Pulse ammonia removal method

Abstract

The invention provides a pulse ammonia removal method which is suitable for a hydrogen purifier, a membrane electrode is arranged in the hydrogen purifier, the membrane electrode comprises a catalyst layer and a proton exchange membrane and is used for removing ammonia located on the catalyst layer and the proton exchange membrane, and the ammonia removal method comprises the following steps: when the hydrogen purifier is under a set condition, the membrane electrode is used for removing ammonia on the catalyst layer and the proton exchange membrane; introducing mixed gas in a set proportion into the anode of the hydrogen purifier, and introducing hydrogen into the cathode of the hydrogen purifier; pulse voltage is introduced into the hydrogen purifier for multiple times through the pulse power supply, so that the ammonia attached to the catalyst layer and the proton exchange membrane is subjected to oxidation reaction, and the ammonia is separated from the catalyst layer and the proton exchange membrane; wherein the mixed gas comprises hydrogen and ammonia gas, and the set condition is that the hydrogen purifier is at the set temperature, and the value range of the ratio of the hydrogen to the ammonia gas is (99-99.9): (1-0.1); the problems of catalyst poisoning and performance degradation caused by ammonia residues of an electrochemical hydrogen purifier in the prior art are solved.

Description

Technical Field

[0001] This application relates to the field of ammonia removal technology, and more specifically, to a pulse ammonia removal method. Background Technology

[0002] Hydrogen energy plays a crucial role in reducing dependence on fossil fuels and ensuring national energy security; however, hydrogen storage and transportation remain key challenges in its application. Ammonia, as a highly efficient hydrogen storage medium, can be transported in liquid form and then pyrolyzed to produce hydrogen, providing a viable pathway for hydrogen storage and transportation. Electrochemical hydrogen purification technology, utilizing a structure similar to proton exchange membrane fuel cells, separates and purifies hydrogen by oxidizing hydrogen at the anode through an electrochemical reaction. The protons are then transported across the membrane to the cathode and recombine to form hydrogen molecules. However, incompletely reacted ammonia impurities during ammonia pyrolysis can severely poison the catalyst and proton exchange membrane of the electrochemical hydrogen purifier, significantly impacting the equipment's separation efficiency and durability. Traditional solutions, such as disassembling and replacing critical components, are not only complex but also costly, limiting the commercial application of electrochemical purification technology. Summary of the Invention

[0003] The main objective of this invention is to provide a pulsed ammonia removal method to solve the problems of membrane electrode poisoning and performance degradation caused by ammonia residue in existing electrochemical hydrogen purifiers.

[0004] To achieve the above objectives, according to one aspect of the present invention, a pulsed ammonia removal method is provided. This pulsed ammonia removal method is applicable to a hydrogen purifier, which is equipped with a membrane electrode comprising a catalytic layer and a proton exchange membrane. The pulsed ammonia removal method is used to remove ammonia located on the catalytic layer and the proton exchange membrane. The ammonia removal method includes:

[0005] When the hydrogen purifier is under set conditions, a set proportion of mixed gas is introduced into the anode of the hydrogen purifier, and hydrogen is introduced into the cathode of the hydrogen purifier.

[0006] A pulse voltage is applied to the hydrogen purifier by a pulse power supply to cause the ammonia gas attached to the catalyst layer and proton exchange membrane to undergo an oxidation reaction, thereby separating the ammonia gas from the catalyst layer and proton exchange membrane.

[0007] The mixed gas includes hydrogen and ammonia. The set conditions are that the hydrogen purifier is at a set temperature and the set ratio is that the ratio of hydrogen to ammonia is in the range of (99~99.9):(1~0.1).

[0008] Furthermore, prior to the step of applying a pulsed voltage to the hydrogen purifier via a pulsed power supply, the following steps are included:

[0009] Apply a standby voltage to the hydrogen purifier;

[0010] The waiting time for the cumulative waiting voltage;

[0011] When the waiting time reaches the first duration, a pulse voltage is applied to the hydrogen purifier.

[0012] Furthermore, the step of applying a pulsed voltage to the hydrogen purifier also includes:

[0013] The cumulative pulse duration after the applied pulse voltage;

[0014] When the pulse duration is the second duration, continue to supply the waiting voltage to the hydrogen purifier and repeat the step of accumulating the waiting voltage for the waiting duration until the supply of mixed gas to the hydrogen purifier stops.

[0015] Furthermore, the flow rate of the mixed gas applied to the hydrogen purifier is between 36.26 L / min and 37.74 L / min.

[0016] Furthermore, the flow rate of hydrogen introduced into the cathode of the hydrogen purifier is between 36.26 L / min and 37.74 L / min.

[0017] Furthermore, the waiting voltage is between 2.47V and 2.53V.

[0018] Furthermore, the waiting time ranged from 59.4s to 60.6s.

[0019] Furthermore, the pulse voltage is between 17.32V and 17.67V.

[0020] Furthermore, the pulse duration is between 14.85s and 15.15s.

[0021] Furthermore, the temperature is set between 79.2°C and 80.8°C.

[0022] By applying the technical solution of this invention, periodic pulsed voltages are applied to the electrochemical hydrogen purifier, effectively removing ammonia adsorbed on the catalyst layer and proton exchange membrane, thereby significantly improving the performance and service life of the hydrogen purifier. Traditional hydrogen purifiers are extremely sensitive to ammonia; even trace amounts of ammonia can poison the catalyst, severely affecting purification efficiency. With pulsed ammonia removal technology, the purifier can tolerate higher concentrations of ammonia, ensuring stable operation in the ammonia-containing tail gas environment generated by ammonia pyrolysis, and improving the overall reliability and flexibility of the system.

[0023] Periodic pulsed voltages induce a rapid oxidation reaction of ammonia, effectively removing ammonia adsorption on the catalyst layer and releasing ammonia-poisoned active sites. This not only restores the initial activity of the catalyst but also prevents permanent degradation of catalyst performance caused by prolonged ammonia adsorption, enhancing the long-term performance stability of the electrochemical hydrogen purifier.

[0024] Compared to traditional methods, pulse ammonia removal technology eliminates the need for frequent disassembly, cleaning, or replacement of critical components in the purifier. This significantly reduces maintenance workload and costs, while also minimizing downtime caused by equipment maintenance, thereby improving the economic efficiency and operational effectiveness of the hydrogen purification system. Attached Figure Description

[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0026] Figure 1 A schematic diagram of the connection structure of the electrochemical purifier and the pulse power supply according to an embodiment of this application is shown;

[0027] Figure 2 A schematic diagram of the electrochemical pulse technology according to an embodiment of this application is shown;

[0028] Figure 3 The diagram shows the change in operating current during the electrochemical pulse ammonia removal process according to an embodiment of this application. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] Hydrogen energy plays a crucial role in reducing dependence on fossil fuels and ensuring national energy security; however, hydrogen storage and transportation remain key challenges in its application. Ammonia, as a highly efficient hydrogen storage medium, can be transported in liquid form and then pyrolyzed to produce hydrogen, providing a viable pathway for hydrogen storage and transportation. Electrochemical hydrogen purification technology, utilizing a structure similar to proton exchange membrane fuel cells, separates and purifies hydrogen by oxidizing hydrogen at the anode through an electrochemical reaction. The protons are then transported across the membrane to the cathode and recombine to form hydrogen molecules. However, incompletely reacted ammonia impurities during ammonia pyrolysis can severely poison the catalyst and proton exchange membrane of the electrochemical hydrogen purifier, significantly impacting the equipment's separation efficiency and durability. Traditional solutions, such as disassembling and replacing critical components, are not only complex but also costly, limiting the commercial application of electrochemical purification technology.

[0031] The main objective of this invention is to provide a pulsed ammonia removal method to solve the problems of catalyst poisoning and performance degradation caused by ammonia residue in existing electrochemical hydrogen purifiers.

[0032] like Figures 1 to 3 As shown, the pulsed ammonia removal method provided in this application embodiment is applicable to a hydrogen purifier. The hydrogen purifier is equipped with a membrane electrode, which includes a catalytic layer and a proton exchange membrane. The pulsed ammonia removal method is used to remove ammonia gas located on the catalytic layer and the proton exchange membrane. The ammonia removal method includes:

[0033] When the hydrogen purifier is under set conditions, a set proportion of mixed gas is introduced into the anode of the hydrogen purifier, and hydrogen is introduced into the cathode of the hydrogen purifier.

[0034] A pulse voltage is applied to the hydrogen purifier by a pulse power supply to cause the ammonia gas attached to the catalyst layer and proton exchange membrane to undergo an oxidation reaction, thereby separating the ammonia gas from the catalyst layer and proton exchange membrane.

[0035] The mixed gas includes hydrogen and ammonia. The set conditions are that the hydrogen purifier is at a set temperature and the set ratio is that the ratio of hydrogen to ammonia is in the range of (99~99.9):(1~0.1).

[0036] Optionally, the hydrogen:ammonia ratio can be any one of 99:1, 99.1:0.9, 99.2:0.8, 99.3:0.7, 99.4:0.6, 99.5:0.5, 99.6:0.4, 99.7:0.3, 99.8:0.2, 99.9:0.1, etc., as long as the ammonia content is below 1%, and the total amount of ammonia and hydrogen is 100%.

[0037] Preferably, in this embodiment, the ratio of hydrogen to ammonia is 99:1.

[0038] Furthermore, before the step of applying a pulse voltage to the hydrogen purifier via a pulse power supply, the process includes: applying a waiting voltage to the hydrogen purifier, accumulating the waiting time of the waiting voltage, applying a pulse voltage to the hydrogen purifier when the waiting time reaches a first duration, applying a waiting voltage to the hydrogen purifier when the accumulated pulse duration reaches 15 seconds after applying the pulse voltage, continuing to apply the waiting voltage to the hydrogen purifier, accumulating the waiting time of the waiting voltage again, applying a pulse voltage to the hydrogen purifier when the waiting time reaches 60 seconds, and repeating the above steps.

[0039] During electrochemical pulse operation, due to the effect of the pulse potential, the anodic potential will instantaneously rise to a sufficiently positive value and remain at that potential value for a period of time (e.g., Figure 2This increase in positive potential is crucial for accelerating the ammonia oxidation reaction, allowing ammonia to be rapidly oxidized at the anode. However, this process also involves an increase in the electrochemical purifier potential, which may even approach the power supply protection threshold. The duration of the high potential within a single pulse cycle is called the pulse time, and its length determines the thoroughness of ammonia removal. A longer pulse time ensures sufficient ammonia oxidation, but it may also increase energy consumption and potential system risks. It is worth noting that in addition to the small energy input required for the entire process, the triggering pulse device also requires additional energy input, resulting in significant energy loss during the pulse, at which point the electrochemical purifier operates with lower energy efficiency.

[0040] After the pulse duration ends, as ammonia oxidizes, the current in the electrochemical purifier gradually returns to levels close to those used when operating with pure hydrogen. Subsequently, ammonia begins to slowly re-adsorb onto the catalyst surface, causing the current in the electrochemical purifier to decrease again. The duration the purifier operates at low potential within a single pulse cycle is the waiting time, which is also the interval between two adjacent pulses. The length of the waiting time directly affects the amount of ammonia adsorbed on the catalyst surface. A shorter waiting time means less ammonia adsorbed on the catalyst surface, thus requiring a shorter pulse duration for effective removal. Conversely, a longer waiting time results in more active sites on the catalyst being occupied by ammonia, thus requiring a further extension of the pulse duration to ensure effective ammonia removal, which reduces the system's energy efficiency.

[0041] Therefore, to achieve optimal ammonia removal and electrochemical purifier performance, it is necessary to finely adjust and optimize the waiting time and pulse time based on the specific operating conditions and ammonia concentration levels of the electrochemical purifier in practical applications. These adjustments can significantly improve the average performance of the electrochemical purifier when processing ammonia-containing gases, enabling efficient operation of the electrochemical pulse technology and achieving the best performance of the electrochemical purifier system.

[0042] This invention utilizes electrochemical pulse ammonia removal technology to remove residual ammonia from the feed gas, thereby eliminating its impact on the membrane electrode of the electrochemical hydrogen purifier. The pulse signal in this scheme is generated using a dedicated pulse power supply. From the principle of electrochemical pulse ammonia removal, when a higher potential is applied to the anode of the purifier, driven by the potential difference between the anode and cathode, the ammonia in the mixed gas undergoes an electrochemical reaction and transforms into other products, thus solving the problem of ammonia's influence on the electrochemical purifier.

[0043] Considering the impact of ammonia poisoning on the membrane electrode and the complexity of disassembling the purifier, this process not only reduces efficiency but also increases maintenance costs. This invention, by combining electrochemical reactions with pulse technology, can efficiently and conveniently restore the efficiency and performance of a hydrogen purifier without disassembling it. The pulse ammonia removal method of this invention includes the following implementation steps:

[0044] Before performing the electrochemical pulse ammonia removal operation, ensure the electrochemical hydrogen purifier is at 80°C. Introduce a certain amount of mixed gas feedstock (at a flow rate of 37 L / min and a hydrogen to ammonia ratio of 99:1) to the anode of the purifier, and introduce a certain amount of hydrogen (30 L / min) to the cathode. At this time, the working voltage (waiting voltage) applied to the purifier by the pulse power supply is 2.5V, and the waiting time is 60 seconds. The working current of the purifier is as follows: Figure 3 As shown in section A. Due to the poisoning of the purifier by ammonia in the raw gas, the operating current after applying voltage is only 110A, which is only about 50% of the theoretical value (210A).

[0045] During electrochemical pulse operation, with a constant gas flux (37 L / min), the voltage applied by the pulse power supply was increased to 17.5 V for a pulse duration of 15 seconds. This higher potential accelerated the ammonia oxidation reaction at the anode. During the pulse duration, the purifier's operating current also rapidly increased to a higher value, such as... Figure 3 As shown in section B.

[0046] After the pulse duration ended, the applied voltage of the pulse power supply decreased to the original waiting voltage of 2.5V, with a waiting time of 60 seconds. As the catalytic active sites removed by ammonia oxidation during the pulse process were released, the current of the purifier increased from 110A during poisoning to 210A, recovering to near the initial theoretical performance level. During the subsequent 60-second waiting period, as ammonia in the feed gas gradually occupied the active sites of the catalyst, the current of the electrochemical purifier again showed a decreasing trend, gradually decreasing from 210A to 145A over the remaining waiting time. The decrease process was as follows... Figure 3 As shown in section C.

[0047] After the waiting time, the voltage of the pulse power supply increases to the pulse potential of 17.5V and pulses at this potential for 15 seconds. After the pulse time ends, the operating voltage of the pulse power supply returns to 2.5V. At this time, the operating current of the purifier recovers from 145A before the pulse to the theoretical performance level of 210A, and then continues to decrease again with the waiting time. Figure 3 As shown in section D, the entire purifier continues to operate in a cycle of a single waiting time and a single pulse time until the next pulse voltage is applied.

[0048] In the operation of electrochemical pulse ammonia removal technology, the pulse power supply used needs to be customized according to actual requirements. Its main function is to output a series of high-voltage DC pulse signals according to parameter settings, thereby eliminating the impact of ammonia poisoning on the membrane electrode assembly and reducing the performance of the purifier. During the electrochemical pulse ammonia removal operation, the flow rate of the feed gas and the ammonia content in the mixed gas can be changed according to the actual operating conditions. Simultaneously, the waiting time and pulse time can be adjusted, which not only effectively optimizes the electrochemical pulse ammonia removal effect but also reduces the impact on other components of the electrochemical purifier and minimizes energy loss. Furthermore, since the electrochemical purifier is similar to a proton exchange membrane fuel cell, the voltage of the hydrogen purifier needs to be monitored in real time during the pulse ammonia removal operation to ensure that the actual operating voltage of the hydrogen purifier is below 25V, preventing high potential damage to the membrane electrode assembly in the purifier.

[0049] Furthermore, the flow rate of the mixed gas applied to the hydrogen purifier is between 36.26 L / min and 37.74 L / min.

[0050] Optionally, the flow rate of the mixed gas applied to the hydrogen purifier can be 36.26 L / min, 36.27 L / min, 36.28 L / min, 36.29 L / min, 36.30 L / min, 37.71 L / min, 37.72 L / min, 37.73 L / min, or 37.74 L / min.

[0051] Preferably, the flow rate of the mixed gas applied to the hydrogen purifier in this technical solution is 37 L / min.

[0052] Furthermore, the flow rate of hydrogen introduced into the cathode of the hydrogen purifier is between 29.4 L / min and 30.6 L / min.

[0053] Optionally, the flow rate of hydrogen introduced into the cathode of the hydrogen purifier can be any one of 29.40 L / min, 29.54 L / min, 29.67 L / min, 29.84 L / min, 29.95 L / min, 30.00 L / min, 30.01 L / min, 30.08 L / min, 30.23 L / min, 30.30 L / min, 30.34 L / min, 30.42 L / min, 30.47 L / min, 30.51 L / min, and 30.59 L / min.

[0054] Preferably, the flow rate of hydrogen introduced into the cathode of the hydrogen purifier is 30.00 L / min.

[0055] Furthermore, the waiting voltage is between 2.47V and 2.53V.

[0056] Optionally, the standby voltage is any one of 2.47V, 2.48V, 2.49V, 2.50V, 2.51V, 2.52V, and 2.53V.

[0057] Preferably, the standby voltage is 2.50V.

[0058] Furthermore, the waiting time is between 59.4s and 60.6s.

[0059] Optionally, the waiting time can be any one of 59.4s, 59.5s, 59.6s, 59.7s, 59.8s, 59.9s, 60.0s, 60.1s, 60.2s, 60.3s, 60.4s, 60.5s, 60.51s, 60.52s, 60.53s, 60.54s, 60.55s, 60.56s, 60.57s, 60.58s, 60.59s, or 60.60s.

[0060] Preferably, the waiting time is 60 seconds.

[0061] Furthermore, the pulse voltage is between 17.32V and 17.67V.

[0062] Optionally, the pulse voltage can be any one of 17.32V, 17.33V, 17.34V, 17.35V, 17.36V, 17.37V, 17.38V, 17.39V, 17.40V, 17.41V, 17.42V, 17.43V, 17.44V, 17.45V, 17.46V, 17.47V, 17.48V, 17.49V, 17.50V, and 17.51V.

[0063] Preferably, the standby voltage is 17.5V.

[0064] Furthermore, the waiting time is between 14.85s and 15.15s.

[0065] Optionally, the waiting time can be any one of 14.85s, 14.86s, 14.87s, 14.88s, 14.89s, 14.90s, 14.91s, 14.92s, 14.93s, 14.94s, 14.95s, 14.96s, 14.97s, 14.98s, 14.99s, 15.00s, 15.01s, 15.02s, 15.03s, or 15.04s.

[0066] Preferably, the waiting time is 15 seconds.

[0067] Furthermore, the temperature is set between 79.2°C and 80.8°C.

[0068] Optionally, the set temperature can be any one of 79.20°C, 79.21°C, 79.22°C, 79.23°C, 79.24°C, 79.25°C, 79.26°C, 79.27°C, 79.28°C, 79.29°C, 79.30°C, 79.31°C, 79.32°C, 79.33°C, 79.34°C, 79.35°C, 79.36°C, 79.37°C, 79.38°C, or 80°C.

[0069] Preferably, the temperature is set to 80°C.

[0070] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0071] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0072] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0073] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0074] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0075] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A pulse ammonia removal method, characterized in that, The pulsed ammonia removal method is applicable to a hydrogen purifier, which is equipped with a membrane electrode, comprising a catalytic layer and a proton exchange membrane. The pulsed ammonia removal method is used to remove ammonia located on the catalytic layer and the proton exchange membrane. The ammonia removal method includes: When the hydrogen purifier is under set conditions, a set proportion of mixed gas is introduced into the anode of the hydrogen purifier, and hydrogen is introduced into the cathode of the hydrogen purifier. A pulse voltage is supplied to the hydrogen purifier by a pulse power supply to cause the ammonia attached to the catalyst layer and the proton exchange membrane to undergo an oxidation reaction, thereby separating the ammonia from the catalyst layer and the proton exchange membrane. The mixed gas includes hydrogen and ammonia, the set condition is that the hydrogen purifier is at a set temperature, and the set ratio is that the ratio of hydrogen to ammonia is in the range of (99~99.9):(1~0.1).

2. The pulse ammonia removal method according to claim 1, characterized in that, Prior to the step of supplying a pulse voltage to the hydrogen purifier via a pulse power supply, the following steps are included: A standby voltage is applied to the hydrogen purifier; The cumulative waiting time for the aforementioned waiting voltage; When the waiting time is the first duration, the pulse voltage is applied to the hydrogen purifier.

3. The pulse ammonia removal method according to claim 2, characterized in that, The step of applying the pulse voltage to the hydrogen purifier further includes: The cumulative pulse duration after the pulse voltage is applied; When the pulse duration is the second duration, the waiting voltage continues to be supplied to the hydrogen purifier, and the step of accumulating the waiting time of the waiting voltage is repeated until the mixed gas is stopped from being supplied to the hydrogen purifier.

4. The pulse ammonia removal method according to claim 1, characterized in that, The flow rate of the mixed gas applied to the hydrogen purifier is between 36.26 L / min and 37.74 L / min.

5. The pulse ammonia removal method according to claim 1, characterized in that, The flow rate of hydrogen introduced into the cathode of the hydrogen purifier is between 36.26 L / min and 37.74 L / min.

6. The pulse ammonia removal method according to claim 2, characterized in that, The standby voltage is between 2.47V and 2.53V.

7. The pulse ammonia removal method according to claim 2, characterized in that, The waiting time is between 59.4s and 60.6s.

8. The pulse ammonia removal method according to claim 3, characterized in that, The pulse voltage is between 17.32V and 17.67V.

9. The pulse ammonia removal method according to claim 3, characterized in that, The pulse duration is between 14.85s and 15.15s.

10. The pulse ammonia removal method according to claim 1, characterized in that, The set temperature is between 79.2°C and 80.8°C.

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