A system for automatic sampling and analysis of heptafluoroisopropyl bromide production control

Abstract

The utility model belongs to heptafluoroisopropyl bromide preparation technical field, concretely relates to a kind of heptafluoroisopropyl bromide automatic sampling analysis production control system;Including reaction unit, post-processing unit, sampling analysis unit and DCS control unit;The reaction unit includes premixing jar and reactor, the post-processing unit includes water scrubbing tower, alkali washing tower, gas holder, compressor, crude product storage tank and rectifying column connected by pipeline in proper order, the sampling analysis unit includes gas chromatograph host computer;The crude product and product of heptafluoroisopropyl bromide are rapidly, accurately detected by gas chromatograph host computer, and process parameters are adjusted in time according to sampling analysis result by DCS control unit, improve the consistency of product quality and the stability of production system.

Description

Technical Field

[0001] This utility model belongs to the field of heptafluoroisopropyl bromide preparation technology, specifically relating to an automatic sampling and analysis production control system for heptafluoroisopropyl bromide. Background Technology

[0002] The traditional production process for preparing heptafluoroisopropyl bromide using bromine and organofluorine compounds typically employs offline laboratory analysis methods. Due to the high requirements for product index analysis, this method suffers from complex sampling and analysis, long processing times, and high labor costs. Consequently, the analysis results are delayed, and the adjustment of process parameters is also delayed, affecting the consistency of product quality and the stability of the production system. This method cannot meet the requirements for refined operation of the production process. Summary of the Invention

[0003] The purpose of this invention is to provide an automatic sampling and analysis production control system for heptafluoroisopropyl bromide. This invention uses a gas chromatography mainframe to quickly and accurately detect crude heptafluoroisopropyl bromide and finished products, and adjusts process parameters in a timely manner through a DCS control unit based on the sampling and analysis results, thereby improving the consistency of product quality and the stability of the production system.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: An automated sampling and analysis production control system for heptafluoroisopropyl bromide is characterized by comprising a reaction unit, a post-processing unit, a sampling and analysis unit, and a DCS control unit. The reaction unit includes a premixing vessel and a reactor. The premixing vessel is equipped with a bromine inlet pipe and an organic fluoride inlet pipe at the top. The premixing vessel is also equipped with a mixed gas outlet pipe connected to the reactor. The reactor is equipped with an online thermometer and an electric heating device. The online thermometer and the electric heating device are electrically connected to the DCS control unit. The post-processing unit includes a water washing tower, an alkaline washing tower, a gas storage tank, a compressor, a crude product storage tank, and a distillation tower connected in sequence. The reactor is connected to the water washing tower, the alkaline washing tower, the gas storage tank, and the compressor in sequence via a heptafluoroisopropyl bromide crude product gas pipeline. The compressor is then connected to the crude product storage tank and the distillation tower in sequence via a heptafluoroisopropyl bromide crude product liquid pipeline. A crude product pump is installed on the pipeline between the crude product storage tank and the distillation tower. A transfer valve is installed on the heptafluoroisopropyl bromide liquid outlet pipeline of the distillation tower. An online level gauge is installed in the crude product storage tank. An online level gauge and an online thermometer are installed on the distillation tower. The online level gauge, the online thermometer, the crude product pump, and the transfer valve are electrically connected to the DCS control unit. The sampling and analysis unit includes a gas chromatograph host, which is electrically connected to the DCS control unit. A crude product sampling tube is located at the bottom of the crude product storage tank, and a product sampling tube is located on the heptafluoroisopropyl bromide outlet line of the distillation column. The crude product sampling tube and the product sampling tube are combined into a sampling manifold, which is then connected to the gas chromatograph host. The gas chromatograph host is also equipped with a reflux pipe connected to a gas storage tank. Both the crude product sampling tube and the product sampling tube are equipped with an electrovaporator and a dehumidifier, used to sequentially vaporize, dehumidify, and remove impurities from the sample flowing out of the crude product storage tank or distillation column before it enters the gas chromatograph host through the sampling manifold.

[0005] Preferably, the crude product sampling tube is equipped with a first solenoid valve, and the product sampling tube is equipped with a second solenoid valve; the solenoid valves are electrically connected to the DCS control unit.

[0006] Preferably, the sampling manifold is equipped with an online pressure gauge and a pressure regulating valve, which are electrically connected to the DCS control unit; the DCS control unit adjusts the opening of the pressure regulating valve according to the inlet pressure setting value of the chromatography host.

[0007] Preferably, both the crude product sampling tube and the product sampling tube are provided with return branch pipes connected to the gas storage tank on the pipeline before the electrovaporizer.

[0008] Compared with the prior art, the present invention has the following beneficial effects: To address the problems of complex, time-consuming, and labor-intensive sampling and analysis in existing technologies, this invention provides an automated sampling and analysis production control system for heptafluoroisopropyl bromide. This system utilizes a gas chromatograph host to achieve rapid, accurate, and stable index analysis, and uses a DCS control unit to provide real-time feedback and optimization of process parameters. This eliminates sampling and analysis delays, reduces the operational risks and costs of manual sampling and analysis, and improves product quality consistency and production system stability. Attached Figure Description

[0009] Figure 1 This is a process flow diagram of the automatic sampling and analysis production control system for heptafluoroisopropyl bromide of this utility model.

[0010] In the diagram: bromine inlet pipe 101, organofluorine inlet pipe 102, premixing vessel 103, reactor 104, electric heating device 105, online thermometer 106, water washing tower 201, alkali washing tower 202, gas storage tank 203, compressor 204, crude product storage tank 205, distillation column 206, crude product pump 207, transfer valve 208, gas chromatograph main unit 301, crude product sampling tube 302, product sampling tube 303, sampling main pipe 304, reflux pipe 305, electrovaporizer 306, filter dehumidifier 307, first solenoid valve 308, second solenoid valve 309, pressure gauge 310, pressure regulating valve 311. Detailed Implementation

[0011] like Figure 1 As shown, an automatic sampling and analysis production control system for heptafluoroisopropyl bromide includes a reaction unit, a post-processing unit, a sampling and analysis unit, and a DCS control unit. The reaction unit includes a premixing vessel 103 and a reactor 104. The premixing vessel 103 is equipped with a bromine inlet pipe 101 and an organic fluoride inlet pipe 102 at its top. The premixing vessel 103 is connected to the reactor 104 through a mixed gas outlet pipe. The bromine gas and the organic fluoride gas are first mixed evenly in the premixing vessel 103, and then the mixed gas is introduced into the reactor 104 for heating to carry out a bromination reaction to generate a mixed gas of heptafluoroisopropylbromine crude product. The reactor 104 is equipped with an online thermometer 106 and an electric heating device 105. The online thermometer 106 and the electric heating device 105 are electrically connected to the DCS control unit.

[0012] The post-processing unit includes a water washing tower 201, an alkaline washing tower 202, a gas storage tank 203, a compressor 204, a crude product storage tank 205, and a distillation column 206 connected in sequence. The reactor 104 is connected in sequence to the water washing tower 201, the alkaline washing tower 202, the gas storage tank 203, and the compressor 204 via a heptafluoroisopropyl bromide crude product mixed gas pipeline. The compressor 204 is then connected in sequence to the crude product storage tank 205 and the distillation column 206 via a heptafluoroisopropyl bromide crude product liquid pipeline. A crude product pump 207 is installed on the connecting pipeline between the crude product storage tank 205 and the distillation column 206, and a transfer valve 208 is installed on the heptafluoroisopropyl bromide liquid outlet pipeline of the distillation column 206. The heptafluoroisopropyl bromide crude product mixed gas... After sequential washing in a water washing tower, alkali washing in an alkali washing tower, and compression by a compressor, a liquid crude product is obtained and sent to a crude product storage tank 205 for storage. The crude product storage tank 205 is equipped with an online level gauge, and the distillation column 206 is equipped with an online level gauge and an online thermometer. The online level gauge, online thermometer, crude product pump 207, and transfer valve 208 are electrically connected to the DCS control unit. When the material level in the crude product storage tank 205 and the distillation column 206 reaches the set value, the crude product pump 207 is turned on to send the liquid crude product into the distillation column 206 for heating and distillation to obtain heptafluoroisopropyl bromide product. When the liquid level in the distillation column and the concentration of heptafluoroisopropyl bromide in the product reach the control value, the transfer valve 208 is turned on to send the heptafluoroisopropyl bromide product out.

[0013] The sampling and analysis unit includes a gas chromatograph host 301, which is electrically connected to a DCS control unit. A crude product sampling tube 302 is located at the bottom of the crude product storage tank 205, and a product sampling tube 303 is located on the heptafluoroisopropyl bromide outlet line of the distillation column 206. The crude product sampling tube 302 and the product sampling tube 303 are combined into a sampling manifold 304, which is then connected to the gas chromatograph host 301. The gas chromatograph host 301 also has a sample reflux tube 305 connected to a gas storage tank 203. Both the crude product sampling tube 302 and the product sampling tube 303 are equipped with an electrovaporator 306 and a filter dehumidifier 307. The sample flowing out of the crude product storage tank 205 or the distillation column 206 is vaporized and dehumidified by the electrovaporator and then enters the gas chromatograph host 301 through the sampling main pipe 304 for analysis and detection. After the analysis is completed, the analysis data is transmitted to the DCS control unit, which controls the production system according to the analysis data. The analyzed sample is returned to the gas storage tank 203 through the reflux pipe 305.

[0014] The crude product sampling tube 302 is equipped with a first solenoid valve 308, and the product sampling tube 303 is equipped with a second solenoid valve 309; the solenoid valves are electrically connected to the DCS control unit; the DCS control unit controls the solenoid valves to operate by setting a program, and periodically switches between crude product and product sample gas to realize the cyclic measurement of two sample gases on one chromatography host.

[0015] The sampling manifold 304 is equipped with an online pressure gauge 310 and a pressure regulating valve 311, which are electrically connected to the DCS control unit. The DCS control unit adjusts the opening of the pressure regulating valve 311 according to the inlet pressure setting of the chromatography host, thereby ensuring the accuracy of the analytical data.

[0016] Both the crude product sampling tube 302 and the product sampling tube 303 have reflux branches connected to the gas storage tank 203 on the pipeline before the electrovaporizer 306 to maintain the fluidity of the sample, thereby ensuring the real-time nature and accuracy of the analytical data. The reflux lines are equipped with one-way valves to prevent sample backflow, which could affect the sampling and analysis results.

[0017] The working process of the above-mentioned automatic sampling and analysis production control system for heptafluoroisopropyl bromide is as follows: bromine gas and organic fluoride gas are fed into the premixing kettle 103 for premixing according to a set ratio, and then fed into the reactor 104 for heating and reaction at a set temperature to generate a crude heptafluoroisopropyl bromide product mixed gas. The mixed gas is washed with water, washed with alkali, compressed to liquid state, and then sent to the crude product storage tank 205. The crude product is then sent to the distillation column 206 for heating and distillation to obtain the heptafluoroisopropyl bromide product.

[0018] The feedback control program of the automatic sampling and analysis production control system includes the following steps: (1) The online chromatography control unit starts the sampling cycle.

[0019] (2) Open the first solenoid valve 308. The crude product sample 1 in the crude product storage tank 205 is heated and vaporized by the electrovaporator 306. After being dehydrated and impurities removed by the filter dehumidifier 307, it enters the gas chromatograph host 301 through the sampling main pipe 304 to replace the sample in the host. The replacement gas is returned to the gas storage tank 203. After 5 minutes of replacement, the chromatographic quantitative loop is filled and the chromatographic data acquisition begins. After 3 minutes, the sample is injected into the chromatographic column for data acquisition and analysis. After 5 minutes, the analysis ends and the first solenoid valve 308 is closed. During the sampling period, the sample gas pressure is controlled within the set range by the pressure regulating valve 311. (3) Open the second solenoid valve 309. The heptafluoroisopropyl bromide product sample 2 in the distillation column 206 is heated and vaporized by another set of electrovaporizers 306. After being dehydrated and impurities removed by the filter dehumidifier 307, it enters the gas chromatograph host 301 through the sampling manifold 304. Repeat step (2) to complete one sampling cycle. (4) After a 6-minute interval, proceed to the next sampling cycle; (5) When the concentration of sample 1 is lower than the set value, the electric heating device 105 is controlled by DCS to increase the reactor heating temperature; when the concentration of sample 1 is higher than the set value, the reactor heating temperature is reduced. (6) When the concentration of heptafluoroisopropyl bromide in sample 2 is higher than the control value and the liquid level of distillation column 206 is higher than the upper limit of the liquid level setting value, the transfer valve 208 on the discharge pipeline of distillation column is opened by DCS control to discharge heptafluoroisopropyl bromide. When the liquid level of distillation column 206 is lower than the lower limit of the liquid level setting value, the transfer valve 208 is closed. During this period, the temperature of the distillation column bottom is controlled at a constant temperature to prevent the light components from flowing back. (7) When the liquid level in crude product storage tank 205 is higher than the upper limit of the liquid level setting and the concentration of sample 1 is higher than the control value, crude product pump 207 is turned on by DCS control to send crude product to distillation column 206. When the liquid level in distillation column 206 exceeds the upper limit of the liquid level setting, crude product pump 207 is stopped. During this period, the temperature of the distillation column bottom is controlled within the distillation temperature setting range, and the column enters the distillation state.

[0020] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic sampling and analysis production control system for heptafluoroisopropyl bromide, characterized in that, It includes a reaction unit, a post-processing unit, a sampling and analysis unit, and a DCS control unit; The reaction unit includes a premixing vessel (103) and a reactor (104). The premixing vessel (103) is equipped with a bromine inlet pipe (101) and an organic fluoride inlet pipe (102) at the top. The premixing vessel (103) is also equipped with a mixed gas outlet pipe connected to the reactor (104). The reactor (104) is equipped with an online thermometer (106) and an electric heating device (105). The online thermometer (106) and the electric heating device (105) are electrically connected to the DCS control unit. The post-processing unit includes a water washing tower (201), an alkaline washing tower (202), a gas storage tank (203), a compressor (204), a crude product storage tank (205), and a distillation tower (206) connected in sequence. The reactor (104) is connected in sequence to the water washing tower (201), the alkaline washing tower (202), the gas storage tank (203), and the compressor (204) via a heptafluoroisopropyl bromide crude product gas pipeline. The compressor (204) is then connected in sequence to the crude product storage tank via a heptafluoroisopropyl bromide crude product liquid pipeline. (205) and distillation column (206), a crude product pump (207) is provided on the pipeline between the crude product storage tank (205) and the distillation column (206), a transfer valve (208) is provided on the heptafluoroisopropyl bromide outlet pipeline of the distillation column (206), an online level gauge is provided on the crude product storage tank (205), an online level gauge and an online thermometer are provided on the distillation column, and the online level gauge, online thermometer, crude product pump (207) and transfer valve (208) are electrically connected to the DCS control unit; The sampling and analysis unit includes a gas chromatograph main unit (301), which is electrically connected to the DCS control unit; a crude product sampling tube (302) is provided at the bottom of the crude product storage tank, and a product sampling tube (303) is provided on the heptafluoroisopropyl bromide outlet pipeline of the distillation column; the crude product sampling tube (302) and the product sampling tube (303) are combined into a sampling manifold (304) and then connected to the gas chromatograph main unit (301); The gas chromatograph host (301) is also equipped with a reflux pipe (305) connected to the gas storage tank (203). The crude product sampling pipe (302) and the product sampling pipe (303) are equipped with an electrovaporator (306) and a filter dehumidifier (307), which are used to vaporize, dehumidify and remove impurities from the sample flowing out of the crude product storage tank (205) or the distillation column (206) in sequence through the electrovaporator and then enter the gas chromatograph host (301) through the sampling main pipe (304).

2. The automatic sampling and analysis production control system for heptafluoroisopropyl bromide according to claim 1, characterized in that, The crude product sampling tube (302) is equipped with a first solenoid valve (308), and the product sampling tube (303) is equipped with a second solenoid valve (309); the solenoid valves (308, 309) are electrically connected to the DCS control unit.

3. The automatic sampling and analysis production control system for heptafluoroisopropyl bromide according to claim 1, characterized in that, The sampling manifold (304) is equipped with an online pressure gauge (310) and a pressure regulating valve (311), which are electrically connected to the DCS control unit. The DCS control unit adjusts the opening of the pressure regulating valve (311) according to the gas inlet pressure setting value of the chromatography host.

4. The automatic sampling and analysis production control system for heptafluoroisopropyl bromide according to claim 1, characterized in that, Both the crude product sampling tube (302) and the product sampling tube (303) have return branch pipes connected to the gas storage tank (203) on the pipeline before the electric vaporizer (306).

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