Apparatus and method for continuous activation of catalyst and fischer-tropsch synthesis reactor and method comprising the same

Abstract

The present application relates to the technical field of catalyst activation, and discloses a device and method for continuously activating a catalyst, and a Fischer-Tropsch synthesis reaction device and method comprising the device. The device comprises at least one catalyst storage tank, a gas-solid reactor and a purifier. The gas-solid reactor is internally provided with at least one partition plate, and the partition plate is provided with an overflow port and / or a communication port. The gas-solid reactor is provided with at least two groups of air injection members, and each processing space corresponds to one group of air injection members. The air injection members are used for injecting hydrogen and / or CO into the corresponding processing space to adjust the hydrogen-carbon volume ratio of the activation gas in the corresponding processing space. The purifier is used for purifying the activated gas to obtain purified circulating gas. The device can complete Fischer-Tropsch catalyst activation with high quality, minimize the activation time, realize continuous activation of the Fischer-Tropsch catalyst, simplify the process control difficulty, and greatly improve the production efficiency.

Description

Technical Field

[0001] This invention relates to the field of catalyst activation technology, specifically to equipment and methods for continuous catalyst activation, as well as Fischer-Tropsch synthesis apparatus and methods incorporating such equipment. Background Technology

[0002] Coal indirect liquefaction technology, due to its relatively mild reaction process and high added value, is one of the important ways to solve the shortage of liquid fuels and the clean utilization of coal. Fischer-Tropsch synthesis refers to the process of synthesizing hydrocarbon liquid fuels from syngas (H2+CO) produced from coal or natural gas in the presence of metal catalysts such as iron, cobalt, and ruthenium. Using a slurry bed reactor for Fischer-Tropsch synthesis offers many advantages, including uniform mixing of the gas, liquid, and solid phases, low pressure drop, good heat transfer, easy control of reaction temperature, and online catalyst renewal, making it a hot topic of research and development.

[0003] Fischer-Tropsch synthesis catalysts must be reduced or activated before use to obtain a stable active phase for the Fischer-Tropsch synthesis reaction. The activity and selectivity of the catalyst will change with the formation and content of iron oxide and iron carbides during the pretreatment activation process.

[0004] The activation of iron-based catalysts in the Fischer-Tropsch synthesis is mainly influenced by parameters such as activation temperature, pressure, activation gas composition, time, and gas-to-catalyst ratio. Different pretreatment activation conditions result in significant differences in the phase composition of the iron-based catalyst and its performance in the Fischer-Tropsch synthesis reaction. Pretreatment activation conditions have a significant impact on the catalyst's activity, selectivity, stability, and abrasion resistance. Even the most promising catalyst will not achieve high activity if poorly activated, and may even lead to the termination of the reaction. Iron-based catalysts have strict requirements for activation treatment; therefore, selecting appropriate pretreatment activation conditions is a prerequisite for ensuring ideal industrial operation results in the Fischer-Tropsch synthesis.

[0005] CN103934044B discloses a method for activating Fischer-Tropsch iron-based catalysts using slurry bed technology. The method primarily involves activating the catalyst under slurry conditions. When the feed gas conversion rate and oil yield of the Fischer-Tropsch synthesis reaction do not meet the process conditions, a portion of the spent catalyst is first discharged, and then the activated catalyst is transferred to the Fischer-Tropsch slurry bed reactor. This process is an intermittent replacement process. Furthermore, the low gas-liquid mass transfer efficiency leads to a long catalyst activation time. Because the activated catalyst is in slurry form, the slurry cannot be statically stored, ultimately resulting in a long catalyst activation cycle, long start-up time, and frequent catalyst replacement. The frequent intermittent replacement process increases the operational burden and is detrimental to the stable operation of the system.

[0006] CN105709858A discloses an apparatus and method for continuous reduction of a catalyst, which achieves continuous reduction of the catalyst by mixing in a rotary reactor. However, this apparatus can only operate at a fixed activation temperature and hydrogen-to-carbon ratio, and cannot activate the catalyst under optimal process conditions. Summary of the Invention

[0007] The purpose of this invention is to overcome the problem that existing technologies cannot achieve continuous production under optimized process conditions, and to provide equipment and methods for continuous catalyst activation, as well as Fischer-Tropsch synthesis reactors and methods incorporating such equipment. This equipment can activate catalysts under optimized process conditions, improve catalyst activity, and, in conjunction with a continuous catalyst replacement process, greatly enhance the operational stability of the Fischer-Tropsch synthesis reactor and achieve continuous production.

[0008] To achieve the above objectives, the present invention provides an apparatus for continuously activating a catalyst, the apparatus comprising:

[0009] At least one catalyst storage tank for storing fresh catalyst;

[0010] A gas-solid reactor, connected to the catalyst storage tank, is used to receive the fresh catalyst and activation feed gas, and to activate the fresh catalyst to obtain an activated catalyst. The gas-solid reactor has at least one baffle plate inside, dividing its internal space into at least two interconnected processing spaces. The baffle plate has an overflow port and / or a connecting port, allowing catalyst material entering the gas-solid reactor to flow from the previous processing space to the next. The gas-solid reactor is equipped with at least two sets of jetting elements, one set corresponding to each processing space. These jetting elements inject hydrogen and / or CO into the corresponding processing space to adjust the hydrogen-to-carbon volume ratio of the activation gas within that space.

[0011] A purifier, connected to the gas-solid reactor, is used to receive the activated gas discharged from the gas-solid reactor and purify the activated gas to obtain purified circulating gas.

[0012] A second aspect of the present invention provides a method for continuously activating a catalyst, the method comprising:

[0013] The catalyst is continuously fed and subjected to segmented activation treatment to obtain activated catalyst and activated gas. The activated gas is then purified to obtain purified circulating gas. The segmented activation treatment process includes multiple activation treatments. During each activation treatment, activation gas is injected into the tower to control the hydrogen-carbon volume ratio of the activation gas in each activation treatment and to control the activation temperature of each activation treatment accordingly.

[0014] A third aspect of the present invention provides a Fischer-Tropsch synthesis apparatus, the apparatus comprising: at least one Fischer-Tropsch slurry bed reactor and a device for continuously activating a catalyst as described in any one of the preceding claims, the Fischer-Tropsch slurry bed reactor having an activation catalyst inlet for receiving the activation catalyst.

[0015] A fourth aspect of the present invention provides a method for Fischer-Tropsch synthesis, the method comprising:

[0016] The Fischer-Tropsch inlet gas is continuously contacted with the activated catalyst prepared by any of the methods described above in a Fischer-Tropsch slurry bed reactor to carry out the Fischer-Tropsch synthesis reaction. After gas-liquid separation, hydrocarbon products are obtained.

[0017] Through the above technical solution, the continuous activation catalyst equipment of the present invention includes at least two interconnected processing spaces and at least two sets of jetting components, which can carry out multi-stage activation processing in the same gas-solid reactor, and independently control the hydrogen-carbon ratio of each stage of activation processing, so that the catalyst can achieve continuous activation process under optimized process conditions.

[0018] Furthermore, by setting at least two sets of heating and insulation components, the temperature of the hydrogen-to-carbon ratio in each section is controllable. This allows for continuous catalyst activation under controllable process parameters. Combined with a continuous catalyst replacement process, this achieves fully continuous operation of both catalyst activation and replacement. Simultaneously, the equipment of this invention has no rotating parts and can operate under high pressure.

[0019] The Fischer-Tropsch synthesis method proposed in this invention can directly transfer activated catalyst particles into a Fischer-Tropsch slurry bed reactor through continuous catalyst activation and continuous catalyst replacement. Due to the small instantaneous flow rate of the catalyst, the activated catalyst does not need to be pre-mixed uniformly with the slurry. After entering the Fischer-Tropsch slurry bed reactor (ideally a fully mixed flow reactor), the catalyst can be quickly and uniformly mixed, and the phenomenon of local temperature run-off in the Fischer-Tropsch slurry bed reactor can be avoided. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a device for continuously activating a catalyst according to one embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of a gas-solid reactor according to one embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of a gas-solid reactor according to another embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of a gas-solid reactor according to another embodiment of the present invention;

[0024] Figure 5This is a schematic diagram of the internal partition of a gas-solid reactor according to one embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of the internal partition of a gas-solid reactor according to another embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of the structure of a Fischer-Tropsch synthesis reactor according to one embodiment of the present invention;

[0027] Figure 8 This is a graph showing the relationship between the catalyst replacement amount and the operating time in Example 2 of the present invention.

[0028] Explanation of reference numerals in the attached figures

[0029] 1. First catalyst storage tank; 2. Second catalyst storage tank; 3. Gas-solid reactor

[0030] 4 Purifier 31 Gas-solid reactor body 311 Catalyst inlet

[0031] 312 Activated material outlet; 313 Baffle; 314 Overflow port

[0032] 315 Connecting Port, 316 Resistor, 32 Jet Assembly

[0033] 321 First group of jet components; 322 Second group of jet components; 32n Nth group of jet components

[0034] 5. Buffer tanks; 6. Fischer-Tropsch slurry bed reactor Detailed Implementation

[0035] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0036] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "at least one" means one, two, or more than two. "At least two sets" means two or more sets.

[0037] like Figures 1-6 As shown, the present invention provides a device for continuously activating a catalyst, which includes: at least one catalyst storage tank 1, 2, a gas-solid reactor 3, and a purifier 4.

[0038] The catalyst storage tanks 1 and 2 are used for storing fresh catalyst.

[0039] The gas-solid reactor 3 is connected to the catalyst storage tank 1 or 2, and is used to receive the fresh catalyst and the activation feed gas, and to activate the fresh catalyst to obtain an activated catalyst. The gas-solid reactor 3 has at least one partition 313 inside, which divides the internal space of the gas-solid reactor 3 into at least two interconnected processing spaces. The partition 313 is provided with an overflow port 314 and / or a connecting port 315, allowing the catalyst material entering the gas-solid reactor 3 to flow from the previous processing space to the next processing space. The gas-solid reactor 3 is provided with at least two sets of jetting elements, one set corresponding to each processing space. The jetting elements are used to inject hydrogen and / or CO into the corresponding processing space to adjust the hydrogen-to-carbon volume ratio of the activation gas in the corresponding processing space.

[0040] The purifier 4 is connected to the gas-solid reactor 3 and is used to receive the activated gas discharged from the gas-solid reactor 3 and purify the activated gas to obtain purified circulating gas.

[0041] According to a preferred embodiment of the present invention, the device for continuously activating the catalyst includes two catalyst storage tanks, namely a first catalyst storage tank 1 and a second catalyst storage tank 2, which are connected in parallel. In use, the gas-solid reactor 3 is alternately connected to the first catalyst storage tank 1 and the second catalyst storage tank 2 to achieve continuous feeding of fresh catalyst into the gas-solid reactor 3.

[0042] According to a preferred embodiment of the present invention, the gas-solid reactor 3 includes a gas-solid reactor body 31 and an air jet assembly 32, wherein the gas-solid reactor body 31 is provided with at least two interconnected processing spaces, and the air jet assembly 32 includes at least two sets of air jets, namely a first set of air jets 321, a second set of air jets 322, ..., an nth set of air jets 32n.

[0043] In some implementations, such as Figure 1 As shown, the gas-solid reactor 3 includes n processing spaces, namely A1, A2, ..., A n Each processing space corresponds to a set of jet components, and the corresponding jet assembly 32 includes jet components 321, 322, ..., 32n, where jet component 321 corresponds to processing space A1, jet component 322 corresponds to processing space A3, and so on, with jet component 32n corresponding to processing space A1. n .

[0044] Furthermore, the baffles 313 are vertically arranged within the gas-solid reactor body 31, and the number of baffles 313 is n-1, dividing the gas-solid reactor into n equal processing spaces, where n≥2. The processing spaces are set according to the activation requirements, with the minimum processing space required to meet the optimal activation process. Preferably, the number of baffles 313 is 4, and the gas-solid reactor is divided into 5 equal processing spaces.

[0045] According to a preferred embodiment of the present invention, the overflow port 314 is located on the upper part of the partition 313, and the overflow port 314 is circular or polygonal. In the present invention, the shape of the overflow port includes, but is not limited to: circle, square, rectangle, regular pentagon, regular hexagon, regular octagon, etc. Figure 5 The overflow port 314 shown is circular; the connecting port 315 is located at the lower part of the partition 313, and the connecting port 315 is circular or polygonal; in this invention, the shape of the connecting port includes, but is not limited to: circle, square, rectangle, regular pentagon, regular hexagon, regular octagon, etc., such as Figure 6The connecting port 315 shown is square. In actual use, the shape of the overflow port can be selected according to actual needs, and the size of the overflow port can also be selected according to actual needs. In principle, in the same gas-solid reactor, if the residence time of the catalyst is short, a larger overflow port should be selected, and if the residence time of the catalyst is long, a smaller overflow port should be selected.

[0046] An openable and closable barrier 316 is provided at the overflow port 314. The barrier 316 can cover the overflow port 314 and can only be opened in the direction of material flow, so that the material can pass through the overflow port 314 in one direction to prevent the catalyst from flowing back.

[0047] A gas delivery pipe is provided at the connection port 315 to facilitate the transfer of catalyst material from the previous processing space to the next processing space, making the catalyst easier to transfer; the gas delivery pipe is connected to the jetting component corresponding to the previous processing space.

[0048] Preferably, the overflow port 314 and the connecting port 315 of the partition 313 are staggered. For example... Figure 2 and Figure 4 In the structure shown, the overflow port 314 and the connecting port 315 are arranged alternately.

[0049] According to a preferred embodiment of the present invention, a catalyst inlet is provided on the lower side or top of the gas-solid reactor; such as Figure 2 and Figure 3 As shown, the catalyst inlet 311 is located on the lower side of the gas-solid reactor body 31, as... Figure 4 As shown, the catalyst inlet 311 is located at the top of the gas-solid reactor body 31.

[0050] In this invention, the catalyst inlet 311 and the overflow outlet 314 follow a staggered vertical arrangement: if the catalyst inlet is on the lower side, an overflow outlet is provided on the adjacent first partition plate; if the catalyst inlet is on the top, a communication outlet is provided on the upper part of the adjacent first partition plate.

[0051] The first scenario: If the catalyst inlet is located below the side of the gas-solid reactor, an overflow port is provided on the baffle plate adjacent to the catalyst inlet; overflow ports are provided on all other baffle plates, or overflow ports and connecting ports are arranged alternately; for example... Figure 2 and Figure 3 As shown, the catalyst inlet 311 is located on the lower side of the gas-solid reactor body 31, and an overflow port 314 is provided on the partition plate 313 adjacent to the catalyst inlet 311.

[0052] In some implementations, such as Figure 2As shown, overflow ports 314 and connecting ports 315 are staggered on the partition 313. That is, the first partition has an overflow port 314, the second partition has a connecting port 315, the third partition has an overflow port 314, the fourth partition has a connecting port 315, and so on, forming n processing spaces, namely A1, A2, ..., A n With this structure, the catalyst can remain in the reactor for a sufficient period of time, thereby ensuring the quality of catalyst activation.

[0053] In other implementations, such as Figure 3 As shown, each of the partitions 313 is provided with an overflow port 314, forming n processing spaces, namely B1, B2, ..., B n .

[0054] The second scenario: If the catalyst inlet is located at the top of the gas-solid reactor, a connecting port is provided on the partition plate adjacent to the catalyst inlet, and the overflow port and the connecting port on the partition plate are staggered.

[0055] In some implementations, such as Figure 4 As shown, the catalyst inlet 311 is located at the top of the gas-solid reactor body 31, and a connecting port 315 is provided on the partition plate 313 adjacent to the catalyst inlet 311. The overflow port 314 and the connecting port 315 on the partition plate 313 are arranged alternately, that is, the first partition plate has a connecting port 315, the second partition plate has an overflow port 314, the third partition plate has a connecting port 315, the fourth partition plate has an overflow port 314, and so on, forming n processing spaces, namely C1, C2, ..., C n .

[0056] According to the present invention, such as Figure 1 As shown, a gas outlet is also provided at the top of the gas-solid reactor body 31. Each processing space corresponds to a gas outlet. All gas outlets of all spaces are connected in series with gas pipelines. The activated gas of each processing space is discharged from the corresponding gas outlet. After being collected in the gas pipeline, it enters the purifier 4. The purifier 4 purifies the activated gas into purified circulating gas, which is then used for the activation treatment of fresh catalyst.

[0057] According to a preferred embodiment of the present invention, the gas-solid reactor is further provided with at least two sets of heating and heat preservation components, preferably heat exchange tubes, with each processing space corresponding to one set of heating and heat preservation components, used to control the temperature of the catalyst in the corresponding processing space.

[0058] According to a preferred embodiment of the present invention, the gas-solid reactor is provided with 5 interconnected processing spaces, 5 sets of jetting elements and 5 sets of heating and insulation components; each set of heating and insulation components includes a heating part and an insulation part, wherein the heating part is a steam heat exchange jacket and the insulation part is composed of multiple layers of insulation material; preferably, each set of jetting elements includes 3-5 nozzles.

[0059] Preferably, each jet assembly includes at least one gas distributor, and each gas distributor includes a gas distribution main pipe, gas distribution branch pipes, and nozzles. Preferably, the gas distributor is located in the lower region of the processing space.

[0060] Furthermore, the nozzle extends through the heating and insulation assembly into the gas-solid reactor.

[0061] In this invention, the activation feed gas is the gas injected into the gas-solid reactor from the jetting element. Each processing space corresponds to a set of jetting elements, and each set of jetting elements corresponds to a set of activation feed gas. Each set of activation feed gas is injected into the gas-solid reactor independently. The activation feed gas includes fresh activation gas and purified circulating gas. Fresh activation gas refers to unused raw materials containing reducing gases, such as hydrogen and CO. Purified circulating gas refers to the gas obtained after the activated gas has undergone a series of treatments. The activated gas refers to the gas obtained after the activation feed gas has undergone an activation-reduction reaction with the catalyst and has been purified by a purifier. The activation gas after contacting the catalyst material is called the activation gas. The activation gas refers to the gas that participates in the activation process. The hydrogen-to-carbon ratio in the activation gas changes dynamically as the activation reaction proceeds. In this invention, the activation gas in each processing space is relatively independent.

[0062] In this invention, the hydrogen-to-carbon ratio of the activated gas entering the tower can be adjusted according to design requirements; an online chromatograph can be used to monitor the hydrogen-to-carbon ratio at each control point.

[0063] The present invention also provides a method for continuously activating a catalyst, comprising the following steps:

[0064] (1) The catalyst is continuously fed and the catalyst is subjected to segmented activation treatment to obtain activated catalyst and activated gas; the segmented activation treatment process includes multiple activation treatments. During each activation treatment, activation gas is injected into the tower to control the hydrogen-carbon volume ratio of the activation gas in each activation treatment and the activation temperature of each activation treatment is controlled accordingly.

[0065] (2) The activated gas is purified to obtain purified circulating gas;

[0066] In this invention, "hydrogen-carbon volume ratio" refers to the volume ratio of hydrogen to carbon monoxide.

[0067] This invention improves the activity of the catalyst and the selectivity of heavy hydrocarbons, and reduces the selectivity of carbon dioxide and methane by controlling the hydrogen-to-carbon volume ratio of the activated gas entering the tower in stages and the residence time of the catalyst.

[0068] In some preferred embodiments, the hydrogen-to-carbon volume ratio of the activated gas entering the tower is 3-20:1, preferably 3-10:1, and the inlet linear velocity of the activated gas entering the tower is 0.1-0.8 m / s, preferably 0.2-0.5 m / s.

[0069] According to a preferred embodiment of the present invention, along the feed direction of the catalyst, the hydrogen-to-carbon volume ratio gradient of the activated gas in each activation treatment stage decreases, and the decreasing gradient of the hydrogen-to-carbon volume ratio between two adjacent activation treatment stages is 2-5:1.

[0070] In this invention, the activated gas entering the tower includes activated fresh gas and purified circulating gas, and the volume ratio of activated fresh gas to purified circulating gas is 2-5:1, preferably 2-3:1; the fresh activated gas is at least one of hydrogen and CO, preferably the activated gas entering the tower is a mixture of hydrogen and CO, and the CO content of the purified circulating gas is not less than 1.2-1.5%.

[0071] In some embodiments, the hydrogen-to-carbon volume ratio gradient of the activated fresh gas decreases in each stage of the activation process along the feed and discharge direction of the catalyst.

[0072] Preferably, the hydrogen-to-carbon volume ratio of the activated fresh gas is 10:1 to 1:1, and the decreasing gradient of the hydrogen-to-carbon volume ratio between adjacent activation stages is 2-5:1; for example, the hydrogen-to-carbon volume ratio of the activated fresh gas is controlled in n stages, and along the feed direction of the catalyst, the hydrogen-to-carbon volume ratios of each stage are: X1, X2, ..., X... n-1 X n Where n≥2, X n The value range is 10:1-1:1, X n-1 With X n The ratio of the two values ​​ranges from 2 to 5:1. This can further improve the catalyst activity and selectivity for heavy hydrocarbons, while reducing the selectivity for carbon dioxide and methane.

[0073] According to a preferred embodiment of the present invention, the method includes: performing a five-stage activation treatment on the catalyst, wherein the hydrogen-carbon volume ratios of the activation gas entering the tower in the five stages of activation treatment are 50-20:1, 20-10:1, 10-6:1, 6-4:1, and 4-2:1, preferably 30:1, 15:1, 8:1, 5:1, and 3:1, along with the catalyst feed direction.

[0074] In this invention, the activation temperature of the segmented activation treatment is 130-300℃, preferably 150-280℃, and the activation pressure is 1-5MPa, preferably 2-3MPa.

[0075] In some embodiments, the activation temperature gradient increases along the catalyst feed direction for each activation stage, with the first temperature being 150-180°C and the temperature increase gradient between adjacent activation stages being 15-30°C. For example, when controlling the hydrogen-to-carbon ratio of the activation gas in n stages, there are also corresponding n-point temperature controls, with the temperatures corresponding to the hydrogen-to-carbon ratio of each stage along the flow direction being: T1, T2, ..., T... n-1 T n Where n≥2; T n The value range is 150-260℃.

[0076] According to a preferred embodiment of the present invention, the method includes: performing a five-stage activation treatment on the catalyst, wherein the activation temperatures of the five-stage activation treatment are 145-175℃, 175-205℃, 205-235℃, 235-265℃ and 265-295℃, preferably 170℃, 200℃, 230℃, 250℃ and 270℃.

[0077] In this invention, temperature is controlled in stages by gradient heating, and the temperature control method of gradient heating followed by heat preservation ensures that the activation reaction of the catalyst proceeds smoothly. This can prevent the reaction from being too violent and affecting the strength of the catalyst, and also prevent the generation of large amounts of water and carbon dioxide.

[0078] By controlling the hydrogen-to-carbon ratio of the activation gas in stages and controlling the activation temperature, different hydrogen-to-carbon ratios correspond to different activation temperatures, which can further improve the catalyst activity and selectivity for heavy hydrocarbons, and reduce the selectivity for carbon dioxide and methane.

[0079] In some embodiments, the residence time of the catalyst in each activation treatment is 0.5-2 hours.

[0080] According to a preferred embodiment of the present invention, the method includes: performing a 5-stage activation treatment on the catalyst, wherein the residence time of each stage of activation treatment is the same, which is 0.5-2h, preferably 1-1.5h.

[0081] In this invention, the continuous feeding includes the following steps:

[0082] The fresh catalyst was divided into two parts, and gas replacement and heating / pressurization operations were carried out separately for each part.

[0083] The two portions of fresh catalyst are fed alternately.

[0084] In some embodiments, the continuous feeding includes: Figure 1 As shown, fresh catalyst is added to the first catalyst storage tank 1 and the second catalyst storage tank 2 respectively for gas replacement and heating / pressurization operations; then the fresh catalyst in the first catalyst storage tank 1 and the fresh catalyst in the second catalyst storage tank 2 are alternately added to the gas-solid reactor 3.

[0085] Specifically, the continuous feeding includes: adding fresh catalyst to the first catalyst storage tank 1, performing gas purging and heating / pressurization operations on the first catalyst storage tank 1; simultaneously, adding fresh catalyst to the second catalyst storage tank 2, performing gas purging and heating / pressurization operations on the second catalyst storage tank 2; continuously adding the fresh catalyst from the first catalyst storage tank 1 to the gas-solid reactor 3; when the amount of fresh catalyst in the first catalyst storage tank 1 is lower than the design value, preferably lower than 5-20% of the total dosage, rapidly switching to the second catalyst storage tank 2, and... The fresh catalyst in the second catalyst storage tank 2 is continuously added to the gas-solid reactor 3. At the same time, the fresh catalyst is added to the first catalyst storage tank 1, and the first catalyst storage tank 1 is subjected to gas replacement and heating / pressurization. When the amount of fresh catalyst in the second catalyst storage tank 2 is lower than the design value, preferably lower than 5-20% of the total dosage, the system is quickly switched to the first catalyst storage tank 1. This process is repeated, and the fresh catalyst is continuously fed into the gas-solid reactor 3 by alternating feeding of the first catalyst storage tank 1 and the second catalyst storage tank 2.

[0086] In an embodiment of the present invention, the gas replacement includes: first replacing the gas with N2 multiple times, preferably 2 to 3 times, to ensure that there is no O2 in the feeding tank, and then replacing the gas with H2 or synthesis gas multiple times, preferably 2 to 3 times.

[0087] In this embodiment of the invention, the heating and pressurization operation includes: controlling the pressure at 1.0–5.0 MPa and the temperature at 80–150°C. All pressures mentioned in this invention are gauge pressures.

[0088] In a preferred embodiment of the present invention, the purification process includes: sequentially subjecting the activated gas to condensation and cooling, gas-liquid separation, CO2 removal, pressurization, and dehydration; wherein the volume fraction of CO2 in the purified circulating gas is less than 2%, preferably 0.2-1%; and the water content is less than 100 ppm by mass, preferably 20-50 ppm by mass. This can improve the utilization efficiency and reduction-activation effect of the purified circulating gas.

[0089] The present invention has no special requirements on the composition of the catalyst, and preferably uses iron-based catalysts commonly used in the field for Fischer-Tropsch synthesis; the present invention has no special requirements on the morphology of the catalyst, which can be spherical, granular or strip-shaped, etc.

[0090] According to a preferred embodiment of the present invention, the catalyst is a microspherical Fischer-Tropsch synthesis iron-based catalyst particle with an average particle size of 40-150 μm, preferably 60-100 μm.

[0091] In this invention, the method for continuously activating the catalyst can be carried out in the aforementioned equipment for continuously activating the catalyst, wherein the catalyst flows through each processing space and undergoes activation treatment in each stage.

[0092] like Figure 1 As shown, fresh catalyst enters from the catalyst inlet 311 of the gas-solid reactor 3 and then exits from the activated material outlet 312. The size of the gas-solid reactor 3 can be selected according to the activation scale of the catalyst particles. It is particularly important to note that during the activation reaction, the hydrogen-carbon ratio and temperature of each activation stage can be adjusted as needed to improve the activity or selectivity of the catalyst. At the same time, it is necessary to reduce the wear of the catalyst particles while ensuring that the catalyst and the activation gas achieve reduction activation in contact.

[0093] The embodiments of the present invention achieve continuous activation under optimal process conditions by controlling the reaction temperature and hydrogen-carbon ratio of each stage, thereby achieving precise control of the activation reaction process. The above control process enables the catalyst to be activated under a better process, resulting in a catalyst with high activity after activation.

[0094] like Figure 7 As shown, the present invention also provides a Fischer-Tropsch synthesis apparatus, comprising: at least one Fischer-Tropsch slurry bed reactor 6 and the aforementioned device for continuously activating a catalyst, wherein the Fischer-Tropsch slurry bed reactor 6 has an activation catalyst inlet for receiving the activation catalyst separated from the purifier 4.

[0095] Furthermore, a buffer tank 5 is provided between the Fischer-Tropsch slurry bed reactor 6 and the device for continuously activating the catalyst. The buffer tank 5 is used to receive the activated catalyst separated from the purifier 4 and then send it into the Fischer-Tropsch slurry bed reactor 6.

[0096] When starting up or when abnormal conditions occur in the Fischer-Tropsch slurry bed reactor, the activated catalyst can be stored in a buffer tank.

[0097] In some preferred embodiments, the Fischer-Tropsch synthesis apparatus includes two Fischer-Tropsch slurry bed reactors, which are connected to a device for continuous catalyst activation, i.e., the device for continuous catalyst activation continuously supplies activation catalyst to the two Fischer-Tropsch slurry bed reactors.

[0098] In this invention, the Fischer-Tropsch slurry bed reactor has a first discharge port, a second discharge port, and a third discharge port, which are located at the upper, middle, and lower parts of the Fischer-Tropsch slurry bed reactor, respectively. Preferably, the waste catalyst slurry is discharged from the first discharge port and the second discharge port.

[0099] The spent catalyst in the Fischer-Tropsch slurry bed reactor is continuously discharged from the catalyst discharge port set on the reactor, maintaining a stable catalyst stock in the reactor.

[0100] The present invention also provides a method for Fischer-Tropsch synthesis, the method comprising:

[0101] The Fischer-Tropsch inlet gas is continuously contacted with the activated catalyst prepared by the aforementioned method in a Fischer-Tropsch slurry bed reactor to carry out the Fischer-Tropsch synthesis reaction. After gas-liquid separation, hydrocarbon products are obtained.

[0102] Preferably, the temperature of the Fischer-Tropsch synthesis reaction is 100–300°C, more preferably 200–260°C, and the pressure is 0.5–4 MPa, more preferably 2–3 MPa.

[0103] In this invention, such as Figure 1 As shown, the Fischer-Tropsch feed gas includes fresh synthesis gas and Fischer-Tropsch recycle gas. Fresh synthesis gas is a mixture of hydrogen and CO. Fischer-Tropsch recycle gas refers to the gas obtained after the Fischer-Tropsch feed gas has undergone a series of treatments after contacting the activated catalyst to carry out the Fischer-Tropsch synthesis reaction.

[0104] Preferably, the Fischer-Tropsch feed gas comprises fresh synthesis gas and Fischer-Tropsch cycle gas, wherein the volume hourly space velocity (VHSV) of the fresh synthesis gas is 4000-6000 h⁻¹. -1 The volume ratio of the fresh synthesis gas to the Fischer-Tropsch cycle gas is 2-5:1, preferably 2-3:1; the volume ratio of hydrogen to CO in the Fischer-Tropsch inlet gas is 2-5:1, preferably 3-4:1; the volume ratio of hydrogen to CO in the fresh synthesis is 1.3-2.5:1, preferably 1.5-1.8:1.

[0105] Specifically, the activated catalyst in the gas-solid reactor is continuously transferred to the Fischer-Tropsch slurry bed reactor.

[0106] Preferably, when continuously activating fresh catalyst, for a single-series Fischer-Tropsch synthesis reactor with a capacity of 500,000 t / a, the dense-phase transport flow rate of the catalyst is 50-200 kg / h.

[0107] The present invention will be described in detail below through examples. The catalyst used in the following examples is CNFT-1, an iron-based catalyst for Fischer-Tropsch synthesis developed by the Beijing Low Carbon Clean Energy Research Institute of the State Energy Group.

[0108] Example 1

[0109] Adopting such Figure 1 The apparatus shown is for continuous catalyst activation, wherein the gas-solid reactor 3 comprises five interconnected processing spaces, each with dimensions of 2cm × 2cm × 5cm. He is used to simulate H2, and N2 is used to simulate CO. 200g of CNFT-1 catalyst is injected from the lower side of the gas-solid reactor at a mass flow rate of 10-50g / h, and the apparent gas velocity in each processing space is controlled at 0.3m / s.

[0110] Experimental results show that the average residence time of the CNFT-1 catalyst is approximately 1-8 hours. Along the flow direction, the reaction temperatures of the five stages are controlled sequentially at 170℃, 200℃, 220℃, 240℃, and 255℃, indicating that the reaction temperature in each processing space within the gas-solid reactor is controllable. Along the flow direction of the CNFT-1 catalyst, the He / N2 ratios of the five stages are controlled sequentially at 20:1, 10:1, 8:1, 5:1, and 3:1, indicating that the He / N2 ratio in each stage of the gas-solid reactor is controllable.

[0111] Example 2

[0112] Catalyst replacement data during stable operation of an industrial intermittent equipment: 7 tons of activated catalyst are replaced every 3.5 days, which is equivalent to a catalyst input flow rate of 83.33 kg / h during continuous operation. In a cold-molded gas-solid fluidized bed with a diameter of 400 mm, 100 kg of catalyst was first transferred from the storage tank to the reactor at a relatively high flow rate using a DN25 delivery pipe, taking 34 minutes; subsequently, another 100 kg of catalyst was transferred from the storage tank to the reactor at a relatively high flow rate, taking 126 minutes. This indicates that the equipment can meet the requirement of delivering 83.33 kg of material per hour.

[0113] The relationship between the replacement amount of CNFT-1 catalyst and operating time was derived theoretically, indicating that... Figure 8 As shown, by Figure 8 It can be seen that the areas enclosed by large and small single replacement amounts are equal, and both are equal to the areas enclosed during continuous activation, indicating that the total residence time of the catalyst is the same for the three replacement methods. When activating the CNFT-1 catalyst, a comparison between the batch operation of an industrial batch reactor and the continuous operation of the reactor in Example 1 shows that the total residence time of the CNFT-1 catalyst is comparable in both reactors. Therefore, replacing the batch operation of the industrial batch reactor with the continuous operation of the reactor in Example 1 does not affect the overall performance of the CNFT-1 catalyst.

[0114] Example 3

[0115] The CNFT-1 catalyst was activated in the gas-solid reactor of Example 1. 200g of fresh CNFT-1 catalyst was placed in a catalyst storage tank, first replaced with N2 atmosphere, then replaced with H2 atmosphere, and then the catalyst storage tank was heated to 150°C and kept at a constant temperature.

[0116] The gas-solid reactor was opened, and then fresh CNFT-1 catalyst was continuously transferred into the gas-solid reactor at a mass flow rate of 20 g / h. The process parameters for each activation stage in the gas-solid reactor were then adjusted sequentially as follows:

[0117] First stage: Reaction temperature is constant at 170℃, H2 / CO = 20:1;

[0118] Second stage: Reaction temperature is constant at 200℃, H2 / CO = 10:1;

[0119] Third stage: Reaction temperature is constant at 220℃, H2 / CO = 8:1;

[0120] Fourth stage: Reaction temperature is constant at 240℃, H2 / CO = 5:1;

[0121] Fifth stage: Reaction temperature is constant at 255℃, H2 / CO = 3:1;

[0122] The activated CNFT-1 catalyst was continuously discharged at a mass flow rate of 20 g / h into a discharge tank containing liquid paraffin at 255°C. After the catalyst was fully activated, the liquid paraffin was allowed to cool naturally.

[0123] Example 4

[0124] 10g of activated CNFT-1 catalyst was taken from the unloading tank of Example 3. The Fischer-Tropsch synthesis performance of the activated CNFT-1 catalyst was evaluated under stirring conditions. The main evaluation conditions were: temperature 260℃, pressure 2.0MPa, and fresh gas hourly space velocity 6000h. -1 The exhaust gas is recirculated in the gas phase with a recirculation ratio of 3.5. Testing showed that the activated catalyst sample achieved a total CO conversion rate greater than 94%, a CH4 selectivity of less than 3.0%, and a CO2 selectivity of less than 17%.

[0125] The results from the above embodiments show that the catalyst obtained by the embodiments of the present invention has comparable Fischer-Tropsch synthesis reaction performance to the catalyst obtained by slurry bed activation, while achieving continuous catalyst activation.

[0126] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. An apparatus for continuously activating a catalyst, characterized in that, The device includes; At least one catalyst storage tank for storing fresh catalyst; A gas-solid reactor, connected to the catalyst storage tank, is used to receive fresh catalyst and activation feed gas, and to activate the fresh catalyst to obtain activated catalyst. The gas-solid reactor has at least one baffle plate internally, dividing its internal space into at least two interconnected processing spaces. The baffle plate has overflow ports and / or connecting ports, allowing catalyst material entering the gas-solid reactor to flow from the preceding processing space to the following processing space. The gas-solid reactor is equipped with at least two sets of jet injectors, one set corresponding to each processing space. These jet injectors are used to inject hydrogen and / or CO into the corresponding processing space. The hydrogen-to-carbon volume ratio of the activation gas in the corresponding processing space is adjusted. The processing spaces are arranged sequentially along the catalyst flow direction so that the hydrogen-to-carbon volume ratio gradient of the activation gas in each activation process decreases along the catalyst feed direction. The gas-solid reactor is also equipped with at least two sets of heating and insulation components. Each processing space corresponds to a set of heating and insulation components to control the temperature of the catalyst in the corresponding processing space so that the activation temperature gradient of each activation process increases along the catalyst feed direction. A purifier, connected to the gas-solid reactor, is used to receive the activated gas discharged from the gas-solid reactor and purify the activated gas to obtain purified circulating gas.

2. The device according to claim 1, wherein, The baffles are vertically arranged inside the gas-solid reactor, and there are n-1 baffles in total, which divide the gas-solid reactor into n processing spaces, where n≥2.

3. The device according to claim 1 or 2, wherein the overflow port is located at the upper part of the partition, and the overflow port is circular or polygonal; the connecting port is located at the lower part of the partition, and the connecting port is circular or polygonal; An openable and closable barrier is provided at the overflow port. The barrier can cover the overflow port and can only be opened in the direction of material flow, so that the material can pass through the overflow port in one direction to prevent the catalyst from flowing back. A gas delivery pipe is provided at the connection port to facilitate the transfer of catalyst material from the previous processing space to the next processing space; the gas delivery pipe is connected to the jetting component corresponding to the previous processing space.

4. The device according to claim 1 or 2, wherein, A catalyst inlet is provided on the lower side or top of the gas-solid reactor; If the catalyst inlet is located on the side below the gas-solid reactor, the overflow port of the baffle adjacent to the catalyst inlet is located on the upper part of the baffle; the overflow ports of the baffle are all located on the upper part of the baffle or the overflow ports of the baffle are staggered vertically. If the catalyst inlet is located at the top of the gas-solid reactor, the overflow port of the baffle adjacent to the catalyst inlet is located at the lower part of the baffle, and the overflow ports of the baffle are staggered vertically.

5. The device according to claim 1 or 2, wherein, The overflow port and the connecting port of the partition are arranged alternately; And / or, the heating and insulation component is a heat exchange tube; And / or, each jet assembly includes at least one gas distributor, each gas distributor including a gas distribution main pipe, gas distribution branch pipes and nozzles, the gas distributor being located in the lower region of the processing space; And / or, the gas-solid reactor is provided with 5 interconnected processing spaces, 5 sets of jetting elements and 5 sets of heating and insulation components.

6. The device according to claim 1 or 2, wherein, The equipment for continuously activating the catalyst includes two catalyst storage tanks, namely a first catalyst storage tank and a second catalyst storage tank, and the first catalyst storage tank and the second catalyst storage tank are arranged in parallel.

7. A method for continuously activating a catalyst, characterized in that, The method includes: The catalyst is continuously fed and subjected to segmented activation treatment to obtain activated catalyst and activated gas. The activated gas is then purified to obtain purified circulating gas. The segmented activation treatment process includes multiple activation stages. During each stage of activation treatment, activation gas is injected into the tower to control the hydrogen-to-carbon volume ratio of the activation gas in each stage, and the activation temperature of each stage is controlled accordingly. Along the catalyst feed direction, the hydrogen-to-carbon volume ratio of the activation gas in different stages of activation treatment decreases gradually, while the activation temperature of each stage of activation treatment increases gradually.

8. The method according to claim 7, wherein, The hydrogen-to-carbon volume ratio of the activated gas entering the tower is 3-20:1, and the inlet linear velocity of the activated gas entering the tower is 0.1-0.8 m / s.

9. The method according to claim 8, wherein, The hydrogen-to-carbon volume ratio of the activation gas entering the tower is 3-10:1, and the inlet linear velocity of the activation gas entering the tower is 0.2-0.5 m / s; and / or, the decreasing gradient of the hydrogen-to-carbon volume ratio of the activation gas entering the tower in two adjacent activation treatments is 2-5:1; And / or, the activated gas entering the tower includes activated fresh gas and purified circulating gas, wherein the volume ratio of activated fresh gas to purified circulating gas is 2-5:1; the fresh activated gas is hydrogen and / or CO, and the CO content of the purified circulating gas is not less than 1.2-1.5%; And / or, along the feed direction of the catalyst, the hydrogen-to-carbon volume ratio of the activated fresh gas in different sections of the activation treatment decreases in a gradient. And / or, the hydrogen-to-carbon volume ratio of the activated fresh gas is 10:1 to 1:1; And / or, the decreasing gradient of the hydrogen-carbon volume ratio of the activated fresh gas in two adjacent activation treatments is 2-5:

1.

10. The method according to claim 9, wherein, The volume ratio of the activated fresh air to the purified circulating air is 2-3:

1.

11. The method according to claim 7 or 8, wherein, The segmented activation process has an activation temperature of 130-300℃ and an activation pressure of 1-5MPa.

12. The method according to claim 11, wherein, The segmented activation process has an activation temperature of 150-280℃ and an activation pressure of 2-3MPa. And / or, the activation temperature of the first activation treatment is 140-180℃, and the activation temperature of the two adjacent activation treatments increases by 15-30℃.

13. The method according to claim 7 or 8, wherein, The catalyst is present in each activation treatment for 0.5-2 hours.

14. The method according to claim 13, wherein, The residence time of the catalyst in each stage of the activation treatment is 1-1.5 h; And / or, the method includes: the segmented activation treatment comprising 5 activation treatments, wherein, along the feed direction of the catalyst, the hydrogen-to-carbon volume ratios of the activation gas entering the tower for the 5 activation treatments are 50-20:1, 20-10:1, 10-6:1, 6-4:1, and 4-2:1, respectively; the activation temperatures for the 5 activation treatments are 145-175℃, 175-205℃, 205-235℃, 235-265℃, and 265-295℃, respectively; and the residence time for the 5 activation treatments is the same.

15. The method according to claim 14, wherein, The hydrogen-to-carbon volume ratios of the activation gas entering the activation tower in the five stages of activation treatment are 30:1, 15:1, 8:1, 5:1, and 3:1, respectively. And / or, the activation temperatures for the activation treatment described in Section 5 are 170℃, 200℃, 230℃, 250℃ and 270℃, respectively; And / or, the residence time for the activation treatment described in Section 5 is 1-1.5 h.

16. The method according to claim 7 or 8, wherein, The continuous feeding includes: The fresh catalyst was divided into two parts, and gas replacement and heating / pressurization operations were carried out separately for each part. The two portions of fresh catalyst are fed alternately.

17. The method according to claim 16, wherein, The gas replacement includes: first, multiple replacements with N2; then multiple replacements with H2 or syngas. And / or, the heating and pressurization operation includes: pressure control at 1-5 MPa and temperature control at 80-150°C.

18. The method according to claim 17, wherein, The gas replacement includes: first replacing with N2 2-3 times; then replacing with H2 or syngas 2-3 times.

19. The method according to claim 7 or 8, wherein, The purification process includes: sequentially subjecting the activated gas to condensation and cooling, gas-liquid separation, CO2 removal, pressurization, and dehydration; the volume fraction of CO2 in the purified circulating gas is less than 2%; and the water content is less than 100 ppm by mass.

20. The method according to claim 19, wherein, The purified circulating gas contains 0.2-1% CO2 by volume and 20-50 ppm water by mass.

21. The method according to claim 7 or 8, wherein, The catalyst is a Fischer-Tropsch synthesis iron-based catalyst with an average particle size of 40-150 μm.

22. The method according to claim 21, wherein, The average particle size of the iron-based catalyst particles used in the Fischer-Tropsch synthesis is 60-100 μm. And / or, the method is carried out in the apparatus of any one of claims 1-6, wherein the catalyst flows through each processing space to perform the activation treatment in each segment.

23. A Fischer-Tropsch synthesis apparatus, characterized in that, The apparatus comprises: at least one Fischer-Tropsch slurry bed reactor and a device for continuously activating the catalyst according to any one of claims 1-6, wherein the Fischer-Tropsch slurry bed reactor has an activation catalyst inlet for receiving the activation catalyst.

24. The Fischer-Tropsch synthesis apparatus according to claim 23, wherein, A buffer tank is also provided between the Fischer-Tropsch slurry bed reactor and the equipment for continuously activating the catalyst. The buffer tank is used to receive the activated catalyst separated from the purifier and then send it into the Fischer-Tropsch slurry bed reactor.

25. The Fischer-Tropsch synthesis apparatus according to claim 24, wherein, The Fischer-Tropsch slurry bed reactor has a first discharge port, a second discharge port, and a third discharge port, which are located at the upper, middle, and lower parts of the Fischer-Tropsch slurry bed reactor, respectively.

26. The Fischer-Tropsch synthesis apparatus according to claim 25, wherein, The waste catalyst slurry is discharged from the first discharge port and the second discharge port.

27. A method for Fischer-Tropsch synthesis, characterized in that, The method includes: The Fischer-Tropsch inlet gas is continuously contacted with the activated catalyst prepared by the method described in any one of claims 7-22 in a Fischer-Tropsch slurry bed reactor to carry out the Fischer-Tropsch synthesis reaction. After gas-liquid separation, hydrocarbon products are obtained.

28. The Fischer-Tropsch synthesis method according to claim 27, wherein, The Fischer-Tropsch synthesis reaction is carried out at a temperature of 100-300℃ and a pressure of 0.5-4 MPa.

29. The Fischer-Tropsch synthesis method according to claim 28, wherein, The Fischer-Tropsch synthesis reaction is carried out at a temperature of 250-280℃ and a pressure of 2-3 MPa. And / or, the Fischer-Tropsch feed gas comprises fresh synthesis gas and Fischer-Tropsch recycle gas, wherein the volume hourly space velocity of the fresh synthesis gas is 4000-6000 h⁻¹. -1 The volume ratio of the fresh synthesis gas to the Fischer-Tropsch cycle gas is 2-5:1; the volume ratio of hydrogen to CO in the Fischer-Tropsch inlet gas is 2-5:1; and the volume ratio of hydrogen to CO in the fresh synthesis gas is 1.3-2.5:

1.

30. The Fischer-Tropsch synthesis method according to claim 29, wherein, The volume ratio of the fresh synthesis gas to the Fischer-Tropsch cycle gas is 2-3:1; the volume ratio of hydrogen to CO in the Fischer-Tropsch inlet gas is 3-4:1; and the volume ratio of hydrogen to CO in the fresh synthesis gas is 1.5-1.8:1.

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