Biomass gasification system and method with dust removal function

Abstract

The invention relates to a biomass gasification system and method with a dust removal function. The biomass gasification system comprises a gasification furnace, a combustor, a raw material supply module and a dust suction device. And the raw material supply module is used for conveying the crushed greening wastes or other biomass raw materials to the gasification furnace for gasification reaction so as to generate biomass fuel gas. An inlet of the dust suction device is arranged at the position close to an outlet of the raw material supply module and used for sucking entrained dust materials in the process that the raw materials fall into the gasification furnace, and the dust materials comprise wood chips, colloid fragments and other light combustible particles. And an outlet of the dust collection device communicates with an oxygen supply path of the combustor and is used for introducing dust materials into the combustor and mixing the dust materials with the biomass gas for combustion. By constructing a closed-loop path of'dust material suction-backdraft ', coking of the gasification furnace can be remarkably reduced, the gasification efficiency and the temperature rising rate of the combustor can be improved, efficient recycling of dust energy is achieved, and the overall operation stability and the heat energy output efficiency of the system are enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biomass energy, in particular to a biomass gasification system with dust removal function and method, and more particularly to a biomass gasification and heat energy utilization system with dust adsorption and back-burning function, which is suitable for efficient gasification and clean heat energy output of biomass resources such as garden green waste, forestry residues and the like. BACKGROUND

[0002] Biomass energy is a clean and renewable energy, which is widely derived from agricultural and forestry wastes, urban green branches, straws, wood chips and the like. It can be converted into combustible gas through gasification, providing a sustainable alternative solution for heat energy supply. Biomass gasification heat supply system has significant environmental benefits and economic potential in the fields of industrial heat supply, central heating, combined heat and power generation and the like.

[0003] The existing biomass gasification system generally includes a raw material pretreatment unit, a feeding system, a gasification furnace, a combustion device, a heat energy output unit and a waste gas treatment unit and the like. After being crushed, the biomass raw material is continuously fed into the gasification furnace by the feeding system (such as a screw conveyor, a belt conveyor and the like), and sequentially undergoes drying, pyrolysis, oxidation and reduction reaction processes to generate mixed combustible gas (mainly containing CO, H2, CH4 and the like), which is then supplied to the burner for use in steam boilers, hot water boilers or other heat equipment.

[0004] However, in actual application, a large amount of light dust material such as wood chip powder, gum fragments and fine fiber powder is often entrained in the biomass raw material during crushing and conveying. After these dust materials enter the gasification furnace together with the main raw material, the following problems are easily caused: 1. Serious coking: light dust is easily softened and fused at high temperature, and gathers in the gasification furnace wall or the lower part of the material bed to form coke blocks, blocking the gasification channel; 2. Gasification efficiency fluctuation: coking will interfere with the gas flow channel, causing uneven fuel distribution and temperature zone disorder, thereby making the gasification reaction rate and combustible gas composition unstable; 3. Decreased operation reliability: frequent coking requires regular shutdown for coke removal, shortening the system operation cycle; 4. Increased manual maintenance burden: coke removal operation requires manual intervention, increasing labor cost; 5. Insufficient combustion efficiency: the initial fuel gas temperature of the burner is low, which may cause ignition difficulty or lag in the initial thermal response.

[0005] Some improved gasification systems are provided with dust collectors or cyclone separation devices at the outlet of the gasification furnace for purifying combustible gas, but these devices are usually located at the rear end of the fuel gas generation and cannot effectively control the dust material before entering the furnace, thus cannot fundamentally avoid the coking risk, nor can they effectively utilize the energy value of the dust material.

[0006] Therefore, how to actively separate dust from the fuel before entering the gasification reaction without changing the structure of the original gasification furnace, and how to efficiently recycle and utilize the dust in the combustion process, become the key technical problems to improve the operation efficiency and stability of the biomass gasification heating system. SUMMARY

[0007] The present application aims to solve the problem that dust is easy to enter the gasification furnace with the raw material in the existing biomass gasification heating system, which causes coking, reduces the gasification efficiency and increases the operation and maintenance burden, and proposes an improved gasification heating system with reasonable structure, clear path and high energy recovery efficiency. By setting a dust collection device in the raw material supply path, the light dust in the raw material is actively separated before entering the gasification furnace and introduced into the burner for synergistic combustion, which not only effectively reduces the coking frequency of the gasification furnace, but also improves the combustion temperature rising speed and the system thermal energy output efficiency, thereby realizing more efficient and clean utilization of biomass resources and improving the operation stability of the heating system.

[0008] In order to achieve the above technical purpose, the present application adopts the following technical scheme: A biomass gasification system with dust removal function, comprising: A gasification furnace for gasification reaction of biomass raw materials to generate biomass fuel gas; A burner for burning the biomass fuel gas to output heat energy; A raw material supply module, the outlet of which is communicated with the inlet of the gasification furnace, for conveying the crushed green waste or other types of biomass raw materials to the gasification furnace; A dust collection device, including a suction port, a conveying channel and a connecting structure, The suction port is arranged near the outlet area of the raw material supply module or the inlet of the gasification furnace, for sucking the light combustible dust such as dust particles, wood fiber scraps and gum fragments entrained in the raw material during the falling of the raw material into the gasification furnace; The conveying channel of the dust collection device is communicated with the oxygen supply path of the burner, for guiding the dust to the burner for mixed combustion with the biomass fuel gas, Wherein, the dust is separated from the raw material gasification path and introduced into the burner for mixed combustion, Realize high-temperature rapid energy recovery of the dust, reduce the coking risk in the gasification furnace, improve the thermal stability of the gasification reaction, and prolong the continuous operation time of the system.

[0009] Optionally, the dust collection device includes a suction port arranged at the outlet area of the raw material supply module, and the suction port is in a converging flow guiding structure, for gathering and preferentially sucking the light combustible dust.

[0010] Optionally, the dust suction device comprises a dust conveying channel, which guides the dust material into the oxygen supply channel of the combustor through negative pressure or auxiliary fan, so that the dust material forms a stable mixed gas flow with the biomass gas.

[0011] Optionally, the dust suction device is provided with a filter screen or a cyclone guide structure to block large particles, impurities or non-combustible materials that may be mixed in the raw material, so as to prevent the combustor oxygen supply path from being blocked.

[0012] Optionally, the working state of the dust suction device is linked with the running state of the raw material supply module, and the suction is started when the raw material is discharged, and the suction is automatically turned off after the raw material stops discharging.

[0013] Optionally, the connecting pipeline between the dust suction device and the combustor is made of heat-resistant and corrosion-resistant material, and is provided with a bend buffer section to slow down the impact of high-temperature gas back transmission.

[0014] Optionally, the dust material includes but is not limited to wood chips, fiber fragments, gel particles and other combustible light particles, and the dust material can be synergistically combusted with the biomass gas after high-temperature treatment in the combustor, so as to improve the flame starting temperature and combustion efficiency.

[0015] Optionally, the flue gas output by the combustor is provided with a shunt path connected to the dust removal device and the heat exchange module respectively, so as to realize the pollution control and waste heat utilization of the steam boiler flue gas.

[0016] Optionally, the system further comprises a soft water preparation module and a steam heating circuit for heating water by using the heat energy output by the combustor and supplying heat to the outside, and the dust suction device constitutes an efficiency enhancing component of the entire heat energy chain.

[0017] In order to achieve the above technical purpose, the present application also adopts the following technical scheme: A biomass gasification heating method with dust removal function applied to the system of any one of the above, wherein the method comprises the following steps: Step 1: The pulverized green waste or other biomass raw materials are conveyed to the gasification furnace through the raw material supply module, and the dust suction device is arranged at the discharge port and / or the feeding section of the raw material supply module; Step 2: The dust material mixed in the raw material is sucked by the dust suction device during the falling of the raw material into the gasification furnace; Step 3: The dust material sucked is introduced into the oxygen supply path of the combustor through the conveying channel, and is mixed with the biomass gas generated in the gasification process of the raw material; Step 4: The mixed gas is ignited by the combustor for high-temperature combustion, and steam or hot water is output for external use; Step 5: The dust material provides a quick ignition heat source in the combustion process, raises the combustion starting temperature, and inhibits the coking of the gasification furnace, thereby improving the thermal efficiency and operation stability of the system.

[0018] The main beneficial effects of the on-site in-situ calibration device and method for the level gauge of the present application relative to the prior art are: The dust material is extracted from the raw material before entering the gasification furnace, thereby avoiding the aggregation and fusion of the dust in the gasification area from the source, significantly reducing the frequency of coking, and improving the system operation continuity.

[0019] The dust material of the present application is a fine combustible material that can cause local overheating and uneven heat distribution if it enters the gasification furnace. The present application redirects the dust material to the burner recirculation path, making the gasification reaction environment more stable, thereby improving the consistency and heat value level of the combustible gas.

[0020] In traditional gasification systems, dust material often enters the downstream dust removal equipment with the flue gas as waste, and cannot fully release energy. The present application reintroduces it into the high-temperature area of the burner for mixed combustion, fully releases its heat value, realizes "energy closed loop", and improves the overall energy efficiency of the system.

[0021] The dust material of the present application has the characteristics of low heat capacity and easy ignition, and as an auxiliary fuel, it can quickly participate in initial combustion after entering the burner, play a role in combustion support and heat guidance, and solve the problems of slow temperature rise and unstable initial flame of the existing system burner.

[0022] The present application system can significantly prolong the continuous operation time, reduce the shutdown frequency due to coking, and help reduce the cost of manual maintenance, thereby improving the overall economy and industrial adaptability of the system. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The figure is a schematic diagram of the overall structure of the biomass gasification system of the present application; Figure 2 The figure is a schematic diagram of the steps of the biomass gasification heating method of the present application. DETAILED DESCRIPTION

[0024] The specific embodiments of the present application are further described below: First, in the context of the growing demand for clean energy, biomass energy as a clean and renewable energy source is essential for efficient use. The biomass gasification system and method with dust removal function of the present application aim to solve many problems existing in the current biomass gasification heating system, and realize more efficient and clean use of biomass resources and improvement of the operation stability of the heating system. The specific embodiments will be described in detail below.

[0025] As Figure 1 shown in the following detailed description of the modules of the biomass gasification system with dust removal function of the present embodiment: Gasification furnace: The gasification furnace is the core equipment for the gasification reaction of biomass raw materials in the entire system. Its internal structure design needs to meet the condition requirements of biomass raw materials in different reaction stages. For example, the gasification furnace can adopt a fixed bed gasification furnace structure, which has the advantages of good gas-solid contact and stable reaction.

[0026] In actual operation, biomass raw materials enter the gasification furnace from the top and go through the drying, pyrolysis, oxidation and reduction stages in turn from top to bottom.

[0027] Drying stage: After the biomass briquette enters the gasification furnace, it is first heated to release surface moisture. The temperature range of this stage is approximately 100-150°C, and most of the moisture is released under conditions below 105°C. In order to achieve efficient drying, the gasification furnace can be equipped with heating devices such as electric heating wires or gas heating pipes to provide stable heat sources. At the same time, a ventilation opening is provided at the top of the gasification furnace to exhaust a large amount of water vapor generated during the drying process, ensuring the smooth progress of the drying process. For example, for a batch of green waste raw materials with a moisture content of 20%, by controlling the heating temperature and ventilation amount during the drying stage, the moisture content of the raw materials can be reduced to below 10% after about 15-20 minutes.

[0028] Pyrolysis stage: After preliminary drying, the biomass raw materials begin to crack and gasify at a temperature of 400-600°C, releasing volatile matter, including carbon-hydrogen gas, hydrogen, tar, water vapor, carbon monoxide, carbon dioxide, etc. In order to promote the progress of the pyrolysis reaction, a stirring device can be provided in the gasification furnace to ensure that the raw materials are heated more evenly. For example, the stirring device is started every 5 minutes and each stirring lasts for 30 seconds, ensuring that the raw materials are fully reacted during the pyrolysis stage. At the same time, the temperature inside the furnace is monitored in real time by a temperature sensor, and when the temperature deviates from the set range, the heating power is automatically adjusted to ensure that the pyrolysis reaction is carried out at the appropriate temperature.

[0029] Oxidation stage: The pyrolysis products and limited air or oxygen undergo oxidation reaction in the gasification furnace, which is a violent exothermic reaction. In the oxidation zone of the fixed bed gasification furnace, the heat released by combustion can make the temperature reach 1000-1400°C. In order to accurately control the oxidation reaction, the supply amount of air or oxygen needs to be accurately controlled. For example, a flow regulating valve can be used to adjust the flow of air or oxygen in real time according to the temperature and gas composition monitoring data inside the furnace, ensuring that the oxidation reaction can provide enough heat to maintain the subsequent reaction, and also will not cause the gasification efficiency to decrease due to excessive combustion.

[0030] Reduction stage: The reduction reaction located behind the oxidation reaction, the water vapor and CO2 generated by combustion react with the coke to generate H2 and CO. In order to improve the hydrogen production and promote the progress of the water gas reaction, it is necessary to supplement steam (softened water) into the gasifier. The softened water can be uniformly sprayed into the reduction zone through the steam nozzle and fully contacted with the coke for reaction. At the same time, the reduction reaction is an endothermic reaction, and as the reaction proceeds, the temperature continuously decreases, and the reaction rate gradually decreases. Therefore, heating devices need to be provided in the reduction zone to maintain the appropriate reaction temperature, which is about 600-900℃.

[0031] In addition, in order to handle the small amount of tar water formed by about 5% volatile matter in the primary gasification process, a purification device is provided in the gasifier to collect the tar water and return it to the fuel layer in the furnace for secondary gasification pyrolysis, so that all of them are finally converted into gas fuel without remaining wood tar. At the same time, the gasifier adopts a rotary furnace bottom wet slagging method, and the water in the furnace tray (softened water) is used to seal the inside and outside of the furnace. The water in the ash tray is absorbed by the slag, and the water level in the ash tray is lowered in time to supplement water to ensure the sealing of the furnace and no dust is generated. Most of the water in the ash tray is lost in the form of water vapor, and a small part is absorbed by the slag and enters the solid waste. After the slag is discharged, it is directly packed and stored, and the workshop floor does not need to be washed.

[0032] Burner: The burner is used to burn the biomass fuel gas generated by the gasifier and the dust material delivered by the dust collection device to output heat energy. The design of the burner needs to ensure that the biomass fuel gas and the dust material can be fully mixed and stably burned.

[0033] The burner can adopt a premixed combustion structure, that is, before combustion, the biomass fuel gas and the dust material are fully mixed with air in the mixing chamber. The mixing chamber is provided with a spoiler to increase the turbulence degree of the gas and the dust material, so that they are more uniformly mixed. For example, the shape and angle of the spoiler are carefully designed to form a complex flow field of biomass fuel gas, dust material and air in the mixing chamber, ensuring that the three are fully mixed.

[0034] During the combustion process, the flame state is monitored in real time by a flame detector. When the flame appears unstable or extinguishes abnormally, the flame detector feeds back the signal to the control system, which immediately cuts off the gas supply and starts the ignition device to re-ignite. At the same time, the burner is equipped with a temperature sensor to monitor the combustion temperature in real time, and by adjusting the supply amount of gas and air, the combustion temperature is kept within the set range to improve the combustion efficiency and the stability of heat energy output. For example, for biomass fuel gas mainly composed of CO and H2, the combustion temperature is controlled between 1200-1400℃, which can achieve efficient combustion.

[0035] In addition, the flue gas output by the combustor is provided with a shunt path connected to the dust removal device and the heat exchange module, respectively. The path connected to the dust removal device is used to remove particulate matter, sulfides and other pollutants in the flue gas, ensuring that the emissions meet environmental standards; the path connected to the heat exchange module is used to realize the waste heat utilization of the steam boiler flue gas, improving energy utilization. For example, a bag filter is used in the dust removal device, which can effectively remove fine particulate matter in the flue gas; in the heat exchange module, the heat in the flue gas is transferred to cold water through a heat exchanger to produce hot water or steam for heating other process or domestic water.

[0036] Raw material supply module: The raw material supply module is responsible for transporting the crushed green waste or other types of biomass raw materials to the gasification furnace. This module usually includes a storage bin, a conveying device and a control device.

[0037] The storage bin is used to store the crushed biomass raw materials, and its design needs to consider factors such as storage capacity, moisture resistance, ventilation, etc. For example, the storage bin can have a sealed structure with ventilation openings and humidity sensors inside. When the humidity exceeds the set value, the ventilation equipment is automatically started to prevent the raw materials from being damp and deteriorating. At the same time, the capacity of the storage bin is reasonably designed according to the processing capacity of the system and the supply of raw materials to ensure the continuous supply of raw materials.

[0038] The conveying device can be a screw conveyor or a belt conveyor. The screw conveyor has good sealing performance and high conveying efficiency, and is suitable for conveying powdery or small particle biomass raw materials; the belt conveyor is suitable for conveying larger particles or block-shaped raw materials, and has a longer conveying distance. For example, for crushed wood chips and other raw materials, a screw conveyor can be used for conveying; for larger size biomass briquettes, a belt conveyor can be used. The conveying speed of the conveying device can be adjusted by a frequency converter to accurately control the conveying amount of raw materials according to the feeding requirements of the gasification furnace.

[0039] The control device is used to coordinate the operation of the storage bin and the conveying device. For example, when the raw material in the storage bin is below a certain liquid level, the control device sends a signal to notify the feeding equipment to supplement the raw material; when the raw material sensor at the feeding inlet of the gasification furnace detects that the raw material is insufficient, the control device automatically increases the conveying speed of the conveying device to ensure the continuous feeding of the gasification furnace.

[0040] Dust removal device: The dust removal device is a key part of the invention, and its design purpose is to effectively suck the dust carried in the raw materials before they enter the gasification furnace and guide them to be burned together with the biomass gas in the combustor.

[0041] Air intake: The air intake is located in the outlet area of ​​the raw material supply module or near the inlet of the gasification furnace. To more effectively gather and preferentially extract lightweight combustible dust, the air intake adopts a tapered airflow guide structure. This structure concentrates the airflow generated during the raw material's descent, guiding the lightweight dust towards the air intake. For example, the tapering angle of the air intake can be designed from 30° to 60°, adjusted according to the actual raw material's descent speed and the characteristics of the dust, ensuring maximum dust extraction. Simultaneously, the air intake can be equipped with multiple adjustable guide vanes to further optimize the airflow direction and improve dust extraction efficiency.

[0042] Conveying Channel: The dust collection device guides the sucked-up dust to the oxygen supply channel of the burner through a dust conveying channel. To ensure smooth dust conveying, the channel can be operated using negative pressure or an auxiliary fan. When using negative pressure, a vacuum pump is installed at the end of the channel to create a negative pressure environment, drawing in the dust and conveying it to the burner. If an auxiliary fan is used, a fan is installed at an appropriate location in the channel, using positive pressure to blow the dust to the burner. For example, for longer conveying channels, a multi-stage fan relay system can be used to ensure that the dust does not become clogged due to excessive resistance during transport. Furthermore, to ensure a stable mixture of dust and biomass fuel gas, a mixer, such as a Venturi mixer, can be installed at the connection between the burner's oxygen supply channel and the conveying channel, utilizing the Venturi effect to thoroughly mix the dust and fuel gas.

[0043] Filtration and Protection Structure: The dust collection device is equipped with a filter screen or a cyclone guide structure to block large particles, impurities, or non-combustible materials that may be mixed in with the raw materials, preventing them from clogging the oxygen supply path of the burner. The filter screen can be made of stainless steel, with an appropriate mesh size selected according to actual needs. For example, a mesh size of 1-5mm can effectively block large particles without affecting the passage of dust. The cyclone guide structure separates large particles by causing the airflow to rotate and using centrifugal force. For example, spiral blades are installed in the channel, causing the airflow to form a spiral motion. Large particles are thrown against the channel wall under centrifugal force, thus achieving separation from the dust.

[0044] Operation Control: The operating status of the dust collection device is linked to the operating status of the raw material supply module. When the raw material supply module starts feeding, the control system detects the operating signal of the conveyor equipment and automatically activates the suction function of the dust collection device. When the raw material feeding stops, the control system detects the stop signal of the conveyor equipment and, after a certain delay (e.g., 1-2 minutes to ensure that residual dust is completely removed), automatically shuts off the suction function. This linked control method not only effectively removes dust but also avoids ineffective operation of the dust collection device, saving energy.

[0045] Connecting Duct: The connecting duct between the vacuum cleaner and the burner is made of heat- and corrosion-resistant materials, such as stainless steel or ceramic composites, to withstand high-temperature, high-humidity environments and the presence of potentially corrosive gases. Simultaneously, to mitigate the impact of high-temperature gas backflow, the connecting duct is equipped with a bend buffer section. The bending angle and length of the bend buffer section are designed according to actual conditions; for example, the bending angle can be set to 90°-180°, and the length to be 1-2 meters. By changing the airflow direction and increasing the airflow path length, the impact of high-temperature gas is effectively buffered, protecting the vacuum cleaner and related equipment.

[0046] Detailed implementation of the system operation flow in this embodiment 1. Raw material preparation and transportation First, biomass raw materials such as green waste and forestry residues are crushed to a particle size suitable for gasification. For example, branches and straw are crushed into particles with a diameter of about 5-10 mm using a crusher. The crushed raw materials are then temporarily stored in the storage bin of the raw material supply module.

[0047] When the system starts, the conveying equipment of the raw material supply module begins to operate, transporting the raw materials in the storage bin to the feed inlet of the gasification furnace. The conveying speed of the equipment is adjusted according to the feeding requirements of the gasification furnace to ensure that the raw materials can enter the gasification furnace evenly and stably. During the conveying process, the dust collection device is linked to the raw material supply module. When the conveying equipment starts, the suction port of the dust collection device begins to operate, sucking up the dust and dirt carried by the raw materials during their descent.

[0048] 2. Dust suction and conveying The dust collection device's suction port utilizes its constricted airflow structure to effectively gather and extract lightweight combustible dust materials, such as sawdust, fiber fragments, and viscous particles, as the raw materials fall into the gasification furnace. The suction power of the suction port can be adjusted according to actual conditions. For example, by adjusting the fan speed or negative pressure value, the air velocity at the suction port can be maintained at 5-10 m / s to ensure that sufficient dust materials are extracted.

[0049] The extracted dust is guided through a conveying channel to the oxygen supply channel of the burner under negative pressure or by an auxiliary fan. During the conveying process, a filter screen or cyclone guide structure filters and separates the dust, preventing large particles, impurities, or non-combustible materials from entering the burner. Simultaneously, pressure and flow sensors installed on the conveying channel monitor the conveying pressure and flow rate of the dust in real time to ensure stable conveying. If abnormal pressure or low flow occurs, the control system will issue an alarm and take corresponding measures, such as cleaning the filter screen or checking the fan's operating status.

[0050] 3. Gasification reaction Biomass feedstock undergoes four reaction stages in sequence—drying, pyrolysis, oxidation, and reduction—in a gasifier to generate biomass fuel gas.

[0051] Drying Stage: As mentioned earlier, the furnace temperature is raised to 100-150℃ using a heating device, causing the moisture in the raw materials to gradually evaporate. The power of the heating device is automatically adjusted according to the moisture content of the raw materials and the feed rate to ensure the drying effect. Simultaneously, water vapor is promptly discharged through ventilation openings to maintain a dry environment inside the furnace.

[0052] Pyrolysis stage: The dried raw materials undergo pyrolysis at a temperature of 400-600℃. A stirring device and temperature control device ensure that the raw materials react fully during the pyrolysis stage, releasing volatile components. The stirring frequency and intensity can be adjusted according to the characteristics of the raw materials. For example, for harder raw materials, the stirring frequency and intensity can be appropriately increased to ensure more uniform heating.

[0053] Oxidation stage: The pyrolysis products undergo an oxidation reaction with limited air or oxygen at a high temperature of 1000-1400℃, releasing a large amount of heat. The stable progress of the oxidation reaction is ensured by precisely controlling the supply of air or oxygen. Simultaneously, a temperature sensor monitors the temperature of the oxidation zone in real time; when the temperature is too high, the air or oxygen supply is appropriately reduced; when the temperature is too low, the supply is increased to maintain a suitable reaction temperature.

[0054] Reduction Stage: In the reduction zone, by supplementing with steam and using a heating device, the steam and CO2 produced by combustion react with the coke to generate H2 and CO. The amount of steam supplied is adjusted according to the reaction requirements, and the heating device ensures that the reduction reaction takes place within a temperature range of 600-900℃. Precise control of the reduction stage improves the quality and yield of biomass fuel gas.

[0055] 4. Hybrid Combustion and Heat Output Biomass fuel gas from the gasifier is mixed with dust transported by a dust collection device and then combusted in the burner after being thoroughly mixed with air. The burner's premixing structure and mixer ensure uniform mixing of fuel gas, dust, and air. During combustion, a flame detector monitors the flame status in real time, a temperature sensor monitors the combustion temperature, and the control system automatically adjusts the supply of fuel gas, air, and dust based on the monitoring data to ensure stable combustion, high efficiency, and stable heat output.

[0056] The heat generated by combustion is used to heat soft water to produce steam or hot water, which is then supplied to the outside through a steam heating loop. For example, in a steam boiler, the high-temperature flue gas produced by combustion transfers heat to the soft water through a heat exchanger, raising the water temperature and converting it into steam. After being distributed by a steam distributor, the steam is transported to the heat-using unit through pipelines, where it undergoes indirect heat exchange with the unit's cold water, cold air, etc., to achieve heating. Simultaneously, the condensate after heat exchange is returned to the boiler through pipelines for recycling, improving energy efficiency.

[0057] 5. System monitoring and maintenance The entire system is equipped with a comprehensive monitoring system, including temperature sensors, pressure sensors, flow sensors, flame detectors, etc., to monitor the operating parameters of each part of the system in real time. The monitoring system transmits the collected data to the control system, which analyzes and processes the data. When abnormal parameters are detected, the control system promptly issues an alarm and takes corresponding control measures, such as adjusting equipment operating parameters and activating backup equipment, to ensure the safe and stable operation of the system.

[0058] In addition, regular system maintenance and upkeep are essential, including checking equipment operation, cleaning filters, and replacing worn parts. For example, the dust collection device's filter should be cleaned or replaced every month to ensure effective dust collection; the internal structure of the gasification furnace should be inspected every three months to check for coking, wear, or other issues, and addressed promptly to extend the equipment's lifespan.

[0059] like Figure 2 As shown in the figure, the detailed implementation steps of the heating method of the biomass gasification system with dust removal function in this embodiment are as follows: Step 1: Setting up raw material conveying and dust collection devices The crushed green waste or other biomass raw materials are transported from the storage silo to the gasification furnace feed inlet via the conveying equipment of the raw material supply module. A dust collection device is installed at the discharge port and / or feed section of the raw material supply module to ensure effective extraction of entrained dust during the material's descent. For example, for a screw conveyor, a suction port for the dust collection device can be installed below its discharge port, ensuring close alignment with the material's descent path to improve dust collection efficiency.

[0060] Step 2: Dust extraction As the raw materials fall into the gasification furnace, the dust extraction device's suction port begins operation, utilizing its constricted airflow structure and appropriate suction force to extract dust entrained in the raw materials. The suction force of the suction port can be adjusted according to the characteristics of the raw materials and the dust content. For example, for raw materials with a high dust content, the suction force is appropriately increased; for lightweight raw materials, the suction force is appropriately decreased to avoid extracting too much material. Simultaneously, by adjusting the angle of the guide vane at the suction port, the airflow direction is optimized to ensure maximum dust extraction.

[0061] Step 3: Dust Material Introduction and Mixing The extracted dust is conveyed through a transport channel and, under negative pressure or with an auxiliary fan, is introduced into the oxygen supply path of the burner. During this process, a mixer ensures that the dust is thoroughly mixed with the biomass fuel gas generated during the gasification of the raw materials. The structure and parameters of the mixer are designed according to actual conditions. For example, the throat diameter and length of the Venturi mixer need to be optimized based on factors such as the flow rate and velocity of the fuel gas and dust to ensure uniform mixing and a stable mixed airflow.

[0062] Step 4: High-temperature combustion and heating The mixed gas is ignited by a burner for high-temperature combustion. The burner's ignition device employs either electronic or gas ignition to ensure reliable ignition. During combustion, flame detectors and temperature sensors monitor the flame state and combustion temperature in real time. The control system automatically adjusts the supply of gas, air, and dust based on the monitoring data, ensuring stable combustion and improving combustion efficiency. The heat generated by combustion is used to heat soft water, producing steam or hot water, which is then supplied to the outside through a steam heating circuit. For example, in a steam boiler, the high-temperature flue gas generated by combustion transfers heat to soft water through a heat exchanger, converting the soft water into steam. The steam is then piped to the heat-consuming unit to provide heating.

[0063] Step 5: System Optimization and Stable Operation During combustion, the dust, with its low heat capacity and easy ignition, provides a rapid ignition heat source, increasing the initial combustion temperature and making combustion more stable. Simultaneously, because the dust is separated from the main gasification path of the raw materials, it avoids agglomeration and melting within the gasifier, inhibiting coking and thus improving the system's thermal efficiency and operational stability. Furthermore, by continuously monitoring and analyzing system operating parameters in real time, the system's operating status is optimized, such as adjusting the raw material conveying speed, the suction power of the dust collector, and the gas-air ratio of the burner, ensuring long-term stable and efficient operation. For example, based on monitoring data of combustion temperature and flue gas composition, the supply of gas and air is adjusted in a timely manner to ensure more complete combustion and improve thermal energy output efficiency; based on monitoring of temperature distribution and coking conditions within the gasifier, the operating parameters of the dust collector are adjusted to further reduce coking.

[0064] Meanwhile, the system is regularly inspected and maintained, including checking for coking inside the gasifier, cleaning the dust collection device filter, and cleaning the burner nozzles. Any problems found are dealt with promptly, such as cleaning coking material inside the gasifier, replacing clogged filters, and adjusting the position of the burner nozzles, to ensure the normal operation of all system components and extend the system's service life.

[0065] During long-term operation, the system can be upgraded and improved according to changes in actual heating demand and raw material characteristics. For example, if heating demand increases, the size of the gasifier and burner can be appropriately increased to improve the system's capacity; if the type or characteristics of the raw materials change, the structure of the dust collection device's air inlet, the parameters of the conveying channel, and the combustion parameters of the burner can be adjusted accordingly to adapt to the new raw material conditions and ensure that the system always maintains a good operating condition.

[0066] Through the detailed embodiments described above, the biomass gasification system and method with dust removal function of the present invention can effectively solve the problems existing in the current biomass gasification heating system, realize the efficient utilization of biomass resources and the stable operation of the heating system, and provide a reliable technical solution for the development and application of biomass energy. In practical applications, the various parts of the system can be flexibly configured and adjusted according to different needs and conditions to meet diverse production and heating needs, and has broad application prospects and significant economic and environmental benefits.

[0067] Furthermore, with continuous technological development and advancement, intelligent control technology and big data analytics can be incorporated into the system. Intelligent control technology enables automated operation and intelligent adjustment of the system, automatically optimizing system parameters based on real-time monitoring data to improve system efficiency and stability. Big data analytics, on the other hand, analyzes data accumulated over long-term system operation, uncovering potential optimization opportunities, predicting equipment failures, and enabling proactive maintenance and upkeep, further reducing system operating costs and improving reliability.

[0068] For example, by utilizing intelligent control technology, the system can automatically adjust the raw material conveying speed, burner combustion power, and dust collection device operating status based on factors such as outdoor temperature and heating demand, achieving precise energy supply and efficient utilization. Through big data analysis, in-depth research can be conducted on the gasification characteristics, coking conditions, and relationships between system operating parameters of different types of biomass raw materials, providing a more scientific basis for system optimization. Simultaneously, equipment fault early warning models can be established to predict potential faults based on trends in equipment operating parameters, promptly notifying maintenance personnel to handle them and avoiding downtime and production losses due to equipment failure.

[0069] The biomass gasification system and method with dust removal function of the present invention not only has important practical value at present, but also has the potential for further optimization and improvement in the future with the continuous development of related technologies, which will make a greater contribution to the development of the biomass energy field.

[0070] In summary, by installing a dust collection device at the raw material feeding port, the present invention removes lightweight dust materials such as wood chips and glue fragments from the raw materials before they enter the gasifier, thereby preventing these dust particles from accumulating and melting in the gasification area, significantly reducing the frequency of coking, and improving the continuity of system operation.

[0071] The dust material of this invention, being a finely broken combustible material, is prone to causing localized overheating and uneven heat distribution if it enters the gasifier. This invention addresses this by redirecting the dust material to the burner's recirculation path, thereby stabilizing the gasification reaction environment and improving the consistency and calorific value of the combustible gas.

[0072] In traditional gasification systems, dust is often treated as waste and sent to downstream dust removal equipment along with the gas, failing to fully release its energy. This invention reintroduces the dust into the high-temperature zone of the burner for mixing and combustion, fully releasing its calorific value, achieving an "energy closed loop," and improving the overall energy efficiency of the system.

[0073] The dust material of this invention has the characteristics of low heat capacity and easy ignition. After entering the burner as auxiliary fuel, it can quickly participate in the initial combustion, playing a role in combustion assistance and heat guidance, thus solving the problems of slow burner temperature and unstable initial flame in existing systems.

[0074] The system of this invention can significantly extend continuous operation time and reduce the number of shutdowns due to frequent furnace cleaning caused by coking by reducing coking. This helps to reduce manual maintenance costs and improve the overall economic efficiency and industrial adaptability of the system.

[0075] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A biomass gasification system with dust removal function, characterized in that, include: A gasifier is used to gasify biomass feedstock to produce biomass fuel gas. A burner for burning the biomass fuel gas to output heat energy; The raw material supply module has its outlet connected to the feed inlet of the gasification furnace, and is used to transport the crushed green waste or other types of biomass raw materials to the gasification furnace. The vacuuming device includes an air intake, a conveying channel, and connecting structures. Its air intake is located in the outlet area of ​​the raw material supply module or near the feed inlet of the gasification furnace, and is used to suck up light combustible dust such as dust particles, wood fiber chips, and glue fragments carried in the raw material during the process of the raw material falling into the gasification furnace. The dust collection device's conveying channel is connected to the burner's oxygen supply path, and is used to guide the dust material into the burner to burn together with the biomass fuel gas. In this process, the dust is separated from the main gasification path of the raw materials and introduced into the burner for mixing and combustion. This enables rapid high-temperature energy recovery from the dust material, reduces the risk of coking in the gasification furnace, improves the thermal stability of the gasification reaction, and extends the continuous operating time of the system.

2. The system according to claim 1, characterized in that, The dust collection device includes an air intake located in the outlet area of ​​the raw material supply module. The air intake has a constricted flow guide structure for collecting and preferentially extracting lightweight combustible dust.

3. The system according to claim 2, characterized in that, The dust collection device includes a dust conveying channel, which guides the dust to the oxygen supply channel of the burner through negative pressure or an auxiliary fan, so that the dust and biomass gas form a stable mixed airflow.

4. The system according to claim 3, characterized in that, The dust collection device is equipped with a filter screen or a swirling guide structure to block large particles, impurities or non-combustible materials that may be mixed in with the raw materials, so as to prevent clogging of the oxygen supply path of the burner.

5. The system according to claim 4, characterized in that, The working status of the dust collection device is linked to the operating status of the raw material supply module. The suction is activated when the raw material is fed and automatically turned off when the raw material stops being fed.

6. The system according to claim 5, characterized in that, The connecting pipe between the dust collection device and the burner is made of heat-resistant and corrosion-resistant material, and is equipped with a bend buffer section to reduce the impact of high-temperature gas backflow.

7. The system according to claim 6, characterized in that, The dust material includes, but is not limited to, wood chips, fiber fragments, adhesive microparticles and other combustible lightweight particles. After being treated at high temperature in the burner, the dust material can synergistically assist combustion with biomass gas, thereby improving the flame initiation temperature and combustion efficiency.

8. The system according to claim 7, characterized in that, The flue gas output from the burner is provided with a diversion path, which is connected to a dust removal device and a heat exchange module respectively, in order to realize pollution control and waste heat utilization of the flue gas from the steam boiler.

9. The system according to claim 8, characterized in that, The system also includes a soft water preparation module and a steam heating circuit, which are used to heat water using the heat energy output from the burner and supply heat to the outside. The dust collection device constitutes an efficiency enhancement component of the entire thermal energy chain.

10. A biomass gasification heating method with dust removal function, applied to the system described in any one of claims 1-9, characterized in that, Includes the following steps: Step 1: The crushed green waste or other biomass raw materials are transported to the gasification furnace through the raw material supply module, and a dust collection device is installed at the discharge port and / or feeding section of the raw material supply module. Step 2: During the process of the raw material falling into the gasification furnace, the dust suction device sucks up the dust entrained in the raw material; Step 3: The dust material obtained by suction is introduced into the oxygen supply path of the burner through the conveying channel and mixed with the biomass gas generated during the gasification process of the raw materials; Step 4: The mixed gas is ignited by the burner for high-temperature combustion, and steam or hot water is output for external use; Step 5: During the combustion process, the dust material provides a rapid ignition heat source, increases the combustion initiation temperature, and inhibits coking in the gasification furnace, thereby improving the thermal efficiency and operational stability of the system.

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