A raw material oil processing apparatus and a processing method

Abstract

The application relates to the technical field of heavy oil processing of petroleum, and discloses a raw material oil processing device and a processing method, which comprise a raw material pump, a water vapor supply mechanism, a coking heating furnace, a coke tower, a distillation tower, an oil outlet pump and a condenser; the raw material pump and the water vapor supply mechanism are communicated with the coking heating furnace through pipelines, the raw material pump inputs raw material oil into the coking heating furnace, the coke tower is provided with a gas phase area, a foam layer and a feeding area, the coking heating furnace is communicated with the feeding area through a pipeline, the bottom of the distillation tower is communicated with the gas phase area through a pipeline, the bottom end of the distillation tower is provided with a bottom oil outlet, the condenser is communicated with the top end of the distillation tower, the top end of the condenser is provided with a discharge port, the oil outlet pump is communicated with the middle part of the distillation tower and the gas phase area through pipelines respectively, and the oil outlet pump is used for conveying the quenching oil generated by the distillation tower to the foam layer; the heating temperature of the foam layer is 420-440 DEG C, the quenching oil conveyed by the oil outlet pump to the gas phase area accounts for 3-6% of the mass percentage of the raw material oil, and the generation of powder coke is effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heavy oil processing, in particular to a raw oil processing device and method. BACKGROUND

[0002] When the refinery uses inferior raw oil, propane deoiled pitch, catalytic cracking slurry containing catalyst powder, ethylene cracking tar or coal-based raw oil, through high-temperature cracking of the delayed coking device, coking gas, coking gasoline, coking diesel, coking wax oil and petroleum coke can be obtained, in addition, condensed oil by-products can be obtained in the cold coke process. Petroleum coke is an inevitable coking product in the high-temperature cracking process of inferior raw oil, and the structure of petroleum coke will be different according to the properties of the raw material and the operating conditions, which can be mainly divided into sponge block coke and powdery coke. A small amount of powdery coke is a common phenomenon in the process of delayed coking operation, but when a large amount of powdery coke appears, it will not only directly affect the quality grade of the coke product and even be unqualified, but also bring serious hidden dangers of production accidents, such as the shaking of the coke drum system equipment, the plugging of the fractionating tower tray and the plugging of the tower bottom oil heat exchanger, and even the plugging of the downstream coking gasoline and coking diesel hydrogenation reactor, in addition, it will also seriously pollute the environment.

[0003] With the development of comprehensive utilization and separation technology of catalytic cracking slurry oil, catalyst-containing very small clear slurry oil and catalyst powder-containing rich agent slurry oil (hereinafter referred to as rich agent slurry oil) will be obtained in the catalyst removal and separation of catalytic cracking slurry oil. Most of the rich agent slurry oil is mixed into the feed oil of the delayed coking device for processing, thereby increasing the yield of high value-added liquid oil and reducing the amount of solid waste in the refinery. After the delayed coking device is mixed with the rich agent slurry oil, the catalytic cracking catalyst powder contained in the feed oil still has a certain catalytic cracking activity, and the feed oil is heated to 485-505℃ by the coking furnace, which can accelerate the cracking reaction of coke, causing the foam layer in the coking tower to increase in foam and thickness, and the sponge block coke is carried in the gas stream to generate powder coke. At present, in order to produce safety and avoid the appearance of powder coke, most companies adopt the following methods to reduce powder coke: reducing the amount of mixed catalytic slurry oil, especially rich agent slurry oil, controlling the catalyst content in the coking feed oil; reducing the furnace outlet temperature; increasing the top pressure of the coking tower; injecting high-value organic silicon defoaming agent. Although this can reduce the appearance of powder coke, the negative effects are the decrease of the target product liquid oil yield, the increase of energy consumption, the decrease of processing capacity, the increase of silicon content in the oil product, which is not conducive to downstream processing and increases the operating cost, and directly leads to a significant decrease in economic benefit. Through research, it is found that there are two main reasons for the generation of powder coke from poor quality feed oil: one is the poor physicochemical properties of the feed oil, especially the presence of a large amount of catalyst powder and surfactant foam-prone feed oil, which is the internal cause of the generation of powder coke from poor quality feed oil; the second is the harsh operation condition of coke formation, especially the low reaction pressure taken to improve the conversion rate and obtain a high liquid oil yield, which leads to the generation of a large amount of fine foam and powder coke due to the excessive agitation of the foam layer by the oil gas in the coking tower, which is the external cause of the generation of powder coke from poor quality feed oil. SUMMARY

[0004] The technical problem to be solved by the present application is that the existing method for reducing powder coke in feed oil processing is low in efficiency, high in energy consumption and cost.

[0005] In order to solve the above technical problems, the application provides a raw oil processing device, which comprises a raw material pump, a water vapor supply mechanism, a coking heating furnace, a coke tower, a distillation tower, an oil outlet pump and a condenser; the raw material pump and the water vapor supply mechanism are connected with the coking heating furnace through pipelines, the raw material pump inputs raw oil into the coking heating furnace, the coke tower is sequentially provided with a gas phase zone, a foam layer and a feeding zone from top to bottom, the coking heating furnace is connected with the feeding zone through a pipeline, the bottom of the distillation tower is connected with the gas phase zone through a pipeline, the bottom end of the distillation tower is provided with a bottom oil outlet, the condenser is connected with the top end of the distillation tower, the top end of the condenser is provided with an outlet, the oil outlet pump is connected with the middle part of the distillation tower and the gas phase zone through pipelines respectively, and the oil outlet pump is used for conveying quenching oil generated by the distillation tower to the foam layer; the heating temperature of the foam layer is 420-440 DEG C, and the quenching oil conveyed by the oil outlet pump to the gas phase zone accounts for 3-6% of the mass percentage of the raw oil.

[0006] Further, a circulating pump is further included, and the circulating pump is connected with the bottom end of the distillation tower and the raw material pump through pipelines respectively.

[0007] Further, the coke tower is provided with a plurality of temperature measuring points from top to bottom, and the temperature measuring points are used for detecting the temperature in the coke tower.

[0008] Further, the coke tower is provided with a plurality of material level meters from top to bottom, and the material level meters are used for detecting the material level in the coke tower.

[0009] Further, the water vapor supply mechanism comprises a water supply pump and a water vapor heater, and the water vapor heater is connected with the water supply pump and the coking heating furnace through pipelines respectively.

[0010] Further, an adjusting valve is arranged between the coke tower and the distillation tower, the adjusting valve is connected with the coke tower and the oil outlet pump through pipelines respectively, and the oil outlet pump is further connected with an oil discharge pipe.

[0011] A raw oil processing method, which comprises the following steps:

[0012] S01, raw oil is mixed with water vapor after being pressurized;

[0013] S02, the raw oil is conveyed to a coking heating furnace for heating;

[0014] S03, the raw oil is conveyed into a coke tower for coking, the temperature of the foam layer is controlled to be 420-440 DEG C, and coking oil gas generated by the coke tower is conveyed to a distillation tower for fractionation;

[0015] S04, the distillation column fractionates the coking oil into wax oil and coking diesel, part of the wax oil is discharged from the bottom oil outlet, part of the coking diesel and part of the wax oil are sent to the coke tower as quenching oil through the oil outlet pump, and part of the coking diesel and part of the wax oil are discharged after being cooled by the condenser, wherein the quenching oil sent to the coke tower accounts for 3-6% of the mass percentage of the raw oil.

[0016] Further, in step S04, the wax oil discharged from the bottom oil outlet is mixed with water vapor after being pressurized and then is sent to the coking heating furnace.

[0017] Further, in step S02, the heating temperature of the coking heating furnace is 495-505℃.

[0018] Compared with the prior art, the raw oil processing device and method has the beneficial effects that the heating temperature of the foam layer is controlled to be 420-440℃, the quenching oil sent to the gas phase zone by the oil outlet pump accounts for 3-6% of the mass percentage of the raw oil, the foam layer is appropriately cooled by introducing an appropriate amount of quenching oil into the foam layer, the generation amount of foam in the foam layer is controlled, the risk of powder coke is reduced, and the temperature of the foam layer is controlled to be 420-440℃, which can effectively inhibit the generation of powder coke. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic diagram of an embodiment of the present application;

[0020] Figure 2 is a structural schematic diagram of a coke tower in an embodiment of the present application.

[0021] In the figure, 1 is a raw material pump; 2 is a water vapor supply mechanism; 21 is a water supply pump; 22 is a water vapor heater; 3 is a coking heating furnace; 4 is a coke tower; 41 is a gas phase zone; 42 is a foam layer; 43 is a feeding zone; 431 is coke; 432 is a feeding channel; 44 is a temperature measuring point; 45 is a material level meter; 5 is a distillation tower; 51 is an oil outlet pump; 52 is a regulating valve; 6 is a condenser; and 7 is a circulating pump. DETAILED DESCRIPTION

[0022] The specific embodiments of the present application will be further described in detail below in combination with the drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0023] In the description of the present application, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back", "top" and "bottom" in the present application are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0024] As Figure 1 A raw oil processing device of a preferred embodiment of the present application is shown in Fig. 2, which comprises a raw oil pump 1, a water vapor supply mechanism 2, a coking heating furnace 3, a coke 431 tower 4, a distillation tower 5, an oil outlet pump 51 and a condenser 6.

[0025] The raw oil pump 1 can be externally connected to a pipeline for conveying raw oil. The raw oil pump 1 and the coking heating furnace 3 are connected by a pipeline. The raw oil is input into the coking heating furnace 3 under the action of the raw oil pump 1 after being pressurized. The raw oil can be a cracking and foaming raw oil. The raw oil is mixed with a rich oil slurry containing high-concentration catalyst powder, which accounts for more than 15% of the mass percentage of the raw oil.

[0026] The water vapor supply mechanism 2 is connected to the coking heating furnace 3 by a pipeline. The water vapor supply mechanism inputs water vapor into the coking heating furnace 3. The water vapor mixes with the raw oil after entering the coking heating furnace 3. The coking heating furnace 3 can heat the raw oil mixed with water vapor.

[0027] The coke 431 tower 4 is sequentially provided with a gas phase zone 41, a foam layer 42 and a feeding zone 43 from top to bottom. The feeding zone 43 comprises a ring-shaped coke 431 and a feeding passage 432 located at the center of the coke 431. The foam layer 42 comprises a gas phase foam layer 42 and an oil phase foam layer 42. The gas phase foam layer 42 is located above the oil phase foam layer 42. The coking heating furnace 3 is connected to the feeding zone 43 by a pipeline. The coking heating furnace 3 heats the raw oil mixed with water vapor to 500±5℃, and then inputs the raw oil at about 500℃ into the coke 431 tower 4. The heating temperature of the foam layer 42 is 420-440℃. The coke 431 tower 4 is provided with a heat preservation device. The heat preservation device can preserve the temperature of the raw oil in the coke 431 tower 4, so that the temperature of the foam layer 42 is controlled at 420-440℃. The pressure of the gas phase zone 41 is generally controlled at about 0.13Mpa. When it is necessary to observe and analyze the type of petroleum coke generated in the coke 431 tower 4, water vapor can be input into the coke 431 tower 4 after stopping the conveying of raw oil into the coke 431 tower 4. The water vapor is used to strip the oil gas in the coke 431 for 4 hours. When the coke 431 tower 4 is cooled to near room temperature, the upper and lower cover plates of the coke 431 tower 4 are opened. The petroleum coke is observed and detected by naked eyes to be blocky coke or powdery coke.

[0028] The bottom of the distillation column 5 is connected with the gas phase zone 41 through a pipeline, and the coking oil gas generated in the coke 431 column 4 can enter the distillation column 5 for fractionation from the gas phase zone 41. The bottom end of the distillation column 5 is provided with a bottom oil outlet, and part of the wax oil fractionated from the distillation column 5 is outputted outwards through the bottom oil outlet. The oil outlet pump 51 is connected with the middle part of the distillation column 5 and the gas phase zone 41 through pipelines respectively, and part of the wax oil and diesel oil fractionated from the distillation column 5 are used as quenching oil, which is driven by the oil outlet pump 51 to pass through the gas phase zone 41 and then reaches the foam layer 42, wherein the quenching oil sent to the gas phase zone 41 by the oil outlet pump 51 accounts for 3-6% of the mass percentage of the raw oil. When the foam layer 42 is lower after the raw oil is initially fed into the coke 431 column 4, a small amount of quenching oil of about 3% can be injected, and a higher temperature of the foam layer 42 is maintained, so as to improve the coking reaction of the coke 431; when the foam layer 42 is higher after the raw oil is fed into the coke 431 column 4 in the later period, quenching oil of about 6% can be injected, and a lower temperature of the foam layer 42 is controlled, so as to reduce the amount of foam generated and the amount of oil gas carrying foam out of the coke 431 column 4 and into the fractionation column, in addition, reducing the temperature of the foam layer 42 can also effectively reduce the linear velocity of the oil gas in the coke 431 column 4, so as to prevent the oil gas from carrying the foamed coke powder out of the coke 431 column 4 and into the fractionation column. The condenser 6 is connected with the top end of the distillation column 5, and the top end of the condenser 6 is provided with a discharge port, and part of the coking oil gas is cooled by the condenser 6 after being fractionated by the distillation column 5, so as to form sewage, coking gas, coking gasoline and the like which are discharged from the discharge port. The quenching oil is injected into the gas phase zone 41 in a liquid phase state, and is injected into the lower part of the coke 431 column 4 and directly reaches the foam layer 42 in the coke 431 column 4, and the flowing direction of the quenching oil is opposite to that of the coking gas flow in the coke 431 column 4. By spraying the quenching oil to the foam layer 42, the temperature of the gas phase foam is reduced, so as to reduce the amount of foam generated.

[0029] The raw oil processing device further comprises a circulating pump 7, which is connected with the bottom end of the distillation column 5 and the oil outlet pump 51 through pipelines respectively. Part of the wax oil fractionated from the distillation column 5 is outputted outwards through the bottom oil outlet, and then is fed to the inlet of the raw oil pump 1 through the circulating pump 7, mixed with the raw oil at the inlet of the raw oil pump 1, and then is fed to the coking heater 3 through the raw oil pump 1 again, so as to form the wax oil generated by the circulation and shunt.

[0030] The coke 431 column 4 is provided with a plurality of temperature measuring points 44 from top to bottom, which are used for detecting the temperature in the coke 431 column 4, so as to facilitate the staff to understand the temperature of each part of the coke 431 column 4. The coke 431 column 4 is provided with a plurality of material level meters 45 from top to bottom, which are used for detecting the material level in the coke 431 column 4, so as to facilitate the staff to understand the petroleum coke content of each part in the coke 431 column 4.

[0031] The water vapor supply mechanism 2 comprises a water supply pump 21 and a water vapor heater 22, the water vapor heater 22 is communicated with the water supply pump 21 and the coking heating furnace 3 through pipes respectively, the water supply pump 21 can be provided with a water supply pipe, the water supply pump 21 is used for conveying softened water to the water vapor heater 22, and the water vapor heater 22 is used for heating the softened water into water vapor.

[0032] The coke 431 tower 4 and the distillation tower 5 are provided with an adjusting valve 52, the adjusting valve 52 is communicated with the coke 431 tower 4 and the oil outlet pump 51 through pipes respectively, the oil outlet pump 51 is also connected with an oil discharge pipe, and the adjusting valve 52 is arranged, so that the staff can adjust the amount of quenching oil input into the coke 431 tower 4, and the excess quenching oil generated by the distillation tower 5 can be discharged through the oil discharge pipe.

[0033] A raw material oil processing method, comprising the following steps:

[0034] S01, the raw material oil is extracted by using a raw material pump 1, the raw material oil is conveyed to the coking heating furnace 3 after being pressurized, at the same time, the water vapor supply mechanism 2 conveys water vapor to the coking heating furnace 3, and the raw material oil is mixed with the water vapor in the coking heating furnace 3.

[0035] S02, the raw material oil mixed with water vapor is conveyed to the coking heating furnace 3 for heating, and the raw material oil is heated to 500±5 DEG C.

[0036] S03, the heated raw material oil is conveyed to the coke 431 tower 4 for coking, the temperature of the foam layer 42 is controlled to be 420-440 DEG C, and the coking oil gas generated by the coke 431 tower 4 is conveyed to the distillation tower 5 for fractionation.

[0037] S04, the coking oil is fractionated into wax oil and coking diesel by the distillation tower 5, part of the wax oil is discharged from the bottom oil outlet, the wax oil discharged from the bottom oil outlet is mixed with water vapor again after being pressurized, and then is conveyed to the coking heating furnace 3 again; part of the coking diesel and part of the wax oil are conveyed to the coke 431 tower 4 as quenching oil through the oil outlet pump 51, and part of the coking diesel and part of the wax oil are cooled and discharged through the condenser 6, wherein the quenching oil input into the coke 431 tower 4 accounts for 3-6% of the mass percentage of the raw material oil; the temperatures of the foam layers 42 at different heights in the coke 431 tower 4 are observed through the temperature measuring points 44 and the material level meters 45, and the amount of the quenching oil entering the top of the coke 431 tower 4 is controlled through the adjusting valve 52, so that the temperatures of the foam layers 42 at different heights are controlled to be between 420 DEG C and 440 DEG C, thereby making the coke 431 tower 4 generate blocky coke as much as possible and not generate powdery coke as much as possible.

[0038] Different raw material oil samples are tested by using the raw material oil processing device and the processing method, the test results are compared with the results obtained by using the traditional method for processing different raw material oil samples, and the specific experimental results are as follows:

[0039] Table 1

[0040]

[0041]

[0042]

[0043] Wherein the delay coking device type is pilot indicates that the processing device and processing method of raw oil sample are tested by using the raw oil described in the application, and the delay coking device type is industrial indicates that the raw oil sample is tested by using the traditional process method.

[0044] From Table 1, it can be seen that:

[0045] In the prior art, when the conventional method is used to treat the inferior raw oil which is prone to generate powder coke and is mixed with rich agent oil slurry, in order to avoid the generation of powder coke, the following measures are taken: reducing the reaction temperature at the furnace outlet, increasing the reaction pressure at the top of the tower, and increasing the circulation ratio. Although these measures can inhibit the generation of powder coke to some extent, powder coke still appears. When the pilot device is used to treat the inferior raw oil which is prone to generate powder coke and is mixed with rich agent oil slurry, harsh operating conditions of high temperature, low pressure and low circulation ratio are adopted. However, due to the control of the temperature of the foam layer 42 in the coke 431 tower 4, the amount of generated foam is reduced, and the oil content in the low-temperature foam is prone to settle back into the liquid phase to form coke, so that the amount of generated powder coke is greatly reduced. These results show that no matter how poor the properties of the raw oil are and how harsh the operating conditions are, as long as 3%-6% (mass ratio) of the quenching oil is injected into the coke 431 tower 4 and the temperature of the foam layer 42 in the coke 431 tower 4 is controlled to be 420-440℃, the amount of generated powder coke can be effectively controlled.

[0046] In summary, the embodiment of the application provides a processing device and processing method of raw oil, which controls the heating temperature of the foam layer 42 to be 420-440℃ and controls the mass percentage of the quenching oil in the raw oil to be 3-6% which is transported to the gas phase zone 41 by the oil outlet pump 51. By injecting an appropriate amount of quenching oil into the foam layer 42, the foam layer 42 is appropriately cooled and the amount of generated foam in the foam layer 42 is controlled, thereby reducing the risk of powder coke. In addition, controlling the temperature of the foam layer 42 to be 420-440℃ can effectively inhibit the generation of powder coke.

[0047] The above only describes the preferred embodiments of the application, and it should be noted that for those skilled in the art, without departing from the technical principles of the application, a number of improvements and substitutions can be made, and these improvements and substitutions should also be considered as the protection scope of the application.

Claims

1. A method for processing a feed oil, characterized by, The device for processing raw oil used in the method comprises a raw oil pump, a water vapor supply mechanism, a coking heating furnace, a coke tower, a distillation tower, an oil outlet pump and a condenser; The raw oil pump and the water vapor supply mechanism are connected to the coking heating furnace through pipelines, the raw oil pump inputs raw oil into the coking heating furnace, the coke tower is sequentially provided with a gas phase zone, a foam layer and a feeding zone from top to bottom, the coking heating furnace is connected to the feeding zone through a pipeline, the bottom of the distillation tower is connected to the gas phase zone through a pipeline, the bottom end of the distillation tower is provided with a bottom oil outlet, the condenser is connected to the top end of the distillation tower, the top end of the condenser is provided with a discharge port, the oil outlet pump is connected to the middle part of the distillation tower and the gas phase zone through pipelines respectively, and the oil outlet pump is used to output the quenching oil generated by the distillation tower to the foam layer; The heating temperature of the foam layer is 420-440℃, the quenching oil output by the oil outlet pump to the gas phase zone accounts for 3-6% of the mass percentage of the raw oil, the coke tower is provided with multiple temperature measuring points from top to bottom, the temperature measuring points are used to detect the temperature in the coke tower, the coke tower is provided with multiple material level meters from top to bottom, the material level meters are used to detect the material level in the coke tower, the temperature measuring points and the material level meters are matched to observe the temperature of the foam layer at each height in the coke tower, the amount of the quenching oil entering the coke tower can be controlled to control the temperature of the foam layer to be between 420-440℃, so as to inhibit the generation of powder coke; The processing method comprises the following steps: S01, mixing the raw oil with water vapor after pressurization; S02, inputting the raw oil to the coking heating furnace for heating; S03, inputting the raw oil into the coke tower for coking, controlling the temperature of the foam layer to be 420-440℃, and outputting the coking oil gas generated by the coke tower to the distillation tower for fractionation; S04, fractionating the coking oil into wax oil and coking diesel in the distillation tower, discharging part of the wax oil from the bottom oil outlet, outputting part of the coking diesel and part of the wax oil as quenching oil to the coke tower through the oil outlet pump, and discharging part of the coking diesel and part of the wax oil after cooling in the condenser, wherein the quenching oil input into the coke tower accounts for 3-6% of the mass percentage of the raw oil.

2. The method of processing a feed oil according to claim 1, characterized in that: A circulating pump is further included, which is connected to the bottom end of the distillation tower and the raw oil pump through pipelines.

3. The method of processing a feed oil according to claim 1, characterized in that: The water vapor supply mechanism comprises a water supply pump and a water vapor heater, and the water vapor heater is connected to the water supply pump and the coking heating furnace through pipelines.

4. The method of processing a feed oil according to claim 1, characterized in that: An adjusting valve is arranged between the coke tower and the distillation tower, the adjusting valve is connected to the coke tower and the oil outlet pump through pipelines, and the oil outlet pump is further connected with an oil discharge pipe.

5. The method of processing a feed oil according to claim 1, characterized in that: In step S04, the wax oil discharged from the bottom oil outlet is mixed with water vapor after pressurization and then input into the coking heating furnace.

6. The method of processing a feed oil according to claim 1, characterized in that: In step S02, the heating temperature of the coking heating furnace is 495-505℃.

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