CN212204593U - Flue gas waste heat utilization device of gas boiler - Google Patents

Abstract

The utility model relates to a boiler technical field especially relates to a gas boiler flue gas waste heat utilization equipment, including flue, primary heat exchanger and secondary heat exchanger, the flue is linked together and exports the flue gas in the furnace with the furnace of boiler body, and primary heat exchanger and secondary heat exchanger locate the flue in proper order along the flow direction of flue gas on, and primary heat exchanger draws the sensible heat of flue gas, and secondary heat exchanger draws the latent heat of flue gas. Set up two heat exchangers on the flue, draw the sensible heat of flue gas by primary heat exchanger earlier, can make the flue gas temperature reduce but guarantee that the flue gas temperature is higher than dew point temperature, prevent corroding when realizing flue gas waste heat utilization, reduce the temperature of flue gas below dew point temperature and draw the latent heat of flue gas by secondary heat exchanger again, from this, carry out the heat transfer of latent heat after the earlier sensible heat to the flue gas through the flue and draw, follow the principle of step heat transfer, can carry out the heat transfer with huge latent heat in the flue gas and draw, thereby show increase flue gas waste heat utilization ratio, improve boiler efficiency.

Description

Flue gas waste heat utilization device of gas boiler

Technical Field

The utility model relates to a boiler technical field especially relates to a gas boiler flue gas waste heat utilization equipment.

Background

The boiler is a heating device, which uses coal, biomass, oil or gas as fuel to produce heat through combustion to produce steam or hot water. Smoke and slag generated by coal pollute the environment and harm the health of people, and the combustion technology and the smoke treatment are complex; the oil-gas fuel is easy to transport and use, basically does not produce environmental pollution under the condition of ensuring good combustion, and has high calorific value. In recent years, gas (oil) boilers have been widely used due to their small size, high degree of automation, and convenient installation. Urban heating boilers consume a large amount of primary energy and emit a large amount of pollutants. The traditional heat supply boiler mainly uses fire coal as a main part, and with the improvement of the urban living standard, in order to improve the urban air quality, the use of clean energy has become a trend, and the natural gas boiler is greatly recommended to use.

In order to avoid low-temperature corrosion of a tail heating surface, the exhaust gas temperature of a traditional coal-fired heat supply boiler is usually higher than 150 ℃, the steam boiler is even as high as 200 ℃, after natural gas is adopted, the exhaust gas temperature of most of existing hot water boilers is 140-200 ℃, so that a large amount of energy is consumed, the operation cost of the boiler is improved, the exhaust gas temperature of the boiler taking the natural gas as the fuel can reach 150-250 ℃, and the boiler containing water vapor is about 15-19% (volume) and is a main carrier of the heat of the exhaust gas. If the temperature of the exhaust gas of the boiler is reduced to a sufficiently low level, the superheated water vapor in the exhaust gas is condensed to release latent heat of vaporization, and the boiler in which the latent heat of vaporization in the exhaust gas is recovered is called a condensing boiler. In the condensing boiler, the defects of low efficiency, easy corrosion of equipment, untimely waste heat utilization and the like exist in the traditional flue heat exchange design, so that the overall efficiency of the boiler is not high, and a large amount of energy is wasted.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is to provide a gas boiler flue gas waste heat utilization equipment can increase flue gas waste heat utilization rate, improve boiler efficiency to overcome prior art's above-mentioned defect.

In order to solve the technical problem, the utility model discloses a following technical scheme: the utility model provides a gas boiler flue gas waste heat utilization equipment, includes flue, primary heat exchanger and secondary heat exchanger, and the flue is linked together and exports the flue gas in the furnace with the furnace of boiler body, and on primary heat exchanger and secondary heat exchanger located the flue in proper order along the flow direction of flue gas, the sensible heat of flue gas was drawed to primary heat exchanger, and secondary heat exchanger draws the latent heat of flue gas.

Preferably, the furnace also comprises a primary air inlet pipe for inputting air into the furnace, and the primary air inlet pipe is communicated with the furnace after passing through the primary heat exchanger.

Preferably, the primary heat exchanger is a shell and tube heat exchanger.

Preferably, the secondary heat exchanger comprises a plurality of heat pipes, evaporation ends of the heat pipes are arranged in the flue, and condensation ends of the heat pipes are arranged outside the flue.

Preferably, the evaporation end of the heat pipe is V-shaped.

Preferably, the evaporation end of the heat pipe is made of corrosion-resistant ceramic material.

Preferably, the condensation end of the heat pipe is rectangular.

Preferably, the outer circumferential surface of the condensation end of the heat pipe is provided with a fin.

Preferably, the fin is spirally wound on an outer circumferential surface of the condensation end of the heat pipe.

Compared with the prior art, the utility model discloses the progress that has showing:

the utility model discloses a gas boiler flue gas waste heat utilization equipment, set up two heat exchangers on the flue, earlier by a heat exchanger and the flue gas heat transfer through the flue, draw the sensible heat of flue gas, can make the flue gas temperature reduce but guarantee that the flue gas temperature is higher than dew point temperature, prevent corroding when realizing flue gas waste heat utilization, carry out heat transfer cooling once more to the flue gas by secondary heat exchanger again, can reduce the temperature of flue gas to below dew point temperature and draw the latent heat of flue gas, therefore, utilize two heat exchangers to carry out the heat transfer of latent heat behind the earlier sensible heat to the flue gas through the flue and draw, follow the principle of step heat transfer, can carry out the heat transfer with huge latent heat in the flue gas and draw, thereby show increase flue gas waste heat utilization, boiler efficiency is improved.

Drawings

Fig. 1 is a schematic structural diagram of a flue gas waste heat utilization device of a gas boiler in an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a heat pipe in the flue gas waste heat utilization device of the gas boiler of the embodiment of the present invention.

FIG. 3 is a schematic view of a heat pipe condensation end in the flue gas waste heat utilization device of the gas boiler according to the embodiment of the present invention.

Wherein the reference numerals are as follows:

1. flue 2, primary heat exchanger

3. Secondary heat exchanger 30 and heat pipe

301. An evaporation end 302 and a condensation end

303. Fin 4 and boiler body

5. Hearth 6, primary air inlet pipe

Detailed Description

The following describes the present invention in further detail with reference to the accompanying drawings. These embodiments are provided only for illustrating the present invention and are not intended to limit the present invention.

In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

As shown in fig. 1 to 3, the present invention relates to an embodiment of a waste heat utilization device for flue gas of a gas boiler.

Referring to fig. 1, the gas boiler flue gas waste heat utilization device of this embodiment includes flue 1, primary heat exchanger 2 and secondary heat exchanger 3, and flue 1 is linked together and exports the flue gas in the furnace 5 with the furnace 5 of boiler body 4, and primary heat exchanger 2 and secondary heat exchanger 3 locate flue 1 in proper order along the flow direction of flue gas on, and primary heat exchanger 2 draws the sensible heat of flue gas, and secondary heat exchanger 3 draws the latent heat of flue gas.

The gas boiler flue gas waste heat utilization equipment of this embodiment, set up two heat exchangers on flue 1, earlier by heat exchanger 2 and the flue gas heat transfer through flue 1, draw the sensible heat of flue gas, can make flue gas temperature reduce but guarantee that flue gas temperature is higher than dew point temperature, prevent corroding when realizing flue gas waste heat utilization, again carry out heat transfer cooling once more to the flue gas by secondary heat exchanger 3, can reduce the temperature of flue gas to below dew point temperature and draw the latent heat of flue gas, therefore, utilize two heat exchangers to carry out the heat transfer of latent heat after earlier sensible heat to the flue gas through flue 1 and draw, follow the principle of step heat transfer, can carry out the heat transfer with huge latent heat in the flue gas and draw, thereby show increase flue gas waste heat utilization ratio, improve boiler efficiency.

Referring to fig. 1, preferably, the gas boiler flue gas waste heat utilization device of the present embodiment further includes a primary air inlet pipe 6 for inputting air into the furnace 5, the primary air inlet pipe 6 is communicated with the furnace 5 after passing through the primary heat exchanger 2, and the cool air flow is inputted into the primary air inlet pipe 6, absorbs sensible heat of the flue gas extracted by the primary heat exchanger 2 when passing through the primary heat exchanger 2, so as to preheat inlet air of the boiler, form a hot air flow, and is inputted into the furnace 5 for combustion. Therefore, the boiler inlet air is preheated by utilizing the sensible heat of the flue gas in the flue 1, and the utilization of the flue gas waste heat is realized.

In this embodiment, the primary heat exchanger 2 may be a shell-and-tube heat exchanger, which is simple and convenient, and can reduce the cost of the apparatus.

Referring to fig. 2, in the present embodiment, preferably, the secondary heat exchanger 3 may include a plurality of heat pipes 30, and the plurality of heat pipes 30 may be fixed side by side on a fixed bracket. The evaporation end 301 of the heat pipe 30 is disposed in the flue 1 for absorbing the latent heat of the flue gas in the flue 1. The condensation end 302 of the heat pipe 30 is disposed outside the flue 1 for transferring the latent heat of the flue gas to a waste heat utilization outside the flue 1. Therefore, the latent heat of the flue gas can be utilized by the waste heat utilization part outside the flue 1 through the extraction and heat exchange effects of the heat pipe 30 on the latent heat of the flue gas, namely, the further extraction and utilization of the waste heat of the flue gas can be realized. The waste heat utilization part outside the flue 1 can be any heat utilization device needing heat. In this embodiment, the number of the heat pipes 30 included in the secondary heat exchanger 3 is not limited, and may be selected and designed according to the actual working condition of the boiler.

Preferably, referring to fig. 2, in the present embodiment, the evaporation end 301 of the heat pipe 30 is V-shaped, and the opening and closing angle of the V-shaped evaporation end 301 is not limited. The evaporation end 301 of the heat pipe 30 is designed into a V shape, so that the phenomenon that the heat exchange of the evaporation end 301 is affected by the eddy generated when the flue gas in the flue 1 flushes the evaporation end 301 of the heat pipe 30 can be avoided, and the heat exchange performance of the heat pipe 30 is ensured.

Preferably, in the present embodiment, the evaporation end 301 of the heat pipe 30 is made of a corrosion-resistant ceramic material, so as to prevent the evaporation end 301 of the heat pipe 30 from being corroded at a low temperature after the heat pipe 30 extracts latent heat from the flue gas to lower the temperature of the flue gas to below the dew point temperature.

Preferably, referring to fig. 2, in the present embodiment, the condensation end 302 of the heat pipe 30 is rectangular, and the rectangular condensation end 302 is located outside the flue 1, so as to be advantageously matched with a waste heat utilization position outside the flue 1, so as to transfer heat to the waste heat utilization position. Therefore, in this embodiment, the rectangular condensation end 302 and the V-shaped evaporation end 301 form an inverted Y-shaped heat pipe 6, and the inverted Y-shaped heat pipe 6 has good heat extraction and heat exchange performance.

Further, referring to fig. 3, in the present embodiment, fins 303 are disposed on the outer peripheral surface of the condensation end 302 of the heat pipe 30, and heat exchange can be enhanced by the fins 303. Preferably, the fins 303 are spirally wound on the outer circumferential surface of the condensation end 302 of the heat pipe 30, so as to obtain the best heat exchange effect.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and replacements can be made without departing from the technical principle of the present invention, and these modifications and replacements should also be regarded as the protection scope of the present invention.

Claims (9)

1. The utility model provides a gas boiler flue gas waste heat utilization equipment, its characterized in that, includes flue (1), primary heat exchanger (2) and secondary heat exchanger (3), flue (1) is linked together and exports with furnace (5) of boiler body (4) flue gas in furnace (5), primary heat exchanger (2) with secondary heat exchanger (3) are followed the flow direction of flue gas is located in proper order on flue (1), primary heat exchanger (2) extract the sensible heat of flue gas, secondary heat exchanger (3) extract the latent heat of flue gas.

2. The gas boiler flue gas waste heat utilization device according to claim 1, further comprising a primary air inlet pipe (6) for inputting air into the furnace (5), wherein the primary air inlet pipe (6) is communicated with the furnace (5) after passing through the primary heat exchanger (2).

3. The gas boiler flue gas waste heat utilization device according to claim 1, characterized in that the primary heat exchanger (2) is a shell-and-tube heat exchanger.

4. The gas boiler flue gas waste heat utilization device according to claim 1, characterized in that the secondary heat exchanger (3) comprises a plurality of heat pipes (30), evaporation ends (301) of the heat pipes (30) are placed in the flue (1), and condensation ends (302) of the heat pipes (30) are placed outside the flue (1).

5. The gas boiler flue gas waste heat utilization device according to claim 4, wherein the evaporation end (301) of the heat pipe (30) is V-shaped.

6. The gas boiler flue gas waste heat utilization device according to claim 4, characterized in that the evaporation end (301) of the heat pipe (30) is made of corrosion-resistant ceramic material.

7. The gas boiler flue gas waste heat utilization device according to claim 4, wherein the condensation end (302) of the heat pipe (30) is rectangular.

8. The gas boiler flue gas waste heat utilization device according to claim 4, wherein fins (303) are provided on the outer circumferential surface of the condensation end (302) of the heat pipe (30).

9. The gas boiler flue gas waste heat utilization device according to claim 8, wherein the fins (303) are spirally wound on the outer circumferential surface of the condensation end (302) of the heat pipe (30).

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