CN113457581A

CN113457581A - Fixed bed reactor for Fischer-Tropsch synthesis

Info

Publication number: CN113457581A
Application number: CN202110861806.XA
Authority: CN
Inventors: 孙启文; 颜芳; 张宗森; 刘继森; 董良; 滕强; 崔格瑞; 秦其智
Original assignee: Shanghai Yankuang Energy Technology R & D Co ltd
Current assignee: Shanghai Yankuang Energy Technology R & D Co ltd
Priority date: 2021-07-29
Filing date: 2021-07-29
Publication date: 2021-10-01

Abstract

The invention belongs to the technical field of Fischer-Tropsch synthesis, and discloses a fixed bed reactor for Fischer-Tropsch synthesis, which comprises a shell, wherein the shell comprises an upper end enclosure, a cylinder body and a lower end enclosure which are sequentially connected, the cylinder body comprises an outer shell and an inner shell which are arranged inside and outside, and a gas-liquid separation channel is formed between the outer shell and the inner shell; the interior of the shell is sequentially divided into a vapor-liquid separation chamber, a cooling water distribution chamber, a reaction chamber and a product separation chamber from top to bottom, and the reaction chamber is positioned in the inner shell; a plurality of heat exchange tubes are arranged in the reaction chamber, the inlet ends of the heat exchange tubes are communicated with the cooling water distribution chamber, and the outlet ends of the heat exchange tubes are communicated with the vapor-liquid separation chamber; the top of the vapor-liquid separation chamber is provided with a vapor outlet, the vapor-liquid separation chamber is provided with a cooling water outlet pipe, the cooling water distribution chamber is provided with a cooling water inlet pipe, the reaction chamber is provided with a raw material inlet pipe, the gas-liquid separation channel is provided with a gas-phase product outlet pipe, and the bottom of the product separation chamber is provided with a liquid-phase product outlet. The invention has the advantages of simple structure, convenient operation, high heat transfer efficiency of products and low energy consumption of the system.

Description

Fixed bed reactor for Fischer-Tropsch synthesis

Technical Field

The invention relates to the technical field of Fischer-Tropsch synthesis, in particular to a fixed bed reactor for Fischer-Tropsch synthesis.

Background

The Fischer-Tropsch synthesis technology is an important chemical process for converting coal into hydrocarbon liquid fuel through indirect liquefaction, and the Fischer-Tropsch synthesis technology is more and more favored because the oil product synthesized through indirect liquefaction of coal has the characteristics of cleanness, environmental protection, excellent combustion performance and the like and is a direct substitute of fossil liquid fuel.

The Fischer-Tropsch synthesis technology can be divided into high-temperature Fischer-Tropsch synthesis and low-temperature Fischer-Tropsch synthesis according to the difference of the operating temperature and the obtained target product. The reactor is the core equipment of the Fischer-Tropsch synthesis process device, and can be divided into a fixed bed reactor, a bubbling slurry bed reactor and a fixed or circulating fluidized bed reactor according to different structures and operation modes of the reactor applied to the Fischer-Tropsch synthesis technology. Among them, the fixed bed reactor is the most commonly used one of several reactor forms because of its characteristics such as convenient operation, small mechanical abrasion of the catalyst and long service life.

The Fischer-Tropsch synthesis process is a strongly exothermic reaction process, and particularly for a fixed bed reactor, the temperature control of a reactor bed layer is particularly important. In the prior art, a fixed bed reactor for Fischer-Tropsch synthesis generally adopts a gas chilling structure and a liquid chilling structure, a steam pocket and a liquid wax separator are required to be arranged outside the reactor, the structure is complex, the operation and the control are complicated, and the energy consumption of a product separation process is high.

Disclosure of Invention

The invention aims to provide a fixed bed reactor for Fischer-Tropsch synthesis, which has the advantages of simple structure, convenient operation, high product heat transfer efficiency and low system energy consumption.

The technical scheme provided by the invention is as follows:

a fixed bed reactor for fischer-tropsch synthesis comprising:

the shell comprises an upper end enclosure, a cylinder body and a lower end enclosure, the cylinder body comprises an outer shell and an inner shell which are arranged inside and outside, the upper end enclosure and the lower end enclosure are respectively arranged at two ends of the outer shell, and a gas-liquid separation channel is formed between the outer shell and the inner shell;

a first partition plate, a second partition plate and a third partition plate are sequentially arranged in the shell from top to bottom, a plurality of through holes are formed in the third partition plate, the first partition plate, the second partition plate and the third partition plate divide the interior of the shell into a vapor-liquid separation chamber, a cooling water distribution chamber, a reaction chamber and a product separation chamber from top to bottom, the inner shell is located between the second partition plate and the third partition plate, the reaction chamber is located in the inner shell, and the gas-liquid separation channel is communicated with the product separation chamber;

a plurality of heat exchange tubes are arranged in the reaction chamber, the inlet ends of the heat exchange tubes are communicated with the cooling water distribution chamber, and the outlet ends of the heat exchange tubes are communicated with the vapor-liquid separation chamber;

the top of the vapor-liquid separation chamber is provided with a vapor outlet, one side of the bottom of the vapor-liquid separation chamber is connected with a cooling water outlet pipe, one side of the top of the cooling water distribution chamber is connected with a cooling water inlet pipe, one side of the top of the reaction chamber is connected with a raw material inlet pipe, one side of the top of the gas-liquid separation channel is connected with a gas-phase product outlet pipe, and the bottom of the product separation chamber is provided with a liquid-phase product outlet.

In the scheme, the raw material gas enters the reaction chamber from the side surface of the fixed bed reactor to carry out the Fischer-Tropsch synthesis reaction, the reacted material enters the product separation chamber, the liquid wax product is removed from a liquid phase product outlet at the bottom of the product separation chamber, and the gas phase and a small amount of liquid carried by the gas phase upwards enter the gas-liquid separation channel and flow from bottom to top. The gas phase product is removed from the reactor through a side gas phase product outlet in the upper part of the fixed bed reactor. Circulating water for cooling the reaction chamber enters the heat exchange tube from the cooling water distribution chamber, steam and water after heat exchange enter the steam-liquid separation chamber, steam is removed from the top steam outlet, and cooling water is removed from the side cooling water outlet pipe for circulation.

Further preferably, the outlet end of the heat exchange pipe is located above the cooling water outlet pipe.

In this scheme, the exit end of heat exchange tube is located the top of cooling water outlet pipe to make the steam of following the discharge in the heat exchange tube discharge from the steam outlet, and can not discharge from the cooling water outlet pipe.

Further preferably, the heat exchange tube comprises a downcomer and an upcomer, the top end of the downcomer extends into the cooling water distribution chamber and is communicated with the cooling water distribution chamber, the bottom end of the downcomer is communicated with the bottom end of the upcomer, and the top end of the upcomer extends into the vapor-liquid separation chamber and is communicated with the vapor-liquid separation chamber.

Further preferably, the pipe diameter of the riser is greater than the pipe diameter of the downcomer.

In the scheme, the pipe diameter of the ascending pipe is larger than that of the descending pipe, so that the flow resistance of steam-water two-phase flow can be reduced, the flow velocity of cooling water in the pipe is improved, and the heat exchange effect is enhanced.

Further preferably, the ratio of the pipe diameter of the downcomer to the pipe diameter of the riser is 1:1 to 3.2.

Further preferably, the air conditioner further comprises an annular deflector arranged below the third partition plate.

In the scheme, the annular guide plate is arranged below the third partition plate, so that a reaction product firstly enters the product separation chamber to be subjected to gas-liquid separation, and then a gas phase enters the gas-liquid separation channel, and the reaction product is prevented from directly entering the gas-liquid separation channel and being discharged from the gas-liquid separation channel without being subjected to gas-liquid separation.

Further preferably, the gas-liquid separation device further comprises a plurality of baffle plates which are arranged in the gas-liquid separation channel at intervals along the height direction of the shell.

In this scheme, through setting up baffling baffle, can carry out the secondary to the liquid of smuggleing secretly in the gaseous phase and separate, improve the separation effect.

Further preferably, the diameter ratio of the inner shell to the outer shell is 1: 1.1-2.6;

the ratio of the diameter of the inner shell to the height of the inner shell is 1: 0.5-12.5;

the ratio of the diameter of the outer shell to the height of the outer shell is 1: 3.5-19.

Further preferably, the through holes are uniformly formed in the third partition plate, and the aperture ratio of the third partition plate is 25% to 75%.

Further preferably, a liquid level detection device and a pressure detection device are further arranged in the vapor-liquid separation chamber.

The invention has the technical effects that:

through double-deck casing and multilayer baffle setting, the fixed bed reactor inner space with a segmentation is cut apart into vapour-liquid separation room, cooling water distribution room, the reaction chamber, gas-liquid separation passageway and result separation room, carry out the initial gross separation to the result after the reaction when accomplishing the ft synthesis reaction in the reaction chamber, and carry out vapour-liquid separation to the cooling water, the outside of reactor need not to set up the separator of steam pocket and liquid wax, simple structure not only, the flexible operation is convenient, product separation efficiency is high, and play the effect of strengthening the heat transfer through a plurality of heat exchange tubes that set up in the reaction chamber, make moving of reactor efficient, the system energy consumption is low.

Drawings

The invention is described in further detail below with reference to the following figures and detailed description:

FIG. 1 is a schematic diagram of a fixed bed reactor for Fischer-Tropsch synthesis according to an embodiment of the present disclosure;

FIG. 2 is a schematic structural view of a heat exchange tube;

fig. 3 is a top view of the cartridge.

The reference numbers illustrate:

10. a housing; 11. an upper end enclosure; 12. a lower end enclosure; 13. an outer housing; 14. an inner housing; 21. a vapor-liquid separation chamber; 211. a steam outlet; 212. a cooling water outlet pipe; 22. a cooling water distribution chamber; 221. a cooling water inlet pipe; 23. a reaction chamber; 231. a raw material inlet pipe; 24. a product separation chamber; 241. a liquid phase product outlet; 25. a gas-liquid separation channel; 251. a gas phase product outlet pipe; 31. a first separator; 32. a second separator; 33. a third partition plate; 40. a heat exchange pipe; 401. an inlet end; 402. an outlet end; 41. a down pipe; 42. a riser pipe; 43. connecting pipe fittings; 50. an annular baffle; 60. a baffle plate.

Detailed Description

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

For the sake of simplicity, the drawings only schematically show the parts relevant to the present invention, and they do not represent the actual structure as a product. In addition, in order to make the drawings concise and understandable, components having the same structure or function in some of the drawings are only schematically illustrated or only labeled. In this document, "one" means not only "only one" but also a case of "more than one".

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

In this context, it is to be understood that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not intended to indicate or imply relative importance.

A specific embodiment of a fixed bed reactor for fischer-tropsch synthesis, as shown in fig. 1, comprises a housing 10, wherein the housing 10 comprises an upper head 11, a cylinder and a lower head 12, the upper head 11, the cylinder and the lower head 12 form a closed container, preferably, the upper head 11 and the lower head 12 are both elliptical, and the cylinder is cylindrical.

The barrel includes shell body 13 and interior casing 14 of inside and outside setting, and upper cover 11 and low head 12 set up respectively at the both ends of shell body 13, form gas-liquid separation passageway 25 between shell body 13 and the interior casing 14, and the inside reactor 23 that forms the Fischer-Tropsch reaction of interior casing 14. Preferably, the diameter ratio of the inner shell 14 to the outer shell 13 is 1: 1.1-2.6. The ratio of the diameter of the inner shell 14 to the height of the inner shell 14 is 1: 0.5-12.5; the ratio of the diameter of the outer shell 13 to the height of the outer shell 13 is 1: 3.5-19. Preferably, the ratio of the diameter of the inner shell 14 to the height of the inner shell 14 is 1: 2-9.5, and the ratio of the diameter of the outer shell 13 to the height of the outer shell 13 is 1: 5-12.

The shell 10 is internally provided with a first partition plate 31, a second partition plate 32 and a third partition plate 33 from top to bottom in sequence, the first partition plate 31 is positioned above the catalyst bed layer, and preferably, the first partition plate 31 is positioned 200-800 mm above the catalyst bed layer. The second partition 32 and the third partition 33 are welded to the outer casing 13, and the inner casing 14 is located between the second partition 32 and the third partition 33.

The first partition plate 31, the second partition plate 32 and the third partition plate 33 divide the container inside the casing 10 into the vapor-liquid separation chamber 21, the cooling water distribution chamber 22, the reaction chamber 23 and the product separation chamber 24 in this order from the top. A vapor-liquid separation chamber 21 is formed above the first partition plate 31 and at the top of the upper head 11 and serves as a space for collecting and separating the boiled water after heat exchange, and a cooling water distribution chamber 22 is formed between the first partition plate 31 and the second partition plate 32 and serves as a buffer space for cooling water. The reaction chamber 23 is formed inside the inner casing 14 between the second partition 32 and the third partition 33, and the product separating chamber 24 is formed below the third partition 33.

The cylinder body is arranged in an inner-outer double-layer shell structure, the space between the second partition plate 32 and the third partition plate 33 can be divided into two chambers which are arranged inside and outside through the inner shell 14, the outer chamber is a gas-liquid separation channel 25 which is used as a gas-liquid separation space of materials after reaction, and a flow channel and a space for further separating entrained liquid phase from gas-phase products after reaction are provided. The inner cavity is a reaction chamber 23 for Fischer-Tropsch synthesis, and the reaction chamber 23 is filled with a catalyst to form a catalyst bed layer. The catalyst bed can be provided with a plurality of temperature detection points.

The catalyst in the reaction chamber 23 can be solid granular cobalt-based and/or iron-based catalyst, the catalyst is spherical and/or cylindrical, the external dimension of the catalyst is phi 1.5-15 mm, and the optimized external dimension is phi (2.5-8) × (2.5-8) mm. The catalysts loaded in the reaction chamber 23 may be the same type of catalyst or may be a combination of different types of catalysts. The shape and size of the catalyst may be the same or different. The catalyst may be diluted with inert material or by other means.

A third partition 33 is provided to support the catalyst bed inside the inner shell 14, and a product separation chamber 24 is provided below the third partition 33. The third partition 33 is uniformly provided with a plurality of through holes so that the gas-liquid separation channel 25 communicates with the product separation chamber 24, and the reaction chamber 23 communicates with the product separation chamber 24. The mixed product (liquid wax, gas-phase product, and unreacted raw material gas) reacted in the reaction chamber 23 flows downward through the through-holes of the third partition plate 33 into the product separation chamber 24, and the gas phase enters the gas-liquid separation channel 25 from the through-holes of the third partition plate 33. To reduce the resistance, the aperture ratio of the third partition 33 should be 25% to 75%.

The reaction chamber 23 is also provided with a plurality of heat exchange tubes 40, the heat exchange tubes 40 are uniformly distributed in the catalyst bed layer, the inlet ends 401 of the heat exchange tubes 40 are communicated with the cooling water distribution chamber 22, and the outlet ends 402 are communicated with the vapor-liquid separation chamber 21. Cooling water is introduced into the heat exchange tube 40 to remove the heat of the Fischer-Tropsch synthesis reaction.

The top of the vapor-liquid separation chamber 21 is provided with a vapor outlet 211, a vapor-liquid mixture generated after cooling water in the heat exchange tube 40 exchanges heat enters the vapor-liquid separation chamber 21 for separation, vapor moves upwards out of the vapor outlet 211 at the top, and water flows downwards and forms a certain liquid level. A cooling water outlet pipe 212 is connected to one side of the bottom of the vapor-liquid separation chamber 21, and the cooling water in the vapor-liquid separation chamber 21 is discharged from the cooling water outlet pipe 212.

One side of the top of the cooling water distribution chamber 22 is connected with a cooling water inlet pipe 221, cooling water enters the cooling water distribution chamber 22 through the cooling water inlet pipe 221, and enters the heat exchange tubes 40 through inlet ends 401 of the heat exchange tubes 40 uniformly distributed on the second partition plate 32 to transfer heat after pressure and flow stabilization in the cooling water distribution chamber 22.

The cooling water inlet pipe 221 is connected with the cooling water outlet pipe 212 arranged on the vapor-liquid separation chamber 21 in a direct connection mode, and a control valve and/or a pressure boosting pump can be arranged for boosting so as to realize the recycling of the cooling water. One or more cooling water outlet pipes 212 and cooling water inlet pipes 221 may be provided as needed, and when a plurality of cooling water inlet pipes 221 are provided, the plurality of cooling water inlet pipes 221 are uniformly distributed in the radial direction of the outer shell 10, and the plurality of cooling water outlet pipes 212 are uniformly distributed in the radial direction of the outer shell 10, that is, the plurality of cooling water inlet pipes 221 are located at the same height of the outer shell 10, and the plurality of cooling water outlet pipes 212 are located at the same height of the outer shell 10. Preferably, a liquid level detection device, a vapor pressure detection device and a water replenishing line are further arranged in the vapor-liquid separation chamber 21 for monitoring and control.

One side of the top of the reaction chamber 23 is connected with a raw material inlet pipe 231, the raw material inlet pipe 231 penetrates through the outer shell 13 and is connected with the inner shell 14, and raw material gas is conveyed into the reaction chamber 23 through the raw material inlet pipe 231 to carry out Fischer-Tropsch synthesis reaction. Raw material intake pipe 231 passes through welded fastening with shell body 13 and interior casing 14, and according to the demand that tubular product was heated, raw material intake pipe 231 can set up the expansion joint between interior casing 14 and shell body 13.

A gas-phase product outlet pipe 251 is connected to one side of the top of the gas-liquid separation channel 25, and the gas-phase product outlet pipe 251 is disposed below the raw material inlet pipe 231 and welded to the outer shell 13. The raw material inlet pipe 231 and the gas-phase product outlet pipe 251 may be provided in one or more numbers, respectively, as needed, and when a plurality of them are provided, they should be provided on the same cross section of the fixed-bed reactor.

The bottom of the product separation chamber 24 is provided with a liquid phase product outlet 241. A liquid level detection device may also be disposed within the product separation chamber 24 for detecting the liquid level within the product separation chamber 24 for ease of monitoring and operational control.

When the fixed bed reactor works, raw material gas enters a catalyst bed layer in the reaction chamber 23 from the raw material inlet pipe 231 to carry out Fischer-Tropsch synthesis reaction, the reacted material enters the product separation chamber 24 at the lower part of the reaction chamber 23, liquid wax is removed from the liquid phase product outlet 241, a gas phase and a small amount of entrained liquid enter the gas-liquid separation channel 25 between the inner shell 14 and the outer shell 13 and flow from bottom to top, the gas phase product is removed from the fixed bed reactor from the gas phase product outlet pipe 251, a heavy hydrocarbon product is obtained by cooling and separating the outside of the fixed bed reactor, the gas phase can also obtain light hydrocarbon and water by entering the three-phase separator after being continuously cooled, the gas phase part is used as the raw material gas for recycling, and the part is discharged as tail gas.

Circulating cooling water for cooling the catalyst bed layer enters the cooling water distribution chamber 22 from the cooling water inlet pipe 221, the cooling water in the cooling water distribution chamber 22 enters the heat exchange pipe 40 from the inlet end 401 of the heat exchange pipe 40, the cooling water exchanges heat with the catalyst bed layer outside the heat exchange pipe 40 to remove reaction heat, the cooling water is partially evaporated to generate steam, a steam-water mixture after heat exchange enters the steam-liquid separation chamber 21 at the top of the fixed bed reactor from the outlet end 402 of the heat exchange pipe 40, the steam is removed from the steam outlet 211 at the top, and the cooling water is removed from the cooling water outlet pipe 212 at the side for circulating use.

According to the invention, through the arrangement of the double-layer shell and the multiple layers of partition plates, the internal space of the one-stage fixed bed reactor is divided into the vapor-liquid separation chamber 21, the cooling water distribution chamber 22, the reaction chamber 23, the product separation chamber 24 and the vapor-liquid separation channel 25, the product after the reaction is primarily separated while the Fischer-Tropsch synthesis reaction is completed in the reaction chamber 23, and the cooling water is subjected to vapor-liquid separation, a vapor drum and a liquid wax separator are not required to be arranged outside the reactor, so that the structure is simple, the operation is flexible and convenient, the product separation efficiency is high, and the heat transfer enhancement effect is achieved through the multiple heat exchange tubes 40 arranged in the reaction chamber 23, so that the heat transfer efficiency of the reactor is high, and the energy consumption of the system is low.

When the fixed bed reactor in the embodiment is applied to a Fischer-Tropsch synthesis reaction process system, the fixed bed reactor can be a single fixed bed reactor or a plurality of fixed bed reactors, and a plurality of fixed bed reactors can be connected in series or in parallel, or part of the fixed bed reactors is connected in series and part of the fixed bed reactors is connected in parallel. Or the fixed bed reactor of the embodiment is used in series and parallel with other reactors, for example, the fixed bed reactor can be combined with a slurry bed reactor and/or a fluidized bed reactor and/or be used in series, parallel and/or series and parallel connection.

The operating conditions for performing the fischer-tropsch synthesis reaction using the fixed bed reactor of this example were: the reaction pressure is 1.2-5.0 MPa, the reaction temperature is 180-430 ℃, and H in the raw material gas component₂The ratio of the carbon monoxide to the CO is 1.6-5.5: 1(mol ratio), and the feeding space velocity of the raw material gas is 200-3500 h^-1。

Preferably, as shown in fig. 2, the outlet end 402 of the heat exchange pipe 40 is located above the cooling water outlet pipe 212. Preferably, the outlet end 402 of the heat exchange pipe 40 may be disposed 500 to 1800mm above the first separator 31, and the cooling water outlet pipe 212 is disposed 200 to 800mm above the first separator 31.

As shown in fig. 2, the heat exchange tube 40 includes a downcomer 41 and an upcomer 42, the top end of the downcomer 41 extends into the cooling water distribution chamber 22 and communicates with the cooling water distribution chamber 22, the bottom end of the downcomer 41 communicates with the bottom end of the upcomer 42, and the top end of the upcomer 42 extends into the vapor-liquid separation chamber 21 and communicates with the vapor-liquid separation chamber 21. The top end of the downcomer 41 is the inlet end 401 of the heat exchange tube 40, and the top end of the upcomer 42 is the outlet end 402 of the heat exchange tube 40. The top end of the downcomer 41 is welded to the second partition plate 32, the riser 42 passes through the second partition plate 32 and the first partition plate 31, and is welded to the first partition plate 31 and the second partition plate 32, the downcomer 41 and the riser 42 are connected in series by a connecting pipe 43, cooling water enters from the top end of the downcomer 41, flows from top to bottom in the downcomer 41, enters the riser 42, flows from bottom to top in the riser 42, and enters the vapor-liquid separation chamber 21 from the top end of the riser 42.

In order to reduce the flow resistance, increase the flow rate of cooling water in the pipe and enhance heat exchange, the ascending pipe 42 is a row pipe with a slightly larger pipe diameter, and the ratio of the pipe diameters of the descending pipe 41 and the ascending pipe 42 is 1: 1-3.2. Catalyst is filled between the outside of the heat exchange tube 40 and the inner housing 14.

Preferably, as shown in fig. 1, an annular baffle 50 is further disposed below the third partition 33, an upper edge of the annular baffle 50 is welded to the third partition 33 for suspension support, and a support member can be welded to the outer shell 13 for auxiliary support of the annular baffle 50. The diameter ratio of the lower edge to the upper edge of the annular guide plate 50 is 1: 1-8. A plurality of baffle plates 60 are provided in the gas-liquid separation passage 25 at intervals in the height direction for secondarily separating the liquid entrained in the gas phase, and as shown in fig. 3, the baffle plates 60 are formed in a honeycomb shape in the gas-liquid separation passage 25 and are fixed by being welded to the inner shell 14 and the outer shell 13 through support members.

The mixed product after reaction in the catalyst bed (reaction chamber 23) enters the product separation chamber 24 at the lower part of the reaction chamber 23 through the annular guide plate 50 for gas-liquid separation, the liquid phase product enters the bottom of the product separation chamber 24, the gas phase product which is preliminarily separated and carried with a small amount of liquid flows upwards in a gas-liquid separation channel 25 between the inner shell 14 and the outer shell 13 in a baffling way, flows upwards from bottom to top, and after the liquid carried by the baffling baffle 60 is further separated, the gas phase product is removed from a gas phase product outlet pipe 251.

Preferably, an exhaust port is provided below the first partition plate 31, and the gas in the cooling water distribution chamber 22 is exhausted through the exhaust port. A drain outlet is arranged above the second partition plate 32, and water in the cooling water distribution chamber 22 can be drained when needed.

Example 1

The Fischer-Tropsch synthesis fixed bed reactor is phi 2.6 meters, an iron-based catalyst is filled in a bed layer (reaction chamber) of the reactor, and the catalyst is cylindrical with the external dimension phi 4 multiplied by 5 mm. The operating conditions of the fixed bed Fischer-Tropsch synthesis reactor are as follows: h in inlet feed gas₂The mol ratio of/CO is 1.8, and the air inlet space velocity is 2200h^-1The reaction temperature is 235 ℃, and the reaction pressure is 2.8 MPa. Three layers of transverse partition plates are arranged in the fixed bed reactor, an inner shell is arranged between the second layer of partition plate and the third layer of partition plate, the diameter ratio of the inner shell to the outer shell is 1:1.3, and the height-diameter ratio of a catalyst bed layer (reaction chamber) of the reactor is 6:1The height-diameter ratio of the fixed bed reactor is 8.5: 1. the fixed bed reactor is provided with 3 raw material air inlets which are uniformly distributed on the same horizontal plane. The gas phase product outlets are arranged 4 and are uniformly distributed on the same horizontal plane. The heat exchange tubes are 1084 groups, and the pipe diameter ratio of the ascending pipe to the descending pipe is 1: 1.25. The cooling water outlet pipes and the cooling water inlet pipes are 4, the booster pumps are arranged between the cooling water outlet pipes and the cooling water inlet pipes, and the steam-water separation chamber is provided with a cooling water supplementing water pipeline for controlling the liquid level of the steam-liquid separation chamber. The raw material gas enters a catalyst bed layer of an inner shell from the side surface of a fixed bed reactor through 3 uniformly distributed raw material inlet pipes to carry out Fischer-Tropsch synthesis reaction, the reacted material enters a product separation chamber at the lower part of the catalyst bed layer, liquid wax is removed from a liquid phase product outlet at the bottom of the reactor, a gas phase and a material carrying a small amount of liquid enter a gas-liquid separation channel between an inner shell and an outer shell of the reactor, flow from bottom to top, and the carried liquid is further separated when passing through a baffling baffle. And gas-phase products are removed from the reactor from the upper part of the fixed bed reactor through 4 gas-phase product outlets, heavy hydrocarbon products are obtained by cooling and separating the outside of the fixed bed reactor, the gas phase is continuously cooled and enters a three-phase separator to obtain light hydrocarbon and water, part of the gas phase is used as raw material gas for recycling, and part of the gas phase is discharged as tail gas. Circulating water for cooling a reactor bed layer enters a cooling water distribution chamber from 4 symmetrically arranged inlets at the upper part of the reactor bed layer, enters a heat exchange pipe after steady flow and pressure stabilization, cold water exchanges heat with a catalyst bed layer outside the pipe through a descending pipe and an ascending pipe to remove reaction heat, cooling water is partially evaporated to generate steam, a steam-water mixture after heat exchange enters a steam-water collecting and separating space at the upper part of the reactor, the steam is removed from the top, and the cooling water is removed from the side surface through 4 symmetrically arranged outlets and is circulated after being pressurized by a pump. The outside of the reactor is not provided with a steam drum and a separator of liquid wax. The reactor had a CO conversion per pass of 32.65% at operating conditions and C in the product₅₊The selectivity of (A) is 92.76%, and 1.5MPa steam is by-produced.

Example 2

The Fischer-Tropsch synthesis fixed bed reactor has a diameter of 3.2 m and a reactor bed layer (reaction chamber)) A cobalt-based catalyst was packed in the reactor, and the catalyst had a cylindrical shape with an outer dimension of phi 3.5X 4 mm. The operating conditions of the fixed bed Fischer-Tropsch synthesis reactor are as follows: h in inlet feed gas₂The mol ratio of/CO is 2.2, and the air inlet space velocity is 2500h^-1The reaction temperature is 215 ℃, and the reaction pressure is 3.0 MPa. 3 layers of transverse partition plates are arranged in the fixed bed reactor, an inner shell is arranged between the second layer of partition plate and the third layer of partition plate, the diameter ratio of the inner shell to the outer shell is 1:1.4, the height-diameter ratio of a catalyst bed layer of the reactor is 5.2:1, and the height-diameter ratio of the fixed bed reactor is 8: 1. the fixed bed reactor is provided with 4 raw material air inlets which are uniformly distributed on the same horizontal plane. The gas phase product outlets are arranged 4 and are uniformly distributed on the same horizontal plane. The heat exchange tubes are 1356 groups, and the pipe diameter ratio of the ascending pipe to the descending pipe is 1: 1.25. The cooling water outlet pipes and the cooling water inlet pipes are 6, the booster pumps are arranged between the cooling water outlet pipes and the cooling water inlet pipes, and the steam-water separation chamber is provided with a water supplementing pipeline for cooling water and used for controlling the liquid level of the steam-water separation chamber. The raw material gas enters a catalyst bed layer of an inner shell from the side surface of a fixed bed reactor through 4 gas inlet pipes which are uniformly distributed to carry out Fischer-Tropsch synthesis reaction, the reacted material enters a product separation chamber at the lower part of the catalyst bed layer, the liquid wax is removed from the bottom of the product separation chamber, the gas phase and the material flow carrying a small amount of liquid enter a gas-liquid separation channel between an inner shell and an outer shell of the reactor, flow from bottom to top, and the carried liquid is further separated when passing through a baffling baffle. And gas-phase products are removed out of the fixed bed reactor from 4 gas-phase product outlets at the upper part of the reactor, heavy hydrocarbon products are obtained by cooling and separating the outside of the fixed bed reactor, the gas phase is continuously cooled and then enters a three-phase separator to obtain light hydrocarbon and water, part of the gas phase is used as raw material gas for recycling, and part of the gas phase is discharged as tail gas. Circulating water for cooling a reactor bed layer enters a cooling water distribution chamber from the upper part of the reactor bed layer through 6 symmetrically arranged inlets, enters a heat exchange pipe after steady flow and pressure stabilization, cooling water exchanges heat with a catalyst bed layer outside the pipe through a descending pipe and an ascending pipe to remove reaction heat, cooling water is partially evaporated to generate steam, a steam-water mixture after heat exchange enters a steam-water collecting and separating space at the upper part of the reactor, the steam is removed from the top, and the cooling water passes through the side surface of the reactor bed layer and is used for cooling the reactor bed layerThe 6 outlets of the scale arrangement were removed and pumped up for circulation. The outside of the reactor is not provided with a steam drum and a separator of liquid wax. The reactor had a CO conversion per pass of 33.82% at operating conditions and C in the product₅₊The selectivity of (A) is 92.13%, and 1.3MPa steam is by-produced.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A fixed bed reactor for fischer-tropsch synthesis, comprising:

2. A fixed bed reactor for fischer-tropsch synthesis according to claim 1, wherein the outlet ends of the heat exchange tubes are located above the cooling water outlet tube.

3. A fixed bed reactor for fischer-tropsch synthesis according to claim 2, wherein said heat exchange tubes comprise a downcomer and a riser, the top end of said downcomer extending into and communicating with said cooling water distribution chamber, the bottom end of said downcomer communicating with the bottom end of said riser, the top end of said riser extending into and communicating with said vapor-liquid separation chamber.

4. A fixed bed reactor for fischer-tropsch synthesis according to claim 3, wherein the riser has a larger tube diameter than the downcomer.

5. A fixed bed reactor for Fischer-Tropsch synthesis according to claim 4, wherein the ratio of the tube diameter of the downcomer to the tube diameter of the riser is from 1:1 to 3.2.

6. A fixed bed reactor for use in Fischer-Tropsch synthesis according to any one of claims 1 to 5, further comprising an annular baffle disposed below the third partition.

7. A fixed bed reactor for use in Fischer-Tropsch synthesis according to any one of claims 1 to 5, further comprising a plurality of baffle plates disposed at intervals along the height of the housing within the gas-liquid separation channel.

8. A fixed bed reactor for Fischer-Tropsch synthesis according to any one of claims 1 to 5,

the diameter ratio of the inner shell to the outer shell is 1: 1.1-2.6;

9. A fixed bed reactor for use in Fischer-Tropsch synthesis according to any one of claims 1 to 5, wherein the through holes are uniformly arranged in the third partition wall, and the third partition wall has an open cell content of 25 to 75%.

10. A fixed bed reactor for Fischer-Tropsch synthesis according to any one of claims 1 to 5, characterised in that a liquid level detection means and a pressure detection means are also provided in the vapour-liquid separation chamber.