A system for blending crude isopentene in a naphtha hydrogenation unit

Abstract

The utility model discloses a system for blending crude isopentene in a naphtha hydrogenation device, comprising a coking naphtha feed buffer tank, wherein the coking naphtha feed buffer tank is connected with two feed pipelines for respectively conveying crude isopentene and coking naphtha, wherein the coking naphtha feed buffer tank is connected to the top of a diolefin reactor through pipelines, wherein the outlet end at the bottom of the diolefin reactor is connected with a main reactor through pipelines, wherein the main reactor is sequentially connected with a dehydrogenation reactor, a high separation tank, a stripping tower, a dechlorination reactor and a naphtha fractionation tower through pipelines, wherein the upper and lower ends of the naphtha fractionation tower are respectively connected with discharge pipelines for respectively conveying light naphtha and refined naphtha, and the system has the technical characteristics of simple structure, being able to realize the regulation of raw material composition and fractionation and cutting operation, increasing the raw material of an ethylene device, and realizing the blending of crude isopentene to produce ethylene material.

Description

Technical Field

[0001] The utility model relates to a system for blending crude isopentene, and more specifically to a system for blending crude isopentene in a naphtha hydrogenation device, and belongs to the field of petrochemical industry. Background Art

[0002] At present, the design output of crude isopentene as a byproduct of C5 separation unit of general factories and enterprises is 50,000 tons / year, which is mainly composed of C5 components, with an olefin content of about 36% and a diene value of 0.7gI / 100g. For detailed analysis, see Table 1 and Table 2. There is no material processing route in the overall processing flow. Therefore, it is a feasible research path to use the 1# naphtha hydrogenation unit for hydrogenation and deolefination, and then separate the light naphtha through a distillation tower to remove ethylene as a raw material after refining reaction. Utility Model Content

[0003] In order to solve the above-mentioned problems of the prior art, the utility model provides a system for blending crude isopentene in a naphtha hydrogenation unit, which has the technical characteristics of simple structure, being able to realize the regulation of raw material composition and fractionation and cutting operations, increasing the production of raw materials for ethylene units, and realizing the blending of crude isopentene to produce ethylene materials.

[0004] In order to achieve the above purpose, the utility model is implemented by the following technical solutions:

[0005] A system for blending crude isopentene in a naphtha hydrogenation unit comprises a coking naphtha feed buffer tank, the coking naphtha feed buffer tank is connected with two feed pipelines for respectively conveying crude isopentene and coking naphtha, the coking naphtha feed buffer tank is connected to the top of a diolefin reactor through pipelines, the outlet end at the bottom of the diolefin reactor is connected with a main reactor through pipelines, the main reactor is sequentially connected with a dehydrogenation reactor, a high separation tank, a stripping tower, a dechlorination reactor and a naphtha fractionation tower through pipelines, and the upper and lower ends of the naphtha fractionation tower are respectively connected with discharge pipelines for respectively conveying light naphtha and refined naphtha.

[0006] Preferably, it also includes a feed heating furnace, the inlet end of which is connected to a feed pipeline for conveying straight-run heavy petroleum oil, and the outlet end of the feed heating furnace is connected to the main reactor after being connected to the outlet end of the diene reactor through a pipeline.

[0007] Preferably, a delivery pump is connected to the feed pipeline between the coking naphtha feed buffer tank and the diene reactor and to the feed pipeline at the inlet end of the feed heating furnace.

[0008] Preferably, the discharge pipeline at the upper end of the naphtha fractionation tower is connected to a reflux tank, and the outlet end of the reflux tank is connected to a light naphtha delivery pipeline with a delivery pump.

[0009] Preferably, the outlet end of the reflux tank is also provided with a reflux pipeline, and the reflux pipeline is connected to the upper end of the naphtha fractionation tower through a pipeline with a delivery pump.

[0010] Beneficial effects: The system has a simple structure and can realize the regulation of raw material composition and fractionation and cutting operations to increase the production of raw materials for ethylene units; it can realize the production of ethylene materials by blending crude isopentene. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the overall structure of the utility model. DETAILED DESCRIPTION

[0012] 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.

[0013] like Figure 1 The present invention shows a specific embodiment of a system for blending crude isopentene in a naphtha hydrogenation unit, a system for blending crude isopentene in a naphtha hydrogenation unit, comprising a coking naphtha feed buffer tank 1, the coking naphtha feed buffer tank 1 is connected with two feed pipelines to respectively convey crude isopentene and coking naphtha, the coking naphtha feed buffer tank 1 is connected to the top of a diene reactor 2 through a pipeline, the outlet end of the bottom of the diene reactor 2 is connected with a main reactor 3 through a pipeline, the main reactor 3 is sequentially connected with a dehydrogenation reactor 4, a high separation tank 5, a stripping tower 6, a dechlorination reactor 7, and a naphtha fractionation tower 8 through pipelines, the upper and lower ends of the naphtha fractionation tower 8 are respectively connected with discharge pipelines to respectively convey light naphtha and refined naphtha. It also comprises a feed heating furnace 9, the inlet end of the feed heating furnace 9 is connected with a feed pipeline for conveying straight-run heavy petroleum oil, and the outlet end of the feed heating furnace 9 is connected to the outlet end of the diene reactor 2 through a pipeline and then connected to the main reactor 3. A delivery pump is connected to the feed pipeline between the coking naphtha feed buffer tank 1 and the diene reactor 2 and the inlet end of the feed heating furnace 9. The discharge pipeline at the upper end of the naphtha fractionation tower is connected to a reflux tank 10, and the outlet end of the reflux tank 10 is connected to a light naphtha delivery pipeline with a delivery pump. A reflux pipeline 11 is also provided at the outlet end of the reflux tank 10, and the reflux pipeline 11 is connected to the upper end of the naphtha fractionation tower through a pipeline with a delivery pump.

[0014] Operation process:

[0015] The mixed raw material of crude isopentene and coking naphtha enters the coking naphtha feed buffer tank 1, and enters the diolefin reactor 2 after heating, and the temperature and pressure are set according to actual needs to remove diolefins. The material after diolefin removal is mixed with the heated straight naphtha and enters the main reactor of hydrofining, and the temperature and pressure are set according to actual needs to desulfurize, denitrogenate and remove olefins. The reaction product is separated into gas and liquid, and the reaction oil enters the stripping tower 6 to remove hydrogen sulfide, and then enters the naphtha fractionation tower 8 to separate the light naphtha and send it to the ethylene device, and the separated and refined naphtha is sent to the reforming device.

[0016] The technical solution of the present application realizes the processing of crude isopentene, achieving the effects of deolefination, desulfurization, denitrogenation and deoxygenation, and separating light naphtha which can be transported to ethylene as a raw material. Specifically, the discharge pipeline at the upper end of the naphtha fractionation tower 8 realizes the delivery of light naphtha to ethylene as a raw material. The discharge pipeline at the lower end of the naphtha fractionation tower 8 realizes the delivery of refined naphtha to the reforming unit.

[0017] For example, 12% crude isopentene is added to coker naphtha to form a mixed raw material, and the properties of the mixed raw material are shown in Table 1.

[0018] Table 1 Properties of mixed raw materials

[0019]

[0020] Table 2 Analysis of crude isopentene composition

[0021]

[0022]

[0023] The mixed raw material is pressurized and heat exchanged, mixed with hydrogen, heated to 152°C and enters a reactor filled with a de-diene catalyst for de-diene reaction. The reaction temperature is controlled at 152°C, the reaction pressure is controlled at 4MPa, and the reaction temperature rises by 10.2°C.

[0024] The diolefin removal reaction product and straight-run naphtha are mixed and then enter the main reactor filled with a refining catalyst for hydrogenation refining reaction. The reaction pressure is 4.0MPa, the reaction temperature is 292℃, and the reaction temperature rise is 17.5℃. The reaction product is separated into gas and liquid, and the reaction oil enters the stripping tower to remove hydrogen sulfide and then enters the naphtha fractionation tower. The material passes through the naphtha fractionation tower to separate light naphtha and is sent to the ethylene unit as raw material.

[0025] Table 3 Comparison of operating parameters between existing process and process of the present invention

[0026] project Existing process Process of the present invention Fresh feed rate, t / h 427 420 Crude isopentene blending amount, t / h 0 7 R1101 inlet temperature, °C 152 151-152 R1101 temperature rise, ℃ 10 10.2 R1102 average temperature, °C 292 292 R1102 temperature rise, ℃ 17 17.5 Reaction pressure, MPa 4 4 Light naphtha output after hydrogenation, t / h 90 97

[0027] After hydrofining, the light naphtha production increased by 7t / h. The following table shows the composition changes of light naphtha before and after blending.

[0028] Table 4 Mass fraction composition of light naphtha before blending with crude isopentene

[0029] Cnum np ip O N A C.SUM C5 55.02 23.7 0 3.38 0 82.1 C6 0.86 16.72 0 0.08 0.18 17.84 T.Sum 55.88 40.42 0 3.46 0.18 99.94

[0030] Table 5 Mass fraction composition of light naphtha after blending with crude isopentene

[0031] Cnum np ip O N A C.SUM C5 45.57 49.03 0 1.07 0 92.67 C6 0.33 6.87 0 0.04 0.06 7.3 T.Sum 45.9 55.9 0 1.11 0.06 99.97

[0032] The analysis data showed that the light naphtha C5 component oil increased from 82.1% to 92.67% after blending, indicating that crude isopentene was converted into light naphtha after reaction and separation.

[0033] 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 system for blending crude isopentene in a naphtha hydrogenation unit, characterized in that: The invention comprises a coker naphtha feed buffer tank (1), wherein the coker naphtha feed buffer tank (1) is connected to two feed pipelines for respectively conveying crude isopentene and coker naphtha, wherein the coker naphtha feed buffer tank (1) is connected to the top of a diene reactor (2) via pipelines, wherein the outlet end at the bottom of the diene reactor (2) is connected to a main reactor (3) via pipelines, wherein the main reactor (3) is sequentially connected to a dehydrogenation reactor (4), a high separation tank (5), a stripping tower (6), a dechlorination reactor (7), and a naphtha fractionation tower (8) via pipelines, wherein the upper and lower ends of the naphtha fractionation tower (8) are respectively connected to discharge pipelines for respectively conveying light naphtha and refined naphtha.

2. A system for blending crude isopentene in a naphtha hydrogenation unit according to claim 1, characterized in that: It also includes a feed heating furnace (9), the inlet end of the feed heating furnace (9) is connected to a feed pipeline for conveying straight-run heavy petroleum, and the outlet end of the feed heating furnace (9) is connected to the outlet end of the diene reactor (2) through a pipeline and then connected to the main reactor (3).

3. A system for blending crude isopentene in a naphtha hydrogenation unit according to claim 1 or 2, characterized in that: A delivery pump is connected to the feed pipeline between the coking naphtha feed buffer tank (1) and the diene reactor (2) and to the inlet end of the feed heating furnace (9).

4. The system for blending crude isopentene in a naphtha hydrogenation unit according to claim 1, characterized in that: The discharge pipeline at the upper end of the naphtha fractionation tower is connected to a reflux tank (10), and the outlet end of the reflux tank (10) is connected to a light naphtha delivery pipeline with a delivery pump.

5. A system for blending crude isopentene in a naphtha hydrogenation unit according to claim 4, characterized in that: The outlet end of the reflux tank (10) is also provided with a reflux pipeline (11), and the reflux pipeline (11) is connected to the upper end of the naphtha fractionation tower via a pipeline with a delivery pump.

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