阅读说明：本技术 催化裂化原料预处理方法、轻质油生产方法及系统 (Catalytic cracking raw material pretreatment method, light oil production method and system ) 是由 李治 刘丹禾 雷杰 李康 韩海波 陈曼桥 王文柯 樊麦跃 魏小波 于 2019-10-31 设计创作，主要内容包括：本发明涉及催化裂化技术领域,公开了催化裂化原料预处理方法、轻质油生产方法及系统。催化裂化原料预处理方法,包括,对催化裂化原料进行空化预处理。轻质油生产方法,包括按照上述的预处理方法进行空化预处理后,再进行催化裂化反应。轻质油生产系统,包括空化预处理装置以及催化裂化反应系统,空化预处理装置与催化裂化反应系统的提升管连通。上述方法及系统,操作简单,成本低,能提高轻质油收率。(The invention relates to the technical field of catalytic cracking, and discloses a catalytic cracking raw material pretreatment method, a light oil production method and a system. The pretreatment method of the catalytic cracking raw material comprises the step of carrying out cavitation pretreatment on the catalytic cracking raw material. The light oil producing process includes the cavitation pre-treatment and the catalytic cracking reaction. The light oil production system comprises a cavitation pretreatment device and a catalytic cracking reaction system, wherein the cavitation pretreatment device is communicated with a riser of the catalytic cracking reaction system. The method and the system have the advantages of simple operation and low cost, and can improve the yield of the light oil.)

1. A catalytic cracking raw material pretreatment method is characterized by comprising the following steps:

before the catalytic cracking reaction of the catalytic cracking raw material, cavitation pretreatment is carried out.

2. The catalytic cracking feedstock pretreatment method of claim 1, wherein the cavitation pretreatment device is a venturi-type, liquid whistle-type, orifice plate-type or jet pipe-type cavitation device.

3. The catalytic cracking feedstock pretreatment method of claim 1, wherein the reaction pressure of the cavitation pretreatment is 2 to 20 Mpa;

preferably, the reaction pressure is 4-12 MPa.

4. The pretreatment method of catalytic cracking raw material according to claim 1, wherein a hydrogen donor is blended into the catalytic cracking raw material before the cavitation pretreatment, wherein the hydrogen donor accounts for 0.5-10% of the mass of the catalytic cracking raw material;

preferably, the blending amount of the hydrogen donor accounts for 1-5% of the mass of the catalytic cracking raw material.

5. The process of claim 4, wherein the hydrogen donor is a catalytic naphtha.

6. The method of claim 1, wherein the catalytic cracking feedstock is at least one of distillate oil, atmospheric residue, and blended vacuum residue.

7. A light oil production method is characterized by comprising the step of carrying out cavitation pretreatment on a catalytic cracking raw material according to the catalytic cracking raw material pretreatment method of any one of claims 1 to 6;

and carrying out catalytic cracking reaction on the catalytic cracking raw material subjected to cavitation pretreatment.

8. A light oil production process as claimed in claim 7, characterized in that the catalytic cracking reaction is carried out in a single-pass cracking, partial-recycle or full-recycle operation.

9. The light oil production system is characterized by comprising a cavitation pretreatment device and a catalytic cracking reaction system, wherein the cavitation pretreatment device is communicated with a riser of the catalytic cracking reaction system.

10. The light oil production system of claim 9, wherein the cavitation pretreatment device is a venturi-type, liquid whistle-type, orifice plate-type, or jet pipe-type cavitation device.

Technical Field

The invention relates to the technical field of catalytic cracking, in particular to a catalytic cracking raw material pretreatment method, a light oil production method and a system.

Background

Along with the increasing shortage of crude oil at home and abroad and the acceleration of the heavy and inferior degree of the crude oil, the high yield of light oil products in the crude oil processing process becomes a long-term trend, and the technical development compliance of the catalytic cracking process as a main crude oil secondary processing process is more important. In order to improve the yield of light oil products in the catalytic cracking process to a greater extent, scholars at home and abroad carry out a great deal of research and provide a lot of improvement methods.

Chinese patent CN1224672C discloses a catalytic cracking process for improving atomization effect of catalytic raw material, alleviating metal pollution and increasing gasoline yield. The invention mainly utilizes an emulsification technology to mix a catalytic raw material with an emulsifier and a passivator to form a water-in-oil emulsified raw material, the water-in-oil emulsified raw material is fully contacted with a high-temperature catalyst after primary atomization to form secondary micro-explosion atomization, and an oil phase outside a liquid drop is instantaneously split into oil drops with smaller particle sizes, so that the diameter of the atomized liquid drop can be reduced to be below 5um from 60-120um, and the purposes of improving product distribution and increasing the yield of light oil products are achieved. Patent CN106701148A discloses a catalytic feedstock pretreatment method for increasing the yield of light oil and increasing the octane number of gasoline. The main method is to mix a cyclic oxygen-containing organic compound in the conventional catalytic raw material, such as: one or more of ketones, ethers, esters, alcohols and the like are used for improving the performance of the catalytic raw materials, so that the aim of improving the yield of the light oil can be fulfilled, and the content of aromatic hydrocarbon in the gasoline is effectively improved. U.S. Pat. No. 5,54, 652 discloses a method for short reaction catalytic cracking apparatus. The method mainly achieves the purpose of ultrashort reaction time-millisecond by greatly shortening the length of the reaction tube, further reduces the back-mixing contact reaction of oil gas and a catalyst in the reaction tube, effectively avoids the problem of secondary reaction of an intermediate product in the catalysis process to achieve the purpose of improving the yield of the light oil, but has the problem of higher content of olefin in gasoline due to insufficient reaction depth.

At present, the existing methods for improving the yield of light oil products by the catalytic cracking process are applied to industrial production, and have the disadvantages of great modification to the original device, high cost and troublesome operation.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The invention provides a pretreatment method of catalytic cracking raw materials, aiming at improving the yield of catalytic cracking reaction light oil on the premise of not changing the original catalytic cracking reaction device.

The invention provides a method for producing light oil, and aims to provide a simple method capable of improving the yield of the light oil.

The light oil production system provided by the invention is simple to operate and high in light oil yield.

The invention is realized by the following steps:

in a first aspect, embodiments provide a catalytic cracking feedstock pretreatment process comprising:

before the catalytic cracking reaction of the catalytic cracking raw material, cavitation pretreatment is carried out.

In alternative embodiments, the means for cavitation pretreatment comprises venturi-type, liquid whistle-type, orifice plate-type, or jet tube-type cavitation devices.

In an alternative embodiment, the conditions of the cavitation pretreatment are: the reaction pressure is 2-20 Mpa;

preferably, the reaction pressure is 4-12 MPa.

In an alternative embodiment, the catalytic naphtha is blended with the catalytic cracking feedstock prior to the cavitation pretreatment.

In an optional embodiment, the blending amount of the catalytic crude gasoline accounts for 0.5-10% of the mass of the catalytic cracking raw material;

preferably, the blending amount of the catalytic crude gasoline accounts for 1-5% of the mass of the catalytic cracking raw material.

In an alternative embodiment, the catalytic cracking feedstock is at least one of distillate oil, atmospheric resid, and blendstock vacuum resid.

In a second aspect, embodiments provide a light oil production process comprising subjecting a catalytic cracking feedstock to a cavitation pretreatment in accordance with the catalytic cracking feedstock pretreatment process of any of the preceding embodiments;

and carrying out catalytic cracking reaction on the catalytic cracking raw material subjected to cavitation pretreatment.

In alternative embodiments, the catalytic cracking reaction is conducted in a single pass cracking, partial recycle, or full recycle operation.

In a third aspect, an embodiment provides a light oil production system, which includes a cavitation pretreatment device and a catalytic cracking reaction system, wherein the cavitation pretreatment device is communicated with a riser of the catalytic cracking reaction system;

in alternative embodiments, the cavitation pretreatment device is a venturi-type, liquid whistle-type, orifice plate-type, or jet tube-type cavitation device.

The invention has the following beneficial effects:

the invention relates to a pretreatment method of catalytic cracking raw materials, which is designed as follows: because the cavitation pretreatment is carried out before the catalytic cracking reaction is carried out on the catalytic cracking raw material.

1) The process is simple, only a cavitation treatment device is added at the front section of the conventional catalytic cracking process, the existing catalytic cracking process is not required to be transformed in a large scale, and the method has the advantages of simple generation device, low energy consumption, low maintenance cost, easy realization of industrialization and the like.

2) The cavitation-shock wave in the cavitation process can miniaturize part of asphaltene and colloid in the catalytic raw material, reduce the association degree of colloid asphaltene, make a colloid system looser, reduce the coking performance and ensure that the light oil yield is high after the catalytic cracking raw material treated by the method is subjected to catalytic cracking.

3) In the process of cavitation, the invention leads part of long-chain macromolecules to be broken, opens the rings of aromatic hydrocarbon and cyclane, realizes the lightening of the catalytic raw material, greatly reduces the viscosity of the raw material, improves the atomization performance of the catalytic raw material, and further leads the yield of light oil of the cavitated raw material for catalytic cracking reaction to be improved.

According to the light oil production method designed by the invention, because the cavitation treatment is carried out before the catalytic cracking reaction, the light oil production method has high yield, low cost and convenient operation.

According to the light oil production system obtained through the design, the cavitation treatment system is arranged in front of the catalytic cracking reaction system, so that the yield of the light oil produced by the production system is high.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a first process flow diagram of a light oil production system provided by an embodiment of the present invention;

fig. 2 is a first process flow diagram of a light oil production system according to an embodiment of the present invention.

Icon: 1-cavitation pretreatment device; 2-a regenerator; 3-catalytic cracking reaction settler; 4-heating the furnace; 5-a fractionation column; 6-a condenser; 7-a three-phase separator; 8-a stripping column; 9-a heat exchanger; 10-rich gas discharge pipe; 11-a crude gasoline discharge pipe; 12-light diesel oil discharge pipe; 13-blending crude gasoline conveying pipe; 14-heavy diesel discharge pipe; 15-catalytic slurry oil discharge pipe; 16-a recycle oil pipeline; 17-raw material inlet pipe.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The method for pretreating a catalytic cracking feedstock, the method for producing light oil, and the system for producing light oil according to the present invention will be described in detail below.

The embodiment of the invention provides a pretreatment method of a catalytic cracking raw material, which comprises the following steps:

before the catalytic cracking reaction of the catalytic cracking raw material, cavitation pretreatment is carried out.

The cavitation technology mainly utilizes the fact that when a catalytic raw material passes through a region with a rapidly reduced pipe diameter in the flowing process, the internal pressure of fluid is reduced due to the increase of flow velocity, and the fluid is gasified when the pressure is reduced to be lower than the saturated vapor pressure of the ambient temperature of the fluid, bubbles can be generated and grown in the liquid, a large number of bubbles can be rapidly collapsed along with the increase of the pipe diameter of the downstream of the fluid and the pressure recovery, and extreme energy such as high temperature, high pressure, high jet flow, high shear force and the like can be generated in a very narrow space at the moment of collapse of the bubbles. On one hand, the huge microscopic energy can break chains of part of long-chain macromolecules and open rings of part of aromatic hydrocarbons and cyclanes, thereby realizing the lightening of catalytic raw materials and improving the catalytic performance of the catalytic cracking raw materials; on the other hand, the super molecular structure of colloid asphaltene in the catalytic raw material is destroyed, the association degree of macromolecular groups is reduced, and partial asphaltene is converted into colloid and smaller molecular structures, so that the colloid system of the catalytic raw material becomes looser, the coking performance of the catalytic raw material is reduced, and the yield of light oil of the catalytic cracking raw material during catalytic cracking reaction can be effectively improved due to the reduction of the coking performance.

Therefore, the catalytic cracking raw material pretreatment method provided by the invention can be used for carrying out cavitation pretreatment on the catalytic cracking raw material, and can improve the yield of the light oil subjected to the subsequent catalytic cracking reaction.

Specifically, the cavitation pretreatment device is a venturi tube type, liquid whistle type, orifice plate type or jet pipe type cavitation device.

Preferably, the reaction pressure of the cavitation pretreatment is 2 to 20 MPa. The cavitation pretreatment under the pressure condition has better effect, and further, the reaction pressure is 4-12MPa for ensuring better cavitation effect.

Preferably, a hydrogen donor is blended with the catalytic cracking feedstock prior to cavitation pretreatment. The hydrogen donor accounts for 0.5-10% of the mass of the catalytic cracking raw material.

And in the process of radical weight recombination, more small molecule radicals can be combined with heavy oil molecule radicals to generate more small molecule substances so as to achieve the aim of light weight.

Preferably, in order to further ensure that more small molecular substances are generated and the yield of subsequent light oil is further improved, the blending amount of the hydrogen donor accounts for 1-5% of the mass of the catalytic cracking raw material.

Further, the hydrogen donor is catalytic naphtha; the catalytic crude gasoline has low price and easily obtained raw materials.

Preferably, the catalytic cracking raw material is at least one of distillate oil, atmospheric residue and blending vacuum residue.

The catalytic cracking reaction of the raw materials after the cavitation pretreatment method provided by the invention has obvious effect.

The invention provides a production method of light oil, which comprises the following steps:

the catalytic cracking raw material is subjected to cavitation pretreatment according to the catalytic cracking raw material pretreatment method provided by the invention.

Then carrying out catalytic cracking reaction on the catalytic cracking raw material subjected to cavitation pretreatment.

The light oil production method has high yield because the cavitation pretreatment is carried out before the catalytic cracking reaction.

Preferably, the catalyst used for the catalytic cracking reaction is a catalyst with micro-reaction activity of 55-65. Specifically, it may be at least one of SY molecular sieve, REHY molecular sieve, SRY molecular sieve, ZRP molecular sieve and ZSM-5 molecular sieve. In the embodiment of the invention, the CC-20D catalytic cracking industrial equilibrium catalyst in the SRY molecular sieve is preferably selected, and the micro-reaction activity is 65.

Preferably, the catalytic cracking reaction is carried out in a single pass cracking, partial recycle or full recycle operation. The above catalytic cracking reaction operation can produce light oil.

The light oil production system provided by the invention comprises a cavitation pretreatment device and a catalytic cracking reaction system, wherein the cavitation pretreatment device is communicated with a lifting pipe of the catalytic cracking reaction system. The production system is additionally provided with a cavitation pretreatment device in front of the catalytic cracking reaction system, so that the production system has high yield of light oil.

Specifically, the cavitation pretreatment device is a venturi tube type, liquid whistle type, orifice plate type or jet pipe type cavitation device.

More specifically, as shown in fig. 1 and 2, fig. 1 and 2 are two specific configurations of a light oil production system provided by the present invention. The light oil production system comprises a cavitation pretreatment device 1, a regenerator 2, a catalytic cracking reaction settler 3, a heating furnace 4, a fractionating tower 5, a condenser 6, a three-phase separator 7 and a stripping tower 8. The regenerator 2 is connected with a catalytic cracking reaction settler 3, and the upper part of the catalytic cracking reaction settler 3 is communicated with the lower part of a fractionating tower 5.

The upper part of the fractionating tower 5 is communicated with a three-phase separator 7, a pipeline communicated with the three-phase separator 7 is provided with a condenser 6, and the three-phase separator 7 is connected with a rich gas discharge pipe 10 and a crude gasoline discharge pipe 11.

The middle part of the fractionating tower is communicated with a stripping tower 8, and the stripping tower 8 is connected with a light diesel oil discharge pipe 12 and a heavy diesel oil discharge pipe 14.

The bottom of the fractionating tower 5 is communicated with the catalytic cracking reaction settler 3 through a recycle oil pipeline 16 and is connected with a catalytic slurry oil discharge pipe 15, and the bottom is also connected with a return pipe which returns to the lower part of the fractionating tower 5. A heat exchanger 9 is arranged among the oil refining pipeline 16, the catalytic slurry oil discharge pipe 15 and the return pipe.

As shown in fig. 1, fig. 1 is a specific structure of a first light oil production system. The lower part of the catalytic cracking reaction settler 3 is communicated with a heating furnace 4, the heating furnace 4 is communicated with a cavitation pretreatment device 1, and the cavitation pretreatment device 1 is communicated with a raw material inlet pipe 17. The catalytic cracking raw material enters the system through a raw material inlet pipe 17, enters a heating furnace 4 for heating after being pretreated by a cavitation pretreatment device 1, and then enters the catalytic cracking reaction system through a lifting pipe (not shown) at the lower part of a catalytic cracking reaction settler 3. A blending crude gasoline delivery pipe 13 is connected between the crude gasoline discharge pipe 11 and the raw material inlet pipe 17 so as to blend catalytic crude gasoline produced by a light oil production system into raw materials when the production is convenient.

As shown in fig. 2, the light oil production system of fig. 2 is a process flow diagram of the light oil production system using the recycled oil slurry generated by the light oil production system as a raw material. The cavitation pretreatment device 1 is arranged on the recycle oil pipeline 16, so that the recycle oil slurry is subjected to cavitation pretreatment by the cavitation pretreatment device 1 before being recycled.

The features and properties of the present invention are described in further detail below with reference to examples.