Fluidized bed residual oil hydrocracking feeding system
By introducing high-aromatic oil into the feedstock of fluidized bed residue hydrocracking, the coking problem caused by asphaltenes precipitation in residue products was solved, thereby improving residue conversion rate and extending unit operating cycle, resulting in increased economic benefits.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-26
- Publication Date
- 2026-03-17
AI Technical Summary
Existing fluidized bed residue hydrocracking technology causes asphaltenes to precipitate from unconverted residue products during the reaction process, leading to coking of the equipment and limiting residue conversion rate and unit operating cycle.
By introducing high-aromatic oil, especially catalytic slurry, into the feedstock for slag reduction, and using mixing shear pumps and pipeline equipment for mixing, asphalt deposits are reduced and the operating cycle of the unit is extended.
It effectively reduces asphalt deposits in the unit, improves the conversion rate of residual oil, extends the operating cycle of the unit, and enhances economic benefits.
Smart Images
Figure CN223996026U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of chemical production technology, specifically to a fluidized bed residue oil hydrocracking feed system. Background Technology
[0002] Petroleum resources are non-renewable and are currently the primary source of energy and chemical raw materials for human survival. As petroleum resources become increasingly scarce, the proportion of heavy crude oil processed will increase significantly, making the selection of heavy oil processing solutions crucial. Eluented bed residue hydrocracking technology, with its advantages of high residue conversion rate, low environmental pollution, and high return on investment, is widely adopted. However, during the reaction process, eluented bed residue hydrocracking technology disrupts the stability of the residue feedstock, leading to the easy precipitation of asphaltenes in the unconverted residue product. This, in turn, causes coking in subsequent equipment and pipelines, limiting the residue conversion rate of all residue hydrocracking units, impacting the overall plant's economic benefits, or shortening the unit's operating cycle. Therefore, controlling the relationship between the stability of unconverted residue and the residue conversion rate in eluented bed residue hydrocracking units is key to ensuring the safe, stable, long-term, full-capacity, and high-quality operation of the unit.
[0003] Currently, some companies began researching technologies to improve conversion rates and reduce coking in fluidized bed residue hydrocracking units many years ago. They mainly conducted a series of studies on unit conversion rates, feedstock properties, catalysts, catalyst additives, and equipment structure. The research results have been widely applied in industrial units, achieving the effects of improving unit conversion rates and slowing down coking. Utility Model Content
[0004] In view of the deficiencies of the prior art, this utility model provides a fluidized bed residue hydrocracking feed system, which can reduce asphaltene deposition in the unit and extend the unit's operating cycle by introducing a certain proportion of high aromatic oil into the residue feedstock.
[0005] To achieve the above objectives, the present invention provides a fluidized bed residue hydrocracking feed system, comprising a vacuum residue feed pipeline, a feed buffer tank, a high aromatic oil storage tank, a mixing shear pump, and a vacuum residue mixing pipeline. The feed inlet of the feed buffer tank is connected to the vacuum residue feed pipeline, and the feed outlet of the feed buffer tank is connected to the feed booster pump. The high aromatic oil storage tank is connected to a high aromatic oil steam heater. The inlet of the mixing shear pump is connected to the high aromatic oil steam heater via the high aromatic oil mixing pipeline, and the outlet of the mixing shear pump is connected to the feed inlet of the feed buffer tank. The vacuum residue mixing pipeline extends from the vacuum residue feed pipeline to the inlet of the mixing shear pump, and a first valve is installed on the vacuum residue mixing pipeline.
[0006] Furthermore, the outlet of the mixing shear pump is connected to the inlet of the raw material buffer tank via a mixing pipeline.
[0007] Furthermore, a second valve is installed on the vacuum residue inlet pipeline downstream of the junction point between the vacuum residue mixing pipeline and the vacuum residue inlet pipeline.
[0008] Furthermore, the high aromatic oil storage tank is connected to the high aromatic oil steam heater via a high aromatic oil feed pipeline, and a filter and a high aromatic oil pump are sequentially installed along the feed direction on the high aromatic oil feed pipeline.
[0009] Furthermore, the filter is a basket filter.
[0010] Furthermore, the high aromatic oil steam heater is a U-tube heat exchanger.
[0011] The beneficial effects of this utility model are: by setting up pipelines and devices to introduce a certain proportion of high aromatic oil into the slag reduction feedstock, it is possible to reduce the asphalt deposition in the device and extend the operating cycle of the device. Attached Figure Description
[0012] Figure 1 This is a process flow diagram of a fluidized bed residue hydrocracking feed system in one embodiment of the present invention.
[0013] In the picture:
[0014] 100. Pressure-reducing residue feed pipeline; 110. Second valve;
[0015] 200. Raw material buffer tank; 210. Raw material booster pump.
[0016] 300. High-aromatic oil storage tank; 310. High-aromatic oil feed pipeline; 311. Filter; 312. High-aromatic oil pump; 320. High-aromatic oil steam heater.
[0017] 400. Mixing shear pump; 410. High aromatic oil mixing line; 420. Mixing line.
[0018] 500, depressurized residue mixing pipeline; 510, first valve. Detailed Implementation
[0019] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.
[0020] The feedstock for fluidized bed residue hydrocracking is typically vacuum residue from an atmospheric and vacuum distillation unit. Vacuum residue is a four-component system consisting of saturated fractions, aromatic fractions, gums, and asphaltenes. The instability index of this system is calculated as (saturated fractions + asphaltenes) / (aromatic fractions + gums). A higher instability index indicates a greater likelihood of coking. Fluidized bed residue hydrocracking offers higher conversion rates than fixed bed hydrocracking. However, as the conversion rate increases, the aromatic fractions become hydrogenated and saturate, leading to a decrease in aromaticity within the system. Asphaltenes become saturated and precipitate, becoming precursors to coking and impacting operational stability.
[0021] See Figure 1 This diagram illustrates a process flow chart of a fluidized bed residue hydrocracking feed system according to an embodiment of the present invention. The system includes a vacuum residue feed pipeline 100, a feed buffer tank 200, a high-aromatic oil storage tank 300, a mixing shear pump 400, and a vacuum residue mixing pipeline 500. The inlet of the feed buffer tank 200 is connected to the vacuum residue feed pipeline 100, and the outlet of the feed buffer tank 200 is connected to the feed booster pump 210. The high-aromatic oil storage tank 300 is connected to a high-aromatic oil steam heater 310. The inlet of the mixing shear pump 400 is connected to the high-aromatic oil steam heater 310 via the high-aromatic oil mixing pipeline 410, and the outlet of the mixing shear pump 400 is connected to the inlet of the feed buffer tank 200. The vacuum residue mixing pipeline 500 is led out from the vacuum residue feed pipeline 100 to the inlet of the mixing shear pump 400, and a first valve 510 is installed on the vacuum residue mixing pipeline 500.
[0022] The aforementioned fluidized bed residue hydrocracking feed system introduces high-aromatic oil into the residue feedstock through pipelines and equipment. By introducing a certain proportion of high-aromatic oil into the residue feedstock, asphaltene deposition in the unit can be reduced, and the operating cycle of the unit can be extended.
[0023] In a preferred technical solution, the high aromatic oil is derived from the tail oil of catalytic cracking, i.e., catalytic slurry.
[0024] In one embodiment, the outlet of the mixing shear pump 400 is connected to the inlet of the raw material buffer tank 200 via a mixing line 420.
[0025] In one embodiment, a second valve 110 is installed on the vacuum residue feed line 100 downstream of the junction point between the vacuum residue mixing line 500 and the vacuum residue feed line 100. During process switching, the second valve 110 is closed, and the first valve 510 is opened. Vacuum residue enters the mixing shear pump 400 from the vacuum residue mixing line 500, and high-aromatic oil enters the mixing shear pump 400 from the high-aromatic oil mixing line 410. After thorough mixing, the two streams pass through the mixing line 420 into the feedstock buffer tank 200, providing feedstock for the downstream fluidized bed residue hydrocracking reactor.
[0026] In one embodiment, the high aromatic oil storage tank 300 is connected to the high aromatic oil steam heater 320 via a high aromatic oil feed pipeline 310. A filter 311 and a high aromatic oil pump 312 are sequentially arranged on the high aromatic oil feed pipeline 310 along the feed direction.
[0027] In one embodiment, filter 311 is a basket filter. In this embodiment, a basket filter is used to filter the catalytic slurry in the high aromatic oil storage tank 300 to prevent unnecessary impurities from entering the mixing shear pump 400 and affecting subsequent production. In this embodiment, the mixing shear pump 400 is a shear pump manufactured by SIL VERSON.
[0028] Specifically, the aforementioned fluidized bed residue hydrocracking feed system introduces 5% of the high aromatic oil (catalytic slurry) into the vacuum residue feedstock via the high aromatic oil storage tank 300. It should be noted that, through experiments to adjust the proportion of the catalytic slurry, and subsequent analysis of the asphaltene conversion rate and coking conditions, it was found that a 5% proportion significantly alleviates asphaltene and coking issues, while also reducing the amount of vacuum residue feedstock. Further, the catalytic slurry is heated to 170°C using a high aromatic oil steam heater 310. Inside the mixing shear pump 400, it is mixed with the vacuum residue feedstock introduced from the vacuum residue mixing pipeline 500. After thorough mixing, the mixture enters the feedstock buffer tank 200, and from there, it is pressurized by the feedstock booster pump 210 before entering the hot feedstock buffer tank (not shown in the figure) for fluidized bed residue hydrocracking. In one embodiment, the high-aromatic oil steam heater 310 uses a U-tube heat exchanger manufactured by Sichuan Kexin Electromechanical Technology Co., Ltd., and the heat exchange medium is 1.0 MPa steam at 210°C. Typically, the sediment content of the oil in the unit is controlled at around 0.2 wt%, making the unit's operation relatively economical. Without the introduction of high-aromatic oil, the sediment content is 0.22 wt% with a residue oil conversion rate of 67%, while with the introduction of high-aromatic oil, the sediment content is still 0.22 wt% with a residue oil conversion rate of 70%, representing a 3 percentage point improvement. Based on a unit feed rate of 380 t / h, and a price difference of 600 yuan per ton between unconverted oil and light oil, a profit of 57 million yuan per year can be achieved. In other words, while maintaining the unit's conversion rate, the feeding method of this invention can reduce the total sediment in the unit.
[0029] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0031] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature. It should be noted that when an element is referred to as "fixed to" or "set on" another element, it can be directly on the other element or there may be an intermediate element present. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element present. The terms "vertical," "horizontal," "above," "below," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible embodiments.
Claims
1. An ebullated bed residue hydrocracking feed system characterized by: Comprising a vacuum residue feed line; a feedstock buffer tank, a feed inlet of which is connected to the vacuum residue feed line, and a feed outlet of which is connected to a feedstock booster pump; a high aromatic oil storage tank, which is connected to a high aromatic oil steam heater; a mixing shear pump, an inlet of which is connected to the high aromatic oil steam heater through a high aromatic oil mixing line, and an outlet of which is connected to the feed inlet of the feedstock buffer tank; a vacuum residue mixing line, which is led out from the vacuum residue feed line to the inlet of the mixing shear pump, and on which a first valve is arranged.
2. An ebullated bed residue hydrocracking feed system according to claim 1, characterized in that: The outlet of the mixing shear pump is connected to the feed inlet of the feedstock buffer tank through a mixing line.
3. An ebullated bed residuum hydrocracking feed system according to claim 2 characterized by: A second valve is arranged on the vacuum residue feed line downstream of the junction point of the vacuum residue mixing line and the vacuum residue feed line.
4. An ebullated bed residuum hydrocracking feed system according to any one of claims 1-3, characterized by: The high aromatic oil storage tank is connected to the high aromatic oil steam heater through a high aromatic oil feed line, and a filter and a high aromatic oil oil pump are arranged in sequence along the feed direction on the high aromatic oil feed line.
5. An ebullated bed residuum hydrocracking feed system according to claim 4 characterized by: The filter is a basket filter.
6. An ebullated bed residuum hydrocracking feed system according to any one of claims 1-3, characterized by: The high aromatic oil steam heater is a U-tube heat exchanger.