Waste heat recycling system of coal tar hydrogenation device for chemical industry

Abstract

The utility model belongs to the technical field of chemical engineering, and discloses a waste heat recycling system of a coal tar hydrogenation device for chemical engineering. The system comprises a hydrogenation device consisting of a diesel medium-pressure and liquid-phase hydrogenation and diesel low-pressure steam generator, and is matched with a hot vertical deaerator and a steam condensate input pipeline. The steam generators converge steam condensate to the input pipeline through the steam branch pipes and the drain valves, the steam condensate flows into the hot vertical deaerator, demineralized water is connected into the deaerator, and the demineralized water is divided into three paths to be sent back to the steam generators through the water pump after deoxygenation. Meanwhile, the 0.6 Mpa steam output pipeline supplies energy to the deaerator, a backflow pipeline is arranged at an outlet of the water pump, and a key pipeline is provided with an adjusting valve. The system effectively solves the problem of waste heat waste of the existing coal tar hydrogenation device, improves the energy utilization rate and reduces the cost through steam condensate circulation, and is reasonable in layout and complete in function.

Description

Technical Field

[0001] This utility model relates to the field of chemical technology, and in particular to a waste heat recovery and utilization system for a coal tar hydrogenation device for chemical applications. Background Technology

[0002] Coal tar hydrogenation technology modifies coal tar through hydrogenation processes. Under specific temperature, pressure, and catalyst conditions, reactions such as desulfurization and unsaturated hydrocarbon saturation occur to improve its properties and obtain naphtha and high-quality fuel oil. However, coal tar hydrogenation units generate a large amount of waste heat during operation. If this waste heat is not recovered and utilized, it will not only waste energy but also cause thermal pollution to the environment. Waste heat has high energy value; its recovery and utilization can improve the energy efficiency of the unit, reduce the energy procurement costs for enterprises, and the low operation and maintenance costs of waste heat recovery units can save costs for enterprises and improve economic benefits. At the same time, reducing waste heat emissions also has positive significance for environmental protection. Utility Model Content

[0003] To address the aforementioned technical problems, this utility model provides a waste heat recovery and utilization system for a coal tar hydrogenation unit used in chemical industry, which solves the problem that waste heat cannot be recovered and utilized during the production process of existing coal tar hydrogenation units.

[0004] To achieve the above objectives, the technical solution of this utility model is as follows:

[0005] A waste heat recovery system for a coal tar hydrogenation unit used in chemical industry includes a coal tar hydrogenation unit, which comprises a medium-pressure diesel steam generator, a liquid-phase hydrogenation steam generator, and a low-pressure diesel steam generator. It also includes a vertical thermal deaerator and a steam condensate inlet pipeline. The 2.5 MPa steam output pipeline of the medium-pressure diesel steam generator is connected to a 2.5 MPa steam main pipe, which is connected to a 2.5 MPa steam condensate pipeline. The 1.0 MPa steam output pipeline of the liquid-phase hydrogenation steam generator is connected to a 1.0 MPa steam main pipe, which is connected to a 1.0 MPa steam condensate pipeline. The 0.6 MPa steam output pipeline of the low-pressure diesel steam generator is connected to a 0.6 MPa steam main pipe, which is connected to a... The 0.6 MPa steam condensate pipeline, 2.5 MPa steam condensate pipeline, 1.0 MPa steam condensate pipeline, and 0.6 MPa steam condensate pipeline are connected to one end of the steam condensate input pipeline. A 2.5 MPa steam trap, a 1.0 MPa steam trap, and a 0.6 MPa steam trap are installed on the 2.5 MPa, 1.0 MPa, and 0.6 MPa steam condensate pipelines, respectively. The other end of the steam condensate input pipeline is connected to the inlet of the vertical thermal deaerator. The vertical thermal deaerator is connected to a demineralized water input pipeline. The outlet of the vertical thermal deaerator is connected to a deoxygenated water pump. The outlet pipeline of the deoxygenated water pump is divided into three branches, which are respectively connected to the deoxygenated water inlet pipelines of the diesel medium-pressure steam generator, the liquid-phase hydrogenation steam generator, and the diesel low-pressure steam generator.

[0006] Furthermore, the 0.6 MPa steam output pipeline is also connected to a 0.6 MPa deaerator steam pipeline, which is connected to a thermal vertical deaerator.

[0007] Furthermore, a return pipe is connected to the outlet pipe of the deaerator pump, and the return pipe is connected to the thermal vertical deaerator.

[0008] Furthermore, regulating valves are installed on the return pipeline and the deoxygenated water inlet pipelines of the diesel medium-pressure steam generator, the liquid-phase hydrogenation steam generator, and the diesel low-pressure steam generator.

[0009] Compared with existing technologies, the beneficial effects of this utility model are as follows: By recovering the steam condensate generated by the diesel medium-pressure steam generator, liquid-phase hydrogenation steam generator, and diesel low-pressure steam generator, and then sending it back to each steam generator as deoxygenated water through a thermal vertical deaerator and deoxygenated water pump, waste heat is recycled, improving energy utilization efficiency and reducing energy waste; the system components are tightly connected and rationally laid out; the installation of 2.5Mpa steam traps, 1.0Mpa steam traps, and 0.6Mpa steam traps effectively prevents steam leakage and ensures smooth recovery of steam condensate; the installation of 0.6Mpa deoxygenated steam pipeline and return pipeline further improves the system's function, making the deoxygenation process more efficient and stable; the recovery and utilization of waste heat reduces the enterprise's dependence on external energy and lowers energy procurement costs. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of this utility model;

[0011] In the picture:

[0012] 1. Coal tar hydrogenation unit; 2. Medium-pressure diesel steam generator; 3. Liquid-phase hydrogenation steam generator; 4. Low-pressure diesel steam generator; 5. Vertical thermal deaerator; 6. Steam condensate inlet pipeline; 7. 2.5 MPa steam outlet pipeline; 8. 2.5 MPa steam condensate pipeline; 9. 1.0 MPa steam outlet pipeline; 10. 1.0 MPa steam condensate pipeline; 11. 0.6 MPa steam outlet pipeline; 12. 0.6 MPa steam condensate pipeline Line; 13, 2.5Mpa steam trap; 14, 1.0Mpa steam trap; 15, 0.6Mpa steam trap; 16, demineralized water inlet pipe; 17, deoxygenated water pump; 18, outlet pipe; 19, deoxygenated water inlet pipe; 20, 0.6Mpa deoxygenated steam pipe; 21, return pipe; 22, regulating valve; 23, 2.5Mpa steam main pipe; 24, 1.0Mpa steam main pipe; 25, 0.6Mpa steam main pipe. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this utility model. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of this utility model.

[0014] A waste heat recovery system for a coal tar hydrogenation unit in chemical industry includes a coal tar hydrogenation unit 1, which consists of a diesel medium-pressure steam generator 2, a liquid-phase hydrogenation steam generator 3, and a diesel low-pressure steam generator 4. It also includes a vertical thermal deaerator 5 and a steam condensate inlet pipe 6. The 2.5 MPa steam output pipe 7 of the diesel medium-pressure steam generator 2 is connected to a 2.5 MPa steam main pipe 23, and a 2.5 MPa steam condensate line 8 is connected to the 2.5 MPa steam main pipe 23. The 1.0 MPa steam output pipe 9 of the liquid-phase hydrogenation steam generator 3 is connected to a 1.0 MPa steam main pipe 24, and a 1.0 MPa steam condensate line 10 is connected to the 1.0 MPa steam main pipe 24. The 0.6 MPa steam output pipe 11 of the diesel low-pressure steam generator 4 is connected to a 0.6 MPa steam main pipe 25, and a 0.6 MPa steam condensate line 10 is connected to the 0.6 MPa steam main pipe 25. The 2.5MPa steam condensate pipeline 12, the 2.5MPa steam condensate pipeline 8, the 1.0MPa steam condensate pipeline 10, and the 0.6MPa steam condensate pipeline 12 are connected to one end of the steam condensate input pipeline 6. The 2.5MPa steam condensate pipeline 8, the 1.0MPa steam condensate pipeline 10, and the 0.6MPa steam condensate pipeline 12 are respectively equipped with a 2.5MPa steam trap 13, a 1.0MPa steam trap 14, and a 0.6MPa steam trap 15. The other end of the steam condensate input pipeline 6 is connected to the inlet of the thermal vertical deaerator 5. The thermal vertical deaerator 5 is connected to a demineralized water input pipeline 16. The outlet of the thermal vertical deaerator 5 is connected to a deoxygenated water pump 17. The outlet pipeline 18 of the deoxygenated water pump 17 is divided into three branches, which are respectively connected to the deoxygenated water inlet pipeline 19 of the diesel medium-pressure steam generator 2, the liquid phase hydrogenation steam generator 3, and the diesel low-pressure steam generator 4.

[0015] The 0.6 MPa steam output pipe 11 is also connected to a 0.6 MPa deoxygenated steam pipe 20, which is connected to the thermal vertical deaerator 5. When the thermal vertical deaerator 5 is performing deoxygenation, the heat of the 0.6 MPa steam can be used to assist the deoxygenation process, further improve the deoxygenation efficiency, and ensure the quality of the deoxygenated water entering each steam generator.

[0016] A return pipe 21 is connected to the outlet pipe 18 of the deoxygenated water pump 17. The return pipe 21 is connected to the thermal vertical deaerator 5. When the pressure, flow rate and other parameters of the deoxygenated water in the system fluctuate, the deoxygenated water can be adjusted through the return pipe 21 to make the system operation more stable.

[0017] A regulating valve 22 is installed on the return pipe 21 and the deoxygenated water inlet pipe 19 of the diesel medium-pressure steam generator 2, the liquid-phase hydrogenation steam generator 3, and the diesel low-pressure steam generator 4. The regulating valve 22 can precisely control the flow rate and pressure of the deoxygenated water in each pipe, ensuring that each steam generator operates under optimal conditions, and also facilitates flexible adjustment of system parameters according to actual production needs.

[0018] Other branch pipes can be connected to the 2.5 MPa steam main pipe 23, the 1.0 MPa steam main pipe 24, and the 0.6 MPa steam main pipe 25 to heat and exchange the steam generated by the diesel medium-pressure steam generator 2, the liquid phase hydrogenation steam generator 3, and the diesel low-pressure steam generator 4 for other systems in the hydrogenation unit.

[0019] When using:

[0020] The steam condensate generated by the 0.6 MPa steam output pipe 11 through the 0.6 MPa steam trap 15, the steam condensate generated by the 1.0 MPa steam pipe 9 through the 1.0 MPa steam trap 14, and the steam condensate generated by the 2.5 MPa steam pipe 7 through the 2.5 MPa steam trap 13 are all sent to the thermal vertical deaerator 5 for collection through the steam condensate input pipe 6.

[0021] The demineralized water is fed into the demineralized water input pipe 16 and the hot vertical deaerator 5. The steam condensate from the steam condensate input pipe 6 and the steam from the 0.6 MPa deaeration steam pipe 20 heat the demineralized water to remove dissolved oxygen. Then it is sent to the deaeration water pump 17 for pressurization. After pressurization, it is sent to the deaeration water inlet pipe 19 of the diesel medium-pressure steam generator 2, the liquid phase hydrogenation steam generator 3 and the diesel low-pressure steam generator 4 through the outlet pipe 18 of the deaeration water pump 17.

[0022] By installing regulating valves 22 on the return pipe 21 and the deoxygenated water inlet pipes 19 of the diesel medium-pressure steam generator 2, the liquid phase hydrogenation steam generator 3, and the diesel low-pressure steam generator 4, the water volume of the steam generator can be regulated.

[0023] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A waste heat recovery and utilization system for a coal tar hydrogenation unit for chemical use, comprising a coal tar hydrogenation unit (1), wherein the coal tar hydrogenation unit (1) is composed of a diesel medium-pressure steam generator (2), a liquid-phase hydrogenation steam generator (3), and a diesel low-pressure steam generator (4), characterized in that: It also includes a vertical thermal deaerator (5) and a steam condensate inlet pipe (6). The 2.5 MPa steam output pipe (7) of the diesel medium-pressure steam generator (2) is connected to a 2.5 MPa steam main pipe (23). The 2.5 MPa steam main pipe (23) is connected to a 2.5 MPa steam condensate line (8). The 1.0 MPa steam output pipe (9) of the liquid phase hydrogenation steam generator (3) is connected to a 1.0 MPa steam main pipe (24). The 1.0 MPa steam main pipe (24) is connected to a 1.0 MPa steam condensate line (10). The 0.6 MPa steam output pipe (11) of the diesel low-pressure steam generator (4) is connected to a 0.6 MPa steam main pipe (25). The 0.6 MPa steam main pipe (25) is connected to a 0.6 MPa steam condensate line (12). The 2.5 MPa steam condensate line (8) and the 1.0 MPa steam condensate line (10) are also connected. And the 0.6Mpa steam condensate pipeline (12) is connected to one end of the steam condensate input pipeline (6). The 2.5Mpa steam condensate pipeline (8), the 1.0Mpa steam condensate pipeline (10) and the 0.6Mpa steam condensate pipeline (12) are respectively equipped with 2.5Mpa steam traps (13), 1.0Mpa steam traps (14) and 0.6Mpa steam traps (15). The steam condensate input pipeline (6) The other end is connected to the inlet of the hot vertical deaerator (5). The hot vertical deaerator (5) is connected to the demineralized water input pipe (16). The outlet of the hot vertical deaerator (5) is connected to the deoxygenated water pump (17). The outlet pipe (18) of the deoxygenated water pump (17) is divided into three branches, which are respectively connected to the deoxygenated water inlet pipe (19) of the diesel medium-pressure steam generator (2), the liquid phase hydrogenation steam generator (3) and the diesel low-pressure steam generator (4).

2. The coal tar hydrogenation device waste heat recovery and utilization system for chemical industry according to claim 1, characterized in that: The 0.6 MPa steam output pipe (11) is also connected to the 0.6 MPa deoxygenated steam pipe (20), which is connected to the thermal vertical deaerator (5).

3. The coal tar hydrogenation device waste heat recovery and utilization system for chemical industry according to claim 2, characterized in that: A return pipe (21) is connected to the outlet pipe (18) of the deaerator (17), and the return pipe (21) is connected to the thermal vertical deaerator (5).

4. The coal tar hydrogenation device waste heat recovery and utilization system for chemical industry according to claim 3, characterized in that: A regulating valve (22) is installed on the deoxygenated water inlet pipe (19) of the return pipe (21) and the diesel medium-pressure steam generator (2), the liquid phase hydrogenation steam generator (3), and the diesel low-pressure steam generator (4).

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