Recycling device for aromatic hydrocarbon extraction sewage

Abstract

The utility model belongs to the technical field of chemical production, and particularly relates to an aromatic hydrocarbon extraction sewage recovery device which comprises an aromatic hydrocarbon raw material tank, a water cutting pipe is arranged on the aromatic hydrocarbon raw material tank, a solvent regeneration tower is arranged at the tail end of the water cutting pipe, and a steam pipe is arranged on the solvent regeneration tower. A solvent recovery tower is arranged at the tail end of the steam pipe, an extraction oil pipe and a circulating water pipe are arranged on the solvent recovery tower, an extraction oil tank is arranged at the tail end of the extraction oil pipe, and the circulating water pipe is connected with an aromatic hydrocarbon raw material tank. Compared with the prior art, the recovery device has the advantages that benzene-containing sewage is effectively recovered and treated, so that products such as benzene, methylbenzene and the like are recycled, the water consumption of the device is reduced, the environmental pollution risk is reduced, and the economic benefit and the environmental benefit are improved. The technical scheme is of great significance to sustainable development of the petrochemical industry.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical production, and particularly relates to a recovery device for aromatics extraction wastewater. Background Art

[0002] In the petrochemical industry, the aromatics extraction unit is an important unit for producing high-purity organic chemical raw materials such as benzene and toluene. However, during the aromatics extraction process, due to the particularity of the material properties and the complexity of the process operation, a certain amount of benzene-containing wastewater is often generated. This wastewater mainly comes from the water-cutting process of the aromatics raw material tank and contains a small amount of valuable products such as benzene and toluene.

[0003] The traditional treatment method is to directly discharge this benzene-containing wastewater into the sewage treatment system, which not only causes the loss of products such as benzene and toluene, reduces the economic benefits, but also brings potential pollution risks to the environment. In addition, the sewage treatment system requires additional water resources for dilution and treatment, increasing the water consumption and operating costs of the unit.

[0004] In summary, there is a certain market demand for designing a recovery device for aromatics extraction wastewater. Summary of the Invention

[0005] Aiming at the deficiencies of the above-mentioned prior art, the utility model provides a recovery device for aromatics extraction wastewater to solve the above problems.

[0006] A recovery device for aromatics extraction wastewater of the utility model includes an aromatics raw material tank, a water-cutting pipe is arranged on the aromatics raw material tank, a solvent regeneration tower is arranged at the end of the water-cutting pipe, a steam pipe is arranged on the solvent regeneration tower, a solvent recovery tower is arranged at the end of the steam pipe, an extraction oil pipe and a circulating water pipe are arranged on the solvent recovery tower, an extraction oil tank is arranged at the end of the extraction oil pipe, and the circulating water pipe is connected to the aromatics raw material tank.

[0007] Further, the internal pressure of the aromatics raw material tank is set to 0.15 MPa, and the internal pressure of the solvent regeneration tower is set to -10 KPa.

[0008] Further, flow meters are arranged on both the water-cutting pipe and the circulating water pipe.

[0009] Further, regulating valves are arranged on both the water-cutting pipe and the circulating water pipe.

[0010] Further, the water-cutting pipe, the steam pipe, the extraction oil pipe and the circulating water pipe are all 304 stainless steel pipes, and corrosion-resistant coatings are applied on both the inner and outer walls of the pipe walls.

[0011] Further, the solvent recovery tower includes a condenser, and the condenser is a shell-and-tube type.

[0012] Furthermore, the solvent regeneration tower includes a heating device, and the heating device is a thermosyphon reboiler.

[0013] Furthermore, a circulation pump is provided on the circulating water pipe.

[0014] Compared with the prior art, through the effective recovery and treatment of benzene-containing sewage, this recovery device realizes the recycling of products such as benzene and toluene. At the same time, it reduces the water consumption of the device, lowers the environmental pollution risk, and improves economic and environmental benefits. This technical solution is of great significance for the sustainable development of the petrochemical industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the present utility model.

[0016] In the figure: 1, aromatic hydrocarbon raw material tank; 2, water cutting pipe; 3, solvent regeneration tower; 4, steam pipe; 5, solvent recovery tower; 6, extraction oil pipe; 7, circulating water pipe; 8, extraction oil tank; 9, flowmeter; 10, regulating valve; 11, circulation pump. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] To better understand the present utility model, the following will Figure 1 be used to explain in detail the embodiments of the present utility model.

[0018] It should be noted that the "front, rear, left, right, up, and down" directions described in the text are all based on the Figure 1 "front, rear, left, right, up, and down" directions in

[0019] See Figure 1 , a recovery device for aromatic hydrocarbon extraction sewage of the present utility model includes an aromatic hydrocarbon raw material tank 1, a water cutting pipe 2 is provided on the aromatic hydrocarbon raw material tank 1, a solvent regeneration tower 3 is provided at the end of the water cutting pipe 2, a steam pipe 4 is provided on the solvent regeneration tower 3, a solvent recovery tower 5 is provided at the end of the steam pipe 4, an extraction oil pipe 6 and a circulating water pipe 7 are provided on the solvent recovery tower 5, an extraction oil tank 8 is provided at the end of the extraction oil pipe 6, and the circulating water pipe 7 is connected to the aromatic hydrocarbon raw material tank 1.

[0020] In a preferred technical solution, in order to be able to transport the wastewater from the aromatic hydrocarbon raw material tank 1 to the solvent regeneration tower 3, the internal pressure of the aromatic hydrocarbon raw material tank 1 is set to 0.15 MPa, and the internal pressure of the solvent regeneration tower 3 is set to -10 KPa. By using the pressure difference between the raw material tank and the regeneration tower (the difference between 0.15 MPa and -10 KPa), the benzene-containing sewage is smoothly transported to the solvent regeneration tower 3.

[0021] Preferred technical solution: In the recovery device for aromatics extraction wastewater, flow meters 9 are provided on both the cut-off water pipe 2 and the circulating water pipe 7. These flow meters 9 are used to monitor and control the flow rates of wastewater and circulating water in real time. Through the flow meters 9, operators can accurately understand the discharge rate of wastewater and the return rate of circulating water, thus ensuring the stable operation and efficient recovery of the system.

[0022] Preferred technical solution: Control valves 10 are installed on both the cut-off water pipe 2 and the circulating water pipe 7. These control valves 10 allow operators to precisely control the flow rate. According to actual needs, operators can adjust the opening degree of the control valves 10 to change the flow rate of wastewater or circulating water. This is of great significance for optimizing system performance, ensuring product quality, and controlling resource consumption.

[0023] Preferred technical solution: The cut-off water pipe 2, steam pipe 4, extraction oil pipe 6, and circulating water pipe 7 are all made of 304 stainless steel pipes. 304 stainless steel has good corrosion resistance, high-temperature resistance, and strength, and is suitable for the complex working conditions in the aromatics extraction wastewater recovery device. In addition, to further improve the corrosion resistance of the pipes, corrosion-resistant coatings are applied on both the inner and outer walls of the pipes. This coating can effectively resist chemical corrosion and oxidation corrosion, and extend the service life of the pipes.

[0024] Preferred technical solution: The condenser in the solvent recovery tower 5 adopts a shell-and-tube design. The shell-and-tube condenser has a large heat transfer area and high heat transfer performance, and can quickly condense the stripping steam into liquid. This design helps to improve the solvent recovery efficiency and reduce energy consumption.

[0025] Preferred technical solution: The heating device in the solvent regeneration tower 3 adopts a thermosyphon reboiler. The thermosyphon reboiler uses the principle of natural circulation of liquid for heating without an external power source. It has the advantages of simple structure, convenient operation, safety and reliability, etc. During the solvent regeneration process, the thermosyphon reboiler can uniformly heat the wastewater and promote the vaporization and recovery of the solvent.

[0026] Preferred technical solution: To ensure the smooth flow and efficient utilization of circulating water, a circulating pump 11 is installed on the circulating water pipe 7. The circulating pump 11 can generate sufficient pressure to transport the treated clean water back to the aromatics raw material tank 1 for recycling. This design helps to reduce water resource waste and lower production costs.

[0027] Usage method and principle of the present utility model: The internal pressure of the aromatic hydrocarbon raw material tank 1 is set to 0.15 MPa, and the internal pressure of the solvent regeneration tower 3 is set to -10 KPa. The water cutting pipe 2 is connected to the vent of the solvent return line flowmeter 9 of the solvent regeneration tower 3. By using the pressure difference between the raw material tank and the regeneration tower (the difference between 0.15 MPa and -10 KPa), the benzene-containing sewage is smoothly transported to the solvent regeneration tower 3. The water vaporizes in the solvent regeneration tower 3 and becomes the stripping steam transported to the solvent recovery tower 5 through the steam pipe 4.

[0028] The solvent recovery tower 5 uses the distillation principle. By controlling the temperature and pressure, different components in the mixed solvent are separated according to the boiling point difference. Benzene and toluene can be condensed at relatively low temperatures and pressures due to their low boiling points. In the condensed liquid, solvents such as benzene and toluene are recovered to the extraction oil tank 8 through the extraction oil pipe 6, while the remaining wastewater returns to the aromatic hydrocarbon raw material tank 1 through the circulating water pipe 7 for recycling.

[0029] Through this recovery device, the effective recovery and recycling of benzene-containing sewage generated in the aromatic hydrocarbon extraction process can be achieved, which not only reduces product loss and environmental pollution, but also saves water resources and realizes the maximum utilization of resources.

[0030] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In the description of the present utility model, unless otherwise specified and limited, it should be noted that the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the communication inside two elements. It can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0031] The above is only the preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A recovery device for aromatics extraction wastewater, characterized in that: The invention comprises an aromatic raw material tank (1), wherein a water cut-off pipe (2) is arranged on the aromatic raw material tank (1), a solvent regeneration tower (3) is arranged at the end of the water cut-off pipe (2), a steam pipe (4) is arranged on the solvent regeneration tower (3), a solvent recovery tower (5) is arranged at the end of the steam pipe (4), an oil extraction pipe (6) and a circulating water pipe (7) are arranged on the solvent recovery tower (5), an oil extraction tank (8) is arranged at the end of the oil extraction pipe (6), and the circulating water pipe (7) is connected to the aromatic raw material tank (1).

2. A recovery device for aromatics extraction wastewater as claimed in claim 1, characterized in that: The internal pressure of the aromatic hydrocarbon raw material tank (1) is greater than the internal pressure of the solvent regeneration tower (3).

3. A recovery device for aromatics extraction wastewater as claimed in claim 1, characterized in that: The water cutting pipe (2) and the circulating water pipe (7) are both provided with flow meters (9).

4. A recovery device for aromatics extraction wastewater as claimed in claim 1, characterized in that: The water cut-off pipe (2) and the circulating water pipe (7) are both provided with regulating valves (10).

5. A recovery device for aromatics extraction wastewater as claimed in claim 1, characterized in that: The water cutting pipe (2), steam pipe (4), oil extraction pipe (6) and circulating water pipe (7) are all 304 stainless steel pipes, and the inner and outer surfaces of the pipe walls are coated with corrosion-resistant coatings.

6. A recovery device for aromatics extraction wastewater as claimed in claim 1, characterized in that: The solvent recovery tower (5) comprises a condenser, and the condenser is of a shell-and-tube type.

7. A recovery device for aromatics extraction wastewater as claimed in claim 1, characterized in that: The solvent regeneration tower (3) comprises a heating device, which is a thermosyphon reboiler.

8. A recovery device for aromatics extraction wastewater as claimed in claim 1, characterized in that: The circulating water pipe (7) is provided with a circulating pump (11).

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