A full-fraction gasoline hydrogenation device and method

Abstract

The present invention discloses a full-fraction gasoline hydrogenation device and method. After the full-fraction gasoline is pre-hydrogenated, the product is fractionated into a light fraction and a heavy fraction; the light fraction undergoes an aromatization reaction; the heavy fraction descends into a hydrodesulfurization reaction zone, and undergoes a hydrodesulfurization reaction with the upward hydrogen in multiple catalyst beds in stages, and the generated hydrogen sulfide and unreacted gas phase feed are discharged from the top of the hydrogenation reactor through an independent gas phase channel, and a heavy gasoline product is obtained at the bottom of the reactor. The method of the present invention allows the light component and hydrogen sulfide to quickly leave the system and no longer participate in the reaction, effectively preventing hydrogen sulfide from further combining with olefins to generate mercaptans, and avoiding the problem of excessive mercaptan content in gasoline after desulfurization; at the same time, the reaction product quickly leaves the reactor, which is conducive to the reaction proceeding to the right, thereby improving the reaction rate and liquid yield.

Description

Technical Field

[0001] The invention belongs to the field of gasoline production by hydrogenation refining, and more specifically, relates to a hydrogenation device and method for producing low-sulfur, low-olefin clean gasoline from full-fraction gasoline. Background Art

[0002] In recent years, with the increasingly stringent environmental regulations, ultra-low sulfur and low olefin content in gasoline has become a development trend in developed countries and regions around the world. The latest Beijing 6B motor gasoline standard requires that the olefin volume fraction should not exceed 12% and the sulfur mass fraction should be lower than 10ppm. Although the traditional hydrodesulfurization method can effectively remove sulfides from gasoline and reduce the olefin content of gasoline, the olefins in gasoline will be saturated with hydrogen to form low-octane alkanes, causing the octane number of gasoline to drop sharply. Therefore, in the process of gasoline hydrodesulfurization, especially in the process of reducing olefins, how to maintain and restore the octane number becomes a difficulty in technical development.

[0003] In recent years, several typical FCC gasoline selective hydrodesulfurization technologies have been developed at home and abroad. The French Petroleum Research Institute has developed Prime G + technology, which is characterized by pre-fractionating the full-fraction FCC gasoline into light fractions, middle fractions and heavy fractions, using a single-stage hydrodesulfurization catalyst to treat the middle fractions and heavy fractions, and then blending the desulfurized products with the light fractions treated with sweetening alcohols. ExxonMobil has developed a deep hydrodesulfurization combined with octane recovery technology, which is characterized by selective hydrogenation technology or non-selective hydrogenation technology combined with cracking, isomerization and other octane recovery reactions, which can well compensate for the octane loss caused by olefin and aromatic saturation during hydrodesulfurization. Experiments have shown that due to the high olefin content of FCC gasoline in my country, which is as high as 40%~50%, it is difficult for existing technologies to achieve satisfactory results.

[0004] Sinopec's S-zorb adsorption desulfurization technology uses an adsorption desulfurization method to treat full-fraction catalytic cracking gasoline. Compared with the raw material, its product has a significantly lower sulfur content, but its density, distillation range and other properties remain basically unchanged, olefins are slightly reduced, alkanes are slightly increased, and the octane number loss is less than one unit. However, this method cannot significantly reduce the olefin content in the product, and cannot solve the problem of reducing olefins for catalytic cracking gasoline with a high olefin content. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a full-fraction gasoline hydrogenation device and method. The method can produce clean gasoline with an olefin volume fraction of no more than 12% and a sulfur mass fraction of less than 10ppm from low-quality gasoline, with less octane number loss, simple process flow, and energy saving and consumption reduction.

[0006] According to a first aspect of the present invention, there is provided a full-fraction gasoline hydrogenation reactor.

[0007] A full-fraction gasoline hydrogenation reactor of the present invention comprises, from top to bottom, an aromatization reaction zone, a separation chamber and a hydrodesulfurization reaction zone;

[0008] The separation chamber is used to separate the full-fraction gasoline raw material into a light fraction and a heavy fraction, the light fraction enters the aromatization reaction zone upward, and the heavy fraction enters the hydrodesulfurization reaction zone downward;

[0009] The aromatization reaction zone is used to carry out aromatization and alkylation reactions on the low-carbon olefins in the light fraction, and simultaneously carry out hydrodesulfurization reactions;

[0010] The hydrodesulfurization reaction zone receives the heavy fraction descending from the separation chamber as a liquid feed, and the liquid feed flows from top to bottom through each catalyst bed arranged in the hydrodesulfurization reaction zone; the preheated hydrogen enters each catalyst bed from the bottom to the top uniformly from the bottom of each catalyst bed; the liquid feed and hydrogen undergo a hydrodesulfurization reaction on the hydrorefining catalyst; the hydrogen sulfide generated by the hydrodesulfurization and the unreacted gaseous feed are discharged from the top of the hydrodesulfurization reaction zone through an independent gas phase channel, and the liquid product obtained by hydrorefining is discharged from the hydrodesulfurization reaction zone (hydrogenation reactor).

[0011] Furthermore, in the above technical solution, the height of the separation chamber is generally 10% to 30% of the height of the hydrogenation reactor. The ratio of the height of the aromatization reaction zone to the height of the hydrodesulfurization reaction zone is 5:1 to 1:8, preferably 3:1 to 1:6.

[0012] Furthermore, in the above technical solution, fillers or trays are placed in the separation chamber, and a selective hydrogenation catalyst can also be placed. Preferably, a selective hydrogenation catalyst is placed to remove dienes in the whole-fraction gasoline and separate the whole-fraction gasoline, with the light fraction entering the aromatization reaction zone upward and the heavy fraction entering the hydrodesulfurization reaction zone downward.

[0013] Furthermore, in the above technical solution, a liquid phase feed distributor is provided in the separation chamber. Preferably, the liquid phase feed distributor is arranged on the upper part of the selective hydrogenation catalyst bed and is an annular tube type or an annular belt type.

[0014] Furthermore, in the above technical solution, an aromatization catalyst is placed in the aromatization reaction zone to carry out aromatization and alkylation reactions on the low-carbon olefins in the light fraction gasoline, and simultaneously carry out a hydrodesulfurization reaction to reduce the olefin content while removing the easily removable sulfides in the light fraction gasoline.

[0015] Furthermore, in the above technical solution, the hydrodesulfurization reaction zone is a 2-n-layer tower plate structure, and a catalyst bed is arranged on each tower plate, wherein n is an integer greater than 2. The heavy fraction gasoline and the hydrogen feed are in reverse contact in the catalyst bed. A stripping chamber is arranged in the middle of the hydrodesulfurization reaction zone, which is a gas phase channel that runs through the hydrodesulfurization reaction zone, and the gas phase product after the hydrogenation reaction of each catalyst bed enters the gas phase channel under the action of stripping.

[0016] Furthermore, in the above technical solution, a hydrogen feed distributor is arranged under each catalyst bed, and the hydrogen feed distributor is an annular tube type or annular belt type structure.

[0017] Further, in the above technical solution, a gas-liquid guide unit may be provided between the hydrogen feed distributor and the bottom of each catalyst bed in the hydrodesulfurization reaction zone, and the gas guide unit includes: a guide plate, which is provided at the bottom of the catalyst bed, for receiving the liquid phase product after the hydrogenation reaction of the catalyst bed; a guide pipe, which is evenly arranged on the guide plate and guides the hydrogen feed upward to the catalyst bed, and a first cap is provided on the top of the guide pipe; an overflow weir, which is close to one side of the stripping chamber, for overflowing the liquid phase product on the guide plate to the next catalyst bed. Preferably, but not restrictively, the opening rate of the guide plate is generally 5% to 90%, the diameter of the guide hole is generally 3mm to 100mm, the height of the guide pipe is generally 10mm to 300mm, and the height difference between the overflow weir and the guide pipe is generally 5 to 250mm. Keep the cap just above the guide hole.

[0018] Furthermore, in the above technical solution, a liquid redistribution plate with an annular shape and uniformly provided through holes may be provided below the overflow weir. The liquid redistribution plate adopts a conventional structure in the art. A typical liquid redistribution plate includes: an overflow ring, which is arranged around the top of the through hole and is used to uniformly guide the liquid phase product to the next catalyst bed; a folded edge, which is arranged on the side away from the distillation chamber, and the upper edge of the folded edge is higher than the overflow ring. The height of the overflow ring is generally 1mm to 50mm.

[0019] Furthermore, in the above technical solution, the overflow ring includes: a serration portion, which is bent downward from the outer edge of the through hole toward the center; and a drainage groove, which is arranged on the serration portion and opened along the center of the serration portion.

[0020] Furthermore, in the above technical solution, a conical gas-liquid guide plate is provided in the stripping chamber, and the number and position of the gas-liquid guide plate match the catalyst bed. The conical surface of the gas-liquid guide plate is provided with air holes, and the top of the air holes is provided with a second cap; the gas phase product after the hydrogenation reaction rises from the air holes and converges into the distillation chamber, and part of the heavy component liquid phase product drips onto the gas-liquid guide plate and flows back to the reaction chamber.

[0021] Furthermore, in the above technical solution, the upper edge of the overflow weir may be 10 to 100 mm higher than the upper surface of the catalyst bed.

[0022] According to a second aspect of the present invention, the present invention also provides a method for hydrogenating full-fraction gasoline.

[0023] A full-fraction gasoline hydrogenation method comprises the following steps:

[0024] (1) After being heated, the full-fraction gasoline enters the separation chamber of the hydrogenation reactor, where the dienes in the gasoline are selectively hydrogenated under the action of a selective hydrogenation catalyst, and the full-fraction gasoline is fractionated into light fraction and heavy fraction gasoline;

[0025] (2) The light fraction gasoline obtained in step (1) enters the aromatization reaction zone of the hydrogenation reactor upwardly, and the low carbon olefins in the light fraction gasoline are subjected to aromatization and alkylation reactions under the action of the aromatization catalyst, and a hydrodesulfurization reaction is simultaneously carried out, and the gas phase stream finally flows out of the hydrogenation device upwardly;

[0026] (3) The heavy fraction obtained in step (1) flows downward into the hydrodesulfurization reaction zone, passes through multiple catalyst beds in the hydrodesulfurization reaction zone in sequence, and contacts and reacts with the hydrogen entering the catalyst beds upward; the gaseous product obtained by the reaction of each catalyst bed enters the stripping chamber, flows upward into the separation chamber in the stripping chamber, and flows upward out of the hydrogenation reactor together with the final gaseous stream obtained after the aromatization reaction in step (2); the liquid stream obtained by the reaction of each catalyst bed enters the next catalyst bed in sequence for reaction, and the final liquid stream flows downward out of the hydrogenation device.

[0027] Furthermore, in the above technical solution, a conical gas-liquid guide plate is provided in the stripping chamber of the hydrodesulfurization reaction zone. When the gas phase flow flows upward in the stripping chamber, part of the heavier components carried by it will fall back into the conical gas-liquid guide plate and be directed to each catalyst bed for re-reaction, while the light components continue to move upward through the gas-liquid guide plate pores and finally flow out from the top of the hydrogenation device.

[0028] Furthermore, in the above technical scheme, the discharge from the top of the hydrogenation unit is cooled and separated to obtain non-condensable gas and liquid. The non-condensable gas can be desulfurized to obtain hydrogen-rich gas. Part of the condensate is refluxed, and part of the condensate enters the stabilization tower together with the liquid phase flow flowing out from the bottom of the hydrogenation reactor. After the stabilization tower removes the non-condensable gas contained in it, a clean gasoline product is obtained from the bottom of the stabilization tower.

[0029] Furthermore, in the above technical solution, the hydrogen-rich gas obtained from the top of the hydrogenation reactor can be recycled.

[0030] Furthermore, in the above technical solution, the full-fraction gasoline includes one or a mixture of catalytic cracking gasoline, catalytic pyrolysis gasoline, coking gasoline and thermal cracking gasoline.

[0031] Further, in the above technical scheme, the reaction temperature of the aromatization reaction zone is 300°C to 500°C, preferably 300°C to 400°C; the reaction temperature of the hydrodesulfurization reaction zone is 200°C to 300°C; the operating pressure of the hydrogenation unit is 1.0MPa to 3.0MPa, preferably 1.5MPa to 2.8MPa, the hydrogen-to-oil volume ratio is 200 to 1000, and the liquid hourly volume space velocity is 0.5h -1 ~8.0h -1 .

[0032] Furthermore, in the above technical solution, the selective hydrogenation catalyst loaded in the separation section in step (1) is mainly used to selectively remove dienes from the whole fraction gasoline, so as to selectively hydrogenate the dienes to generate monoolefins, thereby preventing the dienes from polymerizing to generate high molecular weight compounds, covering the catalyst pores, causing catalyst deactivation, and reducing the catalyst life. The selective hydrogenation catalyst is generally based on alumina or silicon-containing alumina as a carrier, and a metal of group VIB and group VIII as an active component, such as one, two or more selected from W, Mo, Co, and Ni.

[0033] Furthermore, in the above technical solution, the aromatization catalyst in step (2) generally comprises an active component and a carrier, the carrier component comprises modified ZSM-5, ZSM-22 or a mixture of ZSM-5 and ZSM-22, and the active component is A combination of at least one metal from Group B and at least one metal from Group VIII, The Group B metal is generally La, and the Group VIII metal is generally Co and / or Ni.

[0034] Furthermore, in the above technical solution, the catalyst bed of the hydrodesulfurization reaction zone in step (3) is loaded with a hydrodesulfurization catalyst. The hydrodesulfurization catalyst generally comprises an active component and a carrier, wherein the carrier component comprises alumina, silica or a mixture of alumina and silica; the active component is one or more of Group VIB and Group VIII metals, wherein the Group VIB metal is generally Mo and / or W, and the Group VIII metal is generally Co and / or Ni.

[0035] Furthermore, in the above technical solution, the shape of the selective hydrogenation catalyst, aromatization catalyst and hydrodesulfurization catalyst can be any conventional existing catalyst shape, preferably a porous catalyst, a shaped catalyst and / or a honeycomb catalyst. The pore size of the porous catalyst is 1 to 50 mm, preferably 4 to 20 mm; the average particle diameter of the shaped catalyst is 2 to 50 mm, preferably 4 to 30 mm; the pore diameter or pore side length of the honeycomb catalyst is 1 to 50 mm, preferably 3 to 15 mm; the recommended void ratio of the catalyst bed is 15% to 85%, preferably 20% to 75%.

[0036] Compared with the prior art, the advantages of the present invention are:

[0037] 1. The present invention separates gasoline into light gasoline and heavy gasoline fractions by setting a separation chamber in a hydrogenation reactor according to the distribution characteristics of olefins and sulfur in FCC gasoline (olefin distribution increases with the decrease of the boiling point of the fraction; sulfur is mainly concentrated in the heavy gasoline fraction, and is mainly thiophene sulfides, and mercaptan sulfur is mainly concentrated in the light gasoline fraction). In the upper section of the hydrogenation reactor, under the action of an aromatization catalyst, the C4~C7 small molecule olefins in the light gasoline fraction undergo alkylation, aromatization and isomerization reactions to generate aromatics and cycloalkanes with high octane numbers, which greatly reduces the olefin content, and the octane number and gasoline yield of the final product are high. The heavy gasoline fraction separated is subjected to thiophene sulfide hydrodesulfurization reaction in the lower section of the hydrogenation reactor, so that each fraction is treated under appropriate conditions, and the process flow is simple and easy to operate.

[0038] 2. The temperature of the upper aromatization reaction zone of the present invention is relatively high, while the temperature of the lower hydrodesulfurization reaction zone is relatively low. The hydrodesulfurization process is a highly exothermic reaction. The gas phase products and hydrogen obtained by the reaction flow upward from the gas phase channel through the separation chamber into the upper aromatization olefin reduction catalyst bed layer, carrying a large amount of reaction heat, which can not only prevent the lower hydrodesulfurization reaction zone from rising too high in temperature, but also be used to heat the upper aromatization material, effectively utilizing the system heat.

[0039] 3. The hydrogen sulfide generated in the lower hydrodesulfurization reaction zone can immediately leave the hydrodesulfurization reaction zone from the stripping chamber, effectively preventing hydrogen sulfide from further combining with olefins to form mercaptans, preventing the mercaptan content in the heavy gasoline fraction from exceeding the standard, and eliminating the strong inhibitory effect of hydrogen sulfide on the hydrodesulfurization of thiophene sulfides. In addition, although the hydrogen sulfide generated in the lower catalyst reaction zone enters the upper catalytic reaction zone, due to the high reaction temperature of the upper layer, the reaction rate constant of hydrogen sulfide and olefin to form mercaptans is low. Even if mercaptans are generated, they will quickly re-crackle into hydrogen sulfide and olefins at high temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the principle flow chart of the present invention and a schematic diagram of the structure of the hydrogenation reactor.

[0041] Figure 2 Schematic diagrams of two structures of a liquid feed distributor and a hydrogen feed distributor according to one embodiment of the present invention.

[0042] Figure 3 It is a schematic diagram of a catalyst bed structure according to one embodiment of the present invention.

[0043] Figure 4 Schematic diagram of the structure of a liquid redistribution plate according to one embodiment of the present invention.

[0044] Figure 5 It is a schematic diagram of the structure of a gas-liquid guide plate according to one embodiment of the present invention.

[0045] Among them: 1-1-aromatization reaction zone; 1-2-separation chamber; 1-3-hydrodesulfurization reaction zone; 1-4-distillation chamber; 2-stabilization tower; 3-gasoline; 4-new hydrogen; 5-gas phase logistics; 6-liquid phase logistics; 7-condenser; 8-light gasoline fraction; 9-non-condensable gas; 10-clean gasoline product; 11-non-condensable gas at the top of the stabilization tower.

[0046] 101-feed pipe; 102-liquid phase distribution pipe; 103-eyelet; 104, 105-material distributor; 201-catalyst bed; 202-gas guide unit; 203-gas distributor; 204-gas distribution chamber; 205-gas-liquid redistribution plate; 206-guide hole; 207-guide trough; 208-overflow weir; 209-guide trough outer wall; 210-guide trough inner wall; 211-gas-liquid guide plate; 301, 303-eyelet; 302-overflow ring; 304-folded edge; 401, 501-cap cover; 402-air hole; 403-annular cofferdam; 502-guide pipe. DETAILED DESCRIPTION

[0047] like Figure 1 As shown, a full-fraction gasoline hydrogenation method of the present invention comprises: after the gasoline 3 is heated, it enters the separation chamber 1-2 of the hydrogenation device 1, and under the action of the selective hydrogenation catalyst, the diolefins in the gasoline are selectively hydrogenated, and the full-fraction gasoline is fractionated into light fractions and heavy fractions. The light fraction gasoline enters the aromatization reaction zone 1-1 upward, and under the action of the aromatization catalyst, the low-carbon olefins in the light fraction gasoline are subjected to aromatization and alkylation reactions, and a hydrodesulfurization reaction is simultaneously performed, and the final resulting stream flows out of the hydrogenation device 1 upward.

[0048] The heavy fraction gasoline enters the hydrodesulfurization reaction zone 1-3 downward, and enters multiple catalyst beds in the hydrodesulfurization reaction zone 1-3 downward in turn. Hydrogen enters from the bottom of each bed, and enters the hydrodesulfurization catalyst bed evenly under the action of the gas distribution chamber 204 and the gas distributor 203. Carried by hydrogen, the gaseous product hydrogen sulfide, small molecular hydrocarbons and part of the large molecular hydrocarbons are separated from the bed and enter the stripping chamber 1-4, and flow upward into the separation chamber 1-2 in the stripping chamber 1-4, and flow upward out of the hydrogenation device together with the gaseous product after the aromatization reaction. The final gaseous phase flow 5 flows out from the top of the hydrogenation device 1 and enters the condenser 7. Part of the condensate is refluxed, and part of it enters the stabilization tower 2 as the light gasoline fraction 8. The non-condensable gas 9 can be recycled to obtain hydrogen-rich gas after dehydrogenation. Part of the heavy components carried by hydrogen enter the stripping chamber 1-4, fall into the gas-liquid guide plate 211 under the action of gravity, and then re-enter the next catalyst bed through the guide groove 207 for reaction, and the final liquid flow flows downward into the separation chamber 3 at the bottom of the first catalytic distillation tower 1. The liquid phase flow obtained by the reaction of each catalyst bed in the hydrodesulfurization reaction zone 1-3 enters the next catalyst bed in turn for reaction, and the final liquid phase flow 6 flows downward out of the hydrogenation device 1 and enters the stabilization tower 2. After the stabilization tower 2 removes the non-condensable gas 11 contained in the stabilization tower top, a clean gasoline product 10 is obtained from the stabilization tower bottom.

[0049] Further, in the present invention, the liquid phase distributor 21 may be an annular tubular type ( Figure 2 Left) and annular belt type ( Figure 2 The gas distributor 203 of the present invention can also adopt the same structure as the liquid phase feed distributor 3,

[0050] Further, in the present invention, if Figure 4 As shown, a plurality of through holes 303 are evenly provided on the liquid redistribution plate 205, and an overflow ring 302 is arranged on the upper part of the through hole 303. The overflow ring is arranged around the top of the through hole 303 to evenly guide the liquid phase product to the next catalyst bed. The folded edge 304 is arranged on the side away from the distillation chamber, and the upper edge of the folded edge 304 is higher than the overflow ring 302.

[0051] Further, in the present invention ( Figure 5Left figure), the gas at the bottom of the guide plate 211 passes through the air hole 402 in the second air guide pipe 403, and the cap 401 can prevent the downward liquid from passing through the air hole 402. Preferably, but not restrictively, the gas-liquid guide plate 52 is conical, with a vertex angle greater than 60° and less than 180°, and generally greater than 90°, to increase the gas phase channel space. The opening rate of the gas-liquid guide plate 211 is 5% to 99%, the diameter of the air hole 402 can be 3mm to 100mm, and the height of the second air guide pipe 403 is 1mm to 30mm.

[0052] Further, in the present invention, the feedstock oil passes through the bed downwards through the overflow weir 208 and enters the liquid redistribution plate 205 under the guidance of the guide groove 207. Hydrogen is introduced from the gas guide pipe 502 ( Figure 5 The gas guide hole 206 in the right figure enters the catalyst bed upward, and a cap 501 is provided on the upper part of the guide pipe to prevent the raw oil in the bed from entering the gas guide pipe. Preferably, but not restrictively, the opening rate of the liquid redistribution plate is 5% to 90%, the diameter of the hole 503 is 3 mm to 100 mm, the height of the gas guide pipe 502 is 20 mm to 500 mm, and the height difference of the overflow weir 208 and the gas guide pipe 502 is -50 to -200 mm. It is sufficient to keep the cap 501 directly above the first gas guide pipe 502.

[0053] Example 1

[0054] The above-mentioned device and process of the present invention are used to carry out catalytic distillation treatment on the raw material catalytic cracking gasoline. The properties of the raw material catalytic cracking oil are shown in Table 1.

[0055] In the above technical solution, the height of the separation chamber arranged in the hydrogenation unit is 15% of the height of the hydrogenation unit, and the ratio of the height of the aromatization reaction zone to the height of the hydrodesulfurization reaction zone is 2:3.

[0056] The ratio of the height of the aromatization reaction zone to the height of the hydrodesulfurization reaction zone is 5:1 to 1:8, preferably 3:1 to 1:6.

[0057] After being heated, gasoline enters the separation chamber of the hydrogenation unit. Under the action of the selective diolefin removal catalyst SHT (trade name, produced by Sinopec Dalian Petrochemical Research Institute), the diolefins in the gasoline are selectively hydrogenated, and the full-fraction gasoline is fractionated into light fractions and heavy fractions. The light fraction gasoline enters the aromatization reaction zone upward, and under the action of the aromatization olefin reduction catalyst FDO-2 (trade name, produced by Sinopec Dalian Petrochemical Research Institute), the low-carbon olefins in the light fraction gasoline are aromatized and alkylated, and the hydrodesulfurization reaction is carried out at the same time. The final stream flows out of the hydrogenation unit upward.

[0058] There are 10 layers of trays in the hydrodesulfurization reaction zone, and each layer of tray is loaded with hydrodesulfurization catalyst ME-1 (trademark, produced by Sinopec Dalian Petrochemical Research Institute). The heavy fraction gasoline descends in the hydrodesulfurization reaction zone and enters multiple catalyst beds in turn, and hydrogen enters the hydrodesulfurization catalyst bed evenly from the bottom of each bed. Carried by hydrogen, the gaseous product hydrogen sulfide, small molecular hydrocarbons and some large molecular hydrocarbons separate from the bed and enter the stripping chamber, flow upward into the separation chamber in the stripping chamber, and flow upward out of the hydrogenation device together with the gaseous product after the aromatization reaction. The final gaseous phase flow flows out from the top of the hydrogenation device and enters the condenser. Part of the condensate is refluxed, and part enters the stabilization tower as a light gasoline fraction. After the non-condensable gas is desulfurized, hydrogen-rich gas can be obtained for recycling. The part of the heavy components carried by hydrogen enters the stripping chamber, and re-enters the next catalyst bed through the gas-liquid guide plate under the action of gravity for reaction. The final liquid flow flows downward into the separation chamber at the bottom of a catalytic distillation tower. The liquid phase flow obtained by the reaction of each catalyst bed in the hydrodesulfurization reaction zone enters the next catalyst bed in turn for reaction, and the final liquid phase flow flows downward out of the hydrogenation device and enters the stabilization tower. After the stabilization tower removes the non-condensable gas contained in the stabilization tower top, the clean gasoline product is obtained from the stabilization tower bottom.

[0059] The reaction process conditions are shown in Table 2, and the properties of the clean gasoline product are shown in Table 3.

[0060] Example 2

[0061] The difference between this embodiment and embodiment 1 is that the height of the separation chamber set in the hydrogenation unit is 10% of the height of the hydrogenation unit, and the ratio of the height of the aromatization reaction zone to the height of the hydrodesulfurization reaction zone is 1:3. 20 layers of trays are set in the hydrodesulfurization reaction zone, and each layer of tray is loaded with hydrodesulfurization catalyst ME-1. The reaction process conditions are shown in Table 2, and the properties of the clean gasoline product are shown in Table 3. The remaining conditions are the same as those in embodiment 1.

[0062] Example 3

[0063] The difference between this embodiment and embodiment 1 is that the height of the separation chamber set in the hydrogenation unit is 20% of the height of the hydrogenation unit, and the ratio of the height of the aromatization reaction zone to the height of the hydrodesulfurization reaction zone is 2:1. The reaction process conditions are shown in Table 2, and the properties of the clean gasoline product are shown in Table 3. The remaining conditions are the same as those in embodiment 1.

[0064] Embodiment 4-5

[0065] The same as Example 1, the only difference is that the reaction conditions are changed. The specific reaction process conditions are shown in Table 2, and the properties of the clean gasoline product are shown in Table 3.

[0066] Comparative Example 1

[0067] The hydrodesulfurization reaction zone in the hydrogenation unit adopts a conventional fixed bed style and is loaded with hydrodesulfurization catalyst ME-1. The other conditions are the same as those in Example 1. The properties of the clean gasoline product are shown in Table 3.

[0068] Table 1 Main properties of catalytic cracking gasoline

[0069]

[0070] The reaction temperature of the aromatization reaction zone is 300°C to 500°C, preferably 300°C to 400°C; the reaction temperature of the hydrodesulfurization reaction zone is 200°C to 300°C; the operating pressure of the hydrogenation unit is 1.0MPa to 3.0MPa, preferably 1.5MPa to 2.8MPa, the hydrogen-to-oil volume ratio is 200 to 1000, and the liquid hourly volume space velocity is 0.5h -1 ~8.0h -1 .

[0071] Table 2 Example process conditions

[0072]

[0073] Table 3 Clean gasoline product properties

[0074]

[0075] From the results in Table 3, it can be seen that the method of the present invention can produce clean gasoline that meets the Beijing 6B motor gasoline standard, with an olefin volume fraction of no more than 12%, a sulfur mass fraction of less than 10ppm, an antiknock index loss of less than 0.9, and a low mercaptan content. However, the total sulfur content of Comparative Example 1 exceeds 86ppm, the mercaptan content exceeds the standard, and the antiknock index loss is 1.3, which cannot meet the Beijing 6B motor gasoline standard.

Claims

1. A full-fraction gasoline hydrogenation reactor, characterized in that: From top to bottom, it includes: aromatization reaction zone, separation chamber and hydrodesulfurization reaction zone; A selective hydrogenation catalyst is arranged in the separation chamber, and the separation chamber is used to selectively hydrogenate the dienes in the full-fraction gasoline feedstock and separate it into a light fraction and a heavy fraction, wherein the light fraction enters the aromatization reaction zone upward, and the heavy fraction enters the hydrodesulfurization reaction zone downward; The aromatization reaction zone is used to carry out aromatization and alkylation reactions on the low-carbon olefins in the light fraction, and simultaneously carry out hydrodesulfurization reactions; A stripping chamber is provided in the middle of the hydrodesulfurization reaction zone, which is a gas phase channel that runs through the hydrodesulfurization reaction zone, and the gas phase product after the hydrogenation reaction of each catalyst bed enters the gas phase channel under the action of stripping; the hydrodesulfurization reaction zone receives the heavy fraction descending from the separation chamber as a liquid phase feed, and the liquid phase feed flows from top to bottom through each catalyst bed provided in the hydrodesulfurization reaction zone; the preheated hydrogen enters each catalyst bed uniformly from the bottom of each catalyst bed from bottom to top; the liquid phase feed and hydrogen undergo a hydrodesulfurization reaction on the hydrodesulfurization catalyst; the hydrogen sulfide generated by the hydrodesulfurization and the unreacted gas phase feed leave the hydrodesulfurization reaction zone from the stripping chamber through an independent gas phase channel, and the liquid product obtained by the hydrodesulfurization is discharged from the hydrodesulfurization reaction zone; The hydrodesulfurization reaction zone is a 2-n-layer tower plate structure, each tower plate is provided with a catalyst bed, wherein n is an integer greater than 2; a hydrogen feed distributor is provided at the bottom of each catalyst bed; the hydrogen feed distributor is an annular tube type or annular belt type structure; A gas-liquid guide unit is provided between the hydrogen feed distributor and the bottom of each catalyst bed in the hydrodesulfurization reaction zone, and the gas-liquid guide unit comprises: a guide plate, which is provided at the bottom of the catalyst bed and is used to receive the liquid phase product after the hydrogenation reaction of the catalyst bed; a guide pipe, which is evenly arranged on the guide plate and guides the hydrogen feed upward to the catalyst bed, and a first cap is provided on the top of the guide pipe; an overflow weir, which is close to one side of the stripping chamber and is used to overflow the liquid phase product on the guide plate to the next catalyst bed; The stripping chamber is provided with a conical gas-liquid guide plate, and the number and position of the gas-liquid guide plate are matched with the catalyst bed.

2. The hydrogenation reactor according to claim 1, characterized in that The height of the separation chamber is 10% to 30% of the height of the hydrogenation reactor, and the ratio of the height of the aromatization reaction zone to the height of the hydrodesulfurization reaction zone is 5:1 to 1:

8.

3. The hydrogenation reactor according to claim 1, characterized in that: Fillers or trays are placed in the separation chamber, or a selective hydrogenation catalyst is arranged.

4. The hydrogenation reactor according to claim 1, characterized in that A liquid phase feed distributor is arranged in the separation chamber.

5. The hydrogenation reactor according to claim 1, characterized in that: The aromatization reaction zone is provided with an aromatization catalyst for carrying out aromatization and alkylation reactions on low-carbon olefins in light fraction gasoline.

6. The hydrogenation reactor according to claim 1, characterized in that: An annular liquid redistribution plate with evenly-spaced through holes is provided below the overflow weir.

7. The hydrogenation reactor according to claim 6, characterized in that The liquid redistribution plate comprises: an overflow ring arranged around the top of the through hole for uniformly guiding the liquid phase product to the next catalyst bed; a folded edge arranged on the side away from the stripping chamber, the upper edge of the folded edge being higher than the overflow ring.

8. The hydrogenation reactor according to claim 7, characterized in that The overflow ring comprises: a sawtooth portion, which is bent downward from the outer edge of the through hole toward the center; and a drainage groove, which is arranged on the sawtooth portion and opened along the center of the sawtooth portion.

9. A full-fraction gasoline hydrogenation method, characterized in that: The hydrogenation reactor according to any one of claims 1 to 8 is used, and the method comprises the following steps: (1) After being heated, the whole-fraction gasoline feedstock enters the separation chamber of the hydrogenation reactor, where the dienes in the whole-fraction gasoline feedstock are selectively hydrogenated under the action of a selective hydrogenation catalyst, and the whole-fraction gasoline feedstock is fractionated into a light fraction and a heavy fraction; (2) The light fraction obtained in step (1) flows upward into the aromatization reaction zone of the hydrogenation reactor, and under the action of the aromatization catalyst, the low-carbon olefins in the light fraction undergo aromatization and alkylation reactions, and a hydrodesulfurization reaction is simultaneously performed, and the resulting gas phase stream flows upward out of the hydrogenation reactor; (3) The heavy fraction obtained in step (1) flows downward into the hydrodesulfurization reaction zone, passes through multiple catalyst beds in the hydrodesulfurization reaction zone in sequence, and contacts and reacts with the hydrogen entering the catalyst beds upward; the gaseous product obtained by the reaction of each catalyst bed enters the stripping chamber, flows upward into the separation chamber in the stripping chamber, and flows upward out of the hydrogenation reactor together with the final gaseous stream obtained after the aromatization reaction in step (2); the liquid stream obtained by the reaction of each catalyst bed enters the next catalyst bed in sequence for reaction, and the final liquid stream flows downward out of the hydrogenation reactor.

10. The hydrogenation method according to claim 9, characterized in that: The discharge from the top of the hydrogenation reactor is cooled and separated to obtain non-condensable gas and condensate. The non-condensable gas is desulfurized to obtain hydrogen-rich gas. Part of the condensate is refluxed, and part of the condensate enters the stabilization tower together with the liquid phase flow flowing out from the bottom of the hydrogenation reactor. After the stabilization tower removes the non-condensable gas contained in it, a clean gasoline product is obtained from the bottom of the stabilization tower.

11. The hydrogenation method according to claim 9, characterized in that: The full-fraction gasoline raw material includes one or a mixture of catalytic cracking gasoline, catalytic pyrolysis gasoline and thermal cracking gasoline.

12. The hydrogenation method according to claim 9, characterized in that: The reaction temperature of the aromatization reaction zone is 300°C to 500°C; the reaction temperature of the hydrodesulfurization reaction zone is 200°C to 300°C; the operating pressure of the hydrogenation reactor is 1.0MPa to 3.0MPa, the hydrogen-oil volume ratio is 200 to 1000, and the liquid hourly volume space velocity is 0.5h -1 ~8.0h -1 .

Images