System for preparing needle coke raw material from catalytic slurry oil

Abstract

A system for preparing a needle coke raw material from catalytic slurry oil comprises a raw material tank, an outlet of the raw material tank is connected with an inlet of a raw material pump, an outlet of the raw material pump is connected with a bottom inlet of a multiphase flow hydrogenation reactor after being mixed with an outlet of a recycle hydrogen compressor through a pipeline, and an outlet of the multiphase flow hydrogenation reactor is connected with an inlet of a primary separator. A gas-phase product outlet in the top of the primary separator is connected with an inlet of a secondary separator, a liquid-phase product outlet in the bottom of the primary separator is connected with an inlet of a vacuum tower, and heavy distillate oil and solid-containing oil residues are obtained through fractionation of the vacuum tower; a gas product outlet in the top of the secondary separator is connected with an inlet of a circulating hydrogen compressor to form circulation; a liquid product outlet at the bottom of the secondary separator is connected with an inlet of the fractionating tower, and naphtha fraction and medium fraction oil are obtained through the fractionating tower. Through the empty barrel structure of the multiphase flow hydrogenation reactor, the reaction form is similar to plug flow, the problems of deposition and blockage in the reactor do not exist, and deep purification treatment of catalytic slurry oil is realized.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the needle coke preparation technical field, concretely relates to a system for preparing needle coke raw material from catalytic slurry oil. BACKGROUND

[0002] Catalytic slurry oil contains a large amount of aromatic hydrocarbons, which is a high-quality raw material for producing needle coke. However, due to the presence of a certain amount of catalyst powder and impurity elements such as sulfur and nitrogen, it needs to be sequentially treated by desolidification and hydrogenation to obtain suitable needle coke raw material. Currently, the desolidification of catalytic slurry oil mainly adopts methods such as sedimentation, centrifugal separation, mechanical filtration, and electrostatic separation, and the removal of sulfur and nitrogen mainly adopts the method of hydrogenation treatment.

[0003] CN103789028A discloses a pretreatment method for producing needle coke raw material from catalytic slurry oil. After filtration, the catalytic slurry oil is subjected to mild hydrogenation treatment. 20%-50% (by weight) of the hydrogenated oil is sent to a vacuum distillation device, and the operating conditions are pressure 5mmHg-100mmHg and temperature 300-450℃. The obtained hydrogenated light distillate oil is mixed with the remaining hydrogenated oil to be used as a raw material for producing needle coke. This patent adopts the technical idea of filtering and then mild hydrogenation treatment. However, it has problems such as easy clogging of the filter by catalyst powder, frequent switching of the filter, high frequency of replacing the filter element, and difficulty in cleaning, which cannot realize long-period operation.

[0004] CN103013567A discloses a method for producing needle coke raw material from catalytic cracking slurry oil. The invention sets up a protection zone and a hydrogenation reaction zone. The catalytic cracking slurry oil first enters the protection zone to adsorb and remove most of the catalyst powder, then mixes with hydrogen gas in a heating furnace, and after heating, enters the hydrogenation reaction zone for hydrogenation treatment reaction. This patent sets up a protection zone before the hydrogenation reaction zone. However, the catalyst powder in the catalytic slurry oil is easy to deposit in the protection zone, which causes the reactor bed to be blocked and affects the long-period operation of the device.

[0005] In summary, the above-mentioned methods of physical filtration or setting up a protection zone to remove catalyst powder, and then removing impurity elements such as sulfur and nitrogen by hydrogenation treatment to obtain needle coke raw material that meets the requirements, all have problems such as long process flow, easy clogging of the device, and difficulty in stable operation. SUMMARY

[0006] In order to overcome the defects of the above-mentioned prior art, the purpose of the utility model is to provide a system for preparing needle coke raw material from catalytic slurry oil. The system has an empty barrel structure of a multiphase flow hydrogenation reactor, which makes the reaction form similar to plug flow, and there is no problem of deposition and blockage in the reactor. The system realizes deep purification treatment of catalytic slurry oil, has characteristics such as short process flow, low cost, and strong stability.

[0007] In order to achieve the above object, the technical scheme adopted by the utility model is:

[0008] A system for preparing needle coke raw material from catalytic oil slurry, comprising a raw material tank 1, the outlet of the raw material tank 1 is connected with the inlet of a raw material pump 2, the outlet of the raw material pump 2 is connected with the outlet of a circulating hydrogen compressor 7 through a pipeline after mixing, and the outlet of a multiphase flow hydrogenation reactor 3 is connected with the inlet of a primary separator 4, the top gas phase product outlet of the primary separator 4 is connected with the inlet of a secondary separator 5, the bottom liquid phase product outlet of the primary separator 4 is connected with the inlet of a vacuum tower 10, and heavy distillate oil 11 and solid-containing oil residue 12 are obtained through fractional distillation of the vacuum tower 10;

[0009] The top gas product outlet of the secondary separator 5 is connected with the inlet of the circulating hydrogen compressor 7, forming a circulation.

[0010] The bottom liquid product outlet of the secondary separator 5 is connected with the inlet of a fractional distillation column 6, and naphtha distillate 8 and medium distillate oil 9 are obtained through the fractional distillation column 6.

[0011] The multiphase flow hydrogenation reactor 3 is a suspended bed or a boiling bed.

[0012] The multiphase flow hydrogenation reactor 3 is a hollow barrel structure.

[0013] The reaction temperature of the multiphase flow hydrogenation reactor 3 is 200-400 DEG C, the pressure is 1-5 MPa, the space velocity is 0.3-3.0 h -1 , and the hydrogen oil ratio is 300-2000 NL / kg.

[0014] One or both of the medium distillate oil 9 and the heavy distillate oil 11 constitute needle coke raw material, and the proportion of the medium distillate oil and the heavy distillate oil can be flexibly adjusted to obtain needle coke raw material oil with different properties according to the quality requirements of needle coke products.

[0015] The utility model discloses the beneficial effect:

[0016] The utility model discloses the multiphase flow hydrogenation reactor can handle high solid content catalytic oil slurry, need not set up the solid removing unit in the front end, can effectively shorten the technological process.

[0017] When the utility model is handled solid-containing catalytic oil slurry, the hollow barrel structure of the multiphase flow reactor is combined, there is no internal component, the catalyst carrier is porous carbon material, can adsorb catalyst fine powder, has hydrogenation function simultaneously, reaches the purpose of removing catalyst powder and sulfur nitrogen and other impurities.

[0018] The medium distillate oil and the heavy distillate oil obtained by the utility model can flexibly adjust the proportion of the medium distillate oil and the heavy distillate oil according to the quality of needle coke products, and obtain raw material oil for producing needle coke with different qualities. DRAWINGS

[0019] Figure 1 This is a process flow diagram for the preparation of needle coke feedstock from catalytic oil slurry.

[0020] In the diagram: 1-Feed tank; 2-Feed pump; 3-Multiphase flow hydrogenation reactor; 4-First-stage separator; 5-Second-stage separator; 6-Fracturing tower; 7-Circulating hydrogen compressor; 8-Naphtha fraction; 9-Middle oil fraction; 10-Vacuum distillation tower; 11-Heavy distillate oil; 12-Solid-containing oil residue. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings.

[0022] like Figure 1 As shown, a system for producing needle coke feedstock from catalytic oil slurry includes a feedstock tank 1. The outlet of the feedstock tank 1 is connected to the inlet of a feedstock pump 2. The outlet of the feedstock pump 2 is mixed with the outlet of a circulating hydrogen compressor 7 through a pipeline and then connected to the bottom inlet of a multiphase flow hydrogenation reactor 3. The outlet of the multiphase flow hydrogenation reactor 3 is connected to the inlet of a primary separator 4. The top gaseous product outlet of the primary separator 4 is connected to the inlet of a secondary separator 5. The top gaseous product outlet of the secondary separator 5 is connected to the inlet of the circulating hydrogen compressor 7, forming a cycle.

[0023] The liquid product outlet at the bottom of the secondary separator 5 is connected to the inlet of the fractionation tower 6, and naphtha fraction 8 and medium distillate oil 9 are obtained through the fractionation tower 6.

[0024] The liquid product outlet at the bottom of the primary separator 4 is connected to the inlet of the vacuum distillation tower 10. The heavy distillate oil 11 and solid residue 12 are obtained by fractionation in the vacuum distillation tower 10.

[0025] The multiphase flow hydrogenation reactor 3 is a suspended bed, a fluidized bed, or a combination thereof.

[0026] When processing solid-containing catalytic oil slurry, the multiphase flow hydrogenation reactor 3 combines the fact that the multiphase flow reactor has no internal components and the catalyst support is a porous carbon material that can adsorb fine catalyst powder and has a hydrogenation function to achieve the purpose of removing catalyst powder and impurities such as sulfur and nitrogen.

[0027] The multiphase flow hydrogenation reactor 3 is an empty barrel structure.

[0028] The multiphase flow hydrogenation reactor 3 operates at a reaction temperature of 200-400℃, a pressure of 1-5 MPa, and a space velocity of 0.3-3.0 h⁻¹. -1 Hydrogen-to-oil ratio 300-2000 NL / kg.

[0029] The used catalyst is a solid catalyst, the addition amount is 0.5-5.0% based on the mass fraction of the total feed amount, the average particle size is 75 μm, the active component is one or several of Fe, Ni, Mo and W, the content is 5-30%, and the carrier is a high-carbon porous material, which can be coal-based activated carbon, bio-based activated carbon or petroleum coke, etc.

[0030] The catalyst is a supported type, a porous carbon material is selected as the carrier, and the active component is loaded on the surface of the carrier to form the supported catalyst.

[0031] The needle coke raw material includes one or a mixture of both of the middle fraction oil 9 and the heavy fraction oil 11, and the proportion can be flexibly adjusted to obtain needle coke raw oil with different properties according to the quality requirements of the needle coke product.

[0032] The working principle of the utility model is as follows:

[0033] The catalytic oil slurry and the carbon-based porous catalyst are prepared into a uniform slurry in the raw material tank 1, mixed with hydrogen in the pipeline at high pressure through the high-pressure feed pump 2, and then enter the multiphase flow hydrogenation reactor 3 to perform hydro-upgrading under mild conditions, the characteristics of the high specific surface of the carbon-based porous catalyst are fully utilized to adsorb solid powder on the catalyst surface, and the hydrogenation active component is utilized to promote the removal of impurity elements such as sulfur and nitrogen, the reaction product is sequentially separated through the primary separator 4 and the secondary separator 5, the gaseous product is separated and returned to the circulating hydrogen compressor 7 as a raw material gas, the liquid product at the bottom of the primary separator 4 enters the vacuum tower 10, and the heavy fraction oil 11 and the solid-containing oil residue 12 are obtained through vacuum distillation, the liquid product at the bottom of the secondary separator 5 enters the fractionating tower 6, and the light naphtha fraction 8 and the middle fraction oil 9 are obtained through separation, and the proportion of the middle fraction oil 9 and the heavy fraction oil 11 is flexibly controlled to obtain needle coke raw material with different properties.

Claims

1. A system for producing needle coke feedstock from catalytic oil slurry, characterized in that, The raw material tank (1) is connected with the raw material pump (2) at the outlet, the outlet of the raw material pump (2) is connected with the outlet of the circulating hydrogen compressor (7) through a pipeline after mixing, and the outlet of the multi-phase flow hydrogenation reactor (3) is connected with the inlet of the primary separator (4) at the bottom, the outlet of the primary separator (4) is connected with the inlet of the secondary separator (5) at the top of the gas phase product, the outlet of the primary separator (4) at the bottom of the liquid phase product is connected with the inlet of the vacuum tower (10), and heavy fraction oil (11) and solid oil residue (12) are obtained through fractionation of the vacuum tower (10); The outlet of the secondary separator (5) at the top of the gas product is connected with the inlet of the circulating hydrogen compressor (7) to form a cycle; The outlet of the secondary separator (5) at the bottom of the liquid product is connected with the inlet of the fractionation tower (6), and naphtha fraction (8) and medium fraction oil (9) are obtained through the fractionation tower (6).

2. The system for producing needle coke raw material from catalytic slurry oil according to claim 1, characterized by, The multi-phase flow hydrogenation reactor (3) is a suspended bed or a boiling bed.

3. The system for producing needle coke raw material from catalytic slurry oil according to claim 1, characterized by, The multi-phase flow hydrogenation reactor (3) is an empty barrel structure.

4. The system for producing needle coke raw material from catalytic slurry oil according to claim 1, characterized by, The multiphase flow hydrogenation reactor (3) has a reaction temperature of 200-400℃, a pressure of 1-5 MPa, a space velocity of 0.3-3.0 h -1 , and a hydrogen / oil ratio of 300-2000 NL / kg.

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