Petroleum atmospheric and vacuum distillation device and process thereof

Abstract

The application provides a petroleum atmospheric and vacuum distillation device and a process thereof, the device comprises a preliminary distillation tower, a negative pressure tower, an atmospheric tower and a vacuum tower connected in sequence, the top of the atmospheric tower and the vacuum tower is respectively connected with an atmospheric tower condenser and a vacuum tower condenser, the lower part of the negative pressure tower is connected with a negative pressure tower reboiler, the hot side outlet of the negative pressure tower reboiler is connected with the atmospheric tower condenser and the vacuum tower condenser through heat exchange pipelines, and the atmospheric tower condenser and the vacuum tower condenser are respectively connected with the inlet of the negative pressure tower reboiler through heat supply pipelines; the negative pressure tower is added in front of the atmospheric tower, the processing capacity of the atmospheric tower is increased, the heating furnace load of the atmospheric tower is reduced, the fractionation precision is improved, the utilization rate of crude oil is effectively improved, the energy loss is reduced, the pull-out rate of the device is increased, an atmospheric tower capacity expansion modification is provided, a new way of energy saving and efficiency increasing is found, and the economic benefit of the device is increased.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of chemical equipment, in particular to a petroleum atmospheric and vacuum distillation device and a process thereof. BACKGROUND

[0002] The atmospheric and vacuum distillation is the first process of petroleum refining. The crude oil after desalting and dewatering is cut into various petroleum fractions in the atmospheric and vacuum distillation device. Since the main equipment of the process includes an initial distillation tower (or a flash tower), an atmospheric heating furnace, an atmospheric tower, a vacuum heating furnace and a vacuum tower, it is simply referred to as a "two-furnace three-tower" three-stage distillation process.

[0003] The atmospheric heating furnace and the vacuum heating furnace are collectively referred to as a heating furnace, which heats the petroleum fractions between the distillation towers. The heating furnace is a part with relatively large energy consumption. The level of atmospheric and vacuum distillation technology is directly related to the quality, yield and economic benefits of subsequent devices.

[0004] The energy saving of the existing atmospheric and vacuum distillation device is to design and optimize the crude oil heat exchange network by using pinch point analysis principle, match various levels of energy, utilize the waste heat as much as possible, increase the mass transfer coefficient of the heat exchanger through the heat exchange network, and improve the energy recovery and utilization efficiency. However, some energy is still wasted. Therefore, it is still necessary to save oil refining cost and save energy.

[0005] The applicant has carried out a detailed search on the prior art, and found the following closest prior art documents:

[0006] The comparative document 1: a petroleum atmospheric and vacuum distillation process with the application number 201110102559.1 provides a technical solution. The raw material inlet of the vacuum distillation tower and / or the atmospheric tower is connected with a tube passage of an inter-wall heat exchanger. The shell passage inlet of the inter-wall heat exchanger is connected with a molten salt heating furnace. The shell passage outlet is connected with a molten tank. The molten salt heating furnace is connected with the molten tank. The mixed inorganic salt powdery particles are added into the molten tank. High-pressure steam or electricity is introduced into the molten tank to melt the mixed inorganic salt powdery particles into liquid. When the melting temperature reaches 180℃, the molten salt circulating pump is started to force the molten salt to circulate in liquid phase, which is transported to the molten salt heating furnace for heating. The molten salt temperature at the outlet of the molten salt furnace or the inlet temperature of the molten salt flow of the inter-wall heat exchanger is controlled at 350℃~530℃. The molten salt is transported to the inter-wall heat exchanger to heat the petroleum flow to 360℃~440℃, and then returned to the molten tank. The petroleum flows out of the inter-wall heat exchanger into the atmospheric tower or the vacuum tower. The method has low probability of coke formation, and can improve the heating temperature and the distillation tower pull rate.

[0007] In the above scheme, the heating furnace before the distillation column in the prior art is replaced by a partition wall heat exchanger for heat exchange between molten fused salt and petroleum, and the heating of petroleum is provided by the partition wall heat exchanger; new partition wall heat exchangers for heat exchange between molten fused salt and petroleum need to be added in the whole system, the utilization rate of the existing heating furnace is 0, and the introduction of the new device will make the investment rate of the whole equipment be high, and in the above technical scheme, the primary distillation column, the atmospheric column and the vacuum column are connected in sequence, the oil at the bottom of the atmospheric column is heated to 360-440 DEG C by the molten fused salt heat exchanger and then enters the vacuum column, the load of the molten fused salt heat exchanger is not reduced, and the heat at the top of the atmospheric column and the vacuum column is not utilized, therefore, the energy consumption is not reduced compared with the prior art.

[0008] Therefore, it is necessary to provide a new technical scheme to solve the above technical problems. SUMMARY

[0009] The present application provides a petroleum atmospheric and vacuum distillation device, which comprises a primary distillation column, an atmospheric column and a vacuum column connected in sequence, a condenser for the atmospheric column and a condenser for the vacuum column are respectively connected to the top of the atmospheric column and the vacuum column,

[0010] A negative pressure column is arranged between the primary distillation column and the atmospheric column, a reboiler for the negative pressure column is connected to the lower part of the negative pressure column, the hot side outlet of the reboiler for the negative pressure column is connected to the condenser for the atmospheric column and the condenser for the vacuum column through heat exchange pipelines, and the condenser for the atmospheric column and the condenser for the vacuum column are respectively connected to the inlet of the reboiler for the negative pressure column through heat supply pipelines.

[0011] As a preferred scheme, a heat pump for the atmospheric column is arranged on the heat supply pipeline at the top of the condenser for the atmospheric column, and a heat pump for the vacuum column is arranged on the heat supply pipeline at the top of the condenser for the vacuum column.

[0012] As a preferred scheme, a condenser for the negative pressure column is connected to the top of the negative pressure column, the condenser for the negative pressure column is connected to a backflow device for the negative pressure column, the condenser for the negative pressure column is connected to a first heat exchange pipeline, and the first heat exchange pipeline is connected to a second heat exchange pipeline.

[0013] As a preferred scheme, a backflow device for the primary distillation column is connected to the top of the primary distillation column, the backflow device for the primary distillation column comprises a top pipeline arranged at the top of the primary distillation column, a condenser for the primary column, a condenser, a backflow tank for the primary column and a backflow pump for the primary column are arranged in sequence on the top pipeline of the primary distillation column, and the top pipeline of the primary distillation column after the backflow pump for the primary column is connected to the primary distillation column through a backflow pipeline.

[0014] As a preferred scheme, a heat exchange condenser is arranged on one side of the negative pressure column, the heat exchange condenser is connected to the condenser for the primary column through a first heat exchange pipeline for the primary distillation column, a heat pump for the primary column is arranged on the first heat exchange pipeline for the primary distillation column, the heat exchange condenser is also connected to the condenser for the primary column through a second heat exchange pipeline for the primary distillation column, and a pump body for the primary column is arranged on the second heat exchange pipeline for the primary distillation column.

[0015] As a preferred solution, the negative pressure column reflux device comprises a negative pressure column reflux tank, the negative pressure column reflux tank is connected with the top of the negative pressure column through a negative pressure column top production pipeline, a negative pressure column condenser is arranged on the negative pressure column top production pipeline, the bottom of the negative pressure column reflux tank is connected with the middle upper part of the negative pressure column through a negative pressure column reflux pipeline, and the bottom of the negative pressure column reflux tank is also provided with a component production pipeline.

[0016] As a preferred solution, a negative pressure column heat pump is arranged on the production pipeline.

[0017] As a preferred solution, one side of the negative pressure column is connected with a negative pressure stripping column through a negative pressure column side line, steam is introduced into one side of the negative pressure stripping column, the top of the negative pressure stripping column is connected with one side of the negative pressure column through a negative pressure stripping top pipeline, and the bottom of the negative pressure stripping column is provided with a component production pipeline I.

[0018] As a preferred solution, the top of the atmospheric column is connected with an atmospheric column reflux device, the atmospheric column reflux device comprises an atmospheric column reflux tank, the atmospheric column reflux tank is connected with the top of the atmospheric column through an atmospheric column top production pipeline, an atmospheric column condensing device is connected with the atmospheric column top production pipeline, the bottom of the atmospheric column reflux tank is connected with an atmospheric column material production pipeline, the atmospheric column material production pipeline is connected with an atmospheric column reflux pipeline, and the atmospheric column reflux pipeline is connected with the middle upper part of the atmospheric column.

[0019] As a preferred solution, the atmospheric column condensing device adopts an atmospheric column condenser, the atmospheric column condenser is connected with a negative pressure column reboiler through a heat supply pipeline, an atmospheric column heat pump is arranged on the heat supply pipeline, and the hot side outlet of the negative pressure column reboiler is connected with the atmospheric column condenser through the heat exchange pipeline.

[0020] As a preferred solution, the atmospheric column condensing device comprises an atmospheric column condenser and an air cooler arranged in parallel, valves are arranged in front of the atmospheric column condenser and the air cooler respectively, the atmospheric column condenser is connected with a negative pressure column reboiler through a heat supply pipeline, an atmospheric column heat pump is arranged on the heat supply pipeline, and the hot side outlet of the negative pressure column reboiler is connected with the atmospheric column condenser through the heat exchange pipeline.

[0021] As a preferred solution, a secondary atmospheric column condenser is arranged at the rear part of the atmospheric column condenser, a circulating loop is connected with the secondary atmospheric column condenser, a heat pump is arranged on the circulating loop, and a heat exchanger is arranged at the rear part of the heat pump on the circulating loop.

[0022] As a preferred solution, the atmospheric tower is connected with the atmospheric stripping tower through an atmospheric tower side line, the atmospheric stripping tower is connected with the atmospheric tower through an atmospheric tower reflux side line, the atmospheric stripping tower is connected with steam, and one side of the atmospheric stripping tower is connected with an atmospheric stripping tower production pipeline.

[0023] As a preferred solution, the atmospheric tower side line, the atmospheric tower reflux side line, and the atmospheric stripping tower production pipeline each comprise three.

[0024] As a preferred solution, the vacuum tower top is provided with a vacuumizing device, the vacuumizing device comprises a vacuum tower buffer tank, the top of the vacuum tower buffer tank is connected with the top of the vacuum tower through a vacuum tower top production pipeline, a vacuum tower condenser is arranged on the vacuum tower top production pipeline, and the top and the bottom of the vacuum tower buffer tank are respectively connected with a vacuumizing pipeline and a vacuum tower buffer tank production pipeline.

[0025] As a preferred solution, the vacuum tower condenser is connected with a negative pressure tower reboiler through a heat supply pipeline, a vacuum tower heat pump is arranged on the heat supply pipeline, and the hot side outlet of the negative pressure tower reboiler is connected with the vacuum tower condenser through a heat exchange pipeline.

[0026] As a preferred solution, one side of the vacuum tower is respectively connected with a vacuum one side line, a vacuum two side line, and a vacuum three side line, wherein the vacuum one side line and the vacuum two side line are respectively connected with the vacuum tower through a vacuum tower reflux pipeline.

[0027] As a preferred solution, the bottom of the vacuum tower is connected with a vacuum residue production pipeline.

[0028] As a preferred solution, a reflux tank and a delivery pump are arranged on the heat exchange pipeline.

[0029] The application provides a petroleum atmospheric and vacuum distillation process, which comprises an initial distillation tower, a negative pressure tower, an atmospheric tower, and a vacuum tower connected in sequence, heat of the top of the atmospheric tower and the vacuum tower is used to heat liquid phase flowing out of a hot side outlet of a negative pressure tower reboiler, then the liquid phase is pressurized to provide heat for the negative pressure tower reboiler, and after heat exchange in the negative pressure tower reboiler, liquid water is condensed and introduced into an atmospheric tower condenser and a vacuum tower condenser for recycling.

[0030] As a preferred solution, steam pressurized at the top of the initial distillation tower is introduced into a heat exchange condenser for heat exchange, condensed into liquid water, and introduced into an initial tower condenser at the top of the initial distillation tower for recycling, and the heat exchange condenser provides heat for middle section reflux of the negative pressure tower.

[0031] As a preferred solution, liquid water introduced from the hot side outlet of the negative pressure tower reboiler is heated in a negative pressure tower condenser by using heat of the top of the negative pressure tower and then introduced for use.

[0032] As a preferred solution, the atmospheric column further comprises a two-stage heat pump upgrading process, the liquid phase in the circulating loop is heated in the two-stage atmospheric column condenser by using the heat of the overhead of the atmospheric column, and the heated liquid phase is compressed and heated, and then the heat of the compressed and heated liquid phase is absorbed by the heat exchanger for use.

[0033] The present application has the following advantages:

[0034] 1. A negative pressure column is added in front of the atmospheric column, which increases the processing capacity of the atmospheric column, reduces the load of the atmospheric column or the atmospheric column heating furnace, improves the fractionation precision, effectively improves the utilization rate of crude oil, reduces the energy loss, increases the pull-out rate of the device, proposes a new way of atmospheric column capacity expansion and energy saving, and increases the economic benefit of the device; and by reducing the load of the atmospheric column or the atmospheric column heating furnace, the scaling and pressure drop of the crude oil in the heat exchange network are reduced, the heat exchange efficiency is improved, the product variety is increased, the influence of the crude oil with water on the atmospheric column is alleviated, and the operation of the super light oil is adapted;

[0035] 2. The overhead steam of the primary distillation column, the negative pressure column, the atmospheric column and the vacuum column is used for heat cascade utilization, the energy of the overhead steam of the primary distillation column is upgraded by the heat pump, and then the energy enters the middle section reflux of the negative pressure column to consume the energy and condenses into liquid water, which is introduced into the primary distillation column condenser at the top of the primary distillation column by a pump for recycling, the overhead steam of the atmospheric column and the vacuum column is recycled, and the heat pump refrigerant is used for heat absorption, i.e. the heat pump is used to upgrade the gaseous medium, the steam is heated and pressurized, and then the saturated steam is introduced into the reboiler of the negative pressure column to consume the energy and condenses into liquid water, which is introduced into the atmospheric column condenser and the vacuum column condenser by a pump for recycling after being heated; the overhead steam of the negative pressure column is introduced for utilization, and the low-temperature heat of the column top is reasonably utilized; further, the energy consumption is reduced, the heat is recycled and reused, and the fractionation efficiency is improved;

[0036] 3. The atmospheric column and the stripping column are heat exchanged, the load of the vacuum heating furnace is reduced, the fractionation precision is improved, the utilization rate of the crude oil is effectively improved, and the energy loss is reduced;

[0037] 4. The original equipment is modified, new equipment is not introduced, only the existing equipment is increased, the equipment is old and useful, and the investment is relatively small;

[0038] 5. The processing load of the atmospheric and vacuum system is reasonably distributed, the heat is integrated, the heat exchange process is optimized, the energy consumption is reduced, and the requirements of large-scale device and diversified petroleum processing are met;

[0039] 6. The circulating water is saved, and the heat of the discharged air is reduced;

[0040] 7. This invention changes the traditional oil refining process, which is conducive to the recovery of waste heat energy of the equipment and facilitates production operation. Due to the good mass transfer effect, it can effectively improve the extraction rate, reduce energy loss, reduce heat loss, and save investment. Overall, it has the functions of reducing energy consumption, recovering and reusing heat, and improving fractionation efficiency. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of this application;

[0042] 1. Primary distillation column; 2. Negative pressure column; 3. Atmospheric pressure column; 4. Vacuum distillation column;

[0043] 5. Bottom pipeline of the primary distillation column; 6. Primary distillation column transfer pump; 7. Primary distillation column feed condenser;

[0044] 8. Bottom pipeline of the negative pressure tower; 9. Atmospheric pressure heating furnace; 10. Bottom pipeline of the atmospheric pressure tower;

[0045] 11. Vacuum-reducing furnace; 12. Atmospheric pressure tower transfer pump; 13. Vacuum-reducing residue production pipeline;

[0046] 14. Pressure reducing tower conveying pump; 15. Pressure reducing tower conveying condenser; 16. Negative pressure stripping tower;

[0047] 17. Negative pressure tower reboiler; 18. Heating pipeline; 19. Heat exchange pipeline; 20. Primary tower reflux tank;

[0048] 21. Top piping of the primary distillation column; 22. Primary distillation column condenser; 23. Outlet piping; 24. Primary distillation column heat pump;

[0049] 27. Heat exchanger condenser; 28. Primary tower reflux pump; 29. ​​Primary tower reflux pipeline;

[0050] 30. Reflux tank of negative pressure tower; 31. Top outlet pipeline of negative pressure tower; 32. Condenser of negative pressure tower;

[0051] 33. Negative pressure tower reflux pipeline; 34. Negative pressure tower reflux pump; 35. Component extraction pipeline;

[0052] 36. Side pipeline of negative pressure tower; 37. Top pipeline of negative pressure stripping; 38. Component extraction pipeline 1;

[0053] 39. Atmospheric pressure tower reflux tank; 40. Atmospheric pressure tower top outlet pipeline; 41. Atmospheric pressure tower condenser;

[0054] 42. Atmospheric pressure tower material extraction pipeline; 43. Atmospheric pressure tower reflux pipeline; 44. Atmospheric pressure tower reflux pump; 45. Atmospheric pressure tower heat pump; 46. Reflux tank; 47. Transfer pump; 48. Atmospheric pressure stripping tower;

[0055] 49, atmospheric column side draw one; 50, atmospheric column side draw one; 51, atmospheric column side draw three;

[0056] 52, atmospheric column reflux side draw one; 53, atmospheric column reflux side draw two; 54, atmospheric column reflux side draw three;

[0057] 55, atmospheric stripper take away line one; 56, atmospheric stripper take away line two;

[0058] 57, atmospheric stripper take away line three; 58, take away pump; 59, vacuum tower surge drum;

[0059] 60, vacuum tower overhead take away line; 61, vacuum tower condenser; 63, vacuum line;

[0060] 64, vacuum tower surge drum take away line; 65, vacuum tower transfer pump; 66, vacuum tower hotwell;

[0061] 67, vacuum one side draw; 68, vacuum two side draw; 69, vacuum three side draw;

[0062] 70, vacuum column reflux line; 71, electrostatic precipitator; 72, vacuum tower hotwell;

[0063] 73, heat exchange line one; 74, condenser; 75, primary tower heat exchange line one;

[0064] 76, primary tower heat exchange line two; 77, primary tower pump body; 78, air cooler;

[0065] 79, valve; 80, fired heater; 81, secondary atmospheric column condenser; 82, recycle loop;

[0066] 83, hotwell; 84, heat exchanger. DETAILED DESCRIPTION

[0067] The application will be described in greater detail with reference to the following drawings: Figure 1 The specific embodiments of the present application will now be described in detail. It should be appreciated that the detailed description Example One

[0068] The application provides a petroleum atmospheric and vacuum distillation device, which comprises a preliminary distillation tower 1, a negative pressure tower 2, an atmospheric tower 3 and a vacuum tower 4 which are connected in sequence, the bottom of the preliminary distillation tower 1 is connected with the middle upper part of the negative pressure tower 2 through a preliminary distillation tower bottom pipeline 5, a preliminary tower conveying pump 6 and a preliminary tower material conveying condenser 7 are arranged on the preliminary distillation tower bottom pipeline 5 in sequence between the preliminary distillation tower 1 and the negative pressure tower 2, the bottom of the negative pressure tower 2 is connected with the middle lower part of the atmospheric tower 3 through a negative pressure tower bottom pipeline 8, an atmospheric heating furnace 9 is arranged on the negative pressure tower bottom pipeline 8, the atmospheric heating furnace 9 is used for heating the material in the tower kettle of the negative pressure tower 2, the bottom of the atmospheric tower 3 is connected with the vacuum tower 4 through an atmospheric tower bottom pipeline 10, a vacuum heating furnace 11 is arranged on the atmospheric tower bottom pipeline 10, an atmospheric tower conveying pump 12 is arranged on the atmospheric tower bottom pipeline 10 in the front part of the vacuum heating furnace 11, the bottom of the vacuum tower 4 is connected with a vacuum residue oil extraction pipeline 13, a vacuum tower conveying pump 14 and a vacuum tower material conveying condenser 15 are arranged on the vacuum residue oil extraction pipeline 13, the lower part of the negative pressure tower 2 is connected with a negative pressure tower reboiler 17, heat is provided for the negative pressure tower reboiler 17 by steam and the like when starting, the energy source of the negative pressure tower 2 is the negative pressure tower reboiler 17, the negative pressure tower reboiler 17 adopts a circulating forced falling film reboiler or a forced circulation rising film reboiler, wherein the falling film reboiler has the advantages of low surface temperature, short material residence time and low process side line pressure, in order to further prevent coking and optimize production, vacuum rectification operation is adopted from the process technology, the boiling point of the material is reduced, and the occurrence of material thermal degradation is reduced; the top parts of the atmospheric tower 3 and the vacuum tower 4 are respectively connected with an atmospheric tower condenser 41 and a vacuum tower condenser 61, the hot side outlet of the negative pressure tower reboiler 17 is connected with the atmospheric tower condenser 41 and the vacuum tower condenser 61 through heat exchange pipelines 19, the atmospheric tower condenser 41 and the vacuum tower condenser 61 are respectively connected with the inlet of the negative pressure tower reboiler 17 through heat supply pipelines 18; the gas phase at the top of the atmospheric tower 3 and the vacuum tower 4 is condensed through the atmospheric tower condenser 41 and the vacuum tower condenser 61 respectively after condensation, then the gas phase is subjected to reflux and product extraction, the liquid phase in the negative pressure tower reboiler 17 after heat exchange enters the atmospheric tower condenser 41 and the vacuum tower condenser 61 through the hot side outlet of the negative pressure tower reboiler 17 and the heat exchange pipelines 19 respectively, the material flowing through the atmospheric tower condenser 41 and the vacuum tower condenser 61 in the heat exchange pipelines 19 is heated by using the heat of the gas phase at the top of the atmospheric tower 3 and the vacuum tower 4, then the heated material enters the inlet of the negative pressure tower reboiler 17 and enters the next working cycle.

[0069] Preferably, the atmospheric tower condenser 41 top of the heat supply line 18 is provided with atmospheric tower heat pump 45, the top of the vacuum tower condenser 61 heat supply line 18 is provided with vacuum tower heat pump 66, through the atmospheric tower condenser 41, vacuum tower condenser 61 heated material, through the atmospheric tower heat pump 45, vacuum tower heat pump 66 compression temperature rise, to achieve the negative pressure tower reboiler 17 required heat, do not need to through the external steam to the negative pressure tower reboiler 17 additional heating, improve the atmospheric tower 3 tower top, vacuum tower 4 tower top heat utilization rate, reduce energy consumption.

[0070] The embodiment increases a negative pressure tower 2 in front of the atmospheric tower 3, changes the traditional three tower atmospheric vacuum distillation process into a four tower four stage distillation process, reduces the load of the atmospheric tower 3 or the atmospheric heating furnace 9, simultaneously reduces the fouling and pressure drop of the crude oil in the heat exchange network, improves the heat exchange efficiency, can increase the product variety, relieves the influence of the crude oil with water on the atmospheric tower, adapts to the operation of the super light oil, and has the effects of reducing energy consumption, heat recovery and reuse, and improving the distillation efficiency; the application can recycle the heat of the tower top steam of the atmospheric tower 3 and the vacuum tower 4, and heat is taken by different heat pump refrigeration working media, such as water when the temperature is high, pressure increase safety; when the temperature is low, heat is taken by methanol, R134A and the like, that is, the vaporized medium is upgraded by the heat pump, the heat exchange is performed first, then the pressure is increased, the steam reaches a certain pressure, is saturated, and then is introduced into the negative pressure tower reboiler 17 of the negative pressure tower 2 to consume the energy, and is condensed into liquid water and introduced into the atmospheric tower condenser 41 and the vacuum tower condenser 61 through a pump for repeated use; thus, the effects of reducing energy consumption, heat recovery and reuse, and improving the distillation efficiency are further achieved. Embodiment two

[0071] The embodiment specifically describes the preliminary distillation tower 1, and specifically:

[0072] The top of the preliminary distillation tower 1 is connected with a preliminary distillation tower reflux device, the preliminary distillation tower reflux device comprises a preliminary distillation tower top pipeline 21 arranged at the top of the preliminary distillation tower 1, the preliminary distillation tower top pipeline 21 is sequentially provided with a preliminary tower condenser 22, a condenser 74, a preliminary tower reflux tank 20 and a preliminary tower reflux pump 28, the preliminary distillation tower top pipeline 21 is respectively connected with a light gasoline extraction pipeline 85 and a preliminary tower reflux pipeline 29, and the preliminary tower reflux pipeline 29 is connected with the upper middle part of the preliminary distillation tower 1.

[0073] The gas phase at the top of the preliminary distillation tower 1 is condensed through the preliminary tower condenser 22 and the condenser 74 and then enters the preliminary tower reflux tank 20, part of the liquid phase in the preliminary tower reflux tank is refluxed to the preliminary distillation tower 1 through the preliminary tower reflux pipeline 29, and part of the liquid phase is extracted as light gasoline through the light gasoline extraction pipeline 85. Embodiment three

[0074] The embodiment specifically describes the negative pressure tower 2, and specifically:

[0075] The top of the negative pressure column 2 is provided with a negative pressure column reflux device, which comprises a negative pressure column reflux tank 30 connected with the top of the negative pressure column 2 through a negative pressure column top production pipeline 31, the negative pressure column top production pipeline 31 is provided with a negative pressure column condenser 32, the bottom of the negative pressure column reflux tank 30 is connected with the middle upper part of the negative pressure column 2 through a negative pressure column reflux pipeline 33, the negative pressure column reflux pipeline 33 is provided with a negative pressure column reflux pump 34, the bottom of the negative pressure column reflux tank 30 is further provided with component production pipelines 35, preferably including naphtha production pipelines and aqueous solution production pipelines, respectively used for producing naphtha and aqueous solution, the negative pressure column condenser 32 is connected with a production pipeline 23, the production pipeline 23 is provided with a negative pressure column heat pump 72, the column top steam of the negative pressure column 2 is led out for use, and the low-temperature heat of the column top is reasonably utilized, for example, the heat of the steam at 60-70 degrees is upgraded and pressurized into hot water at 70-80 degrees through the negative pressure column heat pump 72, which can be used for heating and heat preservation; the gas phase at the top of the negative pressure column 2 enters the negative pressure column reflux tank 30 after being condensed by the negative pressure column condenser 32, and part of the liquid phase of the negative pressure column reflux tank 30 is refluxed to the negative pressure column 2 through the negative pressure column reflux pipeline 33, and part of the liquid phase of the negative pressure column reflux tank 30 is produced as naphtha and / or aqueous solution through the component production pipelines 35.

[0076] Preferably, in order to further utilize the heat of the column top of the negative pressure column 2, the negative pressure column condenser 32 is connected with a heat exchange pipeline I 73, the heat exchange pipeline I 73 is connected with a heat exchange pipeline 19; the gas phase at the top of the negative pressure column 2 enters the negative pressure column reflux tank 30 after being condensed by the negative pressure column condenser 32, part of the liquid phase of the negative pressure column reflux tank 30 is refluxed to the negative pressure column 2 through the negative pressure column reflux pipeline 33, and part of the liquid phase of the negative pressure column reflux tank 30 is produced as naphtha and / or aqueous solution through the component production pipelines 35; the liquid phase after heat exchange in the negative pressure column reboiler 17 enters the negative pressure column condenser 32 through the hot side outlet of the negative pressure column reboiler 17, the heat exchange pipeline 19 and the heat exchange pipeline I 73, the heat of the gas phase at the column top of the negative pressure column 2 is utilized to heat the material flowing through the negative pressure column condenser 32 in the heat exchange pipeline I 73, and the liquid phase after heating is compressed and heated by the negative pressure column heat pump 72, and the column top steam of the negative pressure column 2 is led out for use through the production pipeline 23, and the low-temperature heat of the column top is reasonably utilized.

[0077] Further, in order to ensure the product quality of the negative pressure column 2, improve the product flash point, and reduce the light component content, one side of the negative pressure column 2 is connected with the negative pressure stripping column 16 through a negative pressure column side line 36, steam is introduced into one side of the negative pressure stripping column 16 as the power of the negative pressure stripping column 16, the top of the negative pressure stripping column 16 is connected with one side of the negative pressure column 2 through a negative pressure stripping top line 37, the bottom of the negative pressure stripping column 16 is provided with a component extraction line one 38, part of the material of the negative pressure column 2 enters the negative pressure stripping column 16 for stripping through the negative pressure column side line 36, the gas phase at the top of the negative pressure stripping column 16 enters the negative pressure column 2 for continuous distillation through the negative pressure stripping top line 37, and the component extraction line one 38 at the bottom of the negative pressure stripping column 16 extracts kerosene.

[0078] Further, in order to fully utilize the heat of the gas phase at the top of the primary distillation column 1, one side of the negative pressure column 2 is provided with a heat exchange condenser 27, the primary distillation column condenser 27 is connected with the primary column condenser 22 through a primary distillation column heat exchange line one 75, the primary distillation column heat exchange line one 75 is provided with a primary column heat pump 24, the heat exchange condenser 27 is also connected with the primary column condenser 22 through a primary distillation column heat exchange line two 76, and the primary distillation column heat exchange line two 76 is provided with a primary column pump body 77; the gas phase at the top of the primary distillation column 1 is condensed after passing through the primary column condenser 22 and the condenser 74, and then enters the primary column reflux tank 20, part of the liquid phase in the primary column reflux tank is refluxed to the primary distillation column 1 through a primary column reflux line 29, and part of the liquid phase is extracted as light gasoline through a light gasoline extraction line 85; the liquid phase at the output end of the heat exchange condenser 27 is transported to the primary column condenser 22 for heat exchange through the primary column pump body 77, the heat of the gas phase at the top of the primary distillation column 1 is utilized to heat the material flowing through the primary column condenser 22 in the primary distillation column heat exchange line two 76, the heated liquid phase is further compressed and heated by the primary column heat pump 24, and then enters the inlet of the heat exchange condenser 27 to provide heat for the middle section reflux of the negative pressure column 2. Example Four

[0079] In this embodiment, the atmospheric column 3 is specifically described as follows:

[0080] The top of the atmospheric column 3 is connected with an atmospheric column reflux device, which comprises an atmospheric column reflux tank 39 connected with the top of the atmospheric column 3 through an atmospheric column top extraction pipeline 40, and an atmospheric column condensing device is connected with the atmospheric column top extraction pipeline 40; the bottom of the atmospheric column reflux tank 39 is connected with an atmospheric column material extraction pipeline 42, and an atmospheric column reflux pipeline 43 is connected with the atmospheric column material extraction pipeline 42; the atmospheric column reflux pump 44 is arranged on the atmospheric column material extraction pipeline 42, and the atmospheric column reflux pipeline 43 is connected with the atmospheric column material extraction pipeline 42 behind the atmospheric column reflux pump 44; the gas phase extracted from the top of the atmospheric column 3 enters the atmospheric column reflux tank 39 after being cooled by the atmospheric column condensing device, and part of the liquid phase in the atmospheric column reflux tank 39 is refluxed to the atmospheric column 3 through the atmospheric column reflux pipeline 43, and part of the liquid phase is extracted as gasoline through the atmospheric column material extraction pipeline 42.

[0081] Preferably, the atmospheric column condensing device adopts an atmospheric column condenser 41 connected with the negative pressure column reboiler 17 through a heat supply pipeline 18, and an atmospheric column heat pump 45 is arranged on the heat supply pipeline 18; the hot side outlet of the negative pressure column reboiler 17 is connected with the atmospheric column condenser 41 through a heat exchange pipeline 19, and a reflux tank 46 and a delivery pump 47 are arranged on the heat exchange pipeline 19; the gas phase at the top of the atmospheric column 3 enters the atmospheric column reflux tank 39 after being cooled by the atmospheric column condenser 41, part of the liquid phase in the atmospheric column reflux tank 39 is refluxed to the atmospheric column 3 through the atmospheric column reflux pipeline 43, and part of the liquid phase is extracted as gasoline through the atmospheric column material extraction pipeline 42; the liquid phase in the negative pressure column reboiler 17 after heat exchange enters the atmospheric column condenser 41 through the hot side outlet of the negative pressure column reboiler 17 and the heat exchange pipeline 19, and the heat exchange pipeline 19 is heated by the gas phase at the top of the atmospheric column 3; the liquid phase after heating is compressed and heated by the atmospheric column heat pump 45, and then enters the inlet of the negative pressure column reboiler 17 to supply heat to the negative pressure column reboiler 17 and enter the next working cycle.

[0082] The embodiment also provides another form of atmospheric column condensing device, which comprises an atmospheric column condenser 41 and an air cooler 78 arranged in parallel, the front parts of the atmospheric column condenser 41 and the air cooler 78 are respectively provided with a valve 79, the atmospheric column condenser 41 is connected with a negative pressure column reboiler 17 through a heat supply pipeline 18, the heat supply pipeline 18 is provided with an atmospheric column heat pump 45, the hot side outlet of the negative pressure column reboiler 17 is connected with the atmospheric column condenser 41 through the heat exchange pipeline 19, and the heat exchange pipeline 19 is provided with a reflux tank 46 and a delivery pump 47. The atmospheric column condensing device of this form uses the heat of the overhead of the atmospheric column 3 to transfer the water cooling of the atmospheric column condenser 41 and the air cooling of the air cooler 78, the gas phase of the overhead of the atmospheric column 3 is condensed by the atmospheric column condenser 41 and / or the air cooler 78, and then enters the atmospheric column reflux tank 39. A part of the liquid phase of the atmospheric column reflux tank 39 is refluxed to the atmospheric column 3 through an atmospheric column reflux pipeline 43, and a part of the liquid phase is extracted as gasoline through an atmospheric column material extraction pipeline 42. The liquid phase after heat exchange in the negative pressure column reboiler 17 enters the atmospheric column condenser 41 through the hot side outlet of the negative pressure column reboiler 17 and the heat exchange pipeline 19, and the heat of the gas phase of the overhead of the atmospheric column 3 is used to heat the material flowing through the atmospheric column condenser 41 in the heat exchange pipeline 19. The liquid phase after heating is compressed and heated by the atmospheric column heat pump 45, enters the inlet of the negative pressure column reboiler 17, supplies heat to the negative pressure column reboiler 17, and enters the next working cycle. This scheme fully utilizes the heat of the overhead of the atmospheric column 3, saves circulating water, and reduces the heat of the discharged gas.

[0083] More preferably, the above two forms of atmospheric column condensing device are provided with a secondary atmospheric column condenser 81 at the rear part of the atmospheric column condenser 41, the secondary atmospheric column condenser 81 is connected with a circulating loop 82, the circulating loop 82 is provided with a heat pump 83, and the rear part of the heat pump 83 is provided with a heat exchanger 84 on the circulating loop 82. In this embodiment, there are two different heat pump upgrades. The first level is the gas phase condensed by the atmospheric column condenser 41, which is used to heat the liquid phase flowing out of the hot side outlet of the negative pressure column reboiler 17, and then is upgraded to high-pressure steam by the compressor of the atmospheric column heat pump 45, and enters the negative pressure column reboiler 17 to provide heat. The second level is the gas phase condensed by the secondary atmospheric column condenser 81, which is used to heat the liquid phase in the circulating loop 82, and then is compressed and heated by the heat pump 83, and the heat after compression of the heat pump 83 is absorbed by the heat exchanger 84 to other processes. For example, the first level is 120℃ reduced to 70℃, and this part of energy is upgraded to high-pressure steam by the compressor of the atmospheric column heat pump 45. The second level is 70℃ reduced to 40℃, and the heat is released by condensation, and the energy is recycled by the heat pump 83 and the heat exchanger 84.

[0084] Further, to ensure the product quality and fractionation precision of the atmospheric column 3, to ensure the product quality and flash point, to reduce the partial pressure of light components, and to improve the extraction rate of crude oil, the atmospheric column 3 is connected with the atmospheric stripping column 48 through an atmospheric column side line, the atmospheric stripping column 48 is connected with the atmospheric column 3 through an atmospheric column backflow side line, the atmospheric stripping column 48 is connected with a steam inlet, the steam provides power for the atmospheric stripping column 48, and one side of the atmospheric stripping column 48 is connected with an atmospheric stripping column production pipeline, which produces corresponding products. In this embodiment, the atmospheric column is connected with the atmospheric stripping column 48 through an atmospheric column side line one 49, an atmospheric column side line two 50, and an atmospheric column side line three 51, the atmospheric stripping column 48 is connected with the atmospheric column 3 through an atmospheric column backflow side line one 52, an atmospheric column backflow side line two 53, and an atmospheric column backflow side line three 54, one side of the atmospheric stripping column 48 is connected with an atmospheric stripping column production pipeline one 55, an atmospheric stripping column production pipeline two 56, and an atmospheric stripping column production pipeline three 57, and each of the atmospheric stripping column production pipeline one 55, the atmospheric stripping column production pipeline two 56, and the atmospheric stripping column production pipeline three 57 is provided with a production pump 58, the atmospheric stripping column production pipeline one 55 produces kerosene, the atmospheric stripping column production pipeline two 56 produces light diesel oil, and the atmospheric stripping column production pipeline three 57 is used to produce heavy diesel oil.

[0085] The atmospheric column 3 is provided with three side line products and three middle section backflows, so as to uniformly distribute the gas-liquid load of the whole column and facilitate the optimization of the heat exchange network of the whole device, to recover the excess heat of the whole column and use it to heat the crude oil and generate steam, and to ensure the product quality and fractionation precision, the side line products are provided with the atmospheric stripping column 48. Embodiment five

[0086] This embodiment describes the vacuum column 4, in particular:

[0087] The vacuum column 4 is provided with a vacuum extraction device at the top, the vacuum extraction device includes a vacuum column buffer tank 59, the top of the vacuum column buffer tank 59 is connected with the top of the vacuum column 4 through a vacuum column top production pipeline 60, the vacuum column top production pipeline 60 is provided with a vacuum column condenser 61, the top and the bottom of the vacuum column buffer tank 59 are respectively connected with a vacuum extraction pipeline 63 and a vacuum column buffer tank production pipeline 64, and the vacuum column buffer tank production pipeline 64 is provided with a vacuum column delivery pump 65; the vacuum extraction device extracts the overhead gas of the vacuum column 4 and ensures the vacuum degree of the overhead; in particular, the overhead gas phase of the vacuum column 4 enters the vacuum column buffer tank 59 after being cooled by the vacuum column condenser 61, the top of the vacuum column buffer tank 59 is extracted in vacuum, and the bottom of the vacuum column buffer tank 59 produces top oil through the vacuum column buffer tank production pipeline 64.

[0088] Preferably, the reduced pressure column condenser 61 is connected with the negative pressure column reboiler 17 through a heat supply line 18, and a reduced pressure column heat pump 66 is arranged on the heat supply line 18. The overhead gas phase of the reduced pressure column 4 enters a reduced pressure column buffer tank 59 after being cooled by the reduced pressure column condenser 61. The top of the reduced pressure column buffer tank 59 is vacuumized, and the bottom of the reduced pressure column buffer tank 59 discharges the overhead oil through a reduced pressure column buffer tank discharge line 64. The liquid phase after heat exchange in the negative pressure column reboiler 17 enters the reduced pressure column condenser 61 through the hot side outlet of the negative pressure column reboiler 17 and a heat exchange line 19 to exchange heat. The heat of the overhead gas phase of the reduced pressure column 4 is used to heat the material flowing through the reduced pressure column condenser 61 in the heat exchange line 19. The heated liquid phase is compressed and heated by the reduced pressure column heat pump 66 and then enters the inlet of the negative pressure column reboiler 17 to supply heat to the negative pressure column reboiler 17 for the next working cycle. This scheme fully utilizes the heat of the overhead gas phase of the reduced pressure column 4, saves circulating water, and reduces the heat of the discharged gas.

[0089] The reduced pressure column 4 is connected with a reduced one side line 67, a reduced two side line 68 and a reduced three side line 69 on one side. The reduced one side line 67, the reduced two side line 68 and the reduced three side line 69 are used to discharge different materials according to different crude oils, such as lubricating oil type, different grades of lubricating oil, fuel type, and different grades of wax oil. The reduced one side line 67 and the reduced two side line 68 are connected with the reduced pressure column 4 through a reduced pressure column reflux line 70. The bottom of the reduced pressure column 4 is connected with a reduced pressure residue discharge line 13. Embodiment six

[0090] The embodiment provides a petroleum atmospheric and vacuum distillation process, which comprises an initial distillation column 1, a negative pressure column 2, an atmospheric column 3 and a reduced pressure column 4 connected in sequence. The heat of the overhead of the atmospheric column 3 and the reduced pressure column 4 is used to heat the liquid phase flowing out of the hot side outlet of the negative pressure column reboiler 17, and the heated liquid phase provides heat for the negative pressure column reboiler 17 after being pressurized. The liquid phase after heat exchange in the negative pressure column reboiler 17 is condensed into liquid water and introduced into the atmospheric column condenser 41 and the reduced pressure column condenser 61 for repeated use. The gas phase of the initial distillation column 1 is partially discharged as products and partially refluxed into the initial distillation column 1 after being condensed. The gas phase of the negative pressure column 2 is partially discharged as products and partially refluxed into the negative pressure column 2 after being condensed. The gas phase of the atmospheric column 3 is partially discharged as products and partially refluxed into the atmospheric column 3 after being condensed. The side line of the atmospheric column 3 discharges products. The gas phase of the reduced pressure column 4 is discharged as products after being condensed. The side line of the reduced pressure column 4 discharges products. The reduced pressure residue is discharged from the bottom of the reduced pressure column 4.

[0091] Preferably, the overhead vapor of the primary distillation column 1 is pressurized and then enters the heat exchange condenser 27 to exchange heat and condense into liquid water, which is introduced into the primary column condenser 22 at the top of the primary distillation column 1 for recycling, and the heat exchange condenser 27 provides heat for the mid-stage reflux of the negative pressure column 2; preferably, the liquid water introduced from the hot side outlet of the negative pressure column reboiler 17 is heated in the negative pressure column condenser 32 using the heat at the top of the negative pressure column 2 and then recovered.

[0092] Preferably, the atmospheric column 3 further includes a secondary heat pump upgrading process, the liquid phase in the circulation loop 82 passes through the secondary atmospheric column condenser 81, and the heat at the top of the atmospheric column 3 is used to heat the liquid phase in the circulation loop 82 in the secondary atmospheric column condenser 81, and the heated liquid phase is compressed and heated, and then the heat of the compressed and heated liquid phase is absorbed by the heat exchanger 84 for use; the primary heat pump upgrading process of the atmospheric column 3, as described above, the heat at the top of the atmospheric column 3 is used to heat the liquid phase flowing out of the hot side outlet of the negative pressure column reboiler 17, which is pressurized to provide heat for the negative pressure column reboiler 17, and after heat exchange in the negative pressure column reboiler 17, the liquid water is condensed and introduced into the atmospheric column condenser 41 for recycling.

[0093] The working principle of the present application is as follows: crude oil is fed into the electric desalting tank 71 for desalting and dewatering, and the feeding temperature is 360-370 DEG C; the oil after desalting and dewatering is heated by the heating furnace 80 and then fed into the primary distillation tower 1, the top of which is provided with a tower top reflux, and the top gas and light gasoline of the primary distillation tower 1 are extracted, the bottom oil of the primary distillation tower 1 is heated by heat exchange and then fed into the negative pressure tower 2, the top gas of the negative pressure tower 2 is extracted, and naphtha and / or water are collected, the side line material of the negative pressure tower 2 is stripped by the negative pressure stripping tower 16, and the component kerosene is collected, the negative pressure tower reboiler 17 provides heat for the negative pressure tower 2, the bottom oil of the negative pressure tower 2 is heated by the atmospheric heating furnace 9 and then fed into the atmospheric tower 3, the top gas and gasoline of the atmospheric tower 3 are extracted, the atmospheric tower 3 is provided with three side lines, and the atmospheric stripping tower extraction pipeline one 55, the atmospheric stripping tower extraction pipeline two 56 and the atmospheric stripping tower extraction pipeline three 57 are stripped by the stripping steam in the atmospheric stripping tower 48, and kerosene, light diesel and heavy diesel are collected respectively; the bottom oil of the atmospheric tower 3 is gradually heated by the vacuum heating furnace 11 and then fed into the vacuum tower 4, the top of the vacuum tower 4 is provided with a vacuum extraction device, the top gas of the vacuum tower 4 is extracted, and the vacuum degree of the top of the vacuum tower 4 is maintained, and the top of the vacuum tower 4 collects the top oil; wherein the gas phase of the top of the primary distillation tower 1 is condensed by the primary tower condenser 22 and the condenser 74 and then enters the primary reflux tank 20, part of the liquid phase in the primary reflux tank is refluxed to the primary distillation tower 1 through the primary reflux pipeline 29, and part of the liquid phase is collected as light gasoline through the light gasoline extraction pipeline 85; the liquid phase at the output end of the heat exchange condenser 27 is transported to the primary tower condenser 22 by the primary tower pump body 77 for heat exchange, the heat of the gas phase of the top of the primary distillation tower 1 is used to heat the material in the primary tower condenser 22 in the primary distillation tower heat exchange pipeline two 76, the heated liquid phase is further compressed and heated by the primary tower heat pump 24, enters the inlet of the heat exchange condenser 27, and provides heat for the middle section reflux of the negative pressure tower 2; the gas phase at the top of the negative pressure tower 2 is condensed by the negative pressure tower condenser 32 and then enters the negative pressure reflux tank 30, part of the liquid phase in the negative pressure reflux tank 30 is refluxed to the negative pressure tower 2 through the negative pressure reflux pipeline 33, and part of the liquid phase is collected as naphtha and / or water solution through the component extraction pipeline 35, the liquid phase after heat exchange in the negative pressure tower reboiler 17 enters the negative pressure tower condenser 32 through the hot side outlet of the negative pressure tower reboiler 17, the heat exchange pipeline 19 and the heat exchange pipeline one 73, the heat of the gas phase of the top of the negative pressure tower 2 is used to heat the material in the negative pressure tower condenser 32 in the heat exchange pipeline one 73, the heated liquid phase is compressed and heated by the negative pressure tower heat pump 72, the top steam of the negative pressure tower 2 is extracted by the extraction pipeline 23 for use, and the low-temperature heat of the top is reasonably utilized.The gas phase at the top of the atmospheric column 3 is cooled by the atmospheric column condensing device and then enters the atmospheric column reflux tank 39. The liquid phase in the atmospheric column reflux tank 39 is partially refluxed to the atmospheric column 3 through the atmospheric column reflux pipeline 43 and is partially tapped as gasoline through the atmospheric column material tapping pipeline 42. The liquid phase after heat exchange in the negative pressure column reboiler 17 enters the atmospheric column condenser 41 through the hot side outlet of the negative pressure column reboiler 17 and the heat exchange pipeline 19. The heat of the gas phase at the top of the atmospheric column 3 is used to heat the material flowing through the atmospheric column condenser 41 in the heat exchange pipeline 19. The heated liquid phase is compressed and heated by the atmospheric column heat pump 45 and then enters the inlet of the negative pressure column reboiler 17 to heat the negative pressure column reboiler 17 and enters the next working cycle. The gas phase at the top of the vacuum column 4 is cooled by the vacuum column condenser 61 and then enters the vacuum column buffer tank 59. The top of the vacuum column buffer tank 59 is vacuumized and the vacuum column buffer tank 59 is tapped for reduced top oil through the vacuum column buffer tank tapping pipeline 64. The liquid phase after heat exchange in the negative pressure column reboiler 17 enters the vacuum column condenser 61 through the hot side outlet of the negative pressure column reboiler 17 and the heat exchange pipeline 19. The heat of the gas phase at the top of the vacuum column 4 is used to heat the material flowing through the vacuum column condenser 61 in the heat exchange pipeline 19. The heated liquid phase is compressed and heated by the vacuum column heat pump 66 and then enters the inlet of the negative pressure column reboiler 17 to heat the negative pressure column reboiler 17 and enters the next working cycle.

[0094] In summary, the present application has the following advantages due to the adoption of the above technical solutions:

[0095] 1. The negative pressure column is added in front of the atmospheric column, which increases the processing capacity of the atmospheric column, reduces the load of the atmospheric column or the atmospheric column heating furnace, improves the fractionation precision, effectively improves the utilization rate of crude oil, reduces the energy loss, increases the pull-out rate of the device, proposes a new way of atmospheric column capacity expansion and energy saving, and increases the economic benefit of the device. By reducing the load of the atmospheric column or the atmospheric column heating furnace, the scaling and pressure drop of the crude oil in the heat exchange network are reduced, the heat exchange efficiency is improved, the product variety is increased, the influence of the crude oil with water on the atmospheric column is alleviated, and the operation of the super light oil is adapted.

[0096] 2. The tower top steam of the primary distillation column, the negative pressure column, the atmospheric column and the vacuum column is subjected to heat cascade utilization, the energy of the tower top steam of the primary distillation column is upgraded by a heat pump, and then the energy enters the middle section reflux of the negative pressure column to consume the energy, is condensed into liquid water, is introduced into the primary distillation column condenser at the top of the primary distillation column by a pump to be recycled, the tower top steam of the atmospheric column and the vacuum column is subjected to heat recovery, different heat pump refrigeration working substances (such as water when the temperature is high, pressure increase safety; methanol, R134A when the temperature is low) are used to take heat, that is, the vaporized medium is upgraded by a heat pump, is subjected to heat exchange and then is subjected to pressure increase, the steam reaches a certain pressure, is saturated, is introduced into the negative pressure column reboiler to consume the energy, is condensed into liquid water and is introduced into the atmospheric column condenser and the vacuum column condenser by a pump to be recycled; the tower top steam of the negative pressure column is introduced to be utilized, the low-temperature heat of the tower top is reasonably utilized, energy consumption is further reduced, heat is recycled, and the effect of improving the fractionation efficiency is achieved.

[0097] 3. The atmospheric column and the stripping column are subjected to heat exchange, the load of the vacuum heating furnace is reduced, the fractionation precision is improved, the utilization rate of crude oil is effectively improved, and energy loss is reduced.

[0098] 4. The original equipment is modified, new equipment does not need to be introduced, only the existing equipment needs to be increased, the equipment has a high utilization rate, and the investment is relatively small.

[0099] 5. The processing load of the atmospheric and vacuum system is reasonably distributed, heat is integrated, the heat exchange process is optimized, energy consumption is reduced, and the requirements of large-scale device and diversified petroleum processing are met.

[0100] 6. Circulating water is saved, and the heat of discharged air is reduced.

[0101] 7. The application changes the traditional oil refining process, is beneficial to the waste heat energy recovery of the device, is convenient for production operation, the mass transfer effect is good, the stripping rate can be effectively improved, energy loss can be reduced, heat loss can be reduced, the effect of saving investment is achieved, and the overall effect of reducing energy consumption, recycling heat, improving the fractionation efficiency is achieved.

[0102] The devices and connection relationships not specifically described above all belong to the prior art, and the application does not make specific elaboration here.

[0103] The preferred mode of the application is described in detail above with reference to the drawings, but the application is not limited to the specific details in the above implementation modes, and various simple modifications can be made to the technical scheme of the application within the technical concept range of the application, and these simple modifications all belong to the protection range of the application.

[0104] It should be further noted that various specific technical features described in the above detailed description are not to be interpreted as essential features of the present application, and that any of these features can be combined in any suitable manner, and that the present application is not limited to the embodiments described in the above detailed description.

[0105] Furthermore, various different embodiments of the present application can be combined with each other, as long as it does not violate the idea of the present application, and the present application should be considered as disclosed.

Claims

1. A petroleum atmospheric and vacuum distillation apparatus comprising a preliminary distillation column (1), an atmospheric column (3), and a vacuum column (4) connected in series, a top portion of the atmospheric column (3) and the vacuum column (4) being connected with an atmospheric column condenser (41) and a vacuum column condenser (61), respectively, characterized in that, The primary distillation column (1), atmospheric column (3) is provided with negative pressure column (2), the lower part of negative pressure column (2) is connected with negative pressure column reboiler (17), the hot side outlet of negative pressure column reboiler (17) is connected with atmospheric column condenser (41), vacuum column condenser (61) through heat exchange pipeline (19) respectively, atmospheric column condenser (41), vacuum column condenser (61) is connected with the inlet of negative pressure column reboiler (17) through heat supply pipeline (18) respectively;The top of negative pressure column (2) is connected with negative pressure column condenser (32), and the negative pressure column condenser (32) is connected with negative pressure reflux device, the negative pressure column condenser (32) is connected with heat exchange pipeline (73), and the heat exchange pipeline (73) is connected with heat exchange pipeline (19);One side of the negative pressure column (2) is provided with heat exchange condenser (27), and the heat exchange condenser (27) is connected with the initial tower condenser (22) through the primary distillation column heat exchange pipeline (75), and the primary distillation column heat exchange pipeline (75) is provided with initial tower heat pump (24), the heat exchange condenser (27) is also connected with the initial tower condenser (22) through the primary distillation column heat exchange pipeline (76), and the primary distillation column heat exchange pipeline (76) is provided with initial tower pump body (77).

2. The petroleum atmospheric and vacuum distillation unit according to claim 1, characterized by The top of the atmospheric column (3) is connected with the atmospheric column reflux device, and the atmospheric column reflux device comprises an atmospheric column reflux tank (39), which is connected with the top of the atmospheric column (3) through an atmospheric column top extraction pipeline (40), and the atmospheric column top extraction pipeline (40) is provided with an atmospheric column condensing device, and the bottom of the atmospheric column reflux tank (39) is connected with an atmospheric column material extraction pipeline (42), and the atmospheric column material extraction pipeline (42) is connected with an atmospheric column reflux pipeline (43), and the atmospheric column reflux pipeline (43) is connected with the upper middle part of the atmospheric column (3).

3. The petroleum atmospheric and vacuum distillation unit according to claim 2, wherein The atmospheric column condensing device adopts an atmospheric column condenser (41), which is connected with the negative pressure column reboiler (17) through a heat supply pipeline (18), and the heat supply pipeline (18) is provided with an atmospheric column heat pump (45).

4. The petroleum atmospheric and vacuum distillation unit according to claim 1, wherein The top of the vacuum column (4) is provided with a vacuum extraction device, and the vacuum extraction device comprises a vacuum column buffer tank (59), the top of the vacuum column buffer tank (59) is connected with the top of the vacuum column (4) through a vacuum column top extraction pipeline (60), the vacuum column top extraction pipeline (60) is provided with a vacuum column condenser (61), and the top and bottom of the vacuum column buffer tank (59) are respectively connected with a vacuum extraction pipeline (63) and a vacuum column buffer tank extraction pipeline (64).

5. The petroleum atmospheric and vacuum distillation unit according to claim 4, wherein The vacuum column condenser (61) is connected with the negative pressure column reboiler (17) through a heat supply pipeline (18), and the heat supply pipeline (18) is provided with a vacuum column heat pump (66).

6. The petroleum atmospheric and vacuum distillation process of any one of claims 1-5, wherein, It comprises sequentially connected primary distillation column (1), negative pressure column (2), atmospheric column (3), vacuum column (4), the heat of the top of atmospheric column (3), vacuum column (4) heats the liquid phase outflow of the hot side outlet of negative pressure column reboiler (17), after being pressurized, provides heat for negative pressure column reboiler (17), after heat exchange through negative pressure column reboiler (17), condenses into liquid water and is introduced into atmospheric column condenser (41), vacuum column condenser (61) respectively for repeated use.

7. The petroleum atmospheric and vacuum distillation process according to claim 6, characterized in that, The steam of primary distillation column (1) top after being pressurized enters heat exchange condenser (27) for heat exchange, condenses into liquid water, is introduced into primary column condenser (22) of primary distillation column (1) top for recycling, and heat exchange condenser (27) provides heat for the middle section reflux of negative pressure column (2).

8. The petroleum atmospheric and vacuum distillation process according to claim 6, characterized in that, The liquid water introduced by the hot side outlet of negative pressure column reboiler (17) is heated in negative pressure column condenser (32) using the heat of the top of negative pressure column (2) and is then recovered.

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