阅读说明：本技术 一种常减压装置减压蜡油馏分的优化加工工艺流程 (Optimized processing technological process of pressure-reducing wax oil fraction of atmospheric and vacuum distillation unit ) 是由 王明东 贺黎明 侯玉宝 王萌 李中新 赵娟 李玉飞 周志航 *** 于 2019-12-13 设计创作，主要内容包括：本发明公开了一种常减压装置减压蜡油馏分的优化加工工艺流程,通过改造减一线,将原本通入蜡油加氢反应器的减一线改为跨过蜡油加氢反应器,连接到分馏加热炉进口管线,避免减一线物流中的柴油耗氢,随后通往分馏加热炉,经过分馏加热炉预热,蜡油、柴油的混合物再进入分馏塔,通过提高分馏塔中段柴油返塔温度,提升柴油、蜡油的分离精度。在分馏塔的中段抽出柴油,而分馏塔塔底的蜡油则被抽出,送往催化裂化装置。整体看来,本发明公开的技术方案实现起来简单容易,改造成本低,另外能够降低氢耗,也有利于节约能源。(The invention discloses an optimized processing process flow of a pressure-reducing wax oil fraction of an atmospheric and vacuum distillation device, which is characterized in that a reduced line is reformed, the reduced line which is originally introduced into a wax oil hydrogenation reactor is changed to cross over the wax oil hydrogenation reactor and is connected to an inlet pipeline of a fractionating heating furnace, so that hydrogen consumption of diesel oil in the reduced line material flow is avoided, the reduced line material flow is introduced into the fractionating heating furnace, the mixture of the wax oil and the diesel oil enters a fractionating tower after being preheated by the fractionating heating furnace, and the separation precision of the diesel oil and the wax oil is improved by improving the temperature of the diesel oil at the middle. The diesel oil is extracted from the middle section of the fractionating tower, and the wax oil at the bottom of the fractionating tower is extracted and sent to the catalytic cracking device. In the whole view, the technical scheme disclosed by the invention is simple and easy to realize, the transformation cost is low, in addition, the hydrogen consumption can be reduced, and the energy source saving is also facilitated.)

1. An optimized processing process flow of pressure-reduced wax oil fractions of an atmospheric and vacuum distillation device is characterized in that oil firstly enters an atmospheric tower and then enters a vacuum tower (1), the oil produced by the vacuum tower (1) is provided with a first reduction line (5), a second reduction line (6) and a third reduction line (7), the second reduction line (6) and the third reduction line (7) of the vacuum tower (1) lead to a wax oil hydrogenation reactor (2), then the oil in the wax oil hydrogenation reactor (2) is introduced into a fractionation heating furnace (3) through a fractionation heating furnace inlet pipeline (8), material flow heated by the fractionation heating furnace (3) is introduced into a fractionation tower (4) through a fractionation tower inlet pipeline (9), a diesel oil production line (10) is arranged at the middle section of the fractionation tower (4), the diesel oil production line (10) is divided into two paths, one path leads to a diesel oil stripping tower, the other path returns to the fractionation tower (4), a wax oil production line (11) is, the extracted wax oil is sent to a catalytic cracking device, and the method is characterized in that: a reduction line (5) crosses over the wax oil hydrogenation reactor (2), is connected to the fractionation furnace inlet line (8), and then leads to the fractionation furnace (3).

2. The optimized processing process flow of the vacuum wax oil fraction of the atmospheric and vacuum distillation unit as claimed in claim 1, wherein: the pressure at the top of the fractionating tower (4) is maintained at 0.04MPa, the temperature at the top of the fractionating tower is maintained at 105-110 ℃ and the temperature at the bottom of the fractionating tower is maintained at 328-332 ℃.

3. The optimized processing process flow of the vacuum wax oil fraction of the atmospheric and vacuum distillation unit as claimed in claim 2, wherein: the fractionating tower (4) has 36 layers of floating valve trays, and the material is fed at the 33 rd layer of floating valve trays; the diesel oil extraction line (10) is extracted from the 17 th layer of floating valve tray of the fractionating tower (4), then part of heat is removed, and the diesel oil extraction line (10) is divided into two paths, wherein one path returns to the 16 th layer of floating valve tray of the fractionating tower (4).

4. The optimized process flow of the atmospheric and vacuum distillation unit as claimed in claim 1, wherein: controlling the temperature of the material flow in the middle section diesel oil extraction line (10) of the fractionating tower (4) to return to the fractionating tower (4) at 175-180 ℃.

Technical Field

The invention belongs to the technical field of petroleum processing, and particularly relates to an optimized processing process flow of vacuum wax oil fractions of an atmospheric and vacuum distillation unit.

Background

In the normal pressure reduction device, a normal pressure device distills light components with low boiling point, cuts components such as straight-run gasoline, kerosene, light diesel oil, heavy diesel oil and the like, and obtains products after simple refining, the pressure reduction device further separates the rest components such as reduced pressure wax oil, reduced pressure residue oil and the like, and the products such as gasoline, diesel oil and the like are produced through further cutting separation by processes such as fractionation and the like. Ideally, the diesel oil fraction can be directly extracted from a normal pressure device and can be prepared into a product through simple refining, however, the vacuum wax oil in the conventional pressure reduction device contains diesel oil components, the diesel oil fraction is used as a secondary processing raw material and is partially changed into lighter gasoline, liquefied gas and the like after being cracked by a high-pressure wax oil hydrogenation device, and the vacuum wax oil also can generate partial diesel oil components after passing through a hydrogenation reactor. This reduces the diesel-steam ratio of primary processing, increases the load of secondary processing, increases hydrogen consumption, and increases the oil refining cost.

The method for reducing the overlapping of the straight-run diesel oil and the vacuum wax oil in the atmospheric and vacuum distillation device mainly comprises the following measures: (1) the method comprises the steps of (1) improving the outlet temperature of an atmospheric furnace and increasing the steam stripping amount at the bottom of an atmospheric tower, directly improving the diesel oil yield of an atmospheric device, (2) modifying the lower section of the atmospheric tower, improving the fractionation precision, improving the diesel oil yield of the atmospheric device, (3) reinjecting part of reduced pressure wax oil into an atmospheric system, performing re-fractionation on the reduced pressure diesel oil component, recovering the diesel oil component in part of reduced pressure wax oil, (4) adjusting the pressure reduction operation, improving the side separation precision, and directly producing finished diesel oil from the reduced line diesel oil fraction. At present, the commonly adopted scheme is a technical scheme that decompression operation is adjusted, the side line separation precision is improved, and finished diesel is directly output from a side line, but the problems caused by the scheme are also many. Firstly, because there are many devices at present when designing, can contain the diesel oil component in the vacuum tower not considering, but in recent years because of crude oil change, can contain the diesel oil component in the vacuum tower of many devices, like this, if want to make the direct output finished product diesel oil of subtracting a line, just need to carry out bigger transformation to former device, especially tower equipment, the process conditions and the control parameter of vacuum tower can take place great change, and correspondingly, the operating mode of whole low reaches device also can take place the change on a large scale, just so greatly increased the transformation cost, also promoted the operation degree of difficulty, in addition, also can make the heat load of vacuum tower grow.

Disclosure of Invention

In order to solve the problems in the background art, under the condition of ensuring that diesel oil in wax oil can be fully separated, the purposes of reducing the transformation difficulty of the whole process 1, reducing the complexity and operation difficulty of the whole process 2, reducing the heat load of a vacuum tower 3 and reducing the hydrogen consumption of a wax oil hydrogenation device 4 are achieved, and the invention provides an optimized processing process flow of vacuum wax oil fractions of an atmospheric and vacuum device.

The utility model provides an atmospheric and vacuum distillation plant's optimization process flow an atmospheric and vacuum distillation plant decompression wax oil fraction optimizes processing process flow, the oil is advanced to be gone into the atmospheric tower, get into the vacuum tower subsequently, the extraction of vacuum tower has subtract first line, subtract second line and subtract third line, the subtract second line of vacuum tower, it leads to wax oil hydrogenation ware to subtract the third line, oil in the wax oil hydrogenation ware passes through fractionating heating furnace inlet pipeline and lets in the fractionating heating furnace afterwards, the commodity circulation after the heating of fractionating heating furnace passes through fractionating tower inlet pipeline and lets in the fractionating tower, the middle section at the fractionating tower sets up a diesel oil extraction line, the diesel oil extraction line is divided into two routes, lead to the diesel oil stripper all the way, another route returns the fractionating tower, the fractionating tower bottom is equipped with a wax oil extraction line, it sends to catalytic cracking unit to extract wax oil: the reduced line crosses over the wax oil hydrogenation reactor, connects to the fractionation furnace inlet line, and then leads to the fractionation furnace.

Further, the pressure at the top of the fractionating tower was maintained at 0.04MPa, the temperature at the top of the fractionating tower was maintained at 105-110 ℃ and the temperature at the bottom of the fractionating tower was maintained at 328-332 ℃.

Further, the fractionating tower has 36 layers of floating valve trays, and the material is fed at the 33 rd layer of floating valve trays; the diesel oil extraction line is extracted from the 17 th layer of floating valve tray of the fractionating tower, part of heat is removed, and the diesel oil extraction line is divided into two paths, wherein one path returns to the 16 th layer of floating valve tray of the fractionating tower.

Further, the temperature of the material flow in the diesel oil extraction line at the middle section of the fractionating tower returning to the fractionating tower is controlled at 175-180 ℃.

In the prior art, the fractionating tower can separate the diesel oil from the wax oil, and only the content of the diesel oil in the prior art is relatively low, so that when the content of the diesel oil is increased, the temperature of material flow in a middle-section diesel oil extraction line of the fractionating tower returned to the fractionating tower is increased, and the separation precision of the wax oil and the diesel oil can be further improved.

Compared with the prior art, the invention has the beneficial effects that:

1. because only a line is reduced to cross the part of wax oil hydrogenation reaction and is connected to an inlet pipeline of a fractionation heating furnace, the modification difficulty and modification cost of the whole process are greatly reduced;

2. because the process change does not involve the pressure reducing tower, the control parameters of the pressure reducing tower cannot be changed, the complexity and the operation difficulty of the whole optimization process are reduced, the heat load of the pressure reducing tower is further reduced, and the energy is saved;

3. unnecessary diesel oil hydrogenation is avoided, so that the hydrogen consumption of the wax oil hydrogenation device is reduced, the cost is saved, and the energy is saved.

Drawings

FIG. 1: an optimized processing process flow of a vacuum wax oil fraction of an atmospheric and vacuum distillation device;

in the figure: 1. the system comprises a vacuum tower, 2 wax oil hydrogenation reactors, 3 fractionation heating furnaces, 4 fractionation towers, 5 first-line reduction, 6 second-line reduction, 7 third-line reduction, 8 fractionation heating furnace inlet pipelines, 9 fractionation tower inlet pipelines, 10 diesel oil extraction lines and 11 wax oil extraction lines.

Detailed Description

The present invention is explained, but not limited to, and the technical solutions obtained in the light of the idea of the present invention should be included in the scope of protection of the present patent.