Boiler with ultralow oxynitride emission

Abstract

The utility model relates to the technical field of boilers, and discloses a boiler with ultralow oxynitride emission, which comprises a boiler main body, a heat exchange chamber, a first induced draft fan and a chimney which are sequentially connected, the output end of the first induced draft fan is communicated with the chimney through an arranged connecting pipe, an oxygen content detection device is arranged on the connecting pipe, and the oxygen content detection device is connected with the heat exchange chamber. An electric air door is further installed on the connecting pipe, a second induced draft fan is installed on the other side of the electric air door through a pipeline, the output end of the second induced draft fan communicates with a hearth of the boiler body through a pipeline, and waste smoke in the connecting pipe is discharged into the boiler body again through the second induced draft fan, so that the oxygen concentration of fuel combustion is reduced, and the combustion efficiency is improved. According to the invention, the waste flue gas is discharged from the chimney, so that the chemical generation of oxynitride (NoX) is reduced, the purpose of ultralow emission is achieved, the waste flue gas is discharged from the chimney, and the problem of environmental pollution caused by the discharged flue gas in the prior art is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a boiler technical field especially relates to a kind of boiler of ultra-low nitrogen oxide compound emission. BACKGROUND

[0002] The principle of the main fuel combustion of the boiler is that the combustible in the fuel and the oxidant in the air undergo a high-speed chemical reaction of heat and light, and release a large amount of heat and light energy. In the combustion furnace, under the action of high temperature, the nitrogen element (N) in the fuel and the nitrogen (N2) and oxygen (O2) in the air undergo a chemical reaction to produce nitrogen oxide (NoX) pollutants.

[0003] However, in the traditional main system of the boiler, the combustion of the fuel on the grate produces a large amount of nitrogen oxide, and the oxygen content in the final exhaust gas is about 12%, which pollutes the environment and does not achieve the purpose of environmental protection. INVENTION CONTENTS

[0004] The utility model discloses a kind of boiler of ultra-low nitrogen oxide compound emission to solve the problems in prior art.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0006] A kind of boiler of ultra-low nitrogen oxide compound emission, including sequentially connected boiler main body, heat exchange chamber, first induced draft fan and chimney, the output end of the first induced draft fan and chimney are connected by the communication of the connecting pipe being set, oxygen content detection device is installed on the connecting pipe, electric damper is also installed on the connecting pipe, the other side of electric damper is installed with second induced draft fan by pipeline, the output end of the second induced draft fan is connected with the furnace of boiler main body by pipeline.

[0007] Preferably, the signal output end of the oxygen content detection device is installed with a control processor by wire, and the signal output end of the control processor is connected with the electric damper by wire.

[0008] Preferably, the boiler main body includes a furnace body, a grate located at the bottom of the furnace body, a third induced draft fan connected with the grate, a fuel feeding pipe obliquely arranged on one side of the grate and connected with the inner cavity of the grate, and a first flue gas outlet opened on one side of the furnace body, the first flue gas outlet is connected with the heat exchange chamber and the first induced draft fan by pipeline, a flue gas inlet is opened on one side of the furnace body, and the output end of the second induced draft fan is connected with the inner cavity of the furnace body through the flue gas inlet.

[0009] Preferably, the heat exchange chamber is an air preheater.

[0010] Compared with the prior art, the utility model has the advantages that:

[0011] The utility model discloses a boiler main part is set up, and the fuel is placed in the boiler main part and is combusted, and the boiler main part is heated, and the first induced draft fan is set up, can exhaust the waste flue gas from the boiler main part, makes the waste flue gas pass through the heat exchange chamber, and then the waste flue gas is entered into the chimney through the connecting pipe, and then is discharged, and the oxygen content detection device is set up, can detect the oxygen content in the waste flue gas, to control the opening of electric damper, through the second induced draft fan, the waste flue gas in the connecting pipe is discharged into the boiler main part again, thereby reducing the oxygen concentration of fuel combustion, thereby reducing the chemical production of nitrogen oxide (NoX), and achieving the purpose of ultra-low emission. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 The utility model discloses a kind of composition schematic diagram of boiler of ultra-low nitrogen oxide compound emission proposed.

[0013] In the drawing: 1, furnace body;2, first flue gas outlet;3, heat exchange chamber;4, first induced draft fan;5, connecting pipe;6, chimney;7, oxygen content detection device;8, electric damper;9, second induced draft fan;11, grate;12, fuel feeding pipe;14, third induced draft fan;15, flue gas inlet;16, steam outlet. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments.

[0015] Referring to Figure 1 A kind of boiler of ultra-low nitrogen oxide compound emission, including sequentially connected boiler main body, heat exchange chamber 3, first induced draft fan 4 and chimney 6, the first induced draft fan 4 output and chimney 6 are connected by the connecting pipe 5 of setting, the connecting pipe 5 is equipped with oxygen content detection device 7, the connecting pipe 5 is also equipped with electric damper 8, the other side of electric damper 8 is equipped with second induced draft fan 9 by pipeline, the second induced draft fan 9 output is connected by pipeline with boiler main body hearth.

[0016] The oxygen content detection device 7 is oxygen content detector, and the oxygen content detector is mainly based on electrochemical sensor. When gas passes through the sensor, oxygen will react with the electrode in the sensor. This reaction is usually the reduction or oxidation process of oxygen molecules on the electrode. The chemical reaction causes an electric current between the electrodes, and the strength of the current is proportional to the concentration of oxygen. The current signal is converted into a readable concentration value, which is displayed on the display screen of the instrument. The present oxygen content detector is prior art and will not be described in detail here.

[0017] The electric damper 8 includes a valve installed on the connecting pipe 5 and an electric motor used to drive the valve. The electric motor opens the valve, allowing the output end of the second induced draft fan 9 to connect with the inside of the connecting pipe 5, so that the waste flue gas with excessive oxygen content in the connecting pipe 5 can be discharged back into the combustion chamber for re-combustion.

[0018] In operation, fuel is placed inside the boiler body for combustion to heat the boiler. A first induced draft fan 4 draws waste gas from the boiler body, through the heat exchange chamber 3, and then through the connecting pipe 5 into the chimney 6 before being discharged. Traditional boilers typically emit flue gas with an oxygen content of around 12%. An oxygen content detection device 7 detects the oxygen content in the waste gas, allowing adjustment of the electric damper 8 based on the oxygen content. A second induced draft fan 9 then re-exposes the waste gas from the connecting pipe 5 into the boiler body, allowing the boiler to continue consuming the oxygen in the waste gas. Ultimately, this controls the oxygen content of the flue gas entering the chimney to be ≤8%, and the nitrogen oxide (NOx) level to be ≤100 mg / Nm3, achieving ultra-low emissions.

[0019] Furthermore, the signal output terminal of the oxygen content detection device 7 is equipped with a control processor via a wire. The signal output terminal of the control processor is connected to the electric damper 8 via a wire. The control processor can control the electric damper 8 to open based on the oxygen content of the exhaust gas detected by the oxygen content detection device 7 (generally, the oxygen content of the exhaust gas is around 12%), so that the second induced draft fan 9 can reintroduce the exhaust gas into the combustion chamber, consume the oxygen in the exhaust gas, and achieve the purpose of ultra-low emissions.

[0020] Furthermore, the boiler body includes a furnace body 1, a grate 11 located at the bottom of the furnace body 1, a third induced draft fan 14 connected to the grate 11, a fuel feed pipe 12 inclinedly arranged on one side of the grate 11 and connected to the inner cavity of the grate 11, and a first flue gas outlet 2 opened on one side of the furnace body 1. The first flue gas outlet 2 is connected to the heat exchange chamber 3 and the first induced draft fan 4 through a pipeline. A flue gas inlet 15 is opened on one side of the furnace body 1. The output end of the second induced draft fan 9 is connected to the inner cavity of the furnace body 1 through the flue gas inlet 15. The furnace body 1 provides a suitable environment so that the fuel can burn efficiently. Through the fuel feed pipe 12, the fuel can be placed on the grate 11. Through the third induced draft fan 14 and the grate 11, the fuel on the grate 11 is heated and air can be introduced into the inner cavity of the furnace body 1 to promote fuel combustion.

[0021] Furthermore, the heat exchange chamber 3 is an air preheater. By using the heat exchange chamber 3, the air can be preheated using the heat from the waste flue gas, thereby improving the efficiency of fuel combustion.

[0022] The air preheater is internally provided with a heat exchange assembly, which comprises heat dissipation fins arranged in the inner cavity of the air preheater.

[0023] The above is only the preferred specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacements or changes according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A boiler with ultra-low nitrogen oxide emissions, comprising a boiler body, a heat exchange chamber (3), a first induced draft fan (4) and a chimney (6) connected in sequence, the output end of the first induced draft fan (4) and the chimney (6) being connected in communication through a connecting pipe (5) provided, characterized in that: The connecting pipe (5) is provided with an oxygen content detection device (7), and is also provided with an electric damper (8), and the other side of the electric damper (8) is provided with a second air blower (9) through a pipeline, and the output end of the second air blower (9) is communicated with the main furnace of the boiler through a pipeline.

2. A boiler with ultra-low nitrogen oxide emissions as claimed in claim 1, wherein: The signal output end of the oxygen content detection device (7) is provided with a control processor through a wire, and the signal output end of the control processor is connected with the electric damper (8) through a wire.

3. A boiler with ultra-low nitrogen oxide emissions as claimed in claim 1, wherein: The boiler body comprises a furnace body (1), a grate (11) arranged at the bottom of the furnace body (1), a third air blower (14) communicated with the grate (11), a fuel feeding pipe (12) arranged on one side of the grate (11) and communicated with the inner cavity of the grate (11), and a first flue gas outlet (2) arranged on one side of the furnace body (1), wherein the first flue gas outlet (2) is communicated with a heat exchange chamber (3) and a first air blower (4) through a pipeline, one side of the furnace body (1) is provided with a flue gas inlet (15), and the output end of the second air blower (9) is communicated with the inner cavity of the furnace body (1) through the flue gas inlet (15).

4. A boiler with ultra-low nitrogen oxide emissions as claimed in claim 1, wherein: The heat exchange chamber (3) is an air preheater for preheating air required for combustion.

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