High-precision water vapor gasification device with stable gas supply for test

Abstract

The invention belongs to the technical field of steam generators, and particularly discloses a high-precision steam gasification device with stable gas supply for a test. A liquid inlet of a medium-pressure constant-flow pump of the device is connected with a water storage tank, an evaporation tank is obliquely arranged, a carrier gas inlet and a steam release port are formed in the upper end and the lower end of the evaporation tank respectively, a distributor is suspended in the evaporation tank, and one end of the distributor is fixed to a water injection port in the side of the evaporation tank; two ends of the carrier gas preheating pipe are respectively connected with the carrier gas inlet and the carrier gas supply device; the heat tracing band is fixed on the outer walls of the evaporation tank and the carrier gas preheating pipe; the carrier gas flow meter and the carrier gas control valve are respectively arranged on a pipeline for connecting the carrier gas preheating pipe and the carrier gas supply device, the water injection control valve is arranged on a pipeline for connecting a water injection port of the evaporation tank, and the controller is electrically connected with the carrier gas flow meter, the carrier gas control valve, the water injection control valve, the medium-pressure constant flow pump and the heat tracing band. The device has the advantages of being simple in structure, low in cost, high in evaporation efficiency and stable, controllable and accurate in water vapor flow.

Description

Technical Field

[0001] This invention belongs to the field of steam generator technology, specifically relating to a high-precision steam vaporization device for testing that is simple in structure, low in cost, has high evaporation efficiency, and provides stable and controllable steam flow with a stable and precise gas supply. Background Technology

[0002] Real-world environments, such as industrial flue gas and vehicle exhaust, contain water vapor, which accelerates catalyst deactivation and thus affects catalytic activity. Therefore, in catalyst activity evaluation, water vapor needs to be introduced to simulate the actual atmosphere of industrial flue gas and vehicle exhaust in the syngas evaluation device, thereby simulating a realistic scenario and improving the accuracy of the evaluation results. In the catalytic activity evaluation system, the water vaporization device is a key component for simulating a humid reaction environment and precisely controlling the water content of the reaction system; its role extends to multiple stages, including condition control, mechanism research, and performance evaluation of the catalytic reaction. Therefore, providing a stable and precise water vapor flow rate during simulated gas mixing is a crucial consideration in the design of the water vaporization device in the catalytic activity evaluation system.

[0003] In traditional technology, steam is generated by heating a liquid to make it flow and boil. Although the structure is simple and the cost is low, it is difficult to obtain a stable and accurate steam flow rate because it is greatly affected by temperature, pressure and flow rate.

[0004] In existing technologies, high-precision water vaporization devices are typically based on a heating furnace and an evaporator. The evaporator is heated by a heating furnace with intelligent temperature control, and then liquid water is dripped into the high-temperature evaporator through a capillary tube, where it comes into contact with the heat storage evaporator and evaporates rapidly. The resulting water vapor is then mixed with the carrier gas and discharged. Although the evaporation rate is fast and the mixing effect is good, and the temperature can be precisely controlled by an intelligent temperature control system to ensure the stability of the vaporization process, the cost is relatively high due to the high requirements for heating elements and high-temperature resistant materials. Moreover, during long-term operation, problems such as scaling on the surface of the heat storage evaporator may occur, which will affect the evaporation efficiency and the life of the device. To address this, there is a carrier gas bubbling / saturation method, which involves introducing dry carrier gas into constant-temperature liquid water, causing the carrier gas to be saturated with water vapor as it passes through the water layer, forming a moist gas at a specific temperature. This method is simple in structure, low in cost, and has good stability. However, due to its reliance on the accuracy of temperature control and saturation efficiency, the accuracy of steam supply is limited. Furthermore, changing the water vapor concentration requires changing the saturator temperature, resulting in high thermal inertia and long response time. Moreover, changes in system pressure affect the saturated vapor pressure and the actual output concentration, and changing the water vapor flow rate will simultaneously change the water vapor concentration, making independent adjustment difficult. Therefore, it is mostly used for routine evaluations where accuracy requirements are not high, the water vapor concentration is relatively fixed, the flow rate range is moderate, and the budget is limited. In addition, there is a combined direct injection and flash vaporization technology that uses a high-precision liquid phase pump (such as an HPLC pump or injection pump) to continuously inject a small amount of deionized water into a high-temperature vaporization chamber for instantaneous vaporization, and then mixes it with other raw material gases before entering the reactor. Although this technology is convenient to operate and allows for rapid changes in water vapor flow rate by controlling the water supply through a metering pump, it is complex and costly due to the need for a precision liquid phase pump, a high-temperature and high-pressure vaporization chamber, and a precise temperature control system. Furthermore, excessively high injection rates, insufficient vaporization chamber temperatures, inadequate mixing, or excessively low carrier gas flow rates can all lead to incomplete vaporization of droplets, affecting the evaluation results. Another approach involves using microchannel heat exchangers to achieve efficient, continuous, and stable vaporization of liquid flowing through microchannels through boiling vaporization. While this technology offers high vaporization efficiency, low energy consumption, good temperature uniformity, and supports multi-component gas mixing, the boiling process within the microchannels is a complex multiphase flow process. The growth, expansion, and movement of bubbles are easily affected by various factors, leading to poor flow stability and large pressure drops. Moreover, the microchannels are prone to clogging, resulting in high maintenance costs.

[0005] Therefore, developing a high-precision steam vaporization device with simple structure, low cost, high evaporation efficiency, and stable and controllable steam flow rate is of great significance for improving the accuracy of evaluation results of syngas evaluation devices. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a high-precision steam vaporization device for testing that features a simple structure, low cost, high evaporation efficiency, and stable and controllable steam flow rate.

[0007] The high-precision steam vaporization device for stable gas supply in this invention is implemented as follows: it includes a liquid delivery unit, a vaporization unit, and a control unit. The liquid delivery unit includes a water storage tank and a medium-pressure constant flow pump. The inlet of the medium-pressure constant flow pump is connected to the outlet of the water storage tank through a pipeline. The vaporization unit includes an evaporator, a distributor, a carrier gas preheating pipe, and a heating tape. The evaporator is an inclined cylindrical sealed tank with a carrier gas inlet at the top and a steam release port at the bottom. The distributor is made of water-absorbing material and is suspended inside the evaporator, with one end fixedly connected to a water inlet on the side of the evaporator. The water inlet of the evaporator is connected to the outlet of a medium-pressure constant flow pump through a pipe. The carrier gas preheating pipe is connected to the carrier gas inlet at the top of the evaporator. The end of the carrier gas preheating pipe away from the carrier gas inlet of the evaporator is connected to a carrier gas supply device through a pipe. The heating tape is fixedly installed on the outer walls of the evaporator and the carrier gas preheating pipe, respectively. The control unit includes a carrier gas flow meter, a carrier gas control valve, a water injection control valve, and a controller. The carrier gas flow meter and the carrier gas control valve are respectively installed on the pipeline connecting the carrier gas preheating pipe and the carrier gas supply device. The water injection control valve is installed on the pipeline connecting the water inlet of the evaporator and the medium-pressure constant flow pump. The controller is electrically connected to the carrier gas flow meter, the carrier gas control valve, the water injection control valve, the medium-pressure constant flow pump, and the heating tape.

[0008] Furthermore, the evaporator is a columnar sealed tank with its central axis inclined at 30 to 60 degrees to the ground. The water inlet of the evaporator is located in the upper middle part of the side wall of the evaporator. One end of the distributor is fixedly connected to the water inlet of the evaporator and the other end hangs inside the evaporator.

[0009] Furthermore, the distributor is a glass fiber belt, rock wool fiber belt, or ceramic fiber belt. One end of the distributor is twisted into a linear structure and fitted with a compression fitting. The distributor is sealed and embedded in the water inlet of the evaporator through the compression fitting. The other end of the distributor, away from the compression fitting, hangs naturally in the evaporator along the plumb line.

[0010] Furthermore, the distributor is twisted into a linear structure, with one end extending 10-20 mm into the water inlet of the evaporator. The side of the distributor away from the water inlet of the evaporator hangs down naturally in the direction of a plumb bob, and the bottom end does not contact the inner wall of the evaporator.

[0011] Furthermore, the outlet pipe of the water storage tank is connected to a filter head or is equipped with a filter screen, and the liquid flow rate at the outlet of the medium-pressure constant flow pump does not exceed 10.00 ml / min.

[0012] Furthermore, the heat tracing cable includes a first heat tracing cable and a second heat tracing cable. The first heat tracing cable is fixedly installed on the outer wall of the evaporator and has a first thermocouple built into it. The second heat tracing cable is fixedly installed on the outer wall of the carrier gas preheating pipe and has a second thermocouple built into it. The first thermocouple and the second thermocouple are electrically connected to the controller.

[0013] Furthermore, the heating temperature of the first and second heat tracing cables shall not exceed 300°C and shall not be lower than 180°C, and the control setting temperature of the first and second heat tracing cables shall be consistent.

[0014] Furthermore, the outer wall of the evaporator is wrapped with a first insulation tape, and the first heat tracing tape is wrapped inside the first insulation tape; the outer wall of the carrier gas preheating pipe is wrapped with a second insulation tape, and the second heat tracing tape is wrapped inside the second insulation tape; the pipe connected to the steam release port at the bottom of the evaporator is wrapped with a third insulation tape.

[0015] Furthermore, the water supply flow rate of the medium-pressure constant flow pump V 液态水 for: ,

[0016] In the formula: V 液态水 The unit is mL / min; V 总流量 The total flow rate of the atmosphere output from the vapor release port of the evaporator, in mL / min; C 水蒸气 The design concentration of water vapor in the output atmosphere from the vapor release port of the evaporator, in %; ρ 水 The density of water, in g / cm³ 3 .

[0017] The present invention has the following beneficial effects: 1. Compared to traditional high-precision evaporators (requiring heating furnaces and high-temperature resistant materials) and direct injection flash vaporization systems (requiring precision liquid phase pumps and high-temperature, high-pressure vaporization chambers), the high-precision steam vaporization device of this invention utilizes a medium-pressure constant flow pump, an evaporator, a water-absorbing distributor, conventional heating elements, and control components. The core components are technologically mature and readily available, significantly reducing costs. In particular, the vaporization unit innovatively employs an inclined evaporator combined with a distributor made of water-absorbing material, eliminating the need for high-precision liquid phase pumps, complex microchannel heat exchangers, and expensive high-temperature, high-pressure evaporation chambers. This effectively simplifies the structure, thereby significantly reducing manufacturing and maintenance costs and solving the problem of high costs associated with traditional high-precision devices.

[0018] 2. The high-precision water vaporization device of the present invention features an inclined evaporator tank, coupled with a water-absorbing distributor with an ultra-large specific surface area. This allows the liquid to be uniformly introduced into the evaporator tank and diffused on its own surface, thereby effectively increasing the contact area between the liquid and the carrier gas to improve evaporation efficiency. Simultaneously, the heating cable heats the evaporator tank and the carrier gas preheating pipe. After the preheated carrier gas enters the evaporator tank, it can fully contact the liquid on the surface of the distributor to accelerate the vaporization of the liquid, thereby ensuring rapid and complete evaporation of the liquid. This not only further improves the evaporation efficiency but also avoids the situation where incomplete vaporization of droplets affects the evaluation results.

[0019] 3. The high-precision water vaporization device of this invention features a medium-pressure constant flow pump in its liquid delivery unit that can precisely control the water supply flow rate. Combined with the controller in the control unit's coordinated regulation of the carrier gas flow meter, carrier gas control valve, and water injection control valve, it can accurately calculate and adjust the water supply flow rate of the medium-pressure constant flow pump according to the set water vapor concentration of the output atmosphere and the input carrier gas flow rate using a specific formula. This achieves independent adjustment and dynamic matching of water vapor concentration and carrier gas flow rate, overcoming the limitations of concentration / flow coupling in traditional bubbling methods. Simultaneously, the control unit, through the controller in conjunction with the carrier gas flow meter, carrier gas and water injection control valves, medium-pressure constant flow pump, and heating tape, can adjust the carrier gas flow rate, liquid water input, and evaporation temperature in real time to form a closed-loop control, solving the accuracy problems caused by temperature fluctuations or saturation efficiency in traditional carrier gas bubbling methods. Moreover, the distributor's uniform liquid distribution and buffering effect enable the liquid to vaporize instantly without boiling or explosive boiling, and eliminate the weak pulses from the medium-pressure constant flow pump, thus stabilizing the vaporization process. Combined with stable heating temperature control, it can avoid droplet splashing, local scaling, and temperature fluctuations, further ensuring the stability of the steam vaporization process and keeping the output steam flow rate stable. This solves the problem of unstable flow rate caused by temperature, pressure, and flow rate in traditional technologies.

[0020] 4. The high-precision steam vaporization device of the present invention features an inclined evaporator, which reduces the dead zone in the multiphase flow, facilitating the smooth mixing of vaporized steam and carrier gas and its exit from the bottom steam release port, thus reducing the risk of liquid accumulation and scaling inside the tank. Furthermore, the distributor is suspended inside the evaporator and does not contact the inner wall, avoiding incomplete vaporization of droplets, localized overheating, and scaling problems caused by contact, extending the device's service life and improving operational stability. Simultaneously, the high-precision steam vaporization device of the present invention, due to its high gas supply accuracy, can meet the requirements of catalytic activity evaluation scenarios with high steam flow control requirements. Its low cost and simple structure also make it suitable for various conventional evaluation scenarios with limited budgets and requiring flexible adjustment of steam concentration and flow rate, effectively solving the problem of limited applicability of existing technical solutions. In summary, the high-precision water vaporization device of this invention innovatively adopts a physical structure design of fiber capillary distributor + tilted evaporator, combined with mathematical model-based flow closed-loop control, to achieve precise control of the water vapor environment in the syngas evaluation device. This effectively solves the problems of large flow fluctuations, high costs, and difficult adjustment in existing technologies. It can provide a stable, high-precision, and low-cost water vapor simulation environment for catalytic activity evaluation, significantly improving the accuracy of catalyst testing under humid atmospheres such as industrial flue gas / vehicle exhaust, thereby promoting the research and development efficiency of environmentally friendly catalytic materials. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structural principle of a high-precision steam vaporization device for testing purposes to ensure stable gas supply. Figure 2 This is a cross-sectional view of the evaporator and its connection structure according to the present invention; In the diagram, 1-liquid delivery unit, 11-water storage tank, 12-medium pressure constant flow pump, 2-vaporization unit, 21-evaporator, 22-distributor, 23-carrier gas preheating pipe, 24-first heating tape, 25-second heating tape, 26-first insulation belt, 27-second insulation belt, 28-third insulation belt, 3-control unit, 31-carrier gas flow meter, 32-carrier gas control valve, 33-water injection control valve; Figure 3 The diagram shows a comparison of the water vapor concentration response rate and stability of the gasification device of the present invention, the conventional technology, and the imported gasification device in the embodiments. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this does not limit the present invention in any way. Any changes or improvements made based on the teachings of the present invention shall fall within the protection scope of the present invention.

[0023] like Figure 1 and 2 As shown, the high-precision steam vaporization device for stable gas supply of the present invention includes a liquid conveying unit 1, a vaporization unit 2, and a control unit 3. The liquid delivery unit 1 includes a water storage tank 11 and a medium-pressure constant flow pump 12. The inlet of the medium-pressure constant flow pump 12 is connected to the outlet of the water storage tank 11 through a pipeline. The vaporization unit 2 includes an evaporator 21, a distributor 22, a carrier gas preheating pipe 23, and a heat tracing cable. The evaporator 21 is an inclined cylindrical sealed tank with a carrier gas inlet at the top and a steam release port at the bottom. The distributor 22 is made of water-absorbing material and is suspended inside the evaporator 21, with one end fixedly connected to the water inlet on the side of the evaporator 21. The water inlet of the evaporator 21 is connected to the liquid outlet of the medium-pressure constant flow pump 12 through a pipe. The carrier gas preheating pipe 23 is connected to the carrier gas inlet at the top of the evaporator 21. The end of the carrier gas preheating pipe 23 away from the carrier gas inlet of the evaporator 21 is connected to the carrier gas supply device through a pipe. The heat tracing cable is fixedly installed on the outer walls of the evaporator 21 and the carrier gas preheating pipe 23, respectively. The control unit 3 includes a carrier gas flow meter 31, a carrier gas control valve 32, a water injection control valve 33, and a controller. The carrier gas flow meter 31 and the carrier gas control valve 32 are respectively installed on the pipeline connecting the carrier gas preheating pipe 23 and the carrier gas supply device. The water injection control valve 33 is installed on the pipeline connecting the water inlet of the evaporator 21 and the medium-pressure constant flow pump 12. The controller is electrically connected to the carrier gas flow meter 31, the carrier gas control valve 32, the water injection control valve 33, the medium-pressure constant flow pump 12, and the heating tape.

[0024] The medium-pressure constant flow pump 12 is connected to the controller via signal. By receiving instructions from the controller, it can control the opening and closing of the carrier gas control valve 32, the water injection control valve 33, the medium-pressure constant flow pump 12, and the liquid water flow rate, thereby enabling remote control and real-time monitoring.

[0025] The evaporator 21 is a columnar sealed tank with its central axis inclined at 30 to 60 degrees to the ground. The water inlet of the evaporator 21 is located in the upper middle part of the side wall of the evaporator 21. One end of the distributor 22 is fixedly connected to the water inlet of the evaporator 21 and the other end is suspended inside the evaporator 21.

[0026] The distributor 22 is a glass fiber belt, rock wool fiber belt or ceramic fiber belt. One end of the distributor 22 is twisted into a linear structure and fitted with a compression fitting. The distributor 22 is sealed and embedded in the water inlet of the evaporator 21 through the compression fitting. The other end of the distributor 22 away from the compression fitting hangs naturally in the evaporator 21 along the plumb line.

[0027] The distributor 22 is twisted into a linear structure, with one end extending 10-20 mm into the water inlet of the evaporator 21. The side of the distributor 22 away from the water inlet of the evaporator 21 hangs down naturally in the direction of a plumb bob, and the bottom end does not contact the inner wall of the evaporator 21.

[0028] The outlet pipe of the water storage tank 11 is connected to a filter head or is equipped with a filter screen, and the liquid flow rate at the outlet of the medium-pressure constant flow pump 12 does not exceed 10.00 ml / min.

[0029] The heat tracing cable includes a first heat tracing cable 24 and a second heat tracing cable 25. The first heat tracing cable 24 is fixedly installed on the outer wall of the evaporator 21 and has a first thermocouple built in it. The second heat tracing cable 25 is fixedly installed on the outer wall of the carrier gas preheating pipe 23 and has a second thermocouple built in it. The first thermocouple and the second thermocouple are electrically connected to the controller.

[0030] The heating temperature of the first heat tracing cable 24 and the second heat tracing cable 25 shall not exceed 300°C and shall not be lower than 180°C, and the control setting temperature of the first heat tracing cable 24 and the second heat tracing cable 25 shall be consistent.

[0031] The outer wall of the evaporator 21 is wrapped with a first insulation tape 26, and the first heat tracing tape 24 is wrapped inside the first insulation tape 26; the outer wall of the carrier gas preheating pipe 23 is wrapped with a second insulation tape 27, and the second heat tracing tape 25 is wrapped inside the second insulation tape 27; the pipe connected to the steam release port at the bottom of the evaporator 21 is wrapped with a third insulation tape 28.

[0032] The water supply flow rate of the medium-pressure constant flow pump 12 V 液态水 for: ,

[0033] In the formula: V 液态水 The unit is mL / min; V 总流量 The total flow rate of the atmosphere output from the vapor release port of evaporator 21, in mL / min; C 水蒸气 The design concentration of water vapor in the output atmosphere from the steam release port of evaporator 21, in %; ρ 水 This is the density of water, expressed in g / cm³. 3 .

[0034] The carrier gas is any one or any combination of nitrogen, helium, and argon.

[0035] The controller is a PLC, industrial computer, or server.

[0036] Example

[0037] like Figure 1 and 2As shown in the embodiment, a cylindrical stainless steel tank with a diameter of 57 mm and a height of 200 mm is used as the evaporator 21, and the central axis of the evaporator 21 is at a 45° angle to the ground. Simultaneously, a glass fiber strip (i.e., distributor 22) with a length of 80 mm, a width of 30 mm, and a thickness of 2 mm is used. One end of the glass fiber strip is twisted into a linear structure with a length of 10-20 mm and fitted with a compression fitting. The linear structure of the glass fiber strip is sealed and embedded in the water inlet of the evaporator 21 through the compression fitting. The other end of the glass fiber strip, away from the compression fitting, hangs naturally in the direction of a plumb line inside the evaporator 21, thereby uniformly delivering deionized water from the water inlet to the surface of the glass fiber strip.

[0038] When water vapor is required, deionized water is first directly filled into the water storage tank 11. Then, the controller issues an instruction to start heating the first heating tape 24 and the second heating tape 25, using the heating tape to heat the carrier gas preheating pipe 23 and the evaporator 21 to the target temperature. Next, the controller synchronously opens the carrier gas flow meter 31, the water injection control valve 33, and starts the medium-pressure constant flow pump 12 to synchronously introduce the required N2 and deionized water into the evaporator 21. N2 is first preheated by the carrier gas preheating pipe 23, and then the preheated evaporator 21 rapidly vaporizes the deionized water adsorbed on the surface of the glass fiber belt (i.e., the distributor 22). The generated water vapor and N2 are mixed and released from the pipe connected to the steam release port at the bottom of the evaporator 21 to form a simulated gas mixture. Finally, a catalyst is introduced to react, and the gas after reaction is introduced into an analyzer for concentration analysis.

[0039] When it is necessary to stop the supply of steam, the controller can be used to close the carrier gas flow meter 31, the water injection control valve 33, and stop the medium-pressure constant flow pump 12, thereby stopping the output of steam.

[0040] The medium-pressure constant flow pump 12 executes the instruction to deliver deionized water at a flow rate (unit: ml / min). However, in actual simulated atmosphere gas mixing, the required concentration of water vapor in the atmosphere output from the steam release port of the evaporator 21 is the design concentration (unit: %). Therefore, it is necessary to calculate the flow rate corresponding to the required water vapor concentration, which can be done using the following conversion formula: ,

[0041] In the formula: V 液态水 The water supply flow rate of the medium-pressure constant flow pump 12 is expressed in mL / min. V 总流量 The total flow rate of the atmosphere output from the vapor release port of evaporator 21, in mL / min; C 水蒸气 The design concentration of water vapor in the output atmosphere from the steam release port of evaporator 21, in % (%). ρ 水This is the density of water, expressed in g / cm³. 3 ; 18 is the molar mass of water, in g / mol; 22.4 represents the molar volume of the gas under standard conditions, in L / mol.

[0042] This embodiment calculates the required water supply flow rate for several different water vapor concentrations using the above conversion formula, and performs simulated atmosphere gas mixing according to the above embodiment to obtain... Figure 3 The graphs showing different water vapor concentrations versus time, and Table 1 showing the correspondence between the water supply flow rate and water vapor concentration of the medium-pressure constant flow pump 12.

[0043] Table 1 Correspondence between water supply flow rate and water vapor concentration

[0044] From Table 1 and Figure 3 It can be seen that the high-precision steam vaporization device for stable gas supply of the present invention produces steam with good stability under long-term supply. The theoretically calculated water flow rate and the actual generated steam concentration have a good correspondence, indicating that the device has good vaporization performance and can provide accurate and stable steam flow rate.

[0045] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A high-precision steam vaporization device for experimental use with stable gas supply, characterized in that: It includes a liquid delivery unit (1), a vaporization unit (2), and a control unit (3). The liquid delivery unit (1) includes a water storage tank (11) and a medium-pressure constant flow pump (12). The inlet of the medium-pressure constant flow pump (12) is connected to the outlet of the water storage tank (11) through a pipe. The vaporization unit (2) includes an evaporator (21), a distributor (22), a carrier gas preheating pipe (23), and a heat tracing cable. The evaporator (21) is an inclined columnar sealed tank with a carrier gas inlet at the top and a steam release port at the bottom. The distributor (22) is made of water-absorbing material and is suspended inside the evaporator (21), with one end fixedly connected to the water inlet on the side of the evaporator (21). The water inlet of the evaporator (21) is connected to the liquid outlet of the medium-pressure constant flow pump (12) through a pipe. The carrier gas preheating pipe (23) is connected to the carrier gas inlet at the top of the evaporator (21). The end of the carrier gas preheating pipe (23) away from the carrier gas inlet of the evaporator (21) is connected to the carrier gas supply device through a pipe. The heat tracing cable is fixedly installed on the outer walls of the evaporator (21) and the carrier gas preheating pipe (23). The control unit (3) includes a carrier gas flow meter (31), a carrier gas control valve (32), a water injection control valve (33), and a controller. The carrier gas flow meter (31) and the carrier gas control valve (32) are respectively installed on the pipeline connecting the carrier gas preheating pipe (23) and the carrier gas supply device. The water injection control valve (33) is installed on the pipeline connecting the water inlet of the evaporator (21) and the medium-pressure constant flow pump (12). The controller is electrically connected to the carrier gas flow meter (31), the carrier gas control valve (32), the water injection control valve (33), the medium-pressure constant flow pump (12), and the heating tape.

2. The high-precision steam vaporization device for stable gas supply as described in claim 1, characterized in that: The evaporator (21) is a columnar sealed tank with its central axis inclined at 30 to 60 degrees to the ground. The water inlet of the evaporator (21) is located in the upper middle part of the side wall of the evaporator (21). One end of the distributor (22) is fixedly connected to the water inlet of the evaporator (21) and the other end hangs inside the evaporator (21).

3. The high-precision steam vaporization device for stable gas supply according to claim 2, characterized in that: The distributor (22) is a glass fiber belt, rock wool fiber belt or ceramic fiber belt. One end of the distributor (22) is twisted into a linear structure and fitted with a compression fitting. The distributor (22) is sealed and embedded in the water inlet of the evaporator (21) through the compression fitting. The other end of the distributor (22) away from the compression fitting hangs naturally in the evaporator (21) along the plumb line.

4. The high-precision steam vaporization device for stable gas supply as described in claim 3, characterized in that: The distributor (22) is twisted into a linear structure, with one end extending 10-20 mm into the water inlet of the evaporator (21). The side of the distributor (22) away from the water inlet of the evaporator (21) hangs down naturally in the direction of a plumb line, and the bottom end does not contact the inner wall of the evaporator (21).

5. The high-precision steam vaporization device for stable gas supply according to claim 2, characterized in that: The outlet pipe of the water storage tank (11) is connected to a filter head or is equipped with a filter screen, and the liquid flow rate of the outlet of the medium pressure constant flow pump (12) does not exceed 10.00 ml / min.

6. The high-precision steam vaporization device for stable gas supply according to any one of claims 1 to 5, characterized in that: The heat tracing cable includes a first heat tracing cable (24) and a second heat tracing cable (25). The first heat tracing cable (24) is fixedly installed on the outer wall of the evaporator (21) and has a first thermocouple built in it. The second heat tracing cable (25) is fixedly installed on the outer wall of the carrier gas preheating pipe (23) and has a second thermocouple built in it. The first thermocouple and the second thermocouple are electrically connected to the controller.

7. The high-precision steam vaporization device for stable gas supply according to claim 6, characterized in that: The heating temperature of the first heat tracing cable (24) and the second heat tracing cable (25) shall not exceed 300°C and shall not be lower than 180°C. The control setting temperature of the first heat tracing cable (24) and the second heat tracing cable (25) shall be consistent.

8. The high-precision steam vaporization device for stable gas supply according to claim 6, characterized in that: The outer wall of the evaporator (21) is wrapped with a first insulation strip (26), and the first heat tracing tape (24) is wrapped inside the first insulation strip (26); the outer wall of the carrier gas preheating pipe (23) is wrapped with a second insulation strip (27), and the second heat tracing tape (25) is wrapped inside the second insulation strip (27); the pipe connected to the steam release port at the bottom of the evaporator (21) is wrapped with a third insulation strip (28).

9. The high-precision steam vaporization device for stable gas supply according to claim 6, characterized in that: The water supply flow rate of the medium-pressure constant flow pump (12) V 液态水 for: ， In the formula: V 液态水 The unit is mL / min; V 总流量 The total flow rate of the atmosphere output from the vapor release port of the evaporator (21), in mL / min; C 水蒸气 The design concentration of water vapor in the output atmosphere of the steam release port of the evaporator (21), in %; ρ 水 This is the density of water, expressed in g / cm³. 3 .

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