A rectifying device for chemical synthesis process

Abstract

This utility model relates to the field of chemical distillation technology, and more particularly to a distillation apparatus for chemical synthesis processes, including a distillation column, a condenser connected to the top of the distillation column, and a reboiler connected to the bottom of the distillation column. It also includes a first heat exchange unit and a second heat exchange unit. The first heat exchange unit is used to partially cool and condense the rising gaseous material in the distillation column, and the second heat exchange unit is used to heat the liquid phase located above the second heat exchange unit in the distillation column. This utility model utilizes the heat from the high-temperature region at the bottom of the distillation column through the second heat exchange unit to heat the liquid above it, reducing the heat load on the reboiler at the bottom of the column. By using the first heat exchange unit to cool and condense the rising gaseous phase in the distillation section, the heat load on the condenser at the top of the distillation column is reduced, thus reducing cold energy consumption, optimizing the reflux ratio in the distillation process, and avoiding additional energy consumption caused by a high reflux ratio.

Description

Technical Field

[0001] This utility model relates to the field of chemical distillation technology, and in particular to a distillation apparatus for chemical synthesis processes. Background Technology

[0002] In the chemical production field, distillation, as an important separation technology, is widely used in industries such as petrochemicals, fine chemicals, and pharmaceuticals to separate and purify components in mixtures, which is crucial for ensuring product quality and improving raw material utilization. With the continuous development of the chemical industry, higher requirements are being placed on the efficiency, energy consumption, and product quality of the distillation process.

[0003] Traditional distillation processes mainly rely on the bottom reboiler to provide heat to vaporize the material and the top condenser to provide cooling energy to condense the vapor. However, existing distillation technologies have many problems: First, energy consumption is too high. The bottom reboiler needs to consume a lot of heat energy to vaporize the material, and the top condenser also needs to consume a lot of cooling energy to condense the vapor. At the same time, in order to ensure the separation effect, the high reflux ratio further aggravates energy consumption, resulting in a significant increase in production costs.

[0004] Based on the above situation, it is necessary to design a distillation device for chemical synthesis processes to solve the above problems. Utility Model Content

[0005] This invention provides a distillation apparatus for chemical synthesis processes to solve the problem of high energy consumption during heating and condensation in the prior art.

[0006] The technical problem solved by this utility model is achieved by the following technical solution:

[0007] A distillation apparatus for chemical synthesis processes includes a distillation column, a condenser connected to the top of the distillation column, and a reboiler connected to the bottom of the distillation column. It also includes a first heat exchange unit and a second heat exchange unit. The first heat exchange unit is used to partially cool and condense the rising gaseous material in the distillation column, and the second heat exchange unit is used to heat the liquid phase located above the second heat exchange unit in the distillation column. The synergistic effect of the first and second heat exchange units optimizes the gas-liquid distribution and heat distribution within the distillation column, reducing the heat load on the reboiler at the bottom of the column.

[0008] Preferably, the first heat exchange unit includes a condenser and a cooling tank for holding coolant. The condenser is provided with refrigeration pipes connected to the cooling tank at both ends. The input end and output end of the condenser are respectively provided with a gas phase discharge pipe for receiving gaseous material in the distillation column and a liquid phase discharge pipe for returning condensed liquid material to the distillation column.

[0009] Preferably, the second heat exchange unit includes a heating box and a circulation pipe disposed in the heating box. The input end and the output end of the circulation pipe are respectively connected to the distillation column located above the second heat exchange unit and the bottom box of the distillation column.

[0010] Preferably, the portion of the refrigeration pipe located inside the condenser and the portion of the circulation pipe located inside the heating chamber both have a meandering structure.

[0011] Preferably, the gas phase discharge pipe is provided with a first regulating valve for controlling the gas phase flow rate, and the liquid phase return pipe is provided with a second regulating valve for controlling the return liquid flow rate.

[0012] Preferably, the heating box is connected to the bottom of the distillation column via a reflux pipe, and a pump body is provided on the reflux pipe.

[0013] The beneficial effects of this invention are as follows: the second heat exchange unit uses the heat from the high-temperature zone at the bottom of the distillation column to heat the liquid above it, reducing the heat load on the reboiler at the bottom of the column; the first heat exchange unit uses the heat exchange unit to cool and condense the rising gas phase in the distillation section, reducing the heat load on the condenser at the top of the distillation column, reducing cold energy consumption, optimizing the reflux ratio in the distillation process, and avoiding additional energy consumption caused by a high reflux ratio. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the isometric structure provided by this utility model;

[0016] Figure 2 A cross-sectional structural schematic diagram provided for this utility model;

[0017] Figure 3 A partial structural schematic diagram of the first heat exchange unit provided by this utility model.

[0018] In the diagram, 1 is the distillation column; 11 is the condenser; 12 is the reboiler; 2 is the first heat exchange unit; 21 is the condenser box; 22 is the cooling box; 23 is the refrigeration pipe; 24 is the gas phase discharge pipe; 25 is the liquid phase discharge pipe; 3 is the second heat exchange unit; 31 is the heating box; 32 is the circulation pipe; 4 is the first regulating valve; 5 is the second regulating valve; 6 is the reflux pipe; and 61 is the pump body. Detailed Implementation

[0019] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the following description, in conjunction with specific illustrations, further elaborates on this utility model.

[0020] Reference Figures 1-3 As shown, a distillation apparatus for chemical synthesis includes a distillation column 1. A condenser 11 is connected to the top of the distillation column 1, and a reboiler 12 is connected to the bottom of the distillation column 1. The reboiler 12 is used to heat the liquid at the bottom of the column, causing it to partially vaporize and generate rising steam, which provides heat and gas-phase power for the distillation process. The condenser 11 is installed at the top of the distillation column 1 to cool and condense the top steam into liquid. Part of the condensate is returned to the top of the column as reflux liquid to maintain the gas-liquid balance and mass transfer process in the column; the remainder is collected as the top product. The apparatus also includes a first heat exchange unit 2 for partially cooling and condensing the rising gas phase material in the distillation column 1, and a second heat exchange unit 3 for cooling and condensing the liquid phase located above the second heat exchange unit 3 in the distillation column 1. The second heat exchange unit 3 optimizes the gas-liquid distribution and heat distribution within the distillation column 1 through the synergistic effect of the first heat exchange unit 2 and the second heat exchange unit 3. This reduces the heat load on the reboiler 12 at the bottom of the column. The second heat exchange unit 3 heats the liquid phase above the reboiler 12, further reducing the heat load on the reboiler 12. The first heat exchange unit 2 cools and condenses the rising gas phase in the rectification section, reducing the heat load on the condenser 11 at the top of the distillation column 1 and reducing cold energy consumption. The first heat exchange unit 2 increases the liquid phase load in the rectification section, and the second heat exchange unit 3 increases the gas phase load in the corresponding area. The synergistic effect of the two optimizes the gas-liquid distribution within the distillation column 1, making the gas-liquid contact within the column more complete and the mass transfer process more efficient.

[0021] Specifically, the first heat exchange unit 2 includes a condenser 21 and a cooling tank 22 for holding coolant. The condenser 21 has internal cooling pipes 23 connected to the cooling tank 22 at both ends. The condenser 21 has a gas discharge pipe 24 for receiving gaseous material from the distillation column 1 and a liquid discharge pipe 25 for returning condensed liquid material to the distillation column 1, respectively. The cooling tank 22 has a cooler 26 for cooling the coolant; this can be a semiconductor cooler, etc. Furthermore, to ensure the coolant circulates within the cooling tank 22 and the cooling tank... The cooling pipe 23 can also be equipped with a circulating pump to pump the coolant. The gas phase inside the distillation column 1 enters the condenser 11 for condensation, while a portion enters the condenser box 21 through the gas phase outlet pipe 24. After contacting the condenser tube in the condenser box 21, it condenses into liquid phase and flows back into the distillation column 1 through the liquid phase outlet pipe 25. The gas phase in the top of the distillation column 1 is pre-cooled through the first heat exchange unit 2, which reduces the gas phase flow rate entering the top condenser 11. The reduction in gas phase flow rate means that the heat that the top condenser 11 needs to handle is reduced, that is, the heat load is reduced.

[0022] The second heat exchange unit 3 includes a heating box 31 and a circulation pipe 32 located inside the heating box 31. The input end and output end of the circulation pipe 32 are connected to the distillation column 1 located above the second heat exchange unit 3 and the bottom box of the distillation column 1, respectively. The liquid phase after being condensed and refluxed by the condenser 11 flows back to the upper part of the distillation column 1. Therefore, the liquid phase temperature at the upper part of the distillation column 1 is lower than the liquid phase temperature at the lower part of the distillation column 1. The slightly lower liquid phase temperature enters the heating box 31 through the circulation pipe 32 for heating, and can also allow some of the liquid phase to be re-vaporized and enter the distillation column 1, reducing the load on the reboiler 12 at the bottom of the distillation column 1, thereby reducing the energy consumption required by the reboiler 12.

[0023] Reference Figure 2 As shown, the heating box 31 is further connected to the bottom of the distillation column 1 through the reflux pipe 6, and the reflux pipe 6 is equipped with a pump body 61. The pump body 61 can draw the hot liquid phase at the bottom of the distillation column 1 into the heating box 31 to heat the cold liquid phase in the circulation pipe 32, and reuse the heat. There is no need to set up a new heating source, which is more energy-efficient.

[0024] Reference Figure 2 As shown, the portion of the refrigeration pipe 23 located in the condenser 21 and the portion of the circulation pipe 32 located in the heating chamber 31 are both meandering structures. The meandering structure can adopt spiral, "U" shape or other shapes to increase the contact area between the refrigeration pipe 23 and the coolant and between the circulation pipe 32 and the higher temperature liquid phase, prolong the residence time of the liquid phase in the heat exchange unit, make the heat transfer more complete, and further improve the heat exchange efficiency of the entire distillation device.

[0025] Reference Figure 2 As shown, furthermore, a first regulating valve 4 for controlling the gas flow rate is installed on the gas phase outlet pipe 24, and a second regulating valve 5 for controlling the reflux liquid flow rate is installed on the liquid phase outlet pipe 25. Through the first regulating valve 4 on the gas phase outlet pipe 24, the gas flow rate entering the first heat exchange unit 2 can be precisely controlled according to the actual needs of the distillation process. For example, when it is necessary to enhance the regulating effect of the first heat exchange unit 2 on the gas-liquid distribution in the distillation section, the opening of the first regulating valve 4 can be appropriately increased to allow more gas phase to enter the intermediate condenser 11 for cooling and condensation; conversely, the opening can be decreased. Through the second regulating valve 5 on the liquid phase outlet pipe 25, the amount of liquid refluxed into the distillation column 1 can be precisely controlled according to the operating requirements of the distillation column 1. When it is necessary to improve the purity of the top product, the opening of the second regulating valve 5 can be appropriately increased to increase the reflux liquid volume; when it is necessary to improve the column's processing capacity, the opening can be decreased.

[0026] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A rectification device for chemical synthesis process, comprising a rectification tower (1), a condenser (11) connected above the rectification tower (1), and a reboiler (12) connected below the rectification tower (1), characterized in that, It also includes a first heat exchange unit (2) and a second heat exchange unit (3); the first heat exchange unit (2) is used to partially cool and condense the rising gaseous material in the distillation column (1), and the second heat exchange unit (3) is used to heat the liquid phase located above the second heat exchange unit (3) in the distillation column (1). The gas-liquid distribution and heat distribution in the distillation column (1) are optimized through the synergistic effect of the first heat exchange unit (2) and the second heat exchange unit (3), thereby reducing the heat load of the reboiler (12) at the bottom of the column.

2. The rectification device for chemical synthesis process according to claim 1, characterized in that, The first heat exchange unit (2) includes a condenser (21) and a cooling tank (22) for holding coolant. The condenser (21) is provided with a refrigeration pipe (23) with both ends connected to the cooling tank (22). The input end and output end of the condenser (21) are respectively provided with a gas phase discharge pipe (24) for receiving gas phase material in the distillation column (1) and a liquid phase discharge pipe (25) for returning the condensed liquid phase material to the distillation column (1). The second heat exchange unit (3) includes a heating box (31) and a circulation pipe (32) provided in the heating box (31). The input end and output end of the circulation pipe (32) are respectively connected to the distillation column (1) located above the second heat exchange unit (3) and the bottom box of the distillation column (1).

3. The rectification device for chemical synthesis process according to claim 2, characterized in that, The portion of the refrigeration pipe (23) located inside the condenser (21) and the portion of the circulation pipe (32) located inside the heater (31) are both meandering structures.

4. The rectification device for chemical synthesis process according to claim 2, characterized in that, The gas phase discharge pipe (24) is equipped with a first regulating valve (4) for controlling the gas phase flow rate, and the liquid phase discharge pipe (25) is equipped with a second regulating valve (5) for controlling the reflux liquid flow rate.

5. The rectification device for chemical synthesis process according to claim 2, characterized in that, The heating box (31) is connected to the bottom of the distillation column (1) through the reflux pipe (6), and the reflux pipe (6) is equipped with a pump body (61).

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