Slurry bed reactor with uniform gas holdup distribution

Abstract

The invention provides a slurry bed reactor with uniform gas holdup distribution, which comprises: a cylinder, which is internally provided with an accommodating cavity and is provided with a feed inlet, a gas inlet, a gas outlet and a liquid outlet which are communicated with the accommodating cavity; the gas distributor is arranged in the accommodating cavity, is close to the gas inlet and is circumferentially connected with the inner wall of the accommodating cavity; the plurality of gas holdup distribution adjusting devices are erected in the accommodating cavity on one side, facing the gas outlet, of the gas distributor, each gas holdup distribution adjusting device comprises a gas inlet part, a liquid inlet part, a mixing part and a gas exhaust part, the gas inlet parts, the mixing parts and the gas exhaust parts are sequentially communicated, the gas inlet parts are arranged towards the gas inlet, and the diameters of the cross sections of the gas inlet parts are gradually increased in the direction towards the gas inlet; the air outlet part is arranged towards the air outlet, and the diameter of the cross section is gradually increased in the direction towards the air outlet; the liquid inlet part comprises a first connecting section and a second connecting section which are communicated, the extending direction of the first connecting section is parallel to the connecting line direction of the air inlet and the air outlet, and one end, deviating from the first connecting section, of the second connecting section is communicated with the mixing part.

Description

Technical Field

[0001] The invention relates to the technical field of chemical equipment, and in particular to a slurry bed reactor with uniform gas holdup distribution. Background Art

[0002] As oil prices continue to rise in recent years, people are paying more and more attention to the development of technologies for producing alternative oil products. Synthesis gas is produced from coal, natural gas or other substances, and then the synthesis gas is treated through water-gas shift and synthesis gas purification processes according to the requirements of the Fischer-Tropsch synthesis catalyst for synthesis gas. The treated synthesis gas is used as a raw material to produce hydrocarbons through Fischer-Tropsch synthesis, while oxygen-containing compounds are produced as by-products. Then, mature oil processing technology is used for processing to produce high-quality environmentally friendly oil products. The development of Fischer-Tropsch synthesis technology is of great significance to the development of production technology for alternative oil products.

[0003] The Fischer-Tropsch synthesis reactor is the core reactor of the Fischer-Tropsch synthesis technology. Currently, the three-phase slurry bed reactor that can produce more hydrocarbon products is widely used at home and abroad. The slurry bed reactor has the advantages of uniform and easy control of temperature, wide gas velocity operation range, high product alpha value, and online catalyst replacement. However, as the reaction proceeds, the reaction bubbles in the reactor continue to coalesce and break, forming more and more large bubbles, resulting in an obvious uneven distribution of gas holdup in the reactor axis. From the bottom of the reactor to the top, the average size of the bubbles is larger, and the more large bubbles there are, the lower the gas holdup, and then the gas-liquid mass transfer area is relatively smaller, and the conversion rate of the feed gas is reduced, which ultimately leads to a reduction in the production capacity of the upper part of the reactor. Summary of the invention

[0004] In view of this, the present invention provides a slurry bed reactor with uniform gas holdup distribution to solve the above technical problems.

[0005] The slurry bed reactor with uniform gas holdup distribution provided by the present invention comprises:

[0006] A cylinder body, wherein a containing cavity is arranged in the cylinder body, and a feed port, an air inlet, an air outlet and a liquid outlet are formed through the cylinder body and connected to the containing cavity;

[0007] A gas distributor, the gas distributor is arranged in the accommodating chamber and close to the gas inlet, and the circumference of the gas distributor is connected to the circumference of the inner wall of the accommodating chamber;

[0008] A plurality of gas content distribution and adjustment devices are installed in the accommodating chamber on the side of the gas distributor facing the gas outlet, and each of the gas content distribution and adjustment devices includes an air inlet, a liquid inlet, a mixing section and an exhaust section, wherein the air inlet, the mixing section and the exhaust section are sequentially connected and arranged, the air inlet is arranged toward the air inlet, and the cross-sectional diameter gradually increases in the direction toward the air inlet, the air outlet is arranged toward the air outlet, and the cross-sectional diameter gradually increases in the direction toward the air outlet; the liquid inlet includes a first connecting section and a second connecting section that are connected, the extension direction of the first connecting section is parallel to the connecting direction of the air inlet and the air outlet, and the end of the second connecting section that is away from the first connecting section is connected to the mixing section.

[0009] Optionally, the gas content distribution regulating device further comprises: a shear plate, wherein the shear plate is provided with shear holes extending therethrough, and is disposed in the exhaust section, wherein the shear plate is circumferentially connected to the inner wall of the exhaust section.

[0010] Optionally, the ratio of the cross-sectional diameter of the shear plate to the cross-sectional diameter of the mixing portion is 1:1-4:1.

[0011] Optionally, the gas content distribution regulating device further includes: a gathering portion, which is a hollow structure, connected to an end of the first connecting section away from the second connecting section, and the cross-sectional diameter of the gathering portion gradually increases in the direction toward the gas outlet.

[0012] Optionally, a ratio of a cross-sectional diameter of the gathering portion toward one end of the air outlet to a cross-sectional diameter of the gathering portion toward one end of the air inlet is 3:1-10:1.

[0013] Optionally, the ratio of the cross-sectional diameter of the liquid inlet portion to the cross-sectional diameter of the mixing portion is 1:8-1:2.

[0014] Optionally, the slurry bed reactor with uniform gas holdup distribution further includes: a heat exchanger, wherein the heat exchanger is disposed in the accommodating cavity on the side of the gas distributor facing the gas outlet.

[0015] Optionally, the slurry bed reactor with uniform gas holdup distribution further includes: a liquid-solid separator, and the liquid-solid separator is arranged at the liquid outlet.

[0016] Optionally, the slurry bed reactor with uniform gas content distribution further includes: a gas-liquid separator, and the gas-liquid separator is arranged at the gas outlet.

[0017] Optionally, the slurry bed reactor with uniform gas holdup distribution further includes: a circulation pipeline, a first end of the circulation pipeline is connected to the gas outlet, and a second end of the circulation pipeline is connected to the gas inlet.

[0018] Compared with the prior art, the above technical solution provided by the present invention has at least the following beneficial effects:

[0019] By adopting the slurry bed reactor with uniform gas holdup distribution of the present invention, with the help of the gas holdup distribution regulating device arranged in the middle of the cylinder, the larger bubbles rising to this place are sheared into smaller bubbles, and the gas distribution in the upper part of the reactor is restored to the gas distribution state at the bottom of the reactor to the greatest extent, thereby solving the problem of uneven gas holdup distribution in the upper and lower sections of the reactor, increasing the gas-liquid mass transfer area in the upper part of the reactor, improving the conversion rate of the raw gas, and finally improving the total production capacity of the reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of a slurry bed reactor with uniform gas holdup distribution according to an embodiment of the present invention;

[0021] Figure 2 for Figure 1 A schematic diagram of a gas holdup distribution regulating device in the reactor shown;

[0022] Figure 3 for Figure 1 A distribution diagram of a gas holdup distribution regulating device in the reactor shown;

[0023] Figure 4 for Figure 1 The radial gas holdup distribution curve at the position 1m above and below the gas holdup distribution regulating device in the reactor shown;

[0024] Figure 5 for Figure 1 A curve diagram showing the variation of the steam volume discharged from the heat exchangers on the upper and lower sides of the gas holdup distribution regulating device in the reactor over time;

[0025] Figure 6 The radial gas holdup distribution curve of the reactor center when no gas holdup distribution adjustment device is provided;

[0026] Figure 7 This is a graph showing the change in the amount of steam discharged from the heat exchangers located in the upper and lower sections of the reactor over time when the gas content distribution adjustment device is not installed.

[0027] Reference numerals:

[0028] 1: cylinder; 101: air inlet; 102: air outlet; 103: liquid outlet; 2: gas distributor; 3: gas content distribution regulating device; 301: air inlet; 302: liquid inlet; 3021: first connecting section; 3022: second connecting section; 303: mixing section; 304: exhaust section; 305: shear plate; 306: gathering section; 4: heat exchanger; 5: liquid-solid separator; 6: gas-liquid separator. DETAILED DESCRIPTION

[0029] The embodiments of the present invention will be further described below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only simplified descriptions for the convenience of describing the present invention, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0030] Figure 1 A schematic diagram of a slurry bed reactor with uniform gas holdup distribution according to an embodiment of the present invention; Figure 2 for Figure 1 Schematic diagram of the gas content distribution adjustment device in the reactor shown.

[0031] like Figure 1 and Figure 2 As shown, the slurry bed reactor with uniform gas content distribution includes a cylinder 1, a gas distributor 2 and a plurality of gas content distribution adjustment devices 3.

[0032] The cylinder 1 is provided with a containing cavity, and the cylinder 1 is penetrated with a feed port, an air inlet 101, an air outlet 102 and a liquid outlet 103 connected to the containing cavity; the gas distributor 2 is provided in the containing cavity and is arranged close to the air inlet 101, and the circumference of the gas distributor 2 is connected to the circumference of the inner wall of the containing cavity; a plurality of gas content distribution adjustment devices 3 are set up in the containing cavity on the side of the gas distributor 2 facing the air outlet 102, and each of the gas content distribution adjustment devices 3 includes an air inlet part 301, a liquid inlet part 302, a mixing part 303 and an exhaust part 304, wherein the air inlet part 301, the mixing part 303 and the exhaust part 304 03 and the exhaust section 304 are connected in sequence, the air inlet section 301 is arranged toward the air inlet 101, and the cross-sectional diameter gradually increases in the direction toward the air inlet 101, and the air outlet section is arranged toward the air outlet 102, and the cross-sectional diameter gradually increases in the direction toward the air outlet 102; the liquid inlet section 302 includes a first connecting section 3021 and a second connecting section 3022 that are connected, the extension direction of the first connecting section 3021 is parallel to the connecting direction of the air inlet 101 and the air outlet 102, and the end of the second connecting section 3022 that is away from the first connecting section 3021 is connected to the mixing section 303.

[0033] When in use, a plurality of the gas content distribution adjustment devices 3 are installed at intervals in the middle of the cylinder 1, liquid wax and catalyst are pre-loaded in the cylinder 1, and raw gas (synthesis gas of carbon monoxide and hydrogen) is input through the gas inlet 101. After passing through the gas distributor 2, the raw gas is decomposed into small bubbles, which are evenly distributed in the cylinder 1 and start to react under the action of the catalyst. As the reaction proceeds, the reaction bubbles continuously gather and break, forming more and more large bubbles. When the large bubbles rise to the gas content distribution regulating device 3, they enter the gas inlet 301 together with the fluid and flow through the mixing section 303. At the same time, the gas-liquid mixed fluid in the cylinder 1 enters the first connecting section 3021 in the vertical direction of the liquid inlet 302, and due to the density difference, the gas in the gas-liquid mixed fluid rises and is discharged in the first connecting section 3021, leaving only the liquid to flow into the second connecting section 3022, and then flow into the mixing section 303 through the second connecting section 3022, impacting the bubbles flowing through the gas inlet 301 to the mixing section 303, shearing the larger bubbles into smaller bubbles, and the sheared smaller bubbles enter the exhaust section 304 through the mixing section 303, and then re-discharged into the containing chamber to continue to participate in the reaction. After the reaction is completed, the generated heavy products are discharged through the liquid outlet 103, and the tail gas is discharged through the gas outlet 102.

[0034] By adopting the slurry bed reactor with uniform gas holdup distribution of the present invention, with the help of the gas holdup distribution regulating device 3 arranged in the middle of the cylinder 1, the larger bubbles rising to this point are sheared into smaller bubbles, and the gas distribution in the upper part of the reactor is restored to the gas distribution state at the bottom of the reactor to the greatest extent, thereby solving the problem of uneven gas holdup distribution in the upper and lower sections of the reactor, increasing the gas-liquid mass transfer area in the upper part of the reactor, improving the conversion rate of the raw gas, and finally improving the total production capacity of the reactor.

[0035] like Figure 1 As shown, in this embodiment, the gas inlet 101 is opened at the center of the bottom end of the cylinder 1, the gas outlet 102 is opened at the center of the top end of the cylinder 1, and the liquid outlet 103 is opened at the center of the left wall of the cylinder 1. The gas distributor 2 is close to the bottom end of the cylinder 1, perpendicular to the axial direction of the cylinder 1, and covers the cross-section of the cylinder 1 to ensure that the raw gas entering the cylinder 1 can pass through the gas distributor 2 and be decomposed into small bubbles. When the bubbles react and rise to the middle of the cylinder 1, the bubble size distribution is uneven, that is, the upper and lower sections of the cylinder 1 begin to show obvious uneven gas content distribution. Therefore, a plurality of gas content distribution adjustment devices 3 are set in the middle of the cylinder 1. As shown Figure 1 , Figure 2As shown, the air inlet 301, the mixing section 303 and the exhaust section 304 are connected in sequence, and the cross-sections are all circular, and the cross-sectional diameters of the air inlet 301 and the exhaust section 304 gradually decrease in the direction toward the mixing section 303, and the cross-sectional diameters of the three are the same at the connection, thereby forming a venturi tube structure, forming a negative pressure inside, and allowing the mixed fluid of gas and liquid to smoothly enter the mixing section 303 through the air inlet 301 without the need for external power, and at the same time allowing the liquid to smoothly enter the mixing section 303 through the liquid inlet 302 connected to the mixing section 303, thereby shearing the large bubbles entering the mixing section 303, and the sheared small bubbles are smoothly discharged into the cylinder 1 along with the fluid through the exhaust section 304. In the present embodiment, the second connecting section 3022 is vertically arranged with the mixing section 303, so that the fluid entering the mixing section 303 through the second connecting section 3022 is in vertical contact with the large bubbles entering the mixing section 303 through the air inlet 301, so as to achieve a better shearing effect of the large bubbles. In the present embodiment, the first connecting section 3021 is vertically connected with the second connecting section 3022. In order to reduce the internal fluid resistance, the connection between the two can be set to an arc transition. In order to ensure the normal reaction, the raw gas needs to enter the cylinder 1 at a gas velocity of 5-40cm / s after passing through the gas distributor 2 to participate in the reaction, and the gas phase flow rate is maintained between 8-25cm / s when it is discharged from the air outlet 102 after the reaction is completed. In order for the gas-liquid mixture to enter the air inlet 301 smoothly, and to be able to be discharged from the exhaust section 304 smoothly after the large bubbles are sheared into small bubbles, Figure 2 The angles between the left and right oblique sides of the longitudinal sections of the air inlet portion 301 and the exhaust portion 304 and the horizontal plane are both set to 20-75°, and more preferably 30-60°.

[0036] Figure 3 for Figure 1 The distribution diagram of the gas content distribution regulating device 3 in the reactor is shown. In the cylinder 1, as the reaction proceeds, the bubbles continuously gather and break to form large bubbles during the rising process, which not only causes the upper and lower sections of the cylinder 1 to show uneven gas content distribution, but also in the radial direction of the cylinder 1, the bubbles in the middle are smaller and the bubbles around are larger, and there is an uneven gas content distribution with high gas content in the middle and low gas content around in the radial direction. Therefore, in order to solve the uneven gas content distribution in the axial upper and lower sections and in the radial direction of the cylinder 1 at the same time, a plurality of the gas content distribution regulating devices 3 are arranged in the middle of the cylinder 1, and two concentric rings are arranged around the axis of the cylinder 1, six gas content distribution regulating devices 3 are evenly arranged in the ring close to the axis of the cylinder 1, and twelve gas content distribution regulating devices 3 are evenly arranged in the ring away from the axis of the cylinder 1.

[0037] According to the actual application, the shape and size of the cylinder 1, the specific specifications and models of the gas distributor 2, the number of the gas content distribution adjustment device 3 and the specific arrangement position in the cylinder 1 can be adjusted. The gas distributor 2 and the venturi tube structure are both mature existing technologies, and the specific working principles of the two are not repeated here.

[0038] Optionally, the gas holdup distribution regulating device 3 further comprises a shear plate 305, the shear plate 305 is provided with shear holes, and is arranged in the exhaust section 304, and the circumference of the shear plate 305 is connected to the circumference of the inner wall of the exhaust section 304. The large bubbles entering the mixing section 303 are sheared by the fluid introduced into the mixing section 303 through the liquid inlet section 302 to form small bubbles. This arrangement enables the sheared small bubbles to undergo secondary liquid phase shearing through the shear holes provided through the shear plate 305 when passing through the shear plate 305, thereby obtaining fine bubbles of smaller size, thereby further increasing the gas-liquid contact area.

[0039] like Figure 2 As shown, in this embodiment, the shear plate 305 is arranged at a lower center position in the exhaust portion 304 and is arranged perpendicular to the axial direction of the exhaust portion 304. The shape of the shear hole can be at least one of a circle, a triangle, a square, and a rectangle, and the arrangement type can be at least one of a triangle arrangement or a square arrangement, and the equivalent diameter is 2-5 mm. According to actual application conditions, the shape and size of the shear plate 305, the specifications and quantity of the shear holes, and the specific arrangement position of the shear plate 305 in the exhaust portion 304 can all be adjusted.

[0040] Optionally, the ratio of the cross-sectional diameter of the shear plate 305 to the cross-sectional diameter of the mixing portion 303 is 1:1-4:1. This arrangement can more fully perform secondary shearing on the small bubbles discharged from the mixing portion 303 after the primary shearing.

[0041] like Figure 2 As shown, in this embodiment, the shear plate 305 is arranged at the lower center of the exhaust section 304, and the cross-sectional diameter is approximately twice the cross-sectional diameter of the mixing section 303. The position of the shear plate 305 can be adjusted up and down to adapt to its different sizes.

[0042] Optionally, the gas holdup distribution regulating device 3 further includes a gathering portion 306, which is a hollow structure and is connected to one end of the first connecting section 3021 away from the second connecting section 3022, and the cross-sectional diameter of the gathering portion 306 gradually increases in the direction toward the gas outlet 102. This arrangement can more quickly introduce the fluid into the liquid inlet portion 302 by means of the gathering portion 306 with an approximately inverted cone-shaped opening, and also facilitates the gas entering the liquid inlet portion 302 to be discharged upward more quickly.

[0043] In this embodiment, the cross section of the gathering portion 306 is circular, and the end with a smaller cross section is connected to the liquid inlet portion 302, and the whole is an inverted cone. According to actual application conditions, the specific shape and size of the gathering portion 306 can be adjusted.

[0044] Optionally, the ratio of the cross-sectional diameter of the end of the gathering part 306 facing the gas outlet 102 to the cross-sectional diameter of the end facing the gas inlet 101 is 3:1-10:1. This arrangement facilitates the fluid in the cylinder 1 to flow into the gathering part 306 more quickly, and is also conducive to the rapid and sufficient discharge of the gas entering the liquid inlet 302 through the gathering part 306 with the divergent opening after rising. In order to achieve a more optimized effect, the ratio of the cross-sectional diameters of the ends of the gathering part 306 facing the gas outlet 102 and the gas inlet 101 can be set to 5:1-8:1.

[0045] like Figure 2 As shown, in this embodiment, the gathering portion 306 is configured to be an approximate inverted cone. In order to allow the fluid to flow smoothly into the liquid inlet portion 302 along the gathering portion 306, the angle between the oblique sides of the left and right side walls of the longitudinal section of the gathering portion 306 and the horizontal plane is set to 20-75°, and more preferably 30-60°.

[0046] Optionally, the ratio of the cross-sectional diameter of the liquid inlet 302 to the cross-sectional diameter of the mixing section 303 is 1:8-1:2. This arrangement can not only utilize the internal negative pressure formed by the Venturi structure to fully draw the fluid flowing into the liquid inlet 302 into the mixing section 303, but also make the fluid drawn into the mixing section 303 sufficiently shear the large bubbles entering the mixing section 303.

[0047] Optionally, the slurry bed reactor with uniform gas holdup distribution further includes a heat exchanger 4, which is disposed in the accommodating cavity on the side of the gas distributor 2 facing the gas outlet 102. Fischer-Tropsch synthesis is an exothermic reaction, and the heat in the cylinder 1 is absorbed by the heat exchanger 4 and then taken out of the cylinder 1, which can maintain the temperature in the cylinder 1 stable, and is conducive to the continuous and normal progress of the reaction.

[0048] like Figure 1 As shown, in this embodiment, two groups of heat exchangers 4 are arranged in the cylinder 1, respectively located in the upper section and the lower section of the cylinder 1, and the gas content distribution regulating device 3 is arranged between the two. The heat exchanger 4 adopts heat exchange tubes, which fill the radial space in the cylinder 1. The liquid inlet pipe and the liquid outlet pipe of the heat exchange tube respectively penetrate the cylinder 1 and are connected with the external circulation equipment. High-temperature water flows in the heat exchange tubes, absorbing the heat released by the reaction in the cylinder 1 to produce phase change, so as to use the latent heat of phase change of high-temperature water to bring out the heat in the cylinder 1 and maintain the temperature in the cylinder 1 stable. The amount of phase change to steam in the heat exchange tubes can also be measured. Because Fischer-Tropsch synthesis is an exothermic reaction, the larger the amount of steam, the more heat is absorbed, the more heat is released by the reaction in the cylinder 1, and the more fully the reaction is carried out, which further indicates that the conversion rate of the raw gas in the cylinder 1 is high and the gas content is high. After the gas holdup distribution adjusting device 3 is provided, there is no significant difference in the gas holdup distribution between the upper and lower sections of the cylinder 1, and there is no significant difference in the total amount of steam discharged from the two groups of heat exchange tubes located in the upper and lower sections of the cylinder 1. According to the actual application, the heat exchanger 4 can be of any specification and model, as long as it can take away the heat generated by the reaction in the cylinder 1 and ensure the continuous and normal progress of the reaction.

[0049] Optionally, the slurry bed reactor with uniform gas holdup distribution further comprises a liquid-solid separator 5, which is arranged at the liquid outlet 103. This arrangement filters and separates the liquid-solid mixture discharged from the cylinder 1 after the reaction is completed, prevents the solid catalyst from being discharged, and saves costs. The liquid-solid separator 5 can adopt any structural form that can separate liquid and solid, as long as the solid catalyst can be intercepted in the cylinder 1.

[0050] Optionally, the slurry bed reactor with uniform gas holdup distribution further comprises a gas-liquid separator 6, which is arranged at the gas outlet 102. This arrangement filters the liquid contained in the gas discharged from the cylinder 1 after the reaction is completed, prevents the liquid from being discharged, and keeps the discharged gas dry. The gas-liquid separator 6 can adopt any structural form that can separate gas and liquid.

[0051] Optionally, the slurry bed reactor with uniform gas holdup distribution further includes a circulation pipeline (not shown), a first end of the circulation pipeline is connected to the gas outlet 102, and a second end of the circulation pipeline is connected to the gas inlet 101. The tail gas discharged through the gas outlet 102 contains part of the unreacted raw gas, and the tail gas is transported back to the cylinder 1, so that the raw gas in the tail gas can re-participate in the reaction, which is conducive to improving the utilization rate of the raw gas.

[0052] During the reaction, fresh raw gas is continuously delivered to the cylinder 1. In order to maintain the pressure in the cylinder 1 stable, part of the tail gas discharged through the outlet 102 is delivered to subsequent equipment for treatment, and part is delivered back to the cylinder 1 through the circulation pipeline.

[0053] The following is further described in conjunction with the embodiments and comparative examples:

[0054] Example

[0055] The cylinder 1 has a diameter of 5.8m, a tangential height of 40m, and a liquid level control height of 32m. A group of heat exchangers 4 in the form of heat exchange tubes are respectively arranged in the upper and lower sections of the cylinder 1, and the bottom of the lower heat exchange tube is 500mm away from the lower end of the cylinder 1. Between the two groups of heat exchangers 4, a plurality of gas content distribution adjustment devices 3 are arranged in the middle of the cylinder 1. The plurality of gas content distribution adjustment devices 3 are distributed in two layers along radial concentric circles, with six gas content distribution adjustment devices 3 evenly spaced in the inner layer and twelve gas content distribution adjustment devices 3 evenly spaced in the outer layer. Figure 1 and Figure 3 shown.

[0056] The pressure of the gas phase entering the reactor is 2.9Mpa, and the reactor temperature is 260°C. The reactor uses an iron-based Fischer-Tropsch synthesis catalyst, the catalyst storage in the reactor is 26 tons in a stable state, and the volumetric space velocity of the raw gas is 5000h -1 Except for the exhaust gas, most of it is recycled back to the reactor. The amount of circulating gas can ensure that the superficial gas velocity of the gas at the reactor inlet 101 is stable at 0.30m / s.

[0057] The test results show that the catalyst performance of the reactor can maintain a total CO conversion rate of more than 98%, a methane selectivity of less than 3%, and a C5+ product yield of 170g / Nm 3 Raw gas; carbon dioxide selectivity is stabilized at less than 18%; the C5+ product production capacity of a single reactor reaches 210,000 tons / year.

[0058] Due to the presence of the gas holdup distribution adjustment device 3, the radial gas holdup distribution in the cylinder 1 has undergone a relatively large change. The optical fiber probe method is used to measure and obtain: Figure 4 The radial gas holdup distribution curve at the position 1m above and below the gas holdup distribution regulating device 3 in the reactor shown in the figure, wherein r is the distance between the point where the gas holdup is measured and the axis of the cylinder 1, and R is the radius of the cylinder 1. The larger the r / R, the farther the point where the gas holdup is measured is from the axis of the cylinder 1. Figure 4It can be seen that at a position 1 m below the gas holdup distribution adjusting device 3, the difference between the gas holdup at the axis of the cylinder 1 and the gas holdup near the inner wall of the cylinder 1 is relatively large, indicating that the gas holdup distribution in the radial direction is not uniform enough, while at a position 1 m above the gas holdup distribution adjusting device 3, after the shearing action of the gas holdup distribution adjusting device 3 on large bubbles, the difference between the gas holdup at the axis of the cylinder 1 and the gas holdup near the inner wall of the cylinder 1 is very small, indicating that after the large bubbles are sheared into small bubbles, the distribution of the gas holdup in the radial direction is relatively uniform.

[0059] The amount of steam generated in the upper and lower groups of heat exchange tubes was measured and obtained. Figure 5 The graph of the steam volume discharged from the heat exchangers 4 on the upper and lower sides of the gas content distribution regulating device 3 is shown as a function of time. Due to the presence of the gas content distribution regulating device 3, the large bubbles rising between the two groups of heat exchange tubes are sheared into small bubbles, the gas content of the upper part of the cylinder 1 and the conversion rate of the raw gas are increased, and the gas content distribution of the upper and lower sections of the cylinder 1 is relatively uniform, so that the upper and lower sections of the cylinder 1 can fully react. Figure 5 It can be seen from the test results that during the stable operation of the reactor (taking about 200 hours as an example), the amount of steam brought out by the heat exchanger 4 in the upper and lower sections of the cylinder 1 is not much different, with a numerical difference of about 30 t / h, which means that the upper and lower sections of the cylinder 1 have both undergone sufficient reactions, releasing similar heat, and the raw gas conversion rate is not much different.

[0060] Comparative Example

[0061] The cylinder 1 has a diameter of 5.8 m, a tangential height of 40 m, and a liquid level control height of 32 m. A set of heat exchangers 4 in the form of heat exchange tubes is provided in the upper and lower sections of the cylinder 1, and the bottom of the lower heat exchange tube is 500 mm away from the lower end of the cylinder 1. The gas holdup distribution regulating device 3 is not provided between the two sets of heat exchangers 4.

[0062] The pressure of the gas phase entering the reactor is 2.9Mpa, and the reactor temperature is 260°C. The reactor uses an iron-based Fischer-Tropsch synthesis catalyst, the catalyst storage in the reactor is 26 tons in a stable state, and the volumetric space velocity of the raw gas is 5000h -1 Except for the exhaust gas, most of it is recycled back to the reactor. The amount of circulating gas can ensure that the superficial gas velocity of the gas at the reactor inlet 101 is stable at 0.30m / s.

[0063] The test results show that the catalyst performance of the reactor can maintain a total CO conversion rate of 96%, a methane selectivity of 3.5%, and a C5+ product yield of 160g / Nm 3Raw gas; carbon dioxide selectivity is stabilized at 20%; the C5+ product capacity of a single reactor reaches 166,000 tons / year, which is lower than the capacity of the reactor equipped with the gas content distribution regulating device 3.

[0064] The radial gas holdup distribution at the middle position of the two sets of heat exchangers 4 was measured by the optical fiber probe method and obtained Figure 6 The radial gas holdup distribution curve of the reactor center when the gas holdup distribution regulating device 3 is not provided is shown in FIG. Figure 6 It can be seen that the radial gas holdup distribution is obviously uneven, and the gas holdup at the center of the cylinder 1 is obviously higher than that at the side wall.

[0065] The amount of steam generated in the upper and lower groups of heat exchange tubes was measured and obtained. Figure 7 The graph shown is a graph of the variation of the amount of steam discharged from the heat exchangers 4 located in the upper and lower sections of the reactor over time when the gas holdup distribution regulating device 3 is not provided. Figure 7 The test results show that during the stable operation of the reactor (taking about 200 hours as an example), the amount of steam brought out by the heat exchangers 4 in the upper and lower sections of the reactor is quite different. The heat brought out by the heat exchanger 4 in the lower part of the reactor is significantly higher than that in the upper part of the reactor. The numerical difference is about 100t / h, indicating that the degree of Fischer-Tropsch synthesis reaction in the upper and lower sections of the reactor, that is, the conversion rate of raw gas, is quite different.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A slurry bed reactor with uniform gas holdup distribution, characterized in that: include: A cylinder body, wherein a containing cavity is arranged in the cylinder body, and a feed port, an air inlet, an air outlet and a liquid outlet are formed through the cylinder body and connected to the containing cavity; A gas distributor, the gas distributor is arranged in the accommodating chamber and close to the gas inlet, and the circumference of the gas distributor is connected to the circumference of the inner wall of the accommodating chamber; A plurality of gas content distribution and adjustment devices are installed in the accommodating chamber on the side of the gas distributor facing the gas outlet, and each of the gas content distribution and adjustment devices includes an air inlet, a liquid inlet, a mixing section and an exhaust section, wherein the air inlet, the mixing section and the exhaust section are sequentially connected and arranged, the air inlet is arranged toward the air inlet, and the cross-sectional diameter gradually increases in the direction toward the air inlet, the air outlet is arranged toward the air outlet, and the cross-sectional diameter gradually increases in the direction toward the air outlet; the liquid inlet includes a first connecting section and a second connecting section that are connected, the extension direction of the first connecting section is parallel to the connecting direction of the air inlet and the air outlet, and the end of the second connecting section that is away from the first connecting section is connected to the mixing section.

2. The slurry bed reactor with uniform gas holdup distribution according to claim 1, characterized in that: The gas holdup distribution regulating device further comprises: A shear plate is provided with a shear hole through the shear plate, and is arranged in the exhaust portion. The circumference of the shear plate is connected to the circumference of the inner wall of the exhaust portion.

3. The slurry bed reactor with uniform gas holdup distribution according to claim 2, characterized in that: The ratio of the cross-sectional diameter of the shear plate to the cross-sectional diameter of the mixing portion is 1:1-4:

1.

4. The slurry bed reactor with uniform gas holdup distribution according to any one of claims 1 to 3, characterized in that: The gas holdup distribution regulating device further comprises: The gathering portion is a hollow structure, connected to an end of the first connecting section away from the second connecting section, and the cross-sectional diameter of the gathering portion gradually increases in a direction toward the air outlet.

5. The slurry bed reactor with uniform gas holdup distribution according to claim 4, characterized in that: The ratio of the cross-sectional diameter of the end portion of the gathering portion toward the air outlet to the cross-sectional diameter of the end portion of the gathering portion toward the air inlet is 3:1-10:

1.

6. The slurry bed reactor with uniform gas holdup distribution according to any one of claims 1 to 3, characterized in that: The ratio of the cross-sectional diameter of the liquid inlet portion to the cross-sectional diameter of the mixing portion is 1:8-1:

2.

7. The slurry bed reactor with uniform gas holdup distribution according to any one of claims 1 to 3, characterized in that: Also includes: A heat exchanger is arranged in the accommodating cavity on the side of the gas distributor facing the gas outlet.

8. The slurry bed reactor with uniform gas holdup distribution according to any one of claims 1 to 3, characterized in that: Also includes: A liquid-solid separator is arranged at the liquid outlet.

9. The slurry bed reactor with uniform gas holdup distribution according to any one of claims 1 to 3, characterized in that: Also includes: A gas-liquid separator is arranged at the gas outlet.

10. The slurry bed reactor with uniform gas holdup distribution according to any one of claims 1 to 3, characterized in that: Also includes: A circulation pipeline, wherein a first end of the circulation pipeline is connected to the air outlet, and a second end of the circulation pipeline is connected to the air inlet.

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