Evaporation tower for producing isophthaloyl chloride / paraphthaloyl chloride

Abstract

According to the evaporation tower for producing isophthaloyl / paraphthaloyl chloride provided by the utility model, in a working state, an isophthaloyl / paraphthaloyl chloride solution enters a reaction liquid inlet above the evaporation tower, heat-conducting oil enters a heating jacket, and the heat of the heat-conducting oil heats the isophthaloyl / paraphthaloyl chloride solution in a spiral disc groove through the inner wall of the evaporation tower, so that the isophthaloyl / paraphthaloyl chloride is produced. Thionyl chloride and N, N-dimethylformamide in the paraphthaloyl chloride solution are evaporated into gas in the spiral disc grooves under a micro-negative pressure vacuum condition, the gas is led out from the top of the evaporation tower, finally, the purity of the paraphthaloyl / paraphthaloyl chloride solution is improved after the paraphthaloyl / paraphthaloyl chloride solution is subjected to high-temperature evaporation of the multiple layers of spiral disc grooves, and the paraphthaloyl / paraphthaloyl chloride solution is discharged from a liquid outlet below the evaporation tower. Compared with the existing conventional tower kettle type intermittent evaporation equipment, the evaporation tower provided by the utility model can perform continuous distillation, shorten the operation period, improve the production efficiency, fully utilize the waste heat of the conduction oil of the reaction kettle and improve the energy utilization rate.

Description

Technical Field

[0001] This utility model belongs to the field of chemical synthesis and relates to an evaporation tower, and more particularly to an evaporation tower for producing terephthaloyl chloride. Background Technology

[0002] The aramid industry is currently highly competitive, and the demand for isophthaloyl chloride (IPC), one of the two main monomers essential for synthesizing aramid fibers, is growing rapidly. Domestic demand for aramid fibers and their products is currently increasing at a rate of 30% annually. Therefore, reducing investment costs in upstream raw material production, and indirectly lowering production costs, has become a key economic strategy for aramid manufacturers. Given the severe homogenization in aramid production, optimizing and improving the upstream supply chain to reduce production costs is crucial for companies to improve efficiency and quality.

[0003] Currently, the preparation of terephthaloyl chloride generally adopts intermittent distillation process equipment, mainly with a kettle-tower structure, segmented purification, intermittent operation, low efficiency and large equipment footprint. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide an evaporation tower for the production of terephthaloyl chloride, so as to upgrade the distillation of terephthaloyl chloride from intermittent batch distillation to continuous distillation and improve production efficiency.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] This utility model provides an evaporation tower for producing terephthaloyl chloride, comprising:

[0007] The evaporator body has a reaction liquid inlet at the top, a liquid outlet at the bottom, and a vacuum steam outlet at the top. The interior of the evaporator body has a spiral groove with its opening facing upwards. The upper end of the spiral groove is connected to the reaction liquid inlet, and the lower end is connected to the liquid outlet.

[0008] And a heating jacket is provided on the outside of the evaporator body; a heat transfer oil outlet is provided above the heating jacket and a heat transfer oil inlet is provided below the heating jacket.

[0009] Preferably, the spiral groove is a square groove with the opening facing upwards.

[0010] Preferably, the inflection point of the spiral groove is in contact with the inner wall of the evaporation tower body.

[0011] Preferably, the inner wall of the evaporation tower body is provided with protrusions.

[0012] Preferably, the inflection point of the spiral groove contacts the protrusion.

[0013] Preferably, the protrusion is a cube protrusion, a cuboid protrusion, or a hemispherical protrusion.

[0014] Preferably, the spiral groove has 5 to 20 spiral layers.

[0015] Preferably, the thickness of the heating jacket is 70~80 mm.

[0016] Preferably, an evaporator skirt is provided at the bottom of the evaporator body.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] This invention provides an evaporation tower for producing isophthaloyl chloride. In operation, the isophthaloyl chloride solution enters the reaction liquid inlet at the top of the evaporation tower, while high-temperature heat transfer oil enters the heat transfer oil inlet below the heating jacket. After filling the heating jacket, the oil exits from the heat transfer oil outlet above the heating jacket. The heat from the high-temperature heat transfer oil heats the isophthaloyl chloride solution in the spiral groove through the inner wall of the evaporation tower. The thionyl chloride in the terephthaloyl chloride solution... N , N Dimethylformamide (DMF) is evaporated into a gas in a spiral evaporator under slight negative pressure vacuum conditions and exited from the top of the evaporation tower. Finally, the isophthaloyl / terephthaloyl chloride solution undergoes high-temperature evaporation in multiple spiral evaporator layers, resulting in increased purity, and is discharged from the liquid outlet at the bottom of the evaporation tower. Compared to existing conventional batch evaporation equipment, the evaporation tower provided by this invention can perform continuous distillation, reducing the operating cycle and improving production efficiency. Simultaneously, it can fully utilize the waste heat of the heat transfer oil in the reactor, improving energy utilization. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the evaporation tower provided by this utility model;

[0020] Among them, 1 is the evaporator body, 2 is the reaction liquid inlet, 3 is the liquid outlet, 4 is the vacuum steam outlet, 5 is the spiral groove, 6 is the heating jacket, 7 is the heat transfer oil outlet, 8 is the heat transfer oil inlet, and 9 is the evaporator skirt. Detailed Implementation

[0021] The technical solution of this utility model will be clearly and completely described below with reference to its embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0022] This utility model provides an evaporation tower for producing terephthaloyl chloride, the structural schematic diagram of which is shown below. Figure 1 As shown, it includes:

[0023] An evaporator body 1 is provided, with a reaction liquid inlet 2 at the top, a liquid outlet 3 at the bottom, and a vacuum steam outlet 4 at the top; an evaporator skirt 9 is provided at the bottom. A spiral groove 5 is provided inside the evaporator body, with the groove opening facing upwards. The upper end of the spiral groove 5 is connected to the reaction liquid inlet 2, and the lower end of the spiral groove 5 is connected to the liquid outlet 3.

[0024] And a heating jacket 6 is provided on the outside of the evaporator body 1; a heat transfer oil outlet 7 is provided above the heating jacket 6, and a heat transfer oil inlet 8 is provided below the heating jacket 6.

[0025] In this invention, the reaction liquid inlet 2 is the reaction liquid, namely, the inlet of the m / terephthaloyl chloride solution.

[0026] In this invention, the liquid outlet 3 is the outlet of the remaining liquid after the isophthaloyl chloride solution has been evaporated at high temperature.

[0027] In this invention, the vacuum vapor outlet 4 is the outlet for thionyl chloride and DMF produced after the isophthaloyl chloride solution is heated to a high temperature.

[0028] In this invention, the spiral groove 5 is a square groove with an upward opening, resembling a "slide" structure. The upper end of the spiral groove 5 is connected to the reaction liquid inlet 2, and the lower end is connected to the liquid outlet 3. The spiral groove 5 has multiple layers, the specific number of which depends on the purity requirements of iso- / terephthaloyl chloride; the more layers, the higher the purity of iso- / terephthaloyl chloride. In some specific embodiments of this invention, the spiral groove can have 5 to 20 spiral layers.

[0029] In some embodiments of this utility model, preferably, the inflection point of the spiral groove 5 at each layer of the spiral is in contact with the inner wall of the evaporation tower body 1. Preferably, the inner wall of the evaporation tower body 1 is provided with a protrusion, and the inflection point of the spiral groove contacts the protrusion to achieve a better contact effect.

[0030] In some preferred embodiments of this utility model, the protrusion is preferably a hollow structure, which is connected to the heating jacket 6 and filled with heat-conducting oil to better transfer the heat of the heat-conducting oil to the spiral groove 5, thus better utilizing the heating effect of the heat-conducting oil.

[0031] This invention does not impose any particular restrictions on the shape of the protrusion; it can be a cube protrusion, a cuboid protrusion, a hemispherical protrusion, or other shapes. Furthermore, the size of the protrusion can be freely set as needed; for example, the side length of the cube protrusion can be approximately 1500 mm; the radius of the hemispherical protrusion can be approximately 1500 mm.

[0032] As described above, a heating jacket 6 is also provided on the outer side of the evaporator tower body 1; the thickness of the heating jacket is 70~80 mm, and can be adjusted according to actual specifications and operating conditions. In this invention, a heat transfer oil outlet 7 is provided above the heating jacket 6, and a heat transfer oil inlet 8 is provided below the heating jacket 6. The temperature of the heat transfer oil is 180~200℃, preferably 190~195℃. This invention uses the high temperature of the heat transfer oil to heat the spiral groove 5 containing the isophthaloyl chloride solution inside the evaporator tower body 1, thereby causing impurities in the isophthaloyl chloride solution to evaporate, achieving the purpose of improving the purity of isophthaloyl chloride.

[0033] In some specific embodiments of this utility model, taking terephthaloyl chloride solution as the reaction liquid as an example, the working state of the evaporation tower is as follows:

[0034] The terephthaloyl chloride solution flows into the spiral groove 5 through the reaction liquid inlet 2 above the evaporator body 1. At the same time, high-temperature (180~200℃) heat transfer oil enters the heat transfer oil inlet 8 below the heating jacket 6, fills the heating jacket 6, and then exits from the heat transfer oil outlet 7 above the heating jacket 6. The heat of the heat transfer oil heats the terephthaloyl chloride solution in the spiral groove 5 through the inner wall of the evaporator body 1. Under a vacuum condition of about 90 kPa with slight negative pressure, thionyl chloride and DMF in the terephthaloyl chloride solution evaporate into gas in the spiral groove 5 and are discharged from the vacuum vapor outlet 4 at the top of the evaporator body 1. Finally, the purity of the terephthaloyl chloride solution is improved after high-temperature evaporation through multiple spiral grooves and it is discharged from the liquid outlet 3 below the evaporator body.

[0035] Compared with existing conventional batch evaporation equipment, the evaporation tower provided by this invention can perform continuous distillation, reduce the operation cycle, improve production efficiency, and make full use of the waste heat of the heat transfer oil in the reactor to improve energy utilization.

[0036] Tests have shown that the evaporation tower provided by this invention, with continuous feeding and discharging, can achieve a purity of over 99.9% for m / terephthaloyl chloride.

[0037] To further illustrate this utility model, the following embodiments provide a detailed description. The experimental materials used in the following embodiments of this utility model are all commercially available products.

[0038] Example 1

[0039] This embodiment provides an evaporation tower, the structural schematic of which is shown below. Figure 1 As shown, it includes:

[0040] An evaporator body 1 is provided, with a reaction liquid inlet 2 at the top, a liquid outlet 3 at the bottom, and a vacuum steam outlet 4 at the top. An evaporator skirt 9 is provided at the bottom. A spiral groove 5 is provided inside the evaporator body, with the groove opening facing upwards and consisting of nine spiral layers. The upper end of the spiral groove 5 is connected to the reaction liquid inlet 2, and the lower end is connected to the liquid outlet 3. The spiral groove is in contact with the inner wall of the evaporator body 1, as detailed in a partial longitudinal enlarged view.

[0041] And a heating jacket 6 is provided on the outside of the evaporator body 1; a heat transfer oil outlet 7 is provided above the heating jacket 6, and a heat transfer oil inlet 8 is provided below the heating jacket 6.

[0042] Work status:

[0043] The terephthaloyl chloride solution flows into the spiral groove 5 through the reaction liquid inlet 2 above the evaporator body 1. At the same time, high-temperature (180°C) heat transfer oil enters the heat transfer oil inlet 8 below the heating jacket 6, fills the heating jacket 6, and then exits from the heat transfer oil outlet 7 above the heating jacket 6. The heat of the heat transfer oil heats the terephthaloyl chloride solution in the spiral groove 5 through the inner wall of the evaporator body 1. Under a vacuum condition of about 90 kPa with slight negative pressure, thionyl chloride and DMF in the terephthaloyl chloride solution evaporate into gas in the spiral groove 5 and are discharged from the vacuum vapor outlet 4 at the top of the evaporator body 1. Finally, the purity of the terephthaloyl chloride solution is improved after high-temperature evaporation through multiple spiral grooves and it is discharged from the liquid outlet 3 below the evaporator body.

[0044] The evaporation tower provided in this embodiment has continuous feeding and continuous discharging. After testing, the purity of terephthaloyl chloride is 99.9%.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An evaporation tower for producing terephthaloyl chloride, characterized in that, include: The evaporator body has a reaction liquid inlet at the top, a liquid outlet at the bottom, and a vacuum steam outlet at the top. The interior of the evaporator body has a spiral groove with its opening facing upwards. The upper end of the spiral groove is connected to the reaction liquid inlet, and the lower end is connected to the liquid outlet. And a heating jacket is provided on the outside of the evaporator body; a heat transfer oil outlet is provided above the heating jacket and a heat transfer oil inlet is provided below the heating jacket.

2. The evaporation tower for the production room / terephthaloyl chloride according to claim 1, characterized in that, The inflection point of the spiral groove contacts the inner wall of the evaporation tower body.

3. The evaporation tower for the production room / terephthaloyl chloride according to claim 2, characterized in that, The spiral groove is a square groove with the opening facing upwards.

4. The evaporation tower for the production room / terephthaloyl chloride according to claim 1, characterized in that, The inner wall of the evaporator tower body is provided with protrusions.

5. The evaporation tower for the production room / terephthaloyl chloride according to claim 4, characterized in that, The inflection point of the spiral groove contacts the protrusion.

6. The evaporation tower for the production room / terephthaloyl chloride according to claim 4 or 5, characterized in that, The protrusion is a cube protrusion, a cuboid protrusion, or a hemispherical protrusion.

7. The evaporation tower for the production room / terephthaloyl chloride according to claim 1, characterized in that, The spiral groove has 5 to 20 spiral layers.

8. The evaporation tower for the production room / terephthaloyl chloride according to claim 1, characterized in that, The thickness of the heating jacket is 70~80 mm.

9. The evaporation tower for the production room / terephthaloyl chloride according to claim 1, characterized in that, An evaporator skirt is provided at the bottom of the evaporator body.

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