Atmospheric and vacuum five-tower distillation device with energy-saving effect

Abstract

The utility model provides an atmospheric and vacuum five-tower distillation device with an energy-saving effect, which comprises a primary distillation tower, a negative pressure tower, an atmospheric tower and a vacuum tower, the negative pressure tower comprises a first negative pressure tower and a second negative pressure tower, the top of the first negative pressure tower and the top of the second negative pressure tower are respectively connected with a first negative pressure tower reflux device and a second negative pressure tower reflux device; a negative pressure tower reboiler is arranged at the middle lower part of the negative pressure tower I, and the pressure of the negative pressure tower I is higher than that of the negative pressure tower II; the two negative pressure towers are additionally arranged between the primary tower and the atmospheric tower, vaporized gasoline and kerosene components can be separated in time, the irreversible degree of heating and cooling is reduced, and the purpose of saving energy is achieved; due to negative pressure operation of the first negative pressure tower and the second negative pressure tower, the operation temperature in the two negative pressure towers is reduced, utilization of low-grade heat of the system is facilitated, it is guaranteed that all gasoline components and part of kerosene components of crude oil are completely extracted before entering the atmospheric towers, energy consumption is reduced, the heat utilization rate is increased, and the crude oil separation precision is improved.

Description

Technical Field

[0001] The present application relates to the technical field of chemical equipment, and in particular to a five-tower atmospheric and vacuum distillation device with energy-saving effect. Background Art

[0002] The atmospheric and vacuum distillation unit is one of the largest energy-consuming units in the refinery, and the processing energy consumption accounts for 25%-30% of the total energy consumption of the refinery. Therefore, reducing the energy consumption of the atmospheric and vacuum distillation unit is of great significance to the energy conservation and consumption reduction and economic indicators of the refinery.

[0003] The traditional atmospheric and vacuum devices include a primary distillation tower, an atmospheric pressure tower and a vacuum tower. The crude oil after electrical desalting is heated by heat exchange and enters the primary distillation tower. The lightest fraction in the crude oil is distilled in the primary distillation tower. The liquid phase extracted from the bottom of the primary distillation tower is further heated to a specified temperature in a heating furnace through further heat exchange and then enters the atmospheric pressure tower. The atmospheric pressure tower produces gasoline, kerosene and diesel products. The liquid phase extracted from the bottom of the atmospheric pressure tower is heated to a certain temperature through a heat exchange network and a heating furnace, and then enters the vacuum tower to extract heavier products.

[0004] At present, the energy-saving direction of atmospheric and vacuum distillation devices is mainly through the optimization of equipment such as heating furnaces and high-efficiency internals and the optimization of heat exchange networks using "pinch point technology". There is less optimization of the overall process, but there is room for energy-saving optimization in the current atmospheric and vacuum distillation process. Crude oil is preheated in the heat exchange network before entering the primary distillation tower. Some gasoline and kerosene components have been vaporized, but due to the limited separation efficiency of the distillation tower, the gasoline component cannot be completely extracted. This part of the gas is repeatedly cooled and evaporated, resulting in increased energy consumption.

[0005] For example, a petroleum atmospheric and vacuum distillation process with application number 201110102559.1 provides a technical solution, wherein the raw material inlet of the vacuum distillation tower or / and the atmospheric tower is connected to a tube side of a partition wall heat exchanger, the shell side inlet of the partition wall heat exchanger is connected to a molten salt heating furnace, the shell side outlet is connected to a melting tank, and the molten salt heating furnace is connected to the melting tank; mixed inorganic salt powder particles are added to the melting tank, and high-pressure steam or electricity is introduced into the melting tank to melt the mixed inorganic salt powder particles into liquid. When the melting temperature reaches 180°C, the molten salt circulation pump is turned on to force the molten salt to circulate in liquid phase, and the molten salt is transported to the molten salt heating furnace for heating, and the molten salt at the outlet of the molten salt furnace is controlled. The temperature or the inlet temperature of the molten salt flow of the partition heat exchanger is between 350°C and 530°C. The molten salt is transported to the partition heat exchanger to heat the oil flow to 360°C to 440°C, and then returned to the melting tank; the oil flows out of the partition heat exchanger into the atmospheric pressure tower or the vacuum tower; the probability of coking in this method is low, and the heating temperature and the extraction rate of the distillation tower can be increased; in the above scheme, the heating furnace in front of the distillation tower in the prior art is changed to a partition heat exchanger for heat exchange between molten molten salt and oil, and the heating heat of the oil is provided by the partition heat exchanger; as a result, a new partition heat exchanger for heat exchange between molten molten salt and oil needs to be added to the entire system, and the energy saving effect is achieved by optimizing the equipment.

[0006] In the above scheme, the utilization rate of the existing heating furnace is 0, and the gasoline component of the crude oil in the above technical scheme cannot be fully extracted before entering the atmospheric pressure tower.

[0007] The applicant conducted a detailed search of the prior art and found no comparative documents related to "normal and vacuum five-tower distillation".

[0008] In summary, it is necessary to provide a new technical solution to solve the above technical problems. Utility Model Content

[0009] The present application provides a normal-pressure and low-pressure five-tower distillation device with energy-saving effect, comprising a primary distillation tower, a normal-pressure tower and a low-pressure tower, wherein a primary distillation tower reboiler is arranged at the bottom of the primary distillation tower, a primary distillation tower reflux device is connected to the top of the primary distillation tower, a normal-pressure tower reflux device is connected to the top of the normal-pressure tower, a feeding device is arranged at the front of the primary distillation tower, a negative-pressure tower is arranged between the primary distillation tower and the normal-pressure tower, the negative-pressure tower comprises a negative-pressure tower one connected to the primary distillation tower, a negative-pressure tower one reflux device is connected to the top of the negative-pressure tower one, a negative-pressure tower reboiler is arranged at the middle and lower part of the negative-pressure tower one, the negative-pressure tower one is connected to the negative-pressure tower two through a pipeline, a negative-pressure tower one kettle heating system is arranged on the pipeline, a negative-pressure tower two reflux device is connected to the top of the negative-pressure tower two, the pressure of the negative-pressure tower one is higher than the pressure of the negative-pressure tower two, the bottom of the negative-pressure tower two is connected to the middle and lower part of the normal-pressure tower, and a negative-pressure tower two kettle heating system is arranged between the negative-pressure tower two and the normal-pressure tower.

[0010] As a preferred embodiment, at least one of the primary distillation tower reflux device, the negative pressure tower one reflux device, and the negative pressure tower two reflux device is connected to a naphtha separation device; the naphtha separation device comprises a naphtha separation tower feed buffer tank, the naphtha separation tower feed buffer tank is connected to the naphtha separation tower, a naphtha separation tower reflux device is arranged on the top of the naphtha separation tower, the naphtha separation tower reflux device is connected to a light naphtha production pipeline, and a heavy naphtha production pipeline is arranged on the bottom of the naphtha separation tower.

[0011] As a preferred solution, the feeding device includes a crude oil feed pipeline 1, which is connected to a desalting tank, and is provided with a crude oil feed pump 1 and a crude oil heating system; the desalting tank is connected to a flash tank through a crude oil feed pipeline 2, and the flash tank is connected to a primary distillation tower through a crude oil feed pipeline 3.

[0012] As a preferred solution, the crude oil feed pipeline 2 is provided with a crude oil feed pump 2 and a heater 2; and the crude oil feed pipeline 3 is provided with a crude oil feed pump 3.

[0013] As a preferred solution, the top of the flash tank is connected to the secondary flash tank, the bottom of the secondary flash tank is connected to the naphtha separation tower feed buffer tank through the secondary flash tank pipeline, and the top of the secondary flash tank is connected to the non-condensable gas pipeline.

[0014] As a preferred embodiment, the atmospheric pressure tower is connected to the atmospheric pressure stripping tower through an atmospheric pressure tower side line, the atmospheric pressure stripping tower is connected to the atmospheric pressure tower through an atmospheric pressure tower reflux side line, steam is introduced into the atmospheric pressure stripping tower, and one side of the atmospheric pressure stripping tower is connected to an atmospheric pressure stripping tower production pipeline.

[0015] As a preferred solution, the atmospheric tower side line, the atmospheric tower reflux side line, and the atmospheric stripping tower production line each comprise three.

[0016] As a preferred embodiment, the atmospheric pressure stripping tower production pipeline includes atmospheric pressure stripping tower production pipeline 1, atmospheric pressure stripping tower production pipeline 2, and atmospheric pressure stripping tower production pipeline 3.

[0017] As a preferred embodiment, one side of the vacuum stripping tower is connected to the vacuum stripping tower through a vacuum stripping tower side line, the vacuum stripping tower is connected to the vacuum stripping tower through a vacuum stripping tower reflux side line, steam is introduced into the vacuum stripping tower, one side of the vacuum stripping tower is connected to a vacuum stripping side line 2, a vacuum stripping side line 3, a vacuum stripping side line 4, and a vacuum stripping side line 5, the upper part of the vacuum stripping side line 2 is connected to a vacuum stripping side line on the vacuum stripping tower, and the lower part of the vacuum stripping side line 5 is connected to a vacuum stripping side line 6 on the vacuum stripping tower; the bottom of the vacuum stripping tower is connected to a vacuum residue oil production pipeline.

[0018] As a preferred solution, the crude oil heating system is respectively connected to the top of the primary distillation tower, the top of the atmospheric pressure tower, the top of the negative pressure tower one, and the top of the negative pressure tower two, and the gas phase at the top of the primary distillation tower, the gas phase at the top of the atmospheric pressure tower, the gas phase at the top of the negative pressure tower one, and the gas phase at the top of the negative pressure tower two respectively exchange heat with the crude oil in the crude oil heating system to provide heat for the crude oil heating system.

[0019] As a preferred solution, a middle section circulation heat extraction device for the negative pressure tower 2 is arranged in the middle of the negative pressure tower 2.

[0020] As a preferred solution, the circulating heat extraction in the middle section of the second negative pressure tower is used to exchange heat between the liquid phase extracted from the middle section of the second negative pressure tower and the crude oil in the crude oil heating system.

[0021] As a preferred solution, one side of the atmospheric pressure tower is provided with a first-stage circulating heat extraction in the middle section of the atmospheric pressure tower and a second-stage circulating heat extraction in the middle section of the atmospheric pressure tower; one side of the vacuum tower is also provided with a first-stage circulating heat extraction in the middle section of the vacuum tower, a second-stage circulating heat extraction in the middle section of the vacuum tower and a third-stage circulating heat extraction in the middle section of the vacuum tower.

[0022] As a preferred solution, the circulating heat extraction in the middle section of the vacuum tower is used to exchange heat between the liquid phase produced in the middle section of the vacuum tower and the crude oil in the crude oil heating system, thereby providing heat for the crude oil.

[0023] As a preferred solution, a middle section circulating heating device is provided in the middle section of the primary distillation tower.

[0024] As a preferred solution, the atmospheric pressure stripping tower production pipeline 1 is connected to the negative pressure tower kettle heating system and the primary distillation tower middle section circulation heating device in sequence; the atmospheric pressure stripping tower production pipeline 2 is connected to the negative pressure tower kettle heating system and the naphtha fractionation tower raw material heater in sequence; the atmospheric pressure stripping tower production pipeline 3 is connected to the negative pressure tower kettle heating system, the primary distillation tower reboiling device and the primary distillation tower middle section circulation heating device in sequence; the reduction three side line is connected to the negative pressure tower kettle heating system and the primary distillation tower middle section circulation heating device in sequence; the reduction four side line is connected to the negative pressure tower kettle heating system, The reboiling device of the primary distillation tower and the circulating heating device of the middle section of the primary distillation tower are connected in sequence; the side line of reduction five is connected in sequence with the heating system of the second tower kettle of the negative pressure tower, the heating system of the first tower kettle of the negative pressure tower, and the circulating heating device of the middle section of the primary distillation tower; the side line of reduction six is ​​connected in sequence with the heating system of the second tower kettle of the negative pressure tower, the reboiling device of the primary distillation tower, the heating system of the first tower kettle of the negative pressure tower, and the circulating heating device of the middle section of the primary distillation tower; the vacuum residue oil production pipeline is connected in sequence with the heating system of the second tower kettle of the negative pressure tower, the reboiling device of the primary distillation tower, the heating system of the first tower kettle of the negative pressure tower, the circulating heating device of the middle section of the primary distillation tower, and the crude oil heating system.

[0025] As a preferred solution, the first stage circulating heat extraction in the middle section of the atmospheric pressure tower is used to sequentially exchange heat between the liquid phase extracted from the first stage of the middle section of the atmospheric pressure tower and the reboiler of the primary distillation tower, the heating system of the first kettle of the negative pressure tower, and the reboiler of the separation tower; the second stage circulating heat extraction in the middle section of the atmospheric pressure tower is used to sequentially exchange heat between the liquid phase extracted from the second stage of the middle section of the atmospheric pressure tower and the heating system of the second kettle of the negative pressure tower, and the circulating heating device of the middle section of the primary distillation tower; the second stage circulating heat extraction in the middle section of the vacuum tower is used to sequentially exchange heat between the liquid phase extracted from the second stage of the middle section of the vacuum tower and the heating system of the first kettle of the negative pressure tower, the heating system of the second kettle of the negative pressure tower, the reboiler of the primary distillation tower, and the circulating heating device of the middle section of the primary distillation tower; the third stage circulating heat extraction in the middle section of the vacuum tower is used to sequentially exchange heat between the liquid phase extracted from the third stage of the middle section of the vacuum tower and the heating system of the second kettle of the negative pressure tower.

[0026] This application has the following advantages:

[0027] 1. All gasoline components and part of kerosene components of crude oil can be extracted before entering the atmospheric pressure tower, which reduces energy consumption, improves heat utilization rate and improves crude oil separation accuracy.

[0028] 2. Adding two negative pressure towers between the primary distillation tower and the atmospheric pressure tower can separate the vaporized gasoline and kerosene components in time, reduce the irreversibility of heating and cooling, and achieve the purpose of energy saving; and the two negative pressure towers adopt negative pressure operation, which reduces the operating temperature in the negative pressure tower and is conducive to the utilization of low-grade heat in the system;

[0029] 3. Two negative pressure towers extract all gasoline components and part of kerosene components, reducing the amount of materials entering the atmospheric pressure heating furnace, reducing the load of the atmospheric pressure heating furnace, directly reducing the fuel oil consumption of the device, and further achieving the purpose of energy saving;

[0030] 4. Make full use of the heat from the top, middle section and production pipeline of each tower. Only the atmospheric pressure tower and the vacuum tower require external heat sources. The heat sources of the rest of the towers use the heat of the device itself and do not require heat pumps, which improves the utilization rate of heat and further achieves energy-saving effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of this application;

[0032] Figure 2 is a schematic diagram of the heat cycle of the present application;

[0033] 1. Primary distillation tower; 2. Atmospheric pressure tower; 3. Vacuum tower; 4. Circulation heating device for the middle section of primary distillation tower; 5. Reboiling device for primary distillation tower; 6. Reflux tank of primary distillation tower; 8. Condenser at the top of primary distillation tower; 9. Reflux pipeline of primary distillation tower; 10. Production pipeline; 11. Reflux tank of atmospheric pressure tower; 12. Production pipeline at the top of atmospheric pressure tower; 13. Condenser of atmospheric pressure tower; 14. Reflux pipeline of atmospheric pressure tower; 15. Reflux pump of atmospheric pressure tower; 16. Negative pressure tower one; 17. Reflux tank of negative pressure tower one; 19. Condenser of negative pressure tower one; 20. Reflux pipeline of negative pressure tower one; 21. Production pipeline two; 22. Reboiler of negative pressure tower; 23. Pipeline; 24. Negative pressure tower two; 25. Heating system of kettle of negative pressure tower one; 26. Reflux tank of negative pressure tower two; 28. Condenser of negative pressure tower two; 29. Reflux pipeline of negative pressure tower II; 30, production pipeline III; 31, negative pressure tower stripping tower; 32, kerosene production pipeline; 33, kerosene production pump; 34, pipeline of negative pressure tower II kettle; 35, kettle pump of negative pressure tower; 36, atmospheric pressure heating furnace; 37, kettle pipeline of atmospheric pressure tower; 38, reduced pressure heating furnace; 39, feed buffer tank of naphtha separation tower; 40, feed pipeline; 41, naphtha separation tower; 42, feed pump; 43, raw material heater of naphtha fractionation tower; 44, light naphtha production pipeline; 45, heavy naphtha production pipeline; 46, separation tower reflux tank; 47, production pipeline at the top of separation tower; 48, separation tower condenser; 49, separation tower reflux pipeline; 50, crude oil feed pipeline I; 51, separation tower reboiler; 52, desalting tank ; 53, crude oil feed pipeline 2; 54, flash tank; 55, crude oil feed pipeline 3; 56, crude oil feed pump 1; 57, crude oil heating system; 58, crude oil feed pump 2; 59, heater 2; 60, crude oil feed pump 3; 61, secondary flash tank; 62, secondary flash tank pipeline; 64, non-condensable gas pipeline; 65, feed pump 4; 66, atmospheric stripping tower; 67, atmospheric tower side line 1; 68 atmospheric tower side line 2; 69, atmospheric tower side line 3; 70, atmospheric tower reflux side line 1; 71, atmospheric tower reflux side line 2; 72, atmospheric tower reflux side line 3; 73, atmospheric stripping tower production pipeline 1; 74, atmospheric stripping tower production pipeline 2; 75, atmospheric stripping tower production pipeline 3; 76, production pump; 77, atmospheric tower middle section 1 Circulation heat extraction; 78, condensate buffer tank; 79, vacuum tower top pipeline; 80, steam injection device; 81, condenser; 82, condensate production pipeline; 83, vacuum stripping tower; 84, vacuum tower side line; 85, vacuum tower reflux side line; 86, vacuum 2 side line; 87, vacuum 3 side line; 88, vacuum 4 side line; 89, vacuum 5 side line; 90, vacuum 1 side line; 91, vacuum 6 side line; 92, vacuum residue production pipeline; 93, vacuum tower middle section one circulation heat extraction; 94, vacuum tower middle section two circulation heat extraction; 95, vacuum tower second kettle heating system; 96, atmospheric tower middle section two circulation heat extraction; 97, vacuum tower middle section two circulation heat extraction; 98, vacuum tower middle section three circulation heat extraction; 99, crude oil pipeline one; 100, crude oil pipeline two;101, crude oil pipeline three; 102, crude oil pipeline four; 103, crude oil heater one; 104, crude oil heater two; 105, crude oil heater three; 106, crude oil heater four; 107, crude oil heater five; 108, crude oil heater six; 109, crude oil heater seven; 110, crude oil heater eight; 111, crude oil heater nine; 112, crude oil heater ten; 113, crude oil heater eleven; 114, crude oil heater twelve; 115, negative pressure tower one heating pipeline one; 116, negative pressure tower one heating pipeline two; 117, negative pressure tower one heating pipeline three; 118, negative pressure tower one heating pipeline four; 119, negative pressure tower one heater one; 120, negative pressure tower one heater two; 121, negative pressure 122, negative pressure tower one heater four; 123, negative pressure tower one heater five; 124, negative pressure tower one heater six; 125, negative pressure tower one heater seven; 126, negative pressure tower one heater eight; 127, negative pressure tower one heater nine; 128, negative pressure tower one heater ten; 129, negative pressure tower one heater eleven; 130, negative pressure tower one heater twelve; 131, negative pressure tower one heater thirteen; 132, negative pressure tower one heater fourteen; 133, negative pressure tower one heater fifteen; 134, primary distillation tower middle production main pipeline; 135, primary distillation tower middle production branch line one; 136, primary distillation tower middle production branch line two; 137, primary distillation tower middle production branch line three; 138, primary distillation tower middle production branch line Pipeline 4; 139, primary distillation tower middle extraction branch line 5; 140, primary distillation tower middle extraction branch line 6; 141, primary distillation tower middle extraction branch line 7; 142, primary distillation tower middle extraction branch line 8; 143, primary distillation tower middle extraction branch line 9; 144, primary distillation tower middle reflux main pipeline; 145, primary distillation tower middle heater 1; 146, primary distillation tower middle heater 2; 147, primary distillation tower middle heater 3; 148, primary distillation tower middle heater 4; 149, primary distillation tower middle heater 5; 150, primary distillation tower middle heater 6; 151, primary distillation tower middle heater 7; 152, primary distillation tower middle heater 8; 153, primary distillation tower middle heater 9; 154, primary distillation tower reboiler feed main pipeline; 1 55. Primary distillation tower reboiler feed branch pipeline one; 156. Primary distillation tower reboiler feed branch pipeline two; 157. Primary distillation tower reboiler feed branch pipeline three; 158. Primary distillation tower reboiler feed branch pipeline four; 159. Primary distillation tower reboiler feed branch pipeline five; 160. Primary distillation tower reboiler feed branch pipeline six; 161. Primary distillation tower reboiler discharge main pipeline; 162. Primary distillation tower reboiler one; 163. Primary distillation tower reboiler two; 164. Primary distillation tower reboiler three; 165. Primary distillation tower reboiler four; 166. Primary distillation tower reboiler five; 167. Primary distillation tower reboiler six; 168. Negative pressure tower two heating pipeline one; 169. Negative pressure tower two heating pipeline two; 170. Negative pressure tower two heater one; 171. Negative pressure tower two heater two; 172. Heater 3 of negative pressure tower 2; 173. Heater 4 of negative pressure tower 2;174, negative pressure tower 2 heater 5; 175, negative pressure tower 2 heater 6; 176, negative pressure tower 2 heater 7; 177, negative pressure tower 2 heater 8; 178, negative pressure tower 2 heater 9; 179, negative pressure tower 2 heater 10. ; DETAILED DESCRIPTION

[0034] The following is combined with Figure 1 , Attachment Figure 2 The specific implementation of the utility model is described in detail. It should be noted that the specific implementation described here is only used to illustrate and explain the utility model, and is not used to limit the utility model.

[0035] Embodiment 1:

[0036] The present embodiment provides a five-tower atmospheric and vacuum distillation device with energy-saving effect, comprising a primary distillation tower 1, an atmospheric pressure tower 2, and a vacuum tower 3. Preferably, the operating pressure of the primary distillation tower 1 is reduced to between slightly positive pressure and slightly negative pressure, and a primary distillation tower middle section circulation heating device 4 is arranged in the middle section of the primary distillation tower 1 to circulate and heat the materials in the middle section of the primary distillation tower 1. By reducing the operating pressure of the primary distillation tower 1 and increasing the circulation heating in the middle section of the primary distillation tower 1, the heat grade required for the primary distillation tower 1 is reduced and the energy utilization efficiency is increased. A primary distillation tower reboiler 5 is arranged at the bottom of the primary distillation tower 1, and the primary distillation tower reboiler 5 is heated by a heat exchange network. A primary distillation tower reflux device is connected to the top of the primary distillation tower 1. Specifically, the primary distillation tower reflux device comprises a primary distillation tower reflux tank 6. The primary distillation tower reflux tank 6 The top of the primary distillation tower 1 is connected through the primary distillation tower top extraction pipeline, the primary distillation tower top extraction pipeline is provided with a primary distillation tower top condenser 8, the bottom of the primary distillation tower reflux tank 6 is connected with the primary distillation tower reflux tank extraction pipeline, the primary distillation tower reflux tank extraction pipeline is provided with an extraction pump, the primary distillation tower reflux tank extraction pipeline is respectively connected with the primary distillation tower reflux pipeline 9 and the extraction pipeline 10, the primary distillation tower reflux pipeline 9 is connected with the middle and upper part of the primary distillation tower 1; the gas phase at the top of the primary distillation tower 1 enters the primary tower reflux tank 6 after condensation by the primary distillation tower top condenser 8, the gas phase in the primary tower reflux tank 6 is extracted through the non-condensable gas pipeline, a part of the liquid phase in the primary tower reflux tank 6 is refluxed to the primary distillation tower 1 through the primary tower reflux pipeline 9, and a part of it is extracted as light gasoline through the extraction pipeline 10; atmospheric pressure tower The top of the atmospheric tower 2 is connected with an atmospheric tower reflux device, and the atmospheric tower reflux device includes an atmospheric tower reflux tank 11, which is connected to the top of the atmospheric tower 2 through an atmospheric tower top extraction pipeline 12, and the atmospheric tower top extraction pipeline 12 is connected with an atmospheric tower condenser 13, and the bottom of the atmospheric tower reflux tank 11 is connected with an atmospheric tower reflux pipeline 14, and the atmospheric tower reflux pipeline 14 is provided with an atmospheric tower reflux pump 15, and the atmospheric tower reflux pipeline 14 is connected to the upper part of the atmospheric tower 2; the gas phase at the top of the atmospheric tower 2 is condensed by the atmospheric tower condenser 13 and enters the atmospheric tower reflux tank 11, and the liquid phase in the atmospheric tower reflux tank 11 is refluxed to the atmospheric tower 2 through the atmospheric tower reflux pipeline 14; the front part of the primary distillation tower 1 is provided with a feeding device, and the crude oil passes through The feeding device enters the primary distillation tower 1 for processing. A negative pressure tower is arranged between the primary distillation tower 1 and the atmospheric pressure tower 2. The negative pressure tower includes a negative pressure tower 16 connected to the primary distillation tower 1. The top of the negative pressure tower 16 is connected to a negative pressure tower reflux device. The negative pressure tower reflux device includes a negative pressure tower reflux tank 17. The negative pressure tower reflux tank 17 is connected to the top of the negative pressure tower 16 through a negative pressure tower top extraction pipeline. A negative pressure tower condenser 19 is arranged on the negative pressure tower top extraction pipeline. The bottom of the negative pressure tower reflux tank 17 is connected to a negative pressure tower reflux tank extraction pipeline. The negative pressure tower reflux tank extraction pipeline is respectively connected to a negative pressure tower reflux pipeline 20 and an extraction pipeline 21. The negative pressure tower reflux pipeline 20 is connected to the middle and upper part of the negative pressure tower 16.The gas phase at the top of the negative pressure tower 16 is condensed by the negative pressure tower 1 condenser 19 and enters the negative pressure tower 1 reflux tank 17. A part of it is refluxed to the negative pressure tower 16 through the negative pressure tower 1 reflux pipeline 20, and a part of it is produced through the production pipeline 21. A negative pressure tower reboiler 22 is arranged in the middle and lower part of the negative pressure tower 16. The negative pressure tower reboiler 22 provides heat for crude oil fractionation. The negative pressure tower 16 is connected to the negative pressure tower 24 through the pipeline 23. The pipeline 23 is provided with a negative pressure tower. The first tower kettle heating system 25, the negative pressure tower first tower kettle heating system 25 is set to obtain the heat required for evaporation in the form of high-temperature feed, the top of the negative pressure tower 24 is connected to the negative pressure tower 2 reflux device, the negative pressure tower 2 reflux device includes a negative pressure tower 2 reflux pipeline 29 connected to the upper part of the negative pressure tower 24, and the negative pressure tower 2 reflux pipeline 29 is sequentially provided with a negative pressure tower 2 condenser 28, a negative pressure tower 2 reflux tank 26, and a negative pressure tower 2 reflux tank 26 at the bottom of the negative pressure tower 2 reflux tank 26. The flow pipeline 29 is connected to the production pipeline three 30; preferably, in order to improve the fractionation accuracy, the middle and lower part of the negative pressure tower two 24 is connected to the negative pressure tower stripping tower 31, and the bottom of the negative pressure tower stripping tower 31 is connected to the kerosene production pipeline 32, and the kerosene production pipeline 32 is provided with a kerosene production pump 33; the pressure of the negative pressure tower one 16 is higher than the pressure of the negative pressure tower two 24, and the bottom of the negative pressure tower two 24 is connected to the middle and lower part of the atmospheric pressure tower 2 through the negative pressure tower two kettle pipeline 34. The vacuum tower 2 kettle pipeline 34 is provided with a vacuum tower kettle pump 35, a vacuum tower 2 kettle heating system 95, and a normal pressure heating furnace 36. The normal pressure heating furnace 36 is used to heat the materials in the vacuum tower 2 kettle. The kettle of the atmospheric tower 2 is connected to the middle and upper part of the vacuum tower 3 through the atmospheric tower kettle pipeline 37. The atmospheric tower kettle pipeline 37 is provided with a vacuum heating furnace 38. The vacuum heating furnace 38 is used to heat the materials in the atmospheric tower 2 kettle. ;

[0037] In this embodiment, two negative pressure towers are added between the primary distillation tower 1 and the atmospheric pressure tower 2. The negative pressure tower reboiler 22 arranged in the lower part of the negative pressure tower 16 provides heat for crude oil fractionation. The setting of the negative pressure tower kettle heating system 25 obtains the heat required for evaporation in the form of high-temperature feed, and can separate the vaporized gasoline and kerosene components in time, reducing the irreversibility of heating and cooling, and achieving the purpose of energy saving. The negative pressure tower 16 and the negative pressure tower 24 extract all gasoline components and part of the kerosene components, reducing the amount of material entering the atmospheric pressure heating furnace 36, reducing the load of the atmospheric pressure heating furnace 36, directly reducing the fuel oil consumption of the device, and further achieving the purpose of energy saving. In addition, the negative pressure tower 16 and the negative pressure tower 24 adopt negative pressure operation, which reduces the operating temperature in the tower and is beneficial to the utilization of low-grade heat in the system.

[0038] Embodiment 2:

[0039] This embodiment can further process the materials extracted from the top of the primary distillation tower 1, the negative pressure tower 16, and the negative pressure tower 24 to produce naphtha, specifically:

[0040] At least one of the primary distillation tower reflux device, the negative pressure tower 1 reflux device, and the negative pressure tower 2 reflux device is connected to the naphtha separation device. In this embodiment, the primary distillation tower reflux device, the negative pressure tower 1 reflux device, and the negative pressure tower 2 reflux device are respectively connected to the naphtha separation device as an example. The naphtha separation device includes a naphtha separation tower feed buffer tank 39, a production pipeline 10, a production pipeline 21, and a production pipeline 30 are respectively connected to the naphtha separation tower feed buffer tank 39, and the naphtha separation tower The feed buffer tank 39 is connected to the naphtha separation tower 41 through a feed pipeline 40. A feed pump 42 and a naphtha fractionation tower raw material heater 43 are provided on the feed pipeline 40. A separation tower reboiler 51 is provided at the lower part of the naphtha separation tower 41. A naphtha separation tower reflux device is provided at the top of the naphtha separation tower 41. The naphtha separation tower reflux device is connected to a light naphtha production line 44. A heavy naphtha production line 45 is provided at the bottom of the naphtha separation tower 41.

[0041] The naphtha separation tower reflux device includes a separation tower reflux tank 46, which is connected to the top of the naphtha separation tower 41 through a separation tower top production pipeline 47, a separation tower condenser 48 is provided on the separation tower top production pipeline 47, a separation tower reflux pipeline 49 is provided at the bottom of the separation tower reflux tank 46, and the separation tower reflux pipeline 49 is connected to the middle and upper part of the naphtha separation tower 41.

[0042] The materials extracted from the tops of the primary distillation tower 1, the negative pressure tower 16, and the negative pressure tower 2 24 can be further separated by the naphtha separation device to produce light naphtha and heavy naphtha.

[0043] Embodiment three:

[0044] This embodiment can further reduce the gas loss in the primary distillation tower 1, specifically:

[0045] The feeding device includes a crude oil feed pipeline 50, which is connected to a desalter 52, which is connected to a flash tank 54 via a crude oil feed pipeline 53, which is connected to a primary distillation tower 1 via a crude oil feed pipeline 55; a crude oil feed pump 56 and a crude oil heating system 57 are provided on the crude oil feed pipeline 50; a crude oil feed pump 58 and a heater 59 are provided on the crude oil feed pipeline 53; a crude oil feed pump 60 is provided on the crude oil feed pipeline 55; the crude oil enters the electric desalter 52 for desalting and dehydration, and the desalted and dehydrated oil enters the primary distillation tower 1 after flash evaporation.

[0046] Furthermore, the top of the flash tank 54 is connected to the secondary flash tank 61, the bottom of the secondary flash tank 61 is connected to the naphtha separation tower feed buffer tank 39 through the secondary flash tank pipeline 62, and the top of the secondary flash tank 61 is connected to the non-condensable gas pipeline 64; the secondary flash tank pipeline 62 is provided with a feed pump 4 65.

[0047] In order to reduce the gas loss in the primary distillation tower 1, a flash tank is added before the crude oil is heated by the heat exchange network and enters the primary distillation tower 1. The flash tank can be divided into two or more stages. The operating pressure of the flash tank is higher than that of the primary distillation tower 1, which can reduce the amount of non-condensable gas.

[0048] Embodiment 4:

[0049] In this embodiment, the product quality and fractionation accuracy of atmospheric tower 2 can be guaranteed, the product quality and flash point can be guaranteed, the partial pressure of light components can be reduced, and the extraction rate of crude oil can be improved;

[0050] Specifically, the atmospheric pressure tower 2 is connected to the atmospheric pressure stripping tower 66 through the atmospheric pressure tower side line, and the atmospheric pressure stripping tower 66 is connected to the atmospheric pressure tower 2 through the atmospheric pressure tower reflux side line. Steam is introduced into the atmospheric pressure stripping tower 66, and the steam provides power for the atmospheric pressure stripping tower 66. One side of the atmospheric pressure stripping tower 66 is connected to the atmospheric pressure stripping tower production pipeline, and the atmospheric pressure stripping tower production pipeline produces the corresponding product. In this embodiment, the atmospheric pressure tower is connected to the atmospheric pressure stripping tower 66 through the atmospheric pressure tower side line 1 67, the atmospheric pressure tower side line 2 68, and the atmospheric pressure stripping tower side line 3 69. The atmospheric pressure stripping tower 66 is connected to the atmospheric pressure tower 2 through the atmospheric pressure tower reflux side line 1 70, the atmospheric pressure tower reflux side line 2 71, and the atmospheric pressure tower reflux side line 3 72, respectively. One side of the atmospheric pressure stripping tower 66 is connected to the atmospheric pressure stripping tower production pipeline 1 73 and the atmospheric pressure stripping tower production pipeline 2 74. , atmospheric stripping tower production pipeline three 75, the atmospheric stripping tower production pipeline one 73, the atmospheric stripping tower production pipeline two 74, and the atmospheric stripping tower production pipeline three 75 are all provided with production pumps 76, the atmospheric stripping tower production pipeline one 73 is connected to the kerosene production pipeline 32 for producing kerosene, the atmospheric stripping tower production pipeline two 74 produces light diesel oil, and the atmospheric stripping tower production pipeline three 75 is used to produce heavy diesel oil; the atmospheric pressure tower middle section one stage circulation heat extraction 77 and the atmospheric pressure tower middle section two stage circulation heat extraction 96 are provided in the middle part of one side of the atmospheric pressure tower 2, so as to make full use of the heat of the liquid phase in the middle section of the atmospheric pressure tower 2; the atmospheric pressure tower 2 in this embodiment is provided with three side line products and two middle section refluxes to evenly distribute the gas-liquid load of the whole tower and to optimize the heat exchange network of the whole device, so as to recover the excess heat of the whole tower and use it to heat the crude oil and generate steam.

[0051] Embodiment five:

[0052] This embodiment describes the vacuum tower 3, specifically:

[0053] A condensed oil production device is provided at the top of the vacuum tower 3, and the condensed oil production device includes a condensed oil buffer tank 78. The condensed oil buffer tank 78 is connected to the top of the vacuum tower 3 through a vacuum tower top pipeline 79. The vacuum tower top pipeline 79 is provided with a steam injection device 80 and a condenser 81. The steam injection device 80 is used for vacuuming, extracting the top gas of the vacuum tower 3 and ensuring the vacuum degree of the top; the bottom of the condensed oil buffer tank 78 is connected to a condensed oil production pipeline 82; the top gas phase of the vacuum tower 4 enters the condensed oil buffer tank 78 after being cooled by the condenser 81, and the condensed oil and water are produced from the bottom of the condensed oil buffer tank 78 through the condensed oil production pipeline 82.

[0054] One side of the vacuum stripping tower 3 is connected to the vacuum stripping tower 83 via a vacuum stripping tower side line 84, and the vacuum stripping tower 83 is connected to the vacuum stripping tower 3 via a vacuum stripping tower reflux side line 85. Steam is introduced into the vacuum stripping tower 83, and one side of the vacuum stripping tower 83 is connected to a vacuum stripping side line 86, a vacuum stripping side line 87, a vacuum stripping side line 88, and a vacuum stripping side line 89. The upper part of the vacuum stripping side line 86 is connected to a vacuum stripping side line 90 on the vacuum stripping tower 3, and the lower part of the vacuum stripping side line 89 is connected to a vacuum stripping side line 91 on the vacuum stripping tower 3; the bottom of the vacuum stripping tower 3 is connected to a vacuum residue oil. Production pipeline 92; one side line 90, two side line 86, three side line 87, four side line 88, five side line 89, six side line 91 are used to produce different substances according to different crude oils, such as lubricating oil type, different grades of lubricating mixed oil are produced, and fuel type uses different grades of wax oil, etc.; one side of the vacuum tower 3 is provided with a vacuum tower middle section first stage circulation heat extraction 93, a vacuum tower middle section second stage circulation heat extraction 97, and a vacuum tower middle section third stage circulation heat extraction 98. The above-mentioned circulation heat extraction is used to utilize the heat of the middle section liquid phase of the vacuum tower to reduce the condensation amount at the top of the vacuum tower.

[0055] Embodiment six:

[0056] This embodiment describes the primary distillation tower middle section circulation heating device 4, the primary distillation tower reboiling device 5, the negative pressure tower first kettle heating system 25, the crude oil heating system 57, and the negative pressure tower second kettle heating system 95, specifically:

[0057] The primary distillation tower middle section circulation heating device 4 comprises a primary distillation tower middle section extraction main pipeline 134, which is respectively connected to the primary distillation tower middle section extraction branch line 1 135, the primary distillation tower middle section extraction branch line 2 136, the primary distillation tower middle section extraction branch line 3 137, the primary distillation tower middle section extraction branch line 4 138, the primary distillation tower middle section extraction branch line 5 139, the primary distillation tower middle section extraction branch line 6 140, the primary distillation tower middle section extraction branch line 7 141, and the primary distillation tower middle section extraction branch line 8 142. 41, the middle extraction branch line eight of the primary distillation tower 142, the middle extraction branch line nine of the primary distillation tower 143 are connected, the middle extraction branch line one of the primary distillation tower 135, the middle extraction branch line two of the primary distillation tower 136, the middle extraction branch line three of the primary distillation tower 137, the middle extraction branch line four of the primary distillation tower 138, the middle extraction branch line five of the primary distillation tower 139, the middle extraction branch line six of the primary distillation tower 140, the middle extraction branch line seven of the primary distillation tower 141, the middle extraction branch line The extraction branch line eight 142 and the primary distillation tower middle extraction branch line nine 143 are respectively connected to the primary distillation tower middle reflux main pipeline 144, and the primary distillation tower middle extraction branch line one 135, the primary distillation tower middle extraction branch line two 136, the primary distillation tower middle extraction branch line three 137, the primary distillation tower middle extraction branch line four 138, the primary distillation tower middle extraction branch line five 139, the primary distillation tower middle extraction branch line six 140, the primary distillation tower middle extraction branch line seven 141, the primary distillation tower The middle production branch line eight 142 and the middle production branch line nine 143 of the primary distillation tower are respectively provided with a middle heater one 145 of the primary distillation tower, a middle heater two 146 of the primary distillation tower, a middle heater three 147 of the primary distillation tower, a middle heater four 148 of the primary distillation tower, a middle heater five 149 of the primary distillation tower, a middle heater six 150 of the primary distillation tower, a middle heater seven 151 of the primary distillation tower, a middle heater eight 152 of the primary distillation tower, and a middle heater nine 153 of the primary distillation tower.

[0058] The primary distillation tower reboiler device 5 comprises a primary distillation tower reboiler feed main pipeline 154, which is respectively connected to a primary distillation tower reboiler feed branch pipeline 1 155, a primary distillation tower reboiler feed branch pipeline 2 156, a primary distillation tower reboiler feed branch pipeline 3 157, a primary distillation tower reboiler feed branch pipeline 4 158, a primary distillation tower reboiler feed branch pipeline 5 159, and a primary distillation tower reboiler feed branch pipeline 6 160, and the primary distillation tower reboiler feed branch pipeline 1 155, a primary distillation tower reboiler feed branch pipeline 2 156, a primary distillation tower reboiler feed branch pipeline 3 157, a primary distillation tower reboiler feed branch pipeline 4 158, a primary distillation tower reboiler feed branch pipeline 5 159, and a primary distillation tower reboiler feed branch pipeline 6 The tower reboiler feed branch pipe six 160 is respectively connected to the primary distillation tower reboiler discharge main pipe 161, and the primary distillation tower reboiler discharge main pipe 161 is connected to the primary distillation tower 1, and the primary distillation tower reboiler feed branch pipe one 155, the primary distillation tower reboiler feed branch pipe two 156, the primary distillation tower reboiler feed branch pipe three 157, the primary distillation tower reboiler feed branch pipe four 158, the primary distillation tower reboiler feed branch pipe five 159, and the primary distillation tower reboiler feed branch pipe six 160 are respectively provided with a primary distillation tower reboiler one 162, a primary distillation tower reboiler two 163, a primary distillation tower reboiler three 164, a primary distillation tower reboiler four 165, a primary distillation tower reboiler five 166, and a primary distillation tower reboiler six 167.

[0059] The negative pressure tower kettle heating system 25 includes a negative pressure tower heating pipeline 1 115, a negative pressure tower heating pipeline 2 116, a negative pressure tower heating pipeline 3 117, and a negative pressure tower heating pipeline 4 118. The negative pressure tower heating pipeline 1 115, the negative pressure tower heating pipeline 2 116, the negative pressure tower heating pipeline 3 117, and the negative pressure tower heating pipeline 4 118 are respectively connected to the negative pressure tower 2 24; the negative pressure tower heating pipeline 1 115 is provided with a negative pressure tower heater 1 119, a negative pressure tower heater 2 120, and a negative pressure tower heater 3 121; the negative pressure tower heating pipeline 1 The negative pressure tower one heater four 122, the negative pressure tower one heater five 123, the negative pressure tower one heater six 124, and the negative pressure tower one heater seven 125 are arranged on the negative pressure tower one heating pipeline three 117; the negative pressure tower one heater eight 126, the negative pressure tower one heater nine 127, the negative pressure tower one heater ten 128, and the negative pressure tower one heater eleven 129 are arranged on the negative pressure tower one heating pipeline four 118; the negative pressure tower one heater twelve 130, the negative pressure tower one heater thirteen 131, the negative pressure tower one heater fourteen 132, and the negative pressure tower one heater fifteen 133 are arranged on the negative pressure tower one heating pipeline four 118.

[0060] The crude oil heating system 57 includes a crude oil pipeline 1 99, a crude oil pipeline 2 100, a crude oil pipeline 3 101, and a crude oil pipeline 4 102. The crude oil pipeline 1 99, the crude oil pipeline 2 100, the crude oil pipeline 3 101, and the crude oil pipeline 4 102 are respectively connected to the desalting tank 52. The crude oil pipeline 1 99 is provided with a crude oil heater 1 103 and a crude oil heater 2 104; the crude oil pipeline 2 100 is provided with a crude oil heater 3 105, a crude oil heater 4 106, a crude oil heater 5 107, and a crude oil heater 6 108; the crude oil pipeline 3 101 is provided with a crude oil heater 7 109, a crude oil heater 8 110, and a crude oil heater 9 111; the crude oil pipeline 4 102 is provided with a crude oil heater 10 112, a crude oil heater 113, and a crude oil heater 12 114.

[0061] The negative pressure tower 2 kettle heating system 95 includes a negative pressure tower 2 heating pipeline 168 and a negative pressure tower 2 heating pipeline 169, which are respectively connected to the normal pressure heating furnace 36, and the negative pressure tower 2 heating pipeline 168 is provided with a negative pressure tower 2 heater 170, a negative pressure tower 2 heater 171, a negative pressure tower 2 heater 3 172, a negative pressure tower 2 heater 4 173, and a negative pressure tower 2 heater 5 174, and the negative pressure tower 2 heating pipeline 2 169 is provided with a negative pressure tower 2 heater 6 175, a negative pressure tower 2 heater 7 176, a negative pressure tower 2 heater 8 177, a negative pressure tower 2 heater 9 178, and a negative pressure tower 2 heater 179.

[0062] Embodiment seven:

[0063] In order to further achieve the effect of energy saving, this embodiment describes the use of heat at the top of the primary distillation tower 1, the top of the atmospheric tower 2, the top of the negative pressure tower 16, the top of the negative pressure tower 24, the middle section of the negative pressure tower 24, and the middle section of the vacuum tower. The heat utilization of this embodiment does not require the use of a heat pump, which further achieves the effect of energy saving. Specifically:

[0064] The crude oil heating system 57 is connected to the top of the primary distillation tower 1, the top of the atmospheric tower 2, the top of the negative pressure tower 16, and the top of the negative pressure tower 24 respectively. The liquid phase of the middle section of the negative pressure tower 2 produced by the negative pressure tower middle section circulation heat extraction 94 and the liquid phase of the middle section of the vacuum tower produced by the middle section of the vacuum tower first section circulation heat extraction 93 are respectively exchanged with the crude oil in the crude oil heating system 57;

[0065] The gas phase at the top of the primary distillation tower 1, the gas phase at the top of the atmospheric pressure tower 2, the gas phase at the top of the negative pressure tower 16, and the gas phase at the top of the negative pressure tower 24 are respectively heat-exchanged with the crude oil in the crude oil heating system 57 to provide heat for the crude oil heating system 57; the top of the primary distillation tower 1 is connected to the crude oil heating system 57, the crude oil heating system 57 is connected to the primary distillation tower top condenser 8, the gas phase at the top of the primary distillation tower 1 is heat-exchanged with the crude oil in the crude oil heating system 57, and after the heat exchange, it enters the primary distillation tower top condenser 8 for further condensation; more specifically, the top of the primary distillation tower 1 is connected to the crude oil heater 103, the gas phase at the top of the primary distillation tower 1 is heat-exchanged with the crude oil in the crude oil heater 103 to provide heat for the crude oil heater 103, and after the heat exchange, it enters the primary distillation tower top condenser 8 for further condensation.

[0066] The top of the atmospheric tower 2 is connected to the crude oil heating system 57, the crude oil heating system 57 is connected to the atmospheric tower condenser 13, the gas phase at the top of the atmospheric tower 2 exchanges heat with the crude oil in the crude oil heating system 57, and after the heat exchange, enters the atmospheric tower condenser 13 for further condensation; specifically, the top of the atmospheric tower 2 is connected to the crude oil heater + 112, the gas phase at the top of the atmospheric tower 2 exchanges heat with the crude oil in the crude oil heater + 112, and heats the crude oil heater + 112; after the heat exchange, it enters the atmospheric tower condenser 13 for further condensation.

[0067] The top of the negative pressure tower 16 is connected to the crude oil heating system 57, and the crude oil heating system 57 is connected to the negative pressure tower condenser 19. The gas phase at the top of the negative pressure tower 16 exchanges heat with the crude oil in the crude oil heating system 57, and after the heat exchange, it enters the negative pressure tower condenser 19 for further condensation; the top of the negative pressure tower 16 is connected to the crude oil heater five 107, and the gas phase of the negative pressure tower 16 exchanges heat with the crude oil in the crude oil heater five 107 to provide heat for the crude oil heater five 107, and after the heat exchange, it enters the negative pressure tower condenser 19 for further condensation.

[0068] The top of the negative pressure tower 24 is connected to the crude oil heating system 57, and the crude oil heating system 57 is connected to the negative pressure tower 2 condenser 28. The gas phase at the top of the negative pressure tower 24 exchanges heat with the crude oil in the crude oil heating system 57, and enters the negative pressure tower 2 condenser 28 for further condensation after heat exchange; the top of the negative pressure tower 24 is connected to the crude oil heater 3 105 and the crude oil heater 7 109 respectively, and the gas phase at the top of the negative pressure tower 24 exchanges heat with the crude oil in the crude oil heater 3 105 and the crude oil in the crude oil heater 7 109, heats the crude oil heater 3 105 and the crude oil heater 7 109, and enters the negative pressure tower 2 condenser 28 for further condensation after heat exchange.

[0069] The circulating heat extraction 94 in the middle section of the negative pressure tower two is used to exchange heat between the liquid phase extracted from the middle section of the negative pressure tower two and the crude oil in the crude oil heating system 57, and the liquid phase after heat exchange cooling returns to the negative pressure tower two 24; specifically: the circulating heat extraction 94 in the middle section of the negative pressure tower two is used to exchange heat between the liquid phase extracted from the middle section of the negative pressure tower two and the crude oil heater nine 111 and the crude oil heater six 108 in sequence, the liquid phase extracted from the middle section of the negative pressure tower two is subjected to a primary heat exchange with the crude oil in the crude oil heater nine 111 and a secondary heat exchange with the crude oil in the crude oil heater six 108, so as to provide heat for the crude oil and make full use of the heat of the liquid phase in the middle section of the negative pressure tower two, and the liquid phase after secondary heat exchange cooling returns to the negative pressure tower two 24.

[0070] The circulating heat extraction 93 of the first section of the middle section of the vacuum tower is used to exchange heat between the liquid phase produced from the first section of the middle section of the vacuum tower and the crude oil in the crude oil heating system 57, so as to provide heat for the crude oil, and the liquid phase after heat exchange cooling is returned to the vacuum tower 3; specifically, the circulating heat extraction 93 of the first section of the vacuum tower is used to exchange heat between the liquid phase produced from the first section of the middle section of the vacuum tower and the crude oil heater 2 104, the crude oil heater 11 113, the crude oil heater 8 110, and the crude oil heater 4 106 in sequence, the liquid phase produced from the first section of the vacuum tower is subjected to a first-stage heat exchange with the crude oil in the crude oil heater 2 104, a second-stage heat exchange with the crude oil in the crude oil heater 113, a third-stage heat exchange with the crude oil in the crude oil heater 8 110, and a fourth-stage heat exchange with the crude oil in the crude oil heater 4 106, so as to provide heat for the crude oil, and the liquid phase after the fourth-stage heat exchange cooling is returned to the vacuum tower 3.

[0071] This embodiment makes full use of the gas phase at the top of the primary distillation tower 1, the gas phase at the top of the atmospheric pressure tower 2, the gas phase at the top of the negative pressure tower 16, and the gas phase at the top of the negative pressure tower 24; utilizes the heat of the liquid phase extracted by the circulating heat extraction 94 in the middle section of the negative pressure tower 2 and the liquid phase extracted by the circulating heat extraction 93 in the middle section of the vacuum tower, thereby saving energy and further achieving the effect of energy saving.

[0072] Embodiment eight:

[0073] This embodiment describes the heat utilization of atmospheric pressure stripping tower production pipeline 1 73, atmospheric pressure stripping tower production pipeline 2 74, atmospheric pressure stripping tower production pipeline 3 75, atmospheric pressure tower middle section one stage circulation heat extraction 77, atmospheric pressure tower middle section two stage circulation heat extraction 96. The heat utilization of this embodiment does not require the use of a heat pump, which further achieves the effect of energy saving. Specifically:

[0074] The atmospheric stripping tower production pipeline 73 is connected to the negative pressure tower kettle heating system 25 and the primary distillation tower middle section circulating heating device 4 in sequence. The material produced by the atmospheric stripping tower production pipeline 73 enters the negative pressure tower kettle heating system 25, and is used as a heat source to perform a primary heat exchange with the negative pressure tower kettle material; after the primary heat exchange, it enters the primary distillation tower middle section circulating heating device 4, and is used as a heat source to perform a secondary heat exchange with the primary distillation tower middle section circulating material. After the secondary heat exchange, kerosene is produced through the atmospheric stripping tower production pipeline 73, which fully utilizes the atmospheric stripping tower production pipeline 73. The heat of the produced material; more specifically, the atmospheric pressure stripping tower production pipeline 73 is connected in sequence with the negative pressure tower heater 12 130 and the primary distillation tower middle heater 145, the material produced by the atmospheric pressure stripping tower production pipeline 73 undergoes a primary heat exchange with the negative pressure tower heater 12 130 to provide heat for the negative pressure tower heater 12 130, after the primary heat exchange, it undergoes a secondary heat exchange with the primary distillation tower middle heater 145 to provide heat for the primary distillation tower middle heater 145, after the secondary heat exchange, kerosene is produced through the atmospheric pressure stripping tower production pipeline 73.

[0075] The atmospheric stripping tower production line 274 is connected to the negative pressure tower kettle heating system 25 and the naphtha fractionation tower raw material heater 43 in sequence. The material produced by the atmospheric stripping tower production line 274 enters the negative pressure tower kettle heating system 25 and is used as a heat source to perform a primary heat exchange with the negative pressure tower kettle material. After the primary heat exchange, the material enters the naphtha fractionation tower raw material heater 43 and is used as a heat source to perform a secondary heat exchange with naphtha. After the secondary heat exchange, light diesel oil is produced through the atmospheric stripping tower production line 274, which fully utilizes the atmospheric stripping tower production line 274. heat of the material; specifically, the atmospheric pressure stripping tower production pipeline 2 74 is connected with the negative pressure tower heater 14 132 and the naphtha fractionation tower raw material heater 43 in sequence, the material produced by the atmospheric pressure stripping tower production pipeline 2 74 undergoes a primary heat exchange with the negative pressure tower heater 14 132 to provide heat for the negative pressure tower heater 14 132, and after the primary heat exchange, it undergoes a secondary heat exchange with the naphtha fractionation tower raw material heater 43 to provide heat for the naphtha fractionation tower raw material heater 43, and after the secondary heat exchange, light diesel is produced through the atmospheric pressure stripping tower production pipeline 2 74.

[0076] The atmospheric stripping tower extraction pipeline 375 is connected to the negative pressure tower kettle heating system 25, the primary distillation tower reboiling device 5, and the primary distillation tower middle section circulating heating device 4 in sequence; the material extracted from the atmospheric stripping tower extraction pipeline 375 enters the negative pressure tower kettle heating system 25, and is used as a heat source to perform a primary heat exchange with the negative pressure tower kettle material; after the primary heat exchange, it enters the primary distillation tower reboiling device 5, and is used as a heat source to perform a secondary heat exchange with the primary distillation tower kettle material, and after the secondary heat exchange, it enters the primary distillation tower middle section circulating heating device 4, and is used as a heat source to perform a tertiary heat exchange with the primary distillation tower middle section circulating material. After the tertiary heat exchange, heavy diesel is extracted through the atmospheric stripping tower extraction pipeline 375, which makes full use of the atmospheric stripping tower extraction pipeline 375. 5. The heat of the produced material; specifically, the atmospheric pressure stripping tower production line 375 is connected with the negative pressure tower one heater 7125, the primary distillation tower reboiler 3164, and the primary distillation tower middle heater 8152 in sequence, the material produced by the atmospheric pressure stripping tower production line 375 performs a primary heat exchange with the negative pressure tower one heater 7125 to provide heat for the negative pressure tower one heater 7125, after the primary heat exchange, performs a secondary heat exchange with the primary distillation tower reboiler 3164 to provide heat for the primary distillation tower reboiler 3164, after the secondary heat exchange, performs a tertiary heat exchange with the primary distillation tower middle heater 8152 to provide heat for the primary distillation tower middle heater 8152, after the tertiary heat exchange, the heavy diesel oil is produced through the atmospheric pressure stripping tower production line 375.

[0077] The circulating heat extraction 77 of the middle section of the atmospheric tower is used to sequentially exchange heat between the liquid phase extracted from the middle section of the atmospheric tower and the reboiler 5 of the primary distillation tower, the heating system 25 of the vacuum tower and the reboiler 51 of the separation tower. The liquid phase extracted from the middle section of the atmospheric tower enters the reboiler 5 of the primary distillation tower as a heat source and performs a first-stage heat exchange with the materials in the primary distillation tower kettle; after the first-stage heat exchange, it enters the vacuum tower kettle heating system 25 as a heat source and performs a second-stage heat exchange with the materials in the vacuum tower kettle and the heating system 25; after the second-stage heat exchange, it enters the reboiler 51 of the separation tower as a heat source and performs a third-stage heat exchange with the reboiler 51 of the separation tower kettle; after the third-stage heat exchange, it returns to the atmospheric tower 2 after cooling, thereby making full use of the heat of the middle section of the atmospheric tower, saving energy and reducing the condensation amount at the top of the atmospheric tower 2; specifically, the circulating heat extraction 77 of the middle section of the atmospheric tower is used to sequentially exchange heat between the liquid phase extracted from the middle section of the atmospheric tower and the primary distillation tower kettle; The liquid phase extracted from the first section is heat exchanged with the reboiler 162 of the primary distillation tower, the heater 8126 of the negative pressure tower, the heater 119 of the negative pressure tower, and the reboiler 51 of the separation tower in sequence; the liquid phase extracted from the middle section of the atmospheric pressure tower is subjected to a first-stage heat exchange with the reboiler 162 of the primary distillation tower to provide heat for the reboiler 162 of the primary distillation tower; after the first-stage heat exchange, it is subjected to a second-stage primary heat exchange with the heater 8126 of the negative pressure tower to provide heat for the heater 8126 of the negative pressure tower; after the second-stage primary heat exchange, it is subjected to a second-stage secondary heat exchange with the heater 119 of the negative pressure tower to provide heat for the heater 119 of the negative pressure tower; after the second-stage secondary heat exchange, it is subjected to a third-stage heat exchange with the reboiler 51 of the separation tower to provide heat for the reboiler 51 of the separation tower; after the third-stage heat exchange and cooling, it is returned to the atmospheric pressure tower 2, thereby making full use of the heat of the middle section of the atmospheric pressure tower, saving energy, and reducing the condensation amount at the top of the atmospheric pressure tower 2.

[0078] The second-stage circulating heat extraction 96 in the middle section of the atmospheric pressure tower is used to sequentially exchange heat between the liquid phase extracted from the second stage of the atmospheric pressure tower and the second tower kettle heating system 95 of the negative pressure tower and the middle-stage circulating heating device 4 of the primary distillation tower. The liquid phase extracted from the second stage of the atmospheric pressure tower enters the second tower kettle heating system 95 of the negative pressure tower, and is used as the material and heat source of the tower kettle of the second negative pressure tower 24 to perform a primary heat exchange; after the primary heat exchange, it enters the middle-stage circulating heating device 4 of the primary distillation tower, and is used as a heat source to perform a secondary heat exchange with the circulating material in the middle section of the primary distillation tower. The liquid phase cooled by the secondary heat exchange is returned to the atmospheric pressure tower 2, which makes full use of the heat of the second-stage circulating heat extraction 96 in the middle section of the atmospheric pressure tower, further saving energy while reducing the condensation amount at the top of the atmospheric pressure tower 2; specifically, the atmospheric pressure tower The middle section second stage circulation heat extraction 96 is used to connect the liquid phase extracted from the middle section second stage of the atmospheric pressure tower with the negative pressure tower second heater nine 178, the negative pressure tower second heater two 171, and the primary distillation tower middle heater six 150 for heat exchange in sequence. The liquid phase collected from the middle section second stage of the atmospheric pressure tower undergoes a first-stage heat exchange with the negative pressure tower second heater nine 178 to provide heat for the negative pressure tower second heater nine 178, and after the first-stage heat exchange, undergoes a second-stage heat exchange with the negative pressure tower second heater two 171 to provide heat for the negative pressure tower second heater two 171, and after the first-stage secondary heat exchange, undergoes a second-stage heat exchange with the primary distillation tower middle heater six 150 to provide heat for the primary distillation tower middle heater six 150, and the liquid phase after the secondary heat exchange cooling is returned to the atmospheric pressure tower 2.

[0079] Embodiment nine:

[0080] This embodiment describes the heat utilization of the second-stage heat extraction 97 in the middle section of the vacuum tower, the third-stage heat extraction 98 in the middle section of the vacuum tower, the vacuum tower kettle, the vacuum three side line, the vacuum four side line, the vacuum five side line, and the vacuum six side line. The heat utilization of this embodiment does not require the use of a heat pump, which further achieves the effect of energy saving. Specifically:

[0081] The second-stage circulating heat extraction 97 of the middle section of the vacuum tower is used to sequentially exchange heat between the liquid phase extracted from the second stage of the middle section of the vacuum tower and the negative pressure tower first kettle heating system 25, the negative pressure tower second kettle heating system 95, the primary distillation tower reboiler 5, and the primary distillation tower middle section circulating heating device 4. The liquid phase extracted from the second stage of the middle section of the vacuum tower enters the negative pressure tower first kettle heating system 25, and is used as a heat source to exchange heat with the negative pressure tower first kettle material; after the first-stage heat exchange, it enters the negative pressure tower second kettle heating system 95, and is used as the negative pressure tower second kettle material and heat source. The first stage of the vacuum tower is heated by 200 ℃ and 800 ℃ of heating. The second stage of the vacuum tower is heated by 200 ℃ and 800 ℃ of heating. The second stage of the vacuum tower is heated by 200 ℃ and 800 ℃ of heating. The second stage of the vacuum tower is heated by 200 ℃ and 800 ℃ of heating. The second stage of the vacuum tower is heated by 200 ℃ and 800 ℃ of heating. The second stage of the vacuum tower is heated by 200 ℃ and 800 ℃ of heating. 175, negative pressure tower second heater one 170, primary distillation tower reboiler two 163, primary distillation tower middle heater seven 151 are sequentially heat exchanged, the liquid phase collected from the second section of the middle section of the vacuum tower is subjected to a primary heat exchange with negative pressure tower first heater six 124, providing heat for negative pressure tower first heater six 124, and after the primary primary heat exchange, it is subjected to a primary secondary heat exchange with negative pressure tower first heater three 121, providing heat for negative pressure tower first heater three 121, and after the primary secondary heat exchange, it is subjected to a secondary primary heat exchange with negative pressure tower second heater six 175 Heat exchange is performed to provide heat for the second heater 6 175 of the negative pressure tower. After the second-stage primary heat exchange, the second-stage secondary heat exchange is performed with the second heater 170 of the negative pressure tower to provide heat for the second heater 170 of the negative pressure tower. After the second-stage secondary heat exchange, the third-stage heat exchange is performed with the reboiler 2 163 of the primary distillation tower to provide heat for the reboiler 2 163 of the primary distillation tower. After the third-stage heat exchange, the fourth-stage heat exchange is performed with the middle heater 7 151 of the primary distillation tower to provide heat for the middle heater 7 151 of the primary distillation tower. The liquid phase cooled by the fourth-stage heat exchange is returned to the vacuum tower 3.

[0082] The three-stage circulating heat extraction 98 in the middle section of the vacuum tower is used to sequentially exchange heat between the liquid phase extracted from the three-stage middle section of the vacuum tower and the heating system 95 of the second tower kettle of the negative pressure tower. The liquid phase extracted from the three-stage middle section of the vacuum tower enters the heating system 95 of the second tower kettle of the negative pressure tower, and is used as the material and heat source of the second tower kettle of the negative pressure tower to perform a primary heat exchange. The liquid phase after heat exchange and cooling returns to the vacuum tower 3; specifically, the three-stage circulating heat extraction 98 in the middle section of the vacuum tower is used to sequentially exchange heat between the liquid phase extracted from the three-stage middle section of the vacuum tower and the second heater four 173 of the negative pressure tower and the second heater seven 176 of the negative pressure tower. The liquid phase extracted from the three-stage circulating heat extraction in the middle section of the vacuum tower performs a primary heat exchange with the second heater four 173 of the negative pressure tower to provide heat for the second heater four 173 of the negative pressure tower. After the primary heat exchange, it performs a secondary heat exchange with the second heater seven 176 of the negative pressure tower. The liquid phase after the primary and secondary heat exchange and cooling returns to the vacuum tower 3.

[0083] The vacuum residue oil extraction pipeline 92 of the vacuum tower kettle is connected with the vacuum tower kettle heating system 95 of the second vacuum tower, the reboiling device 5 of the primary distillation tower, the heating system 25 of the first vacuum tower kettle, the middle section circulating heating device 4 of the primary distillation tower, and the crude oil heating system 57 in sequence. The material extracted from the vacuum residue oil extraction pipeline 92 enters the vacuum tower kettle heating system 95 of the second vacuum tower, and is used as the kettle material and heat source of the second vacuum tower 24 to perform a primary heat exchange. After the primary heat exchange, it enters the primary distillation tower reboiling device 5, and is used as a heat source and the kettle material of the primary distillation tower to perform a secondary heat exchange. After the secondary heat exchange, it enters the vacuum tower kettle heating system 25 of the first vacuum tower, and is used as a heat source and the kettle material of the first vacuum tower to perform a tertiary heat exchange. After the tertiary heat exchange, it enters the middle section circulating heating device 4 of the primary distillation tower to perform a The heat source is used to circulate the material in the middle section of the primary distillation tower, and four-stage heat exchange is performed. After the four-stage heat exchange, it enters the crude oil heating system 57 and performs five-stage heat exchange with the crude oil in the crude oil heating system 57. After the five-stage heat exchange, the vacuum residue oil is produced through the vacuum residue oil production pipeline 92; more specifically, the vacuum residue oil production pipeline 92 is connected with the negative pressure tower second heater five 174, the negative pressure tower second heater ten 179, the primary distillation tower reboiler five 166, the negative pressure tower first heater fifteen 133, the negative pressure tower first heater eleven 129, the negative pressure tower first heater five 123, the negative pressure tower first heater two 120, the primary distillation tower middle heater four 148, and the crude oil heater twelve 114 in sequence, and the material produced by the vacuum residue oil production pipeline 92 is connected with the negative pressure tower second heater five 174, the negative pressure tower second heater ten 179, the primary distillation tower reboiler five 166, the negative pressure tower first heater fifteen 133, the negative pressure tower first heater eleven 129, the negative pressure tower first heater five 123, the negative pressure tower first heater two 120, the primary distillation tower middle heater four 148, and the crude oil heater twelve 114 The first stage heat exchange is performed with the first heater 174 of the negative pressure tower to provide heat for the second heater 174 of the negative pressure tower. After the first stage heat exchange, the first stage secondary heat exchange is performed with the second heater 179 of the negative pressure tower to provide heat for the second heater 179 of the negative pressure tower. After the first stage secondary heat exchange, the second stage heat exchange is performed with the reboiler 5 166 of the primary distillation tower to provide heat for the reboiler 5 166 of the primary distillation tower. After the secondary heat exchange, the third stage primary heat exchange is performed with the first heater 15 133 of the negative pressure tower to provide heat for the first heater 15 133 of the negative pressure tower. After the third stage primary heat exchange, the third stage secondary heat exchange is performed with the first heater 11 129 of the negative pressure tower to provide heat for the first heater 11 129 of the negative pressure tower. After the third stage secondary heat exchange, the first heater 123 of the negative pressure tower is heated. The three-stage three-time heat exchange provides heat for the negative pressure tower one heater five 123. After the three-stage three-time heat exchange, the three-stage four-time heat exchange is carried out with the negative pressure tower one heater two 120 to provide heat for the negative pressure tower one heater two 120. After the three-stage four-time heat exchange, the four-stage heat exchange is carried out with the primary distillation tower middle heater four 148 to provide heat for the primary distillation tower middle heater four 148. After the four-stage heat exchange, it enters the crude oil heater twelve 114 and carries out the five-stage heat exchange with the crude oil in the crude oil heater twelve 114 to provide heat for the crude oil heater twelve 114. After the five-stage heat exchange, the reduced residue oil is produced through the vacuum residue oil production pipeline 92. The vacuum tower two kettle heating system 95 carries out two heat exchanges, and the vacuum tower one kettle heating system 25 carries out four heat exchanges.

[0084] The three-line reduction side line 87 is connected with the negative pressure tower kettle heating system 25 and the primary distillation tower middle section circulating heating device 4 in sequence, and the material produced by the three-line reduction side line 87 enters the negative pressure tower kettle heating system 25, and is used as a heat source to perform a primary heat exchange with the negative pressure tower kettle material. After the primary heat exchange, it enters the primary distillation tower middle section circulating heating device 4, and is used as a heat source to perform a secondary heat exchange with the primary distillation tower middle section circulating material. After the secondary heat exchange, the three-line reduction oil is produced through the three-line reduction side line 87; specifically, the three-line reduction side line 87 is connected with the negative pressure tower heater nine 127 and the primary distillation tower middle heater five 149 in sequence, and the material produced by the three-line reduction side line 87 performs a primary heat exchange with the negative pressure tower heater nine 127 to provide heat for the negative pressure tower heater nine 127, and performs a secondary heat exchange with the primary distillation tower middle heater five 149 to provide heat for the primary distillation tower middle heater five 149. After the secondary heat exchange, the three-line reduction oil is produced through the three-line reduction side line 87.

[0085] The four-line reduction side line 88 is connected to the negative pressure tower-tower heating system 25, the primary distillation tower reboiling device 5, and the primary distillation tower middle section circulating heating device 4 in sequence. The material produced by the four-line reduction side line 88 enters the negative pressure tower-tower heating system 25, and is used as a heat source to perform a first-stage heat exchange with the negative pressure tower-tower material. After the first-stage heat exchange, it enters the primary distillation tower reboiling device 5, and is used as the primary distillation tower kettle material and heat source to perform a second-stage heat exchange. After the second-stage heat exchange, it enters the primary distillation tower middle section circulating heating device 4, and is used as a heat source to perform a third-stage heat exchange with the primary distillation tower middle section circulating material. After the third-stage heat exchange, the four-line reduction oil is produced through the four-line reduction side line 88; specifically, The side line 88 of the reduction four is connected with the negative pressure tower heater four 122, the primary distillation tower reboiler six 167, and the primary distillation tower middle heater nine 153 in sequence. The material produced by the side line 88 of the reduction four undergoes a primary heat exchange with the negative pressure tower heater four 122 to provide heat for the negative pressure tower heater four 122. After the primary heat exchange, the material undergoes a secondary heat exchange with the primary distillation tower reboiler six 167 to provide heat for the primary distillation tower reboiler six 167. After the secondary heat exchange, the material undergoes a tertiary heat exchange with the primary distillation tower middle heater nine 163 to provide heat for the primary distillation tower middle heater nine 163. After the tertiary heat exchange, the reduction four line oil is produced through the side line 88 of the reduction four.

[0086] The five-reduction side line 89 is connected with the vacuum tower second kettle heating system 95, the vacuum tower first kettle heating system 25, and the primary distillation tower middle section circulating heating device 4 in sequence. The material extracted from the five-reduction side line 89 enters the vacuum tower second kettle heating system 95, and is used as a heat source to perform a primary heat exchange with the vacuum tower second 24 kettle material. After the primary heat exchange, it enters the vacuum tower first kettle heating system 25, and is used as a heat source to perform a secondary heat exchange with the vacuum tower first 16 kettle material. After the secondary heat exchange, it enters the primary distillation tower middle section circulating heating device 4, and is used as a heat source to perform a tertiary heat exchange with the primary distillation tower middle section circulating material. After the tertiary heat exchange, the five-reduction oil is extracted through the five-reduction side line 89. Specifically, the fifth-reduction side line 89 is connected with the negative pressure tower second heater three 172, the negative pressure tower first heater thirteen 131, and the primary distillation tower middle heater two 146 in sequence; the material produced by the fifth-reduction side line 89 undergoes a primary heat exchange with the negative pressure tower second heater three 172 to provide heat for the negative pressure tower second heater three 172; after the primary heat exchange, it undergoes a secondary heat exchange with the negative pressure tower first heater thirteen 131 to provide heat for the negative pressure tower first heater thirteen 131; after the secondary heat exchange, it undergoes a tertiary heat exchange with the primary distillation tower middle heater two 146 to provide heat for the primary distillation tower middle heater two 146; after the tertiary heat exchange, the fifth-reduction oil is produced through the fifth-reduction side line 89.

[0087] The hexachlorobenzene side line 91 is connected in sequence with the vacuum tower second kettle heating system 95, the primary distillation tower reboiling device 5, the vacuum tower first kettle heating system 25, and the primary distillation tower middle section circulating heating device 4. The material extracted from the hexachlorobenzene side line 91 enters the vacuum tower second kettle heating system 95, and is used as a heat source to perform a primary heat exchange with the vacuum tower second 24 kettle material. After the primary heat exchange, it enters the primary distillation tower reboiling device 5, and is used as a heat source to perform a secondary heat exchange with the primary distillation tower kettle material. After the secondary heat exchange, it enters the vacuum tower first kettle heating system 25, and is used as a heat source to perform a tertiary heat exchange with the vacuum tower first 16 kettle material. After the tertiary heat exchange, it enters the primary distillation tower middle section circulating heating device 4, and is used as a heat source to perform a quaternary heat exchange with the primary distillation tower middle section circulating material. After the quaternary heat exchange, hexachlorobenzene oil is extracted through the hexachlorobenzene side line 91. Body: The six-reduction side line 91 is connected with the negative pressure tower second heater eight 177, the primary distillation tower reboiler four 165, the negative pressure tower first heater ten 128, and the primary distillation tower middle heater three 147 in sequence; the material produced by the six-reduction side line 91 undergoes a primary heat exchange with the negative pressure tower second heater eight 177 to provide heat for the negative pressure tower second heater eight 177; after the primary heat exchange, it undergoes a secondary heat exchange with the primary distillation tower reboiler four 165 to provide heat for the primary distillation tower reboiler four 165; after the secondary heat exchange, it undergoes a tertiary heat exchange with the negative pressure tower first heater ten 128 to provide heat for the negative pressure tower first heater ten 128; after the tertiary heat exchange, it undergoes a quaternary heat exchange with the primary distillation tower middle heater three 147 to provide heat for the primary distillation tower middle heater three 147; after the fourth stage heat exchange, six-reduction line oil is produced through the six-reduction side line 91.

[0088] Embodiment ten:

[0089] This embodiment provides a specific application scenario, specifically:

[0090] Taking an 8 million tons / year atmospheric and vacuum distillation unit of a certain refinery as an example, under the same processing capacity and total extraction rate, the heat load of the conventional atmospheric furnace is 69.9MW, and the heat load of the vacuum furnace is 28.5MW; after adopting the present invention, the heat load of the atmospheric furnace is 59.2MW, and the heat load of the vacuum furnace is 30.0MW, and the total heat load of the heating furnace is reduced by about 9%, which plays a role in energy saving.

[0091] The working principle of the present application is as follows: crude oil enters the desalting tank 52 for desalting and dehydration, and then is heated. The heated material passes through the flash tank 54 for flash evaporation, and the liquid phase enters the primary distillation tower 1. The gas phase after flash evaporation is condensed by the condenser and enters the secondary flash tank 61 for secondary flash evaporation. The gas phase after the secondary flash evaporation is extracted through the non-condensable gas pipeline 64, and the liquid phase after the secondary flash evaporation enters the naphtha separation device for naphtha extraction; the top of the primary distillation tower 1 is provided with a tower top reflux, and the crude oil from the primary distillation tower 1 is extracted. The top gas and light gasoline of the primary distillation tower, the light gasoline enters the naphtha separation device for naphtha production; the bottom oil of the primary distillation tower 1 enters the negative pressure tower 16, the gas phase at the top of the negative pressure tower 16 is partially refluxed to the negative pressure tower 16 after condensation, and partially enters the naphtha separation device for naphtha separation, the material at the bottom of the negative pressure tower 16 is heated and enters the negative pressure tower 24, the gas phase at the top of the negative pressure tower 24 is partially refluxed to the negative pressure tower 24 after condensation, and partially enters the naphtha separation device for naphtha separation. The separation device is used to separate naphtha. The negative pressure stripping tower 31 produces kerosene after steam stripping. The bottom oil at the bottom of the negative pressure tower 24 is heated by the atmospheric pressure heating furnace 36 and then enters the atmospheric pressure tower 2. The gas phase at the top of the atmospheric pressure tower 2 is condensed and refluxed to the atmospheric pressure tower 2. The atmospheric pressure tower is equipped with three side lines. The atmospheric pressure stripping tower production pipeline 1 73, the atmospheric pressure stripping tower production pipeline 2 74, and the atmospheric pressure stripping tower production pipeline 3 75 are stripped by stripping steam in the atmospheric pressure stripping tower 66 to produce kerosene and light oil respectively. Diesel, heavy diesel; the bottom oil of the atmospheric tower 2 is heated by the pressure reducing heating furnace 38 and then enters the pressure reducing tower 3. The top of the pressure reducing tower 3 is provided with a condensed oil production device. The steam injection device 80 extracts the top gas of the pressure reducing tower 3 and maintains the vacuum degree of the top. The top of the pressure reducing tower 3 produces condensed oil and water; the bottom of the pressure reducing tower 3 produces residual oil, the pressure reducing tower 3 produces the first-line oil and the sixth-line oil, and the pressure reducing stripping tower 83 is stripped by the stripping steam to produce the second-line oil, the third-line oil, the fourth-line oil and the fifth-line oil respectively.

[0092] In summary, due to the adoption of the above technical solution, the present application has the following advantages:

[0093] 1. All gasoline components and part of kerosene components of crude oil can be extracted before entering the atmospheric pressure tower, which reduces energy consumption, improves heat utilization rate, and improves crude oil separation accuracy;

[0094] 2. Adding two negative pressure towers between the primary distillation tower and the atmospheric pressure tower can separate the vaporized gasoline and kerosene components in time, reduce the irreversibility of heating and cooling, and achieve the purpose of energy saving; and the two negative pressure towers adopt negative pressure operation, which reduces the operating temperature in the negative pressure tower and is conducive to the utilization of low-grade heat in the system;

[0095] 3. Two negative pressure towers extract all gasoline components and part of kerosene components, reducing the amount of materials entering the atmospheric pressure heating furnace, reducing the load of the atmospheric pressure heating furnace, directly reducing the fuel oil consumption of the device, and further achieving the purpose of energy saving;

[0096] 4. The operating pressure of the primary distillation tower is reduced to between slightly positive pressure and slightly negative pressure, and the circulating heating in the middle section of the primary distillation tower is increased to reduce the heat grade required by the primary distillation tower and increase the energy utilization efficiency;

[0097] 5. After the crude oil is heated by the heat exchange network, a flash tank is added before it enters the primary distillation tower. The flash tank can be divided into two or more stages. The operating pressure of the flash tank is higher than that of the primary distillation tower, which can reduce the amount of non-condensable gas and reduce the gas loss in the primary distillation tower;

[0098] 6. Make full use of the heat from the top, middle section and production pipeline of each tower. Only the atmospheric pressure tower and the vacuum tower require external heat sources. The heat sources of the rest of the towers use the heat of the device itself and do not require heat pumps, which improves the utilization rate of heat and further achieves energy-saving effects.

[0099] The preferred embodiments of the present application are described in detail above in conjunction with the accompanying drawings; however, the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, a variety of simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the protection scope of the present application.

[0100] In addition, the various implementation modes of the present application may be arbitrarily combined, and as long as they do not violate the concept of the present application, they should also be regarded as the contents disclosed in the present application.

Claims

1. A five-tower atmospheric and vacuum distillation device with energy-saving effect, comprising a primary distillation tower (1), an atmospheric pressure tower (2), and a vacuum tower (3), wherein a primary distillation tower reboiler (5) is provided at the bottom of the primary distillation tower (1), a primary distillation tower reflux device is connected to the top of the primary distillation tower (1), a atmospheric pressure tower (2) is connected to the top of the atmospheric pressure tower reflux device, a feeding device is provided at the front of the primary distillation tower (1), and a negative pressure tower is provided between the primary distillation tower (1) and the atmospheric pressure tower (2), characterized in that: The negative pressure tower comprises a negative pressure tower 1 (16) connected to a primary distillation tower (1), a negative pressure tower 1 reflux device is connected to the top of the negative pressure tower 1 (16), a negative pressure tower 1 reboiler (22) is arranged at the middle and lower part of the negative pressure tower 1 (16), the negative pressure tower 1 (16) is connected to a negative pressure tower 2 (24) via a pipeline (23), a negative pressure tower 1 kettle heating system (25) is arranged on the pipeline (23), a negative pressure tower 2 reflux device is connected to the top of the negative pressure tower 2 (24), the pressure of the negative pressure tower 1 (16) is higher than the pressure of the negative pressure tower 2 (24), the bottom of the negative pressure tower 2 (24) is connected to the middle and lower part of the atmospheric pressure tower (2), and a negative pressure tower 2 kettle heating system (95) is arranged between the negative pressure tower 2 (24) and the atmospheric pressure tower (2).

2. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 1, characterized in that: At least one of the primary distillation tower reflux device, the negative pressure tower first reflux device, and the negative pressure tower second reflux device is connected to a naphtha separation device; the naphtha separation device comprises a naphtha separation tower feed buffer tank (39), the naphtha separation tower feed buffer tank (39) is connected to a naphtha separation tower (41), a naphtha separation tower reflux device is arranged at the top of the naphtha separation tower (41), the naphtha separation tower reflux device is connected to a light naphtha production pipeline (44), and a heavy naphtha production pipeline (45) is arranged at the bottom of the naphtha separation tower (41).

3. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 2, characterized in that: The feeding device comprises a crude oil feed pipeline (50) connected to a desalting tank (52), and a crude oil feed pump (56) and a crude oil heating system (57) are arranged on the crude oil feed pipeline (50); the desalting tank (52) is connected to a flash tank (54) via a crude oil feed pipeline (53), and the flash tank (54) is connected to a primary distillation tower (1) via a crude oil feed pipeline (55).

4. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 3, characterized in that: The top of the flash tank (54) is connected to the secondary flash tank (61), the bottom of the secondary flash tank (61) is connected to the naphtha separation tower feed buffer tank (39) through the secondary flash tank pipeline (62), and the top of the secondary flash tank (61) is connected to the non-condensable gas pipeline (64).

5. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 3, characterized in that: The atmospheric pressure tower (2) is connected to the atmospheric pressure stripping tower (66), and one side of the atmospheric pressure stripping tower (66) is connected to an atmospheric pressure stripping tower production pipeline 1 (73), an atmospheric pressure stripping tower production pipeline 2 (74), and an atmospheric pressure stripping tower production pipeline 3 (75); one side of the vacuum stripping tower (3) is connected to a vacuum stripping tower (83), and one side of the vacuum stripping tower (83) is connected to a vacuum stripping tower 2 side line (86), a vacuum stripping tower 3 side line (87), a vacuum stripping tower 4 side line (88), and a vacuum stripping tower 5 side line (89); the upper part of the vacuum stripping tower 2 side line (86) is connected to a vacuum stripping tower 1 side line (90) on the vacuum stripping tower (3), the lower part of the vacuum stripping tower 5 side line (89) is connected to a vacuum stripping tower 6 side line (91) on the vacuum stripping tower (3), and the bottom of the vacuum stripping tower (3) is connected to a vacuum residue oil production pipeline (92).

6. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 5, characterized in that: The crude oil heating system (57) is respectively connected to the top of the primary distillation tower (1), the top of the atmospheric pressure tower (2), the top of the negative pressure tower 1 (16), and the top of the negative pressure tower 2 (24); the gas phase at the top of the primary distillation tower (1), the gas phase at the top of the atmospheric pressure tower (2), the gas phase at the top of the negative pressure tower 1 (16), and the gas phase at the top of the negative pressure tower 2 (24) respectively exchange heat with the crude oil in the crude oil heating system (57), thereby providing heat for the crude oil heating system (57).

7. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 6, characterized in that: A negative pressure tower 2 middle section circulation heat extraction (94) is arranged in the middle of the negative pressure tower 2 (24).

8. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 7, characterized in that: The negative pressure tower second middle section circulating heat extraction (94) is used to exchange heat between the liquid phase extracted from the negative pressure tower second middle section and the crude oil in the crude oil heating system (57).

9. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 8, characterized in that: The middle section of the primary distillation tower (1) is provided with a primary distillation tower middle section circulation heating device (4).

10. The energy-saving five-tower atmospheric and vacuum distillation apparatus according to claim 9, characterized in that: The atmospheric stripping tower extraction pipeline 1 (73) is connected to the negative pressure tower kettle heating system (25), and the negative pressure tower kettle heating system (25) is connected to the primary distillation tower middle section circulation heating device (4). The material extracted from the atmospheric stripping tower extraction pipeline 1 (73) undergoes primary heat exchange with the negative pressure tower kettle heating system (25), and then undergoes secondary heat exchange with the primary distillation tower middle section circulation heating device (4). The atmospheric stripping tower extraction pipeline 2 (74) is connected to the negative pressure tower kettle heating system (25), and the negative pressure tower kettle heating system (25) is connected to the naphtha fractionation tower raw material heater (43). The material extracted from the atmospheric stripping tower extraction pipeline 2 (74) is subjected to primary heat exchange with the negative pressure tower kettle heating system (25), and then subjected to secondary heat exchange with the naphtha fractionation tower raw material heater (43). The atmospheric stripping tower extraction pipeline three (75) is connected to the negative pressure tower-tower kettle heating system (25), the negative pressure tower-tower kettle heating system (25) is connected to the primary distillation tower reboiling device (5), and the primary distillation tower reboiling device (5) is connected to the primary distillation tower middle section circulation heating device (4); the material extracted from the atmospheric stripping tower extraction pipeline three (75) is subjected to primary heat exchange with the negative pressure tower-tower kettle heating system (25), and after the primary heat exchange, is subjected to secondary heat exchange with the primary distillation tower reboiling device (5), and after the secondary heat exchange, is subjected to tertiary heat exchange with the primary distillation tower middle section circulation heating device (4); The three-reduction side line (87) is connected to the negative pressure tower-tower heating system (25), and the negative pressure tower-tower heating system (25) is connected to the primary distillation tower middle section circulation heating device (4). The material extracted from the three-reduction side line (87) is subjected to primary heat exchange with the negative pressure tower-tower heating system (25), and after the primary heat exchange, is subjected to secondary heat exchange with the primary distillation tower middle section circulation heating device (4); The four-stage reduction side line (88) is connected to the negative pressure tower-tower heating system (25), the negative pressure tower-tower heating system (25) is connected to the primary distillation tower reboiling device (5), the primary distillation tower reboiling device (5) is connected to the primary distillation tower middle section circulation heating device (4), the material extracted from the four-stage reduction side line (88) is subjected to a primary heat exchange with the negative pressure tower-tower heating system (25), after the primary heat exchange, it is subjected to a secondary heat exchange with the primary distillation tower reboiling device (5), after the secondary heat exchange, it is subjected to a tertiary heat exchange with the primary distillation tower middle section circulation heating device (4), and after the tertiary heat exchange, the four-stage reduction oil is extracted through the four-stage reduction side line (88); The five-reduction side line (89) is connected to the negative pressure tower second kettle heating system (95), the negative pressure tower second kettle heating system (95) is connected to the negative pressure tower first kettle heating system (25), the negative pressure tower first kettle heating system (25) is connected to the primary distillation tower middle section circulation heating device (4), the material extracted from the five-reduction side line (89) is subjected to primary heat exchange with the negative pressure tower second kettle heating system (95), after the primary heat exchange, it is subjected to secondary heat exchange with the negative pressure tower first kettle heating system (25), and after the secondary heat exchange, it is subjected to tertiary heat exchange with the primary distillation tower middle section circulation heating device (4); The hexahydrogen reduction side line (91) is connected to the second tower kettle heating system (95) of the negative pressure tower, the reboiling device (5) of the primary distillation tower, the first tower kettle heating system (25) of the negative pressure tower, and the middle section circulating heating device (4) of the primary distillation tower in sequence; the material extracted from the hexahydrogen reduction side line (91) undergoes a primary heat exchange with the second tower kettle heating system (95) of the negative pressure tower, and after the primary heat exchange, undergoes a secondary heat exchange with the reboiling device (5) of the primary distillation tower, and after the secondary heat exchange, undergoes a tertiary heat exchange with the first tower kettle heating system (25) of the negative pressure tower, and after the tertiary heat exchange, undergoes a quaternary heat exchange with the middle section circulating heating device (4) of the primary distillation tower; The vacuum residue oil production pipeline (92) is connected to the vacuum tower second kettle heating system (95), the primary distillation tower reboiling device (5), the vacuum tower first kettle heating system (25), the primary distillation tower middle section circulating heating device (4), and the crude oil heating system (57) in sequence. The material produced by the vacuum residue oil production pipeline (92) undergoes a primary heat exchange with the vacuum tower second kettle heating system (95), undergoes a secondary heat exchange with the primary distillation tower reboiling device (5) after the primary heat exchange, undergoes a tertiary heat exchange with the vacuum tower first kettle heating system (25) after the secondary heat exchange, undergoes a quaternary heat exchange with the primary distillation tower middle section circulating heating device (4) after the tertiary heat exchange, enters the crude oil heating system (57) after the quaternary heat exchange, and undergoes a quinary heat exchange with the crude oil in the crude oil heating system (57).

Images