A kind of styrene tar processing device and method

Abstract

The invention discloses a styrene tar processing device and a method thereof. A main conveying pipeline is extended after a petroleum slurry pipeline and a vacuum residue oil pipeline are gathered. The styrene tar pipeline is connected to the main conveying pipeline, and the main conveying pipeline is connected to a raw material tank. The outlet of the raw material tank is connected to a raw material pump through a pipeline, and the raw material pump is connected to a heating furnace through a pipeline. The heating furnace is connected to a coke tower through a pipeline. The styrene tar pipeline is purged, airtight and replaced to meet the requirements. The styrene tar pipeline is connected to an external styrene device or a tank area to supply styrene tar, and the pressure in the styrene tar pipeline is controlled to be higher than the pressure in the raw material tank. The valve on the styrene tar pipeline is slowly opened. The mixed raw materials are extracted by the raw material pump, heat-exchanged to 280°C by a heat exchanger, enter the heating furnace, and are heated to 500°C before being sent to a coke tower for cracking and condensation reactions. The oil and gas after the reaction in the coke tower enter a fractionation tower to fractionate naphtha, diesel and wax oil fractions, and coke is generated in the coke tower.

Description

Technical Field

[0001] The present invention relates to a processing device and a method thereof, and more specifically, to a processing device and a method thereof for styrene tar, and belongs to the field of petrochemical industry. Background Art

[0002] Styrene is an organic compound formed by replacing a hydrogen atom on ethylene with benzene. 6 H 5 CH=CH 2 It is insoluble in water, soluble in ethanol and ether, and gradually polymerizes and oxidizes when exposed to air. It is an important monomer for industrial synthetic resins, ion exchange resins, and synthetic rubber. As of 2019, the global styrene production capacity is 35 million tons, of which China's production capacity accounts for 27% of the global production capacity.

[0003] The complete set of styrene technologies mainly include ethylbenzene catalytic dehydrogenation, propylene oxide-styrene co-production, pyrolysis gasoline extraction, butadiene synthesis, etc. More than 90% of domestic companies use ethylbenzene catalytic dehydrogenation, such as the most commonly used Badger process. The styrene distillation system adopts multi-effect evaporation distillation technology. The styrene tower is divided into two towers by a single tower. Differential pressure thermal coupling distillation is adopted. The condenser of the high-pressure tower can be used as the reboiler of the low-pressure tower. Compared with the single styrene distillation tower of the traditional styrene device, the energy consumption is reduced by 50%. In addition, its pressure drop is small, which reduces the generation of tar (the yield can be reduced to about 1.67%).

[0004] The traditional treatment method of styrene tar can only recover the residual styrene, inhibitors and other components in styrene tar, and the remaining waste cannot be treated; or it can be handed over to a professional hazardous waste treatment company for treatment, with a processing fee of about 2,000 yuan / ton. Based on a 600,000 tons / year styrene unit and a tar output of 10,000 tons, the annual treatment cost is as high as 20 million yuan. Therefore, it is more appropriate to continue to refining this material, but there is a lack of a device and method that can save huge treatment costs and convert it into coking diesel, wax oil, petroleum coke and other products with higher added value. Summary of the invention

[0005] In order to solve the above-mentioned prior art problems, the present invention provides a styrene tar processing device and method which has the technical characteristics of not only saving huge processing costs but also being able to convert it into coking diesel, wax oil, petroleum coke and other products with high added value.

[0006] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0007] A styrene tar processing device comprises a catalytic oil slurry pipeline, a vacuum residue oil pipeline and a styrene tar pipeline, wherein the catalytic oil slurry pipeline and the vacuum residue oil pipeline are combined to form a main conveying pipeline, the styrene tar pipeline is connected to the main conveying pipeline, the main conveying pipeline is connected to a raw material tank, the raw material tank outlet is connected to a raw material pump via a pipeline, the raw material pump is connected to a heating furnace via a pipeline, and the heating furnace is connected to a coke tower via a pipeline.

[0008] As a preference, the catalytic oil slurry pipeline, the vacuum residue oil pipeline and the styrene tar pipeline are all connected with valves.

[0009] As a preferred embodiment, the main conveying pipeline, the raw material pump and the heating furnace pipeline are all connected with a heat exchanger.

[0010] As a preferred embodiment, two valves are provided on the catalytic oil slurry pipeline.

[0011] As a preferred embodiment, two heat exchangers are connected to the raw material pump and the heating furnace pipeline.

[0012] A method for processing styrene tar, characterized in that the method comprises the following steps:

[0013] 1) Confirm that the processing device is running smoothly, and the styrene tar pipeline 3 is purged, airtight, and replaced to ensure that there is no residual moisture in the styrene tar pipeline;

[0014] 2) connecting a styrene tar pipeline to an external styrene device or tank farm to supply styrene tar, and controlling the pressure in the styrene tar pipeline to be higher than the pressure in the raw material tank;

[0015] 3) Slowly open the valve on the styrene tar pipeline to control the flow rate of tar to less than 1% of the total feed flow rate;

[0016] 4) The mixed raw materials are pumped out by the raw material pump, heat exchanged to 280℃ by the heat exchanger and then enter the heating furnace. After being heated to 500℃, they are sent to the coke tower for cracking and condensation reactions. The oil and gas after the reaction in the coke tower enter the distillation tower to distill out naphtha, diesel and wax oil fractions, and coke is generated in the coke tower.

[0017] As a preference, in step 2), the valves in the catalytic oil slurry pipeline and the vacuum residue oil pipeline are both in an open state.

[0018] Beneficial effects:

[0019] 1. The processing technology and process are simple, which realizes the harmless processing of styrene tar and avoids environmental pollution.

[0020] 2. After being processed by this processing method, styrene tar can be easily converted into coking diesel, wax oil, petroleum coke and other products, which has great economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the process structure of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings, but the present invention is not limited to the following embodiments.

[0023] like Figure 1 The figure shows a specific embodiment of a styrene tar processing device, which is a styrene tar processing device, including a catalytic oil slurry pipeline 1, a vacuum residue oil pipeline 2, and a styrene tar pipeline 3. The catalytic oil slurry pipeline 1 and the vacuum residue oil pipeline 2 are connected to form a main conveying pipeline 4, and the styrene tar pipeline 3 is connected to the main conveying pipeline 4. The main conveying pipeline 4 is connected to a raw material tank 5. The outlet of the raw material tank 5 is connected to a raw material pump 6 through a pipeline, and the raw material pump 6 is connected to a heating furnace 7 through a pipeline. The heating furnace 7 is connected to a coke tower 8 through a pipeline. The catalytic oil slurry pipeline 1, the vacuum residue oil pipeline 2, and the styrene tar pipeline 3 are all connected to valves. The main conveying pipeline 4 and the pipeline between the raw material pump 6 and the heating furnace 7 are all connected to heat exchangers 9. The catalytic oil slurry pipeline 1 is provided with two valves, and the pipeline between the raw material pump 6 and the heating furnace 7 is connected to two heat exchangers 9.

[0024] A method for processing styrene tar, the method comprising the following steps:

[0025] 1) Confirm that the processing device is running smoothly, the styrene tar pipeline 3 is purged, airtight, and replaced to ensure that there is no residual moisture in the styrene tar pipeline 3;

[0026] 2) connecting the styrene tar pipeline 3 to an external styrene device or tank farm to supply styrene tar, and controlling the pressure in the styrene tar pipeline 3 to be higher than the pressure in the raw material tank 5; and the valves in the catalytic oil slurry pipeline 1 and the vacuum residue oil pipeline 2 are both in an open state;

[0027] 3) Slowly open the valve on the styrene tar pipeline 3 to control the flow rate of the tar to be within 1% of the total feed flow rate;

[0028] 4) The mixed raw material of catalytic oil slurry, vacuum residue oil and styrene tar is pumped out by raw material pump 6, heat-exchanged to 280°C by heat exchanger and enters heating furnace 7, and is sent to coke tower 8 for cracking and condensation reaction after being heated to 500°C. The oil and gas after the reaction in coke tower 8 enters fractionation tower to distill naphtha, diesel and wax oil fractions, and coke is generated in the coke tower.

[0029] According to the composition table 1 of styrene tar, the distillation range of styrene tar material is very close to the heavy wax oil of the refinery (see Table 2), and the terminal distillation point is higher than that of heavy wax oil, so it can be processed in the vacuum residue processing unit. However, this tar contains components such as oil styrene, α-methylstyrene, n-isopropylbenzene, and 1.08% polymer. If it is processed in the residue hydrogenation unit, it will cause catalyst deactivation. Then the main consideration is to process it in the delayed coking unit. According to the distillation range analysis data of styrene tar, after reaction and fractionation in the delayed coking unit, 70% is converted into coking diesel, 15% is converted into coking wax oil, and 15% is converted into petroleum coke, which has good economic benefits.

[0030] Table 1. Properties of styrene tar

[0031] Distillation range [℃] Analyze the results IBP 243 10％ 278 30％ 290 50％ 310 70％ 354 90％ 486 95％ 546 FBP 570 <![CDATA[Kinematic viscosity (100 °C) [mm 2 / s]]]> 3.4 Styrene [%] 4.13 α-Methylstyrene[%(mass fraction)] 4.01 Cumene [% (mass fraction)] 0.01 Polymer content [% (mass fraction)] 1.08 n-Propylbenzene[%(mass fraction)] 0.13 Diethylbenzene[%(mass fraction)] 0.20

[0032] Table 2. Properties of coking heavy wax oil

[0033] Distillation range [℃] Analyze the results IBP 287 10％ 369 30％ 390 50％ 409 70％ 422 90％ 446 95％ 459 FBP <![CDATA[Kinematic viscosity (100 °C) [mm 2 / s]]]> 3.4

[0034] The main risks of processing styrene tar through styrene tar pipeline 3 into the main conveying pipeline 4 are: scaling of the raw material heat exchanger and coking of the heating furnace tube. Therefore, it is necessary to conduct mixing and sedimentation experiments on styrene tar, catalytic oil slurry and vacuum residue oil to determine the miscibility and scaling tendency of this material with the coking raw material. After sampling, the two materials were mixed in equal proportions and allowed to settle for 24 hours. The results showed that the miscibility was very good, and no stratification occurred after 24 hours of sedimentation, which greatly reduced the risk of scaling and coking. It was determined that mixing styrene tar, catalytic oil slurry and vacuum residue oil was feasible.

[0035] Whether styrene tar is directly supplied from the device or supplied from the oil tank, the temperature is lower than 100°C. Therefore, after styrene tar is mixed with vacuum residue oil and catalytic oil slurry in the feed line, it enters the raw material tank 5 of the device after heat exchange in the heat exchanger 9 to increase the temperature. The mixed raw material is extracted by the raw material pump 6, and enters the heating furnace after heat exchange to 280°C through several groups of heat exchangers. After heating to 500°C, it is sent to the coke tower 8 for cracking and condensation reaction. The oil and gas after the reaction in the coke tower 8 enter the fractionation tower to distill naphtha, diesel, and wax oil fractions, and coke is generated in the coke tower 8. According to the analysis data of styrene tar, after the reaction and fractionation of the coking device, 70% is generated as coking diesel, 15% is generated as coking wax oil, and 15% is generated as coke. According to the tar output of 600,000 tons / year styrene device of 10,000 tons / year, when a set of delayed coking device with a scale of 3.2 million tons / year is processed, the proportion of styrene tar in the raw material is only 0.3%. The lower processing ratio is also conducive to the long-term operation of the device.

[0036] Finally, it should be noted that the present invention is not limited to the above embodiments, and there are many variations. All variations that can be directly derived or associated with the content disclosed by ordinary technicians in this field should be considered as the protection scope of the present invention.

Claims

1. A processing device for styrene tar, characterized in that: It comprises a catalytic oil slurry pipeline (1), a vacuum residue oil pipeline (2), and a styrene tar pipeline (3); the catalytic oil slurry pipeline (1) and the vacuum residue oil pipeline (2) are connected to form a main transport pipeline (4); the styrene tar pipeline (3) is connected to the main transport pipeline (4); the main transport pipeline (4) is connected to a raw material tank (5); the outlet of the raw material tank (5) is connected to a raw material pump (6) via a pipeline; the raw material pump (6) is connected to a heating furnace (7) via a pipeline; and the heating furnace (7) is connected to a coke tower (8) via a pipeline; The catalytic oil slurry pipeline (1), the vacuum residue oil pipeline (2), and the styrene tar pipeline (3) are all connected with valves; The main delivery pipeline (4) and the pipeline between the raw material pump (6) and the heating furnace (7) are all connected to a heat exchanger (9).

2. A styrene tar processing device according to claim 1, characterized in that: The catalytic oil slurry pipeline (1) is provided with two valves.

3. A styrene tar processing device according to claim 1, characterized in that: Two heat exchangers (9) are connected to the pipeline between the raw material pump (6) and the heating furnace (7).

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