A control system for preventing temperature runaway of gas chromatograph

Abstract

The present invention relates to the technical field of gas chromatographs, and discloses a control system for preventing temperature runaway of a gas chromatograph, comprising a carrier gas bottle flow rate monitoring module, a detector, a sample weight measurement module, a data recording module, a data analysis module, a chromatographic furnace sensor, a control module, a chromatographic furnace temperature regulator, and a carrier gas bottle flow rate valve; the data recording module is used to record the data collected by the carrier gas bottle flow rate monitoring module, the detector, and the sample weight measurement module, and to display the recorded data in real time; the chromatographic furnace sensor is used to collect temperature information in the chromatographic furnace and temperature information of a carrier coating fixing liquid. The present invention introduces the difference between the weight reduction of a sample to be tested and the amount of volatile organic compounds passing through as an intervention factor, thereby allowing a temperature regulator to regulate the temperature in the chromatographic furnace. This regulation method can allow the temperature of the chromatographic column to approach the optimal conversion temperature of the sample to be tested.

Description

Technical Field

[0001] The invention relates to the technical field of gas chromatographs, and in particular to a control system for preventing temperature runaway of a gas chromatograph. Background Art

[0002] Gas chromatograph is a laboratory instrument widely used to separate and analyze gas samples. It separates complex gas mixtures into different components by utilizing the distribution differences between the stationary phase and the mobile phase, and can perform qualitative and quantitative analysis on these components.

[0003] The existing patent discloses a gas chromatograph column box temperature control method (CN117826904A), which includes the following steps: according to the temperature value in the column box collected by the temperature measuring element and the preset corresponding temperature rise control parameters, control the heating element to heat the column box; after the temperature in the column box reaches the initial set temperature, according to the preset separation temperature of different gas components in the sample in the column box, determine multiple target temperatures and the control parameters required to reach the corresponding target temperature; determine the target temperature corresponding to the temperature value at the current moment. In the technology disclosed in this patent, after setting the approximate analysis temperature for the sample to be tested, due to the different component contents and the different masses of the sample to be tested, this will cause the temperature set for the gas chromatograph to be inconsistent with the actual optimal conversion temperature (such as Figure 3 This will reduce the analytical efficiency of the gas chromatograph. Summary of the invention

[0004] The main technical problem solved by the present invention is to provide a control system for preventing temperature runaway of a gas chromatograph, thereby solving the problems in the above-mentioned background technology.

[0005] To solve the above technical problems, according to one aspect of the present invention, more specifically, a control system for preventing temperature runaway of a gas chromatograph comprises a carrier gas bottle flow rate monitoring module, a detector, a sample weight measurement module, a data recording module, a data analysis module, a chromatographic furnace sensor, a control module, a chromatographic furnace temperature regulator and a carrier gas bottle flow rate valve;

[0006] The data recording module is used to record the data collected by the carrier gas bottle flow rate monitoring module, the detector and the sample weight measurement module, and to display the recorded data in real time;

[0007] The chromatographic furnace sensor is used to collect temperature information in the chromatographic furnace, temperature information of the carrier coating fixing liquid, and gas flow rate information in the chromatographic column, and feed the collected information back to the data analysis module;

[0008] The data analysis module dynamically adjusts the temperature in the chromatographic furnace and the gas flow rate of the carrier gas bottle according to the data fed back by the chromatographic furnace sensor and the data recording module;

[0009] The control module is used to adjust the chromatographic furnace temperature regulator and the carrier gas bottle flow rate valve according to the analysis results of the data analysis module.

[0010] Furthermore, the chromatographic furnace sensor specifically includes: a temperature sensor in the chromatographic furnace, a carrier coating stationary liquid temperature sensor and a flow rate sensor in the chromatographic column;

[0011] The temperature sensor in the chromatographic furnace is used to detect the temperature in the chromatographic furnace in real time and feed back the temperature information in the furnace to the data analysis module;

[0012] The carrier coating fixing liquid temperature sensor is used to detect the carrier fixing liquid temperature at the inner wall of the chromatographic column in real time and feed back the detected temperature information to the data analysis module;

[0013] The flow velocity sensor in the chromatographic column is used to detect the actual flow velocity of the flowing gas in the chromatographic column in real time, and feed back the velocity information to the data analysis module.

[0014] Furthermore, the data analysis module determines whether it is necessary to increase or decrease the temperature in the chromatographic oven according to the influence of the temperature in the chromatographic oven, the influence of the gas flow rate in the chromatographic column, the weight of the sample to be measured prevented by the sample weight measurement module, and the amount of volatile organic compounds detected by the detector, as follows:

[0015] ;

[0016] In the formula, Indicates the control index coefficient of the temperature in the chromatographic furnace; Indicates the influence coefficient of the color column and furnace temperature on this regulation; Indicates the influence coefficient of the state of nitrogen in the chromatographic column on this regulation; It indicates the reduction of the sample weight in the vaporization chamber in 30 seconds; Indicates the amount of volatile organic compounds detected by the detector within 30 seconds;

[0017] then, This means that the control module needs to lower the temperature in the chromatographic oven, and the maximum temperature reduction each time shall not exceed 50 degrees Celsius, and the interval time for each temperature reduction shall not exceed 40 seconds;

[0018] then, This means that the control module needs to increase the temperature in the chromatographic oven, and the maximum value of each temperature increase shall not exceed 50 degrees Celsius, and the interval time of each temperature increase shall not exceed 30 seconds.

[0019] Furthermore, the data analysis module determines the influence of the temperature of the chromatographic column and the temperature in the furnace on the data analysis according to the temperature difference between the chromatographic furnace and the chromatographic column, the heating rate of the chromatographic furnace and the heating rate of the chromatographic column, as follows:

[0020] ;

[0021] In the formula, Indicates the influence coefficient of the color column and furnace temperature on this regulation; Indicates the temperature difference between the chromatographic oven and the chromatographic column; Indicates the heating rate of the chromatographic furnace; Indicates the temperature rise rate of the chromatographic column.

[0022] Furthermore, the data analysis module determines the influence of the nitrogen state on the data analysis according to the nitrogen flow rate monitoring module of the carrier gas bottle within 30 seconds and the nitrogen flow rate detected by the detector within the same 30 seconds, which are:

[0023] ;

[0024] In the formula, Indicates the influence coefficient of the state of nitrogen in the chromatographic column on this regulation; Indicates the average purity of nitrogen recorded by the carrier gas bottle flow rate monitoring module within 30 seconds; It indicates the average purity of nitrogen detected by the detector within the same 30 seconds.

[0025] Furthermore, the chromatographic oven temperature regulator can increase or decrease the temperature in the chromatographic oven.

[0026] Furthermore, the carrier gas bottle flow rate valve can increase or decrease the flow rate of the gas injected from the carrier gas bottle into the vaporization chamber.

[0027] Furthermore, the carrier gas bottle flow rate monitoring module is used to detect the speed and concentration of nitrogen injected into the gasification chamber by the carrier gas bottle in real time, and feed back the detected speed information and concentration information to the data recording module in real time.

[0028] Furthermore, the detector is used to detect the concentration of nitrogen and the concentration of volatile organic compounds in the exhaust gas.

[0029] Furthermore, the sample weight measurement module is used to detect the weight of the sample to be tested put into the gasification chamber, and feed back the weight information to the data recording module.

[0030] Beneficial effects:

[0031] 1. The present invention introduces the difference between the weight reduction of the sample to be tested and the amount of volatile organic compounds passing through as an intervention factor, thereby allowing the temperature regulator to regulate the temperature in the chromatographic furnace. This regulation method can make the temperature of the chromatographic column approach the optimal conversion temperature of the sample to be tested.

[0032] 2. The present invention determines the influence of the nitrogen state on data analysis by recording the nitrogen flow rate of the carrier gas bottle within 30 seconds and the nitrogen flow rate detected by the detector within the same 30 seconds, which can further improve the accuracy of adjusting the temperature to the optimal conversion temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the present invention;

[0034] Figure 2 is a flow chart of the present invention;

[0035] Figure 3 In the above figure, a represents the control method without introducing any intervening factors, and b represents the control method with introducing any intervening factors. DETAILED DESCRIPTION

[0036] In order to make the technical solution of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1

[0038] like Figure 1 - 2, according to one aspect of the present invention, a control system for preventing temperature runaway of a gas chromatograph is provided, comprising a carrier gas bottle flow rate monitoring module, a detector, a sample weight measurement module, a data recording module, a data analysis module, a chromatographic furnace sensor, a control module, a chromatographic furnace temperature regulator and a carrier gas bottle flow rate valve. Figure 1 As shown, the controller is internally integrated with a control module and a data analysis module; the flow meter includes a carrier gas bottle flow rate monitoring module and a carrier gas bottle flow rate valve; the sensor is the chromatographic furnace sensor; the recording module is the data recording module; the sample weight measurement module is located inside the vaporization chamber; the temperature regulator is the chromatographic furnace temperature regulator; the carrier gas in the carrier gas bottle is nitrogen.

[0039] The data recording module is used to record the data collected by the carrier gas bottle flow rate monitoring module, the detector and the sample weight measurement module, and to display the recorded data in real time; the chromatographic furnace sensor is used to collect the temperature information in the chromatographic furnace, the temperature information of the carrier coating fixing liquid and the gas flow rate information in the chromatographic column, and to feed back the collected information to the data analysis module; the data analysis module dynamically adjusts the temperature in the chromatographic furnace and the gas outlet flow rate of the carrier gas bottle according to the data fed back by the chromatographic furnace sensor and the data recording module; the control module is used to adjust the chromatographic furnace temperature regulator and the carrier gas bottle flow rate valve according to the analysis results of the data analysis module. By introducing the difference between the reduction in the weight of the sample to be tested and the amount of volatile organic compounds passing through as an intervention factor, the temperature regulator is used to adjust the temperature in the chromatographic furnace. This control method can make the temperature of the chromatographic column approach the optimal conversion temperature of the sample to be tested (such as Figure 3 b).

[0040] In this embodiment, the chromatographic furnace sensor specifically includes: a temperature sensor inside the chromatographic furnace, a carrier coating fixed liquid temperature sensor and a flow rate sensor inside the chromatographic column; the temperature sensor inside the chromatographic furnace is used to detect the temperature inside the chromatographic furnace in real time, and feed back the temperature information inside the furnace to the data analysis module; the carrier coating fixed liquid temperature sensor is used to detect the carrier fixed liquid temperature at the inner wall of the chromatographic column in real time, and feed back the detected temperature information to the data analysis module; the flow rate sensor inside the chromatographic column is used to detect the actual flow velocity of the flowing gas in the chromatographic column in real time, and feed back the velocity information to the data analysis module.

[0041] Example 2

[0042] The data analysis module determines whether it is necessary to increase or decrease the temperature in the chromatographic oven according to the temperature influence in the chromatographic oven, the influence of the gas flow rate in the chromatographic column, the weight of the sample to be measured prevented by the sample weight measurement module, and the amount of volatile organic compounds detected by the detector.

[0043] ;

[0044] In the formula, Indicates the control index coefficient of the temperature in the chromatographic furnace; Indicates the influence coefficient of the color column and furnace temperature on this regulation; Indicates the influence coefficient of the state of nitrogen in the chromatographic column on this regulation; It indicates the reduction of the sample weight in the vaporization chamber in 30 seconds; Indicates the amount of volatile organic compounds detected by the detector within 30 seconds;

[0045] then, This means that the control module needs to lower the temperature in the chromatographic oven, and the maximum temperature reduction each time shall not exceed 50 degrees Celsius, and the interval time for each temperature reduction shall not exceed 40 seconds;

[0046] then, This means that the control module needs to increase the temperature in the chromatographic oven, and the maximum value of each temperature increase shall not exceed 50 degrees Celsius, and the interval time of each temperature increase shall not exceed 30 seconds.

[0047] In this embodiment, the data analysis module determines the temperature of the chromatographic column and the influence of the temperature in the furnace on the data analysis according to the temperature difference between the chromatographic furnace and the chromatographic column, the heating rate of the chromatographic furnace and the heating rate of the chromatographic column, which are:

[0048] ;

[0049] In the formula, Indicates the influence coefficient of the color column and furnace temperature on this regulation; Indicates the temperature difference between the chromatographic oven and the chromatographic column; Indicates the heating rate of the chromatographic furnace; Indicates the temperature rise rate of the chromatographic column.

[0050] In this embodiment, the data analysis module determines the influence of the nitrogen state on the data analysis based on the nitrogen flow rate monitoring module recorded by the carrier gas bottle within 30 seconds and the nitrogen flow rate detected by the detector within the same 30 seconds, which are:

[0051] ;

[0052] In the formula, Indicates the influence coefficient of the state of nitrogen in the chromatographic column on this regulation; Indicates the average purity of nitrogen recorded by the carrier gas bottle flow rate monitoring module within 30 seconds; It indicates the average purity of nitrogen detected by the detector within the same 30 seconds.

[0053] Then, when testing any sample to be tested, the average purity of nitrogen recorded by the carrier gas bottle flow rate monitoring module within 30 seconds is The average purity of nitrogen detected by the detector in the same 30 seconds is , then we have:

[0054] ;

[0055] From the above calculation, we can know that the influence coefficient of the state of nitrogen in the chromatographic column on this regulation is .

[0056] Then, when testing any sample, the temperature difference between the chromatographic furnace and the chromatographic column is The heating rate of the chromatographic furnace is The heating rate of the chromatographic column is , then we have:

[0057] ;

[0058] From the above calculation, we can know that the influence coefficient of the color column and the temperature in the furnace on this regulation is .

[0059] Among them, when testing the oil sample to be tested, the weight reduction of the oil sample in the vaporization chamber in 30 seconds is (g), the amount of all volatile organic compounds detected by the detector within 30 seconds is taken (grams, where petroleum volatile organic matter includes alkanes, cycloalkanes, aromatic hydrocarbons and olefins), then:

[0060] ;

[0061] From the above calculation, it can be known that the control module needs to lower the temperature in the chromatographic oven, and the maximum value of each temperature reduction does not exceed 50 degrees Celsius, and the interval time of each temperature reduction does not exceed 40 seconds.

[0062] By comparing different samples of oil, there are:

[0063] From the above table, we can see that when When , it means that the control module needs to lower the temperature in the chromatographic oven; when , it indicates that the control module needs to increase the temperature in the chromatographic oven.

[0064] In this embodiment, the chromatographic oven temperature regulator can increase or decrease the temperature in the chromatographic oven. The carrier gas bottle flow rate valve can increase or decrease the flow rate of the gas injected from the carrier gas bottle into the vaporization chamber. The carrier gas bottle flow rate monitoring module is used to detect the speed and concentration of nitrogen injected from the carrier gas bottle into the vaporization chamber in real time, and feed back the detected speed information and concentration information to the data recording module in real time. The detector is used to detect the concentration of nitrogen and the concentration of volatile organic compounds in the exhaust gas. The sample weight measurement module is used to detect the weight of the sample to be tested put into the vaporization chamber, and feed back the weight information to the data recording module.

[0065] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A control system for preventing temperature runaway of a gas chromatograph, characterized in that: It includes a carrier gas bottle flow rate monitoring module, a detector, a sample weight measurement module, a data recording module, a data analysis module, a chromatographic furnace sensor, a control module, a chromatographic furnace temperature regulator and a carrier gas bottle flow rate valve; The data recording module is used to record the data collected by the carrier gas bottle flow rate monitoring module, the detector and the sample weight measurement module, and to display the recorded data in real time; The chromatographic furnace sensor is used to collect temperature information in the chromatographic furnace, temperature information of the carrier coating fixing liquid, and gas flow rate information in the chromatographic column, and feed the collected information back to the data analysis module; The chromatographic furnace sensor specifically includes: a temperature sensor in the chromatographic furnace, a carrier coating stationary liquid temperature sensor and a flow rate sensor in the chromatographic column; The temperature sensor in the chromatographic furnace is used to detect the temperature in the chromatographic furnace in real time and feed back the temperature information in the furnace to the data analysis module; The carrier coating fixing liquid temperature sensor is used to detect the carrier fixing liquid temperature at the inner wall of the chromatographic column in real time and feed back the detected temperature information to the data analysis module; The flow velocity sensor in the chromatographic column is used to detect the actual flow velocity of the gas flowing in the chromatographic column in real time and feed the velocity information back to the data analysis module; The data analysis module dynamically adjusts the temperature in the chromatographic furnace and the gas flow rate of the carrier gas bottle according to the data fed back by the chromatographic furnace sensor and the data recording module; The control module is used to adjust the chromatographic furnace temperature regulator and the carrier gas bottle flow rate valve according to the analysis results of the data analysis module; The data analysis module determines whether it is necessary to increase or decrease the temperature in the chromatographic oven according to the temperature influence in the chromatographic oven, the influence of the gas flow rate in the chromatographic column, the weight of the sample to be tested measured by the sample weight measurement module, and the amount of volatile organic compounds detected by the detector, as follows: ； In the formula, Indicates the control index coefficient of the temperature in the chromatographic furnace; Indicates the influence coefficient of the chromatographic column and furnace temperature on this regulation; Indicates the influence coefficient of the state of nitrogen in the chromatographic column on this regulation; It indicates the reduction of the sample weight in the vaporization chamber in 30 seconds; Indicates the amount of volatile organic compounds detected by the detector within 30 seconds; when When , it means that the control module needs to lower the temperature in the chromatographic oven, and the maximum value of each temperature reduction shall not exceed 50 degrees Celsius, and the interval time of each temperature reduction shall not exceed 40 seconds; when When , it means that the control module needs to increase the temperature in the chromatographic oven, and the maximum value of each temperature increase shall not exceed 50 degrees Celsius, and the interval time of each temperature increase shall not exceed 30 seconds.

2. The control system for preventing temperature runaway of a gas chromatograph according to claim 1, characterized in that: The data analysis module determines the influence of the temperature of the chromatographic column and the temperature in the furnace on the data analysis according to the temperature difference between the chromatographic furnace and the chromatographic column, the heating rate of the chromatographic furnace and the heating rate of the chromatographic column, as follows: ； In the formula, Indicates the influence coefficient of the chromatographic column and furnace temperature on this regulation; Indicates the temperature difference between the chromatographic oven and the chromatographic column; Indicates the heating rate of the chromatographic furnace; Indicates the temperature rise rate of the chromatographic column.

3. The control system for preventing temperature runaway of a gas chromatograph according to claim 2, characterized in that: The data analysis module determines the influence of the nitrogen state on the data analysis based on the nitrogen flow rate monitoring module of the carrier gas bottle within 30 seconds and the nitrogen flow rate detected by the detector within the same 30 seconds, which are: ； In the formula, Indicates the influence coefficient of the state of nitrogen in the chromatographic column on this regulation; Indicates the average purity of nitrogen recorded by the carrier gas bottle flow rate monitoring module within 30 seconds; It indicates the average purity of nitrogen detected by the detector within the same 30 seconds.

4. The control system for preventing temperature runaway of a gas chromatograph according to claim 1, characterized in that: The chromatographic oven temperature regulator can increase or decrease the temperature in the chromatographic oven.

5. The control system for preventing temperature runaway of a gas chromatograph according to claim 1, characterized in that: The carrier gas bottle flow rate valve can increase or decrease the flow rate of the gas injected from the carrier gas bottle into the vaporization chamber.

6. The control system for preventing temperature runaway of a gas chromatograph according to claim 1, characterized in that: The carrier gas bottle flow rate monitoring module is used to detect the speed and concentration of nitrogen injected into the gasification chamber by the carrier gas bottle in real time, and feed back the detected speed information and concentration information to the data recording module in real time.

7. The control system for preventing temperature runaway of a gas chromatograph according to claim 1, characterized in that: The detector is used to detect the concentration of nitrogen and the concentration of volatile organic compounds in the exhaust gas.

8. The control system for preventing temperature runaway of a gas chromatograph according to claim 1, characterized in that: The sample weight measurement module is used to detect the weight of the sample to be tested put into the gasification chamber, and feed back the weight information to the data recording module.

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