A gas phase pyrolysis coal tar ring-enhancing modification and graded hydrogenation process and integrated reactor

Abstract

The present invention belongs to the field of coal tar processing, and relates to a gas-phase pyrolysis coal tar ring-increasing modification graded hydrogenation process and an integrated reactor, wherein the integrated reactor comprises a reaction distillation tower, wherein the reaction distillation tower is internally divided into a distillation section and a ring-increasing modification section from top to bottom; the ring-increasing modification section is used to perform ring-increasing modification on the gas-phase pyrolysis coal tar; and the distillation section is used to perform graded hydrogenation on the gas-phase pyrolysis coal tar after the ring-increasing modification. The integrated reactor of the present invention uses gas-phase pyrolysis coal tar as raw material, and realizes efficient utilization of gas-phase pyrolysis tar through ring-increasing, hydrogenation and distillation separation, thereby saving energy and reducing processing costs.

Description

Technical Field

[0001] The invention belongs to the field of coal tar processing and relates to a gas phase pyrolysis coal tar ring-increasing modification graded hydrogenation process and an integrated reactor. Background Art

[0002] my country is a major producer of coke, accounting for about 40% of the world's coke production. As a byproduct of coke production, coal tar processing is increasingly valued. At present, there are three main ways to efficiently utilize coal tar: first, use specific technologies to extract specific substances and achieve refined processes; second, use the recombinant fractions in coal tar as raw materials to produce carbon black, needle coke, asphalt and other substances; third, use hydrogen as a reactant to achieve catalytic hydrogenation of coal tar to produce liquid fuel.

[0003] In addition, with the rapid development of the aerospace industry in recent years, the demand for high-density fuels has increased, and higher requirements have been placed on their performance. After decades of rapid development, traditional petroleum-based fuels have gradually entered a stable and mature stage. While meeting current needs, achieving high volumetric energy density and excellent high-temperature stability has gradually been limited, and it is difficult to meet the needs well. Coal tar is a product of high-temperature dry distillation of coal. It is a complex compound of hydrocarbons with high aromaticity. Most of them are polycyclic and condensed ring compounds with or without side chains, and heterocyclic compounds containing oxygen, sulfur, and nitrogen, and contain a small amount of aliphatic hydrocarbons, cycloalkanes, and unsaturated hydrocarbons. Its unique component characteristics make it very suitable for the production of high-density fuels, but due to the large difference in the number of rings of its internal components, a ring-increasing reaction is required to make the high-density fuel produced have better properties.

[0004] With the continuous consumption of fossil energy, it is necessary to find a substitute for petroleum to produce fuel oil. Therefore, the processing and utilization of coal tar has been developing continuously in recent years. However, the existing main processing processes do not directly use gas phase pyrolysis coal tar as raw material. They all use liquid phase coal tar as raw material and then heat it to a specified temperature, resulting in a huge waste of energy. In addition, the existing ring addition reaction, hydrogenation treatment, and distillation separation are all carried out in different equipment, resulting in large equipment and investment, which greatly increases the processing cost. Summary of the invention

[0005] In view of the technical problem that the existing coal tar processing uses liquid coal tar as raw material, resulting in huge energy waste and a significant increase in processing costs, the present invention provides a gas-phase pyrolysis coal tar ring-addition modification graded hydrogenation process and an integrated reactor.

[0006] The integrated reactor of the present invention uses gas-phase pyrolysis coal tar as raw material, and realizes efficient utilization of gas-phase pyrolysis tar through ring addition, hydrogenation and distillation separation, thereby saving energy and reducing processing costs.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] An integrated reactor for realizing the gas phase pyrolysis coal tar ring-increasing modification and staged hydrogenation process, including a reaction distillation tower,

[0009] The interior of the reaction distillation tower is divided into a distillation section and a ring-increasing modification section from top to bottom; the ring-increasing modification section is used to perform ring-increasing modification on gas-phase pyrolysis coal tar; the distillation section is used to perform graded hydrogenation on the gas-phase pyrolysis coal tar after ring-increasing modification;

[0010] In the ring-increasing and modifying section, a pyrolysis gas feed port, a bottom product discharge port and a gas phase reflux port are respectively arranged at the bottom of the reaction distillation tower, and a ring-increasing and modifying agent inlet is arranged on the tower side of the reaction distillation tower;

[0011] In the distillation section, a primary reaction section and a secondary reaction section are sequentially arranged in the reaction distillation tower from bottom to top; H 2 Inlet and side product outlet, H 2 The inlet is located between the primary reaction section and the secondary reaction section, the side product outlet is located at the upper part of the secondary reaction section, and the top of the reaction distillation tower is respectively provided with a tower top tail gas outlet and a liquid phase reflux inlet.

[0012] It is further defined that a gas phase distribution device is also provided in the ring-increasing and modifying section of the reactive distillation tower; the gas phase distribution device is located between the gas phase reflux inlet and the ring-increasing and modifying agent inlet, and is connected to the pyrolysis gas feed inlet.

[0013] It is further defined that the integrated reactor further comprises a liquid redistributor and a liquid collector respectively arranged between the primary reaction section and the secondary reaction section; the liquid redistributor is located below the liquid collector, and the liquid redistributor is located below the H 2 Above the entrance.

[0014] It is further defined that the integrated reactor also includes a liquid redistributor and a liquid collector arranged above the secondary reaction section; the liquid redistributor is close to the secondary reaction section.

[0015] It is further defined that the integrated reactor also includes a tower plate arranged between the primary reaction section and the secondary reaction section and on the upper part of the secondary reaction section.

[0016] It is further defined that the number of tower plates between the primary reaction section and the secondary reaction section is 4 to 8; the number of tower plates on the upper part of the secondary reaction section is 12 to 18.

[0017] It is further defined that the primary reaction section includes a packing support plate, a first catalyst layer and a packing pressure plate stacked in sequence from bottom to top; the secondary reaction section includes a packing support plate, a second catalyst layer and a packing pressure plate connected in sequence from bottom to top; the first catalyst layer is Ni / Al 2 O 3 Catalyst layer; the second catalyst layer is Ni-Mo / Al 2 O 3 Catalyst layer.

[0018] The gas phase pyrolysis coal tar ring-increasing modification and graded hydrogenation process based on the integrated reactor is characterized in that the gas phase pyrolysis coal tar ring-increasing modification and graded hydrogenation process comprises the following steps:

[0019] S1, ring-addition modification

[0020] The gas phase pyrolysis coal tar is introduced into the reaction distillation tower from the pyrolysis gas feed port, and the ring-increasing modifier is introduced into the reaction distillation tower through the ring-increasing modifier inlet; under the action of the ring-increasing reaction catalyst, the gas phase pyrolysis coal tar and the ring-increasing modifier undergo a ring-increasing modification reaction to obtain a heavy component and a light component;

[0021] S2, staged hydrogenation

[0022] The heavy components of step S1 are extracted from the bottom product outlet of the tower and heated in a kettle reboiler to obtain heavy tar and gas phase, and the gas phase is refluxed to the ring-increasing modification section through the gas phase reflux inlet;

[0023] The light components in step S1 are hydrogenated by low-temperature hydrogen dissolution in the primary reaction section and then react with H 2 The high-temperature hydrogen coming in from the inlet is mixed, and then goes upward through the secondary reaction section for high-temperature hydrogenation to obtain a reaction product;

[0024] S3. Separation

[0025] The reaction product of step S2 is separated to obtain a diesel fraction and a residual component; the diesel fraction is extracted from the side product outlet; the residual component is discharged from the tail gas outlet at the top of the tower and then cooled and separated to obtain a liquid phase and tail gas; a portion of the liquid phase is refluxed to the distillation section through the liquid phase reflux inlet, another portion of the liquid phase is collected, a portion of the tail gas is discharged, and a portion of the tail gas is circulated as high-temperature hydrogen.

[0026] It is further defined that in the ring-increasing modification of step S1, the ring-increasing modifier is cyclopentadiene, and the ring-increasing reaction catalyst is AlCl 3; The coal tar content in the gas-phase pyrolysis coal tar is 5wt%~10wt%; the feed flow rate of the gas-phase pyrolysis coal tar is 2L / h~6L / h, the mass ratio of coal tar, ring-enhancing modifier and ring-enhancing reaction catalyst in the gas-phase pyrolysis coal tar is 1:2~3:10, the pressure is 1MPa~2MPa; the temperature is 100℃~120℃.

[0027] It is further defined that in step S2, the volume ratio of high-temperature hydrogen and gas-phase pyrolysis coal tar is 1:1000-1300; the high-temperature hydrogen consists of two parts: fresh hydrogen and circulating hydrogen, the volume of circulating hydrogen accounts for 60%-80% of the total volume of high-temperature hydrogen, and the temperature of high-temperature hydrogen is 400°C-420°C; the circulating hydrogen comes from tail gas.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] 1. The integrated reactor of the present invention uses gas-phase pyrolysis coal tar as raw material, and separates through ring addition, hydrogenation and distillation. There is no need to condense the coal tar produced by high-temperature dry distillation of coke into a liquid phase, thereby achieving efficient utilization of gas-phase pyrolysis tar, saving energy, reducing processing costs, and achieving the purpose of energy saving and cost reduction.

[0030] 2. The integrated reactor provided by the present invention enables gas-phase pyrolysis coal tar to remain in the gas phase at a relatively low temperature, which not only realizes the ring-increasing of gas-phase tar, but also realizes preliminary hydrogenation under low-pressure conditions, completes the deep processing of gas-phase pyrolysis coal tar, and maximizes the use of resources.

[0031] 3. In the present invention, the ring-addition reaction is carried out in the kettle of the reaction distillation tower, and the hydrogenation reaction is carried out in the upper part of the kettle of the reaction distillation tower. Distillation separation is carried out simultaneously in one reaction distillation tower to achieve the coupling of distillation, hydrogenation and ring-addition modification processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a process flow chart of the integrated gas phase pyrolysis ring-adding modification and graded hydrogenation of the present invention;

[0033] Figure 2 It is a schematic diagram of the structure of the integrated reactor for gas phase pyrolysis ring-addition modification and graded hydrogenation in the present invention;

[0034] Figure 3 It is a partial ring-addition modification reaction formula;

[0035] Figure 1 Description of the mark in:

[0036] a-reaction distillation tower, b-kettle reboiler, c-gas-liquid separation tank, d-tower top condenser, e-hydrogen centrifugal fan, f-hydrogen heater, g-hydrogen temporary storage tank, h-pyrolysis gas centrifugal fan, i-cyclopentadiene feed pump;

[0037] Figure 2 Description of the mark in:

[0038] 1-tower wall, 2-gas phase distributor, 3-pyrolysis gas feed inlet, 4-heavy tar outlet, 5-tower bottom gas phase reflux inlet, 6-modifier inlet, 7-packing support plate, 8-first catalyst packing, 9-packing pressure plate, 10-liquid phase distributor, 11-liquid phase collector, 12-second catalyst packing, 13-light tar outlet, 14-tower top liquid phase reflux inlet, 15-tower top tail gas outlet, 16-distillation tower plate, 17-hydrogen inlet. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments, but the protection scope of the present invention is not limited to these embodiments.

[0040] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0041] Technologies, methods, and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0042] It should also be understood that the specific embodiments described above are only used to explain the present invention, and the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, which should be covered by the protection scope of the present invention / invention.

[0043] Example 1

[0044] See also Figure 1 and Figure 2 This embodiment provides an integrated reactor for realizing the gas phase pyrolysis coal tar ring-enhancing modification and graded hydrogenation process.

[0045] In this embodiment, the integrated reactor includes a reaction distillation tower a,

[0046] The interior of the reaction distillation tower a is divided into a distillation section and a ring-adding modification section from top to bottom; the ring-adding modification section is used to perform ring-adding modification on gas-phase pyrolysis coal tar; and the distillation section is used to perform graded hydrogenation on the gas-phase pyrolysis coal tar after ring-adding modification.

[0047] In the ring-adding modification section of this embodiment, a pyrolysis gas feed port 3, a bottom product discharge port 4 and a gas phase reflux port 5 are respectively arranged at the bottom of the reaction distillation tower a, and a ring-adding modifier inlet 6 is arranged on the tower side of the reaction distillation tower a.

[0048] Preferably, the ring-addition modifier inlet 6 is used to introduce the ring-addition reaction catalyst and the ring-addition modifier into the ring-addition modification section in the reaction distillation tower a.

[0049] In the distillation section of this embodiment, the first reaction section 8 and the second reaction section 12 are arranged in the reaction distillation tower a from bottom to top; the tower sides of the reaction distillation tower a are respectively provided with H 2 Inlet 17 and side product outlet 13, H 2 The inlet 17 is located between the primary reaction section 8 and the secondary reaction section 12, the side product outlet 13 is located at the upper part of the secondary reaction section 12, and the top of the reaction distillation tower a is respectively provided with a top tail gas outlet 15 and a liquid reflux inlet 14.

[0050] A gas phase distribution device 2 is also provided in the ring-adding and modifying section of the reaction distillation tower a; the gas phase distribution device 2 is located between the gas phase reflux inlet 5 and the ring-adding and modifying agent inlet 6, and is connected to the pyrolysis gas feed inlet 3.

[0051] The integrated reactor further comprises a liquid redistributor 10 and a liquid collector 11 respectively arranged between the primary reaction section 8 and the secondary reaction section 12; the liquid redistributor 10 is located below the liquid collector 11, and the liquid redistributor 10 is located between the H 2 Above entrance 17.

[0052] The integrated reactor further includes a liquid redistributor 10 and a liquid collector 11 which are arranged above the secondary reaction section 12 ; the liquid redistributor 10 is close to the secondary reaction section 12 .

[0053] The integrated reactor further includes a tower plate 16 disposed between the primary reaction section 8 and the secondary reaction section 12 and at the upper portion of the secondary reaction section 12 .

[0054] Preferably, the number of the tower plates 16 between the primary reaction section 8 and the secondary reaction section 12 is 4 to 8; the number of the tower plates 16 on the upper part of the secondary reaction section 12 is 12 to 18.

[0055] In this embodiment, the primary reaction section 8 includes a packing support plate 7, a first catalyst layer and a packing pressure plate 9 stacked in sequence from bottom to top; the secondary reaction section 12 includes a packing support plate 7, a second catalyst layer and a packing pressure plate 9 connected in sequence from bottom to top; the first catalyst layer is Ni / Al 2 O 3 Catalyst layer; the second catalyst layer is Ni-Mo / Al 2 O 3 Catalyst layer.

[0056] Preferably, Ni / Al 2 O 3 In the catalyst, the total mass of Ni and Al accounts for Ni / Al 2 O3 20% of the total mass of the catalyst; Ni-Mo / Al 2 O 3 In the catalyst, the mass ratio of Ni to Mo is 1:4, and the total mass of Ni, Mo and Al accounts for Ni-Mo / Al 2 O 3 The total mass of catalyst is 20%.

[0057] In Example 1, the specific structural dimensions of the above equipment are shown in Table 1 below.

[0058] Table 1 Structural parameters of integrated reactor

[0059]

[0060] In this embodiment, the above-mentioned integrated reactor is used to realize the ring-increasing, modification and graded hydrogenation of gas-phase pyrolysis coal tar.

[0061] In this embodiment, the gas phase pyrolysis coal tar ring-increasing modification and graded hydrogenation process comprises the following steps:

[0062] S1, ring-addition modification

[0063] The gas phase pyrolysis coal tar is introduced into the reaction distillation tower a from the pyrolysis gas feed port 3, and the ring-increasing modifier is introduced into the reaction distillation tower a through the ring-increasing modifier inlet 6; under the action of the ring-increasing reaction catalyst, the gas phase pyrolysis coal tar and the ring-increasing modifier undergo a ring-increasing modification reaction to obtain a heavy component and a light component;

[0064] See also Figure 3 These are the reaction equations for the modification of some components in gas phase pyrolysis coal tar with the ring-increasing modifier under the action of a catalyst. These reaction equations show that the reaction of components in gas phase pyrolysis coal tar with the ring-increasing modifier can generate heavy oil.

[0065] In the ring-addition modification of step S1, the ring-addition modifier is cyclopentadiene, and the ring-addition reaction catalyst is AlCl 3 ; The coal tar content in the gas-phase pyrolysis coal tar is 5wt%~10wt%; the feed flow rate of the gas-phase pyrolysis coal tar is 2L / h~6L / h, the mass ratio of coal tar, ring-enhancing modifier and ring-enhancing reaction catalyst in the gas-phase pyrolysis coal tar is 1:2~3:10, the pressure is 1MPa~2MPa; the temperature is 100℃~120℃.

[0066] S2, staged hydrogenation

[0067] The heavy components of step S1 are extracted from the bottom product outlet 4 and heated in the kettle reboiler b to obtain heavy tar and gas phase, and the gas phase is refluxed to the ring-increasing modification section through the gas phase reflux inlet 5;

[0068] The light components in step S1 are hydrogenated by low-temperature hydrogen dissolution in the primary reaction section 8 and then react with H 2 The high-temperature hydrogen gas entering from the inlet 17 is mixed and then passes upward through the secondary reaction section 12 for high-temperature hydrogenation to obtain a reaction product;

[0069] In step S2, the volume ratio of high-temperature hydrogen and gas-phase pyrolysis coal tar is 1:1000-1300; the high-temperature hydrogen consists of fresh hydrogen and circulating hydrogen, the volume of circulating hydrogen accounts for 60%-80% of the total volume of high-temperature hydrogen, and the temperature of high-temperature hydrogen is 400°C-420°C; the circulating hydrogen comes from tail gas.

[0070] S3. Separation

[0071] The reaction product of step S2 is separated to obtain a diesel fraction and a residual component; the diesel fraction is extracted from the side product outlet 13; the residual component is discharged from the top tail gas outlet 15 and then cooled and separated to obtain a liquid phase and tail gas; a portion of the liquid phase is refluxed to the distillation section through the liquid phase reflux inlet 14, another portion of the liquid phase is collected, a portion of the tail gas is discharged, and a portion of the tail gas is circulated as high-temperature hydrogen.

[0072] See also Figure 2 Preferably, a pyrolysis gas feed pipeline is externally connected to the pyrolysis gas feed port 3, and a pyrolysis gas centrifugal fan h is arranged on the pyrolysis gas feed pipeline; a cyclopentadiene feed pipeline is externally connected to the ring-increasing modifier inlet 6, and a cyclopentadiene feed pump i is arranged on the cyclopentadiene feed pipeline.

[0073] Preferably, an external kettle reboiler b is connected to the bottom of the reaction distillation tower a (ring-adding and modification section), a kettle reboiler inlet is arranged at the bottom of the kettle reboiler b and is connected to the bottom product discharge port 4, a gas phase outlet is arranged at the top of the kettle reboiler b and is connected to the gas phase reflux inlet 5, a heavy tar outlet is arranged on the side of the kettle reboiler b, and the collected heavy tar is transported to the product tank or the next process.

[0074] Preferably, H 2 The inlet 17 is connected to a hydrogen temporary storage tank g, and the hydrogen temporary storage tank g and H 2 A hydrogen centrifugal fan e and a hydrogen heater f are arranged in sequence between the inlet 17. The hydrogen heater f is close to the H 2 Inlet 17. Through the hydrogen storage tank g, hydrogen centrifugal fan e and hydrogen heater f, ensure H 2 Stable delivery,

[0075] Preferably, a gas-liquid separation tank c and a tower top condenser d are externally connected to the tower top tail gas outlet 15, and the tower top condenser d is close to the tower top tail gas outlet 15. Separation inlets are respectively arranged on the gas-liquid separation tank c and connected to the tower top condenser d. A tail gas outlet is also arranged on the gas-liquid separation tank c, and one tail gas outlet is sent to the outside of the boundary, and the other is connected to the hydrogen temporary storage tank g, so that the tail gas is recycled; a liquid phase outlet is also arranged on the gas-liquid separation tank c, and gasoline is collected at the liquid phase outlet, a part of which is transported to the product tank or the next process, and the other part is refluxed to the distillation section of the reaction distillation tower a through the liquid phase reflux inlet 14.

[0076] Specifically, gas phase pyrolysis coal tar is also called pyrolysis gas. The pyrolysis gas contains 5wt% to 10wt% of coal tar. The pyrolysis gas is transported to the reactor of the reaction distillation tower a by the pyrolysis gas centrifugal fan h, and is evenly dispersed by the gas phase distribution device 2. The ring-increasing modifier (cyclopentadiene) and the ring-increasing reaction catalyst are mixed according to the mass ratio and fed from the ring-increasing modifier inlet 6 through the cyclopentadiene feed pump i. The ring-increasing modification reaction is carried out in the reactor of the reaction distillation tower a. The ring-increasing product is discharged from the tower bottom product outlet 4, and is heated by the kettle reboiler b set in the tower reactor to separate the modifier and reflux to the reaction distillation tower a from the gas phase reflux inlet 5, and the heavy tar product is collected from the kettle reboiler b.

[0077] The unreintegrated light components in the reactor of the reaction distillation tower a rise to the reaction distillation section; the rising light components are first hydrogenated with low-temperature dissolved hydrogen in the primary reaction section, and then react with the high-temperature H 2 The feeds are mixed and subjected to high-temperature hydrogenation in the secondary reaction section; the secondary hydrogenation product is distilled and purified in the upper distillation section, and the light product is collected from the side product outlet 13 in the upper middle part of the reaction section, and the remaining components are discharged from the tail gas outlet 15 at the top of the tower, cooled by the top condenser d, and enter the gas-liquid separation tank c for separation, and the liquid phase refluxes back to the top of the tower from the liquid phase reflux inlet 14, and part of the tail gas is discharged, and part enters the hydrogen temporary storage tank g.

[0078] Preferably, this embodiment adopts the above-mentioned equipment to carry out ring-increasing modification and graded hydrogenation, the selected gas-phase pyrolysis coal tar has a coal tar ratio of 5wt%, the mass of the ring-increasing modifier cyclopentadiene is twice the mass of the coal tar in the gas-phase pyrolysis coal tar, the mass ratio of coal tar to the ring-increasing reaction catalyst in the gas-phase pyrolysis coal tar is 1:10, the volume ratio of high-temperature hydrogen and gas-phase pyrolysis coal tar, that is, the hydrogen-to-oil ratio is 1:1100, and the pressure used for high-temperature hydrogenation is 1MPa; the specific process parameters are listed in Table 2 below.

[0079] Table 2 Process parameters

[0080]

[0081] Preferably, in this embodiment 1, the composition of the pyrolysis gas is as shown in Table 3.

[0082] Table 3 Pyrolysis gas composition

[0083]

[0084]

[0085] The pyrolysis gas is subjected to corresponding ring-addition modification and hydrogenation reaction under the process parameter conditions listed in Table 1 and Table 2, and finally gasoline and tail gas are discharged from the top of the tower, diesel with a distillation range of 180°C to 280°C is discharged from the side line, and heavy tar with a boiling point above 280°C is extracted from the bottom side of the tower.

[0086] The relevant properties and standards of gasoline and diesel products are listed in Tables 4 and 5 below, and the composition of tail gas and heavy tar is listed in Tables 6 and 7.

[0087] Table 4 National gasoline standard (VIA) and properties of this product

[0088]

[0089]

[0090] Table 5 Diesel national standard (VIA) and properties of this product

[0091]

[0092]

[0093] Table 6 Composition of heavy tar

[0094] Compound Type % Straight chain compounds 15.17 Monocyclic compounds 0.03 Bicyclic compounds 11.52 Tricyclic and above compounds 73.28

[0095] Table 7 Tail gas composition

[0096] <![CDATA[H 2 ]]> 65.13 CO 11.63 <![CDATA[CO 2 ]]> 5.39 <![CDATA[C 1 ~C 4 ]]> 14.21 <![CDATA[N 2 ]]> 2.17 <![CDATA[NH 3 ]]> 1.24 <![CDATA[H 2 S]]> 0.15 <![CDATA[H 2 The]]> 0.08

[0097] Example 2

[0098] The difference from Example 1 is that the hydrogen-to-oil ratio is 1120:1.

[0099] Example 3

[0100] The difference from Example 1 is that the hydrogen-to-oil ratio is 1140:1.

[0101] Example 4

[0102] The difference from Example 1 is that the hydrogen-to-oil ratio selected is 1160:1.

[0103] Example 5

[0104] The difference from Example 1 is that the hydrogen-to-oil ratio selected is 1180:1.

[0105] Example 6

[0106] The difference from Example 1 is that the hydrogen-to-oil ratio is 1200:1.

[0107] Example 7

[0108] The difference from Example 1 is that the hydrogen-to-oil ratio is 1220:1.

[0109] Example 8

[0110] The difference from Example 1 is that the hydrogen-to-oil ratio selected is 1240:1.

[0111] Example 9

[0112] The difference from Example 1 is that the hydrogen-to-oil ratio is 1260:1.

[0113] Example 10

[0114] The difference from Example 1 is that the hydrogen-to-oil ratio is 1280:1.

[0115] Embodiment 11

[0116] The difference from Example 1 is that the hydrogen-to-oil ratio is 1300:1. The test results of Examples 1-11 with changed pressure are compared in Table 8 below.

[0117] Table 8 Test results at different hydrogen-to-oil ratios

[0118]

[0119]

[0120] It can be seen from Table 8 that as the hydrogen-to-oil ratio gradually increases, the gasoline output at the top of the tower will also increase slightly. Therefore, in the gas phase depyrolysis coal tar treatment, if a larger amount of gasoline needs to be produced, it can be achieved by increasing the hydrogen-to-oil ratio.

[0121] Example 12

[0122] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.1.

[0123] Embodiment 13

[0124] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.2.

[0125] Embodiment 14

[0126] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.3.

[0127] Embodiment 15

[0128] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.4.

[0129] Example 16

[0130] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.5.

[0131] Embodiment 17

[0132] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.6.

[0133] Embodiment 18

[0134] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.7.

[0135] Embodiment 19

[0136] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.8.

[0137] Embodiment 20

[0138] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:2.9.

[0139] Embodiment 21

[0140] The difference from Example 1 is that the mass ratio of cyclopentadiene to coal tar in the pyrolysis gas is 1:3.0.

[0141] The test results of heavy tar yield and the proportion of heavy tar with three rings or above under different mass ratios of cyclopentadiene and coal tar in pyrolysis gas are compared in Table 9.

[0142] Table 9 Test results at different ratios

[0143]

[0144] It can be seen from Table 9 that with the increasing use of the ring-increasing modifier - cyclopentadiene, the output of heavy tar and the proportion of three-ring or higher ring compounds continue to increase. This shows that the ring-increasing modifier can achieve the ring-increasing modification of gas-phase pyrolysis coal tar, thereby realizing the recycling of heavy tar.

[0145] 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 the present invention, although the present invention has been described in detail with reference to the preferred embodiments. It should be understood by those skilled in the art that the technical solutions of the present invention can still be modified or replaced by equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. An integrated reactor for realizing a gas phase pyrolysis coal tar ring-increasing modification and graded hydrogenation process, characterized in that: comprising a reactive distillation tower (a), The interior of the reactive distillation tower (a) is divided into a distillation section and a ring-increasing modification section from top to bottom; The ring-adding modification section is used to perform ring-adding modification on gas-phase pyrolysis coal tar; the distillation section is used to perform graded hydrogenation on the gas-phase pyrolysis coal tar after ring-adding modification; In the ring-increasing and modifying section, a pyrolysis gas feed port (3), a bottom product discharge port (4) and a gas phase reflux port (5) are respectively arranged at the bottom of the reaction distillation tower (a), and a ring-increasing and modifying agent inlet (6) is arranged on the tower side of the reaction distillation tower (a); In the distillation section, a primary reaction section (8) and a secondary reaction section (12) are sequentially arranged in the reaction distillation tower (a) from bottom to top; a H2 inlet (17) and a side product outlet (13) are respectively arranged on the tower side of the reaction distillation tower (a), the H2 inlet (17) is located between the primary reaction section (8) and the secondary reaction section (12), the side product outlet (13) is located on the upper part of the secondary reaction section (12), and a tower top tail gas outlet (15) and a liquid phase reflux inlet (14) are respectively arranged on the tower top of the reaction distillation tower (a).

2. The integrated reactor according to claim 1, characterized in that: A gas phase distribution device (2) is also provided in the ring-adding and modifying section of the reaction distillation tower (a); the gas phase distribution device (2) is located between the gas phase reflux inlet (5) and the ring-adding and modifying agent inlet (6), and is connected to the pyrolysis gas feed inlet (3).

3. The integrated reactor according to claim 2, characterized in that: The integrated reactor further comprises a liquid redistributor (10) and a liquid collector (11) respectively arranged between the primary reaction section (8) and the secondary reaction section (12); the liquid redistributor (10) is located below the liquid collector (11), and the liquid redistributor (10) is located above the H2 inlet (17).

4. The integrated reactor according to claim 3, characterized in that: The integrated reactor further comprises a liquid redistributor (10) and a liquid collector (11) which are arranged above the secondary reaction section (12); the liquid redistributor (10) is close to the secondary reaction section (12).

5. The integrated reactor according to claim 1, characterized in that: The integrated reactor further comprises a tray (16) arranged between the primary reaction section (8) and the secondary reaction section (12) and at the top of the secondary reaction section (12).

6. The integrated reactor according to claim 5, characterized in that: The number of the tower plates (16) between the primary reaction section (8) and the secondary reaction section (12) is 4 to 8; the number of the tower plates (16) above the secondary reaction section (12) is 12 to 18.

7. The integrated reactor according to any one of claims 1 to 6, characterized in that: The primary reaction section (8) comprises a packing support plate (7), a first catalyst layer and a packing pressure plate (9) stacked in sequence from bottom to top; the secondary reaction section (12) comprises a packing support plate (7), a second catalyst layer and a packing pressure plate (9) connected in sequence from bottom to top; the first catalyst layer is a Ni / Al2O3 catalyst layer; and the second catalyst layer is a Ni-Mo / Al2O3 catalyst layer.

8. The gas phase pyrolysis coal tar ring-increasing modification and graded hydrogenation process based on the integrated reactor according to claim 7 is characterized in that: The gas phase pyrolysis coal tar ring-increasing modification and graded hydrogenation process comprises the following steps: S1, ring-addition modification The gas phase pyrolysis coal tar is introduced into the reaction distillation tower (a) from the pyrolysis gas feed port (3), and the ring-increasing modifier is introduced into the reaction distillation tower (a) through the ring-increasing modifier inlet (6); under the action of the ring-increasing reaction catalyst, the gas phase pyrolysis coal tar and the ring-increasing modifier undergo a ring-increasing modification reaction to obtain a heavy component and a light component; S2, staged hydrogenation The heavy components of step S1 are extracted from the bottom product outlet (4) and heated in a kettle reboiler (b) to obtain heavy tar and gas phase, and the gas phase is refluxed to the ring-increasing modification section through the gas phase reflux inlet (5); The light components in step S1 are hydrogenated by dissolving hydrogen at low temperature in the primary reaction section (8), mixed with the high temperature hydrogen coming from the H2 inlet (17), and then hydrogenated at high temperature in the secondary reaction section (12) to obtain a reaction product; S3. Separation The reaction product of step S2 is separated to obtain a diesel fraction and a residual component; the diesel fraction is extracted from the side product outlet (13); the residual component is discharged from the tail gas outlet (15) at the top of the tower and then cooled and separated to obtain a liquid phase and tail gas; a part of the liquid phase is refluxed to the distillation section through the liquid phase reflux inlet (14), another part of the liquid phase is collected, a part of the tail gas is discharged, and a part of the tail gas is circulated as high-temperature hydrogen.

9. The process for ring-increasing and modification of gas-phase pyrolysis coal tar by graded hydrogenation according to claim 1, characterized in that: In the ring-addition modification of step S1, The ring-increasing modifier is cyclopentadiene, and the ring-increasing reaction catalyst is AlCl3; the coal tar content in the gas-phase pyrolysis coal tar is 5wt% to 10wt%; the feed flow rate of the gas-phase pyrolysis coal tar is 2L / h to 6L / h, and the mass ratio of coal tar, ring-increasing modifier and ring-increasing reaction catalyst in the gas-phase pyrolysis coal tar is 1:2 to 3:10, the pressure is 1MPa to 2MPa; and the temperature is 100°C to 120°C.

10. The process for ring-enhancing and modification of gas-phase pyrolysis coal tar by graded hydrogenation according to claim 9, characterized in that: In step S2, the volume ratio of high-temperature hydrogen to gas-phase pyrolysis coal tar is 1:1000-1300; the high-temperature hydrogen consists of two parts: fresh hydrogen and circulating hydrogen, the volume of circulating hydrogen accounts for 60%-80% of the total volume of high-temperature hydrogen, and the temperature of high-temperature hydrogen is 400°C-420°C; the circulating hydrogen comes from tail gas.

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