阅读说明：本技术 油系针状焦原料深减压预处理系统 (Deep decompression pretreatment system for oil-based needle coke raw material ) 是由 牛永峰 任晶 徐�明 张可意 徐仁策 于 2021-09-26 设计创作，主要内容包括：本发明公开了一种油系针状焦原料深减压预处理系统,包括加热炉,减压塔,减压汽提塔,一线油出系统,二线油出系统,三线油出系统,顶污油出系统,沥青油出系统,油浆换热系统,所述减压塔从上到下依次与顶污油出系统、一线油出系统、减压汽提塔、沥青油出系统相连；所述减压汽提塔上半部与二线油出系统相连,下半部与三线油出系统相连；所述换热系统与各个换热器相连。本发明提供的油系针状焦原料深减压预处理系统将原料油浆深减压分离为一线油、二线油和三线油,实现了油浆的多级分离,组分更加简单,有利于进行后续的焦化处理,得到质量更高的针状焦产品。(The invention discloses an oil-based needle coke raw material deep decompression pretreatment system which comprises a heating furnace, a decompression tower, a decompression stripping tower, a first-line oil outlet system, a second-line oil outlet system, a third-line oil outlet system, a top dirty oil outlet system, an asphalt oil outlet system and an oil slurry heat exchange system, wherein the decompression tower is sequentially connected with the top dirty oil outlet system, the first-line oil outlet system, the decompression stripping tower and the asphalt oil outlet system from top to bottom; the upper half part of the reduced pressure stripping tower is connected with the second-line oil outlet system, and the lower half part of the reduced pressure stripping tower is connected with the third-line oil outlet system; the heat exchange system is connected with each heat exchanger. The deep decompression pretreatment system for the oil-based needle coke raw material provided by the invention separates the raw material oil slurry into the first-line oil, the second-line oil and the third-line oil through deep decompression, realizes multi-stage separation of the oil slurry, has simpler components, is beneficial to subsequent coking treatment, and obtains a needle coke product with higher quality.)

1. A deep decompression pretreatment system for oil-based needle coke raw materials is characterized by comprising a heating furnace, a decompression tower, a decompression stripping tower, a first-line oil outlet system, a second-line oil outlet system, a third-line oil outlet system, a top dirty oil outlet system, an asphalt oil outlet system and an oil slurry heat exchange system,

the heating furnace is connected with the decompression tower;

the vacuum tower comprises an intermediate oil pump and an intermediate oil heat exchanger, and is sequentially connected with a top sump oil outlet system, a first-line oil outlet system, a vacuum stripping tower and an asphalt oil outlet system from top to bottom;

the upper half part of the reduced pressure stripping tower is connected with the second-line oil outlet system, and the lower half part of the reduced pressure stripping tower is connected with the third-line oil outlet system;

the first-line oil outlet system comprises a first-line heat exchanger of a pressure reducing tower;

the second-line oil outlet system comprises a first heat exchanger on the second line of the vacuum tower, a second heat exchanger on the second line of the vacuum tower and a third heat exchanger on the second line of the vacuum tower;

the three-line oil outlet system comprises a first decompression tower three-line heat exchanger, a second decompression tower three-line heat exchanger and a third decompression tower three-line heat exchanger;

the asphalt oil outlet system comprises an asphalt oil first heat exchanger, an asphalt oil second heat exchanger and an asphalt oil third heat exchanger;

and the heat exchange system is connected with each heat exchanger and is used for exchanging heat between the oil slurry and each separated substance.

2. The deep decompression pretreatment system for oil-based needle coke raw material according to claim 1, wherein the one-line oil outlet system further comprises a vacuum tower one-line oil pump, a vacuum tower one-line reflux cooler, and the one-line oil is separated by the vacuum tower and then sequentially enters the one-line oil storage device through the vacuum tower one-line oil pump, the vacuum tower one-line heat exchanger and the vacuum tower one-line reflux cooler.

3. The deep decompression pretreatment system for oil-based needle coke raw material according to claim 1, wherein the two-line oil outlet system further comprises a two-line oil pump of the decompression tower, the two-line oil pump of the decompression tower is delivered to a cooler, and the two-line oil is separated by the decompression stripping tower and then sequentially passes through the two-line oil pump of the decompression tower, the two-line first heat exchanger of the decompression tower, the two-line second heat exchanger of the decompression tower, the two-line third heat exchanger of the decompression tower and the two-line delivery cooler of the decompression tower to enter the two-line oil storage device.

4. The deep decompression pretreatment system for oil-based needle coke raw material according to claim 1, wherein the three-wire oil outlet system further comprises a decompression tower three-wire oil pump, a decompression tower three-wire outward-feeding cooler, and the three-wire oil is separated by the decompression stripping tower and then sequentially passes through the decompression tower three-wire oil pump, the decompression tower three-wire first heat exchanger, the decompression tower three-wire second heat exchanger, the decompression tower three-wire third heat exchanger and the decompression tower three-wire outward-feeding cooler to enter the three-wire oil storage device.

5. The deep decompression pretreatment system for the oil-based needle coke raw material according to claim 1, wherein the top effluent oil discharge system comprises a first-stage condenser, a second-stage condenser, a third-stage condenser, an oil-water separation device, a decompression tower top vacuum pump, a decompression tower top oil pump, a decompression tower top water pump, wherein the top effluent oil is separated by a decompression tower, sequentially passes through the first-stage condenser and the second-stage condenser, enters the oil-water separation device through the third-stage condenser, is evacuated of non-condensable gas by the decompression tower top vacuum pump, is discharged into a top effluent oil storage device through the decompression tower top oil pump, and is discharged into the top effluent water storage device through the decompression tower top water pump.

6. The deep decompression pretreatment system for oil-based needle coke raw material according to claim 1, wherein the bitumen oil outlet system further comprises a decompression tower bottom pump, the bottom oil of the decompression tower is sent out to a cooler, and the bitumen oil is separated by the decompression tower and then sequentially passes through the decompression tower bottom pump, the first bitumen oil heat exchanger, the second bitumen oil heat exchanger, the third bitumen oil heat exchanger and the bottom oil of the decompression tower to be sent out to the cooler and then enters the bitumen oil storage device.

7. The deep decompression pretreatment system for oil-based needle coke raw material according to claim 1, wherein the connection sequence of each heat exchanger in the heat exchange system is as follows: the method comprises the following steps of slurry oil, a first-line heat exchanger of a decompression tower, a second-line third heat exchanger of the decompression tower, a third heat exchanger of a third-line of the decompression tower, an asphalt oil third heat exchanger, a second-line second heat exchanger of the decompression tower, an oil-in-oil heat exchanger, a third-line second heat exchanger of the decompression tower, an asphalt oil second heat exchanger, a first heat exchanger of the second-line first heat exchanger of the decompression tower, a first heat exchanger of the third-line of the decompression tower, an asphalt oil first heat exchanger and a heating furnace.

Technical Field

The invention belongs to the field of needle coke production equipment, and particularly relates to a deep decompression pretreatment system for an oil-based needle coke raw material.

Background

The needle coke is a high-performance carbon material, has clear surface lines, is a rectangular strip sheet after being crushed, can observe a fiber structure under a microscope, has the excellent characteristics of small thermal expansion coefficient, high graphitization degree, heat resistance, corrosion resistance, high anisotropy degree and the like, and is widely applied to the fields of high-power (HP) and ultra-high-power (UHP) graphite electrodes, special functional materials, composite carbon materials thereof and the like.

The needle coke can be divided into two types of coal-based needle coke and petroleum needle coke according to different production raw materials, generally, the petroleum needle coke has better performance than the coal-based needle coke, the graphitization degree is higher, and the produced electrode material has stronger conductive capability. The raw material of the petroleum needle coke is required to be high in short-side chain polycyclic aromatic hydrocarbon content and low in colloidal asphalt content, and the catalytic oil slurry is rich in short-side chain polycyclic aromatic hydrocarbon and is one of excellent raw materials of the oil-system needle coke. However, the catalytic slurry oil has complex components and wide distillation range, and not only has lighter micromolecule substances, but also has heavy-molecular-weight fused aromatic hydrocarbons, in the carbonization process, the micromolecules or overflow systems or liquid phase mobile phases are generated, the alkane content in the micromolecule substances is high, the reaction intensity is accelerated, the expansion of intermediate phases is not facilitated, the fused ring macromolecules need to react at higher temperature and are easily aggregated into large coking particles, so that the catalytic slurry oil needs to be pretreated to reduce light components and macromolecular substances which are not conducive to coking reaction in the slurry oil, and the residual components of the slurry oil are more conducive to the generation of needle coke. At present, the commonly used pretreatment method is a reduced pressure distillation process, and after solid particles and oil residues of catalytic slurry oil are removed by a reduced pressure distillation device, aromatic hydrocarbon components are extracted to be used as raw materials for producing needle coke.

Chinese patent CN201810504927.7 discloses a process for producing needle coke raw oil by filtering catalytic slurry oil and a system thereof, wherein the catalytic slurry oil is pretreated by a filtration-vacuum distillation method, and separated to obtain an upper-stage oil mainly comprising saturated hydrocarbons, a middle-stage oil mainly comprising polycyclic aromatic hydrocarbons and a small amount of polycyclic aromatic hydrocarbons, and a lower-stage oil mainly comprising colloids and asphaltenes, and the middle-stage oil mainly comprising polycyclic aromatic hydrocarbons and a small amount of polycyclic aromatic hydrocarbons is used as the needle coke raw material. However, the middle oil is still a mixture of various fractions, and needs to be further separated to obtain a higher-quality needle coke product, and meanwhile, the prior art has the defects of high energy consumption and high steam production cost.

Disclosure of Invention

The invention aims to solve the defects of the prior art and provide the deep decompression pretreatment system for the oil-based needle coke raw material, which can carry out multi-stage separation on oil slurry and has low steam production cost.

In order to achieve the purpose, the invention adopts the technical scheme that:

the invention provides an oil system needle coke raw material deep decompression pretreatment system, which comprises a heating furnace, a decompression tower, a decompression stripping tower, a first-line oil outlet system, a second-line oil outlet system, a third-line oil outlet system, a top dirty oil outlet system, an asphalt oil outlet system and an oil slurry heat exchange system,

the heating furnace is connected with the decompression tower and is used for heating the oil slurry after heat exchange;

the vacuum tower comprises a medium oil pump and a medium oil heat exchanger in the vacuum tower, and is sequentially connected with a top dirty oil outlet system, a first-line oil outlet system, a vacuum stripping tower and an asphalt oil outlet system from top to bottom, and is used for separating oil slurry into top dirty oil, first-line oil, middle-section oil and asphalt oil under reduced pressure;

the upper half part of the reduced-pressure stripping tower is connected with the second-line oil outlet system, and the lower half part of the reduced-pressure stripping tower is connected with the third-line oil outlet system and used for further reducing pressure and separating the middle-section oil into second-line oil and third-line oil;

the first-line oil outlet system comprises a first-line heat exchanger of the pressure reducing tower and is used for conveying separated first-line oil;

the second-line oil outlet system comprises a first heat exchanger on the second line of the vacuum tower, a second heat exchanger on the second line of the vacuum tower and a third heat exchanger on the second line of the vacuum tower, and is used for conveying the separated second-line oil;

the three-line oil outlet system comprises a first decompression tower three-line heat exchanger, a second decompression tower three-line heat exchanger and a third decompression tower three-line heat exchanger, and is used for conveying separated three-line oil;

the top dirty oil outlet system is used for conveying the separated top dirty oil;

the asphalt oil outlet system comprises an asphalt oil first heat exchanger, an asphalt oil second heat exchanger and an asphalt oil third heat exchanger, and is used for conveying separated asphalt oil;

and the heat exchange system is connected with each heat exchanger and is used for exchanging heat between the oil slurry and each separated substance.

Preferably, the first-line oil outlet system further comprises a first-line oil pump of the vacuum tower, a first-line reflux cooler of the vacuum tower, and the first-line oil is separated by the vacuum tower and then enters the first-line oil storage device through the first-line oil pump of the vacuum tower, the first-line heat exchanger of the vacuum tower and the first-line reflux cooler of the vacuum tower in sequence.

Preferably, the two-line oil outlet system further comprises a pressure reducing tower two-line oil pump, the pressure reducing tower two-line external cooler, and the two-line oil is separated by the pressure reducing tower two-line oil pump, the pressure reducing tower two-line first heat exchanger, the pressure reducing tower two-line second heat exchanger, the pressure reducing tower two-line third heat exchanger and the pressure reducing tower two-line external cooler to enter the two-line oil storage device.

Preferably, the three-line oil outlet system further comprises a vacuum tower three-line oil pump, the vacuum tower three-line delivery cooler, and the three-line oil is separated by the vacuum stripping tower and then sequentially enters the three-line oil storage device through the vacuum tower three-line oil pump, the vacuum tower three-line first heat exchanger, the vacuum tower three-line second heat exchanger, the vacuum tower three-line third heat exchanger and the vacuum tower three-line delivery cooler.

Preferably, the top dirty oil outlet system comprises a first-level condenser, a second-level condenser, a third-level condenser, an oil-water separation device, a vacuum pump at the top of the vacuum tower, an oil pump at the top of the vacuum tower, a water pump at the top of the vacuum tower, the top dirty oil after being separated by the vacuum tower sequentially passes through the first-level condenser and the second-level condenser, the third-level condenser enters the oil-water separation device, then the non-condensable gas is emptied by the vacuum pump at the top of the vacuum tower, the top dirty oil is discharged into a top dirty oil storage device by the oil pump at the top of the vacuum tower, and the top dirty water is discharged into a top dirty water storage device by the water pump at the top of the vacuum tower.

Preferably, the asphalt oil discharging system further comprises a vacuum tower bottom pump, the vacuum tower bottom oil is sent to a cooler, and the asphalt oil is separated by the vacuum tower and then enters the asphalt oil storage device through the vacuum tower bottom pump, the asphalt oil first heat exchanger, the asphalt oil second heat exchanger, the asphalt oil third heat exchanger and the vacuum tower bottom oil sending cooler in sequence.

Preferably, the connection order of each heat exchanger in the heat exchange system is as follows in sequence: the method comprises the steps of oil slurry, a first-line heat exchanger of a pressure reducing tower, a second-line third heat exchanger of the pressure reducing tower, a third heat exchanger of a third-line heat exchanger of the pressure reducing tower, an asphalt oil third heat exchanger, a second-line second heat exchanger of the pressure reducing tower, an oil heat exchanger in the pressure reducing tower, a third-line second heat exchanger of the pressure reducing tower, an asphalt oil second heat exchanger, a first heat exchanger of a second-line first heat exchanger of the pressure reducing tower, a first heat exchanger of the third-line heat exchanger of the pressure reducing tower, an asphalt oil first heat exchanger and a heating furnace, wherein the heat exchange temperature of the oil slurry is gradually increased, the heat recovery is realized to the maximum degree, and the energy consumption is reduced.

Compared with the prior art, the deep decompression pretreatment system for the oil-based needle coke raw material, provided by the invention, separates the raw material oil slurry into the first-line oil, the second-line oil and the third-line oil through deep decompression by using the decompression tower and the decompression stripping tower, realizes multi-stage separation of the oil slurry, has simpler components, is beneficial to subsequent coking treatment and obtains a needle coke product with higher quality compared with the prior art in which the raw material oil slurry can only be separated into the middle-stage oil; the raw material oil slurry and each separated oil are subjected to heat exchange through the heat exchange system, so that the maximum recovery of heat is realized, and the energy consumption and the steam production cost are obviously reduced.

Drawings

FIG. 1 is a flow chart showing the design of the deep reduced pressure pretreatment system for oil-based needle coke raw material, and FIG. 2 is a schematic connection diagram showing the heat exchange system of the deep reduced pressure pretreatment system for oil-based needle coke raw material.

Wherein, 1, a heating furnace; 2-a vacuum tower; 21-medium oil pump; 22-medium oil heat exchanger; 3-decompression stripping tower; 41-a vacuum tower first-line oil pump; 42-a pressure reducing tower first-line heat exchanger; 43-a vacuum column first line reflux cooler; 51-a vacuum tower two-line oil pump; 52-a second-line first heat exchanger of the vacuum tower; 53-two-line second heat exchanger of the vacuum tower; 54-a second-line third heat exchanger of the decompression tower; 55-a second-line delivery cooler of the decompression tower; 61-a vacuum tower three-line oil pump; 62-a three-line first heat exchanger of the vacuum tower; 63-a three-line second heat exchanger of the pressure reduction tower; 64-a three-line third heat exchanger of the vacuum tower; 65-decompression tower three-line delivery cooler; 71-a primary condenser; 72-a secondary condenser; 73-a three-stage condenser; 74-oil-water separation device; 75-vacuum column top vacuum pump; 76-vacuum overhead oil pump; 77-vacuum tower top water pump; 81-vacuum tower bottom pump; 82-bitumen oil first heat exchanger; 83-bitumen oil second heat exchanger; 84-bitumen oil third heat exchanger; 85-sending the bottom oil of the vacuum tower to a cooler.

Detailed Description

For a better understanding of the present invention, specific embodiments thereof are described in further detail below with reference to the accompanying drawings.

As shown in the attached drawings 1 and 2, the deep decompression pretreatment system for the oil-based needle coke raw material, provided by the invention, comprises a heating furnace 1, a decompression tower 2, a decompression stripping tower 3, a first-line oil outlet system, a second-line oil outlet system, a three-line oil outlet system, a top dirty oil outlet system, an asphalt oil outlet system and an oil slurry heat exchange system, wherein the heating furnace 1 is connected with the decompression tower 2, the decompression tower 2 comprises a medium oil pump 21 and a medium oil heat exchanger 22, and the top dirty oil outlet system, the first-line oil outlet system, the decompression stripping tower and the asphalt oil outlet system are sequentially connected from top to bottom; the upper half part of the reduced-pressure stripping tower 3 is connected with the second-line oil outlet system, and the lower half part of the reduced-pressure stripping tower is connected with the third-line oil outlet system; the one-line oil outlet system comprises a pressure reducing tower one-line oil pump 41, a pressure reducing tower one-line heat exchanger 42 and a pressure reducing tower one-line reflux cooler 43; the two-line oil outlet system comprises a two-line oil pump 51 of the decompression tower, a two-line first heat exchanger 52 of the decompression tower, a two-line second heat exchanger 53 of the decompression tower, a two-line third heat exchanger 54 of the decompression tower and a two-line delivery cooler 55 of the decompression tower; the three-line oil outlet system comprises a decompression tower three-line oil pump 61, a decompression tower three-line first heat exchanger 62, a decompression tower three-line second heat exchanger 63, a decompression tower three-line third heat exchanger 64 and a decompression tower three-line delivery cooler 65; the top dirty oil outlet system comprises a first-stage condenser 71, a second-stage condenser 72, a third-stage condenser 73, an oil-water separation device 74, a vacuum pump 75 at the top of the vacuum tower, an oil pump 76 at the top of the vacuum tower and a water pump 77 at the top of the vacuum tower; the asphalt oil outlet system comprises a vacuum tower bottom pump 81, an asphalt oil first heat exchanger 82, an asphalt oil second heat exchanger 83, an asphalt oil third heat exchanger 84 and a vacuum tower bottom oil delivery cooler 85; the connection sequence of each heat exchanger in the heat exchange system is as follows: the method comprises the steps of oil slurry-a first-line heat exchanger 41 of a decompression tower, a second-line third heat exchanger 54 of the decompression tower, a third-line third heat exchanger 64 of the decompression tower, a third asphalt oil heat exchanger 83, a second-line second heat exchanger 53 of the decompression tower, an oil heat exchanger 22 of the decompression tower, a third-line second heat exchanger 63 of the decompression tower, a second asphalt oil heat exchanger 83, a first heat exchanger 52 of the decompression tower, a first heat exchanger 62 of the decompression tower, a first asphalt oil heat exchanger 82 and a heating furnace 1.

In actual production, raw material slurry oil enters a heating furnace 1 after being preheated by a heat exchange system, enters a decompression tower 2 for decompression separation after reaching 400 ℃, wherein linear oil is separated at 160-240 ℃, and enters a linear oil storage device after sequentially passing through a linear oil pump 41 of the decompression tower, a linear heat exchanger 42 of the decompression tower and a linear reflux cooler 43 of the decompression tower; separating middle section oil at 270-340 ℃, further separating the middle section oil in a pressure reduction stripping tower 3, separating second line oil at 290-320 ℃, sequentially passing through a pressure reduction tower second line oil pump 51, a pressure reduction tower second line first heat exchanger 52, a pressure reduction tower second line second heat exchanger 53, a pressure reduction tower second line third heat exchanger 54 and a pressure reduction tower second line external cooler 55, and then entering a second line oil storage device; separating three-line oil at 320-340 ℃, sequentially passing through a vacuum tower three-line oil pump 61, a vacuum tower three-line first heat exchanger 62, a vacuum tower three-line second heat exchanger 63, a vacuum tower three-line third heat exchanger 64 and a vacuum tower three-line delivery cooler 65, and then entering a three-line oil storage device; separating out asphalt oil at the temperature of more than 340 ℃, and feeding the asphalt oil into an asphalt oil storage device after passing through a vacuum tower bottom pump 81, an asphalt oil first heat exchanger 82, an asphalt oil second heat exchanger 83, an asphalt oil third heat exchanger 84 and a vacuum tower bottom oil delivery cooler 85 in sequence; the top dirty oil is separated out from the top, and enters an oil-water separation device 74 through a first-stage condenser 71, a second-stage condenser 72 and a third-stage condenser 73 in sequence, then the non-condensable gas is evacuated through a vacuum pump 75 at the top of the vacuum tower, the top dirty oil is discharged into a top dirty oil storage device through an oil pump 76 at the top of the vacuum tower, and the top dirty water is discharged into the top dirty water storage device through a water pump 77 at the top of the vacuum tower. In the embodiment, the original oil slurry is further separated into the first-line oil, the second-line oil and the third-line oil through the pressure reducing tower 2 and the pressure reducing stripping tower 3, so that the multistage separation of the oil slurry is realized, the subsequent coking treatment is facilitated, and the high-quality oil-based needle coke product is obtained.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.