Thermal deoxidizing and energy-saving system of boiler

Abstract

The utility model discloses a thermal deoxidizing and energy-saving system for a boiler. The thermal deoxidizing and energy-saving system comprises a water softener, the boiler, a deaerator, a first heat exchanger, a second heat exchanger and a third heat exchanger, the water softener is used for softening water, the output end of the water softener communicates with the first heat exchanger, the output end of the first heat exchanger communicates with a heat exchange water tank, and the output end of the heat exchange water tank communicates with the input end of the deaerator; the boiler is provided with a steam output pipe, a smoke exhaust pipe and a blow-off pipe, the boiler is used for generating steam, the smoke exhaust pipe is used for discharging smoke of the boiler, and the blow-off pipe is used for discharging sewage in the boiler; the output end of the deaerator, the second heat exchanger, the third heat exchanger and the boiler are sequentially communicated, the second heat exchanger is arranged in the heat exchange water tank, and the third heat exchanger is arranged in the smoke exhaust pipe; a first water pump is arranged between the second heat exchanger and the third heat exchanger. The thermal deoxidizing and energy-saving system of the boiler can reduce steam consumption and improve heat efficiency.

Description

Boiler thermal deaeration energy saving system Technical Field

[0001] This utility model relates to the field of boiler technology, and in particular to a boiler thermal deaeration and energy-saving system. Background Technology

[0002] In related technologies, boilers are usually equipped with deaeration systems to remove dissolved oxygen in water in order to reduce oxygen corrosion of boilers and pipes. The existing deaeration method is to store softened water in a deaerator, generate high-temperature steam in the boiler and pass it into the deaerator, so that the water in the deaerator boils slightly to release dissolved oxygen. However, this method consumes a lot of steam and has low overall thermal efficiency, which is not conducive to energy conservation and emission reduction. Summary of the Invention

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a boiler thermal deaeration and energy-saving system that can reduce steam consumption, improve thermal efficiency, reduce cavitation in the boiler feedwater pump, improve its operational reliability, and ensure the normal water level and safe operation of the boiler.

[0004] According to a first aspect of this utility model, a boiler thermal deaeration energy-saving system includes a water softener, a boiler, a deaerator, a first heat exchanger, a second heat exchanger, and a third heat exchanger. The water softener is used to soften water, and its output end is connected to the first heat exchanger. The output end of the first heat exchanger is connected to a hot water exchange tank, and the output end of the hot water exchange tank is connected to the input end of the deaerator. The boiler is equipped with a steam output pipe, a flue pipe, and a wastewater discharge pipe. The boiler generates steam, which is output to the deaerator through the steam output pipe. The flue pipe discharges the boiler's flue gas, and the wastewater discharge pipe discharges wastewater from the boiler. The output end of the wastewater discharge pipe faces the first heat exchanger. The output end of the deaerator, the second heat exchanger, the third heat exchanger, and the boiler are sequentially connected. The second heat exchanger is arranged in the hot water exchange tank, and the third heat exchanger is arranged in the flue pipe. A first water pump is provided between the second and third heat exchangers, and the first water pump drives water to flow from the second heat exchanger into the third heat exchanger.

[0005] The boiler thermal deaeration energy-saving system according to this utility model embodiment has at least the following beneficial effects: Water is input into a water softener, which softens the water, and then input into a first heat exchanger. Wastewater in the boiler is output through a drain pipe, with the output end of the drain pipe facing the first heat exchanger, so that the softened water can absorb heat from the wastewater through the first heat exchanger, thus initially raising the water temperature. Then, the water enters a hot water exchange tank, the outlet of which is connected to the input end of the deaerator, allowing the water to enter the deaerator. The boiler is equipped with a steam output pipe and a flue pipe. The steam output pipe is connected to the deaerator, allowing the steam generated by the boiler to be input into the deaerator, thereby heating the water in the deaerator to remove dissolved oxygen. Then, the water in the deaerator flows sequentially into a second heat exchanger, a first water pump, a third heat exchanger, and the boiler. The first water pump drives the water from the second heat exchanger into the third heat exchanger, and then into the boiler, so that the water can be reheated by the boiler to generate steam. By placing a second heat exchanger inside the water exchange tank, the water output from the water softener can absorb the heat from the deoxygenated water, thereby raising the temperature of the water entering the deaerator again and reducing the steam required for heating the water for deoxygenation. Furthermore, it lowers the temperature of the deoxygenated boiling water, reducing the inlet temperature of the first water pump, minimizing cavitation, ensuring the reliability of the first water pump, and extending its service life. Additionally, the third heat exchanger is located inside the flue gas pipe, allowing the deoxygenated water to absorb waste heat from the boiler's flue gas. This reduces heat loss, raises the temperature of the water entering the boiler, lowers the energy consumption for steam generation, and improves the boiler's thermal efficiency.

[0006] According to some embodiments of the present invention, the boiler is further provided with a sewage expansion container, the output end of the sewage pipe is connected to the sewage expansion container, the sewage expansion container is used to contain the sewage, and the first heat exchanger is arranged inside the sewage expansion container.

[0007] According to some embodiments of the present invention, a second water pump is provided between the hot water exchange tank and the deaerator, and the second water pump is used to drive water from the hot water exchange tank into the deaerator.

[0008] According to some embodiments of the present invention, the steam output pipe is provided with multiple output units, and the multiple output units are arranged at intervals within the deaerator.

[0009] According to some embodiments of the present invention, the input end and output end of the hot water exchange tank are respectively arranged at the upper and lower ends of the hot water exchange tank.

[0010] According to some embodiments of the present invention, an energy-saving device is provided at the end of the flue pipe near the boiler, the cross-sectional area of ​​the energy-saving device is larger than the cross-sectional area of ​​the flue pipe, and the third heat exchanger is arranged inside the energy-saving device.

[0011] According to some embodiments of the present invention, the energy saver is connected to a drain valve, which is arranged at the lower end of the energy saver and is used to discharge condensate.

[0012] According to some embodiments of this utility model, the inner bottom wall of the energy-saving device is arranged at an angle to guide the condensate to flow towards the drain valve.

[0013] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0015] Figure 1 is a schematic diagram of the boiler thermal deaeration and energy-saving system according to an embodiment of the present utility model;

[0016] Figure 2 is a schematic diagram of a boiler deaeration system in the prior art.

[0017] Figure label:

[0018] Water softener 100, hot water tank replacement 110;

[0019] Boiler 200, steam output pipe 210, output unit 211, flue pipe 220, economizer 221, drain valve 222, sewage pipe 230, sewage expansion container 240;

[0020] Deaerator 300, first heat exchanger 400, second heat exchanger 500, third heat exchanger 600, first water pump 700, second water pump 800. Detailed Implementation

[0021] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0022] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0023] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0024] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0025] Referring to Figure 2, in the related technology, the deaeration system of boiler 200 mainly softens water through water softener 100 and inputs it into deaerator 300. At the same time, boiler 200 generates steam and enters deaerator 300 to heat the water to a slight boil, thereby releasing dissolved oxygen in the water. The deaerated water is then input into boiler 200 to be heated to generate steam, and some of the steam continues to enter deaerator 300. However, the water temperature output by water softener 100 is relatively low, and the water takes a long time to heat in deaerator 300, resulting in a large amount of steam consumption. This leads to low thermal efficiency of boiler 200, which is not conducive to energy saving. Furthermore, a first water pump 700 is installed between deaerator 300 and boiler 200. The temperature of the deaerated water output by deaerator 300 is relatively high, which makes the first water pump 700 prone to cavitation. This causes a decrease in pump performance, an increase in noise and vibration, and erosion and corrosion of flow-through components, reducing service life and affecting the reliability of water supply to boiler 200.

[0026] As can be understood, referring to Figure 1, the boiler thermal deaeration energy-saving system of this utility model includes a water softener 100, a boiler 200, a deaerator 300, a first heat exchanger 400, a second heat exchanger 500, and a third heat exchanger 600. The water softener 100 is used to soften water, and its output end is connected to the first heat exchanger 400. The output end of the first heat exchanger 400 is connected to a hot water exchange tank 110, and the output end of the hot water exchange tank 110 is connected to the input end of the deaerator 300. The boiler 200 is equipped with a steam output pipe 210, a flue pipe 220, and a drain pipe 230. The boiler 200 is used to generate steam, which is sent to the deaerator through the steam output pipe 210. The boiler 200 has an output, and the exhaust pipe 220 is used to discharge the flue gas from the boiler 200. The sewage pipe 230 is used to discharge the sewage from the boiler 200, and the output end of the sewage pipe 230 is arranged towards the first heat exchanger 400. The output end of the deaerator 300, the second heat exchanger 500, the third heat exchanger 600 and the boiler 200 are connected in sequence. The second heat exchanger 500 is arranged in the hot water tank 110, and the third heat exchanger 600 is arranged in the exhaust pipe 220. A first water pump 700 is provided between the second heat exchanger 500 and the third heat exchanger 600. The first water pump 700 is used to drive water from the second heat exchanger 500 to the third heat exchanger 600.

[0027] Water is fed into the water softener 100, which softens the water, and then fed into the first heat exchanger 400. Wastewater from the boiler 200 is discharged through the drain pipe 230, with the outlet of the drain pipe 230 facing the first heat exchanger 400, so that the softened water can absorb heat from the wastewater and be initially heated. Then the water enters the hot water exchange tank 110, which is connected to the inlet of the deaerator 300, allowing the water to enter the deaerator 300. The boiler 200 is equipped with a steam output pipe 210 and a flue pipe 220. The steam output pipe 210 is connected to the deaerator 300, so that the steam generated by the boiler 200 can be input into the deaerator 300, thereby further heating the water in the deaerator 300 to a slight boil to remove dissolved oxygen from the water. Then, the deaerated water in the deaerator 300 flows sequentially into the second heat exchanger 500, the first water pump 700, the third heat exchanger 600 and the boiler 200, so that the water can be reheated by the boiler 200 to generate steam. By arranging a second heat exchanger 500 inside the water exchange tank 110, the water output from the softener 100 can absorb the heat from the deoxygenated water, thereby raising the temperature of the water entering the deaerator 300 and reducing the steam required for deoxygenating the heated water. Furthermore, it lowers the temperature of the deoxygenated boiling water, reducing the inlet water temperature of the first water pump 700, minimizing cavitation, ensuring the reliability of the first water pump 700, and extending its service life. Additionally, the third heat exchanger 600 is arranged inside the flue gas pipe 220, allowing the deoxygenated water to absorb the waste heat from the flue gas emitted by the boiler 200. This reduces flue gas heat loss, raises the temperature of the water entering the boiler 200, lowers the energy consumption for steam generation in the boiler 200, and improves the thermal efficiency of the boiler 200.

[0028] It should be noted that the water softener 100 softens water. By connecting the output of the water softener 100 to the first heat exchanger 400 and the hot water tank 110 in sequence, the water can absorb the heat from the wastewater discharged from the boiler 200 and the heat from the water output from the deaerator 300. This increases the temperature of the water entering the deaerator 300, reduces the heat required to heat the water, and lowers steam consumption. Furthermore, the water output from the second heat exchanger 500 can be pumped to the third heat exchanger 600 by the first water pump 700, allowing the water to absorb the heat from the flue gas discharged from the boiler 200. This not only reduces the fuel required for the boiler 200 to heat the water and improves the thermal efficiency of the boiler 200, but also lowers the temperature of the flue gas and reduces thermal pollution to the environment.

[0029] In addition, by setting up a hot water exchange tank 110 between the water softener 100 and the deaerator 300, the flow fluctuation entering the deaerator 300 can be reduced. This not only prolongs the contact time between the water and the second heat exchanger 500 and improves the efficiency of heat exchange, but also keeps the flow rate entering the deaerator 300 constant, which facilitates stable deoxygenation of the water by the deaerator 300 and improves the energy-saving effect and stability of deoxygenation.

[0030] The boiler 200 heats water and generates steam. During water heating, dissolved impurities gradually precipitate to form scale. A drain pipe 230 removes the scale suspended and deposited in the boiler 200, preventing it from adhering to the inner surface and reducing its heat transfer efficiency, as well as preventing pipe bursts due to blockage. Because the wastewater discharged from the drain pipe 230 is a mixture of scale and water, its temperature is relatively high. By aligning the drain pipe 230 towards the first heat exchanger 400, the water output from the water softener 100 can absorb the heat carried by the wastewater, reducing heat loss and thus increasing the water temperature. This reduces the amount of steam required for subsequent heating, lowers energy consumption, and improves the thermal efficiency of the boiler 200.

[0031] Specifically, referring to Figure 1, the boiler 200 is also provided with a blowdown expansion container 240, the output end of the blowdown pipe 230 is connected to the blowdown expansion container 240, the blowdown expansion container 240 is used to contain sewage, and the first heat exchanger 400 is arranged inside the blowdown expansion container 240. One end of the drain pipe 230 is connected to the boiler 200, and the other end is connected to the drain expansion container 240, so that the sewage from the boiler 200 can be discharged into the drain expansion container 240 through the drain pipe 230. This allows the high-temperature sewage discharged from the boiler 200 to remain stably in the drain expansion container 240. By setting the first heat exchanger 400 in the drain expansion container 240, the heat exchange time between the water output from the water softener 100 and the sewage can be extended, and the heat of the sewage can be fully recovered and utilized. This reduces the steam consumption of the deaerator 300 and lowers the discharge temperature of the sewage, reducing environmental thermal pollution, which is beneficial for energy conservation and environmental protection. It also improves the thermal efficiency of the entire boiler thermal deaeration energy-saving system, achieving more efficient energy saving and emission reduction, and effectively reducing the operating cost of the boiler 200.

[0032] In addition, the sewage expansion container 240 can temporarily store sewage, avoiding environmental pollution, facilitating centralized sewage treatment, and improving ease of use.

[0033] As can be understood, referring to Figure 1, a second water pump 800 is installed between the hot water exchange tank 110 and the deaerator 300. The second water pump 800 is used to drive water from the hot water exchange tank 110 into the deaerator 300. By installing the second water pump 800 between the hot water exchange tank 110 and the deaerator 300, water can be actively driven from the hot water exchange tank 110 into the deaerator 300, effectively overcoming the resistance that water may encounter when flowing in the pipe, ensuring that water can enter the deaerator 300 stably and continuously, and precisely controlling the water flow rate into the deaerator 300, so that the deaerator 300 can perform deaeration operation under stable water flow conditions, thereby improving the deaeration effect.

[0034] As can be understood, referring to Figure 1, the steam output pipe 210 is equipped with multiple output units 211, which are spaced apart within the deaerator 300. By arranging these multiple output units 211 at intervals within the deaerator 300, the high-temperature steam generated by the boiler 200 can be evenly distributed within the deaerator 300. This ensures that the water within the deaerator 300 is in full contact with the steam at all locations, improving the heat exchange efficiency between steam and water. This ensures that the water is heated more quickly and evenly, thereby more effectively releasing dissolved oxygen and enhancing the deaeration effect. Simultaneously, the evenly distributed steam also avoids localized areas of insufficient steam leading to excessively low water temperatures, as well as localized areas of excessive steam causing heat waste. This makes the heat distribution within the deaerator 300 more rational, improving the deaeration effect while reducing steam consumption and lowering the operating costs of the boiler 200.

[0035] As can be understood, referring to Figure 1, the input and output ends of the hot water exchange tank 110 are respectively arranged at the upper and lower ends of the hot water exchange tank 110. By setting the input and output ends of the hot water exchange tank 110 at the upper and lower ends respectively, the water output from the water softener 100 can be input from the upper end of the hot water exchange tank 110 and output from the lower end of the hot water exchange tank 110. This allows the water to fully contact the second heat exchanger 500, improving the efficiency of heat exchange and enabling the water to efficiently absorb heat, thus achieving a better preheating effect.

[0036] As can be understood, referring to Figure 1, an economizer 221 is installed at the end of the flue pipe 220 near the boiler 200. The cross-sectional area of ​​the economizer 221 is larger than that of the flue pipe 220, and the third heat exchanger 600 is arranged inside the economizer 221. By setting the cross-sectional area of ​​the economizer 221 to be larger than that of the flue pipe 220 and arranging the third heat exchanger 600 inside the economizer 221, the flow velocity of the flue gas is reduced and the residence time is extended when passing through the economizer 221. This allows the third heat exchanger 600 to have more time to exchange heat with the flue gas, thereby more efficiently absorbing the waste heat in the flue gas, reducing flue heat loss, reducing the additional energy consumption required by the boiler 200 to heat water, and further reducing the operating cost of the boiler 200.

[0037] Specifically, referring to Figure 1, the economizer 221 is connected to a drain valve 222, which is located at the lower end of the economizer 221 and is used to discharge condensate. The drain valve 222 at the lower end of the economizer 221 allows the condensate formed during heat exchange between the flue gas and the third heat exchanger 600 to be discharged through the exhaust pipe 220, preventing condensate buildup in the exhaust pipe 220, reducing damage to the equipment from accumulated water, improving system stability and reliability, and ensuring smooth heat exchange between the flue gas and the third heat exchanger 600, maintaining the system's efficient heat recovery capability.

[0038] Specifically, referring to Figure 1, the inner bottom wall of the energy-saving device 221 is inclined to guide condensate water to flow towards the drain valve 222. By setting the inner bottom wall of the energy-saving device 221 to be inclined, the condensate water can be effectively guided to flow towards the drain valve 222. The inclined inner bottom wall utilizes gravity to allow the condensate water to naturally converge along the inclined direction to the location of the drain valve 222, avoiding condensate water from remaining inside the energy-saving device 221 and improving the efficiency of condensate water discharge.

[0039] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A boiler thermal deaeration and energy-saving system, characterized in that, include: Water softener, boiler, deaerator, first heat exchanger, second heat exchanger and third heat exchanger; The water softener is used to soften water. The output end of the water softener is connected to the first heat exchanger. The output end of the first heat exchanger is connected to a hot water tank. The output end of the hot water tank is connected to the input end of the deaerator. The boiler is equipped with a steam output pipe, a flue pipe, and a drain pipe. The boiler is used to generate steam, which is output to the deaerator through the steam output pipe. The flue pipe is used to discharge the flue gas from the boiler. The drain pipe is used to discharge the wastewater from the boiler, and the output end of the drain pipe faces the first heat exchanger. The output end of the deaerator, the second heat exchanger, the third heat exchanger, and the boiler are connected in sequence. The second heat exchanger is arranged in the hot water tank, and the third heat exchanger is arranged in the flue pipe. A first water pump is provided between the second heat exchanger and the third heat exchanger. The first water pump is used to drive water from the second heat exchanger to the third heat exchanger.

2. The boiler thermal deaeration and energy-saving system according to claim 1, characterized in that, The boiler is also equipped with a blowdown expansion container, the output end of the blowdown pipe is connected to the blowdown expansion container, the blowdown expansion container is used to contain the wastewater, and the first heat exchanger is arranged inside the blowdown expansion container.

3. The boiler thermal deaeration and energy-saving system according to claim 1, characterized in that, A second water pump is provided between the hot water exchange tank and the deaerator. The second water pump is used to drive water from the hot water exchange tank into the deaerator.

4. The boiler thermal deaeration and energy-saving system according to claim 1, characterized in that, The steam output pipe is provided with multiple output units, which are arranged at intervals within the deaerator.

5. The boiler thermal deaeration and energy-saving system according to claim 1, characterized in that, The input and output ends of the hot water exchange tank are respectively located at the upper and lower ends of the hot water exchange tank.

6. The boiler thermal deaeration and energy-saving system according to claim 1, characterized in that, An economizer is installed at the end of the flue pipe near the boiler. The cross-sectional area of ​​the economizer is larger than that of the flue pipe. The third heat exchanger is arranged inside the economizer.

7. The boiler thermal deaeration and energy-saving system according to claim 6, characterized in that, The energy-saving device is connected to a drain valve, which is located at the lower end of the energy-saving device and is used to drain condensate.

8. The boiler thermal deaeration and energy-saving system according to claim 7, characterized in that, The inner bottom wall of the energy-saving device is inclined to guide the condensate to flow towards the drain valve.

Images