A heavy benzol residual oil processing and crude benzol recovery system
By using superheated steam heating and an optimized recovery tower design in the heavy benzene residue oil recovery system, the problems of slow heating rate and low separation efficiency of heavy benzene residue oil have been solved, achieving efficient crude benzene recovery and stable system operation with energy-saving effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- YUNNAN DAWEI HENGYUAN CHEM CO LTD
- Filing Date
- 2025-08-01
- Publication Date
- 2026-05-29
AI Technical Summary
Existing technologies for recovering heavy benzene residue oil suffer from problems such as slow heating speed, low separation efficiency, low extraction rate, and unstable operation, leading to resource waste.
Superheated steam heating is used to replace liquid-liquid heat transfer. Through the design of the recovery tower and optimization of the steam system, including components such as steam superheater, gas distributor, jacket and agitator, rapid and uniform heating and separation of heavy benzene residue oil is achieved, eliminating the need for traditional wash oil heaters.
It improves the separation efficiency of heavy benzene residue oil and the extraction rate of crude benzene, reduces the crude benzene reflux ratio, has good system operation stability, and has significant energy-saving effect.
Smart Images
Figure CN224292542U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of heavy benzene residue oil recovery and crude benzene technology, specifically to a heavy benzene residue oil processing and crude benzene recovery system. Background Technology
[0002] Benzene hydrogenation involves first removing heavy components from crude benzene from coking plants, then adding hydrogen to the light components and reacting them under high temperature and pressure in a reactor with a specialized catalyst. This process converts unsaturated dienes and monoolefins into saturated hydrocarbons. Further extraction and distillation processes remove impurities such as sulfur, nitrogen, and oxygen, yielding high-purity benzene and toluene. In addition to high-purity benzene, this process also produces large quantities of trimethylolpropene (TMP) and heavy benzene residues as byproducts. Statistics show that with an annual processing capacity of 120,000 tons of benzene hydrogenation, approximately 6,000 tons of heavy benzene residue are generated annually. This heavy benzene residue contains 30-35% crude benzene and 30-35% naphthalene oil, with the remainder being 30-40% wash oil, all of which have recycling value. To date, there are few dedicated recovery units for heavy benzene residue oil. Typically, a wash oil heater is used to heat the heavy benzene residue oil, resulting in slow heating and separation efficiency, uneven heating, and generally poor recovery performance, low crude benzene extraction rate, and unstable operation, leading to resource waste. Therefore, developing a heavy benzene residue oil processing and crude benzene recovery system with good recovery performance, high extraction rate, and stable operation is objectively necessary. Utility Model Content
[0003] The purpose of this invention is to provide a system for processing and recovering crude benzene from heavy benzene residue oil that has good recovery effect, high extraction rate, and stable operation.
[0004] The purpose of this utility model is achieved as follows: it includes a heavy benzene residual oil tank and a recovery tower. The recovery tower includes an upper section and a lower section connected together. The heavy benzene residual oil tank is connected to the lower section. The bottom of the lower section is provided with a wash oil outlet and a steam inlet. The wash oil outlet is connected to a wash oil storage tank through a pipeline. The steam inlet is connected to a steam superheater and a steam generator through a pipeline. The upper section has several trays arranged alternately inside. The upper part of the upper section is provided with a naphthalene oil outlet. The top of the upper section is provided with a crude benzene outlet. The crude benzene outlet is connected to a crude benzene cooler and a crude benzene storage tank in sequence through pipelines. The crude benzene outlet of the crude benzene storage tank is connected to the top of the upper section through a pipeline.
[0005] Furthermore, the crude benzene cooler is a water cooler, and the outlet of the crude benzene cooler is connected to the inlet of the steam generator through a circulation pipe.
[0006] Furthermore, a wash oil cooler is installed on the pipeline between the wash oil outlet and the wash oil storage tank. The wash oil cooler is a water cooler, and the water outlet of the wash oil cooler is connected to the water inlet of the steam generator through a pipeline.
[0007] Furthermore, a steam distributor is installed after the steam inlet extends into the lower section.
[0008] Furthermore, a thermocouple is installed in the lower section, and a solenoid valve is installed on the pipeline between the steam inlet and the steam superheater.
[0009] Furthermore, a jacket is provided on the outer wall of the lower section. The steam inlet of the jacket is connected to the steam superheater through a pipeline, and the steam outlet of the jacket is connected to the water inlet of the steam generator through a pipeline.
[0010] Furthermore, a stirrer is installed in the lower section.
[0011] This invention relates to the recovery and treatment of heavy benzene residue oil, a byproduct of benzene hydrogenation processes, particularly the recovery of crude benzene. During operation, the heavy benzene residue oil is stored in a heavy benzene residue oil tank and then fed into the lower section of a recovery tower. Simultaneously, a steam generator and a steam superheater are activated to generate superheated steam, which is then piped to the bottom of the lower section. The superheated steam mixes thoroughly with the heavy benzene residue oil in the lower section, heating it. Under the distillation separation action of the tower trays, the heavy benzene residue oil undergoes continuous distillation separation. The separated heavy component wash oil is discharged from the wash oil outlet and stored in a wash oil storage tank. The separated naphthalene oil is discharged from the naphthalene oil outlet, while the light component vapor and crude benzene are discharged from the crude benzene outlet and then cooled by a crude benzene cooler. The water vapor condenses into water, and the mixture of water and crude benzene enters the crude benzene storage tank. Due to their different densities, the water and crude benzene separate into layers within the crude benzene storage tank. The lower layer of water is discharged, yielding the crude benzene. In this invention, the traditional wash oil heater is eliminated, and the wash oil is no longer used to heat the heavy benzene residue. Instead, superheated steam is used to heat the heavy benzene residue. Compared to liquid-liquid heat transfer, steam heat transfer efficiency is higher, allowing for faster and more uniform heating of the heavy benzene residue, shortening the separation time, and thus improving the separation efficiency. This facilitates the separation of crude benzene, naphthalene oil, and wash oil from the heavy benzene residue, increases the crude benzene extraction rate, reduces the crude benzene reflux ratio, and the entire system can operate normally for a long period, exhibiting good operational stability. In summary, this invention has the advantages of good recovery effect, high extraction rate, and stable operation. Attached Figure Description
[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0013] In the diagram: 1-Heavy benzene residual oil tank, 2-Upper section, 3-Lower section, 4-Wash oil storage tank, 5-Steam superheater, 6-Steam generator, 7-Tray, 8-Naphthalene oil outlet, 9-Crude benzene cooler, 10-Crude benzene storage tank, 11-Circulation pipe, 12-Wash oil cooler, 13-Gas distributor, 14-Thermocouple, 15-Solenoid valve, 16-Jacket, 17-Agitator. Detailed Implementation
[0014] The present invention will be further described below with reference to the accompanying drawings, but this description is not intended to limit the present invention in any way. Any changes or improvements made based on the present invention shall fall within the protection scope of the present invention.
[0015] like Figure 1 As shown, this utility model includes a heavy benzene residual oil tank 1 and a recovery tower. The heavy benzene residual oil tank 1 is used to store heavy benzene residual oil generated in the benzene hydrogenation process. The recovery tower includes an upper section 2 and a lower section 3 connected together. The heavy benzene residual oil tank 1 is connected to the lower section 3. The bottom of the lower section 3 is provided with a wash oil outlet and a steam inlet. The wash oil outlet is connected to a wash oil storage tank 4 through a pipeline. The steam inlet is connected to a steam superheater 5 and a steam generator 6 through a pipeline. The steam generator 6 is used to generate saturated steam, and the steam superheater 5 is used to heat the saturated steam to obtain superheated steam. The superheated steam is used to heat the heavy benzene residual oil in the recovery tower. The upper section 2 has several trays 7 arranged alternately inside. The trays 7 are existing technology, and their main function is to provide sufficient contact surface for the gas and liquid phases to promote mass and heat transfer. This invention achieves the separation of the mixture. It is used to separate crude benzene, naphthalene oil, and wash oil from heavy benzene residue. The upper section 2 has a naphthalene oil outlet 8 at its upper part and a crude benzene outlet at its top. The crude benzene outlet is connected in sequence to a crude benzene cooler 9 and a crude benzene storage tank 10 via pipelines. The crude benzene cooler 9 is used to cool the crude benzene and steam; various types of heat exchangers can be used for ease of use. The crude benzene storage tank 10 is used to store the cooled crude benzene. In this invention, the cooled water and crude benzene separate into layers within the crude benzene storage tank 10, with water at the bottom and crude benzene at the top. Discharging the water at the bottom yields the crude benzene. The crude benzene outlet of the crude benzene storage tank 10 is connected to the top of the upper section 2 via a pipeline. Considering purity issues, a portion of the crude benzene can be returned to a recovery tower for further purification.
[0016] This invention relates to the recovery and treatment of heavy benzene residue oil, a byproduct of benzene hydrogenation processes, particularly the recovery of crude benzene. During operation, the heavy benzene residue oil is stored in a heavy benzene residue oil tank 1, and then fed into the lower section 3 of the recovery tower. Simultaneously, the steam generator 6 and the steam superheater 5 are activated to generate superheated steam, which is then piped to the bottom of the lower section 3. The superheated steam thoroughly mixes with the heavy benzene residue oil in the lower section 3, heating the oil and reducing its temperature. The residual oil undergoes continuous distillation separation under the action of the distillation separation in tray 7. The heavy component wash oil after separation is discharged from the wash oil outlet and stored in the wash oil storage tank 4. The separated naphthalene oil is discharged from the naphthalene oil outlet 8. The vapor of the light component and crude benzene are discharged from the crude benzene outlet and then cooled by the crude benzene cooler 9. The water vapor is condensed into water. The mixture of water and crude benzene enters the crude benzene storage tank 10 together. Due to the difference in density, water and crude benzene separate into layers in the crude benzene storage tank 10. The lower layer of water is discharged to obtain crude benzene.
[0017] In this invention, the traditional wash oil heater is eliminated, and the wash oil is no longer used to heat the heavy benzene residue. Instead, superheated steam is used to heat the heavy benzene residue. Compared with liquid-liquid heat transfer, steam heat transfer efficiency is higher, and it can heat the heavy benzene residue more quickly and evenly, shortening the separation time of the heavy benzene residue and thus improving the separation efficiency of the heavy benzene residue. This is beneficial for the separation of crude benzene, naphthalene oil and wash oil in the heavy benzene residue, improving the crude benzene extraction rate, reducing the crude benzene reflux ratio, and the entire system can operate normally for a long time with good operational stability.
[0018] The crude benzene cooler 9 is a water cooler. The outlet of the crude benzene cooler 9 is connected to the inlet of the steam generator 6 through the circulation pipe 11. The heavy benzene residual oil is separated and extracted in the recovery tower and discharged together with the water vapor. It needs to be cooled by the crude benzene cooler 9. In this utility model, the water vapor is condensed into water and discharged together with the crude benzene. The required cooling medium is water. The water absorbs the heat in the water vapor and crude benzene and then passes it into the steam generator 6, which can reduce the energy consumption of the steam generator 6 and play an energy-saving role. At the same time, it reduces the waste and loss of heat in the crude benzene and water vapor.
[0019] A wash oil cooler 12 is installed on the pipeline between the wash oil outlet and the wash oil storage tank 4. The wash oil cooler 12 is a water cooler. The water outlet of the wash oil cooler 12 is connected to the water inlet of the steam generator 6 through a pipeline. When the wash oil is discharged from the wash oil outlet, the temperature is high and it still contains a lot of heat. By setting up the wash oil cooler 12, the heat in the wash oil is absorbed and used to heat the water, raising the water temperature. Then the water is fed into the steam generator 6, which can reduce the energy consumption of the steam generator 6, play an energy-saving role, and at the same time avoid the waste and loss of heat in the wash oil.
[0020] A gas distributor 13 is installed after the steam inlet extends into the lower section. The gas distributor 13 is an existing structure used to disperse the superheated steam, dispersing the superheated steam throughout the horizontal plane of the entire recovery tower. This increases the contact area between the superheated steam and the heavy benzene residue oil, thereby improving the heating efficiency of the heavy benzene residue oil. At the same time, it avoids the problem of some heavy benzene residue oil being overheated while others are underheated, thus improving the uniformity of heating the heavy benzene residue oil.
[0021] A thermocouple 14 is installed in the lower section 3, and a solenoid valve 15 is installed on the pipeline between the steam inlet and the steam superheater 5. The thermocouple 14 is used to monitor the temperature of the heavy benzene residue in the recovery tower in real time to ensure that the temperature of the heavy benzene residue after heating is within the required temperature range, thereby ensuring the separation and extraction efficiency of the heavy benzene residue. The flow rate and flow of the steam introduced into the recovery tower are controlled by the solenoid valve 15, which is convenient for real-time adjustment to meet the heating requirements of the heavy benzene residue.
[0022] A jacket 16 is installed on the outer wall of the lower section 3. The steam inlet of the jacket 16 is connected to the steam superheater 5 via a pipeline, and the steam outlet of the jacket 16 is connected to the water inlet of the steam generator 6 via a pipeline. When this invention is in operation, some superheated steam is introduced into the jacket 16 to heat the heavy benzene residue oil from the outside of the recovery tower. This simultaneously heats the heavy benzene residue oil from both the outside and the inside, improving the heating efficiency and uniformity of the heavy benzene residue oil. Subsequently, the steam with a slightly lower temperature is returned to the steam generator 6, utilizing its own heat, reducing heat waste, and lowering the energy consumption for steam production.
[0023] A stirrer 17 is installed in the lower section 3. The stirrer 17 is an existing device. In this utility model, the stirrer 17 is used to stir the heavy benzene residue in the lower section 3 of the recovery tower, promote the further uniform mixing of water vapor and heavy benzene residue, prevent the problem of uneven heating of heavy benzene residue, improve the heating efficiency of heavy benzene residue, and promote the subsequent separation and extraction of heavy benzene residue.
Claims
1. A system for processing and recovering crude benzene from heavy benzene residue oil, comprising a heavy benzene residue oil tank (1) and a recovery tower, characterized in that: The recovery tower includes an upper section (2) and a lower section (3) connected together. The heavy benzene residual oil tank (1) is connected to the lower section (3). The bottom of the lower section (3) is provided with a wash oil outlet and a steam inlet. The wash oil outlet is connected to a wash oil storage tank (4) through a pipeline. The steam inlet is connected to a steam superheater (5) and a steam generator (6) through a pipeline. The upper section (2) is provided with several trays (7) arranged alternately inside. The upper part of the upper section (2) is provided with a naphthalene oil outlet (8). The top of the upper section (2) is provided with a crude benzene outlet. The crude benzene outlet is connected to a crude benzene cooler (9) and a crude benzene storage tank (10) in sequence through a pipeline. The crude benzene outlet of the crude benzene storage tank (10) is connected to the top of the upper section (2) through a pipeline.
2. The heavy benzene residue processing and crude benzene recovery system according to claim 1, characterized in that: The crude benzene cooler (9) is a water cooler, and the outlet of the crude benzene cooler (9) is connected to the inlet of the steam generator (6) through the circulation pipe (11).
3. The heavy benzene residue processing and crude benzene recovery system according to claim 1, characterized in that: A wash oil cooler (12) is installed on the pipeline between the wash oil outlet and the wash oil storage tank (4). The wash oil cooler (12) is a water cooler. The outlet of the wash oil cooler (12) is connected to the inlet of the steam generator (6) through a pipeline.
4. The heavy benzene residue processing and crude benzene recovery system according to claim 1, characterized in that: A steam distributor (13) is installed after the steam inlet extends into the lower section.
5. The heavy benzene residue processing and crude benzene recovery system according to claim 1, characterized in that: A thermocouple (14) is installed in the lower section (3), and a solenoid valve (15) is installed on the pipeline between the steam inlet and the steam superheater (5).
6. The heavy benzene residue processing and crude benzene recovery system according to claim 1, characterized in that: A jacket (16) is provided on the outer wall of the lower section (3). The steam inlet of the jacket (16) is connected to the steam superheater (5) through a pipeline, and the steam outlet of the jacket (16) is connected to the water inlet of the steam generator (6) through a pipeline.
7. The heavy benzene residue processing and crude benzene recovery system according to claim 1, characterized in that: A stirrer (17) is provided in the lower section (3).