Production device and production method of electronic-grade chlorine

Abstract

The invention discloses a production device and a production method of electronic-grade chlorine, and the production device comprises a raw material storage tank, a gasification device, a dehydration tower, a light component removal tower, a heavy component removal tower, a compressor and a product collection bottle which are connected in sequence; the production method specifically comprises the following steps: (1) gasifying liquid chlorine; (2) removing moisture; (3) removing light component impurities; and (4) removing heavy component impurities, compressing and storing. The gasification device, the dehydration tower, the light component removal tower and the heavy component removal tower are adopted for separation and purification, metal ions, nitrogen trichloride and other chlorides in chlorine are further removed on the basis of removing water, oxygen, nitrogen and other impurities, explosion caused by long-term mixing of nitrogen trichloride and chlorine is avoided, meanwhile, the product purity is greatly improved, and the production cost is reduced. The method has the characteristics of simple process, low production cost, high product purity and the like, is easy to realize industrial production, can effectively reduce the production cost of enterprises, and greatly improves the economic benefits of the enterprises.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic industry, and more particularly to a production device and a production method of electronic grade chlorine. Background Art

[0002] Chlorine is one of the main products of the chlor-alkali industry and is a strong oxidant and chlorinating agent. High-purity chlorine is a special gas with a purity of more than 99.996%. The purity of high-purity chlorine currently used in the market generally reaches more than 99.999%, and it has extremely high requirements for the content of impurities such as moisture and metals. High-purity chlorine is mainly used in the etching process in the field of display panel and integrated circuit manufacturing and the dehydration process in the field of optical fiber manufacturing. It is an important electronic special gas and is highly indispensable.

[0003] At present, the preparation method of high-purity chlorine mainly includes electrolytic chlorine distillation purification method, industrial liquid chlorine preparation method, etc. Patent CN103626129A discloses a method for preparing electronic grade high-purity chlorine using industrial liquid chlorine as raw material, which adopts multi-stage physical drying to remove moisture, and then removes impurities such as carbon dioxide, nitrogen, and oxygen by adsorption and condensation to obtain electronic grade high-purity chlorine, which is simple to operate, short process, low production cost, and high income. Although this method removes impurities such as carbon dioxide, nitrogen, and oxygen to improve the purity of chlorine, it fails to remove metal ions and chlorides that seriously affect the use of high-purity chlorine in the electronics industry, wherein nitrogen trichloride is easily accumulated for a long time and can cause explosions, and removal treatment is urgently needed.

[0004] Therefore, how to develop a method for producing high-purity electronic-grade chlorine and remove metal ions and chlorides is a key issue that needs to be urgently addressed in the field of high-purity chlorine production. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a production device and a production method of electronic grade chlorine to solve the deficiencies in the prior art.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A production device for electronic grade chlorine comprises a raw material storage tank, a gasification device, a dehydration tower, a light component removal tower, a heavy component removal tower, a compressor and a product collection bottle which are connected in sequence.

[0008] Furthermore, the above-mentioned electronic-grade chlorine production device also includes a light component removal tower condenser and a light component removal tower reboiler; the light component removal tower condenser is arranged at the top of the light component removal tower and is connected to the light component removal tower; the light component removal tower reboiler is arranged at the bottom of the light component removal tower and is cyclically connected to the light component removal tower.

[0009] A further beneficial effect of the above method is that the non-condensable gas in the light component removal tower is extracted from the light component removal tower condenser; part of the tower bottom flow enters the light component removal tower again through the reboiler to exchange heat and mass with the tower top reflux material.

[0010] Furthermore, the production device of the electronic grade chlorine also includes a de-heavy component tower full condenser and a de-heavy component tower reboiler; the de-heavy component tower full condenser is arranged at the top of the de-heavy component tower and is connected to the de-heavy component tower; the de-heavy component tower reboiler is arranged at the bottom of the de-heavy component tower and is cyclically connected to the de-heavy component tower.

[0011] The above further beneficial effect is that the full condenser of the heavy component removal tower provides liquid phase reflux in the tower, thereby achieving efficient separation effect. The reboiler of the heavy component removal tower provides the ascending gas phase in the tower, providing the necessary energy for the distillation operation, and also promoting the heat and mass transfer between the vapor and liquid phases in the tower.

[0012] An electronic grade chlorine production device adopts the above electronic grade chlorine production device, specifically comprising the following steps:

[0013] (1) Pumping industrial liquid chlorine in the raw material storage tank into a gasification device for gasification, removing metal, non-metal chlorides and particulate matter, and obtaining chlorine gas;

[0014] (2) passing the chlorine gas from the bottom of the tower into a dehydration tower filled with an adsorbent, removing water and then extracting it from the top of the tower to obtain dehydrated chlorine gas;

[0015] (3) passing the dehydrated chlorine into a light component removal tower, the light component impurities are discharged from the top of the tower, and the light chlorine is obtained in the bottom of the tower;

[0016] (4) The light chlorine gas is passed into a heavy component removal tower, and the heavy component impurities are discharged from the bottom of the tower. The electronic grade chlorine product is collected from the top of the tower, compressed by a compressor and stored in a product collection bottle.

[0017] Furthermore, in the above step (1), the industrial liquid chlorine contains light impurities such as water, oxygen, nitrogen, carbon dioxide, carbon monoxide, methane and hydrogen, and heavy impurities such as nitrogen trichloride and phosphorus trichloride; the gasification device is heated by hot water; the temperature of the hot water is 30-40°C; and the working pressure of the gasification is lower than 0.55MPa.

[0018] A further beneficial effect of the above method is that steam heating is used to avoid explosion and ensure safe operation.

[0019] Furthermore, in the above step (2), the feed temperature of the dehydration tower is 25-35° C., and the feed pressure is 0.1 MPa; the adsorbent is at least one of activated carbon, alumina, 3A molecular sieve, 4A molecular sieve, 5A molecular sieve and 13X molecular sieve, and all are dried with high-temperature chlorine.

[0020] The above method has the further beneficial effect that, by drying the adsorbent, its water adsorption capacity is enhanced, so that the volume fraction of water in chlorine is less than 2×10 -4 %.

[0021] Furthermore, in the above step (3), the absolute pressure of the light component removal tower is 0.03 to 0.18 MPa, the tower top temperature is -40 to -35°C, and the tower bottom temperature is -30 to -20°C; the light component impurities are oxygen, nitrogen, carbon dioxide, carbon monoxide, methane and hydrogen.

[0022] A further beneficial effect of the above method is that, through the light component removal treatment, the content of light component impurities in chlorine gas is lower than the standard value.

[0023] Furthermore, in the above step (4), the absolute pressure of the heavy component removal tower is 0.05 to 0.22 MPa, the tower top temperature is -30 to -15°C, and the tower bottom temperature is -5 to 10°C; the heavy component impurities are nitrogen trichloride and phosphorus trichloride.

[0024] A further beneficial effect of the above method is that, through the de-heavy treatment, the content of heavy impurities in chlorine gas is lower than the standard value.

[0025] Furthermore, in the above steps (2) to (4), the dehydration tower, the light component removal tower and the heavy component removal tower are all packed towers or plate towers.

[0026] Furthermore, in the above steps (1)-(4), the fluid delivery pipelines between the raw material storage tank, the gasification device, the dehydration tower, the light component removal tower, the heavy component removal tower, the compressor and the product collection bottle are made of 16Mn carbon steel, polytetrafluoroethylene, copper-plastic composite pipe or titanium pipe, and the delivery pump is a corrosion-resistant pump.

[0027] It can be seen from the above technical solution that compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] The invention adopts a gasification device, a dehydration tower, a light component removal tower and a heavy component removal tower for separation and purification. On the basis of removing impurities such as water, oxygen, nitrogen and the like, metal ions and chlorides such as nitrogen trichloride in chlorine are further removed, so as to avoid explosion caused by long-term mixing of nitrogen trichloride and chlorine. Meanwhile, the purity of the product is greatly improved. The invention has the characteristics of simple process, low production cost and high product purity, is easy to realize industrialized production, can effectively reduce the production cost of the enterprise, and greatly improve the economic benefits of the enterprise.

[0029] The electronic-grade chlorine product prepared by the invention has high purity, can meet the high requirements of the electronics industry, and can be applied to the fields of semiconductors, integrated circuits, optical fiber communications, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] 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 only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0031] Figure 1 It is a structural schematic diagram of an electronic grade chlorine production device and a process flow chart of its production method.

[0032] Among them, 1-raw material storage tank, 2-gasification device, 3-dehydration tower, 4-light component removal tower, 5-light component removal tower condenser, 6-light component removal tower reboiler, 7-heavy component removal tower, 8-heavy component removal tower full condenser, 9-heavy component removal tower reboiler, 10-compressor, 11-product collection bottle. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0034] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0038] Example 1

[0039] Electronic grade chlorine production plant, such as Figure 1 As shown, it includes a raw material storage tank 1, a gasification device 2, a dehydration tower 3, a light component removal tower 4, a heavy component removal tower 7, a compressor 10 and a product collection bottle 11 which are connected in sequence.

[0040] Example 2

[0041] Electronic grade chlorine production plant, such as Figure 1 As shown, it includes a raw material storage tank 1, a gasification device 2, a dehydration tower 3, a light component removal tower 4, a heavy component removal tower 7, a compressor 10 and a product collection bottle 11 which are connected in sequence;

[0042] It also includes a light component removal tower condenser 5 and a light component removal tower reboiler 6; the light component removal tower condenser 5 is arranged at the top of the light component removal tower 4 and is connected to the light component removal tower 4; the light component removal tower reboiler 6 is arranged at the bottom of the light component removal tower 4 and is cyclically connected to the light component removal tower 4;

[0043] It also includes a deheaving component tower full condenser 8 and a deheaving component tower reboiler 9; the deheaving component tower full condenser 8 is arranged at the top of the deheaving component tower 7 and is connected to the deheaving component tower 7; the deheaving component tower reboiler 9 is arranged at the bottom of the deheaving component tower 7 and is cyclically connected to the deheaving component tower 7.

[0044] Example 3

[0045] The production method of electronic grade chlorine adopts the production device of electronic grade chlorine in Example 1, such as Figure 1 As shown, the specific steps include:

[0046] (1) The industrial liquid chlorine in the raw material storage tank 1 is pumped into the gasification device 2 for gasification. The gasification device 2 is heated by hot water at a temperature of 30° C. and has a working pressure of 0.5 MPa to remove metal, non-metal chlorides and particulate matter to obtain chlorine gas;

[0047] (2) passing chlorine from the bottom of the tower into a dehydration tower 3 filled with a 13X molecular sieve dried at high temperature for chlorine, wherein the dehydration tower 3 is a packed tower, the feed temperature is 30° C., the feed pressure is 0.1 MPa, and the dehydrated chlorine is obtained from the top of the tower after water is removed;

[0048] (3) passing the dehydrated chlorine into a light component removal tower 4, which is a packed tower with an absolute pressure of 0.1 MPa, a tower top temperature of -35°C, a tower bottom temperature of -25°C, oxygen, nitrogen, carbon dioxide, carbon monoxide, methane and hydrogen are discharged from the tower top, and light chlorine is obtained in the tower bottom;

[0049] (4) The light chlorine gas is passed into the heavy component removal tower 7, which is a packed tower with an absolute pressure of 0.1 MPa, a tower top temperature of -20°C, and a tower bottom temperature of 5°C. Nitrogen trichloride and phosphorus trichloride are discharged from the tower bottom, and an electronic grade chlorine product is produced from the tower top, compressed by a compressor 10, and stored in a product collection bottle 11.

[0050] Example 4

[0051] The production method of electronic grade chlorine adopts the production device of electronic grade chlorine in Example 1, such as Figure 1 As shown, the specific steps include:

[0052] (1) The industrial liquid chlorine in the raw material storage tank 1 is pumped into the gasification device 2 for gasification. The gasification device 2 is heated by hot water at a temperature of 25° C. and has a working pressure of 0.4 MPa to remove metal, non-metal chlorides and particulate matter to obtain chlorine gas;

[0053] (2) passing chlorine from the bottom of the tower into a dehydration tower 3 filled with activated carbon dried by high-temperature chlorine, the dehydration tower 3 being a packed tower, the feed temperature being 25° C., the feed pressure being 0.1 MPa, and the dehydrated chlorine is obtained from the top of the tower after water is removed;

[0054] (3) passing the dehydrated chlorine into a light component removal tower 4, which is a packed tower with an absolute pressure of 0.05 MPa, a tower top temperature of -35°C, a tower bottom temperature of -25°C, oxygen, nitrogen, carbon dioxide, carbon monoxide, methane and hydrogen are discharged from the tower top, and light chlorine is obtained in the tower bottom;

[0055] (4) The light chlorine gas is passed into the heavy component removal tower 7, which is a packed tower with an absolute pressure of 0.05 MPa, a tower top temperature of -20°C, and a tower bottom temperature of 5°C. Nitrogen trichloride and phosphorus trichloride are discharged from the tower bottom, and an electronic grade chlorine product is produced from the tower top, compressed by a compressor 10, and stored in a product collection bottle 11.

[0056] Example 5

[0057] The production method of electronic grade chlorine adopts the production device of electronic grade chlorine in Example 1, such as Figure 1 As shown, the specific steps include:

[0058] (1) The industrial liquid chlorine in the raw material storage tank 1 is pumped into the gasification device 2 for gasification. The gasification device 2 is heated by hot water at a temperature of 35° C. and has a working pressure of 0.45 MPa to remove metal, non-metal chlorides and particulate matter to obtain chlorine gas;

[0059] (2) passing chlorine from the bottom of the tower into a dehydration tower 3 filled with activated carbon dried by high-temperature chlorine, the dehydration tower 3 being a packed tower, the feed temperature being 35° C., the feed pressure being 0.1 MPa, and the dehydrated chlorine is obtained from the top of the tower after water is removed;

[0060] (3) passing the dehydrated chlorine into a light component removal tower 4, which is a packed tower with an absolute pressure of 0.15 MPa, a tower top temperature of -35°C, a tower bottom temperature of -25°C, oxygen, nitrogen, carbon dioxide, carbon monoxide, methane and hydrogen are discharged from the tower top, and light chlorine is obtained in the tower bottom;

[0061] (4) The light chlorine gas is passed into the heavy component removal tower 7, which is a packed tower with an absolute pressure of 0.15 MPa, a tower top temperature of -20°C, and a tower bottom temperature of 5°C. Nitrogen trichloride and phosphorus trichloride are discharged from the tower bottom, and an electronic grade chlorine product is produced from the tower top, compressed by a compressor 10, and stored in a product collection bottle 11.

[0062] Comparative Example

[0063] Example 1 of the Chinese invention patent with application number 201310345584.1 discloses a method for preparing electronic grade high-purity chlorine using industrial liquid chlorine as a raw material, which specifically comprises the following steps:

[0064] a. The raw material industrial chlorine is gasified to remove most of the metal ions at a pressure of 0.4MP and a temperature of 20℃ at 1m 3 / h flow enters from the bottom of the primary drying tower 1 filled with 13X zeolite molecular sieve No. DH05, and comes out from the top of the tower after most of the water is removed by adsorption;

[0065] b. Then enter the bottom of the secondary drying tower equipped with 13X zeolite molecular sieve No. DH06, and after deep dehydration, remove trace moisture and come out from the top of the tower. After removal, the moisture content in the chlorine gas is less than 0.5ppm;

[0066] c. Then it enters from the bottom of the adsorption tower equipped with SSZ-13 zeolite molecular sieve, adsorbs and removes carbon dioxide and trace amounts of water, and then comes out from the top of the tower. The carbon dioxide content after adsorption is less than 2ppm;

[0067] d. Decompress to 0.1MP, condense to -20℃ and then enter the distillation tower. Nitrogen, oxygen, hydrogen, carbon monoxide, methane and other low-boiling point gases are discharged from the top of the tower. After the tail gas is formed, it is absorbed and recovered in the sodium removal section. After removal, the nitrogen content is less than 2ppm, the oxygen content is less than 1ppm, the carbon monoxide content is less than 1ppm, and the methane content is less than 1ppm;

[0068] e. The purity of the high-purity liquid chlorine coming out from the bottom of the distillation tower reaches more than 99.999%. It is bottled by the compression filling system. The total metal ion content of the bottled high-purity liquid chlorine is less than 0.3ppm.

[0069] Performance Testing

[0070] The electronic grade chlorine products prepared in Examples 3-5 were respectively tested for the contents (mass fractions) of chlorine, metal ions, non-metallic chlorides, moisture and other gaseous impurities (oxygen, nitrogen, carbon dioxide, etc.), and compared with the comparative examples.

[0071] The results are shown in Table 1.

[0072] Table 1 Content of each component of electronic grade chlorine product in Example 3-5

[0073]

[0074] As can be seen from Table 1, the purity of the electronic-grade chlorine products of Examples 3-5 of the present invention is all above 99.999%, which is better than the prior art, and does not contain metal ions and non-metal chlorides.

[0075] The above experiments show that the electronic-grade chlorine product prepared by the present invention has high purity, can meet the high requirements of the electronics industry, and can be applied to the fields of semiconductors, integrated circuits, and optical fiber communications.

[0076] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0077] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A production device for electronic grade chlorine, characterized in that: The utility model comprises a raw material storage tank, a gasification device, a dehydration tower, a light component removal tower, a heavy component removal tower, a compressor and a product collection bottle which are connected in sequence.

2. The production device of electronic grade chlorine according to claim 1, characterized in that: It also includes a light component removal tower condenser and a light component removal tower reboiler; the light component removal tower condenser is arranged at the top of the light component removal tower and is connected to the light component removal tower; the light component removal tower reboiler is arranged at the bottom of the light component removal tower and is cyclically connected to the light component removal tower.

3. The production device of electronic grade chlorine according to claim 1, characterized in that: It also includes a de-heavy component tower full condenser and a de-heavy component tower reboiler; the de-heavy component tower full condenser is arranged at the top of the de-heavy component tower and is connected to the de-heavy component tower; the de-heavy component tower reboiler is arranged at the bottom of the de-heavy component tower and is cyclically connected to the de-heavy component tower.

4. An electronic grade chlorine production equipment, characterized in that: The production device of electronic grade chlorine as claimed in claim 1 specifically comprises the following steps: (1) Pumping industrial liquid chlorine in the raw material storage tank into a gasification device for gasification, removing metal, non-metal chlorides and particulate matter, and obtaining chlorine gas; (2) passing the chlorine gas from the bottom of the tower into a dehydration tower filled with an adsorbent, removing water and then extracting it from the top of the tower to obtain dehydrated chlorine gas; (3) passing the dehydrated chlorine into a light component removal tower, the light component impurities are discharged from the top of the tower, and the light chlorine is obtained in the bottom of the tower; (4) The light chlorine gas is passed into a heavy component removal tower, and the heavy component impurities are discharged from the bottom of the tower. The electronic grade chlorine product is collected from the top of the tower, compressed by a compressor and stored in a product collection bottle.

5. The production equipment of electronic grade chlorine according to claim 4, characterized in that: In step (1), the gasification device is heated by hot water; the temperature of the hot water is 30-40° C.; and the working pressure of the gasification is lower than 0.55 MPa.

6. The production equipment of electronic grade chlorine according to claim 4, characterized in that: In step (2), the feed temperature of the dehydration tower is 25-35° C., and the feed pressure is 0.1 MPa; the adsorbent is at least one of activated carbon, alumina, 3A molecular sieve, 4A molecular sieve, 5A molecular sieve and 13X molecular sieve, and all are dried with high-temperature chlorine.

7. The production equipment of electronic grade chlorine according to claim 4, characterized in that: In step (3), the absolute pressure of the light component removal tower is 0.03 to 0.18 MPa, the tower top temperature is -40 to -35°C, and the tower bottom temperature is -30 to -20°C; the light component impurities are oxygen, nitrogen, carbon dioxide, carbon monoxide, methane and hydrogen.

8. The production equipment of electronic grade chlorine according to claim 4, characterized in that: In step (4), the absolute pressure of the heavy component removal tower is 0.05 to 0.22 MPa, the tower top temperature is -30 to -15°C, and the tower bottom temperature is -5 to 10°C; the heavy component impurities are nitrogen trichloride and phosphorus trichloride.

9. The production equipment of electronic grade chlorine according to claim 4, characterized in that: In steps (2) to (4), the dehydration tower, light component removal tower and heavy component removal tower are all packed towers or plate towers.

10. The production equipment of electronic grade chlorine according to claim 4, characterized in that: In steps (1)-(4), the fluid conveying pipelines between the raw material storage tank, gasification device, dehydration tower, light component removal tower, heavy component removal tower, compressor and product collection bottle are made of 16Mn carbon steel, polytetrafluoroethylene, copper-plastic composite pipe or titanium pipe.

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