Biomass fuel preparation system suitable for raw materials with different water contents and working method of biomass fuel preparation system

Abstract

The invention discloses a biomass fuel preparation system suitable for raw materials with different water contents and a working method of the biomass fuel preparation system, and belongs to the technical field of biomass fuel processing. The preparation system comprises a biomass feeder, a feeding electric push rod, a base, a hydraulic machine, a material tray and a material taking electric push rod, a cavity in the biomass feeder can store biomass crushed materials, the feeding electric push rod can push the biomass feeder to do reciprocating motion along the plane of the base, and the base is used for bearing and keeping the working face horizontal. A hydraulic head is arranged on the hydraulic machine and can do reciprocating motion in the vertical direction, the crushed biomass materials are compressed into biomass profiling blocks, the crushed biomass materials can be placed on the material tray, and the material taking electric push rod can push the material tray to do reciprocating motion in the vertical direction. The method provided by the invention can adapt to biomass crushed materials with different moisture contents, each component has no easily-lost part, the continuous production requirement is met, the production efficiency is improved, the shape and size of the formed block are variable, and the production flexibility is high.

Description

Technical Field

[0001] This invention relates to the field of biomass fuel processing technology, and in particular to a biomass fuel preparation system and its working method that are adaptable to raw materials with different moisture contents. Background Technology

[0002] Biomass solid briquettes are a type of clean fuel made from agricultural and forestry waste such as straw and sawdust, as well as agricultural processing residues, through processes including crushing, drying, and high-pressure molding. They typically take the form of regular granules or blocks with a significantly increased density, facilitating storage and transportation. This fuel is characterized by high calorific value, low ash content, and low sulfur content, exhibiting high combustion efficiency and low pollutant emissions, making it an economical and environmentally friendly fuel option. In the context of continuously growing global energy demand and increasing environmental awareness, vigorously developing biomass briquettes can not only effectively reduce environmental pollution problems such as open burning of straw, but also help replace traditional fossil fuels such as loose coal, optimize the energy consumption structure, reduce dependence on fossil fuels, and is of great significance for building a clean and low-carbon energy system.

[0003] Currently, the processing technology for biomass solid briquettes faces several major challenges in practical applications. First, existing technologies have extremely stringent requirements regarding the moisture content of raw materials. For example, mainstream processes like ring die extrusion typically require precise control of the raw material's moisture content within the range of 8% to 20% for effective molding. Too low a moisture content leads to poor inter-particle bonding, making molding difficult; too high a moisture content makes extrusion under high pressure easy, resulting in loose particles or clogged die holes. This necessitates time-consuming and energy-intensive precise drying or humidification of the raw materials before production, increasing the complexity and energy consumption of the process. Second, existing equipment generally relies heavily on specific molds, and mold wear and clogging are persistent problems in the industry. Under high pressure and high-speed friction, the die holes of ring or flat dies are prone to rapid wear or clogging due to material friction and corrosion, with wear accounting for over 65% of failure modes. This necessitates frequent machine shutdowns for cleaning or mold replacement, significantly increasing maintenance costs and worker workload, and severely disrupting production continuity, making large-scale, long-term stable operation difficult. Finally, traditional molding machines typically use a single mold to produce products of fixed shapes and sizes, lacking flexibility. When market demand changes necessitates adjustments to product specifications, production must be halted, requiring significant time and manpower to replace molds. This time-consuming and labor-intensive process hinders the flexible response to market demands for diverse fuel blocks (such as different shapes and sizes), limiting its application scope and economic viability. These shortcomings collectively constrain the improvement of biomass fuel production efficiency and economic benefits. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a biomass fuel preparation system and its operating method that are adaptable to raw materials with different moisture contents, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A biomass fuel preparation system adaptable to raw materials with different moisture contents includes: a pneumatic conveying pipeline, a biomass feeder, a feeding electric push rod, a base, a hydraulic press, a material tray, a material removal electric push rod, a biomass briquetting conveyor belt, and a biomass briquetting cutter. The pneumatic conveying pipeline transports compressed biomass pulverized material into the biomass feeder, which has an internal cavity for storing the pulverized material. The feeding electric push rod pushes the biomass feeder in a reciprocating motion along the base plane. The base serves to bear weight and maintain a level working surface, preventing vibration. The hydraulic press has a hydraulic head that reciprocates vertically, compressing the pulverized biomass material into biomass briquettes. The material tray is located below the hydraulic press and can hold the pulverized biomass material. The material removal electric push rod is located below the material tray and pushes it vertically in a reciprocating motion. The biomass briquetting conveyor belt transports the produced biomass briquettes to the biomass briquetting cutter.

[0006] A further improvement of the system of the present invention is that, The pneumatic conveying pipeline has two lines connected to the cavity of the biomass feeder, namely the air inlet line and the air outlet line. The pneumatic conveying pipeline carries the crushed biomass material from the air inlet line into the cavity of the biomass feeder through the compressed air, and the compressed air is then discharged from the cavity through the air outlet line. Due to the high resistance of the pipeline at this point, the denser crushed biomass material is retained here.

[0007] A further improvement to the system of the present invention is that it further includes: The biomass briquette conveyor belt transports the produced biomass briquettes from the base to the biomass briquette cutter. The biomass briquette cutter is highly flexible in production and can cut biomass briquettes into the required shapes and sizes.

[0008] A further improvement to the system of the present invention is that it further includes: The pneumatic conveying pipeline has two air inlet pipes and two air outlet pipes. The air outlet pipe is equipped with a screen with a 2-16mm aperture to prevent large biomass crushed material from flowing back.

[0009] A further improvement to the system of the present invention is that it further includes: The hydraulic press can output a specified hydraulic pressure or hydraulic stroke, thereby changing the compression ratio to adapt to changes in the moisture content of the biomass crushed material.

[0010] A further improvement to the system of the present invention is that it further includes: The biomass briquette conveyor belt is a closed transport system, with a skin covering the outside of the conveyor belt to prevent dust from escaping.

[0011] A further improvement to the system of the present invention is that it further includes: The biomass briquetting and cutting machine can be a CNC cutting machine, a manual cutting machine, or a die-cutting machine.

[0012] This invention provides a method for preparing biomass fuel adaptable to raw materials with different moisture contents, based on the biomass fuel preparation system adapted to raw materials with different moisture contents described in this invention; the method includes the following steps: During the feeding process, the crushed biomass material enters the cavity of the biomass feeder through the pneumatic conveying pipe. Then, the feeding electric push rod pushes forward until the cavity of the biomass feeder coincides with the material tray in the vertical direction. The material tray is lowered to its lowest position by the pull of the picking electric push rod, and the crushed biomass material in the cavity of the biomass feeder falls into the material tray under the action of gravity. Afterward, the biomass feeder returns to its original position by the pull of the feeding electric push rod. During the compression process, the hydraulic press applies hydraulic pressure according to the set hydraulic pressure to compress the biomass pulverized material on the material tray into biomass briquettes. After the compression is completed, the hydraulic press returns to its original position, and the material tray and the biomass briquettes on it move upward under the push of the material picking electric push rod until the upper surface of the material tray is flush with the upper surface of the base. During the unloading process, the biomass feeder is pushed forward by the feeding electric push rod, pushing the biomass briquettes that have been processed in the previous round into the biomass briquette conveyor belt; During the cutting process, the biomass briquette conveyor belt delivers the biomass briquettes to the biomass briquette cutter, which cuts the biomass briquettes into the required shapes and sizes according to production needs.

[0013] A further improvement to the working method of the present invention is that it further includes: During the compression process, the hydraulic pressure of the hydraulic press is calculated based on the moisture content and density of the biomass pulverized material. The initial bulk density, ultimate compacted density, and compaction coefficient of the biomass pulverized material are considered as parameters with statistical fluctuation characteristics, and their relationship satisfies the following formula: + In the formula, The target density of biomass briquettes is kg / m³. 3 ; The initial bulk density of the biomass pulverized material is the statistical average value, in kg / m³. 3; Ultimate compaction density of biomass crushed material Statistical average, kg / m 3 . P The target hydraulic pressure is given in kN. This is the statistical average of the compaction coefficient, which is dynamically adjusted based on the moisture content and type of biomass. This is a correction factor set according to the requirements of compaction consistency or compaction reliability. The statistical fluctuation of compaction pressure is obtained by superimposing the fluctuations of initial bulk density, ultimate compaction density, and compaction coefficient using the first-order error propagation formula, and is expressed in kN. It is the standard deviation of the compaction coefficient, representing the compaction coefficient. k The degree of dispersion caused by fluctuations in raw materials and working conditions during the actual compaction process; It is the standard deviation of the initial bulk density of biomass crushed material, which indicates the degree of dispersion of the initial bulk density of biomass crushed material due to the raw materials; It is the ultimate compaction density of biomass crushed material. The standard deviation represents the degree of dispersion in the ultimate compaction density of biomass crushed material due to fluctuations in raw materials and operating conditions.

[0014] A further improvement to the working method of the present invention is that it further includes: After compression, the forming density of the biomass briquettes is measured. and the target density of biomass briquettes Compare the values ​​and adjust the hydraulic pressure for the next cycle based on the deviation. P After modification, the adjustment relationship satisfies: In the formula, The compressed density of biomass briquettes is expressed in kg / m³. 3 ; This is an adjustment coefficient, the value of which is obtained based on production practice; the larger the value, the faster the adjustment.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The equipment in the system provided by this invention is not easily worn out. Most biomass molding machines on the market rely on molds. During the processing, the holes of the mold are easily blocked and damaged, which requires mold replacement, resulting in increased costs, increased labor intensity for workers, and reduced production efficiency. The system of this invention has no easily worn parts, meets the needs of continuous production, and improves production efficiency.

[0016] 2. The method provided by this invention allows for the modification of the shape and size of the formed blocks. Most biomass molding machines on the market can only produce biomass fuel of one shape or size. If a change is needed, it is necessary to stop production and replace the mold, which is time-consuming and labor-intensive. This invention can process biomass formed blocks into biomass fuel of different shapes and sizes according to different production needs by changing the cutting method of the biomass briquetting machine, thus providing greater production flexibility.

[0017] 3. The method provided by this invention can adapt to biomass pulverized materials with different moisture content. This invention can adjust the compression ratio by adjusting the liquid pressure, so that biomass pulverized materials with different moisture content can be pressed into shape. Attached Figure Description

[0018] Figure 1 This is a biomass fuel preparation system adapted to raw materials with different moisture contents, according to an embodiment of the present invention; The following are explanations of the reference numerals in the diagram: 1. Pneumatic conveying pipeline; 2. Biomass feeder; 3. Electric feeding push rod; 4. Base; 5. Hydraulic press; 6. Material tray; 7. Electric material removal push rod; 8. Biomass briquette conveyor belt; 9. Biomass briquette cutter. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0020] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] The present invention will now be described in further detail with reference to the accompanying drawings: Please see Figure 1 An embodiment of the present invention provides a biomass fuel preparation system adapted to raw materials with different moisture contents, comprising a pneumatic conveying pipeline 1, a biomass feeder 2, a feeding electric push rod 3, a base 4, a hydraulic press 5, a material tray 6, a material picking electric push rod 7, a biomass briquetting conveyor belt 8, and a biomass briquetting cutter 9. The pneumatic conveying pipeline 1 has two pipes connected to the cavity of the biomass feeder 2: one is an air inlet pipe, and the other is an air outlet pipe. The air outlet pipe is equipped with a 10mm mesh screen. The outer wall of the biomass feeder 2 is fixedly connected to the feeding electric push rod 3, allowing it to move synchronously under the push of the feeding electric push rod 3. The feeding electric push rod 3 is rigidly connected to the base 4. The base 4 supports the biomass feeder 2, the feeding electric push rod 3, the hydraulic press 5, and the material tray 6, and provides a horizontal working surface for the above components and prevents vibration. The hydraulic press 5 is rigidly connected to the base. The hydraulic head on the hydraulic press 5 can reciprocate vertically. The material tray 6 is rigidly connected to the material picking electric push rod 7 and can move synchronously under the push of the material picking electric push rod 7. At the lowest point of the material tray 6, it contacts the recess of the base 4. At the highest point, it is flush with the horizontal plane of the base 4. One end of the biomass briquette conveyor belt 8 is close to the boundary of the base 4, which can ensure that the biomass briquettes fall naturally onto the biomass briquette conveyor belt 8. The other end is close to the biomass briquette cutter 9.

[0022] Based on the above-described biomass fuel preparation system adapted to raw materials with different moisture contents, this invention also proposes a method for using the above system, comprising the following steps: During the feeding process, the crushed biomass material enters the cavity of the biomass feeder 2 through the pneumatic conveying pipe 1. Then, the feeding electric push rod 3 pushes forward until the cavity of the biomass feeder 2 coincides with the material tray 6 in the vertical direction. The material tray 6 is pulled down to its lowest point by the material picking electric push rod 7. The crushed biomass material in the cavity of the biomass feeder 2 falls into the material tray 6 under the action of gravity. Then, the biomass feeder 2 returns to its original position under the pull of the feeding electric push rod 3. The compression process requires first determining the target density of the biomass briquettes needed for production. (kg / m 3 The statistical average initial bulk density of biomass pulverized material was obtained based on experimental data. (kg / m3), standard deviation of initial bulk density Statistical average value of ultimate compaction density of biomass crushed material (kg / m3), standard deviation of ultimate compacted density Statistical average of compaction coefficient and the standard deviation of the compaction coefficient Statistical mean and standard deviation The following formula can be used to calculate it: (1) (2) Select the correction factor based on the production qualification rate requirement. Hydraulic press 5 target hydraulic pressure P (kN) can be calculated using the following formula: + (3) (4) After compression, the hydraulic press 5 returns to its original position, and the material tray 6 carries the material. S (m) 2 ), and the height of the bottom of the hydraulic head from the material tray 6 during the compression process of the hydraulic press 5. H (m), calculate the volume of the biomass briquettes. V (m) 3 ): (5) The material tray 6 is equipped with a gravity detector, which can determine the weight of the biomass briquettes. M (kg), combined with the above formula, to calculate the forming density of biomass briquettes. (kg / m 3 ): (6) and with target density (kg / m 3 The hydraulic pressure for the next cycle is determined by comparing the values ​​and correcting for any deviations. P Adjustment coefficients are obtained based on production practice. The regulatory relationship satisfies: (7) Biomass briquettes reach target density (kg / m 3 After that, based on the corrected hydraulic pressure P The target hydraulic pressure formula is modified to achieve high-quality, continuous biomass fuel production.

[0023] After producing qualified biomass briquettes, the material tray 6 and the biomass briquettes on it move upward under the push of the material picking electric push rod 7 until the upper plane of the material tray 6 is flush with the upper plane of the base 4. During the unloading process, the biomass feeder 2 is pushed forward by the feeding electric push rod 3, pushing the biomass briquettes that have been processed in the previous round into the biomass briquette conveyor belt 8; During the cutting process, the biomass briquette conveyor belt 8 delivers the biomass briquette to the biomass briquette cutter 9, which cuts the biomass briquette into the required shape and size according to production needs.

[0024] The method provided by this invention can adapt to biomass pulverized materials with different moisture content. This invention can adjust the compression ratio by adjusting the liquid pressure, so that biomass pulverized materials with different moisture content can be compressed into shape.

[0025] The equipment in the system provided by this invention is not easily worn out. Most biomass molding machines on the market rely on molds. During the processing, the holes in the molds are easily blocked and damaged, requiring mold replacement, which increases costs, increases the labor intensity of workers, and reduces production efficiency. In the system of this invention, none of the components are easily worn out, which meets the needs of continuous production and improves production efficiency.

[0026] The method provided by this invention allows for the formation of biomass briquettes with variable shapes and sizes. Most commercially available biomass molding machines can only produce biomass fuel of one shape or size; changing these shapes requires stopping production to replace the molds, which is time-consuming and labor-intensive. This invention, by changing the cutting method of the biomass briquetting machine, can process biomass briquettes into different shapes and sizes according to different production needs, offering greater production flexibility.

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A biomass fuel preparation system adaptable to raw materials with different moisture contents, characterized in that, include: The system includes a pneumatic conveying pipeline (1), a biomass feeder (2), a feeding electric push rod (3), a base (4), a hydraulic press (5), a material tray (6), a material removal electric push rod (7), a biomass briquetting conveyor belt (8), and a biomass briquetting cutter (9). The pneumatic conveying pipeline (1) is used to transport biomass pulverized material carried by compressed air into the biomass feeder (2). The biomass feeder (2) has a cavity inside for storing the biomass pulverized material. The feeding electric push rod (3) can push the biomass feeder (2) along the plane of the base (4). Reciprocating motion; the base (4) is used to bear weight and keep the working surface level to prevent vibration; the hydraulic press (5) has a hydraulic head that reciprocates in the vertical direction to compress the biomass crushed material into biomass briquettes; the material tray (6) is located below the hydraulic press (5) and the biomass crushed material is placed on the material tray (6); the material picking electric push rod (7) is located below the material tray (6) and pushes the material tray (6) to reciprocate in the vertical direction; the biomass briquette conveyor belt (8) sends the biomass briquettes to the biomass briquette cutter (9).

2. The biomass fuel preparation system adaptable to raw materials with different moisture contents according to claim 1, characterized in that, The pneumatic conveying pipe (1) has two pipes connected to the cavity of the biomass feeder (2), namely the air inlet pipe and the air outlet pipe. The pneumatic conveying pipe (1) carries the biomass pulverized material from the air inlet pipe into the cavity of the biomass feeder (2) through the compressed air, and the compressed air is discharged from the cavity through the air outlet pipe. Due to the high resistance of the pipe here, the denser biomass pulverized material is left here.

3. The biomass fuel preparation system adaptable to raw materials with different moisture contents according to claim 2, characterized in that, The air outlet pipe is equipped with a screen with a aperture of 2-16mm, depending on the size of the crushed material, to prevent large biomass crushed materials from flowing back.

4. The biomass fuel preparation system adaptable to raw materials with different moisture contents according to claim 1, characterized in that, The biomass briquette conveyor belt (8) sends the biomass briquettes produced from the base (4) to the biomass briquette cutter (9). The biomass briquette cutter (9) has great production flexibility and cuts the biomass briquettes into the required shapes and sizes.

5. The biomass fuel preparation system adaptable to raw materials with different moisture contents according to claim 1, characterized in that, The hydraulic press (5) can output a specified hydraulic pressure, thereby changing the compression ratio to adapt to changes in the moisture content of the biomass crushed material.

6. The biomass fuel preparation system adaptable to raw materials with different moisture contents according to claim 1, characterized in that, The biomass briquette conveyor belt (8) is a closed transport system, and the outside of the biomass briquette conveyor belt is covered with a skin to prevent dust from escaping.

7. The biomass fuel preparation system adaptable to raw materials with different moisture contents according to claim 1, characterized in that, The biomass briquetting and cutting machine (9) is a CNC cutting machine, a manual cutting machine, or a die-cutting machine.

8. The working method of the biomass fuel preparation system adapted to raw materials with different moisture contents as described in any one of claims 1-7, characterized in that, include: During the feeding process, the biomass pulverized material enters the cavity of the biomass feeder (2) through the pneumatic conveying pipe (1). Then, the feeding electric push rod (3) pushes forward until the cavity of the biomass feeder (2) coincides with the material tray (6) in the vertical direction. The material tray (6) is pulled down to the lowest point by the material picking electric push rod (7). The biomass pulverized material in the cavity of the biomass feeder (2) falls into the material tray (6) under the action of gravity. Then, the biomass feeder (2) returns to its original position under the pull of the feeding electric push rod (3). During the compression process, the hydraulic press (5) compresses the biomass pulverized material on the material tray (6) into biomass briquettes according to the set hydraulic pressure. After the compression is completed, the hydraulic press (5) returns to its original position. The material tray (6) and the biomass briquettes on it move upward under the push of the material picking electric push rod (7) until the upper plane of the material tray (6) is flush with the upper plane of the base (4). During the unloading process, the biomass feeder (2) is pushed forward by the feeding electric push rod (3) to push the biomass briquettes that have been processed in the previous round into the biomass briquettes conveyor belt (8). During the cutting process, the biomass briquette conveyor belt (8) delivers the biomass briquette to the biomass briquette cutter (9), which cuts the biomass briquette into the required shape and size according to production needs.

9. The working method of the biomass fuel preparation system adapted to raw materials with different moisture contents according to claim 8, characterized in that, In the biomass compression process, the hydraulic pressure of the hydraulic press is calculated based on the moisture content and density of the biomass pulverized material. The initial bulk density, ultimate compaction density, and compaction coefficient of the biomass pulverized material are considered as parameters with statistical fluctuation characteristics, and their relationship satisfies the following formula: + In the formula, The target density of biomass briquettes is kg / m³. 3 ; The initial bulk density of the biomass pulverized material is the statistical average value, in kg / m³. 3 ; Ultimate compaction density of biomass crushed material Statistical average, kg / m 3 ; P Target hydraulic pressure, kN; This is the statistical average of the compaction coefficient, which is dynamically adjusted based on the moisture content and type of biomass. This is a correction factor set according to the requirements of compaction consistency or compaction reliability; The statistical fluctuation of compaction pressure is obtained by superimposing the fluctuations of initial bulk density, ultimate compaction density, and compaction coefficient using the first-order error propagation formula, and is expressed in kN. It is the standard deviation of the compaction coefficient, representing the compaction coefficient. k The degree of dispersion caused by fluctuations in raw materials and working conditions during the actual compaction process; It is the initial bulk density of biomass crushed material. The standard deviation represents the degree of dispersion in the initial bulk density of biomass crushed material due to the raw materials. It is the ultimate compaction density of biomass crushed material. The standard deviation represents the degree of dispersion in the ultimate compaction density of biomass crushed material due to fluctuations in raw materials and operating conditions.

10. The working method of the biomass fuel preparation system adapted to raw materials with different moisture contents according to claim 8, characterized in that, After compression, the forming density of the biomass briquettes is measured. and the target density of biomass briquettes Compare the values ​​and adjust the hydraulic pressure for the next cycle based on the deviation. P After modification, the adjustment relationship satisfies: In the formula, The compressed density of biomass briquettes is expressed in kg / m³. 3 ; This is an adjustment coefficient, the value of which is obtained based on production practice; the larger the value, the faster the adjustment.

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