Novel heat exchange device
By designing a new heat exchange device in chemical production, using high-temperature process condensate to recover heat energy to heat fresh benzene, and optimizing the heat exchange process between hot ethylbenzene and fresh benzene, the increase in steam consumption caused by the decrease in the hot ethylbenzene temperature is solved. and the issue of heat energy waste have achieved cost savings and improved production efficiency.
Patent Information
- Application Number
- CN202421121786.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-22
- Publication Date
- 2025-01-17
- Estimated Expiration
- 2034-05-22
AI Technical Summary
In the chemical production process, especially in the styrene production process, the decrease in the temperature of hot ethylbenzene leads to an increase in steam consumption in the dehydrogenation reaction, and the high-temperature condensate thermal energy is not fully recovered, resulting in waste of the device's heat energy and the post-treatment cost of the circulating water system improve.
A new heat exchange device was designed, through the combination of ethylbenzene tower, top condenser, reflux tank and reboiler, the heat energy of condensate is recovered by high-temperature process to heat fresh benzene, and a temperature detection is set in the heat exchanger. The heat exchange process of hot ethylbenzene and fresh benzene is optimized, and the consumption of hot ethylbenzene and steam use are reduced.
It effectively reduces the cost of recycled water after treatment, reduces steam consumption in dehydrogenation reaction, reduces production costs, and saves about 54 million yuan of steam costs per year.
Smart Images
Figure CN222357982U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of heat exchange devices, and specifically relates to a novel heat exchange device. Background Art
[0002] In the chemical production process, the factors that affect chemical reactions mainly include: catalyst activity, reaction temperature, reaction pressure and other conditions. Among them, reaction temperature, as one of the prerequisites for triggering chemical reactions, plays an indispensable role in energy consumption control. In the styrene production process, in order to reduce the consumption of fresh benzene dehydration steam, the method of heat exchange between fresh benzene and the hot ethylbenzene at the top of the ethylbenzene tower is usually used to provide heat for the feed fresh benzene. However, the hot ethylbenzene after heat exchange is used as the raw material for the dehydrogenation reaction. Its temperature decrease will lead to an increase in steam consumption in the dehydrogenation section. In addition, the heat energy of the high-temperature condensate in the bottom of the stripping tower is directly discharged into the circulating water system without being fully recovered, which not only causes a waste of thermal energy in the device, but also increases the post-treatment cost of the circulating water system. Utility Model Content
[0003] In order to solve the above-mentioned deficiencies of the prior art, the utility model provides a novel heat exchange device, and its technical solution includes:
[0004] The ethylbenzene tower, the top condenser, the reflux tank and the reboiler are characterized in that: the ethylbenzene tower is connected with the reboiler through a pipeline, the high-pressure steam feed line is connected with the shell side inlet of the reboiler, the heavy components are sent to the post-distillation system through the ethylbenzene tower discharge line, the ethylbenzene tower top discharge line is connected with the top condenser tube side inlet, the shell side by-product steam line of the top condenser is connected with the steam network, the material after condensation in the top condenser is sent to the reflux tank, a small amount of hot ethylbenzene in the reflux tank is sent to the ethylbenzene tower through a reflux pump, and most of the hot ethylbenzene passes through the heat exchanger I After heat exchange in the tube side, it is sent to the dehydrogenation reaction system. Temperature detector I and temperature detector II are installed on the inlet and outlet pipelines of the tube side of heat exchanger I. Heat exchanger II and temperature detector III are added to the fresh benzene feed line. The shell side of heat exchanger II is connected to the high-temperature process condensate line. Temperature detector V and temperature detector VI are installed on the high-temperature condensate inlet and outlet pipelines. The discharge line of the tube side of heat exchanger II is connected to the shell side of heat exchanger I. The discharge line of the shell side of heat exchanger I is connected to the demand end of raw benzene. A temperature detector IV is installed on the discharge of the shell side of heat exchanger I.
[0005] Furthermore, the feed temperature range of the tube side of the heat exchanger I is 153-155°C.
[0006] Furthermore, the outlet temperature of the hot ethylbenzene in the tube pass of the heat exchanger I is in the range of 130 to 135°C.
[0007] Furthermore, the discharge temperature range of the raw material benzene in the shell side of the heat exchanger I is 115-118°C.
[0008] Furthermore, the process condensate water supply temperature ranges from 78 to 80°C.
[0009] Furthermore, the process condensate return water temperature ranges from 45 to 47°C.
[0010] Compared with the prior art, the utility model has the following advantages:
[0011] 1. By designing a new type of heat exchange device, the heat energy in the high-temperature process condensate is fully recovered and utilized to heat fresh benzene. The cooled process condensate is discharged into the circulating water system, which will effectively reduce the post-processing cost of circulating water.
[0012] 2. The fresh benzene heated by heat exchange with the high-temperature process condensate is further exchanged with hot ethylbenzene. Compared with the traditional production process, the research of this project effectively reduces the thermal energy consumption of hot ethylbenzene, thereby increasing the ethylbenzene feed temperature of the dehydrogenation reaction, reducing the steam consumption of the dehydrogenation reaction, and reducing production costs.
[0013] 3. By comparing with traditional heating technology, it is found that to achieve the same heating effect, the steam consumption is reduced by about 0.3t / t.sm. Assuming that the styrene unit is fully loaded and the steam price is 300 yuan / ton, the steam cost can be saved by about 54 million yuan per year. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a schematic diagram of the process of the utility model.
[0015] Figures: 1 ethylbenzene tower, 2 reboiler, 3 top condenser, 4 reflux tank, 5 reflux pump, 6 temperature detector I, 7 temperature detector IV, 8 heat exchanger I, 9 heat exchanger II, 10 temperature detector V, 11 temperature detector VI, 12 temperature detector III, 13 temperature detector II. DETAILED DESCRIPTION
[0016] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.
[0017] Example
[0018] like Figure 1 As shown:
[0019] A novel heat exchange device comprises an ethylbenzene tower 1, a tower top condenser 3, a reflux tank 4 and a reboiler 2, characterized in that: the ethylbenzene tower 1 is connected to the reboiler 2 through a pipeline, a high-pressure steam feed line is connected to the shell side inlet of the reboiler 2, the heavy components are sent to the post-distillation system through the ethylbenzene tower 1 discharge line, the ethylbenzene tower 1 top discharge line is connected to the tower top condenser 3 tube side inlet, the tower top condenser 3 shell side byproduct steam line is connected to the steam network, the material after condensation in the tower top condenser is sent to the reflux tank 4, a small amount of hot ethylbenzene in the reflux tank 4 is sent to the ethylbenzene tower 1 through a reflux pump 5, and most of the hot ethylbenzene is sent to the ethylbenzene tower 1 through a reflux pump 5. After heat exchange in the tube side of heat exchanger Ⅰ8, it is sent to the dehydrogenation reaction system. Temperature detector Ⅰ6 and temperature detector Ⅱ13 are installed on the inlet and outlet pipelines of the tube side of heat exchanger Ⅰ8. Heat exchanger Ⅱ9 and temperature detector Ⅲ12 are added to the fresh benzene feed line. The shell side of heat exchanger Ⅱ9 is connected to the high-temperature process condensate line. Temperature detector Ⅴ10 and temperature detector Ⅵ11 are installed on the high-temperature condensate inlet and outlet pipelines. The outlet line of the tube side of heat exchanger Ⅱ9 is connected to the shell side of heat exchanger Ⅰ8. The outlet line of the shell side of heat exchanger Ⅰ8 is connected to the demand end of raw benzene. A temperature detector Ⅳ7 is installed on the shell side outlet of heat exchanger Ⅰ8.
[0020] The high-pressure steam enters the reboiler 2 and is further vaporized and then enters the ethylbenzene tower 1. The hot ethylbenzene generated in the ethylbenzene tower enters the top condenser 3 to reduce the temperature of the hot ethylbenzene and separate it from the by-product steam. The by-product steam enters the steam network and enters the reflux tank 4 through the hot ethylbenzene in the top condenser 3. A small amount of the hot ethylbenzene is then sent to the ethylbenzene tower 1 through the reflux pump 5 to provide a heat source for the ethylbenzene tower 1. Most of the hot ethylbenzene enters the heat exchanger I 8 and is supplied to the dehydrogenation system for dehydrogenation.
[0021] The water from the high-temperature condensate in the stripping tower kettle enters the heat exchanger Ⅱ9 to heat the fresh benzene. The heated fresh benzene enters the heat exchanger Ⅰ8 to exchange heat with the hot ethylbenzene, so that the hot ethylbenzene is heated. The heated fresh benzene becomes raw benzene.
[0022] The process condensate upper water after heat exchange in the heat exchanger II 9 becomes process condensate return water and is recovered.
[0023] The feed temperature range of the heat exchanger Ⅰ8 tube side is 153~155℃, which is detected by temperature detector Ⅰ6.
[0024] The outlet temperature of hot ethylbenzene in the heat exchanger Ⅰ8 tube pass is in the range of 130~135℃, which is detected by temperature detector Ⅱ13.
[0025] The discharge temperature of the raw material benzene in the shell side of the heat exchanger I8 is in the range of 115-118°C, which is detected by the temperature detector IV7.
[0026] The process condensate inlet water temperature ranges from 78 to 80°C and is detected by a temperature detector V10. The process condensate return water temperature ranges from 45 to 47°C and is detected by a temperature detector VI11.
Claims
1. A novel heat exchange device, comprising an ethylbenzene tower (1), a tower top condenser (3), a reflux tank (4) and a reboiler (2), characterized in that: The ethylbenzene tower (1) is connected to a reboiler (2) through a pipeline, a high-pressure steam feed line is connected to the shell side inlet of the reboiler (2), the heavy components are sent to the post-distillation system through the ethylbenzene tower (1) discharge line, the top discharge line of the ethylbenzene tower (1) is connected to the tube side inlet of the top condenser (3), the shell side byproduct steam line of the top condenser (3) is connected to the steam network, the material condensed by the top condenser is sent to the reflux tank (4), a small amount of hot ethylbenzene in the reflux tank (4) is sent to the ethylbenzene tower (1) through a reflux pump (5), and most of the hot ethylbenzene is sent to the dehydrogenation reaction system after heat exchange in the tube side of the heat exchanger I (8). A temperature detector I (6) and a temperature detector II (13) are provided on the inlet and outlet pipelines of the tube side of the heat exchanger I (8); a heat exchanger II (9) and a temperature detector III (12) are additionally provided on the fresh benzene feed line; the shell side of the heat exchanger II (9) is connected to the high temperature process condensate line; a temperature detector V (10) and a temperature detector VI (11) are provided on the inlet and outlet pipelines of the high temperature condensate; the outlet line of the tube side of the heat exchanger II (9) is connected to the shell side of the heat exchanger I (8); the outlet line of the shell side of the heat exchanger I (8) is connected to the demand end of the raw material benzene; and a temperature detector IV (7) is provided on the outlet of the shell side of the heat exchanger I (8).
2. According to claim 1, a novel heat exchange device is characterized in that: The feed temperature range of the tube side of the heat exchanger I (8) is 153-155°C.
3. According to the novel heat exchange device of claim 1, it is characterized in that: The outlet temperature of the hot ethylbenzene in the tube pass of the heat exchanger I (8) is in the range of 130 to 135°C.
4. According to the novel heat exchange device of claim 1, it is characterized in that: The discharge temperature of the raw material benzene in the shell side of the heat exchanger I (8) is in the range of 115 to 118°C.