CN108441251B

CN108441251B - Cryogenic distillation process

Info

Publication number: CN108441251B
Application number: CN201810262159.9A
Authority: CN
Inventors: 马银泉
Original assignee: Shangqiu Zhongqing Environmental Protection Technology Co ltd
Current assignee: Shangqiu Zhongqing Environmental Protection Technology Co ltd
Priority date: 2018-03-28
Filing date: 2018-03-28
Publication date: 2021-02-23
Anticipated expiration: 2038-03-28
Also published as: CN108441251A

Abstract

The invention discloses a low-temperature distillation process, which comprises a first distillation assembly, a second distillation assembly and a third distillation assembly, wherein each distillation assembly is respectively provided with a distillation still, a distillation tower, a condenser and an oil storage tank, and oil products such as gasoline, light diesel oil, heavy oil and the like can be sequentially separated by controlling the temperature gradient rise of the distillation still in each distillation assembly.

Description

Cryogenic distillation process

Technical Field

The invention belongs to the technical field of oil refining equipment, and particularly relates to a low-temperature distillation process.

Background

Compared with foreign crude oil components, the crude oil components in China have higher content of vacuum residue, and the quality of the vacuum residue in the crude oil of most oil fields reaches 40-50 percent. Especially old oil fields, not only the yield is reduced, but also the heavy oil tendency of crude oil is increased. In addition, the degree of external dependence of crude oil in China is high, reaching 75 percent, and the weight ratio is increasingly excited. Therefore, the development of the enhanced distillation technology of crude oil, especially heavy crude oil, to improve the deep processing of heavy oil or heavy crude oil, fully utilize limited petroleum resources, increase the yield of light oil, and improve economic benefits has become an urgent problem to be solved in the petroleum refining industry in China, and is also an important direction for the progress and development of the modern distillation technology of crude oil or heavy crude oil.

Disclosure of Invention

The purpose of the invention is: the low-temperature distillation process can effectively improve the yield of light oil and increase the economic benefit of enterprises.

The technical scheme of the invention is as follows: a low-temperature distillation process is characterized by comprising a first distillation assembly, a second distillation assembly and a third distillation assembly, wherein the first distillation assembly comprises a first distillation kettle, a first distillation tower and a first condenser, an inlet of the first distillation kettle is connected with an oil inlet pipeline, an oil gas outlet of the first distillation kettle is connected with the first distillation tower through a pipeline, an oil gas outlet at the upper part of the first distillation tower is connected with the first condenser through a pipeline, and an outlet of the first condenser is connected with a first storage tank; the second distillation assembly comprises a second distillation kettle, a second distillation tower and a second cooler, wherein an inlet of the second distillation kettle is connected with a bottom oil outlet at the bottom of the first distillation tower through a first oil pump pipeline, an outlet of the second distillation kettle is connected with the second distillation tower through a pipeline, an oil gas outlet at the upper part of the second distillation tower is connected with the second cooler through a pipeline, and an outlet of the second cooler is connected with a second storage tank; the third distillation assembly comprises a third distillation kettle, a third distillation tower and a third cooler, an inlet of the third distillation kettle is connected with a bottom oil outlet at the bottom of the second distillation tower through a second oil pump pipeline, an outlet of the third distillation kettle is connected with the third distillation tower, an oil gas outlet at the upper part of the third distillation tower is connected with the third cooler through a pipeline, and an outlet of the third cooler is connected with a third storage tank; the temperature of the first distillation kettle is 110-; the unseparated oil product falling at the bottom of the first distillation tower is pumped into a second distillation assembly through a first oil pump pipeline, the temperature of the second distillation tower in the second distillation assembly is controlled at 260 ℃ for 250-.

The first distillation still is provided with a main heating device, and the second distillation still and the third distillation still are connected with the first distillation still through hot air pipelines.

The top of the first distillation kettle is also connected with a tail gas purification device through a tail gas pipeline.

The second distillation still and the third distillation still are respectively connected with a combustion furnace of the first distillation still through non-condensable gas pipelines.

And residual oil outlets are respectively arranged at the bottoms of the first, second and third distillation kettles and are respectively connected with a residual oil treatment device through pumping pipelines.

The low-temperature distillation process adopts the third distillation, can effectively decompose the crude oil into light gasoline, light diesel oil and heavy oil products according to different temperature control, has simple integral structure, convenient operation and use and low energy consumption in the working process, can carry out long-time continuous production, and has the characteristics of energy conservation, environmental protection and high decomposition efficiency.

Drawings

FIG. 1 is a schematic diagram of the cryogenic distillation process of the present invention.

Detailed Description

The low-temperature distillation process adopts three-stage distillation operation, and the specific structure is shown in figure 1, and the low-temperature distillation process mainly comprises a first distillation assembly, a second distillation assembly and a third distillation assembly, wherein the first distillation assembly comprises a first distillation kettle 1, a first distillation tower 2 and a first condenser 3, an inlet of the first distillation kettle 1 is connected with an oil inlet pipeline 5, an oil gas outlet of the first distillation kettle 1 is connected with the first distillation tower 2 through a pipeline, an oil gas outlet at the upper part of the first distillation tower 2 is connected with the first condenser 3 through a pipeline, and an outlet of the first condenser 3 is connected with a first storage tank 4; the second distillation component comprises a second distillation kettle 7, a second distillation tower 8 and a second cooler 9, wherein the inlet of the second distillation kettle 7 is connected with the bottom oil outlet at the bottom of the first distillation tower 2 through a first oil pump pipeline 6, the outlet of the second distillation kettle 7 is connected with the second distillation tower 8 through a pipeline, the oil gas outlet at the upper part of the second distillation tower 8 is connected with the second cooler 9 through a pipeline, and the outlet of the second cooler 9 is connected with a second storage tank 10; the third distillation assembly comprises a third distillation still 12, a third distillation tower 13 and a third cooler 15, an inlet of the third distillation still 12 is connected with a bottom oil outlet at the bottom of the second distillation tower 8 through a second oil pump pipeline 11, an outlet of the third distillation tower 12 is connected with the third distillation tower 13, an oil gas outlet at the upper part of the third distillation tower 13 is connected with the third cooler 15 through a pipeline, and an outlet of the third cooler 15 is connected with a third storage tank 16.

In the low-temperature distillation process, a first distillation kettle 1 is a main heating furnace, a combustion furnace device is arranged on the first distillation kettle 1, and a second distillation kettle 7 and a third distillation kettle 12 are respectively connected with the combustion furnace device of the first distillation kettle 1 through a hot air pipeline 20 so as to realize the heating distillation of oil products. The three distillation kettles are supplied with heat through the combustion furnace, so that the integral structure of the equipment can be simplified, and the maintenance, use and management costs of the equipment are reduced.

Further, a tail gas purification device 18 is connected to the top of the first still 1 through a tail gas pipe 17. Tail gas generated by combustion of the main heating device in the first distillation kettle 1 is sent into a tail gas purification device 18 through a tail gas pipeline 17, and after impurities in the tail gas are removed through a spray tower, standard emission is achieved, so that pollution of equipment production to the surrounding environment can be effectively reduced.

Furthermore, the second distillation still 7 and the third distillation still 12 are connected with the combustion furnace device on the first distillation still 1 through the non-condensable gas pipeline respectively, so that fuel is continuously provided for the combustion furnace, the combustion furnace is started for the first time, and the non-condensable gas produced in the production process can be used for the fuel of subsequent combustion, so that the overall energy consumption of the equipment can be effectively reduced, and energy conservation and environmental protection are realized.

In the low-temperature distillation process, residual oil outlets are respectively arranged at the bottoms of the first distillation still 1, the second distillation still 7 and the third distillation still 12, and the residual oil outlets are respectively connected with a residual oil treatment device 19 through pumping pipelines 14. The residual oil treatment device 19 can further separate residual oil, and the oil product separation efficiency of the whole equipment is improved.

During specific production, a combustion furnace device arranged on a first distillation kettle 1 heats a second distillation kettle 7 and a third distillation kettle 12 through a hot air pipeline 20 while heating the first distillation kettle 1, the temperature of the first distillation kettle 1 is controlled at 110-; the oil product which can not be condensed at the temperature falls into the bottom of the first distillation tower 2, and is pumped into the second distillation kettle 7 through the first oil pump pipeline, the temperature of the second distillation kettle 7 is controlled at 250-260 ℃, at the temperature, the light diesel oil contained in the oil product is separated in the second distillation tower 8 and then enters the second condenser 9, the condensed oil flows into the second storage tank 10, the residual oil falls into the bottom of the second distillation tower 8 and is pumped into the last third distillation kettle 12 through the second oil pump pipeline, the temperature of the third distillation kettle 12 is controlled at 370-390 ℃, the heavy diesel oil is separated out through the third distillation kettle 12 and the third distillation tower 13 at the temperature and is sent into the third storage tank 15, the residual oil which can not be distilled in the first distillation kettle 1, the second distillation kettle 7 and the third distillation kettle 12 is left at the bottom of the furnace, the residual oil is sent into the residual oil treatment device 19 through the pumping pipeline 14 after continuous production for a period of time, further separating out bitumen and other heavy oils.

Claims

1. A low-temperature distillation process is characterized by comprising a first distillation assembly, a second distillation assembly and a third distillation assembly, wherein the first distillation assembly comprises a first distillation kettle, a first distillation tower and a first condenser, an inlet of the first distillation kettle is connected with an oil inlet pipeline, an oil gas outlet of the first distillation kettle is connected with the first distillation tower through a pipeline, an oil gas outlet at the upper part of the first distillation tower is connected with the first condenser through a pipeline, and an outlet of the first condenser is connected with a first storage tank; the second distillation assembly comprises a second distillation kettle, a second distillation tower and a second cooler, wherein an inlet of the second distillation kettle is connected with a bottom oil outlet at the bottom of the first distillation tower through a first oil pump pipeline, an outlet of the second distillation kettle is connected with the second distillation tower through a pipeline, an oil gas outlet at the upper part of the second distillation tower is connected with the second cooler through a pipeline, and an outlet of the second cooler is connected with a second storage tank; the third distillation assembly comprises a third distillation kettle, a third distillation tower and a third cooler, an inlet of the third distillation kettle is connected with a bottom oil outlet at the bottom of the second distillation tower through a second oil pump pipeline, an outlet of the third distillation kettle is connected with the third distillation tower, an oil gas outlet at the upper part of the third distillation tower is connected with the third cooler through a pipeline, and an outlet of the third cooler is connected with a third storage tank; the temperature of the first distillation kettle is 110-; the unseparated oil product falling at the bottom of the first distillation tower is pumped into a second distillation assembly through a first oil pump pipeline, the temperature of the second distillation tower in the second distillation assembly is controlled at 260 ℃ for 250-.

2. A cryogenic distillation process according to claim 1, wherein a combustion furnace is arranged outside the first distillation still, and the second distillation still and the third distillation still are respectively connected with the combustion furnace of the first distillation still through hot air pipelines.

3. The cryogenic distillation process of claim 2, wherein the top of the first distillation still is further connected to a tail gas purification device through a tail gas pipeline.

4. The cryogenic distillation process of claim 2, wherein the second still and the third still are further connected to a burner of the first still through a non-condensable gas pipeline, respectively, to continuously supply fuel to the burner.

5. The cryogenic distillation process of claim 1, wherein a residue outlet is provided at the bottom of each of the first, second and third distillation still, and each residue outlet is connected to a residue treatment device through a pumping pipe.