Self-adaptive adjustment energy-saving control system and method for biomass gasifier

Abstract

The invention discloses a self-adaptive adjustment energy-saving control system and method for a biomass gasifier. The system comprises a feeding belt conveyor, a double-screw feeder, a buffer stock bin, an auger feeder, a horn-shaped material distribution bin, the gasifier, a gasifier induced draft fan and gas utilization equipment which are connected in sequence. The method comprises the following steps: (1) a gasification furnace ignition control method; and (2) a gasification furnace stuffy furnace control method. By constructing self-adaptive adjustment of each device, the construction difficulty of an intelligent control algorithm can be reduced, the debugging difficulty of the system can be reduced, the efficiency can be improved, the safety can be guaranteed, the cost can be reduced, and the stability can be enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of biomass gasification control, and more particularly to an adaptive regulation energy-saving control system and method for a biomass gasifier. Background Art

[0002] Biomass gasification technology is a thermochemical reaction that uses oxygen or oxygen-containing substances in the air as gasifying agents to convert the combustible part of biomass fuel into combustible gas (mainly hydrogen, carbon monoxide, and methane) under high-temperature conditions, playing an active role in dealing with a large amount of crop waste, reducing environmental pollution, and improving people's living standards. With the continuous development of biomass gasification technology, the gasification efficiency and gas production quality have been gradually improved. In order to give full play to the advantages of biomass gasification technology, it is necessary to improve the control technology to increase the gas production rate, gas quality, and overall performance of the system.

[0003] A biomass gasifier is a gasifier for manufacturing straw gas (green new energy). At present, many biomass gasifiers introduce the application of intelligent algorithms such as neural networks, fuzzy control, and genetic algorithms in the control field to improve the gas production rate, gas quality, and overall performance of the system. However, intelligent algorithms have high computational resource requirements, difficult model training, real-time challenges, high requirements for data quality, difficulty in dealing with extreme situations, poor interpretability, complex maintenance, and extremely high requirements for programming and debugging personnel in system modeling and optimal control. The algorithm execution is not satisfactory during equipment debugging, and there is an energy waste phenomenon during the adjustment process using variable valve regulation.

[0004] Therefore, how to improve the control efficiency and stability of biomass gasifiers and increase the energy-saving rate is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an adaptive regulation energy-saving control system and method for a biomass gasifier to solve the deficiencies in the prior art.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A biomass gasifier adaptive regulation energy-saving control system includes a feeding belt conveyor, a double-screw feeder, a buffer bin, a screw feeder, a horn-shaped distribution bin, a gasifier, a gasifier induced draft fan, and a gas-using device connected in sequence.

[0008] In the present invention, the feeding belt conveyor and the double-screw feeder are used to lift the materials in the raw material bin into the buffer bin, the screw feeder is used to drive the materials in the buffer bin into the horn-shaped distribution bin and the interior of the gasifier, the gasifier blower and the gasifier ring fan are used to provide oxygen for the reaction in the gasifier, and the gasifier induced draft fan is used to extract the gas in the gasifier.

[0009] In the present invention, the feeding amount is controlled by a feeding belt conveyor, a double-screw feeder, and an auger feeder; the jacket water temperature is controlled by a circulating water pump of the gasifier water jacket; the air blowing amount is controlled by a gasifier blower and a gasifier annular blower; the air draft amount is controlled by a gasifier induced draft fan; slag removal is controlled by a tower grate; the equipment control of the gasifier during start-up ignition is carried out by a gasifier ignition control method; and the equipment control of the gasifier during furnace shutdown is carried out by a gasifier furnace shutdown control method.

[0010] Furthermore, high, medium, and low level gauges are installed in both the buffer bin and the trumpet-shaped distribution bin.

[0011] The beneficial effect of the above is as follows: The feeding belt conveyor and the double-screw feeder lift the material into the buffer bin. The buffer bin is equipped with high, medium, and low level gauges. After the system starts, the feeding belt conveyor and the double-screw feeder operate at a frequency of 25 Hz initially. After 10 s when there is no level signal from the high, medium, and low level gauges, the frequency of the feeding belt conveyor and the double-screw feeder is increased by 1. After the next 10 s when there is still no level signal from the high, medium, and low level gauges, the frequency of the feeding belt conveyor and the double-screw feeder is increased by 1 again, and so on. When there is a level signal at the low level of the high, medium, and low level signals, the frequency converter of the feeding belt conveyor and the double-screw feeder keeps running. When there are signals at the medium and low levels of the high, medium, and low level signals, the frequency of the frequency converter of the feeding belt conveyor and the double-screw feeder is decreased by 1. After running for another 10 s when there are signals at the medium and low levels, the frequency of the frequency converter of the feeding belt conveyor and the double-screw feeder is decreased by 1 again, and so on. When there is a level signal at the low level of the high, medium, and low level signals, the frequency converter of the feeding belt conveyor and the double-screw feeder keeps running. When there are level signals at all of the high, medium, and low level signals, the frequency converter of the feeding belt conveyor and the double-screw feeder stops running until the level gauge drops to a level where there are signals at the medium and low levels, and then the frequency converter of the feeding belt conveyor and the double-screw feeder starts running at the frequency when it stopped. The above control logic is repeated to adaptively adjust to a relatively linear frequency range for feeding to ensure linear feeding operation. The frequency conversion range of the frequency converter is limited to be adjusted between 10 - 50 Hz.

[0012] The auger feeder conveys materials into the horn-shaped distribution bin. The horn-shaped distribution bin is equipped with high, medium, and low level gauges. After the system starts, the auger feeder runs at an initial frequency of 25Hz. After 10s when there is no level signal from all the high, medium, and low level gauges, the frequency of the auger feeder inverter increases by 1. After the next 10s when there is still no signal from the high, medium, and low level gauges, the frequency of the auger feeder inverter increases by 1 again, and so on. When there is a level signal at the low level among the high, medium, and low level signals, the frequency of the auger feeder inverter keeps running. When there are signals at the medium and low levels among the high, medium, and low level signals, the frequency of the auger feeder inverter decreases by 1. After running for another 10s when there are signals at the medium and low levels, the frequency of the auger feeder inverter decreases by 1 again, and so on. When there is a level signal at the low level among the high, medium, and low level signals, the frequency of the auger feeder inverter keeps running. When there are level signals from all the high, medium, and low level gauges, the auger feeder inverter stops running until the level gauge drops to where there are signals at the medium and low levels, and then the auger feeder inverter starts running at the frequency when it stopped. Repeat the above control logic to adaptively adjust to a relatively linear frequency range for feeding to ensure linear feeding operation. The frequency conversion range of the inverter is limited to adjustment between 10 - 50Hz.

[0013] Further, the above gasifier is divided into a gas layer, a drying layer, a pyrolysis layer, a reduction layer, and an oxidation layer from top to bottom, and several temperature transmitters and pressure transmitters are installed inside the gasifier from top to bottom.

[0014] Further, temperature transmitters and pressure transmitters are installed on the gas pipeline between the input end of the above gasifier induced draft fan and the gasifier; pressure transmitters and oxygen analyzers are installed on the gas pipeline between the output end of the gasifier induced draft fan and the gas-using equipment.

[0015] The beneficial effect of the above further measures is that the gasifier induced draft fan is adaptively adjusted. Pressure transmitters and oxygen sensors are installed on the gas pipeline. After the system starts, the gasifier induced draft fan starts the inverter to run at an initial frequency of 10Hz. The gas pipeline pressure remains between 10 - 20kpa, and the oxygen sensor remains below 3%. When the oxygen sensor is greater than 3%, the frequency of the inverter remains unchanged. When the gas pipeline pressure is lower than 12kpa, the frequency of the gasifier induced draft fan increases by 1. If the gas pipeline pressure is still lower than 12kpa after 5s, the frequency of the gasifier induced draft fan inverter continues to increase by 1, and so on. When the gas pipeline pressure is in the range of 12 - 18kpa, the frequency of the induced draft fan inverter remains unchanged. When the gas pipeline pressure is higher than 18kpa, the frequency of the gasifier induced draft fan decreases by 1. If the gas pipeline pressure is still lower than 18kpa after 5s, the frequency of the gasifier induced draft fan inverter continues to decrease by 1, and so on. To prevent the lag effect on the pressure inside the gasifier caused by the frequency modulation of the induced draft fan, the gasifier blower and the gasifier ring fan follow the increase and decrease of the induced draft fan by 1. The frequency conversion range of the inverter is limited to adjustment between 10 - 50Hz.

[0016] Further, the above biomass gasifier adaptive regulation energy-saving control system further includes a tower grate, a gasifier blower, a gasifier annular blower, and a gasifier water jacket circulating water pump, all of which are connected to the gasifier respectively.

[0017] Furthermore, pressure transmitters are respectively installed on the pipelines between the above gasifier blower and the gasifier annular blower and the gasifier.

[0018] The beneficial effect of the above further measures is that the tower grate is adaptively regulated. Temperature transmitters are set in the oxidation layer and reduction layer of the gasifier. After the system starts and operates normally, the temperatures of both the oxidation layer and the reduction layer are greater than 500 °C. When the temperature difference between the oxidation layer and the reduction layer is less than 100 °C, the tower grate operates at a frequency of 30 Hz. When the temperature difference between the oxidation layer and the reduction layer is greater than 150 °C, the grate stops operating.

[0019] For the gasifier blower and the gasifier annular blower, temperature transmitters and pressure transmitters are set inside the gasifier. A pressure transmitter is set at the inlet of the gasifier blower, and a pressure transmitter is set for the gasifier annular blower. After the system starts and operates normally, the electric valve of the gasifier blower is fully open, and the gasifier blower operates at a starting frequency of 5 Hz. When the temperature value is higher than 500 °C and the pressure transmitter at the inlet of the gasifier blower is less than 6 kPa, the upper layer of the gasifier operates under a negative pressure of (-100 Pa) - (-20 kPa). When the negative pressure of the upper layer of the gasifier is less than -15 kPa, the frequency of the blower frequency converter increases by 1. If the negative pressure does not decrease after 5 s, the frequency of the gasifier blower frequency converter increases by 1, and so on. When the negative pressure of the upper layer of the gasifier is less than -20 kPa, the frequency of the gasifier blower frequency converter increases by 5. If the negative pressure is not less than -20 kPa after 5 s, the frequency of the blower frequency converter increases by 5, and so on. When the temperature value is higher than 500 °C, the pressure transmitter at the inlet of the blower is less than 6 kPa, and the upper layer of the gasifier operates under a negative pressure of (-1 kPa) - (-15 kPa), the frequency of the frequency converter remains unchanged. When the temperature value is higher than 500 °C, the pressure transmitter at the inlet of the blower is less than 6 kPa, and the upper layer of the gasifier operates under a negative pressure of (-100 Pa) - (-20 kPa), when the negative pressure of the upper layer of the gasifier is greater than -1 kPa, the frequency of the blower frequency converter decreases by 1. If the negative pressure does not increase after 5 s, the frequency of the blower frequency converter decreases by 1, and so on. When the negative pressure of the upper layer of the gasifier is greater than -500 Pa, the frequency of the blower frequency converter decreases by 5. If the negative pressure does not increase after 5 s, the frequency of the blower frequency converter decreases by 5, and so on. When the negative pressure during the operation of the gasifier blower exceeds -20 kPa or the operation frequency of the blower reaches 50 Hz, the gasifier annular blower starts to adjust the frequency in the same adjustment form as above, and the electric valve of the annular blower is fully open. When the negative pressure is greater than -100 Pa, the gasifier annular blower stops operating and closes the electric valve. The frequency conversion range of the frequency converter is limited to be adjusted between 5 Hz and 50 Hz.

[0020] The circulating water pump of the gasifier water jacket is equipped with a jacket water thermometer in the gasifier water jacket. After the system starts, the frequency converter of the circulating water pump runs at an initial frequency of 20 Hz, and the temperature of the jacket water is monitored in real time. When the water temperature is below 80°C, the frequency converter does not adjust and runs at the initial frequency. When the temperature is above 90°C, the operating frequency of the frequency converter increases by 1. If the temperature does not drop to between 80°C and 90°C after the next 10 s, the operating frequency of the frequency converter increases by 1, and so on. When the jacket water temperature is between 80°C and 90°C, the frequency remains unchanged. When the liquid level is low, the system is not allowed to start. When the liquid level is low during operation, the system enters the furnace-smothering state and repeats the above control logic to adaptively adjust to a frequency range where the jacket water temperature is relatively linear to ensure linear temperature operation. The frequency conversion range of the frequency converter is limited to adjustment between 20 Hz and 50 Hz.

[0021] A self-adaptive adjustment and energy-saving control method for a biomass gasifier uses the above-mentioned self-adaptive adjustment and energy-saving control system for a biomass gasifier, and specifically includes the following steps:

[0022] (1) Gasifier ignition control method

[0023] During gasifier ignition control, the feeding program executes the feeding belt, double-screw feeder, auger feeder conveying, and the operating program of the circulating water pump of the gasifier water jacket. The gasifier blower runs, the gasifier annular blower runs, and the electric valves are fully open. The gasifier induced draft fan does not start. The electric valve of the gas pipeline is closed, the pneumatic valve is closed, and the exhaust valve is fully open. When the temperature of the oxidation layer in the gasifier is greater than 500°C and there is a slight positive pressure in the upper layer of the gasifier, the ignition gun ignites. After successful ignition, the exhaust valve is closed, the gas pipeline valve is opened, and the furnace induced draft fan is started to enter the normal operation program;

[0024] (2) Gasifier furnace-smothering control method

[0025] During gasifier furnace-smothering control, the feeding program executes the feeding belt, double-screw feeder, auger feeder conveying, the operation of the circulating water pump of the gasifier, and the operation program of the tower grate. The gasifier blower runs, the gasifier annular blower stops, and the electric valves are closed. The gasifier induced draft fan does not start. The electric valve of the gas pipeline is closed, the pneumatic valve is closed, and the exhaust valve is fully open. When the temperature of the oxidation layer in the gasifier is greater than 500°C and there is a slight positive pressure in the upper layer of the gasifier, the ignition gun ignites. After successful ignition, the temperature of the oxidation layer in the gasifier is maintained not lower than 500°C.

[0026] Further, in the above step (1), the operating frequency of the gasifier blower is 5 Hz; the ignition gun ignites once every 60 s until ignition is successful.

[0027] Further, in the above step (2), the operating frequency of the gasifier blower is 5 Hz; the ignition gun ignites once every 60 s until ignition is successful.

[0028] Further, in the above step (2), when the temperature of the oxidation layer in the gasifier is lower than 500°C, the frequency of the gasifier blower inverter increases by 1 every 10 s; when the temperature of the oxidation layer in the gasifier exceeds 500°C, it operates at the lowest frequency until the system switches to normal production.

[0029] As can be seen from the above technical solutions, compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] The control system of the present invention has a simple structure and is easy to understand, and can effectively solve the problems faced by biomass gasifier control engineers in the actual implementation process, such as simple control being unable to achieve automatic adjustment, complex control being obscure and difficult to understand, and the structure being complex with a long debugging period.

[0031] The control method of the present invention applies variable frequency regulation to motors, water pumps, and fans. Compared with regulating the flow rate of pumps and fans by changing the valve opening in variable valve regulation, the power of the pump or fan remains basically unchanged in variable valve regulation, the performance curve of the pump or fan remains unchanged, and the resistance characteristic curve of the pipeline changes. However, variable frequency regulation works by changing the performance curve of the pump and fan, and there is no additional resistance during speed change, achieving an ideal energy-saving effect for the system.

[0032] The control system of the present invention is applied in the biomass gasifier system to solve problems such as high computing resource requirements for intelligent algorithms in the biomass gasifier system, difficult model training, high requirements for data quality, difficulty in handling extreme situations, complex maintenance, high requirements for programming and debugging personnel in system modeling and optimal control, and unsatisfactory algorithm execution during equipment debugging. The control method of the present invention adaptively adjusts the induced draft fan, blower, annular fan, water jacket circulation pump, feeding belt conveyor, double screw feeder, auger feeder, and tower grate of the gasifier according to the changes in the gas side usage and the feedback of sensors, and finally realizes the adaptive adjustment of the gasifier with the change of the usage on the gas consumption side. The control structure is simple, easy for system programming and debugging, and saves development time.

[0033] By constructing the adaptive adjustment of each device, the present invention can reduce the construction difficulty of intelligent control algorithms, reduce the debugging difficulty of the system, improve efficiency, ensure safety, reduce costs, and enhance stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic structural diagram of the biomass gasifier adaptive adjustment energy-saving control system in Embodiment 1;

[0035] Figure 2 It is a schematic flow diagram of the biomass gasifier adaptive adjustment energy-saving control method in Embodiment 2;

[0036] Figure 3 It is a schematic flow diagram of the gasifier ignition control method in Embodiment 2;

[0037] Figure 4 It is a schematic flow diagram of the furnace shutdown control method for the gasifier in Embodiment 2. Specific embodiments

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0039] Embodiment 1

[0040] The biomass gasifier adaptive adjustment energy-saving control system, as Figure 1 shown, specifically includes: double-screw feeder M1, feeding belt conveyor M2, buffer bin, buffer bin level gauges LT04 / LT05 / LT06, auger feeder M3, flared distribution bin, flared distribution bin level gauges LT01 / LT02 / LT03, tower grate M4, gasifier blower M5, gasifier ring blower M6, gasifier induced draft fan M7, gasifier water jacket circulating water pumps M9 / M10; multiple temperature transmitters TT01, TT02, TT03, TT04 are installed from bottom to top inside the gasifier; water jacket temperature transmitter TT06; water jacket level transmitter LT11; soft water tank level transmitter LT12; the gasifier blower M4 is connected to the gasifier through a pipeline, and an electric control valve SV1 and a pressure transmitter PT01 are installed on the pipeline; the gasifier ring blower M5 is connected to the gasifier through a pipeline, and an electric control valve SV2 and a pressure transmitter PT02 are installed on the pipeline; a pressure transmitter PT03 is installed on the upper layer of the gasifier; the gas layer of the gasifier is connected to the input end of the gasifier induced draft fan M7 through a gas pipeline with a pressure transmitter PT04 and a temperature transmitter TT05, and the output end of the gasifier induced draft fan M7 is connected to the gas-using equipment through a gas pipeline. An electric control valve SV3, a pressure transmitter PT05, an oxygen analyzer AI01, and pneumatic valves SV12 / SV13 are installed on the gas pipeline between the gas layer of the gasifier and the input end of the gasifier induced draft fan M7.

[0041] 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;

[0042] Among them, the core area temperature of the drying layer is 80 - 150 °C, the material is dehydrated and dried, most of the water is precipitated below 105 °C, and then the temperature rises rapidly.

[0043] The temperature in the core area of the pyrolysis layer is 300 - 500 °C. The high-molecular organic substances start the irreversible thermal decomposition reaction by absorbing heat. The higher the temperature, the more intense the reaction. The products are complex mixed gases and solid carbon. The mixed gases include at least hundreds of hydrocarbons, and some can be condensed into tar at room temperature.

[0044] The reduction layer mainly undergoes endothermic reactions. The temperature in the core area is 600 - 800 °C. The chemical reaction equations are: C + CO 2 = 2CO, C + H 2 O(g) = CO + H 2 ,C + H 2 O(g) = CO 2 + 2H 2 ,C + 2H 2 = CH 4 ,CO + H 2 O(g) = CO 2 + H 2 。

[0045] The oxidation layer undergoes exothermic reactions. The temperature in the core area is 900 - 1350 °C. The chemical reaction equations are: CO + O 2 = CO 2 ,2CO + O 2 = CO 2 。

[0046] The temperature transmitters TT01 and TT02 feedback the temperature of the oxidation layer, the temperature transmitter TT03 feedbacks the temperature of the reduction layer, the temperature transmitter TT04 feedbacks the temperature of the gas layer, the temperature transmitter TT05 feedbacks the temperature of the gas pipeline, and the temperature transmitter TT06 feedbacks the temperature of the water jacket of the gasifier.

[0047] The gasifier blower and the gasifier annular blower M5 / M6 are variable-frequency blowers, which are used to provide sufficient O 2 for the reactions inside the gasifier. The pressure transmitters PT01 and PT02 on the air inlet pipelines of the gasifier blower and the gasifier annular blower M5 / M6 feedback the air blowing pressure of the blower, and the pressure transmitter PT03 feedbacks the pressure of the gas layer.

[0048] The level gauges L04 / L05 / L06 feedback the material level of the buffer silo.

[0049] The level gauges L01 / L02 / L03 feedback the material level of the buffer silo.

[0050] The double-screw feeder M1 and the feeding belt conveyor M2 are used to lift the materials in the silo into the buffer silo, and the auger feeder M3 is used to drive the materials in the buffer silo to feed into the gasifier.

[0051] The induced draft fan M7 of the gasifier extracts the fuel gas. The oxygen analyzer AI01 feeds back the oxygen content in the fuel gas. The pressure transmitter P03 feeds back the pressure of the fuel gas pipeline. The temperature transmitter TT05 feeds back the temperature of the fuel gas pipeline. The pressure transmitter PT04 feeds back the pressure before the induced draft fan of the fuel gas pipeline.

[0052] The tower grate M4 discharges the carbon slag burned out in the oxidation layer of the gasifier outside the furnace body.

[0053] Embodiment 2

[0054] For the biomass gasifier adaptive regulation and energy-saving control method, the biomass gasifier adaptive regulation and energy-saving control system of Embodiment 1 is adopted. The specific method is as follows:

[0055] Construct as Figure 2 the shown control method flowchart.

[0056] Based on the adaptive regulation control method of the feeding belt conveyor and the double-screw feeder, the feeding amount of the gasifier is adaptively adjusted;

[0057] Based on the adaptive regulation control method of the auger feeding, the feeding amount of the gasifier is adaptively adjusted;

[0058] Based on the adaptive regulation control method of the water jacket circulating water pump of the gasifier, the temperature of the jacket water of the gasifier is adaptively adjusted;

[0059] Based on the adaptive regulation control method of the gasifier blower and the gasifier ring fan, the air supply amount of the gasifier is adaptively adjusted;

[0060] Based on the adaptive regulation control method of the gasifier induced draft fan, the induced air amount of the gasifier is adaptively adjusted;

[0061] Based on the adaptive regulation control method of the tower grate, the slag removal of the gasifier is adaptively adjusted;

[0062] Based on the gasifier ignition control method, the equipment control of the gasifier during start-up ignition;

[0063] Based on the gasifier furnace shutdown control method, the equipment control of the gasifier during furnace shutdown;

[0064] Next, the above-mentioned adaptive controls will be specifically described respectively.

[0065] 1) Adaptive regulation control method of the feeding belt conveyor and the double-screw feeder

[0066] The feeding belt conveyor and the double - screw feeder lift and feed into the buffer bin. The buffer bin is equipped with high - level LT06, medium - level LT05, and low - level LT04 level gauges. After the system starts, the feeding belt conveyor and the double - screw feeder operate with a variable frequency of 25Hz initially. After 10s when there is no level signal from all three level gauges LT06, LT05, and LT04, the variable - frequency of the feeding belt conveyor and the double - screw feeder increases by 1. After the next 10s when there is still no level signal from LT06, LT05, and LT04, the variable - frequency of the feeding belt conveyor and the double - screw feeder increases by 1 again, and so on. When there is a level signal at the low - level of LT06, LT05, and LT04, the variable - frequency of the feeding belt conveyor and the double - screw feeder maintains operation. When there are level signals from LT05 and LT04 among LT06, LT05, and LT04, the variable - frequency of the feeding belt conveyor and the double - screw feeder decreases by 1. After running for another 10s when there are level signals from the medium - and low - levels, the variable - frequency of the feeding belt conveyor and the double - screw feeder decreases by 1 again, and so on. When there is a level signal at the low - level of LT04 among LT06, LT05, and LT04, the variable - frequency of the feeding belt conveyor and the double - screw feeder maintains operation. When there are level signals from all of LT06, LT05, and LT04, the variable - frequency of the feeding belt conveyor and the double - screw feeder stops operating until the level gauges drop to where there are signals from LT05 and LT04, and then the variable - frequency of the feeding belt conveyor and the double - screw feeder starts operating at the frequency when it stopped. Repeat the above control logic to adaptively adjust to a relatively linear feeding frequency range to ensure linear feeding operation. The variable - frequency range of the frequency converter is limited to be adjusted between 10Hz and 50Hz.

[0067] 2) Adaptive adjustment control method for auger feeding

[0068] The auger feeder conveys materials into the horn-shaped cloth bin. The horn-shaped cloth bin is equipped with high LT03, medium LT02, and low LT01 level gauges. After the system starts, the auger feeder runs at an initial frequency of 25Hz. After 10s when there is no level signal from the three level gauges of high LT03, medium LT02, and low LT01, the frequency of the auger feeder inverter increases by 1. After the next 10s when there is still no level signal from high LT03, medium LT02, and low LT01, the frequency of the auger feeder inverter increases by 1 again, and so on. When there is a level signal at the low LT01 level among the high LT03, medium LT02, and low LT01 level signals, the frequency of the auger feeder inverter remains running. When there are level signals at the medium LT02 and low LT01 levels among the high LT03, medium LT02, and low LT01 level signals, the frequency of the auger feeder inverter decreases by 1. After running for another 10s when there are level signals at the medium and low levels, the frequency of the auger feeder inverter decreases by 1 again, and so on. When there is a level signal at the low LT01 level among the high LT03, medium LT02, and low LT01 level signals, the frequency of the auger feeder inverter remains running. When there are level signals from all of the high LT03, medium LT02, and low LT01 level signals, the auger feeder inverter stops running until the level gauges drop to where there are signals at the medium LT02 and low LT01 levels, and then the auger feeder inverter starts running at the frequency when it stopped. Repeat the above control logic to adaptively adjust to a relatively linear frequency range for feeding to ensure linear feeding operation. The frequency adjustment range of the inverter is limited between 10Hz and 50Hz.

[0069] 3) Adaptive adjustment control method for the circulating water pump of the gasifier water jacket

[0070] For the circulating water pump of the gasifier water jacket, a jacket water thermometer TT06 is set in the gasifier water jacket. After the system starts, the frequency converter of the circulating water pump runs at an initial frequency of 20Hz, and the jacket water temperature is monitored in real time. When the water temperature TT06 is lower than 80°C, the frequency converter does not adjust and runs at the initial frequency. When the temperature TT06 is higher than 90°C, the running frequency of the frequency converter increases by 1. After the next 10s when the temperature does not drop to between 80 - 90°C, the running frequency of the frequency converter increases by 1 again, and so on. The frequency remains unchanged when the jacket water temperature TT06 is between 80 - 90°C. When the LT11 / LT12 is at a low level, the system is not allowed to start. During operation, when the LT11 / LT12 is at a low level, the system enters the furnace-smothering state. Repeat the above control logic to adaptively adjust to a relatively linear frequency range for the jacket water temperature TT06 to ensure linear temperature operation. The frequency adjustment range of the frequency converter is limited between 20Hz and 50Hz.

[0071] 4) Adaptive adjustment control method for the gasifier blower and the gasifier annular blower

[0072] Gasifier blower and gasifier annular blower. Temperature transmitters TT01 / TT02 / TT03 / TT04 are installed in the gasifier, a pressure transmitter PT03 is installed, a pressure transmitter PT01 is installed at the inlet of the gasifier blower, and a pressure transmitter PT02 is installed on the gasifier annular blower. After the system starts and operates normally, the blower motorized valve SV1 is fully open, and the blower operates at a starting frequency of 5 Hz. When the temperature values of TT01 / TT02 are higher than 500 °C, the pressure transmitter PT01 at the blower inlet is less than 6 kPa, and the upper layer of the gasifier PT03 operates under a negative pressure of (-100 Pa)-(-20 kPa). When the negative pressure of the upper layer of the gasifier PT03 is less than -15 kPa, the frequency of the blower frequency converter is increased by 1. If the negative pressure of PT03 does not decrease after 5 s, the frequency of the blower frequency converter is increased by 1, and so on. When the negative pressure of the upper layer of the gasifier PT03 is less than -20 kPa, the frequency of the blower frequency converter is increased by 5. If the negative pressure of PT03 is not less than -20 kPa after 5 s, the frequency of the blower frequency converter is increased by 5, and so on. When the temperature values of TT01 / TT02 are higher than 500 °C, the pressure transmitter PT01 at the blower inlet is less than 6 kPa, and the upper layer of the gasifier PT03 operates under a negative pressure of (-5 kPa)-(-15 kPa), the frequency of the frequency converter remains unchanged. When the temperature values of TT01 / TT02 are higher than 500 °C, the pressure transmitter PT01 at the blower inlet is less than 6 kPa, and the upper layer of the gasifier PT03 operates under a negative pressure of (-100 Pa)-(-20 kPa). When the negative pressure of the upper layer of the gasifier PT03 is greater than -5 kPa, the frequency of the blower frequency converter is decreased by 1. If the negative pressure of PT03 does not increase after 5 s, the frequency of the blower frequency converter is decreased by 1, and so on. When the negative pressure of the upper layer of the gasifier PT03 is greater than -1 kPa, the frequency of the blower frequency converter is decreased by 5. If the negative pressure does not increase after 5 s, the frequency of the blower frequency converter is decreased by 5, and so on. When the negative pressure PT03 of the blower exceeds -20 kPa during operation or the operating frequency of the blower reaches 50 Hz, the annular blower starts to adjust the frequency in the same adjustment form as above, the annular blower motorized valve SV2 is fully open. When the negative pressure PT03 is greater than -100 Pa, the annular blower stops operating and closes the motorized valve SV2. The frequency conversion range of the frequency converter is limited to adjustment between 5 Hz and 50 Hz.

[0073] 5) Adaptive adjustment control method for gasifier induced draft fan

[0074] The induced draft fan of the gasifier is adaptively adjusted. A pressure transmitter PT05 and an oxygen sensor AI01 are installed on the gas pipeline. After the system starts, the frequency converter of the induced draft fan of the gasifier starts to run at an initial frequency of 10 Hz. The pressure of the gas pipeline remains between 10 - 20 kPa, and the oxygen sensor AI01 remains below 3%. When the oxygen sensor AI01 is greater than 3%, the frequency of the frequency converter remains unchanged. When the pressure PT05 of the gas pipeline is lower than 12 kPa, the frequency of the induced draft fan of the gasifier increases by 1. If the pressure PT05 of the gas pipeline is still lower than 12 kPa after 5 s, the frequency of the frequency converter of the induced draft fan of the gasifier continues to increase by 1, and so on. When the pressure PT05 of the gas pipeline is in the range of 12 - 18 kPa, the frequency of the induced draft fan inverter remains unchanged. When the pressure PT05 of the gas pipeline is higher than 18 kPa, the frequency of the induced draft fan of the gasifier decreases by 1. If the pressure PT05 of the gas pipeline is still lower than 18 kPa after 5 s, the frequency of the frequency converter of the induced draft fan of the gasifier continues to decrease by 1, and so on. To prevent the lag effect caused by the frequency modulation of the induced draft fan on the pressure inside the gasifier, the blower and the annular fan follow the increase and decrease of the induced draft fan by 1 for adjustment. The frequency conversion range of the frequency converter is limited to adjustment between 5 Hz - 50 Hz.

[0075] 6) Adaptive adjustment control method for the tower grate

[0076] The tower grate is adaptively adjusted. Temperature transmitters TT01 / TT02 / TT03 are set in the oxidation layer and reduction layer of the gasifier. After the system starts and operates normally, the temperatures of the oxidation layer TT01 / TT02 and the reduction layer TT03 are both greater than 500 °C. When the difference between the temperature TT01 / TT02 of the oxidation layer and the temperature TT03 of the reduction layer is less than 100 °C, the tower grate runs at a frequency of 30 Hz. When the difference between the temperature TT01 / TT02 of the oxidation layer and the temperature TT03 of the reduction layer is greater than 150 °C, the grate stops running.

[0077] 7) Gasifier ignition control method for equipment control during gasifier startup and ignition

[0078] Gasifier ignition control method. During gasifier ignition control, the feeding program executes the above-mentioned feeding belt conveyor, double-screw feeder, and auger feeder conveying and the operation program of the gasifier water jacket circulating water pump. The gasifier blower runs at a frequency of 5 Hz, the electric valve SV1 of the gasifier blower is fully open, the induced draft fan of the gasifier does not start, the electric valve SV3 of the gas pipeline is closed, and the pneumatic valves SV12 / SV13 are closed. The drain valve SV11 is fully open. When the temperature TT01 / TT02 of the oxidation layer is greater than 500 °C and there is a slight positive pressure in the upper layer of the gasifier, the ignition gun ignites once every 60 s until ignition is successful. After ignition is successful, close the SV11 drain valve and open the valves SV3, SV12, and SV3 of the gas pipeline, start the induced draft fan of the furnace, and enter the normal operation program.

[0079] Generally speaking, the core idea of using the adaptive adjustment control method in the present invention is to enable the control system to automatically adjust its own structure, parameters or control strategies according to the continuously changing internal and external conditions during the operation of the system, so as to achieve and maintain the optimal or sub-optimal control performance.

[0080] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can 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 these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A biomass gasifier adaptive adjustment energy-saving control system, characterized in that: The utility model comprises a feeding belt conveyor, a double-screw feeder, a buffer silo, an auger feeder, a trumpet-shaped material distribution silo, a gasifier, a gasifier induced draft fan and gas-using equipment which are connected in sequence.

2. The biomass gasifier adaptive regulation energy-saving control system according to claim 1 is characterized in that: High, middle and low material level meters are installed in the buffer silo and the trumpet-shaped material distribution silo.

3. The biomass gasifier adaptive regulation energy-saving control system according to claim 1 is characterized in that: The gasifier is divided into a fuel gas layer, a drying layer, a pyrolysis layer, a reduction layer and an oxidation layer from top to bottom, and a plurality of temperature transmitters and pressure transmitters are installed inside the gasifier from top to bottom.

4. The biomass gasifier adaptive regulation energy-saving control system according to claim 1 is characterized in that: A temperature transmitter and a pressure transmitter are installed on the gas pipeline between the input end of the gasifier induced draft fan and the gasifier; a pressure transmitter and an oxygen analyzer are installed on the gas pipeline between the output end of the gasifier induced draft fan and the gas-using equipment.

5. The biomass gasifier adaptive regulation energy-saving control system according to claim 1 is characterized in that: It also includes a tower grate, a gasifier blower, a gasifier annular fan and a gasifier water jacket circulating water pump which are respectively connected to the gasifier.

6. The biomass gasification furnace adaptive regulation energy-saving control system according to claim 5, characterized in that: Pressure transmitters are respectively installed on the gasifier blower and the pipeline between the gasifier annular fan and the gasifier.

7. A biomass gasifier adaptive regulation energy-saving control method, characterized in that: The biomass gasification furnace adaptive adjustment energy-saving control system according to any one of claims 1 to 6 specifically comprises the following steps: (1) Gasifier ignition control method During the ignition control of the gasifier, the feeding program executes the feeding belt, double screw feeder, auger feeder transportation and the gasifier water jacket circulating water pump operation program, the gasifier blower is running, the gasifier annular fan is running, the electric valve is fully opened, the gasifier induced draft fan is not started, the gas pipeline electric valve is closed, the pneumatic valve is closed, and the drain valve is fully opened. When the temperature of the oxide layer in the gasifier is greater than 500°C and the upper layer of the gasifier is slightly positively pressured, the ignition gun ignites. After the ignition is successful, the drain valve is closed, the gas pipeline valve is opened, the furnace induced draft fan is started, and the normal operation program is entered; (2) Gasifier suffocation control method When the gasifier is stuffy, the feeding program executes the feeding belt, double screw feeder, auger feeder transportation, and the gasifier water jacket circulating water pump and tower grate operation program. The gasifier blower is running, the gasifier annular fan is stopped, the electric valve is closed, the gasifier induced draft fan is not started, the gas pipeline electric valve is closed, the pneumatic valve is closed, and the drain valve is fully opened. When the temperature of the oxide layer in the gasifier is greater than 500°C and the upper layer of the gasifier is slightly positive, the ignition gun ignites. After successful ignition, the temperature of the oxide layer in the gasifier is maintained at not less than 500°C.

8. The biomass gasifier adaptive regulation energy-saving control method according to claim 7, characterized in that: In step (1), the operating frequency of the gasifier blower is 5 Hz; the ignition gun ignites once every 60 seconds until the ignition is successful.

9. The biomass gasifier adaptive regulation energy-saving control method according to claim 7, characterized in that: In step (2), the operating frequency of the gasifier blower is 5 Hz; the ignition gun ignites once every 60 seconds until the ignition is successful.

10. The biomass gasifier adaptive regulation energy-saving control method according to claim 7, characterized in that: In step (2), when the temperature of the oxide layer in the gasifier is lower than 500°C, the frequency of the gasifier blower is increased by 1 every 10 seconds; when the temperature of the oxide layer in the gasifier exceeds 500°C, it is operated at the lowest frequency until the system switches to normal production.

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