Synthesis gas shift reactor and preparation device of feed gas for producing methanol

Abstract

The utility model belongs to the field of chemical equipment, and particularly relates to a synthesis gas shift reactor and a preparation device of feed gas for producing methanol. Heat exchange parts are arranged in the synthesis gas shift reactor and the isothermal reaction chamber; the heat exchange component exchanges heat with the heat exchange reaction chamber; the heat exchange component comprises a liquid medium heat exchange assembly and a gas medium heat exchange assembly; the gas medium heat exchange assembly is provided with a gas medium inlet and a gas medium outlet, and the gas medium outlet communicates with the gas inlet. According to the utility model, by arranging a subarea heat exchange mode in the upper-section isothermal reaction area, redundant heat generated by reaction is removed in time, so that the maximum utilization of energy is realized, and the overtemperature phenomenon in the adiabatic reactor is solved; by arranging a crude synthesis gas side inlet, special conditions such as different driving working conditions and load changes can be coped with; the adiabatic reaction section is additionally arranged at the lower part of the reactor, so that the outlet temperature of the reactor can be maintained at 400 DEG C or above, high-pressure saturated steam is superheated, and the utilization rate of energy is improved.

Description

Technical Field

[0001] The utility model belongs to the field of chemical equipment, and in particular relates to a synthesis gas conversion reactor and a preparation device for raw material gas used for producing methanol. Background Art

[0002] The CO shift process plays a crucial role in coal chemical industry. This process uses the crude synthesis gas produced by upstream coal gasification to react fully or partially to produce hydrogen over a catalyst, depending on the hydrogen-to-carbon ratio requirements of downstream products. For hydrogen and ammonia production, CO conversion is essential to the greatest extent possible. For methanol and natural gas production, the ratio of carbon monoxide to hydrogen in the synthesis gas must be adjusted based on product requirements.

[0003] Currently, the supporting shift processes for producing carbonyl synthesis gas from high-concentration carbon monoxide are generally divided into high water-gas ratio shift process, catalyst kinetic control shift process, and low water-gas ratio shift process. All three are adiabatic shift processes, in addition to isothermal shift process. The high water-gas ratio shift process suffers from energy waste, high equipment investment, and high operating costs; the catalyst kinetic control shift process requires high precision in calculating catalyst dosage; and the low water-gas ratio shift process is subject to problems such as methanation side reactions.

[0004] The high water-gas ratio shift process effectively prevents overheating of the shift furnace by adding excess steam to the shift furnace inlet, raising the water-gas ratio to 1.6 or even higher. However, excess steam also results in significant energy waste, and the excess steam condenses in the downstream low-grade heat recovery stage, requiring additional separation equipment, resulting in increased equipment investment and operating costs.

[0005] The catalyst kinetics-controlled shift process controls the catalyst loading to terminate the shift reaction before equilibrium is reached, thus preventing overheating of the catalyst bed in the shift furnace. Subsequent processes require additional boiler water based on the depth of the reaction, without the need for steam. However, when the shift process operates under conditions of high CO content and high water-gas ratio, the driving force of the reaction is high, leading to large temperature differences from equilibrium, necessitating precise calculation of catalyst dosage. Furthermore, when operating at low loads, a smaller amount of crude syngas can easily lead to overheating for the same catalyst loading.

[0006] The low-water-gas ratio shift process uses a low-pressure waste boiler installed before the shift unit to remove some water from the crude syngas, reducing the water-gas ratio to approximately 0.2. This significantly reduces the driving force of the shift reaction while maintaining a constant load, preventing overheating within the shift furnace while also producing high-grade steam as a byproduct. However, the low-water-gas ratio process involves a methanation side reaction, placing high demands on the catalyst.

[0007] To improve the adiabatic conversion process, isothermal conversion process technologies based on isothermal conversion furnaces have been developed in recent years. This involves installing a heat exchange unit within the catalyst bed of the conversion furnace to remove the heat released by the conversion reaction, effectively solving the problem of overheating within the conversion furnace. This process technology eliminates the need for pre-conversion furnaces, quenching lines, and other measures used to control overheating, simplifying the process. Furthermore, no steam is required during the conversion process, significantly saving equipment investment and operating costs. CN201410662794.8, "A Controllable Heat Transfer Reactor," proposes an axial isothermal reactor and its supporting processes; CN201510107191.6, "High-Concentration Carbon Monoxide Isothermal Conversion Process and System," proposes an axial isothermal reactor and its supporting processes. However, the steam produced as a by-product of this process is saturated steam, which is usually in large excess and has nowhere to be used. It does not have a wide range of utilization like superheated steam, and condensate will precipitate when the temperature is subsequently lowered, making it impossible to transport it through the pipeline network. In addition, when encountering changes in the upstream crude synthesis gas load, the water-gas ratio, and the need to increase the temperature of the catalyst at the end of the process, the outlet temperature of the conversion furnace needs to be adjusted frequently, so there is a certain degree of difficulty in controlling the removal of reaction heat.

[0008] At present, although the isothermal conversion process technology has improved most of the problems existing in the adiabatic conversion process, it also has some disadvantages. For example, the steam produced as a by-product of this process is saturated steam, which is usually in large quantities and has nowhere to be used. It does not have a wide range of utilization like superheated steam, and condensate will precipitate when the temperature is subsequently lowered, making it impossible to transport it through the pipeline network. In addition, when encountering changes in the upstream crude synthesis gas load, the water-gas ratio, and the need to increase the temperature of the catalyst at the end of the stage, the outlet temperature of the conversion furnace needs to be adjusted frequently, so there is a certain degree of difficulty in controlling the removal of reaction heat. Utility Model Content

[0009] In order to solve the problems encountered in the above-mentioned isothermal conversion process, the utility model provides a high-concentration carbon monoxide isothermal-adiabatic double radial conversion coupling technology for producing methanol. By setting a zoned heat exchange method in the upper isothermal reaction zone, the excess heat generated by the reaction is removed in time, energy is maximized, and the overheating phenomenon in the adiabatic reactor is solved; by setting a crude synthesis gas side inlet, special situations such as different start-up conditions and load changes can be coped with; by adding an adiabatic reaction section at the lower part of the reactor, the reactor outlet temperature can be maintained above 400°C, thereby superheating the high-pressure saturated steam and improving energy utilization.

[0010] A synthesis gas conversion reactor comprises a shell and a hollow cavity, wherein the shell is provided with a synthesis gas inlet and a conversion gas outlet; a partition is provided in the hollow cavity, and in the direction from the synthesis gas inlet to the conversion gas outlet, the partition divides the hollow cavity into an isothermal reaction zone and an adiabatic reaction zone; an isothermal reaction chamber is provided in the isothermal reaction zone; a heat exchange component is provided in the isothermal reaction chamber; the heat exchange component exchanges heat with the heat exchange reaction chamber; the heat exchange component comprises a liquid heat exchange component and a gas heat exchange component; the gas heat exchange component has a gas inlet and a gas outlet, and the gas outlet is connected to the synthesis gas inlet; an axially extending air duct I is provided in the center of the isothermal reaction chamber, and a plurality of gas collecting holes I are provided on the wall of the air duct I, the upper end of the air duct I is closed, and the lower end is connected to the adiabatic reaction zone.

[0011] As a preferred embodiment, the isothermal reaction chamber is mounted in a shell, and a gap is left between the side wall I of the isothermal reaction chamber and the inner wall of the shell as an air inlet channel I; a plurality of air vents I are provided on the side wall of the isothermal reaction chamber.

[0012] As a preferred embodiment, an adiabatic reaction chamber is provided in the adiabatic reaction zone, a gap II is left between the side wall II of the adiabatic reaction chamber and the inner wall of the shell, and a plurality of air vents II are provided on the side wall II; the air duct I, gap II, and air vents II are connected in sequence to form an air inlet channel II.

[0013] As a preferred embodiment, an air duct II is provided in the adiabatic reaction chamber, and a plurality of air collecting holes II are provided on the wall of the air duct II. The pipe opening of the air duct II close to one end of the air duct I is closed, and the pipe opening away from one end of the air duct I is connected to the conversion gas outlet.

[0014] As a preferred embodiment, the air guide pipe II extends axially and is located in the center of the adiabatic reaction chamber.

[0015] As a preferred embodiment, the synthesis gas inlet includes a first air inlet and a second air inlet; the second air inlet is connected to the central pipe; preferably, the first air inlet is located at the top of the shell, and the second air inlet is located in the middle of the shell.

[0016] As a preferred embodiment, the conversion gas outlet is located at the bottom of the housing.

[0017] As a preferred embodiment, in the isothermal reaction chamber, an isothermal reaction catalyst is filled between the side wall I and the air duct I; in the adiabatic reaction chamber, an adiabatic reaction catalyst is filled between the side wall II and the air duct II.

[0018] In the present invention, the isothermal reaction catalyst and the adiabatic reaction catalyst have different tolerance temperatures. The isothermal reaction catalyst can be a conventional catalyst, and the adiabatic reaction catalyst can be a high-temperature resistant catalyst with a tolerance temperature of up to 500°C.

[0019] As a preferred embodiment, a gas distributor is provided between the lower end of the gas guide pipe 1 and the adiabatic reaction zone.

[0020] As a preferred embodiment, the heat exchange component extends radially in the isothermal reaction chamber.

[0021] As a preferred embodiment, the liquid heat exchange assembly is composed of a plurality of liquid heat exchange plates; the liquid heat exchange assembly has a liquid inlet and a liquid outlet; preferably, each liquid heat exchange plate extends radially in the heat exchange reaction chamber; preferably, the plurality of liquid heat exchange plates are arranged in a central radial manner with the axial center of the heat exchange reaction chamber as the center.

[0022] As a preferred embodiment, the liquid heat exchange plate and the gas heat exchange plate are integrated into one; preferably, the gas heat exchange plate is close to the axial center of the heat exchange reaction chamber, and the liquid heat exchange plate is far away from the axial center of the heat exchange reaction chamber.

[0023] A process in which synthesis gas enters any of the above-mentioned synthesis gas shift reactors for a shift reaction, wherein the dry volume content of carbon monoxide in the synthesis gas is 30% to 90%. The volume ratio of water to absolute dry gas in the synthesis gas is 0.1 to 1.6. The pressure range of the synthesis gas is 1.0 to 9.0 MPaG. The gas temperature at the gas medium outlet is 150 to 350°C. The synthesis gas is composed of a first intake gas and a second intake gas; preferably, the intake volume of the first intake gas: the intake volume of the second intake gas = 10 to 80: the intake volume of the second intake gas = 30 to 100; preferably, the intake volume of the first intake gas: the intake volume of the second intake gas = 30 to 50: 40 to 80; more preferably, the first intake gas accounts for 40% of the raw gas: the second intake gas accounts for 60% of the raw gas.

[0024] The first inlet gas enters from the first inlet port, flows through the inlet channel and the vent I in sequence to enter the isothermal reaction chamber, and after the reaction, flows through the gas collecting hole I, the central tube, the distributor, the vent II in sequence to enter the adiabatic reaction chamber;

[0025] The second air enters from the second air inlet, flows through the central tube, the distributor, and the vent II in sequence to enter the adiabatic reaction chamber; after the synthesis gas in the adiabatic reaction chamber is reacted, it is discharged through the vent III and the conversion gas outlet in sequence.

[0026] The temperature of the gas discharged from the gas outlet is ≥400°C.

[0027] The utility model also provides a preparation device for raw gas for producing methanol, comprising any one of the above-mentioned synthesis gas conversion reactors, wherein the conversion gas generated by the synthesis gas conversion reactor is used as the raw gas for preparing methanol.

[0028] As a preferred embodiment, the raw gas preparation device further includes a high-pressure steam superheater, a high-pressure steam generator, a high-pressure water preheater, a first low-pressure steam superheater and a first low-pressure steam generator; the synthesis gas shift reactor, the high-pressure steam superheater, the high-pressure steam generator, the high-pressure water preheater, the low-pressure steam superheater and the low-pressure steam generator are connected in sequence; the high-pressure steam superheater 4 has a pipe I-1 and a pipe I-2 for mutual heat exchange; the high-pressure steam generator 5 has a pipe II-1 and a pipe II-2 for mutual heat exchange; the high-pressure water preheater 6 has a pipe II-1 and a pipe II-2 for mutual heat exchange; The heat exchange pipeline III-1 and pipeline III-2; the first low-pressure steam superheater 7 has pipeline IV-1 and pipeline IV-2 for mutual heat exchange; the first low-pressure steam generator 8 has pipeline V-1 and pipeline V-2 for mutual heat exchange; the conversion gas outlet of the synthesis gas conversion reactor, pipeline I-1, pipeline II-1, pipeline III-1, pipeline IV-1 and pipeline V-1 are connected in sequence; the high-pressure water supply end, pipeline III-2, pipeline II-2 and pipeline I-2 are connected in sequence, and the low-pressure water supply end is connected to pipeline V-2 and pipeline IV-2 in sequence.

[0029] Preferably, the high-pressure water supply is also connected to pipeline III-2 and the liquid medium inlet. After flowing through pipeline III-2 of the high-pressure water preheater, the high-pressure water is split into two streams: one stream flows into pipeline II-2 of the high-pressure steam generator, and the other stream flows into the liquid medium inlet of the synthesis gas shift reactor.

[0030] As a preferred embodiment, the feed gas preparation apparatus further includes a first gas-liquid separator, a first detoxification tank, and a second low-pressure steam generator; the second low-pressure steam generator 9 has pipelines VI-1 and VI-2 for heat exchange; the gas phase outlet of the first gas-liquid separator, the first detoxification tank, and the synthesis gas shift reactor are sequentially connected; and the low-pressure water supply end is also sequentially connected to pipelines VI-2 and IV-2. The low-pressure water is split into two streams, one of which flows sequentially into pipeline V-2 of the first low-pressure steam generator and pipeline IV-2 of the first low-pressure steam superheater, and the other flows sequentially into pipeline VI-2 of the second low-pressure steam generator and pipeline IV-2 of the first low-pressure steam superheater.

[0031] As a preferred embodiment, the gas outlet of the first gas-liquid separator is also connected to pipeline VI-1. The crude synthesis gas separated by the first gas-liquid separator is separated into two gas phases, one of which enters the synthesis gas shift reactor and the other enters pipeline VI-1 of the second low-pressure steam generator.

[0032] As a preferred embodiment, the feed gas preparation apparatus further includes a second gas-liquid separator, a second detoxification tank, and a waste heat recovery unit; the gas phase outlet of the first gas-liquid separator, pipeline VI-1, and the second gas-liquid separator are sequentially connected; the gas phase outlet of the second gas-liquid separator is connected to the second detoxification tank and the waste heat recovery unit; and pipeline V-1 of the first low-pressure steam generator is connected to the waste heat recovery unit. The gas phase obtained after separation of the crude syngas in the first gas-liquid separator is split into two streams: one stream enters the syngas shift reactor, and the other stream flows through pipeline VI-1 of the second low-pressure steam generator and enters the second gas-liquid separator.

[0033] The first gas-liquid separator and the second gas-liquid separator in the utility model are used to separate saturated water that may be carried in the crude synthesis gas and to play a buffering role. No specific separation conditions are required. The operating pressure of the separators is the same as the pressure range of the crude synthesis gas, 1.0 to 9.0 MPaG.

[0034] The first detoxification tank and the second detoxification tank of the utility model are conventional containers in the field, which are filled with porcelain balls or catalysts and are used to purify crude synthesis gas.

[0035] The advantages of the process technology provided by the utility model are:

[0036] (1) By setting up a side inlet for crude synthesis gas, special situations such as different start-up conditions and load changes can be dealt with.

[0037] (2) By setting up zoned heat exchange in the upper isothermal reaction zone, the crude synthesis gas is preheated in the secondary catalyst zone, and high-pressure saturated steam is generated in the primary catalyst zone, so as to immediately remove the excess heat generated by the conversion reaction and avoid overheating; at the same time, the crude synthesis gas can be preheated to the catalyst activation temperature and high-pressure saturated steam can be produced as a by-product. The former avoids the problem of tube sheet leakage caused by excessive temperature difference on the shell and tube side of the crude synthesis gas preheater in the past. Directly removing the preheater can also reduce the complexity of the process and equipment investment. The latter maximizes the utilization of energy by producing high-pressure saturated steam as a by-product.

[0038] (3) An adiabatic reaction section is set at the bottom of the reactor, so that the final conversion gas outlet temperature reaches above 400°C, and superheated high-pressure steam is produced as a by-product, saving equipment investment and operating costs.

[0039] (4) The conversion gas after the by-product superheated high-pressure steam can also be used to superheat low-pressure saturated steam, reduce the production of low-pressure saturated steam with lower utilization value, and maximize energy utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Process flow chart;

[0041] Figure 2 The external furnace structure of the radially isothermal and axially adiabatic double conversion coupled reactor;

[0042] Figure 3 Internal structure of radially isothermal and axially adiabatic double conversion coupled reactor;

[0043] Figure 4 Partial schematic diagram of heat exchange components (collection ring);

[0044] Figure 5 Partial schematic diagram of heat exchange components (collecting ball);

[0045] In the figure, 1 is a first gas-liquid separator, 2 is a first detoxification tank, 3 isothermal-adiabatic double radial conversion coupling reactor, 4 isothermal gas high-pressure steam superheater, 5 isothermal gas high-pressure steam generator, 6 isothermal gas high-pressure boiler water preheater, 7 isothermal gas low-pressure steam superheater, 8 isothermal gas low-pressure steam generator, 9 isothermal gas low-pressure steam generator, 10 isothermal gas-liquid separator, 11 isothermal detoxification tank, 12 isothermal heat recovery unit;

[0046] 100 furnace body; 101 catalyst upper discharge port, 102 catalyst lower discharge port;

[0047] 201 first high-pressure boiler water inlet, 202 second high-pressure boiler water inlet;

[0048] 301 first high-pressure saturated steam outlet, 302 second high-pressure saturated steam outlet;

[0049] 401 first crude synthesis gas preheating outlet, 402 second crude synthesis gas preheating outlet;

[0050] 50: Main inlet for crude synthesis gas; 70: Main inspection port; 90: Side inlet for crude synthesis gas;

[0051] 601 first crude synthesis gas preheating inlet, 602 second crude synthesis gas preheating inlet;

[0052] 11 conversion gas outlet, 12 expansion joint, 13 high-pressure saturated steam collecting ring, 14 high-pressure saturated steam riser, 15 preheating crude synthesis gas collecting ring, 16 preheating crude synthesis gas riser, 17 catalyst tube, 18 heat exchange strengthening plate, 19 center pipe, 20 high-pressure boiler water riser, 21 high-pressure boiler water collecting ring, 22 crude synthesis gas riser, 23 crude synthesis gas collecting ball, 24 upper inspection port, 25 collecting ball inspection port, 26 gas distributor, 27 pressure grid, 28 lower inspection port, 29 catalyst, 30 porcelain ball, gas medium heat exchange plate 200, water medium heat exchange plate 210. DETAILED DESCRIPTION

[0053] The following are only preferred implementation methods of the present invention and are not intended to limit the scope of protection of the present invention. All technical solutions based on the concept of the present invention should fall within the scope of protection of the present invention. For professional and technical personnel in this technical field, minor improvements to the present invention without departing from the principles of the present invention should also fall within the scope of protection of the present invention.

[0054] In the preparation examples, embodiments and comparative examples of the present invention, unless otherwise specified, the components and pipe fittings used are commercially available products.

[0055] In response to the problems of the prior art, the utility model provides a high-concentration carbon monoxide isothermal-adiabatic double radial conversion coupling process technology for producing methanol, which can quickly and effectively adjust the conversion gas temperature, produce superheated high-pressure steam as a by-product, preheat the crude synthesis gas, reduce the output of low-pressure saturated steam with lower utilization value, and reduce investment and operation difficulty.

[0056] The technical solution adopted by the utility model to solve the above technical problems is: a high-concentration carbon monoxide isothermal-adiabatic double radial transformation coupling process technology for producing methanol.

[0057] The overall process of the high-concentration carbon monoxide isothermal-adiabatic dual radial conversion coupling process for producing methanol is as follows: the crude synthesis gas from upstream gasification first enters the first gas-liquid separator 1 to separate excess saturated water therein, and the crude synthesis gas after water separation is divided into mainstream crude synthesis gas (conversion line) and bypass crude synthesis gas (non-conversion line), with the conversion line flow rate: non-conversion line flow rate = 3:1.

[0058] The mainstream crude synthesis gas enters the detoxification tank 2 to remove impurities and components that are easy to poison the catalyst. The purified crude synthesis gas is divided into two streams, 60% entering from the crude synthesis gas main inlet 50 and 40% entering from the crude synthesis gas side inlet 90. The crude synthesis gas enters the adiabatic-isothermal double radial conversion coupling reactor 3 for preheating (reaching the catalyst activation temperature of 197°C). The preheated crude synthesis gas flows out from the crude synthesis gas preheating outlet, enters the upper isothermal reaction zone through the top of the adiabatic-isothermal double radial conversion coupling reactor for conversion reaction, and the converted gas coming out is mixed with the crude synthesis gas entering from the crude synthesis gas side inlet, and enters the lower adiabatic reaction zone together for conversion reaction. Finally, the conversion gas flowing out from the bottom of the adiabatic-isothermal double radial conversion coupling reactor is sequentially subjected to the conversion gas high-pressure steam. Steam superheater 4 (superheats high-pressure saturated steam, with a steam superheat of 30°C), conversion gas high-pressure steam generator 5 (exchanges heat from high-pressure boiler water to saturated steam, with a high-pressure saturated steam pressure of 4.0 MPaG), conversion gas high-pressure boiler water preheater 6 (preheats high-pressure boiler water to 150°C), conversion gas low-pressure steam superheater 7 (superheats low-pressure saturated steam to 30°C), conversion gas low-pressure steam generator 8 (exchanges heat from low-pressure boiler water to low-pressure saturated steam, with a low-pressure saturated steam pressure of 0.45 MPaG).

[0059] The bypass crude synthesis gas enters the non-conversion gas low-pressure steam generator 9 and exchanges heat with the low-pressure boiler water, and then enters the second detoxification tank for detoxification.

[0060] The shift gas flowing out of the shift gas low-pressure steam generator is mixed with the bypass crude synthesis gas that has undergone heat exchange and detoxification, so that the proportion of each component in the mixed shift gas meets the standard of downstream methanol production, and then sent to the subsequent waste heat recovery section, which mainly recycles and reuses heat through desalted water, boiler water, and low-pressure saturated steam.

[0061] The interior of the adiabatic-isothermal dual radial conversion coupled reactor is divided into two sections, upper and lower. In the upper section, the catalyst cartridge is sleeved within the furnace body, and a synthesis gas outlet channel is formed between the catalyst cartridge and the furnace body. The central tube extends from the main inlet of the crude synthesis gas to the bottom of the catalyst cartridge. The central tube and the side walls of the catalyst cartridge are respectively provided with outer and inner air inlet annular gaps. The area between the catalyst cartridge and the central tube is called the reaction zone. The partitioned catalyst is loaded in this area, and the catalyst can be discharged through the catalyst upper discharge port at the lower end of the reaction zone. In order to maintain the upper reaction zone in an isothermal state and simultaneously preheat the crude synthesis gas to the catalyst activation temperature and by-product high-pressure saturated steam, the present invention sets up a partitioned heat exchange in the reaction zone. The crude synthesis gas is preheated in the secondary catalyst partition, and the high-pressure saturated steam is generated in the primary catalyst partition. Therefore, the two partitions of the upper reaction zone of the reactor of the present invention are provided with multiple plate cooling units.

[0062] The cooling unit is a plate-type heat exchange unit. Within the reaction zone, the plate cooling unit is arranged radially from the center of the reaction zone, with the central tube as the axis. The plate cooling unit has multiple raised areas on its side. This arrangement increases the turbulence of the fluid, thereby improving the heat transfer coefficient. Furthermore, with the same amount of heat transfer, the required heat exchange area is smaller, significantly reducing equipment investment. The inlet of the plate cooling unit within the first catalyst zone is connected to the high-pressure boiler water riser. Multiple high-pressure boiler water risers converge and connect to a high-pressure boiler water collection ring, which is connected to the high-pressure boiler water inlet. The inlet of the plate cooling unit within the second catalyst zone is connected to the crude synthesis gas riser. Multiple crude synthesis gas risers converge and connect to a crude synthesis gas collection ball, which is connected to the crude synthesis gas preheating inlet. In addition, a collection ball inspection port is provided below the collection ball for maintenance purposes. The outlets of the plate cooling units in the first-level partition of the catalyst are all connected to the high-pressure saturated steam riser, and multiple high-pressure saturated steam risers are gathered in the high-pressure saturated steam collecting ring. At the same time, the upper part of the high-pressure saturated steam collecting ring is connected to the high-pressure saturated steam outlet to send out the steam; the outlets of the plate cooling units in the second-level partition of the catalyst are all connected to the preheated crude synthesis gas riser, and multiple preheated crude synthesis gas risers are gathered in the preheated crude synthesis gas collecting ring. At the same time, the upper part of the preheated crude synthesis gas collecting ring is connected to the crude synthesis gas preheating outlet to send out the preheated crude synthesis gas.

[0063] A crude syngas inlet is located between the upper and lower sections of the furnace. Syngas from the bypass is directly mixed with the shifted gas flowing from the upper central tube, then passes through a gas distributor and enters the lower adiabatic reaction section. Bypass regulation allows for optimal control of the shifted gas outlet temperature at the lower end, accommodating varying startup conditions and load variations.

[0064] The lower end of the furnace body houses a drum-type mixing and radial adiabatic reactor. Reaction gases pass radially through the shift catalyst bed from both sides, reacting before exiting through the shift gas outlet. The adiabatic reaction section allows the shift gas outlet temperature to reach over 400°C, allowing it to superheat high-pressure saturated steam. Catalyst in the adiabatic section is discharged through the catalyst lower discharge port.

[0065] The crude synthesis gas from upstream gasification has a carbon monoxide dry volume content of 30-90%, a water / absolute dry gas volume ratio of 0.1-1.6, and a pressure range of 1.0-9.0 MPaG.

[0066] The pressure range of the superheated steam produced as a by-product of the conversion gas high-pressure steam superheater and the saturated steam produced as a by-product of the conversion gas high-pressure steam generator is 2.5~8.0MPaG, and the pressure range of the superheated steam produced as a by-product of the conversion gas low-pressure steam superheater and the saturated steam produced as a by-product of the conversion gas low-pressure steam generator is 0.1~2.5MPaG.

[0067] The outlet temperature of the crude synthesis gas flowing out of the crude synthesis gas preheating outlet is 150-350°C.

[0068] The waste heat recovery unit includes waste heat recovery equipment such as a shift gas desalted water preheater, a shift gas water cooler, a stripping tower, etc., which can utilize waste heat multiple times to achieve multi-level energy utilization.

[0069] Example 1

[0070] like Figure 1 As shown, Example 1 is a high-concentration carbon monoxide isothermal-adiabatic dual radial coupled conversion process for producing methanol. The equipment and units involved in this process include: a first gas-liquid separator 1, a first detoxification tank 2, an isothermal-adiabatic dual radial conversion coupling reactor 3, a conversion gas high-pressure steam superheater 4, a conversion gas high-pressure steam generator 5, a conversion gas high-pressure boiler water preheater 6, a conversion gas low-pressure steam superheater 7, a conversion gas low-pressure steam generator 8, a non-conversion gas low-pressure steam generator 9, a second gas-liquid separator (non-conversion gas separator) 10, a second detoxification tank 11, and a waste heat recovery unit 12.

[0071] like Figure 2 、 Figure 3 The equipment structure of this embodiment 1 includes: a furnace body 100, a first high-pressure boiler water inlet 201, a second high-pressure boiler water inlet 202, a first high-pressure saturated steam outlet 301, a second high-pressure saturated steam outlet 302, a first crude synthesis gas preheating outlet 401, a second crude synthesis gas preheating outlet 402, a crude synthesis gas main inlet 50, a first crude synthesis gas preheating inlet 601, a second crude synthesis gas preheating inlet 602, main inspection ports 70, 101, a catalyst upper discharge port, a crude synthesis gas side inlet 90, and a catalyst lower discharge port 1 02, conversion gas outlet 11, expansion joint 12, high-pressure saturated steam collecting ring 13, high-pressure saturated steam riser 14, preheating crude synthesis gas collecting ring 15, preheating crude synthesis gas riser 16, catalyst tube 17, heat exchange strengthening plate 18, center pipe 19, high-pressure boiler water riser 20, high-pressure boiler water collecting ball 21, crude synthesis gas riser 22, crude synthesis gas collecting annular gap 23, upper inspection port 24, collecting ball inspection port 25, gas distributor 26, pressure grid 27, lower inspection port 28, catalyst 29, porcelain ball 30.

[0072] like Figure 4As shown, a heat exchange enhancement plate 18 is provided in the isothermal reaction chamber for promptly removing the reaction heat in the isothermal reaction chamber. The heat exchange enhancement plate 18 is composed of a number of dual-channel heat exchange plates. Each dual-channel heat exchange plate is integrated with a single liquid heat exchange plate and a single gas heat exchange plate. The dual-channel heat exchange plates are arranged in a central radial pattern. The gas heat exchange plate 200 is close to the central tube 19, and the water heat exchange plate 210 is far away from the central tube 19. The water heat exchange plate 210 circulates a water source (preferably boiler water) as a heat exchange medium, and the gas heat exchange plate 200 circulates the raw synthesis gas to be preheated as a heat exchange medium. In addition, as Figure 5 As shown, the high-pressure boiler water collecting ring can also be replaced by a high-pressure boiler water collecting ball.

[0073] The isothermal-adiabatic double radial shift coupled reactor is divided into two systems, namely a two-stage double radial shift reaction system and a steam generation and crude synthesis gas preheating system.

[0074] The process flow of the two-stage dual radial shift reaction system is as follows: Raw crude syngas enters the furnace body 100 through the crude syngas main inlet 50 and then flows radially through the outer inlet annular gap toward the central tube 19. The crude syngas reacts with the catalyst in the reaction zone of the catalyst cartridge 17 (a conventional catalyst is used for the isothermal reaction) while simultaneously exchanging heat with the heat exchange enhancement plate 18. Excess heat is removed by the high-pressure boiler water and crude syngas feed in the heat exchange enhancement plate 18, preventing overheating in the reaction zone. The resulting shifted gas flows out through the inner inlet annular gap and into the gas flow channel. The outflowing shifted gas mixes with the crude syngas entering the crude syngas side inlet 90, passes through the gas distributor 26, and enters the lower adiabatic reaction zone in a uniform distribution. It then flows radially from both sides into the catalyst 29 for the shift reaction (a high-temperature resistant catalyst with a maximum temperature tolerance of 500°C). The resulting shifted gas passes through the annular gap into the central tube 19 of the lower reactor section, reaching a temperature above 400°C, and is discharged through the shifted gas outlet 11.

[0075] The furnace body 100 is equipped with an upper catalyst discharge port 101 for loading and unloading catalyst from the upper isothermal reaction zone; a lower catalyst discharge port 102 for loading and unloading catalyst from the lower adiabatic reaction zone. A main access port 70 allows maintenance personnel to enter the reactor interior, while an upper access port 24 and a lower access port 28 allow maintenance personnel to access the upper and lower areas of the reactor, respectively. Porcelain balls 30 are also arranged within the furnace body 100 to protect and support the catalyst 29 and the catalyst bed in the upper isothermal reaction zone. A pressure grid 27 secures the catalyst 29 and porcelain balls 30. A gas distributor 26 distributes and mixes the reaction gases.

[0076] The steam generation system operates as follows: external high-pressure boiler water flows through the first high-pressure boiler water inlet 201 and the second high-pressure boiler water inlet 202, converges at the high-pressure boiler water collecting ring 21, and then enters the water-medium heat exchange plate 210 through the high-pressure boiler water riser 20. The high-pressure boiler water absorbs excess heat in the water-medium heat exchange plate 210 to prevent the catalyst from overheating. After absorbing heat, the high-pressure boiler water forms high-pressure saturated steam, flows out of the outlet of the water-medium heat exchange plate 210, enters the high-pressure saturated steam riser 14, converges at the high-pressure saturated steam collecting ring 13, and then flows out from the first high-pressure saturated steam outlet 301 and the second high-pressure saturated steam outlet 302. The external crude synthesis gas passes through the first crude synthesis gas preheating inlet 601 and the second crude synthesis gas preheating inlet 602, and is collected in the crude synthesis gas collecting ball 23, and then enters the gas-medium heat exchange plate 200 through the crude synthesis gas riser 22. The crude synthesis gas absorbs excess heat in the gas-medium heat exchange plate 200 to prevent the catalyst from overheating. After absorbing heat, the temperature of the crude synthesis gas reaches the catalyst activation temperature, flows out from the outlet of the gas-medium heat exchange plate 200 and enters the preheating crude synthesis gas riser 16 to be collected in the preheating crude synthesis gas collecting ring 15, and then flows out from the first crude synthesis gas preheating outlet 401 and the second crude synthesis gas preheating outlet 402.

[0077] The high-concentration carbon monoxide isothermal-adiabatic dual radially coupled conversion process for producing methanol includes the following steps: Crude syngas from a quenched pulverized coal gasification unit is fed at a temperature of 197°C, a pressure of 3.60 MPaG, a carbon monoxide content of 70% on a dry basis, and a water-gas ratio of 0.93. The crude syngas first enters a first gas-liquid separator (1). Process condensate flows out of the bottom outlet of the first gas-liquid separator, while the top outlet of the separator removes excess moisture from the crude syngas, which is then divided into a main stream and a bypass stream. The mainstream crude syngas enters the first detoxification tank 3 to remove impurities and components that easily deactivate the catalyst. The majority of the crude syngas then enters the upper isothermal reaction zone of the isothermal-adiabatic dual radial shift coupling reactor 3 through the first and second crude syngas preheating inlets 601 and 602 for preheating. It then flows out through the first and second crude syngas preheating outlets 401 and 402. The preheated crude syngas enters the upper isothermal reaction zone of the isothermal-adiabatic dual radial shift coupling reactor 3 through the crude syngas main inlet 50 for shift reaction. A first high-pressure boiler water inlet 201, a second high-pressure boiler water inlet 202, a first high-pressure saturated steam outlet 301, and a second high-pressure saturated steam outlet 302 are provided on the side of the isothermal-adiabatic dual radial shift coupling reactor 3. These outlets utilize the high-pressure boiler water to remove excess heat from the upper isothermal reaction zone, while also producing high-pressure saturated steam as a byproduct. The conversion gas coming out of the upper isothermal zone is mixed with a small amount of crude synthesis gas entering from the crude synthesis gas side inlet, and enters the adiabatic reaction zone of the lower section together for another conversion reaction. The conversion gas coming out of the conversion gas outlet 11 passes through the conversion gas high-pressure steam superheater 4, the conversion gas high-pressure steam generator 5, the conversion gas high-pressure boiler water preheater 6, the conversion gas low-pressure steam superheater 7, and the conversion gas low-pressure steam generator 8 in sequence, and respectively produces 3.75MPaG high-pressure superheated steam as a by-product, exchanges high-pressure boiler water into saturated steam, preheats high-pressure boiler water, produces 0.52MPaG low-pressure superheated steam as a by-product, and exchanges low-pressure boiler water into low-pressure saturated steam. The raw synthesis gas from the bypass stream coming out of the top of the first gas-liquid separator 1 passes through the non-conversion gas low-pressure steam generator 9, the non-conversion gas separator 10 (the operating pressure of the second gas-liquid separator is 3.5 MPaG, ranging from 1.0 to 9.0 MPaG. The temperature is 60°C, ranging from 30 to 200°C), and the second detoxification tank 11 in sequence, which respectively heat the low-pressure boiler water into low-pressure saturated steam, discharge the excess water in the raw synthesis gas from the bypass stream in the form of condensate, and remove impurities and components that are easy to poison the catalyst from the raw synthesis gas from the bypass stream. Finally, the conversion gas flowing out of the conversion gas low-pressure steam generator 8 is mixed with the raw synthesis gas flowing out of the second detoxification tank 11 and enters the subsequent waste heat recovery unit 12. The waste heat recovery unit 12 is equipped with a conversion gas desalted water preheater (not shown in the figure), a conversion gas water cooler (not shown in the figure), a stripping tower (not shown in the figure) and other equipment to fully utilize the waste heat.

Claims

1. Synthesis gas shift reactor, characterized in that The invention comprises a shell and a hollow cavity, wherein the shell is provided with a synthesis gas inlet and a conversion gas outlet; a partition is provided in the hollow cavity, and in the direction from the synthesis gas inlet to the conversion gas outlet, the partition divides the hollow cavity into an isothermal reaction zone and an adiabatic reaction zone; An isothermal reaction chamber is provided in the isothermal reaction zone; A heat exchange component is provided in the isothermal reaction chamber; the heat exchange component exchanges heat with the heat exchange reaction chamber; The heat exchange component includes a liquid heat exchange component and a gas heat exchange component; the gas heat exchange component has a gas inlet and a gas outlet, and the gas outlet is connected to the synthesis gas inlet; In the center of the isothermal reaction chamber, an axially extending air guide pipe I is provided. The wall of the air guide pipe I is provided with a plurality of air collecting holes I. The upper end of the air guide pipe I is closed, and the lower end is connected to the adiabatic reaction zone.

2. The synthesis gas shift reactor according to claim 1, characterized in that The isothermal reaction chamber is sleeved in the shell, and a gap is left between the side wall I of the isothermal reaction chamber and the inner wall of the shell, which serves as an air inlet channel I; the side wall of the isothermal reaction chamber is provided with a plurality of vent holes I; And / or, an adiabatic reaction chamber is provided in the adiabatic reaction zone, a gap II is left between a side wall II of the adiabatic reaction chamber and an inner wall of the shell, and a plurality of vents II are provided on the side wall II; the air guide pipe I, the gap II, and the vents II are sequentially connected to form an air inlet channel II; An air duct II is provided in the adiabatic reaction chamber, and a plurality of air collecting holes II are provided on the wall of the air duct II. The pipe opening of the air duct II close to one end of the air duct I is closed, and the pipe opening away from one end of the air duct I is connected to the conversion gas outlet.

3. The synthesis gas shift reactor according to claim 2, characterized in that The air guide pipe II extends axially and is located in the center of the adiabatic reaction chamber; The synthesis gas inlet includes a first air inlet and a second air inlet; the second air inlet is connected to the central pipe; the first air inlet is located at the top of the shell, and the second air inlet is located in the middle of the shell; and / or, the conversion gas outlet is located at the bottom of the shell; In the isothermal reaction chamber, an isothermal reaction catalyst is filled between the side wall I and the air guide pipe I; in the adiabatic reaction chamber, an adiabatic reaction catalyst is filled between the side wall II and the air guide pipe II.

4. The synthesis gas shift reactor according to claim 3, characterized in that A gas distributor is provided between the lower end of the gas guide pipe 1 and the adiabatic reaction zone.

5. The synthesis gas shift reactor according to claim 4, characterized in that The heat exchange component extends radially in the isothermal reaction chamber; And / or, the liquid heat exchange assembly is composed of a plurality of liquid heat exchange plates; the liquid heat exchange assembly has a liquid inlet and a liquid outlet; each liquid heat exchange plate extends radially in the heat exchange reaction chamber; and the plurality of liquid heat exchange plates are arranged in a central radial pattern with the axial center of the heat exchange reaction chamber as the center.

6. The synthesis gas shift reactor according to claim 5, characterized in that The liquid heat exchange plate and the gas heat exchange plate are integrated into one; the gas heat exchange plate is close to the axial center of the heat exchange reaction chamber, and the liquid heat exchange plate is far away from the axial center of the heat exchange reaction chamber.

7. A device for preparing raw gas for producing methanol, characterized in that: It comprises the synthesis gas shift reactor described in any one of claims 1-6.

8. The raw gas preparation device according to claim 7, characterized in that: The raw gas preparation device further includes a high-pressure steam superheater, a high-pressure steam generator, a high-pressure water preheater, a first low-pressure steam superheater and a first low-pressure steam generator; The synthesis gas shift reactor, the high-pressure steam superheater, the high-pressure steam generator, the high-pressure water preheater, the low-pressure steam superheater and the low-pressure steam generator are connected in sequence; The high-pressure steam superheater has a pipeline I-1 and a pipeline I-2 for exchanging heat with each other; The high-pressure steam generator has a pipeline II-1 and a pipeline II-2 for heat exchange with each other; The high-pressure water preheater has pipeline III-1 and pipeline III-2 for heat exchange with each other; The first low-pressure steam superheater has pipes IV-1 and IV-2 for heat exchange. The first low-pressure steam generator has a pipeline V-1 and a pipeline V-2 for heat exchange with each other; The shift gas outlet of the syngas shift reactor, pipeline I-1, pipeline II-1, pipeline III-1, pipeline IV-1 and pipeline V-1 are connected in sequence; The high-pressure water supply end, pipeline III-2, pipeline II-2 and pipeline I-2 are connected in sequence; The high-pressure water supply end is also connected to pipeline III-2 and the liquid medium inlet in sequence; The low-pressure water supply end is connected to pipeline V-2 and pipeline IV-2 in sequence.

9. The raw gas preparation device according to claim 8, characterized in that: The raw gas preparation device further includes a first gas-liquid separator, a first detoxification tank and a second low-pressure steam generator; The second low-pressure steam generator has a pipeline VI-1 and a pipeline VI-2 for heat exchange with each other; The gas phase outlet of the first gas-liquid separator, the first detoxification tank, and the synthesis gas shift reactor are connected in sequence; The low-pressure water supply end is also connected to pipeline VI-2 and pipeline IV-2 in sequence; The gas outlet of the first gas-liquid separator is also connected to pipeline VI-1.

10. The raw gas preparation device according to claim 9, characterized in that: The raw gas preparation device further includes a second gas-liquid separator, a second detoxification tank and a waste heat recovery unit; The gas phase outlet of the first gas-liquid separator, pipeline VI-1, and the second gas-liquid separator are connected in sequence; The gas phase outlet of the second gas-liquid separator is connected to the second detoxification tank and the waste heat recovery unit; The pipeline V-1 of the first low-pressure steam generator is connected to the waste heat recovery unit.

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