Liquid fuel component calibration method and system based on ideal gas state equation

Abstract

The invention discloses a liquid fuel component calibration method and system based on an ideal gas state equation, and belongs to the technical field of fuel analysis. The method is characterized by comprising the following steps: step a, monitoring and recording the mass flow rate and mass of liquid fuel and the mass flow rate of auxiliary gas; b, obtaining mixed gas; c, recording the total flow of the mixed gas; step d, obtaining the total mole number of the mixed gas; e, calculating the mole number of the liquid fuel in the mixed gas; f-g, constructing a linear relation model, and obtaining the molar mass of the liquid fuel; and step h, calculating to obtain the components of the liquid fuel. According to the liquid fuel component calibration method and system based on the ideal gas state equation, the functions of a liquid flowmeter and a gas calibration flowmeter are organically combined, and effective calibration of the molar mass and the chemical composition of the complex liquid fuel is achieved through application of the ideal gas state equation.

Description

Technical Field

[0001] The invention discloses a liquid fuel component calibration method and system based on an ideal gas state equation, belonging to the technical field of fuel analysis. Background Art

[0002] In the process of energy utilization and chemical production, it is crucial to accurately understand the chemical composition and molar mass of liquid fuels, because this is directly related to the combustion efficiency of the fuel, the environmental impact, and the design of subsequent processing technology. However, liquid fuels are often composed of a variety of complex hydrocarbons and other compounds, with diverse components and varying proportions, making accurate calibration a technical challenge.

[0003] Traditional methods for analyzing liquid fuel components mainly rely on complex chemical analysis methods, such as (1) chromatography (see the "Determination of oxygenated compounds in gasoline" mentioned in the Petrochemical Industry Standard of the People's Republic of China SH / T0720-2002). (2) Mass spectrometry (see the method described in the document "Qualitative and quantitative analysis of catalytic cracking gasoline by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry"), etc. Although these methods can accurately analyze the components of liquid fuels, they are cumbersome and time-consuming to operate, and are somewhat destructive to samples, which is not conducive to rapid and continuous monitoring needs. In addition, these methods often focus on the analysis of a single component and are difficult to fully reflect the overall chemical composition of the fuel. This directly affects the setting of combustion parameters and the optimization of combustion efficiency. Therefore, designing a technical solution that can accurately calibrate the components of liquid fuels has become an urgent problem to be solved in this field. Summary of the invention

[0004] The technical problem to be solved by the present invention is: to overcome the shortcomings of the prior art and provide a liquid fuel component calibration method and machine calibration system that organically combines the functions of a liquid flow meter and a gas calibration flow meter, and through the application of the ideal gas state equation, realizes an effective calibration of the molar mass and chemical composition of complex liquid fuels based on the ideal gas state equation.

[0005] The technical solution adopted by the present invention to solve the technical problem is: the liquid fuel component calibration method based on the ideal gas state equation is characterized by comprising the following steps: Step a, monitoring and recording the mass flow rate of liquid fuel and the mass of liquid fuel at any time m Fuel , and the mass flow rate of the auxiliary gas; Step b, mixing the liquid fuel with the auxiliary gas and gasifying them to obtain a mixed gas; Step c, record the total flow rate of the mixed gas Q Flow-sum ; Step d, apply the ideal gas state equation to convert the total flow rate of the mixed gas Q Flow-sum Convert to the corresponding total number of moles n sum ; Step e: Calculate the number of moles of liquid fuel in the mixed gas at the current moment n Fuel , and the number of moles n Fuel As a data point; Step f, looping through steps a to e to obtain a number of data points at different times; Step g, based on all data points, construct m Fuel and n Fuel The linear relationship model between them is used to obtain the molar mass of the liquid fuel; Step h: Calculate and obtain the components of the liquid fuel.

[0006] Preferably, in step g, the molar mass of the liquid fuel is obtained according to the slope of the linear relationship model.

[0007] Preferably, in step g, a linear relationship model is constructed by least squares method.

[0008] Preferably, in step e, from the sum of the molar numbers n sum Subtract the known number of moles of nitrogen from n N2 , get the number of moles of liquid fuel in the mixed gas at the current moment n Fuel .

[0009] Preferably, in step a, the auxiliary gas is nitrogen.

[0010] A liquid fuel component calibration system based on an ideal gas state equation is characterized by comprising a gas storage tank for placing auxiliary gas and a liquid storage tank for placing liquid fuel, the gas storage tank is connected to a gas mass flow controller, the gas storage tank is simultaneously connected to a liquid storage tank, the outlet of the liquid storage tank is connected to a liquid flow controller, the outlet of the gas mass flow controller and the outlet of the liquid flow controller are simultaneously connected to a controllable evaporation mixer, and the controllable evaporation mixer is connected to a gas flow meter.

[0011] Preferably, a first valve is provided between the gas storage bottle and the liquid storage bottle, and a second valve is provided between the liquid storage tank and the liquid mass flow controller.

[0012] Compared with the prior art, the present invention has the following beneficial effects: In this liquid fuel component calibration method and machine calibration system based on the ideal gas state equation, the functions of the liquid flow meter and the gas calibration flow meter are organically combined. Through the application of the ideal gas state equation, the effective calibration of the molar mass and chemical composition of complex liquid fuels is achieved.

[0013] This liquid fuel component calibration method and machine calibration system based on the ideal gas state equation not only improves the accuracy of fuel component determination, but also simplifies the measurement process and reduces the difficulty of operation. At the same time, combined with the chemical composition information of the fuel, it can more accurately set the combustion parameters, optimize the combustion process, improve energy efficiency, and ensure the safe operation of the system.

[0014] This liquid fuel component calibration method based on the ideal gas state equation machine calibration system proposes an indirect calibration method based on physical principles, in which the ideal gas state equation has obvious advantages due to its simplicity and universality. The ideal gas state equation can describe the relationship between gas state parameters (such as pressure, volume, temperature, and molar number). By reasonably designing experimental conditions, liquid fuel can be converted into a gaseous mixture, and then the equation can be used for component analysis.

[0015] This liquid fuel component calibration method and system based on the ideal gas state equation aims to combine the functions of the liquid flow meter and the gas calibration flow meter, and use the principle of the ideal gas state equation to achieve effective, rapid and non-destructive calibration of the molar mass and chemical composition of complex liquid fuels, so as to meet the needs of the energy and chemical industries for accurate analysis of liquid fuel components. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The figure is a flow chart of the liquid fuel composition calibration method based on the ideal gas state equation.

[0017] Figure 2 This is the principle block diagram of the liquid fuel composition calibration system based on the ideal gas state equation. DETAILED DESCRIPTION

[0018] Figure 1~2 The best embodiment of the present invention is shown below in conjunction with the attached Figure 1~2 The present invention is further described.

[0019] Embodiment 1: like Figure 1 As shown, the liquid fuel component calibration method based on the ideal gas state equation includes the following steps: Step 1001, monitoring and recording the mass flow of gas and liquid fuel; Use liquid mass flow controllers to monitor and record the mass flow of liquid fuel in real time Q Fuel, to determine the mass of liquid fuel at any time m Fuel At the same time, the nitrogen flow mass controller is used to monitor and record the nitrogen mass flow in real time. Q N2 .

[0020] Step 1002, mixing and converting the liquid fuel into a gaseous state; The liquid fuel is mixed with nitrogen with a known flow rate to form a gas-liquid mixture, and the gas-liquid mixture is converted into a gaseous state by a controllable evaporation mixer to obtain a mixed gas, in which the molar number of nitrogen is n N2 At a given time, the mass flow rate is known. Q N2 get.

[0021] Step 1003, recording the total flow rate of the mixed gas; Use a gas flow meter to record the total flow of the mixed gas Q Flow-sum .

[0022] Step 1004, converting the mole number of the mixed gas; Apply the ideal gas state equation to calculate the total flow rate of the mixed gas Q Flow-sum Convert to the corresponding total number of moles n sum .

[0023] Step 1005, calculating the number of moles of liquid fuel in the mixed gas; From the total number of moles n sum Subtract the known number of moles of nitrogen from n N2 , to calculate the number of moles of liquid fuel in the mixed gas at the current moment n Fuel , the number of moles n Fuel As a data point.

[0024] Step 1006, determining whether a data point has been reached; Determine whether the number of data points collected in step 1005 has reached the preset collection number. If it has reached the preset collection number, execute step 1007. If it has not yet reached the preset collection number, return to step 1001 and execute steps 1001 to 1005 at another time to obtain data points at another time.

[0025] Step 1007, calculating the molar mass of the liquid fuel; Based on the collected data points, statistical and mathematical methods are used to constructm Fuel and n Fuel A linear relationship model is formed between , where the slope of the linear relationship model reflects the molar mass of the liquid fuel.

[0026] In this step, the linear relationship model can be constructed by the least square method or other mathematical optimization methods to improve the accuracy and reliability of the model.

[0027] Step 1008, calculating and obtaining the components of the liquid fuel; After executing step 1007, the specific chemical composition (C:H:O) of the fuel can be further determined by combining key parameters such as the hydrogen-to-carbon ratio (H / C) and oxygen content of the fuel through a chemometric method and using the linear relationship model, and the equivalent ratio of the liquid fuel can be accurately calculated.

[0028] Implement the calibration system of steps 1001 to 1007 above, such as Figure 2 As shown, it includes a nitrogen bottle and a liquid storage tank, the nitrogen bottle is filled with nitrogen, and the liquid storage tank contains the above-mentioned liquid fuel. One end of the outlet of the nitrogen bottle is connected to a gas mass flow controller, and the nitrogen flow rate is controlled by the gas mass flow controller. The other end is connected to the liquid storage tank through a first valve, and the pressure of nitrogen is used to push the liquid fuel in the liquid storage tank to be output, and this part of the nitrogen is used as a power gas to push the liquid fuel to be output, and is not output together with the liquid fuel.

[0029] The output end of the liquid storage tank is connected to the liquid mass flow controller through the second valve, and the mass flow rate of the liquid fuel is monitored and recorded by the liquid mass flow controller. Q Fuel The output ends of the liquid mass flow controller and the gas mass flow controller are simultaneously connected to the input end of the controllable evaporation mixer, and the liquid fuel is converted into gaseous state through the controllable evaporation mixer, and mixed with the nitrogen sent by the gas mass flow controller to obtain the above-mentioned mixed gas. The output end of the controllable evaporation mixer is connected to the gas flow meter, and the total flow of the mixed gas is recorded by the gas flow meter. Q Flow-sum .

[0030] The specific calibration process and principle are as follows: Open the first valve and the second valve, and open the nitrogen bottle at the same time. After the nitrogen bottle is opened, one path directly enters the gas mass flow controller, and the other path passes through the first valve to enter the liquid storage tank. The liquid storage tank contains the liquid fuel to be tested. The nitrogen entering the gas mass flow controller is monitored by the mass flow controller and its mass flow is recorded Q N2The nitrogen entering the liquid storage tank through the first valve is used as a power gas to push the liquid fuel in the liquid storage tank to be output.

[0031] The liquid fuel output from the liquid storage tank enters the liquid mass flow controller through the second valve, and the liquid mass flow controller is used to monitor and record the mass flow of the liquid fuel in real time. Q Fuel , to determine the mass of liquid fuel at any time m Fuel The nitrogen output by the gas mass flow controller and the liquid fuel output by the liquid mass flow controller are simultaneously sent to the controllable evaporation mixer, which gasifies the liquid fuel and mixes it with the nitrogen to obtain a mixed gas. After the mixed gas is output by the controllable evaporation controller, it enters the gas flow meter, which records the total flow of the mixed gas. Q Flow-sum .

[0032] Apply the ideal gas state equation to calculate the total flow rate of the mixed gas Q Flow-sum Convert to the corresponding total number of moles n sum , due to the molar number of nitrogen n N2 The same is known at a given time, so from the sum of the moles n sum Subtract the known number of moles of nitrogen from n N2 , to calculate the number of moles of liquid fuel in the mixed gas at the current moment n Fuel , the number of moles n Fuel As a data point. After obtaining enough data points, construct m Fuel and n Fuel A linear relationship model is developed between the two, where the slope of the linear relationship model reflects the molar mass of the liquid fuel. Finally, through the key parameters of the fuel such as the hydrogen-to-carbon ratio (H / C) and oxygen content, the linear relationship model is used to further determine the specific chemical composition (C:H:O) of the fuel through chemometric methods, and the equivalent ratio of the fuel is accurately calculated.

[0033] Embodiment 2: The difference between this embodiment and embodiment 1 is that the liquid fuel in the liquid storage tank is a known fuel, such as n-heptane, and steps 1001 to 1008 in embodiment 1 are executed to obtain the calculated value of the molar mass of the liquid fuel. Since the liquid fuel is a known fuel, the calculated value of the molar mass of the liquid fuel is compared with the theoretical value of the molar mass of the liquid fuel to evaluate the measurement error of the gas flow meter.

[0034] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A liquid fuel component calibration method based on an ideal gas state equation, characterized in that: The steps include: Step a, monitoring and recording the mass flow rate of liquid fuel and the mass of liquid fuel at any time m Fuel , and the mass flow rate of the auxiliary gas; Step b, mixing the liquid fuel with the auxiliary gas and gasifying them to obtain a mixed gas; Step c, record the total flow rate of the mixed gas Q Flow-sum ; Step d, apply the ideal gas state equation to calculate the total flow rate of the mixed gas Q Flow-sum Convert to the corresponding total number of moles n sum ; Step e: Calculate the number of moles of liquid fuel in the mixed gas at the current moment n Fuel , and the number of moles n Fuel As a data point; Step f, looping through steps a to e to obtain a number of data points at different times; Step g, based on all data points, construct m Fuel and n Fuel The linear relationship model between them is used to obtain the molar mass of the liquid fuel; Step h: Calculate and obtain the components of the liquid fuel.

2. The liquid fuel component calibration method based on the ideal gas state equation according to claim 1 is characterized in that: In step g, the molar mass of the liquid fuel is obtained according to the slope of the linear relationship model.

3. The liquid fuel component calibration method based on the ideal gas state equation according to claim 1 or 2, characterized in that: In step g, a linear relationship model is constructed by the least squares method.

4. The liquid fuel component calibration method based on the ideal gas state equation according to claim 1 or 2, characterized in that: In step e, from the sum of the moles n sum Subtract the known number of moles of nitrogen from n N2 , get the number of moles of liquid fuel in the mixed gas at the current moment n Fuel .

5. The liquid fuel component calibration method based on the ideal gas state equation according to claim 1 is characterized in that: In step a, the auxiliary gas is nitrogen.

6. A system for implementing the liquid fuel component calibration method based on the ideal gas state equation as described in any one of claims 1 to 5, characterized in that: It includes a gas storage tank for placing auxiliary gas and a liquid storage tank for placing liquid fuel. The gas storage tank is connected to a gas mass flow controller, and the gas storage tank is also connected to a liquid storage tank. The outlet of the liquid storage tank is connected to the liquid flow controller. The outlet of the gas mass flow controller and the outlet of the liquid flow controller are simultaneously connected to a controllable evaporation mixer, and the controllable evaporation mixer is connected to a gas flow meter.

7. The system according to claim 6, characterized in that: A first valve is arranged between the gas storage bottle and the liquid storage bottle, and a second valve is arranged between the liquid storage tank and the liquid mass flow controller.

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