Method and device for treating organic waste gas combustion

Abstract

The present invention relates to the field of waste disposal technology, and discloses a method for treating organic waste gas combustion. The method controls the gas output of the secondary combustion furnace and the ignition of a combustion igniter according to the temperature in the secondary combustion furnace. When the temperature in the secondary combustion furnace decreases, the gas output of the secondary combustion furnace is reduced. When the temperature in the secondary combustion furnace is lower than a lower limit set value, the combustion igniter is turned on, entering an ignition stage. The temperature in the secondary combustion furnace increases, and the gas output of the secondary combustion furnace increases as the temperature in the secondary combustion furnace increases. When the temperature in the secondary combustion furnace increases to an upper limit set value, the combustion igniter is turned off, entering a spontaneous combustion stage. The temperature in the secondary combustion furnace is maintained within a certain range, ensuring sufficient combustion of the organic waste gas while reducing fuel usage. The present invention also provides an organic waste gas combustion treatment device for implementing the above method.

Description

Technical Field

[0001] The present invention relates to the technical field of garbage disposal, and in particular to a method and device for treating organic waste gas by combustion. Background Art

[0002] After organic waste is pyrolyzed and gasified in a pyrolysis furnace (or gasification furnace), it produces a mixed exhaust gas containing hydrocarbon compounds, tar, alkanes, alkenes, and residual oxygen. These toxic and hazardous waste gases must be purified and treated to meet standards before they can be discharged. Combustion purification is one effective purification method. This method purifies the waste gas by burning combustibles and thermally decomposing them at high temperatures. Current combustion processes require a constant supply of gas to support combustion, which results in high production costs.

[0003] The prior art discloses a small cabinet-type low-temperature pyrolysis system for garbage and its process, which includes the following steps: ① The garbage is fed into a low-temperature pyrolysis furnace for low-temperature pyrolysis at 200 to 300°C, with the temperature adjusted by the air intake through the oxygen inlet; ② The flue gas generated by the low-temperature pyrolysis is passed into a high-temperature secondary combustion chamber and ignited by an igniter. The temperature in the high-temperature secondary combustion chamber is controlled at 1100-1300°C, and the temperature is adjusted by the oxygen intake through the control tube; ③ The exhaust gas from the high-temperature secondary combustion chamber is passed into a rapid cooling heat exchanger for rapid cooling, and the heat energy generated by the heat exchange is used for power generation or heating; ④ The rapidly cooled exhaust gas enters an exhaust gas treatment unit for one or more of the dust removal, adsorption, desulfurization, and denitrification steps. This patent passes the flue gas generated by pyrolysis into the high-temperature secondary combustion chamber and ignites the flue gas for combustion by an igniter. The igniter needs to be kept working all the time, consuming a lot of fuel and being costly. Summary of the Invention

[0004] The object of the present invention is to provide a method and device for treating organic waste gas combustion, which can ensure the complete combustion of organic waste gas while reducing fuel consumption.

[0005] In order to achieve the above-mentioned objectives, the present invention provides a method for treating the combustion of organic waste gas, which controls the gas output of the secondary combustion furnace and whether the combustion igniter is ignited according to the temperature in the secondary combustion furnace. When the temperature in the secondary combustion furnace decreases, the gas output of the secondary combustion furnace is reduced; when the temperature in the secondary combustion furnace is lower than the lower limit setting value, the combustion igniter is turned on and the ignition stage is entered. The temperature in the secondary combustion furnace increases, and the gas output of the secondary combustion furnace increases as the temperature in the secondary combustion furnace increases; when the temperature in the secondary combustion furnace increases to the upper limit setting value, the combustion igniter is turned off and the self-ignition stage is entered; so that the temperature in the secondary combustion furnace is maintained within a certain range.

[0006] As a preferred solution, the secondary combustion furnace adopts a layout with air intake at the bottom and air outlet at the top, and the combustion igniter is arranged at the bottom of the secondary combustion furnace.

[0007] As a preferred solution, the temperature of the upper, middle and lower sections of the secondary combustion furnace are detected respectively;

[0008] When the temperature of the upper section of the secondary combustion furnace is higher than the first set value, and / or the temperature of the middle section of the secondary combustion furnace is higher than the second set value, the combustion igniter is turned off and the auto-ignition stage is entered, and the gas output of the secondary combustion furnace decreases as the temperature of the middle section of the secondary combustion furnace decreases;

[0009] When the middle section temperature in the secondary combustion furnace is lower than the third set value, and the lower section temperature in the secondary combustion furnace is lower than the fourth set value, the combustion igniter is turned on and the ignition stage is entered. The gas output of the secondary combustion furnace increases with the increase of the lower section temperature in the secondary combustion furnace.

[0010] As a preferred solution, the secondary combustion furnace is connected to a fan to achieve gas outlet. The gas outlet of the secondary combustion furnace is positively correlated with the frequency of the fan. Assuming the minimum operating frequency of the fan is F1,

[0011] During the ignition phase, the fan frequency F2 is:

[0012] F2=(temperature of the lower section of the secondary combustion furnace - K1) / K2+F1,

[0013] Among them, K1 and K2 are empirical values, which are the coefficients for converting the temperature in the secondary combustion furnace into the fan frequency;

[0014] During the spontaneous combustion stage, the fan frequency F3 is:

[0015] F3=F MAX +∑(△F1+△F2+△F3+……+△F t ),

[0016] Among them, F MAX is the maximum frequency of the fan during the ignition stage, △F t is the frequency change within a certain sampling period t; and △F t = kt, where k is the minimum frequency change setting value and t is the sampling time. When the temperature rises, k is a positive value, and when the temperature drops, k is a negative value.

[0017] As a preferred solution, multiple thermocouples are arranged in the secondary combustion furnace to monitor the temperature in the secondary combustion furnace. The multiple thermocouples are arranged in sequence from bottom to top, and one of the thermocouples is used to detect whether the combustion igniter is ignited.

[0018] As a preferred solution, the secondary combustion furnace is preheated before air is introduced into the secondary combustion furnace. During the preheating, the combustion igniter is turned on while maintaining the minimum gas output of the secondary combustion furnace.

[0019] As a preferred solution, when the ratio of the time of the ignition stage to the time of the self-ignition stage exceeds a certain value, the gas output of the secondary combustion furnace is reduced.

[0020] The present invention also provides an organic waste gas combustion treatment device, including a secondary combustion furnace, a combustion igniter, a fan, an air inlet pipe and an air outlet pipe. The secondary combustion furnace is provided with an air inlet and an air outlet communicated with its interior. The air inlet pipe is connected to the air inlet, the air outlet is communicated with the air inlet end of the fan, the air outlet end of the fan is connected to the air outlet pipe, the combustion igniter is arranged inside the secondary combustion furnace, and the system also includes a programmable controller, a wind speed sensor and a thermocouple. The wind speed sensor is arranged in the air outlet pipe, and the wind speed sensor is used to detect the air outlet volume of the secondary combustion furnace. The thermocouple is arranged in the secondary combustion furnace, and the thermocouple is used to detect the temperature inside the secondary combustion furnace. The wind speed sensor, the thermocouple and the fan are communicatively connected to the programmable controller.

[0021] As a preferred embodiment, the air inlet and the air outlet are both arranged on the side wall of the secondary combustion furnace, and the air inlet is located at the bottom of the secondary combustion furnace, the air outlet is arranged at the top of the secondary combustion furnace, the combustion igniter is arranged at the bottom of the secondary combustion furnace, and the number of thermocouples is at least three, and the thermocouples are arranged in sequence from bottom to top.

[0022] As a preferred solution, the air intake pipe is provided with a regulating valve, and the regulating valve is communicatively connected to the programmable controller.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention controls the gas output of the secondary combustion furnace according to the temperature in the secondary combustion furnace. After the first ignition, when the temperature in the secondary combustion furnace reaches an upper limit setting value, the combustion igniter is turned off, allowing the organic waste gas to spontaneously combust in the secondary combustion furnace. At the same time, as the temperature in the secondary combustion furnace decreases, the gas output is reduced, allowing the high-temperature gas to stay in the secondary combustion furnace for a long time, so that the secondary combustion furnace is maintained at a certain high temperature, allowing the organic waste gas originally in the secondary combustion furnace to be fully decomposed, and at the same time, allowing the entering organic waste gas to be thermally decomposed at a high temperature, thereby ensuring that the organic waste gas is fully burned while reducing the use of the combustion igniter fuel. Moreover, when the temperature in the secondary combustion furnace is lower than the lower limit setting value, the combustion igniter is turned on, which can heat the secondary combustion furnace, causing the temperature in the secondary combustion furnace to rise. As the temperature in the secondary combustion furnace rises, the gas output is also increased. Because the temperature rises, the combustion efficiency of the organic waste gas is high. The increased gas output can timely discharge the gas that has been burned, thereby improving the treatment efficiency of the organic waste gas, and helping to quickly increase the temperature in the secondary combustion furnace, reducing the use of fuel, and making the secondary combustion furnace economical and efficient. Furthermore, the present invention also provides an organic waste gas combustion treatment device, wherein the programmable controller controls the ignition of the fan and the combustion igniter through feedback from the wind speed sensor and the thermocouple, thereby realizing the above method. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of an organic waste gas combustion treatment device according to an embodiment of the present invention.

[0026] Figure 2 Schematic diagram of the structure of the secondary combustion furnace according to an embodiment of the present invention.

[0027] Figure 3 It is a principle block diagram of the organic waste gas combustion treatment device according to an embodiment of the present invention.

[0028] In the figure, 1-secondary combustion furnace; 2-combustion igniter; 3-fan; 4-air inlet pipe; 5-air outlet pipe; 6-regulating valve; 7-wind speed sensor; 8-first thermocouple; 9-second thermocouple; 10-third thermocouple; 11-fourth thermocouple; 12-fifth thermocouple; 13-quenching tower; 14-dust removal equipment; 15-pressure relief device. DETAILED DESCRIPTION

[0029] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0032] Furthermore, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0033] Example 1

[0034] like Figure 1 As shown, a method for treating combustion of organic waste gas according to a preferred embodiment of the present invention controls the gas output of the secondary combustion furnace 1 according to the temperature in the secondary combustion furnace 1. When the temperature in the secondary combustion furnace 1 decreases, the gas output of the secondary combustion furnace 1 is reduced; when the temperature in the secondary combustion furnace 1 is lower than the lower limit set value, the combustion igniter 2 is turned on to enter the ignition stage, the temperature in the secondary combustion furnace 1 increases, and the gas output of the secondary combustion furnace 1 increases as the temperature in the secondary combustion furnace 1 increases; when the temperature in the secondary combustion furnace 1 increases to the upper limit set value, the combustion igniter 2 is turned off to enter the self-ignition stage; the temperature in the secondary combustion furnace 1 is maintained within a certain range.

[0035] This embodiment controls the gas output of the secondary combustion furnace 1 and whether the combustion igniter 2 is ignited according to the temperature in the secondary combustion furnace 1. After the first ignition, when the temperature in the secondary combustion furnace 1 reaches the upper limit set value, the combustion igniter 2 is turned off to allow the organic waste gas to spontaneously combust in the secondary combustion furnace 1. At the same time, as the temperature in the secondary combustion furnace 1 decreases, its gas output is reduced, so that the high-temperature gas can stay in the secondary combustion furnace 1 for a longer time, so that the secondary combustion furnace 1 is maintained at a certain high temperature, so that the organic waste gas originally in the secondary combustion furnace 1 can be fully decomposed, and at the same time, the incoming organic waste gas is thermally decomposed at high temperature, thereby ensuring the full combustion of the organic waste gas while reducing the use of fuel for the combustion igniter 2. Moreover, when the temperature in the secondary combustion furnace 1 is lower than the lower limit set value, the combustion igniter 2 is turned on to heat the secondary combustion furnace 1, so that the temperature in the secondary combustion furnace 1 rises. As the temperature in the secondary combustion furnace 1 rises, its gas output also increases. Because the temperature rises, the combustion efficiency of the organic waste gas is high. Increasing the gas output can discharge the burned gas in time, improve the treatment efficiency of the organic waste gas, and help the temperature in the secondary combustion furnace 1 to rise quickly, reduce the use of fuel, and make the secondary combustion furnace 1 operate economically and efficiently.

[0036] In this embodiment, the secondary combustion furnace 1 adopts a bottom-intake, top-outlet layout, and the combustion igniter 2 is disposed at the bottom of the secondary combustion furnace 1. Based on the principle that gas rises when heated, the bottom-intake and top-outlet layout of the secondary combustion furnace 1 allows the organic waste gas entering the secondary combustion furnace 1 to remain within the secondary combustion furnace 1 for a longer period of time, ensuring that the organic waste gas passes through the hot zone, allowing the organic waste gas to be fully pyrolyzed and fully purified.

[0037] Specifically, this embodiment performs temperature detection on the upper section, middle section and lower section of the secondary combustion furnace 1 respectively; when the temperature of the upper section of the secondary combustion furnace 1 is higher than the first set value, and / or the temperature of the middle section of the secondary combustion furnace 1 is higher than the second set value, the combustion igniter 2 is turned off, and the self-ignition stage is entered, and the gas output of the secondary combustion furnace 1 decreases as the temperature of the middle section of the secondary combustion furnace 1 decreases; when the temperature of the middle section of the secondary combustion furnace 1 is lower than the third set value, and the temperature of the lower section of the secondary combustion furnace 1 is lower than the fourth set value, the combustion igniter 2 is turned on, and the ignition stage is entered, and the gas output of the secondary combustion furnace 1 increases as the temperature of the lower section of the secondary combustion furnace 1 increases. The temperature inside the secondary combustion furnace body 1 decreases from bottom to top. Therefore, when either the upper or middle temperature inside the secondary combustion furnace 1 is higher than the set value, the combustion igniter 2 is turned off. This indicates that the temperature inside the secondary combustion furnace body 1 is high enough for the organic waste gas to undergo thermal decomposition. When both the middle and lower temperatures inside the secondary combustion furnace body 1 are lower than the set value, this indicates that the temperature inside the secondary combustion furnace body 1 is low, and the organic waste gas entering the secondary combustion furnace body 1 will not be fully burned. In this case, the combustion igniter 2 is required to heat the secondary combustion furnace body 1 to ensure that the organic waste gas is fully treated. This embodiment adjusts the gas output according to the lower temperature inside the secondary combustion furnace 1 during the ignition stage, and adjusts the gas output according to the middle temperature inside the secondary combustion furnace 1 during the self-ignition stage.

[0038] The secondary combustion furnace 1 has a lower intake air section, which has a relatively low intake air temperature (less than 200°C). The lower section temperature is lower than the middle section temperature. When the combustion igniter 2 heats and ignites the combustible material in the organic waste gas entering the lower section, the heat of the organic waste gas rises and the combustion of the organic waste gas generates heat. The temperatures of the middle and upper sections gradually rise, and the organic waste gas preferentially burns in the middle section, while the remaining unburned organic waste gas burns in the upper section. After entering the spontaneous combustion stage, the temperature of the lower section of the secondary combustion furnace 1 decreases over time, while the temperature of the middle section gradually decreases and combustion extinguishes, while the upper section continues to burn. Therefore, when the temperatures of both the middle and lower sections are lower than the set values, spontaneous combustion ends and the ignition stage begins, repeating the cycle. Therefore, this embodiment determines whether to ignite and controls the gas output based on the temperatures of the lower, middle, and upper sections of the secondary combustion furnace 1, reducing fuel usage while ensuring sufficient combustion of the organic waste gas.

[0039] In this embodiment, the secondary combustion furnace 1 is connected to a fan 3 to achieve gas exhaust. The gas output of the secondary combustion furnace 1 is positively correlated with the frequency of the fan 3. In this embodiment, the fan 3 exhausts the secondary combustion furnace 1, thereby discharging the post-combustion gases in the secondary combustion furnace 1. The secondary combustion furnace 1 operates at a negative pressure. When the frequency of the fan 3 is high, the gas output of the secondary combustion furnace 1 is large. When the frequency of the fan 3 is low, the gas output of the secondary combustion furnace 1 is small.

[0040] Assume that the minimum operating frequency of fan 3 is F1. The minimum operating frequency of fan 3 is determined according to the model and performance of the selected fan 3.

[0041] During the ignition phase, the frequency F2 of fan 3 is:

[0042] F2=(temperature of the lower section of the secondary combustion furnace - K1) / K2+F1,

[0043] K1 and K2 are empirical values, representing coefficients that convert the temperature within the secondary combustion furnace 1 into gas output. Secondary combustion furnaces 1 and fan 3 systems of varying capacities will have different K1 and K2 values. The above formula derives the frequency range of fan 3 from the temperature range of the lower section within the secondary combustion furnace 1. In this embodiment, K1 = 33.0°C and K2 = 36.0°C. During the ignition phase, the frequency of fan 3 is gradually increased according to the above formula to ensure continued and adequate combustion of the organic waste gas originally within the secondary combustion furnace 1.

[0044] During the spontaneous combustion stage, the frequency F3 of fan 3 is:

[0045] F3=F MAX +∑(△F1+△F2+△F3+……+△F t ),

[0046] Among them, F MAX is the maximum frequency of fan 3 during the ignition stage, △F t is the frequency change within a certain sampling period t; and △F t = kt, where k is the minimum frequency change setting and t is the sampling time. When the temperature rises, k is positive, and when the temperature drops, k is negative. When t=1, ΔF1 is the frequency change of Fan 3 during the first second; when t=2, ΔF2 is the frequency change of Fan 3 during the second second; when t=3, ΔF3 is the frequency change of Fan 3 during the third second, and so on.

[0047] In this embodiment, when either the upper or middle temperature within the secondary combustion furnace 1 exceeds its set temperature, the combustion igniter 2 is turned off, ignition is stopped, and the secondary combustion furnace 1 enters the self-ignition stage, consuming no external energy. During the self-ignition stage, the frequency of the fan 3 is adjusted based on the change in the middle temperature within the secondary combustion furnace 1, specifically adjusting the gas output of the secondary combustion furnace 1 to maintain the self-ignition temperature within the secondary combustion furnace 1 at a high level. At the same time, the frequency of the fan 3 is kept as high as possible. As the self-ignition temperature within the secondary combustion furnace 1 decreases, the frequency of the fan 3 is also reduced to maintain the temperature within the secondary combustion furnace 1. When both the middle and lower temperatures within the secondary combustion furnace 1 fall below the set value, the combustion igniter 2 is turned on, ignition is initiated, and the secondary combustion furnace 1 enters the ignition stage. The frequency of the fan 3 gradually increases as the lower temperature within the secondary combustion furnace 1 increases, and the temperature within the secondary combustion furnace 1 rises, re-entering the self-ignition stage. This cycle repeats, and the duration of the self-ignition and ignition stages is recorded. Furthermore, the frequency of the fan 3 in this embodiment must be within its operating upper and lower limits.

[0048] In addition, in this embodiment, multiple thermocouples are provided within the secondary combustion furnace 1 to monitor the temperature within the secondary combustion furnace 1. The multiple thermocouples are arranged sequentially from bottom to top, and one of the thermocouples is used to detect whether the combustion igniter 2 is in the ignition state. Using a thermocouple to detect whether the combustion igniter 2 is in the ignition state can be used to determine whether the combustion igniter 2 is functioning properly. If the combustion igniter 2 is ignited, the thermocouple will detect a temperature increase. If the combustion igniter 2 is not ignited, the temperature of the thermocouple will be similar to that of the thermocouples adjacent to it, and the temperature detected by the thermocouple will be similar to the temperature at the last sampling time.

[0049] Example 2

[0050] The difference between this embodiment and the first embodiment is that, based on the first embodiment, this embodiment further illustrates the method for treating organic waste gas by combustion.

[0051] In this embodiment, before air is introduced into the secondary combustion furnace 1 , the secondary combustion furnace 1 is preheated so that the organic waste gas entering the secondary combustion furnace 1 can be fully thermally decomposed.

[0052] Specifically, in this embodiment, during preheating, the combustion igniter 2 is turned on while maintaining the minimum gas output of the secondary combustion furnace 1 .

[0053] In addition, in this embodiment, when the ratio of the time of the ignition stage to the time of the self-ignition stage exceeds a certain value, the gas output of the secondary combustion furnace 1 is reduced. Because when the ratio of the time of the ignition stage to the time of the self-ignition stage exceeds a certain value, it means that the organic waste gas entering the secondary combustion furnace 1 is insufficient, and it is necessary to increase the air intake. Reducing the gas output can maintain the temperature of the secondary combustion furnace 1 and avoid incomplete combustion of the organic waste gas in the existing secondary combustion furnace 1. In this embodiment, the time of the ignition stage / the time of the self-ignition stage>2, which means that the organic waste gas is insufficient. It should be pointed out that the above-mentioned time of the ignition stage and the time of the self-ignition stage are calculated from the time when the organic waste gas enters the secondary combustion furnace 1, and no judgment is made when the secondary combustion furnace 1 is preheated.

[0054] In addition, the temperature within the secondary combustion furnace 1 of this embodiment is controlled between 850°C and 1100°C. That is, the temperature within the secondary combustion furnace 1 of this embodiment must be maintained at 850°C or above to ensure the purification rate of the organic waste gas. It should be noted that the minimum temperature within the secondary combustion furnace 1 can be determined based on the composition of the organic waste gas.

[0055] The other processes of this embodiment are the same as those of the first embodiment and will not be described again here.

[0056] Example 3

[0057] like Figures 1 to 3 As shown, this embodiment provides an organic waste gas combustion treatment device for implementing the above method, including a secondary combustion furnace 1, a combustion igniter 2, a blower 3, an air inlet pipe 4, an air outlet pipe 5, a programmable controller, a wind speed sensor 7 and several thermocouples. The secondary combustion furnace 1 is provided with an air inlet and an air outlet communicating with the interior thereof, the air inlet pipe 4 is connected to the air inlet, the air outlet is connected to the air inlet end of the blower 3, the air outlet end of the blower 3 is connected to the air outlet pipe 5, the combustion igniter 2 is arranged inside the secondary combustion furnace 1, the wind speed sensor 7 is arranged in the air outlet pipe 5, the wind speed sensor 7 is arranged in the air outlet pipe 5, the wind speed sensor 7 is used to detect the air output of the secondary combustion furnace 1, the thermocouple is arranged in the secondary combustion furnace 1, the thermocouple is used to detect the temperature of the secondary combustion furnace 1, the wind speed sensor 7, the thermocouple and the blower 3 are communicatively connected to the programmable controller. The programmable controller of this embodiment controls whether the blower 3 and the combustion igniter 2 are ignited or not through feedback from the wind speed sensor 7 and the thermocouple, forming a closed-loop control.

[0058] Furthermore, the air inlet and air outlet of the present embodiment are both arranged on the side wall of the secondary combustion furnace 1, and the air inlet is located at the bottom of the secondary combustion furnace 1, the air outlet is arranged at the top of the secondary combustion furnace 1, the combustion igniter 2 is arranged at the bottom of the secondary combustion furnace 1, and the number of thermocouples is at least three, and the thermocouples are arranged in sequence from bottom to top. The secondary combustion furnace 1 adopts a layout of bottom air intake and top air outlet, and the combustion igniter 2 is arranged at the bottom of the secondary combustion furnace 1. That is, the air inlet is arranged on the lower side wall of the secondary combustion furnace 1, and the air outlet is arranged on the upper side wall of the secondary combustion furnace 1. According to the principle that gas rises when heated, the bottom air intake and top air outlet of the secondary combustion furnace 1 can enable the organic waste gas entering the secondary combustion furnace 1 to stay in the secondary combustion furnace 1 for a longer time, and ensure that the organic waste gas passes through the hot zone, so that the organic waste gas can be burned and pyrolyzed in the lower, middle and upper sections of the secondary combustion furnace 1. In addition, at least three thermocouples spaced from bottom to top are provided in the secondary combustion furnace 1 to detect the temperatures of the upper, middle and lower sections of the secondary combustion furnace 1 .

[0059] In addition, the intake pipe 4 of this embodiment is equipped with a regulating valve 6, which is communicatively connected to a programmable controller to control the amount of organic waste gas entering the secondary combustion furnace 1. Furthermore, the system of this embodiment includes a human-computer interaction device, which is communicatively connected to the programmable controller. This device can be used to view the detection data of the wind speed sensor 7 and each thermocouple, the ignition timing of the combustion igniter 2, and adjust the set temperature value within the secondary combustion furnace 1. The detection data of the wind speed sensor 7 and the thermocouples is represented by a continuous curve for easy monitoring.

[0060] The regulating valve 6 of this embodiment is an electric regulating valve, which can arbitrarily adjust the flow rate of the organic waste gas entering the secondary combustion furnace 1. The control signal and feedback signal of the regulating valve 6 are connected to the programmable controller.

[0061] Combustion igniter 2 is connected to an external device that receives decompressed gas (e.g., natural gas or liquefied petroleum gas). Its control and feedback signals are connected to a programmable controller. During the ignition phase, combustion igniter 2 automatically controls the combustion ratio of external gas and air to maintain an optimal combustion flame and prevent excess air from entering the secondary combustion furnace 1. When combustion igniter 2 is not operating, the external gas and air channels are closed, preventing gas from entering the secondary combustion furnace 1.

[0062] In this embodiment, five thermocouples are provided: a first thermocouple 8, a second thermocouple 9, a third thermocouple 10, a fourth thermocouple 11, and a fifth thermocouple 12. These thermocouples are evenly spaced from bottom to top. The first and second thermocouples 8 and 9 detect the temperature of the lower section of the secondary combustion furnace 1. The second thermocouple 9 also detects whether the combustion igniter 2 is in the ignition state. The third thermocouple 10 detects the temperature of the middle section of the secondary combustion furnace 1. The fourth and fifth thermocouples 11 and 12 detect the temperature of the upper section of the secondary combustion furnace 1. When determining the temperature of the lower section of the secondary combustion furnace 1, the average of the detection values ​​of the first and second thermocouples 8 and 9 is used during the self-ignition phase, and the detection value of the first thermocouple 8 is used during the ignition phase. When determining the temperature of the upper section of the secondary combustion furnace 1, the average of the detection values ​​of the fourth and fifth thermocouples 11 and 12 is used. The signal of the thermocouple is connected to the programmable controller.

[0063] The organic waste gas combustion treatment device of this embodiment also includes a quenching tower 13 and a dust removal device 14. The air outlet on the top surface of the secondary combustion furnace 1 is connected to the top of the quenching tower 13, the bottom of the quenching tower 13 is connected to the bottom of the dust removal device 14, and the top of the dust removal device 14 is connected to a fan 3. The fan 3 provides power to exhaust gases from the secondary combustion furnace 1, passing through the quenching tower 13 and the dust removal device 14 before being discharged. In this embodiment, the fan 3 is installed at the rear end of the system, serving as the sole power source for the entire organic waste gas treatment device, ensuring that the system operates at a constant slight negative pressure. The rear end of the fan 3 is connected to the exhaust chimney. The fan 3 is driven by a frequency converter, which can continuously adjust the wind speed of the fan 3 to adjust the air volume. The frequency converter control and feedback signals are connected to a programmable controller. A wind speed sensor 7 is installed in the outlet pipe 5 connected to the fan 3 to monitor the outlet wind speed in real time. The signal from the wind speed sensor 7 is connected to the programmable controller. In this embodiment, the wind speed sensor 7 detects the wind speed of the fan 3 to ensure that the fan 3 is within its operating upper and lower limits, thereby ensuring normal operation of the fan 3. The top surface of the secondary combustion furnace 1 of this embodiment is further provided with a pressure relief device 15 communicated with the interior thereof to ensure the safe operation of the secondary combustion furnace 1 .

[0064] The thermocouple detects the temperature of each section in the secondary combustion furnace 1 in real time and is an important detection component for achieving stable combustion in the secondary combustion furnace 1. The wind speed sensor 7 is a safe operation detection component. The regulating valve 6 and the fan 3 are the executive components for adjusting the air volume. The combustion igniter 2 is an executive component for external energy supplementation and is an important device for ensuring the combustion treatment effect; the programmable controller is the central processor of the automatic control system, which receives the signals from each sensor, and after processing according to the combustion algorithm, automatically outputs signals to continuously and uninterruptedly control the operation of each executive component, so that the system can operate efficiently, economically and safely; the human-computer interaction device is connected to the programmable controller for communication and can perform system parameter setting, feedback signal viewing, status viewing, operation data storage and viewing, etc. The human-computer interaction device of this embodiment uses a touch screen.

[0065] At the beginning of operation, the organic waste gas combustion treatment device of this embodiment first closes the regulating valve 6 at the front section of the secondary combustion furnace 1 to stop extracting organic waste gas; then starts the fan 3, and the fan 3 runs at the lowest frequency; then starts the combustion igniter 2 at the bottom of the secondary combustion furnace 1, and the secondary combustion furnace 1 enters the ignition stage, and preheats the secondary combustion furnace 1 according to the temperature and time required by the process.

[0066] After the secondary combustion furnace 1 is preheated, the regulating valve 6 on the inlet pipe 4 at the front section of the secondary combustion furnace 1 is opened, allowing the organic waste gas from the front section to enter the secondary combustion furnace 1 for combustion treatment. A programmable controller receives temperature feedback from thermocouples in each section of the secondary combustion furnace 1 and controls the frequency converter to adjust the frequency of fan 1 to adjust the air volume according to the internal process parameters of the secondary combustion furnace 1. It also controls the start and stop of the combustion igniter 2, ensuring efficient and economical treatment of the organic waste gas. The internal process includes determining the start and stop of the combustion igniter 2, changing the frequency of fan 1, and implementing safety linkages. These three processes are both independent and interconnected. If the temperature feedback from the upper section of the secondary combustion furnace 1 exceeds the set temperature and / or the temperature feedback from the middle section exceeds the set temperature, the combustion igniter 2 stops ignition, and the secondary combustion furnace 1 enters a self-ignition operating state, consuming no external energy. The frequency of fan 3 is controlled based on the temperature feedback from the middle section and the programmable controller to maintain the self-ignition temperature in the secondary combustion furnace 1 as high as possible and the air speed as high as possible. As the self-ignition temperature decreases, the air speed also decreases, prioritizing maintaining the temperature in the secondary combustion furnace 1. When the temperature of the middle section and the lower section in the secondary combustion furnace 1 are both lower than the set temperature value, the combustion igniter 2 starts to ignite, and the secondary combustion furnace 1 enters the ignition working state. The frequency of the fan 3 gradually increases with the temperature feedback of the lower section in the secondary combustion furnace 1. The temperature gradually increases, and the secondary combustion furnace 1 enters the spontaneous combustion stage again. This cycle repeats itself, and the programmable controller records the cycle time of the spontaneous combustion stage and the ignition stage.

[0067] When the ratio of the ignition phase time to the self-ignition phase time recorded by the programmable controller exceeds a certain value, it indicates that the front-end organic waste gas feed is insufficient, prompting the front-end to add feed, reduce the frequency of fan 3, or increase the opening of regulating valve 6. If the organic waste gas feed continues to be insufficient, the regulating valve 6 is closed, the frequency of fan 3 is reduced to the minimum, and the combustion igniter 2 and fan 3 are stopped according to the temperature and time required by the shutdown process.

[0068] In summary, an embodiment of the present invention provides a method for combustion treatment of organic waste gas, which controls the gas output of the secondary combustion furnace 1 according to the temperature in the secondary combustion furnace 1. After the first ignition, when the temperature in the secondary combustion furnace 1 reaches the upper limit set value, the combustion igniter 2 is turned off to allow the organic waste gas to self-ignite in the secondary combustion furnace 1. At the same time, as the temperature in the secondary combustion furnace 1 decreases, its gas output is reduced, so that the high-temperature gas can stay in the secondary combustion furnace 1 for a long time, and the secondary combustion furnace 1 is maintained at a certain high temperature, so that the organic waste gas originally in the secondary combustion furnace 1 can be fully decomposed, and at the same time, the entering organic waste gas is thermally decomposed at high temperature, thereby ensuring the full combustion of the organic waste gas while reducing the use of fuel in the combustion igniter 2. Furthermore, when the temperature in the secondary combustion furnace 1 is lower than the lower limit set value, the combustion igniter 2 is turned on, which can heat the secondary combustion furnace 1, causing the temperature in the secondary combustion furnace 1 to rise. As the temperature in the secondary combustion furnace 1 rises, its gas output also increases. Because the temperature rises, the combustion efficiency of the organic waste gas is high. Increasing the gas output can timely discharge the burned gas, improve the treatment efficiency of the organic waste gas, and help the temperature in the secondary combustion furnace 1 to rise rapidly, reduce fuel usage, and make the secondary combustion furnace 1 operate economically and efficiently. The embodiment of the present invention also provides an organic waste gas combustion treatment device that implements the above method.

[0069] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A method for treating organic waste gas by combustion, characterized in that: The gas output of the secondary combustion furnace and the ignition of the combustion igniter are controlled according to the temperature in the secondary combustion furnace. When the temperature in the secondary combustion furnace decreases, the gas output of the secondary combustion furnace is reduced. When the temperature in the secondary combustion furnace is lower than the lower limit setting value, the combustion igniter is turned on and the ignition stage is entered. When the temperature in the secondary combustion furnace increases, the gas output of the secondary combustion furnace increases as the temperature in the secondary combustion furnace increases. When the temperature in the secondary combustion furnace increases to the upper limit setting value, the combustion igniter is turned off and the self-ignition stage is entered. The temperature in the secondary combustion furnace is maintained within a certain range. Conduct temperature tests on the upper, middle and lower sections of the secondary combustion furnace respectively; When the temperature of the upper section of the secondary combustion furnace is higher than the first set value, and / or the temperature of the middle section of the secondary combustion furnace is higher than the second set value, the combustion igniter is turned off and the auto-ignition stage is entered, and the gas output of the secondary combustion furnace decreases as the temperature of the middle section of the secondary combustion furnace decreases; When the middle section temperature in the secondary combustion furnace is lower than the third set value, and the lower section temperature in the secondary combustion furnace is lower than the fourth set value, the combustion igniter is turned on and the ignition stage is entered. The gas output of the secondary combustion furnace increases with the increase of the lower section temperature in the secondary combustion furnace.

2. The method for treating organic waste gas by combustion according to claim 1, characterized in that: The secondary combustion furnace adopts a layout of bottom air intake and top air outlet, and the combustion igniter is arranged at the bottom of the secondary combustion furnace.

3. The method for treating organic waste gas by combustion according to claim 1, characterized in that: The secondary combustion furnace is connected to the fan to realize gas outlet. The gas outlet of the secondary combustion furnace is positively correlated with the frequency of the fan. Assuming the minimum operating frequency of the fan is F1, During the ignition phase, the fan frequency F2 is: F2=(temperature of the lower section of the secondary combustion furnace - K1) / K2+F1, Among them, K1 and K2 are empirical values, which are the coefficients for converting the temperature in the secondary combustion furnace into the fan frequency; During the spontaneous combustion stage, the fan frequency F3 is: <h2 style=";text-align:left;direction:ltr">F3=F<h2 style=";text-align:left;direction:ltr"> MAX <h2 style=";text-align:left;direction:ltr"> +∑(△F1+△F2+△F3+……+△F<h2 style=";text-align:left;direction:ltr"> t <h2 style=";text-align:left;direction:ltr"> ), Among them, F MAX is the maximum frequency of the fan during the ignition stage, △F t is the frequency change within a certain sampling period t; and △F t = kt, where k is the minimum frequency change setting value and t is the sampling time. When the temperature rises, k is a positive value, and when the temperature drops, k is a negative value.

4. The method for treating organic waste gas by combustion according to claim 1, characterized in that: A plurality of thermocouples are arranged in the secondary combustion furnace to monitor the temperature in the secondary combustion furnace. The plurality of thermocouples are arranged in sequence from bottom to top, and one of the thermocouples is used to detect whether the combustion igniter is in an ignition state.

5. The method for treating organic waste gas by combustion according to claim 1, characterized in that: Before the air is introduced into the secondary combustion furnace, the secondary combustion furnace is preheated. During the preheating, the combustion igniter is turned on while maintaining the minimum air output of the secondary combustion furnace.

6. The method for treating organic waste gas by combustion according to claim 1, characterized in that: When the ratio of the time of the ignition stage to the time of the self-ignition stage exceeds a certain value, the gas output of the secondary combustion furnace is reduced.

7. An organic waste gas combustion treatment device, using the treatment method according to any one of claims 1 to 6, comprising a secondary combustion furnace (1), a combustion igniter (2), a fan (3), an air inlet pipe (4) and an air outlet pipe (5), wherein the secondary combustion furnace (1) is provided with an air inlet and an air outlet communicated with the interior thereof, the air inlet pipe (4) is connected to the air inlet, the air outlet is communicated with the air inlet end of the fan (3), the air outlet end of the fan (3) is connected to the air outlet pipe (5), the combustion igniter (2) is arranged inside the secondary combustion furnace (1), and is characterized in that, The invention also includes a programmable controller, a wind speed sensor (7) and a thermocouple, wherein the wind speed sensor (7) is arranged in the air outlet pipe (5), and the wind speed sensor (7) is used to detect the air outlet volume of the secondary combustion furnace (1); the thermocouple is arranged in the secondary combustion furnace (1), and the thermocouple is used to detect the temperature of the secondary combustion furnace (1); the wind speed sensor (7), the thermocouple and the fan (3) are communicatively connected to the programmable controller.

8. The organic waste gas combustion treatment device according to claim 7, characterized in that: The air inlet and the air outlet are both arranged on the side wall of the secondary combustion furnace (1), and the air inlet is located at the bottom of the secondary combustion furnace (1), the air outlet is arranged at the top of the secondary combustion furnace (1), the combustion igniter (2) is arranged at the bottom of the secondary combustion furnace (1), and the number of the thermocouples is at least three, and the thermocouples are arranged in sequence from bottom to top.

9. The organic waste gas combustion treatment device according to claim 7, characterized in that: The air intake pipe (4) is provided with a regulating valve (6), and the regulating valve (6) is communicatively connected to the programmable controller.

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