CN107057747B - Atmospheric-vacuum energy-saving deep drawing process based on clear cutting - Google Patents

Abstract

An atmospheric-vacuum high-efficiency energy-saving deep drawing process based on clear cutting is characterized in that after first-stage heat exchange, crude oil passes through a deep drawing stripping tower plate added at the bottom of a primary distillation tower to reduce the fraction of the primary distillation tower bottom oil below the primary distillation feeding temperature to less than 1% -3%, and after second-stage heat exchange, the primary distillation tower bottom oil passes through an atmospheric-pressure furnace front additional flash tower to reduce the fraction content of the primary distillation tower bottom oil below the primary distillation feeding temperature to less than 3% -5%; the flash oil is pumped into a normal pressure furnace and heated to 365-390 ℃ and then enters a normal pressure tower for separation; the initial boiling point of the heavy diesel is controlled to be more than 360 ℃ and the initial boiling point and 98 percent of the second-line diesel form a void degree of more than 5 ℃ through the desuperheating rectification section and the circulating reflux separation of partial thermogravimetric heavy diesel, and the atmospheric residue reduces the fraction of the atmospheric residue below 365 ℃ to be less than 2 percent through adding a deep-drawing stripping tower plate at the bottom of the atmospheric residue; the micro-wet distillation of the vacuum residuum by adding a deep-drawing stripping tower plate at the bottom of the vacuum tower reduces the fraction of the vacuum residuum below the cut point to less than 5 percent.

Description

Atmospheric-vacuum energy-saving deep drawing process based on clear cutting

1. Field of the invention

The invention provides an atmospheric and vacuum energy-saving deep drawing process based on clear cutting, and relates to the field of petroleum refining.

2. Background of the invention

The atmospheric and vacuum distillation device is a faucet device of an oil refinery and also a basic device for deep processing, and directly influences the comprehensive benefit of the whole refinery.

With the heavy and inferior crude oil and the mass production of unconventional heavy and inferior oil such as shale oil, oil sand oil, heavy (thick) oil, extra heavy oil, deep petroleum, asphalt, coal tar and the like in the future, the atmospheric residue is difficult to be directly used as a heavy oil catalytic cracking raw material. The method has the advantages that the vacuum extraction rate is improved, more catalytic cracking or hydrocracking raw materials are strived for, and the yield of the residual oil is reduced, so that the inevitable choices of oil refining enterprises for comprehensively optimizing downstream coking and catalytic cracking or hydrocracking device production, maximally utilizing resources and improving benefits are provided. The distillate oil of deep vacuum distillation is mainly used as a catalytic cracking or hydrocracking raw material, and the benefit is reflected on the device, more importantly, the comprehensive benefit of downstream catalytic cracking, hydrocracking and coking devices and the whole refinery. Therefore, the importance and the benefit of the pressure reducing deep drawing technology are more prominent, and the pressure reducing deep drawing technology and related equipment are actively researched and developed at home and abroad.

At present, the existing pressure reduction deep drawing technology at home and abroad is only developed through the research idea of improving the vacuum degree and the feeding temperature of a flash evaporation section in a pressure reduction tower part, but not from the design and the development of an atmospheric and vacuum pressure reduction integral device system, and the depth and the energy consumption of pressure reduction deep drawing also have larger promotion space. For example, the Mobil petroleum company Deep Cutting Vacuum Distillation (DCVD) technology is a patented fractionation device which forms liquid phase de-entrainment through direction change, has no vapor-liquid contact, no re-entrainment, 133.3Pa of differential pressure and no fractionation function and is used for de-entrainment of a riser in a flash evaporation section of a vacuum tower, reduces liquid residual oil entrainment and simultaneously enables the flash evaporation section of the vacuum tower to reach the lowest pressure and the highest temperature, thereby improving the yield of vacuum distillate oil and the accurate separation of the distillate oil. The direct contact heat transfer technology is successfully applied to the two-stage reduction and the three-stage reduction of the fuel type vacuum tower abroad to reduce the pressure drop of the vacuum tower, so that the flash evaporation section of the vacuum tower reaches the lowest pressure to improve the yield of vacuum distillate oil. The pressure reduction deep drawing test of the United states Stats engineering company by using light Bronsted crude oil and heavy Arabian crude oil shows that the flash evaporation section pressure of the pressure reduction tower and the total pressure drop of the whole tower have great influence on the operation of the tower and the product yield. When the temperature of the flash section is unchanged at 399 ℃, the operating pressure of the flash section is reduced from 100mmHg to 15mmHg, so that the yield of the Arabian heavy poise vacuum residue is reduced from 37 percent to 25 percent, and the extraction rate is improved by 12 percent. The Netherlands Shell company adopts a deep flash evaporation High Vacuum Unit (HVU) technology, so that the pressure drop of the whole tower is only 0.4kPa, and the cutting temperature of the true boiling point reaches 585 ℃.

For the atmospheric and vacuum distillation device requiring deep vacuum distillation, the primary distillation tower and the atmospheric tower select equipment, design process flow and operation parameters according to the technical idea of producing straight-run gasoline and diesel. If the stripping section of the primary distillation tower is not provided with steam stripping, the heat exchange effect of the second section is influenced; after the two-stage heat exchange, the raw material is not separated from a vapor phase and directly enters the normal pressure furnace, so that the heat load and the pressure drop of the normal pressure furnace are increased, and the heat exchange efficiency of a heating furnace tube of the normal pressure furnace is reduced; the outlet temperature of the atmospheric furnace is not more than 365 ℃, the separation effect of the stripping section at the bottom of the large atmospheric tower is extremely poor, the content of the front fraction at 350 ℃ is more than 7%, the existence of the light fractions increases the heat load and the pressure drop of the vacuum furnace and the heat exchange efficiency of the heating furnace tube, and also increases the temperature drop and the pressure drop of the vacuum oil transfer line, thereby reducing the feeding temperature and the gasification rate of the vacuum flash evaporation section and influencing the vacuum deep drawing effect.

At present, in the aspect of pressure reduction and deep drawing, certain difference exists between China and abroad, the domestic pressure reduction cutting point is mostly about 540 ℃, the difference is larger than that between 580 and 610 ℃ at abroad, and the energy consumption is higher by more than 15%. The outlet temperature of the vacuum furnace for producing the lubricating raw material in China is not more than 400 ℃, and the outlet temperature of the vacuum furnace for producing the cracking raw material is not more than 410 ℃. The temperature of the oil transfer line is generally reduced by about 10-25 ℃, the temperature of the feeding section of the reduced pressure distillation system can reach 385-400 ℃ in fuel type, and the temperature of the lubricating oil type can reach 375-390 ℃. The real boiling point cutting temperature of domestic vacuum residue is mostly below 540 ℃, and some are below 520 ℃. In foreign countries, the real boiling point cutting point of vacuum residue has been set at 565 ℃, and some cutting points are even set at more than 600 ℃, for example, the deep cutting technology of crude oil by KBC in the United states enables the cutting point of vacuum distillation to reach 607-621 ℃.

In addition, home and abroad atmospheric pressure reduction device is not clear in oil product cutting at the bottoms of the primary distillation tower, the atmospheric tower and the vacuum tower, and although deep drawing is realized and the cutting point is improved, high-quality diesel oil and wax oil have large improving range, the distillation energy consumption is reduced, the potential can be dug, and the atmospheric pressure reduction device and the whole refinery economic benefit are to be improved urgently. For example, in order to achieve the purpose of deep drawing under reduced pressure, KBC company in America increases the heat exchange quantity of middle-section reflux of heavy distillate oil and crude oil under the condition that the fuel quantity of an atmospheric furnace is not changed, and improves the flash evaporation temperature and the cutting depth of an atmospheric tower, thereby reducing the load of the vacuum tower; and a small amount of steam is injected to increase the cutting point of the vacuum tower to about 571 ℃, which is 33 ℃ higher than the original cutting point, and the catalytic cracking raw materials are added, so that the vacuum deep drawing potential from the whole atmospheric and vacuum device is huge.

In conclusion, it is urgently needed to select equipment, system optimization design process flow and operation parameters from the whole atmospheric and vacuum pressure reduction integrated device according to the deep drawing requirements of the vacuum pressure reduction system, develop a new efficient and energy-saving vacuum deep drawing technology, and meet the development trend of petroleum refining in the future.

3. Summary of the invention

The invention aims to overcome the defects of the deep drawing technology of the conventional atmospheric and vacuum distillation device, and provides an atmospheric and vacuum high-efficiency energy-saving deep drawing process based on clear cutting, which improves the yield of high-quality diesel oil and wax oil, reduces the energy consumption of atmospheric and vacuum distillation deep drawing, and provides qualified raw materials for downstream catalytic cracking, hydrocracking and coking devices, thereby improving the economic benefit of the whole refinery.

The technical scheme of the invention is as follows:

the invention provides an atmospheric and vacuum high-efficiency energy-saving deep drawing process based on clear cutting, which is characterized in that a stripping tower plate is adopted at the bottom of each atmospheric and vacuum tower, an atmospheric furnace front flash tower is additionally arranged, the outlet temperature of an atmospheric furnace and the cutting temperature of atmospheric residue are increased, and operating parameters, a heat exchange process and high-efficiency separation equipment are reasonably designed, so that the cutting definition of oil products at the bottoms of a primary distillation tower, an atmospheric tower and a vacuum tower is improved, and the deep drawing aims of improving the yield of high-quality diesel oil and wax oil and reducing the distillation energy consumption are fulfilled. The method is characterized in that the crude oil is sequentially subjected to first-stage heat exchange with first-line diesel oil, first-line wax reducing oil, second-line diesel oil, second-line wax reducing oil, heavy diesel oil after primary replacement, third-line wax reducing oil after primary replacement and vacuum residue oil after primary replacement; the crude oil enters a flash evaporation section of a primary distillation tower after heat exchange at the temperature of 180-240 ℃, the vapor phase is defoamed and then enters a rectification section of the primary distillation tower to be separated to obtain straight-run gasoline and light diesel oil, the liquid phase is subjected to enhanced steam stripping by less than 1% of superheated steam through a deep-drawing stripping tower plate added at the bottom of the primary distillation tower, and the content of fractions in the tower bottom oil before the temperature is lower than the primary distillation feeding temperature is reduced to be less than 1% -3%; the bottom oil of the primary distillation tower sequentially carries out second-stage heat exchange with heavy diesel oil, third-line wax reducing oil and vacuum residue oil; after the second-stage heat exchange, the bottom oil of the primary tower is subjected to oil-gas separation by adding a flash tower in front of the atmospheric tower at 300-360 ℃, the content of distillate in the liquid phase oil is reduced to 1-5% to reduce the load of the atmospheric tower before the temperature is lower than the second-stage heat exchange, and the flash steam is defoamed and then is directly introduced into a heavy diesel stripping return tower opening of the atmospheric tower; the flash oil is sent into an atmospheric furnace through a flash pump to be heated to 365-390 ℃ and then enters a flash section of the atmospheric tower for oil-gas separation, the liquid phase is subjected to enhanced steam stripping by using less than 1% of superheated steam through a deep-drawing stripping tower plate added at the bottom of the atmospheric tower, the content of fractions in the atmospheric residue below 365 ℃ is reduced to be less than 2% so as to reduce the load of a vacuum furnace, a vacuum oil transfer line and a vacuum tower, the vapor phase is subjected to heat exchange and rectification separation with partial cycle reflux thermogravimetric diesel oil through a desuperheating rectification section arranged at the upper part of the flash section after foam removal, the initial distillation point of the heavy diesel oil is controlled to be more than 360 ℃, the heavy diesel oil and 98% of a second-line diesel oil fraction form a desuperheating degree of more than 5 ℃, and the vapor phase is further; the method comprises the following steps that (1) atmospheric residue is directly heated to 390-420 ℃ through a vacuum furnace and then enters a flash evaporation section of a vacuum tower for oil-gas separation, the liquid phase is subjected to micro wet distillation by using 0.01-0.2% superheated steam through a deep-drawing stripping tower plate added at the bottom of the vacuum tower, the content of fractions below a cutting point in the vacuum residue is reduced to be less than 5%, the vacuum residue is pumped out through an atmospheric leg of the vacuum tower and is sent out with a raw oil after primary and secondary heat exchange, vapor phase is defoamed and then is subjected to three-section condensation and rectification separation through the vacuum tower, and a three-line reduced wax oil, a two-line reduced wax oil and a one-line reduced wax oil are; and cooling the gas at the top of the pressure reduction tower by a cooler to obtain pressure reduction condensate oil and pressure reduction dry gas, and pumping the pressure reduction dry gas out by a pressure reduction vacuum pump.

Wherein, the deep-drawing stripping column plate is a fixed guide strip valve column plate, the opening rate of the plate surface is 0.5-3%, and the opening point is increased by more than 50% compared with the common rectification column plate; the two ends of the fixed strip valve are fixed with the plate surface, and the side surface is provided with holes, and the height of the strip seam is only 0.5-2 mm; the flash evaporation sections of the primary distillation tower, the atmospheric tower, the flash evaporation tower and the vacuum tower are all provided with foam removers, and the stripping section is all provided with deep-drawing stripping tower plates.

The present invention will be described in detail with reference to examples.

4. Description of the drawings

The attached drawing is a process schematic diagram of the invention.

The drawings of the drawings are illustrated below:

1. the system comprises a heat exchanger 12, a heat exchanger 23, a heat exchanger 34, a heat exchanger 45, a heat exchanger 56, a heat exchanger 67, a heat exchanger 78, a flash tower 9, straight run gasoline, 10, light diesel oil 11, a heat exchanger 1112, a heat exchanger 1213, a heat exchanger 1314, a flash tower 15, an atmospheric furnace 16, an atmospheric tower 17, a desuperheating rectification section 18, gasoline 19, first line diesel oil 20, second line diesel oil 21, a vacuum furnace 22, a vacuum oil transfer line 23, a vacuum tower 24, vacuum residue oil 25, third line wax reducing oil 26, second line wax reducing oil 27, first line wax reducing oil 28, vacuum condensate oil 29, a vacuum pump 30 and a deep-drawing stripping tray.

The process features of the present invention are described in detail below with reference to the accompanying drawings and examples.

5. Detailed description of the preferred embodiments

In the embodiment of the method, the first step,

the victory crude oil is sequentially subjected to first-stage heat exchange with first-line diesel oil, first-line wax oil reduction, second-line diesel oil, second-line wax oil reduction, first-stage after-exchange heavy diesel oil, first-stage after-exchange third-line wax oil and first-stage after-exchange vacuum residue oil through a heat exchanger 1 to a heat exchanger 7, and is preheated to 180-240 ℃; crude oil enters a flash evaporation section of a primary distillation tower (8) after heat exchange, vapor phase is defoamed and then enters a rectification section of the primary distillation tower (8) to be separated to obtain straight-run gasoline (9) and light diesel oil (10), the liquid phase passes through a deep-drawing stripping tower plate (30) additionally arranged at the bottom of the primary distillation tower (8) and is subjected to enhanced stripping by less than 1% of superheated steam, and the content of fractions in the bottom oil before the temperature is lower than the primary-run feeding temperature is reduced to be less than 1% -3%; the bottom oil of the preliminary distillation tower (8) passes through a heat exchanger 11 to a heat exchanger 13 to perform second-stage heat exchange with the heavy diesel oil, the third-line wax reducing oil and the vacuum residue oil in sequence, and the temperature after the second-stage heat exchange is 300-360 ℃; after the second-stage heat exchange, the bottom oil of the primary tower (8) passes through a flash tower (14) added in front of the atmospheric furnace (15) to carry out oil-gas separation, the content of distillate in the liquid phase oil at the temperature lower than that after the second-stage heat exchange is reduced to 1-5% again to reduce the load of the atmospheric furnace (15), and the flash steam is defoamed and then is directly introduced into a heavy diesel stripping return tower port of the atmospheric tower (16); the bottom oil of a flash tower (14) is sent into an atmospheric furnace (15) through a flash pump to be heated to 365-390 ℃, and then enters a flash section of the atmospheric tower (16) for oil-gas separation, the liquid phase passes through a deep-drawing stripping tower plate (30) added at the bottom of the atmospheric tower (16) and is subjected to enhanced stripping by less than 1% of superheated steam, the content of the fraction of atmospheric residue below 365 ℃ is reduced to be less than 2% so as to reduce the load of a vacuum furnace (21), a vacuum oil transfer line (22) and a vacuum tower (23), the vapor phase is defoamed, then passes through a desuperheating rectification section (17) arranged at the upper part of the flash section to exchange heat with part of the circulating reflux thermogravimetric diesel oil and carry out rectification separation, the initial distillation point of the heavy diesel oil is controlled to be more than 360 ℃, and forms a desuperheating degree of more than 5 ℃ with 98% of the fraction of second-line diesel oil (20), and the vapor phase is; the atmospheric residue is directly heated to 390-420 ℃ by a vacuum furnace (21) and then enters a vacuum tower (23) for flash evaporation section oil-gas separation, the liquid phase is reduced to be less than 5 percent of the fraction content before the cut point in the vacuum residue by using 0.01-0.2 percent superheated steam for micro-wet distillation through a deep-drawing stripping tower plate (30) added at the bottom of the vacuum tower (23), the vacuum residue (24) is pumped out by an atmospheric leg of the vacuum tower (23) and is sent out with the victory oil after primary and secondary heat exchange, the vapor phase is defoamed and is then subjected to three-section condensation and rectification separation by the vacuum tower (23), and three-line-reduced wax oil (25), two-line-reduced wax oil (26) and one-line-reduced wax oil (27) are obtained and are sent out as products after being respectively heat exchanged with; and cooling the gas at the top of the decompression tower (23) by a cooler to obtain decompression condensate oil (28) and decompression dry gas, and pumping out the decompression dry gas by a decompression vacuum pump (29).

Wherein, the deep-drawing stripping column plate (30) is a fixed guide bar valve column plate, the aperture ratio of the plate surface is 0.5-3%, and the aperture point is increased by more than 50% compared with the common rectification column plate; the two ends of the fixed strip valve are fixed with the plate surface, and the side surface is provided with holes, and the height of the strip seam is only 0.5-2 mm; flash evaporation sections of the primary distillation tower (8), the atmospheric tower (16), the flash evaporation tower (14) and the vacuum tower (23) are all provided with foam removers, and stripping sections are all provided with deep-drawing stripping tower plates (30).

Compared with the ordinary vacuum distillation of Shengli crude oil, the content of distillate is reduced by 10-15 percent before the bottom oil of the primary tower (8) is lower than the primary feeding temperature, and the temperature is increased by 15-25 ℃ after the second-stage exchange; the flash tower (14) is additionally arranged in front of the atmospheric furnace (15), so that the feeding amount of the atmospheric furnace (15) is reduced by more than 20%, although the outlet temperature of the atmospheric furnace (15) is increased by 15-25 ℃, the heat exchange efficiency of the atmospheric furnace tube (15) is improved by more than 10%, and the energy of the atmospheric furnace (15) is saved by more than 20%. The content of the front cut fraction at 360 ℃ in the atmospheric residue oil is reduced by more than 7 percent, the content of the front cut fraction at 360 ℃ in the heavy diesel oil is reduced by more than 40 percent, the yield of high-quality straight-run diesel oil is improved by more than 6 percent, the vaporization load of a vacuum furnace (21) is reduced by 17 percent, the temperature drop of a vacuum oil transfer line (22) is reduced by 5-7 ℃, and the pressure drop is reduced by more than 15 percent, so that the energy of the vacuum furnace (21) is saved by more than 15 percent, and the feeding temperature of a vacuum tower (23) is improved by more than 5. In addition, the load and the pressure drop of the vacuum tower (23) are reduced by more than 10 percent, the content of the fraction before the cutting point in the vacuum residue oil is reduced by more than 10 percent, the yield of the vacuum deep-drawing wax oil is improved by more than 6 percent, the cutting point can reach 620 ℃, and the economic benefits of product increment and process energy saving are very obvious.

The atmospheric and vacuum high-efficiency energy-saving deep drawing process based on clear cutting provided by the invention is integrally considered from an atmospheric and vacuum device, and the integral effect of vacuum deep drawing and energy-saving efficiency improvement is formed only by integrating and using various measures in each process, and the deficiency of any measure can influence the optimal effect of vacuum deep drawing and energy-saving efficiency improvement. The deep-drawing stripping tower plate is additionally arranged on the primary distillation tower, so that the cutting definition of oil cutting at the bottom of the primary distillation tower is improved, the two-section heat exchange effect is enhanced, the pressure drop of the two-section heat exchanger is reduced, the temperature after the two-section heat exchange is improved, the load of the atmospheric furnace is reduced, and the energy conservation of the atmospheric furnace is facilitated; by additionally arranging the flash tower and the deep-drawing stripping tower plate of the flash tower, a large amount of light components are separated and enter the atmospheric tower in advance, and the cutting definition of bottom oil of the flash tower is improved, so that the pressure drop and the heat load of an atmospheric furnace are reduced, the feeding temperature and the gasification rate of the atmospheric tower are improved, and the heating energy consumption is reduced; the deep-drawing stripping tower plate is additionally arranged on the atmospheric tower, so that the cutting definition of atmospheric residue oil is improved, the yield and the economic benefit of high-quality light diesel oil are improved, the loads and the pressure drops of a vacuum furnace, a reduced-pressure oil transfer line and the vacuum tower are reduced, the temperature drop of the reduced-pressure oil transfer line is reduced, the feeding temperature and the flash evaporation vacuum degree of the vacuum tower are improved, and the reduced-pressure deep-drawing degree is improved and the energy consumption of the vacuum furnace is reduced; the deep-drawing stripping tower plate is additionally arranged at the bottom of the vacuum tower, so that the cutting definition of the vacuum residue oil is improved, the high-quality wax oil in the residue oil is greatly reduced, and the yield of the vacuum tower wax oil at the same vacuum cutting temperature is greatly improved; the feeding temperature of the atmospheric tower is increased, and a desuperheating rectifying section is additionally arranged, so that the light diesel oil component in the heavy diesel oil is greatly reduced, the atmospheric residue oil does not contain the light diesel oil component, the yield of high-quality diesel oil is greatly increased, the loads and the pressure drop of a vacuum furnace, a vacuum oil transfer line and a vacuum tower are greatly reduced, the feeding temperature and the flash evaporation vacuum degree of the vacuum tower are increased, and the vacuum deep-drawing degree is freely regulated and controlled. The comprehensive use of the technical measures ensures that the energy consumption of the atmospheric and vacuum distillation deep drawing is reduced, and more qualified raw materials are provided for downstream catalytic cracking, hydrocracking and coking units, thereby improving the economic benefit of the whole refinery.

Claims (3)

1. An atmospheric and vacuum energy-saving deep drawing process based on clear cutting is characterized in that crude oil is subjected to first-stage heat exchange with first-line diesel oil, first-line wax oil reduction, second-line diesel oil, second-line wax oil reduction, first-stage after-replacement heavy diesel oil, first-stage after-replacement third-line wax oil and first-stage after-replacement vacuum residue oil in sequence; the crude oil enters a flash evaporation section of a primary distillation tower after heat exchange at 180-240 ℃, the vapor phase is defoamed and then enters a rectification section of the primary distillation tower to be separated to obtain straight-run gasoline and light diesel oil, the liquid phase is subjected to enhanced stripping by less than 1% of superheated steam through a deep-drawing stripping tower plate added at the bottom of the primary distillation tower, and the content of distillate in the tower bottom oil before the temperature is lower than the feeding temperature of the primary distillation tower is reduced to be less than 1% -3%; the bottom oil of the primary distillation tower sequentially carries out second-stage heat exchange with heavy diesel oil, third-line wax reducing oil and vacuum residue oil; after the second-stage heat exchange, the bottom oil of the primary tower is subjected to oil-gas separation by adding a flash tower in front of the atmospheric tower at 300-360 ℃, the content of distillate in the liquid phase oil is reduced to 1-5% to reduce the load of the atmospheric tower before the temperature is lower than the second-stage heat exchange, and the flash steam is defoamed and then is directly introduced into a heavy diesel stripping return tower opening of the atmospheric tower; the flash oil is sent into an atmospheric furnace through a flash pump to be heated to 365-390 ℃ and then enters a flash section of the atmospheric tower for oil-gas separation, the liquid phase is subjected to enhanced steam stripping by using less than 1% of superheated steam through a deep-drawing stripping tower plate added at the bottom of the atmospheric tower, the content of fractions before the atmospheric residue is lower than 365 ℃ in the atmospheric residue is reduced to be less than 2% so as to reduce the load of a vacuum furnace, a vacuum oil transfer line and a vacuum tower, the vapor phase is subjected to heat exchange and rectification separation with partial cycle reflux thermogravimetric diesel oil through a desuperheating rectification section arranged at the upper part of the flash section after defoaming, the initial distillation point of the heavy diesel oil is controlled to be more than 360 ℃, the heavy diesel oil and 98% distillation temperature of second-line diesel oil fraction form a vacuum degree of more than 5 ℃, and; the normal pressure residual oil is directly heated to 390-420 ℃ by a vacuum furnace and then enters a flash evaporation section of the vacuum tower for oil-gas separation, the liquid phase is subjected to micro wet distillation by using 0.01-0.2% superheated steam through a deep-drawing stripping tower plate added at the bottom of the vacuum tower to reduce the content of fractions before the cut point in the vacuum residual oil to less than 5%, the vacuum residual oil is pumped out by an atmospheric leg of the vacuum tower and is sent out after primary and secondary heat exchange with raw oil, the vapor phase is defoamed and is subjected to three-section condensation and rectification separation by the vacuum tower to obtain three-line reduced wax oil, two-line reduced wax oil and one-line reduced wax oil, and the three-line reduced wax oil and; and cooling the gas at the top of the pressure reduction tower by a cooler to obtain pressure reduction condensate oil and pressure reduction dry gas, and pumping the pressure reduction dry gas out by a pressure reduction vacuum pump.

2. The atmospheric and vacuum energy-saving deep drawing process based on clear cutting as claimed in claim 1, wherein the deep drawing stripping tower plate is a fixed guide strip valve tower plate, the aperture ratio of the plate surface is 0.5% -3%, and the aperture point is increased by more than 50% compared with that of a common rectification tower plate; the two ends of the fixed strip valve are fixed with the plate surface, and the side surface is provided with holes, and the height of the strip seam is only 0.5-2 mm.

3. The energy-saving atmospheric and vacuum deep drawing process based on clear cutting as claimed in claim 1, wherein the flash evaporation sections of the primary tower, the atmospheric tower, the flash evaporation tower and the vacuum tower are all provided with demister, and the stripping section is all provided with deep-drawing stripping tower plate.

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