A boiler dosing system and a boiler

Abstract

The utility model relates to the field of boiler water treatment, concretely relates to a kind of boiler dosing system and boiler, wherein dosing system includes controller, dosing tank, phosphorus radical analyzer, calcium hardness analyzer and dosing pump, dosing tank: for storing medicament, and with boiler through dosing pipe intercommunication;Phosphorus radical analyzer: for detecting phosphorus radical content in boiler water;Calcium hardness analyzer: set in boiler water inlet side, for detecting the calcium hardness of boiler water;Dosing pump: set on the dosing pipe, between boiler and the dosing tank;Controller: respectively with phosphorus radical analyzer, calcium hardness analyzer and dosing pump electric connection.The utility model is connected phosphorus radical analyzer by setting lead-out pipe on boiler, real-time monitoring is carried out to phosphorus radical in boiler water, according to the real-time control dosing pump frequency of phosphorus radical variation situation, avoid the adjustment lag problem caused by artificial sampling, reduce boiler scale.

Description

Technical Field

[0001] This utility model relates to the field of boiler water treatment, and in particular to a boiler chemical dosing system and a boiler. Background Technology

[0002] In industrial sectors such as thermal power plants and chemical plants, boilers are core equipment, and their operational safety and economy are directly affected by water quality. To prevent scale and corrosion on boiler tube walls, demineralized water is commonly used as boiler feedwater, along with the addition of chemical agents (such as trisodium phosphate and ferrous phosphate) for water quality conditioning. The main function of these agents is to convert residual hardness components in the boiler water into easily removable sludge through chemical reactions, thereby effectively inhibiting scale formation.

[0003] Existing chemical dosing control methods primarily rely on manual, periodic monitoring and experience-based adjustments. Specifically, operators typically sample and test the phosphate content in the boiler water daily, then manually adjust the stroke or frequency of the dosing pump based on the test results to change the dosage. This intermittent, manually-driven dosing model suffers from significant lag and inaccuracy. Because boiler load, water quality, and evaporation rates are all dynamically changing, fixed dosing strategies cannot respond promptly to actual system needs, easily leading to deviations in dosage from the optimal range: insufficient dosing fails to completely eliminate scaling risks, threatening boiler safety; excessive dosing not only wastes chemicals but may also cause salt accumulation in the boiler water.

[0004] Therefore, existing technologies suffer from problems such as large fluctuations in boiler water quality and high operating costs due to low precision in chemical dosing control, and there is an urgent need for an improved solution that can achieve precise, automatic and continuous chemical dosing. Utility Model Content

[0005] The purpose of this invention is to overcome the technical problem in the existing technology of adjusting the dosing pump stroke by obtaining the phosphate content in the boiler water through daily testing, which results in insufficient or excessive dosing. This invention provides a boiler dosing system and a boiler.

[0006] In a first aspect, this utility model provides a boiler chemical dosing system, including a controller, a dosing tank, a phosphate analyzer, a calcium hardness analyzer, and a dosing pump. Chemical dosing tank: Used to store chemicals and connected to the boiler via a dosing pipe; Phosphate analyzer: used to detect the phosphate content in boiler water; Calcium hardness analyzer: installed on the boiler inlet side, used to detect the calcium hardness of the boiler inlet water; Dosing pump: installed on the dosing pipe, located between the boiler and the dosing tank; Controller: Electrically connected to the phosphate analyzer, calcium hardness analyzer, and dosing pump respectively.

[0007] This utility model discloses a boiler chemical dosing system. A phosphate analyzer monitors the phosphate content in boiler water in real time and feeds the data back to the controller. Simultaneously, a calcium hardness analyzer monitors the calcium hardness of the boiler inlet water in real time and feeds it back to the controller. Based on the received water quality data, the controller outputs a control signal to the dosing pump, adjusting its operating frequency in real time to dynamically control the dosing dosage. This system constructs a closed-loop automatic dosing control structure based on real-time water quality parameters, solving the problem of lag in manual testing and adjustment at the hardware level, and achieving accurate and timely dosing.

[0008] Preferably, the dosing pump is a frequency-adjustable metering pump.

[0009] Metering pumps are highly accurate and can linearly adjust the dosage by changing the frequency. They have a fast response speed and are key actuators for achieving precise and automatic dosing.

[0010] Preferably, it also includes a lead-out pipe for connecting to a boiler, and the phosphate analyzer is located at the end of the lead-out pipe away from the boiler.

[0011] This structure can utilize the boiler's existing sampling points without requiring large-scale modifications to the boiler itself. It is simple to construct, low in cost, and can obtain representative boiler water samples.

[0012] Preferably, it also includes a heat exchanger disposed between the boiler and the phosphate analyzer.

[0013] High boiler water temperature can affect the accuracy of the colorimetric reaction in the phosphate analyzer. Adding a heat exchanger can cool the water sample, ensuring that the analyzer operates at the optimal temperature, thereby significantly improving the detection accuracy of phosphate.

[0014] Preferably, it also includes a diversion pipe for connecting to the boiler's inlet pipe, and the calcium hardness analyzer is mounted on the diversion pipe.

[0015] The system uses a branch pipe to monitor the calcium hardness of the incoming water online. It has a simple structure, does not affect the main water supply, and can achieve real-time and continuous monitoring of the incoming water quality.

[0016] Preferably, the system further includes a display, which is electrically connected to the controller.

[0017] The monitor is located in the boiler's operating area. Through the monitor, operators can intuitively and in real time view key operating parameters such as phosphate concentration, calcium hardness, and dosing pump frequency, as well as system alarm information. This greatly facilitates on-site inspections and rapid understanding of system status, and improves the convenience of human-machine interaction.

[0018] Preferably, the controller is a distributed boiler control system or a programmable logic controller.

[0019] It adopts a mature and reliable control system with high integration, which facilitates data interaction and centralized management with other boiler control systems, enabling complex control algorithms and remote monitoring.

[0020] Preferably, the controller is equipped with a calculation module for calculating the initial dosing speed of the dosing pump based on the received signals of boiler inlet water flow, calcium hardness, and reagent concentration.

[0021] The hardware-integrated computing module enables automatic and rapid calculation of the initial dosage, reducing human intervention and calculation errors, and improving the system's automation level.

[0022] Preferably, the controller is equipped with a PID control module, which is used to calculate and output a control signal to the dosing pump in real time based on the deviation between the feedback signal from the phosphate analyzer and the set value, so as to adjust its frequency.

[0023] The PID control module is the core of achieving precise closed-loop control. It can dynamically fine-tune the dosage according to water quality fluctuations, so that the phosphate concentration is kept within the ideal range, effectively avoiding over- or under-dosing.

[0024] In a second aspect, the present invention provides a boiler, including a boiler body and a boiler dosing system as described above.

[0025] This utility model discloses a boiler that integrates the chemical dosing system with the boiler body, achieving fully automated monitoring and precise chemical dosing of boiler water. Specifically, the calcium hardness analyzer is preferably installed directly on the inlet pipe of the boiler body to achieve in-situ real-time monitoring of the inlet water quality; the phosphate analyzer is connected to the boiler body to directly sample and analyze the boiler water quality. This structural design enables the boiler to self-regulate and intelligently dosing based on the inlet water hardness and boiler water phosphate concentration, fundamentally improving the automation level and reliability of water quality control at the equipment level, and effectively eliminating the risk of scaling and chemical waste caused by untimely manual intervention.

[0026] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. This utility model provides a boiler dosing system, which connects a phosphate analyzer to an outlet pipe on the boiler to monitor phosphate in the boiler water in real time, and controls the dosing pump frequency in real time according to the changes in phosphate, avoiding the adjustment lag problem caused by manual sampling and reducing boiler scaling; 2. This utility model provides a boiler dosing system that calculates the initial dosing rate based on calcium hardness, boiler inlet water speed, and chemical concentration, effectively removing impurities from the water during the initial boiler operation. 3. This utility model provides a boiler chemical dosing system that uses calcium hardness, which is relatively easy to detect, as the calculation value. It ensures complete reaction by adding excessive amounts of chemicals, which simplifies the detection process and makes the data highly reliable, thereby improving the quality of boiler water treatment. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a boiler dosing system according to this utility model; Marked in the image: 1-Controller, 2-Dosing tank, 3-Phosphate analyzer, 4-Calcium hardness analyzer, 5-Dosing pump, 6-Dosing pipe, 7-Outlet pipe, 8-Heat exchanger, 9-Diverter pipe, 10-Display, 11-Boiler body, 12-Inlet water pipe. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to specific embodiments. However, it should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0029] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of this utility model is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the utility model solution or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on this utility model.

[0030] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0031] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0032] Furthermore, in the description of the embodiments of this utility model, "several", "multiple", and "several" represent at least two. The number can be any number, such as two, three, four, five, six, seven, eight, or nine, and can even exceed nine.

[0033] Furthermore, in the description of the technical solution of this utility model, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "equipped with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0034] Example 1 like Figure 1 As shown, a boiler chemical dosing system includes a controller 1, a dosing tank 2, a phosphate analyzer 3, a calcium hardness analyzer 4, and a dosing pump 5. Chemical dosing tank 2: Used to store chemicals and connected to the boiler via chemical dosing pipe 6; Phosphate Analyzer 3: Used to detect phosphate content in boiler water; Calcium hardness analyzer 4: Installed on the boiler inlet side, used to detect the calcium hardness of the boiler inlet water; Dosing pump 5: installed on the dosing pipe 6, located between the boiler and the dosing tank 2; Controller 1: Electrically connected to the phosphate analyzer 3, the calcium hardness analyzer 4 and the dosing pump 5 respectively, and used to receive detection data and control the operating frequency of the dosing pump 5.

[0035] In an optional implementation, the dosing pump 5 can be a frequency-adjustable metering pump. The metering pump has high accuracy, and the dosing amount can be linearly adjusted by changing the frequency. It has a fast response speed and is a key actuator for achieving precise automatic dosing.

[0036] In an optional embodiment, an outlet pipe 7 can be installed on the boiler. The outlet pipe 7 can be connected to the original sampling point of the boiler. The phosphate analyzer 3 is installed at the end of the outlet pipe 7 away from the boiler. This structure utilizes the original sampling point of the boiler, without the need for large-scale modification of the boiler body 11. It is simple to construct, low in cost, and can obtain representative boiler water samples.

[0037] In an optional implementation, a heat exchanger 8 can be installed on the outlet pipe 7 to cool the water sample, ensuring that the phosphate analyzer 3 operates at the optimal operating temperature, thereby significantly improving the detection accuracy of phosphate.

[0038] In an optional implementation, a branch pipe 9 can be installed at the boiler inlet pipe 12, and the calcium hardness analyzer 4 can be installed on the branch pipe 9. The calcium hardness of the inlet water can be monitored online through the branch pipe. The structure is simple, does not affect the main water supply, and can realize real-time and continuous monitoring of the inlet water quality.

[0039] In an optional implementation, a display 10 can be installed in the boiler's operating area. The display 10 is electrically connected to the controller 1. Through the display 10, operators can intuitively and in real time view key operating parameters such as phosphate concentration, calcium hardness, and dosing pump frequency, as well as system alarm information at the boiler site. This greatly facilitates on-site inspections and rapid understanding of system status, and improves the convenience of human-machine interaction.

[0040] In one or more embodiments, the controller 1 can be a distributed control system integrated with the boiler or a programmable logic controller 1. It adopts a mature and reliable control system with high integration, which facilitates data interaction and centralized management with other control systems of the boiler, and realizes complex control algorithms and remote monitoring.

[0041] In an optional implementation, a calculation module can be integrated on the controller 1 to calculate the initial dosing speed of the dosing pump 5 based on the received signals of boiler inlet water flow, calcium hardness, and reagent concentration. This enables automatic and rapid calculation of the initial dosing amount, reduces human intervention and calculation errors, and improves the system's automation level.

[0042] In an optional implementation, a PID control module can be configured on the controller 1 to calculate and output a control signal to the dosing pump 5 in real time based on the deviation between the feedback signal from the phosphate analyzer 3 and the set value, thereby adjusting its frequency. The PID control module is the core of achieving precise closed-loop control and can dynamically fine-tune the dosage according to water quality fluctuations, so that the phosphate concentration is stabilized within the ideal range, effectively avoiding over- or under-dosing.

[0043] Example 2 like Figure 1 As shown, this embodiment provides a boiler, including a boiler body 11, and also includes a boiler dosing system as described in Embodiment 1.

[0044] Example 3 like Figure 1 As shown in the embodiment, a boiler chemical dosing method is provided, including the following steps: S1. Add an outlet pipe 7 at the location of the manual sampling pipe for boiler water. The outlet pipe 7 is connected to the phosphate analyzer 3. Traditional manual sampling and testing has a lag and cannot reflect water quality changes in real time. By adding an outlet pipe 7 at the location of the manual sampling pipe and connecting it to the phosphate analyzer 3, real-time continuous monitoring of phosphate content can be achieved, providing a data basis for automatic adjustment. S2. Configure dosing tank 2 and test the concentration of the drug solution in dosing tank 2. Inconsistent concentrations when manually preparing drugs can lead to deviations in the calculation of the dosage. By configuring a standardized dosing tank 2 and accurately testing the concentration of the drug solution, the accuracy of the drug concentration can be ensured, providing reliable parameters for subsequent automatic calculations. S3. Add a calculation module to the boiler DCS (Distributed Control System) to automatically read the boiler water intake. Traditional manual recording of boiler water intake has errors and delays. By automatically reading the real-time water intake through the boiler DCS system, dynamic flow data can be obtained, eliminating errors from manual recording. S4. Calculate the feed rate of the dosing pump 5 according to the formula V=Q×ne / a. The dosing rate is automatically calculated by the formula to match the initial dosing amount with the influent flow rate. The calcium hardness, which is relatively easy to detect, is used as the calculation value. Overdosing is used to ensure complete reaction, which simplifies the detection process and makes the data reliable, thereby improving the quality of boiler water treatment. In the formula: V represents the feed rate of the dosing pump 5, in m³ / h; Q represents the boiler inlet water flow rate, m³ / h; e represents calcium hardness, in mg / L; a represents the concentration of the drug in the solution, in mg / L; n is the dosage ratio; S5. In the initial stage of boiler operation, the chemical is added according to the speed V. At the same time, the frequency of the chemical addition pump 5 is adjusted according to the monitoring data of the phosphate analyzer 3 and the changes in phosphate. The frequency of the chemical addition pump 5 is adjusted in real time according to the online detection data of phosphate, so as to achieve dynamic matching of chemical addition and water intake.

[0045] In one or more embodiments, 4≤n≤6, the calcium hardness and overdosing are used to ensure complete reaction. This multiple range can ensure sufficient neutralization of calcium and magnesium ions, avoiding scaling, while also avoiding overdosing which could lead to waste of reagents or phosphate hiding.

[0046] Taking actual use as an example: the boiler inlet water flow rate Q is 35 m3 / h, the calcium hardness e is 0.1 mg / L, the reagent concentration a is 3000 mg / L, the dosing ratio is 5, and the dosing rate at the beginning of boiler operation is calculated to be 0.0058 m3 / h according to the formula V=Q×ne / a.

[0047] In one or more embodiments, a phosphate control value can also be set. In step S5, when the phosphate level in the boiler water is lower than the control value, the frequency of the dosing pump 5 is increased; when the phosphate level in the boiler water is higher than the control value, the frequency of the dosing pump 5 is decreased. The rate of change of the frequency of the dosing pump 5 is controlled by the proportional coefficient P and the integral time T, and the formula is: OUT=P×k×( ) + current value; In the formula: OUT represents the output of dosing pump 5; The increase is the change in phosphate content; The current value is the current output of dosing pump 5; K is a constant, with a value of 0.5; P is 1.2-1.4; T is 1000-1200s.

[0048] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A boiler chemical dosing system, characterized in that, It includes a controller (1), a dosing tank (2), a phosphate analyzer (3), a calcium hardness analyzer (4), and a dosing pump (5). Dosing tank (2): Used to store chemicals and connected to the boiler via dosing pipe (6); Phosphate analyzer (3): used to detect the phosphate content in boiler water; Calcium hardness analyzer (4): set on the boiler inlet side, used to detect the calcium hardness of the boiler inlet water; Dosing pump (5): installed on the dosing pipe (6), located between the boiler and the dosing tank (2); Controller (1): Electrically connected to the phosphate analyzer (3), calcium hardness analyzer (4) and dosing pump (5) respectively.

2. The boiler dosing system according to claim 1, characterized in that, The dosing pump (5) is a frequency-adjustable metering pump.

3. A boiler dosing system according to claim 1, characterized in that, It also includes an outlet pipe (7) for connecting to the boiler, and the phosphate analyzer (3) is located at the end of the outlet pipe (7) away from the boiler.

4. A boiler dosing system according to claim 1, characterized in that, It also includes a heat exchanger (8) disposed between the boiler and the phosphate analyzer (3).

5. A boiler dosing system according to claim 1, characterized in that, It also includes a diversion pipe (9) for connecting the boiler inlet pipe (12), and the calcium hardness analyzer (4) is installed on the diversion pipe (9).

6. A boiler dosing system according to claim 1, characterized in that, It also includes a display (10) which is electrically connected to the controller (1).

7. A boiler dosing system according to any one of claims 1-6, characterized in that, The controller (1) is a boiler distributed control system or a programmable logic controller.

8. A boiler dosing system according to claim 7, characterized in that, The controller (1) is equipped with a calculation module, which is used to calculate the initial dosing speed of the dosing pump (5) based on the received signals of boiler water flow, calcium hardness and reagent concentration.

9. A boiler dosing system according to claim 7, characterized in that, The controller (1) is equipped with a PID control module, which is used to calculate and output a control signal to the dosing pump (5) in real time based on the deviation between the feedback signal of the phosphate analyzer (3) and the set value, and adjust its frequency.

10. A boiler, comprising a boiler body (11), and further comprising a boiler dosing system as described in any one of claims 1-9.

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