Mixed C4 separation energy-saving device

Abstract

The utility model belongs to the technical field of separation devices, and particularly relates to a mixed C4 separation energy-saving device. Comprising a debutanizer, a light component outlet of the debutanizer is connected with a hot end inlet of a first heat exchanger, and a hot end outlet of the first heat exchanger is connected with a debutanizer condenser; a heavy component outlet of the debutanizer is respectively connected with a cold end inlet of the second heat exchanger and a feeding hole of the depentanizer, and a cold end outlet of the second heat exchanger is connected with a tower kettle of the debutanizer; a light component outlet of the depentanizer is connected with a hot end inlet of the second heat exchanger, and a hot end outlet of the second heat exchanger is connected with the depentanizer condenser; the system further comprises a mixed C4 pipeline which flows through the cold end of the first heat exchanger and is connected with the feed port of the debutanizer. According to the device, waste heat of gas phases at the tops of the debutanizer and the depentanizer is fully recycled through a heat exchange mechanism, so that the energy loss is reduced, and the energy utilization efficiency of the whole system is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of separation device, and specifically relates to a mixed carbon four separation energy-saving device. BACKGROUND

[0002] Steam cracking mixed carbon four, as an important by-product in the steam cracking process, is mainly produced by thermal cracking reaction of naphtha, light hydrocarbon and other raw materials, and contains butane, butene, butadiene and other carbon four mixtures. The yield of this mixture is closely related to the cracking raw material and operating conditions. In particular, in the cracking process using naphtha as the raw material, the yield of carbon four usually accounts for 40-50% of the ethylene yield, and the olefin content is as high as 93%, mainly butadiene and isobutene, and also contains a small amount of alkane.

[0003] At present, the recovery technology of mixed carbon four mainly relies on the rectification separation method. This method is based on the difference in relative volatility of C4 and C5+ components, and realizes the effective separation of C4 and C5+ components through a rectification tower. However, due to the limitation of the rectification principle itself, this separation process often needs to consume a large amount of energy. In actual industrial application, in order to meet the high-efficiency separation demand of mixed carbon four, multiple rectification towers and corresponding condensation and reflux systems need to be configured, which not only increases the complexity of the equipment, but also significantly increases the energy consumption in the operation process.

[0004] Therefore, although the rectification separation method is relatively mature in technology and can realize the effective separation of mixed carbon four, its high energy consumption cost has become a key factor restricting the popularization and application of the technology. Therefore, it is particularly important to develop a mixed carbon four separation device that can reduce energy consumption and improve separation efficiency. UTILITY MODEL CONTENTS

[0005] In view of the above deficiencies in the prior art, the purpose of the utility model is to provide a mixed carbon four separation energy-saving device, which fully recovers and utilizes the waste heat of the debutanizer and depentanizer overhead gas phase through a heat exchange mechanism, significantly reduces the use demand of steam and circulating water, thereby realizing the energy-saving effect, not only reducing the energy loss, but also improving the energy utilization efficiency of the whole system.

[0006] The utility model is implemented by adopting the following technical solutions:

[0007] The mixed carbon four separation energy-saving device, comprising a de-butane column, a light component outlet of the de-butane column being connected with a hot end inlet of a first heat exchanger through a pipeline, a hot end outlet of the first heat exchanger being connected with a de-butane column condenser through a pipeline, an outlet of the de-butane column condenser being connected with a reflux liquid inlet of the de-butane column and a butane storage tank through pipelines respectively; a heavy component outlet of the de-butane column being connected with a cold end inlet of a second heat exchanger and a feed inlet of a de-pentane column through pipelines respectively, a cold end outlet of the second heat exchanger being connected with a column still of the de-butane column through a pipeline; a light component outlet of the de-pentane column being connected with a hot end inlet of the second heat exchanger through a pipeline, a hot end outlet of the second heat exchanger being connected with a de-pentane column condenser through a pipeline, an outlet of the de-pentane column condenser being connected with a reflux liquid inlet of the de-pentane column and a pentane storage tank through pipelines respectively; a heavy component outlet of the de-pentane column being connected with a de-pentane column reboiler and a cracked gasoline hydrogenation device through pipelines respectively, an outlet of the de-pentane column reboiler being connected with a reboiler reflux inlet of the de-pentane column through a pipeline; further comprising a steam cracking device, a feed pipeline of the steam cracking device passing through a cold end of the first heat exchanger.

[0008] The light component outlet pipelines of the de-butane column and the de-pentane column are respectively provided with pressure transmitters and flow control valves.

[0009] The cold end outlet pipelines of the first heat exchanger and the second heat exchanger are respectively provided with temperature controllers and flow controllers.

[0010] The mixed carbon four separation energy-saving device further comprises a mixed carbon four pipeline connected with a feed inlet of the de-butane column, the mixed carbon four pipeline being provided with a filter and a dehydrator.

[0011] The outlet pipelines of the de-butane column condenser and the de-pentane column condenser are respectively provided with online component analyzers.

[0012] The heavy component outlet pipeline of the de-pentane column is provided with an online component monitor.

[0013] The mixed carbon four separation energy-saving device is mainly used for efficient separation of mixed C4 and C5+ fractions, and the mixed fraction mainly comprises carbon four diene hydrocarbon, carbon four olefin, carbon four alkane and carbon five component. The working principle is as follows:

[0014] The mixed C4 and C5+ fraction enters the device through a mixed C4 pipeline, and a filter and a dehydrator arranged on the mixed C4 pipeline ensure that the raw material entering the debutanizer is pure and free of impurities and moisture. Then the mixed raw material enters the debutanizer for rectification. Due to the difference in volatility of various components, the C4 fraction (mainly including C4 dienes, C4 olefins and C4 alkanes) is discharged from the light component outlet of the debutanizer and enters the hot end inlet of the first heat exchanger through a pipeline, so that the high-temperature gas is used to preheat the raw material entering the steam cracking device, thereby increasing the initial temperature of the raw material and facilitating the cracking reaction. The gas after heat exchange enters the debutanizer condenser for condensation. Part of the condensed C4 fraction returns to the debutanizer as reflux liquid to maintain stable operating conditions in the tower; the other part is sent to a butane storage tank for product storage.

[0015] The heavy components of the debutanizer column (mainly containing C5 components and above) enter the cold end inlet of the second heat exchanger and the feed inlet of the depentanizer through pipelines, respectively. In the second heat exchanger, the light components (mainly C5 components) at the top of the depentanizer provide heat for the cold end, achieving efficient use of heat. The heavy components entering the depentanizer are further rectified and separated in the tower. After being cooled by the condenser, part of the gas phase at the top of the tower returns to the depentanizer as reflux liquid; the other part is sent to a pentane storage tank as C5 product. The column bottom material of the depentanizer is rich in C6+ components, and this part of material is sent to the depentanizer reboiler for heating to maintain normal operation of the depentanizer, or to a cracking gasoline hydrogenation device for further treatment.

[0016] A pressure transmitter and a flow control valve are arranged on the light component outlet pipelines of the debutanizer and the depentanizer, respectively, to monitor the tower top pressure and flow in real time and ensure stable operation. A temperature controller and a flow controller are arranged on the cold end outlet pipelines of the first heat exchanger and the second heat exchanger, respectively, to adjust the heat exchange effect and flow and optimize energy utilization. An online component analyzer is arranged on the outlet pipelines of the debutanizer condenser and the depentanizer condenser, respectively, to monitor the composition of the condensed liquid in real time and ensure product quality. An online component monitor is arranged on the heavy component outlet pipeline of the depentanizer to monitor the component change of the column bottom material. The device also includes a control system which automatically adjusts the state of each valve and regulator according to the data of each sensor and monitor to ensure efficient and stable operation of the entire separation process.

[0017] Compared with the prior art, the device has the following beneficial effects:

[0018] (1) The mixed carbon four separation energy-saving device fully utilizes the waste heat of the overhead gas phase of the debutanizer and the depentanizer, recovers heat through heat exchange, effectively reduces the consumption of steam and circulating water, and thus realizes significant energy-saving effect. This waste heat utilization not only reduces energy consumption, but also improves the energy utilization efficiency of the entire system;

[0019] (2) The mixed carbon four separation energy-saving device is equipped with a perfect monitoring and control system, including a pressure transmitter, a flow control valve, a temperature controller, an online component analyzer and an online component monitor and the like. These devices can monitor and adjust the process parameters in real time, ensure the stability and efficiency of the entire separation process. At the same time, through the automatic adjustment function of the control system, the operation process is simplified, and the demand for manual intervention is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The structure diagram of the mixed carbon four separation energy-saving device is described in the utility model.

[0021] In the figure: 1, debutanizer; 2, first heat exchanger; 3, debutanizer condenser; 4, butane storage tank; 5, second heat exchanger; 6, depentanizer; 7, depentanizer condenser; 8, pentane storage tank; 9, depentanizer reboiler; 10, pyrolysis gasoline hydrogenation device; 11, steam cracking device; 12, pressure transmitter; 13, flow control valve; 14, temperature controller; 15, flow controller; 16, filter; 17, dehydrator; 18, online component analyzer; 19, online component monitor; 20, mixed carbon four pipeline. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme of the utility model more clear and obvious, the utility model will be further described in detail below in combination with the drawings.

[0023] Example 1

[0024] As Figure 1As shown, the mixed C4 separation energy-saving device comprises a debutanizer 1, a light component outlet of the debutanizer 1 is connected with a hot end inlet of a first heat exchanger 2 through a pipeline, a hot end outlet of the first heat exchanger 2 is connected with a debutanizer condenser 3 through a pipeline, an outlet of the debutanizer condenser 3 is connected with a reflux liquid inlet of the debutanizer 1 and a butane storage tank 4 through a pipeline respectively; a heavy component outlet of the debutanizer 1 is connected with a cold end inlet of a second heat exchanger 5 and a feed inlet of a depentanizer 6 through a pipeline respectively, a cold end outlet of the second heat exchanger 5 is connected with a column still of the debutanizer 1 through a pipeline; a light component outlet of the depentanizer 6 is connected with a hot end inlet of the second heat exchanger 5 through a pipeline, a hot end outlet of the second heat exchanger 5 is connected with a depentanizer condenser 7 through a pipeline, an outlet of the depentanizer condenser 7 is connected with a reflux liquid inlet of the depentanizer 6 and a pentane storage tank 8 through a pipeline respectively; a heavy component outlet of the depentanizer 6 is connected with a depentanizer reboiler 9 and a pyrolysis gasoline hydrogenation device 10 through a pipeline respectively, an outlet of the depentanizer reboiler 9 is connected with a reboiler reflux inlet of the depentanizer 6 through a pipeline; the device further comprises a steam cracking device 11, a feed pipeline of the steam cracking device 11 passes through a cold end of the first heat exchanger 2.

[0025] A pressure transmitter 12 and a flow control valve 13 are arranged on the light component outlet pipelines of the debutanizer 1 and the depentanizer 6 respectively.

[0026] A temperature controller 14 and a flow controller 15 are arranged on the cold end outlet pipelines of the first heat exchanger 2 and the second heat exchanger 5 respectively.

[0027] The mixed C4 separation energy-saving device further comprises a mixed C4 pipeline 20 connected with a feed inlet of the debutanizer 1, the mixed C4 pipeline 20 is provided with a filter 16 and a dehydrator 17.

[0028] An online component analyzer 18 is arranged on the outlet pipelines of the debutanizer condenser 3 and the depentanizer condenser 7 respectively.

[0029] An online component monitor 19 is arranged on the heavy component outlet pipeline of the depentanizer 6.

[0030] The mixed C4 separation energy-saving device further comprises a control system.

[0031] When working, the specific steps are as follows:

[0032] The mixed C4 and C5+ fraction flows into the device through the mixed carbon four pipeline 20, first passes through the filter 16 to remove solid impurities, and then passes through the dehydrator 17 to remove moisture, to ensure the purity of the raw material. Subsequently, it enters the debutanizing tower 1 through the feed port of the debutanizing tower 1, and the rectification process begins. In the debutanizing tower 1, due to the difference in volatility of each component, the lighter carbon four fraction (mainly including carbon four diene hydrocarbon, carbon four olefin and carbon four alkane) is removed from the light component outlet of the tower. The removed carbon four fraction enters the hot end inlet of the first heat exchanger 2 through the pipeline, and is heat exchanged through the first heat exchanger 2 to preheat the raw material entering the steam cracking device 11. The heat-exchanged fraction enters the debutanizing tower condenser 3 for condensation. The condensed carbon four fraction flows out of the outlet of the debutanizing tower condenser 3 and is divided into two paths: one path returns to the debutanizing tower 1 as reflux liquid to maintain stable operating conditions in the tower. The other path is directly sent to the butane storage tank 4 as a product for storage. The heavy component (mainly including carbon five component and above) of the debutanizing tower 1 flows out of the heavy component outlet of the tower and is divided into two paths: one path enters the cold end inlet of the second heat exchanger 5 through the pipeline and is preheated using the heat provided by the light component at the top of the de-pentanizing tower 6. The other path is directly introduced into the feed port of the de-pentanizing tower 6 for further rectification and separation.

[0033] In the de-pentanizing tower 6, the heavy component is further separated, and the light component (mainly carbon five component) at the top of the tower is removed from the light component outlet of the tower. The removed carbon five component enters the hot end inlet of the second heat exchanger 5 through the pipeline, preheats the heavy component at the bottom of the second heat exchanger, and then enters the de-pentanizing tower condenser 7 for condensation. The condensed carbon five fraction flows out of the outlet of the de-pentanizing tower condenser 7 and is divided into two paths: one path returns to the de-pentanizing tower 6 as reflux liquid to maintain stable operating conditions in the tower. The other path is directly sent to the pentane storage tank 8 as a product for storage. The heavy component of the de-pentanizing tower 6 is rich in C6+ component, which flows out of the heavy component outlet of the tower and is divided into two paths: one path is sent to the de-pentanizing tower reboiler 9 for heating to maintain normal operation of the de-pentanizing tower. The other path is sent to the cracking gasoline hydrogenation device 10 for further treatment. On the light component outlet pipelines of the debutanizing tower 1 and the de-pentanizing tower 6, respectively, a pressure transmitter 12 and a flow control valve 13 are provided to monitor the tower top pressure and flow in real time.

[0034] On the cold end outlet pipelines of the first heat exchanger 2 and the second heat exchanger 5, respectively, a temperature controller 14 and a flow controller 15 are provided to adjust the heat exchange effect and flow. On the outlet pipelines of the debutanizing tower condenser 3 and the de-pentanizing tower condenser 7, respectively, an online component analyzer 18 is provided to monitor the composition of the condensed liquid in real time. An online component monitor 19 is provided on the heavy component outlet pipeline of the de-pentanizing tower 6 to monitor the component change of the heavy component at the bottom of the tower. The control system automatically adjusts the state of each control valve and regulator according to the data of each sensor and monitor to ensure efficient and stable operation of the entire separation process.

Claims

1. A mixed C4 separation energy saving device, characterized in that, The application relates to a debutanizer (1), the light component outlet of the debutanizer (1) is connected with the hot end inlet of a first heat exchanger (2) through a pipeline, the hot end outlet of the first heat exchanger (2) is connected with a debutanizer condenser (3) through a pipeline, the outlet of the debutanizer condenser (3) is connected with the reflux liquid inlet of the debutanizer (1) and a butane storage tank (4) through pipelines respectively; the heavy component outlet of the debutanizer (1) is connected with the cold end inlet of a second heat exchanger (5) and the feed inlet of a depentanizer (6) through pipelines respectively, the cold end outlet of the second heat exchanger (5) is connected with the tower kettle of the debutanizer (1) through a pipeline; the light component outlet of the depentanizer (6) is connected with the hot end inlet of the second heat exchanger (5) through a pipeline, the hot end outlet of the second heat exchanger (5) is connected with a depentanizer condenser (7) through a pipeline, the outlet of the depentanizer condenser (7) is connected with the reflux liquid inlet of the depentanizer (6) and a pentane storage tank (8) through pipelines respectively; the heavy component outlet of the depentanizer (6) is connected with a depentanizer reboiler (9) and a pyrolysis gasoline hydrogenation device (10) through pipelines respectively, the outlet of the depentanizer reboiler (9) is connected with the reboiler reflux inlet of the depentanizer (6) through a pipeline; the application further comprises a steam cracking device (11), and the feed pipeline of the steam cracking device (11) passes through the cold end of the first heat exchanger (2).

2. The mixed C4 separation energy-saving device according to claim 1, characterized in that, Pressure transmitters (12) and flow control valves (13) are arranged on the light component outlet pipelines of the debutanizer (1) and the depentanizer (6) respectively.

3. The mixed C4 separation energy-saving device according to claim 1, characterized in that, Temperature controllers (14) and flow controllers (15) are arranged on the cold end outlet pipelines of the first heat exchanger (2) and the second heat exchanger (5) respectively.

4. The mixed C4 separation energy-saving device according to claim 1, characterized in that, A mixed carbon four pipeline (20) connected with the feed inlet of the debutanizer (1) is further comprised, and a filter (16) and a dehydrator (17) are arranged on the mixed carbon four pipeline (20).

5. The mixed C4 separation energy-saving device according to claim 1, characterized in that, Online component analyzers (18) are arranged on the outlet pipelines of the debutanizer condenser (3) and the depentanizer condenser (7) respectively.

6. The mixed C4 separation energy-saving device according to claim 1, characterized in that, An online component monitor (19) is arranged on the heavy component outlet pipeline of the depentanizer (6).

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