阅读说明：本技术 一种用于清洗制备中间相沥青反应釜的清洗方法 (Cleaning method for cleaning reaction kettle for preparing mesophase pitch ) 是由 翟拥军 邓文广 何旺 徐立 于 2021-08-31 设计创作，主要内容包括：本发明公开了一种用于清洗制备中间相沥青反应釜的清洗方法,该方法包括：S1、将清洗液打入待清洗的反应釜中；S2、将反应釜内维持温度恒定；S3、冲入氮气将反应釜内维持压力恒定；S4、反应釜开启搅拌；S5、卸掉压力,清洗液排进回收装置；S6、重复步骤S1-S5,清洗3-5次,完成清洗反应釜过程。本发明具有快速完成中间相沥青制备过程清釜问题,缩短生产周期,提高生产效率,且清洗剂可以重复利用,降低清洗成本的优点。(The invention discloses a cleaning method for cleaning a reaction kettle for preparing mesophase pitch, which comprises the following steps: s1, pumping the cleaning solution into a reaction kettle to be cleaned; s2, maintaining the temperature in the reaction kettle to be constant; s3, filling nitrogen to maintain the pressure in the reaction kettle constant; s4, starting the reaction kettle to stir; s5, releasing pressure, and discharging the cleaning solution into a recovery device; s6, repeating the steps S1-S5, cleaning for 3-5 times, and finishing the process of cleaning the reaction kettle. The method has the advantages of quickly finishing the kettle cleaning problem in the preparation process of the mesophase pitch, shortening the production period, improving the production efficiency, recycling the cleaning agent and reducing the cleaning cost.)

1. A cleaning method for cleaning a reaction kettle for preparing mesophase pitch is characterized by comprising the following steps: a cleaning step:

s1, pumping the cleaning solution into a reaction kettle to be cleaned;

s2, maintaining the temperature in the reaction kettle to be constant;

s3, filling nitrogen to maintain the pressure in the reaction kettle constant;

s4, starting the reaction kettle to stir;

s5, releasing pressure, and discharging the cleaning solution into a recovery device;

s6, repeating the steps S1-S5, cleaning for 3-5 times, and finishing the process of cleaning the reaction kettle.

2. The cleaning method for cleaning the reaction kettle for preparing the mesophase pitch according to claim 1, which is characterized in that: in the cleaning step S1, the cleaning liquid is FCC catalytic slurry oil cut oil in the distillation range of 450-500 ℃.

3. The cleaning method for cleaning the reaction kettle for preparing the mesophase pitch according to claim 1, which is characterized in that: the amount of the cleaning liquid in the cleaning step S1 is 80-95% of the total capacity of the reaction kettle.

4. The cleaning method for cleaning the reaction kettle for preparing the mesophase pitch according to claim 1, which is characterized in that: the inside temperature of the reaction vessel is maintained at 300 ℃ to 350 ℃ in the washing step S2.

5. The cleaning method for cleaning the reaction kettle for preparing the mesophase pitch according to claim 1, which is characterized in that: in the cleaning step S3, the pressure in the reaction kettle is maintained at 0.1MPa-1 MPa.

6. The cleaning method for cleaning the reaction kettle for preparing the mesophase pitch according to claim 1, which is characterized in that: and the stirring time of the reaction kettle in the cleaning step S4 is 10min-30 min.

7. The cleaning method for cleaning the reaction kettle for preparing the mesophase pitch according to claim 1, which is characterized in that: the stirring manner of the reaction kettle in the cleaning step S4 can be clockwise, counterclockwise and clockwise and counterclockwise alternate stirring.

8. The cleaning method for cleaning the reaction kettle for preparing the mesophase pitch according to claim 1, which is characterized in that: the cleaning liquid in the cleaning step S5 is recovered by distillation under reduced pressure.

Technical Field

The invention relates to the technical field of synthetic asphalt, in particular to a cleaning method for cleaning a reaction kettle for preparing mesophase asphalt.

Background

The asphalt is a black brown complex mixture composed of hydrocarbons with different molecular weights and nonmetal derivatives thereof, is one of high-viscosity organic liquids, mostly exists in a liquid or semisolid petroleum form, has a black surface, and can be dissolved in carbon disulfide and carbon tetrachloride. Asphalt is a waterproof, moistureproof and anticorrosive organic cementing material. The asphalt can be mainly divided into coal tar asphalt, petroleum asphalt and natural asphalt: among them, coal tar pitch is a by-product of coking. Petroleum pitch is the residue of crude oil distillation. Natural bitumen is stored underground, and some forms a mineral layer or is accumulated on the surface of the crust. The asphalt is mainly used in the industries of paint, plastics, rubber and the like and pavement and the like.

The preparation of the mesophase pitch is mostly carried out in a reaction kettle, and belongs to batch reaction. After the mesophase pitch is discharged from the reaction kettle, a large amount of pitch remains on the inner wall of the reaction kettle. If the kettle is not cleaned and directly fed for next preparation, the residual materials on the kettle wall can be excessively polymerized in the next polymerization process to become asphalt coke, which seriously influences the quality of the mesophase asphalt, so that the kettle is required to be thoroughly cleaned every time the mesophase asphalt is produced. At present, the most common method is to polish the asphalt by a mechanical method after the reaction kettle is cooled, and strip the asphalt from the kettle wall. The method has low cleaning efficiency and more dead angles, generates a large amount of asphalt dust to influence the health of operators, and simultaneously polishes the kettle wall for a long time to greatly influence the service life of the kettle and generate potential safety hazards.

Disclosure of Invention

The invention aims to provide a cleaning method for cleaning a reaction kettle for preparing mesophase pitch, which aims to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a cleaning method for cleaning a reaction kettle for preparing mesophase pitch comprises the following cleaning steps:

s1, pumping the cleaning solution into a reaction kettle to be cleaned;

s2, maintaining the temperature in the reaction kettle to be constant;

s3, filling nitrogen to maintain the pressure in the reaction kettle constant;

s4, starting the reaction kettle to stir;

s5, releasing pressure, and discharging the cleaning solution into a recovery device;

s6, repeating the steps S1-S5, cleaning for 3-5 times, and finishing the process of cleaning the reaction kettle.

As a further scheme of the invention, in the cleaning step S1, the cleaning liquid is FCC catalytic slurry oil cutting oil with the distillation range of 450-500 ℃.

As a further scheme of the invention, the amount of the cleaning liquid in the cleaning step S1 is 80-95% of the total capacity of the reaction kettle.

As a further embodiment of the present invention, the temperature in the reaction vessel is maintained at 300 ℃ to 350 ℃ in the washing step S2.

In a further embodiment of the present invention, the pressure in the reaction vessel is maintained at 0.1MPa to 1MPa in the washing step S3.

As a further scheme of the invention, the stirring time of the reaction kettle in the cleaning step S4 is 10min-30 min.

As a further scheme of the invention, the stirring mode of the reaction kettle in the cleaning step S4 can be clockwise, counterclockwise and clockwise and counterclockwise alternate stirring.

In a further embodiment of the present invention, the cleaning liquid is recovered in the cleaning step S5 by distillation under reduced pressure.

Compared with the prior art, the invention has the beneficial effects that: need not wait for after the reation kettle cooling again to reation kettle carry out machinery and polish, after the pitch ejection of compact, the very first time washs reation kettle, has shortened the scavenging period greatly and has improved production efficiency.

The cleaning dead angle is not existed, and the cleaning is more thorough compared with the mechanical method.

The corrosion does not exist, the kettle body is not required to be polished, and the service life of the reaction kettle is not influenced.

The dust environment does not exist, so that the environment is more environment-friendly; the cleaning agent can be recycled, and the cleaning cost is lower.

Detailed Description

The technical solutions in the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "both ends", "one end", "the other end", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown herein, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, such as "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1

The embodiment provided by the invention comprises the following steps: a cleaning method for cleaning a reaction kettle for preparing mesophase pitch comprises the following cleaning steps:

s1, pumping 90 kg of cleaning materials into the reaction kettle after discharging by a pump (effective volume is 100L).

S2, adjusting the temperature of the reaction kettle, and setting the temperature of the reaction kettle at 330 ℃.

And S3, introducing nitrogen into the reaction kettle through a pressure reducing valve after the temperature is reached, and maintaining the pressure in the reaction kettle at 5 kg.

S4, stirring the reaction kettle clockwise for 20 min.

S5, releasing the pressure and discharging the cleaning solution into a receiving groove of the recovery device.

S6, pumping 90 kg of cleaning materials into the reaction kettle again, repeating the steps S2-S5, and finishing cleaning.

After the cleaning is finished, the reaction kettle produces the intermediate phase asphalt, and after a production period, the main indexes of the intermediate phase asphalt are as follows: softening point/deg.C is 300; ash/ppm was 45; the spinnability is excellent.

Comparative example 1: after the intermediate phase asphalt is prepared, the reaction kettle directly enters the next production period without being cleaned, and the obtained intermediate phase asphalt has the main indexes that: softening point/deg.C is 306; ash/ppm is 80; the spinnability is general.

Example 2

The embodiment provided by the invention comprises the following steps: a cleaning method for cleaning a reaction kettle for preparing mesophase pitch comprises the following cleaning steps:

s1, pumping 90 kg of cleaning materials into the reaction kettle after discharging by a pump (effective volume is 100L).

S2, adjusting the temperature of the reaction kettle, and setting the temperature of the reaction kettle at 320 ℃.

And S3, introducing nitrogen into the reaction kettle through a pressure reducing valve after the temperature is reached, and maintaining the pressure in the reaction kettle at 8 kg.

S4, stirring the reaction kettle clockwise for 10min, and stirring the reaction kettle anticlockwise for 10 min.

S5, releasing the pressure and discharging the cleaning solution into a receiving groove of the recovery device.

S6, pumping 90 kg of cleaning materials into the reaction kettle again, repeating the steps S2-S5, and finishing cleaning.

After the cleaning is finished, the reaction kettle produces the intermediate phase asphalt, and after a production period, the main indexes of the intermediate phase asphalt are as follows: softening point/deg.C is 300; ash/ppm is 39; the spinnability is excellent.

Comparative example 2: s1, pumping 90 kg of cleaning materials into the reaction kettle after discharging by a pump (effective volume is 100L).

S2, adjusting the temperature of the reaction kettle, and setting the temperature of the reaction kettle at 320 ℃.

And S3, stirring for 10min clockwise and 10min counterclockwise after the temperature of the reaction kettle is reached.

S4, releasing the pressure and discharging the cleaning solution into a receiving groove of the recovery device.

S5, pumping 90 kg of cleaning materials into the reaction kettle again, repeating the steps S2-S5, and finishing cleaning.

After the cleaning is finished, the reaction kettle produces the intermediate phase asphalt, and after a production period, the main indexes of the intermediate phase asphalt are as follows: softening point/deg.C is 306; ash/ppm was 66; the spinnability was good.

The main difference between comparative example 1 and examples 1 and 2 is that: the mesophase pitch is directly produced without any cleaning, and as can be seen from the quality of the obtained mesophase pitch, the spinnability of the obtained mesophase pitch is poor and the ash content is increased without cleaning the reaction kettle, which are not beneficial to the preparation of high-quality carbon materials from the mesophase pitch.

The main difference between comparative example 2 and example 2 is that: the cleaning process does not pass through the pressure maintaining stage, and the quality of the obtained mesophase pitch is also reduced, which shows that the cleaning effect of the reaction kettle is greatly influenced by omitting the pressure maintaining stage in the cleaning process.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.