Composite single-tower system for heating and humidifying combustion-supporting air of gas-fired boiler

Abstract

The invention discloses a composite single-tower system for heating and humidifying combustion-supporting air of a gas-fired boiler, comprising: a tower body, the tower body comprising a flue gas heat release cavity and an air heat absorption cavity which are arranged up and down; the flue gas heat exchange tower comprises a flue gas heat release cavity, a flue gas heat exchange part and a flue gas heat exchange part, the flue gas heat exchange part is arranged in the flue gas heat release cavity, a flue gas inlet and outlet channel is arranged in the flue gas heat release cavity, a flue gas heat exchange spraying pipe is arranged above the flue gas heat exchange part, and the heat exchange tower can serve as a part of a chimney, so that the initial capital construction investment is effectively saved; according to the system, water circulation is achieved through equipment such as a circulating water pump, flue gas and air are subjected to heat exchange in different cavities in sequence, after water in a flue gas heat release cavity absorbs flue gas heat, part of water is fed into an air heat absorption cavity to continue to heat and humidify combustion-supporting air, the heat is fully utilized, the water dew point temperature of natural gas combustion flue gas is increased, and the combustion efficiency is improved. And therefore, the quality of natural gas smoke condensation latent heat is improved, and the utilization efficiency of natural gas smoke condensation latent heat energy is improved.

Description

Technical Field

[0001] The invention relates to the technical field of gas boiler improvement, in particular to a composite single-tower system for heating and humidifying combustion-supporting air of a gas boiler. Background Art

[0002] Nowadays, industrial steam boilers generally use natural gas, which is a valuable fuel and accounts for a large proportion of the cost in industrial production. Saving natural gas fuel has great economic value. As a combustible gas, natural gas has a high combustion efficiency and very little incomplete gas loss. In addition, the design of gas-fired steam boilers is very mature, and the energy-saving space of gas-fired steam boilers is very limited. If we want to further save natural gas in the gas-fired steam boiler system, we will face great challenges.

[0003] The vast majority of existing condensing steam boilers are cold-air integrated burners, and are not equipped with air preheaters, so they are unable to heat the combustion air; even if some condensing steam boilers are equipped with air preheaters, they are unable to humidify the air, resulting in a low flue gas water dew point temperature. When water is introduced at room temperature, the utilization of the flue gas condensation latent heat is very limited, and the possibility of improving the utilization of the boiler flue gas latent heat cannot be improved. Summary of the invention

[0004] The purpose of the present invention is to provide a composite single-tower system for heating and humidifying combustion air in a gas boiler. Without using various heat pumps and high-grade heat sources, the water dew point temperature of the flue gas is increased by humidifying the combustion air in a low-cost manner, thereby making deeper use of the latent heat of the flue gas to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a composite single-tower system for heating and humidifying combustion-supporting air in a gas boiler, comprising:

[0006] The tower body includes a smoke heat release chamber and an air heat absorption chamber arranged up and down;

[0007] A flue gas heat exchange unit, which is placed inside the flue gas heat release chamber, and a flue gas inlet and outlet channel is provided inside the flue gas heat release chamber. A flue gas heat exchange spray pipe is provided above the flue gas heat exchange unit, and a pipe connection part is installed in the middle of the flue gas heat exchange spray pipe, which is used to mix boiler feed water with circulating water at the bottom of the air heat absorption chamber and place the mixture in the flue gas heat exchange spray pipe;

[0008] The air heat exchange unit is placed inside the air heat absorption chamber, and the air heat absorption chamber is provided with an air inlet and outlet channel. An air heat exchange spray pipe is provided above the air heat exchange unit, and a pressurized water pump is installed at the end of the air heat exchange spray pipe to inject the water after heat exchange in the flue gas heat release chamber into the air heat exchange spray pipe for secondary heat exchange.

[0009] Preferably, the air heat exchange part and the flue gas heat exchange part are both composed of a plurality of corrugated plates stacked up and down.

[0010] Preferably, the smoke inlet and outlet channel includes a smoke inlet and a smoke exhaust pipe, the smoke inlet is fixedly connected to one side of the bottom of the smoke heat release chamber and is located below the smoke heat exchange part, the smoke exhaust pipe is fixedly connected to the top of the smoke heat release chamber, and a rain cover is installed on the top of the smoke exhaust pipe.

[0011] Preferably, the pipeline connection part includes a circulating water pipe and a water supply inlet pipe, the water supply inlet pipe and the circulating water pipe are both connected to the flue gas heat exchange spray pipe, the bottom of the circulating water pipe is connected to a circulating water pump, and the input end of the circulating water pump is inserted into the interior of the air heat absorption chamber.

[0012] Preferably, a water supply outlet pipe for drainage is fixedly connected to the bottom of the flue gas heat release chamber, and the input end of the pressure water pump is connected to the middle part of the water supply outlet pipe.

[0013] Preferably, a second demisting layer is installed inside the flue gas heat release chamber and above the flue gas heat exchange spray pipe, and a first demisting layer is installed inside the air heat absorption chamber and above the air heat exchange spray pipe.

[0014] Preferably, the demisting layer 1 and the demisting layer 2 are both made of metal mesh.

[0015] Preferably, the air inlet and outlet channel includes an air inlet and an air outlet, the air outlet is fixedly connected to one side of the air heat absorption chamber, the air inlet is located below the air heat exchange part, and the air outlet is fixedly connected to the outside of the smoke heat release chamber and located above the demisting layer one.

[0016] Preferably, a second equalizing plate is provided inside the flue gas heat release chamber and below the flue gas inlet, and a first equalizing plate is fixedly connected inside the air heat absorption chamber and below the air inlet.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: the tower body arranges the flue gas heat release chamber and the air heat absorption chamber in an upper and lower stack, which is extremely beneficial to the energy-saving project of industrial gas steam boilers, not only saving a large amount of boiler room space, but also the heat exchange tower itself can be used as a part of the chimney, effectively saving the initial infrastructure investment; the system realizes water circulation through equipment such as a circulating water pump, and the flue gas and air exchange heat in different chambers in turn. After the water in the flue gas heat release chamber absorbs the heat of the flue gas, part of it is sent to the air heat absorption chamber to continue to heat and humidify the combustion air, making full use of the heat, making full use of the heat, improving the water dew point temperature of the natural gas combustion flue gas, and then improving the quality of the latent heat of condensation of the natural gas flue gas, and increasing the energy utilization efficiency of the latent heat of condensation of the natural gas flue gas; the air used for combustion in the boiler room is sent into the air heat absorption chamber through the air inlet and outlet channel, and the combustion air contacts with the hot water sprayed from the air heat exchange part and the air heat exchange spray pipe from bottom to top, and is sent to the boiler combustion chamber after being heated and humidified. The heated combustion air can improve combustion, improve combustion efficiency, reduce CO emissions, and create conditions for controlling the low air excess coefficient of the burner. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention;

[0019] Figure 2 It is a schematic diagram of the internal structure of the tower body of the present invention;

[0020] Figure 3 This is a structural schematic diagram of the demisting layer 1 of the present invention;

[0021] Figure 4 It is a conveying route diagram of flue gas, water and air during heat exchange of the present invention.

[0022] In the figure: 1. tower body; 2. flue gas heat release chamber; 3. air heat absorption chamber; 4. air inlet; 5. air heat exchange unit; 6. air heat exchange spray pipe; 7. equalizing plate one; 8. circulating water pump; 9. air outlet; 10. demisting layer one; 11. pressurized water pump; 12. water supply outlet pipe; 13. equalizing plate two; 14. flue gas inlet; 15. flue gas heat exchange unit; 16. flue gas heat exchange spray pipe; 17. demisting layer two; 18. water supply inlet pipe; 19. circulating water pipe; 20. smoke exhaust pipe; 21. rain cover. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] See also Figure 1-Figure 4 The present invention provides a technical solution: a composite single-tower system for heating and humidifying combustion-supporting air in a gas boiler, comprising: a tower body 1, the tower body 1 comprising a flue gas heat release chamber 2 and an air heat absorption chamber 3 which are stacked up and down, and the stacking arrangement is very beneficial to the energy-saving project of industrial gas steam boilers, which not only saves a lot of boiler room space, but also the heat exchange tower itself can be used as a part of the chimney, and also saves the initial infrastructure investment, the flue gas heat release chamber 2 and the air heat absorption chamber 3 are divided into two independent chambers by a partition plate, and the two form independent heat exchange systems; the flue gas heat exchange part 15 is installed inside the flue gas heat release chamber 2, and the flue gas heat release chamber 2 is provided with a flue gas inlet and outlet channel, and a flue gas heat exchange part 15 is provided above the flue gas heat exchange part 15. The flue gas heat exchange spray pipe 16 is fixedly connected to the inner wall of the flue gas heat release chamber 2. A pipe connection part is installed in the middle of the flue gas heat exchange spray pipe 16, which is used to mix the boiler feed water with the circulating water at the bottom of the air heat absorption chamber 3 and place it in the flue gas heat exchange spray pipe 16; the air heat exchange part 5 is placed in the air heat absorption chamber 3, and the air inlet and outlet channels are arranged in the air heat absorption chamber 3. The inner wall of the air heat absorption chamber 3 and above the air heat exchange part 5 are fixedly connected with an air heat exchange spray pipe 6. A pressurized water pump 11 is installed at the end of the air heat exchange spray pipe 6. The output end of the pressurized water pump 11 is connected to the air heat exchange spray pipe 6, which is used to inject the water after heat exchange in the flue gas heat release chamber 2 into the air heat exchange spray pipe 6 for secondary heat exchange.

[0025] It should be noted that, in the present embodiment, the flue gas heat exchange spray pipe 16 is connected to the boiler feed water and the circulating water at the bottom of the air heat absorption chamber 3. In the air heat absorption chamber 3, the flue gas moves from bottom to top through the flue gas inlet and outlet channels. The flue gas passes through the middle of the flue gas heat exchange part 15 and contacts with the hot water sprayed from the flue gas heat exchange spray pipe 16. The flue gas is cooled and discharged from the top. The water sprayed by the flue gas heat exchange spray pipe 16 is cooled and falls on the bottom of the smoke heat release chamber 2 after heat exchange with the flue gas. The water after heat exchange and cooling at the bottom of the smoke heat release chamber 2 is discharged through the pressurized water pump 11 and then sent into the air heat exchange spray pipe 6. The air used for combustion in the boiler room is sent into the air heat absorption chamber 3 through the air inlet and outlet channels. In the air heat absorption chamber 3, the combustion air contacts the hot water sprayed from the air heat exchange unit 5 and the air heat exchange spray pipe 6 from bottom to top. The temperature of the combustion air is lower than the temperature of the water. The combustion air is heated and humidified by heat exchange and then discharged from one side of the air heat absorption chamber 3 and sent to the boiler combustion chamber. The heated combustion air can improve combustion, improve combustion efficiency, and reduce CO emissions, thereby creating conditions for controlling the low air excess coefficient of the burner. After the water sprayed from the air heat exchange spray pipe 6 is cooled by the air heat exchange unit 5 and the air, it enters the flue gas heat exchange spray pipe 16 again through the pipeline connection part. In this way, the composite single-tower system heats the combustion air and increases the flue gas water dew point temperature. It not only increases the utilization of the flue gas condensation latent heat when entering the water at room temperature, but also maximizes the possibility of utilizing the boiler flue gas latent heat under other working conditions. It is a deeper condensing boiler system.

[0026] In one embodiment, the air heat exchange part 5 and the smoke heat exchange part 15 are both composed of a plurality of corrugated plates stacked one above the other.

[0027] It should be noted that in this embodiment, the corrugated shape of the corrugated plate causes disturbances in the fluid during the flow process, increases the contact area between the gas or liquid and the heat exchange surface, and promotes heat transfer. The special structure of the corrugated plate will cause turbulent effects on the air or liquid flow, increase the disturbance of the fluid, effectively promote heat transfer, reduce the impact of the thermal boundary layer, and improve the heat exchange efficiency.

[0028] In one embodiment, the smoke inlet and outlet channel includes a smoke inlet 14 and a smoke exhaust pipe 20. The smoke inlet 14 is fixedly connected to one side of the bottom of the smoke heat release chamber 2 and is located below the smoke heat exchange part 15. The smoke exhaust pipe 20 is fixedly connected to the top of the smoke heat release chamber 2. A rain cover 21 is installed on the top of the smoke exhaust pipe 20.

[0029] It should be noted that in this embodiment, the hot flue gas is connected to the flue gas inlet 14, and the flue gas passes through the flue gas heat exchange part 15 from bottom to top through the flue gas inlet 14 and contacts the water sprayed from the flue gas heat exchange spray pipe 16, so that the temperature of the flue gas is reduced through heat exchange. The cooled flue gas enters the exhaust pipe 20 through the top of the smoke heat release chamber 2 and is then discharged. The rain cover 21 can prevent rainwater from entering the exhaust pipe 20.

[0030] In one embodiment, the pipeline connection part includes a circulating water pipe 19 and a water supply inlet pipe 18. The water supply inlet pipe 18 and the circulating water pipe 19 are both connected to the flue gas heat exchange spray pipe 16. The bottom of the circulating water pipe 19 is connected to a circulating water pump 8, and the input end of the circulating water pump 8 is inserted into the interior of the air heat absorption chamber 3.

[0031] It should be noted that, in this embodiment, the circulating water pump 8 sprays the water after heat exchange with the air from the air heat exchange spray pipe 6 through the circulating water pipe 19 and sends it into the flue gas heat exchange spray pipe 16, and the water enters the flue gas heat exchange spray pipe 16 through the water supply inlet pipe 18 and the boiler feed water through the water supply inlet pipe 18. The water entering the water supply inlet pipe 18 is cooled by the intersection of cold and hot, and then sprayed down to the flue gas heat exchange part 15 below through the flue gas heat exchange spray pipe 16, so as to exchange heat with the air entering the flue gas heat release chamber 2.

[0032] In one embodiment, a water supply outlet pipe 12 for drainage is fixedly connected to the bottom of the smoke heat release chamber 2 , and an input end of the pressure water pump 11 is connected to the middle of the water supply outlet pipe 12 .

[0033] It should be noted that, in this embodiment, the circulating water from the circulating pump and the boiler feed water are combined and flow downward from the flue gas heat exchange spray pipe 16 to exchange heat with the flue gas for temperature increase. After reaching the bottom of the flue gas heat release chamber 2, part of the hot water is diverted to the boiler through the water supply outlet pipe 12, and the remaining hot water enters the air heat absorption chamber 3 through the pressurized water pump 11 and the air heat exchange spray pipe 6, continues to release heat and humidify the air, and returns to the air heat absorption chamber 3 through the circulating water pump after reaching the bottom, completing the cycle.

[0034] In one embodiment, a demisting layer 2 17 is installed inside the flue gas heat release chamber 2 and above the flue gas heat exchange spray pipe 16, and a demisting layer 10 is installed inside the air heat absorption chamber 3 and above the air heat exchange spray pipe 6. Both the demisting layer 10 and the demisting layer 2 17 are made of metal mesh.

[0035] It should be noted that in this embodiment, after the flue gas passes through the spray pipe, liquid droplets (fog droplets) appear in the flue gas due to the temperature difference or humidity change. The fog droplets are effectively captured by the mesh structure of the second demisting layer to prevent a large amount of water from being carried out. When the air passes through the spray pipe for heating, fog droplets will also appear. The liquid droplets in the air are captured by the first demisting layer to prevent the excessive humidity from affecting the combustion-supporting effect.

[0036] In one embodiment, the air inlet and outlet channels include an air inlet 4 and an air outlet 9. The air outlet 9 is fixedly connected to one side of the air heat absorption chamber 3. The air inlet 4 is located below the air heat exchange portion 5. The air outlet 9 is fixedly connected to the outside of the smoke heat release chamber 2 and is located above the demisting layer 10.

[0037] It should be noted that, in this embodiment, the air enters the air heat absorption chamber 3 from the air inlet 4, and then passes through the air heat exchange part 5 from bottom to top. During this period, the air contacts and exchanges heat with the water sprayed from the air heat exchange spray pipe 6. The air contacts the hot water, so that the air is heated and humidified, and then discharged into the combustion chamber of the boiler through the air outlet 9.

[0038] In one embodiment, a second equalizing plate 13 is provided inside the smoke heat release chamber 2 and below the smoke inlet 14 , and a first equalizing plate 7 is fixedly connected inside the air heat absorption chamber 3 and below the air inlet 4 .

[0039] It should be noted that, in the present embodiment, the equalizing plate 13 is used to filter the water sprayed from the flue gas heat exchange spray pipe 16. The water contacts the flue gas inside the flue gas heat exchange part 15, and can also reduce dust during the cooling process. After the water reduces the large particles in the flue gas, it is filtered through the equalizing plate 13 to prevent the water from being discharged to other equipment through the water outlet pipe 12. The equalizing plate 17 is used to filter the impurities in the air under the water sprayed by the air heat exchange spray pipe 6, to prevent the large particles in the air from entering the flue gas heat release chamber 2 under the action of the circulating water pump 8 and the circulating water pipe 19.

[0040] In the description of the present invention, it is necessary to understand that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "front", "center", "both ends" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0041] In addition, the terms "first", "second", "third" and "fourth" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first", "second", "third" and "fourth" may explicitly or implicitly include at least one of such features.

[0042] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0043] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A composite single-tower system for heating and humidifying combustion air in a gas boiler, characterized in that: include: A tower body (1), the tower body (1) comprising a smoke heat release chamber (2) and an air heat absorption chamber (3) arranged above and below; A flue gas heat exchange unit (15), the flue gas heat exchange unit (15) is placed inside the flue gas heat release chamber (2), a flue gas inlet and outlet channel is arranged inside the flue gas heat release chamber (2), a flue gas heat exchange spray pipe (16) is arranged above the flue gas heat exchange unit (15), a pipe connection part is installed in the middle of the flue gas heat exchange spray pipe (16), which is used to mix boiler feed water with circulating water at the bottom of the air heat absorption chamber (3) and place the mixed mixture in the flue gas heat exchange spray pipe (16); An air heat exchange unit (5), the air heat exchange unit (5) is placed inside the air heat absorption chamber (3), an air inlet and outlet channel is provided inside the air heat absorption chamber (3), an air heat exchange spray pipe (6) is provided above the air heat exchange unit (5), a pressurized water pump (11) is installed at the end of the air heat exchange spray pipe (6) for injecting water after heat exchange in the flue gas heat release chamber (2) into the air heat exchange spray pipe (6) for secondary heat exchange.

2. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 1, characterized in that: The air heat exchange part (5) and the smoke heat exchange part (15) are both composed of a plurality of corrugated plates stacked one above the other.

3. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 1, characterized in that: The smoke inlet and outlet channel comprises a smoke inlet (14) and a smoke exhaust pipe (20); the smoke inlet (14) is fixedly connected to one side of the bottom of the smoke heat release chamber (2) and is located below the smoke heat exchange portion (15); the smoke exhaust pipe (20) is fixedly connected to the top of the smoke heat release chamber (2); and a rain cover (21) is installed on the top of the smoke exhaust pipe (20).

4. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 1, characterized in that: The pipeline connection part comprises a circulating water pipe (19) and a water supply inlet pipe (18), the water supply inlet pipe (18) and the circulating water pipe (19) are both connected to the flue gas heat exchange spray pipe (16), the bottom of the circulating water pipe (19) is connected to a circulating water pump (8), and the input end of the circulating water pump (8) is inserted into the interior of the air heat absorption chamber (3).

5. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 1, characterized in that: A water supply outlet pipe (12) for drainage is fixedly connected to the bottom of the smoke heat release chamber (2), and the input end of the pressure water pump (11) is connected to the middle of the water supply outlet pipe (12).

6. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 3, characterized in that: A second demisting layer (17) is installed inside the flue gas heat release chamber (2) and above the flue gas heat exchange spray pipe (16), and a first demisting layer (10) is installed inside the air heat absorption chamber (3) and above the air heat exchange spray pipe (6).

7. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 6, characterized in that: The demisting layer 1 (10) and the demisting layer 2 (17) are both made of metal mesh.

8. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 7, characterized in that: The air inlet and outlet passage comprises an air inlet (4) and an air outlet (9), wherein the air outlet (9) is fixedly connected to one side of the air heat absorption chamber (3), the air inlet (4) is located below the air heat exchange portion (5), and the air outlet (9) is fixedly connected to the outside of the smoke heat release chamber (2) and is located above the demisting layer (10).

9. A composite single-tower system for heating and humidifying combustion air in a gas boiler according to claim 8, characterized in that: A second equalizing plate (13) is provided inside the smoke heat release chamber (2) and below the smoke inlet (14), and a first equalizing plate (7) is fixedly connected inside the air heat absorption chamber (3) and below the air inlet (4).

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