Ethylene amine product separation system and method

Abstract

The invention relates to the technical field of separation, in particular to an ethylenediamine product separation system and method. Side extraction pipelines are additionally arranged on a diethylenetriamine rectifying tower, an aminoethyl piperazine rectifying tower and a hydroxyethyl ethylenediamine rectifying tower; the rectifying tower I is provided with a diethylenetriamine product side extraction pipeline between the first layer of packed tower and the second layer of packed tower; the rectifying tower II is provided with an aminoethyl piperazine side extraction pipeline between the first layer of packed tower and the second layer of packed tower; and the rectifying tower III is provided with a hydroxyethyl ethylenediamine side extraction pipeline between the first layer of packed tower and the second layer of packed tower. According to the invention, the side extraction pipelines are added on the diethylenetriamine rectifying tower, the aminoethyl piperazine rectifying tower and the hydroxyethyl ethylenediamine rectifying tower, the products are extracted through the side extraction pipelines, and the tower top pipelines are all subjected to reflux, so that the product quality is improved, and the income is increased.

Description

Technical Field

[0001] The present invention relates to the field of separation technology, and in particular to an ethyleneamine product separation system and method. Background Art

[0002] Ethyleneamines is a general term for ethyleneamine products, including acyclic polymers of ethylenediamine, such as aminoethylpiperazine, diethylenetriamine and hydroxyethylethylenediamine. As important chemical raw materials, these products are widely used in the fields of petroleum, light industry, pesticides, papermaking, etc.

[0003] In the traditional separation of ethyleneamine products, the products of aminoethylpiperazine, diethylenetriamine and hydroxyethylethylenediamine are extracted through the top pipeline of the tower. The top cooler is cooled by cooling water alone, resulting in unstable product quality and high energy consumption. Summary of the invention

[0004] The object of the present invention is to provide an ethyleneamine product separation system and method, by adding a side sampling pipeline to a diethylenetriamine, aminoethylpiperazine, or hydroxyethylethylenediamine distillation tower, extracting the above products through the side sampling pipeline, and refluxing all the tower top pipelines to improve product quality.

[0005] In order to achieve the above object, the technical solution of the present invention is as follows:

[0006] On one hand, the present invention provides an ethyleneamine product separation system, comprising a distillation tower I, a distillation tower II, a distillation tower III, a reboiler I, a reboiler II, a reboiler III, a cooler I, a cooler II, a cooler III, a reflux tank I, a reflux tank II, and a reflux tank III, wherein the distillation tower I is used to separate diethylenetriamine, and a gas phase outlet at the top of the distillation tower I sequentially passes through the cooler I and the reflux tank I to form a circulation loop, and the distillation tower I is located between the first and second packed towers and is provided with a diethylenetriamine product side sampling pipeline;

[0007] The distillation tower II is used to separate aminoethylpiperazine. The gas phase outlet at the top of the distillation tower II passes through the cooler II and the reflux tank II in sequence to form a circulation loop. The distillation tower II is located between the first and second packed towers and is provided with an aminoethylpiperazine side sampling pipeline.

[0008] The distillation tower III is used to separate hydroxyethylethylenediamine. The gas phase outlet at the top of the distillation tower III passes through the cooler III and the reflux tank III in sequence to form a circulation loop. The distillation tower III is located between the first and second packed towers and is provided with a hydroxyethylethylenediamine side sampling pipeline.

[0009] In the above technical solution, further, the liquid phase outlet at the bottom of the distillation tower I is connected to the reboiler I in one way, and is connected to the distillation tower II in the other way.

[0010] In the above technical solution, further, the liquid phase outlet at the bottom of the distillation tower II is connected to the reboiler II on one side, and is connected to the distillation tower III on the other side.

[0011] In the above technical solution, further, one way of the liquid phase outlet at the bottom of the distillation tower III is connected to the reboiler III, and the other way enters the heavy component tank area.

[0012] In the above technical solution, further, the tube passes of cooler I, cooler II and cooler III are all provided with partitions.

[0013] On the other hand, the present invention provides an ethyleneamine product separation method. The product mixture after MEA is separated from ethyleneamine by an MEA tower enters a distillation tower I for diethylenetriamine product separation. After separation at the top of the distillation tower I, the gas phase is sequentially refluxed through a cooler I and a reflux tank I. The diethylenetriamine product is extracted from a diethylenetriamine product side extraction pipeline. The liquid phase components at the bottom of the distillation tower I enter a distillation tower II for aminoethylpiperazine product separation. After separation at the top of the distillation tower II, the gas phase is sequentially refluxed through a cooler II and a reflux tank II. The aminoethylpiperazine product is extracted from the aminoethylpiperazine product side extraction pipeline. The liquid phase components at the bottom of the distillation tower II enter a distillation tower III for hydroxyethylethylenediamine product separation. After separation at the top of the distillation tower III, the gas phase is sequentially refluxed through a cooler III and a reflux tank III. The hydroxyethylethylenediamine product is extracted from the hydroxyethylethylenediamine side extraction pipeline. The liquid phase components at the bottom of the distillation tower III enter a heavy component tank area for collection.

[0014] The beneficial effects of the present invention are:

[0015] 1. In the prior art, diethylenetriamine, aminoethylpiperazine and hydroxyethylethylenediamine are extracted from the tower top pipeline, and the product quality and purity fluctuate greatly, so that the product purity does not meet the standard and the water content exceeds the standard. The present invention adds side extraction pipelines to the distillation towers of diethylenetriamine, aminoethylpiperazine and hydroxyethylethylenediamine, extracts the above products through the side extraction pipelines, and all the tower top pipelines are refluxed, thereby improving product quality and increasing revenue.

[0016] 2. The present invention provides a partition in the cooler and adopts two cooling media for secondary heat exchange, which can save 99.95 kg of standard oil per ton of product. At the same time, it can produce high-level heat source, reduce energy consumption, reduce product cost, and thus increase economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 This is a schematic diagram of the structure of the ethyleneamine product separation system of the present invention;

[0019] In the figure: 1. distillation tower I, 2. distillation tower II, 3. distillation tower III, 4. cooler I, 5. cooler II, 6. cooler III, 7. reflux tank I, 8. reflux tank II, 9. reflux tank III, 10. diethylenetriamine product side sampling pipeline, 11. aminoethylpiperazine side sampling pipeline, 12. hydroxyethylethylenediamine side sampling pipeline, 13. reboiler I, 14. reboiler II, 15. reboiler III. DETAILED DESCRIPTION

[0020] The following examples may enable those skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0021] An ethyleneamine product separation system, such as Figure 1 As shown, it includes a distillation tower Ⅰ1, a distillation tower Ⅱ2, a distillation tower Ⅲ3, a cooler Ⅰ4, a cooler Ⅱ5, a cooler Ⅲ6, a reflux tank Ⅰ7, a reflux tank Ⅱ8, a reflux tank Ⅲ9, a reboiler Ⅰ13, a reboiler Ⅱ14, and a reboiler Ⅲ15. The distillation tower Ⅰ1 is used to separate diethylenetriamine. The gas phase outlet at the top of the distillation tower Ⅰ1 passes through the cooler Ⅰ4 and the reflux tank Ⅰ7 in sequence to form a circulation loop. The distillation tower Ⅰ1 is located between the first and second layers of the packed tower and is provided with a diethylenetriamine product side sampling pipeline 10. The liquid phase outlet at the bottom of the distillation tower Ⅰ1 is connected to the reboiler Ⅰ13 on one side and to the distillation tower Ⅱ2 on the other side. The distillation tower Ⅱ2 is used to separate aminoethylpiperazine. The gas phase outlet at the top of the distillation tower Ⅱ2 passes through the cooler Ⅰ4 and the reflux tank Ⅰ7 in sequence to form a circulation loop. Cooler Ⅱ5 and reflux tank Ⅱ8 form a circulation loop, distillation tower Ⅱ2 is located between the first and second packed towers and is provided with an aminoethylpiperazine side sampling pipeline 11, the bottom liquid phase outlet of distillation tower Ⅱ2 is connected to reboiler Ⅱ14 on one way, and is connected to distillation tower Ⅲ3 on the other way; distillation tower Ⅲ3 is used to separate hydroxyethylethylenediamine, and the top gas phase outlet of distillation tower Ⅲ3 passes through cooler Ⅲ6 and reflux tank Ⅲ9 in turn to form a circulation loop, distillation tower Ⅲ3 is located between the first and second packed towers and is provided with a hydroxyethylethylenediamine side sampling pipeline 12, the bottom liquid phase outlet of distillation tower Ⅲ3 is connected to reboiler Ⅲ15 on one way, and enters the heavy component tank area on the other way; cooler Ⅰ4, cooler Ⅱ5, cooler Ⅲ6 pipe lines are all provided with partitions.

[0022] The method for separating ethyleneamine products by using the above separation system is as follows: the product mixture after ethyleneamine is separated from MEA by the MEA tower enters the distillation tower Ⅰ1 for separation of diethylenetriamine products; the gas phase after separation at the top of the distillation tower Ⅰ1 is completely refluxed through the cooler Ⅰ4 and the reflux tank Ⅰ7 in sequence; the diethylenetriamine product is produced from the diethylenetriamine product side production pipeline 10; the liquid phase component at the bottom of the distillation tower Ⅰ1 enters the distillation tower Ⅱ2 for separation of aminoethylpiperazine products; the top of the distillation tower Ⅱ2 is separated The gas phase after separation is fully refluxed through cooler Ⅱ5 and reflux tank Ⅱ8 in turn, and the aminoethyl piperazine product is produced from the aminoethyl piperazine product side production pipeline; the liquid phase components at the bottom of the distillation tower Ⅱ2 enter the distillation tower Ⅲ3 to separate the hydroxyethyl ethylenediamine product, and the gas phase after separation at the top of the distillation tower Ⅲ3 is fully refluxed through cooler Ⅲ6 and reflux tank Ⅲ9 in turn, and the hydroxyethyl ethylenediamine product is produced from the hydroxyethyl ethylenediamine side production pipeline 12, and the liquid phase components at the bottom of the distillation tower Ⅲ3 enter the heavy component tank area for collection;

[0023] Partitions are added to the tubes of cooler I4, cooler II5 and cooler III6, and 70°C hot water is introduced into the upper part. After heat exchange with the gas phase components at the top of the tower, 95°C hot water is produced and sent to the steam generator to produce steam for waste heat recovery. 31°C cooling water is introduced into the lower part of the partition to further cool the gas phase components at the top of the tower to the target temperature.

[0024] The ethyleneamine product separation method of the present invention can save 60% of cooling water usage, and the product purity reaches 99.8%.

[0025] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the implementation methods. The protection scope of the present invention shall be subject to the scope defined in the claims. Other different forms of changes or modifications may be made based on the above description. Obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. An ethyleneamine product separation system, comprising a distillation tower I, a distillation tower II, a distillation tower III, a reboiler I, a reboiler II, a reboiler III, a cooler I, a cooler II, a cooler III, a reflux tank I, a reflux tank II, and a reflux tank III, characterized in that: The distillation tower I is used to separate diethylenetriamine. The gas phase outlet at the top of the distillation tower I passes through the cooler I and the reflux tank I in sequence to form a circulation loop. The distillation tower I is located between the first and second layers of the packed tower and is provided with a diethylenetriamine product side sampling pipeline; The distillation tower II is used to separate aminoethylpiperazine. The gas phase outlet at the top of the distillation tower II passes through the cooler II and the reflux tank II in sequence to form a circulation loop. The distillation tower II is located between the first and second packed towers and is provided with an aminoethylpiperazine side sampling pipeline. The distillation tower III is used to separate hydroxyethylethylenediamine. The gas phase outlet at the top of the distillation tower III passes through the cooler III and the reflux tank III in sequence to form a circulation loop. The distillation tower III is located between the first and second packed towers and is provided with a hydroxyethylethylenediamine side sampling pipeline.

2. The ethyleneamine product separation system according to claim 1, characterized in that: The liquid phase outlet at the bottom of the distillation tower I is connected to the reboiler I on one side, and is connected to the distillation tower II on the other side.

3. The ethyleneamine product separation system according to claim 1, characterized in that: The liquid phase outlet at the bottom of the distillation tower II is connected to the reboiler II on one side, and is connected to the distillation tower III on the other side.

4. The ethyleneamine product separation system according to claim 1, characterized in that: One of the liquid phase outlets at the bottom of the distillation tower III is connected to the reboiler III, and the other one enters the heavy component tank area.

5. The ethyleneamine product separation system according to claim 1, characterized in that: The tube paths of the cooler I, cooler II and cooler III are all provided with partitions.

6. A method for separating ethyleneamine products using the separation system according to any one of claims 1 to 5, characterized in that: The product mixture after ethyleneamine is separated from MEA by the MEA tower enters the distillation tower I for separation of diethylenetriamine product. After separation at the top of the distillation tower I, the gas phase is sequentially refluxed through the cooler I and the reflux tank I, and the diethylenetriamine product is produced from the diethylenetriamine product side production pipeline. The liquid phase component at the bottom of the distillation tower I enters the distillation tower II for separation of aminoethylpiperazine product. After separation at the top of the distillation tower II, the gas phase is sequentially refluxed through the cooler II and the reflux tank II, and the aminoethylpiperazine product is produced from the aminoethylpiperazine product side production pipeline. The liquid components at the bottom of distillation tower II enter into distillation tower III for separation of hydroxyethylethylenediamine products. After separation at the top of distillation tower III, the gas phase is fully refluxed through cooler III and reflux tank III in sequence. The hydroxyethylethylenediamine product is produced from the hydroxyethylethylenediamine side production pipeline. The liquid components at the bottom of distillation tower III enter into the heavy component tank area for collection.

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