Continuous catalytic reforming device and method

Abstract

The invention relates to a continuous catalytic reforming device and method.The continuous catalytic reforming device comprises a plurality of reactors, each reactor comprises a reactor body and at least two reaction chambers which are arranged in the reactor body and vertically arranged at intervals, and each reaction chamber is internally provided with at least one catalyst module; a flow guide device is arranged below each reaction chamber; the outlet end of the feed gas inlet pipe is connected with the gas inlet at the bottom of each reactor main body in an on-off manner; the first heat exchange type gas heating device is connected to the raw material gas inlet pipe in series and is used for heat exchange between the converter gas and the raw material gas so as to heat the raw material gas to a preset target temperature; the inlet end of the reducing gas outlet pipe is connected with the gas outlet in the top of each reactor main body in an on-off manner. The problems that continuous production cannot be achieved in the prior art, the high-temperature tube nest of a traditional high-temperature tube nest structure is prone to damage, and cost and maintenance cost are high are solved.

Description

Technical Field

[0001] The present invention relates to the field of catalytic reforming, and particularly to a continuous catalytic reforming device and method. Background Art

[0002] Hydrogen energy is the cleanest energy source with the greatest development potential in the 21st century. Replacing "carbon" with "hydrogen" has become an important direction in the steel industry. The hydrogen-based shaft furnace direct reduction iron-hydrogen metallurgy technology is considered an important technology in the steel industry. At present, the main methods for preparing reducing gas used in hydrogen-based shaft furnaces mainly include:

[0003] (1) Natural gas reforming process (dry / wet reforming): Due to the scarcity of natural gas resources, the operating cost of this process is high, and it cannot be produced on a large scale currently; (2) Coke oven gas - COG process (dry / wet reforming): Coke oven gas resources are relatively rich, and it is considered the most suitable path for preparing reducing gas for hydrogen metallurgy in the steel industry.

[0004] In the metallurgical industry, the device that provides catalytic reforming reducing gas for gas-based shaft furnaces is mainly the catalytic reforming furnace. The catalytic reforming furnace is the core equipment in the process of preparing reducing gas, including plate type and shell-and-tube type. Currently, the mainly commercially operated one is the shell-and-tube heated reforming furnace, which can heat the hydrogen-containing gas source to 800 - 1000 °C and undergo reforming reaction to provide reducing gas for the hydrogen-based shaft furnace. However, the following problems are likely to occur during the manufacturing and use of this device:

[0005] (1) The material requirements for the high-temperature shell-and-tube in the core components are harsh, resulting in high costs, and the high requirements for weld quality lead to great processing difficulties;

[0006] (2) Carbon deposition reactions occur during the use of hydrogen-containing gases (CH4 ←→ C + 2H2, 2CO ←→ C + CO2, CO + H2 ←→ C + H2O), and the product carbon black adheres to the inner wall of the shell-and-tubes, affecting heat transfer, causing local overheating of the first-stage furnace tubes (shell-and-tubes) and shortening the service life;

[0007] (3) The flange of the hard connection component at the joint between the furnace tube and the flue gas pipeline is prone to deformation under high temperature, resulting in reduced pipeline sealing performance, leakage of the converted product gas, and even the generation of open flames, so that the equipment has to stop running, affecting stable production.

[0008] (4) The device has many structural components, and the maintenance is cumbersome. The device cannot run during maintenance, reducing production efficiency.

[0009] (5) Once the device fails, it can only be shut down for maintenance, and continuous production cannot be achieved in the case of equipment failure. Summary of the Invention

[0010] The object of the present invention is to provide a continuous catalytic reforming device and method, which solves the problems that continuous production cannot be achieved in the prior art, the high-temperature tubular structure of the traditional high-temperature tubular is easily damaged, and the cost and maintenance cost are high.

[0011] The object of the present invention can be achieved by the following technical solutions:

[0012] The present invention provides a continuous catalytic reforming device, including: a plurality of reactors, each reactor includes a reactor main body and at least two reaction chambers arranged at intervals up and down in the reactor main body, at least one group of catalyst modules is arranged in each reaction chamber, and a diversion device is arranged below each reaction chamber; a raw gas inlet pipe, the outlet end of which is connected to the air inlet at the bottom of each reactor main body in a switchable manner; a first heat exchange type gas heating device, which is connected in series on the raw gas inlet pipe for heat exchange between converter gas and raw gas to heat the temperature of the raw gas to a preset target temperature; a reducing gas outlet pipe, the inlet end of which is connected to the air outlet at the top of each reactor main body in a switchable manner.

[0013] In a preferred embodiment of the present invention, at least one support cylinder with an open top and a plurality of air holes at the bottom is arranged in each reaction chamber, and each group of catalyst modules is filled in the corresponding support cylinder; each group of catalyst modules includes one layer or at least two layers of catalyst brick layers stacked up and down, and each layer of catalyst brick layer includes a plurality of porous catalyst bricks spliced with each other. The porous catalyst brick is a block structure with a plurality of through holes made by sintering the catalyst.

[0014] In a preferred embodiment of the present invention, the composition of the porous catalyst brick includes Al2O3, Ni, MgO, CaO and BaO, and the content of MgO ≥ 70%.

[0015] In a preferred embodiment of the present invention, the porous catalyst brick is a regular hexagonal block.

[0016] In a preferred embodiment of the present invention, an installation opening is provided on the side wall of the reactor main body corresponding to each reaction chamber, and a baffle is detachably and hermetically installed at the installation opening.

[0017] In a preferred embodiment of the present invention, a first water cooling channel is arranged in the side wall of the reactor main body, and a first interface and a second interface communicating with the first water cooling channel are arranged on the outer side wall of the reactor main body near the installation opening; a second water cooling channel is arranged in the baffle, and a baffle water inlet and a baffle water outlet communicating with both ends of the first water cooling channel are arranged on the outer side wall of the baffle. The baffle water inlet and the baffle water outlet can be connected to the first interface and the second interface respectively through a water inlet pipe and a water outlet pipe, and a water inlet valve and a water outlet valve are arranged on the water inlet pipe and the water outlet pipe respectively.

[0018] In a preferred embodiment of the present invention, the flow guiding device includes a rectifying grille and a flow guiding plate assembly arranged at intervals up and down. The flow guiding plate assembly includes a plurality of vertical plates arranged in parallel at intervals.

[0019] In a preferred embodiment of the present invention, gas analysis components are provided above the reaction chamber at the top, below the reaction chamber at the bottom, and between two adjacent reaction chambers, for analyzing the temperature and components of the gas.

[0020] In a preferred embodiment of the present invention, the first heat exchange type gas heating device includes a housing arranged horizontally axially. Inside the housing, a plurality of heat exchange tubes arranged horizontally axially are provided. The two ends of the heat exchange tubes are respectively communicated with the two end faces of the housing and are communicated with the raw material gas inlet pipe. A converter gas inlet and a converter gas outlet are provided on the side wall of the housing.

[0021] In a preferred embodiment of the present invention, a plurality of first partition plates and a plurality of second partition plates are also arranged at intervals and staggered along the axial direction inside the housing. A gap is left between the lower end of the first partition plate and the bottom side wall of the housing, and a gap is left between the upper end of the second partition plate and the top side wall of the housing.

[0022] In a preferred embodiment of the present invention, a second heat exchange type gas heating device is also connected in series on the reducing gas outlet pipe. The structure of the second heat exchange type gas heating device is the same as that of the first heat exchange type gas heating device. The two ends of the heat exchange tubes of the second heat exchange type gas heating device are communicated with the reducing gas outlet pipe.

[0023] The present invention also provides a continuous catalytic reforming method, using the above-mentioned continuous catalytic reforming device. The continuous catalytic reforming method includes: introducing the raw material gas into the raw material gas inlet pipe, and performing heat exchange with the converter gas in the first heat exchange type gas heating device to heat the temperature of the raw material gas to a preset target temperature; introducing the heat-exchanged raw material gas into at least one reactor, and reacting with the catalyst module in each reaction chamber of the reactor to obtain reducing gas; discharging the reducing gas through the reducing gas outlet pipe.

[0024] As described above, the continuous catalytic reforming apparatus and method of the present invention can control multiple reactors to provide reforming reducing gas for the gas-based shaft furnace, ensuring that when one or more reactors stop operating, other reactors can still provide continuous reducing gas for the gas-based shaft furnace, guaranteeing the continuous and stable operation of production. The first heat exchange type gas heating device is provided, and multiple reactors share one gas heating device, saving the construction cost of the device; the temperature of the converter gas is relatively high, and the heat of the converter gas is used to exchange heat with the raw material gas, which can quickly heat the raw material gas to the target temperature with lower energy consumption. At least two reaction chambers are provided in each reactor from bottom to top, and a diversion device is provided below each reaction chamber, which can play a role in guiding the airflow, making the airflow distribution entering the catalyst more uniform and more conducive to making full use of all the catalysts. At least one layer of catalyst module is provided in each reaction chamber, and the catalyst modules in the reaction chamber can be exchanged. When the catalyst is "poisoned" and inactivated, the catalyst can be replaced, which is more flexible. This device does not use the shell-and-tube structure of the traditional catalytic reforming furnace, and there is no need to install high-temperature tubes, reducing the cost and maintenance cost of the high-temperature tubes; it avoids the product carbon black in the original catalytic reforming process from adhering to the high-temperature tubes, causing uneven heating of the high-temperature tubes and damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The following drawings are only intended to illustrate and explain the present invention schematically and do not limit the scope of the present invention.

[0026] Among them:

[0027] Figure 1 is a schematic structural diagram of the continuous catalytic reforming apparatus provided by the present invention.

[0028] Figure 2 is a partial enlarged view of one of the reaction chambers provided by the present invention.

[0029] Figure 3 is Figure 1 a cross-sectional view at the porous support plate of the reactor in

[0030] Figure 4 is a schematic diagram of the filling of porous catalyst bricks.

[0031] Figure 5 is a schematic diagram of the porous catalyst brick.

[0032] Figure 6 is a partial enlarged view at the baffle provided by the present invention.

[0033] Figure 7 is a cross-sectional view at the second partition plate of the first heat exchange type gas heating device provided by the present invention.

[0034] Explanation of the reference numerals in the drawings:

[0035] 1. Reactor; 11. Reactor main body; 111. Installation port; 112. First interface; 113. Second interface; 12. Catalyst module; 121. Porous catalyst brick; 122. Through hole; 13. Support cylinder; 131. Annular sealing plate; 132. Porous support plate; 14. Baffle; 141. Baffle water inlet; 142. Baffle water outlet; 143. Water inlet valve; 144. Water outlet valve; 15. Flow guiding device; 151. Rectifying grid; 152. Vertical plate; 16. Gas analysis component;

[0036] 2. Raw gas inlet pipe; 21. Inlet branch pipe; 22. First switching valve; 23. Deflector;

[0037] 3. First heat exchange type gas heating device; 31. Housing; 32. Heat exchange tube; 33. Converter gas inlet; 34. Converter gas outlet; 35. First partition; 36. Second partition;

[0038] 4. Reducing gas outlet pipe; 41. Outlet branch pipe; 42. Second switching valve;

[0039] 5. Second heat exchange type gas heating device. Detailed implementation manners

[0040] For a clearer understanding of the technical features, objectives, and effects of the present invention, the specific implementation manners of the present invention will now be described with reference to the accompanying drawings.

[0041] As Figures 1 to 7 shown, the present application provides a continuous catalytic reforming device, including:

[0042] A plurality of reactors 1, each reactor 1 includes a reactor main body 11 and at least two reaction chambers arranged at intervals up and down in the reactor main body 11. At least one set of catalyst modules 12 is provided in each reaction chamber, and a flow guiding device 15 is provided below each reaction chamber;

[0043] A raw gas inlet pipe 2, the outlet end of which is connectable to and disconnectable from the inlet of the bottom of each reactor main body 11;

[0044] A first heat exchange type gas heating device 3, connected in series to the raw gas inlet pipe 2, for heat exchange between converter gas and raw gas to heat the temperature of the raw gas to a preset target temperature;

[0045] A reducing gas outlet pipe 4, the inlet end of which is connectable to and disconnectable from the outlet of the top of each reactor main body 11.

[0046] This device is mainly used for catalytic reforming of hydrogen-rich gas to prepare reducing gas, providing catalytic reforming reducing gas for the shaft furnace with gas-based, and meeting the demand for a large amount of continuous reducing gas required for the production of the shaft furnace with gas-based. The raw material gas can be, for example, hydrogen-rich gas such as converter gas and coke oven gas. After the raw material gas enters the raw material gas inlet pipe 2, under the action of the first heat exchange type gas heating device 3, the raw material gas exchanges heat with the converter gas to heat the temperature of the raw material gas to the preset target temperature. After heating, the raw material gas is respectively introduced into each reactor main body 11 communicated with the raw material gas inlet pipe 2. The raw material gas passes through each reaction chamber from bottom to top in turn, and catalytic reaction occurs in each reaction chamber. The obtained reducing gas is discharged through the reducing gas outlet pipe 4 and can be used for the next step of the shaft furnace with gas-based.

[0047] Thus, the continuous catalytic reforming device of the present application can control multiple reactors 1 to provide reforming reducing gas for the shaft furnace with gas-based, ensuring that when a single or multiple reactors 1 stop running, other reactors 1 can still provide continuous reducing gas for the shaft furnace with gas-based, ensuring the continuous and stable operation of production. The first heat exchange type gas heating device 3 is provided, and multiple reactors 1 share a gas heating device, saving the construction cost of the device; the temperature of the converter gas is relatively high (about 1400 - 1500 °C), and the heat of the converter gas is used to exchange heat with the raw material gas, which can quickly heat the raw material gas to the target temperature and has lower energy consumption. At least two reaction chambers are provided in each reactor 1 from bottom to top, and a diversion device 15 is provided below each reaction chamber, which can play a role in diverting the air flow, making the air flow entering the catalyst more evenly distributed, and being more conducive to making full use of all the catalysts. At least one layer of catalyst module 12 is provided in each reaction chamber, and the catalyst module 12 in the reaction chamber can be replaced. When the catalyst is "poisoned" and inactivated, the catalyst can be replaced, which is more flexible. This device does not use the shell-and-tube structure of the traditional catalytic reforming furnace, and there is no need to install high-temperature tubes, reducing the cost and maintenance cost of the high-temperature tubes; it avoids the product carbon black adhering to the high-temperature tubes during the original catalytic reforming process, resulting in uneven heating of the high-temperature tubes and damage.

[0048] In a specific implementation manner, in order to facilitate the on-off of the raw material gas inlet pipe 2 and the reducing gas outlet pipe 4 with each reactor main body 11, the air inlet of each reactor main body 11 is connected to the raw material gas inlet pipe 2 through an air inlet branch pipe 21, and a first on-off valve 22 is provided on the air inlet branch pipe 21; the air outlet of each reactor main body 11 is connected to the reducing gas outlet pipe 4 through an air outlet branch pipe 41, and a second on-off valve 42 is provided on the air outlet branch pipe 41.

[0049] The axes of the general raw gas inlet pipe 2, the first heat exchange type gas heating device 3, and the reducing gas outlet pipe 4 are all horizontally arranged, the axis of the reactor main body 11 is vertically arranged, and the axes of each intake branch pipe 21 and each outlet branch pipe 41 are all vertically arranged. The intake ports and outlet ports of multiple reactors 1 are respectively connected to the corresponding intake branch pipes 21 and outlet branch pipes 41, and the diameters of the intake ports and outlet ports of the reactor 1 are the same as those of the intake branch pipes 21 and outlet branch pipes 41 respectively.

[0050] Furthermore, at least one support cylinder 13 with an open top and multiple ventilation holes at the bottom is provided in each reaction chamber, and each group of catalyst modules 12 is filled in the corresponding support cylinder 13.

[0051] Refer to Figure 2 and Figure 3 , specifically, the support cylinder 13 is formed by enclosing an annular sealing plate 131 and a porous support plate 132 connected to the bottom of the annular sealing plate 131. The porous support plate 132 has multiple ventilation holes. The cross-sectional shape of the support cylinder 13 matches the cross-sectional shape of the reactor main body 11. Each group of catalyst modules 12 fills the entire cross-sectional area inside the support cylinder 13, and the number of layers of the catalyst brick layer is also determined according to the required catalyst height. The annular sealing plate 131 should be made of a heat-resistant sealing plate, and the porous support plate 132 is made of a cast heat-resistant steel plate to adapt to the high-temperature environment inside the reactor main body 11. Each group of catalyst modules 12 is supported by the corresponding porous support plate 132, and the catalyst modules 12 can be replaced during maintenance. The support cylinder 13 can be fixed to the reactor main body 11 as needed, or can be detachably connected to the reactor main body 11.

[0052] Each group of catalyst modules 12 includes one layer or at least two layers of catalyst brick layers stacked up and down. Each layer of catalyst brick layer includes a plurality of porous catalyst bricks 121 spliced with each other. The porous catalyst bricks 121 are block structures made of sintered catalyst with a plurality of through holes 122.

[0053] Each through hole 122 axially penetrates the catalyst brick up and down along the porous catalyst brick 121. When the number of layers of the catalyst brick layer is at least two layers, the through holes 122 of each layer of catalyst brick layer are arranged vertically opposite to each other. The ventilation holes on the porous support plate 132 can be of different shapes, such as round hole shape, square hole shape, or cross hole shape, etc., and it is ensured that the gas flow rate that can pass through the porous support plate 132 is greater than or equal to the gas flow rate that can pass through the catalyst module 12. Since the inside of the reactor main body 11 is a high-temperature environment, and there is a certain pressure between the multiple layers of catalyst brick layers stacked up and down, sintering the catalyst into a block structure can make the catalyst module 12 have sufficient strength, fill the entire cross-section of the reaction chamber, and ensure that it is not easy to deform during the catalytic process.

[0054] To ensure the catalytic efficiency of the catalyst for gases, this device uses a porous catalyst brick 121. The diameter of the through holes 122 of the porous catalyst brick 121 satisfies 5mm ≤ Φ ≤ 10mm, and the specific surface area is 500m 2 / m 3 .

[0055] The composition of the specific catalyst is determined according to actual needs. For example, in a specific embodiment, the composition of the porous catalyst brick 121 includes Al2O3, Ni, MgO, CaO, and BaO. It is a Ni / Al2O3 catalyst added with MgO, CaO, and BaO. The Ni / Al2O3 catalyst is a supported catalyst, with Ni as the supported active component and Al2O3 as the carrier. The added MgO is a basic carrier, and the content of MgO (weight content) is not less than 70%. Due to the strong interaction between nickel and the carrier and the basic characteristics of metal oxides, carbon formation during the dry reforming process can be well inhibited, especially the effect of MgO is very obvious. The catalyst is extruded, dried, and fired into a porous hexagonal brick, which is filled into the catalyst chamber of the reactor 1. The porous catalyst brick 121 prepared after sintering has a certain high-temperature strength, ensuring that it is not easily deformed and pulverized under high-temperature environments.

[0056] In addition, the number and cross-sectional shape of the specific reactor 1, the number of reaction chambers, the number of layers of the catalyst module 12 in the reaction chamber, and the height of the catalyst in the reaction chamber are determined according to actual needs. For example, in a specific embodiment, the entire device includes three reactors 1 arranged in parallel. The three reactors 1 share a set of raw gas inlet pipe 2 and reduction gas outlet pipe 4; the cross-section of the reactor main body 11 is square, the reactor main body 11 adopts a square pipe structure, and the diameter of the middle section of the reactor main body 11 is larger than the diameters of the inlet and outlet ports at both ends. There is a transition section (i.e., a conical section) between them, and the inclination angle range of the transition section is 20 - 30°. Each reaction chamber is located in the middle section of the reactor main body 11; there are two reaction chambers arranged at intervals up and down in the reactor main body 11. Each reaction chamber is provided with two groups of catalyst modules 12. The ratio of the total height of the catalyst in the lower reaction chamber (i.e., the first reaction chamber) to the pipe diameter (i.e., the diameter of the reactor main body 11) is 2 - 5:1, and the ratio of the total height of the catalyst in the upper reaction chamber (i.e., the second reaction chamber) to the pipe diameter is 4 - 8:1; to ensure the catalytic efficiency, the total height of the catalyst bricks filled in the first reaction chamber is not less than 3m, and the total height of the catalyst bricks filled in the second reaction chamber is not less than 3m.

[0057] As a preferred embodiment, referring to Figure 4 and Figure 5 , the shape of the porous catalyst brick 121 is a regular hexagonal block.

[0058] The number of holes in the general porous catalyst brick 121 (i.e., the number of through holes 122) is seven. The through holes 122 are round holes, and the hole diameter is, for example, 5 mm, and the hole pitch is, for example, 5 mm. One of the through holes 122 is located at the center of the porous catalyst brick 121, and the other six through holes 122 are arranged circumferentially and evenly spaced around the central through hole 122. A plurality of porous catalyst bricks 121 are neatly arranged in the support cylinder 13 and are closely joined together. The sides of each porous catalyst brick 121 are closely arranged with the corresponding sides of the adjacent porous catalyst bricks 121 to form a layer of catalyst brick layer that fills the cross-section of the support cylinder 13. For example, when the cross-section of the support cylinder 13 is square, the cross-section of one layer of catalyst brick layer is as Figure 4 shown; it can be understood that in order to adapt to the cross-section of the support cylinder 13, the porous catalyst bricks 121 located on the outer periphery will be cut, and the cross-section after cutting forms a part of a regular hexagon.

[0059] The porous catalyst brick 121 adopts a regular hexagonal block. The hexagonal structure enables the brick to evenly disperse the force in all directions when subjected to pressure, thereby improving the compressive capacity of the brick. The internal hole design and unique shape of the hexagonal porous brick can increase the surface area of the brick, increase the contact area between the catalyst and the raw material gas, and improve the catalytic efficiency. The hexagonal bricks can be closely arranged to achieve seamless splicing, reducing material waste and being more conducive to production and loading. In construction, this high material utilization rate not only reduces the usage of raw materials, but also reduces the cutting and processing workload during construction, further reducing costs.

[0060] Furthermore, in order to facilitate the replacement of the catalyst module 12, referring to Figure 6 , installation openings 111 are provided at the positions corresponding to each reaction chamber on the side wall of the reactor main body 11, and a baffle 14 is detachably and sealingly installed at the installation openings 111. When replacement is needed, the baffle 14 is opened, and after the catalyst module 12 is reloaded, the reaction chamber is sealed with the baffle 14 again. The replacement is simple, the operation is convenient, and time and cost are saved.

[0061] Further, a first water cooling channel is provided inside the side wall of the reactor main body 11. A first interface 112 and a second interface 113 communicating with the first water cooling channel are provided on the outer side wall of the reactor main body 11 and near the installation port 111. A second water cooling channel is provided inside the baffle 14, and a baffle water inlet 141 and a baffle water outlet 142 communicating with both ends of the first water cooling channel are provided on the outer side wall of the baffle 14. The baffle water inlet 141 and the baffle water outlet 142 can be connected to the first interface 112 and the second interface 113 respectively through a water inlet pipe and a water outlet pipe, and a water inlet valve 143 and a water outlet valve 144 are provided on the water inlet pipe and the water outlet pipe respectively. Cold water is used to be introduced into the first water cooling channel to cool the side wall of the reactor main body 11. It can be understood that a main body water inlet and a main body water outlet are also provided on the side wall of the reactor main body 11, communicating with both ends of the first water cooling channel respectively, to introduce cold water into the first water cooling channel. After the baffle 14 is hermetically installed into the corresponding installation port 111, the baffle water inlet 141 and the first interface 112 are connected through the water inlet pipe, and the baffle water outlet 142 is connected to the second interface 113 through the water outlet pipe, so that each baffle 14 and the reactor main body 11 share a set of water cooling circulation system.

[0062] Further, referring to Figure 1 , the flow guiding device 15 includes a rectifying grid 151 and a flow guiding plate assembly arranged at intervals up and down. The flow guiding plate assembly includes a plurality of vertical plates 152 arranged in parallel at intervals. The rectifying grid 151 is a uniform grid-like structure, and the plurality of vertical plates 152 are also evenly spaced, so as to play a better flow guiding role and make the air flow more uniform.

[0063] Optionally, gas analysis components 16 are provided above the reaction chamber at the top, below the reaction chamber at the bottom, and between adjacent two reaction chambers, for analyzing the temperature and components of the gas. Generally, the gas analysis component 16 located below the reaction chamber at the bottom is located below the flow guiding device 15 below this reaction chamber, and the gas analysis component 16 between adjacent two reaction chambers is located above the flow guiding device 15 between these two reaction chambers. By using each gas analysis component 16, the gas changes before and after the catalytic reaction can be measured better, and it is more conducive to detecting whether the components after catalysis meet the requirements of industrial production.

[0064] The gas analysis component 16 can, for example, include a temperature sensor and a gas analyzer (both existing devices), which are respectively used to detect the temperature of the gas and the composition of the gas. For another example, the gas analysis component 16 can also be an analysis system that continuously analyzes the gas composition online through a sampling probe, such as the SG-300 mobile high-temperature gas analysis system of Weisongli Company. This system consists of a high-temperature sampling probe that can be automatically moved into and out of the kiln and an online continuous gas analysis system, and is mainly applied to the detection of high-temperature kiln gases in cement rotary kilns or the online detection of gases in other high-temperature and high-dust industrial kilns, and can continuously and accurately detect the kiln gases (including SO2, CO, NO X , O2, CO2, CH4, water vapor, etc.) and the temperature inside the furnace.

[0065] Furthermore, referring to Figure 1 and Figure 7 , the first heat-exchanging gas heating device 3 includes a housing 31 arranged horizontally in the axial direction. Inside the housing 31, multiple heat-exchanging tubes 32 arranged horizontally in the axial direction are provided. The two ends of the heat-exchanging tubes 32 are respectively communicated with the two end faces of the housing 31 and are communicated with the raw material gas inlet pipe 2. A converter gas inlet 33 and a converter gas outlet 34 are provided on the side wall of the housing 31.

[0066] To improve the heat-exchanging effect, a plurality of first partition plates 35 and a plurality of second partition plates 36 are alternately arranged at intervals along the axial direction inside the housing 31. A gap is left between the lower end of the first partition plate 35 and the bottom side wall of the housing 31, and a gap is left between the upper end of the second partition plate 36 and the top side wall of the housing 31.

[0067] Furthermore, a second heat-exchanging gas heating device 5 is connected in series on the reducing gas outlet pipe 4. The structure of the second heat-exchanging gas heating device 5 is the same as that of the first heat-exchanging gas heating device 3. The two ends of the heat-exchanging tubes 32 of the second heat-exchanging gas heating device 5 are communicated with the reducing gas outlet pipe 4.

[0068] The housing 31 of the first heat-exchanging gas heating device 3 is connected in series in the raw material gas inlet pipe 2, and the housing 31 of the second heat-exchanging gas heating device 5 is connected in series in the reducing gas outlet pipe 4. During use, the raw material gas enters through the raw material gas inlet pipe 2 and then flows into each heat-exchanging tube 32, and exchanges heat with the converter gas introduced through the converter gas inlet 33 inside the housing 31 to heat the temperature of the raw material gas to the first preset target temperature (1000 - 1100 °C); the reducing gas obtained after being catalyzed by each reaction chamber in the reactor main body 11 enters each heat-exchanging tube 32 in the second heat-exchanging gas heating device 5 and exchanges heat with the converter gas introduced through the converter gas inlet 33 inside the housing 31 to heat the temperature of the reducing gas to the second preset target temperature (850 - 1050 °C). The staggered arrangement of the multiple first partition plates 35 and the multiple second partition plates 36 can make the heat-exchanging effect better.

[0069] Optionally, a flow guiding structure is further provided inside the raw material gas inlet pipe 2 and near the front end of the first heat exchange type gas heating device 3 (i.e., the left end in Figure 1 ). The flow guiding structure includes a plurality of flow guiding plates 23 to guide the gas so that it enters the heat exchange tubes 32 more uniformly.

[0070] Furthermore, a refractory material insulation layer is uniformly provided on the inner wall of the pipeline after the first heat exchange type gas heating device 3 to prevent heat dissipation of the device. That is, a refractory material insulation layer is provided on the inner wall of the raw material gas inlet pipe 2, the inner wall of the intake branch pipe 21, the inner wall of the reactor main body 11, the inner wall of the outlet branch pipe 41, and the inner wall of the reducing gas outlet pipe 4 after the first heat exchange type gas heating device 3.

[0071] Furthermore, the present application also provides a continuous catalytic reforming method. Using the above-mentioned continuous catalytic reforming device, the continuous catalytic reforming method includes:

[0072] Pass the raw material gas into the raw material gas inlet pipe 2 and exchange heat with converter gas in the first heat exchange type gas heating device 3 to heat the temperature of the raw material gas to a preset target temperature;

[0073] Pass the heat-exchanged raw material gas into at least one reactor 1 and react with the catalyst module 12 in each reaction chamber of the reactor 1 to obtain reducing gas;

[0074] The reducing gas is discharged through the reducing gas outlet pipe 4.

[0075] This method uses the above-mentioned continuous catalytic reforming device and has the same effect.

[0076] Furthermore, after obtaining the reducing gas, it further includes: exchanging heat between the reducing gas and converter gas to obtain reducing gas at a target temperature. Then the reducing gas is discharged for use in a gas-based shaft furnace.

[0077] This method mixes a certain proportion of converter gas, coke oven gas, and methane as the raw material gas, and uses the first heat exchange type gas heating device 3 to exchange heat with the raw material gas, so that the raw material gas can reach the target temperature (1000 - 1100 °C). The heated raw material gas is respectively passed into three reactors 1 for catalytic reforming reaction. The reformed reducing gas is collected into the reducing gas outlet pipe 4 through the upper outlet branch pipe 41, and then the reducing gas is used for the next step of gas-based shaft furnace use. The three catalytic reactors 1 can be used simultaneously, or in pairs, or individually. The gas flow rate in each individual reactor 1 is 10 - 20 m / s, and the gas flow rate in the raw material gas inlet pipe 2 is the sum of the gas flow rates in each reactor 1. The composition of the hydrogen-rich gas mixture in this method is: H2: 55 - 65%, CH4: 18 - 26%, CO ≤ 10%, total sulfur ≤ 1.0 mg / Nm3 。

[0078] Taking Figure 1 the structure shown as an example, a specific embodiment is used to describe the catalytic reforming reaction process of the present application in detail. The method includes the following steps:

[0079] S1. Confirm the gas flow rate and velocity, the filling height of catalyst bricks, and the size of the catalyst air permeability pore diameter in the continuous catalytic reforming device according to the subsequent process of the device (such as a gas-based shaft furnace); after confirming the process parameters, fill a certain height of catalyst bricks into each reaction chamber according to the process parameters. In this embodiment, the gas flow rate introduced into the raw material gas inlet pipe 2 is 50,000 Nm 3 / h, the flow velocity is 10 m / s. To ensure the catalytic efficiency, the total filling height of the catalyst bricks in the first reaction chamber is not less than 3 m, and the total filling height of the catalyst bricks in the second reaction chamber is not less than 3 m; the catalyst bricks used are porous catalyst bricks 121, with 7 catalyst pores, a pore diameter of 5 mm, a pore distance of 5 mm, and a specific surface area of 500 m 2 / m 3 。The catalyst bricks in the reaction chamber can be freely replaced. The catalyst bricks are neatly arranged in the reaction chamber. After the porous catalyst bricks 121 are replaced or filled, the installation opening 111 is closed using the baffle 14. The water-cooled circulating water of this baffle 14 is connected to the water-cooled outer shell (the side wall of the reaction body) of the reactor 1 through valves and pipelines, sharing a set of water-cooled circulating systems.

[0080] S2. After the catalyst is filled, according to the design result of the process parameters, a hydrogen-rich gas (for example, methane and carbon dioxide are mixed in a certain ratio, and the theoretical mixing ratio is 1:1) is introduced from the raw material gas inlet, and is heated to 1000 - 1100 °C in the first heat exchange gas heating device 3. The heated raw material gas is introduced into three reactors 1 or one of them or a combination of two according to the process design. The unused reactors 1 can be shut down by the valves at the bottom of the reactors 1.

[0081] S3. The raw material gas heated to the specified temperature passes through the first reaction chamber and the second reaction chamber in the reactor 1 respectively, and the raw material gas undergoes a catalytic reaction in the first reaction chamber and the second reaction chamber. Control the temperature range in the first reaction chamber and the second reaction chamber to be 900 - 950 °C. The catalyst used in the reaction is a specially prepared catalyst, and its main characteristics are: using porous catalyst bricks 121, an alkaline carrier (MgO content ≥ 70%), and the supported active component is Ni. A gas analysis component 16 is provided in the reactor 1, which can detect the temperature and composition of the raw material gas and the reformed gas after catalytic reduction, and can adjust the process parameters according to the detection results to improve the catalytic efficiency of the catalytic reaction reforming device. In the reforming reaction of methane in natural gas / coke oven gas and carbon dioxide in blast furnace top gas in the mixed gas:

[0082]

[0083] This device has a long service life and is easy to manufacture and process. It does not incur the cost of setting up traditional high-temperature tubular columns, reducing the manufacturing and maintenance costs of a single furnace body. At the same time, the composition of the reduced gas detected and output is CH4:CO2:H2:CO = 5.0%:5.0%:60.0%:30%, and the output temperature can reach 1100°C, meeting the requirements for using reduced gas in a gas-based shaft furnace. It can be seen that the reduction efficiency of the device is relatively high, with good feasibility and superiority.

[0084] In summary, for the entire device and method, the heat transfer efficiency is high, there is no need to stop production during maintenance, the service life is long, and it is easy to manufacture and process. This catalytic reforming device does not need to stop production during maintenance, ensuring continuous production; this device has a long service life and is easy to manufacture and process, eliminating the cost of setting up traditional high-temperature tubular columns and reducing the manufacturing and maintenance costs of a single furnace body. Through the reasonable layout of the structure of reactor 1, a stable region for high-temperature catalytic reforming reaction can be formed, and the stability of the reforming device is improved; this device adopts a tubular convection heat exchange method with high heat transfer efficiency, ensuring the full utilization of heat. At the same time, a second heat exchange type gas heating device 5 is provided at the reduced gas outlet, which can ensure the temperature of the outlet reduced gas, meet the quality and temperature requirements of the product gas, and continuously provide qualified reduced gas for the gas-based shaft furnace.

[0085] The above is only a schematic specific embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A continuous catalytic reforming device, characterized in that: include: A plurality of reactors, each of the reactors comprises a reactor body and at least two reaction chambers arranged in the reactor body and spaced apart from each other, each of the reaction chambers is provided with at least one group of catalyst modules, and a flow guide device is provided below each of the reaction chambers; A raw gas inlet pipe, the outlet end of which is connected to the gas inlet at the bottom of each reactor body in an on-off manner; A first heat exchange gas heating device is connected in series to the raw gas inlet pipe and is used for heat exchange between converter gas and raw gas to heat the raw gas to a preset target temperature; The reducing gas outlet pipe has an inlet end which is connected to the outlet port at the top of each reactor body in an on-off manner.

2. The continuous catalytic reforming device according to claim 1, characterized in that: In each of the reaction chambers, at least one support tube is provided with an opening at the top and a plurality of air holes at the bottom, and each group of the catalyst modules is filled in the corresponding support tube; each group of the catalyst modules includes one or at least two layers of catalyst bricks stacked up and down, and each layer of the catalyst bricks includes a plurality of porous catalyst bricks spliced ​​together, and the porous catalyst bricks are block structures made by sintering catalysts and having a plurality of through holes.

3. The continuous catalytic reforming device according to claim 2, characterized in that: The porous catalyst brick comprises Al2O3, Ni, MgO, CaO and BaO, and the content of MgO is ≥70%.

4. The continuous catalytic reforming device according to claim 2, characterized in that: The porous catalyst brick is a regular hexagonal block.

5. The continuous catalytic reforming device according to claim 1, characterized in that: An installation opening is provided on the side wall of the reactor body at a position corresponding to each reaction chamber, and a baffle is detachably and hermetically installed at the installation opening.

6. The continuous catalytic reforming device according to claim 5, characterized in that: A first water-cooling channel is provided in the side wall of the reactor body, and a first interface and a second interface connected to the first water-cooling channel are provided on the outer wall of the reactor body and close to the installation port; a second water-cooling channel is provided in the baffle, and a baffle water inlet and a baffle water outlet connected to both ends of the first water-cooling channel are provided on the outer wall of the baffle, the baffle water inlet and the baffle water outlet can be connected to the first interface and the second interface respectively through an inlet pipe and an outlet pipe, and an inlet valve and an outlet valve are provided on the inlet pipe and the outlet pipe respectively.

7. The continuous catalytic reforming device according to claim 1, characterized in that: The guide device comprises a rectifying grid and a guide plate assembly which are arranged in an up-and-down manner, and the guide plate assembly comprises a plurality of vertical plates which are arranged in a parallel manner.

8. The continuous catalytic reforming device according to claim 1, characterized in that: Gas analysis components are provided above the reaction chamber at the top, below the reaction chamber at the bottom, and between two adjacent reaction chambers for analyzing the temperature and components of the gas.

9. The continuous catalytic reforming device according to claim 1, characterized in that: The first heat exchange gas heating device includes an axially horizontally arranged shell, in which a plurality of axially horizontally arranged heat exchange tubes are arranged, and both ends of the heat exchange tubes are respectively connected to the two end surfaces of the shell and to the raw gas inlet pipe, and a converter gas inlet and a converter gas outlet are provided on the side wall of the shell.

10. The continuous catalytic reforming device according to claim 9, characterized in that: A plurality of first partitions and a plurality of second partitions are arranged in an interlaced manner along the axial direction of the shell, a gap is left between the lower end of the first partition and the bottom side wall of the shell, and a gap is left between the upper end of the second partition and the top side wall of the shell.

11. The continuous catalytic reforming device according to claim 1, characterized in that: A second heat exchange gas heating device is also connected in series to the reducing gas outlet pipe. The structure of the second heat exchange gas heating device is the same as that of the first heat exchange gas heating device. Both ends of the heat exchange pipe of the second heat exchange gas heating device are connected to the reducing gas outlet pipe.

12. A continuous catalytic reforming method, characterized in that: Using the continuous catalytic reforming device according to any one of claims 1 to 11, the continuous catalytic reforming method comprises: The raw gas is introduced into the raw gas inlet pipe, and is heat-exchanged with the converter gas in the first heat exchange gas heating device to heat the raw gas to a preset target temperature; Passing the heat-exchanged raw gas into at least one reactor, reacting with the catalyst module in each reaction chamber of the reactor to obtain a reducing gas; The reducing gas is discharged through the reducing gas outlet pipe.

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