Carbonyl sulfide synthesis device
By using the design of melting sulfur tank and sulfur pressing tank separation, nitrogen purge and three-stage cooling section in the carbonyl sulfur synthesis device, the problem of sulfur vapor blockage is solved, the impurity content of synthesis gas is reduced, the purity of carbonyl sulfur is improved, and the subsequent purification steps are simplified.
Patent Information
- Application Number
- CN202421835747.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-31
- Publication Date
- 2025-07-04
- Estimated Expiration
- 2034-07-31
AI Technical Summary
In the prior art, sulfur vapor tends to solidify and block heat exchangers, pipelines or containers during the synthesis of carbonyl sulfur, and at the same time, the impurity content of synthesis gas is high, resulting in difficulty in subsequent distillation and purification.
The sulfur melting tank and the sulfur pressing tank are separated, and high-purity nitrogen is used to purge to reduce impurities. The third-level cooling section is gradually cooled to avoid the rapid cooling and solidification of sulfur vapor. The synthesis furnace uses high-purity carbon monoxide as raw material, and the third-level cooling section uses carbon monoxide, thermal oil and circulating water as the cooling source respectively.
It effectively reduces the risk of sulfur vapor solidification and blockage, reduces the impurity content in the synthesis gas, improves the purity of carbonyl sulfur, and simplifies the subsequent purification process.
Smart Images
Figure CN223055582U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of gas preparation, and particularly relates to a carbonyl sulfide synthesis device. Background Art
[0002] Carbonyl sulfide (COS) is widely used in the pharmaceutical and other chemical industries. High-purity carbonyl sulfide is widely used as an electronic special gas in the dry etching process in the field of integrated circuit semiconductor technology, and can also be used as a sidewall protection gas for the preparation of precursors and dry etching processes in the chemical vapor deposition of the semiconductor industry.
[0003] Generally, high-purity carbonyl sulfide requires a carbonyl sulfide content of more than 99.999%, and has extremely high requirements for impurities such as moisture. One of the common methods for synthesizing carbonyl sulfide is to react carbon monoxide and sulfur under the action of catalysts such as ferrous sulfide in a high-temperature environment. In the conventional synthesis method, there are very many impurities in the synthesized gas. This is because the raw materials sulfur and carbon monoxide contain impurities such as moisture and oxygen, and many side reactions will occur during the synthesis process. For example, carbon monoxide reacts with oxygen or moisture to generate carbon dioxide impurities. Carbonyl sulfide is extremely easy to react with moisture to generate carbon dioxide and hydrogen sulfide impurities. Carbon monoxide and sulfur reaction can also generate carbon dioxide and carbon disulfide impurities. Too many impurities bring great difficulties to the subsequent rectification and purification.
[0004] In addition, during the synthesis process of carbonyl sulfide, sulfur needs to be heated and vaporized into a gaseous state before participating in the reaction. During the stage of using circulating water for cooling, some unreacted gaseous sulfur solidifies into solid sulfur due to a sharp temperature drop. The solid sulfur adheres to the heat exchanger, pipeline or container, and will cause blockage of the heat exchanger, pipeline and container after a period of time, bringing great inconvenience to production. Summary of the Utility Model
[0005] The purpose of the utility model is to provide a carbonyl sulfide synthesis device, which helps to solve the problem of sulfur vapor solidification blocking the heat exchanger, pipeline or container, and at the same time can synthesize carbonyl sulfide with relatively few impurities.
[0006] The technical solution of the utility model lies in: a carbonyl sulfide synthesis device, including a molten sulfur tank, the bottom of the molten sulfur tank is connected to a sulfur charging tank through a pipeline, a nitrogen purging structure is arranged on the sulfur charging tank, the bottom of the sulfur charging tank is connected to the bottom of a synthesis furnace with a reaction section and a three-stage cooling section through a pipeline, a high-purity carbon monoxide injection pipe is also installed at the bottom of the synthesis furnace, and a synthesis gas output pipe is arranged at the top of the synthesis furnace.
[0007] Further, electric heating structures are arranged on the outer walls of the molten sulfur tank and the sulfur charging tank, and at the bottom of the synthesis furnace and the outer wall of the reaction section.
[0008] Further, the pipeline at the bottom of the sulfur melting tank is connected to the sulfur charging tank through a sulfur pump, and a feeding valve is arranged on the pipeline at the bottom of the sulfur charging tank.
[0009] Further, the nitrogen purging structure includes a nitrogen input pipe leading to the bottom of the sulfur charging tank, and an exhaust pipe is arranged at the top of the sulfur charging tank and is equipped with a vent valve.
[0010] Further, the three-stage cooling section is composed of a first cooling section, a second cooling section, and a third cooling section which are sequentially arranged from bottom to top on the upper side of the reaction section.
[0011] Further, the first cooling section is a shell-and-tube heat exchanger. A high-purity carbon monoxide input pipe is installed at the shell-side inlet of the shell-and-tube heat exchanger, and the shell-side outlet of the shell-and-tube heat exchanger is connected to a high-purity carbon monoxide injection pipe.
[0012] Further, the second cooling section includes a first coil arranged in the synthesis furnace. The output end of the first coil is connected to a heat exchanger using heat-conducting oil as a cold source through a pipeline, and a heat-conducting oil pump is arranged on the pipeline between the output end of the heat exchanger and the input end of the first coil.
[0013] Further, the third cooling section includes a second coil arranged in the synthesis furnace, and the cold source of the second coil is circulating water.
[0014] Compared with the prior art, the present utility model has the following advantages:
[0015] 1. The sulfur melting tank and the sulfur pressing tank are separated. High-purity nitrogen is used to purge first and then press sulfur to reduce the impurity content in the sulfur entering the reaction. At the same time, high-purity carbon monoxide is used as a raw material to reduce the content of impurities and components that may generate other impurities from the source.
[0016] 2. The synthesis gas of the synthesis furnace adopts a three-stage cooling type. The first stage uses raw material carbon monoxide as a cold source to cool the synthesis gas and preheat the raw material carbon monoxide at the same time. The second stage uses relatively high-temperature heat-conducting oil as a cold source, and the third stage uses circulating water as a cold source. The three-stage gradually decreasing temperature cooling mode enables the sulfur vapor to participate in liquefying and flowing back to the reactor to continue the reaction, avoiding the rapid cooling and solidification of the sulfur vapor, which may block the heat exchanger, pipeline or container. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is a structural schematic diagram of the present utility model;
[0018] Figure 2 is a connection structure diagram of the sulfur melting tank and the sulfur charging tank of the present utility model;
[0019] In the figure: 10 - sulfur melting tank; 11 - sulfur pump; 20 - sulfur charging tank; 21 - feed valve; 22 - nitrogen input pipe; 23 - vent valve; 30 - synthesis furnace; 31 - reaction section; 32 - three - stage cooling section; 33 - high - purity carbon monoxide injection pipe; 34 - syngas output pipe; 35 - shell - and - tube heat exchanger; 351 - high - purity carbon monoxide input pipe; 36 - first coil; 361 - heat exchanger; 362 - heat - conducting oil pump; 37 - second coil. Specific embodiments
[0020] To make the above - mentioned features and advantages of the present utility model more understandable, specific embodiments are given below in conjunction with the accompanying drawings and described in detail as follows. However, the present utility model is not limited thereto.
[0021] Reference Figure 1 and Figure 2
[0022] A carbonyl sulfide synthesis device includes a sulfur melting tank 10. The pipeline at the bottom of the sulfur melting tank is connected to a sulfur charging tank 20 through a sulfur pump 11 to pressurize and transport liquid sulfur to the sulfur charging tank. A nitrogen purging structure is provided on the sulfur charging tank. The bottom of the sulfur charging tank is connected to the bottom of a synthesis furnace 30 having a reaction section 31 and a three - stage cooling section 32 through a pipeline, and a feed valve 21 is provided on the pipeline at the bottom of the sulfur charging tank. A high - purity carbon monoxide injection pipe 33 is also installed at the bottom of the synthesis furnace, and a syngas output pipe 34 is provided at the top of the synthesis furnace.
[0023] In this embodiment, electric heating structures are provided on the outer walls of the sulfur melting tank to melt sulfur into a liquid state; electric heating structures are provided on the outer walls of the sulfur charging tank to prevent sulfur from cooling and solidifying; the bottom of the synthesis furnace and the outer walls of the reaction section are heated by wrapping electric heaters on the outer walls, which helps to evaporate sulfur into gaseous sulfur vapor.
[0024] In this embodiment, the nitrogen purging structure includes a nitrogen input pipe 22 leading to the bottom of the sulfur charging tank. An exhaust pipe is provided at the top of the sulfur charging tank and a vent valve 23 is installed to introduce high - purity nitrogen (nitrogen content 99.999%) into the sulfur charging tank, and impurities such as moisture and oxygen in the sulfur are carried out and vented under nitrogen purging.
[0025] In this embodiment, the three - stage cooling section is composed of a first cooling section, a second cooling section, and a third cooling section which are arranged in sequence from bottom to top on the upper side of the reaction section.
[0026] In this embodiment, the first cooling section is a shell-and-tube heat exchanger 35. The shell-and-tube heat exchanger uses raw material carbon monoxide as the cold source. A high-purity carbon monoxide input pipe 351 is installed at the inlet of the shell side of the shell-and-tube heat exchanger, which preheats the raw material carbon monoxide while cooling the synthesis gas. The outlet of the shell side of the shell-and-tube heat exchanger is connected to a high-purity carbon monoxide injection pipe. The synthesis gas flows through the tube side, and partially liquefied sulfur flows down through the tubes to the reaction section to continue the reaction.
[0027] In this embodiment, the second cooling section includes a first coil 36 disposed in the synthesis furnace. The output end of the first coil is connected to a heat exchanger 361 using high-temperature heat transfer oil as the cold source through a pipeline. A heat transfer oil pump 362 is provided on the pipeline between the output end of the heat exchanger and the input end of the first coil. After the heat transfer oil is heated, it is cooled by hot water, and then pressurized and transported to the first coil by the heat transfer oil pump. Partially liquefied sulfur also flows down through the tubes to the reaction section to continue the reaction.
[0028] In this embodiment, the third cooling section includes a second coil 37 disposed in the synthesis furnace. The cold source of the second coil is circulating water.
[0029] During use, raw material sulfur (solid, in packages or in blocks) is added to the sulfur melting tank 10, and then the sulfur melting tank 10 is heated to about 120°C to 150°C to melt the sulfur into a liquid state. Then it is pressurized and transported to the sulfur pressure feeding tank 20 by a sulfur pump 11. The outer wall of the sulfur pressure feeding tank 20 is also electrically heated. First, the feed valve 21 is closed, the vent valve 23 is opened, and high-purity nitrogen (nitrogen content 99.999%) is introduced into the sulfur pressure feeding tank 20. Under the nitrogen purge, impurities such as moisture and oxygen in the sulfur are carried out and vented. Then the vent valve 23 is closed, the feed valve 21 is opened, and high-purity nitrogen is continuously introduced. The pressure in the sulfur pressure feeding tank 20 rises to about 0.9 to 1.1 MPa, and under the action of the pressure, the liquid sulfur is transported to the synthesis furnace 30.
[0030] High-purity carbon monoxide (carbon monoxide content 99.999%) is heated to 250°C to 350°C by high-temperature (about 400°C to 500°C) synthesis gas in the synthesis furnace 30 and then introduced into the liquid sulfur at the bottom of the synthesis furnace. The heating temperature of the synthesis furnace is controlled at 450°C to 550°C. At this time, part of the sulfur evaporates into gaseous sulfur vapor. The sulfur vapor and carbon monoxide rise upward to the reaction section 31. The reaction section 31 is filled with common catalysts such as ferrous sulfide and molecular sieve. In the reaction section 31, the sulfur vapor and carbon monoxide react to generate carbonyl sulfide, side reactions generate carbon dioxide and carbon disulfide, and trace moisture participates in the reaction to generate hydrogen sulfide impurities.
[0031] Control the carbon monoxide to be slightly in excess according to the syngas composition. The syngas composed of unreacted carbon monoxide, carbonyl sulfide, sulfur vapor, etc. continues to rise and enters the three-stage cooling section 32. In the first cooling section, a raw material carbon monoxide serves as a cold source to cool the syngas while preheating the raw material carbon monoxide. The carbon monoxide flows through the shell side, and the syngas flows through the tube side. The partially liquefied sulfur flows down through the tubes to the reaction section 31 to continue the reaction; in the second cooling section, the partially liquefied sulfur also flows down through the tubes to the reaction section 31 to continue the reaction; the cooled syngas is further cooled by the third cooling section. The three-stage gradually decreasing temperature cooling mode gradually cools the syngas to 40-50 °C, enabling the sulfur vapor to participate in liquefaction and reflux to the reaction section 31 to continue the reaction, and avoiding the rapid cooling and solidification of the sulfur vapor to block the heat exchanger, pipeline or container. Then the syngas goes to the subsequent purification device.
[0032] If terms such as "first" and "second" are used in the above text to limit components, those skilled in the art should be aware that: the use of "first" and "second" is only for the convenience of differentiating components in description. Unless otherwise stated, these terms have no special meaning.
[0033] If the present utility model discloses or involves components or structural members that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connected by bolts or screws), or it can also be understood as: a non-detachable fixed connection (for example, riveting, welding). Of course, the mutual fixed connection can also be replaced by an integral structure (for example, manufactured integrally by casting process) (except when it is obviously impossible to adopt the integral forming process).
[0034] In addition, unless otherwise stated, the terms used to represent the positional relationship or shape in any technical solution disclosed in the present utility model include states or shapes that are approximate, similar or close to it.
[0035] Any component provided by the present utility model can either be assembled from a plurality of separate components or be a single component manufactured by an integral forming process.
[0036] The above is only the preferred embodiment of the present utility model. All equivalent changes and modifications made according to the scope of the patent application of the present utility model shall fall within the scope covered by the present utility model.
Claims
1. A carbonyl sulfide synthesis device, including a molten sulfur tank, characterized in that, The bottom of the sulfur melting tank is connected to the sulfur charging tank through a pipeline. A nitrogen purging structure is provided on the sulfur charging tank. The bottom of the sulfur charging tank is connected to the bottom of a synthesis furnace having a reaction section and a three-stage cooling section through a pipeline. A high-purity carbon monoxide injection pipe is also installed at the bottom of the synthesis furnace, and a syngas output pipe is provided at the top of the synthesis furnace.
2. The carbonyl sulfide synthesis device according to claim 1, characterized in that, Electric heating structures are provided on the outer walls of the sulfur melting tank and the sulfur charging tank, as well as at the bottom of the synthesis furnace and the outer wall of the reaction section.
3. The carbonyl sulfide synthesis device according to claim 1 or 2, characterized in that, The pipeline at the bottom of the sulfur melting tank is connected to the sulfur charging tank through a sulfur pump, and a feed valve is provided on the pipeline at the bottom of the sulfur charging tank.
4. The carbonyl sulfide synthesis device according to claim 1, characterized in that, The nitrogen purging structure includes a nitrogen input pipe leading to the bottom of the sulfur charging tank. An exhaust pipe is provided at the top of the sulfur charging tank and a vent valve is installed.
5. A carbonyl sulfide synthesis device according to claim 1, 2 or 4, characterized in that, The three-stage cooling section is composed of a first cooling section, a second cooling section, and a third cooling section that are sequentially arranged from bottom to top on the upper side of the reaction section.
6. The carbonyl sulfide synthesis device according to claim 5, wherein, The first cooling section is a shell-and-tube heat exchanger. A high-purity carbon monoxide input pipe is installed at the shell-side inlet of the shell-and-tube heat exchanger, and the shell-side outlet of the shell-and-tube heat exchanger is connected to the high-purity carbon monoxide injection pipe.
7. The carbonyl sulfide synthesis device according to claim 5, characterized in that, The second cooling section includes a first coil arranged in the synthesis furnace. The output end of the first coil is connected to a heat exchanger using heat-conducting oil as a cold source through a pipeline, and a heat-conducting oil pump is provided on the pipeline between the output end of the heat exchanger and the input end of the first coil.
8. The carbonyl sulfide synthesis device according to claim 5, wherein The third cooling section includes a second coil arranged in the synthesis furnace, and the cold source of the second coil is circulating water.