Combustor and gas water heating equipment using same

Abstract

The utility model provides a combustor and gas water heating equipment using the combustor. The burner comprises a plurality of burner units arranged side by side in the longitudinal direction, each burner unit extends in the transverse direction perpendicular to the longitudinal direction and comprises a top wall which is provided with a plurality of fire holes and extends in a flat mode, and the top walls of the burner units define a burning plane together. The combustor further comprises a baffle arranged on the peripheral side of the combustion plane, and the baffle is at least provided with a first part and a second part which are adjacently connected with the two longitudinal sides of the combustion plane respectively and extend flatly. The combustor is provided with the baffle plate which extends flatly, so that the gap between the side wall of the shell of the heat exchanger and the peripheral side of the surface of the combustor is reduced, the supply quantity of secondary air passing through the gap is reduced, the supply quantity of primary air below a combustion plane is correspondingly increased, enough allowance is reserved for emission of nitrogen oxides, and the emission efficiency of the nitrogen oxides is improved. The combustor can meet the emission requirement of nitric oxide and meanwhile adapt to more gas source types.

Description

Technical Field

[0001] The present disclosure relates to the field of combustion equipment, and in particular to a burner with low nitrogen oxide emission, and a gas water heater using the burner. Background Art

[0002] Gas water heaters, such as gas water heaters or gas heating furnaces, are usually equipped with burners and heat exchangers. The burner generates exhaust gas during the combustion process and is discharged into the atmosphere. Exhaust gas usually contains components that have an impact on the human body and the atmosphere, such as carbon monoxide (CO) or nitrogen oxides (NOx, mainly NO and NO2). With the improvement of living standards and awareness of environmental protection, people are paying more and more attention to the emission of harmful gases in household gas appliances. Research and analysis have shown that the toxicity of nitrogen oxides is greater than that of carbon monoxide, and long-term emissions will cause two types of pollution to the atmosphere: acid rain and photochemical smog. The Chinese patent announcement CN209026812U previously applied for and authorized by the applicant discloses a water-cooled burner that can reduce the emission of nitrogen oxides by cooling and lowering the flame temperature. However, the burner is only suitable for liquefied gas source G31, while for other types of gas, such as liquefied gas source G30, it will cause nitrogen oxide emissions to exceed the standard. In view of this, it is necessary to improve the existing burners so that they can be applicable to more types of gas while meeting the nitrogen oxide emission standards. Summary of the invention

[0003] In order to overcome the problems existing in the related art, the present disclosure provides a burner and a gas water heater using the burner.

[0004] A first aspect of an embodiment of the present disclosure provides a burner, comprising a plurality of burner units arranged side by side in a longitudinal direction, each burner unit extending in a transverse direction perpendicular to the longitudinal direction, and comprising a top wall provided with a plurality of fire holes and extending in a flat manner, wherein the top walls of the plurality of burner units together define a combustion plane. The burner also comprises a baffle plate arranged on the circumference of the combustion plane, the baffle plate having at least a first portion and a second portion respectively adjacent to both longitudinal sides of the combustion plane and extending in a flat manner.

[0005] In some embodiments, the baffle further includes a third portion adjacent to one lateral side of the combustion plane, connected to the first and second portions, and extending in a flat manner.

[0006] In some embodiments, a plurality of hooks protruding upward are provided on the adjacent side of the baffle plate to the combustion plane; the baffle plate is adjacent to the lower side of the peripheral side of the combustion plane, and the plurality of hooks are hung on the combustion plane.

[0007] In some embodiments, the burner further comprises a fixing member arranged on the peripheral side of the combustion plane; the fixing member is adjacent to a lateral side of the combustion plane, and its longitudinal ends are respectively fixedly connected to the ends of the first and second parts of the baffle.

[0008] In some embodiments, the ends of the first and second parts of the baffle are both formed with fixing parts, which are vertically raised relative to the main bodies of the first and second parts; the fixing piece is modified to be adjacent to the upper side of the combustion plane.

[0009] In some embodiments, the first and second portions of the baffle are both flatly extended to define a first width and a second width, respectively, and the first width and the second width are both between 12 mm and 18 mm.

[0010] In some embodiments, the third portion of the baffle extends flat to define a third width, and the third width is between 12 mm and 18 mm.

[0011] In some embodiments, the burner further comprises a cooling water pipe passing through the plurality of burner units in a longitudinal direction.

[0012] A second aspect of the disclosed embodiment provides a gas water heater, comprising the burner and a heat exchanger. The bottom of the heat exchanger housing is open and is covered on the upper part of the burner to allow hot flue gas generated by combustion to pass through and transfer heat to its water exchange pipe. A first gap and a second gap are formed between a pair of longitudinal side walls of the heat exchanger housing and the first and second parts of the baffle, respectively.

[0013] In some embodiments, the sizes of the first gap and the second gap are both between 3 mm and 7 mm.

[0014] The technical solution provided by one or more embodiments of the present disclosure may include the following beneficial effects: since the burner is provided with a flat extending baffle, the gap between the side wall of the heat exchanger shell and the peripheral side of the burner surface is reduced, thereby reducing the secondary air supply through the gap, and at the same time, the primary air supply below the combustion plane is increased accordingly, thereby leaving sufficient margin for nitrogen oxide emissions, so that the burner can adapt to more types of gas sources while meeting the nitrogen oxide emission requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 is a schematic plan view of a gas water heater in one embodiment of the present disclosure, wherein a portion of the housing is removed to show a burner, a gas distribution rack and a heat exchanger disposed in the gas water heater;

[0017] Figure 2 yes Figure 1 A partial cross-sectional schematic diagram of a gas water heater is shown, which shows the matching relationship between the burner and the heat exchanger;

[0018] Figure 3 yes Figure 1 A three-dimensional schematic diagram of the burner and the gas distribution frame assembly shown;

[0019] Figure 4 yes Figure 3 A partial exploded perspective view of a burner and a gas distribution rack assembly;

[0020] Figure 5 yes Figure 3 A schematic side view of a burner is shown in FIG. DETAILED DESCRIPTION

[0021] The following will describe the various embodiments shown in detail in conjunction with the accompanying drawings. However, these embodiments do not represent all embodiments consistent with the present disclosure, and any structural, methodological, or functional changes made by a person of ordinary skill in the art based on these implementations are all included in the protection scope requested by the attached claims.

[0022] Gas water heating equipment can be a gas water heater that uses combustible gas as fuel, such as natural gas, city gas, liquefied gas, biogas, etc., which heats water by burning combustible gas to meet the user's domestic water needs, or it can be a gas heating furnace used for central heating.

[0023] Reference Figure 1 and Figure 2 A specific embodiment of the gas water heater of the present disclosure is shown, and the gas water heater 100 includes a housing 40, a burner 10 for burning a mixture of gas and air contained in the housing, an electrode assembly 20 associated with the burner 10 for ignition and flame detection, a heat exchanger 30, and a gas distribution frame 50. The housing 40 is generally in the shape of a rectangular parallelepiped, and can be formed by splicing a plurality of panels. Figure 1 and Figure 2In the illustrated embodiment, some panels are removed to show the internal structure of the device. The burner 20 is used to burn a mixture of gas and air to generate hot flue gas, which usually also contains carbon monoxide, carbon dioxide, and nitrogen oxides. In some embodiments, the burner 10 includes a plurality of burner units 11 arranged side by side in the longitudinal direction, and a gas distribution rack 50 can be disposed below the burner 10, on which a plurality of nozzles 51 corresponding to the plurality of burner units 11 are disposed. The gas can be sprayed out through the nozzles 51 of the gas distribution rack 50 by the control of a gas proportional valve (not shown), and enter the burner unit 11 together with the primary air to mix, and then the mixture of gas and air is ignited at the top of the burner unit 11; at the same time, part of the gas diffuses at the top of the burner and mixes with the surrounding secondary air before further combustion.

[0024] Mate Reference Figures 3 to 5 As shown, each burner unit 11 is roughly in the shape of an upright plate, which extends in a lateral direction perpendicular to the longitudinal direction. An airflow channel is arranged in each burner unit 11, and the bottom of the airflow channel corresponds to the corresponding nozzle 51 of the gas distribution frame 50. The gas and primary air are mixed in the airflow channel after entering. Each burner unit 11 has a flat top wall 111, and a plurality of fire holes (not marked) are distributed in the lateral direction on the top wall 111. The mixed mixture of gas and air burns in the fire holes on the top wall 111. The top walls 111 of several burner units 11 are all on the same plane, so that a combustion plane can be defined together. A cooling water pipe 12 is arranged near the combustion plane, which passes through each burner unit 11 in sequence in the longitudinal direction, and passes through these burner units 11 again in reverse order after turning back at the other end, so that the water flowing in the cooling water pipe 12 helps to cool the combustion flame, thereby reducing the emission of nitrogen oxides to reduce pollution to the environment.

[0025] The burner 10 also includes a baffle 13 arranged on the peripheral side of the above-mentioned combustion plane. The peripheral side here refers to one or more sides around the combustion plane. In some embodiments, the baffle 13 has at least a first part 131 and a second part 132 respectively adjacent to the longitudinal sides of the combustion plane and extending in a flat manner. In this embodiment, the baffle 13 also includes a third part 133 adjacent to a lateral side of the above-mentioned combustion plane, integrally connected to the first part 131 and the second part 132, and extending in a flat manner. In some embodiments, the side adjacent to the baffle and the above-mentioned combustion plane is provided with a plurality of hooks 134 protruding upward. As Figure 4 As shown, these hooks 134 can be formed on the inner edges surrounded by the first part 131, the second part 132, and the third part 133, respectively, and can be formed by stamping out from the inner edge of the baffle and bending upward. When installed, the baffle 13 is adjacent to the lower side of the combustion plane, and the hooks 134 are hung on the combustion plane. Figure 2 and Figure 5 As shown, the top of the inner side (opposite side) edge of the first part 131 and the second part 132 of the baffle 13 abuts against the bottom of the outer side edge of the top wall of the two burner units 11 located on both sides in the longitudinal direction, and the top of the inner side edge of the third part 133 of the baffle 13 abuts against the bottom of the lateral side edge of the top wall of several burner units 11; several hooks 134 of the baffle 13 abut against the top wall edge of the corresponding burner unit 11; so that the baffle 13 is reliably positioned on the peripheral side of the combustion plane of the burner. In some embodiments, the baffle 13 can be further directly fixed to part of the burner unit 11 by means of screws or rivets, but in these embodiments, some of the burner units need to be appropriately modified, thereby reducing the versatility of the burner units.

[0026] In some embodiments, the burner further comprises a fixing member 14 disposed on the periphery of the combustion plane. In some embodiments, the fixing member 14 is adjacent to one lateral side of the combustion plane, and its longitudinal ends are respectively fixedly connected to the ends of the first and second parts of the baffle. Figures 3 to 5 In the illustrated embodiment, the ends of the first part 131 and the second part 132 of the baffle are both formed with fixing parts 135, which are bent upward from the main bodies of the first part 131 and the second part 132 and extend flatly, so that they are vertically lifted relative to the main bodies of the first part 131 and the second part 132, so that the fixing parts 135 can be flush with the combustion plane. The fixing member 14 is in the shape of an elongated strip, and through holes are formed on both longitudinal ends 141 and the fixing part 135. When installed, the fixing member 14 is adjacent to the upper side of the peripheral side of the combustion plane. In some embodiments, the fixing member 14 is arranged on the lateral side of the combustion plane opposite to the side where the third part 133 of the baffle is located, that is, on the same side of the combustion plane as the electrode assembly 20; it abuts against the upper lateral edge of the top wall 111 of a plurality of burner units, so that the baffle 13 can be firmly connected to the fixing member 14 by screws or rivets 15, so that the baffle can be reliably fixed relative to the burner unit 11. In this way, there is no need to modify some of the burner units 11. Reference Figure 5 As shown, the first portion 131 and the second portion 132 of the baffle plate are both flatly extended to define a first width W1 and a second width W2 beyond the combustion surface, respectively. In some embodiments, the first width W1 and the second width W2 are both between 12 and 18 mm, such as 12, 15, or 18 mm. In some embodiments, the third portion 133 of the baffle plate is also flatly extended to define a third width beyond the combustion surface, and the third width is also between 12 and 18 mm, such as 12, 15, or 18 mm.

[0027] In some embodiments, the heat exchanger 30 may be a fin-tube heat exchanger, that is, a plurality of fins are arranged in the heat exchanger housing 31, and a hot water exchange pipe (not shown) passes through the fins in a circuitous manner. The heat carried by the hot flue gas generated by the combustion is absorbed by the fins and further transferred to the water flowing through the hot water exchange pipe. The heated water is discharged through the pipe, thereby providing users with hot water required for life and / or heating. Figure 2 As shown, the shell 31 of the heat exchanger is open at the bottom and is covered on the upper part of the burner 10. A first gap G1 and a second gap G2 are formed respectively between a pair of opposite side walls of the heat exchanger shell 31 located in the longitudinal direction and the first part 131 and the second part 132 of the baffle. In some embodiments, the sizes of the first gap G1 and the second gap G2 are both between 3 and 7 mm, such as 3, 5, or 7 mm. In some embodiments, a third gap is also formed between the side wall of the heat exchanger shell 31 located on one side in the transverse direction and the third part 133 of the baffle, and the size of the third gap is also between 3 and 7 mm, such as 3, 5, or 7 mm. The above gap allows secondary air to pass through so as to further burn with the gas on the combustion plane. Since the burner is provided with a flat extending baffle, the gap between the side wall of the heat exchanger shell and the peripheral side of the burner surface is reduced, thereby reducing the secondary air supply through the gap, and at the same time increasing the primary air supply below the combustion plane accordingly, thereby leaving sufficient margin for nitrogen oxide emissions, so that the burner can adapt to more gas source types, such as liquefied gas G30, while meeting the nitrogen oxide emission requirements.

[0028] The following is a comparison of the data obtained from the nitrogen oxide emission test of gas water heaters using the burners before and after the improvement according to the requirements of Section 6.9.3 of the European standard EN26-2015 "Gas-fired instantaneous water heaters for the production of domestic hot water" on nitrogen oxide emission testing.

[0029] The test conditions are:

[0030] Type of liquefied gas source: G30;

[0031] Ambient temperature: 23℃;

[0032] Ambient air pressure: 1020mbar;

[0033] Relative humidity: 40%;

[0034] Rated heat load: 20.00kW, minimum heat load: 7.3kW.

[0035] The test data of the gas water heater using the existing burner (without baffle) is as follows. The nitrogen oxide emission obtained after weighted calculation is 76 mg / (kW·h).

[0036]

[0037] The test data of the gas water heater using the improved burner (in the above embodiment) are as follows. The nitrogen oxide emission obtained after weighted calculation is 70 mg / (kW·h).

[0038]

[0039] It can be seen from the comparison of the above test data that compared with the prior art, the gas water heater using the burner of the above embodiment has reduced nitrogen oxide emissions. According to the requirements of the Energy Related Products Directive (ErP Directive) implemented in Europe since September 2018, the emission limit of nitrogen oxides for water heaters using natural gas as the gas source shall not exceed 56 mg / (kW·h), and the emission of nitrogen oxides for water heaters using liquefied gas G30 as the gas source shall not exceed 72.8 mg / (kW·h) (i.e. the above emission limit multiplied by a coefficient of 1.3). Obviously, the gas water heater using the existing burner cannot be applied to liquefied gas G30 because its nitrogen oxide emissions cannot meet the requirements of the ErP Directive; while the gas water heater using the burner in the above embodiment can meet the requirements of the ErP Directive on nitrogen oxide emissions when using liquefied gas G30 and G31, that is, the gas source of the improved burner has a wider range of application, the reason is: by reasonably optimizing the supply of primary air and secondary air, the combustion performance is improved, and the design margin is increased.

[0040] In the description of the above-mentioned embodiments in the present disclosure, the orientations or positional relationships indicated by "longitudinal", "lateral", "vertical", "radial", "circumferential", "horizontal", "length", "width", "thickness", "up", "down", "left", "right", "front", "rear", etc. are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of description and simplification of 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 disclosure.

[0041] In the above disclosure, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the definition of "first", "second", etc. can explicitly or implicitly include at least one of the features. In the above description, the meaning of "several", "multiple", and other similar terms is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0042] In the above disclosure, unless otherwise clearly specified and limited, the terms "installed", "adjacent", "connected", "connected", "fixed" and the like 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 directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this disclosure can be understood according to specific circumstances.

[0043] In the above disclosure, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first feature is in direct contact with the second feature, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above", "above", or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below", or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0044] It should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A burner, comprising a plurality of burner units arranged side by side in a longitudinal direction, each burner unit extending in a transverse direction perpendicular to the longitudinal direction, and comprising a top wall provided with a plurality of fire holes and extending in a flat manner, wherein the top walls of the plurality of burner units together define a combustion plane; characterized in that: The burner further comprises a baffle plate arranged on the peripheral side of the combustion plane, wherein the baffle plate comprises at least a first portion and a second portion which are respectively adjacent to two longitudinal sides of the combustion plane and extend in a flat manner.

2. The burner according to claim 1, characterized in that: The baffle further includes a third portion which is adjacent to one lateral side of the combustion plane, connected to the first and second portions, and extends in a flat manner.

3. The burner according to claim 1 or 2, characterized in that: The adjacent side of the baffle plate and the combustion plane is provided with a plurality of hooks protruding upward; the baffle plate is adjacent to the lower side of the peripheral side of the combustion plane, and the plurality of hooks are hung on the combustion plane.

4. The burner according to claim 3, characterized in that: The burner also includes a fixing member arranged on the peripheral side of the combustion plane; the fixing member is adjacent to one lateral side of the combustion plane, and its longitudinal ends are respectively fixedly connected to the ends of the first and second parts of the baffle.

5. The burner according to claim 4, characterized in that: The ends of the first and second parts of the baffle are both formed with fixing parts, and the fixing parts are vertically raised relative to the main bodies of the first and second parts; the fixing parts are adjacent to the upper side of the peripheral side of the combustion plane.

6. The burner according to claim 1, characterized in that: The first and second portions of the baffle are both flatly extended to define a first width and a second width, respectively, and the first width and the second width are both between 12 mm and 18 mm.

7. The burner according to claim 2, characterized in that: The third portion of the baffle extends flat to define a third width, and the third width is between 12 mm and 18 mm.

8. The burner according to claim 1, characterized in that: The burner further comprises a cooling water pipe which passes through the plurality of burner units in the longitudinal direction.

9. A gas water heater, characterized in that: The equipment includes: A burner as claimed in any one of claims 1 to 8; and The heat exchanger has an opening at the bottom of its shell and is covered on the upper part of the burner to allow the hot flue gas generated by the combustion to pass through and transfer heat to its heat exchange water pipe; a first gap and a second gap are respectively formed between a pair of longitudinal side walls of the heat exchanger shell and the first part and the second part of the baffle.

10. The gas water heater according to claim 9, characterized in that: The sizes of the first gap and the second gap are both between 3 mm and 7 mm.

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