Fixed-discharge steam recovery device of heating power gas-fired boiler

Abstract

The utility model relates to the technical field of thermal boiler production, and discloses a thermal gas-fired boiler regular-discharge steam recovery device which comprises a boiler regular-discharge flash tank. The air outlet pipe is communicated with the top of the boiler periodic blowdown flash tank, a heat exchanger is installed at the top end of the air outlet pipe, an exhaust pipe is arranged above the heat exchanger, and an extension pipe is communicated between the heat exchanger and the exhaust pipe; according to the utility model, the heat exchanger is additionally arranged at the exhaust port of the existing boiler periodic blowdown flash tank and is matched with the recycling mechanism for use, so that the waste heat of boiler blowdown dead steam is effectively recycled, the energy utilization efficiency is improved, the operation cost is reduced, and the dead steam is condensed in the heat exchanger to form high-quality condensed water; and the preheated demineralized water enters the deaerator, so that the steam demand is reduced, the deaerator operates more stably, the phenomenon of white smoke plume caused by direct discharge of dead steam can be eliminated, and the factory environment is improved.

Description

Technical Field

[0001] This utility model relates to the field of thermal boiler production technology, specifically a steam recovery device for a thermal gas boiler. Background Technology

[0002] In the operation of thermal gas-fired boilers, regular blowdown is a key process to ensure the safe and efficient operation of the boiler. During blowdown, the high-temperature, high-pressure water discharged from the bottom of the boiler (usually containing a large amount of dissolved impurities) enters the blowdown expansion tank. Due to the sudden pressure drop, some of the hot water is rapidly flash-evaporated into secondary steam. This secondary steam not only carries a large amount of high-quality heat energy, but its condensate is also a valuable water resource.

[0003] Directly discharging this type of steam will lead to two prominent problems: first, it will cause significant heat loss and water waste, affecting the company's energy efficiency indicators; second, the white plume formed by the steam emission will cause visual pollution to the factory area. Therefore, achieving efficient recovery and utilization of steam emitted from boiler blowdown expansion tanks has become an important technical issue in the field of industrial energy conservation and emission reduction. Utility Model Content

[0004] The purpose of this invention is to provide a steam recovery device for a thermal gas boiler with constant discharge steam, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a steam recovery device for a thermal gas-fired boiler, comprising a boiler steam expansion tank, and further comprising:

[0006] A drain pipe is connected to the inner wall of the boiler's fixed-discharge expansion container, and a drain pipe is connected to the bottom of the boiler's fixed-discharge expansion container;

[0007] An exhaust pipe is connected to the top of the boiler's fixed-discharge expansion vessel. A heat exchanger is installed at the top of the exhaust pipe, and an exhaust pipe is provided above the heat exchanger. An extension pipe connects the heat exchanger and the exhaust pipe.

[0008] A connector is provided between the outlet pipe, the heat exchanger, and the extension pipe for assembly.

[0009] A recovery mechanism installed inside the heat exchanger for utilizing boiler blowdown steam.

[0010] Preferably, the bottom of the boiler's fixed-discharge expansion vessel is fixed with three support legs, which are arranged in a circular array.

[0011] Preferably, the connector includes a flange fixed to the outside of the outlet pipe, heat exchanger and extension pipe, and the outside of the flange is provided with a sealing groove for placing a sealing ring.

[0012] Preferably, the recycling mechanism includes a heat exchange tube fixed to the inner wall of the heat exchanger, the heat exchange tube being a round tube made of copper, and the outer tube of the heat exchanger being made of stainless steel.

[0013] Preferably, the inner wall of the heat exchanger is connected to a demineralized water inlet pipe and a demineralized water outlet pipe, respectively. The inlet of the demineralized water inlet pipe is located at the top of the heat exchanger, and the outlet of the demineralized water outlet pipe is located at the bottom of the heat exchanger.

[0014] Preferably, the heat exchanger has an internal cavity, and a spiral plate is installed inside the cavity, with the spiral plate fixed between the heat exchange tube and the heat exchanger.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] This invention achieves effective recovery and utilization of waste heat from boiler blowdown steam by adding a heat exchanger to the exhaust port of the existing boiler blowdown expansion vessel and using a recovery mechanism. This improves energy efficiency, reduces operating costs, and the waste steam condenses in the heat exchanger to form high-quality condensate, which can be recycled to the cooling pool for reuse, improving water resource utilization. The preheated demineralized water enters the deaerator, reducing steam demand and making the deaerator operation more stable. It also eliminates the "white plume" phenomenon caused by direct exhaust steam emission, improves the plant environment, and avoids visual pollution. Attached Figure Description

[0017] Figure 1 A schematic diagram of a preferred embodiment of the thermal gas boiler constant discharge steam recovery device provided by this utility model;

[0018] Figure 2 A schematic diagram of the structure of the outlet pipe, heat exchanger and extension pipe provided by this utility model after connection;

[0019] Figure 3 A schematic diagram of the disassembled structure of the outlet pipe, heat exchanger and extension pipe provided by this utility model;

[0020] Figure 4 A schematic diagram of the structure of the connector provided by this utility model;

[0021] Figure 5 A schematic diagram of the recycling mechanism provided by this utility model.

[0022] In the diagram: 1. Boiler blowdown expansion vessel; 2. Sewage pipe; 3. Drainage pipe; 4. Gas outlet pipe; 5. Heat exchanger; 6. Exhaust pipe; 7. Extension pipe; 8. Connecting parts; 81. Flange; 82. Sealing groove; 9. Recovery mechanism; 91. Heat exchange tube; 92. Demineralized water inlet pipe; 93. Demineralized water outlet pipe; 94. Cavity; 95. Spiral plate; 10. Support leg. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] Please see Figure 1-5 As shown, a steam recovery device for a gas-fired boiler includes a boiler steam expansion container 1 and a drain pipe 2 connected to the inner wall of the boiler steam expansion container 1. A drain pipe 3 is connected to the bottom of the boiler steam expansion container 1. The boiler steam expansion container 1 is a key device for depressurizing and expanding the boiler's periodic wastewater or high-pressure waste hot water. Its working principle is to reduce the wastewater pressure through a throttle valve, causing the high-pressure saturated water to expand adiabatably in the expansion container and separate into secondary steam and waste hot water. The drain pipe 2 is used to transport the boiler's periodic wastewater or high-pressure waste hot water into the boiler steam expansion container 1, and the drain pipe 3 is used to discharge the recovered condensate and waste hot water.

[0025] The outlet pipe 4 is connected to the top of the boiler blowdown expansion vessel 1. A heat exchanger 5 is installed at the top of the outlet pipe 4. An exhaust pipe 6 is installed above the heat exchanger 5. An extension pipe 7 connects the heat exchanger 5 and the exhaust pipe 6. The outlet pipe 4 facilitates the discharge of high-temperature steam separated from the boiler blowdown expansion vessel 1. The heat exchanger 5 is connected to the outlet pipe 4, allowing high-temperature steam to pass through the heat exchanger 5. The heat exchanger 5 has a pipe diameter of 600 mm. The outer tube of the heat exchanger 5 is made of stainless steel, which utilizes its excellent corrosion resistance and high strength to ensure long-term stable operation of the equipment under harsh conditions. The exhaust pipe 6 facilitates the discharge of cooled steam to another device. The extension pipe 7 added to the upper part of the heat exchanger 5 allows the boiler blowdown steam to flow in the shell side of the heat exchanger 5, while the demineralized water flows in the tube side, forming an efficient heat exchange path.

[0026] A connector 8 is installed between the outlet pipe 4, heat exchanger 5, and extension pipe 7 for assembly. The connector 8 connects the outlet pipe 4, heat exchanger 5, and extension pipe 7. The connector 8 includes a flange 81 fixed to the outside of the outlet pipe 4, heat exchanger 5, and extension pipe 7. A sealing groove 82 for placing a sealing ring is opened on the outside of the flange 81. The outlet pipe 4, heat exchanger 5, and extension pipe 7 can be assembled by using the flange 81. During assembly, a rubber sealing ring is placed in the sealing groove 82. Finally, the outlet pipe 4, heat exchanger 5, and extension pipe 7 are connected and fixed by the use of bolts, gaskets, and nuts, which can effectively prevent gas leakage.

[0027] A recovery mechanism 9, installed inside the heat exchanger 5, is used to utilize boiler blowdown steam. This mechanism allows for the recovery and reuse of high-temperature steam, preventing resource waste. The recovery mechanism 9 includes heat exchange tubes 91 fixed to the inner wall of the heat exchanger 5. The heat exchange tubes 91 are round tubes made of copper, while the outer tube of the heat exchanger 5 is made of stainless steel. The copper tubes 91, due to their excellent thermal conductivity, significantly improve heat exchange efficiency. Based on actual heat exchange requirements and installation space limitations, the specifications of the heat exchange tubes 91 are determined to be an outer diameter of 20 mm and a wall thickness of 2 mm. The heat exchanger 5 has a diameter of 1 meter and a length of 1 meter. The inner wall of the heat exchanger 5 is connected to a demineralized water inlet pipe 92 and a demineralized water outlet pipe 93. The inlet of the demineralized water inlet pipe 92 is located at the top of the heat exchanger 5, and the outlet of the demineralized water outlet pipe 93 is located at the bottom of the heat exchanger 5. A cavity 94 is provided inside the heat exchanger 5, and a spiral plate 95 is installed inside the cavity 94. The spiral plate 95 is fixed between the heat exchange tube 91 and the heat exchanger 5. The spiral plate 95 can be installed by creating a cavity 94 inside the heat exchanger 5, thus fixing the spiral plate 95 between the heat exchange tube 91 and the heat exchanger 5. When the height... Warm boiler blowdown steam enters heat exchanger 5 and comes into contact with the tube wall of heat exchange tube 91. Because the steam temperature is significantly higher than the tube wall temperature, according to the principle of heat transfer, the steam rapidly transfers heat to the tube wall. The tube wall itself cools and begins to condense into water. The heated tube wall then transfers this heat to the demineralized water flowing on the spiral plate 95 outside the heat exchange tube 91. The demineralized water flowing on the spiral plate 95 enters through the demineralized water inlet pipe 92, causing the temperature of the demineralized water to gradually increase. Through this process, the waste heat from the boiler blowdown steam is recovered and utilized, successfully constructing a system... The closed-loop heat recovery system effectively reduces energy waste and improves the overall energy efficiency of the system. The low-temperature demineralized water (initial temperature 35℃) exchanges heat with the exhaust steam in the heat exchanger 5 in a countercurrent manner, absorbing the latent heat of vaporization and raising the temperature to 55-60℃, while allowing the exhaust steam to condense fully. The preheated demineralized water is transported to the deaerator through the demineralized water outlet pipe 93, which not only increases the inlet water temperature and reduces the consumption of deaeration steam, but also improves the deaeration efficiency. During the heat exchange process of the low-temperature demineralized water, a large amount of heat is absorbed, causing the steam after doing work to condense into water. The condensate is collected in the cooling pool and reused, realizing the recycling of water resources.

[0028] The bottom of the boiler fixed exhaust expansion vessel 1 is fixed with three support legs 10. The three support legs 10 are arranged in a circular array. By setting the three support legs 10, the boiler fixed exhaust expansion vessel 1 can be supported and fixed, thereby improving the working stability of the boiler fixed exhaust expansion vessel 1.

[0029] Working principle: The boiler periodically discharges wastewater or high-pressure wastewater to the boiler blowdown expansion vessel 1. The boiler blowdown expansion vessel 1 processes the wastewater to generate high-temperature exhaust steam. The high-temperature exhaust steam enters the heat exchanger 5 through the outlet pipe 4 and comes into contact with the tube wall of the heat exchange tube 91. The high-temperature steam transfers heat to the tube wall, and the tube wall of the heat exchange tube 91 begins to condense into water upon contact with the cold air. The tube wall, having gained heat, then transfers the heat to the demineralized water flowing on the spiral plate 95 on the outside of the heat exchange tube 91, causing the temperature of the demineralized water to gradually rise. The preheated demineralized water is then transported to the deaerator through the demineralized water outlet pipe 93. During the heat exchange process, the low-temperature demineralized water absorbs a large amount of heat, causing the steam after doing work to condense into water. The condensate is collected in the cooling pool and reused, realizing the recycling of water resources.

[0030] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0031] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A thermal gas boiler exhaust steam recovery device comprising a boiler exhaust expander (1), characterized in that it also comprises include: A drain pipe (2) is connected to the inner wall of the boiler fixed discharge expansion container (1), and a drain pipe (3) is connected to the bottom of the boiler fixed discharge expansion container (1). An exhaust pipe (4) is connected to the top of the boiler fixed exhaust expansion vessel (1). A heat exchanger (5) is installed at the top of the exhaust pipe (4). An exhaust pipe (6) is provided above the heat exchanger (5). An extension pipe (7) is connected between the heat exchanger (5) and the exhaust pipe (6). A connector (8) is provided between the outlet pipe (4), the heat exchanger (5) and the extension pipe (7) for assembly. A recovery mechanism (9) is installed inside the heat exchanger (5) for utilizing boiler blowdown steam.

2. A thermal gas boiler emission control steam recovery device according to claim 1, characterized in that: The bottom of the boiler fixed exhaust expansion vessel (1) is fixed with three support legs (10), and the three support legs (10) are arranged in a ring array.

3. A thermal gas boiler emission control steam recovery device according to claim 1, characterized in that: The connector (8) includes a flange (81) fixed to the outside of the outlet pipe (4), heat exchanger (5) and extension pipe (7), and a sealing groove (82) for placing a sealing ring is provided on the outside of the flange (81).

4. A thermal gas boiler emission control steam recovery device according to claim 1, characterized in that: The recycling mechanism (9) includes a heat exchange tube (91) fixed to the inner wall of the heat exchanger (5), the heat exchange tube (91) being a round tube made of copper, and the outer tube material of the heat exchanger (5) being stainless steel.

5. A thermal gas boiler emission control steam recovery device according to claim 1, characterized in that: The inner wall of the heat exchanger (5) is connected to a demineralized water inlet pipe (92) and a demineralized water outlet pipe (93). The inlet of the demineralized water inlet pipe (92) is located at the top of the heat exchanger (5), and the outlet of the demineralized water outlet pipe (93) is located at the bottom of the heat exchanger (5).

6. A thermal gas boiler emission control and vapour recovery device according to claim 1, characterised in that: The heat exchanger (5) has a cavity (94) inside, and a spiral plate (95) is provided inside the cavity (94). The spiral plate (95) is fixed between the heat exchange tube (91) and the heat exchanger (5).

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