Automatic densification buffer stock bin for pulping straw raw materials

Abstract

The invention relates to an automatic densification buffering stock bin for straw raw material pulping. The automatic densification buffering stock bin comprises a bin body, a feeding device, a discharging device, a densification pressurizing device and a conveying device. The conveying device is used for conveying straw raw materials in the bin body in the horizontal direction; the feeding device is arranged at the upper part of the bin body and is used for introducing straw raw materials to the upstream of the conveying device; the discharging device is arranged on the lower portion of the bin body, located on the downstream portion of the conveying device and used for discharging the densified straw raw materials out of the bin body. According to the automatic densification buffering stock bin for straw raw material pulping, at least one set of automatic densification device is integrally arranged in the bin body, and the pressurizing plate in the device periodically ascends and descends under the action of the driving mechanism; and when the material bin descends, the straw raw materials conveyed by the horizontal conveying device below the material bin are repeatedly compacted by means of the self weight of the material bin, so that the stacking density of the straw raw materials in the material bin and the actual storage volume per unit volume are effectively improved.

Description

Technical Field

[0001] This application relates to the technical field of pulp and paper making equipment, in particular to an automatic densifying buffer bin for straw raw material pulping. Background Art

[0002] In the prior art, with the increasing shortage of global forest resources and the continuous improvement of environmental protection awareness, using abundant crop straw resources (such as wheat straw, rice straw, corn stalks, bagasse, etc.) to replace wood as the main raw material for pulp and paper making has become an important way to achieve sustainable resource utilization, promote circular economy and reduce environmental pollution. As a large agricultural country, China produces a huge amount of crop straw every year, providing sufficient raw material guarantee for the straw pulp and paper industry. Currently, in modern straw pulp production processes, in order to ensure the long-term, continuous and stable operation of the entire production line (including processes such as stock preparation, cooking, washing, screening, bleaching, etc.), it is usually necessary to set up a buffer bin before the raw materials enter the main processing equipment (such as a digester). The main function of the buffer bin is to temporarily store a certain amount of straw raw materials to balance the unevenness or intermittency of the upstream incoming materials, and when the upstream equipment (such as chopping and dust removal equipment) has a short-term failure or maintenance, it can ensure that the downstream processes still have raw material supply, thereby avoiding the shutdown of the entire line due to raw material interruption and improving production efficiency and stability.

[0003] However, straw raw materials generally have physical characteristics such as light specific gravity, large volume, fluffy texture, and relatively large compression elasticity. Compared with other pulp raw materials such as wood chips, their natural bulk density is very low. This results in that when using traditional buffer bin designs, for example, simple square or circular silo structures, to achieve the buffer inventory (by weight) sufficient to support the stable operation of the production line for several hours or longer, the physical volume of the bin must be designed very large.

[0004] This design scheme of the traditional large-volume buffer bin brings significant disadvantages: First, the huge bin structure requires a large amount of building materials such as steel, and the manufacturing cost is high; second, large bins need to occupy a considerable amount of factory building or site area, which increases the infrastructure cost and layout difficulty for enterprises with tight land resources; third, fluffy straw is prone to "bridging" or "arching" in large bins, affecting the smooth feeding and discharging of straw raw materials, and additional auxiliary discharging devices may be required.

[0005] Therefore, for the buffer bin itself, how to effectively utilize its internal space during storage and increase the actual storage capacity per unit volume is still an urgent problem to be solved in the prior art. Summary of the Invention

[0006] To solve the above problems, the present application provides an automatically densifying and buffering silo for straw raw material pulping, which cyclically compresses straw by an internally integrated automatic densifying device, thereby reducing the volume, floor area and cost of the equipment.

[0007] To achieve the above object, the automatically densifying and buffering silo for straw raw material pulping designed in the present application includes a silo body, a feeding device, a discharging device, a densifying and pressurizing device and a conveying device; the conveying device is arranged at the bottom of the silo body and is used for horizontally conveying the straw raw material in the silo body; the feeding device is arranged at the upper part of the silo body and is used for introducing the straw raw material into the upstream of the conveying device; the discharging device is arranged at the lower part of the silo body and is located downstream of the conveying device, and is used for discharging the densified straw raw material from the silo body; the densifying and pressurizing device is arranged inside the silo body and is located above the conveying device, wherein the densifying and pressurizing device includes a pressure plate and a driving mechanism installed on the top of the silo body, and the driving mechanism is used for driving the pressure plate to lift periodically, and the pressure plate compresses the straw raw material conveyed by the conveying device directly below it by its own weight during the descending process.

[0008] A further solution is that the feeding device includes a distributing screw, and the distributing screw is provided with a plurality of distributing openings, and the plurality of distributing openings are spaced along the conveying direction of the conveying device and distributed on the top of the silo body.

[0009] A further solution is that there are four distributing openings.

[0010] A further solution is that there is one densifying and pressurizing device between every two adjacent distributing openings.

[0011] A further solution is that the driving mechanism includes:

[0012] a cylinder fixed on the top of the silo body;

[0013] two fixed sprockets rotatably fixed on the top of the silo body;

[0014] a guide rail fixed on the top of the silo body and extending along the length direction of the cylinder;

[0015] a moving sprocket pivotally connected to the end of the piston rod of the cylinder, and the moving sprocket slides along the guide rail under the drive of the cylinder;

[0016] a first chain, one end of which is fixed on the cylinder, and the other end is fixed on the pressure plate after passing around the moving sprocket and the fixed sprocket in sequence.

[0017] A further solution is that the conveying device is a horizontal chain plate conveyor, and its running speed is adjustable within 0 - 1.5 m / min.

[0018] A further solution is that the discharging device includes a discharging opening, a material pushing device, and a discharging screw. The discharging opening is arranged at the end of the conveying direction of the conveying device and extends perpendicular to the conveying direction of the conveying device. The material pushing device is used to push the straw raw material in the bin body towards the discharging opening, and the discharging screw is horizontally arranged in the discharging opening along the extending direction of the discharging opening.

[0019] A further solution is that the material pushing device includes a driving motor and a plurality of material pushing ratchets. The plurality of material pushing ratchets are arranged obliquely upward at intervals in the bin body along the direction from the discharging opening towards the feeding device. The driving motor synchronously drives the rotation of the plurality of material pushing ratchets through a set of second chains.

[0020] A further solution is that the discharging opening includes two oppositely arranged wall plates, and the two wall plates form a guiding opening with a gradually expanding opening. Among them, the wall plate close to the downstream of the conveying device is smoothly butted with the conveying device.

[0021] A further solution is that three material pushing ratchets are provided. Among them, the orthographic projections in the vertical direction of two adjacent material pushing ratchets in the vertical direction at least partially overlap.

[0022] The automatic densifying buffer bin for straw raw material pulping designed in this application integrates at least one set of automatic densifying device inside the bin body. By using the periodic lifting and lowering movement of the pressing plate in the device under the action of the driving mechanism, and relying on its own weight to repeatedly compact the straw raw material conveyed by the horizontal conveying device below when it descends, the stacking density of the straw raw material in the bin and the actual storage capacity per unit volume are effectively improved, and the buffering capacity of the bin is significantly enhanced to meet the requirements of the continuous and stable operation of the downstream production line. Furthermore, on the premise of ensuring the same buffering capacity, the physical volume, floor area, and corresponding equipment manufacturing cost and civil engineering investment required for the buffer bin can be reduced. Description of the Drawings

[0023] Figure 1 is a schematic plan view of the automatic densifying buffer bin for straw raw material pulping provided by an embodiment of this application.

[0024] Figure 2 is a schematic plan view of the driving mechanism provided by an embodiment of this application.

[0025] Wherein: silo body 10, feeding device 20, feeding spiral 21, feeding port 22, discharging device 30, discharging port 31, wall panel 311, material distributing device 32, driving motor 321, material distributing ratchet 322, second chain 323, discharging spiral 33, densifying and pressurizing device 40, pressure plate 41, driving mechanism 42, air cylinder 421, fixed sprocket 422, guide rail 423, moving sprocket 424, first chain 425, conveying device 50. Detailed implementation manners

[0026] The preferred embodiments of the present application will be described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present application, and are not used to limit the present application.

[0027] As Figure 1 、 Figure 2 shown, the automatic densifying buffer silo for straw raw material pulping described in this embodiment aims to effectively solve the problems in the prior art, such as the large design volume of the buffer silo, the wide occupation of site area, and the high equipment investment cost due to the inherent fluffy and low bulk density characteristics of the straw raw materials. The automatic densifying buffer silo mainly includes a silo body 10, a feeding device 20 provided at the upper part of the silo body 10, a discharging device 30 provided at the end of the silo body 10, at least one set of densifying and pressurizing devices 40, and a conveying device 50 provided at the bottom of the silo body 10, which serves as the bottom structure of the silo body 10 and is used for the conveying of straw raw materials.

[0028] Specifically, the conveying device 50 is arranged in the bottom area of the silo body 10, and a horizontal chain plate conveyor can be specifically adopted. The conveying device 50 not only bears the straw raw materials in the silo body 10, but also slowly and continuously conveys the straw raw materials from the upstream to the downstream in the horizontal direction at a preset and usually adjustable speed, so as to provide a stable straw raw material flow for subsequent densifying operations. In this embodiment, for example, the running speed of the horizontal chain plate conveyor can be adjusted within the range of 0 - 1.5 m / min.

[0029] The feeding device 20 is arranged at the upper part of the bin body 10 and is used to introduce the straw raw materials into the upstream of the conveying device 50. In this embodiment, the feeding device 20 preferably includes a distributing auger 21 which is provided with at least one feeding port for receiving the upstream incoming materials and a plurality of distributing ports 22. These distributing ports 22 are spaced along the conveying direction of the conveying device 50 on the top of the bin body 10, and can evenly distribute the received straw raw materials onto the surface of the upstream area of the lower conveying device 50, avoiding excessive local accumulation and being beneficial to subsequent compaction treatment. Correspondingly, the discharging device 30 is arranged at the lower part of the bin body 10 and is located downstream of the conveying device 50, and is used to discharge the densified straw raw materials from the bin body 10. Its main function is to efficiently discharge the straw raw materials which are conveyed by the conveying device 50 and compacted by the densifying and pressing device 40 from the bin body 10 and supply them to the subsequent working sections.

[0030] The densifying and pressing device 40 is arranged inside the bin body 10 and is located above the conveying device 50. As Figure 1 and Figure 2 shown, the densifying and pressing device 40 includes a pressing plate 41 and a driving mechanism 42 installed on the top of the bin body 10. The driving mechanism 42 is used to drive the pressing plate 41 to lift and lower periodically. During the descending process of the pressing plate 41, the straw raw materials conveyed by the conveying device 50 directly below it are compacted by its own weight.

[0031] As Figure 2 shown in a specific implementation manner, the driving mechanism 42 includes a cylinder 421 which is fixed on the top of the bin body 10; two fixed sprockets 422 which are rotatably fixed on the top of the bin body 10 and are used to change the direction of the chain; a guide rail 423 which is also fixed on the top of the bin body 10 and extends generally along the length direction of the cylinder 421 (i.e., the movement direction of the piston rod); a moving sprocket 424 which is pivotally connected to the end of the piston rod of the cylinder 421 and is configured to smoothly slide along the guide rail 423 under the drive of the cylinder 421; and a first chain 425. One end of the chain bypasses a moving sprocket 424 and two fixed sprockets 422, and the other end is finally reliably fixed on the pressing plate 41. During operation, when the piston rod of the cylinder 421 extends, the moving sprocket 424 moves along the guide rail 423. Through the cooperation of the first chain 425 and the fixed sprockets 422, the pressing plate 41 is lifted to a predetermined height; when the piston rod of the cylinder 421 retracts, the moving sprocket 424 moves in the reverse direction, and the first chain 425 becomes slack or is driven to lower. At this time, the pressing plate 41 can fall under the action of its own weight. During this descending process, the pressing plate 41 applies pressure to the fluffy straw raw materials being slowly conveyed by the conveying device 50 directly below it for effective compaction.

[0032] By controlling the pressing plate 41 through the driving mechanism 42 to perform such periodic lifting for repeated compaction actions, the stacking density of the straw raw materials in the bin 10 can be effectively increased. Under the condition of maintaining the same physical volume of the bin 10, more straw raw materials with a greater weight can be stored, thereby greatly improving the actual effective buffering capacity and space utilization efficiency of the buffer bin, effectively ensuring the continuous and stable operation of the downstream production line, and correspondingly reducing the requirements for the bin size and the related equipment manufacturing and civil engineering investment costs.

[0033] In some embodiments, such as Figure 1 、 Figure 2 shown, there are four feeding ports 22. The four feeding ports 22 distributed at intervals can spread the straw raw materials entering the bin 10 more evenly over a relatively long distance of the conveying device 50; and there is one of the densification and pressing devices 40 provided between every two adjacent feeding ports 22. The descending actions of the densification and pressing devices 40 are sequential. In the initial stage of feeding by the feeding device 20, the straw raw materials fall from the first feeding port 22 to form an initial layer, and then are preliminarily compacted by the first pressing plate 41. Subsequently, the new straw raw materials falling from the second feeding port 22 will cover (or be mixed with) the preliminarily compacted material layer. Then, this thickened material layer is further compacted by the second pressing plate 41. This operation of feeding - compaction - re - feeding - re - compaction has a better compaction effect compared to processing a very thick material layer at one time.

[0034] In some embodiments, such as Figure 1 、 Figure 2 shown, the discharging device 30 includes a discharging port 31, a material - shifting device 32, and a discharging screw 33. The discharging port 31 is arranged at the end of the conveying direction of the conveying device 50 and extends perpendicular to the conveying direction of the conveying device 50. The material - shifting device 32 is used to shift the straw raw materials in the bin 10 towards the discharging port 31. The material - shifting device 32 can adopt, for example, rotating rake teeth to sweep or push the materials from the end of the conveying device 50 into the discharging port 31 in an active and forced manner. And the discharging screw 33 is horizontally arranged in the discharging port 31 along the extending direction of the discharging port 31. Compared with simple gravity feeding, the discharging screw 33 is more reliable, not easily blocked, can better handle the straw with irregular shapes and possible compaction, and can also control the material flow rate discharged from the buffer bin by controlling the rotation speed of the discharging screw 33 to match the processing capacity or process requirements of the downstream equipment.

[0035] In some embodiments, such as Figure 1 、 Figure 2As shown, the material feeding device 32 includes a driving motor 321 and a plurality of material feeding ratchets 322. The plurality of material feeding ratchets 322 are arranged obliquely upward at intervals in the direction from the discharge port 31 towards the feeding device 20 within the bin body 10. The driving motor 321 synchronously drives the rotation of the plurality of material feeding ratchets 322 through a set of second chains 323. During operation, when the conveying device 50 conveys the straw raw materials to the end close to the discharge port 31, the rotating material feeding ratchets 322, with their obliquely upward position distribution, actively turn the material layer and effectively guide the materials into the discharge port 31, preventing the straw raw materials from caking and bridging.

[0036] Specifically, three material feeding ratchets 322 are provided. Among them, the orthographic projections in the vertical direction of two adjacent material feeding ratchets 322 in the vertical direction at least partially overlap. In this way, the action areas of the three material feeding ratchets 322 are not interrupted in the vertical direction, and can better disturb and stir the straw raw materials into the discharge port 31.

[0037] In some embodiments, as Figure 1 , Figure 2 shown, the discharge port 31 includes two oppositely arranged wall plates 311, and the two wall plates 311 form a guiding port with a gradually expanding opening. Among them, the wall plate 311 close to the downstream of the conveying device 50 is smoothly butted with the conveying device 50. The gradually expanding opening means that the end of the discharge port 31 where the materials are received at the entrance is wider than its internal channel, forming a flared or funnel-shaped entrance to guide the straw raw materials to gather at the center of the discharge port 31 and enter the action area of the discharge screw 33, and also reducing the risk of materials being crowded, bridged or blocked at the entrance.

[0038] The automatic densifying and buffering bin for straw raw material pulping provided in this embodiment, by integrally arranging at least one set of automatic densifying device inside the bin body, utilizes the periodic lifting and lowering movement of the pressure plate in the device under the action of the driving mechanism, and relies on its own weight to repeatedly compact the straw raw materials conveyed by the horizontal conveying device below when it descends, thereby effectively increasing the stacking density of the straw raw materials in the bin and the actual storage capacity per unit volume, significantly enhancing the buffering capacity of the bin to meet the requirements of the continuous and stable operation of the downstream production line, and further being able to reduce the physical volume, floor area and the corresponding equipment manufacturing cost and civil engineering investment of the buffering bin on the premise of ensuring the same buffering capacity.

[0039] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "vertical", "upper", "lower", "horizontal", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present application.

[0040] In the description of the present application, it should also be noted that, unless otherwise clearly defined and limited, the terms "arranged", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0041] Finally, it should be noted that the above are only the preferred embodiments of the present application and are not used to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An automatic density-increasing buffer silo for straw raw material pulping, characterized in that It includes a silo body, a feeding device, a discharging device, a densifying and pressurizing device, and a conveying device; the conveying device is arranged at the bottom of the silo body for horizontally conveying the straw raw materials in the silo body; the feeding device is arranged at the upper part of the silo body for introducing the straw raw materials into the upstream of the conveying device; the discharging device is arranged at the lower part of the silo body and downstream of the conveying device for discharging the densified straw raw materials from the silo body; the densifying and pressurizing device is arranged inside the silo body and above the conveying device. Among them, the densifying and pressurizing device includes a pressure plate and a driving mechanism installed on the top of the silo body of the silo. The driving mechanism is used to drive the pressure plate to lift periodically. During the descending process, the pressure plate compacts the straw raw materials conveyed by the conveying device directly below it by its own weight.

2. The automatic densification buffer bin for straw raw material pulping according to claim 1, characterized in that, The feeding device includes a cloth spiral. The cloth spiral is provided with a plurality of cloth outlets, and the plurality of cloth outlets are spaced along the conveying direction of the conveying device on the top of the silo body.

3. The automatic densification buffer bin for straw raw material pulping according to claim 2, characterized in that, There are four cloth outlets.

4. The automatic densification buffer bin for straw raw material pulping according to claim 3, characterized in that, A densifying and pressurizing device is provided between every two adjacent cloth outlets.

5. The automatic densification buffer bin for straw raw material pulping according to claim 1, characterized in that, The driving mechanism includes: A cylinder fixed on the top of the silo body; Two fixed sprockets rotatably fixed on the top of the silo body; A guide rail fixed on the top of the silo body and extending along the length direction of the cylinder; A moving sprocket pivotally connected to the end of the piston rod of the cylinder. The moving sprocket slides along the guide rail under the drive of the cylinder; A first chain, one end of which is fixed on the cylinder, and the other end is fixed on the pressure plate after successively bypassing the moving sprocket and the fixed sprocket.

6. The automatic densification buffer bin for straw raw material pulping according to claim 1, wherein The conveying device is a horizontal chain plate conveyor, and its running speed is adjustable from 0 to 1.5 m / min.

7. The automatic density-increasing buffer bin for straw raw material pulping according to claim 1, characterized in that, The discharging device includes a discharging port, a material deflecting device, and a discharging spiral. The discharging port is arranged at the end of the conveying direction of the conveying device and extends perpendicular to the conveying direction of the conveying device; the material deflecting device is used to deflect the straw raw materials in the silo body towards the discharging port, and the discharging spiral is horizontally arranged in the discharging port along the extending direction of the discharging port.

8. The automatic densification buffer bin for straw raw material pulping according to claim 7, wherein, The material deflecting device includes a driving motor and a plurality of material deflecting ratchets. The plurality of material deflecting ratchets are obliquely arranged upward at intervals in the silo body along the discharging port towards the feeding device; the driving motor synchronously drives the plurality of material deflecting ratchets to rotate through a set of second chains.

9. The automatic densification buffer bin for straw raw material pulping according to claim 7, characterized in that, The discharging port includes two oppositely arranged wall plates, and the two wall plates form a guiding port with a gradually expanding opening; among them, the wall plate close to the downstream of the conveying device is smoothly butted with the conveying device.

10. The automatic density-increasing buffer bin for straw raw material pulping according to claim 8, characterized in that, Three material deflecting ratchets are provided; among them, the orthographic projections of two adjacent material deflecting ratchets in the vertical direction at least partially overlap in the vertical direction.

Images