Control method of high-efficiency biomass gasifier system

Abstract

The invention relates to the technical field of biomass gasification control, in particular to a high-efficiency control method of a biomass gasifier system, which comprises the following steps: constructing a double-layer PID control ring of the biomass gasifier system, the double-layer PID control ring comprising an upper-layer control ring and a lower-layer control ring; the feeding amount of the gasifier is adaptively adjusted based on the upper-layer control ring; and the air volume of the gasifier blower is adaptively adjusted based on the lower-layer control ring. The temperature of the upper layer and the lower layer in the furnace body can be controlled in a partitioned manner, so that the temperature in the gasification furnace is in an optimal gasification state, and the gas production stability and the gasification efficiency of the gasification furnace are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of biomass gasification control, and more particularly to a control method for a high-efficiency biomass gasification furnace system. Background Art

[0002] At present, the biomass gasification process has low gasification efficiency due to the variability of raw material characteristics (including differences in moisture content, particle size, type, dust content, etc.) and gasification reaction conditions (temperature, pressure, flow rate, air intake, and air output). Traditional control methods often cannot adapt to these changes in time when gas production is low, resulting in unstable gas quality, a large amount of tar and other impurities, affecting subsequent utilization, and serious energy waste.

[0003] Therefore, how to improve gas production stability and gasification efficiency is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0004] In view of this, the present invention provides a control method for a high-efficiency biomass gasifier system, which can improve the gas production stability of the gasifier and improve the gasification efficiency.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A control method for a high-efficiency biomass gasifier system, comprising:

[0007] Constructing a double-level PID control loop for a biomass gasifier system, wherein the double-level PID control loop includes an upper control loop and a lower control loop;

[0008] Adaptively adjusting the feed amount of the gasifier based on the upper control loop;

[0009] The air volume of the gasifier blower is adaptively adjusted based on the lower control loop.

[0010] Furthermore, the biomass gasification furnace system includes: a first loader, a second loader, a buffer silo, a tower grate, a gasification furnace blower and a gas induced draft fan; a plurality of temperature transmitters are installed from top to bottom inside the gasification furnace; level meters are installed in the buffer silo and on the top of the gasification furnace;

[0011] The first loader is used to lift the material in the silo into the buffer silo;

[0012] The second loader is used to drive the material in the buffer silo into the gasifier;

[0013] The gasifier blower is used to provide oxygen for the reaction in the gasifier, and a blower flow meter is installed on the pipeline between the gasifier blower and the gasifier;

[0014] The gas induced draft fan is used to extract the gas in the gasifier.

[0015] Further, the upper control loop includes a first upper main regulator and an upper sub regulator;

[0016] The first upper layer main regulator performs PID calculation according to the target value of the upper layer control temperature of the gasifier and the actual temperature value collected by the upper layer temperature sensor in the gasifier to obtain the result a;

[0017] The upper auxiliary regulator performs the following calculation based on the result a and the correction coefficient x: a*x, converts the calculation result into a height control value of the material, and controls the action of the feed motor according to the height control value;

[0018] If the actual temperature value collected by the upper temperature transmitter in the gasifier is less than the target value of the upper control temperature, the result a calculated by the first upper main regulator decreases, and the height control value also decreases accordingly. At this time, the upper auxiliary regulator controls the feed motor to reduce the feed speed;

[0019] If the actual temperature value collected by the upper temperature transmitter in the gasifier is greater than the target value of the upper control temperature, the calculation result a of the first upper main regulator increases, and the height control value also increases accordingly. At this time, the upper auxiliary regulator controls the feed motor to increase the feed speed.

[0020] Furthermore, the material height in the gasifier is fed back to the upper sub-regulator in real time, and the material height in the gasifier is maintained between 7.1 meters and 9.3 meters by controlling the action of the feed motor. Within this material height range, the upper layer temperature of the gasifier is maintained between 100°C and 160°C.

[0021] Furthermore, the upper control loop further includes a second upper main regulator; the second upper main regulator controls the execution action of the induced draft fan of the gasifier according to the target pressure value of the upper layer of the gasifier and the measured pressure value of the upper layer of the gasifier;

[0022] When the pressure target value is greater than the pressure measurement value, the second upper main regulator controls the gasifier induced draft fan to increase the speed;

[0023] When the pressure target value is less than the pressure measurement value, the second upper main regulator controls the gasifier induced draft fan to reduce the rotation speed.

[0024] Further, the lower control loop includes a lower main regulator and a lower sub regulator;

[0025] The lower layer main regulator performs PID calculation according to the target value of the lower layer control temperature of the gasifier and the actual temperature value collected by the lower layer temperature sensor in the gasifier to obtain the result A;

[0026] The lower layer sub-regulator performs the following calculation based on the result A, the lower layer pressure value B in the gasifier and the coefficient X: (AB)*X, converts the calculation result into an air volume control value, and controls the action of the gasifier blower according to the air volume control value;

[0027] If the actual temperature value collected by the lower temperature sensor in the gasifier is less than the target value of the lower control temperature, the result A of the lower main regulator operation increases, and the air volume control value also increases accordingly. At this time, the lower auxiliary regulator controls the gasifier blower to increase the air volume;

[0028] If the actual temperature value collected by the lower temperature sensor in the gasifier is greater than the target value of the lower control temperature, the result A of the lower main regulator operation decreases, and the air volume control value also decreases accordingly. At this time, the lower sub-regulator controls the gasifier blower to reduce the air volume.

[0029] Furthermore, the air volume of the gasifier blower is fed back to the lower sub-regulator in real time, and the air volume of the gasifier blower is maintained at 1000m 3 / h-5000m 3 / h range, within this air supply volume range, the temperature of the lower layer of the gasifier is maintained between 1020℃-1280℃.

[0030] Furthermore, the amount of induced air of the gasifier blower controls the consumption of materials, and its expression is:

[0031] Material consumption D = amount of air entering the furnace AFR / (theoretical amount of air for complete combustion of designed raw materials V0*air equivalent ratio ε).

[0032] It can be seen from the above technical solution that compared with the prior art, the present invention has the following beneficial effects:

[0033] The present invention regulates the gas production process of the gasifier through a double-level PID control loop, so that the temperatures of the upper and lower layers in the furnace body can be controlled in a zoned manner, and the upper pressure of the gasifier is controlled at the same time, thereby achieving more refined and higher-precision control of the gasifier, so that the temperature in the updraft gasifier is in the optimal gasification state, and the thickness of the material layer and the temperature in the upper furnace can be adjusted to effectively remove a large amount of tar, thereby improving the gas production stability of the biomass gasifier system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0035] Figure 1 A schematic diagram of the structure of the biomass gasification furnace system provided by the present invention;

[0036] Figure 2 This is a structural principle diagram of the double-level PID control loop provided by the present invention. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] The embodiment of the present invention discloses a control method for a high-efficiency biomass gasification furnace system, which is applied in the biomass gasification furnace system to solve the problem of uncoordinated individual control of parameters such as temperature, pressure, and blower flow of the biomass gasification furnace system. This control method uses a multivariable coupling control strategy, which mainly solves the problem that the temperature in the furnace cannot be controlled in different areas during single control, resulting in a large amount of tar in the gas, and aims to accurately control the gasification effect and reduce the tar content in the fuel gas.

[0039] The structure of the biomass gasifier system is as follows: Figure 1 As shown, it specifically includes: a first loader M01, a second loader M02, a buffer silo, a tower grate M03, a gasifier blower M4 and a gas induced draft fan M5; a plurality of temperature transmitters T01, T02, T03, T04, T05 are installed from top to bottom inside the gasifier; a level meter L01 is installed on the top of the gasifier; an upper level meter L2 and a lower level meter L3 are respectively installed in the buffer silo; the gasifier blower M4 is connected to the gasifier through a pipeline, and an electric control valve and a blower flow meter F01 are installed on the pipeline; a pressure transmitter P01 is installed on the lower layer of the gasifier; the gas layer of the gasifier is connected to the input end of the gas induced draft fan M5 through a gas pipeline, and the output end of the gas induced draft fan M5 is connected to the gas-consuming equipment through the gas pipeline, and an electric control valve is installed on the gas pipeline between the gas layer of the gasifier and the input end of the gas induced draft fan M5.

[0040] The gasifier is divided into a gas layer, a drying layer, a pyrolysis layer, a reduction layer and an oxidation layer from top to bottom;

[0041] The core area temperature of the drying layer is 100-150℃, the material is dehydrated and dried, most of the water is precipitated below 105℃, and then the temperature rises rapidly.

[0042] The core zone temperature of the pyrolysis layer is 300-700℃, and the high molecular organic matter begins an endothermic irreversible thermal decomposition reaction. The higher the temperature, the more intense the reaction. The products are a complex mixed gas and solid carbon. The mixed gas includes at least hundreds of hydrocarbons, some of which can be condensed into tar at room temperature.

[0043] The reduction layer mainly undergoes endothermic reactions, with the core temperature at 700-900°C. The chemical reaction formula is: C+CO2=2CO, C+H2O(g)=CO+H 2 ,C+H2O(g)=CO2+2H 2 ,C+2H 2 =CH4, CO+H2O(g)=CO2+H2.

[0044] The oxide layer undergoes an exothermic reaction, with the core temperature at 1000-1350°C. The chemical reaction formula is: CO+O2=CO 2， 2CO+O2=CO2.

[0045] The temperature transmitter T01 feeds back the temperature of the oxidation layer, the temperature transmitter T02 feeds back the temperature of the reduction layer, the temperature transmitter T03 feeds back the temperature of the pyrolysis layer, the temperature transmitter T04 feeds back the temperature of the drying layer, and the temperature transmitter T05 feeds back the temperature of the gas layer.

[0046] The gasifier blower M4 is a variable frequency blower, which is used to provide sufficient O2 for the reaction in the gasifier. The blower flowmeter F01 feeds back the flow rate of O2, and the biomass furnace lower layer pressure transmitter P01 feeds back the blower's blower pressure.

[0047] The upper level meter L2 and the lower level meter L3 feedback the material level of the buffer silo.

[0048] The first loader M01 adopts a lifting loader, which is used to lift the materials in the silo into the buffer silo, and the second loader M02 adopts an auger feeder, which is used to drive the materials in the buffer silo to feed into the gasifier.

[0049] The gasifier induced draft fan M5 extracts the fuel gas and transports it to the gas-consuming equipment.

[0050] The tower grate M03 discharges the carbon slag after the oxide layer is burned out of the furnace body.

[0051] The present invention uses a double-level PID control to control the temperature of the upper and lower layers in the furnace. The specific method is:

[0052] How to build a biomass gasifier system Figure 2The double-level PID control loop shown includes an upper control loop and a lower control loop;

[0053] Adaptively adjust the feed rate of the gasifier based on the upper control loop;

[0054] The air volume of the gasifier blower is adaptively adjusted based on the lower control loop.

[0055] The two control loops mentioned above are described in detail below.

[0056] 1) The upper control loop includes a first upper main regulator and an upper sub regulator;

[0057] The height of the material in the furnace can be calculated by (3.14*R2 (radius of the gasifier)*H (height of the radar level meter)*Qm (mass of the material)) to get the weight of the material. The formula AFR (the amount of air entering the furnace) = V0 (the theoretical amount of air for complete combustion of the designed raw materials) * FCR (the amount of fuel consumed) * ε (air equivalent ratio) is used. The amount of air entering the furnace AFR (obtained by the blower air volume meter (F01)) is known. The material consumption D is calculated by the formula (D = AFR (the amount of air entering the furnace) / (V0 (the theoretical amount of air for complete combustion of the designed raw materials) * ε (air equivalent ratio)). The height of the material in the furnace can adjust the temperature of the upper layer and the tar content in the filter furnace. However, too low a temperature is not conducive to the physical and chemical reaction of the material. It is also necessary to ensure a negative pressure in the upper layer of the furnace body. The cascade PID control method of the upper layer is as follows:

[0058] The first upper main regulator performs PID calculation according to the target value of the upper control temperature of the gasifier (i.e., the upper main set value) and the actual temperature value collected by the upper temperature sensor in the gasifier (i.e., the upper main measured value), and obtains the result a;

[0059] The upper sub-regulator performs the following operation based on the result a and the correction coefficient x: a*x, converts the operation result into the height control value of the material (i.e. the upper sub-given value), compares it with the c value (i.e. the upper sub-measured value) measured by the radar level meter L01 in real time, and controls the action of the feed motor according to the height control value; at different temperature values, the operation result a has different values ​​in the CPU, and the operation results of a*x correspond to different height control values ​​respectively. During the actual operation, the corresponding height control value is directly retrieved from the pre-stored corresponding relationship according to the operation result.

[0060] If the actual temperature value collected by the upper temperature transmitter in the gasifier is less than the target value of the upper control temperature, the result a of the first upper main regulator operation decreases, and the height control value also decreases accordingly. At this time, the upper auxiliary regulator controls the feed motor to reduce the feed speed;

[0061] If the actual temperature value collected by the upper temperature transmitter in the gasifier is greater than the target value of the upper control temperature, the calculation result a of the first upper main regulator increases, and the height control value also increases accordingly. At this time, the upper sub-regulator controls the feed motor to increase the feed speed.

[0062] In the upper control loop, the material height in the gasifier (upper sub-control variable) is fed back to the upper sub-regulator in real time. The main control variable of the first upper main regulator is the upper temperature in the furnace, and the data is fed back through the T05 temperature sensor. By controlling the feeding motor, the material height in the furnace body is controlled between 7.1 meters and 9.3 meters, and the upper temperature in the furnace body is controlled between 100℃ and 160℃. The height of the material can block the heat generated by the combustion of the oxidation layer, the heat absorbed by the reaction of the reduction layer, the heat absorbed by the pyrolysis layer, and the heat absorbed by the drying layer. The higher the material height, the lower the temperature of the gas layer. While ensuring the optimal reaction temperature of the gasifier, the material height is adjusted in real time. The upper first main regulator sets the output result of the upper temperature area to be controlled as the input of the sub-regulator (converted into the material height value). The input of the sub-regulator is compared with the feedback of the radar sensor (L01). The output result of the sub-regulator controls the feeding motor to feed and adjust the material height.

[0063] In addition, the upper control loop further includes a second upper main regulator; the second upper main regulator controls the execution action of the induced draft fan of the gasifier according to the target pressure value of the upper layer of the gasifier and the measured pressure value of the upper layer of the gasifier;

[0064] When the pressure target value is greater than the pressure measurement value, the second upper main regulator controls the gasifier induced draft fan to increase the speed;

[0065] When the pressure target value is less than the pressure measurement value, the second upper main regulator controls the gasifier induced draft fan to reduce the rotation speed.

[0066] 2) The lower control loop includes a lower main regulator and a lower sub-regulator;

[0067] The height of the material in the furnace can be calculated by (3.14*R 2 (Gasifier radius) * H (Radar level meter height) * M (Material mass)) of the amount of material, FCR (Material consumption) = Q n (Output power of gasifier) / (LHV (lower heating value of material)*efficiency of gasifier) ​​to get the material consumption, and calculate the blower air volume Q (Q=AFR (air volume entering the furnace) / (V0 (theoretical air volume for complete combustion of designed raw materials)*ε (air equivalent ratio)) through the material consumption. The air intake of the gasifier shall not exceed 10% of the Q value. The size of the gasifier blower air volume not only controls the temperature of the lower oxidation reaction, but also controls the amount of O2 in the gasifier, ensuring a slight positive pressure in the lower layer of the furnace body. The cascade PID control method of the lower layer is as follows:

[0068] The lower layer main regulator performs PID calculation according to the target value of the lower layer control temperature of the gasifier (i.e., the lower layer main set value) and the actual temperature value collected by the lower layer temperature sensor in the gasifier (i.e., the lower layer main measured value), and obtains the result A;

[0069] The lower-layer sub-regulator performs the following operation based on the result A, the lower-layer pressure value B in the gasifier and the coefficient X: (AB)*X, and converts the operation result into the air volume control value (i.e., the lower-layer sub-given value). At the same time, the air volume of the gasifier blower (i.e., the lower-layer sub-measurement value) is fed back to the lower-layer sub-regulator in real time, and the action of the gasifier blower is controlled according to the air volume control value; at different temperature values, the operation result A has different values ​​in the CPU, and the lower-layer pressure value B in the gasifier also corresponds to different digital quantities. The operation results of (AB)*X correspond to different air volume control values ​​respectively. During the actual operation, the corresponding air volume control value is directly retrieved from the pre-stored corresponding relationship according to the operation result.

[0070] If the actual temperature value collected by the lower temperature sensor in the gasifier is less than the target value of the lower control temperature, the result A of the lower main regulator operation increases, and the air volume control value also increases accordingly. At this time, the lower sub-regulator controls the gasifier blower to increase the air volume; the air volume increases, the oxidation reaction becomes more intense, and the temperature increases.

[0071] If the actual temperature value collected by the lower temperature sensor in the gasifier is greater than the target value of the lower control temperature, the result A of the lower main regulator operation decreases, and the air volume control value also decreases accordingly. At this time, the lower sub-regulator controls the gasifier blower to reduce the air volume; when the air volume decreases, the oxidation reaction decreases, the temperature decreases, and the pressure value B is used as a forward feedback to adjust the fan speed to prevent the air volume from increasing or decreasing too quickly.

[0072] The main control loop of the lower control loop is used to control the temperature in the lower gasifier (i.e., the lower main control variable), and the sub-control loop is used to control the air volume of the blower in the gasifier (i.e., the lower sub-controlled variable). The sub-regulator (PID) of the lower control loop converts and compares the calculation value of the main regulator (PID) and the feedback value of the lower micro-positive pressure and air volume of the gasifier to adjust the air volume of the gasifier blower to control the lower temperature and lower micro-positive pressure of the gasifier.

[0073] The air volume of the gasifier blower is fed back to the lower-level sub-regulator in real time. By controlling the action of the gasifier blower, the micro-positive pressure in the furnace is controlled at 1KPA, and the air volume of the gasifier blower is maintained at 1000m 3 / h-5000m 3 / h, the temperature of the lower layer in the gasifier is controlled at 1020℃-1280℃, because the oxidation reaction (CO+O2=CO 2，2CO+O2=CO2) mainly reacts with O2 in the air. The greater the air volume blown in by the blower, the more intense the reaction, and the higher the heat generated (due to the nature of biomass materials, the maximum temperature is below 1400 degrees Celsius). While ensuring the optimal reaction temperature of the gasifier, the air volume and air pressure of the gasifier blower are adjusted in real time for coordinated regulation. The lower main regulator sets the output result of the temperature zone to be controlled in the lower layer as the input of the sub-regulator. The output result of the lower sub-regulator controls the air volume of the blower, and the temperature of the oxidation reaction is controlled by the size of the air volume.

[0074] Generally speaking, when the upper temperature deviation is greater than the set value, the material height in the furnace is detected and the upper cascade PID calculation is performed to control the feed auger motor to increase the feed amount to lower the temperature; when the upper temperature deviation is less than the set value, the material height in the furnace is detected and the upper cascade PID calculation is performed to reduce the feed amount of the feed auger motor to lower the temperature.

[0075] When the temperature deviation of the lower layer is greater than the set value, the pressure in the furnace and the gasifier blower flow are detected, and the lower layer cascade PID calculation is performed to reduce the blowing volume accordingly to lower the temperature; when the temperature deviation of the lower layer is less than the set value, the pressure in the furnace and the gasifier blower flow are detected, and the lower layer cascade PID calculation is performed to increase the blowing volume accordingly to increase the temperature.

[0076] The core idea of ​​the present invention is to use error to eliminate error. The difference between the target value and the actual value is obtained through PID control to obtain the input quantity, and the actual value is continuously corrected to make it closer to the target value. The advantages of double-cascade hierarchical control are fast response, small overshoot, small static error, less oscillation and low cost.

[0077] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0078] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a high-efficiency biomass gasification furnace system, characterized in that: include: Constructing a double-level PID control loop for a biomass gasifier system, wherein the double-level PID control loop includes an upper control loop and a lower control loop; Adaptively adjusting the feed amount of the gasifier based on the upper control loop; The air volume of the gasifier blower is adaptively adjusted based on the lower control loop.

2. The control method of the high-efficiency biomass gasification furnace system according to claim 1, characterized in that: The biomass gasification furnace system comprises: a first loader, a second loader, a buffer silo, a tower grate, a gasification furnace blower and a gas induced draft fan; a plurality of temperature transmitters are installed from top to bottom inside the gasification furnace; level meters are installed in the buffer silo and on the top of the gasification furnace; The first loader is used to lift the material in the silo into the buffer silo; The second loader is used to drive the material in the buffer silo into the gasifier; The gasifier blower is used to provide oxygen for the reaction in the gasifier, and a blower flow meter is installed on the pipeline between the gasifier blower and the gasifier; The gas induced draft fan is used to extract the gas in the gasifier.

3. The control method of the high-efficiency biomass gasification furnace system according to claim 1, characterized in that: The upper control loop includes a first upper main regulator and an upper sub regulator; The first upper layer main regulator performs PID calculation according to the target value of the upper layer control temperature of the gasifier and the actual temperature value collected by the upper layer temperature sensor in the gasifier to obtain the result a; The upper auxiliary regulator performs the following calculation based on the result a and the correction coefficient x: a*x, converts the calculation result into a height control value of the material, and controls the action of the feed motor according to the height control value; If the actual temperature value collected by the upper temperature transmitter in the gasifier is less than the target value of the upper control temperature, the result a calculated by the first upper main regulator decreases, and the height control value also decreases accordingly. At this time, the upper auxiliary regulator controls the feed motor to reduce the feed speed; If the actual temperature value collected by the upper temperature transmitter in the gasifier is greater than the target value of the upper control temperature, the calculation result a of the first upper main regulator increases, and the height control value also increases accordingly. At this time, the upper auxiliary regulator controls the feed motor to increase the feed speed.

4. The control method of the high-efficiency biomass gasification furnace system according to claim 3, characterized in that: The material height in the gasifier is fed back to the upper sub-regulator in real time, and the material height in the gasifier is maintained between 7.1 meters and 9.3 meters by controlling the action of the feed motor. Within this material height range, the upper temperature of the gasifier is maintained between 100°C and 160°C.

5. The control method of the high-efficiency biomass gasification furnace system according to claim 3, characterized in that: The upper control loop further includes a second upper main regulator; the second upper main regulator controls the execution action of the gasifier induced draft fan according to the target pressure value of the upper layer of the gasifier and the measured pressure value of the upper layer of the gasifier; When the pressure target value is greater than the pressure measurement value, the second upper main regulator controls the gasifier induced draft fan to increase the speed; When the pressure target value is less than the pressure measurement value, the second upper main regulator controls the gasifier induced draft fan to reduce the rotation speed.

6. The control method of the high-efficiency biomass gasification furnace system according to claim 1, characterized in that: The lower control loop includes a lower main regulator and a lower sub regulator; The lower layer main regulator performs PID calculation according to the target value of the lower layer control temperature of the gasifier and the actual temperature value collected by the lower layer temperature sensor in the gasifier to obtain the result A; The lower layer sub-regulator performs the following calculation based on the result A, the lower layer pressure value B in the gasifier and the coefficient X: (AB)*X, converts the calculation result into an air volume control value, and controls the action of the gasifier blower according to the air volume control value; If the actual temperature value collected by the lower temperature sensor in the gasifier is less than the target value of the lower control temperature, the result A of the lower main regulator operation increases, and the air volume control value also increases accordingly. At this time, the lower auxiliary regulator controls the gasifier blower to increase the air volume; If the actual temperature value collected by the lower temperature sensor in the gasifier is greater than the target value of the lower control temperature, the result A of the lower main regulator operation decreases, and the air volume control value also decreases accordingly. At this time, the lower sub-regulator controls the gasifier blower to reduce the air volume.

7. The control method of the high-efficiency biomass gasification furnace system according to claim 5, characterized in that: The air volume of the gasifier blower is fed back to the lower sub-regulator in real time, and the air volume of the gasifier blower is maintained at 1000m 3 / h-5000m 3 / h range, within this air supply volume range, the temperature of the lower layer of the gasifier is maintained between 1020℃-1280℃.

8. The control method of the high-efficiency biomass gasification furnace system according to claim 5, characterized in that: The air volume of the gasifier blower controls the material consumption, and its expression is: Material consumption D = amount of air entering the furnace AFR / (theoretical amount of air for complete combustion of designed raw materials V0*air equivalent ratio ε).

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