Domestic waste incinerator and furnace secondary air distribution control method

Abstract

The present application discloses a domestic waste incinerator and a method for controlling secondary air distribution in a furnace, wherein the angle between the front arch wall surface of the furnace and the horizontal is 25°, the angle between the rear arch wall surface and the horizontal is 35°, a flame folding angle and an ignition burner are arranged on the rear arch, the inlet of the first flue is located in the front middle part of the furnace, the first flue is surrounded by water-cooled walls, the water-cooled walls extend to the middle part of the refractory furnace wall along with the front arch, the rear arch, the side wall and the flame folding angle, a secondary air duct group is arranged at the lower part of the first flue, and the air outlet of the secondary air duct group forms a double elliptical flow field in the first flue. It can be seen that the design method of the secondary air duct of the flue has a stronger anti-interference ability than the double tangent circle, and can still increase the flue gas disturbance, improve the uniformity of the flow field and protect the wall surface from overheating when the combustion conditions change frequently. By increasing the inclination angle of the rear arch and increasing the flame folding angle, the stable combustion effect of the furnace is improved, and the newly-entered garbage is easier to dry, precipitate volatiles, and ignite, thereby enhancing the stable combustion ability of the incinerator.

Description

Technical Field

[0001] The present application relates to the technical field of waste incineration equipment, and more specifically, to a domestic waste incinerator and a furnace secondary air distribution control method. Background Art

[0002] As the pace of life accelerates, the amount of domestic waste generated by people also increases. In order to meet the needs of urban beautification and environmental protection, people's domestic waste needs to be incinerated. Most of the existing domestic waste incinerators are downstream or central flow.

[0003] The first flue of the downstream incinerator is located at the rear of the furnace, and its rear arch is often short or there is no rear arch at all. The heat radiation generated by the combustion in the furnace is difficult to be reflected to the middle and front part of the grate. Therefore, its heating and drying ability for the newly entered garbage is poor. When the moisture content of the garbage is high and the calorific value is low, it may be difficult for the garbage to ignite autonomously. The central flow incinerator has a longer rear arch, which can reflect more radiant heat to the front of the grate, and has a stronger stable combustion ability, but its furnace space is smaller than that of the downstream type, and the combustion space is more concentrated. Its gas phase combustion is more intense than that of the downstream incinerator. In recent years, the calorific value of domestic garbage has been continuously increasing, which has put forward higher requirements for the operation and regulation level of the incinerator. Therefore, when designing a central flow incinerator, it is often necessary to consider more the regulating effect of the furnace structure and the air distribution scheme on the combustion conditions, so that the combustion conditions in the furnace have a higher degree of adjustability.

[0004] There is a central flow incinerator, such as Figure 1 As shown, the grate (1) is located at the bottom of the furnace and is divided into five levels. There is a certain height difference between the first and second levels and between the third and fourth levels. A feed port (2) is provided at the front end of the grate and a slag discharge port (3) is provided at the rear end. Both sides of the grate are refractory furnace walls (8). Two ignition burners (6) are provided on the front arch (4) of the furnace wall at the upper part of the furnace. An auxiliary burner (7) is provided on each of the side walls (9) on both sides. The entrance of the first flue (10) is located in the front middle part of the furnace. The water-cooled wall is arranged around the first flue (10) and extends to the middle part of the furnace wall along with the front arch (4), the rear arch (5) and the side wall (9). A secondary air duct (11) is provided at the lower part of the first flue. The secondary air duct of this central flow incinerator is arranged as shown in FIG. Figure 2As shown in the figure, a horizontal double tangential circle arrangement is adopted, with a tangential circle diameter of 2.5 to 3.5 meters. Eight secondary air ducts are arranged on the front and rear walls of the first flue of the boiler, for a total of 24 ducts, arranged in three layers. Eight secondary air ducts on each layer are arranged in a double tangential circle manner to form two circular cyclones after the air is discharged. It can be seen that the secondary air ducts are concentrated in the first flue, which has a limited regulating effect on the furnace combustion. In addition, there are a large number of air ducts, and the air volume control is complex. It is difficult to form an annular flow field when the combustion conditions change rapidly. In addition, the design of the rear arch reduces the radiant heat reflected from the combustion in the furnace to the front of the grate, which is not conducive to the drying, volatilization and ignition of the garbage entering the furnace.

[0005] How to optimize and improve the existing central flow incinerator to enhance the regulating ability of secondary air on the combustion in the furnace and make it easier for the newly input garbage to dry, release volatiles and ignite is an issue that needs attention. Summary of the invention

[0006] In view of the above problems, the present application provides a domestic waste incinerator and a furnace secondary air distribution control method to enhance the regulating ability of secondary air on combustion in the furnace and make the newly entered waste easier to dry, precipitate, volatilize and ignite.

[0007] In order to achieve the above objectives, the specific plan is proposed as follows:

[0008] A domestic waste incinerator comprises a furnace, a grate, an ignition burner, an auxiliary burner, a refractory furnace wall, a first flue, a water-cooled wall, a flame folding angle and a secondary air duct group;

[0009] The furnace comprises a front arch and a rear arch, the angle between the wall surface of the front arch and the horizontal is 25°, the angle between the wall surface of the rear arch and the horizontal is 35°, and the flame folding angle and one ignition burner are arranged on the rear arch;

[0010] The grate is located at the bottom of the furnace;

[0011] The refractory furnace walls are located on both sides of the grate;

[0012] One auxiliary burner is respectively installed on the side walls on both sides of the furnace;

[0013] The inlet of the first flue is located in the front middle part of the furnace, the water-cooled wall is arranged around the first flue, and the water-cooled wall extends to the middle part of the refractory furnace wall along with the front arch, the rear arch, the side wall and the flame bending angle;

[0014] The secondary air duct group is provided at the lower part of the first flue, and the air outlet of the secondary air duct group forms a double elliptical flow field in the first flue.

[0015] Optionally, the domestic waste incinerator further includes a rear arch secondary air duct;

[0016] A row of rear arch secondary air ducts is also arranged on the rear arch.

[0017] Optionally, the domestic waste incinerator further includes a front arch secondary air duct;

[0018] A row of front arch secondary air ducts is arranged on the front arch.

[0019] Optionally, the secondary air duct group includes 12 flue secondary air ducts;

[0020] Six flue secondary air ducts are arranged at the lower part of the front wall and the lower part of the rear wall of the first flue, and each flue secondary air duct has an inclination angle with the wall of the first flue. The air outlet of each flue secondary air duct makes the wind flow field formed in the first flue two ellipses with the center line of the flue wall of the first flue as the axis of symmetry.

[0021] Optionally, the six flue secondary air ducts at the lower part of the front wall of the first flue are external secondary air ducts that blow air outward from the center line of the flue wall, and the six flue secondary air ducts at the lower part of the rear wall of the first flue are internal secondary air ducts that blow air inward from the center line of the flue wall;

[0022] The 6 internal-blowing secondary air ducts include 2 inner internal-blowing secondary air ducts, 2 middle internal-blowing secondary air ducts and 2 outer internal-blowing secondary air ducts; the 6 external-blowing secondary air ducts include 2 inner external-blowing secondary air ducts, 2 middle external-blowing secondary air ducts and 2 outer external-blowing secondary air ducts;

[0023] The angle between each inner internal blowing secondary air duct and the center line of the flue wall is 8°;

[0024] The angle between each middle side inner blowing secondary air duct and the center line of the flue wall is 22°;

[0025] The angle between each outer inner-blowing secondary air duct and the center line of the flue wall is 33°;

[0026] The angle between each inner external secondary air duct and the center line of the flue wall is 35°;

[0027] The angle between each middle side external blowing secondary air duct and the center line of the flue wall is 24°;

[0028] The angle between each outer external blowing secondary air duct and the center line of the flue wall is 12°.

[0029] A furnace secondary air distribution control method is applied to the intelligent controller of the domestic waste incinerator as described above, wherein the secondary air duct group of the domestic waste incinerator includes 12 flue secondary air ducts, a plurality of temperature sensors are arranged on the wall and wall surface of the first flue, each flue secondary air duct is equipped with an angle adjuster, and each temperature sensor and each angle adjuster are connected to the intelligent controller;

[0030] The method includes:

[0031] When the combustion conditions change and the double elliptical flow field in the flue is destroyed, the intelligent controller uses the temperature distribution model to obtain the temperature distribution in the flue and the risk area of ​​over-temperature on the flue wall based on the temperature information monitored by each temperature sensor;

[0032] According to the risk area, the intelligent controller calls the flue secondary air angle adjustment strategy preset in the database to roughly adjust the angles of all flue secondary air ducts, and fine-adjusts the angle of each flue secondary air duct individually through the traversal method until a double elliptical flow field with a stability within the preset stability range is re-established to eliminate the risk of wall overheating, and the duct angle data with angle data values ​​within the preset angle data value range is updated into the database.

[0033] Optionally, the interior of the first flue of the domestic waste incinerator is divided into four secondary air duct areas according to the center line of the front and rear walls of the first flue and the center line of the flue wall, and each secondary air duct area contains 3 flue secondary air ducts;

[0034] The method further includes:

[0035] Acquire temperature data from each temperature sensor, and determine the overheated position of the wall according to the temperature data from each temperature sensor;

[0036] Determine the target secondary air duct area according to the overheated position of the wall;

[0037] Adjusting the angle adjusters of each flue secondary air duct in the target secondary air duct area so that each flue secondary air duct in the target secondary air duct area blows directly toward the overheated position of the wall surface;

[0038] Adjust the angle adjusters of the other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area so that the air outlet of each of the other flue secondary air ducts forms a circulating flow field with the air outlet of each flue secondary air duct in the target secondary air duct area.

[0039] Optionally, determining a target secondary air duct area according to the overheated wall position includes:

[0040] If the wall overheating position is located on the front wall of the first flue, two secondary air duct areas located on the rear wall of the first flue are determined as target secondary air duct areas;

[0041] If the wall overheating position is located on the rear wall of the first flue, two secondary air duct areas located on the front wall of the first flue are determined as target secondary air duct areas;

[0042] If the wall overheating position is located on the wall of the first flue, the symmetrical secondary air duct area of ​​the wall overheating position is determined as the target secondary air duct area, and the symmetrical secondary air duct area is a secondary air duct area that takes the center line of the front and rear walls as the axis of symmetry and is symmetrical to the secondary air duct area where the wall overheating position is located.

[0043] Optionally, adjusting the angle adjusters of other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area so that the air outlets of each of the other flue secondary air ducts and the air outlets of each flue secondary air duct in the target secondary air duct area form a circulation field, including:

[0044] When the wall overheating position is located at the front wall or the rear wall of the first flue, determining the area covered by the secondary air flow field formed by the air blowing of each flue secondary air duct in the target secondary air duct area at the wall overheating position;

[0045] For each other flue secondary air duct in the secondary air duct group except the flue secondary air duct in the target secondary air duct area, determine the blowing direction of the other flue secondary air duct that does not blow directly toward the area covered by the secondary air flow field, and based on the blowing direction of the other flue secondary air duct, adjust the angle adjuster of the other flue secondary air duct so that the air outlet of each other flue secondary air duct and the air outlet of each flue secondary air duct in the target secondary air duct area form a circulating flow field.

[0046] Optionally, adjusting the angle adjusters of other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area so that the air outlets of each of the other flue secondary air ducts and the air outlets of each flue secondary air duct in the target secondary air duct area form a circulation field, including:

[0047] When the wall overheating position is located on the wall of the first flue, determining the blowing angle of each flue secondary air duct in the target secondary air duct area;

[0048] Taking the center line of the flue wall as the axis of symmetry, determining a reverse blowing secondary air duct area symmetrical to the target secondary air duct area;

[0049] For each flue secondary air duct in the target secondary air duct area, taking the flue wall centerline as the symmetry axis, determining the blowing angle of the reverse blowing flue secondary air duct in the reverse blowing secondary air duct area that is symmetrical to the flue secondary air duct;

[0050] Taking the intersection of the wall where the target secondary air duct area is located and the center line of the flue wall as the target point, determining the blowing angle of each flue secondary air duct on the other wall of the wall where the target secondary air duct area is located as the angle at which the flue secondary air duct blows toward the target point;

[0051] Adjust the respective angle adjusters according to the blowing angles of each other flue secondary air duct in the secondary air duct group except the flue secondary air duct in the target secondary air duct area, so that the air outlet of each other flue secondary air duct and the air outlet of each flue secondary air duct in the target secondary air duct area form a circulating flow field.

[0052] With the help of the above-mentioned technical scheme, the secondary air duct of the flue of the domestic waste incinerator of the present application adopts a double elliptical arrangement, which has a stronger anti-interference ability than the double-tangent circle method. When the combustion conditions change frequently, it can still better increase the flue gas disturbance, improve the flow field uniformity and protect the wall surface from overheating. By increasing the inclination angle of the rear arch and increasing the flame deflection angle, the stable combustion effect of the furnace is improved, making it easier for newly-entered garbage to dry, precipitate volatiles and ignite, thereby enhancing the stable combustion ability of the incinerator. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0054] Figure 1 A schematic diagram of the structure of an existing central flow incinerator provided for this application;

[0055] Figure 2 A schematic diagram of the air duct layout of the secondary air duct of an existing central flow incinerator provided in this application;

[0056] Figure 3 A schematic diagram of the structure of a domestic waste incinerator provided in an embodiment of the present application;

[0057] Figure 4 A schematic diagram of an air duct arrangement of a secondary air duct of a flue of a domestic waste incinerator provided in an embodiment of the present application;

[0058] Figure 5A schematic diagram illustrating the center lines of the front and rear walls of the secondary air duct of the flue of a domestic waste incinerator provided in an embodiment of the present application, the center line of the flue wall, the secondary air duct area, and the area covered by the secondary air flow field;

[0059] Figure 6 A schematic diagram of a flow chart for realizing secondary air distribution control of flue provided in an embodiment of the present application. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0061] Figure 3 A schematic diagram of the structure of a domestic waste incinerator provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, the domestic waste incinerator may include:

[0062] Furnace, grate 1, ignition burner 6, auxiliary burner 7, refractory furnace wall 8, first flue 10, water-cooled wall, flame folding angle 11, secondary air duct group 12, front arch secondary air duct 13 and rear arch secondary air duct 14.

[0063] The furnace comprises a front arch 4 and a rear arch 5 .

[0064] The angle between the wall surface of the front arch 4 and the horizontal is 25°.

[0065] The angle between the wall surface of the rear arch 5 and the horizontal is 35°, and the rear arch 5 is provided with the flame deflection angle 11 and one ignition burner 6 .

[0066] It can be understood that by arranging the ignition burner 6 in the rear arch 5 of the furnace, due to the relatively open space of the rear arch 5, the arrangement position of the ignition burner 6 can more easily avoid other measuring points such as thermocouples and pressure measuring tubes, thereby reducing the interference of the flame of the ignition burner 6 on the measurement parameters, and at the same time reducing the interference of other flames on the flame monitoring system of the ignition burner 6 during the ignition process, so that each measurement data can more realistically reflect the combustion conditions in the furnace.

[0067] The grate 1 is located at the bottom of the furnace, a feed port 2 is provided at the front end of the grate, and a slag discharge port 3 is provided at the rear end of the grate.

[0068] Specifically, there can be a large vertical drop between the levels of the grate 1, and the impact force during the fall can be used to increase the crushing and turning effects of the garbage layer. There is no need to design a separate fire-stirring device. The combustion effect of the garbage layer is higher, and the garbage is better burned out. At the same time, the longitudinal length of the grate can be shortened to save initial investment costs and construction space.

[0069] The refractory furnace walls 8 are located on both sides of the grate 1 .

[0070] One auxiliary burner 7 is respectively installed on the side walls 9 on both sides of the furnace.

[0071] The entrance of the first flue 10 is located in the front middle part of the furnace. The first flue 10 is surrounded by the water-cooled wall, which extends to the middle part of the refractory furnace wall 8 along with the front arch 4, the rear arch 5, the side wall 9 and the flame deflection angle 11.

[0072] It can be understood that since the domestic waste incinerator is provided with a flame deflection angle 11 at the flue entrance, it can intercept a part of the radiant heat in the furnace and enhance the flow disturbance and combustion efficiency of the flue gas in the furnace, increase the temperature level in the furnace, and enable the garbage entering the furnace to achieve more stable autonomous ignition, combustion and burnout, thereby reducing the frequency of adjustment of the incinerator.

[0073] The secondary air duct group 12 is provided at the lower part of the first flue 10 , and the air outlet of the secondary air duct group 12 forms an elliptical air flow field in the first flue 10 .

[0074] Furthermore, a row of rear arch secondary air ducts 14 is also provided on the rear arch 5 .

[0075] Furthermore, a row of front arch secondary air ducts 13 is provided on the front arch 4 .

[0076] It is understandable that, since the secondary air of the domestic waste incinerator adopts a hierarchical arrangement scheme, there is a row of secondary air nozzles on the front arch 4 and the rear arch 5 of the furnace, which can play a role in separately adjusting the gas phase combustion in the furnace. Similarly, the secondary air in the flue can also separately adjust the flow field in the flue. When the calorific value of the garbage is high and the combustible content is high, the secondary air distribution volume of the furnace arch can be appropriately increased to allow more combustion to occur in the furnace, and then the flue secondary air is used to adjust the temperature of the flue gas in the flue, so that the combustion and flue temperature are adjusted separately, which significantly reduces the difficulty of regulating the combustion. When the calorific value of the garbage is low, while ensuring the autonomous ignition of the garbage entering the furnace, the secondary air volume of the arch can be appropriately reduced, and the secondary air volume of the flue can be increased, so that more combustible gases enter the first flue for combustion, so that the temperature level of the first flue 10 is maintained above 850°C required by the environmental protection index. Compared with the centralized arrangement of secondary air, the hierarchical arrangement can reduce the overall coupling effect of secondary air on the combustion conditions in the furnace, enhance the regulating ability and accuracy of secondary air on gas phase combustion and furnace temperature, simplify the control logic of the automatic control system, and improve the stability of the entire incineration system.

[0077] Furthermore, the secondary air duct group 12 includes 12 flue secondary air ducts, such as Figure 4 shown.

[0078] Among them, 6 flue secondary air ducts are arranged at the lower part of the front wall and the lower part of the rear wall of the first flue 10, and each flue secondary air duct has an inclination angle with the wall of the first flue 10. The air outlet of each flue secondary air duct makes the wind flow field formed in the first flue 10 two ellipses with the center line of the flue wall of the first flue 10 as the axis of symmetry.

[0079] Furthermore, the six flue secondary air ducts at the lower part of the front wall of the first flue 10 can be external blowing secondary air ducts that blow air outward from the center line of the flue wall, and the six flue secondary air ducts at the lower part of the rear wall of the first flue 10 can be internal blowing secondary air ducts that blow air inward from the center line of the flue wall.

[0080] Specifically, when the six flue secondary air ducts at the lower part of the front wall of the first flue 10 are externally-blown secondary air ducts that blow air outwardly from the center line of the flue wall, the six secondary air ducts at the lower part of the rear wall of the first flue 10 are internally-blown secondary air ducts that blow air inwardly from the center line of the flue wall. When the six flue secondary air ducts at the lower part of the front wall of the first flue 10 are internally-blown secondary air ducts that blow air outwardly from the center line of the flue wall, the six flue secondary air ducts at the lower part of the rear wall of the first flue 10 are externally-blown secondary air ducts that blow air inwardly from the center line of the flue wall.

[0081] Among them, the 6 internal blowing secondary air ducts include 2 inner internal blowing secondary air ducts, 2 middle internal blowing secondary air ducts and 2 outer internal blowing secondary air ducts, and the 6 external blowing secondary air ducts include 2 inner external blowing secondary air ducts, 2 middle external blowing secondary air ducts and 2 outer external blowing secondary air ducts.

[0082] Specifically, the angle between each inner internal blowing secondary air duct and the center line of the flue wall can be 8°.

[0083] The angle between each middle inner-blowing secondary air duct and the center line of the flue wall can be 22°.

[0084] The angle between each outer inner-blowing secondary air duct and the center line of the flue wall can be 33°.

[0085] The angle between each inner external-blowing secondary air duct and the center line of the flue wall can be 35°.

[0086] The angle between each middle side external blowing secondary air duct and the center line of the flue wall can be 24°.

[0087] The angle between each outer external blowing secondary air duct and the center line of the flue wall can be 12°.

[0088] It can be understood that by arranging the secondary air duct of the flue into a double ellipse, it has a stronger anti-interference ability than the double-tangent circle method. When the combustion conditions change frequently, it can still better increase the flue gas disturbance, improve the flow field uniformity and protect the wall from overheating.

[0089] Next, the usage of the domestic waste incinerator of the present application is introduced.

[0090] Combination Figure 3 , domestic garbage is transported to the grate 1 through the feed port 2, and moves to the slag outlet 3 under the mechanical movement of the grate 1. The vents on the grate 1 will send out high-temperature primary air to heat the garbage layer. In this process, the garbage will go through the stages of drying, volatile precipitation, ignition, combustion, and burnout. The solid slag after burnout is discharged from the incinerator through the slag outlet. The volatile matter precipitated from the garbage is mostly combustible gas, and its combustion in the incinerator is called gas phase combustion or secondary combustion. The corresponding solid combustibles in the garbage layer on the grate are called solid phase combustion or primary combustion. The combustible gas is burned in the gas phase space in the furnace under the mixing and combustion assistance of the primary air and the arch secondary air. A part of the combustible gas that has not yet burned in the furnace flows into the first flue 10 with the flue gas and burns out under the combustion assistance of the flue secondary air. Part of the heat released by the gas phase and solid phase combustion is absorbed by the boiler working fluid through the heat exchange surfaces such as the water-cooled wall and the superheater to generate steam, and the steam drives the steam engine to generate electricity.

[0091] When the automatic control system is put into operation, the control logic adjusts the load of the unit by measuring the steam production of the boiler. When the steam production is lower than the set value, the feed amount of garbage is increased, otherwise it is reduced.

[0092] The domestic waste incinerator provided in this embodiment has a double elliptical arrangement of the flue secondary air duct, which has a stronger anti-interference ability than the double-tangent circle method. It can still better increase the flue gas disturbance, improve the flow field uniformity and protect the wall from overheating when the combustion conditions change frequently. The flame deflection angle is increased by increasing the inclination angle of the rear arch, thereby improving the stable combustion effect of the furnace, making it easier for newly-introduced garbage to dry, precipitate volatiles and ignite, thereby enhancing the stable combustion ability of the incinerator.

[0093] Considering that the high-temperature flue gas generated by burning garbage flows inside the first flue 10 of the domestic waste incinerator, it may stick to the wall or cause overheating. Based on this, the present application provides a flue secondary air distribution control method, which can be applied to the intelligent controller of the domestic waste incinerator.

[0094] Specifically, the method may include the following steps:

[0095] S1. When the combustion conditions change and the double elliptical flow field in the furnace is destroyed, the intelligent controller uses the temperature distribution model to derive the temperature distribution in the furnace and the risk area of ​​overheating on the furnace wall based on the temperature information monitored by each temperature sensor.

[0096] S2. According to the risk area, the intelligent controller calls the preset flue secondary air angle adjustment strategy in the database to roughly adjust the angles of all flue secondary air ducts.

[0097] S3. Fine-tune the angle of each flue secondary air duct individually through the traversal method until a double elliptical flow field with a stability within a preset stability range is re-established to eliminate the risk of wall overheating, and update the air duct angle data with angle data values ​​within the preset angle data value range into the database.

[0098] It is understandable that when fine-tuning the angle of each flue secondary air duct, the double elliptical flow field needs to be sufficiently stable, and the air duct angle data is more effective in eliminating the risk of wall overheating.

[0099] In some embodiments of the present application, a detailed control strategy for a furnace secondary air distribution control method is provided. In the control strategy, the interior of the first flue 10 of the domestic waste incinerator is divided into four secondary air duct areas according to the center lines of the front and rear walls of the first flue 10 and the center lines of the flue walls. Each secondary air duct area contains three flue secondary air ducts. The walls and walls of the first flue 10 are provided with multiple temperature sensors. Each flue secondary air duct is equipped with an angle adjuster. Each temperature sensor and each angle adjuster are connected to an intelligent controller. Then, the intelligent controller can control the angle adjusters equipped on each flue secondary air duct. The center lines of the front and rear walls, the center lines of the flue walls, and the secondary air duct areas are as follows: Figure 5 As shown, the secondary air duct areas A, B, C and D are respectively divided by the center lines of the front and rear walls and the center line of the flue wall, and the secondary air duct areas A, B, C and D contain 3 flue secondary air ducts respectively.

[0100] The specific implementation process of the furnace secondary air distribution control method through the above control strategy is as follows: Figure 6 As shown, this may include:

[0101] Step S110: Acquire temperature data from each temperature sensor, and determine the overheated position of the wall according to the temperature data from each temperature sensor.

[0102] Specifically, when the highest temperature data among the temperature data acquired from each temperature sensor is greater than the preset temperature, it can be determined that the position of the temperature sensor corresponding to the highest temperature data is the overheated position of the wall.

[0103] Step S120: determining a target secondary air duct area according to the overheated position of the wall.

[0104] Specifically, according to the different overheating positions of the wall, the target secondary air duct area can be divided into the following three situations:

[0105] First, if the overheated wall position is located on the front wall of the first flue 10, two secondary air duct areas located on the rear wall of the first flue 10 are determined as target secondary air duct areas.

[0106] like Figure 5 As shown, if the wall overheating position is located on the front wall, then the target secondary air duct area can be determined to be secondary air duct area B and secondary air duct area D.

[0107] Second, if the wall overheating position is located on the rear wall of the first flue 10, two secondary air duct areas located on the front wall of the first flue 10 are determined as target secondary air duct areas.

[0108] like Figure 5As shown, if the wall overheating position is located on the rear wall, then the target secondary air duct area can be determined as secondary air duct area A and secondary air duct area C.

[0109] Third, if the wall overheating position is not located on the front wall or the rear wall, but on the wall of the first flue 10, the symmetrical secondary air duct area of ​​the wall overheating position is determined as the target secondary air duct area.

[0110] Among them, the symmetrical secondary air duct area is a secondary air duct area that takes the center line of the front and rear walls as the symmetry axis and is symmetrical to the secondary air duct area where the overheating position of the wall is located.

[0111] like Figure 5 As shown, if the overheating position of the wall is located on the wall of the secondary air duct area A, then the target secondary air duct area can be determined to be the secondary air duct area B. If the overheating position of the wall is located on the wall of the secondary air duct area B, then the target secondary air duct area can be determined to be the secondary air duct area A. If the overheating position of the wall is located on the wall of the secondary air duct area C, then the target secondary air duct area can be determined to be the secondary air duct area D. If the overheating position of the wall is located on the wall of the secondary air duct area D, then the target secondary air duct area can be determined to be the secondary air duct area C.

[0112] Step S130, adjusting the angle adjusters of each flue secondary air duct in the target secondary air duct area so that each flue secondary air duct in the target secondary air duct area blows directly toward the overheated position of the wall.

[0113] like Figure 5 As shown, when the overheated position of the wall is located at the intersection of the front wall and the center line of the front and rear walls, all the flue secondary air ducts on the rear wall are aligned with the intersection to blow directly to the overheated position of the wall.

[0114] Step S140, adjusting the angle adjusters of other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area, so that the air outlet of each of the other flue secondary air ducts and the air outlet of each flue secondary air duct in the target secondary air duct area form a circulating flow field.

[0115] Specifically, according to the specific location of the overheated position on the wall, the process of adjusting the angle adjuster of the secondary air duct of other flues can be divided into the following two cases:

[0116] 1) S1411. When the wall overheating position is located at the front wall or the rear wall of the first flue, determine the secondary air flow field coverage area of ​​the wall overheating position formed by the air blowing of each flue secondary air duct in the target secondary air duct area.

[0117] Specifically, the secondary wind flow field covers an area such as Figure 5As shown, when the wall overheating position is located at the intersection of the front wall and the center line of the front and rear walls, all the flue secondary air ducts on the rear wall are aligned with the intersection, forming a secondary air flow field coverage area as shown by the dotted triangle.

[0118] S1412. For each other flue secondary air duct in the secondary air duct group except the flue secondary air duct in the target secondary air duct area, determine the blowing direction of the other flue secondary air duct that does not blow directly toward the area covered by the secondary air flow field, and based on the blowing direction of the other flue secondary air duct, adjust the angle adjusters of the other flue secondary air ducts so that the air outlet of each other flue secondary air duct and the air outlet of each flue secondary air duct in the target secondary air duct area form a circulating flow field.

[0119] Examples include Figure 5 When the wall overheating position is located on the front wall, all the flue secondary air ducts on the rear wall are the flue secondary air ducts in the target secondary air duct area, and all the flue secondary air ducts on the front wall are other flue secondary air ducts. Since the flue secondary air ducts on the rear wall blow directly to the wall overheating position on the front wall, the other flue secondary air ducts on the front wall can be adjusted to an angle that does not blow directly to the area covered by the secondary air flow field under the condition that a circulation field needs to be formed. Figure 5 The inner side external blowing secondary air duct at the lower part of the middle front wall is 35° outward, the middle side external blowing secondary air duct is 24° outward, and the outer side external blowing secondary air duct is 12° outward.

[0120] 2) S1421. When the wall overheating position is located on the wall of the first flue, determine the blowing angle of each flue secondary air duct in the target secondary air duct area.

[0121] For example, when the wall overheating position is located at Figure 5 On the wall surface of the secondary air duct area B shown, the secondary air duct area A is the target secondary air duct area, and the directions of the three flue secondary air ducts in the secondary air duct area A are determined accordingly.

[0122] S1422. Taking the center line of the flue wall as the axis of symmetry, determine a reverse blowing secondary air duct area that is symmetrical to the target secondary air duct area.

[0123] For example, when the wall overheating position is located at Figure 5 On the wall surface of the secondary air duct area B shown, the secondary air duct area A is the target secondary air duct area, and the secondary air duct area C is the reverse blowing secondary air duct area.

[0124] S1423. For each flue secondary air duct in the target secondary air duct area, taking the center line of the flue wall as the axis of symmetry, determine the blowing angle of the reverse-blowing flue secondary air duct in the reverse-blowing secondary air duct area that is symmetrical to the flue secondary air duct.

[0125] For example, when the wall overheating position is located at Figure 5 On the wall of the secondary air duct area B shown, assuming that the angle directions of the three flue secondary air ducts in the secondary air duct area A are respectively 35° for the inner external blowing secondary air duct, 24° for the middle external blowing secondary air duct, and 12° for the outer external blowing secondary air duct, then the angle directions of the three secondary air ducts in the secondary air duct area C are respectively 35° for the inner external blowing secondary air duct, 24° for the middle external blowing secondary air duct, and 12° for the outer external blowing secondary air duct.

[0126] S1424. Taking the intersection of the wall where the target secondary air duct area is located and the center line of the flue wall as the target point, determine the blowing angle of each flue secondary air duct on the other wall of the wall where the target secondary air duct area is located as the angle at which the flue secondary air duct blows toward the target point.

[0127] For example, when the wall overheating position is located at Figure 5 On the wall of the secondary air duct area B shown in the figure, after determining the blowing angle of each flue secondary air duct at the lower part of the front wall, the blowing angle of each flue secondary air duct on the rear wall can be determined as the angle blowing toward the target point.

[0128] S1425. Adjust the respective angle adjusters according to the blowing angles of the other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area, so that the air outlets of the other flue secondary air ducts and the air outlets of the flue secondary air ducts in the target secondary air duct area form a circulating flow field.

[0129] The furnace secondary air distribution control method provided in the present embodiment obtains the temperature data of each temperature sensor, and determines the wall overheating position according to the temperature data of each temperature sensor, determines the target secondary air duct area according to the wall overheating position, adjusts the angle adjusters of each flue secondary air duct in the target secondary air duct area so that each flue secondary air duct in the target secondary air duct area blows directly toward the wall overheating position, and adjusts the angle adjusters of other flue secondary air ducts in the secondary air duct group except the flue secondary air duct in the target secondary air duct area so that the air outlet of each of the other flue secondary air ducts forms a circulation field with the air outlet of each flue secondary air duct in the target secondary air duct area, effectively confines the high-temperature flue gas in the middle of the flue, so that the wall and wall in the first flue 10 will not overheat, and overheating is effectively prevented.

[0130] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0131] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can refer to each other.

[0132] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A domestic waste incinerator, characterized in that: It includes furnace, grate, ignition burner, auxiliary burner, refractory furnace wall, first flue, water-cooled wall, flame folding angle and secondary air duct group; The furnace comprises a front arch and a rear arch, the angle between the wall surface of the front arch and the horizontal is 25°, the angle between the wall surface of the rear arch and the horizontal is 35°, and the flame folding angle and one ignition burner are arranged on the rear arch; The grate is located at the bottom of the furnace; The refractory furnace walls are located on both sides of the grate; One auxiliary burner is respectively installed on the side walls on both sides of the furnace; The inlet of the first flue is located in the front middle part of the furnace, the water-cooled wall is arranged around the first flue, and the water-cooled wall extends to the middle part of the refractory furnace wall along with the front arch, the rear arch, the side wall and the flame bending angle; The secondary air duct group is provided at the lower part of the first flue, and the air discharged from the secondary air duct group forms an elliptical air flow field in the first flue; The secondary air duct group includes 12 flue secondary air ducts; Six flue secondary air ducts are arranged at the lower part of the front wall and the lower part of the rear wall of the first flue, each flue secondary air duct has an inclination angle with the wall surface of the first flue, and the air discharge of each flue secondary air duct makes the air flow field formed in the first flue form two ellipses with the center line of the flue wall of the first flue as the symmetry axis; The domestic waste incinerator further comprises a rear arch secondary air duct and a front arch secondary air duct; The rear arch is also provided with a row of rear arch secondary air ducts; A row of front arch secondary air ducts is arranged on the front arch; The six flue secondary air ducts at the lower part of the front wall of the first flue are external secondary air ducts that blow air outward from the center line of the flue wall, and the six flue secondary air ducts at the lower part of the rear wall of the first flue are internal secondary air ducts that blow air inward from the center line of the flue wall; The 6 internal-blowing secondary air ducts include 2 inner internal-blowing secondary air ducts, 2 middle internal-blowing secondary air ducts and 2 outer internal-blowing secondary air ducts, and the 6 external-blowing secondary air ducts include 2 inner external-blowing secondary air ducts, 2 middle external-blowing secondary air ducts and 2 outer external-blowing secondary air ducts.

2. The domestic waste incinerator according to claim 1, characterized in that: The angle between each inner internal blowing secondary air duct and the center line of the flue wall is 8°; The angle between each middle side inner blowing secondary air duct and the center line of the flue wall is 22°; The angle between each outer inner-blowing secondary air duct and the center line of the flue wall is 33°; The angle between each inner external secondary air duct and the center line of the flue wall is 35°; The angle between each middle side external blowing secondary air duct and the center line of the flue wall is 24°; The angle between each outer external blowing secondary air duct and the center line of the flue wall is 12°.

3. A furnace secondary air distribution control method, characterized in that: Applicable to the domestic waste incinerator as claimed in claim 1, the method comprises: an intelligent controller; The secondary air duct group of the domestic waste incinerator includes 12 flue secondary air ducts, the wall and wall surface of the first flue are provided with a plurality of temperature sensors, each flue secondary air duct is equipped with an angle adjuster, and each temperature sensor and each angle adjuster are connected to the intelligent controller; When the combustion conditions change and the double elliptical flow field in the furnace is destroyed, the intelligent controller uses the temperature distribution model to obtain the temperature distribution in the furnace and the risk area of ​​over-temperature on the furnace wall based on the temperature information monitored by each temperature sensor; According to the risk area, the intelligent controller calls the flue secondary air angle adjustment strategy preset in the database to roughly adjust the angles of all flue secondary air ducts, and fine-adjusts the angle of each flue secondary air duct individually through the traversal method until a double elliptical flow field with a stability within the preset stability range is re-established to eliminate the risk of wall overheating, and the duct angle data with angle data values ​​within the preset angle data value range is updated into the database.

4. The method according to claim 3, characterized in that The interior of the first flue of the domestic waste incinerator is divided into four secondary air duct areas according to the center line of the front and rear walls of the first flue and the center line of the flue wall, and each secondary air duct area contains 3 flue secondary air ducts; The method further includes: Acquire temperature data from each temperature sensor, and determine the overheated position of the wall according to the temperature data from each temperature sensor; Determine the target secondary air duct area according to the overheated position of the wall; Adjusting the angle adjusters of each flue secondary air duct in the target secondary air duct area so that each flue secondary air duct in the target secondary air duct area blows directly toward the overheated position of the wall surface; Adjust the angle adjusters of the other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area so that the air outlet of each of the other flue secondary air ducts and the air outlet of each flue secondary air duct in the target secondary air duct area form a double circulation field.

5. The method according to claim 4, characterized in that According to the overheated position of the wall, the target secondary air duct area is determined, including: If the wall overheating position is located on the front wall of the first flue, two secondary air duct areas located on the rear wall of the first flue are determined as target secondary air duct areas; If the wall overheating position is located on the rear wall of the first flue, two secondary air duct areas located on the front wall of the first flue are determined as target secondary air duct areas; If the wall overheating position is located on the wall of the first flue, the symmetrical secondary air duct area of ​​the wall overheating position is determined as the target secondary air duct area, and the symmetrical secondary air duct area is a secondary air duct area that takes the center line of the front and rear walls as the axis of symmetry and is symmetrical to the secondary air duct area where the wall overheating position is located.

6. The method according to claim 5, characterized in that Adjusting the angle adjusters of other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area so that the air outlets of each of the other flue secondary air ducts and the air outlets of each flue secondary air duct in the target secondary air duct area form a circulation field, including: When the wall overheating position is located at the front wall or the rear wall of the first flue, determining the area covered by the secondary air flow field formed by the air blowing of each flue secondary air duct in the target secondary air duct area at the wall overheating position; For each other flue secondary air duct in the secondary air duct group except the flue secondary air duct in the target secondary air duct area, determine the blowing direction of the other flue secondary air duct that does not blow directly toward the area covered by the secondary air flow field, and based on the blowing direction of the other flue secondary air duct, adjust the angle adjuster of the other flue secondary air duct so that the air outlet of each other flue secondary air duct and the air outlet of each flue secondary air duct in the target secondary air duct area form a circulating flow field.

7. The method according to claim 5, characterized in that Adjusting the angle adjusters of other flue secondary air ducts in the secondary air duct group except the flue secondary air ducts in the target secondary air duct area so that the air outlets of each of the other flue secondary air ducts and the air outlets of each flue secondary air duct in the target secondary air duct area form a circulation field, including: When the wall overheating position is located on the wall of the first flue, determining the blowing angle of each flue secondary air duct in the target secondary air duct area; Taking the center line of the flue wall as the axis of symmetry, determining a reverse blowing secondary air duct area symmetrical to the target secondary air duct area; For each flue secondary air duct in the target secondary air duct area, taking the flue wall centerline as the symmetry axis, determining the blowing angle of the reverse blowing flue secondary air duct in the reverse blowing secondary air duct area that is symmetrical to the flue secondary air duct; Taking the intersection of the wall where the target secondary air duct area is located and the center line of the flue wall as the target point, determining the blowing angle of each flue secondary air duct on the other wall of the wall where the target secondary air duct area is located as the angle at which the flue secondary air duct blows toward the target point; Adjust the respective angle adjusters according to the blowing angles of each other flue secondary air duct in the secondary air duct group except the flue secondary air duct in the target secondary air duct area, so that the air outlet of each other flue secondary air duct and the air outlet of each flue secondary air duct in the target secondary air duct area form a circulating flow field.

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