Solvent recovery system for semi-coke wastewater treatment

Abstract

A solvent recovery system for semi-coke wastewater treatment comprises a phenol tower and an extraction tower, an extract output pipe of the extraction tower is connected with a liquid inlet of an extract tank, an output pipe of the extract tank is connected with an inlet of an extract pump set, and an outlet of the extract pump set is divided into two paths, one path enters a crude phenol heat exchanger to exchange heat with crude phenol output from the bottom of the phenol tower and then is conveyed to the phenol tower through an extract output pipe, and the other path enters an extract preheater to exchange heat with solvent gas output from the top of the phenol tower and then is conveyed to the phenol tower; the crude phenol tank conveys crude phenol to the crude phenol tank through a crude phenol pump set, the extract preheater outputs a solvent to the solvent condenser, and the solvent condenser outputs the solvent to the solvent tank. According to the utility model, the heat recovery and reutilization of the solvent in different stages are realized. The extract is preheated before entering the phenol tower, so that the extraction efficiency is improved, the dependence of the system on an external heat source is reduced, and the recovery efficiency of the solvent is remarkably improved.

Description

Technical Field

[0001] This utility model belongs to the technical field of wastewater treatment equipment, specifically relating to a solvent recovery system for treating semi-coke wastewater. Background Technology

[0002] The production of semi-coke generates a large amount of wastewater containing various harmful substances such as phenols, ammonia, and cyanide. This wastewater is complex in composition, highly toxic, and difficult to degrade. If discharged directly without treatment, it will cause serious environmental pollution. Currently, the treatment of semi-coke wastewater mainly employs physical, chemical, and biological methods. Solvent extraction is a common treatment method, which uses an extractant to separate organic compounds such as phenols from the wastewater, achieving wastewater purification and solvent recovery.

[0003] However, existing solvent recovery systems for semi-coke wastewater treatment have some shortcomings. On the one hand, the solvent recovery efficiency during the extraction process is low, leading to some solvent loss, which not only increases production costs but may also cause secondary pollution to the environment. On the other hand, the coordination between various devices in the system is poor, and there is a lack of effective flow and temperature control, making it difficult to guarantee the stability and reliability of the entire recovery process. In addition, existing systems consume a lot of energy during the treatment process and have strict requirements for wastewater pretreatment, limiting their widespread application in actual production. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a high-efficiency, energy-saving and stable solvent recovery system for treating semi-coke wastewater.

[0005] The technical solution adopted to solve the above-mentioned technical problems is: a solvent recovery system for treating semi-coke wastewater, including a phenol tower and an extraction tower. The extract output pipe of the extraction tower is connected to the inlet of the extract tank, and the extract tank output pipe is connected to the inlet of the extract pump group. The outlet of the extract pump group is divided into two paths. One path enters the crude phenol heat exchanger and exchanges heat with the crude phenol output from the bottom of the phenol tower, and then is transported to the phenol tower through the extract output pipe. The other path enters the extract preheater and exchanges heat with the solvent gas output from the top of the phenol tower, and then is input into the phenol tower. The crude phenol output pipe of the crude phenol heat exchanger is connected to the crude phenol tank. The crude phenol tank is transported to the crude phenol container through the crude phenol pump group. The solvent output from the extract preheater is sent to the solvent condenser, and the solvent condenser is sent to the solvent tank.

[0006] As a preferred technical solution, the solvent tank outputs two paths: one path sends the solvent back to the phenol tower via a phenol tower reflux pump group, and the other path sends the solvent to the extraction tower via a solvent circulation pump group.

[0007] As a preferred technical solution, a liquid level control valve is provided at the outlet of the extract pump group. The liquid level control valve regulates the flow rate of the two extracts. A liquid level sensor is provided on the extract tank, and the liquid level sensor is electrically connected to the liquid level control valve.

[0008] As a preferred technical solution, a temperature sensor is installed on the crude phenol output tube of the crude phenol heat exchanger, and a temperature transmitter is installed on the extract output tube of the crude phenol heat exchanger. The temperature sensor and the temperature transmitter are electrically connected.

[0009] The beneficial effects of this utility model are as follows:

[0010] By installing a crude phenol heat exchanger and an extract preheater, heat recovery and reuse of the solvent at different stages were achieved. Preheating the extract before it enters the phenol tower improves extraction efficiency, reduces the system's dependence on external heat sources, and significantly enhances solvent recovery efficiency.

[0011] A level control valve is installed at the outlet of the extract pump unit, and the level sensor is used for real-time monitoring and adjustment to ensure the stability of the extract flow. Furthermore, the configuration of temperature sensors and temperature transmitters in the crude phenol heat exchanger enables precise control of the heat exchange process, further improving the system's stability and reliability.

[0012] The system reduces energy consumption during the heating process by recycling heat. Simultaneously, the dual-output design of the solvent tank enables solvent recycling, reducing solvent loss and thus lowering production costs. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model.

[0014] The components include: 1. Phenol tower; 2. Extract preheater; 3. Solvent condenser; 4. Liquid level control valve; 5. Liquid level sensor; 6. Extract tank; 7. Extraction tower; 8. Extract pump group; 9. Crude phenol pump group; 10. Crude phenol tank; 11. Solvent circulation pump group; 12. Phenol tower reflux pump group; 13. Solvent tank; 14. Temperature sensor; 15. Crude phenol heat exchanger; and 16. Temperature transmitter. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the present invention is not limited to the following embodiments.

[0016] exist Figure 1In this embodiment, the solvent recovery system for treating semi-coke wastewater includes a phenol tower 1 and an extraction tower 7. The extract output pipe of the extraction tower 7 is connected to the inlet of the extract tank 6. A level sensor 5 is installed on the extract tank 6. The output pipe of the extract tank 6 is connected to the inlet of the extract pump group 8. A level control valve 4 is installed at the outlet of the extract pump group 8. The level control valve 4 is electrically connected to the level sensor 5. The extract is divided into two paths by the level control valve 4. One path enters the crude phenol heat exchanger 15 and exchanges heat with the crude phenol output from the bottom of the phenol tower 1. The crude phenol is then transported to the phenol tower 1 through the extract output pipe. A temperature transmitter 16 is installed on the extract output pipe of the crude phenol heat exchanger 15. The other path enters the extract preheater 2 and exchanges heat with the solvent gas output from the top of the phenol tower 1. The crude phenol output pipe of the crude phenol heat exchanger 15 is connected to the crude phenol tank 10. A temperature sensor 14 is installed on the crude phenol output pipe of the crude phenol heat exchanger 15. The temperature sensor 14 is electrically connected to the temperature transmitter 16. The crude phenol tank 10 transports crude phenol to the crude phenol tank via the crude phenol pump group 9. The extract preheater 2 outputs solvent to the solvent condenser 3. The solvent condenser 3 outputs solvent to the solvent tank 13. The solvent tank 13 outputs two paths: one path transports the solvent back to the phenol tower 1 via the phenol tower reflux pump group 12, and the other path transports the solvent to the extraction tower 7 via the solvent circulation pump group 11.

[0017] The working principle of this utility model is as follows:

[0018] The extract from extraction tower 7 enters extractant tank 6. The extract in extractant tank 6 is pumped by extractant pump group 8, which has two outlets: one enters crude phenol heat exchanger 15, where it exchanges heat with crude phenol output from the bottom of phenol tower 1, and the extracted extract after heat exchange is pumped back to phenol tower 1 through extractant outlet pipe; the other enters extractant preheater 2, where it exchanges heat with solvent gas output from the top of phenol tower 1, and the extracted extract after heat exchange is also input into phenol tower 1. The crude phenol outlet pipe of crude phenol heat exchanger 15 pumps the heated crude phenol to crude phenol tank 10, which then pumps the crude phenol to crude powder tank via crude powder pump group. The solvent gas output from extractant preheater 2 is condensed by solvent condenser 3, and the condensed solvent enters solvent tank 13. The solvent output from solvent tank 13 has two outlets: one returns the solvent to phenol tower 1 via phenol tower reflux pump group 12, and the other pumps the solvent back to extraction tower 7 via solvent circulation pump group 11, completing the solvent recycling process.

[0019] To ensure stable system operation, the level sensor 5 is linked with the level control valve 4. Based on the level signal in the extract tank 6 collected by the level sensor 5, the level control valve 4 automatically adjusts its opening to regulate the flow rate of the extract delivered to the extraction tower 7, thereby ensuring the stability of the level in the extract tank 6.

[0020] Temperature sensor 14 is linked with temperature transmitter 16. Temperature sensor 14 collects the temperature signal of crude phenol after heat exchange, and temperature transmitter 16 adjusts the flow rate of extract output from crude phenol heat exchanger 15 according to the temperature signal, thereby achieving precise control of the heat exchange process.

Claims

1. A solvent recovery system for treating semi-coke wastewater, comprising a phenol tower and an extraction tower, characterized in that: The extract output pipe of the extraction tower is connected to the inlet of the extract tank, and the extract tank output pipe is connected to the inlet of the extract pump group. The outlet of the extract pump group is divided into two paths. One path enters the crude phenol heat exchanger and exchanges heat with the crude phenol output from the bottom of the phenol tower before being transported to the phenol tower through the extract output pipe. The other path enters the extract preheater and exchanges heat with the solvent gas output from the top of the phenol tower before being input into the phenol tower. The crude phenol output pipe of the crude phenol heat exchanger is connected to the crude phenol tank. The crude phenol tank transports the crude phenol to the crude phenol container through the crude phenol pump group. The solvent output from the extract preheater is sent to the solvent condenser, and the solvent condenser outputs the solvent to the solvent tank.

2. The solvent recovery system for treating semi-coke wastewater according to claim 1, characterized in that: The solvent tank outputs two paths: one path sends the solvent back to the phenol tower via a phenol tower reflux pump set, and the other path sends the solvent to the extraction tower via a solvent circulation pump set.

3. The solvent recovery system for treating semi-coke wastewater according to claim 1, characterized in that: A level control valve is installed at the outlet of the extract pump set. The level control valve regulates the flow rate of the two extracts. A level sensor is installed on the extract tank. The level sensor is electrically connected to the level control valve.

4. The solvent recovery system for treating semi-coke wastewater according to claim 1, characterized in that: A temperature sensor is installed on the crude phenol output tube of the crude phenol heat exchanger, and a temperature transmitter is installed on the extract output tube of the crude phenol heat exchanger. The temperature sensor and the temperature transmitter are electrically connected.

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