Oxygen adding and corrosion preventing device and method for urea hydrolysis system

Abstract

The invention discloses an oxygen adding and corrosion preventing device and method for a urea hydrolysis system, and belongs to the technical field of urea hydrolysis ammonia preparation and denitration. According to the device disclosed by the invention, by arranging the detection system, the control system, the integrated oxygen supply system and the gas micropore distributor, parameter monitoring in the urea hydrolysis process is realized, and the oxygen flow and the introduction time of the integrated oxygen supply system are dynamically controlled through the control system, so that a relatively stable passivation film is generated by oxygen and a system material; therefore, the corrosion rate in the urea hydrolysis system is slowed down; and the gas micropore distributor is arranged inside the urea hydrolysis reactor and is used for uniformly distributing the introduced oxygen, so that the technical problem that the hydrolyzer is seriously corroded in the existing urea hydrolysis process is obviously solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of urea hydrolysis to produce ammonia and denitrification, and in particular relates to an oxygenation and corrosion prevention device and method for a urea hydrolysis system. Background Art

[0002] Nitrogen oxides (NOx) contained in flue gas from thermal power plants are a major source of air pollution, photochemical smog, and acid rain. These harmful gases not only pose a threat to human health but also cause long-term damage to the ecological environment, such as soil acidification, water eutrophication, and vegetation damage. To effectively control NOx emissions, selective catalytic reduction (SCR) denitrification (DNO) technology is widely used in industry. Due to its high denitrification efficiency, stable operating performance, and low operating costs, this technology has been widely adopted in thermal power plant flue gas treatment both domestically and internationally. The core principle of SCR DNO is to use a reducing agent, under the action of a catalyst, to convert NOx in flue gas into harmless nitrogen and water, thereby achieving clean emissions. Ammonia, liquid ammonia, or urea are commonly used as reducing agents. While ammonia and liquid ammonia are highly reactive, they pose safety risks in practical applications due to their flammability, explosiveness, corrosiveness, and high storage and transportation risks. In contrast, urea, as a solid compound, offers advantages such as high stability, easy transportation and storage, and excellent safety, making it an ideal raw material for ammonia production. Urea hydrolysis or pyrolysis at high temperatures produces ammonia, which then acts as a reducing agent in the denitrification reaction. This process not only avoids the safety risks associated with the direct use of aqueous or liquid ammonia, but also reduces operating costs while maintaining denitrification efficiency. Furthermore, urea-to-ammonia technology can be used in conjunction with other flue gas purification systems to further enhance overall environmental performance. Consequently, it is being adopted by an increasing number of thermal power plants, becoming a relatively safe, reliable, and economically viable solution among current selective catalytic reduction denitrification technologies.

[0003] Currently, most thermal power plants use urea hydrolysis technology to produce ammonia from urea. Although hydrolyzers are often made of corrosion-resistant 316L stainless steel, the intermediate products generated during the urea hydrolysis process, such as ammonium carbamate and cyanic acid, combine with residual chloride ions in the urea solution to form multiple corrosive media, corroding the stainless steel equipment and pipelines within the hydrolysis system. This results in shortened equipment life, increased operation and maintenance costs, and increased safety hazards. Traditional corrosion prevention methods primarily include selecting more corrosion-resistant materials and applying anti-corrosion coatings. However, these methods have significant limitations. For example, high-performance alloy materials are expensive and difficult to process, organic coatings are easily damaged by the high-temperature hydrolysis environment, and inorganic coatings face the problem of insufficient adhesion to the substrate. These methods cannot fundamentally solve the corrosion problem of urea hydrolysis systems.

[0004] Dissolved oxygen in urea hydrolysis solutions acts as an anodic corrosion inhibitor, playing a key role in maintaining the stability of the passive film on stainless steel surfaces. To ensure the formation of a complete and dense passive protective layer on the metal surface, the oxygen concentration in the medium must be strictly controlled above a critical threshold. Therefore, developing an efficient, economical, and reliable oxygenation and corrosion protection device and method for urea hydrolysis systems is of great practical significance for ensuring the long-term stable operation and extending the service life of industrial equipment. Summary of the Invention

[0005] The object of the present invention is to provide an oxygenation and corrosion prevention device and method for a urea hydrolysis system, so as to solve the technical problem of severe corrosion of the hydrolyzer in the existing urea hydrolysis process.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The invention discloses an oxygenation and corrosion prevention device for a urea hydrolysis system, comprising a detection system, a control system, an integrated oxygen supply system, a urea hydrolysis reactor and a gas microporous distributor; the gas microporous distributor; the gas microporous distributor is provided in both the gas phase zone and the liquid phase zone in the urea hydrolysis reactor; the detection system and the gas microporous distributor are internally connected and electrically connected to the control system; after the integrated oxygen supply system is electrically connected to the control system, it is connected to the gas microporous distributor in the liquid phase zone.

[0008] Furthermore, the integrated oxygen supply system includes an air compressor, a molecular sieve adsorber, an oxygen storage tank, a pressure reducing valve, a flow regulating valve, and an electric heating and heating module connected in sequence; the electric heating and heating module is connected to a gas microporous distributor in the liquid phase zone; the pressure reducing valve and the flow regulating valve are electrically connected to a control system.

[0009] Furthermore, the electric heating module is equipped with a built-in PID temperature controller.

[0010] Furthermore, a drain hole is provided at the bottom of the liquid phase region in the urea hydrolysis reactor, and a hydrolysis drain valve is provided to the drain hole via a pipeline; the hydrolysis drain valve is electrically connected to a control system.

[0011] Furthermore, a gas-producing hole is provided at the top of the gas phase zone in the urea hydrolysis reactor; the gas-producing hole denitrates the flue gas through a gas-producing conveying pipe.

[0012] Furthermore, the detection system includes a gas phase monitoring device and a liquid phase monitoring device; the gas phase monitoring device and the liquid phase monitoring device are respectively connected to the gas phase region and the liquid phase region in the urea hydrolysis reactor, and the gas phase monitoring device and the liquid phase monitoring device are electrically connected to the control system.

[0013] Furthermore, the liquid phase monitoring device includes an oxygen concentration sensor, a chloride ion sensor, an iron ion meter and a corrosion monitor.

[0014] Furthermore, the gas phase monitoring device includes an oxygen concentration detector and an oxygen temperature monitor.

[0015] Furthermore, an auxiliary heater is connected to the liquid phase region in the urea hydrolysis reactor.

[0016] The present invention also discloses a method for using the above-mentioned urea hydrolysis system oxygenation and anti-corrosion device, comprising the following steps:

[0017] Turn on the detection system and control system to monitor the temperature, pressure, oxygen concentration, corrosion rate, and iron ion concentration in the urea hydrolysis reactor in real time, start the integrated oxygen supply system to supply oxygen to the urea hydrolysis reactor, and finally carry out the urea hydrolysis reaction;

[0018] During the reaction process, the temperature, pressure, oxygen concentration, corrosion rate and iron ion concentration signals detected by the detection system are fed back to the control system, and the control system dynamically controls the oxygen flow rate and introduction time of the integrated oxygen supply system;

[0019] The flow rate of the oxygen is 10-100 mL / min, and the introduction time is 10%-50% of the urea hydrolysis reaction time;

[0020] The temperature in the urea hydrolysis reactor is 140-180° C., and the pressure is 0.5-1.5 MPa.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention discloses an oxygenation and corrosion prevention device for a urea hydrolysis system. By providing a detection system, a control system, an integrated oxygen supply system, and a gas microporous distributor, parameter monitoring during the urea hydrolysis process is achieved. The flow rate and introduction time of oxygen in the integrated oxygen supply system are dynamically controlled by the control system, so that a relatively stable passivation film is formed between oxygen and system materials, thereby slowing down the corrosion rate inside the urea hydrolysis system. The gas microporous distributor is arranged inside a urea hydrolysis reactor and is used to evenly distribute the introduced oxygen, significantly solving the technical problem of severe corrosion of the hydrolyzer in the existing urea hydrolysis process.

[0023] Furthermore, the detection system includes a gas phase monitoring device and a liquid phase monitoring device, which can realize oxygen concentration monitoring, chloride ion monitoring, iron ion monitoring and corrosion monitoring system in the system, detect chloride ions, and discharge the hydrolyzer in time. The iron ion and corrosion monitoring system is used to evaluate the corrosion condition of the system and evaluate the corrosion condition of the system in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the overall structure of the oxygenation and corrosion prevention device of the urea hydrolysis system of the present invention;

[0025] Among them: 1-detection system; 2-control system; 3-gas phase monitoring device; 4-liquid phase monitoring device; 5-air compressor; 6-molecular sieve adsorber; 7-oxygen storage tank; 8-pressure reducing valve; 9-flow regulating valve; 10-electric heating and temperature raising module; 11-gas microporous distributor; 12-hydrolysis drain valve; 13-urea hydrolysis reactor; 14-auxiliary heater. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] The present invention is described in further detail below with reference to the accompanying drawings:

[0029] See also Figure 1As shown, the present invention discloses an oxygenation and corrosion prevention device for a urea hydrolysis system, comprising a detection system 1, a control system 2, an integrated oxygen supply system, a urea hydrolysis reactor 13 and a gas microporous distributor 11; wherein the detection system 1 comprises a gas phase monitoring device 3 and a liquid phase monitoring device 4, which are respectively used to detect the oxygen concentration and temperature of the system; the liquid phase monitoring device 4 is used to monitor the oxygen content, chloride ions and corrosion conditions in the liquid phase in the urea hydrolysis reactor in real time, and comprises an oxygen concentration sensor, a chloride ion sensor, an iron ion meter and a corrosion monitor; the control system 2 is used to control the flow rate and introduction time of oxygen in the integrated oxygen supply system, as well as the sewage discharge of the urea hydrolysis system according to the relevant results of the monitoring system 1; the control system 2 also includes a human-computer interaction interface for displaying monitoring data and setting control parameters.

[0030] The integrated oxygen supply system includes an air compressor 5, a molecular sieve adsorber 6, an oxygen storage tank 7, a pressure reducing valve 8, a flow regulating valve 9, and an electric heating and heating module 10 connected in sequence. The electric heating and heating module 10 is connected to a gas microporous distributor 11 in the liquid phase; the pressure reducing valve 8 and the flow regulating valve 9 are electrically connected to a control system 2; the oxygen storage tank 7 is connected to the gas microporous distributor 11 through the pressure reducing valve 8 and the flow regulating valve 9, and the gas microporous distributor 11 is arranged inside a urea hydrolysis reactor 13 for evenly distributing the oxygen introduced; the electric heating and heating module 10 is equipped with a built-in PID temperature controller to maintain the oxygen delivery temperature at 120-150°C.

[0031] The above-mentioned device can realize dynamic oxygen control: after the hydrolysis reaction is started, the oxygen injection rate is controlled to 30-90mL / min through the flow control valve 9, and the oxygen addition time accounts for 15%-40% of the total reaction cycle. The oxygen concentration is monitored in real time by the oxygen concentration real-time monitoring system to maintain the appropriate oxygen concentration and keep the passivation layer intact; closed-loop control mechanism: the corrosion rate of the reactor inner wall material is obtained in real time through the online corrosion monitor. When the corrosion rate exceeds 0.075mm / a, the oxygen flow rate is automatically increased to 120%-150% of the set value, and the auxiliary heater 14 is started to maintain the system reaction temperature in the range of 145-155℃.

[0032] The liquid phase monitoring device 4 includes an oxygen concentration sensor, a chloride ion sensor, an iron ion meter and a corrosion monitor; the gas phase monitoring device 3 includes an oxygen concentration detector and an oxygen temperature monitor; the control system 2 is used to analyze the oxygen concentration and timely detect the amount of oxygen added; detect chloride ions and timely discharge the hydrolyzer; the iron ion and corrosion monitoring system is used to evaluate the corrosion condition of the system and timely evaluate the corrosion condition of the system.

[0033] The flow rate of the oxygen is 10-100 mL / min, and the introduction time is 10%-50% of the urea hydrolysis reaction time.

[0034] The temperature in the urea hydrolysis reactor 13 is controlled to be 140-180° C. and the pressure is controlled to be 0.5-1.5 MPa.

[0035] The present invention also discloses a method for using the above-mentioned urea hydrolysis system oxygenation and anti-corrosion device, comprising the following steps:

[0036] The following steps are involved:

[0037] The detection system 1 and the control system 2 are turned on to detect the temperature, pressure, oxygen concentration, corrosion rate and iron ion concentration in the urea hydrolysis reactor 13 in real time, and the integrated oxygen supply system is started to supply oxygen to the urea hydrolysis reactor 13, and finally the urea hydrolysis reaction is carried out;

[0038] During the reaction process, the temperature, pressure, oxygen concentration, corrosion rate and iron ion concentration signals detected by the detection system 1 are fed back to the control system 2, and the control system 2 dynamically controls the oxygen flow rate and introduction time of the integrated oxygen supply system;

[0039] The flow rate of the oxygen is 10-100 mL / min, and the introduction time is 10%-50% of the urea hydrolysis reaction time;

[0040] The temperature in the urea hydrolysis reactor 13 is 140-180° C., and the pressure is 0.5-1.5 MPa.

[0041] More specific steps are shown in the following examples:

[0042] Example 1

[0043] Step 1: System startup and preprocessing

[0044] Start the monitoring system 1 and the control system 2, and use the gas phase monitoring device 3 and the liquid phase monitoring device 4 to monitor the temperature, pressure, oxygen concentration, corrosion rate, and iron ion concentration in the reactor in real time. Start the air compressor 5 and pass the compressed air into the molecular sieve adsorber 6 to remove moisture and CO2 from the air, obtaining oxygen with a purity of ≥99% and storing it in the oxygen storage tank 7;

[0045] Step 2: Oxygen introduction and parameter control

[0046] Open the pressure reducing valve 8 and the flow regulating valve 9, set the oxygen flow rate to 50mL / min, and preheat the oxygen to 120℃ through the electric heating module 10 to prevent the low-temperature oxygen from entering the reactor and causing local condensation. The preheated oxygen is evenly injected into the reactor of the urea hydrolysis reactor 13 through the gas microporous distributor 11. The micropore diameter of the gas microporous distributor 11 is 20μm and the distribution density is 200 pores / m 2, to ensure that oxygen and urea solution are fully in contact. Initially (0-30% reaction time): high flow rate (80-100 mL / min) to quickly form a passivation layer; mid-term (30%-70% reaction time): reduce to 50 mL / min to maintain the passivation effect. Late (70%-100% reaction time): stop oxygen to reduce side reactions;

[0047] Step 3: Online monitoring

[0048] The corrosion situation is monitored in a timely manner through the oxygen concentration, corrosion probe and iron ion content in the liquid phase, so as to dynamically adjust the oxygen flow rate. The main corrosive ions are monitored through the chloride ion monitoring device. When the index range is exceeded, the sewage control is carried out in time, and the temperature in the urea hydrolysis reactor is controlled at 160℃ and the pressure at 1.2MPa.

[0049] Step 4: Blowdown control and wastewater treatment

[0050] When the chloride ion concentration is greater than 200 mg / L or Fe 3+ When the concentration is continuously greater than 3 mg / L: turn off the oxygen supply and reduce the reactor temperature to 150°C; open the bottom hydrolysis drain valve 12 to discharge 10% to 15% of the reaction solution into the neutralization tank (add NaOH to adjust the pH to 7 to 8). After draining, add an equal amount of fresh urea solution and raise the temperature and pressure again to the set value.

[0051] Example 2

[0052] Step 1: System startup and preprocessing

[0053] Start the monitoring system 1 and the control system 2, and use the gas phase monitoring device 3 and the liquid phase monitoring device 4 to monitor the temperature, pressure, oxygen concentration, corrosion rate, and iron ion concentration in the reactor in real time. Start the air compressor 5 and pass the compressed air into the molecular sieve adsorber 6 to remove moisture and CO2 from the air, obtaining oxygen with a purity of ≥99% and storing it in the oxygen storage tank 7;

[0054] Step 2: Oxygen introduction and parameter control

[0055] Open the pressure reducing valve 8 and the flow regulating valve 9, set the oxygen flow rate to 50mL / min, and preheat the oxygen to 120℃ through the electric heating module 10 to prevent the low-temperature oxygen from entering the reactor and causing local condensation. The preheated oxygen is evenly injected into the reactor of the urea hydrolysis reactor 13 through the gas microporous distributor 11. The micropore diameter of the gas microporous distributor 11 is 20μm and the distribution density is 200 pores / m 2, to ensure that oxygen and urea solution are fully in contact. Initially (0-30% reaction time): high flow rate (80-100 mL / min) to quickly form a passivation layer; mid-term (30%-70% reaction time): reduce to 50 mL / min to maintain the passivation effect. Late (70%-100% reaction time): stop oxygen to reduce side reactions;

[0056] Step 3: Online monitoring

[0057] The corrosion situation is monitored in a timely manner through the oxygen concentration, corrosion probe and iron ion content in the liquid phase, so as to dynamically adjust the oxygen flow rate. The main corrosive ions are monitored through the chloride ion monitoring device. When the index range is exceeded, the sewage control is carried out in time, and the temperature in the urea hydrolysis reactor is controlled at 140℃ and the pressure at 1.5MPa.

[0058] Step 4: Blowdown control and wastewater treatment

[0059] When the chloride ion concentration is greater than 200 mg / L or Fe 3+ When the concentration is continuously greater than 3 mg / L: turn off the oxygen supply and reduce the reactor temperature to 150°C; open the bottom hydrolysis drain valve 12 to discharge 10% to 15% of the reaction solution into the neutralization tank (add NaOH to adjust the pH to 7 to 8). After draining, add an equal amount of fresh urea solution and raise the temperature and pressure again to the set value.

[0060] Example 3

[0061] Step 1: System startup and preprocessing

[0062] Start the monitoring system 1 and the control system 2, and use the gas phase monitoring device 3 and the liquid phase monitoring device 4 to monitor the temperature, pressure, oxygen concentration, corrosion rate, and iron ion concentration in the reactor in real time. Start the air compressor 5 and pass the compressed air into the molecular sieve adsorber 6 to remove moisture and CO2 from the air, obtaining oxygen with a purity of ≥99% and storing it in the oxygen storage tank 7;

[0063] Step 2: Oxygen introduction and parameter control

[0064] Open the pressure reducing valve 8 and the flow regulating valve 9, set the oxygen flow rate to 50mL / min, and preheat the oxygen to 120℃ through the electric heating module 10 to prevent the low-temperature oxygen from entering the reactor and causing local condensation. The preheated oxygen is evenly injected into the reactor of the urea hydrolysis reactor 13 through the gas microporous distributor 11. The micropore diameter of the gas microporous distributor 11 is 20μm and the distribution density is 200 pores / m 2, to ensure that oxygen and urea solution are fully in contact. Initially (0-30% reaction time): high flow rate (80-100 mL / min) to quickly form a passivation layer; mid-term (30%-70% reaction time): reduce to 50 mL / min to maintain the passivation effect. Late (70%-100% reaction time): stop oxygen to reduce side reactions;

[0065] Step 3: Online monitoring

[0066] The corrosion situation is monitored in a timely manner through the oxygen concentration, corrosion probe and iron ion content in the liquid phase, so as to dynamically adjust the oxygen flow rate. The main corrosive ions are monitored through the chloride ion monitoring device. When the index range is exceeded, the sewage control is carried out in time. The temperature in the urea hydrolysis reactor is controlled at 180℃ and the pressure is controlled at 0.5MPa.

[0067] Step 4: Blowdown control and wastewater treatment

[0068] When the chloride ion concentration is greater than 200 mg / L or Fe 3+ When the concentration is continuously greater than 3 mg / L: turn off the oxygen supply and reduce the reactor temperature to 150°C; open the bottom hydrolysis drain valve 12 to discharge 10% to 15% of the reaction solution into the neutralization tank (add NaOH to adjust the pH to 7 to 8). After draining, add an equal amount of fresh urea solution and raise the temperature and pressure again to the set value.

[0069] The present invention is by all arranging gas micropore distributor 11 in the gas phase region and liquid phase region of urea hydrolysis reactor 13, and in conjunction with detection system 1 real-time monitoring key parameters such as oxygen concentration, corrosion rate, iron ion, realizes uniform distribution and dynamic regulation of oxygen.Control system 2 dynamically adjusts oxygen supply and passage time according to feedback data, can effectively suppress corrosion, and avoids excessive oxygen from affecting hydrolysis reaction efficiency.Secondly, the integrated oxygen supply system (air compressor 5 → molecular sieve adsorber 6 → oxygen storage tank 7 → pressure reducing valve 8 → flow regulating valve 9 → electric heating temperature raising module 10) adopted realizes preparation, purification, storage and accurate delivery of oxygen. The electric heating module 10 has a built-in PID temperature controller to ensure that the oxygen temperature matches the reaction conditions, avoid low-temperature oxygen disturbing the reaction system, and improve the anti-corrosion effect; and the detection system 1 covers comprehensive monitoring of the gas phase (oxygen concentration, temperature) and liquid phase (oxygen concentration, chloride ions, iron ions, corrosion rate), and accurately judges the corrosion risk through multi-sensor linkage. For example, the iron ion concentration and corrosion rate data can directly reflect the corrosion status of the equipment and provide a scientific basis for oxygen supply regulation; in addition, a drain hole and a hydrolysis drain valve 12 are set at the bottom of the liquid phase area to regularly remove corrosion products and impurities and reduce deposition corrosion. The liquid phase area is connected to an auxiliary heater 14 to ensure that the reaction temperature is stable and avoid aggravated corrosion caused by local low temperature. The gas production hole in the gas phase area is directly connected to the denitrification system to achieve efficient recovery and utilization of ammonia and improve overall energy efficiency.

[0070] The above content is only for explaining the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A urea hydrolysis system oxygenation and anti-corrosion device, characterized in that: The invention comprises a detection system (1), a control system (2), an integrated oxygen supply system, a urea hydrolysis reactor (13) and a gas microporous distributor (11); the gas microporous distributor (11); the gas phase zone and the liquid phase zone in the urea hydrolysis reactor (13) are both provided with the gas microporous distributor (11); the detection system (1) and the gas microporous distributor (11) are internally connected and electrically connected to the control system (2); after the integrated oxygen supply system is electrically connected to the control system (2), it is connected to the gas microporous distributor (11) in the liquid phase zone.

2. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 1, characterized in that: The integrated oxygen supply system comprises an air compressor (5), a molecular sieve adsorber (6), an oxygen storage tank (7), a pressure reducing valve (8), a flow regulating valve (9), and an electric heating and temperature raising module (10) which are connected in sequence; the electric heating and temperature raising module (10) is connected to a gas microporous distributor (11) in a liquid phase region; and the pressure reducing valve (8) and the flow regulating valve (9) are electrically connected to a control system (2).

3. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 2, characterized in that: The electric heating temperature raising module (10) is equipped with a built-in PID temperature controller.

4. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 1, characterized in that: A drain hole is also provided at the bottom of the liquid phase region in the urea hydrolysis reactor (13), and the drain hole is connected to a hydrolysis drain valve (12) via a pipeline; the hydrolysis drain valve (12) is electrically connected to the control system (2).

5. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 1, characterized in that: A gas-generating hole is also provided at the top of the gas phase region in the urea hydrolysis reactor (13); the gas-generating hole carries out flue gas denitration through a gas-generating conveying pipe.

6. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 1, characterized in that: The detection system (1) comprises a gas phase monitoring device (3) and a liquid phase monitoring device (4); the gas phase monitoring device (3) and the liquid phase monitoring device (4) are respectively connected to the gas phase region and the liquid phase region in the urea hydrolysis reactor (13), and the gas phase monitoring device (3) and the liquid phase monitoring device (4) are electrically connected to the control system (2).

7. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 6, characterized in that: The liquid phase monitoring device (4) comprises an oxygen concentration sensor, a chloride ion sensor, an iron ion meter and a corrosion monitor.

8. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 6, characterized in that: The gas phase monitoring device (3) comprises an oxygen concentration detector and an oxygen temperature monitor.

9. The urea hydrolysis system oxygenation and anti-corrosion device according to claim 1, characterized in that: The liquid phase region in the urea hydrolysis reactor (13) is connected to an auxiliary heater (14).

10. The method for using the oxygenation and corrosion protection device for a urea hydrolysis system according to any one of claims 1 to 9, characterized in that: The following steps are involved: The detection system (1) and the control system (2) are turned on to detect the temperature, pressure, oxygen concentration, corrosion rate and iron ion concentration in the urea hydrolysis reactor (13) in real time, and the integrated oxygen supply system is started to supply oxygen to the urea hydrolysis reactor (13), and finally the urea hydrolysis reaction is carried out; During the reaction process, the temperature, pressure, oxygen concentration, corrosion rate and iron ion concentration signals detected by the detection system (1) are fed back to the control system (2), and the control system (2) dynamically controls the oxygen flow rate and introduction time of the integrated oxygen supply system; The flow rate of the oxygen is 10-100 mL / min, and the introduction time is 10%-50% of the urea hydrolysis reaction time; The temperature in the urea hydrolysis reactor (13) is 140-180°C, and the pressure is 0.5-1.5 MPa.

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