CN214360254U

CN214360254U - Natural gas reformer

Info

Publication number: CN214360254U
Application number: CN202120269429.6U
Authority: CN
Inventors: 贺丙飞; 张欣禹; 李莉; 党士佳; 徐晓存; 金昌洙; 王玉玺; 索红亮
Original assignee: BEIJING IN-POWER NEW ENERGY CO LTD
Current assignee: BEIJING IN-POWER NEW ENERGY CO LTD
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-10-08
Anticipated expiration: 2031-01-29

Abstract

The utility model provides a natural gas reformer belongs to hydrogen manufacturing equipment technical field, include: the device comprises a reforming chamber, a combustion chamber, an intermediate chamber, a purification chamber, a flue gas pipeline and a heat exchange pipeline; the reforming chamber and the combustion chamber form a sleeve structure, and the combustion chamber is positioned in the center of the reforming chamber; the reforming chamber, the intermediate chamber and the purification chamber are communicated in sequence; the flue gas pipeline is communicated with the combustion chamber and penetrates through the middle chamber; the heat exchange pipeline is wound on the flue gas pipeline, and the tail end of the heat exchange pipeline is communicated with the reforming chamber. The utility model provides a pair of natural gas reformer, make full use of the heat that the combustion chamber produced, reduced the energy consumption of self, improved the thermal efficiency.

Description

Natural gas reformer

Technical Field

The utility model belongs to the technical field of hydrogen manufacturing equipment, more specifically say, relate to a natural gas reformer.

Background

At present, hydrogen energy is applied to the vigorous development in China, and the preparation of hydrogen is the key for ensuring the development of downstream technology. The method for preparing hydrogen mainly comprises the following steps: 1. hydrogen is produced by reforming fossil energy, and mainly comprises petroleum, natural gas, methanol and coal; 2. the water electrolysis hydrogen production mainly comprises alkaline water electrolysis hydrogen production, solid oxide water electrolysis hydrogen production and PEM water electrolysis hydrogen production; 3. hydrogen is produced by renewable energy sources. The hydrogen production by water electrolysis is high in cost, and the hydrogen production by renewable energy is limited by regions and can only be carried out in regions with rich wind power and photovoltaic resources. Compared with the prior art, the hydrogen production by reforming the fossil energy has more development prospect.

The steam reforming of natural gas is an important technology for hydrogen production, and has the main advantages that: 1. the raw materials are convenient and easy to obtain; 2. the conversion rate of natural gas is high; 3. hydrogen can be produced in a normal pressure reactor, and the requirement on the pressure resistance of equipment is low; 4. is easy to popularize.

However, there are also problems with current natural gas reforming: 1. because some application scenarios need to reduce the CO in the reformed gas to below 10ppm, such as PEM fuel cells, the existing removal method is mainly Pressure Swing Adsorption (PSA), which requires pressurization equipment, requires higher energy consumption, and affects the economy; 2. the reforming reaction needs a plurality of reactors connected in series, and the series pipeline increases pressure drop on one hand and increases heat loss on the other hand, so that the integration level is low; 3. the heat utilization is insufficient, and the heat management efficiency is low.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a natural gas reformer aims at solving the problem that current natural gas reformer has the energy consumption height, the thermal efficiency is low.

In order to achieve the above object, the utility model adopts the following technical scheme: there is provided a natural gas reformer comprising: the device comprises a reforming chamber, a combustion chamber, an intermediate chamber, a purification chamber, a flue gas pipeline and a heat exchange pipeline; the reforming chamber and the combustion chamber form a sleeve structure, and the combustion chamber is positioned in the center of the reforming chamber; the reforming chamber, the intermediate chamber and the purification chamber are communicated in sequence; the flue gas pipeline is communicated with the combustion chamber and penetrates through the middle chamber; the heat exchange pipeline is wound on the flue gas pipeline, and the tail end of the heat exchange pipeline is communicated with the reforming chamber.

As another embodiment of the present application, an igniter is installed at the top end of the combustion chamber, and the igniter includes an air pipeline, a combustible gas pipeline, a gas mixer, a ventilation pipeline, an ignition electrode and a burner; the gas mixer is positioned outside the combustion chamber, and the air pipeline and the combustible gas pipeline are respectively communicated with the gas mixer; the ventilation pipeline is used for communicating the gas mixer and the combustion chamber; the ignition electrode and the burner are both installed inside the ventilation pipeline, and the burner is close to the outlet end of the ventilation pipeline.

As another embodiment of the present application, the discharge end of the ignition electrode is hook-shaped.

As another embodiment of the application, a first air distributor is installed at one end, close to the flue gas pipeline, of the combustion chamber.

As another embodiment of the application, the top of the reforming chamber is provided with a premixing chamber, the premixing chamber is used for communicating the heat exchange pipeline with the reforming chamber, and the premixing chamber is provided with a natural gas inlet.

As another embodiment of the present application, a second air distributor is disposed between the premixing chamber and the reforming chamber.

As another embodiment of the present application, the reforming chamber has an annular cross section, and a plurality of first partitions are disposed inside the reforming chamber along a circumferential direction thereof, and divide the reforming chamber into a plurality of sector-shaped chambers.

As another embodiment of the present application, a second partition plate is disposed in the purification chamber, the second partition plate divides the purification chamber into a water gas shift chamber and a CO catalytic reaction chamber, and a through hole for communicating the water gas shift chamber with the CO catalytic reaction chamber is disposed on the second partition plate; the water-gas shift chamber is filled with shift reaction catalyst, and the CO catalytic reaction chamber is filled with CO reaction catalyst; the water-gas shift chamber is communicated with the middle chamber, and a hydrogen outlet is arranged on the CO catalytic reaction chamber.

As another embodiment of the application, a baffle plate is arranged in the water gas shift chamber and/or the CO catalytic reaction chamber.

As another embodiment of this application, be equipped with on the outer wall of purification cavity and press from both sides the cover, the flue gas pipeline with press from both sides the cover intercommunication, it discharges fume the pipe to be equipped with on the cover.

The utility model provides a pair of natural gas reformer's beneficial effect lies in: compared with the prior art, the utility model relates to a natural gas reformer, combustible gas and air take place oxidation reaction in the combustion chamber and emit a large amount of heats, and most heat transmits for the reformer chamber through convection current and heat-conducting mode, and another part heat enters into in the flue gas pipeline along with the flue gas. The heat exchange pipeline is wound on the flue gas pipeline, so that water in the heat exchange pipeline is gasified through heat exchange to form steam, the steam and natural gas are introduced into the reforming chamber, and a reforming reaction is carried out in the reforming chamber to obtain a mixed gas containing hydrogen and CO. The mixed gas enters the purifying chamber through the middle chamber and undergoes chemical reaction in the purifying chamber, so that CO in the mixed gas is eliminated. Because the flue gas pipeline runs through the middle chamber, the temperature of the mixed gas can be improved in a heat exchange mode, and the reaction rate of the mixed gas in the purification chamber is accelerated. The natural gas reformer makes full use of the heat generated by the combustion chamber, reduces the energy consumption of the natural gas reformer and improves the heat efficiency.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a natural gas reformer according to an embodiment of the present invention;

fig. 2 is a schematic cross-sectional structural diagram of a natural gas reformer according to an embodiment of the present invention;

fig. 3 is a schematic top view of a first air distributor according to an embodiment of the present invention;

fig. 4 is a schematic top view of a second air distributor according to an embodiment of the present invention.

In the figure: 1. a reforming chamber; 101. a heat-insulating layer; 102. a premix chamber; 103. a natural gas inlet; 104. a second air distributor; 105. a first separator; 106. air distribution holes; 2. a combustion chamber; 201. an igniter; 202. an air line; 203. a combustible gas pipeline; 204. a gas mixer; 205. a vent line; 206. an ignition electrode; 207. burning a nozzle; 209. a first air distributor; 210. a smoke vent; 3. an intermediate chamber; 4. a decontamination chamber; 401. a second separator; 402. a water gas shift chamber; 403. a CO catalytic reaction chamber; 404. a hydrogen outlet; 405. a baffle plate; 406. a jacket; 407. a smoke exhaust pipe; 5. a flue gas duct; 6. a heat exchange conduit.

Detailed Description

In order to make the technical problem, technical solution and advantageous effects to be solved by the present invention more clearly understood, the following description is given in conjunction with the accompanying drawings and embodiments to illustrate the present invention in further detail. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1 and 2 together, a description will now be given of a natural gas reformer according to the present invention. The natural gas reformer comprising: the device comprises a reforming chamber 1, a combustion chamber 2, an intermediate chamber 3, a purification chamber 4, a flue gas pipeline 5 and a heat exchange pipeline 6; the reforming chamber 1 and the combustion chamber 2 form a sleeve structure, and the combustion chamber 2 is positioned in the center of the reforming chamber 1; the reforming chamber 1, the intermediate chamber 3 and the purification chamber 4 are communicated in sequence; the flue gas pipeline 5 is communicated with the combustion chamber 2, and the flue gas pipeline 5 penetrates through the middle chamber 3; the heat exchange pipe 6 is wound around the flue gas pipe 5, and the end of the heat exchange pipe 6 is communicated with the reforming chamber 1.

The utility model provides a pair of natural gas reformer compares with prior art, and combustible gas and air take place oxidation reaction in the burning chamber and emit a large amount of heat, and reforming chamber 1 is transmitted through convection current and heat-conducting mode to most heat, and another part heat enters into in the flue gas pipeline 5 along with the flue gas. Because the heat exchange pipeline 6 is wound on the flue gas pipeline 5, water in the heat exchange pipeline 6 is gasified through heat exchange to form steam, the steam and natural gas are introduced into the reforming chamber 1, and a reforming reaction is carried out in the reforming chamber 1 to obtain a mixed gas containing hydrogen and CO. The mixed gas enters the purifying chamber 4 through the middle chamber 3, and chemical reaction occurs in the purifying chamber 4, so that CO in the mixed gas is eliminated. Because the flue gas pipeline 5 penetrates through the middle chamber 3, the temperature of the mixed gas can be increased in a heat exchange mode, and the reaction rate of the mixed gas in the purification chamber 4 is accelerated. The natural gas reformer fully utilizes the heat generated by the combustion chamber 2, reduces the energy consumption of the natural gas reformer and improves the heat efficiency.

In this embodiment, the reforming chamber 1 is a stainless steel cylinder, and the reforming chamber 1 is filled with a reforming catalyst. Absorbing external heat supply by natural gas and water vapor at the temperature of 700-:

CH4+H2O＝CO+3H2，△H＝+49.7kcal/mol；

CO+H2O＝CO2+H2，△H＝-10kcal/mol；

natural gas is converted to hydrogen by the above reaction.

An insulating layer 101 is installed outside the reforming chamber 1, and the insulating layer 101 may be made of fiber, such as acetate fiber, glass fiber, etc., or refractory material, such as corundum, etc. The thickness of the heat-insulating layer 101 is 20mm-40 mm.

The heat exchange pipeline 6 is made of metal, such as stainless steel, red copper and the like, and the red copper pipe is preferably selected due to the excellent heat conducting property of the red copper pipe. The heat exchange tubes 6 are located between the insulation 101 and the reformer chamber 1. The heat exchange pipeline 6 not only utilizes the waste heat of the combustion chamber 2 to change water into steam, but also plays a role in cooling the outer wall of the natural gas reformer, and effectively prevents the outer wall from overheating and overtemperature. The water in the heat exchange pipe 6 is deionized water.

As a specific embodiment of the natural gas reformer provided in the present invention, please refer to fig. 1, an igniter 201 is installed at the top end of the combustion chamber 2, the igniter 201 includes an air pipeline 202, a combustible gas pipeline 203, a gas mixer 204, a ventilation pipeline 205, an ignition electrode 206 and a burner 207; the gas mixer 204 is positioned outside the combustion chamber 2, and the air pipe 202 and the combustible gas pipe 203 are respectively communicated with the gas mixer 204; the ventilation pipe 205 is used for communicating the gas mixer 204 with the combustion chamber 2; the ignition electrode 206 and the burner 207 are both mounted inside the vent line 205, with the burner 207 near the outlet end of the vent line 205. In this embodiment, the igniter 201 is the source of heat for the entire natural gas reformer. The air line 202 is located at the top of the gas mixer 204 and the combustible gas line 203 is located at the side of the gas mixer 204. The air line 202 and the combustible gas line 203 respectively introduce air and combustible gas (e.g., natural gas) into the vent line 205, the flow relationship of the air and the natural gas being Q_{Air (a)}：Q_{Natural gas}Only in this range, 7-12, positive pressure ignition and stable combustion are possible. The gas mixer 204 is for mixing air and natural gas, and a baffle plate, a wire filler, a filler ring, or the like may be provided inside the gas mixer 204 to improve the mixing effect of the gas mixer 204. The ventilation pipeline 205 conveys the gas in the gas mixer 204 to the burner 207, the ignition electrode 206 is installed in cooperation with the burner 207, and the ignition electrode 206 provides instant energy for the ignition of the burner 207. The flame sprayed out from the burner 207 generates combustion reaction, the generated flue gas flows downwards, the reforming chamber 1 is heated to 700-800 ℃ to provide heat for the reforming reaction, and finally the flue gas carries waste heat to enterInto the flue gas duct 5.

As a specific embodiment of the present invention, referring to fig. 1, the discharge end of the ignition electrode 206 is bent. In this embodiment, the ignition electrode 206 penetrates the center of the burner 207, and the discharge end of the ignition electrode 206 is located below the burner 207. By setting the discharge end of the ignition electrode 206 to be hook-shaped, the discharge effect can be enhanced. The burner 207 is internally provided with a quincuncial head for guiding gas, the quincuncial head is made of ceramic, and the ceramic has the characteristic of high temperature resistance.

Referring to fig. 1 and 3, a first air distributor 209 is installed at one end of the combustion chamber 2 close to the flue gas pipe 5. In this embodiment, first air distributor 209 is located the bottom of combustion chamber 2, and first air distributor 209 is discoid, is equipped with exhaust hole 210 on the first air distributor 209, and exhaust hole 210 evenly arranges along the circumference of first air distributor 209, and the aperture d and the quantity n of exhaust hole 210 and the relation of flue gas volume S are: s is 0.25v pi d2, v is the airflow rate of the smoke vent 210, and the airflow rate v is between 5m/S and 15 m/S.

As a specific embodiment of the natural gas reformer provided in the present invention, please refer to fig. 1, the top of the reforming chamber 1 is provided with a pre-mixing chamber 102, the pre-mixing chamber 102 is used for communicating the heat exchange pipeline 6 and the reforming chamber 1, and the pre-mixing chamber 102 is provided with a natural gas inlet 103. The natural gas inlet 103 is located at the top of the premixing chamber 102, and pipes such as a control valve, a flow meter and a check valve are installed on a pipeline of the natural gas inlet 103 to ensure the supply of the natural gas required for the reforming reaction. The premixing chamber 102 is located at the top of the reformer chamber 1, and the premixing chamber 102 is filled with a metal filler for promoting sufficient mixing of natural gas and steam. The metal packing can be baffles, steel wire balls, metal rings and the like.

Referring to fig. 1 and 4, a second air distributor 104 is disposed between the premixing chamber 102 and the reforming chamber 1. In this embodiment, after being fully mixed in the premixing chamber 102, the natural gas and the steam enter the reforming chamber 1 through the second air distributor 104 for reaction. The second air distributor 104 is a passage through which the natural gas and the steam enter the reforming chamber 1 from the premixing chamber 102, and is circular, on which air distribution holes 106 are uniformly distributed, the air distribution holes 106 are circular, and have a diameter of 0.5D to 1.2D, and D is a particle diameter of the reforming catalyst. The air distribution holes 106 are arranged in a plurality of concentric circles.

As a specific embodiment of the natural gas reformer according to the present invention, please refer to fig. 1 and 2, a cross section of the reforming chamber 1 is annular, a plurality of first partitions 105 are disposed inside the reforming chamber 1 along a circumferential direction of the reforming chamber, and the first partitions 105 divide the reforming chamber 1 into a plurality of fan-shaped chambers. In this embodiment, the number of the sector-shaped chambers is adjusted according to the size of the natural gas reformer, and is generally 5 to 10. The first partition 105 is made of metal and has a rectangular shape, thereby performing heat transfer and heat conduction. The first partition 105 is connected to the outer wall of the combustion chamber 2 and the outer wall of the reforming chamber 1, respectively, for transferring heat of the combustion chamber 2 to the reforming chamber 1.

As a specific embodiment of the natural gas reformer provided in the present invention, please refer to fig. 1, a second partition 401 is disposed in the purification chamber 4, the second partition 401 divides the purification chamber 4 into a water gas shift chamber 402 and a CO catalytic reaction chamber 403, and a through hole for communicating the water gas shift chamber 402 and the CO catalytic reaction chamber 403 is disposed on the second partition 401; the water gas shift chamber 402 is filled with shift reaction catalyst, and the CO catalytic reaction chamber 403 is filled with CO reaction catalyst; the water gas shift chamber 402 is communicated with the middle chamber 3, and a hydrogen outlet 404 is arranged on the CO catalytic reaction chamber 403. In the present embodiment, the reforming reaction is performed to obtain hydrogen gas, but the mixed gas after the reforming reaction contains CO, and the CO mixed in the hydrogen gas poisons the hydrogen fuel cell catalyst, so that it is necessary to remove CO from the hydrogen gas, and the purge chamber 4 is a place where CO in the mixed gas is removed. The water gas shift chamber 402 is filled with shift reaction catalyst, and the generated CO and H2O react to produce CO2 and H2, wherein the shift reaction temperature is 200 ℃ and 250 ℃, and the pressure is 0-1.0 MPa. The catalyst filled in the CO catalytic reaction chamber 403 may be a CO selective oxidation catalyst or a CO methanation catalyst, and the difference between the two catalysts is that the generated chemical reactions are different, and when the CO selective oxidation catalyst is filled, an air inlet needs to be arranged in the reaction chamber. The temperature of the CO catalytic reaction is 130-200 ℃, and the pressure is 0-1.0 Mpa.

The mixed gas contains about 10 percent of CO, the content of the CO can be reduced to below 1 percent after the water-gas shift reaction, and then the CO is further removed to below 10ppm through a CO catalytic reaction.

Water-gas shift reaction: CO + H2O ═ CO2+ H2,. DELTA.h ═ 10 kcal/mol;

selective oxidation of CO: CO +1/2O2 ═ CO2 Δ H ═ -67.6 kcal/mol;

selective methanation of CO: CO +3H2 ═ CH4+ H2O Δ H ═ -206.2 kJ/mol.

Referring to fig. 1, a baffle 405 is disposed in the water gas shift chamber 402 and/or the CO catalytic reaction chamber 403. In this embodiment, the baffle plate 405 is disposed in the water gas shift chamber 402 and/or the CO catalytic reaction chamber 403, and the gas flow is zigzag flowing through the baffle plate 405, so that the contact time of the reaction gas and the catalyst is prolonged, the reaction efficiency is improved, and the CO removal effect is ensured.

As a specific embodiment of the natural gas reformer provided in the present invention, please refer to fig. 1, the outer wall of the purification chamber 4 is provided with a jacket 406, the flue gas pipe 5 is communicated with the jacket 406, and the jacket 406 is provided with a smoke exhaust pipe 407. In this embodiment, the jacket 406 is an annular tube that surrounds the purge chamber 4. The number of flue gas ducts 5 is two, and the outlets of the two flue gas ducts 5 are located at the side wall and the top of the jacket 406, respectively. The flue gas enters the jacket 406 from the side wall and the top of the jacket 406, respectively, so that the flue gas can circulate in the jacket 406, thereby heating the gas in the purification chamber 4 to the temperature required for the reaction.

The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.

Claims

1. A natural gas reformer, characterized by comprising: the device comprises a reforming chamber, a combustion chamber, an intermediate chamber, a purification chamber, a flue gas pipeline and a heat exchange pipeline; the reforming chamber and the combustion chamber form a sleeve structure, and the combustion chamber is positioned in the center of the reforming chamber; the reforming chamber, the intermediate chamber and the purification chamber are communicated in sequence; the flue gas pipeline is communicated with the combustion chamber and penetrates through the middle chamber; the heat exchange pipeline is wound on the flue gas pipeline, and the tail end of the heat exchange pipeline is communicated with the reforming chamber.

2. A natural gas reformer in accordance with claim 1, wherein an igniter is installed at a top end of the combustion chamber, the igniter including an air line, a combustible gas line, a gas mixer, a ventilation line, an ignition electrode, and a burner; the gas mixer is positioned outside the combustion chamber, and the air pipeline and the combustible gas pipeline are respectively communicated with the gas mixer; the ventilation pipeline is used for communicating the gas mixer and the combustion chamber; the ignition electrode and the burner are both installed inside the ventilation pipeline, and the burner is close to the outlet end of the ventilation pipeline.

3. A natural gas reformer in accordance with claim 2, wherein the discharge end of said ignition electrode is hook-shaped.

4. A natural gas reformer in accordance with claim 1, wherein a first air distributor is installed at an end of said combustion chamber adjacent to said flue gas duct.

5. A natural gas reformer according to claim 1, wherein a premixing chamber is provided at the top of the reforming chamber, the premixing chamber is used for communicating the heat exchange pipe and the reforming chamber, and a natural gas inlet is provided on the premixing chamber.

6. A natural gas reformer according to claim 5, wherein a second air distributor is provided between the premixing chamber and the reforming chamber.

7. A natural gas reformer in accordance with claim 1, wherein said reforming chamber has a ring-shaped cross section, and a plurality of first partitions are provided in the interior of said reforming chamber along the circumferential direction thereof, said first partitions dividing said reforming chamber into a plurality of sector-shaped chambers.

8. A natural gas reformer according to claim 1, wherein a second partition is provided in the purge chamber, the second partition dividing the purge chamber into a water gas shift chamber and a CO catalytic reaction chamber, the second partition being provided with a through hole for communicating the water gas shift chamber and the CO catalytic reaction chamber; the water-gas shift chamber is filled with shift reaction catalyst, and the CO catalytic reaction chamber is filled with CO reaction catalyst; the water-gas shift chamber is communicated with the middle chamber, and a hydrogen outlet is arranged on the CO catalytic reaction chamber.

9. A natural gas reformer according to claim 8, wherein baffle plates are provided in the water gas shift chamber and/or the CO catalytic reaction chamber.

10. The natural gas reformer according to claim 1, wherein a jacket is provided on an outer wall of the purification chamber, the flue gas duct is communicated with the jacket, and a smoke discharge pipe is provided on the jacket.