阅读说明：本技术 高纯氯气的连续化生产工艺 (Continuous production process of high-purity chlorine ) 是由 曾令军 汪正宏 阳辉 曾令霞 于 2020-06-30 设计创作，主要内容包括：本发明提供了一种高纯氯气的连续化生产工艺,所述连续化生产工艺的步骤包括：步骤S1,将从工业液氯罐的液相空间阀出来的液氯通入气化装置,在第一温度下气化,得到气化后的氮气；步骤S2,将步骤S1中得到的所述氮气通入吸附装置,通过复配吸附剂的吸附后,得到含水量小于或者等于0.3ppmv的粗品高纯氯气；步骤S3,将步骤S2中得到的所述粗品高纯氯气通入一级精馏装置,在第一压力下,精馏脱除所述粗品高纯氯气中的重组分杂质,得到一级高纯氯气；步骤S4,将步骤S3中得到的所述一级高纯氯气通入二级精馏装置,在第二压力下,精馏脱除所述一级高纯氯气中的轻组分杂质,得到二级高纯氯气。本发明通过优化高纯氯气的生产工艺,解决了传统高纯氯气生产工艺中产量低的技术问题。(The invention provides a continuous production process of high-purity chlorine, which comprises the following steps: step S1, introducing liquid chlorine from a liquid phase space valve of an industrial liquid chlorine tank into a gasification device, and gasifying at a first temperature to obtain gasified nitrogen; step S2, introducing the nitrogen obtained in the step S1 into an adsorption device, and adsorbing by a compound adsorbent to obtain crude high-purity chlorine with the water content of less than or equal to 0.3 ppmv; step S3, introducing the crude high-purity chlorine obtained in the step S2 into a primary rectifying device, and rectifying and removing heavy component impurities in the crude high-purity chlorine under a first pressure to obtain primary high-purity chlorine; and step S4, introducing the primary high-purity chlorine gas obtained in the step S3 into a secondary rectification device, and rectifying and removing light component impurities in the primary high-purity chlorine gas under a second pressure to obtain secondary high-purity chlorine gas. The invention solves the technical problem of low yield in the traditional high-purity chlorine production process by optimizing the high-purity chlorine production process.)

1. A continuous production process of high-purity chlorine gas is characterized by comprising the following steps:

step S1, introducing liquid chlorine from a liquid phase space valve of an industrial liquid chlorine tank into a gasification device, and gasifying at a first temperature to obtain gasified nitrogen;

step S2, introducing the nitrogen obtained in the step S1 into an adsorption device, and adsorbing by a compound adsorbent to obtain crude high-purity chlorine with the water content of less than or equal to 0.3 ppmv;

step S3, introducing the crude high-purity chlorine obtained in the step S2 into a primary rectifying device, and rectifying and removing heavy component impurities in the crude high-purity chlorine under a first pressure to obtain primary high-purity chlorine;

and step S4, introducing the primary high-purity chlorine gas obtained in the step S3 into a secondary rectification device, and rectifying and removing light component impurities in the primary high-purity chlorine gas under a second pressure to obtain secondary high-purity chlorine gas.

2. The continuous process for producing high purity chlorine gas of claim 1, wherein the first temperature is in the range of 20 ℃ to 60 ℃.

3. The continuous process for producing high purity chlorine gas of claim 1, wherein the built adsorbent is a built adsorbent of a molecular sieve and activated alumina.

4. The continuous production process of high purity chlorine gas according to claim 3, wherein the mass fraction ratio of the molecular sieve to the activated alumina is 4:6 to 7: 3.

5. The continuous process for producing high purity chlorine gas of claim 1, wherein the first pressure is in the range of 0.6 to 0.8 MPa.

6. The continuous process for producing high purity chlorine gas of claim 5, wherein the second pressure is in the range of 0.4 to 0.6 MPa.

7. The continuous process for the production of high purity chlorine according to any of claims 1 to 6, wherein the height of the first rectification unit is 10 to 14 meters; and/or the presence of a gas in the gas,

the height of the second rectifying device is 10-14 m.

8. The continuous production process of high purity chlorine gas as claimed in any one of claims 1 to 6, wherein the adsorption unit comprises a use tank and a regeneration tank connected in parallel with the gas circuit between the gasification unit and the primary rectification unit.

9. The continuous production process of high-purity chlorine gas according to any one of claims 1 to 6, wherein the first rectification device comprises a first refrigerating unit and a first heating element, and the first refrigerating unit is arranged at the top of the first rectification device; the first heating device is additionally arranged at the bottom of the first rectifying device; and/or the presence of a gas in the gas,

the second rectifying device comprises a second refrigerating unit and a second heating element, the second refrigerating unit is arranged at the top of the second rectifying device, and the second heating element is arranged at the bottom of the second rectifying device.

10. The continuous process for the production of high purity chlorine of any of claims 1 to 6, further comprising:

step S5, bottling the secondary high-purity chlorine gas obtained in the step S4 by a compression canning system to obtain bottled high-purity liquid nitrogen;

step S6, introducing heavy component impurities removed by the primary rectifying device into a tail gas treatment device, and treating with alkali liquor;

and step S7, introducing the light component impurities removed by the secondary rectification device into a tail gas treatment device, and treating with alkali liquor.

Technical Field

The invention relates to the technical field of preparation of high-purity gas, in particular to a continuous production process of high-purity chlorine.

Background

Chlorine is one of the main products in the chlor-alkali industry, and is a strong oxidant and a chlorinating agent. The high-purity chlorine gas is high-purity gas obtained by purifying industrial liquid chlorine and is used as standard gas and correction gas; in addition, the high-purity chlorine can also be applied to the fields of microelectronics, optical fiber cables, high-temperature superconductivity and high-performance alloy smelting, and the like, and the advanced scientific and technological fields of related industry, basic scientific research and the like.

For a long time, high-purity chlorine in China always depends on import, and the purity of the high-purity chlorine produced by an adsorption purification method in China only exists in 80-90 years, and can reach 99.996%. The adsorption method for preparing high-purity chlorine needs to remove impurities in industrial chlorine deeply, and the impurities comprise water, oxygen, nitrogen, carbon dioxide, carbon monoxide, hydrogen, methane and other gases. The adsorption method is to remove carbon dioxide, hydrocarbons and metal ions thereof by adopting chemically treated zeolite adsorption, remove water by using a drying agent and zeolite secondary adsorption, condense and separate low-boiling-point impurities, and obtain high-purity chlorine by low-temperature bottling. The preparation of the high-purity chlorine prepared by the adsorption method needs to prepare a drying agent and an adsorbent which are not corroded by the chlorine and do not cause chlorination reaction, and select proper process conditions for drying, adsorption, regeneration and condensation, and the like, which are the problems of great technical difficulty and a lot of research contents.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a continuous production process of high-purity chlorine, which aims to solve the technical problem of low yield of the traditional high-purity chlorine production process in the related technology.

The invention provides a continuous production process of high-purity chlorine, which comprises the following steps:

step S1, introducing liquid chlorine from a liquid phase space valve of an industrial liquid chlorine tank into a gasification device, and gasifying at a first temperature to obtain gasified nitrogen;

step S2, introducing the nitrogen obtained in the step S1 into an adsorption device, and adsorbing by a compound adsorbent to obtain crude high-purity chlorine with the water content of less than or equal to 0.3 ppmv;

step S3, introducing the crude high-purity chlorine obtained in the step S2 into a primary rectifying device, and rectifying and removing heavy component impurities in the crude high-purity chlorine under a first pressure to obtain primary high-purity chlorine;

and step S4, introducing the primary high-purity chlorine gas obtained in the step S3 into a secondary rectification device, and rectifying and removing light component impurities in the primary high-purity chlorine gas under a second pressure to obtain secondary high-purity chlorine gas.

Optionally, the first temperature is in a range of 20-60 ℃.

Optionally, the built adsorbent is a built combined adsorbent of a molecular sieve and activated alumina.

Optionally, the mass fraction ratio of the molecular sieve to the activated alumina is 4:6 to 7: 3.

Optionally, the first pressure is 0.6 to 0.8 MPa.

Optionally, the second pressure is 0.4-0.6 MPa.

Optionally, the height of the first rectifying device is 10-14 m; and/or the presence of a gas in the gas,

the height of the second rectifying device is 10-14 m.

Optionally, the adsorption device comprises a use tank and a regeneration tank which are connected in parallel between the gasification device and the primary rectification device through gas circuits.

Optionally, the first rectification device comprises a first refrigerating unit and a first heating element, and the first refrigerating unit is arranged at the top of the first rectification device; the first heating device is additionally arranged at the bottom of the first rectifying device; and/or the presence of a gas in the gas,

the second rectifying device comprises a second refrigerating unit and a second heating element, the second refrigerating unit is arranged at the top of the second rectifying device, and the second heating element is arranged at the bottom of the second rectifying device.

Optionally, the continuous production process further comprises:

step S5, bottling the secondary high-purity chlorine gas obtained in the step S4 by a compression canning system to obtain bottled high-purity liquid nitrogen;

step S6, introducing heavy component impurities removed by the primary rectifying device into a tail gas treatment device, and treating with alkali liquor;

and step S7, introducing the light component impurities removed by the secondary rectification device into a tail gas treatment device, and treating with alkali liquor.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a continuous production process of high-purity chlorine, which takes industrial liquid chlorine as an initial raw material and obtains the high-purity chlorine meeting the index through the processes of gasification, single-stage adsorption, secondary rectification and the like, the whole process is simple and easy to operate, and the continuous industrial production of the high-purity chlorine can be realized; the pollution source in the production process is less, and the obtained product has high quality; the water content of the obtained high-purity chlorine gas is lower than 0.3ppmv, and the purity reaches 99.999 percent.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly apparent, the technical solutions of the present invention are further described below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

At present, no formal high-purity chlorine manufacturers exist in China in the related technology, only the research center of special gas of the Ministry of Dali Guangdong has a small amount of production technology for intermittently preparing high-purity chlorine by an adsorption method, and the yield is basically 5 tons/year. The China gas Association has a large market for the use of special gas, the annual usage amount is about 300 tons, and the total sales of foreign famous gas sellers such as Prikex, Linde gas, air products company and French liquefied air group in China can reach 300 tons per year. Thus, the China market for high purity chlorine is basically monopolized by foreign manufacturers. Based on the technical scheme, the invention provides a continuous production process of high-purity chlorine, and realizes a production line of high-purity chlorine capable of producing 1000 tons per year.

Based on the above, the invention provides a continuous production process of high-purity chlorine gas, which comprises the following steps:

step S1, introducing liquid chlorine from a liquid phase space valve of an industrial liquid chlorine tank into a gasification device, and gasifying at a first temperature to obtain gasified nitrogen;

step S2, introducing the nitrogen obtained in the step S1 into an adsorption device, and adsorbing by a compound adsorbent to obtain crude high-purity chlorine with the water content of less than or equal to 0.3 ppmv;

step S3, introducing the crude high-purity chlorine obtained in the step S2 into a primary rectifying device, and rectifying and removing heavy component impurities in the crude high-purity chlorine under a first pressure to obtain primary high-purity chlorine;

and step S4, introducing the primary high-purity chlorine gas obtained in the step S3 into a secondary rectification device, and rectifying and removing light component impurities in the primary high-purity chlorine gas under a second pressure to obtain secondary high-purity chlorine gas.

Optionally, the first temperature is in a range of 20-60 ℃. For example, but not limited to, the first temperature is in the range of 31-40 ℃.

Optionally, the built adsorbent is a built combined adsorbent of a molecular sieve and activated alumina.

Optionally, the mass fraction ratio of the molecular sieve to the activated alumina is 4:6 to 7: 3. For example, but not limiting of, the ratio of the mass fractions of the molecular sieve and the activated alumina is 6: 4.

Optionally, the first pressure is 0.6 to 0.8 MPa.

Optionally, the second pressure is 0.4-0.6 MPa.

Optionally, the height of the first rectifying device is 10-14 m; and/or the presence of a gas in the gas,

the height of the second rectifying device is 10-14 m.

Optionally, the adsorption device comprises a use tank and a regeneration tank which are connected in parallel between the gasification device and the primary rectification device through gas circuits.

Optionally, the first rectification device comprises a first refrigerating unit and a first heating element, and the first refrigerating unit is arranged at the top of the first rectification device; the first heating device is additionally arranged at the bottom of the first rectifying device; and/or the presence of a gas in the gas,

the second rectifying device comprises a second refrigerating unit and a second heating element, the second refrigerating unit is arranged at the top of the second rectifying device, and the second heating element is arranged at the bottom of the second rectifying device.

Optionally, the continuous production process further comprises:

step S5, bottling the secondary high-purity chlorine gas obtained in the step S4 by a compression canning system to obtain bottled high-purity liquid nitrogen;

step S6, introducing heavy component impurities removed by the primary rectifying device into a tail gas treatment device, and treating with alkali liquor;

and step S7, introducing the light component impurities removed by the secondary rectification device into a tail gas treatment device, and treating with alkali liquor.

The embodiment of the invention provides a continuous production process of high-purity chlorine, which takes industrial liquid chlorine as an initial raw material and obtains the high-purity chlorine meeting the index through the processes of gasification, single-stage adsorption, secondary rectification and the like, the whole process is simple and easy to operate, and the continuous industrial production of the high-purity chlorine can be realized; the pollution source in the production process is less, and the obtained product has high quality; the water content of the obtained high-purity chlorine gas is lower than 0.3ppmv, and the purity reaches 99.999 percent.

Specifically, for the gasification process, in order to improve the mass transfer driving force of gas in the single-stage adsorption process and the two-stage rectification process, the temperature of the gasification process is set. Specifically, when the first temperature is too low, the feeding speed of industrial liquid chlorine is slow, the mass transfer driving force is insufficient, and the yield of the produced high-purity chlorine gas is low; when the first temperature is too high, the pressure in the rectification process is also higher, the relative volatilization of light component impurities is reduced due to the too high rectification pressure, the rectification effect is worsened, the yield of high-purity chlorine is reduced, and the safety risk in the rectification process is also improved due to the too high rectification pressure. Therefore, in the embodiment of the invention, a large number of experiments prove that when the first temperature is 20-60 ℃, a product with qualified product quality can be obtained, and the yield of high-purity chlorine gas is improved.

Specifically, GB5138-2016 states that the mass fraction of water in qualified industrial liquid chlorine products is less than or equal to 0.04% (i.e., the volume fraction is about 1600ppmv), and the water content of high-purity chlorine gas is less than 0.3ppmv, so that a large amount of water needs to be removed in the production process from industrial liquid chlorine to high-purity liquid chlorine. Therefore, for the single-stage adsorption process, in order to remove the moisture in the industrial liquid chlorine to the maximum extent, a compound adsorbent is designed (namely, the molecular sieve and the activated alumina are compounded according to the mass fraction of 4: 6-7: 3). In addition, in the embodiment of the invention, the single-stage adsorption of the high-purity chlorine can be realized by the compound adsorbent, the multi-stage physical adsorption drying in the traditional process is avoided, the simplification of the process is realized, and the effect is excellent.

Specifically, for the secondary rectification process, in order to remove impurities in the chlorine gas with low water content to the maximum extent and reduce the pressure in the rectification process, a secondary distillation process for removing heavy component impurities and then removing light component impurities is designed, so that the pressure of the high-purity chlorine gas after rectification can be reduced (lower than the gasification pressure of GB11984-2008 & ltchlorine safety code & gt, which is 1.0MPa), and the pressure value of the high-purity chlorine gas discharged from a distillation device can meet the national standard; the impurity removal operation of removing the heavy component impurities first and then removing the light component impurities in the embodiment of the invention also avoids the use of a diaphragm compressor in the traditional impurity removal process (removing the light component impurities first and then removing the heavy component impurities), and reduces the product pollution path caused by the diaphragm rupture of the diaphragm compressor.

To more clearly illustrate the technical effects of the continuous production process of high purity chlorine gas proposed by the present invention, the present invention provides the following data for the examples. It should be understood that the data set forth in the following examples are merely intended to better illustrate the technical effect of the continuous process for the production of high purity chlorine gas as set forth in the present invention and are not to be construed as being equivalent to all experimental data.