Method for safely activating vaporization system of helium expansion refrigeration hydrogen liquefaction station before liquid discharge

Abstract

The invention belongs to the technical field of hydrogen liquefaction, and provides a safe activation method before liquid discharge of a vaporization system of a helium expansion refrigeration hydrogen liquefaction station, which comprises the following steps: activating a first-stage condensation filter; performing activation of the second stage coagulation filter; determining whether the activation of the first and second-stage coagulation filters of the oil removal system and the activation of the cold trap can be carried out at the same time; and ending the activation of the first-stage coagulation filter and the second-stage coagulation filter according to the initial preparation activation duration of the first-stage coagulation filter of the oil removal system, the initial preparation activation duration of the second-stage coagulation filter of the oil removal system and the coagulation filter activation near-saturation time. In the process of carrying out safety assessment on the vaporization system for the hydrogen liquefaction station to discharge liquid, the vaporization safety of liquid nitrogen used as nitrogen for activating a secondary coagulation filter and a cold trap of an oil removal system is judged, so that the safety assessment function of the vaporization system for the hydrogen liquefaction station is richer and more perfect; and the safety guarantee level of the hydrogen liquefaction system can be improved to a certain extent.

Description

Technical Field

[0001] This disclosure pertains to the field of hydrogen liquefaction technology, and particularly relates to a method, system, equipment, medium, and product for safe activation of a helium expansion refrigeration hydrogen liquefaction station vaporization system before liquid discharge. Background Technology

[0002] Liquid hydrogen is an optimized choice for large-scale, long-distance hydrogen-electric coupling commercial applications due to its high hydrogen carrying capacity, low long-distance transportation cost, and small equipment and system size during the transfer, injection, storage and transportation process. Hydrogen liquefaction technology is a key link in the application of hydrogen energy as a potential medium for large-scale and dense energy storage in the power sector.

[0003] In a hydrogen liquefaction system employing helium expansion refrigeration, the incident hydrogen stream to be refrigerated is pre-cooled by cryogenic nitrogen or a combination of liquid nitrogen and / or mixed working fluids. Further cryogenic cooling of the pre-cooled hydrogen stream requires a reverse Brayton cycle refrigerator, using compressed helium as the circulating working medium to generate the required cryogenic temperature for liquefied hydrogen, gradually reaching the hydrogen condensation temperature range. Finally, liquid hydrogen is obtained through the throttling expansion of the cryogenic hydrogen.

[0004] In the process of testing, commissioning, demonstration application and even actual production of hydrogen liquefaction systems using helium expansion refrigeration, to ensure the safe, efficient and stable operation of the entire hydrogen liquefaction system, it is not only important to manage the vaporization process of the precooling agent used for precooling liquid hydrogen and the vaporization process of liquid hydrogen products used for precooling-free hydrogen sources, but also the vaporization process within the hydrogen liquefaction station that is not directly used for product preparation.

[0005] Currently, there are no technical solutions for the safe activation of the vaporization system used in helium-cooled hydrogen liquefaction stations before producing liquid hydrogen products (i.e., liquid output) for hydrogen liquefaction systems that use helium expansion refrigeration. Summary of the Invention

[0006] To address the aforementioned issues, this disclosure provides a method for pre-discharge safety activation of the vaporization system of a helium expansion refrigeration hydrogen liquefaction station. During the safety assessment of the vaporization system of the hydrogen liquefaction station to be liquefied, the safety of liquid nitrogen vaporization used as the nitrogen for activation of the secondary condensation filter and cold trap in the oil removal system is determined. This method enriches and improves the safety assessment function of the vaporization system of the hydrogen liquefaction station, thereby enhancing the safety assurance level of the hydrogen liquefaction system to a certain extent.

[0007] In a first aspect, this disclosure provides a method for pre-discharge safety activation of a helium expansion refrigeration hydrogen liquefaction station vaporization system, comprising: The activation of the first-stage coagulation filter is performed based on the real-time mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system. The activation of the second-stage coagulation filter is performed based on the initial activation duration of the first-stage coagulation filter in the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system. Based on the real-time mass flow rate of nitrogen used for cold trap activation, determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be carried out simultaneously. Based on the initial activation duration of the first-stage coagulation filter in the oil removal system, the initial activation duration of the second-stage coagulation filter in the oil removal system, and the near-saturation time of the coagulation filter activation, the activation of the first-stage and second-stage coagulation filters is terminated.

[0008] Furthermore, Based on the real-time mass flow rate of nitrogen used for activating the first-stage condensate filter in the oil removal system, activation of the first-stage condensate filter is performed, including: Start the vaporization of liquid nitrogen stored in the vaporization station and monitor the real-time mass flow rate of nitrogen used for activation of the first-stage condensation filter in the oil removal system; The operation of the first-stage coagulation filter is determined based on the real-time mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system and the minimum threshold mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system.

[0009] Furthermore, Based on the initial activation duration of the first-stage coagulation filter in the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system, activation of the second-stage coagulation filter is performed, including: If the activation duration does not reach the initial preparation activation duration, the first-stage coagulation filter will continue to be activated until the initial preparation activation duration of the first-stage coagulation filter is reached. The activation of the second-stage condensate filter is performed based on the real-time mass flow rate of nitrogen used for activation of the second-stage condensate filter in the oil removal system.

[0010] Furthermore, A control valve is installed between the first-stage condensate filter and the second-stage condensate filter. The second-stage condensate filter can only be activated after the control valve is opened.

[0011] Furthermore, Based on the real-time mass flow rate of nitrogen used for cold trap activation, determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be performed simultaneously, including: Calculate the maximum vaporization mass flow rate of nitrogen used for activation of the vaporization system; Based on the real-time mass flow rates of nitrogen used for activating the first-stage condensation filter, the second-stage condensation filter, and the cold trap, as well as the maximum vaporization mass flow rate, in the oil removal system for helium expansion refrigeration, determine whether to simultaneously activate the condensation filter and the cold trap.

[0012] Furthermore, Based on the initial activation duration of the first-stage coagulation filter in the oil removal system, the initial activation duration of the second-stage coagulation filter in the oil removal system, and the near-saturation time of the coagulation filter activation, the activation of the first-stage and second-stage coagulation filters is terminated, including: If the activation duration of the second-stage coagulation filter does not reach the initial activation duration, the second-stage coagulation filter will continue to be activated. Calculate the near-saturation activation time of the coagulation filter; The activation of the first-stage and second-stage coagulation filters is terminated based on the relative magnitudes of the initial activation duration of the first-stage coagulation filter in the oil removal system, the initial activation duration of the second-stage coagulation filter in the oil removal system, and the near-saturation activation time of the coagulation filters.

[0013] Secondly, based on the same inventive concept, this disclosure also provides a pre-discharge safety activation system for a helium expansion refrigeration hydrogen liquefaction station vaporization system. The system includes a first-stage condensation filter activation execution module, a second-stage condensation filter activation execution module, a cold trap activation execution module, and a first and second-stage condensation filter activation termination module. The first-stage condensate filter activation execution module is used to activate the first-stage condensate filter according to the real-time mass flow rate of nitrogen used for activation of the first-stage condensate filter in the oil removal system. The second-stage coagulation filter activation execution module is used to activate the second-stage coagulation filter according to the initial preparation activation duration of the first-stage coagulation filter in the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system. The cold trap activation execution module is used to determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be carried out simultaneously, based on the real-time mass flow rate of nitrogen used for cold trap activation. The activation termination module for the first and second stage coagulation filters is used to terminate the activation of the first and second stage coagulation filters based on the initial activation duration of the first stage coagulation filter in the oil removal system, the initial activation duration of the second stage coagulation filter in the oil removal system, and the near-saturation time of the coagulation filter activation.

[0014] Thirdly, based on the same inventive concept, this disclosure also provides an electronic device, including at least one processor and at least one memory electrically connected; The memory is electrically connected to the processor, wherein the memory stores instructions that can be executed by at least one of the processors to enable at least one of the processors to perform the pre-discharge safety activation method of the helium expansion refrigeration hydrogen liquefaction station vaporization system as described above.

[0015] Fourthly, based on the same inventive concept, this disclosure also provides a computer storage medium. The computer storage medium stores a computer program. When the computer program is executed by the processor, it implements the pre-discharge safety activation method for the helium expansion refrigeration hydrogen liquefaction station vaporization system as described above.

[0016] Fifthly, based on the same inventive concept, this disclosure also provides a computer program product. The computer program product is stored in at least one storage medium; The computer program product includes several instructions to cause at least one electronic device to perform the pre-discharge safety activation method for the helium expansion refrigeration hydrogen liquefaction station vaporization system as described above.

[0017] Compared with the prior art, this disclosure provides a safe activation method for the vaporization system of a helium expansion refrigeration hydrogen liquefaction station before liquid discharge, which has the following beneficial effects: During the activation of the two-stage condensation filter of the nitrogen-based oil removal system, the assessment and restriction of the "near-saturation" state of the nitrogen-based oil removal system's two-stage condensation filter activation during actual commissioning were considered. Based on this, the nitrogen demand for activation and the system's capacity to bear nitrogen activation during the simultaneous activation of the two-stage condensation filter and cold trap of the oil removal system were also assessed. This makes the safety assessment function of the hydrogen liquefaction station's vaporization system more comprehensive and complete, which can improve the safety assurance level of the hydrogen liquefaction system to a certain extent.

[0018] Other features and advantages of this disclosure will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the disclosure. The objects and other advantages of this disclosure may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic flowchart of a method for pre-discharge safety activation of a helium expansion refrigeration hydrogen liquefaction station vaporization system according to an embodiment of the present disclosure is shown. Figure 2 The relationship curve between the characteristic specific surface area and the ratio of specific surface area in the embodiments of this disclosure is shown; Figure 3 A graph showing the basic activation time of the first-stage coagulation filter element in an embodiment of this disclosure is provided. Figure 4 A graph of the thermal coupling coefficient in an embodiment of this disclosure is shown; Figure 5 A graph showing the concentration scaling factor of the second-stage coagulation filter element in an embodiment of this disclosure is shown; Figure 6 A graph showing the helium expansion specification ratio constant in an embodiment of this disclosure is provided. Figure 7 A graph showing the proportionality constant of the helium cycle pressure base inlet temperature in an embodiment of this disclosure is provided. Figure 8 A graph showing the influence coefficient of a specific specific heat in an embodiment of this disclosure is provided. Figure 9 A graph of the basic index of saturation effect in an embodiment of this disclosure is shown; Figure 10 A graph showing the transition adjustment coefficient of the saturation effect in an embodiment of this disclosure is provided. Figure 11 A graph showing the basic activation time of the second-stage coagulation filter element in an embodiment of this disclosure is provided. Figure 12 A schematic diagram illustrating the structural principle of an electronic device according to an embodiment of this disclosure is shown. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0022] For hydrogen liquefaction stations using helium expansion refrigeration, the vaporization of liquid nitrogen within the station plays a certain role before the hydrogen liquefaction system is officially put into operation. The vaporized nitrogen is used as a condensation filter in the oil removal system of the helium expansion refrigeration system and as an activation gas for the cold trap.

[0023] The condensation filters used in the helium oil removal system for expansion refrigeration, as well as the nitrogen used for activating the cold traps, are generally obtained by vaporizing liquid nitrogen stored on-site. If the helium oil removal system is not fully activated, oxygen carrying small amounts of moisture may be trapped in the condensation filters and cold traps at each stage. Directly introducing pressurized helium in this case may result in oxygen contamination of the pressurized helium, leading to substandard helium quality and wasted helium, which is highly uneconomical.

[0024] For helium-cooled hydrogen liquefaction stations, the helium used for refrigeration, after being pressurized, needs to pass through an oil removal system before being sent to the hydrogen liquefaction cold box for expansion and cooling. A typical helium oil removal system consists of two stages of condensation filters. The first stage is a pre-oil removal condensation filter, using a glass fiber condensation filter element; the second stage is a fine oil removal condensation filter, using a non-migratory ultra-high efficiency coalescing filter element. Before the oil removal system is put into operation, it needs to be activated with nitrogen. Considering the compact site requirements of some hydrogen liquefaction projects, the activation nitrogen for the oil removal system is obtained by vaporizing liquid nitrogen stored on-site. The two key factors for the activation nitrogen in the oil removal system are the circulating mass flow rate of cryogenic nitrogen and the purging maintenance time, ensuring that the filter elements of the two-stage condensation filters in the oil removal system meet the design performance requirements.

[0025] For glass fiber filter elements used in primary oil removal condensation filters, the calculation of the mass flow rate of activating nitrogen must be related to the initial oil content of the helium working fluid at the inlet of the helium oil removal system and the target oil content at the outlet of the first-stage condensation filter. This must be combined with structural parameters such as the specific surface area and porosity of the glass fiber condensation filter element to ensure that the purging capacity matches the oil load. The holding time of the activating nitrogen for the glass fiber condensation filter element needs to be related to the real-time temperature of the liquid nitrogen vaporization in the helium expansion refrigeration hydrogen liquefaction system and the expected target oil content of the helium working fluid at the outlet of the first-stage condensation filter.

[0026] For the non-migration ultra-high efficiency coalescing filter element used in the oil removal and coalescence filter, the calculation of the mass flow rate of the activating nitrogen must be related to the target oil content at the outlet of the first-stage coalescence filter (which is also the initial oil content at the inlet of the second-stage coalescence filter) and the target oil content at the outlet of the second-stage coalescence filter. This must be combined with heat transfer factors such as the heat capacity of the non-migration ultra-high efficiency coalescing filter element and the refining condensation rate to ensure that the purging capacity matches the oil load. The holding time of the activating nitrogen for the non-migration ultra-high efficiency coalescing filter element needs to be related to the real-time temperature of the liquid nitrogen after vaporization in the helium expansion refrigeration hydrogen liquefaction system and the expected target oil content index of the helium working fluid at the outlet of the second-stage coalescence filter.

[0027] For cold traps, activation with cryogenic nitrogen is necessary before the hydrogen liquefaction system is put into operation. The activation process requires determining the mass flow rate and duration of the cryogenic nitrogen. The mass flow rate of the nitrogen used for activation depends on the inlet temperature of the nitrogen, the initial temperature of the cold trap, and the cold trap's own adsorption capacity. The inlet temperature of the nitrogen and the initial temperature of the cold trap directly determine its enthalpy (cooling capacity per unit mass). The lower the inlet temperature of the nitrogen, the greater the thermodynamic temperature difference between the nitrogen and the initial state of the cold trap, and the stronger the heat transfer driving force. Therefore, the mass flow rate required to achieve the predetermined cooling rate can be reduced accordingly. The adsorption capacity of a cold trap is a macroscopic reflection of its internal structural complexity, adsorbent content, and heat capacity. A cold trap with a high adsorption capacity requires more total heat to be removed. Sufficient mass flow rate of cryogenic nitrogen must be applied to inject enough cooling capacity per unit time, preventing any working gas or impurities from pre-condensing on the cryogenic surface, thus ensuring that the cold trap achieves its designed optimal adsorption performance in subsequent operations.

[0028] Before the cryogenic system is officially put into operation, the calculation of the holding time for cryogenic nitrogen activation treatment of the cold trap is related to the ratio of the rated processing helium flow rate to the liquid hydrogen production flow rate and the target activation temperature. The ratio of the rated processing helium flow rate to the liquid hydrogen production flow rate substantially determines the potential load intensity faced by the cold trap. The higher the ratio, the greater the total amount of helium flowing through the cold trap per unit time, and the higher the absolute amount of trace impurities it carries. The target activation temperature of the cold trap is the fundamental basis for determining the thermodynamic time required for its body temperature drop process. Lower activation temperatures require longer cryogenic nitrogen holding times to ensure that the adsorbent and overall structure inside the cold trap uniformly and thoroughly reach the predetermined cryogenic state.

[0029] In embodiments of this disclosure, conventional valves can be used to control the gas.

[0030] Figure 1 A schematic flowchart of a safety activation method before liquid discharge for a helium expansion refrigeration hydrogen liquefaction station vaporization system according to an embodiment of the present disclosure is shown, as follows: Figure 1As shown in this embodiment, a method for pre-discharge safety activation of a helium expansion refrigeration hydrogen liquefaction station vaporization system includes the following steps: S1, based on the real-time mass flow rate of nitrogen used for activating the first-stage coagulation filter of the oil removal system, activate the first-stage coagulation filter.

[0031] (1) Start the vaporization of the liquid nitrogen stored in the vaporization station and monitor the real-time mass flow rate of nitrogen used for activation of the first-stage condensation filter of the oil removal system. .

[0032] Minimum mass flow rate threshold for nitrogen used in the activation of the first-stage condensation filter in the oil removal system: , In the above formula, A SSF1 The specific surface area (m²) of the glass fiber condensing filter element in the first-stage condensing filter of the helium oil removal system. 2 / g); P SSF1 Porosity (%) of the glass fiber condensation filter element in the first stage condensation filter of the helium oil removal system; The oil spill load flux is expressed as kg / (m²·s).

[0033] In the embodiments of this disclosure, the oil sludge load flux = , In the above formula, Q HECF (g / s) is the circulating mass flow rate of helium, C I1 (ppm) represents the initial oil content of the helium working medium at the inlet of the helium oil removal system.

[0034] k 1 is the reference activation coefficient of the glass fiber condensation filter element of the first-stage condensation filter, which is obtained by combining activation tests of various specifications of hydrogen liquefaction system equipment, and the unit is g / s; k 2 is the load-flow response index, which characterizes the sensitivity of the required purging mass flow rate of the glass fiber condensing filter element in the first stage of the helium oil removal system to changes in the total oil load. It is dimensionless. k 3 represents the relative weight of filter element impedance, which reflects the influence of the specific surface area of ​​the glass fiber condensing filter element in the first-stage condensing filter of the helium oil removal system on the difficulty of purging. It is dimensionless. k 4 is the filter element structural impedance index, which quantifies the amplification of the comprehensive impedance effect generated by the filter element's micro-geometry on airflow purging, and is dimensionless; k 5 represents the characteristic specific surface area of ​​the glass fiber condensing filter element in the first-stage condensing filter of the helium oil removal system, measured in m². 2 .

[0035] In one feasible embodiment: k 1 = 360; k The value of 2 is divided into segments. when When the value is in the range [0.001, 0.01], k 2 = 5.276 when When the value is in the range [0.01, 0.18], k 2 = 1.962, when When the value is in the range [0.18, 0.2], k 2=1, when When the value is in the range [0.2, 0.205], k 2 = 0.422, No hydrogen liquefaction system has been found so far. >0.205; k 3 = 8.321; k 4 = 0.261; The value of P HECF (MPa) is related, and the relationship between the two is as follows: Figure 2 As shown in the figure. Here, PHECF is the cyclic operating pressure of helium.

[0036] (2) Determine the operation of the first-stage coagulation filter based on the real-time mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system and the minimum threshold mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system.

[0037] If the real-time mass flow rate of nitrogen used for activation of the first-stage condensate filter in the helium-based oil removal system for expansion refrigeration is... The minimum activation threshold flow rate of the first-stage coagulation filter in the oil removal system is greater than or equal to that of the system. (g / s, grams per second), then the real-time mass flow rate of nitrogen used for activating the first-stage condensation filter can meet the minimum purging requirements of the oil load, and low-temperature nitrogen is used to purge and activate the first-stage condensation filter.

[0038] If the real-time mass flow rate of nitrogen used for activation of the first-stage condensate filter in the helium-based oil removal system for expansion refrigeration is... The flow rate is less than the minimum activation threshold of the first-stage condensation filter in the oil removal system. If the value is (g / s, grams per second), then the oil removal system will be shut down.

[0039] S2, based on the initial activation duration of the first-stage coagulation filter of the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter of the oil removal system, activate the second-stage coagulation filter.

[0040] (1) If the activation duration does not reach the initial preparation activation duration, the first-stage coagulation filter is activated continuously until the initial preparation activation duration of the first-stage coagulation filter is reached.

[0041] Initial activation duration of the first-stage condensate filter in the oil removal system (h): C O1 + , In the above formula, T LTR (K) represents the real-time temperature of liquid nitrogen vaporization within a helium expansion-cooled hydrogen liquefaction system; C O1 (ppm) represents the target oil content of the helium working fluid at the outlet of the first-stage condensation filter in the helium oil removal system.

[0042] λ 1 is the reference maintenance time coefficient, obtained from activation tests of various specifications of hydrogen liquefaction system equipment, and the unit is h; λ 2 is the duration-temperature response index, which characterizes the sensitivity of the required purging duration of the glass fiber condensation filter element of the first-stage condensation filter in the helium oil removal system to changes in the temperature range of the purging nitrogen. It is a single, dimensionless index. λ3 is the basic activation time of the filter element of the first-stage condensation filter in the helium oil removal system, in hours.

[0043] λ1=105; The values ​​of λ2 are segmented. when When the value of is in the range [0.001, 0.01], λ2 = 6. when When the value of λ is in the range [0.01, 0.18], λ2 = 15. when When the value of λ is in the range [0.18, 0.2], λ2 = 19. when When the value of λ is in the range [0.2, 0.205], λ2 = 21. No hydrogen liquefaction system has been found so far. >0.205; The value of λ3 is the ratio of the target oil content to the initial oil content of the helium working fluid at the outlet of the first-stage condensation filter in the helium oil removal system. (10) -2 The relationship between the two is as follows: Figure 3 As shown.

[0044] (2) Based on the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system. Activation of the second-stage coagulation filter is performed.

[0045] Minimum activation threshold flow rate of the second-stage condensation filter in the oil removal system : , In the above formula, TV SSF2 The refining condensation rate (K / min) of the non-migration ultra-high efficiency coalescing filter element in the second stage condensation filter of the helium oil removal system, SP SSF2 The specific heat capacity (m³) of the migration-free ultra-high efficiency coalescing filter element for the second-stage condensation filter of the helium oil removal system. 2 / g), C O2 The target oil content (ppm) of the helium working fluid at the outlet of the second-stage condensation filter of the helium oil removal system.

[0046] ζ1 is the reference activation coefficient for the migration-free ultra-high efficiency coalescing filter element of the second-stage coalescing filter, obtained from activation tests of various specifications of hydrogen liquefaction system equipment, with units of g / s; ζ2 is the thermal capacity coupling coefficient, which quantifies the linear contribution of the filter element's thermal capacity to the activation flow rate, and is dimensionless; ζ3 is the thermal inertia nonlinearity index, which describes the nonlinear characteristics of the filter element's thermal capacity's influence on the activation flow rate, and is dimensionless; ζ4 is the concentration scaling coefficient, which reflects the difficulty of scaling purity and can characterize the response curve of different stringent purity targets, and is dimensionless; ζ5 is the concentration offset, which reflects that even for a brand-new migration-free ultra-high efficiency coalescing filter element of the second-stage coalescing filter element of a helium oil removal system, its outlet concentration cannot truly reach absolute 0. ζ5 introduces a small offset, representing the background concentration limit that the migration-free ultra-high efficiency coalescing filter element of the second-stage coalescing filter element of a helium oil removal system can achieve.

[0047] ζ1=68; The value of ζ2 is related to the real-time temperature T after liquid nitrogen vaporization in the helium expansion refrigeration hydrogen liquefaction system. LTR (K) is related, and the relationship between the two is as follows: Figure 4 As shown; The value of ζ3 is segmented. when When the value of ζ is in the range [0.001, 0.01], ζ3 = 1. when When the value of ζ is in the range [0.01, 0.18], ζ3 = 0.663. when When the value of ζ is in the range [0.18, 0.2], ζ3 = 0.515. when When the value of ζ is in the range [0.2, 0.205], ζ3 = 0.402. No hydrogen liquefaction system has been found so far. >0.205; The value of ζ4 is the ratio of the target oil content to the initial oil content of the helium working fluid at the outlet of the second-stage condensation filter in the helium oil removal system. (10) -2 The relationship between the two is as follows: Figure 5 As shown; ζ5 = 0.025, the unit is ppm.

[0048] The activation triggering critical ratio P of the second-stage coagulation filter AAT The ratio of the target oil content of the helium working fluid at the outlet of the second-stage condensation filter to the target oil content of the helium working fluid at the outlet of the first-stage condensation filter. related, P AAT The values ​​are segmented and dimensionless: when The value is in

[10] -4 2.25×10 -3 At that time, P AAT =33%, when The value of is in the range [2.25×10]. -3 1.28×10 -3 At that time, P AAT =20%, when The value of is in the range of [1.28×10]. -3 When P is 0.01, AAT =15%, when When P is ≥0.01, AAT =12%.

[0049] For example, the real-time mass flow rate R of nitrogen used for activation in the second-stage condensation filter of an oil removal system for expansion refrigeration using helium. RTA2 The minimum activation threshold flow rate R of the second-stage condensate filter in the oil removal system is greater than or equal to the threshold flow rate. MTA2 If the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter is (g / s), then the minimum purging requirements of the oil load can be met.

[0050] If the real-time mass flow rate of nitrogen used for activating the second-stage coagulation filter of the oil removal system does not meet the minimum purging requirement of the oil load, the activation of the second-stage coagulation filter will not be started.

[0051] A control valve is installed between the first-stage condensate filter and the second-stage condensate filter. The second-stage condensate filter can only be activated after the control valve is opened.

[0052] S3. Based on the real-time mass flow rate of nitrogen used for cold trap activation, determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be carried out simultaneously.

[0053] S31, calculate the maximum vaporization mass flow rate of nitrogen used for activation of the vaporization system.

[0054] During actual commissioning, the cold trap of the helium-cooled hydrogen liquefaction station also needs to be activated with nitrogen. The duration of nitrogen activation for the cold trap may also be relatively long. If the activation of the condensation filter and the activation of the cold trap need to be carried out simultaneously, it is necessary to determine whether the nitrogen used for simultaneous activation exceeds the nitrogen activation capacity of the vaporization system, i.e., the maximum vaporization mass flow rate of nitrogen used for activation in the vaporization system. .

[0055] , In the above formula, (g / s) represents the rated liquid hydrogen production capacity of a helium expansion refrigeration hydrogen liquefaction system; (K, Kelvin temperature) is the inlet temperature of nitrogen used for cold trap activation after vaporization of liquid nitrogen in a helium expansion refrigeration hydrogen liquefaction system. (m) 3 (cubic meters) is the real-time liquid nitrogen volume in the liquid nitrogen storage tank of a hydrogen liquefaction system with helium expansion refrigeration.

[0056] 1 is a helium expansion specification proportionality constant, determined by experiments on hydrogen liquefaction systems with different helium specifications for expansion, and is dimensionless; 2 is the saturation temperature (reference temperature) of liquid nitrogen, in K. 3 is the helium cycle pressure-based inlet temperature proportionality constant, used to characterize the nonlinearity of the effect of the inlet temperature of nitrogen for cold trap activation on the flow rate, and is dimensionless; 4 is the reference liquid nitrogen volume, in cubic meters (m³). 3 .

[0057] The value of 1 and the circulating mass flow rate of helium (g / s) is related, and the relationship between the two is as follows: Figure 6 As shown; 2 = 77; The value of 3 and the working pressure of helium cycling (MPa, megapascal) is related to the two, and their relationship is as follows: Figure 7 As shown; 4 = 650.

[0058] S32, based on the real-time mass flow rate of nitrogen used for activation of the first-stage condensate filter in the helium-based oil removal system for expansion refrigeration. Real-time mass flow rate of nitrogen used for activation of the second-stage condensation filter Real-time mass flow rate of nitrogen for cold trap activation Maximum vaporization mass flow rate Determine whether to activate the condensation filter and the cold trap simultaneously.

[0059] Real-time mass flow rate of nitrogen used for activation of the first-stage condensation filter Real-time mass flow rate of nitrogen used for activation of the second-stage condensation filter Real-time mass flow rate of nitrogen for cold trap activation These three variables are monitored in real time using measuring instruments.

[0060] (1) If none of the three variables exceed the maximum vaporization mass flow rate, and the activation nitrogen used by the first and second stage condensation filters and the cold trap does not exceed the system's nitrogen activation capacity, then it is determined that the activation of the condensation filter and the activation of the cold trap can be carried out simultaneously.

[0061] .

[0062] (1.1) Based on the real-time mass flow rate R of nitrogen used for cold trap activation RCDA (kg / s), to perform activation of the cold trap.

[0063] Minimum activation threshold flow rate of cold trap : , In the above formula, C CHA The adsorption capacity of the cold trap (Pa·m) 3 / K);T CHI T represents the initial temperature (K) of the cold trap. LTR The inlet temperature (K) of the nitrogen used for activation of the cold trap after vaporization of liquid nitrogen in the hydrogen liquefaction system for helium expansion cooling.

[0064] 1 is the comprehensive proportionality coefficient, which is dimensionless; 2 is the adsorption capacity influence coefficient, which reflects the nonlinear influence of the cold trap heat load on the flow rate demand and is dimensionless; 3 represents the calibrated specific heat capacity, with units of kJ / (kg). K); 4 is the special specific heat influence coefficient, which describes the adjustment coefficient of special heat transfer changes under low temperature nitrogen atmosphere, and the unit is K; 5 units represent kJ / (kg) K); 6 units represent kJ / (kg) K); 7. Dimensionless, used in combination to approximate the relationship between the specific heat capacity of nitrogen at low temperatures and temperature.

[0065] The value of 1 is segmented. When T LTRWhen the value is in the range [76K, 95K], 1=1, When T LTR When the value is in [95K, 120K], 1 = 1.576 When T LTR At ≥120K, 1 = 1.667; The value of 2 and R LHP related, When R LHP When the value is in the range of [1.16 g / s, 20.83 g / s], 2=1, When R LHP When the value is in the range of [20.83 g / s, 52.08 g / s], 2 = 0.242, When R LHP When the value is in the range of [52.08 g / s, 115.74 g / s], 2 = 0.009; 3 = 2.18; The value of 4 is related to the difference between the initial temperature of the cold trap and the inlet temperature of the nitrogen used for cold trap activation after vaporization of liquid nitrogen in the helium expansion cooling hydrogen liquefaction system. Related, relationship, such as Figure 8 As shown; 5 = 1.048; 6 = -0.00127; 7 = 2.46.

[0066] If the real-time mass flow rate R of nitrogen used for cold trap activation RCDA (kg / s) ≥ or greater than the minimum activation threshold flow rate R of the cold trap CDA If the mass flow rate of nitrogen used for activation of the first-stage coagulation filter is (kg / s), then the mass flow rate of nitrogen can meet the minimum purging requirements of the oil load; if it is not met, the cold trap will be shut down.

[0067] (1.2) Maintain the activation time of the cold trap until the cold trap preparation activation duration T. CDA (h): , In the above formula, R HER (g / s) is the rated helium flow rate of the cold trap, R LHP (g / s) is the rated liquid hydrogen production capacity of a helium expansion refrigeration hydrogen liquefaction system, TCHI (K) is the initial temperature of the cold trap, T CHTA (K) is the target activation temperature of the cold trap.

[0068] 1 represents the baseline activation time under reference conditions, which is the actual measured value in hours. 2 is the standardized load ratio, used for dimensionless calculation. Dimensionless; 3. The combination of 4 is used to describe the load ratio. The saturation effect on the activation duration of the cold trap, among which 3 is the basic index of saturation effect, representing the dimensionless growth rate in the low-load region. 4 is the saturation effect auxiliary regulation index, which is dimensionless; 5 is the saturation effect transition adjustment coefficient, which characterizes the transition adjustment from the low load region maintained by the activation of the cold trap to the high load region, and is dimensionless; 6 is the critical adjustment coefficient for the saturation effect, which represents the critical load value (center point) of the transition zone for maintaining the activation of the cold trap. It is dimensionless.

[0069] 1 = 106; 2 = 0.2642; 3 and the adsorption capacity C of the cold trap CHA (Pa·m) 3 / K) related, such as Figure 9 As shown; 4 = 0.0966; 5. The difference between the target activation temperature of the cold trap and the real-time temperature after liquid nitrogen vaporization in the helium expansion-cooled hydrogen liquefaction system (T) CHTA -T LTR (K) related, such as Figure 10 As shown; 6 = 0.0261.

[0070] When the actual activation time of the cold trap reaches the cold trap preparation activation duration t CDA Subsequently, it was determined that the vaporization of the liquid nitrogen used for activating the cold trap had safely ended.

[0071] When the actual activation time of the cold trap does not reach the cold trap preparation activation duration t CDA This means that the vaporization of liquid nitrogen used for activating the cold trap needs to be continuously promoted.

[0072] (2) If at least one of the three variables exceeds the maximum vaporization mass flow rate, the condensation filter activation and cold trap activation cannot be started simultaneously.

[0073] You can choose to activate the first and second stage condensation filters of the oil removal system first, or you can choose to activate the cold trap first.

[0074] S4. Based on the initial activation duration of the first-stage coagulation filter of the oil removal system, the initial activation duration of the second-stage coagulation filter of the oil removal system, and the near-saturation time of the coagulation filter activation, the activation of the first-stage coagulation filter and the second-stage coagulation filter is terminated.

[0075] (1) If the activation duration of the second-stage coagulation filter does not reach the initial activation duration, the second-stage coagulation filter will continue to be activated.

[0076] Initial activation duration of the second-stage condensate filter in the oil removal system (h): C O2 + , In the above formula, T LTR (K) represents the real-time temperature of liquid nitrogen vaporization within a helium expansion-cooled hydrogen liquefaction system; C O2 (ppm) represents the target oil content of the helium working fluid at the outlet of the second-stage condensation filter in the helium oil removal system.

[0077] 1 is the reference maintenance time coefficient, obtained from activation tests of various specifications of hydrogen liquefaction system equipment, and the unit is h; 2 represents the duration-temperature response index, which characterizes the sensitivity of the purging duration required for the migration-free ultra-high efficiency coalescing filter element of the second-stage coalescing filter in the helium oil removal system to changes in the temperature range of the purging nitrogen. It is dimensionless. 3 represents the basic activation time of the second-stage condensation filter element in the helium oil removal system, measured in hours (h).

[0078] 1 = 198; The value of 2 is divided into segments. when When the value is in the range [0.001, 0.01], 2 = 0.75 when When the value is in the range [0.01, 0.18], 2 = 0.85, when When the value is in the range [0.18, 0.2], 2 = 1.15 when When the value is in the range [0.2, 0.205], 2 = 1.4, No hydrogen liquefaction system has been found so far. >0.205; The value of 3 is the ratio of the target oil content of the helium working fluid at the outlet of the second-stage condensation filter in the helium oil removal system to the initial oil content of the first-stage condensation filter. (10) -4 The relationship between the two is as follows: Figure 11 As shown.

[0079] (2) Calculate the activation near-saturation time of the coagulation filter.

[0080] For the helium oil removal system of the helium-cooled hydrogen liquefaction station, nitrogen activation is required. The nitrogen activation time needs to be relatively long, but after a certain period of time, no matter how much the nitrogen activation time is extended, the improvement of the activation effect will be very limited.

[0081] The embodiments of this disclosure use an activation near-saturation time T ANS This is used to characterize this phenomenon.

[0082] Activation near saturation time T ANS The value of and the maximum temperature difference within 24 hours in the environment of the hydrogen liquefaction system with helium expansion refrigeration. and the maximum rate of temperature change in the environment within 24 hours. These three variables are related: , In the above formula, T MD (K) represents the maximum temperature difference in the environment of the helium expansion refrigeration hydrogen liquefaction system within 24 hours; R MTC (10) -2 K / min represents the maximum rate of temperature change in the environment over 24 hours.

[0083] 1 is the reference activation near-saturation coefficient, obtained from activation tests of various specifications of hydrogen liquefaction system equipment, and the unit is h; 2 is the maximum temperature difference resistance index, which quantifies the amplification effect of the maximum temperature difference in the environment of the hydrogen liquefaction system on the activation near saturation, and is dimensionless; 3 is the maximum temperature difference resistance index, which quantifies the amplification effect of the maximum temperature difference change in the environment of the hydrogen liquefaction system on the activation near saturation, and is dimensionless.

[0084] 1 = 768; The value of 2 is divided into segments. When R LHP When the value of k is in the range of [1.16 g / s, 20.83 g / s], k2 = 2.24 × 10 -4 , When R LHP When the value of k is in the range of [20.83 g / s, 52.08 g / s], k2 = 0.242 × 10 -3 , When R LHP When the value of k is in the range of [52.08 g / s, 115.74 g / s], k2 = 0.1048; The value of 3 is divided into segments. When T db When the value of k is in the range [0K, 4.8K], k2 = 3.09 × 10 -5 , When T db When the value of is in the range [4.8K, 9.6K], k2 = 1.86 × 10 -6 , When T db When the value of is in the range [9.6K, 10.8K], k2 = 1.13 × 10 -6 , When T db When the value of is in the range [10.8K, 11.2K], k2 = 0.92 × 10 -7 , When T db When the value of is in the range [11.2K, 16K], k2 = 0.78 × 10 -7 .

[0085] T db T represents the target boiling point subcooling (K) of the liquid hydrogen product to be output from a helium expansion refrigeration hydrogen liquefaction system; db It is the difference between the actual temperature of the produced liquid hydrogen product and the boiling point of liquid hydrogen, 21K. This value is generally between 0 and 16K.

[0086] (3) Determine whether to end based on the following: i) Such as activation near saturation time If the final activation duration of the first-stage coagulation filter is the maximum of the three, then the final activation duration of the second-stage coagulation filter is taken as the initial preparation activation duration T of the first-stage coagulation filter. MTA1 The initial activation duration T of the second-stage coagulation filter MTA2 The larger value is considered when the vaporization of liquid nitrogen used for activation is safely concluded.

[0087] ii) If activation is near saturation time If the value is the minimum of the three, then the final activation duration T of the first-stage coagulation filter is... MTA1 Second-stage coagulation filter T MTA2 The final activation duration reaches This means assessing that the vaporization of liquid nitrogen used for activation has safely ended.

[0088] iii) Activation time near saturation The second largest of the three, the initial activation duration T of the first-stage coagulation filter. MTA1 The maximum of the three, the initial activation duration T of the second-stage coagulation filter. MTA2 If the value is the minimum of the three, then the final activation duration of both the first-stage and second-stage coagulation filters is taken as... This means assessing that the vaporization of liquid nitrogen used for activation has safely ended.

[0089] iv) Such as activation near saturation time The second largest of the three, the initial activation duration T of the first-stage coagulation filter. MTA1 The minimum of the three, the initial activation duration T of the second-stage coagulation filter. MTA2 If the value is the maximum of the three, then the final activation duration of both the first-stage and second-stage coagulation filters is taken as... This means assessing that the vaporization of liquid nitrogen used for activation has safely ended.

[0090] Based on the same inventive concept as the above-disclosed method, this disclosure also provides a pre-discharge safety assessment system for a helium expansion refrigeration hydrogen liquefaction station vaporization system, including a first-stage condensation filter activation execution module, a second-stage condensation filter activation execution module, a cold trap activation execution module, and a first and second-stage condensation filter activation termination module. The first-stage condensate filter activation execution module is used to activate the first-stage condensate filter according to the real-time mass flow rate of nitrogen used for activation of the first-stage condensate filter in the oil removal system. The second-stage coagulation filter activation execution module is used to activate the second-stage coagulation filter according to the initial preparation activation duration of the first-stage coagulation filter in the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system. The cold trap activation execution module is used to determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be carried out simultaneously, based on the real-time mass flow rate of nitrogen used for cold trap activation. The activation termination module for the first and second stage coagulation filters is used to terminate the activation of the first and second stage coagulation filters based on the initial activation duration of the first stage coagulation filter in the oil removal system, the initial activation duration of the second stage coagulation filter in the oil removal system, and the near-saturation time of the coagulation filter activation.

[0091] Based on the same inventive concept as the above-disclosed content, this disclosure also provides an electronic device. For example... Figure 12 As shown, the electronic device of this disclosure embodiment includes at least one processor and at least one memory electrically connected to the processor. The memory is electrically connected to the processor, wherein the memory stores instructions executable by the at least one processor. The instructions are executed by the at least one processor to enable the at least one processor to perform the pre-discharge safety assessment method for the helium expansion refrigeration hydrogen liquefaction station vaporization system as described above.

[0092] It should be noted that the electrical connection between the above-mentioned units does not necessarily mean the connection between lines. The indirect connection method can be applied to the embodiments of this disclosure as long as it achieves the purpose of this disclosure.

[0093] Based on the same inventive concept, this disclosure also provides a computer storage medium storing a computer program, which, when executed by a processor, implements the pre-discharge safety assessment method for the helium expansion refrigeration hydrogen liquefaction station vaporization system as described above.

[0094] Based on the same inventive concept, this disclosure also provides a computer program product stored in at least one storage medium; the computer program product includes several instructions to cause at least one computer device to execute the pre-discharge safety assessment method for the helium expansion refrigeration hydrogen liquefaction station vaporization system as described above.

[0095] Although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A method for safe activation of a helium expansion refrigeration hydrogen liquefaction station vaporization system before liquid discharge, characterized in that, The method includes, The activation of the first-stage coagulation filter is performed based on the real-time mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system. The activation of the second-stage coagulation filter is performed based on the initial activation duration of the first-stage coagulation filter in the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system. Based on the real-time mass flow rate of nitrogen used for cold trap activation, determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be carried out simultaneously. Based on the initial activation duration of the first-stage coagulation filter in the oil removal system, the initial activation duration of the second-stage coagulation filter in the oil removal system, and the near-saturation time of the coagulation filter activation, the activation of the first-stage and second-stage coagulation filters is terminated.

2. The method for safe activation before liquid discharge of the helium expansion refrigeration hydrogen liquefaction station vaporization system according to claim 1, characterized in that, Based on the real-time mass flow rate of nitrogen used for activating the first-stage condensate filter in the oil removal system, activation of the first-stage condensate filter is performed, including: Start the vaporization of liquid nitrogen stored in the vaporization station and monitor the real-time mass flow rate of nitrogen used for activation of the first-stage condensation filter in the oil removal system; The operation of the first-stage coagulation filter is determined based on the real-time mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system and the minimum threshold mass flow rate of nitrogen used for activation of the first-stage coagulation filter in the oil removal system.

3. The method for safe activation before liquid discharge of the helium expansion refrigeration hydrogen liquefaction station vaporization system according to claim 1, characterized in that, Based on the initial activation duration of the first-stage coagulation filter in the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system, activation of the second-stage coagulation filter is performed, including: If the activation duration does not reach the initial preparation activation duration, the first-stage coagulation filter will continue to be activated until the initial preparation activation duration of the first-stage coagulation filter is reached. The activation of the second-stage condensate filter is performed based on the real-time mass flow rate of nitrogen used for activation of the second-stage condensate filter in the oil removal system.

4. The method for safe activation before liquid discharge of the helium expansion refrigeration hydrogen liquefaction station vaporization system according to claim 3, characterized in that, A control valve is installed between the first-stage condensate filter and the second-stage condensate filter. The second-stage condensate filter can only be activated after the control valve is opened.

5. The method for safe activation before liquid discharge of the helium expansion refrigeration hydrogen liquefaction station vaporization system according to claim 1, characterized in that, Based on the real-time mass flow rate of nitrogen used for cold trap activation, determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be performed simultaneously, including: Calculate the maximum vaporization mass flow rate of nitrogen used for activation of the vaporization system; Based on the real-time mass flow rates of nitrogen used for activating the first-stage condensation filter, the second-stage condensation filter, and the cold trap, as well as the maximum vaporization mass flow rate, in the oil removal system for helium expansion refrigeration, determine whether to simultaneously activate the condensation filter and the cold trap.

6. The method for safe activation before liquid discharge of the helium expansion refrigeration hydrogen liquefaction station vaporization system according to claim 1, characterized in that, Based on the initial activation duration of the first-stage coagulation filter in the oil removal system, the initial activation duration of the second-stage coagulation filter in the oil removal system, and the near-saturation time of the coagulation filter activation, the activation of the first-stage and second-stage coagulation filters is terminated, including: If the activation duration of the second-stage coagulation filter does not reach the initial activation duration, the second-stage coagulation filter will continue to be activated. Calculate the near-saturation activation time of the coagulation filter; The activation of the first-stage and second-stage coagulation filters is terminated based on the relative magnitudes of the initial activation duration of the first-stage coagulation filter in the oil removal system, the initial activation duration of the second-stage coagulation filter in the oil removal system, and the near-saturation activation time of the coagulation filters.

7. A safety activation system before liquid discharge for a helium expansion refrigeration hydrogen liquefaction station vaporization system, characterized in that, The system includes a first-stage condensation filter activation execution module, a second-stage condensation filter activation execution module, a cold trap activation execution module, and a first and second-stage condensation filter activation termination module. The first-stage condensate filter activation execution module is used to activate the first-stage condensate filter according to the real-time mass flow rate of nitrogen used for activation of the first-stage condensate filter in the oil removal system. The second-stage coagulation filter activation execution module is used to activate the second-stage coagulation filter according to the initial preparation activation duration of the first-stage coagulation filter in the oil removal system and the real-time mass flow rate of nitrogen used for activation of the second-stage coagulation filter in the oil removal system. The cold trap activation execution module is used to determine whether the activation of the first and second stage condensation filters of the oil removal system and the activation of the cold trap can be carried out simultaneously, based on the real-time mass flow rate of nitrogen used for cold trap activation. The activation termination module for the first and second stage coagulation filters is used to terminate the activation of the first and second stage coagulation filters based on the initial activation duration of the first stage coagulation filter in the oil removal system, the initial activation duration of the second stage coagulation filter in the oil removal system, and the near-saturation time of the coagulation filter activation.

8. An electronic device, characterized in that, Includes at least one processor and at least one memory electrically connected; The memory is electrically connected to the processor, wherein the memory stores instructions executable by at least one of the processors, the instructions being executed by at least one of the processors to enable at least one of the processors to perform the pre-discharge safety activation method for the helium expansion refrigeration hydrogen liquefaction station vaporization system as described in any one of claims 1-6.

9. A computer storage medium, characterized in that, The computer storage medium stores a computer program. When the computer program is executed by the processor, it implements the pre-discharge safety activation method for the helium expansion refrigeration hydrogen liquefaction station vaporization system according to any one of claims 1-6.

10. A computer program product, characterized in that, The computer program product is stored in at least one storage medium; The computer program product includes several instructions to cause at least one electronic device to execute the pre-discharge safety activation method for the helium expansion refrigeration hydrogen liquefaction station vaporization system according to any one of claims 1-6.

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