Acetone rectification system

Abstract

The utility model discloses an acetone rectification system, and relates to the technical field of isopropylbenzene production systems. The acetone rectification system comprises a rectification tower, a first reboiler and a second reboiler. And the rectifying tower is respectively communicated with the first reboiler and the second reboiler through two circulation loops. A heat source is introduced into the first reboiler, and a second outlet of the first reboiler is communicated with the exhaust unit. A second inlet of the second reboiler is communicated with a gas phase outlet of the dealkylation tower, and a second outlet of the second reboiler is communicated with a reflux tank of the dealkylation tower. According to the system, the design of double reboilers is adopted, the second reboiler is used for recovering heat of the dealkylation tower to heat materials in the rectifying tower, the heat source use amount of the first reboiler is reduced, waste heat resources are effectively utilized, use of external low-pressure steam is reduced, energy consumption is remarkably reduced, and the energy utilization efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the technical field of cumene production systems, specifically to an acetone distillation system. Background Technology

[0002] Phenol and acetone are important chemical raw materials, widely used in synthetic resins, pharmaceuticals, pesticides, and fragrances. Currently, one method for preparing phenol and acetone in the chemical industry is the cumene process. This process mainly consists of four steps: alkylation, oxidation, decomposition, and distillation. Specifically, propylene and benzene react with a catalyst to produce cumene; subsequently, cumene is oxidized in the liquid phase to produce cumene hydroperoxide (CHP). CHP is concentrated and then decomposed with sulfuric acid to obtain phenol and acetone. Finally, a decomposition liquid containing a phenol / acetone mixture is obtained through resin neutralization, followed by distillation, separation, and purification to obtain the qualified product.

[0003] In the aforementioned production process, a dehydrocarbonization tower is used to separate the products. The gaseous material output from the top of the dehydrocarbonization tower carries a large amount of heat, which is not effectively recovered and utilized in the current process. Furthermore, this gaseous material needs to be condensed for recovery, but the heat is directly lost during the condensation process, resulting in resource waste. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides an acetone distillation system.

[0005] The present invention discloses an acetone distillation system, comprising a distillation column, a first reboiler, and a second reboiler. The first circulation outlet of the distillation column is connected to the first inlet of the first reboiler, the first outlet of the first reboiler is connected to the first circulation inlet of the distillation column, the second circulation outlet of the distillation column is connected to the first inlet of the second reboiler, and the first outlet of the second reboiler is connected to the second circulation inlet of the distillation column.

[0006] The first reboiler has a heat source connected to its second inlet, a second outlet connected to the exhaust unit, a second inlet connected to the gas phase outlet of the dehydrogenation tower, and a second outlet connected to the reflux tank of the dehydrogenation tower.

[0007] According to one embodiment of the present invention, a circulation pump is provided on the pipeline connecting the second circulation outlet of the distillation column and the first inlet of the second reboiler. The inlet of the circulation pump is connected to the second circulation outlet of the distillation column, and the outlet of the circulation pump is connected to the first inlet of the second reboiler.

[0008] According to one embodiment of the present invention, a first valve is provided on the pipeline connecting the first outlet of the second reboiler and the second circulation inlet of the distillation column.

[0009] According to one embodiment of the present invention, a second valve is provided on the pipeline through which the heat source enters the second inlet of the first reboiler.

[0010] According to one embodiment of the present invention, a third valve is provided on the pipeline connecting the second inlet of the second reboiler and the gas phase outlet of the dehydrogenation tower.

[0011] According to one embodiment of the present invention, a fourth valve is provided on the pipeline connecting the second outlet of the second reboiler to the reflux trough of the dehydrogenation tower.

[0012] According to one embodiment of the present invention, the bottom temperature of the distillation column is controlled at 102°C.

[0013] According to one embodiment of the present invention, temperature sensors are respectively provided at the first outlet of the first reboiler and the first outlet of the second reboiler.

[0014] According to one embodiment of the present invention, the first reboiler and the second reboiler are shell-and-tube heat exchangers.

[0015] Compared with the prior art, the acetone distillation system of this invention has the following advantages:

[0016] This invention relates to an acetone distillation system that employs a double reboiler design. The second reboiler recovers heat released from the dehydrocarbonization column to raise the temperature of the material in the distillation column, reducing the heat source usage of the first reboiler. This method not only effectively utilizes waste heat resources from the production process but also reduces the use of external low-pressure steam, significantly lowering energy consumption and improving energy efficiency. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0018] Figure 1 This is a structural framework diagram of the acetone distillation system in the embodiment.

[0019] Explanation of reference numerals in the attached figures:

[0020] 1. Distillation column; 2. First reboiler; 3. Second reboiler; 4. Heat source; 5. Dehydrocarbonization column; 6. Reflux tank; 8. Circulation pump; 9. First valve; 10. Second valve; 11. Third valve; 12. Fourth valve. Detailed Implementation

[0021] The following illustrations disclose several embodiments of the present invention. For clarity, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit the present invention. That is, in some embodiments of the present invention, these practical details are not essential. In addition, for the sake of simplicity, some conventional structures and components will be shown in the illustrations in a simple schematic manner.

[0022] Furthermore, in this utility model, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the utility model. They are merely used to distinguish components or operations described with the same technical terms and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0023] See Figure 1 This embodiment provides an acetone distillation system, including a distillation column 1, a first reboiler 2, and a second reboiler 3. The distillation column 1 is used for the distillation and separation of acetone. The first reboiler 2 and the second reboiler 3 are used to raise the temperature of the material in the distillation column 1. The first circulation outlet of the distillation column 1 is connected to the first inlet of the first reboiler 2 via a pipe, and the first outlet of the first reboiler 2 is connected to the first circulation inlet of the distillation column 1 via a pipe. The second circulation outlet of the distillation column 1 is connected to the first inlet of the second reboiler 3 via a pipe, and the first outlet of the second reboiler 3 is connected to the second circulation inlet of the distillation column 1 via a pipe. The second inlet of the first reboiler 2 is used to introduce a heat source 4, and its second outlet is connected to an exhaust unit. The second inlet of the second reboiler 3 is connected to the gas phase outlet of a dehydrogenation column 5, and its second outlet is connected to the reflux tank 6 of the dehydrogenation column 5.

[0024] A circulation pump 8 is installed on the pipeline connecting the second circulation outlet of distillation column 1 to the first inlet of the second reboiler 3. The inlet of circulation pump 8 is connected to the second circulation outlet of distillation column 1, and the outlet of circulation pump 8 is connected to the first inlet of the second reboiler 3. A first valve 9 is installed on the pipeline connecting the first outlet of the second reboiler 3 to the second circulation inlet of distillation column 1. A second valve 10 is installed on the pipeline connecting the heat source 4 to the second inlet of the first reboiler 2. A third valve 11 is installed on the pipeline connecting the second inlet of the second reboiler 3 to the gas phase outlet of the dehydrogenation column 5. A fourth valve 12 is installed on the pipeline connecting the second outlet of the second reboiler 3 to the reflux tank 6 of the dehydrogenation column 5.

[0025] During operation, the acetone mixture enters distillation column 1 for distillation separation. Under siphon action, the material from the first circulation outlet of distillation column 1 is conveyed to the first inlet of the first reboiler 2. The first reboiler 2 heats the material through a heat source 4 introduced at its second inlet. The heated material flows out from the first outlet of the first reboiler 2 and returns to distillation column 1 via the first circulation inlet to continue participating in the distillation process. Meanwhile, the material from the second circulation outlet of distillation column 1 is conveyed to the first inlet of the second reboiler 3 via a circulation pump 8. The second reboiler 3 heats the material using the heat from the dehydrocarbonization column. The heated material flows out from the first outlet of the second reboiler 3, and after its flow rate is controlled by the second valve 10, it returns to distillation column 1 to continue participating in the distillation process.

[0026] The first reboiler 2 and the second reboiler 3 operate synchronously. The second reboiler 3 utilizes the heat from the gaseous material in the dehydrogenation tower 5 to heat the material in the distillation tower 1, thereby saving the heat source usage of the first reboiler 2. The heat source 4 for the first reboiler 2 is 1.8 MPa low-pressure steam. Calculations show that the second reboiler 3 can replace 4 T / h of low-pressure steam, reducing low-pressure steam consumption to 4 T / h. In this way, the heat generated by the dehydrogenation tower 5 is effectively recovered and utilized, reducing the use of external heat source 4 and lowering production costs.

[0027] The bottom temperature of distillation column 1 is controlled at 102℃, and the efficient operation of the distillation process is ensured by the operation of two reboilers. Temperature sensors are installed at the first outlet of the first reboiler 2 and the first outlet of the second reboiler 3 to monitor the temperature of the material at the reboiler outlet in real time, so as to accurately control the distillation process. The first reboiler 2 and the second reboiler 3 adopt shell-and-tube heat exchangers, which have good heat exchange efficiency and stability.

[0028] Through the above system structure and operation mode, the acetone distillation system can achieve efficient acetone distillation and separation. At the same time, through reasonable heat source utilization and flow control, the system's operating efficiency and stability are improved, the heat of the dehydrogenation tower is effectively recovered and utilized, and production costs are reduced.

[0029] First, the system employs a dual reboiler design, utilizing the second reboiler to recover heat released from the dehydrocarbonization tower to reheat the material in the distillation tower. This approach not only effectively utilizes waste heat resources from the production process but also reduces the use of external low-pressure steam, significantly lowering energy consumption and improving energy efficiency.

[0030] Secondly, the system is equipped with circulating pumps, valves, and temperature sensors at key locations, enabling flexible adjustment of material flow, heat supply, and temperature control according to actual production needs. The circulating pumps control the material circulation between the distillation column and the second reboiler, ensuring efficient material flow within the system. The first, second, third, and fourth valves control the flow rate of each pipeline, achieving precise heat distribution and material delivery. The temperature sensors monitor the temperature of the material at the reboiler outlet in real time, providing data support for the system's automated control. This flexible adjustment capability improves the system's adaptability and stability, enabling it to better cope with fluctuations and changes during the production process.

[0031] Furthermore, by optimizing heat utilization and system control strategies, the acetone distillation system of this application can significantly reduce production costs. Reducing the use of low-pressure steam directly lowers energy costs in the production process. Simultaneously, the system ensures efficient separation in the acetone distillation process by precisely controlling the temperature and heat supply of the distillation column, improving the purity and yield of the acetone product, enhancing its market competitiveness, and bringing greater economic benefits to the enterprise. At the same time, reducing energy consumption also reduces carbon emissions caused by energy consumption, making it more environmentally friendly and in line with the development trend of green chemical production.

[0032] The above description is merely an embodiment of this utility model and is not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this utility model should be included within the scope of the claims of this utility model.

Claims

1. An acetone distillation system, characterized in that, It includes a distillation column (1), a first reboiler (2) and a second reboiler (3). The first circulation outlet of the distillation column (1) is connected to the first inlet of the first reboiler (2), the first outlet of the first reboiler (2) is connected to the first circulation inlet of the distillation column (1), the second circulation outlet of the distillation column (1) is connected to the first inlet of the second reboiler (3), and the first outlet of the second reboiler (3) is connected to the second circulation inlet of the distillation column (1). The first reboiler (2) has a heat source (4) connected to its second inlet, a second outlet of the first reboiler (2) connected to an exhaust unit, a second inlet of the second reboiler (3) connected to the gas phase outlet of the dehydrogenation tower (5), and a second outlet of the second reboiler (3) connected to the reflux tank (6) of the dehydrogenation tower (5).

2. The acetone distillation system according to claim 1, characterized in that, A circulation pump (8) is provided on the pipeline connecting the second circulation outlet of the distillation column (1) and the first inlet of the second reboiler (3). The inlet of the circulation pump (8) is connected to the second circulation outlet of the distillation column (1), and the outlet of the circulation pump (8) is connected to the first inlet of the second reboiler (3).

3. The acetone distillation system according to claim 1, characterized in that, A first valve (9) is provided on the pipeline connecting the first outlet of the second reboiler (3) to the second circulation inlet of the distillation column (1).

4. The acetone distillation system according to claim 1, characterized in that, A second valve (10) is provided on the pipeline through which the heat source (4) enters the second inlet of the first reboiler (2).

5. The acetone distillation system according to claim 1, characterized in that, A third valve (11) is provided on the pipeline connecting the second inlet of the second reboiler (3) to the gas phase outlet of the dehydrogenation tower (5).

6. The acetone distillation system according to claim 1, characterized in that, A fourth valve (12) is provided on the pipeline connecting the second outlet of the second reboiler (3) to the reflux tank (6) of the dehydrogenation tower (5).

7. The acetone distillation system according to any one of claims 1 to 6, characterized in that, The bottom temperature of the distillation column (1) is controlled at 102℃.

8. The acetone distillation system according to any one of claims 1 to 6, characterized in that, Temperature sensors are respectively installed at the first outlet of the first reboiler (2) and the first outlet of the second reboiler (3).

9. The acetone distillation system according to any one of claims 1 to 6, characterized in that, The first reboiler (2) and the second reboiler (3) are shell-and-tube heat exchangers.

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