Coal tar full-fraction hydrogenation system capable of recycling vacuum overhead oil

Abstract

According to the coal tar full-fraction hydrogenation system capable of recycling vacuum overhead oil, the coal tar to be treated is subjected to hydrotreatment through the pre-treatment unit, the hydrogenated coal tar is heated by the heating device, and the flow of the hydrogenated coal tar entering the vacuum tower is controlled; system overload is prevented from affecting the separation effect, vacuum top oil is formed at the top of the vacuum tower, and a vacuum first-line output device is used for obtaining diesel oil components from the vacuum tower; the distillation range and components of the vacuum overhead oil treated by the vacuum tower are close to those of a diesel oil component, so that the vacuum overhead oil and the diesel oil component subjected to vacuum fractionation are mixed and fed into a tank area unit for storage and subsequent application. According to the coal tar full-fraction hydrogenation system disclosed by the utility model, vacuum overhead oil and diesel oil components are mixed and are directly stored and utilized, so that the technical problems that the vacuum overhead oil is used as an unqualified product and is repeatedly processed and treated in the prior art, the system is complicated, and the energy consumption of the device is increased are solved.

Description

Technical Field

[0001] This utility model belongs to the field of coal tar hydrogenation technology, specifically relating to a coal tar full-fraction hydrogenation system that can recycle top oil. Background Technology

[0002] Coal tar full-fraction hydrogenation is an advanced technology that transforms coal tar into clean fuels and chemical raw materials through deep processing. Its core principle is to remove metal impurities, ash, and heteroatoms such as sulfur, nitrogen, and oxygen from coal tar through hydrogenation reactions, while saturating olefins and aromatics, thereby obtaining products such as diesel and naphtha that meet national standards, significantly improving resource utilization.

[0003] In the process of full-fraction hydrotreating of coal tar, top distillate is a common byproduct. It is the light fraction with a lower boiling point that is collected from the top of the vacuum distillation tower during the vacuum distillation of coal tar.

[0004] In existing coal tar full-fraction hydrotreating systems, the top oil is generally sent back to the tank farm as a substandard product and reprocessed in subsequent coal tar full-fraction hydrotreating processes. This process involves repeated processing, which increases the energy consumption of the unit. Utility Model Content

[0005] To address the technical problem in the existing coal tar full-fraction hydrogenation system that treats top-load oil as a defective product and repeatedly processes it, leading to system complexity and increased energy consumption, this invention provides a coal tar full-fraction hydrogenation system that can recycle top-load oil.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A coal tar full-fraction hydrogenation system with recyclable top oil, comprising: a pretreatment unit, a heating device, a vacuum tower, a top oil output device, a vacuum line output device, and a tank farm unit;

[0008] The pre-processing unit is connected to the heating device and is used to perform hydrogenation pre-treatment on the coal tar to be processed to obtain hydrogenated coal tar.

[0009] The heating device is connected to the pressure reducing tower and is used to heat the hydrogenated coal tar to above 370°C.

[0010] A flow control valve is provided between the pressure reducing tower and the heating device to ensure that the flow rate of hydrogenated coal tar entering the pressure reducing tower does not exceed 50t / h.

[0011] The pressure reducing oil output device is connected to the top of the pressure reducing tower;

[0012] The reduced pressure output device is connected to the pressure reducing tower and is also connected to the tank area unit via an output pipeline for outputting diesel components;

[0013] The top oil output device is connected to the output pipeline.

[0014] Optionally, the top oil output device includes a vacuuming component and a separation component;

[0015] The vacuum pumping assembly is connected to the top of the pressure reducing tower, and is used to maintain the pressure at the top of the pressure reducing tower at 2 kPa to 14 kPa, and to extract the pressure reducing oil from the top of the tower.

[0016] The separation component connects the vacuuming component and the output pipeline, and is used to separate the top oil and mix it with the diesel components before it enters the tank area unit.

[0017] Optionally, the separation assembly includes an oil-water separator and a condensate pump, the oil-water separator being connected to the vacuum assembly and the output pipeline;

[0018] The condensate pump is connected to the oil-water separator and also to the condensate circulation pipeline.

[0019] Optionally, the separation assembly further includes a non-condensable gas output assembly, which is connected to the oil-water separator and the vacuum assembly, and is also connected to the gas pipeline network.

[0020] Optionally, the coal tar full-fraction hydrogenation system also includes a bottom oil output device, a second-stage oil output device, and a storage device;

[0021] The reduced oil output device is connected to the bottom of the pressure reducing tower and the storage device, and is used to output oil residue to the storage device;

[0022] The reduced pressure output device is connected to the reduced pressure tower and the storage device, and is used to output wax oil components to the storage device.

[0023] Optionally, the heating device is a pressure-reducing furnace.

[0024] Optionally, a flow valve is provided between the top oil output device and the output pipeline, and the top oil output device is also connected to the top oil storage unit.

[0025] The beneficial effects of this utility model are:

[0026] This invention provides a coal tar full-fraction hydrogenation system for the recyclable top-oil of coal tar. After hydrogenation treatment of the coal tar to be processed in a pretreatment unit, the hydrogenated coal tar is heated to 370°C using a heating device. The flow rate of the hydrogenated coal tar entering the vacuum distillation tower is controlled to prevent system overload and ensure effective separation. In the vacuum distillation tower, the hydrogenated coal tar undergoes vacuum fractionation, forming top-oil at the top. A diesel component is also obtained from the vacuum distillation tower using a first-line output device. Since the top-oil after vacuum distillation has a distillation range and composition close to that of diesel, the vacuum fractionated top-oil and diesel component are mixed and sent to a tank farm unit for storage and subsequent application. This coal tar full-fraction hydrogenation system directly mixes the top-oil and diesel component for storage and utilization, avoiding the technical problems of treating the top-oil as a substandard product and repeatedly processing it, which leads to system complexity and increased energy consumption. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the coal tar full-fraction hydrogenation system for recyclable top oil in this utility model;

[0028] Figure 2 This is a further schematic diagram of the coal tar full-fraction hydrogenation system of this utility model;

[0029] Figure 3 This is a schematic diagram of the top oil output device in this utility model.

[0030] The components include: 1. Pre-treatment unit; 2. Heating device; 21. Flow control valve; 3. Pressure reducing tower; 4. Pressure reducing top oil output device; 41. Vacuuming assembly; 42. Separation assembly; 421. Oil-water separator; 422. Condensate pump; 423. Non-condensable gas output assembly; 43. Conductor valve; 401. Condensate circulation pipeline; 402. Gas pipeline network; 5. Pressure reducing first line output device; 51. Output pipeline; 6. Tank farm unit; 7. Pressure reducing bottom oil output device; 8. Pressure reducing second line output device; 9. Storage device; 10. Pressure reducing top oil storage unit. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this utility model or its application or use. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0033] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0034] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0035] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0036] See Figure 1This paper illustrates a schematic diagram of a coal tar full-fraction hydrogenation system with recyclable top oil according to this application, including: a pretreatment unit 1, a heating device 2, a vacuum tower 3, a top oil output device 4, a first-line vacuum oil output device 5, and a tank area unit 6; the pretreatment unit 1 is connected to the heating device 2 for hydrogenation pretreatment of the coal tar to be treated, to obtain hydrogenated coal tar; the heating device 2 is connected to the vacuum tower 3 for heating the hydrogenated coal tar to above 370°C; a flow control valve 21 is installed between the vacuum tower 3 and the heating device 2 to ensure that the flow rate of hydrogenated coal tar entering the vacuum tower 3 does not exceed 50 t / h; the top oil output device 4 is connected to the top of the vacuum tower 3; the first-line vacuum oil output device 5 is connected to the vacuum tower 3 and, through an output pipeline 51, to the tank area unit 6 for outputting diesel components; the top oil output device 4 is connected to the output pipeline 51.

[0037] In this embodiment, after the coal tar to be treated is hydrogenated by the pretreatment unit 1, the hydrogenated coal tar is heated to 370°C using the heating device 2. The flow rate of the hydrogenated coal tar entering the vacuum distillation tower 3 is controlled to achieve fine separation of all coal tar components, while preventing system overload from affecting the separation effect. The hydrogenated coal tar undergoes vacuum fractionation in the vacuum distillation tower 3, forming a top fraction oil at the top of the tower. Diesel components are obtained from the vacuum distillation tower 3 using the first-line output device 4. The top fraction oil after vacuum distillation has a distillation range and composition close to that of diesel components. Therefore, the top fraction oil and diesel components are mixed and sent to the tank area unit 6 for storage and subsequent application. The coal tar full-fraction hydrogenation system of this invention mixes the top fraction oil and diesel components for direct storage and utilization, avoiding the technical problems of treating the top fraction oil as a substandard product and repeatedly processing it, leading to system complexity and increased energy consumption in existing technologies.

[0038] Specifically, the pretreatment unit 1 can use a fixed-bed hydrogenation reactor to hydrogenate coal tar, removing impurities such as sulfur, nitrogen, and metals from the coal tar; the hydrogenated coal tar is heated to 370°C to 400°C using a heating device 2, and its flow rate is controlled by a flow control valve 21, and fractionated in a vacuum distillation tower to obtain top-distillation oil, first-line diesel oil, second-line wax oil, and bottom-distillation residue; the top-distillation oil and diesel components are mixed in the output pipeline 51 and then sent to the tank area to mix the top-distillation oil and diesel components, thereby improving oil utilization and reducing waste.

[0039] Optionally, refer to Figure 2The top oil output device 4 of this utility model includes a vacuum assembly 41 and a separation assembly 42; the vacuum assembly 41 is connected to the top of the pressure reducing tower 3 and is used to make the pressure at the top of the pressure reducing tower 3 between 2KPa and 14KPa and to extract the top oil; the separation assembly 42 is connected to the vacuum assembly 41 and the output pipeline 51 and is used to separate the top oil and mix it with the diesel components before entering the tank area unit 6.

[0040] In this embodiment, the vacuum pumping component 41 is used to control the pressure at the top of the pressure reducing tower 3 to 2-14 kPa, combining high temperature (≥370℃) and low pressure (≤14 kPa) to achieve fine separation of all components of coal tar; the separation component 42 is used to separate oil, water and non-condensable gas from the top oil of the pressure reducing tower to prevent water and gas from mixing into the diesel.

[0041] Optionally, refer to Figure 3 The separation component 42 in this utility model includes an oil-water separator 421 and a condensate pump 422. The oil-water separator 421 is connected to the vacuum assembly 41 and the oil-water separator 421 is connected to the output pipeline 51. The condensate pump 422 is connected to the oil-water separator 421 and the condensate circulation pipeline 401.

[0042] In this embodiment, the oil-water separator 421 is used to separate the extracted light oil gas into oil, water and non-condensable gases; the generated condensate is sent into the condensate circulation pipeline for device cooling or steam generation.

[0043] Optionally, the separation component 42 in this utility model further includes a non-condensable gas output component 423, which is connected to the oil-water separator 421 and the vacuum component 41, and is also connected to the gas pipeline network 402.

[0044] In this embodiment, the non-condensable gas (containing hydrogen and light hydrocarbons) separated in the oil-water separator 421 is pressurized by a compressor and then transported to the gas pipeline network as fuel. This avoids the direct emission of light hydrocarbons, reduces pollution, and also reduces the consumption of natural gas and production costs.

[0045] Optionally, refer to Figure 2 The coal tar full-fraction hydrogenation system of this utility model also includes a bottom oil output device 7, a second-stage output device 8, and a storage device 9; the bottom oil output device 7 is connected to the bottom of the vacuum tower 3 and the storage device, and is used to output oil residue to the storage device 9; the second-stage output device 8 is connected to the vacuum tower 3 and the storage device 9, and is used to output wax oil components to the storage device 9.

[0046] Optionally, the heating device 2 in this utility model is a pressure reducing furnace.

[0047] In this embodiment, hydrogenated coal tar is added using a vacuum furnace to ensure uniform heating of the hydrogenated coal tar and prevent localized coking.

[0048] Optionally, a guide valve 43 is provided between the top oil output device 4 and the output pipeline 51 in this utility model, and the top oil output device 4 is also connected to the top oil storage unit 10.

[0049] In this embodiment, the mixing ratio of diesel and top-mounting oil can be adjusted (e.g., 0% to 100%) via the control valve 43 as needed, and a top-mounting oil storage unit 10 is provided to store unmixed top-mounting oil separately in a dedicated storage tank as a chemical raw material (e.g., solvent oil).

[0050] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0051] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A coal tar full fraction hydrogenation system capable of recycling reduced top oil, characterized by, The coal tar full-fraction hydrogenation system for recyclable top oil includes: a pretreatment unit (1), a heating device (2), a vacuum tower (3), a top oil output device (4), a first-line output device (5), and a tank farm unit (6). The pretreatment unit (1) is connected to the heating device (2) and is used to perform hydrogenation pretreatment on the coal tar to be treated to obtain hydrogenated coal tar. The heating device (2) is connected to the pressure reducing tower (3) and is used to heat the hydrogenated coal tar to above 370°C; A flow control valve (21) is provided between the pressure reducing tower (3) and the heating device (2) to ensure that the flow rate of hydrogenated coal tar entering the pressure reducing tower (3) is not higher than 50t / h; The pressure reducing oil output device (4) is connected to the top of the pressure reducing tower (3); The reduced pressure output device (5) is connected to the pressure reducing tower (3) and connected to the tank area unit (6) through the output pipeline (51) for outputting diesel components; The top oil output device (4) is connected to the output pipeline (51).

2. The coal tar full range hydroprocessing system for recyclable reduced top oil according to claim 1, characterized by, The reduced oil output device (4) includes a vacuum assembly (41) and a separation assembly (42); The vacuum assembly (41) is connected to the top of the pressure reducing tower (3) to make the pressure at the top of the pressure reducing tower (3) 2KPa to 14KPa and to extract the pressure reducing oil. The separation component (42) is connected to the vacuum component (41) and the output pipeline (51) to allow the top oil to be separated and mixed with the diesel components before entering the tank area unit (6).

3. The coal tar full range hydroprocessing system for recyclable reduced top oil according to claim 2, characterized by, The separation component (42) includes an oil-water separator (421) and a condensate pump (422). The oil-water separator (421) is connected to the vacuum assembly (41) and the oil-water separator (421) is connected to the output pipeline (51). The condensate pump (422) is connected to the oil-water separator (421) and also to the condensate circulation pipeline (401).

4. The coal tar full range hydroprocessing system for recyclable reduced top oil according to claim 3, characterized by, The separation component (42) further includes a non-condensable gas output component (423), which is connected to the oil-water separator (421) and the vacuum component (41), and is also connected to the gas pipeline network (402).

5. The coal tar full range hydroprocessing system for recyclable reduced top oil according to claim 1, wherein, The coal tar full-fraction hydrogenation system also includes a bottom oil output device (7), a second-stage output device (8), and a storage device (9); The reduced oil output device (7) is connected to the bottom of the pressure reducing tower (3) and the storage device (9) for outputting oil residue to the storage device (9); The reduced pressure output device (8) is connected to the pressure reducing tower (3) and the storage device (9) and is used to output wax oil components to the storage device (9).

6. The coal tar full range hydroprocessing system for recyclable reduced top oil of claim 1, wherein, The heating device (2) is a pressure reducing furnace.

7. The coal tar full range hydroprocessing system for recyclable reduced top oil according to claim 1, wherein, A guide valve (43) is provided between the top oil output device (4) and the output pipeline (51), and the top oil output device (4) is also connected to the top oil storage unit (10).

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