A heat type deaerator flash heat energy recovery device

Abstract

The utility model discloses a kind of for thermal type deaerator flash evaporation heat energy recovery device, it is related to heat energy recovery technical field, its technical scheme main point is: heat exchanger, it is equipped with mutually isolated flash evaporation channel and circulating water channel;Flash evaporation recovery pipeline is used to introduce the flash evaporation steam of deaerator discharge port into the flash evaporation channel entrance of heat exchanger;Flash evaporation pipeline electric switch valve, it is equipped on the flash evaporation recovery pipeline;Effect is the low-temperature flash evaporation steam of deaerator discharge, originally directly discarded, is introduced into heat exchanger, and high-efficiency heat exchange is carried out with circulating water, this act not only recovers the latent heat in large quantities in flash evaporation steam, for continuously heating circulating water, improve the grade and utilization value of heat energy, more clean condensed water produced after exchange is recovered, realizes the double recycling of heat energy and water resources, directly solves the energy waste problem pointed out in background technology from source, effectively reduce the operating cost of boiler system.

Description

Technical Field

[0001] This utility model relates to the field of heat energy recovery technology, and more specifically, it relates to a flash heat energy recovery device for a thermal deaerator. Background Technology

[0002] Thermal deaerators are key equipment in boiler water treatment systems. They remove dissolved oxygen from soft water by introducing high-temperature steam into the deaerator head. The deaerated water is stored in the deaerator tank, while the released oxygen, some residual steam, and non-condensable gases such as pressurized condensate are discharged from the exhaust port at the top of the deaerator.

[0003] When the pressurized condensate is discharged into the atmosphere, it undergoes secondary evaporation due to a sudden drop in pressure, forming flash steam. Currently, this flash steam is usually directly discharged into the atmosphere, resulting in a large amount of low-temperature heat energy contained within it not being recovered and utilized, causing energy waste and increasing the operating costs of the boiler system. At the same time, the direct discharge of flash steam also causes environmental thermal pollution and forms visible white vapor around the boiler room, affecting the production environment and corporate image. Existing technologies lack a dedicated device that can effectively and safely recover this flash steam heat energy, especially in terms of ensuring the normal back pressure of the deaerator, preventing system overpressure, and achieving efficient heat energy conversion.

[0004] Therefore, in order to solve the above-mentioned technical problems, this application proposes a flash heat recovery device for thermal deaerators. Utility Model Content

[0005] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a flash heat energy recovery device for thermal deaerators.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a flash heat recovery device for a thermal deaerator, comprising: The heat exchanger is equipped with mutually isolated flash evaporation channels and circulating water channels; Deaerator; An oxygen content detector is installed outside the deaerator to monitor the dissolved oxygen content in the water after deaeration online. Flash recovery pipeline is used to introduce flash steam from the deaerator discharge port into the flash channel inlet of the heat exchanger; An electrically operated switch valve for the flash evaporation pipeline is installed on the flash evaporation recovery pipeline; A heat exchange vent is located at the top of the flash evaporation channel of the heat exchanger; The condensate recovery pipeline has its inlet connected to the outlet of the flash evaporation channel of the heat exchanger; A hot water tank is used to store the water required for heat exchange and flash condensate. A hot water circulation pipeline connects the hot water tank and the circulating water channel of the heat exchanger, forming a closed loop; A hot water circulation pump is installed on the hot water circulation pipeline; A pressure sensor is installed on the flash channel of the heat exchanger to detect its internal pressure; The pressure sensor is connected to the electric switching valve of the flash pipeline.

[0007] Preferably, the heat exchanger vent is equipped with an automatic exhaust valve.

[0008] Preferably, the outlet of the condensate recovery pipe is connected to the hot water tank, and the pipe is covered with an insulation layer.

[0009] Preferably, the hot water circulation pipeline is covered with an insulation layer.

[0010] Preferably, the hot water circulation pump is a variable frequency pump.

[0011] Preferably, the hot water circulation pump is configured with one pump in use and one on standby.

[0012] Preferably, the outer wall of the hot water tank is provided with an insulation layer.

[0013] Preferably, it also includes a flow meter, which is installed on at least one of the hot water circulation pipeline and the condensate recovery pipeline.

[0014] Preferably, the system also includes a controller, wherein the pressure sensor, the electric switching valve of the flash pipeline, and the hot water circulation pump are all electrically connected to the controller.

[0015] Preferably, the controller is configured to close the electric switching valve of the flash pipeline when the pressure value detected by the pressure sensor is ≥0.02MPa.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. In this utility model, by setting up a recovery system consisting of a heat exchanger, a flash recovery pipeline, and a condensate recovery pipeline, the low-temperature flash steam discharged from the deaerator, which was originally directly discarded, is creatively introduced into the heat exchanger to conduct efficient heat exchange with the circulating water. This not only recovers a large amount of latent heat in the flash steam for continuous heating of the circulating water, improving the quality and utilization value of the heat energy, but also recovers the clean condensate generated after the exchange, realizing the dual recovery and utilization of heat energy and water resources. This directly solves the energy waste problem pointed out in the background art from the source and effectively reduces the operating cost of the boiler system.

[0017] 2. In this utility model, by introducing a pressure sensor and linking it with the electric switching valve signal of the flash pipeline, this design can monitor the pressure status of the flash side of the heat exchanger in real time. When the system malfunctions or the back pressure rises abnormally to the preset safety threshold (0.02MPa), it can immediately and automatically cut off the flash supply and switch to the direct atmospheric discharge mode. This active safety measure fundamentally eliminates the risk of impact or even damage to the deaerator body due to system overpressure, reliably ensuring the stable and safe operation of the core equipment of the boiler feedwater system—the deaerator, and solving the defect of lacking safety redundancy protection in the traditional method. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structural layout of this utility model; Figure 2 This is a flowchart illustrating the process of this utility model.

[0019] 1. Heat exchanger; 2. Heat exchange vent; 3. Flash recovery pipeline; 4. Electric on / off valve for flash pipeline; 5. Condensate recovery pipeline; 6. Hot water circulation pipeline; 7. Hot water circulation pump; 8. Hot water tank; 9. Flow meter; 10. Pressure sensor; 11. Deaerator; 12. Oxygen content detector. Detailed Implementation

[0020] like Figures 1-2 As shown, this utility model provides a flash heat recovery device for a thermal deaerator, comprising: The heat exchanger 1 is provided with mutually isolated flash evaporation channels and circulating water channels. It should be noted that the heat exchanger 11 is a plate or shell-and-tube heat exchanger 1, which is provided with mutually isolated flash evaporation channels and circulating water channels inside, so as to realize non-contact heat exchange between the two media.

[0021] The deaerator 11 and the oxygen content detector 12 are located outside the deaerator 11 and are used to monitor the dissolved oxygen content in the water after deaeration online. It should be noted that, in the embodiment, the deaerator 11 is connected to the oxygen content detector 12. The oxygen content detector 12 is an online dissolved oxygen monitoring device, and its main function is to verify whether the deaerator 11 has a deoxygenation effect during the use of this deoxygenation flash evaporation recovery system. In this embodiment, to ensure that the flash heat recovery process does not affect the core deoxygenation function of the thermal deaerator 11 and to ensure that the boiler feedwater quality meets the national mandatory standards, this device is equipped with a verification and monitoring system. According to the provisions of GB / T 1576-2018 Industrial Boiler Water Quality, steam boilers with a rated evaporation capacity of ≥7.0MW are required to undergo forced deoxygenation, and the dissolved oxygen content of the feedwater should be ≤0.05mg / L. For this purpose, an oxygen content detector 12 is installed at the outlet of the deaerator 11 or at the deaerated water tank. This detector is a dissolved oxygen analyzer used to monitor the deaerated water in real time online. It should be noted that the main function of the oxygen content detector 12 is to verify whether the flash heat recovery system has a negative impact on the deoxygenation effect of the deaerator 11 during operation. Its monitoring data is a key basis for evaluating the safety and reliability of the system. By comparing the dissolved oxygen data of the feed water before and after the flash recovery system is turned on, it can be clearly proven that this utility model does not change the internal working conditions and pressure balance of the deaerator while efficiently recovering heat energy, thus ensuring that its deoxygenation efficiency is stable and meets the standards.

[0022] Flash recovery pipeline 3 is used to introduce the flash steam from the exhaust port of deaerator 11 into the flash channel inlet of heat exchanger 1. The electric switch valve 4 of the flash evaporation pipeline is installed on the flash recovery pipeline 3; It should be noted that the inlet of the flash recovery pipeline 3 is connected to the original discharge port at the top of the deaerator 11 via a flange, and its outlet is connected to the flash channel inlet of the heat exchanger 1. An electric on / off valve 4 is connected in series on the flash recovery pipeline 3 to control the on / off state of the pipeline.

[0023] Heat exchange vent 2 is located at the top of the flash evaporation channel of heat exchanger 1, and the vent of heat exchanger 1 is equipped with an automatic exhaust valve. It should be noted that the exhaust port 2 of heat exchanger 1 is located at the highest point of the flash evaporation channel of heat exchanger 11, and preferably an automatic exhaust valve (not shown separately in the figure) is installed on it to automatically discharge the non-condensable gases accumulated during the heat exchange process, so as to ensure heat exchange efficiency.

[0024] The condensate recovery pipe 5 has its inlet connected to the flash evaporation channel outlet of the heat exchanger 1, and its outlet connected to the hot water tank 8. The pipe is also covered with an insulation layer. Hot water tank 8 is used to store the water required for heat exchange and flash condensate. The outer wall of hot water tank 8 is equipped with a heat insulation layer. In other words, hot water tank 8 is used to store the heat exchange water initially injected into the system and the recovered flash condensate. Its outer wall is equipped with a heat insulation layer to reduce heat loss. Hot water circulation pipe 6 is connected between hot water tank 8 and circulating water channel of heat exchanger 1 to form a closed loop. Hot water circulation pipe 6 is covered with a heat insulation layer. Hot water circulation pipe 6 is connected between the lower outlet of hot water tank 8 and the inlet of circulating water channel of heat exchanger 1, and returns to the upper part of hot water tank 8 through the outlet of circulating water channel, thus forming a closed loop. It should be noted that the inlet of the condensate recovery pipe 5 is connected to the bottom outlet of the flash evaporation channel of the heat exchanger 1, and its outlet relies on gravity to flow and connects to the upper part of the hot water tank 8. In order to reduce heat loss, the outer wall of the condensate recovery pipe 5 is covered with an insulation layer (such as rock wool or polyurethane foam).

[0025] Hot water circulation pump 7 is installed on hot water circulation pipeline 6. Hot water circulation pump 7 is a variable frequency pump. Hot water circulation pump 7 adopts a one-in-one-standby configuration. It should be noted that the hot water circulation pump 7 is connected in series with the hot water circulation pipe 6 to provide power for the flow of circulating water in the loop. In this embodiment, a variable frequency pump is preferably used and can be configured as a redundant mode with one pump in use and one in standby. The water flow rate is controlled by adjusting the pump's operating frequency, thereby stabilizing the inlet and outlet temperature difference of the circulating water channel of the heat exchanger 1 and optimizing the heat exchange efficiency.

[0026] Pressure sensor 10 is installed on the flash evaporation channel of heat exchanger 1 to detect its internal pressure. Pressure sensor 10 is connected to the electric switching valve 4 of the flash evaporation pipeline.

[0027] It also includes a flow meter 9, which is installed on at least one of the hot water circulation pipe 6 and the condensate recovery pipe 5; Furthermore, flow meters 9 can be installed on the hot water circulation pipeline 6 and / or the condensate recovery pipeline 5 to measure the circulation water flow and condensate recovery volume, providing data support for energy efficiency management.

[0028] It also includes a controller, and the pressure sensor 10, the electric switch valve 4 of the flash pipeline and the hot water circulation pump 7 are all electrically connected to the controller. The controller is configured to control the electric switch valve 4 of the flash pipeline to close when the pressure value detected by the pressure sensor 10 is ≥0.02MPa. It should be noted that, as a preferred automated control scheme, a controller (not shown in the figure, such as a PLC) can also be set up. The pressure sensor 10, the electric switching valve 4 of the flash pipeline and the hot water circulation pump 7 are all electrically connected to the controller. The controller collects pressure signals in real time and can automatically execute the above-mentioned alarm, valve switching and water pump frequency conversion adjustment operations according to preset logic to realize the fully automatic intelligent operation of the system.

[0029] When the system starts, the hot water circulation pump 7 starts first, pumping the low-temperature water in the hot water tank 8 into the circulating water channel of the heat exchanger 1 through the hot water circulation pipe 6 for circulation. Simultaneously, the flash steam generated by the deaerator 11 is introduced into the flash channel of the heat exchanger 1 through the opened electric switch valve 4 of the flash pipe and the flash recovery pipe 3. Inside the heat exchanger 1, the high-temperature flash steam and the low-temperature circulating water exchange heat through the partition wall. The latent heat of the flash steam is absorbed by the circulating water, which condenses into condensate. The condensate flows back to the hot water tank 8 by gravity through the condensate recovery pipe 5, realizing the recovery of heat energy and water resources. The heated circulating water returns to the hot water tank 8, continuously raising the water temperature in the tank for use in production and daily life. Non-condensable gases such as air accumulated inside the heat exchanger 1 are discharged through the automatic vent valve at the heat exchanger 1's vent.

[0030] To ensure system safety, the pressure sensor 10 is connected to the electric switch valve 4 of the flash pipeline. When the pressure sensor 10 detects an abnormal increase in pressure in the flash channel of the heat exchanger 1 and reaches a preset safety value (e.g., 0.02 MPa), the system will immediately issue an alarm signal and control the electric switch valve 4 of the flash pipeline to close, cutting off the flash steam source. At this time, the flash steam of the deaerator 11 will be directly discharged to the atmosphere from its original vent pipeline, thereby effectively preventing the heat exchanger 1 from being damaged due to overpressure and ensuring the safety and stability of the deaerator 11's operation.

[0031] In summary, this utility model, by setting up a recovery system consisting of a heat exchanger 1, a flash recovery pipeline 3, and a condensate recovery pipeline 5, creatively introduces the low-temperature flash steam discharged from the deaerator 11, which was originally directly discarded, into the heat exchanger 1 for efficient heat exchange with the circulating water. This not only recovers a large amount of latent heat in the flash steam for continuous heating of the circulating water, improving the quality and utilization value of the heat energy, but also recovers the clean condensate generated after the exchange, achieving dual recovery and utilization of heat energy and water resources. This directly solves the energy waste problem pointed out in the background art from the source and effectively reduces the operating cost of the boiler system.

[0032] Meanwhile, one of the core features of this invention is the introduction of a pressure sensor 10 that is linked to the electric switching valve 4 of the flash pipeline. This design can monitor the pressure status of the flash side of the heat exchanger 1 in real time. When the system fails or the back pressure rises abnormally to the preset safety threshold (0.02MPa), it can immediately and automatically cut off the flash supply and switch to the direct atmospheric discharge mode. This active safety measure fundamentally eliminates the risk of impact or even damage to the deaerator 11 body due to system overpressure, and reliably ensures the stable and safe operation of the core equipment of the boiler feedwater system—the deaerator 11, solving the defect of lacking safety redundancy protection in the traditional method.

[0033] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any way. Those skilled in the art can readily implement this utility model based on the accompanying drawings and the above description. However, any modifications, alterations, or equivalent variations made by those skilled in the art without departing from the scope of the utility model's technical solution, utilizing the disclosed technical content, are considered equivalent embodiments of this utility model. Furthermore, any equivalent changes, alterations, or variations made to the above embodiments based on the essential technology of this utility model are still within the protection scope of this utility model's technical solution.

Claims

1. A flash heat recovery device for a thermal deaerator, characterized in that, include: The heat exchanger (1) is provided with a flash evaporation channel and a circulating water channel that are isolated from each other; Deaerator (11); An oxygen content detector (12) is installed outside the deaerator (11) and is used to monitor the dissolved oxygen content in the water after deoxygenation online. Flash recovery pipeline (3) is used to introduce flash steam from the deaerator (11) outlet into the flash channel inlet of the heat exchanger (1); An electric switch valve (4) for the flash evaporation pipeline is installed on the flash recovery pipeline (3); A heat exchange vent (2) is located at the top of the flash evaporation channel of the heat exchanger (1); The condensate recovery pipeline (5) has its inlet connected to the flash evaporation channel outlet of the heat exchanger (1); Hot water tank (8) is used to store water required for heat exchange and flash condensate; Hot water circulation pipe (6) is connected between the hot water tank (8) and the circulating water channel of the heat exchanger (1) to form a closed loop; A hot water circulation pump (7) is installed on the hot water circulation pipeline (6); A pressure sensor (10) is installed on the flash channel of the heat exchanger (1) to detect its internal pressure; The pressure sensor (10) is connected to the electric switching valve (4) of the flash pipeline.

2. The flash heat recovery device for a thermal deaerator according to claim 1, characterized in that: The heat exchanger (1) is equipped with an automatic exhaust valve at its vent.

3. The flash heat recovery device for a thermal deaerator according to claim 1, characterized in that: The outlet of the condensate recovery pipeline (5) is connected to the hot water tank (8), and the pipeline is covered with an insulation layer.

4. The flash heat recovery device for a thermal deaerator according to claim 1, characterized in that: The hot water circulation pipe (6) is covered with an insulation layer.

5. A flash heat recovery device for a thermal deaerator according to claim 1, characterized in that: The hot water circulation pump (7) is a variable frequency pump.

6. A flash heat recovery device for a thermal deaerator according to claim 5, characterized in that: The hot water circulation pump (7) is configured with one pump in use and one pump on standby.

7. A flash heat recovery device for a thermal deaerator according to claim 1, characterized in that: The hot water tank (8) has an insulation layer on its outer wall.

8. A flash heat recovery device for a thermal deaerator according to claim 1, characterized in that: It also includes a flow meter (9), which is installed on at least one of the hot water circulation pipeline (6) and the condensate recovery pipeline (5).

9. A flash heat recovery device for a thermal deaerator according to claim 1, characterized in that: It also includes a controller, and the pressure sensor (10), the electric switching valve (4) of the flash pipeline and the hot water circulation pump (7) are all electrically connected to the controller.

10. A flash heat recovery device for a thermal deaerator according to claim 9, characterized in that: The controller is configured to close the electric switching valve (4) of the flash pipeline when the pressure value detected by the pressure sensor (10) is ≥0.02MPa.

Images