A NO 2 Gas heating reaction to generate NO gas reformer

Abstract

The present invention provides a NO2 gas heating reaction to generate NO gas conversion furnace, the furnace core is arranged in the furnace body through the opening, a gas heating chamber is formed between the furnace core shell and the furnace body, a graphite layer is arranged on the outer wall of the gas guide pipe, the outer wall of the gas guide pipe is distributed with through holes, the first end of the gas guide pipe is located in the gas heating chamber, the second end is connected to the graphite layer and the gas outlet, the first sealing ring isolates the gas outlet from the gas heating chamber, the second sealing ring isolates the gas outlet from the outside, the air inlet pipe is connected to the gas heating chamber, the air outlet pipe is connected to the air outlet, and the heating device is arranged on the outer wall of the furnace body. The furnace core of the gas conversion furnace has a graphite layer, which can further convert NO2 into NO, and can also avoid the influence of the relatively low temperature of the newly added gas, and avoid that part of the NO in the gas to be discharged from the gas outlet pipe will be converted back into NO2, and has a high NO conversion efficiency. In addition, the furnace body and the furnace core are independent components before being combined, and the furnace core can be replaced after the furnace core reaches a certain consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of gas detection equipment, and in particular to a NO2 gas heating reaction to generate NO gas conversion furnace. Background Art

[0002] As motor vehicle inspection agencies need to update motor vehicle emission detection instruments that meet the latest national standards, current cars need to measure NOx emissions. NOx mainly includes NO and NO2. Since NO2 has unstable chemical properties and a boiling point of 21.1 degrees, it is difficult to measure directly. For this reason, the standard stipulates that NO2 can be measured by converting it into NO. The standard requires that the conversion efficiency of the conversion device must exceed 90% and the response time of the instrument must meet the requirements. Most of the products on the market are currently on the edge of this qualification. Some are not efficient, and some have low flow rate response speeds that do not meet the requirements. Necessarily, it is necessary to design a converter device that can improve the NO conversion efficiency and gas pass rate. Summary of the invention

[0003] The purpose of the present invention is to provide a NO gas conversion furnace for heating NO2 gas to generate NO gas in order to solve the above-mentioned problems, which can improve the NO conversion efficiency and the NO pass rate after conversion.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A NO2 gas heating reaction to generate NO gas conversion furnace, comprising a furnace body, a furnace core, an air inlet pipe, an air outlet pipe and a heating device, the furnace body having an opening on one side, the furnace core being arranged in the furnace body through the opening, the furnace core comprising a furnace core shell, a graphite layer, an air guide pipe and an air outlet hole, a gas heating chamber being formed between the furnace core shell and the furnace body, the air guide pipe and the graphite layer being arranged in the furnace core shell, the graphite layer being arranged on the outer wall of the air guide pipe, through holes being distributed on the outer wall of the air guide pipe, a first end of the air guide pipe being located in the gas heating chamber, a second end of the air guide pipe being connected to the air outlet hole with the graphite layer, a first sealing ring and a second sealing ring being arranged on the outer wall of the furnace core shell, the first sealing ring and the second sealing ring being respectively located on both sides of the air outlet hole, the first sealing ring being used to isolate the air outlet hole from the gas heating chamber, the second sealing ring being used to isolate the air outlet hole from the outside, the air inlet pipe being connected to the gas heating chamber, the air outlet pipe being connected to the air outlet hole, and the heating device being arranged on the outer wall of the furnace body.

[0006] Furthermore, the furnace body structure is a cylindrical container, the furnace core structure is a cylindrical rod, and the air inlet pipe is arranged on the far side of the first end of the air guide pipe.

[0007] Furthermore, a catalytic reactant is disposed in the graphite layer.

[0008] Furthermore, the catalytic reactant is metallic molybdenum.

[0009] Furthermore, the through holes distributed on the outer wall of the air guide tube are threaded holes.

[0010] Furthermore, there are multiple air guide tubes.

[0011] Furthermore, the furnace core has a handle extending out of the furnace body.

[0012] The beneficial effects of the present invention are:

[0013] By adopting the above technical solution, the furnace core of the NO2 gas conversion furnace of the present invention for generating NO gas by heating reaction has a graphite layer, which can further convert NO2 into NO, and can also avoid the influence of the relatively low temperature of the newly added gas, and avoid that part of the NO in the gas to be discharged from the gas outlet pipe will be converted back into NO2, and has a high NO conversion efficiency. In addition, the furnace body and the furnace core are independent components before being combined, and the furnace core can be replaced after the furnace core reaches a certain consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0015] Figure 1 It is a schematic diagram of the overall structure of the gas reformer of the present invention;

[0016] Figure 2 It is a schematic diagram of the planed surface structure of the gas conversion furnace of the present invention.

[0017] Figure numerals: 1. furnace body; 11. opening; 12. gas heating chamber; 2. furnace core; 21. furnace core shell; 22. graphite layer; 23. air guide pipe; 24. air outlet; 25. first sealing ring; 26. second sealing ring; 27. handle; 3. air inlet pipe; 4. air outlet pipe; 5. heating device. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0019] like Figure 1-2As shown, a NO2 gas heating reaction to generate NO gas conversion furnace includes a furnace body 1, a furnace core 2, an air inlet pipe 3, an air outlet pipe 4 and a heating device 5. One side of the furnace body 1 has an opening 11, and the furnace core 2 is arranged in the furnace body 1 through the opening 11. The furnace core 2 includes a furnace core shell 21, a graphite layer 22, an air guide pipe 23 and an air outlet 24. A gas heating chamber 12 is formed between the furnace core shell 21 and the furnace body 1. The air guide pipe 23 and the graphite layer 22 are arranged in the furnace core shell 21. The graphite layer 22 is arranged on the outer wall of the air guide pipe 23. The outer wall of the air guide pipe 23 is distributed with through holes. The first end of the air guide pipe 23 is located in the gas heating chamber 12, and the second end of the air guide pipe 23 is connected to the graphite layer 22 to form an air outlet 24. The outer wall of the furnace core shell 21 is provided with a first sealing ring 25 and a second sealing ring 26. The first sealing ring 25 and the second sealing ring 26 are respectively located on both sides of the air outlet 24. The first sealing ring 25 is used to isolate the air outlet 24 from the gas heating chamber 12, and the second sealing ring 26 is used to isolate the air outlet 24 from the outside world. The air inlet pipe 3 is connected to the gas heating chamber 21, the air outlet pipe 4 is connected to the air outlet 24, and the heating device 5 is arranged on the outer wall of the furnace body 1.

[0020] The furnace body 1 and the furnace core 2 are independent components before being combined. The furnace core 2 is inserted into the furnace body 1 for combination. The first sealing ring 25 and the second sealing ring 26 at both ends of the gas outlet 24 of the furnace core 2 divide the interior of the furnace body 1 into two closed spaces that are not directly connected, namely the gas heating chamber 12 and the exhaust space between the gas outlet 24 and the gas outlet pipe 4.

[0021] Before inputting the gas to be detected, the heating device 5 is turned on for preheating, so that the gas heating chamber 12 and the furnace core shell 21 reach a certain temperature and maintain the temperature, which is generally 250°C-320°C. After preheating, the gas to be detected enters the furnace body 1 through the air inlet pipe 3, passes through the gas heating chamber 12 and enters the air guide pipe 23 from the first end of the air guide pipe 23, and can enter the graphite layer 22 through the through hole on the air guide pipe 23, wherein the through hole can be set as a threaded hole to accelerate the gas to be detected to pass through the through hole and diffuse rapidly in the graphite layer 22, and the cross-section of the air guide pipe 23 can be set as small as possible, and multiple air guide pipes 23 can be set to take into account the diffusion speed and ensure the smooth flow of gas, and finally discharged from the air outlet pipe 4 as gas that meets the detection conditions.

[0022] Part of the NO2 in the gas to be detected is converted into NO and O2 in the high temperature environment in the gas heating chamber 12 and the air duct 23, and part of the NO2 reacts with graphite in the graphite layer 22 to generate NO and CO2 in the high temperature environment. Since graphite has poor thermal conductivity at high temperatures, it can ensure that the temperature of the gas to be detected is balanced while being in full contact with the graphite. It also has a heat-insulating effect, and the relatively low temperature of the newly added gas from the intake pipe 3 cannot affect the outer wall of the air duct 23. Since the conversion between NO2 and NO is a reversible reaction, the reaction is carried out in both directions. The higher the temperature, the higher the conversion rate of NO2 to NO. If the temperature in the air duct 23 is affected by the relatively low temperature of the newly added gas, part of the NO in the gas to be discharged from the outlet pipe 4 will be converted back into NO2, which will affect the conversion effect of the converter. The setting of the graphite layer 22 effectively avoids this problem.

[0023] Since NO2 cannot fully react with graphite in the graphite layer 22, in order to achieve a higher NO generation rate, a catalytic reactant is provided in the graphite layer 22. Here, metal molybdenum Mo is used as the catalytic reactant, and Mo can promote the reaction between NO2 and graphite.

[0024] Furthermore, since the furnace body 1 and the furnace core 2 are independent components before being combined, the furnace core 2 can be replaced after the furnace core 2 reaches a certain consumption, and a handle 27 is provided on one side of the furnace core 2 to facilitate the installation operation of the furnace core 2.

[0025] Specifically, the furnace body 1 is a cylindrical container, the furnace core 2 is a cylindrical rod, and the air inlet pipe 3 is arranged at the far side of the first end of the air guide pipe 23. The gas enters the gas heating chamber 12 from the air inlet pipe 3, reaches the first end of the air guide pipe 23 along the gas heating chamber 12 from the far side of the first end of the air guide pipe 23, and then enters the air guide pipe 23 to flow in the furnace core shell 21 and be discharged along the air outlet 24. The gas flows smoothly and is fully heated along the entire path, and NO2 in the gas can be fully converted into NO.

[0026] The above embodiments of the present invention are not intended to limit the protection scope of the present invention, and the implementation modes of the present invention are not limited thereto. All other modifications, replacements or changes made to the above structures of the present invention based on the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, should fall within the protection scope of the present invention.

Claims

1. A NO2 gas heating reaction to generate NO gas converter, characterized in that: The invention comprises a furnace body, a furnace core, an air inlet pipe, an air outlet pipe and a heating device. One side of the furnace body has an opening, and the furnace core is arranged in the furnace body through the opening. The furnace core comprises a furnace core shell, a graphite layer, an air guide pipe and an air outlet hole. A gas heating chamber is formed between the furnace core shell and the furnace body. The air guide pipe and the graphite layer are arranged in the furnace core shell. The graphite layer is arranged on the outer wall of the air guide pipe. Through holes are distributed on the outer wall of the air guide pipe. The first end of the air guide pipe is located in the gas heating chamber, and the second end of the air guide pipe is connected to the graphite layer and the air outlet hole. The outer wall of the furnace core shell is provided with a first sealing ring and a second sealing ring, and the first sealing ring and the second sealing ring are respectively located on both sides of the air outlet, the first sealing ring is used to isolate the air outlet from the gas heating chamber, and the second sealing ring is used to isolate the air outlet from the outside world, the air inlet pipe is connected to the gas heating chamber, and the air outlet pipe is connected to the air outlet, the heating device is arranged on the outer wall of the furnace body, the air inlet pipe is arranged on the far side of the first end of the air guide pipe, the through holes distributed on the outer wall of the air guide pipe are threaded holes, and the air guide pipe has multiple threads.

2. A NO2 gas heating reaction to generate NO gas converter according to claim 1, characterized in that: The furnace body structure is a cylindrical container, and the furnace core structure is a cylindrical rod.

3. A NO2 gas heating reaction to generate NO gas converter according to claim 1, characterized in that: Catalytic reactants are arranged in the graphite layer.

4. A NO2 gas heating reaction to generate NO gas converter according to claim 3, characterized in that: The catalytic reactant is metallic molybdenum.

5. The NO2 gas heating reaction to generate NO gas converter according to claim 1, characterized in that: The furnace core is provided with a handle extending out of the furnace body.

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