Biomass feeding system

Abstract

The utility model discloses a biomass feeding system. The biomass feeding system comprises a stock bin, at least one material uniformizing screw and at least one discharging screw. The material bin is provided with a feeding port and a discharging port, the material uniformizing spiral and the discharging spiral are both arranged in the material bin, the material uniformizing spiral is located below the feeding port, the discharging spiral is located below the material uniformizing spiral, the discharging end of the discharging spiral is located above the discharging port, and the discharging end of the discharging spiral is located above the discharging port. The material uniformizing spiral and the discharging spiral are arranged in a crossed mode. When the biomass feeding system is applied, the structure is simple, and the occupied installation space is small.

Description

Technical Field

[0001] The present application relates to the field of feeding technology, and in particular to a biomass feeding system. Background Art

[0002] Biomass is a renewable energy source with abundant sources. The annual production of fibrous biomass, such as branches, eucalyptus bark, and straw, reaches hundreds of millions of tons. Coupling this with coal-fired power generation not only fully utilizes biomass energy but also effectively reduces carbon emissions. Currently, biomass is typically crushed to a specific particle size using a feeding system before being fed into a boiler and co-fired with coal.

[0003] In the related art, in order to prevent blockage during the feeding process of biomass materials, biomass materials are often crushed into smaller particle sizes, such as less than 20 mm. However, biomass with smaller particle sizes is prone to generate a large amount of small dust particles during transportation, which poses risks such as dust overflow and explosion. To avoid this risk, the feeding system usually maintains a negative pressure state during the crushing process and the transportation process from the crusher to the silo, and the silo is kept closed at the same time. For example, the patent application with publication number CN113685806A discloses a biomass co-firing system based on a coal-fired boiler, which transports biomass with a particle size of less than 20 mm after crushing to a cyclone separator under the negative pressure generated by an induced draft fan. The large biomass particles separated by the cyclone separator are sent to a closed silo, and the small biomass particles are sent to a dust collector. The biomass intercepted by the dust collector is regularly discharged to the silo. The biomass in the silo is sent to the feed pipe of the pneumatic conveying system through the screw conveyor below, and is finally sent to the coal-fired boiler and coal-coated by the pneumatic conveying system. Although this solution can reduce the dust content in the closed silo and avoid the risk of dust overflow and explosion caused by the transportation of small-particle biomass, it requires the installation of an induced draft fan to provide a negative pressure environment for the feeding system. It also requires the installation of a cyclone separator and a dust collector, which makes the feeding process complicated and requires a large number of equipment types, resulting in a more complex system structure and taking up a larger installation space.

[0004] Therefore, how to provide a solution to overcome or alleviate the above-mentioned defects is still a technical problem that needs to be solved urgently by those skilled in the art. Utility Model Content

[0005] The purpose of this application is to provide a biomass feeding system with a relatively simple structure and taking up less installation space.

[0006] In order to solve the above technical problems, the present application provides a biomass feeding system, which includes a silo, at least one material leveling screw and at least one discharge screw;

[0007] The silo has a loading port and at least one unloading port, the material balancing spiral and the unloading spiral are both arranged inside the silo, the material balancing spiral is located below the loading port, the unloading spiral is located below the material balancing spiral, the discharge end of the unloading spiral is located above at least one of the unloading ports, and the material balancing spiral and the unloading spiral are arranged crosswise.

[0008] Optionally, the unloading screw includes a second rotating shaft and a second spiral blade, and the radius of the second spiral blade gradually increases along the conveying direction of the unloading screw.

[0009] Optionally, the maximum radius of the second spiral blade is defined as R1 and the minimum radius is defined as R2;

[0010] R1=(1.4~1.7)*R, and / or, R2=(1.1~1.3)*R;

[0011] Wherein, R is the radius of the second rotation axis.

[0012] Optionally, there are more than two material-distributing spirals, each of which includes a first rotating shaft, a first spiral blade, and a plurality of first stirring rods; the plurality of first stirring rods are provided on the first spiral blade, and the end surface of the first stirring rod exceeds the end surface of the first spiral blade at a corresponding position; and / or,

[0013] There are more than two unloading spirals, each of which includes a second rotating shaft, a second spiral blade, and a plurality of second stirring rods; the plurality of second stirring rods are provided on the second spiral blade, and the end surfaces of the second stirring rods extend beyond the end surfaces of the second spiral blades at corresponding positions; and / or,

[0014] The biomass feeding system further includes a baffle; the baffle is arranged on the inner side wall of the silo, and the baffle is located above the discharge end of the discharge screw.

[0015] Optionally, the distance from the end of the baffle to the horizontal plane where the axis of the unloading screw is located is defined as L, L=(1.8~2)*R; wherein R is the radius of the rotating shaft of the unloading screw.

[0016] Optionally, the biomass feeding system further comprises a pneumatic conveying system and at least one feeder;

[0017] The feeder and the discharge port are the same in number and correspond one to one. The feeder includes a feeding section and an impeller. The feeding section has a feed port, a rotary chamber, and a discharge port that are sequentially connected. The feed port is connected to the discharge port. The impeller is rotatably disposed in the rotary chamber. The discharge port is connected to the pneumatic conveying system.

[0018] The impeller includes a third rotating shaft and multiple feeding blades, and the rotating chamber corresponds to two rotating surfaces. The feeding blades and the rotating surfaces are defined as being in a contact state when the minimum gap between the end surface of the feeding blade and the rotating surface is maintained at a preset gap; during the rotation of the impeller, the two rotating surfaces are respectively in the contact state with at least one of the feeding blades.

[0019] Optionally, the size of the preset gap is 0.1 mm to 0.15 mm; and / or,

[0020] During the rotation of the impeller, at least one of the rotating surfaces and at least three circumferentially continuous feed blades are in the contact state; and / or,

[0021] The feed blades are made of elastic material; and / or,

[0022] The thickness of the feed blade gradually decreases from inside to outside along the radial direction of the third rotating shaft.

[0023] Optionally, the elastic material is spring steel; and / or,

[0024] The cross section of the feed blade perpendicular to the axis of the third rotating shaft is an isosceles trapezoid; and / or,

[0025] The thickness of the tip of the feeding blade is 2 mm to 2.5 mm.

[0026] Optionally, the feeder further includes a first scraper and a second scraper; the first scraper and the second scraper are arranged on the inner side wall of the feeding section and are both located on the side facing the rotation direction of the impeller, and the first scraper is located above the second scraper; the minimum distance between the end of the first scraper and the end of the feeding blade is defined as D1, and the minimum distance between the end of the second scraper and the end of the feeding blade is defined as D2, D1>D2; and / or,

[0027] The feeder further includes a transition section and a buffer section; the transition section, the buffer section and the feeding section are sequentially connected from top to bottom, the transition section is connected to the discharge port, and the buffer section has a shape that gradually expands from top to bottom.

[0028] Optionally, D1 is 40 mm to 50 mm; and / or,

[0029] D2 is 10mm~15mm; and / or,

[0030] The biomass feeding system further comprises a blowing system, a wall portion corresponding to the feed opening is provided with a purge channel, and the purge channel is connected to the blowing system; and / or,

[0031] The biomass feeding system further includes a blowing system, wherein a wall portion corresponding to the space between the first scraper and the second scraper is provided with a purge channel, the purge channel having a purge port, the purge port facing the rotary chamber, and the purge channel being in communication with the blowing system; and / or,

[0032] The biomass feeding system further includes a blowing system. The wall of the buffer section is provided with a purge channel, and the purge channel is communicated with the blowing system.

[0033] Optionally, the biomass feeding system further includes a data acquisition module and a central processing module;

[0034] The feeder further includes a third motor connected to the third rotating shaft, the data acquisition module is respectively connected to the third motor and the central processing module, and the central processing module is respectively connected to the third motor, the motor of the unloading screw, and the motor of the material leveling screw;

[0035] The data acquisition module is used to collect the operating frequency of the third motor and transmit the operating frequency data to the central processing module; the central processing module is used to control the third motor, the motor of the unloading screw, and the motor of the material leveling screw to reduce the operating frequency or stop when the operating frequency is lower than a preset frequency threshold.

[0036] The biomass feeding system provided in the present application is provided with at least one equalizing screw and at least one unloading screw in sequence from top to bottom below the upper feeding port inside the silo, and the discharge end of the unloading screw is located above the lower feeding port, and the equalizing screw and the unloading screw are cross-arranged. When in use, the equalizing screw can break up the biomass material entering the silo through the upper feeding port and evenly send it to the unloading screw below, and the unloading screw can further evenly send the biomass material to the lower feeding port. The two cooperate with each other to make the feeding of the silo more uniform and less prone to blockage. It can be used for feeding biomass materials with larger particle sizes, so that dust is less likely to be generated during the feeding process. The feeding process upstream of the silo and the silo itself do not need to be kept in a closed state. The feeding process is relatively simple and the types of feeding equipment required are relatively few, so that the structure of the feeding system is relatively simple and occupies a smaller installation space. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a process principle diagram of the biomass feeding system of the embodiment provided in this application;

[0038] Figure 2 This is a partial structural diagram of the biomass feeding system according to the embodiment of the present application;

[0039] Figure 3 for Figure 2 The structural diagram of the feeder shown;

[0040] Figure 4 for Figure 3 A partial enlarged view of the feeder at the feeding section is shown;

[0041] Figure 5 for Figure 3 The schematic diagram of the structure of the feeding blade in the feeder shown;

[0042] Figure 6 This is a control principle diagram of the biomass feeding system of the embodiment provided in this application.

[0043] The reference numerals in the above drawings are described as follows:

[0044] 1- silo, 1a- loading port, 1b- unloading port;

[0045] 2- material distribution screw, 21- first rotating shaft, 22- first spiral blade, 23- first motor;

[0046] 3-unloading screw, 31-second rotating shaft, 32-second spiral blade, 33-second motor;

[0047] 4- baffle;

[0048] 5-feeder, 51-transition section, 52-buffer section, 53-feeding section, 53a-feeding port, 53b-rotating chamber, 53c-discharging port, 53d-rotating surface, 53e-groove, 54-impeller, 541-third rotating shaft, 542-feeding blade, 55-third motor, 56-feeding section, 57-first scraper, 58-second scraper, 59-hand hole door;

[0049] 6-injection system, 61-injection pipeline;

[0050] 7-spray system, 71-spray pipeline, 72-spray head;

[0051] 8-dust removal system, 81-dust collector, 82-dust removal fan, 83-dust removal pipeline, 84-exhaust pipeline;

[0052] 9-Pneumatic conveying system, 91-Blower, 92-Material conveying pipeline. DETAILED DESCRIPTION

[0053] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0054] It should be noted that the "end" mentioned in this application is the end of the corresponding component that is not fixed. For example, the baffle 4 is fixed to the inner wall of the silo 1, and the end of the baffle 4 away from the inner wall of the silo 1 is the end; the first stirring rod and the first spiral blade are both fixed to the outer peripheral wall of the first rotating shaft 21, and the ends of the two are away from the first rotating shaft 21; the second stirring rod and the second spiral blade 32 are both fixed to the second rotating shaft 31, and the ends of the two are away from the second rotating shaft 31.

[0055] The terms "first", "second", etc. mentioned in this application are only used to facilitate the description of two or more structures or components with the same or similar structures and / or functions, and do not mean any special limitation on the order and / or importance.

[0056] In this application, unless otherwise specified or limited, the term "connection" should be understood in a broad sense. For example, it can mean a fixed connection, a detachable connection, or an integral connection; it can mean a mechanical connection or a communication connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean internal communication between two components. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0057] Please refer to Figures 1 to 2 , Figure 1 This is a process principle diagram of the biomass feeding system of the embodiment provided in this application. Figure 2 This is a partial structural diagram of the biomass feeding system of the embodiment provided in this application.

[0058] In the embodiment provided in the present application, the biomass feeding system includes a silo 1, at least one material leveling screw 2 and at least one unloading screw 3; the silo 1 has a loading port 1a and at least one unloading port 1b, the material leveling screw 2 and the unloading screw 3 are both arranged inside the silo 1, the material leveling screw 2 is located below the loading port 1a, the unloading screw 3 is located below the material leveling screw 2, and the discharge end of the unloading screw 3 is located above the at least one unloading port 1b, and the material leveling screw 2 and the unloading screw 3 are arranged crosswise.

[0059] In this way, the grading screw 2 can break up the biomass material entering the silo 1 through the feeding port 1a and evenly transport it to the unloading screw 3 below. The unloading screw 3 can further evenly transport the biomass material to the feeding port 1b. The grading screw 2 and the unloading screw 3 cooperate with each other to make the feeding of the silo 1 more uniform and less prone to blockage. It can be used for feeding biomass materials with larger particle sizes such as 50mm~80mm. Since biomass materials with larger particle sizes are less likely to generate dust during the feeding process, there is basically no risk of dust overflow and explosion, which makes the feeding process upstream of the silo 1 and the silo 1 more uniform. It does not need to be kept sealed, so there is no need to set up an induced draft fan to keep the upper crushing process and the transportation process from the upper crushing equipment to the silo in a negative pressure state as in the prior art. There is no need to set up a cyclone separator to reduce the dust content of the biomass material inside the silo, and there is no need to set up a dust collector to remove dust from the small particles of biomass material separated by the cyclone separator. The feeding process of biomass material can be simplified, and the types of feeding equipment required are fewer, so that the structure of the entire biomass feeding system is simpler, and it occupies a smaller installation space, which can also reduce the feeding cost of biomass material accordingly.

[0060] Moreover, compared with the related art in which the silo needs to be kept sealed and the material needs to be loaded into the silo through a pipe in a negative pressure state, which limits the loading capacity and makes it impossible to process large quantities of materials at one time, the biomass feeding system provided in the above embodiment of the present application does not need to be kept sealed, so the volume of the silo 1 can be set larger according to the amount of material, and the loading port 1a can be in an open state, so that a yard can be set up at the same time to pile up biomass materials, so that tools such as forklifts can be used to directly push the biomass materials in the yard into the silo 1, which not only increases the loading capacity of the silo 1, thereby increasing the feeding capacity of the biomass feeding system, but also makes the feeding operation more convenient and quick, which can improve the efficiency of biomass feeding.

[0061] In addition, compared with the related art, the feeding system can only transport biomass materials with smaller particle sizes, so that the biomass materials need to undergo multi-stage crushing. For example, the biomass materials collected in the material pit are first sent to the shredder for primary crushing by a conveying device, and then the biomass after primary crushing is sent to the hammer mill for secondary crushing by a screw conveyor. The biomass feeding system provided by the above embodiment of the present application can transport biomass materials with larger particle sizes, so that fewer crushing processes can be performed upstream of the silo 1. For example, only primary crushing is required, and there is no need for secondary crushing on site. The crushing process can be simplified and the number of crushing equipment and conveying equipment between crushing processes can be reduced accordingly, thereby further simplifying the structure of the biomass feeding system and reducing the installation space occupied by the system.

[0062] It is not difficult to understand that the material-leveling screw 2 and the discharge screw 3 can be screw conveyors without a shell. Specifically, the material-leveling screw 2 may include a first rotating shaft 21, a first spiral blade 22 and a first motor 23, the first spiral blade 22 is provided on the outer wall of the first rotating shaft 21, the first motor 23 is connected to the first rotating shaft 21, the first motor 23 is used to drive the first rotating shaft 21 to rotate, and the first rotating shaft 21 drives the first spiral blade 22 to rotate; the discharge screw 3 may include a second rotating shaft 31, a second spiral blade 32 and a second motor 33, the second spiral blade 32 is provided on the outer wall of the second rotating shaft 31, the second motor 33 is connected to the second rotating shaft 31, the second motor 33 is used to drive the second rotating shaft 31 to rotate, and the second rotating shaft 31 drives the second spiral blade 32 to rotate.

[0063] Among them, the first spiral blade 22 is spiral-shaped. As the first spiral blade 22 rotates, the biomass material entering the silo 1 through the loading port 1a is broken up and pushed forward along the axial direction of the first rotating shaft 21. During the pushing process, due to the action of gravity, the biomass material gradually falls onto the unloading spiral 3 below; the second spiral blade 32 is spiral-shaped. As the second spiral blade 32 rotates, the biomass material falling onto the unloading spiral 3 is pushed forward along the axial direction of the second rotating shaft 31, that is, pushed from the feeding end of the unloading spiral 3 to the discharging end, and finally falls into the corresponding unloading port 1b at the discharging end of the unloading spiral 3 due to the action of gravity for unloading.

[0064] In actual configuration, the specific positions and numbers of the loading port 1a and the unloading port 1b in the silo 1 are not limited.

[0065] like Figure 2 As shown, in the embodiment of the present application, there is one loading port 1a, which can be set on the upper side wall of the silo 1. The bottom of the silo 1 can be provided with at least two unloading ports 1b below the discharge end of each unloading screw 3. The two unloading ports 1b can be arranged in sequence along the axis of the unloading screw 3. In the conveying direction of the unloading screw 3, the unloading port 1b is relatively far away from the loading port 1a. In other words, the feeding end of the unloading screw 3 can be located below the loading port 1a, and the discharge end of the unloading screw 3 is relatively far away from the loading port 1a. Correspondingly, the material averaging screw 2 can be relatively far away from the discharge end of the unloading screw 3. In this way, the loading process of the silo 1 is not likely to affect the unloading process of the unloading screw 3, and the unloading efficiency of the unloading screw 3 is relatively high.

[0066] It is worth noting that when the feed port 1a is set on the side wall of the silo 1, the rotation direction of the material leveling screw 2 can be set so that the material is pushed from one side of the feed port 1a to the opposite side, that is, the side where the feed port 1a is located is the feeding end of the material leveling screw 2. In this way, the material leveling screw 2 can transport the material on one side of the feed port 1a to the side away from the feed port 1a, which can reduce the accumulation of biomass material on the side of the feed port 1a and make the silo 1 less likely to be blocked.

[0067] In actual setting, the material distribution screw 2 and the unloading screw 3 are arranged crosswise, that is, the projection of the axis of the first rotating shaft 21 and the axis of the second rotating shaft 31 on the horizontal plane has an angle, and the size of the angle is not limited. Figure 2 As shown, the angle can be 90 degrees, so that the feeding effect of the material balancing screw 2 and the discharge screw 3 is better and less likely to cause blockage.

[0068] In actual settings, the number of material balancing screws 2 and discharge screws 3 is not limited. For example, the material balancing screws 2 can be set to two, and the discharge screws 3 can be set to three. The two material balancing screws 2 can be set parallel to each other, and the three discharge screws 3 can be set parallel to each other. The two material balancing screws 2 can span the three discharge screws 3, and in the axial direction of the second rotating shaft 31, they can be respectively located at two trisection points of the discharge screw 3. In this way, the two material balancing screws 2 break up the material and send it to the three discharge screws 3, which can further improve the material balancing effect of the material balancing screw 2 and the discharge effect of the discharge screw 3, thereby making the feeding process of the silo 1 less prone to blockage, which is conducive to the stable and continuous operation of the biomass feeding system.

[0069] It is not difficult to understand that the biomass feeding system can also be equipped with a feeding device downstream of the silo 1, connecting the discharge port 1b of the silo 1 to the downstream feeding device. The biomass material transported by the discharge screw 3 falls into the discharge port 1b below due to gravity at the discharge end, and then falls into the downstream feeding device through the discharge port 1b, and is transported by the downstream feeding device to the terminal coal-fired boiler. The uniformity of the discharge amount of the silo 1 affects the operation of the downstream feeding device. For example, if the instantaneous feeding amount of the silo 1 is too large, it may lead to a large instantaneous discharge amount, which may cause the instantaneous feed amount of the downstream feeding device to be large, resulting in blockage of the downstream feeding device.

[0070] In the examples provided in this application, please refer to Figure 2 It is understood that the radius of the second spiral blade 32 in the unloading screw 3 gradually increases along the conveying direction of the unloading screw 3, that is, the radius of the part of the second spiral blade 32 close to the loading port 1a is smaller than the radius of the part far from the loading port 1a.

[0071] In this way, the second spiral blade 32 is tapered along the axial direction of the second rotating shaft 31, so that the biomass material conveying amount of the unloading spiral 3 from the feed end to the discharge end gradually increases, thereby realizing the controllable discharge amount of the silo 1. When the loading amount of the silo 1 is uneven, the discharge amount is still relatively uniform, so that the instantaneous feed amount of the downstream feeding equipment is not easy to be too large, and the downstream feeding equipment is not easy to get stuck, which is conducive to the stable and continuous operation of the biomass feeding system.

[0072] In actual configuration, the radius of the second spiral blade 32 is not limited.

[0073] Please combine Figure 2 It is understood that in the embodiment of the present application, the maximum radius of the second spiral blade 32 is defined as R1, and the minimum radius is defined as R2; R1 = (1.4~1.7)*R, R2 = (1.1~1.3)*R; where R is the radius of the second rotating shaft 31. The radius of the second spiral blade 32 at a certain position is the distance from the end face of the second spiral blade 32 at the corresponding position to the axis of the corresponding second rotating shaft 31. In this way, the maximum radius and minimum radius of the second spiral blade 32 are controlled within a reasonable range, so that the discharge amount of the unloading screw 3 is also controlled within a reasonable range, thereby making the discharge amount of the silo 1 more uniform and making the downstream feeding equipment less likely to get stuck.

[0074] In addition, the second motor 33 of the unloading screw 3 can also be set as a variable frequency motor, so that the operating frequency of the second motor 33 can be adjusted according to the loading amount of the silo 1, thereby further controlling the unloading amount of the silo 1, making the instantaneous feeding amount of the downstream feeding equipment more uniform, so that the downstream feeding equipment is less likely to get stuck, which is conducive to the stable and continuous operation of the biomass feeding system.

[0075] In the embodiment provided herein, the material-leveling screw 2 further includes a plurality of first stirring rods (not shown in the figure). The first stirring rods may be provided on the first rotating shaft 21, with the distal end surfaces of the first stirring rods extending beyond the distal end surfaces of the first spiral blades 22 at corresponding positions. During use, the rotation of the first rotating shaft 21 drives the first stirring rods to rotate, stirring the material around the material-leveling screw 2. This not only enhances the material-leveling effect of the material-leveling screw 2, but also prevents biomass material from bridging between adjacent material-leveling screws 2, making the silo 1 less susceptible to blockage.

[0076] In the embodiment provided herein, the discharge screw 3 further includes a plurality of second stirring rods, which may be mounted on the second rotating shaft 31. The distal end surfaces of the second stirring rods extend beyond the distal end surfaces of the corresponding second spiral blades 32. During operation, rotation of the second rotating shaft 31 drives the secondary stirring rods, which in turn stir the material circumferentially of the discharge screw 3. This not only enhances the uniformity of material conveyance by the discharge screw 3 but also prevents biomass material from bridging between adjacent discharge screws 3, making the silo 1 less susceptible to blockage.

[0077] During the specific setting, the position of the first stirring rod on the first rotating shaft 21 is not limited. For example, one end of the first stirring rod can be fixed to the outer wall of the first rotating shaft 21, and the outer wall of the first stirring rod can be fixed to the side wall of the first spiral blade 22. The length of the first stirring rod is greater than the distance from the end face of the first spiral blade 22 at the corresponding position to the outer wall of the first rotating shaft 21, so that the other end of the first stirring rod, that is, the end face of the end, exceeds the end face of the first spiral blade 22 at the corresponding position. In this way, the stirring effect of the first stirring rod is better, and it is less likely to bridge between adjacent material balancing spirals 2, and the silo 1 is less likely to be blocked.

[0078] In specific configuration, the position where the second stirring rod is disposed on the second rotating shaft 31 is similar to the position where the first stirring rod is disposed on the first rotating shaft 21 , and details thereof will not be repeated herein.

[0079] During the specific setting, the number and arrangement of the first stirring rod and the second stirring rod are not limited. Taking the first stirring rod as an example, multiple first stirring rods can be set. Specifically, one first stirring rod can be set in the part corresponding to each pitch of the first spiral blade 22, or more than two first stirring rods can be set in the part corresponding to each pitch of the first spiral blade 22. The multiple first stirring rods can be evenly spaced along the circumference of the first rotating shaft 21.

[0080] like Figure 2 As shown, in the embodiment provided herein, the biomass feeding system further includes a baffle 4, which is disposed on the inner sidewall of the silo 1 and is located above the discharge end of the discharge screw 3. When in use, the baffle 4 prevents biomass material entering the silo 1 through the feed port 1a from falling into the side of the discharge port 1b, making the discharge port 1b less susceptible to clogging and facilitating stable and continuous operation of the biomass feeding system.

[0081] It is easy to understand that the baffle 4 can be tilted, with one end fixed to the inner wall of the silo 1 and the other end, i.e., the distal end, extending above the discharge end of the discharge screw 3, specifically, above the discharge opening 1b closest to the loading opening 1a. The distance from the distal end of the baffle 4 to the horizontal plane of the axis of the discharge screw 3 is defined as L. In actual configuration, the distance L is not limited.

[0082] In the embodiment of the present application, L = (1.8-2) * R, where R is the radius of the rotating shaft of the discharge screw 3. By limiting the vertical distance from the end of the baffle 4 to the axis of the discharge screw 3 to an appropriate range, the baffle 4 can enhance its ability to block the biomass material from above and prevent the baffle 4 from interfering with the discharge process of the discharge screw 3.

[0083] Please refer to Figures 3 and 4 , Figure 3 for Figure 2 The structural diagram of the feeder is shown in FIG. Figure 4 for Figure 3 A partial enlarged view of the feeder at the feeding section is shown.

[0084] In the examples provided in this application, Figures 1 to 4 As shown, the biomass feeding system also includes a pneumatic conveying system 9 and at least one feeder 5; the number of feeders 5 and the discharge port 1b are the same and correspond one to one, the feeder 5 includes a feeding section 53 and an impeller 54, the feeding section 53 has a feed port 53a, a rotary chamber 53b and a discharge port 53c connected in sequence; the feed port 53a is connected to the discharge port 1b, the impeller 54 is rotatably arranged in the rotary chamber 53b, and the discharge port 53c is connected to the pneumatic conveying system 9; the impeller 54 includes a third rotating shaft 541 and a plurality of feeding blades 542, and the rotary chamber 53b corresponds to two rotating surfaces 53d, and the feeding blade 542 and the rotating surface 53d are defined as being in a contact state when the minimum gap between the end face of the feeding blade 542 and the rotating surface 53d is maintained at a preset gap; during the rotation of the impeller 54, the two rotating surfaces 53d are respectively in contact with at least one feeding blade 542.

[0085] It is understood that the feeder 5 may further include a third motor 55, a plurality of feed blades 542 may be circumferentially spaced apart along the outer wall of the third rotating shaft 541, the feed blades 542 may extend radially along the third rotating shaft 541, and the third motor 55 may be connected to the third rotating shaft 541 to control the third rotating shaft 541 to drive the feed blades 542 to rotate; Figure 4 From the perspective, the rotating chamber 53b corresponds to four side walls, namely two cylindrical surfaces on the left and right sides, namely the rotating surface 53d, and two inner wall surfaces on the front and back sides; the pneumatic conveying system 9 may include a blower 91 and several material conveying pipes 92 connected to each other, and the material conveying pipes 92 are connected to the discharge port 53c of at least one feeder 5.

[0086] Among them, when the end of the feeding blade 542 is located in the rotating chamber 53b, the feeding blade 542 and the rotating surface 53d are in a contact state, and the preset gap corresponding to the contact state is greater than or equal to 0; a storage chamber can be formed between the side wall surface of two circumferentially adjacent feeding blades 542 in the impeller 54 and the side wall surface of the third rotating shaft 541 for temporarily storing biomass materials. As the impeller 54 rotates, the tips of some feeding blades 542 leave the rotary chamber 53b and enter the upper feed port 53a, and the corresponding storage chambers are open toward the feed port 53a. After the biomass material in the silo 1 is fed into the discharge port 1b by the unloading screw 3, it will fall into the storage chambers open on both sides of the feeding blades 542 through the feed port 53a. Then, the tips of the feeding blades 542 corresponding to these storage chambers first enter the rotary chamber 53b and are in contact with the rotating surface 53d, and finally leave the rotary chamber 53b and enter the discharge port 53c. The corresponding storage chambers are open toward the discharge port 53c, and the internal biomass material falls into the discharge port 53c and enters the feed pipe 92 of the pneumatic conveying system 9 through the discharge port 53c, and is sent to the downstream coal-fired boiler and coal-fired coupled power generation under the action of the blower 91.

[0087] In this way, compared with the related art in which the biomass material is only fed into the feeding pipe of the pneumatic conveying system by a screw conveyor using the principle of spiral blade rotation and extrusion, the high-pressure gas in the pneumatic conveying system is easily returned into the silo. In particular, when there is less biomass material in the silo and it cannot be squeezed to fill the shell space of the screw conveyor, there is an obvious gas return problem. The biomass feeding system provided in the above embodiment of the present application forms an impeller-type feeder 5 due to the rotation of the impeller 54 in the feeding section 53, and when the impeller 54 rotates to feed During the feeding process, the two rotating surfaces 53d of the feeding section 53 are in contact with at least one feeding blade 542 respectively. These feeding blades 542 can relatively ensure the airtightness of the feeder 5 and relatively isolate the pneumatic conveying system 9 and the silo 1, so that the amount of material inside the silo 1 has no effect on the operation of the pneumatic conveying system 9. Even if the amount of material inside the silo 1 is small, the high-pressure gas inside the feeding pipe 92 of the pneumatic conveying system 9 is not easy to be reversed to the inside of the silo 1 through the feeder 5, which is conducive to the stable and continuous operation of the biomass feeding system.

[0088] In actual settings, the size of the above preset gap is not limited.

[0089] In the embodiment of the present application, the preset gap is 0.1 mm to 0.15 mm. By maintaining the preset gap within an appropriate range, the feeder blade 542 and the rotating surface 53d maintain a slight clearance fit. This not only ensures the airtightness of the feeder 5, preventing the high-pressure gas inside the pneumatic conveying system 9 from flowing back into the silo 1, but also allows the feeder blade 542 to rotate freely within the rotating chamber 53b, thereby relatively ensuring the feeding efficiency of the feeder 5.

[0090] In actual configuration, during the rotation of the impeller 54 , the number of the feed blades 542 that maintain contact with each rotating surface 53 d is not limited.

[0091] In the embodiments of this application, Figure 4 As shown, during the rotation of the impeller 54, at least one rotating surface 53d is in contact with at least three circumferentially continuous feed blades 542. This further ensures the airtightness of the feeder 5, making it more difficult for the high-pressure gas inside the pneumatic conveying system 9 to flow back into the silo 1.

[0092] The specific number of the feeding blades 542 is not limited. For example, the number of the feeding blades 542 can be set as follows: Figure 4 Among the multiple ones shown, one rotating surface 53d is always in contact with three circumferentially continuous feed blades 542, and the other rotating surface 53d is always in contact with one feed blade 542 or more circumferentially continuous feed blades 542.

[0093] In actual configuration, the material of the feeding blade 542 is not limited.

[0094] In the embodiment provided in this application, the feed blade 542 is made of elastic material.

[0095] It is not difficult to understand that when the end of the feeding blade 542 is drawn into a small amount of biomass material and enters the rotating chamber 53b, the shell corresponding to the feeding section 53 applies an extrusion force to the feeding blade 542 through the biomass material, causing the feeding blade 542 to elastically deform and be compressed along the radial direction of the third rotating shaft 541 toward the side away from the rotating surface 53d. As a result, the feeder 5 is not easily blocked due to the end of the feeding blade 542 being drawn into the biomass material, and is more suitable for feeding large-particle biomass materials. At the same time, since the biomass material occupies the gap between the end of the feeding blade 542 and the rotating surface 53d, the airtightness of the feeder 5 can be further guaranteed, making it more difficult for the high-pressure gas inside the pneumatic conveying system 9 to flow back to the silo 1. In addition, when the feeding blade 542 rotates out of the rotary chamber 53b and enters the discharge port 53c, the biomass material caught by the end of the feeding blade 542 falls off and enters the discharge port 53c, the above-mentioned extrusion force disappears, the elastic deformation of the feeding blade 542 is restored, and it can continue to rotate to perform subsequent feeding work, so that the entire biomass feeding system can operate stably and continuously.

[0096] In the specific configuration, the type of the elastic material is not limited. For example, the elastic material can be spring steel, so that the feed blade 542 has not only good elasticity but also high strength, and the edge at the end can be used to shear the biomass material involved, making the feeder 5 less likely to get stuck.

[0097] Please refer to Figure 5, Figure 5 for Figure 3 Schematic diagram of the structure of the feeding blades in the feeder shown.

[0098] In actual configuration, the shape and size of the feed blades 542 are not limited.

[0099] like Figure 5 As shown, the thickness of the feed blade 542 gradually decreases from the inside to the outside along the radial direction of the third rotating shaft 541. In other words, the end of the feed blade 542 closer to the third rotating shaft 541 is thicker, and the end farther from the third rotating shaft 541, i.e., the tip, is thinner. This creates a sharper shearing edge at the tip of the feed blade 542, which enhances the shearing effect on the entrained biomass material, making the feeder 5 less prone to clogging and making it more suitable for feeding large-particle biomass material.

[0100] In the embodiment of the present application, the cross section of the feeding blade 542 perpendicular to the axis of the third rotating shaft 541 is an isosceles trapezoid, which can further enhance the cutting effect of the end of the feeding blade 542 on the biomass material.

[0101] In the embodiment of the present application, the thickness of the end of the feed blade 542 is d, and d is between 2 mm and 2.5 mm. In this way, the thickness of the end of the feed blade 542 is kept within an appropriate range, which can ensure the toughness of the feed blade 542 while ensuring the shearing effect of the feed blade 542 on the biomass material.

[0102] Please combine Figure 3 and Figure 4 It is understood that in the embodiment provided in the present application, the feeder 5 also includes a first scraper 57, which is arranged on the inner wall of the feeding section 53 and is located on the side facing the rotation direction of the impeller 54. The minimum distance between the end of the first scraper 57 and the end of the feeding blade 542 is defined as D1, and D1>0.

[0103] In this way, the first scraper 57 is located in the space before the feeding blade 542 rotates and contacts the rotating surface 53d. The first scraper 57 can first play a material guiding role, and can guide the biomass material inside the feed port 53a into the open storage chamber, so that the biomass material is not easily rolled into the end of the feeding blade 542; when part of the biomass material is wrapped around the end of the feeding blade 542, the first scraper 57 can also play a scraping role. Specifically, when the feeding blade 542 rotates past the vicinity of the first scraper 57, the first scraper 57 can scrape this part of the biomass material away from the feeding blade 542, making it away from the initial contact position of the feeding blade 542 and the rotating surface 53d, making the feeder 5 less likely to be blocked and more suitable for feeding large-particle-size biomass materials.

[0104] In the embodiment provided in the present application, the feeder 5 also includes a second scraper 58; the second scraper 58 is arranged on the inner wall of the feeding section 53 and is located on the side facing the rotation direction of the impeller 54, and the second scraper 58 is located below the first scraper 57; the minimum distance between the end of the second scraper 58 and the end of the feeding blade 542 is defined as D2, D1>D2.

[0105] Thus, the first scraper 57 and the second scraper 58 are designed in a front-to-back stepped manner along the rotation direction of the feed blade 542, and are located in the space before the feed blade 542 rotates and contacts the rotating surface 53d. After the first scraper 57 performs an initial scraping operation on the feed blade 542, when the feed blade 542 rotates to the vicinity of the second scraper 58, the second scraper 58 can further scrape the biomass material remaining after the first scraper 57 scrapes the end of the feed blade 542 away from the feed blade 542. The coordinated action of the first scraper 57 and the second scraper 58 achieves both material guidance and dual scraping of the biomass material, making it less likely for biomass material to enter the gap between the end of the feed blade 542 and the rotating surface 53d. This makes the feeder 5 less susceptible to clogging and more suitable for feeding large-particle biomass material.

[0106] During specific settings, the sizes of the above distance parameters D1 and D2 are not limited.

[0107] In the embodiment of the present application, D1 is 40 mm to 50 mm, and D2 is 10 mm to 15 mm. This allows the distances between the ends of the first scraper 57, the second scraper 58, and the feeding blade 542 to be maintained within appropriate ranges. This ensures the material guiding effect of the first scraper 57, the scraping effect of the first scraper 57 and the second scraper 58, and the feeding efficiency of the feeder 5, thereby facilitating the stable and continuous operation of the biomass feeding system.

[0108] In the specific setting, the first scraper 57 and the second scraper 58 can be arranged at the connection between the wall portion corresponding to the rotary cavity 53b in the feeding section 53 and the wall portion corresponding to the feed port 53a. For example, one end of the first scraper 57 and the second scraper 58 can be fixed to the inner wall surface corresponding to the feed port 53a, and the inner wall corresponding to the rotary cavity 53b can be opened at one end near the feed port 53a. Figure 4 The groove 53 e shown provides an escape space for the first scraper 57 and the second scraper 58 to scrape the biomass material wrapped around the end of the feeding blade 542 .

[0109] Please combine Figure 2 and Figure 3 It is understood that in the embodiment provided in the present application, the feeder 5 also includes a transition section 51 and a buffer section 52; the transition section 51, the buffer section 52 and the feeding section 53 are connected in sequence from top to bottom, the transition section 51 is connected to the discharge port 1b, and the buffer section 52 has a shape that gradually expands from top to bottom.

[0110] During use, the biomass material discharged from the silo 1 into the discharge port 1b through the discharge screw 3 first falls into the transition section 51 of the feeder 5, and then enters the buffer section 52. The buffer section 52 forms a buffer silo with a downward flaring, that is, the end of the buffer section 52 close to the transition section 51 is a small opening, and the end close to the feeding section 53 is a large opening, which can make it difficult for the biomass material to form a stable arch structure in the buffer silo, that is, it is not easy to form a bridge, thereby further ensuring that the feeder 5 is not easily blocked, making it more suitable for feeding large-particle-size biomass materials, and is also conducive to the stable and continuous operation of the biomass feeding system.

[0111] In the embodiments of this application, Figure 2 and Figure 3 As shown, the feeder 5 may further include a feeding section 56, the feeding end of the feeding section 56 is connected to one end of the discharge port 53c of the feeding section 53, and the discharge end of the feeding section 56 can be connected to the feeding pipe 92 of the pneumatic conveying system 9, which is used to feed the biomass material delivered by the impeller 54 of the feeding section 53 into the pneumatic conveying system 9, which can improve the feeding efficiency of the feeder 5 and at the same time make the feeder 5 less likely to be blocked.

[0112] In the embodiments of this application, Figure 3 As shown, the buffer section 52 in the feeder 5 can be provided with a hand hole door 59. When the buffer section 52 is blocked, the hand hole door 59 can be quickly opened to clear the material inside the feeder 5 and to perform maintenance on the inside.

[0113] Please combine Figure 1 It is understood that in the embodiment provided herein, the biomass feeding system further includes a blowing system 6. A purge channel may be provided on the wall corresponding to the discharge port 1b, and the purge channel is connected to the blowing system 6. A purge channel may also be provided on the wall corresponding to the space between the first scraper 57 and the second scraper 58. The purge channel has a purge port that faces the rotary chamber 53b, and the purge channel is connected to the blowing system 6. A purge channel may also be provided on the wall of the buffer section 52, and the purge channel is connected to the blowing system 6. The blowing system 6 has a plurality of blowing pipelines 61, and the purge channels are specifically connected to the blowing pipelines 61.

[0114] In this way, the blowing system 6 can be used to intermittently blow compressed air to the space of the discharge port 1b, the space between the first scraper 57 and the second scraper 58, and the space inside the buffer section 52, and use compressed air to purge the biomass materials in these spaces, so that the biomass materials are not likely to bridge in these local spaces, and are not likely to accumulate locally, thereby making the biomass feeding system provided in the embodiment of the present application more suitable for feeding biomass materials with larger particle sizes and operating more stably.

[0115] Please refer to Figure 6 , Figure 6 This is a control principle diagram of the biomass feeding system of the embodiment provided in this application.

[0116] In the embodiment provided in the present application, the biomass feeding system also includes a data acquisition module (not shown in the figure) and a central processing module (not shown in the figure); the data acquisition module is respectively connected to the third motor 55 and the central processing module, and the central processing module is respectively connected to the third motor 55 of the feeder 5, the second motor 33 of the unloading screw 3, and the first motor 23 of the material leveling screw 2; the data acquisition module is used to collect the operating frequency of the third motor 55 and transmit the operating frequency data to the central processing module; the central processing module is used to control the third motor 55, the second motor 33, and the first motor 23 to stop when the operating frequency is lower than the preset frequency threshold X.

[0117] In this way, through the above-mentioned interlocking protection, when the feeder 5 is blocked due to the influence of foreign matter and the operating frequency is reduced, the feeder 5, the discharge screw 3 and the equalizing screw 2 are controlled to stop to prevent these feeding equipment from being further damaged.

[0118] Of course, when the operating frequency of the third motor 55 is lower than the frequency threshold X, the three motors may not be controlled to stop, but the operating frequencies of the three motors may be controlled to reduce to alleviate the jamming situation, which is not specifically limited.

[0119] like Figure 1 As shown, in the embodiment provided in this application, the biomass feeding system further includes a spray system 7; the spray system 7 comprises interconnected spray pipes 71 and a plurality of nozzles 72, which are arranged on the inner wall of the silo 1 and above the material leveling screw 2. In this way, when a small amount of dust may be generated during the unloading process inside the silo 1, especially on the side of the loading port 1a, the spray system 7 can be activated to spray water mist into the interior of the silo 1, thereby reducing the risk of dust explosion in the silo 1 and facilitating the stable and continuous operation of the biomass feeding system.

[0120] like Figure 1 As shown, in the embodiment provided in the present application, the biomass feeding system further includes a dust removal system 8; the dust removal system 8 includes a dust collector 81 and a dust removal fan 82, the ash inlet of the dust collector 81 is connected to the loading port 1a of the silo 1 through a dust removal pipeline 83, the air outlet of the dust collector 81 is connected to the air inlet of the dust removal fan 82, and the exhaust port of the dust removal fan 82 is connected to the outside world through an exhaust pipeline 84. In this way, when a small amount of dust may appear during the unloading process inside the silo 1, especially on the side of the loading port 1a, the dust removal system 8 can be started to absorb and discharge this small amount of dust from the silo 1, making the silo 1 less likely to cause dust explosion accidents, which is conducive to the stable and continuous operation of the biomass feeding system.

[0121] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only intended to help understand the device and its core concept of this application. It should be noted that for those skilled in the art, without departing from the principles of this application, various improvements and modifications can be made to this application, and such improvements and modifications also fall within the scope of protection of the claims of this application.

Claims

1. A biomass feeding system, characterized in that: The biomass feeding system comprises a silo (1), at least one material leveling screw (2) and at least one discharge screw (3); The silo (1) has a loading port (1a) and at least one unloading port (1b), the material-leveling spiral (2) and the unloading spiral (3) are both arranged inside the silo (1), the material-leveling spiral (2) is located below the loading port (1a), the unloading spiral (3) is located below the material-leveling spiral (2), the discharge end of the unloading spiral (3) is located above at least one of the unloading ports (1b), and the material-leveling spiral (2) and the unloading spiral (3) are arranged crosswise.

2. The biomass feeding system according to claim 1, characterized in that: The unloading screw (3) comprises a second rotating shaft (31) and a second spiral blade (32), and the radius of the second spiral blade (32) gradually increases along the conveying direction of the unloading screw (3).

3. The biomass feeding system according to claim 2, characterized in that: The maximum radius of the second spiral blade (32) is defined as R1, and the minimum radius is defined as R2; R1=(1.4~1.7)*R, and / or, R2=(1.1~1.3)*R; Wherein, R is the radius of the second rotating shaft (31).

4. The biomass feeding system according to any one of claims 1 to 3, characterized in that: There are more than two material-leveling spirals (2), and the material-leveling spirals (2) include a first rotating shaft (21), a first spiral blade (22), and a plurality of first stirring rods; the plurality of first stirring rods are arranged on the first spiral blade (22), and the end faces of the first stirring rods extend beyond the end faces of the first spiral blade (22) at corresponding positions; and / or, There are more than two unloading screws (3), and the unloading screw (3) includes a second rotating shaft (31), a second spiral blade (32) and a plurality of second stirring rods; the plurality of second stirring rods are arranged on the second spiral blade (32), and the end surface of the second stirring rod exceeds the end surface of the second spiral blade (32) at the corresponding position; and / or, The biomass feeding system further comprises a baffle (4); the baffle (4) is arranged on the inner side wall of the silo (1), and the baffle (4) is located above the discharge end of the discharge screw (3).

5. The biomass feeding system according to claim 4, characterized in that: The distance from the end of the baffle (4) to the horizontal plane where the axis of the unloading screw (3) is located is defined as L, L=(1.8~2)*R; wherein R is the radius of the rotating shaft of the unloading screw (3).

6. The biomass feeding system according to any one of claims 1 to 3, characterized in that: The biomass feeding system further comprises a pneumatic conveying system (9) and at least one feeder (5); The feeder (5) and the discharge port (1b) are the same in number and correspond one to one. The feeder (5) includes a feeding section (53) and an impeller (54). The feeding section (53) has a feed port (53a), a rotary chamber (53b) and a discharge port (53c) that are connected in sequence. The feed port (53a) is connected to the discharge port (1b). The impeller (54) is rotatably arranged in the rotary chamber (53b). The discharge port (53c) is connected to the pneumatic conveying system (9). The impeller (54) includes a third rotating shaft (541) and a plurality of feeding blades (542); the rotating chamber (53b) corresponds to two rotating surfaces (53d); the feeding blades (542) and the rotating surfaces (53d) are defined as being in a contact state when the minimum gap between the end surface of the feeding blade (542) and the rotating surface (53d) is maintained at a preset gap; during the rotation of the impeller (54), the two rotating surfaces (53d) are respectively in the contact state with at least one of the feeding blades (542).

7. The biomass feeding system according to claim 6, characterized in that: The size of the preset gap is 0.1mm~0.15mm; and / or, During the rotation of the impeller (54), at least one of the rotating surfaces (53d) and at least three circumferentially continuous feed blades (542) are in the contact state; and / or, The feed blade (542) is made of elastic material; and / or, The thickness of the feeding blade (542) gradually decreases from the inside to the outside along the radial direction of the third rotating shaft (541).

8. The biomass feeding system according to claim 7, characterized in that: The elastic material is spring steel; and / or The cross section of the feeding blade (542) perpendicular to the axis of the third rotating shaft (541) is an isosceles trapezoid; and / or, The thickness of the tip of the feeding blade (542) is 2 mm to 2.5 mm.

9. The biomass feeding system according to claim 6, characterized in that: The feeder (5) further comprises a first scraper (57) and a second scraper (58); the first scraper (57) and the second scraper (58) are arranged on the inner side wall of the feeding section (53) and are both located on the side facing the rotation direction of the impeller (54), and the first scraper (57) is located above the second scraper (58); the minimum distance between the end of the first scraper (57) and the end of the feeding blade (542) is defined as D1, and the minimum distance between the end of the second scraper (58) and the end of the feeding blade (542) is defined as D2, D1>D2; and / or, The feeder (5) further comprises a transition section (51) and a buffer section (52); the transition section (51), the buffer section (52) and the feeding section (53) are sequentially connected from top to bottom, the transition section (51) is communicated with the discharge port (1b), and the buffer section (52) has a shape that gradually expands from top to bottom.

10. The biomass feeding system according to claim 9, characterized in that: D1 is 40mm~50mm; and / or, D2 is 10mm~15mm; and / or, The biomass feeding system further comprises a blowing system (6), a wall portion corresponding to the feed opening (1b) is provided with a purge channel, and the purge channel is in communication with the blowing system (6); and / or, The biomass feeding system further comprises a blowing system (6), a wall portion corresponding to the space between the first scraper (57) and the second scraper (58) is provided with a purge channel, the purge channel having a purge port, the purge port facing the rotary chamber (53b), the purge channel being in communication with the blowing system (6); and / or, The biomass feeding system further comprises a blowing system (6), and a purge channel is provided on the wall of the buffer section (52), and the purge channel is in communication with the blowing system (6).

11. The biomass feeding system according to claim 6, characterized in that: The biomass feeding system also includes a data acquisition module and a central processing module; The feeder (5) further comprises a third motor (55), the third motor (55) being connected to the third rotating shaft (541), the data acquisition module being connected to the third motor (55) and the central processing module respectively, and the central processing module being connected to the third motor (55), the motor of the unloading screw (3), and the motor of the material leveling screw (2) respectively; The data acquisition module is used to collect the operating frequency of the third motor (55) and transmit the operating frequency data to the central processing module; the central processing module is used to control the third motor (55), the motor of the unloading screw (3), and the motor of the material leveling screw (2) to reduce the operating frequency or stop when the operating frequency is lower than a preset frequency threshold.

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