Ultra-pure ammonia filling system and process

Abstract

The invention provides an ultra-pure ammonia filling system. The ultra-pure ammonia filling system comprises an ultra-pure ammonia product tank, an automatic regulating valve, a precooler, a shield pump, a filling row and a packaging container, in the first filling process, liquid ammonia self-flowing filling is achieved by controlling the pressure difference between a product tank and a packaging container, meanwhile, a liquid ammonia storage tank is arranged at a certain height, the gravity difference is increased, and the filling speed is increased. In order to ensure that the temperature is in a low range in the filling process and prevent the filling speed from being reduced due to high pressure in the packaging container, a precooler is arranged on a filling pipeline for cooling liquid ammonia. And the filling process II is to carry out liquid-phase filling by using a shield pump. According to the invention, the original filling operation is simplified, the filling process suitable for the ultra-pure ammonia is determined, and two ultra-pure ammonia filling process flows with different filling rates are provided. In addition, the problems of the treatment method, the treatment device and the treatment temperature of the ultra-pure ammonia steel cylinder are solved. It is verified that the ultra-pure ammonia product can be stably, efficiently and safely filled.

Description

Technical Field

[0001] This invention relates to the field of ultrapure product filling technology, and in particular to an ultrapure ammonia filling system and process. Background Technology

[0002] Ultrapure ammonia, as an important electronic gas, is an ideal nitrogen source and is often used in the synthesis of nitrides. It has wide applications in semiconductor integrated circuits (ICs), liquid crystal displays (LCDs), semiconductor light-emitting devices (LEDs), and solar cells (PVs). In the LED industry, ultrapure ammonia is used as a nitrogen source to prepare gallium nitride (GaN), the foundation of LEDs. The higher the purity of the ammonia used, the lower the power consumption and the greater the luminous intensity of the LED. Ultrapure ammonia is also used as a nitrogen source to prepare chemical vapor deposition (CVD) silicon nitride (Si3N4) insulating layers, which are widely used in large-scale integrated circuits and LCDs. Furthermore, ultrapure ammonia is used as a nitrogen source to prepare silicon nitride (Si3N4) anti-emission coatings, which are deposited on the surface of crystalline silicon solar cells to increase the absorption of sunlight by the cells.

[0003] In recent years, with the increasing market demand for ultrapure ammonia, purification processes for ultrapure ammonia have emerged continuously. To synthesize high-quality nitrides, industries such as microelectronics have increasingly stringent purity requirements for ultrapure ammonia. For example, the national standard for ultrapure ammonia has evolved from 5N5 to 6N4, and now the market demand for 7N ultrapure ammonia is expanding significantly. Therefore, the requirements for the filling process and cylinder handling methods of 7N ultrapure ammonia are also increasing.

[0004] Meanwhile, since ammonia is a flammable and explosive gas, which is quite dangerous, the stability of safety is also a key aspect that needs to be examined in the filling process. Summary of the Invention

[0005] In view of this, in order to provide an efficient, stable and safe filling system and process for ultrapure ammonia products.

[0006] The technical solution of this invention:

[0007] An ultrapure ammonia filling system includes: a product tank for storing ultrapure ammonia, the outlet of the product tank being connected to an automatic regulating valve and a shielded pump, the automatic regulating valve and the shielded pump being arranged in parallel, the outlet of the automatic regulating valve being connected to a precooler, the outlets of the shielded pump and the precooler being connected to a filling manifold, the filling manifold being connected to a packaging container, and a filling valve being provided in front of the packaging container.

[0008] The precooler is connected to the refrigerant inlet pipeline and the refrigerant outlet pipeline;

[0009] The filling station is equipped with a return liquid line, a gas phase balance line, a displacement helium line, a vacuum line, an analysis line, and gas phase and liquid phase lines connecting to the packaging container.

[0010] Preferably, the refrigerant inlet pipeline, outlet pipeline, return liquid pipeline, gas phase balance pipeline, displacement helium pipeline, vacuum pipeline, analysis pipeline, as well as the gas phase pipeline and liquid phase pipeline connecting the packaging container, all use electrochemically polished tubes to ensure that no impurities are introduced during the product packaging process; the inner wall of the packaging container is ground and passivated to prevent the inner wall from reacting with the product gas.

[0011] Preferably, the packaging container is an ultrapure ammonia T-bottle or an ultrapure ammonia tank container.

[0012] Preferably, the ultrapure ammonia T-bottle is pretreated before filling. The pretreatment method is as follows: the temperature of the heating pack of the ultrapure ammonia T-bottle is set to 35°C, 40°C and 45°C respectively; the gas phase valve and liquid phase valve of the ultrapure ammonia T-bottle are opened; the filling drain valve of the ultrapure ammonia T-bottle is opened; the cylinder is evacuated; after the filling drain pressure drops to -0.085MPa, it is maintained for 15 to 30 minutes to release the gas adsorbed on the inner wall of the new cylinder.

[0013] Close the filling and drain valve of the ultrapure ammonia T-cylinder, fill the cylinder with 7N ultrapure ammonia to pressures of 0.2MPa, 0.3MPa, 0.4MPa, and 0.5MPa respectively, let it stand for more than 10 minutes to allow the gas to mix evenly, and then evacuate the cylinder to a pressure ≤ -0.085MPa; repeat the evacuation and replacement 3 to 7 times.

[0014] An ultrapure ammonia filling process includes the following steps: the product tank is located at a high position of the filling pump, the filling rate is controlled by an automatic regulating valve, the ultrapure ammonia is cooled by a precooler, and the packaging container is filled by the filling pump. The filling process is liquid phase filling.

[0015] The return pipeline returns the liquid ultrapure ammonia from the packaging container or filling drain to the liquid phase loop in the system, balancing the liquid phase medium in the system and ensuring the stability of the filling process.

[0016] The gas phase balance pipeline balances the gas phase pressure of the packaging container or filling outlet. The gas phase balance pipeline is connected to the buffer tank so that ultrapure ammonia can be filled smoothly and avoid the filling rate from decreasing or the equipment from being damaged due to the small pressure difference in the later stage.

[0017] Helium is introduced into the replacement helium pipeline to replace the packaging container, filling valve and related pipelines, and then the helium is discharged through other pipelines with the assistance of the replacement helium.

[0018] The vacuum line uses a vacuum pump to evacuate the packaging container, filling pump and related pipelines to remove gaseous impurities, further ensuring the purity of the ultrapure ammonia after filling.

[0019] The analytical pipeline carries ultrapure ammonia samples from the filling drain or packaging container to the analytical instrument for chemical analysis and detection.

[0020] To prevent liquid ammonia from vaporizing, to ensure that the temperature remains within a low range during the filling process, and to prevent high pressure inside the packaging container from reducing the filling rate, a precooler is installed to cool the liquid ammonia.

[0021] Preferably, the temperature of the product tank is 10–30°C and the pressure is 0.7–0.9 MPa;

[0022] Chemical indicators include purity and metal ions.

[0023] Preferably, the temperature of the refrigerant in the precooler is -30 to -20°C. The refrigerant cools the precooler through the refrigerant inlet pipeline and then is discharged through the refrigerant outlet pipeline.

[0024] Preferably, the filling rate is controlled at 300-380 kg / h by an automatic regulating valve.

[0025] An ultrapure ammonia filling process includes the following steps: ultrapure ammonia in the product tank is transported to the filling pump using a shielded pump, and the filling pump is used to fill the packaging container. The filling process is liquid phase filling.

[0026] Preferably, the flow rate of the shielded pump used for filling is 5m³ / h. 3 / h shielded pump, filling rate is 800~3000kg / h.

[0027] The ultrapure ammonia filling process has two methods. Method one achieves gravity-flow filling of liquid ammonia by controlling the pressure difference between the product tank and the packaging container. Simultaneously, the liquid ammonia storage tank is positioned at a certain height to increase the gravity difference and improve the filling rate. To ensure the temperature remains low during filling and prevent high pressure inside the packaging container from reducing the filling rate, a pre-cooler is installed on the filling pipeline to cool the liquid ammonia.

[0028] Method two involves using a canned pump for liquid phase filling.

[0029] The process piping uses electrochemically polished tubing to ensure no impurities are introduced during product packaging; the vacuum system maintains a high vacuum level; and the inner wall of the packaging container undergoes grinding and passivation treatment to prevent further reaction with the product gas. This avoids the introduction of metal ions that could cause product defects. The ultrapure ammonia filling method one uses an automatic regulating valve to control the filling rate. To prevent liquid ammonia vaporization, a precooler is installed on the filling pipeline to cool the liquid ammonia.

[0030] The beneficial effects of this invention are:

[0031] This invention provides two ultrapure ammonia filling process flows with different filling rates, ensuring stable, efficient, and safe filling of ultrapure ammonia products.

[0032] This invention studies the influence of the inner wall condition of steel cylinders on the cylinder replacement treatment effect and key indicators of cylinder moisture removal, and formulates a cylinder treatment process to ensure the filling of ultrapure ammonia, thus laying the groundwork for the subsequent industrialization of 7N ultrapure ammonia in the market. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below. The drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention.

[0034] Figure 1 This is a schematic diagram of the filling system of the present invention.

[0035] List of reference numerals in the attached diagram:

[0036] 1. Product tank; 2. Automatic regulating valve; 3. Shielded pump; 4. Precooler; 5. Filling valve; 6. Packaging container; S1. Refrigerant inlet pipeline; S2. Refrigerant outlet pipeline; S3. Liquid return pipeline; S4. Gas phase balance pipeline; S5. Replacement helium pipeline; S6. Vacuum pipeline; S7. Analysis pipeline. Detailed Implementation

[0037] To make the objectives, solutions, and advantages of the present invention clearer, the following description will be provided in conjunction with specific embodiments of the present invention. Figure 1 The technical solutions of the embodiments of the present invention will be clearly and completely described herein. Unless otherwise stated, the terminology used herein has its ordinary meaning in the art. The same reference numerals in the drawings represent the same parts.

[0038] Device Examples

[0039] An ultrapure ammonia filling system includes: a product tank 1 for storing ultrapure ammonia, the outlet of the product tank 1 being connected to an automatic regulating valve 2 and a shielded pump 3, the automatic regulating valve 2 and the shielded pump 3 being arranged in parallel, the outlet of the automatic regulating valve 2 being connected to a precooler 4, the outlets of the shielded pump 3 and the precooler 4 being connected to a filling manifold 5, the filling manifold 5 being connected to a packaging container 6, and a filling valve being provided in front of the packaging container 6;

[0040] The precooler 4 is connected to the refrigerant inlet pipeline S1 and the refrigerant outlet pipeline S2;

[0041] The filling line 5 is equipped with a return liquid line S3, a gas phase balance line S4, a displacement helium line S5, a vacuum line S6, an analysis line S7, and gas phase and liquid phase lines connecting to the packaging container 6.

[0042] The refrigerant inlet pipeline S1, outlet pipeline S2, return liquid pipeline S3, gas phase balance pipeline S4, displacement helium pipeline S5, vacuum pipeline S6, analysis pipeline S7, as well as the gas phase pipeline and liquid phase pipeline connecting the packaging container 6, all use electrochemically polished tubes, and the inner wall of the packaging container 6 is ground and passivated.

[0043] Method 1, Example 1:

[0044] An ultrapure ammonia filling process includes a product tank 1 with a temperature of 30°C and a pressure of 0.8 MPa. The product tank 1 is located at a higher position than the filling pump 5, 3m above the pump. The filling rate is controlled by an automatic regulating valve 2. A precooler 4 is used to cool the ultrapure ammonia. The temperature of the refrigerant (ethylene glycol aqueous solution) in the precooler is -30°C. The refrigerant cools the precooler through the refrigerant inlet pipeline S1 and then is discharged through the refrigerant outlet pipeline S2. The filling pump 5 is used to fill packaging containers 6, and the filling process involves liquid phase filling.

[0045] The return line S3 returns the liquid phase ultrapure ammonia in the packaging container 6 or the filling drain 5 to the liquid phase loop in the system.

[0046] The gas phase balancing line S4 balances the gas phase pressure of the packaging container 6 or the filling drain 5.

[0047] After helium gas is introduced into the replacement helium pipeline S5 to replace the packaging container 6, filling valve 5 and related pipelines, the helium gas is discharged through other pipelines.

[0048] Vacuum line S6 uses a vacuum pump to evacuate the packaging container 6, filling outlet 5 and related pipelines, removing gaseous impurities.

[0049] The analysis line S7 draws ultrapure ammonia samples from the filling drain 5 or packaging container 6 to the analytical instrument for analysis and detection of indicators.

[0050] By controlling the automatic regulating valve 2, the weight of bottle T is filled to 480kg at a filling rate of 380kg / h. The filling process is liquid phase filling. There are no abnormalities during normal filling. After filling, the product indicators meet the requirements, as shown in Table 1.

[0051] Table 1

[0052]

[0053] Method 1, Example 2:

[0054] An ultrapure ammonia filling process includes a product tank 1 with a temperature of 10°C and a pressure of 0.9 MPa. The product tank 1 is located at a higher position than the filling pump 5, 3m above the pump. The filling rate is controlled by an automatic regulating valve 2. A precooler 4 is used to cool the ultrapure ammonia. The temperature of the refrigerant (liquid ammonia) in the precooler is -20°C. The refrigerant cools the precooler through a refrigerant inlet pipeline S1 and then exits through a refrigerant outlet pipeline S2. The filling pump 5 is used to fill packaging containers 6, and the filling process involves liquid phase filling.

[0055] The return line S3 returns the liquid phase ultrapure ammonia in the packaging container 6 or the filling drain 5 to the liquid phase loop in the system.

[0056] The gas phase balancing line S4 balances the gas phase pressure of the packaging container 6 or the filling drain 5.

[0057] After helium gas is introduced into the replacement helium pipeline S5 to replace the packaging container 6, filling valve 5 and related pipelines, the helium gas is discharged through other pipelines.

[0058] Vacuum line S6 uses a vacuum pump to evacuate the packaging container 6, filling outlet 5 and related pipelines, removing gaseous impurities.

[0059] The analysis line S7 draws ultrapure ammonia samples from the filling drain 5 or packaging container 6 to the analytical instrument for analysis and detection of indicators.

[0060] By controlling the automatic regulating valve 2, the T bottle is filled to a weight of 480 kg at a filling rate of 300 kg / h. The filling process is liquid phase filling. Normal filling is normal and there are no abnormalities. After filling is completed, the product indicators meet the requirements, as shown in Table 2.

[0061] Table 2

[0062]

[0063] Method 1, Example 3:

[0064] An ultrapure ammonia filling process includes a product tank 1 with a temperature of 20°C and a pressure of 0.7 MPa. The product tank 1 is located at a higher position than the filling pump 5, 3m above the pump. The filling rate is controlled by an automatic regulating valve 2. A precooler 4 is used to cool the ultrapure ammonia. The temperature of the refrigerant (liquid ammonia) in the precooler is -25°C. The refrigerant cools the precooler through a refrigerant inlet pipeline S1 and then exits through a refrigerant outlet pipeline S2. The filling pump 5 is used to fill packaging containers 6, and the filling process involves liquid phase filling.

[0065] The return line S3 returns the liquid phase ultrapure ammonia in the packaging container 6 or the filling drain 5 to the liquid phase loop in the system.

[0066] The gas phase balancing line S4 balances the gas phase pressure of the packaging container 6 or the filling drain 5.

[0067] After helium gas is introduced into the replacement helium pipeline S5 to replace the packaging container 6, filling valve 5 and related pipelines, the helium gas is discharged through other pipelines.

[0068] Vacuum line S6 uses a vacuum pump to evacuate the packaging container 6, filling outlet 5 and related pipelines, removing gaseous impurities.

[0069] The analysis line S7 draws ultrapure ammonia samples from the filling drain 5 or packaging container 6 to the analytical instrument for analysis and detection of indicators.

[0070] By controlling the automatic regulating valve 2, the T bottle is filled to a weight of 480 kg at a filling rate of 350 kg / h. The filling process is liquid phase filling. Normal filling is normal and there are no abnormalities. After filling is completed, the product indicators meet the requirements, as shown in Table 3.

[0071] Table 3

[0072]

[0073] Method 2 Example 1:

[0074] An ultrapure ammonia filling process uses a shielded pump 3 for liquid phase filling. The use of the shielded pump 3 in the conveying equipment effectively prevents leakage. A high-precision liquid phase filter is installed before the shielded pump 3 to effectively remove particles from the product and prevent the introduction of metal ions that could cause product defects.

[0075] The specific filling steps are as follows: Before filling, open the gas and liquid phase valves of the ultrapure ammonia tank container. After confirming that the pressure is normal, start the shielded pump 3 to begin filling. The flow rate of the shielded pump used for filling is 5m³ / h. 3 The system uses a shielded pump with a filling rate of 800 kg / h. During filling, if the pressure in the ultrapure ammonia cylinder T increases, the gas phase balance line valve S4 is opened to release some of the gas phase back into the buffer tank to balance the pressure. During filling, the analysis line S7 needs to perform online component analysis regularly and record key parameters such as pressure and weight. When the filling weight reaches the target value, the system interlocks and closes the filling valve before the packaging container 6. Subsequently, the liquid phase and gas phase pipeline valves of the ultrapure ammonia cylinder T are closed sequentially. After filling is completed, samples are taken for analysis, and all key purity indicators meet the requirements of the ultrapure ammonia standard, as shown in Table 4.

[0076] Table 4

[0077]

[0078] Method 2, Example 2:

[0079] The specific filling steps are as follows: Before filling, open the gas and liquid phase valves of the ultrapure ammonia tank container. After confirming that the pressure is normal, start the shielded pump 3 to begin filling. The flow rate of the shielded pump used for filling is 5m³ / h. 3 The system uses a shielded pump with a filling rate of 3000 kg / h. During filling, if the pressure in the ultrapure ammonia cylinder T increases, the gas phase balance line valve S4 is opened to release some of the gas phase back into the buffer tank to balance the pressure. During filling, the analysis line S7 needs to perform online component analysis regularly and record key parameters such as pressure and weight. When the filling weight reaches the target value, the system interlocks and closes the filling valve before the packaging container 6. Subsequently, the liquid phase and gas phase pipeline valves of the ultrapure ammonia cylinder T are closed sequentially. After filling is completed, samples are taken for analysis, and all key purity indicators meet the requirements of the ultrapure ammonia standard, as shown in Table 5.

[0080] Table 5

[0081]

[0082] Method 2, Example 3:

[0083] The specific filling steps are as follows: Before filling, open the gas and liquid phase valves of the ultrapure ammonia tank container. After confirming that the pressure is normal, start the shielded pump 3 to begin filling. The flow rate of the shielded pump used for filling is 5m³ / h. 3 The system uses a shielded pump with a filling rate of 1000 kg / h. During filling, if the pressure in the ultrapure ammonia cylinder T increases, the gas phase balance line valve S4 is opened to release some of the gas phase back into the buffer tank to balance the pressure. During filling, the analysis line S7 needs to perform online component analysis regularly and record key parameters such as pressure and weight. When the filling weight reaches the target value, the system interlocks and closes the filling valve before the packaging container 6. Subsequently, the liquid phase and gas phase pipeline valves of the ultrapure ammonia cylinder T are closed sequentially. After filling is completed, samples are taken for analysis, and all key purity indicators meet the requirements of the ultrapure ammonia standard, as shown in Table 6.

[0084] Table 6

[0085]

[0086] Examples of treatment methods for the ultrapure ammonia T-bottles used in Methods 1 and 2:

[0087] This embodiment also provides a method for treating ultrapure ammonia cylinders under different heating pack temperatures and different passivation pressures of ultrapure ammonia T-bottles. The specific treatment and filling steps are as follows:

[0088] Set the heating pack temperature of the ultrapure ammonia T-cylinder to 35℃, 40℃, and 45℃ respectively. Open the gas phase valve and liquid phase valve of the ultrapure ammonia T-cylinder, open the filling drain valve of the ultrapure ammonia T-cylinder, and evacuate the cylinder. After the filling drain pressure drops to -0.085MPa, maintain it for 10 to 30 minutes to release any gas that may have been adsorbed on the inner wall of the new cylinder.

[0089] Close the filling and drain valve of the ultrapure ammonia T-cylinder, and fill the cylinder with 7N ultrapure ammonia to pressures of 0.2MPa, 0.3MPa, 0.4MPa, and 0.5MPa respectively. Let it stand for at least 10 minutes to allow the gas to mix evenly. Evacuate the cylinder to a pressure ≤ -0.085MPa; repeat the evacuation and replacement process 3, 4, 5, 6, and 7 times respectively.

[0090] After the final evacuation, the cylinder was filled with 7N ultrapure ammonia to a pressure of 0.4–0.7 MPa. The cylinder valve was closed, and the cylinder was allowed to stand for at least 24 hours. Empty cylinder chromatography and moisture analysis were then performed. The results validated that, under conditions of 40°C, filling the cylinder with 7N ultrapure ammonia to a pressure of 0.4 MPa, and repeating the evacuation and replacement process five times, the test results all met the quality standards for 7N ultrapure ammonia products, and the amount of ultrapure ammonia used for passivation was minimized. This validation determined the optimal temperature for cylinder treatment and revealed a treatment method that requires less ultrapure ammonia and shorter replacement time at this temperature.

[0091] Finally, it should be noted that when describing the positions of various components and their mating relationships, this invention typically uses one or a pair of components as examples. However, those skilled in the art should understand that such positions and mating relationships also apply to other components or other pairs of components. The above descriptions are merely exemplary embodiments of this invention and are not intended to limit the scope of protection of this invention, which is determined by the appended claims.

Claims

1. An ultrapure ammonia filling system, characterized in that, include: A product tank (1) for storing ultrapure ammonia, wherein the outlet of the product tank (1) is connected to an automatic regulating valve (2) and a shielded pump (3), wherein the automatic regulating valve (2) and the shielded pump (3) are arranged in parallel, wherein the outlet of the automatic regulating valve (2) is connected to a precooler (4), wherein the outlets of the shielded pump (3) and the precooler (4) are connected to a filling manifold (5), wherein the filling manifold (5) is connected to a packaging container (6), wherein a filling valve is provided in front of the packaging container (6); The precooler (4) is connected to the refrigerant inlet pipeline (S1) and the refrigerant outlet pipeline (S2); The filling line (5) is provided with a return liquid line (S3), a gas phase balance line (S4), a displacement helium line (S5), a vacuum line (S6), an analysis line (S7), and a gas phase line and a liquid phase line connecting the packaging container (6).

2. The ultrapure ammonia filling system according to claim 1, characterized in that, The refrigerant inlet pipeline (S1), outlet pipeline (S2), return liquid pipeline (S3), gas phase balance pipeline (S4), displacement helium pipeline (S5), vacuum pipeline (S6), analysis pipeline (S7), as well as the gas phase pipeline and liquid phase pipeline connecting the packaging container (6), all use electrochemical polishing tubes, and the inner wall of the packaging container (6) is ground and passivated.

3. The ultrapure ammonia filling system according to claim 1, characterized in that, The packaging container (6) is an ultrapure ammonia T-bottle or an ultrapure ammonia tank container.

4. The ultrapure ammonia filling system according to claim 3, characterized in that, The ultrapure ammonia T-bottle needs to be pretreated before filling. The pretreatment method is as follows: set the heating temperature of the ultrapure ammonia T-bottle to 35℃, 40℃ and 45℃ respectively, open the gas phase valve and liquid phase valve of the ultrapure ammonia T-bottle, open the filling drain valve of the ultrapure ammonia T-bottle, evacuate the cylinder, and after the filling drain pressure drops to -0.085MPa, maintain it for 15-30 minutes to release the gas adsorbed on the inner wall of the new cylinder. Close the filling and drain valve of the ultrapure ammonia T-cylinder, fill the cylinder with 7N ultrapure ammonia to pressures of 0.2MPa, 0.3MPa, 0.4MPa, and 0.5MPa respectively, let it stand for more than 10 minutes to allow the gas to mix evenly, and then evacuate the cylinder to a pressure ≤ -0.085MPa; repeat the evacuation and replacement 3 to 7 times.

5. An ultrapure ammonia filling process, employing the ultrapure ammonia filling system described in claim 1, characterized in that, The process includes the following steps: the product tank (1) is located at the high position of the filling row (5), the filling rate is controlled by the automatic regulating valve (2), the ultrapure ammonia is cooled by the precooler (4), and the packaging container (6) is filled by the filling row (5). The filling process is liquid phase filling. The return line (S3) returns the liquid phase ultrapure ammonia in the packaging container (6) or filling drain (5) to the liquid phase loop in the system; A gas phase balancing line (S4) balances the gas phase pressure of the packaging container (6) or the filling outlet (5), and the gas phase balancing line (S4) is connected to a buffer. After the helium gas is replaced by helium gas through the replacement helium pipeline (S5) to replace the packaging container (6), filling outlet (5) and related pipelines, the helium gas is discharged through other pipelines. The vacuum line (S6) uses a vacuum pump to evacuate the packaging container (6), filling outlet (5) and related pipelines to remove gaseous impurities. The analysis line (S7) draws ultrapure ammonia samples from the filling drain (5) or packaging container (6) to the analytical instrument for chemical analysis and detection.

6. The ultrapure ammonia filling process according to claim 5, characterized in that, The product tank (1) has a temperature of 10-30°C and a pressure of 0.7-0.9 MPa; Chemical indicators include purity and metal ions.

7. The ultrapure ammonia filling process according to claim 5, characterized in that, The temperature of the refrigerant in the precooler (4) is -30 to -20℃. The refrigerant cools the precooler (4) through the refrigerant inlet pipeline (S1) and then the refrigerant is discharged through the refrigerant outlet pipeline (S2).

8. The ultrapure ammonia filling process according to claim 5, characterized in that, The filling rate is controlled to be 300-380 kg / h by an automatic regulating valve (2).

9. An ultrapure ammonia filling process, employing the ultrapure ammonia filling system described in claim 1, characterized in that, The process includes the following steps: the ultrapure ammonia in the product tank (1) is transported to the filling pump (5) by the shielded pump (3), and the packaging container (6) is filled by the filling pump (5). The filling process is liquid phase filling.

10. The ultrapure ammonia filling process according to claim 9, characterized in that, The canned pump (3) used for filling has a flow rate of 5m³ / h. 3 / h shielded pump, filling rate is 800~3000kg / h.

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