can be installed on top of the cylindrical washing mesh, using metal clamps and/or ties.

What is also new is that the liquid collection chamber can be equipped with a heating coil and a washing liquid recirculation system.

What is also new is that the cylindrical washing mesh can be made in the form of separate sections with rigid shells fixed at the ends and connected to each other with detachable joints.

What is also new is that, depending on the requirements for the characteristics and cleanliness of the heavily contaminated washed fibre, water with added surfactants can be used as the washing liquid.

Fig. 1 shows a general view of the invention from the left.

Fig. 2 – front view.

Fig. 3 is a front view in section A-A.

Fig. 4 is a left-hand view in section A-A.

Fig. 5 is a rear view in section B-B.

A device for washing cellulose pulp, comprising a hollow body 1 (Fig. 1), forming a pressure section for a flow of pulp consisting of fibrous pulp in a washing liquid (not shown). The body 1 has a square shape and can be made of any rigid material, for example, welded from metal. For feeding and exiting the cellulose pulp into the body 1 and from the body 1, respectively, an opening for feeding the pulp into the input zone 2 (Fig. 2) and an opening for its exit 3 (Fig. 3) are located on it on opposite sides. In the opening for feeding the pulp into the input zone 2, an internal groove is located (not shown), in which a cutting element 4 is located (Fig. 2). The cutting element 4 is a round shell (shown conditionally), proportionate to the size of the entry into the internal groove of the opening for feeding the pulp 2, and knives 5 fixed inside it (Fig. 2). The round shell is made of metal, and the knives 5 (Fig. 2) can be welded and/or glued inside in the shape of an X and/or in any other known way that ensures the separation of the incoming cellulose mass into parts. Also located inside the housing 1 is a cylindrical washing mesh 6 (Fig. 4), creating a barrier for the passage of the fibrous mass from one side of the mesh to its opposite side and ensuring the passage of the washing liquid through it. For ease of maintenance and faster cleaning of the elements, the cylindrical washing mesh 6 (Fig. 4) is made in the form of separate sections with rigid shells 7 (Fig. 4) fixed at the ends, which are connected to each other by detachable joints (not shown). The openings in the cylindrical washing mesh 6 are made rectangular in shape, 70-90 mm in size, with an inclination of 5-6 degrees along the axis of rotation in the direction of feeding the current mass. The shell 7 can be made of a rigid material, for example, metal, and the detachable connection between the two shells is provided by any known method that does not interfere with the rotational movements of the shell 7, for example, using a tenon-groove connection. Additionally, on top of the cylindrical washing mesh 6, on metal clamps and/or ties (not shown), an additional mesh with micro-holes (not shown) is installed, the size of which can vary depending on the density of the fibrous mass. For example, a woven stainless steel mesh 12X18N10T with a hole size of 0.5 mm x 0.25 mm. A liquid collection chamber 8 (Fig. 4) is connected to the lower part of the housing 1. In order to intensify the washing of the cellulose pulp and for the need to operate the pulp washing unit in the winter, the liquid collection chamber 8 (Fig. 4) is equipped with a coil-heat exchanger for heating (shown conditionally) and a washing liquid recirculation system (not shown). Depending on the requirements for the characteristics and purity of the heavily contaminated cellulose fiber to be washed, water with the addition of surfactants can be used as a washing liquid. In other cases, water is used as a washing liquid. For displacing and replacing the washing liquid passing through the cylindrical washing mesh 6 (Fig. 4), the device comprises a system for introducing washing liquid 9 (Fig. 3), which consists of at least 3 pipes fixed to the housing 1 and supplying washing liquid under pressure created by a pump (not shown), at least two 10 (Fig. 3) of which pass in the upper part inside the cylindrical washing mesh 6 (Fig. 4) and are intended to supply washing liquid through angular nozzles 11 (Fig. 4) towards the flow of cellulose mass every 20-50 cm, and at least one pipe 12 (Fig. 3) passes between the cylindrical washing mesh 6 and the housing 1 with the nozzles arranged every 50-100 mm at a right angle (not shown) relative to the cylindrical washing mesh 6 for cleaning from stuck fiber (not shown). To ensure rotation, the shells 7, rigidly fixed above the cylindrical washing mesh 6, have a concave profile for the possibility of installation on rollers 13 (Fig. 5). Rollers 13 (Fig. 5) are rigidly fixed on shafts 14 (Fig. 5) to ensure rotation and transmission of torque to shells 7, wherein the shafts are rigidly attached through bearing housings to frame 15 (Fig. 5). Rollers 13 (Fig. 5) can be made of any material that provides sufficient rigidity and friction to transmit torque to shells 7, for example, rubber. The dimensions of the rollers 7 are selected in such a way as to ensure their fit into the concave profile of shells 7. Frame 15 (Fig. 5) passes through the entire lower part of housing 1 and is rigidly fixed to it. The frame 15 can be made of any material that provides the necessary strength and durability, for example, from profile metal pipes. The side part of the body 1 is provided with at least two sealed opening hatches 16 (Fig. 1) with the possibility of opening and servicing the device. The size of the hatches 16 is selected in such a way as to ensure free access of the service personnel to the necessary section of the cylindrical washing mesh 6. The material, methods of fastening and opening the hatches 16 can be made in any known way. The authors do not claim this. To ensure the movement of the fibrous mass towards the outlet opening 3 during rotation of the shafts 14 (Fig. 5), the inner surface of the cylindrical washing mesh 6 (Fig. 4) is provided with blades 17 (Fig. 4) rigidly fixed to it. The blades can be made of any known material that provides the necessary strength for the radial movement of the pulp towards the outlet opening 3 during rotation of the cylindrical washing mesh 6. The shafts 14 (Fig. 5) rotate due to the drive installed outside the housing 1. The drive can be made in any known way. For example, a rotor system or a chain. The authors do not claim this.

Structural elements, technological connections and seals that do not affect the performance of the device are not shown or are shown conditionally.

The device for washing cellulose pulp operates as follows.

Before the flushing process, a pipeline from a container with clean water (not shown) is connected to the system for introducing flushing liquid 9 and the liquid collection chambers 8 are filled. Then, a pipeline leading from the liquid collection chamber 8 is connected to the system for introducing flushing liquid 9, creating the necessary pressure with a pump (not shown). The pulp enters through the pulp feed pipeline (not shown) and enters the device through the opening 2 for feeding the pulp in chopped form through the cutting element 4. Then the drive (shown conditionally) is started, ensuring the rotation of the shafts 14. The rollers 13, mounted on the shafts 14, in contact with the inner part of the concave profile of the shells 7, rotate and through the shells 7 transmit rotation to the cylindrical washing mesh 6, thereby producing the translational movement of the blades 17. The blades 17 direct the movement of the pulp along the axis of the cylindrical washing mesh of the opening for its outlet 3. Under the pressure of the washing liquid from the corner nozzles 11 towards the flow of the pulp, active washing occurs with simultaneous distribution over the cylindrical washing mesh 6 and the blades 17. The washing liquid through the openings in the cylindrical The washing mesh flows into the liquid collection chamber 8, is heated by the heat exchanger coil, in which hot steam, hot water, etc. circulate, and is returned to the system for introducing the washing liquid 9. The authors do not claim this. Simultaneously with the supply of washing liquid through the corner nozzles 11, it is supplied to the nozzles located at a right angle to the cylindrical washing mesh to free the holes from caught cellulose fibers. The washed cellulose mass enters through the opening 3 into the container for collecting the washed cellulose mass (not shown). To prevent the cellulose mass from entering the liquid collection chamber 8, an additional mesh with micro-holes (not shown) is installed on top of the cylindrical washing mesh 6. To service the pulp washing device, it is necessary to disconnect the pulp feed pipeline (not shown) from the pulp feed opening 2, stop the rotation of the shafts 14 by stopping the drive (not shown), stop the supply of washing liquid to the system for introducing washing liquid 9 and open the hatches 16. Cleaning and maintenance are carried out in any known way.

The proposed device for washing cellulose pulp is

effective due to the presence of a cutting tool for preliminary cutting of the cellulose mass, blades that ensure the movement of the fibrous mass towards the outlet by means of rotation, a modified shape of the holes in the cylindrical washing mesh for better contact with the cellulose mass, an additional mesh with micro-holes, supply of washing liquid towards the flow and at a right angle to the cylindrical washing mesh, the possibility of heating and using water with the addition of surfactants as a washing liquid, and ease of maintenance is ensured by the presence of hatches through which individual sections of the cylindrical washing mesh can be serviced.

Claims (5)

1. A device for washing cellulose pulp, comprising a hollow housing forming a pressure section for a flow of pulp consisting of fibrous pulp in a washing liquid, an opening located inside the housing for feeding the pulp into an inlet zone and an opening for its outlet, a cylindrical washing mesh located inside the housing, creating a barrier for the passage of fibrous pulp from one side of the mesh to its opposite side and ensuring the passage of washing liquid through it into a liquid collection chamber connected to the lower part of the housing, a system for introducing washing liquid, displacing and replacing the washing liquid passing through the washing mesh, shells with a concave profile fixed over the cylindrical washing mesh, which are mounted on rollers fixed to shafts to ensure rotation, wherein the shafts are rigidly fixed through bearing housings to a frame passing through the entire lower part of the housing and rigidly fixed to it, characterized in that the side part of the housing is provided with at least two sealed opening hatches with the possibility of opening and servicing the device, the hole for feeding the mass has an internal groove and a cutting element installed in it, the inner surface of the cylindrical washing mesh is equipped with blades rigidly fixed to it, ensuring the movement of the fibrous mass towards the outlet when the shafts rotate, the holes in the cylindrical washing mesh are made rectangular in shape with a size of 70-90 mm with an inclination of 5-6 degrees along the axis of rotation in the direction of feeding the current mass, the system for introducing the washing liquid is made in the form of at least three pipes fixed to the body and supplying the washing liquid under pressure, at least two of which pass in the upper part inside the cylindrical washing mesh and are intended to supply the washing liquid through corner nozzles towards the flow of the fibrous mass every 20-50 cm, and at least one pipe passes between the cylindrical washing mesh and the body with the arrangement of nozzles every 50-100 mm at a right angle relative to the cylindrical washing mesh to clear stuck fibres. 2. A washing device according to item 1, characterized in that an additional mesh with micro-holes, the size of which varies depending on the density of the fibrous mass, is installed on top of the cylindrical washing mesh on metal clamps and/or ties. 3. A device for flushing according to any one of paragraphs 1 or 2, characterized in that the chamber for collecting liquid is equipped with a heating coil and a flushing liquid recirculation system. 4. A device for washing according to any of paragraphs 1, 2 or 3, characterized in that the cylindrical washing mesh is made in the form of separate sections with rigid shells fixed at the ends, which are connected to each other by detachable connections. 5. A device for flushing according to any one of paragraphs 1, 2, 3 or 4, characterized in that it is designed with the possibility of using water with the addition of surfactants as a flushing liquid.