Flameless combustion furnace with preheating assisted by combustion and operation method

Abstract

The invention discloses a flameless combustion furnace with preheating assisted by combustion and an operation method, and relates to the technical field of combustion equipment.The flameless combustion furnace comprises a furnace body, a combustion airflow distribution nozzle and an ignition device, and a combustion cavity and a preheating cooling cavity which have a dividing wall heat exchange relation are formed in the furnace body; the combustion cavity is provided with an air jet orifice, a fuel nozzle and a tail gas exhaust port, the fuel nozzle is provided with a fuel jet orifice, the air jet orifice and the fuel nozzle are respectively arranged on two opposite inner sides of the combustion cavity, the tail gas exhaust port and the air jet orifice are positioned on the same side of the combustion cavity, and the preheating cooling cavity is provided with an air orifice and a first fuel orifice; the combustion airflow distribution nozzle is configured to control the fuel input channel to be communicated with the first fuel spraying hole or the fuel jet spraying hole; the ignition device is arranged in the preheating cooling cavity. By means of the design of the preheating cooling cavity, the combustion furnace can automatically preheat the wall face in the starting stage, and quick and effective preparation conditions are provided for stable flameless combustion.

Description

Technical Field

[0001] The invention relates to the technical field of combustion equipment, and in particular to a flameless combustion furnace with combustion-assisted preheating and an operation method thereof. Background Art

[0002] Flameless combustion technology is widely used in industrial production due to its advantages such as high combustion efficiency and low pollutant emissions. However, traditional flameless combustion furnaces have some shortcomings: on the one hand, the startup time is long and the preheating process is slow, which affects production efficiency; on the other hand, the furnace wall protection measures are insufficient during the combustion process, which is prone to overheating and damage, shortening the service life of the combustion furnace. Summary of the invention The object of the present invention is to provide a flameless combustion furnace with combustion-assisted preheating and an operating method to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.

[0003] The technical solutions adopted to solve the above technical problems are: The present invention provides a flameless combustion furnace with combustion-assisted preheating, comprising: A furnace body, wherein a combustion chamber and a preheating and cooling chamber having a partition wall heat exchange relationship are provided inside, the preheating and cooling chamber is wrapped around the outside of the combustion chamber, the combustion chamber is provided with at least one air jet port, a fuel nozzle and an exhaust gas discharge port, the fuel nozzle is provided with at least one fuel jet nozzle hole, the air jet port is communicated with the preheating and cooling chamber, the air jet port and the fuel nozzle are respectively provided on two opposite inner sides of the combustion chamber, the exhaust gas discharge port and the air jet port are located on the same side of the combustion chamber, and the preheating and cooling chamber is provided with at least one air nozzle hole and at least one first fuel nozzle hole; A combustion air flow distribution nozzle, provided with a fuel input channel, wherein the combustion air flow distribution nozzle is configured to control the fuel input channel to be connected to the first fuel injection hole or the fuel jet injection hole; An ignition device is arranged in the preheating and cooling chamber.

[0004] The flameless combustion furnace of the present invention has the following beneficial effects: When the flameless combustion furnace is cold started, the fuel input channel is controlled to be connected to the first fuel nozzle through the combustion air flow distribution nozzle, so that the fuel passes into the preheating cooling chamber, and at the same time, the air is sprayed into the preheating cooling chamber through the air nozzle, so that the fuel and air are mixed in the preheating cooling chamber, and then the fuel in the preheating cooling chamber is ignited and burned by the ignition device, and the heat generated is used to preheat the wall of the combustion chamber. At this time, the burning exhaust gas is discharged outward through the air jet port, the combustion chamber and the exhaust gas discharge port in sequence. When the wall of the combustion chamber is heated to the target temperature of flameless combustion, the fuel input channel is controlled to be connected to the fuel jet nozzle through the combustion air flow distribution nozzle, and the fuel is sprayed into the combustion chamber through the fuel jet nozzle through the fuel nozzle, and the air is sprayed into the preheating cooling chamber through the air nozzle, and then enters the combustion chamber through the air jet port, so that the fuel and air are counter-mixed and burned in the combustion chamber to quickly start the flameless combustion furnace. At this time, only air is introduced into the preheating and cooling chamber, and the air flows through the preheated wall surface, absorbs heat and then sprays into the combustion chamber, which plays a role in protecting the combustion chamber wall surface, preventing it from being directly impacted by the high-temperature flame, and realizing the function of cooling the wall surface. At the same time, the air in the preheating and cooling chamber returns the absorbed heat to the combustion chamber, improves the utilization rate of heat, maintains the high-temperature environment in the combustion chamber, and ensures the continuous flameless combustion. Through the design of the preheating and cooling chamber, the present invention enables the combustion furnace to preheat the wall surface by itself during the startup phase, without the need for additional preheating equipment or energy input, simplifies the system structure, improves the preheating efficiency, shortens the preheating time, and provides fast and effective preparation conditions for the stable flameless combustion.

[0005] During the flameless combustion stage, air is injected into the combustion chamber through the air jet port and mixed with the fuel sprayed from the fuel nozzle to form a uniform combustion flow field. The air jet port and the exhaust gas exhaust port are located on the same side of the combustion chamber. The exhaust gas is in the opposite direction to the high-velocity air jet, which increases the residence time of the combustion airflow. The air is first fully mixed with the combustion exhaust gas to reduce the oxygen concentration before mixing with the fuel, which effectively reduces the combustion rate and better maintains the flameless combustion state. The fuel nozzle is located on the other side of the combustion chamber and can effectively mix with the air on the other side of the combustion chamber.

[0006] As a further improvement of the above technical solution, the combustion air flow distribution nozzle includes a nozzle seat and a fuel input pipeline, the nozzle seat is arranged on the furnace wall of the furnace body, the nozzle seat is provided with a rotating channel connected to the fuel nozzle, one end of the fuel input pipeline is rotatably installed on the rotating channel, the fuel input channel is formed inside the fuel input pipeline, one end of the fuel input pipeline is provided with a fuel inlet, and the other end is eccentrically provided with at least one third fuel nozzle, the end of the fuel nozzle connected to the rotating channel is eccentrically provided with at least one fourth fuel nozzle, the fourth fuel nozzle is connected to the fuel jet nozzle, at least one first fuel nozzle is arranged on the outer peripheral wall of the rotating channel, at least one second fuel nozzle is arranged on the outer peripheral wall of the fuel input pipeline, the first fuel nozzle and the second fuel nozzle are located at the same axial position, and the fuel input pipeline is configured to control the connection and disconnection between the first fuel nozzle and the second fuel nozzle, and control the connection and disconnection between the third fuel nozzle and the fourth fuel nozzle by rotation.

[0007] As a further improvement of the above technical solution, a first leaf baffle is provided at the end of the fuel nozzle connected to the rotating channel, the fourth fuel nozzle is provided at the first leaf baffle, a second leaf baffle is provided at the end of the fuel input pipe close to the fuel nozzle, and the third fuel nozzle is provided at the second leaf baffle.

[0008] As a further improvement of the above technical solution, a first rotation limit portion is provided at the center position of the first leaf baffle, and a second rotation limit portion is provided at the center position of the second leaf baffle, and the second rotation limit portion is rotationally connected and cooperated with the first rotation limit portion.

[0009] As a further improvement of the above technical solution, a plurality of the first fuel spray holes and a plurality of the second fuel spray holes are respectively provided, and the plurality of the first fuel spray holes are annularly spaced on the outer peripheral wall of the rotating channel, and the plurality of the second fuel spray holes are annularly spaced on the outer peripheral wall of the fuel input pipe.

[0010] As a further improvement of the above technical solution, the nozzle seat is provided with an air pre-supply chamber, and the air pre-supply chamber is wrapped around the center line on the outside of the fuel input pipe. There are multiple air spray holes, and the multiple air spray holes are annularly spaced on the outer wall of the nozzle seat and are connected to the air pre-supply chamber. The air pre-supply chamber is provided with an air inlet.

[0011] As a further improvement of the above technical solution, the preheating and cooling chamber includes an ignition chamber, a catalytic chamber and a convergent injection chamber which are connected in sequence, the ignition chamber and the convergent injection chamber are respectively located at two ends of the combustion chamber, the catalytic chamber is located on the outer peripheral side of the combustion chamber, the air nozzle and the first fuel nozzle are respectively connected to the ignition chamber, the air jet port is connected to the convergent injection chamber, the ignition device is arranged in the ignition chamber, the catalytic chamber is provided with a plurality of heat-conducting fins extending from the ignition chamber to the convergent injection chamber, the plurality of heat-conducting fins are arranged in a ring-shaped interval, the heat-conducting fins are connected to the outer peripheral wall of the combustion chamber and the inner peripheral wall of the catalytic chamber, and the surface of the heat-conducting fins is provided with a catalytic combustion catalyst.

[0012] As a further improvement of the above technical solution, the fuel nozzle and the exhaust gas discharge port are located on the center line of the combustion chamber, a plurality of air jet ports are provided, and the plurality of air jet ports are arranged in a ring-shaped manner on the side of the inner end of the exhaust gas discharge port, and the injection direction of the air jet ports is arranged along the inner wall of the combustion chamber. A guide slope is provided at one end of the combustion chamber close to the exhaust gas discharge port, and a plurality of fuel jet nozzles are provided, and the plurality of fuel jet nozzles are distributed on the outer peripheral wall of the fuel nozzle.

[0013] As a further improvement of the above technical solution, the ignition device is provided with a spark plug ignition part and a spark plug terminal, the spark plug ignition part is arranged on the outside of the furnace body, the spark plug terminal is arranged in the ignition chamber, and the distance between the spark plug terminal and the wall of the ignition chamber is between 3 mm and 10 mm.

[0014] In addition, the present invention also proposes an operating method, which is applicable to the flameless combustion furnace, and the operating method comprises: Controlling the fuel input channel to communicate with the first fuel injection hole; Passing fuel into the preheating and cooling chamber, and spraying air into the preheating and cooling chamber through the air spray holes, so that the fuel and the air are mixed in the preheating and cooling chamber; The ignition device ignites and burns the fuel in the preheating and cooling chamber to heat the combustion chamber; When the cavity wall of the combustion cavity reaches a preset temperature, controlling the fuel input channel to be connected to the fuel jet nozzle; The fuel is sprayed into the combustion chamber, and the air is sprayed into the preheating and cooling chamber through the air spray hole, and then enters the combustion chamber through the air jet port, so that the fuel and air are mixed and burned to start the flameless combustion furnace.

[0015] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments; Figure 1 is a cross-sectional view of an embodiment of the flameless combustion furnace provided by the present invention; Figure 2 is a schematic diagram of an embodiment of a combustion air flow distribution nozzle provided by the present invention; Figure 3 is a schematic diagram of an embodiment of a fuel nozzle provided by the present invention; Figure 4 is a schematic diagram of an embodiment of a fuel input pipeline provided by the present invention; Figure 5 is a control flow chart of an embodiment of the operation method provided by the present invention; Figure Number: Furnace body 100; combustion chamber 110; air jet port 111; fuel nozzle 112; fuel jet nozzle hole 1121; fourth fuel nozzle hole 1122; first lobed baffle 1123; first rotation limiter 1124; tail gas discharge port 113; preheating and cooling chamber 120; air nozzle hole 121; first fuel nozzle hole 122; ignition chamber 123; catalytic chamber 124; converging injection chamber 125; heat conducting fins 126; Combustion air flow distribution nozzle 200; fuel input channel 210; nozzle seat 220; rotation channel 221; air pre-supply chamber 222; upper rotating sleeve 223; air inlet 2221; fuel input pipeline 230; fuel inlet 231; third fuel injection hole 232; second fuel injection hole 233; second leaf baffle 234; second rotation limiter 235; control handle 236; lower rotating sleeve 237; Ignition device 300 ; spark plug ignition portion 310 ; spark plug terminal 320 . DETAILED DESCRIPTION

[0017] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0018] In the description of the present invention, it should be understood that descriptions involving orientation, such as orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0019] In the description of the present invention, "a plurality" means more than two. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0020] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0021] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described below are only some embodiments of the present invention, not all embodiments.

[0022] like Figures 1 to 4 As shown, a flameless combustion furnace with combustion-assisted preheating of the present invention comprises: a furnace body 100 , a combustion air flow distribution nozzle 200 and an ignition device 300 .

[0023] like Figure 1 As shown, a combustion chamber 110 and a preheating and cooling chamber 120 having a partition heat exchange relationship are provided inside the furnace body 100, and the preheating and cooling chamber 120 is wrapped around the outside of the combustion chamber 110. It can be understood that the furnace body 100 of this embodiment includes an inner wall body and an outer wall body, the combustion chamber 110 is formed in the inner wall body, and the preheating and cooling chamber 120 is formed between the inner wall body and the outer wall body. The furnace body 100 of this embodiment is vertically arranged, and the outer shape of the furnace body 100 is cylindrical, and the center line of the furnace body 100 extends in the up and down directions. In some other embodiments, the furnace body 100 may be other shapes, and the furnace body 100 may be horizontally arranged or extended in other directions.

[0024] like Figure 1As shown, the combustion chamber 110 is provided with at least one air jet port 111, a fuel nozzle 112 and an exhaust gas discharge port 113, the fuel nozzle 112 is provided with at least one fuel jet nozzle 1121 connected to the combustion chamber 110, the air jet port 111 is connected to the preheating and cooling chamber 120, the air jet port 111 connects the preheating and cooling chamber 120 and the combustion chamber 110, the air jet port 111 and the fuel nozzle 112 are respectively arranged on two opposite inner sides of the combustion chamber 110, and the air jet port 111 of this embodiment is arranged in the combustion chamber 110, and the fuel nozzle 112 is arranged on the lower side of the combustion chamber 110, and the exhaust gas exhaust port 113 and the air jet port 111 are located on the same side of the combustion chamber 110, that is, the exhaust gas exhaust port 113 is also arranged on the upper side of the combustion chamber 110, and the preheating and cooling chamber 120 is provided with at least one air nozzle 121 and at least one first fuel nozzle 122, wherein the air nozzle 121 is used to spray external air into the preheating and cooling chamber 120, and the first fuel nozzle 122 is used to spray external fuel into the preheating and cooling chamber 120.

[0025] The combustion air flow distribution nozzle 200 of the present invention is provided with a fuel input channel 210, and the fuel input channel 210 is used to connect with an external fuel supply system to realize the input of fuel. The combustion air flow distribution nozzle 200 is configured to control the fuel input channel 210 to be connected to the first fuel nozzle 122 or the fuel jet nozzle 1121. It can be understood that the fuel input channel 210 can be switched to be connected with the first fuel nozzle 122 alone. At this time, the fuel in the fuel input channel 210 is sprayed into the preheating cooling chamber 120 through the first fuel nozzle 122, or the fuel input channel 210 is switched to be connected with the fuel jet nozzle 1121. At this time, the fuel in the fuel input channel 210 is sprayed into the combustion chamber 110 through the fuel jet nozzle 1121.

[0026] The ignition device 300 of this embodiment is disposed in the preheating cooling chamber 120 , and the ignition device 300 is used to ignite a mixture of fuel and air in the preheating cooling chamber 120 .

[0027] When the flameless combustion furnace is cold started, the fuel input channel 210 is controlled to be connected to the first fuel injection hole 122 through the combustion air flow distribution nozzle 200, so that the fuel is passed into the preheating cooling chamber 120, and the air is injected into the preheating cooling chamber 120 through the air injection hole 121, so that the fuel and the air are mixed in the preheating cooling chamber 120, and then the fuel in the preheating cooling chamber 120 is ignited and burned by the ignition device 300, and the heat generated is used to preheat the wall surface of the combustion chamber 110. At this time, the exhaust gas of the combustion passes through the air injection port 111, the combustion chamber 110 and the exhaust gas of the combustion chamber 110 in sequence. The exhaust gas is discharged outward from the exhaust port 113. When the wall of the combustion chamber 110 is heated to the target temperature of flameless combustion, the fuel input channel 210 is controlled to be connected to the fuel jet nozzle 1121 through the combustion air flow distribution nozzle 200. The fuel is sprayed into the combustion chamber 110 through the fuel nozzle 112 through the fuel jet nozzle 1121, and the air is sprayed into the preheating and cooling chamber 120 through the air nozzle 121, and then enters the combustion chamber 110 through the air jet port 111, so that the fuel and air are counter-mixed and burned in the combustion chamber 110 to quickly start the flameless combustion furnace. At this time, only air is passed into the preheating and cooling chamber 120. The air flows through the preheated wall, absorbs heat and is sprayed into the combustion chamber 110, which plays a role in protecting the wall of the combustion chamber 110 and preventing it from being directly impacted by the high-temperature flame, thereby realizing the function of cooling the wall. At the same time, the air in the preheating cooling chamber 120 will return the absorbed heat to the combustion chamber 110, thereby improving the utilization rate of heat, maintaining the high temperature environment in the combustion chamber 110, and ensuring the continuous flameless combustion. Through the design of the preheating cooling chamber 120, the combustion furnace can preheat the wall surface by itself during the startup phase without the need for additional preheating equipment or energy input, thereby simplifying the system structure, improving the preheating efficiency, shortening the preheating time, and providing fast and effective preparation conditions for the stable implementation of flameless combustion.

[0028] During the flameless combustion stage, air is injected into the combustion chamber 110 through the air jet port 111 and mixed with the fuel sprayed from the fuel nozzle 112 to form a uniform combustion flow field. The air jet port 111 and the exhaust gas outlet 113 are located on the same side of the combustion chamber 110. The exhaust gas is in the opposite direction to the high-velocity air jet, which increases the residence time of the combustion airflow. The air is first fully mixed with the combustion exhaust gas to reduce the oxygen concentration before mixing with the fuel, which effectively reduces the combustion rate and better maintains the flameless combustion state. The fuel nozzle 112 is located on the other side of the combustion chamber 110 and can effectively mix with the air on the other side of the combustion chamber 110.

[0029] In some other embodiments, the combustion air flow distribution nozzle 200 may use two control valves to achieve the switching of fuel delivery, that is, a control valve is set between the fuel input channel 210 and the first fuel nozzle 122, and a control valve is set between the fuel input channel 210 and the fuel jet nozzle 1121, and the fuel delivery switching is achieved by controlling the on and off of the two control valves.

[0030] In order to realize the flexible switching of the gas path of the combustion furnace in different combustion stages and facilitate operation, Figure 1 and Figure 2 As shown, the combustion air flow distribution nozzle 200 includes a nozzle seat 220 and a fuel input pipe 230. The nozzle seat 220 is arranged between the inner wall and the outer wall of the furnace body 100 and is located on the lower side of the furnace body 100. The nozzle seat 220 is provided with a rotating channel 221 connected to the fuel nozzle 112. The rotating channel 221 of this embodiment is vertically arranged, and the upper end of the rotating channel 221 is connected to the fuel nozzle 112. In some other embodiments, the rotating channel 221 may extend in other directions.

[0031] The fuel input pipeline 230 is also arranged vertically. In some other embodiments, the fuel input pipeline 230 may extend in other directions. The upper end of the fuel input pipeline 230 is rotatably mounted on the rotating channel 221. The fuel input channel 210 is formed inside the fuel input pipeline 230. The lower end of the fuel input pipeline 230 is provided with a fuel inlet 231. Figure 4 As shown, at least one third fuel injection hole 232 is eccentrically disposed at the upper end of the fuel input pipe 230. Figure 3 As shown, at least one fourth fuel nozzle 1122 is eccentrically provided at one end of the fuel nozzle 112 connected to the rotating channel 221, and the fourth fuel nozzle 1122 is connected to the fuel jet nozzle 1121. By rotating the fuel input pipe 230, the third fuel nozzle 232 and the fourth fuel nozzle 1122 are overlapped or misaligned to realize the connection and disconnection of the fuel input channel 210 and the fuel jet nozzle 1121.

[0032] like Figure 2 As shown, the first fuel spray hole 122 of the present embodiment is arranged on the outer peripheral wall of the rotating channel 221, and the outer peripheral wall of the fuel input pipe 230 is provided with at least one second fuel spray hole 233. The first fuel spray hole 122 and the second fuel spray hole 233 are located at the same axial position. By rotating the fuel input pipe 230, the second fuel spray hole 233 and the first fuel spray hole 122 are overlapped or misaligned to realize the connection and disconnection of the fuel input channel 210 and the first fuel spray hole 122.

[0033] Furthermore, in this embodiment, the connection between the first fuel nozzle 122 and the second fuel nozzle 233 and the connection between the third fuel nozzle 232 and the fourth fuel nozzle 1122 can be controlled by rotating the fuel input pipe 230. The operation is simple and only needs to be done by rotating the fuel input pipe 230.

[0034] Furthermore, if Figure 3 and Figure 4As shown, the lower end of the fuel nozzle 112 of this embodiment is provided with a first leaf baffle 1123, and the upper end of the fuel input pipe 230 is provided with a second leaf baffle 234. The second leaf baffle 234 and the first leaf baffle 1123 are sealed and fitted together, and a plurality of fourth fuel nozzles 1122 and a plurality of third fuel nozzles 232 are respectively provided. The plurality of fourth fuel nozzles 1122 are arranged in a ring-shaped manner on the first leaf baffle 1123, and the plurality of third fuel nozzles 232 are arranged in a ring-shaped manner on the second leaf baffle 234.

[0035] The design of the first blade baffle 1123 and the second blade baffle 234 enables fuel diversion, and can accurately control the amount of fuel entering the combustion chamber 110 according to different combustion requirements, thereby ensuring the stability and efficiency of combustion.

[0036] A first rotation limit portion 1124 is provided at the center position of the first leaf baffle 1123, and a second rotation limit portion 235 is provided at the center position of the second leaf baffle 234. The second rotation limit portion 235 is rotatably connected and cooperated with the first rotation limit portion 1124. The first rotation limit portion 1124 and the second rotation limit portion 235 are respectively a limit protrusion and a limit hole structure, so that the first leaf baffle 1123 and the second leaf baffle 234 will not shift during rotation, ensuring safety, and also forming an effective connection between the fuel nozzle 112 and the fuel input pipe 230, so that the flow of fuel can be precisely controlled.

[0037] In this embodiment, a plurality of first fuel spray holes 122 and a plurality of second fuel spray holes 233 are respectively provided, and a plurality of first fuel spray holes 122 are annularly spaced on the outer peripheral wall of the rotating channel 221, and a plurality of second fuel spray holes 233 are annularly spaced on the outer peripheral wall of the fuel input pipe 230 to increase the amount of fuel entering the preheating cooling chamber 120, wherein the second fuel spray hole 233 and the third fuel spray hole 232 are staggered in the axial direction, and when the second fuel spray hole 233 coincides with the first fuel spray hole 122, the third fuel spray hole 232 is staggered with the fourth fuel spray hole 1122.

[0038] The plurality of first fuel injection holes 122 can allow the fuel to be injected into the preheating and cooling chamber 120 from the center to the periphery.

[0039] like Figure 2As shown, the nozzle holder 220 of this embodiment is further provided with an air pre-supply chamber 222, which is wrapped around the center line on the outside of the fuel input pipe 230, and a plurality of air spray holes 121 are provided, and the plurality of air spray holes 121 are arranged in annular intervals on the outer peripheral wall of the nozzle holder 220 and are connected to the air pre-supply chamber 222, and the air pre-supply chamber 222 is provided with an air inlet 2221. The air pre-supply chamber 222 enables air to be uniformly sprayed into the preheating and cooling chamber 120 through the plurality of air spray holes 121. In the preheating stage and the flameless combustion stage, air enters the air pre-supply chamber 222 through the air inlet 2221, and then enters the preheating and cooling chamber 120 through the plurality of air spray holes 121.

[0040] Furthermore, the plurality of air spray holes 121 can allow air to be sprayed from the center to the periphery into the preheating and cooling chamber 120 .

[0041] The outer wall at the lower end of the fuel input pipe 230 of the present embodiment is provided with a control handle 236, and the fuel input pipe 230 is driven to rotate by the control handle 236. By rotating the control handle 236 in different directions, the opening and closing state between the first leaf baffle 1123 and the second leaf baffle 234 can be controlled, thereby realizing the connection and closure between the third fuel nozzle 232 and the fourth fuel nozzle 1122, and the connection and closure between the second fuel nozzle 233 and the first fuel nozzle 122. This design makes the fuel distribution more flexible, and can accurately control the fuel supply flow channel according to different combustion stages, thereby ensuring the stability and efficiency of combustion.

[0042] In order to improve the rotation stability of the fuel input pipeline 230, the air pre-supply chamber 222 of this embodiment is provided with an upper rotating sleeve 223, and the fuel input pipeline 230 is provided with a lower rotating sleeve 237. The upper rotating sleeve 223 is rotatably connected with the lower rotating sleeve 237. This rotating sleeve connection method enables the air pre-supply chamber 222 and the fuel input pipeline 230 to rotate flexibly, and it is convenient to directly rotate the fuel input pipeline 230 by rotating the control handle 236.

[0043] Furthermore, if Figure 1As shown, the preheating cooling chamber 120 of the present embodiment includes an ignition chamber 123, a catalytic chamber 124 and a confluence injection chamber 125 which are connected in sequence. The confluence injection chamber 125 and the ignition chamber 123 are respectively located at the upper end and the lower end of the combustion chamber 110, and the catalytic chamber 124 is located on the outer peripheral side of the combustion chamber 110. A plurality of air nozzles 121 and a plurality of first fuel nozzles 122 are respectively connected to the ignition chamber 123, and the air jet port 111 is connected to the confluence injection chamber 125. The ignition device 300 is arranged in the ignition chamber 123. In the preheating stage, the fuel enters the fuel input pipe 230 through the fuel inlet 231, and then passes through the fuel inlet 231. The first fuel injection hole 122 enters the ignition chamber, and the air enters the air pre-supply chamber 222 through the air inlet 2221, and then enters the ignition chamber through the air injection hole 121. The two are evenly mixed in the ignition chamber, and ignited by the ignition device 300 for preheating and combustion, and then flows into the catalytic chamber 124 to preheat the outer wall of the combustion chamber 110, and then flows into the converging injection chamber 125, and enters the combustion chamber 110 through the air jet port 111. The exhaust gas after combustion flows into the combustion chamber 110 through the air jet port 111, which heats the inner wall on the one hand, and provides a large amount of exhaust gas after combustion for the combustion chamber 110 on the other hand, creating an environment for flameless combustion. In the flameless combustion stage, the air passes through the ignition chamber 123, the catalytic chamber 124 and the converging injection chamber 125 in turn to preheat and cool the inner wall. The air carrying heat is sprayed into the combustion chamber 110 again through the air jet port 111, which not only cools the wall surface, but also makes full use of the cooling air to avoid waste.

[0044] The catalytic chamber 124 of the present embodiment is provided with a plurality of heat-conducting fins 126 extending from the ignition chamber 123 to the converging injection chamber 125. The plurality of heat-conducting fins 126 are arranged in a ring-shaped interval. The heat-conducting fins 126 are connected to the outer peripheral wall of the combustion chamber 110 and the inner peripheral wall of the catalytic chamber 124. The surface of the heat-conducting fins 126 is provided with a catalytic combustion catalyst. The heat-conducting fins 126 can improve the overall structural strength of the furnace body 100 and increase the heat exchange area, thereby improving the heating efficiency in the preheating stage and the cooling effect in the flameless combustion stage. The catalytic combustion catalyst reduces the combustion temperature of the fuel, so that the fuel can be fully burned at a lower temperature, thereby improving the combustion efficiency, reducing the generation of unburned residues, rapidly increasing the furnace wall temperature, and greatly shortening the time required for the combustion chamber 110 to reach the starting temperature, so that the combustion furnace can quickly enter the flameless combustion state while controlling the combustion temperature.

[0045] like Figure 1As shown, the fuel nozzle 112 and the exhaust gas discharge port 113 of this embodiment are located on the center line of the combustion chamber 110, and a plurality of air jet ports 111 are provided. The plurality of air jet ports 111 are arranged in a ring-shaped manner on the outer side surface of the inner end of the exhaust gas discharge port 113. The injection direction of the air jet port 111 is arranged along the inner wall of the combustion chamber 110. A guide slope is provided on the upper part of the combustion chamber 110. A plurality of fuel jet nozzles 1121 are provided. The plurality of fuel jet nozzles 1121 are distributed on the outer peripheral wall of the fuel nozzle 112. During use, fuel is sprayed into the combustion chamber 110 from the bottom through the fuel nozzle 112, and air is sprayed into the combustion chamber 110 from the top along the inner wall surface through the air jet ports 111. The air flows along the wall surface and is input into the lower side of the combustion chamber 110, where it is mixed with the fuel sprayed from the plurality of fuel jet nozzles 1121 on the lower side to form a uniform combustion flow field. The tail gas is located on the upper side of the combustion chamber 110, and the exhaust direction is upward, which is opposite to the direction of the high-velocity air jet, which increases the residence time of the combustion airflow. The air jet port 111 is arranged circumferentially along the center line of the tail gas discharge port 113, so that the air is evenly jetted along the inner wall surface and distributed to the outside of the combustion chamber 110. At this time, the high-concentration oxygen is away from the fuel nozzle 112 located on the lower side of the center. The air is first fully mixed with the combustion tail gas, and then mixed with the fuel after reducing the oxygen concentration, which effectively reduces the combustion rate and better maintains the flameless combustion state. The fuel nozzle 112 is located on the lower side of the combustion chamber 110 and can effectively mix with the air at the bottom of the combustion chamber 110. The inner wall wraps the combustion chamber 110, so that the combustion airflow forms an air mass, further increasing the residence time of the combustion airflow and stabilizing the flameless combustion.

[0046] The ignition device 300 of this embodiment uses a spark plug. During the operation of the combustion furnace, the structural design and installation position of the spark plug have an important influence on the ignition effect and combustion stability.

[0047] The ignition device 300 of this embodiment is provided with a spark plug ignition portion 310 and a spark plug terminal 320. The spark plug ignition portion 310 is provided on the outside of the furnace body 100, and the spark plug terminal 320 is provided in the ignition chamber 123, so that the spark plug can effectively generate sparks inside the ignition chamber to ignite the mixture of fuel and air. The distance between the spark plug terminal 320 and the wall of the ignition chamber 123 is between 3 mm and 10 mm. This distance range can ensure that the spark generated by the spark plug has sufficient energy, while avoiding ignition failure or incomplete combustion caused by too close or too far distance.

[0048] In addition, the present invention also provides an operating method, which is applicable to the above-mentioned flameless combustion furnace, such as Figure 5 As shown, the operating method of this embodiment includes: Step S100: Control the fuel input channel 210 to be connected to the first fuel injection hole 122; Step S200: Passing fuel into the preheating cooling chamber 120, and spraying air into the preheating cooling chamber 120 through the air spray hole 121, so that the fuel and the air are mixed in the preheating cooling chamber 120; Step S300: igniting and burning the fuel in the preheating cooling chamber 120 through the ignition device 300 to heat the combustion chamber 110; Step S400: When the cavity wall of the combustion cavity 110 reaches a preset temperature, the fuel input channel 210 is controlled to be connected to the fuel jet nozzle 1121; Step S500: The fuel is sprayed into the combustion chamber 110, and the air is sprayed into the preheating and cooling chamber 120 through the air nozzle 121, and then enters the combustion chamber 110 through the air jet port 111, so that the fuel and air are mixed and burned to start the flameless combustion furnace.

[0049] In step S100 , during the ignition preheating stage, the fuel input pipe 230 is rotated by rotating the control handle 236 so that the second fuel injection hole 233 overlaps with the first fuel injection hole 122 to achieve communication between the fuel input channel 210 and the first fuel injection hole 122 .

[0050] In step S200 and step S300, fuel enters the fuel input pipe 230 through the fuel inlet 231, and then enters the ignition chamber through the first fuel nozzle 122. Air enters the air pre-supply chamber 222 through the air inlet 2221, and then enters the ignition chamber through the air nozzle 121. The two are evenly mixed in the ignition chamber and ignited by the ignition device 300 for preheating and combustion. Then, the fuel flows into the catalytic chamber 124 to preheat the outer wall of the combustion chamber 110, and then flows into the converging injection chamber 125 and enters the combustion chamber 110 through the air jet port 111. The exhaust gas after combustion flows into the combustion chamber 110 through the air jet port 111, which heats the inner wall on the one hand, and provides a large amount of exhaust gas after combustion to the combustion chamber 110 on the other hand, creating an environment for flameless combustion.

[0051] In step S400 and step S500, the fuel input pipe 230 is driven to rotate by rotating the control handle 236 so that the third fuel nozzle 232 coincides with the fourth fuel nozzle 1122 to achieve communication between the fuel input channel 210 and the fuel jet nozzle 1121. The fuel is sprayed into the combustion chamber 110 through the fuel nozzle 112 via the fuel jet nozzle 1121, and the air is sprayed into the preheating and cooling chamber 120 through the air nozzle 121, and then enters the combustion chamber 110 through the air jet port 111, so that the fuel and air are mixed and burned to start the flameless combustion furnace.

[0052] During the operation of the combustion furnace, the above control method can realize the rapid start-up and stable combustion of the combustion furnace. Under cold start conditions, by igniting the ignition chamber, catalytic combustion is realized to heat the inner wall provided with heat-conducting fins 126 and coated with catalytic combustion catalyst, so that the target temperature of flameless combustion can be quickly reached, and the start-up time can be shortened. By turning the control handle 236, the first fuel nozzle 122 is closed, and the fourth fuel nozzle 1122 is opened. The fuel is sprayed into the combustion chamber 110 through the fuel nozzle 112 through the fuel jet nozzle 1121, and the air is sprayed into the preheating cooling chamber 120 through the air nozzle 121, and then enters the combustion chamber 110 through the air jet port 111, so that the air can effectively control the wall temperature, and then return the absorbed heat to the combustion chamber 110 again, effectively starting the flameless combustion furnace.

[0053] The flameless combustion furnace of this embodiment can be applied to the following places: On-vehicle small burner: The present invention is a flameless burner for catalytic combustion assisted preheating suitable for on-vehicle environments. It is compact and easy to install in a dedicated equipment compartment of a vehicle. Lightweight and high-temperature resistant materials are used, and the outer wall has good heat insulation properties to ensure that the vehicle interior will not be damaged by the operation of the burner. The preheating cooling chamber 120 is adjacent to the combustion chamber 110, and is equipped with an appropriate amount of heat-conducting fins 126 inside, and is coated with an efficient catalytic combustion catalyst to accelerate the preheating process and maintain a stable combustion temperature. The combustion airflow distribution nozzle 200 integrates an automatic control system, which can intelligently adjust the fuel-air mixing ratio according to the vehicle's operating status and external environmental conditions.

[0054] The small vehicle-mounted burner can provide a stable heat source while the vehicle is driving, such as heating the vehicle-mounted decomposition equipment or heating the interior of the vehicle. Compared with traditional vehicle-mounted heating equipment, its startup time is shortened by about 25%, the combustion efficiency is increased by 20%, and due to the use of flameless combustion technology, it runs more quietly, with less vibration, and will not interfere with the vehicle's electronic equipment, significantly improving the comfort and safety of use.

[0055] Industrial furnace burner: The present invention effectively reduces the demand for high temperature resistant materials through the synergistic effect of the preheating cooling chamber 120 and the inner wall. The preheating cooling chamber 120 uses catalytic combustion to quickly heat the inner wall during the ignition stage, and cools the inner wall through air flow during the combustion stage, reducing the direct impact of high temperature on the inner wall and extending the service life. This design allows the inner wall to use lower cost materials instead of relying on expensive high temperature resistant alloys. In addition, due to the design of the preheating cooling chamber 120, the service life of the furnace is extended, and the product quality will be significantly improved due to more uniform and stable combustion.

[0056] Waste incinerator: The present invention is suitable for use in waste incinerators, and its equipment structure includes a larger combustion chamber 110 and a preheating and cooling chamber 120 of equivalent volume. The inner wall of the combustion chamber 110 is made of ordinary heat-resistant steel, and the outer wall is made of insulation material. Heat-conducting fins 126 are arranged inside the preheating and cooling chamber 120 and coated with a catalyst. The combustion air flow distribution nozzle 200 adopts an automatic control system to adapt to the fluctuations in fuel composition and flow rate during the waste incineration process. The present invention uses the special design of the preheating and cooling chamber 120 and the inner wall to achieve cooling by air flowing through the inner wall, thereby reducing the demand for expensive high-temperature resistant materials. The inner wall can meet the use requirements by using ordinary heat-resistant steel, which reduces the manufacturing cost of the equipment. At the same time, the automatic control system can adjust the combustion conditions in real time according to the actual situation during the waste incineration process, thereby improving the combustion efficiency and environmental protection performance.

[0057] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0058] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A flameless combustion furnace with combustion-assisted preheating, characterized in that: include: A furnace body, wherein a combustion chamber and a preheating and cooling chamber having a partition wall heat exchange relationship are provided inside, the preheating and cooling chamber is wrapped around the outside of the combustion chamber, the combustion chamber is provided with at least one air jet port, a fuel nozzle and an exhaust gas discharge port, the fuel nozzle is provided with at least one fuel jet nozzle hole, the air jet port is communicated with the preheating and cooling chamber, the air jet port and the fuel nozzle are respectively provided on two opposite inner sides of the combustion chamber, the exhaust gas discharge port and the air jet port are located on the same side of the combustion chamber, and the preheating and cooling chamber is provided with at least one air nozzle hole and at least one first fuel nozzle hole; A combustion air flow distribution nozzle, provided with a fuel input channel, wherein the combustion air flow distribution nozzle is configured to control the fuel input channel to be connected to the first fuel injection hole or the fuel jet injection hole; An ignition device is arranged in the preheating and cooling chamber.

2. The flameless combustion furnace according to claim 1, characterized in that: The combustion air flow distribution nozzle includes a nozzle seat and a fuel input pipeline, the nozzle seat is arranged on the furnace wall of the furnace body, the nozzle seat is provided with a rotating channel connected to the fuel nozzle, one end of the fuel input pipeline is rotatably installed on the rotating channel, the fuel input channel is formed inside the fuel input pipeline, one end of the fuel input pipeline is provided with a fuel inlet, and the other end is eccentrically provided with at least one third fuel nozzle hole, the end of the fuel nozzle connected to the rotating channel is eccentrically provided with at least one fourth fuel nozzle hole, the fourth fuel nozzle hole is connected with the fuel jet nozzle, at least one first fuel nozzle hole is arranged on the outer peripheral wall of the rotating channel, at least one second fuel nozzle hole is arranged on the outer peripheral wall of the fuel input pipeline, the first fuel nozzle hole and the second fuel nozzle hole are located at the same axial position, and the fuel input pipeline is configured to control the connection and disconnection between the first fuel nozzle hole and the second fuel nozzle hole, and control the connection and disconnection between the third fuel nozzle hole and the fourth fuel nozzle hole by rotation.

3. The flameless combustion furnace according to claim 2, characterized in that: A first leaf baffle is provided at one end of the fuel nozzle connected to the rotating channel, the fourth fuel nozzle is provided at the first leaf baffle, a second leaf baffle is provided at one end of the fuel input pipe close to the fuel nozzle, and the third fuel nozzle is provided at the second leaf baffle.

4. The flameless combustion furnace according to claim 3, characterized in that: A first rotation limiting portion is provided at the center position of the first leaf baffle, and a second rotation limiting portion is provided at the center position of the second leaf baffle. The second rotation limiting portion is rotationally connected and cooperated with the first rotation limiting portion.

5. The flameless combustion furnace according to claim 3, characterized in that: There are a plurality of the first fuel injection holes and a plurality of the second fuel injection holes, respectively. The plurality of the first fuel injection holes are arranged at annular intervals on the outer peripheral wall of the rotating channel, and the plurality of the second fuel injection holes are arranged at annular intervals on the outer peripheral wall of the fuel input pipe.

6. The flameless combustion furnace according to claim 2, characterized in that: The nozzle seat is provided with an air pre-supply chamber, and the air pre-supply chamber is wrapped around the center line on the outside of the fuel input pipe. There are multiple air spray holes, and the multiple air spray holes are annularly spaced on the outer wall of the nozzle seat and are connected to the air pre-supply chamber. The air pre-supply chamber is provided with an air inlet.

7. The flameless combustion furnace according to any one of claims 1 to 6, characterized in that: The preheating and cooling chamber includes an ignition chamber, a catalytic chamber and a convergent injection chamber which are connected in sequence. The ignition chamber and the convergent injection chamber are respectively located at two ends of the combustion chamber, and the catalytic chamber is located on the outer peripheral side of the combustion chamber. The air nozzle and the first fuel nozzle are respectively connected to the ignition chamber, and the air jet port is connected to the convergent injection chamber. The ignition device is arranged in the ignition chamber. The catalytic chamber is provided with a plurality of heat-conducting fins extending from the ignition chamber to the convergent injection chamber. The plurality of heat-conducting fins are arranged in a ring-shaped interval. The heat-conducting fins are connected to the outer peripheral wall of the combustion chamber and the inner peripheral wall of the catalytic chamber, and the surface of the heat-conducting fins is provided with a catalytic combustion catalyst.

8. The flameless combustion furnace according to claim 7, characterized in that: The fuel nozzle and the exhaust gas discharge port are located on the center line of the combustion chamber. There are multiple air jet ports, and the multiple air jet ports are arranged in a ring-shaped manner on the side of the inner end of the exhaust gas discharge port. The injection direction of the air jet ports is arranged along the inner wall of the combustion chamber. A guide slope is provided at one end of the combustion chamber close to the exhaust gas discharge port. There are multiple fuel jet nozzles, and the multiple fuel jet nozzles are distributed on the outer peripheral wall of the fuel nozzle.

9. The flameless combustion furnace according to claim 7, characterized in that: The ignition device is provided with a spark plug ignition part and a spark plug terminal. The spark plug ignition part is arranged outside the furnace body, and the spark plug terminal is arranged in the ignition chamber. The distance between the spark plug terminal and the wall of the ignition chamber is between 3 mm and 10 mm.

10. An operating method, characterized in that: It is applicable to the flameless combustion furnace according to any one of claims 1 to 9, and the operation method comprises: Controlling the fuel input channel to communicate with the first fuel injection hole; Passing fuel into the preheating and cooling chamber, and spraying air into the preheating and cooling chamber through the air spray holes, so that the fuel and the air are mixed in the preheating and cooling chamber; The ignition device ignites and burns the fuel in the preheating and cooling chamber to heat the combustion chamber; When the cavity wall of the combustion cavity reaches a preset temperature, controlling the fuel input channel to be connected to the fuel jet nozzle; The fuel is sprayed into the combustion chamber, and the air is sprayed into the preheating and cooling chamber through the air spray hole, and then enters the combustion chamber through the air jet port, so that the fuel and air are mixed and burned to start the flameless combustion furnace.

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