SCAL type inter-cooling system automatic dosing system and method

Abstract

The application belongs to the technical field of chemical corrosion prevention, and relates to an SCAL type intercooling system automatic dosing system and method. The system comprises a dosing system, a control system and an intercooling system. The dosing system is composed of a slow-release agent solution tank, a desalted water tank, a slow-release agent solution tank liquid level meter, a slow-release agent dosing pipeline and a supplementary desalted water pipeline, is equipped with a metering pump, a flow meter and an electric valve, and realizes accurate dosing of the medicament and quantitative supply of the supplementary water. The control system comprises a control device, is used for collecting signals of the flow meters and the liquid level meter in real time, and automatically adjusts the running frequency of the dosing metering pump and the opening and closing of the valve based on a preset control algorithm. The intercooling system comprises an intercooling tower, a condenser and a bypass flow treatment loop. The bypass flow treatment loop continuously purifies part of the circulating cooling water through multi-stage treatment processes such as iron removal, filtration and ion exchange. The application can automatically maintain long-term stability of the corrosion inhibitor concentration in the intercooling system under different working conditions, and effectively improves the corrosion prevention efficiency and the operation reliability of the system.

Description

Technical Field

[0001] This invention belongs to the field of chemical corrosion protection technology, and relates to an automatic chemical dosing system and method for SCAL type intercooling system. Background Technology

[0002] As the main type of newly built thermal power units in northern my country, the SCAL type intercooled system currently faces the problems of a lack of standards and insufficient experience in circulating water quality control. There are no water quality control standards or specifications for this system, both domestically and internationally, and most power plants mainly rely on the water quality requirements provided by equipment manufacturers. However, the indicators proposed by manufacturers mainly focus on preventing alkaline corrosion of aluminum radiators, failing to fully consider the potential hazards caused by corrosion of carbon steel pipes and their byproducts. Furthermore, the actual operating water quality generally fails to meet the manufacturers' requirements, leading to varying degrees of circulating water quality deterioration and abnormal pH increases in the SCAL systems of many power plants during the initial commissioning and long-term operation. Some units have even experienced radiator corrosion and leakage problems.

[0003] To improve water quality, power plants typically employ methods such as water exchange, chemical dosing, or cation exchange bed bypass treatment. While water exchange can alleviate water quality deterioration in the short term, the large storage capacity of the SCAL system (usually nearly 10,000 tons of demineralized water) limits the water exchange rate and purification effect to the power plant's water production capacity. Furthermore, it suffers from high costs and resource waste, contradicting the system's water-saving design principles. Conventional methods of adding ammonia or hydrazine to maintain a slightly alkaline pH also prove ineffective. Although small cation exchange bed bypass treatment can alleviate high pH levels, it cannot fundamentally inhibit carbon steel corrosion.

[0004] To address this, some power plants have experimented with a synergistic treatment approach combining corrosion inhibitors with bypass purification devices. This method forms a stable protective film on the material surface, slowing corrosion during operation and also providing corrosion control during shutdown. However, the operation of the bypass purification device continuously consumes the corrosion inhibitor in the system, leading to a decrease in its concentration and affecting subsequent corrosion inhibition effects. Furthermore, manual dosing makes it difficult to precisely control the dosage during the overall water replacement process, further increasing the complexity of operation and management. Summary of the Invention

[0005] To address the problems in the prior art, this invention provides an automatic chemical dosing system and method for SCAL-type intercooling systems. This system monitors key flow parameters in real time and dynamically adjusts the dosing rate according to a preset algorithm, which can automatically maintain the long-term stability of the corrosion inhibitor concentration in the intercooling system under different operating conditions, effectively improving the system's corrosion resistance and operational reliability.

[0006] To achieve the above objectives, the present invention employs the following technical solution: In a first aspect, the present invention provides an automatic dosing system for an SCAL type intercooled system, comprising: A dosing system includes a slow-release agent solution tank, a demineralized water tank, a slow-release agent solution tank level gauge, a slow-release agent dosing pipeline, and a replenishment demineralized water pipeline. The slow-release agent solution tank level gauge is installed on the slow-release agent solution tank. One end of the slow-release agent dosing pipeline is connected to the slow-release agent solution tank. A slow-release agent dosing metering pump and a slow-release agent dosing flow meter are sequentially installed along the water flow direction on the slow-release agent dosing pipeline. One end of the replenishment demineralized water pipeline is connected to the demineralized water tank. A demineralized water flow meter and a demineralized water electric gate are sequentially installed along the water flow direction on the replenishment demineralized water pipeline. The control system includes a control device; the control device is respectively connected to the level gauge of the slow-release agent solution tank, the flow meter of the slow-release agent dosing, the flow meter of the demineralized water, the metering pump of the slow-release agent dosing, and the signal of the electric gate of the demineralized water. An indirect cooling system includes an indirect cooling tower, a condenser, and a bypass treatment loop. The outlet of the condenser is connected to the inlet of the indirect cooling tower, and the outlet of the indirect cooling tower is connected to the inlet of the condenser, forming a cooling water circulation loop. The inlet of the bypass treatment loop is connected to the outlet pipe of the condenser, and the outlet is connected to the inlet pipe of the condenser. A bypass treatment flow meter is installed on the bypass treatment loop. The other end of the slow-release agent dosing pipeline is connected between the outlet of the bypass treatment loop and the inlet pipe of the condenser. The other end of the demineralized water supply pipeline is connected between the outlet of the bypass treatment loop and the inlet pipe of the condenser. The bypass treatment flow meter is signal-connected to the control device.

[0007] Preferably, the bypass treatment circuit is provided with an iron remover, an activated carbon filter and a mixed bed in sequence along the water flow direction; the other end of the slow-release agent dosing pipeline and the other end of the replenishment demineralized water pipeline are both connected to the outlet side pipeline of the mixed bed.

[0008] Preferably, both the bypass flow meter and the demineralized water flow meter are time-difference ultrasonic flow meters.

[0009] Preferably, the slow-release agent dosing pipeline is also equipped with a slow-release agent dosing electric gate, which is located downstream of the water flow direction of the slow-release agent dosing flow meter and is signal-connected to the control device.

[0010] Preferably, the controlled-release dosing electric gate is connected to the control device via a fourth cable.

[0011] Preferably, the cooling water circulation loop is provided with heat dissipation fins between the intercooler and the condenser along the water flow direction, the water inlet of the heat dissipation fins is connected to the water outlet of the intercooler, and the water outlet of the heat dissipation fins is connected to the water inlet of the condenser.

[0012] Preferably, the slow-release agent dosing pipelines on both sides of the slow-release agent dosing flow meter are provided with straight pipe sections of a first preset length; the replenishment demineralized water pipelines on both sides of the demineralized water flow meter are provided with straight pipe sections of a second preset length; and the bypass treatment circuits on both sides of the bypass treatment flow meter are provided with straight pipe sections of a third preset length.

[0013] Preferably, the slow-release agent flow meter is connected to the control device via a sixth cable; the demineralized water flow meter is connected to the control device via a fifth cable; the bypass flow meter is connected to the control device via a second cable; the slow-release agent solution tank level gauge is connected to the control device via an eighth cable; the slow-release agent metering pump is connected to the control device via a seventh cable; and the demineralized water electric gate is connected to the control device via a third cable.

[0014] Secondly, the present invention provides an automatic dosing method for a SCAL type intercooling system, comprising the following steps: The slow-release agent solution stored in the slow-release agent solution tank is transported and added to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser via the slow-release agent dosing pipeline, through the slow-release agent dosing metering pump and the slow-release agent dosing flow meter. By supplementing the demineralized water pipeline, the demineralized water stored in the demineralized water tank is transported and supplemented to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser through the demineralized water flow meter and the demineralized water electric gate. The liquid level of the slow-release agent solution tank is monitored by the liquid level gauge of the slow-release agent solution tank, the flow rate through the bypass treatment circuit is monitored by the bypass treatment flow meter, the flow rate of the added slow-release agent is monitored by the slow-release agent dosing flow meter, and the flow rate of the added demineralized water is monitored by the demineralized water flow meter. The control device acquires the above monitoring data and generates control commands based on preset logic to control the operating frequency of the slow-release agent metering pump and the opening and closing of the demineralized water electric door. After the cooling water completes heat exchange in the condenser, it is transported to the intercooler tower for cooling through pipelines, and then returns to the condenser to complete the cycle. At the same time, a portion of the cooling water is diverted from the condenser outlet pipeline to the bypass treatment circuit for treatment, and the treated water is returned to the condenser inlet pipeline.

[0015] Preferably, the control device generates control commands based on preset logic to control the operating frequency of the sustained-release dosing pump, including: The first theoretical dosage is calculated when the bypass treatment is running only, using the following formula:

[0016] in, This is the first theoretical dosage; Y represents the flow rate monitored by the bypass flow meter; Y is the target concentration of the slow-release agent set by the system. Density of the sustained-release agent; The second theoretical dosage is calculated when the bypass treatment and demineralized water replenishment are running simultaneously. The calculation formula is as follows:

[0017] in, This is the second theoretical dosage; The flow rate value monitored by the demineralized water flow meter; The maximum output of the sustained-release agent metering pump is set to M; When the demineralized water electric door is closed, the controlled-release agent dosing pump is controlled to do the dosage according to the first theoretical dosage. It operates at the corresponding first frequency; When the demineralized water electric door is opened, if If M ≤ M, then control the sustained-release agent metering pump to dispense the agent according to the second theoretical dosage. The corresponding second frequency operation; if If M is selected, the controlled-release agent metering pump will operate at the third frequency corresponding to M, and after the demineralized water electric door closes, a delay will occur. Then switch the sustained-release dosing pump to operate at the first frequency. The calculation formula is:

[0018] Where T is the duration of the demineralized water electric door being opened this time.

[0019] Compared with the prior art, the present invention has the following beneficial effects: This system achieves precise and dynamic management of reagent concentration through dosing, control, and intercooling systems. Specifically, the configuration of metering pumps and flow meters in the dosing system ensures accurate and controllable dosage of the slow-release agent, while level gauges and electric gates guarantee the reliability of reagent and demineralized water supply and shut-off. The control system, through signal connections, enables the control device to collect flow and level data in real time and automatically adjust the dosing pumps and valves based on algorithms, achieving a leap from manual operation to fully automatic closed-loop control. The connection between the bypass treatment loop and the main circulation in the intercooling system, combined with its flow monitoring and optimized layout of dosing points, allows the reagent to be directly added to the purified water flow and uniformly enter the main system, effectively solving the problem of reagent concentration fluctuations caused by bypass consumption and makeup water dilution. This automatically maintains the long-term stability of the corrosion inhibitor concentration under different operating conditions, significantly improving the overall corrosion prevention efficiency and operational reliability of the system. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of an automatic dosing system for an intercooled system of the SCAL type according to the present invention.

[0022] The components are as follows: 101. Slow-release agent solution tank; 102. Demineralized water tank; 103. Slow-release agent solution tank level gauge; 104. Bypass flow meter; 105. Slow-release agent dosing electric gate; 106. Slow-release agent dosing flow meter; 107. Slow-release agent dosing metering pump; 108. Demineralized water electric gate; 109. Demineralized water flow meter; 110. Slow-release agent dosing pipeline; 111. Supplementary demineralized water pipeline; 201. Main unit DCS system; 202. Control device; 203. First cable; 204. Second cable; 205. Third cable; 206. Fourth cable; 207. Fifth cable; 208. Sixth cable; 209. Seventh cable; 210. Eighth cable; 301. Indirect cooling tower; 302. Heat dissipation fins; 303. Condenser; 304. Iron separator; 305. Activated carbon filter; 306. Mixed bed. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0025] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0026] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and 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 of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0027] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0028] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0029] The present invention will now be described in further detail with reference to the accompanying drawings: The first objective of this invention is to provide an automatic dosing system for SCAL type intercooled systems, such as... Figure 1 As shown, it includes: A dosing system includes a slow-release agent solution tank 101, a demineralized water tank 102, a slow-release agent solution tank level gauge 103, a slow-release agent dosing pipeline 110, and a replenishment demineralized water pipeline 111. The slow-release agent solution tank level gauge 103 is installed on the slow-release agent solution tank 101. One end of the slow-release agent dosing pipeline 110 is connected to the slow-release agent solution tank 101. A slow-release agent dosing metering pump 107 and a slow-release agent dosing flow meter 106 are sequentially installed on the slow-release agent dosing pipeline 110 along the water flow direction. One end of the replenishment demineralized water pipeline 111 is connected to the demineralized water tank 102. A demineralized water flow meter 109 and a demineralized water electric gate 108 are sequentially installed on the replenishment demineralized water pipeline 111 along the water flow direction. The control system includes a control device 202; the control device 202 is connected to the level gauge 103 of the slow-release agent solution tank, the flow meter 106 of the slow-release agent dosing, the flow meter 109 of the demineralized water, the metering pump 107 of the slow-release agent dosing, and the electric gate 108 of the demineralized water. An indirect cooling system is provided, comprising an indirect cooling tower 301, a condenser 303, and a bypass treatment loop. The outlet of the condenser 303 is connected to the inlet of the indirect cooling tower 301, and the outlet of the indirect cooling tower 301 is connected to the inlet of the condenser 303, forming a cooling water circulation loop. The inlet of the bypass treatment loop is connected to the outlet pipe of the condenser 303, and the outlet is connected to the inlet pipe of the condenser 303. A bypass treatment flow meter 104 is provided on the bypass treatment loop. The other end of the slow-release agent dosing pipeline 110 is connected between the outlet of the bypass treatment loop and the inlet pipe of the condenser 303. The other end of the demineralized water replenishment pipeline 111 is connected between the outlet of the bypass treatment loop and the inlet pipe of the condenser 303. The bypass treatment flow meter 104 is signal-connected to the control device 202.

[0030] The system collects real-time monitoring data from the slow-release agent solution tank level gauge 103, the slow-release agent dosing flow meter 106, the demineralized water flow meter 109, and the bypass treatment flow meter 104 via the control device 202. Based on preset control logic, it automatically adjusts the operating frequency of the slow-release agent dosing metering pump 107 and the opening and closing of the demineralized water electric door 108. Thus, based on the real-time replenishment water volume and bypass treatment water volume of the intercooling system, it dynamically and accurately calculates and adds the required corrosion inhibitor. This effectively solves the problems of reagent concentration fluctuations caused by traditional manual impact dosing and the inability to compensate for the continuous consumption of reagents in the bypass purification process. It achieves dynamic stability of the corrosion inhibitor concentration in the system under varying operating conditions, significantly improving the overall corrosion resistance and operational safety of the intercooling system.

[0031] For example, the bypass treatment loop is sequentially equipped with an iron remover 304 for removing corrosion products, an activated carbon filter 305 for adsorbing organic matter and residual chemicals, and a mixed bed 306 for deep desalination along the water flow direction. The other end of the slow-release agent dosing pipeline 110 and the other end of the replenished demineralized water pipeline 111 are connected to the outlet side pipeline downstream of the mixed bed 306. This connection method makes full use of the clean water quality after bypass treatment, so that the added corrosion inhibitor and the replenished demineralized water can be fully and evenly mixed with the purified bypass return water before entering the main circulation of the condenser 303, effectively avoiding local uneven concentration or temperature disturbances that may be caused by the direct entry of chemicals and replenished water into the main system. At the same time, setting the dosing point after the mixed bed 306 ensures that the corrosion inhibitor will not be prematurely adsorbed and lost by the activated carbon filter 305 or affected by the ion exchange process of the mixed bed 306, ensuring the full effectiveness and metering accuracy of the added chemicals, thereby further improving the final adjustment accuracy and corrosion prevention stability of the automatic dosing control system.

[0032] For example, considering that both the circulating water and makeup water in the SCAL intercooling system are high-purity demineralized water with extremely low conductivity, traditional electromagnetic flowmeters are difficult to measure accurately. Therefore, both the bypass flowmeter 104 and the demineralized water flowmeter 109 are preferably time-difference ultrasonic flowmeters. This type of flowmeter determines the flow velocity based on the time difference between the propagation of ultrasonic waves in the fluid with and against the flow. Its measurement process does not contact the fluid and has no moving parts, exhibiting excellent adaptability and measurement accuracy for fluids with low conductivity.

[0033] For example, to improve system safety and maintenance convenience, a slow-release agent dosing electric gate 105 is also installed on the slow-release agent dosing pipeline 110, and its installation position is downstream of the slow-release agent dosing flow meter 106 along the water flow direction. The electric gate is signal-connected to the control device 202. This arrangement follows the general installation specifications that require a stable flow field upstream of the flow measurement instrument, ensuring that the flow meter 106 can obtain a fully developed flow state upstream, thereby measuring more accurate instantaneous and cumulative dosing flow data. At the same time, by placing the electric gate 105 downstream of the flow meter 106, rapid and reliable pipeline isolation can be achieved when the system needs maintenance, emergency shutdown, or when the control device 202 logic determines that dosing needs to be cut off. This effectively prevents the corrosion inhibitor solution from leaking uncontrollably or continuing to drip into the system after the pump stops due to siphon or pressure difference, thus protecting the accuracy and safety of the measuring instrument and ensuring strict controllability of the dosing action.

[0034] For example, the control system also includes a main DCS (Distributed Control System) 201; analog signals from field instruments (such as flow meters and level gauges) and control command status signals issued by the control device 202 are all transmitted through the first cable 203 and integrated into the main DCS 201. Simultaneously, the control device 202 has an operation mode selection function, which can switch between local control and remote control modes according to operational needs. In remote control mode, the main DCS 201 acts as a supervisory control system, providing operators with a centralized and intuitive human-machine interface. It can monitor the operating parameters and balancing effect of the entire automatic water distribution system in real time, and, when necessary (such as during automatic control loop maintenance or special operating conditions), issue advanced commands or setpoints to the control device 202 through the main DCS 201, enabling remote intervention and optimization management by operators. In local control mode, the control device 202 independently executes its built-in closed-loop regulation program to ensure the autonomous and reliable operation of the core flow equalization function.

[0035] For example, a heat dissipation fin 302 is provided on the cooling water circulation loop between the intercooler 301 and the condenser 303 along the water flow direction. The water inlet of the heat dissipation fin 302 is connected to the water outlet of the intercooler 301, and the water outlet of the heat dissipation fin 302 is connected to the water inlet of the condenser 303.

[0036] For example, heat dissipation fins 302 are provided along the water flow direction between the intercooler 301 and the condenser 303 in the cooling water circulation loop. The inlet of the fins is connected to the outlet of the intercooler 301, and the outlet is connected to the inlet of the condenser 303. The large-area heat dissipation fins 302 efficiently exchange heat with the air, thereby reducing the temperature of the circulating cooling water carrying the heat of steam condensation in the condenser 303, completing the final release of heat. The cooled circulating water then returns to the condenser 303 to reabsorb the latent heat of the turbine exhaust steam, forming a closed and efficient cooling circulation loop.

[0037] This invention provides continuous and uniform corrosion protection to the key metal surfaces of the entire circulation loop, including a large number of aluminum heat sink fins 302 and carbon steel pipes, by maintaining a stable corrosion inhibitor concentration in the circulating water medium. This effectively prevents serious consequences such as decreased heat dissipation efficiency, increased flow resistance, and even fin corrosion perforation caused by corrosion product deposition, ensuring the thermal performance and structural integrity of the intercooling system during long-term operation.

[0038] For example, the slow-release agent dosing pipelines 110 on both sides of the slow-release agent dosing flowmeter 106 are provided with straight pipe sections of a first preset length; the replenishment demineralized water pipelines 111 on both sides of the demineralized water flowmeter 109 are provided with straight pipe sections of a second preset length; and the bypass treatment loops on both sides of the bypass treatment flowmeter 104 are provided with straight pipe sections of a third preset length. The purpose of this is to eliminate eddies and velocity distribution distortions caused by valves, elbows, or pumps upstream of the flowmeter, and to reduce the impact of back pressure fluctuations on the measurement downstream, thereby providing each flowmeter with a stable, symmetrical, and fully developed fluid profile. This measure ensures that the acquisition of all key flow signals (including dosing amount, replenishment water volume, and bypass treatment water volume) has high reliability and repeatability, laying an accurate data foundation for the control device 202 to perform subsequent complex reagent demand calculations and real-time closed-loop control.

[0039] For example, the control device 202 is connected to the host DCS system 201 via a first cable 203; the slow-release agent dosing flow meter 106 is connected to the control device 202 via a sixth cable 208; the slow-release agent dosing electric gate 105 is connected to the control device 202 via a fourth cable 206; the demineralized water flow meter 109 is connected to the control device 202 via a fifth cable 207; the bypass flow meter 104 is connected to the control device 202 via a second cable 204; the slow-release agent solution tank level gauge 103 is connected to the control device 202 via an eighth cable 210; the slow-release agent dosing metering pump 107 is connected to the control device 202 via a seventh cable 209; and the demineralized water electric gate 108 is connected to the control device 202 via a third cable 205. Preferably, the cables are shielded twisted-pair cables with copper conductors to ensure interference resistance and signal integrity for high-speed data exchange. The second objective of this invention is to provide an automatic dosing method for a SCAL-type intercooling system, comprising the following steps: The slow-release agent solution stored in the slow-release agent solution tank 101 is transported and added to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser 303 via the slow-release agent dosing pipeline 110, through the slow-release agent dosing metering pump 107 and the slow-release agent dosing flow meter 106. By supplementing the demineralized water pipeline 111, the demineralized water stored in the demineralized water tank 102 is transported and supplemented to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser 303 via the demineralized water flow meter 109 and the demineralized water electric gate 108. The liquid level of the slow-release agent solution tank 101 is monitored by the liquid level gauge 103, the flow rate through the bypass treatment circuit is monitored by the bypass treatment flow meter 104, the flow rate of the added slow-release agent is monitored by the slow-release agent dosing flow meter 106, and the flow rate of the added demineralized water is monitored by the demineralized water flow meter 109. The control device 202 acquires the above monitoring data and generates control commands based on preset logic to control the operating frequency of the slow-release agent dosing pump 107 and the opening and closing of the demineralized water electric door 108; at the same time, the control device 202 communicates with the host DCS system 201 to realize data transmission and remote monitoring. After the cooling water completes heat exchange in the condenser 303, it is transported to the intercooler tower 301 for cooling through pipelines, and then returns to the condenser 303 to complete the circulation. At the same time, a portion of the cooling water is diverted from the outlet pipeline of the condenser 303 into the bypass treatment circuit for treatment, and the treated water is returned to the inlet pipeline of the condenser 303.

[0040] This method continuously collects key parameters such as bypass treatment flow rate, demineralized water replenishment flow rate, and chemical dosing flow rate through an integrated instrumentation system. The control device 202 calculates the required dosage to maintain the target chemical concentration in real time based on a preset algorithm, and then automatically adjusts the frequency of the dosing pump. When the system replenishment water volume increases, the dosing rate is increased accordingly to compensate for the dilution effect. After replenishment, a delay compensation mechanism precisely replenishes the amount of chemical missing due to dosing capacity limitations. This invention not only achieves a leap from manual experience-based operation to fully automatic and precise control, but also ensures the long-term stability of the corrosion inhibitor concentration under various operating conditions by incorporating the chemical consumption caused by bypass treatment into the control model. This effectively inhibits the corrosion rate of metal materials in the indirect cooling system, significantly improving the safety and economy of system operation.

[0041] For example, the control device 202 generates control commands based on preset logic to control the operating frequency of the sustained-release dosing pump 107, including: The first theoretical dosage is calculated when the bypass treatment is running only, using the following formula:

[0042] in, This is the first theoretical dosage; Y represents the flow rate monitored by the bypass flow meter 104; Y represents the target concentration of the slow-release agent set by the system. Density of the sustained-release agent; The second theoretical dosage is calculated when the bypass treatment and demineralized water replenishment are running simultaneously. The calculation formula is as follows:

[0043] in, This is the second theoretical dosage; The flow rate value monitored by the demineralized water flow meter 109; The maximum output of the sustained-release agent metering pump 107 is set to M; When the demineralized water electric door 108 is closed, the controlled-release agent dosing pump 107 is controlled to do the dosage according to the first theoretical dosage. It operates at the corresponding first frequency; When the demineralized water electric door 108 is opened, if If M ≤ M, then control the sustained-release agent metering pump 107 to add the agent according to the second theoretical dosage. The corresponding second frequency operation; if If M is selected, the controlled-release agent metering pump 107 will operate at the third frequency corresponding to M, and after the demineralized water electric door 108 closes, a delay will be made for a certain period of time. Then switch the sustained-release dosing pump 107 to operate at the first frequency. The calculation formula is:

[0044] Where T is the duration of the opening of the demineralized water electric door 108.

[0045] Specifically, this invention calculates the basic dosage required to compensate only for bypass treatment losses. First, ensure the reagent balance of the system during steady-state operation; second, when the system requires makeup water, calculate the total dosage required to simultaneously compensate for bypass losses and makeup water dilution. This allows for real-time adjustment of the drug concentration; finally, a judgment and compensation mechanism for the maximum output M of the dosing metering pump is introduced, based on the calculated total demand. When the water supply exceeds the equipment's capacity, it will first be added at its maximum capacity, and after the water replenishment is completed, a precisely calculated delay (T) will be applied. delay Continue replenishing until the insufficient amount of chemicals caused by equipment capacity limitations during water replenishment is completely compensated. This method effectively solves the problem of sudden drop in chemical concentration and delayed recovery that is prone to occur in traditional methods under special operating conditions such as large-flow water replenishment or water replacement. It ensures that the corrosion inhibitor concentration is stably maintained at the set target throughout the entire time period and operating condition range, thereby greatly improving the reliability and effectiveness of corrosion prevention and control.

[0046] Example The slow-release agent solution stored in the slow-release agent solution tank 101 is transported and added to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser 303 via the slow-release agent dosing pipeline 110, through the slow-release agent dosing metering pump 107 and the slow-release agent dosing flow meter 106. By supplementing the demineralized water pipeline 111, the demineralized water stored in the demineralized water tank 102 is transported and supplemented to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser 303 via the demineralized water flow meter 109 and the demineralized water electric gate 108. The liquid level of the slow-release agent solution tank 101 is monitored by the liquid level gauge 103, the flow rate through the bypass treatment circuit is monitored by the bypass treatment flow meter 104, the flow rate of the added slow-release agent is monitored by the slow-release agent dosing flow meter 106, and the flow rate of the added demineralized water is monitored by the demineralized water flow meter 109. The control device 202 acquires the above monitoring data and generates control commands based on preset logic to control the operating frequency of the slow-release agent dosing pump 107 and the opening and closing of the demineralized water electric door 108; at the same time, the control device 202 communicates with the host DCS system 201 to realize data transmission and remote monitoring. After the cooling water completes heat exchange in the condenser 303, it is transported to the intercooler tower 301 for cooling through pipelines, and then returns to the condenser 303 to complete the circulation. At the same time, a portion of the cooling water is diverted from the outlet pipeline of the condenser 303 into the bypass treatment circuit for treatment, and the treated water is returned to the inlet pipeline of the condenser 303.

[0047] The control device 202 generates control commands based on preset logic to control the operating frequency of the sustained-release dosing pump 107, including: The first theoretical dosage is calculated when the bypass treatment is running only, using the following formula:

[0048] in, This is the first theoretical dosage; Y represents the flow rate monitored by the bypass flow meter 104; Y represents the target concentration of the slow-release agent set by the system. Density of the sustained-release agent; The second theoretical dosage is calculated when the bypass treatment and demineralized water replenishment are running simultaneously. The calculation formula is as follows:

[0049] in, This is the second theoretical dosage; The flow rate value monitored by the demineralized water flow meter 109; The maximum output of the sustained-release agent metering pump 107 is set to M; When the demineralized water electric door 108 is closed, the controlled-release agent dosing pump 107 is controlled to do the dosage according to the first theoretical dosage. It operates at the corresponding first frequency; When the demineralized water electric door 108 is opened, if If M ≤ M, then control the sustained-release agent metering pump 107 to add the agent according to the second theoretical dosage. The corresponding second frequency operation; if If M is selected, the controlled-release agent metering pump 107 will operate at the third frequency corresponding to M, and after the demineralized water electric door 108 closes, a delay will be made for a certain period of time. Then switch the sustained-release dosing pump 107 to operate at the first frequency. The calculation formula is:

[0050] Where T is the duration of the opening of the demineralized water electric door 108.

[0051] To verify the effectiveness of this invention, a laboratory simulation test was conducted. The test results show that, in the automatic operation mode, the corrosion inhibitor dosage can be automatically and precisely adjusted according to the real-time replenishment water volume of the intercooling system, thereby effectively maintaining the stability of the agent concentration within the system.

[0052] Specifically, the following parameters were set for the experiment: Bypass treatment fixed flow rate: 1m 3 / h; Demineralized water makeup flow rate: set to 1m 3 / h、2m 3 / h and 3m 3 / h Three typical operating conditions; Maximum output of the sustained-release dosing pump: 0.075m 3 / h; Systemic sustained-release agent target concentration: 30 mg / L; Sustained-release solution density: 1.2 kg / m³ 3 .

[0053] During the experiment, the system operated entirely based on preset automatic control logic, recording and analyzing the dosing behavior under different operating conditions. Detailed experimental data and results are shown in Table 1. Table 1. System test data of the present invention

[0054] Experimental data analysis shows that the automatic dosing system can accurately switch the dosing frequency mode according to changes in water replenishment conditions and effectively maintain a stable chemical concentration. In the first stage (6.3-6.5), under conditions without water replenishment, the system operated at the first frequency, and the corrosion inhibitor concentration remained stable at 0.0297 kg / m³. 3The concentration was close to the design target of 30 mg / L. In the second phase (June 6-8), 24 hours after water replenishment, the system automatically switched to the second frequency, precisely matching the total water volume of "replenishment + bypass," maintaining a concentration of 0.0302 kg / m³. 3 The ideal level was achieved. During the third stage (June 9-11), although water was replenished for another 24 hours, the theoretical dosing demand exceeded the maximum output of the metering pump. Therefore, the system switched to the third frequency (maximum output) and maintained the concentration at 0.0295 kg / m³ through continuous dosing. 3 Although the fourth phase (June 11-13) continued to operate at the third frequency for 36 hours, thanks to the system's delayed compensation mechanism after the water replenishment was completed, the final concentration recovered to 0.0303 kg / m³. 3 Throughout the entire experiment, the measured concentration of the corrosion inhibitor remained stable at 0.0295-0.0303 kg / m³ under all operating conditions. 3 Within the range of 29.5-30.3 mg / L, the fluctuation range was less than ±3%, which fully verified the control accuracy and reliability of the system in maintaining dynamic stability of the reagent concentration under different water replenishment conditions.

[0055] The above are merely preferred embodiments of the present invention and are not intended to limit the present 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. An automatic dosing system for an SCAL type intercooled system, characterized in that, include: A dosing system is provided, comprising a slow-release agent solution tank (101), a demineralized water tank (102), a slow-release agent solution tank level gauge (103), a slow-release agent dosing pipeline (110), and a replenishment demineralized water pipeline (111). The slow-release agent solution tank level gauge (103) is installed on the slow-release agent solution tank (101). One end of the slow-release agent dosing pipeline (110) is connected to the slow-release agent solution tank (101). A slow-release agent dosing metering pump (107) and a slow-release agent dosing flow meter (106) are sequentially provided on the slow-release agent dosing pipeline (110) along the water flow direction. One end of the replenishment demineralized water pipeline (111) is connected to the demineralized water tank (102). A demineralized water flow meter (109) and a demineralized water electric gate (108) are sequentially provided on the replenishment demineralized water pipeline (111) along the water flow direction. The control system includes a control device (202); the control device (202) is connected to the level gauge (103) of the slow-release agent solution tank, the flow meter (106) of the slow-release agent dosing, the flow meter (109) of the demineralized water, the metering pump (107) of the slow-release agent dosing, and the electric gate (108) of the demineralized water. An intercooling system is provided, comprising an intercooling tower (301), a condenser (303), and a bypass treatment loop. The outlet of the condenser (303) is connected to the inlet of the intercooling tower (301), and the outlet of the intercooling tower (301) is connected to the inlet of the condenser (303), forming a cooling water circulation loop. The inlet of the bypass treatment loop is connected to the outlet pipe of the condenser (303), and the outlet is connected to the inlet of the condenser (303). Water-side pipeline; a bypass flow meter (104) is provided on the bypass treatment circuit; the other end of the slow-release agent dosing pipeline (110) is connected between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser (303); the other end of the supplemental demineralized water pipeline (111) is connected between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser (303); the bypass flow meter (104) is signal-connected to the control device (202).

2. The SCAL-type intercooled system automatic dosing system according to claim 1, characterized in that, The bypass treatment circuit is provided with an iron remover (304), an activated carbon filter (305), and a mixed bed (306) in sequence along the water flow direction; the other end of the slow-release agent dosing pipeline (110) and the other end of the supplemental demineralized water pipeline (111) are both connected to the outlet side pipeline of the mixed bed (306).

3. The SCAL-type intercooled system automatic dosing system according to claim 1, characterized in that, Both the bypass flow meter (104) and the demineralized water flow meter (109) are time-difference ultrasonic flow meters.

4. The SCAL-type intercooled system automatic dosing system according to claim 1, characterized in that, The slow-release agent dosing pipeline (110) is also equipped with a slow-release agent dosing electric gate (105), which is located downstream of the water flow direction of the slow-release agent dosing flow meter (106) and is signal-connected to the control device (202).

5. The SCAL-type intercooled system automatic dosing system according to claim 4, characterized in that, The controlled-release dosing electric gate (105) is connected to the control device (202) via a fourth cable (206).

6. The SCAL-type intercooled system automatic dosing system according to claim 1, characterized in that, The cooling water circulation loop is provided with heat dissipation fins (302) between the intercooler (301) and the condenser (303) along the water flow direction. The inlet of the heat dissipation fins (302) is connected to the outlet of the intercooler (301), and the outlet of the heat dissipation fins (302) is connected to the inlet of the condenser (303).

7. The SCAL-type intercooled system automatic dosing system according to claim 1, characterized in that, The slow-release agent dosing flow meter (106) has a first preset length of straight pipe section on both the front and rear sides of the slow-release agent dosing pipeline (110); the demineralized water flow meter (109) has a second preset length of straight pipe section on both the front and rear sides of the supplementary demineralized water pipeline (111); and the bypass treatment flow meter (104) has a third preset length of straight pipe section on both the front and rear sides of the bypass treatment circuit.

8. The SCAL-type intercooled system automatic dosing system according to claim 1, characterized in that, The slow-release agent dosing flow meter (106) is connected to the control device (202) via a sixth cable (208); the demineralized water flow meter (109) is connected to the control device (202) via a fifth cable (207); the bypass flow meter (104) is connected to the control device (202) via a second cable (204); the slow-release agent solution tank level gauge (103) is connected to the control device (202) via an eighth cable (210); the slow-release agent dosing metering pump (107) is connected to the control device (202) via a seventh cable (209); and the demineralized water electric gate (108) is connected to the control device (202) via a third cable (205).

9. An automatic dosing method for a SCAL-type intercooling system, characterized in that, The system based on any one of claims 1 to 8 includes the following steps: The slow-release agent solution stored in the slow-release agent solution tank (101) is transported and added to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser (303) via the slow-release agent dosing pipeline (110), through the slow-release agent dosing metering pump (107) and the slow-release agent dosing flow meter (106); By supplementing the demineralized water pipeline (111), the demineralized water stored in the demineralized water tank (102) is transported and supplemented to the connecting pipeline between the outlet of the bypass treatment circuit and the inlet pipeline of the condenser (303) via the demineralized water flow meter (109) and the demineralized water electric gate (108); The level of the slow-release agent solution tank (101) is monitored by the level gauge (103) of the slow-release agent solution tank, the flow rate through the bypass treatment circuit is monitored by the bypass treatment flow meter (104), the flow rate of the added slow-release agent is monitored by the slow-release agent dosing flow meter (106), and the flow rate of the added demineralized water is monitored by the demineralized water flow meter (109). The control device (202) acquires the above monitoring data and generates control commands based on preset logic to control the operating frequency of the slow-release agent dosing pump (107) and the opening and closing of the demineralized water electric door (108); After the cooling water completes heat exchange in the condenser (303), it is transported to the intercooler tower (301) through the pipeline for cooling, and then returns to the condenser (303) to complete the circulation; at the same time, a portion of the cooling water is diverted from the outlet pipe of the condenser (303) into the bypass treatment circuit for treatment, and the treated water is returned to the inlet pipe of the condenser (303).

10. The automatic dosing method for a SCAL-type intercooling system according to claim 9, characterized in that, The control device (202) generates control commands based on preset logic to control the operating frequency of the sustained-release dosing pump (107), including: The first theoretical dosage is calculated when the bypass treatment is running only, using the following formula: in, This is the first theoretical dosage; Y is the flow rate value monitored by the bypass flow meter (104); Y is the target concentration of the slow-release agent set by the system. Density of the sustained-release agent; The second theoretical dosage is calculated when the bypass treatment and demineralized water replenishment are running simultaneously. The calculation formula is as follows: in, This is the second theoretical dosage; The flow rate value monitored by the demineralized water flow meter (109); The maximum output of the sustained-release agent metering pump (107) is set to M; When the demineralized water electric door (108) is closed, the controlled-release agent dosing pump (107) is controlled to dispense the agent according to the first theoretical dosage. It operates at the corresponding first frequency; When the demineralized water electric door (108) is opened, if If M ≤ M, then control the sustained-release agent dosing pump (107) to do the dosage according to the second theoretical dosage. The corresponding second frequency operation; if If M is selected, the controlled-release agent metering pump (107) is controlled to operate at the third frequency corresponding to M, and after the demineralized water electric door (108) closes, a delay is specified. Then switch the sustained-release dosing pump (107) to operate at the first frequency. The calculation formula is: Where T is the duration of the opening of the demineralized water electric door (108).

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