Vertical digester and high-yield chemi-mechanical pulp system

Abstract

The invention relates to a vertical digester and a high-yield chemi-mechanical pulp system.The vertical digester comprises a vertically-arranged digester body, the digester body is in a big-end-down barrel shape, a feeding port is formed in the upper portion of the digester body, a discharging screw is arranged at the bottom of the digester body and transversely arranged, a stirring mechanism is arranged at the position, above the discharging screw, in the digester body, and a steam inlet is formed in the bottom of the digester body; and the steam inlet is communicated with the groove body where the discharging screw is located. According to the vertical digester disclosed by the invention, materials enter from the upper part and fall down, and steam enters from the bottom of the digester body and flows upwards, so that the steaming effect on the materials can be improved. The digester is vertical, the upper portion of the vertical digester is connected with a T-shaped pipe, the bottom of the vertical digester is provided with a transversely-arranged discharging spiral used for being connected with a high-temperature wire machine, the overall structure of the system is simplified, and the occupied space is small.

Description

Technical Field

[0001] The invention relates to a chemical-mechanical pulping system in the pulping industry, and in particular to a vertical cooking pot and a high-yield chemical-mechanical pulping system. Background Art

[0002] The large-scale chemical mechanical pulping industry, which uses bamboo chips, wood and other forestry residues as pulping raw materials, is increasingly emerging. High-temperature silk-forming machines (thermal mills, high-pressure mills, etc.) are key equipment in the chemical mechanical pulping industry, used to separate and broom wood chips and other forestry residues, and then form qualified pulp after subsequent dosing reactions. Whether the operation effect of the high-temperature silk-forming machine (thermal mill, high-pressure mill, etc.) is stable, whether the wood chips are separated and broomed thoroughly, and whether the fiber yield is high are directly related to the wood chips that enter the high-temperature silk-forming machine (thermal mill, high-pressure mill, etc.) and are processed by the chemical mechanical pulping system.

[0003] For example, the invention patent with announcement number CN114318918B (the prior patent of the applicant in this case) discloses a chemical-mechanical pulp preparation process, which mainly involves steam preheating equipment, screw conveying equipment, and cooking equipment. The washed wood chips are steam preheated in the steam preheating equipment, and the preheated and softened wood chips are screw conveyed to the cooking equipment by the screw conveying equipment for cooking. During the cooking process, the wood chips and the added chemicals are fully mixed and absorbed; the cooked wood chips enter the high-temperature silk-forming equipment for high-temperature silk-forming. The cooking equipment used in this process is a horizontal cooking tube, and a screw feeder and a T-tube are provided in front of the horizontal cooking tube for preliminary extrusion of wood and blocking steam; a balance bin and a buffer tube are provided behind the horizontal cooking tube for precise feeding and to compensate for the pipe mouth error caused by thermal expansion and contraction of the equipment, and a side feeding screw is also required to block the steam pressure to prevent it from entering the high-temperature silk-forming machine. The entire system has many equipment and control points, and the system occupies a large space, and the construction cost is relatively high. The wood chips in the horizontal cooking tube are cooked while moving under the drive of the spiral blades. The wood chips cannot fill the entire cooking tube, and the steam entering the cooking tube tends to move upward, resulting in uneven cooking of the wood chips in the cooking tube. When these unevenly cooked wood chips enter the high-temperature silk-making machine, the high-temperature silk-making machine will run unstably, thereby affecting the quality of the pulp and the fiber yield. Summary of the invention

[0004] The purpose of the present invention is to provide a vertical cooking pot and a high-yield chemimechanical pulping system using the vertical cooking pot to solve the problems of uneven cooking of wood chips in the above-mentioned horizontal cooking equipment and large space occupied by the existing chemimechanical pulping system.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] The vertical cooking pot comprises a pot body arranged vertically, which is in the shape of a cylinder with a small top and a large bottom. The upper part of the pot body is a feed inlet, and a discharge spiral is arranged at the bottom of the pot body. The discharge spiral is arranged horizontally. A material shifting mechanism is arranged above the discharge spiral in the pot body, and a steam inlet is arranged at the bottom of the pot body, which is connected to the trough body where the discharge spiral is located.

[0007] Furthermore, the material-moving mechanism comprises at least two arc-shaped plates, and the arc-shaped plates are arranged at intervals on a vertically arranged rotating shaft.

[0008] Furthermore, the center of the arc-shaped plate and the center of the trough body are arranged correspondingly.

[0009] Furthermore, there are two arc-shaped plates distributed along the circumferential direction of the rotating shaft. The arc-shaped plates are used to move the materials, and the direction of rotation of the moving materials is opposite to the discharging direction of the discharging spiral.

[0010] Furthermore, a T-shaped paddle is provided on the upper portion of the rotating shaft.

[0011] Furthermore, the discharging spiral is offset from the bottom of the pot body, and a ventilation slit is provided on the trough body, the ventilation slit is connected to the steam inlet, and the ventilation slit is close to the center of the bottom of the pot body.

[0012] Furthermore, a sealing compensation assembly is connected to the end of the discharging screw, and the sealing compensation assembly includes two connecting flanges, a compensation sleeve and two groups of packing seals. The two connecting flanges are respectively connected to the discharging screw and the high-temperature silk-making machine. The compensation sleeve is located between the two connecting flanges. The two groups of packing seals are respectively located at the connection between the connecting flange and the discharging screw and at the connection between the connecting flange and the high-temperature silk-making machine.

[0013] Furthermore, the two connecting flanges are respectively defined as a first flange and a second flange. The second flange is used to connect to the high-temperature silk-making machine. An end of the second flange facing the compensation sleeve is provided with a stopper to cooperate with the compensation sleeve.

[0014] A high-yield chemical mechanical pulping system comprises a screw feeder and a T-tube, wherein the screw feeder is connected to the T-tube, and also comprises a vertical cooking pot as described above, wherein the lower part of the T-tube is connected to the upper part of the vertical cooking pot.

[0015] Furthermore, a bulking mechanism is provided on the side of the T-tube opposite to the screw feeder. The bulking mechanism includes an anti-backspray cone cap located inside the T-tube and a cylinder fixed outside the T-tube. The anti-backspray cone cap is driven by the cylinder.

[0016] Beneficial effects of the present invention:

[0017] The present invention provides a vertical cooking pot, wherein materials enter from the upper part and fall downward, and steam enters from the bottom of the pot body and moves upward, thereby improving the cooking effect on the materials and thus improving the final fiber yield. The cooking pot is vertical, the upper part of the vertical cooking pot is connected to a T-shaped pipe, and the bottom of the vertical cooking pot is provided with a horizontally placed discharge screw for connecting with a high-temperature silk-making machine. The overall structure of the system is simplified, the space occupied is small, and the investment is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the high-yield chemimechanical pulping system of the present invention;

[0019] Figure 2 This is a structural view of the bottom of the vertical cooking pot and the discharge spiral;

[0020] Figure 3 It is a schematic diagram of the bottom of a vertical cooking pot;

[0021] Figure 4 It is a schematic diagram of the structure of the sealing compensation component (cutaway view).

[0022] The names corresponding to the marks in the figure are:

[0023] 1. Screw feeder; 2. T-tube; 31. Cylinder; 32. Anti-backspray cone cap; 4. Vertical cooking pot; 41. Steam inlet; 5. Material shifting mechanism; 51. Arc plate; 52. T-type shifting piece; 6. Discharging screw; 61. Trough body; 62. Ventilation gap; 7. Sealing compensation assembly; 71. First flange; 72. Second flange; 721. Stopper; 73. Compensation sleeve; 74. Packing seal. DETAILED DESCRIPTION

[0024] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0025] Embodiments of the high-yield chemimechanical pulping system of the present invention:

[0026] like Figure 1-Figure 4As shown, the high-yield chemical pulping system includes a screw feeder 1, a T-tube 2, and a vertical cooking pot 4. The screw feeder 1 is connected to one side of the T-tube 2, and the lower part of the T-tube 2 is connected to the upper part of the vertical cooking pot 4. A bulking mechanism is provided on the side of the T-tube 2 opposite to the screw feeder 1. The bulking mechanism includes a back-spraying prevention cone cap 32 located in the T-tube 2 and a cylinder 31 fixed outside the T-tube 2. The back-spraying prevention cone cap 32 is driven by the cylinder 31 to move laterally. The structure and principle of the screw feeder 1 and the T-tube 2 are basically consistent with the prior art. The main improvement of this case lies in the structure of the vertical cooking pot.

[0027] The vertical cooking pot 4 comprises a pot body arranged vertically, which is cylindrical with a small top and a large bottom (the upper diameter is smaller than the lower diameter). The upper part of the pot body is a feed inlet, and the design of a small top and a large bottom prevents the material from bridging inside the pot body and not falling downward. Figure 2 As shown, a discharging screw 6 is provided at the bottom of the pot body, and the discharging screw 6 is arranged horizontally. A material-discharging mechanism 5 is provided above the discharging screw 6 in the pot body, and the material-discharging mechanism 5 includes two arc plates 51, and the arc plates 51 are arranged at intervals on a vertically arranged rotating shaft. The two arc plates 51 are distributed along the circumferential direction of the rotating shaft, and the center of the arc plate 51 is arranged correspondingly to the center of the trough body 61. When the arc plate 51 rotates, it is used to displace the material, and the direction of rotation of the discharging material is opposite to the discharging direction of the discharging screw 6. The arc plate 51 drives the material to gather toward the middle of the material-discharging mechanism 5, so that more and faster materials enter the trough body 61 of the discharging screw 6.

[0028] Furthermore, a T-shaped paddle 52 is provided on the upper part of the rotating shaft to prevent the material from piling up above the rotating shaft of the arc plate 51. In combination with the arc plate 51, the material entering the groove 61 of the discharging screw 6 is more uniform, thereby improving the stability of the discharging screw 6.

[0029] Figure 3 As shown, a steam inlet 41 is provided on one side of the bottom of the pot body, and high-temperature, high-pressure steam enters from the steam inlet 41. The bottom of the pot body is closed and can withstand a certain high pressure. The discharging screw 6 is offset from the bottom of the pot body, and a vent 62 is provided on the groove body 61. The vent 62 is connected to the steam inlet 41, and the vent 62 is close to the center of the bottom of the pot body. The high-pressure, high-temperature steam entering from the vent 62 can be quickly spread around the vertical cooking pot 4 to ensure the consistency of the cooking of the internal and external materials. The steam enters from the bottom of the pot body to ensure that the steam is always in full contact with the material, the cooking is thorough and the steam is saved.

[0030] Figure 4As shown, the end of the discharge screw 6 is connected with a sealing compensation component 7, which connects the discharge screw 6 to a high-temperature silk-making machine (thermal mill or high-pressure mill, etc.). The sealing compensation component 7 includes two connecting flanges, a compensation sleeve 73 and two groups of packing seals 74. For ease of description and understanding, the two connecting flanges are defined as a first flange 71 and a second flange 72. The first flange 71 is connected to the discharge screw 6, and the second flange 72 is used to connect to the high-temperature silk-making machine. The compensation sleeve 73 is located between the two connecting flanges, and the two groups of packing seals 74 are respectively located at the connection between the first flange 71 and the discharge screw 6 and at the connection between the second flange 72 and the high-temperature silk-making machine, that is, the inner circumferential walls of the two connecting flanges are provided with sealing ring grooves, and a gap is formed between the outer circumference of the compensation sleeve 73 for the packing seal 74 to be installed. A stop 721 is provided at one end of the second flange 72 facing the compensation sleeve 73, which cooperates with one end of the compensation sleeve 73 to prevent the compensation sleeve 73 from entering the high-temperature silk-making machine along the material discharge direction. The other end of the compensation sleeve 73 is not limited, so the non-rigidly connected compensation sleeve 73 can achieve sliding compensation. The chemical mechanical pulp system of the present invention has a high temperature during operation, and there is thermal expansion and contraction, which will cause the relative position of the two connecting flanges to change radially and axially. The compensation sleeve 73 will slide or tilt with the position change, and the two sets of packing seals 74 will eliminate the leakage caused by the change.

[0031] The working principle of the high-yield chemimechanical pulping system of the present invention is as follows:

[0032] The cleaned wood chips enter the screw feeder 1 from the feed port, and after the initial squeezing of the variable diameter screw, the excess water is removed and a plug is formed. The plug enters the T-tube 2 forward and pushes the anti-reverse spray cone cap 32 in the T-tube 2. The anti-reverse spray cone cap 32 is driven by the cylinder 31 and maintains a certain pressure against the plug. The plug is dispersed under the action of the anti-reverse spray cone cap 32 and falls into the vertical cooking pot 4 below. When the plug is insufficient, the discharge port of the screw feeder 1 can be closed to prevent a large amount of steam in the system from spraying back. The high-pressure steamed material falling into the vertical cooking pot 4 enters the trough of the discharge screw 6 under the action of the material-digging mechanism 5, and is squeezed to form a plug under the action of the variable diameter screw of the discharge screw 6. The plug passes through the sealing compensation component 7 and enters the subsequent high-temperature silk-making machine.

Claims

1. Vertical cooking pot, characterized by: The utility model comprises a vertically arranged pot body, which is in the shape of a cylinder with a small top and a large bottom. The upper part of the pot body is a feed inlet, the bottom of the pot body is provided with a discharge screw, the discharge screw is arranged horizontally, a material shifting mechanism is arranged above the discharge screw in the pot body, a steam inlet is arranged at the bottom of the pot body, and the steam inlet is connected with the trough body where the discharge screw is located.

2. The vertical cooking pot according to claim 1, characterized in that: The material-shifting mechanism comprises at least two arc-shaped plates, which are arranged at intervals on a vertically arranged rotating shaft.

3. The vertical cooking pot according to claim 2, characterized in that: The center of the arc plate and the center of the trough body are arranged correspondingly.

4. The vertical cooking pot according to claim 2, characterized in that: There are two arc plates distributed along the circumferential direction of the rotating shaft. The arc plates are used to move the materials, and the direction of rotation of the moving materials is opposite to the discharging direction of the discharging spiral.

5. The vertical cooking pot according to claim 4, characterized in that: A T-shaped paddle is arranged on the upper part of the rotating shaft.

6. The vertical cooking pot according to claim 1, characterized in that: The discharging spiral is offset from the bottom of the pot body, and a ventilation slot is provided on the trough body. The ventilation slot is connected to the steam inlet, and the ventilation slot is close to the center of the bottom of the pot body.

7. The vertical cooking pot according to claim 1, characterized in that: The end of the discharging screw is connected with a sealing compensation assembly, which includes two connecting flanges, a compensation sleeve and two sets of packing seals. The two connecting flanges are respectively connected to the discharging screw and the high-temperature silk-making machine. The compensation sleeve is located between the two connecting flanges. The two sets of packing seals are respectively located at the connection between the connecting flange and the discharging screw and at the connection between the connecting flange and the high-temperature silk-making machine.

8. The vertical cooking pot according to claim 7, characterized in that: The two connecting flanges are respectively defined as a first flange and a second flange. The second flange is used to be connected to a high-temperature silk-making machine. One end of the second flange facing the compensation sleeve is provided with a stopper to cooperate with the compensation sleeve stopper.

9. A high-yield chemical-mechanical pulping system, comprising a screw feeder and a T-tube, wherein the screw feeder is connected to the T-tube, and is characterized in that: It also comprises a vertical cooking pot as claimed in any one of claims 1 to 8, wherein the lower part of the T-tube is connected to the upper part of the vertical cooking pot.

10. The high-yield chemimechanical pulping system according to claim 9, characterized in that: A bulking mechanism is provided on one side of the T-tube opposite to the screw feeder. The bulking mechanism comprises an anti-backspray cone cap located inside the T-tube and a cylinder fixed outside the T-tube. The anti-backspray cone cap is driven by the cylinder.

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