Automatic feeding method and system for biomass gasifier

Abstract

The application discloses a kind of biomass gasification furnace automatic feeding method and system, it is related to gasification furnace automatic feeding technical field, including the following steps: raw material detection screening with humidity, metal impurities and size are inquired by multiple sensors, material level monitoring temporary storage warehouse, feed quantity calculation depends on gasification furnace parameter, neural network and fuzzy algorithm control motor or frequency precision feeding, feed uniformity relies on special feeder and airflow auxiliary, according to experimental proportion, raw material pretreatment is broken and dried, control parameter and hot air flow, energy recycling heat exchanger, preheating gas and power generation, according to formula parameter control emission, emission monitoring control, exceed standard according to coefficient to adjust operating parameter, fault detection early warning, monitor component state, abnormal early warning self-diagnosis and inform.The application improves the precision and stability of feeding, guarantees raw material quality and equipment safety, optimizes the uniformity of feeding, realizes energy recovery and environmental protection emission reduction, improves energy conversion efficiency, reduces equipment maintenance cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic feeding of biomass gasification furnaces, and in particular to a method and system for automatic feeding of biomass gasification furnaces. BACKGROUND

[0002] With the growing global demand for clean energy and concerns about the environmental impact of traditional fossil fuels, biomass energy as a renewable and low-carbon energy form is increasingly valued. Biomass gasification technology is one of the important ways to utilize biomass energy, which can convert biomass raw materials into combustible gas and be used in power generation, heating, gas supply and other fields.

[0003] However, during the operation of biomass gasification furnaces, there are many technical problems in the automatic feeding process. Traditional feeding methods often rely on manual operation or simple mechanical feeding devices, making it difficult to accurately control the amount of feeding. This leads to unstable reactions in the gasification furnace. When the amount of feeding is too much, incomplete gasification will occur, producing a large amount of tar and unburned solid residues, reducing energy conversion efficiency and increasing the difficulty and cost of subsequent processing. While insufficient feeding cannot meet the normal operation requirements of the gasification furnace, affecting the gas production rate and equipment capacity.

[0004] In addition, the quality of biomass raw materials varies greatly, and factors such as moisture content, size and possible metal impurities can significantly affect the gasification process. High-moisture raw materials will absorb a large amount of heat for water evaporation, reducing the gasification reaction temperature and making the reaction difficult to continue efficiently; oversized or undersized raw materials may cause uneven feeding, causing local abnormal reactions; metal impurities entering the gasification furnace may damage the equipment inside the furnace, affecting the service life and operation safety of the equipment.

[0005] Furthermore, existing feeding systems lack effective measures to ensure uniformity of feeding. Uneven feeding will cause uneven distribution of materials in the gasification furnace, forming local high or low temperature areas, which not only affects the stability and efficiency of the gasification reaction, but also may cause problems such as slagging and clogging in the furnace, increasing equipment maintenance costs and downtime.

[0006] In terms of energy utilization and environmental protection, the traditional biomass gasification furnace feeding system lacks effective energy recycling mechanisms, and a large amount of waste heat is wasted. At the same time, the monitoring and control ability of the emission is insufficient, which is easy to cause environmental pollution and cannot meet the increasingly strict environmental protection requirements. Therefore, it is of great practical significance to develop an efficient, intelligent and environmentally friendly biomass gasification furnace automatic feeding method and system, which can effectively solve the above problems and promote the further development and widespread application of biomass gasification technology. SUMMARY

[0007] The biomass gasification furnace automatic feeding method and system provided by the application can solve the problems in the prior art.

[0008] In order to achieve the above-mentioned purpose, the application adopts the following technical scheme: a biomass gasification furnace automatic feeding method, comprising the following steps:

[0009] S1, raw material detection and screening step: a plurality of sensors are used to detect the biomass raw material, including a humidity sensor to detect the humidity of the raw material, a capacitive humidity sensor, a metal detector to detect metal impurities in the raw material, an electromagnetic induction type metal detector, and a size screening device to screen the raw material meeting the size requirements of the gasification furnace feed inlet;

[0010] The temporary storage bin has a material level monitoring function, and an ultrasonic level meter or a radar level meter is used, and when the material level is lower than the set lower limit value, a raw material replenishment signal is triggered;

[0011] S2, feeding amount calculation and control step: according to the real-time operation parameters of the gasification furnace, the required biomass feeding amount is calculated through the built-in intelligent algorithm, the algorithm is based on the gasification furnace operation model established based on big data analysis, the intelligent algorithm adopts a combination of neural network algorithm and fuzzy control algorithm, the learning rate of the neural network algorithm is η, the initial value is 0.01, and the learning rate is adjusted according to the change of the loss function L in the training process, when the descending amplitude of L is less than δ after continuous k iterations, k=5, δ=0.01, η=η×0.5, and the control rule of the fuzzy control algorithm is determined based on expert experience and experimental data;

[0012] The motor speed or conveying frequency of the feeding device is controlled to accurately adjust the feeding amount, so that the feeding amount and the operation demand of the gasification furnace are accurately matched;

[0013] S3, feeding uniformity guarantee step: a screw feeder or a vibrating feeder is used for feeding operation, and the internal structure of the feeder is designed, specifically: the pitch of the screw blade is gradually changed or the amplitude adjustment function of the vibrating plate, so that the biomass raw material is uniformly distributed in the reaction area of the gasification furnace;

[0014] In the feeding process, an appropriate amount of inert gas or air is injected into the feeding channel through an airflow auxiliary device, and the proportional relationship between the airflow flow rate Q of the airflow auxiliary device and the feeding amount M is determined through experiments, and the adjustment range of the proportional coefficient is between 0.1 and 1;

[0015] S4, raw material pretreatment optimization step: the screened biomass raw material is crushed, the particle size of the crushed raw material meets the reaction requirements of the gasification furnace, a jaw crusher or a hammer crusher is used, and the crushing ratio of the crusher is adjustable between 5 and 20;

[0016] The broken raw materials are dried by a hot air circulation system. The hot air flow is calculated according to the volume and humidity of the raw materials, and the calculation formula is , wherein V is the hot air flow, m is the mass of the raw materials, H1 is the initial humidity of the raw materials, H2 is the target humidity, C is the specific heat capacity of air, T1 is the initial temperature of the hot air, and T2 is the exhaust temperature of the hot air;

[0017] S5, energy recovery and utilization step: during the operation of the gasifier, the heat in the high-temperature flue gas is recovered through a heat exchanger. Part of the recovered heat is used to preheat the air or inert gas entering the gasifier, and the preheating temperature can be raised to 100-300°C. The calculation formula is , wherein T p is the temperature of the preheated gas, T i is the initial gas temperature, Q r is the recovered heat, m a is the mass flow of the gas, and C a is the specific heat capacity of the gas. The other part is used to drive a power generation device to generate electricity, and the electricity generation efficiency is between 10% and 30%. The generated electricity can be supplied to the motors and other equipment in the feeding system;

[0018] S6, emission monitoring and control step: real-time monitoring of the emissions of the gasifier, including carbon monoxide, carbon dioxide, and particulate matter. High-precision gas sensors and particulate matter sensors are used. When the concentration of the emissions exceeds the environmental protection standard, the operating parameters of the gasifier are adjusted. The carbon monoxide concentration adjustment coefficient is β, the carbon dioxide concentration adjustment coefficient is γ, and the particulate matter concentration adjustment coefficient is ε. The adjustment coefficient size is determined according to the over-standard concentration of the emissions. The adjustment amplitude of the feeding amount is calculated by changing the feeding amount, and the calculation formula is , wherein △M is the adjustment amplitude of the feeding amount, M0 is the initial feeding amount, C CO is the over-standard concentration of carbon monoxide, C CO2 is the over-standard concentration of carbon dioxide, and C PM is the over-standard concentration of particulate matter;

[0019] S7, fault detection and early warning step: real-time monitoring of the key components of the feeding system. The motor working current is monitored by a current sensor, and the temperature of the key parts is monitored by a temperature sensor. When an abnormal situation is detected, a fault early warning signal is immediately sent out;

[0020] The fault early warning signal is sent to the operator through various ways such as audible and visual alarms, short message notifications, or system pop-up windows. It also has a fault self-diagnosis function. When the fault early warning signal is sent out, the working current I deviates from the normal current I0 by more than β, β = 0.2I0, and the temperature T deviates from the normal working temperature T0 by more than γ, γ = 5°C. The system automatically diagnoses the fault cause and provides corresponding maintenance recommendations.

[0021] Further, in the raw material detection and screening step, the humidity sensor uses a capacitive humidity sensor, and the relationship between the capacitance change and humidity is determined by a calibration curve, and the fitting degree of the calibration curve is not less than 98%.

[0022] Further, in the feed quantity calculation and control step, the intelligent algorithm uses a combination of neural network algorithm and fuzzy control algorithm, the neural network algorithm learns and predicts the gasifier operation data, and the fuzzy control algorithm accurately controls the feed quantity according to the prediction result.

[0023] Further, in the feed uniformity guaranteeing step, the proportional relationship between the airflow flow of the airflow auxiliary device and the feed quantity is determined through experiments, the adjustment range of the proportional coefficient is between 0.1 and 1, and flexible adjustment is made according to different characteristics of the biomass raw materials.

[0024] Further, in the energy recovery and utilization step, the heat exchanger uses a high-efficiency finned heat exchanger, the fin structure of which is optimized and designed to increase the heat exchange area, and the calculation formula is S=n×l×w×cosθ, wherein S is the heat exchange area, n is the number of fins, l is the fin length, w is the fin width, and cosθ is the angle between the fin and the airflow direction, and the material of the heat exchanger is selected from alloy materials that are resistant to high temperature and corrosion.

[0025] Further, a biomass gasifier automatic feeding system is provided, which comprises:

[0026] A raw material detection and screening device, which comprises a humidity sensor, a metal detector, a size screening device, and a temporary storage bin, is used for detecting, screening, and temporarily storing the biomass raw materials, and the components work cooperatively;

[0027] A feed quantity calculation and control unit, which is composed of a data acquisition module, an intelligent algorithm module, and a control execution module, acquires the gasifier operation parameters, calculates the feed quantity according to the operation parameters, and controls the operation of the feeding device;

[0028] A feed uniformity guaranteeing mechanism, which is provided with a screw feeder or a vibrating feeder and an airflow auxiliary device, guarantees the uniform distribution of the biomass raw materials in the gasifier through the feeders and the airflow auxiliary device;

[0029] A raw material pretreatment optimization module, which comprises a jaw crusher or a hammer crusher and a hot air circulating drying system, is used for crushing and drying the biomass raw materials to make the particle size and humidity of the raw materials meet the requirements of the gasifier reaction;

[0030] An energy recycling module, which is composed of a heat exchanger, a preheating pipeline and a power generation device, the heat exchanger recycles the high-temperature flue gas heat of the gasifier, the preheating pipeline transfers the heat to the air or inert gas entering the gasifier, and the power generation device generates power by using the recycled heat and supplies it to the system equipment;

[0031] An emission monitoring and regulation module, which is equipped with high-precision gas sensors and particulate matter sensors, is used to monitor the concentration of the gasifier emissions, and when the concentration exceeds the standard, the operation parameters of the gasifier are adjusted for regulation to ensure that the emissions meet environmental protection requirements;

[0032] A fault detection and early warning module, which is connected to the key components of the feeding system, monitors the working state in real time, and sends an early warning signal and performs preliminary fault diagnosis when a fault occurs.

[0033] Further, the metal detector in the raw material detection and screening device uses an electromagnetic induction type metal detector, which has a working frequency of 5 kHz to 100 kHz, and can detect different types of metal impurities, with a detection depth of not less than 5 cm for iron, copper and aluminum.

[0034] Further, the data acquisition module in the feeding amount calculation and control unit uses a high-precision sensor, and the data acquisition frequency of the sensor is adjusted between 1 Hz and 10 Hz to accurately obtain the running parameters of the gasifier in real time.

[0035] Compared with the prior art, the present application has the following advantages:

[0036] Through accurate raw material detection and screening, intelligent feeding amount calculation and control, the feeding amount can be accurately adjusted according to the real-time running parameters of the gasifier, the error is controlled within a small range, the gasification reaction is stable and efficient, the energy conversion efficiency is effectively improved, and compared with the traditional feeding method, the energy conversion efficiency can be improved by 20%-30%.

[0037] Strict detection and screening of raw material humidity, metal impurities and size can avoid abnormal gasification reaction and equipment damage caused by raw material problems, prolong the service life of the equipment, reduce the equipment maintenance cost, and the equipment maintenance frequency can be reduced by 30%-50%.

[0038] The specially designed feeder structure and airflow auxiliary device make the raw materials uniformly distributed in the gasifier, reduce the local reaction abnormality and slagging and plugging phenomenon, improve the continuity and reliability of the gasifier operation, and the equipment operation stability is improved by 40%-60%.

[0039] The energy recycling module effectively recycles waste heat, reduces system energy consumption, and partially realizes self-sufficiency; the emission monitoring and regulation module can monitor and regulate the concentration of emissions in real time, so that it meets the environmental protection standards, reduces the pollution to the environment, and the compliance rate of environmental protection indicators can reach more than 95%. BRIEF DESCRIPTION OF DRAWINGS

[0040] Fig. 1 A schematic block diagram of a biomass gasification furnace automatic feeding method according to the present application is shown in the figure;

[0041] Fig. 2 A schematic block diagram of a biomass gasification furnace automatic feeding system according to the present application is shown in the figure. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0043] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0044] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited. In addition, the terms "mounting", "connecting", "connecting" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances, and the present application will be further described in detail with reference to the drawings.

[0045] Referring to Figs. 1-2 A biomass gasification furnace automatic feeding method, comprising the following steps:

[0046] S1, raw material detection and screening step: a variety of sensors are used to detect the biomass raw material, including a humidity sensor to detect the humidity of the raw material with an accuracy of within ±3%, a capacitive humidity sensor is used, the relationship between its capacitance change and humidity is determined through a specific calibration curve, the fitting degree of the calibration curve is not less than 98%, a metal detector is used to detect metal impurities in the raw material with a detection sensitivity of not less than 0.5 grams, an electromagnetic induction type metal detector is used, its working frequency is adjustable between 5 kHz and 100 kHz, the detection depth of common metals such as iron, copper and aluminum is not less than 5 cm, a size screening device is used to screen raw materials that meet the size requirements of the gasification furnace feed port, the screening accuracy is not less than 95%, and the qualified raw materials are transported to the temporary storage bin.

[0047] The temporary storage bin has a material level monitoring function, an ultrasonic level meter or a radar level meter is used, the monitoring accuracy is within ±5 cm, when the material level is lower than the set lower limit value, a raw material replenishment signal is triggered to ensure the continuity of the feeding process.

[0048] S2, feeding amount calculation and control step: according to the real-time running parameters of the gasification furnace, such as power, temperature, pressure, etc., the required biomass feeding amount is calculated through the built-in intelligent algorithm. The algorithm is based on the gasification furnace operation model established by big data analysis, the model training data amount is not less than 500 groups, covering operation data under different working conditions, the error of calculated feeding amount is not more than ±10%. The intelligent algorithm adopts a combination of neural network algorithm and fuzzy control algorithm, the learning rate of neural network algorithm is η, the initial value is 0.01, which is adjusted according to the change of loss function L during training, when the descending amplitude of L is less than δ for continuous k iterations (k=5, δ=0.01), η=η×0.5, the control rule of fuzzy control algorithm is determined based on expert experience and experimental data, so that the control effect is more stable and accurate, and the system response time is shortened by not less than 20%.

[0049] The motor speed or conveying frequency of the feeding device is controlled to accurately adjust the feeding amount, the motor speed adjustment accuracy is within ±5 revolutions / minute, the conveying frequency adjustment accuracy is within ±0.1 hertz, and the accurate matching of the feeding amount and the running demand of the gasification furnace is realized.

[0050] S3, feeding uniformity guarantee step: a screw feeder or a vibrating feeder is used for feeding operation, the internal structure of the feeder is specially designed, such as the pitch gradient of the screw blade or the amplitude adjustment function of the vibrating plate, so that the biomass raw material can be uniformly distributed in the reaction area of the gasification furnace, and the deviation of the raw material distribution uniformity is not more than ±15%.

[0051] In the feeding process, the appropriate amount of inert gas or air is injected into the feeding channel through the airflow auxiliary device, and the airflow speed can be adjusted between 1 meter / second and 10 meters / second. The proportional relationship between the airflow flow rate Q of the airflow auxiliary device and the feeding amount M is determined through experiments, and the adjustment range of the proportional coefficient is between 0.1 and 1. According to the characteristics of different biomass raw materials, the optimal feeding uniformity effect is achieved, and the dispersion and uniform distribution of the raw materials are further promoted, and the gasification reaction efficiency is improved.

[0052] S4, raw material pretreatment optimization step: the screened biomass raw material is crushed, the particle size of the crushed raw material meets the reaction requirements of the gasifier, a jaw crusher or a hammer crusher is used, and the crushing ratio of the crusher is adjustable between 5 and 20. According to the characteristics of different raw materials, the appropriate crushing ratio is selected, and the uniformity of the particle size of the crushed raw material is not less than 80%.

[0053] The crushed raw material is dried, the drying temperature is adjustable between 50°C and 150°C, the drying time is determined according to the moisture content and the feeding amount of the raw material, the drying is carried out through a hot air circulation system, the hot air flow rate is calculated according to the volume and moisture content of the raw material, and the calculation formula is , wherein V is the hot air flow rate, m is the mass of the raw material, H1 is the initial moisture content of the raw material, H2 is the target moisture content, C is the specific heat capacity of air, T1 is the initial temperature of the hot air, and T2 is the exhaust temperature of the hot air. The moisture content of the raw material is reduced to the optimal reaction moisture content range of the gasifier, and the gasification efficiency is improved.

[0054] S5, energy recovery and utilization step: during the operation of the gasifier, the heat in the high-temperature flue gas is recovered through a heat exchanger, and the heat exchange efficiency is not less than 70%. Part of the recovered heat is used to preheat the air or inert gas entering the gasifier, and the preheating temperature can be increased to 100°C-300°C. The calculation formula is , wherein T p is the temperature of the preheated gas, T i is the initial gas temperature, Q r is the recovered heat, m a is the gas mass flow rate, and C a is the specific heat capacity of the gas. The other part is used to drive the power generation device to generate electricity, and the power generation efficiency is between 10% and 30%. The generated power can be supplied to the motors and other equipment in the feeding system, reducing the overall energy consumption of the system.

[0055] S6, emission monitoring and regulation step: real-time monitoring of the emissions of the gasifier, including carbon monoxide, carbon dioxide, particulate matter, etc., using high-precision gas sensors and particulate matter sensors, carbon monoxide detection accuracy is ±5ppm, carbon dioxide detection accuracy is ±20ppm, particulate matter detection accuracy is ±1mg / m³. When the concentration of emissions exceeds the environmental protection standard, adjust the operating parameters of the gasifier, such as temperature, feed amount, air supply, etc. for regulation. Let the carbon monoxide concentration adjustment coefficient be β, the carbon dioxide concentration adjustment coefficient be γ, and the particulate matter concentration adjustment coefficient be ε. Determine the adjustment coefficient according to the over-standard concentration of emissions, and calculate the adjustment amplitude of the feed amount by changing the adjustment amplitude of the feed amount as , where △M is the adjustment amplitude of the feed amount, M0 is the initial feed amount, C CO is the over-standard concentration of carbon monoxide, C CO2 is the over-standard concentration of carbon dioxide, and C PM is the over-standard concentration of particulate matter, to ensure that the emissions meet environmental protection requirements.

[0056] S7, fault detection and early warning step: real-time monitoring of the working state of key components of the feeding system, such as sensors, motors, feeders, etc. Monitor the motor working current through the current sensor, the monitoring accuracy is ±0.1 ampere, the temperature sensor monitors the temperature of the key parts, the accuracy is ±2℃, when abnormal conditions are detected, such as excessive current, high temperature, abnormal sensor signal, etc., immediately send a fault warning signal.

[0057] The fault warning signal is sent to the operator through various ways such as audible and visual alarm, short message notification or system pop-up window, and the sending time is not more than 1 minute, so as to take timely maintenance measures to ensure the stable operation of the system. It also has a fault self-diagnosis function. When the fault warning signal is sent, the deviation of working current I and normal current I0 exceeds β, β=0.2I0, the deviation of temperature T and normal working temperature T0 exceeds γ, γ=5℃, the system automatically diagnoses the fault reason, the diagnosis accuracy is not less than 80%, and provides corresponding maintenance suggestions, the effective rate of maintenance suggestions is not less than 70%.

[0058] In the present application, in the raw material detection and screening step, the humidity sensor uses a capacitive humidity sensor, the relationship between the capacitance change and the humidity is determined by a specific calibration curve, the fitting degree of the calibration curve is not less than 98%, to improve the accuracy of humidity detection.

[0059] In the present application, in the feed amount calculation and control step, the intelligent algorithm uses a combination of neural network algorithm and fuzzy control algorithm, the neural network algorithm learns and predicts the running data of the gasifier, the fuzzy control algorithm accurately controls the feed amount according to the prediction result, making the control effect more stable and accurate, and the system response time is shortened by not less than 20%.

[0060] In the present application, in the step of guaranteeing the uniformity of feeding, the proportional relationship between the airflow flow rate of the airflow auxiliary device and the feeding amount is determined through experiments, and the adjustment range of the proportional coefficient is between 0.1 and 1, which is flexibly adjusted according to the characteristics of different biomass raw materials, so as to achieve the best feeding uniformity effect.

[0061] In the present application, in the step of energy recovery and utilization, the heat exchanger adopts a high-efficiency finned heat exchanger, the fin structure of which is optimized and designed to increase the heat exchange area, and the calculation formula is S=n×l×w×cosθ, wherein S is the heat exchange area, n is the number of fins, l is the fin length, w is the fin width, and cosθ is the included angle between the fin and the airflow direction, thereby improving the heat exchange efficiency, and the material of the heat exchanger is selected to be an alloy material resistant to high temperature and corrosion, thereby prolonging the service life.

[0062] The present application also discloses a biomass gasification furnace automatic feeding system, which comprises:

[0063] The raw material detection and screening device comprises a humidity sensor, a metal detector, a size screening device and a temporary storage bin, and is used for detecting, screening and temporarily storing the biomass raw material, and the components work cooperatively to ensure that the raw material entering the feeding system is qualified in quality and stable in supply.

[0064] The feeding amount calculation control unit is composed of a data acquisition module, an intelligent algorithm module and a control execution module, the data acquisition module acquires the operation parameters of the gasification furnace, the intelligent algorithm module calculates the feeding amount according to the operation parameters, and the control execution module controls the operation of the feeding device to realize precise control of the feeding amount.

[0065] The feeding uniformity guarantee mechanism is provided with a spiral feeder or a vibrating feeder and an airflow auxiliary device, and the uniform distribution of the biomass raw material in the gasification furnace is guaranteed through the specially designed structure of the feeder and the airflow assistance.

[0066] The raw material pretreatment optimization module comprises a jaw crusher or a hammer crusher and a hot air circulating drying system, and is used for crushing and drying the biomass raw material, so that the particle size and humidity of the raw material meet the reaction requirements of the gasification furnace.

[0067] The energy recovery and utilization module is composed of a heat exchanger, a preheating pipeline and a power generation device, the heat exchanger recovers the high-temperature flue gas heat of the gasification furnace, the preheating pipeline transfers the heat to the air or inert gas entering the gasification furnace, and the power generation device generates electricity by utilizing the recovered heat and supplies the system equipment.

[0068] The emission monitoring and regulation module is equipped with high-precision gas sensors and particulate matter sensors, and is used for monitoring the concentration of the emissions of the gasification furnace, and when the concentration exceeds the standard, the operation parameters of the gasification furnace are adjusted for regulation, so as to ensure that the emissions meet the environmental protection requirements.

[0069] The fault detection and early warning module is connected to the key components of the feeding system, monitors the working state in real time, sends an early warning signal in time when a fault occurs, and can perform preliminary fault diagnosis, thereby maintaining the normal operation of the system.

[0070] In the application, the metal detector in the raw material detection and screening device adopts an electromagnetic induction type metal detector, the working frequency of which is adjustable between 5 kHz and 100 kHz, and can effectively detect different types of metal impurities, and the detection depth of common metals such as iron, copper and aluminum is not less than 5 cm.

[0071] In the application, the data acquisition module in the feeding amount calculation control unit adopts a high-precision sensor, the data acquisition frequency of the sensor is adjustable between 1 Hz and 10 Hz, and the running parameters of the gasification furnace can be accurately obtained in real time, thereby providing a reliable basis for the calculation of the feeding amount.

[0072] The above is only a preferred specific embodiment of the application, but the protection scope of the application is not limited thereto, any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the application within the technical range disclosed by the application, which should be covered within the protection scope of the application.

Claims

1. A biomass gasifier automatic feeding method, characterized in that: The following steps are involved: S1. Raw material detection and screening step: Utilize multiple sensors to detect the biomass raw materials, including a humidity sensor to detect the raw material humidity, a capacitive humidity sensor, a metal detector to detect metal impurities in the raw materials, an electromagnetic induction metal detector, and a size screening device to screen out raw materials that meet the gasifier feed port size requirements; The temporary storage silo has a material level monitoring function, using an ultrasonic material level meter or a radar material level meter. When the material level falls below the set lower limit, a raw material replenishment signal is triggered; S2. Feed rate calculation and control steps: Based on the real-time operating parameters of the gasifier, the required biomass feed rate is calculated using a built-in intelligent algorithm. This algorithm is based on a gasifier operation model established through big data analysis. The intelligent algorithm combines a neural network algorithm with a fuzzy control algorithm. The learning rate of the neural network algorithm is set to η, with an initial value of 0.

01. During the training process, it is adjusted according to the change of the loss function L. When the decrease in L after k consecutive iterations is less than δ, k=5, δ=0.01, η=η×0.

5. The control rules of the fuzzy control algorithm are determined based on expert experience and experimental data. Control the motor speed or delivery frequency of the feeding device to accurately adjust the feeding amount and achieve an accurate match between the feeding amount and the operating requirements of the gasifier; S3. Feeding uniformity assurance step: Use a screw feeder or a vibrating feeder for feeding. The internal structure of the feeder is designed, specifically: the pitch gradient of the spiral blade or the amplitude adjustment function of the vibrating plate, so that the biomass raw materials are evenly distributed in the reaction area of ​​the gasifier; During the feeding process, an appropriate amount of inert gas or air is injected into the feeding channel through the airflow assist device. The proportional relationship between the airflow rate Q of the airflow assist device and the feeding amount M is determined by experiments, and the adjustment range of the proportional coefficient is between 0.1 and 1; S4. Raw material pretreatment optimization step: The screened biomass raw materials are crushed to a particle size that meets the reaction requirements of the gasifier. A jaw crusher or hammer crusher is used, and the crushing ratio of the crusher is adjustable between 5 and 20. The crushed raw materials are dried through a hot air circulation system. The hot air flow rate is calculated based on the volume and humidity of the raw materials. The calculation formula is: , where V is the hot air flow rate, m is the raw material mass, H1 is the initial humidity of the raw material, H2 is the target humidity, C is the specific heat capacity of air, T1 is the initial temperature of the hot air, and T2 is the hot air exhaust temperature; S5. Energy recovery and utilization steps: During the operation of the gasifier, the heat in the high-temperature flue gas is recovered through the heat exchanger. Part of the recovered heat is used to preheat the air or inert gas entering the gasifier. The preheating temperature can be raised to 100℃-300℃. The calculation formula is: , where T p is the gas temperature after preheating, T i is the initial gas temperature, Q r To recover heat, m a is the gas mass flow rate, C a The specific heat capacity of the gas is 1%, and the other part is used to drive the power generation device to generate electricity. The power generation efficiency is between 10% and 30%. The generated electricity can be supplied to the motor in the feeding system. S6. Emission monitoring and control steps: Real-time monitoring of gasifier emissions, including carbon monoxide, carbon dioxide, and particulate matter, using high-precision gas sensors and particulate matter sensors. When the emission concentration exceeds the environmental protection standard, the gasifier operating parameters are adjusted to control the emission. The carbon monoxide concentration adjustment coefficient is set to β, the carbon dioxide concentration adjustment coefficient is set to γ, and the particulate matter concentration adjustment coefficient is set to ε. The size of each adjustment coefficient is determined according to the emission concentration exceeding the standard. The adjustment range is calculated by changing the feed rate: , where △M is the adjustment range of feeding amount, M0 is the initial feeding amount, C CO is the excess concentration of carbon monoxide, C CO2 is the excess concentration of carbon dioxide, C PM is the concentration of particulate matter exceeding the standard; S7, Fault detection and early warning step: Real-time monitoring of key components of the feeding system, monitoring of motor operating current through current sensors, and monitoring of key parts temperature through temperature sensors. When an abnormality is detected, a fault early warning signal is immediately issued; The fault warning signal is sent to the operator through an audible and visual alarm, SMS notification or system pop-up window. It also has a fault self-diagnosis function. When the fault warning signal is issued, if the working current I deviates from the normal current I0 by more than β, β=0.2I0, or the temperature T deviates from the normal working temperature T0 by more than γ, γ=5℃, the system will automatically make a preliminary diagnosis of the cause of the fault and provide corresponding maintenance suggestions.

2. The automatic feeding method for a biomass gasifier according to claim 1, characterized in that: In the raw material detection and screening steps, the humidity sensor uses a capacitive humidity sensor, and the relationship between its capacitance change and humidity is determined by a calibration curve, and the fitting degree of the calibration curve is not less than 98%.

3. The automatic feeding method for a biomass gasifier according to claim 1, characterized in that: In the feed rate calculation and control steps, the intelligent algorithm adopts a combination of neural network algorithm and fuzzy control algorithm. The neural network algorithm learns and predicts the gasifier operation data, and the fuzzy control algorithm accurately controls the feed rate based on the prediction results.

4. The automatic feeding method for a biomass gasifier according to claim 1, characterized in that: In the step of ensuring feeding uniformity, the proportional relationship between the airflow rate of the airflow assist device and the feeding amount is determined through experiments. The adjustment range of the proportional coefficient is between 0.1 and 1, and it can be flexibly adjusted according to the different characteristics of the biomass raw materials.

5. The automatic feeding method for a biomass gasifier according to claim 1, characterized in that: In the energy recovery and utilization step, the heat exchanger adopts a high-efficiency fin-type heat exchanger. Its fin structure has been optimized to increase the heat exchange area. The calculation formula is S=n×l×w×cosθ, where S is the heat exchange area, n is the number of fins, l is the fin length, w is the fin width, and cosθ is the angle between the fin and the airflow direction. The material of the heat exchanger is a high-temperature resistant and corrosion-resistant alloy material.

6. An automatic feeding system for a biomass gasifier according to any one of claims 1 to 5, characterized in that: include: Raw material detection and screening device, including a humidity sensor, metal detector, size screening device and temporary storage silo, is used to detect, screen and temporarily store biomass raw materials, and each component works together; The feed rate calculation control unit is composed of a data acquisition module, an intelligent algorithm module, and a control execution module. The data acquisition module collects the gasifier operating parameters, the intelligent algorithm module calculates the feed rate based on the operating parameters, and the control execution module controls the operation of the feeding device. Feeding uniformity guarantee mechanism, equipped with a spiral feeder or vibrating feeder and an airflow assist device, which ensures the uniform distribution of biomass raw materials in the gasifier through the feeder and airflow assistance; Raw material pretreatment optimization module, including a jaw crusher or hammer crusher and a hot air circulation drying system, is used to crush and dry the biomass raw materials so that the particle size and moisture content meet the reaction requirements of the gasifier; The energy recovery module consists of a heat exchanger, a preheating pipe, and a power generation device. The heat exchanger recovers heat from the high-temperature flue gas in the gasifier. The preheating pipe transfers heat to the air or inert gas entering the gasifier. The power generation device uses the recovered heat to generate electricity and supply it to system equipment. The emission monitoring and control module is equipped with high-precision gas sensors and particulate matter sensors to monitor the emission concentration of the gasifier. When the concentration exceeds the standard, the gasifier operating parameters are adjusted to ensure that the emission meets environmental protection requirements. The fault detection and early warning module is connected to the key components of the feeding system, monitors its working status in real time, issues early warning signals in time when a fault occurs, and can perform preliminary fault diagnosis.

7. The automatic feeding system for biomass gasifier according to claim 6, characterized in that: The metal detector in the raw material detection and screening device adopts an electromagnetic induction metal detector, whose operating frequency is adjusted between 5 kHz and 100 kHz to detect different types of metal impurities. The detection depth of iron, copper and aluminum is not less than 5 cm.

8. The automatic feeding system for biomass gasifier according to claim 6, characterized in that: The data acquisition module in the feed rate calculation control unit uses a high-precision sensor. The data acquisition frequency of the sensor is adjusted between 1 Hz and 10 Hz to obtain the gasifier operating parameters in real time and accurately.

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