Liquid carbon dioxide detection moisture and oxygen content pretreatment device

Abstract

The utility model relates to food -grade liquid carbon dioxide detection technical field, concretely is a kind of liquid carbon dioxide detection moisture and oxygen content pretreatment device, including the steel bottle of liquid carbon dioxide, first pressure reducing valve is equipped at the steel bottle export, first pressure reducing valve is connected with heating assembly inlet end by first gas pipe, heating assembly outlet end is connected with second pressure reducing valve, second pressure reducing valve is connected with detection component by second gas pipe, and rotor flowmeter is equipped on second gas pipe.The utility model passes through first pressure reducing valve and slowly transports low-temperature liquid carbon dioxide to first gas pipe, makes low-temperature liquid carbon dioxide change into unstable low-temperature gaseous carbon dioxide, unstable low-temperature gaseous carbon dioxide is changed into stable gaseous carbon dioxide by heating component, and gaseous carbon dioxide of steady voltage, steady flow is sent to detection equipment by second pressure reducing valve and rotor flowmeter, reduces the time required for detection, ensures the accuracy and reliability of detection result, avoids damaging detection equipment.

Description

Technical Field

[0001] This utility model relates to the field of food-grade liquid carbon dioxide detection technology, specifically a pretreatment device for detecting moisture and oxygen content in liquid carbon dioxide. Background Technology

[0002] According to the "Hygienic Standard for the Use of Food Additives" (GB2760-2014), liquid carbon dioxide can be used as a food additive in soft drinks, gasoline, and beverages. In addition, liquid carbon dioxide has a variety of applications in the food industry, including adjusting the acidity and taste of beverages, as an ingredient in popping candy, making rice wine more refreshing and delicious, and helping dough to expand and become soft in the making of pastries.

[0003] To ensure the quality and safety of food-grade carbon dioxide, the National Food Safety Standard for Food Additives (GB 1886.228-2016) specifies the moisture and oxygen content indicators for carbon dioxide. Since current testing equipment lacks the function of liquid-to-gas conversion, this standard also specifies a method for testing liquid carbon dioxide. Specifically, when testing the moisture and oxygen content in liquid carbon dioxide, it must first be vaporized. If liquid carbon dioxide is directly connected to the testing equipment, the flow rate will fluctuate greatly during the testing process, failing to stabilize within the equipment's specified limits. This significantly prolongs the testing time and affects the accuracy and reliability of the results. Furthermore, the extremely low temperature of liquid carbon dioxide poses a significant risk of damaging the internal sensors of the testing equipment, rendering it unable to perform its testing function properly. Utility Model Content

[0004] The purpose of this invention is to provide a pretreatment device for detecting moisture and oxygen content in liquid carbon dioxide, addressing the shortcomings of existing technologies. This device pre-treats liquid carbon dioxide before detection, converting it into stable-pressure, stable-flow gaseous carbon dioxide before delivering it to the detection equipment, thus solving the problems in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A pretreatment device for detecting moisture and oxygen content in liquid carbon dioxide includes a steel cylinder containing liquid carbon dioxide. A first pressure reducing valve is provided at the outlet of the steel cylinder. The first pressure reducing valve is connected to the inlet end of a heating component through a first gas pipe. The outlet end of the heating component is connected to a second pressure reducing valve. The second pressure reducing valve is connected to a detection component through a second gas pipe. A rotor flow meter is provided on the second gas pipe.

[0007] Furthermore, an auxiliary pressure reducing valve is provided on the first trachea.

[0008] Furthermore, the heating assembly includes a heating box and a through-plate connector that runs through both ends of the heating box. One end of the through-plate connector is connected to a first air pipe, and the other end is connected to a second air pipe. An electric heating tape is installed inside the heating box.

[0009] Furthermore, the electric tracing cable is spirally wound around the plate connector inside the heating box.

[0010] Furthermore, the detection assembly includes a dew point meter for detecting moisture content and a trace oxygen analyzer for detecting oxygen content. One end of the second gas tube is connected to the heating assembly, and the other end is connected to the inlet end of a three-way valve. One outlet end of the three-way valve is connected to the dew point meter, and the other outlet end is connected to the trace oxygen analyzer.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] This invention controls the slow delivery of cryogenic liquid carbon dioxide from a gas cylinder to a first gas pipe at low pressure and low flow rate via a first pressure-reducing valve. This allows the cryogenic liquid carbon dioxide to transform into unstable cryogenic gaseous carbon dioxide at atmospheric pressure, or to purge the delivery pipeline at high pressure and high flow rate. An electric heating tape heats the unstable cryogenic gaseous carbon dioxide flowing into the through-plate joint, transforming it into a stable gaseous carbon dioxide. A second pressure-reducing valve reduces the heated and pressurized gaseous carbon dioxide to atmospheric pressure, and a rotor flow meter controls the flow rate to the testing equipment to meet the specified limits of the testing equipment. In other words, a stable pressure and flow rate of gaseous carbon dioxide is delivered to the testing equipment via the second pressure-reducing valve and the rotor flow meter. Pre-treatment of the cryogenic liquid carbon dioxide by the pre-treatment device reduces testing time, improves testing efficiency, ensures the accuracy and reliability of the test results, avoids damage to the testing equipment, and meets the testing requirements of the National Food Safety Standard for Food Additives Carbon Dioxide (GB 1886.228-2016). Attached Figure Description

[0013] Figure 1 A schematic diagram of the overall structure of a liquid carbon dioxide pretreatment device for detecting moisture and oxygen content provided by this utility model.

[0014] The attached figures are labeled as follows:

[0015] 1. Gas cylinder; 2. First pressure reducing valve; 3. First gas pipe; 4. Heating assembly; 41. Heating box; 42. Through-plate connector; 43. Electric heating tape; 44. Power supply; 5. Second pressure reducing valve; 6. Second gas pipe; 7. Rotor flow meter; 8. Detection assembly; 81. Dew point meter; 82. Trace oxygen analyzer; 83. Three-way valve; 9. Auxiliary pressure reducing valve. Detailed Implementation

[0016] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0017] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0018] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0020] For easier understanding, please refer to Figure 1This embodiment provides a pretreatment device for detecting moisture and oxygen content in liquid carbon dioxide. It includes a 2L steel cylinder 1 storing liquid carbon dioxide. The outlet of the cylinder 1 is connected to the inlet of a first pressure-reducing valve 2. The outlet of the first pressure-reducing valve 2 is connected to one end of a first gas pipe 3. The first pressure-reducing valve 2 controls the flow of liquid carbon dioxide from the cylinder 1 to the first gas pipe 3 at low pressure and low flow rate or at high pressure and high flow rate. The other end of the first gas pipe 3 is connected to the inlet of a heating assembly 4. The heating assembly 4 heats the carbon dioxide flowing through it, stabilizing it (controllable flow rate). The outlet of the heating assembly 4 is connected to a second pressure-reducing valve 5. The second pressure-reducing valve 5 reduces the pressure of the heated carbon dioxide, adjusting it to atmospheric pressure. The second pressure-reducing valve 5 is connected to a detection assembly 8 via a second gas pipe 6. The detection assembly 8 detects the moisture and oxygen content in the carbon dioxide. A rotor flow meter 7 is connected in series on the second gas pipe 6, controlling the flow rate of carbon dioxide output to the detection assembly 8 to a preset value.

[0021] The heating assembly 4 includes a heating box 41, with a through-plate connector 42 passing through both ends of the heating box 41. One end of the through-plate connector 42 is connected to the first gas pipe 3, and the other end is connected to the second pressure reducing valve 5. An electric heating tape 43 is installed inside the heating box 41, spirally and evenly wound around the through-plate connector 42 in the middle of the heating box 41. The power supply 44 for controlling the heating of the electric heating tape 43 is located outside the heating box 41. Heating is achieved by energizing the electric heating tape 43, which transfers heat to the through-plate connector 42 inside the heating box 41, causing the through-plate connector 42 to heat up. When carbon dioxide is delivered from the first gas pipe 3 to the through-plate connector 42, the through-plate connector 42 transfers heat to the carbon dioxide, causing it to heat up, and then delivers the heated carbon dioxide to the second pressure reducing valve 5. The detection component 8 includes a dew point meter 81 for detecting moisture content and a trace oxygen analyzer 82 for detecting oxygen content. One end of the second gas tube 6 is connected to the second pressure reducing valve 5, and the other end of the second gas tube 6 is connected to the inlet end of a three-way valve 83. One outlet end of the three-way valve 83 is connected to the dew point meter 81, and the other outlet end is connected to the trace oxygen analyzer 82. The user can control the direction of carbon dioxide delivery according to actual detection needs. Furthermore, the gas tubes, components, and instruments can be connected in series via compression fittings. Preferably, the dew point meter 81 is the HDP-100 online precision dew point meter from Dalian Guangming Chemical Industry Gas Quality Monitoring Center Co., Ltd., and the trace oxygen analyzer 82 is the ERUN-QZ9100 online trace oxygen content analyzer from Xi'an Yingrun Environmental Protection Technology Group Co., Ltd.

[0022] After connecting the pipeline to all components and instruments, the user needs to purge the entire delivery pipeline, including the instruments, to ensure the accuracy and effectiveness of the test. Liquid carbon dioxide from cylinder 1 is delivered to the first gas pipe 3 at high pressure and high flow rate via the first pressure reducing valve 2. The carbon dioxide then flows sequentially through the through-plate connector 42, the second pressure reducing valve 5 (also at high pressure), the rotor flowmeter 7, the three-way valve 83, and the dew point meter 81 (or trace oxygen analyzer 82), expelling air from the entire delivery pipeline and completing the pre-test purging process. Furthermore, an auxiliary pressure reducing valve 9 is installed in series on the first gas pipe 3. Since the liquid carbon dioxide in cylinder 1 is at a low temperature (approximately -37°C), excessive output pressure during the purging process may cause the first pressure reducing valve 2 to freeze, potentially damaging it. In this case, the auxiliary pressure reducing valve 9 controls the output pressure and flow rate of the carbon dioxide to prevent damage to the testing component 8 due to excessive pressure. After the purging action is completed, the first pressure reducing valve 2 is closed to stop the delivery of carbon dioxide into the first gas pipe 3. Then, the electric heating tape 43 is powered on and preheated, and the dew point meter 81 (or trace oxygen analyzer 82) is turned on and ready. During the process of the electric heating tape 43 being heated to the preset temperature, the liquid carbon dioxide that is purging the delivery pipeline has also vaporized into gaseous carbon dioxide under atmospheric pressure.

[0023] After the heating cable 43 heats to the preset temperature, the liquid carbon dioxide in cylinder 1 is controlled by the first pressure reducing valve 2 to be delivered to the first gas pipe 3 at a low pressure and low flow rate (30 kPa). The liquid carbon dioxide slowly entering the first gas pipe 3 will rapidly vaporize under atmospheric pressure, becoming gaseous carbon dioxide in a low-temperature unstable state (large flow fluctuations and uncontrollable flow). The low-temperature unstable gaseous carbon dioxide will automatically enter the through-plate connector 42 along the first gas pipe 3 for heating. After being heated, the gaseous carbon dioxide becomes stable (flow rate controllable), that is, stable gaseous carbon dioxide is delivered to the second pressure reducing valve 5 through the heating component 4. However, the pressure of the gaseous carbon dioxide will also increase after being heated. After being heated and pressurized, the gaseous carbon dioxide will automatically enter the second pressure reducing valve 5 through the through-plate connector 42 for a second pressure reducing action. The second pressure reducing valve 5 controls the gaseous carbon dioxide in the through-plate connector 42 to be delivered to the rotor flow meter 7 at a pressure of 20 kPa. Then, the rotor flow meter 7 controls the flow rate of gaseous carbon dioxide output to the dew point meter 81 (or trace oxygen analyzer 82) to be 1 L / min. That is, through the second pressure reducing valve 5 and the rotor flow meter 7, stable pressure and stable flow gaseous carbon dioxide is delivered to the dew point meter 81 (or trace oxygen analyzer 82), thus completing the whole process of converting low temperature liquid carbon dioxide into stable pressure and stable flow gaseous carbon dioxide and delivering it to the dew point meter 81 (or trace oxygen analyzer 82).

[0024] Although the present invention has been described using the above preferred embodiments, it is not intended to limit the scope of protection of the present invention. Any changes and modifications made by those skilled in the art to the above embodiments without departing from the spirit and scope of the present invention shall still fall within the scope of protection of the present invention.

Claims

1. A pretreatment device for detecting moisture and oxygen content in liquid carbon dioxide, characterized in that, It includes a steel cylinder (1) containing liquid carbon dioxide, a first pressure reducing valve (2) is provided at the outlet of the steel cylinder (1), the first pressure reducing valve (2) is connected to the inlet end of the heating component (4) through a first gas pipe (3), the outlet end of the heating component (4) is connected to a second pressure reducing valve (5), the second pressure reducing valve (5) is connected to a detection component (8) through a second gas pipe (6), and a rotor flow meter (7) is provided on the second gas pipe (6).

2. The liquid carbon dioxide detection and moisture and oxygen content pretreatment device according to claim 1, characterized in that, An auxiliary pressure reducing valve (9) is provided on the first air pipe (3).

3. The liquid carbon dioxide detection and moisture and oxygen content pretreatment device according to claim 1, characterized in that, The heating assembly (4) includes a heating box (41) and a through-plate connector (42) that passes through both ends of the heating box (41). One end of the through-plate connector (42) is connected to the first air pipe (3), and the other end is connected to the second air pipe (6). An electric heating tape (43) is provided inside the heating box (41).

4. The liquid carbon dioxide detection and moisture and oxygen content pretreatment device according to claim 3, characterized in that, The electric heating cable (43) is spirally wound around the plate connector (42) inside the heating box (41).

5. The liquid carbon dioxide detection and moisture and oxygen content pretreatment device according to claim 1, characterized in that, The detection component (8) includes a dew point meter (81) for detecting moisture content and a trace oxygen analyzer (82) for detecting oxygen content. One end of the second air tube (6) is connected to the heating component (4), and the other end is connected to the inlet end of the three-way valve (83). One outlet end of the three-way valve (83) is connected to the dew point meter (81), and the other outlet end is connected to the trace oxygen analyzer (82).

Images