A laboratory flasher for liquefied petroleum gas composition determination

Abstract

The utility model discloses a laboratory is used for the flash evaporation appearance of liquefied petroleum gas composition determination, including buffer tank, the front side wall center of buffer tank is fixedly connected with the gas path connecting pipe, the other end flange of gas path connecting pipe is connected with pressure -reducing valve, and the other end fixed connection of gas outlet gas path pipe has gas outlet gas path structure, and the outer wall opposite side of buffer tank is fixedly connected with heating assembly. The utility model discloses through the rational setting heating assembly, respectively carries out heating and heat tracing to buffer tank and pressure -reducing valve, ensures that the normal octane of the highest boiling point in liquefied petroleum gas can fully vaporize, and satisfies 100 DEG C's working temperature requirement, adopts high -performance R23 series stainless steel pressure -reducing valve simultaneously, realizes the instantaneous stable decompression of sample pressure, guarantees that all components are instantaneous and vaporize simultaneously, effectively improves the sample injection repeatability, through setting up the flow rate control assembly of needle valve and flowmeter composition, can accurate control sample outlet flow rate, avoids the influence detection result because of unstable flow rate.

Description

Technical Field

[0001] This utility model relates to the field of laboratory analysis and testing equipment technology, specifically to a laboratory flash evaporator for determining the composition of liquefied petroleum gas. Background Technology

[0002] In laboratory testing of the composition of liquefied petroleum gas (LPG), gas chromatography is commonly used. The flash evaporator, as a key piece of equipment in the gas chromatography process, directly affects the accuracy and reliability of the test results. According to clause 5.5.2 of NB / SH / T0230-2019 "Determination of Composition of Liquefied Petroleum Gas - Gas Chromatography," the flash evaporator must meet the requirements of injection repeatability ≤4% and be able to withstand a liquid injection pressure of 1380 kPa at an operating temperature of 100℃.

[0003] Existing flash evaporation equipment suffers from several drawbacks in practical applications, including low vaporization efficiency, unstable pressure control, and poor temperature adaptability. For example, some equipment cannot achieve simultaneous instantaneous vaporization of all components, leading to inaccurate test results; some pressure-regulating valves struggle to maintain stable pressure regulation under high-temperature and high-pressure environments and lack sufficient corrosion resistance, affecting equipment lifespan; furthermore, the gas path design of existing equipment is inadequate, easily resulting in sample residue and inaccurate flow rate control, further reducing the repeatability and accuracy of test data and failing to meet the demands of high-precision laboratory testing. Therefore, there is an urgent need to develop a laboratory flash evaporator that meets standard requirements and offers stable and reliable performance. Utility Model Content

[0004] The purpose of this invention is to provide a laboratory flash evaporator for determining the composition of liquefied petroleum gas, in order to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a laboratory flash evaporator for determining the composition of liquefied petroleum gas, comprising a buffer tank, a gas connection pipe fixedly connected to the center of the front side wall of the buffer tank, a pressure reducing valve connected to the flange at the other end of the gas connection pipe, an adjusting knob connected to the flange on the other side of the pressure reducing valve, an outlet gas pipe fixedly connected to one side of the outer wall of the buffer tank, an outlet gas structure fixedly connected to the other end of the outlet gas pipe, and a heating component fixedly connected to the other side of the outer wall of the buffer tank.

[0006] Preferably, the outlet gas path structure includes a three-way pipe, one side of the three-way pipe is fixedly connected to the outlet gas path pipe, and a needle valve is symmetrically fixedly connected to one side of the three-way pipe. The other end of the needle valve is fixedly connected to a discharge pipe, and a flow meter is fixedly connected to the center of one side of the discharge pipe.

[0007] Preferably, the heating assembly includes an insulating shell, a bent pipe fixedly connected to the center of the lower surface of the insulating shell, the other end of the bent pipe fixedly connected to the side wall of the buffer tank, an outer pipe fixedly connected to the center of the upper surface of the insulating shell, internally threaded sleeves symmetrically fixedly connected to the upper surface of the insulating shell, and the inner wall of the internally threaded sleeves is threaded, an externally threaded sleeve is threadedly connected to the threaded part of the inner wall of the internally threaded sleeve, and a heating rod is fixedly connected to the center of the externally threaded sleeve.

[0008] Preferably, the pressure reducing valve is an R23 series medium flow stainless steel pressure reducing valve, the valve body and valve core of the pressure reducing valve are made of 316L stainless steel, the valve seat is made of PTFE or PCTFE, and the remaining parts are made of 304 stainless steel.

[0009] Preferably, the gas connection pipe is made of corrosion-resistant metal.

[0010] Preferably, a base is fixedly connected to the lower surface of the buffer tank, and a circular hole is provided on the surface of the base.

[0011] Compared with existing technologies, the beneficial effects of this utility model are as follows: This utility model, through the reasonable arrangement of heating components, heats and traces the buffer tank and pressure reducing valve separately, ensuring that the highest boiling point of n-octane in liquefied petroleum gas can be fully vaporized, while meeting the working temperature requirement of 100℃. Simultaneously, the use of a high-performance R23 series stainless steel pressure reducing valve achieves instantaneous and stable pressure reduction of the sample, ensuring that all components vaporize instantaneously and simultaneously, effectively improving sample injection repeatability. Testing shows that the sample injection repeatability is ≤4%, meeting the requirements of the NB / SH / T0230-2019 standard. The pressure reducing valve uses a 316L stainless steel valve body and valve core, and PTF... The E / PCTFE valve seat and other 304 stainless steel components possess excellent high-temperature, high-pressure, and corrosion resistance, capable of withstanding a liquid injection pressure of 1380 kPa at an operating temperature of 150℃, thus extending the equipment's service life. A flow control assembly consisting of a needle valve and a flow meter allows for precise control of the sample outlet flow rate, preventing instability from affecting test results. Simultaneously, a well-designed gas path connection reduces sample residue, further improving test accuracy. The position and length of the pressure gauge and pressure reducing valve can be customized to suit different laboratory installation environments and operational needs, enhancing the equipment's practicality and flexibility. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 for Figure 1 Detailed image of the heating element; Figure 3 for Figure 1 Detailed view of the threaded sleeve with internal and external threads; Figure 4 for Figure 1 Detailed diagram of the central exhaust air passage structure; Figure 5 This is a detailed diagram of the gas path of this utility model; In the diagram: 1. Buffer tank; 2. Gas connection pipe; 3. Pressure reducing valve; 4. Adjusting knob; 5. Pressure gauge; 6. Gas outlet pipe; 7. Gas outlet structure; 71. T-connector; 72. Needle valve; 73. Discharge pipe; 74. Flow meter; 8. Heating assembly; 81. Bend; 82. Insulation shell; 83. External pipe; 84. Internal threaded sleeve; 85. External threaded sleeve; 86. Heating rod; 9. Base. Detailed Implementation

[0013] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0014] Please see Figure 1-5 This utility model provides a laboratory flash evaporator for determining the composition of liquefied petroleum gas, including a buffer tank 1. A gas connection pipe 2 is fixedly connected to the center of the front side wall of the buffer tank 1. A pressure reducing valve 3 is connected to the other end of the gas connection pipe 2 via a flange. An adjustment knob 4 is connected to the other side of the pressure reducing valve 3 via a flange. An outlet gas pipe 6 is fixedly connected to one side of the outer wall of the buffer tank 1. An outlet gas structure 7 is fixedly connected to the other end of the outlet gas pipe 6. A heating component 8 is fixedly connected to the other side of the outer wall of the buffer tank 1.

[0015] The buffer tank 1 is made of 316L stainless steel with a volume of 200mL. The pressure reducing valve 3 is an R23 series stainless steel pressure reducing valve. It is first heated to the set temperature (100℃, 150℃) by the heating component 8 and kept at that temperature. The liquefied petroleum gas sample enters the buffer tank 1 at a pressure of 1380kPa, instantly reducing the sample pressure in the buffer tank 1 from 1380kPa (about 13.8MPa) to below 1MPa, so that all components of the sample are vaporized instantly and simultaneously. The flow rate control component is completed by the gas outlet structure 7, which accurately controls the outlet flow rate. The gas path connection is reasonable. The sample injection repeatability of this utility model is ≤4%. It can withstand a pressure of 1380kPa at 100℃, which meets the NB / SH / T0230-2019 standard. It is suitable for the determination of the composition of liquefied petroleum gas. The detection accuracy and equipment stability are high. The pressure gauge 5 is a stainless steel pressure gauge with a range of 0-20MPa, which is used to monitor the outlet pressure of the buffer tank in real time, which is convenient for operators to observe.

[0016] like Figure 1 and Figure 4 The exhaust gas path structure 7 shown includes a three-way pipe 71. One side of the three-way pipe 71 is fixedly connected to the exhaust gas path pipe 6. A needle valve 72 is symmetrically fixedly connected to the two-way side of the three-way pipe 71. The other end of the needle valve 72 is fixedly connected to a discharge pipe 73. A flow meter 74 is fixedly connected to the center of one side of the discharge pipe 73. The specific usage process of the exhaust gas path structure 7 is as follows: the flow rate control component is completed by the exhaust gas path structure 7. Through the cooperation of the main structure needle valve 72 and the flow meter 74, the outlet flow rate is accurately controlled. The gas path connection is reasonable. This utility model... The new type of sample injection repeatability is ≤4%, can withstand 1380kPa pressure at 100℃, conforms to NB / SH / T0230-2019 standard, is suitable for the determination of liquefied petroleum gas composition, and has high detection accuracy and equipment stability. The needle valve 72 is a J13W internal thread needle valve, and the flow meter 74 has a range of 0-60mL / min. The outlet of the needle valve 72 on one side is connected to the flow meter 74. By adjusting the opening of the needle valve 72, the sample outlet flow rate is controlled at 30mL / min. The flow meter 74 monitors the flow rate in real time and provides feedback.

[0017] like Figure 1 , Figure 2 , Figure 3 As shown, the heating assembly 8 includes an insulation shell 82. A bent pipe 81 is fixedly connected to the center of the lower surface of the insulation shell 82, and the other end of the bent pipe 81 is fixedly connected to the side wall of the buffer tank 1. An outer pipe 83 is fixedly connected to the center of the upper surface of the insulation shell 82. Internally threaded sleeves 84 are symmetrically fixedly connected to the upper surface of the insulation shell 82, and the inner wall of the internally threaded sleeves 84 is threaded. An externally threaded sleeve 85 is threadedly connected to the threaded part of the inner wall of the internally threaded sleeve 84. A heating rod 86 is fixedly connected to the center of the externally threaded sleeve 85. The specific usage process of the heating assembly 8 is as follows: The heating assembly 8 contains two heating rods 8... 6. The heating power is 800W, fixed at the center of the external threaded sleeve 85, and simultaneously threaded into the internal threaded sleeve 84 through the external threaded sleeve 85, which can be fixed to the top of the heat insulation shell 82. The heat insulation shell 82 is made of high temperature resistant heat insulation material and is set on the outside of the buffer tank 1. The internal heating rod 86 is used to heat the liquefied petroleum gas sample in the buffer tank 1 to 100℃ (higher than the boiling point of n-octane 125-127℃) to ensure that the sample is completely vaporized. Temperature control heating is achieved by platinum resistance and Omron meter. The heating temperature of the internal heating rod 86 is set to 150℃, which meets the standard requirements for working temperature.

[0018] like Figure 1 As shown, pressure reducing valve 3 is an R23 series medium flow stainless steel pressure reducing valve. The valve body and valve core of pressure reducing valve 3 are made of 316L stainless steel, the valve seat is made of PTFE or PCTFE, and the remaining parts are made of 304 stainless steel.

[0019] like Figure 1As shown, the gas connection pipe 2 is made of corrosion-resistant metal.

[0020] like Figure 1 As shown, a base 9 is fixedly connected to the lower surface of the buffer tank 1, and a round hole is provided on the surface of the base 9.

[0021] Working Principle: This device is used in the flash evaporation process. Through improvements in vaporization and pressure control, as well as temperature adaptability, the buffer tank 1 is made of 316L stainless steel with a volume of 200mL. The heating assembly 8 includes two heating rods 86 with a heating power of 800W, fixed at the center of the external threaded sleeve 85. Simultaneously, the external threaded sleeve 85 is threaded into the internal threaded sleeve 84, allowing it to be fixed to the top of the insulation shell 82. The insulation shell 82 is made of high-temperature resistant heat-insulating material and is located on the outside of the buffer tank 1. The internal heating rods 86 are used to heat the liquefied petroleum gas sample in the buffer tank 1 to 100℃ (125-127℃ higher than the boiling point of n-octane), ensuring complete vaporization of the sample. This is achieved through platinum resistance thermometers and Omron thermometers. The temperature control heating is achieved through a control panel. The internal heating rod 86 is set to a temperature of 150℃, meeting the standard operating temperature requirements. Its inlet is connected to the outlet of the gas connection pipe 2, controlling the liquefied petroleum gas sample to enter the buffer tank at a pressure of 1380 kPa. The pressure reducing valve 3 is an R23 series stainless steel pressure reducing valve, with the valve body and valve core made of 316L stainless steel and the valve seat made of PTFE. The maximum inlet pressure is selected as 3500 Psi, and the output pressure range is 0-290 Psi. The inlet and outlet ports are 3 / 4" NPT(F). The maximum inlet pressure of pressure reducing valve 3 is 500 Psi or 3500 Psi, the output pressure range is 0-290 Psi, the operating temperature range is -40 to 150℃, and the leakage rate is 1×10⁻⁻⁻⁶. 8With an atm·cc / secHe and a CV value of 1.6, the sample pressure in buffer tank 1 is instantly reduced from 1380 kPa (approximately 13.8 MPa) to below 1 MPa, achieving instantaneous and simultaneous vaporization of all sample components. The flow rate control component is implemented by the outlet gas path structure 7. Through the cooperation of the main structure needle valve 72 and flow meter 74, the outlet flow rate is precisely controlled. The gas path connection is reasonable. This utility model has a sample injection repeatability of ≤4%, can withstand 1380 kPa pressure at 100℃, conforms to NB / SH / T0230-2019 standard, and is suitable for the determination of liquefied petroleum gas composition. It has high detection accuracy and equipment stability. The needle valve 72 is a J13W internal thread needle valve, and the flow meter 74 has a range of 0-60 mL / min. The outlet of the needle valve 72 on one side is connected to the flow meter 74. By adjusting the opening of the needle valve 72, the sample outlet flow rate is controlled at 30 mL / min. The flow meter 74 monitors the flow rate in real time and provides feedback. The pressure gauge 5 is a stainless steel pressure gauge with a range of 0-20MPa, used to monitor the outlet pressure of the buffer tank in real time. The pressure gauge 5 is installed at a height of 30cm from the equipment base for easy observation by the operator. In this embodiment, the flash evaporator is first heated to the set temperature (100℃, 150℃) by the heating component 8 and kept at that temperature. The liquefied petroleum gas sample enters the buffer tank 1 at a pressure of 1380kPa. After vaporization, the sample enters the needle valve 72 and the flow meter 74, so that the flow rate displayed by the rotor flow meter is stabilized at 30mL / min. Subsequently, the sample enters the gas chromatograph through the GC interface for detection. After multiple tests, the sample injection repeatability of this flash evaporator is 3.2% (≤4%). It can stably withstand a pressure of 1380kPa at a working temperature of 100℃, which meets the requirements of the NB / SH / T0230-2019 standard.

[0022] 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. A laboratory flash evaporator for determining the composition of liquefied petroleum gas, characterized in that: The buffer tank (1) is fixedly connected to a gas connection pipe (2) at the center of the front side wall of the buffer tank (1). A pressure reducing valve (3) is connected to the flange at the other end of the gas connection pipe (2). An adjusting knob (4) is connected to the flange on the other side of the pressure reducing valve (3). An outlet gas pipe (6) is fixedly connected to one side of the outer wall of the buffer tank (1). An outlet gas structure (7) is fixedly connected to the other end of the outlet gas pipe (6). A heating component (8) is fixedly connected to the other side of the outer wall of the buffer tank (1).

2. The laboratory flash evaporator for determining the composition of liquefied petroleum gas according to claim 1, characterized in that: The outlet air passage structure (7) includes a three-way pipe (71). One side of the three-way pipe (71) is fixedly connected to the outlet air passage pipe (6). A needle valve (72) is symmetrically fixedly connected to one side of the three-way pipe (71). The other end of the needle valve (72) is fixedly connected to a discharge pipe (73). A flow meter (74) is fixedly connected to the center of one side of the discharge pipe (73).

3. The laboratory flash evaporator for determining the composition of liquefied petroleum gas according to claim 1, characterized in that: The heating assembly (8) includes an insulation shell (82), a bent pipe (81) is fixedly connected to the center of the lower surface of the insulation shell (82), the other end of the bent pipe (81) is fixedly connected to the side wall of the buffer tank (1), an outer pipe (83) is fixedly connected to the center of the upper surface of the insulation shell (82), an internal threaded sleeve (84) is symmetrically fixedly connected to the upper surface of the insulation shell (82), and the inner wall of the internal threaded sleeve (84) is threaded. An external threaded sleeve (85) is threadedly connected to the inner threaded part of the internal threaded sleeve (84), and a heating rod (86) is fixedly connected to the center of the external threaded sleeve (85).

4. A laboratory flash evaporator for determining the composition of liquefied petroleum gas according to claim 1, characterized in that: The pressure reducing valve (3) is an R23 series medium flow stainless steel pressure reducing valve. The valve body and valve core of the pressure reducing valve (3) are made of 316L stainless steel, the valve seat is made of PTFE or PCTFE, and the other parts are made of 304 stainless steel.

5. A laboratory flash evaporator for determining the composition of liquefied petroleum gas according to claim 1, characterized in that: The gas connection pipe (2) is made of corrosion-resistant metal.

6. A laboratory flash evaporator for determining the composition of liquefied petroleum gas according to claim 1, characterized in that: The lower surface of the buffer tank (1) is fixedly connected to a base (9), and the surface of the base (9) is provided with a round hole.

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