Novel gas-fired hot water boiler cleaning system

Abstract

The utility model provides a novel gas-fired hot water boiler cleaning system which comprises a cleaning water tank, a cleaning circulating pump, a Roots blower and other components, related pipelines and valves, an electric heating device, a PLC (Programmable Logic Controller) and the like. The top of the cleaning water tank is communicated with a demineralized water inlet pipeline, the bottom is connected with the cleaning circulating pump, the compressed air buffer tank is connected with the Roots blower, the gas-water mixer is connected with related parts, and a water outlet of the hot water boiler is connected with the cleaning water tank. Precise control and monitoring are achieved through the PLC, gas and water are mixed to form a slug flow to efficiently remove impurities in the boiler, the application range is wide, cleaning modes are flexible and diversified, cleaning parameters are digitally controlled, and maintenance and emission are easy and convenient. Compared with the prior art, the device has the beneficial effects of precise control, efficient descaling, wide application, various modes, parameter optimization, convenience in maintenance and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of equipment cleaning, and in particular to a novel gas hot water boiler cleaning system. Background Art

[0002] During the heating season, due to the direct entry of the circulating water of the heating network into the hot water boiler body, the softening treatment of the circulating water of the heating network is not in place and the boiler has been running for a long time, at the end of the heating season, scale, residue and impurities will inevitably form in the heating parts of the boiler such as the boiler convection tube bundle, upper and lower drums, and upper and lower tube bundles. The fundamental reason for the formation of scale in the boiler is the rust caused by improper maintenance of the heating pipe network and the large amount of calcium and magnesium ions in the feed water. After continuous heating and concentration under high temperature and high pressure of the boiler, a series of chemical and physical reactions occur on the heating surface of the furnace, and finally dense and hard scale is attached to the heating surface of the boiler, which greatly reduces the heat transfer effect of the boiler, and even seriously causes the boiler tube to burst, affecting the stable operation of the boiler, so it is necessary to regularly inspect and clean the inside of the boiler.

[0003] At present, there are generally two ways to clean the inside of a boiler: one is physical descaling, that is, the boiler is shut down, drained and cooled, and then people manually enter the boiler drum to use flat shovels, wire brushes, motorized pipe milling machines and other equipment to descale the scale attached to the boiler; the other is chemical descaling, that is, using hydrochloric acid or nitric acid to dissolve the boiler to descale the inner wall of the boiler.

[0004] However, at present, the boiler descaling methods are relatively simple. The physical descaling method is particularly dependent on manual experience. If too much force is used, it will cause damage to the inner wall of the boiler and the boiler is not easy to operate in a small enclosed space. The chemical descaling method uses the pickling method to pickle the scale. Some scale is still adsorbed on the surface of the inner wall of the boiler, and there is a problem of not being able to rinse it clean. Utility Model Content

[0005] The utility model aims to provide a gas hot water boiler cleaning system, which is independent of manual experience, easy to operate and can clean scales to solve the above problems.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A novel gas hot water boiler cleaning system comprises a cleaning water tank (1), a PLC controller (3), a cleaning circulation pump (4), a Roots blower (7), a plurality of electric valves, a plurality of manual valves and pipelines, and is characterized in that it also comprises an electric heating device (2), a gas-water mixer (5), a compressed air buffer tank (6) and a pipeline flow meter (8);

[0008] The top of the cleaning water tank (1) is connected to a demineralized water inlet pipe, and the bottom of the cleaning water tank (1) is connected to a cleaning circulation pump (4) through a pipe;

[0009] One side of the compressed air buffer tank (6) is connected to a Roots blower (7) via a pipeline, and the other side of the compressed air buffer tank (6) is connected to an outlet pipeline;

[0010] The gas-water mixer (5) is provided with an air inlet and a water inlet at one end, and a high-pressure fluid outlet at the other end. The air inlet is connected to the outlet pipe at the top of the compressed air buffer tank (6), and a check valve is provided in the middle; the water inlet is connected to the outlet pipe of the cleaning circulation pump, and the outlet of the gas-water mixer is respectively connected to the water inlet of the economizer and the water inlet of the energy saver at the bottom of the hot water boiler;

[0011] A water outlet is provided on the side of the hot water boiler, and the water outlet is connected to the cleaning water tank (1) through a pipeline.

[0012] The desalted water inlet pipe is equipped with a desalted water inlet manual door (AY1); the front and rear pipes of the cleaning circulation pump are respectively equipped with a washing water tank outlet electric door (AV1) and a cleaning circulation pump outlet electric door (AV2).

[0013] The Roots blower (7) outlet air duct is provided with a Roots blower outlet manual door (AY2), and the compressed air buffer tank (6) outlet duct is provided with a compressed air buffer tank outlet electric door (AV3).

[0014] The pipes leading to the left and right ends of the water side of the economizer are respectively installed with an economizer water inlet manual door (AY3) and an energy saver water inlet manual door (AY4); the side water outlet of the hot water boiler is installed with a boiler water discharge manual door (AY5) through a pipe.

[0015] The cleaning water tank (1) is provided with a PLC controller (3), and the PLC controller (3) is connected to a pipeline flow meter (8) and a cleaning circulation pump (4) via signals.

[0016] A pipeline flow meter (8) is installed in the pipeline between the cleaning circulation pump (4) and the air-water mixer (5), and the flow signal of the pipeline flow meter (8) is transmitted to the PLC controller (3).

[0017] The cleaning water tank (1) is provided with an electric heating device (2) at the side end, and a cleaning water tank drain valve (AY7) is provided at the bottom.

[0018] The electric valves are all connected to the PLC controller (3) by signal.

[0019] The gas hot water boiler cleaning system is also suitable for small coal-fired boilers.

[0020] The compressed air buffer tank (6) is provided with a safety valve at the top, and is connected to a condensate drain outlet at the bottom via a pipeline, and the pipeline is provided with a condensate outlet manual valve (AY6).

[0021] The specific operation is as follows: before cleaning, first ensure that all manual doors are closed, the electric valves are in the initial position, and the electric heating device (2), PLC controller (3), cleaning circulation pump (4), Roots blower (7) and other equipment are in normal standby state. When cleaning begins, open the desalted water inlet manual door (AY1) to allow desalted water to enter the cleaning water tank (1). Observe the liquid level and close the water inlet manual door (AY1) when the appropriate water level is reached. Start the electric heating device (2) to adjust the water temperature or solution in the water tank to the predetermined temperature. Subsequently, the cleaning circulation pump (4) is started by the PLC controller (3), and the PLC controller reads the value of the pipeline flow meter (8), adjusts the water flow rate to above 5 m / s, opens the electric door (AV1) at the outlet of the washing water tank and the electric door (AV2) at the outlet of the washing circulation pump, and opens the electric door (AV3) at the outlet of the compressed air buffer tank and the manual door (AY2) at the outlet of the roots blower at the same time, so that the compressed air enters the buffer tank (6) and mixes with the water from the cleaning circulation pump (4) in the air-water mixer (5), so that a spring-like flow can be formed in stages, which can effectively stir the boiler water and more effectively remove boiler impurities. The mixed high-pressure fluid enters the boiler through the three-way pipe through the economizer water inlet manual door (AY3) and the economizer water inlet manual door (AY4), respectively, to clean the boiler. The cleaned water flows back to the cleaning water tank (1) from the outlet on the side of the hot water boiler through the boiler water discharge manual door (AY5), completing a cleaning cycle. When the solution in the cleaning water tank (1) needs to be replaced or discharged, the cleaning water tank drain valve (AY6) is opened for processing. If the degree of scaling reaches or exceeds the pickling standard of GB / T 34355-2017, it is necessary to adopt alkaline cleaning, pickling, rinsing or passivation treatment. The process is the same as that of not reaching the pickling standard. It only needs to heat the liquid in the cleaning water tank (1), add chemicals to adjust the pH value of the liquid in the cleaning water tank (1), and the cleaning process does not require air-water mixing. When alkaline cleaning, it is necessary to start the electric heating device (2) to heat the liquid in the cleaning water tank to 60-70°C, and then add alkaline solution. When the water circulation temperature is higher than 80°C and the alkaline solution concentration meets the requirements, adjust the system flow, continue to circulate for 8-10 hours, stop heating, stop the cleaning circulation pump (4), and release the alkaline cleaning solution in the system; when pickling, in order to ensure a better pickling effect, the acid flow rate should be greater than 0.3m / s. The pickling system keeps circulating. When the water temperature reaches 40°C, corrosion inhibitor is added and the circulation ends when the iron ion no longer increases. When rinsing, when citric acid is used, ammonia is used to adjust the pH value to within the range of 3.5 to 4.0. The temperature of the pickling solution is maintained at about 90°C and the circulation ends when the iron ion is saturated. When passivating, 1.5% to 2% sodium nitrite solution is added with ammonia water to adjust the pH value to 10 to 10.5. Passivate at 60 to 90°C for 3 to 4 hours and then discharge the waste liquid. During the entire cleaning process, the liquid level, pH value and other parameters of the cleaning water tank (1) are monitored at any time through the PLC controller (3) to ensure the safety, effectiveness and stability of the cleaning operation.

[0022] Compared with the prior art, the beneficial effects of the utility model are:

[0023] Precise control and monitoring: The PLC controller can realize precise control of the start and stop of the cleaning circulation pump and the electric door switch to ensure the safety and effectiveness of the cleaning operation.

[0024] Efficient descaling: The mixture of air and water forms a slug-like flow, which can more effectively stir the boiler water, remove impurities in the boiler, and improve cleaning efficiency and quality.

[0025] Wide scope of application: Not only suitable for gas hot water boilers, but also suitable for small coal-fired boilers, with a wide range of applicability.

[0026] Flexible and diverse cleaning methods: You can choose alkaline cleaning, acid cleaning, rinsing and water washing according to the degree of scaling and actual needs to meet different cleaning requirements.

[0027] Optimized cleaning parameter control: During alkaline cleaning, acid cleaning, rinsing and other processes, parameters such as temperature, flow rate, liquid concentration and pH value are strictly controlled to ensure cleaning effect while reducing damage to equipment.

[0028] Convenient maintenance and discharge: When the solution in the cleaning water tank needs to be replaced or discharged, it can be conveniently handled through the cleaning water tank drain valve, which is easy to maintain and service the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The utility model is a series diagram of a novel gas hot water boiler cleaning system.

[0030] Markings in the figure: 1. Cleaning water tank; 2. Electric heating device; 3. PLC controller; 4. Cleaning circulation pump; 5. Air-water mixer; 6. Compressed air buffer tank; 7. Roots blower; 8. Pipeline flow meter; AV1, cleaning water tank outlet electric door; AV2, cleaning circulation pump outlet electric door; AV3, compressed air buffer tank outlet electric door; AY1, demineralized water inlet manual door; AY2, Roots blower outlet manual door; AY3, economizer water inlet manual door; AY4, economizer water inlet manual door; AY5, boiler drain manual door; AY6, cleaning water tank drain valve; AY7, condensate outlet manual valve. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be fully described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0032] As shown in the figure, a novel gas hot water boiler cleaning system comprises a cleaning water tank (1), a PLC controller (3), a cleaning circulation pump (4), a Roots blower (7), a plurality of electric valves, a plurality of manual valves and pipelines, and is characterized in that it also comprises an electric heating device (2), a gas-water mixer (5), a compressed air buffer tank (6), and a pipeline flow meter (8);

[0033] The top of the cleaning water tank (1) is connected to a demineralized water inlet pipe, and the bottom of the cleaning water tank (1) is connected to a cleaning circulation pump (4) through a pipe;

[0034] One side of the compressed air buffer tank (6) is connected to a Roots blower (7) via a pipeline, and the other side of the compressed air buffer tank (6) is connected to an outlet pipeline;

[0035] The gas-water mixer (5) is provided with an air inlet and a water inlet at one end, and a high-pressure fluid outlet at the other end, the air inlet being connected to the outlet pipe at the top of the compressed air buffer tank (6); the water inlet being connected to the outlet pipe of the cleaning circulation pump, and the high-pressure fluid outlet being connected to the economizer and energy saver at the bottom of the hot water boiler respectively through a three-way pipe;

[0036] A water outlet is provided on the side of the hot water boiler, and the water outlet is connected to the cleaning water tank (1) through a pipeline.

[0037] The desalted water inlet pipe is equipped with a desalted water inlet manual door (AY1); the front and rear pipes of the cleaning circulation pump are respectively equipped with a washing water tank outlet electric door (AV1) and a cleaning circulation pump outlet electric door (AV2).

[0038] The Roots blower (7) outlet air duct is provided with a Roots blower outlet manual door (AY2), and the compressed air buffer tank (6) outlet duct is provided with a compressed air buffer tank outlet electric door (AV3).

[0039] The pipes leading to the left and right ends of the water side of the economizer are respectively installed with an economizer water inlet manual door (AY3) and an energy saver water inlet manual door (AY4); the side water outlet of the hot water boiler is installed with a boiler water discharge manual door (AY5) through a pipe.

[0040] The cleaning water tank (1) is provided with a PLC controller (3), and the PLC controller (3) is connected to a pipeline flow meter (8) and a cleaning circulation pump (4) via signals.

[0041] A pipeline flow meter (8) is installed in the pipeline between the cleaning circulation pump (4) and the air-water mixer (5), and the flow signal of the pipeline flow meter (8) is transmitted to the PLC controller (3).

[0042] The cleaning water tank (1) is provided with an electric heating device (2) at the side end, and a cleaning water tank drain valve (AY6) is provided at the bottom.

[0043] The electric valves are all connected to the PLC controller (3) by signal.

[0044] The gas hot water boiler cleaning system is also suitable for small coal-fired boilers.

[0045] The compressed air buffer tank (6) is provided with a safety valve at the top, and is connected to a condensate drain outlet at the bottom via a pipeline, and the pipeline is provided with a condensate outlet manual valve (AY7).

[0046] The specific operation is as follows: before cleaning, first ensure that all manual doors are closed, the electric valves are in the initial position, and the electric heating device (2), PLC controller (3), cleaning circulation pump (4), Roots blower (7) and other equipment are in normal standby state. When cleaning begins, open the desalted water inlet manual door (AY1) to allow desalted water to enter the cleaning water tank (1). Observe the liquid level and close the water inlet manual door (AY1) when the appropriate water level is reached. Start the electric heating device (2) to adjust the water temperature or solution in the water tank to the predetermined temperature. Subsequently, the cleaning circulation pump (4) is started through the PLC controller (3), and the PLC controller reads the value of the pipeline flow meter (8), adjusts the water flow rate to above 5m / s, opens the electric door (AV1) at the outlet of the cleaning water tank and the electric door (AV2) at the outlet of the cleaning circulation pump, and opens the electric door (AV3) at the outlet of the compressed air buffer tank and the manual door (AY2) at the outlet of the roots blower at the same time, so that the compressed air enters the buffer tank (6) and mixes with the water from the cleaning circulation pump (4) in the air-water mixer (5), so that the elastic flow can be formed in stages, which can effectively stir the boiler water and more effectively remove the boiler impurities. The mixed high-pressure fluid enters the boiler through the three-way pipe through the economizer water inlet manual door (AY3) and the economizer water inlet manual door (AY4), and cleans the boiler. The cleaned water flows back to the cleaning water tank (1) from the outlet on the side of the hot water boiler through the boiler water discharge manual door (AY5), completing a cleaning cycle. When the solution in the cleaning water tank (1) needs to be replaced or discharged, open the cleaning water tank drain valve (AY6) for treatment; if the scaling degree reaches or exceeds the pickling standard of GB / T 34355-2017, it is necessary to adopt alkaline cleaning, pickling, rinsing or passivation treatment. The process is the same as that of not reaching the pickling standard, only the liquid in the cleaning water tank (1) needs to be heated, and the pH value of the liquid in the cleaning water tank (1) needs to be adjusted by adding chemicals, and the cleaning process does not need to be mixed with air and water. When alkaline washing, it is necessary to start the electric heating device (2) to heat the cleaning water tank liquid to 60-70°C, and then add alkaline solution. When the water circulation temperature is higher than 80°C and the alkaline solution concentration meets the requirements, adjust the system flow, continue to circulate for 8-10 hours, stop heating, stop the cleaning circulation pump (4), and release the alkaline cleaning solution in the system; when pickling, in order to ensure a better pickling effect, the acid flow rate should be greater than 0.3m / s. The pickling system keeps circulating. When the water temperature reaches 40°C, corrosion inhibitor is added and the circulation ends when the iron ion no longer increases. When rinsing, when citric acid is used, ammonia is used to adjust the pH value to within the range of 3.5 to 4.0. The temperature of the pickling solution is maintained at about 90°C and the circulation ends when the iron ion is saturated. When passivating, 1.5% to 2% sodium nitrite solution is added with ammonia water to adjust the pH value to 10 to 10.5. Passivate at 60 to 90°C for 3 to 4 hours and then discharge the waste liquid. During the entire cleaning process, the liquid level, pH value and other parameters of the cleaning water tank (1) are monitored at any time through the PLC controller (3) to ensure the safety, effectiveness and stability of the cleaning operation.

Claims

1. A new type of gas hot water boiler cleaning system, comprising a cleaning water tank (1), a PLC controller (3), a cleaning circulation pump (4), a Roots blower (7), a plurality of electric valves, a plurality of manual valves and pipelines, characterized in that It also includes an electric heating device (2), an air-water mixer (5), a compressed air buffer tank (6), and a pipeline flow meter (8); The top of the cleaning water tank (1) is connected to a demineralized water inlet pipe, and the bottom of the cleaning water tank (1) is connected to a cleaning circulation pump (4) through a pipe; One side of the compressed air buffer tank (6) is connected to a Roots blower (7) via a pipeline, and the other side of the compressed air buffer tank (6) is connected to an outlet pipeline; The gas-water mixer (5) is provided with an air inlet and a water inlet at one end, and a high-pressure fluid outlet at the other end, the air inlet being connected to an outlet pipe in the middle and upper part of a compressed air buffer tank (6); the water inlet being connected to an outlet pipe of a cleaning circulation pump, and the high-pressure fluid outlet being connected to an economizer and an energy saver at the bottom of a hot water boiler respectively through a three-way pipe; A water outlet is provided on the side of the hot water boiler, and the water outlet is connected to the cleaning water tank (1) through a pipeline.

2. A new type of gas hot water boiler cleaning system according to claim 1, characterized in that: The desalted water inlet pipe is equipped with a desalted water inlet manual door (AY1); the front and rear pipes of the cleaning circulation pump are respectively equipped with a washing water tank outlet electric door (AV1) and a cleaning circulation pump outlet electric door (AV2).

3. A new type of gas hot water boiler cleaning system according to claim 1, characterized in that: The Roots blower (7) outlet air duct is provided with a Roots blower outlet manual door (AY2), and the compressed air buffer tank (6) outlet duct is provided with a compressed air buffer tank outlet electric door (AV3).

4. A novel gas hot water boiler cleaning system according to claim 1, characterized in that: The pipes leading to the left and right ends of the water side of the economizer are respectively installed with an economizer water inlet manual door (AY3) and an energy saver water inlet manual door (AY4); the side water outlet of the hot water boiler is installed with a boiler water discharge manual door (AY5) through a pipe.

5. A novel gas hot water boiler cleaning system according to claim 1, characterized in that: The cleaning water tank (1) is provided with a PLC controller (3), and the PLC controller (3) is connected to a pipeline flow meter (8) and a cleaning circulation pump (4) via signals.

6. A novel gas hot water boiler cleaning system according to claim 1, characterized in that: A pipeline flow meter (8) is installed in the pipeline between the cleaning circulation pump (4) and the air-water mixer (5), and the flow signal of the pipeline flow meter (8) is transmitted to the PLC controller (3).

7. A novel gas hot water boiler cleaning system according to claim 1, characterized in that: The cleaning water tank (1) is provided with an electric heating device (2) at the side end, and a cleaning water tank drain valve (AY6) is provided at the bottom.

8. A novel gas hot water boiler cleaning system according to claim 1, characterized in that: The electric valves are all connected to the PLC controller (3) by signal.

9. A novel gas hot water boiler cleaning system according to claim 1, characterized in that: The gas hot water boiler cleaning system is also suitable for small coal-fired boilers.

10. A novel gas hot water boiler cleaning system according to claim 1, characterized in that: The compressed air buffer tank (6) is provided with a safety valve at the top, and is connected to a condensate drain outlet at the bottom via a pipeline, and the pipeline is provided with a condensate outlet manual valve (AY7).

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