JPH0621684B2 - Surface burning burner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention is provided with a large number of gas ejection holes on a burner surface,
The present invention relates to a surface combustion burner in which gas is ejected from the gas ejection holes to form a large number of minute flames on the ejection side for combustion, and in particular, a large number of minute flames generated on the burner surface are divided into desired surface areas. In addition, the present invention relates to a surface combustion burner designed to maintain combustion flame.

[Prior Art] As is well known, gas fuels such as city gas or LPG are used as industrial fuel sources in connection with environmental problems such as air pollution in that the harmful components in the combustion gas are extremely small. It tends to be used frequently. As a matter of course, when the gas fuel is used as the fuel source, the gas burner is applied to the gas combustion section of the equipment used. According to the above-mentioned tendency, in one example, gas fuel is also used for the boiler device, and accordingly, the number of boiler devices equipped with a gas burner is increasing.

As the gas burner for the boiler device, a blast type burner has been conventionally used, and in recent years, a kind of surface combustion burner is becoming popular.

This type of surface combustion burner is configured to eject a premixed gas through a burner element having a minute gap to cause a large number of minute fires on the surface of the burner element for combustion.

In the conventional surface combustion burner, for example, as shown in FIG. 16 and FIG. 17, the fuel gas is caused to flow out through a flame holder (32) having a large number of minute holes (31) formed, and the flame holder (32) is discharged. It is a type that forms many microflames on the surface of.

[Problems to be Solved by the Invention] By the way, in the surface combustion burner as described above, when the supply pressure of the premixed gas is increased in order to achieve high-load combustion, the fine holes (31) on the surface of the flame stabilizer (32) The jet speed of the premixed gas from the tank is increased, and the minute flame on the surface of the flame holder is
As shown in (1), they are integrated with each other, and finally become one flame extending from the surface of the flame stabilizer.

As is well known, the combustion reaction is performed in a region (α) where the ejection speed of the premixed gas and the combustion speed are balanced.

Therefore, in the above-mentioned conventional surface combustion burner, the combustion flame is integrated as the supply pressure of the premixed gas is increased, so that the combustion reaction region (α) is one flat as shown in FIG. 18C. It becomes planar. In this state, the combustion reaction region (α) is sandwiched with respect to the supplied premixed air-fuel ratio, the flame stability is poor, and combustion is accompanied by vibration. In particular, when the jet speed of the premixed gas changes due to the fluctuation of the supply pressure of the premixed gas, the above-mentioned balanced state is easily broken, and the flame is lifted or blown off. Further, at the time of ignition in this type of burner, the flame instantly spreads over the entire surface combustion burner, which causes a problem that the impact at the time of ignition is large.

As a means for solving this problem, a group in which a predetermined number of fine holes (31) are densely packed by arranging a lattice-like member having a predetermined number of window holes on the flame holder surface, etc. There is a surface combustion burner sectioned in. However, in this surface combustion burner, the lattice-like member expands due to combustion heat and bends in a direction away from the flame holder surface, and further, due to this bending deformation, it becomes easier to receive the heat of combustion and receives the heat of combustion. There is no denying the possibility that it will glow red and eventually burn out. In order to prevent such a temperature rise of the lattice-shaped member, an attempt has been made to cool the lattice-shaped member by providing a plurality of small holes on the entire surface of the lattice-shaped member and ejecting a premixed gas from these small holes. However, at present, there are some technical problems remaining in the realization of a surface combustion burner capable of stable combustion with a small size and high load combustion type.

Therefore, the present invention provides a surface combustion burner in which a large number of gas ejection holes are provided on the surface of a burner, a premixed gas is ejected from the gas ejection holes, and a large number of minute flames are formed on the ejection side for combustion. In this case, by providing a flame holding plate member on the ejection hole side of the burner surface, a large number of minute flames generated on the burner surface are divided into desired areas to provide a surface combustion burner for holding the combustion flame. Therefore, the present invention aims to solve the drawbacks and many problems found in the above-mentioned conventional example.

[Means for Solving the Problem] In order to achieve the above-mentioned object, the present invention is specifically to stack flat plates and corrugated plates alternately, and to place the corrugated plates between the flat plates and corrugated plates. Is provided with a large number of gas ejection holes extending along the wavy line, and the flat plate and the corrugated plate are aligned along a plane at both end edges intersecting with the wavy line of the corrugated plate, and the gas inlet end face and the gas A burner element having an ejection end face, wherein a premixed gas is ejected from the gas inlet end face side of the burner element through the gas ejection hole to the gas ejection end face side, and a large number of minute flames are present on the gas ejection end face side. In a surface combustion burner which is adapted to produce combustion, a plurality of flame retaining plate members for partitioning a large number of gas ejection holes on the gas ejection end face side into a plurality of gas ejection hole groups, Flame stabilization plate member is made of those having a first plate portion and second plate portions via the right-angle folding unit,
The first plate portion is sandwiched between a flat plate and a corrugated plate in the burner element, and the second plate portion is combined so as to cover a part of the gas ejection end surface. The second plate portion of 5 constitutes a surface combustion burner in which a large number of gas ejection holes on the gas ejection end face side are divided into a plurality of gas ejection hole groups.

[Operation] According to the surface combustion burner according to the present invention, the first plate portion of the flame holding plate member is sandwiched between the flat plate and the corrugated plate, and a part of the burner surface is formed into the second portion of the flame holding plate member.
By creating a vortex of the premixed gas on the downstream side of the second plate portion in the gas ejection direction by providing a cooling effect, preventing deformation due to heat and preventing burnout and the like due to this. To improve flame retention and durability.

[Examples of the Present Invention] The surface combustion burner according to the present invention will be described below in detail with reference to some specific examples shown in the drawings.

1 and 2 show a basic example of a surface combustion burner according to the present invention. The surface combustion burner in this example is constructed by alternately stacking a corrosion-resistant steel flat plate (1) and a corrosion-resistant steel corrugated plate (2) between the flat plate (1) and the corrugated plate (2). The corrugated plate
It includes a burner element (BE) having a large number of gas ejection holes (4) extending along the wavy line of (2). The burner element (BE) includes the flat plate (1) and the corrugated plate (2), and the corrugated plate (2).
Each end edge (1a), (2a) and (1b), (2b) intersecting the wavy line of
Are aligned along a plane, respectively, and form a gas inlet end surface (BE-A) and a gas ejection end surface (BE-B).
In addition, the burner element (BE) has the flat plate (1) and the corrugated plate (2) in the stacking direction of the flat plate (1) and the corrugated plate (2).
Are alternately laminated and shape-supported by the frame-like frame (3) to form a burner unit having a burner surface area L ₁ × L ₂ .

With such a laminated structure, the corrugated plates (2) do not come into close contact with each other, and the gas ejecting holes (4) along the corrugated line of the corrugated plate (2) are held with a space maintained by the flat plate (1). Can be formed in large numbers. For the burner element (BE), the premixed gas has a large number of gas ejection holes from the gas inlet end surface (BE-A).
It is ejected to the side of the gas ejection end face (BE-B) through (4).

On the other hand, the surface combustion burner according to the present invention comprises a combination of a flame holding plate member (5) with the burner element (BE). The flame holding plate member (5) is made of a metal material having excellent heat resistance and corrosion resistance, and basically, the first plate portion (7) and the second plate are formed via the bent portion (6) at right angles. And part (8). In the example shown in FIGS. 1 and 2, the flame holding plate member (5) is a plate body having a dimension L ₁ bent into an L-shaped cross section. The first plate portion (7) of the flame holding plate member (5) is substantially equal to the thickness dimension T of the burner element (BE), and the flat plate (1) and the corrugated plate (2) in the burner element (BE) are included. ) To form a cooling leg that is sandwiched between. On the other hand, the second plate portion (8) of the flame holding plate member (5) has a width W that covers a part of the gas ejection end surface (BE-B) of the burner element (BE) in a strip shape. There is. The flame holding plate member (5) is combined with the burner element (BE) in order to divide the surface area of the burner element of L ₁ × L ₂ in the direction of the dimension L ₂ with respect to the burner unit. A large number of gas ejection holes (4) on the end surface (BE-B) side are connected to a plurality of gas ejection hole groups (G ₁ ), (G
_It is divided into ₂ ) and (G ₃ ).

The surface-combustion burner having the above-mentioned configuration is burner element (BE) at the time of combustion, especially at low load combustion.
A minute flame is formed in each of the gas ejection holes (4) in the above. On the other hand, when the supply pressure of the premixed gas is increased, the flame is integrated with the flames of the adjacent ejection holes (4) to form a larger flame, but the flame holding plate member (5) causes the ejection holes (4) ) Is
It is divided into a plurality of groups (G ₁ ), (G ₂ ), and (G ₃ ), and the flame is divided for each group.

Therefore, even if the supply pressure of the premixed gas is increased and the combustion load is high, flames are independently formed in each group of the ejection holes (4), and the region that contributes to the combustion reaction more than the conventional one.
(α) spreads. Therefore, even if the jet speed of the premixed gas changes due to the fluctuation of the supply pressure of the premixed gas, the balanced state with the combustion speed is maintained, and even if the balanced state is broken,
It recovers easily and has stable combustion. Further, at the time of ignition, since flames are sequentially formed for each of the groups (G ₁ ), (G ₂ ), and (G ₃ ), ignition noise and impact can be suppressed to be small.

In the above combustion state, the flame holding plate member (5) in the surface combustion burner is heated mainly by receiving radiant heat from the combustion flame. However, in the surface combustion burner according to the present invention, the first plate portion (7) of the flame holding plate member (5) is replaced by the flat plate (1) of the burner element (BE).
And the corrugated plate (2), and a part of the burner surface is covered with the second plate part (8) of the flame holding plate member (5), and is placed on the downstream side of the second plate part in the gas ejection direction. The flame holding plate member (5) has a structure that causes the vortex of the premixed gas.
The flame holding plate member (5) by directly and indirectly cooling
Prevents thermal deformation of the product and burnout etc. due to the thermal deformation.

Further, the first plate portion (7) of the flame holding plate member (5).
Is held by the burner element (BE) and functions as a reinforcing member for the second plate portion (8), so that the thermal deformation of the second plate portion (8) is prevented It can be effectively prevented together with the cooling action.

Next, several different embodiments of the surface combustion burner according to the present invention will be described.

The surface combustion burner according to the second embodiment shown in FIGS. 3 and 4 is different from the surface combustion burner according to the first embodiment in that the flame holding plate member (5) is different. is there. That is, in the surface combustion burner according to the second embodiment, the flame holding plate member (5) has a plurality of gas ejection ports (9) with respect to the second plate portion (8). .
In the case of the first embodiment, if the width dimension W of the second plate portion (8) of the flame holding plate member (5) is increased for the purpose of improving the flame holding property, the cooling becomes insufficient. The bent second plate portion may be burnt out. As in the second embodiment, the second plate portion of the flame holding plate member (5)
With the gas jet port (9) provided in (8), a gas flow as shown in FIG. 4 is generated, and the cooling effect can be enhanced while maintaining the flame holding effect.

FIGS. 5, 6, and 7 show a surface combustion burner according to a third embodiment. In the surface combustion burner according to the third embodiment, when a plurality of flame holding plate members are combined with a burner element (BE) of one unit to form a plurality of gas ejection hole groups, each flame holding plate is formed. At the position of the member,
It consists of two flame-retardant plate members assembled back to back. A corrugated plate (3) is sandwiched between the pair of flame holding plate members (5) to form a premixed gas passage,
Achieves a cooling effect. In this embodiment, the flame holding plate member (5) may be provided with a gas ejection port (9) like the second embodiment.

FIGS. 8 and 9 show a surface combustion burner according to the embodiment of FIG. In the surface combustion burner according to the fourth embodiment, when the gas injection hole group is divided by the flame holding plate member (5) with respect to the burner element (BE) of one unit, the division size is divided into equal parts. It is a structural example. When the burner element (BE) is divided by the flame retaining plate member (5),
The flame in the center is heated from the flames on both sides, and the combustibility is improved. Therefore, if the flames in each part have almost the same size as in the case of equal division, the natural frequencies of the flames become close and resonance easily occurs ( Vibration and noise are generated during combustion, and the flame holding property and combustibility are not stable (so-called oscillatory combustion occurs). Therefore, as in the fourth embodiment, the natural frequency is dispersed by making the division ratios unequal, and the peak of resonance is lowered to solve the above problem. The division ratio is approximately 1: 8: 1 to 1: 1.
By selecting a range of about 3: 1, stable combustibility can be obtained. The above division ratio is obtained experimentally and is not limited to the range. The reason why the division ratio is selected in the above range is that, for example, if the division ratio is increased to 1: 20: 1, the flames on both sides become too small, and the flame temperature on both sides decreases (due to heat radiation to the surroundings). Therefore, the heating of the central flame becomes insufficient, and the flame holding property (combustibility) of the central flame and eventually the entire flame is not stable. Further, if the division ratio is so large, the flame in the center becomes too large, and there is no point in dividing the flame. On the other hand, even if the division ratio is close to 1: 1: 1, in addition to the above resonance, there is a problem in flame holding property. Furthermore, if the central portion is made smaller such that the split ratio is 1: 0.05: 1, the large flame (both sides) is not sufficiently heated by the small flame (center),
Because it can be regarded as burning with two large flames,
It will be equivalent to two equal divisions.

Next, still another embodiment of the present invention will be described with reference to FIGS.

In the drawing, (BE) is a burner element, and (20) is
4 shows a lattice-shaped flame holding plate member that divides a large number of gas ejection holes (14) of the burner element (BE) into a plurality of small groups.

In this embodiment, the burner element (BE) is a thin frame plate (11) and a corrugated plate (12) in a plate shape, and a frame-shaped frame (13) formed by laminating a large number of plates alternately in the thickness direction. It is a configuration that is held. With such a laminated structure,
The corrugated plates (12) can be laminated in a state in which the corrugated plates (12) are held in close proximity to each other without being in close contact with each other and are surrounded by the concave portion (12a) of the corrugated plate (12) and the flat plate (11). The region functions as a premixed gas ejection hole (14).

The flame holding plate member (20) of the lattice is, in this embodiment,
The burner element (BE) is formed integrally with the frame-like frame (13) and has a substantially square window hole (24) formed on the surface over a plurality of rows and a plurality of columns (4 rows and 3 columns in this example).
The ejection holes (14) are divided into a plurality of (12 in this example) small groups.

Vertical and horizontal crosspieces (21), (21) of the lattice-shaped flame holding plate member (20) ...
Of these, the three cross-pieces (21
In a), desired gaps (22) are formed along the longitudinal direction. Further, at both edges of the opening along the longitudinal direction of the gap (22), there are provided sheet metal cooling legs (23) extending toward the back side of the burner element (BE), and the legs (23) facing each other are provided. , (2
A spacer (corrugated plate in this example) (31) having a gap that does not prevent the flow of the air-fuel mixture is interposed between 3).

At the time of low load during combustion of the surface combustion burner configured as described above, a minute flame is formed in each of the ejection holes (14) exposed at each window hole (24) position of the flame holding plate member (20) of the lattice. (13th
(See Figure A).

Then, when the supply pressure of the premixed gas is increased, the flame is integrated with the flames of the adjacent ejection holes (14) to form a larger flame.However, due to the lattice-shaped flame holding plate member (20), the ejection is performed. The hole (14) is divided into a plurality of small groups A, B, C ... And each group A, B, C .. The flames do not unite.

Therefore, even if the supply pressure of the premixed gas is high and the combustion load is high, the flames will be discharged into the groups A, B, C of the ejection holes (14).
Each region is independently formed, and the region (α) contributing to the combustion reaction is expanded as compared with the conventional one. Therefore, even if the ejection speed of the premixed gas changes due to the fluctuation of the supply pressure of the premixed gas,
The balance with the combustion speed is maintained, and even if the balance is broken, it is easily recovered and stable combustion is performed.
Further, at the time of ignition, since flames are sequentially formed in each of the groups A, B, C ..., Ignition noise and impact can be suppressed to a small level.

In the above combustion state, the lattice-shaped flame holding plate member (20),
It is heated mainly by receiving radiant heat from the combustion flame. However, in the surface combustion burner according to the present invention, the cross section (2
The surface of the lattice-shaped flame-holding plate member (20) is directly cooled by the premixed gas ejected from the gap (22) provided in (1), and further these leg parts are reached until the gap (22) is reached. The premixture passing between (23) and (23) indirectly cools the surface of the flame holding plate member (20) of the lattice through these legs (23) and (23). for that reason,
It is possible to prevent thermal deformation of the lattice-shaped flame holding plate member (20), which has been a problem in the past, and burnout and the like due to this thermal deformation.

Furthermore, the leg portions (23) and (23) are the flame-retardant plate member (20) in the form of a lattice.
Since it functions as a reinforcing member, the lattice-shaped flame holding plate member (20) can be effectively prevented from being thermally deformed together with the cooling action of the premixed gas.

In the above description, the lattice-shaped flame holding plate member (20) is
All are formed by straight edges, but as shown in FIG. 14, cutouts (2
5), (25), etc. may be provided to absorb the strain due to thermal deformation. Further, although the flame holding plate member (20) of the lattice is formed integrally with the frame-shaped frame (13) of the burner element (BE), it may be provided separately.

Further, not limited to the above-described embodiment, for example, as shown in FIG. 15, a plurality of flat plates (11) and corrugated plates are provided on a frame-like frame (13) integrally having a flame-retardant plate member (20) in a lattice shape. A plurality of burner elements (BE) holding (12) are combined, with a spacer (31) sandwiched between the end faces of the frame-shaped frames (13) facing each other, and these burner elements (BE) are combined. It may be configured to be held by another frame-shaped frame (15) .In this case, the spacer (31) held between the burner elements (BE) is used to pre-mix the gas between the frame-shaped frames (15) and (15). With the distribution channel of the frame-shaped frame (15)
The side surface of this serves as the cooling leg (23).

[Advantages of the Invention] As described above, according to the surface combustion burner according to the present invention, the flame holding plate member is directly cooled by the premixed gas ejected from the gap provided in the crosspiece, and the gap is also reduced. By the premixture that flows between the cooling legs until it reaches, is indirectly cooled via this leg, so the above-mentioned adverse effects of heat can be suppressed to a small level, and the surface with extremely high thermal durability A combustion burner can be obtained. Therefore, the effect of dividing the flame into small groups by the flame holding plate member and improving the flame holding property can be realized even during high-load combustion, and the practicality and versatility of the surface combustion burner can be further improved.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a first embodiment of a surface combustion burner according to the present invention, FIG. 2 is a schematic side sectional view of the surface combustion burner shown in FIG. 1, and FIG. FIG. 4 is a schematic perspective view of a surface combustion burner according to a second embodiment, FIG. 4 is a schematic side sectional view thereof, and FIG. 5 is a schematic perspective view of a surface combustion burner according to a third embodiment. FIG. 6 is a schematic side sectional view thereof, FIG. 7 is a plan view thereof, FIG. 8 is a schematic side sectional view of a surface combustion burner according to a fourth embodiment, and FIG. 9 is a burner. The graph which shows the relationship of the abnormal noise and flame holding property with respect to the division ratio about the division of the surface, FIG. 10 is a plan view of the surface combustion burner according to the fifth embodiment, and FIG. 11 is a schematic side sectional view thereof. FIG. 12 is a partially enlarged perspective view thereof, and FIGS. 13A and 13B show flame states at low combustion and high combustion. FIG. 14 is a schematic side sectional view, FIG. 14 is a schematic perspective view showing the embodiment of FIG. 6, FIG. 15 is a schematic plan view showing the seventh embodiment, and FIG. 16 is a conventional surface. A plan view showing an example of a combustion burner, FIG. 17 is a side sectional view thereof, and FIGS. 18A to 18C are side sectional views for explaining a flame state. (1) ...... Flat plate (2) ...... Corrugated plate (3) ...... Frame frame (4) ...... Gas ejection hole (5) ...... Flame holding plate member (6) ...... Bent part (7) ...... 1st plate part (8) ... 2nd plate part (9) ... gas outlet (BE) ... burner element

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Sogabe 7 Horie-cho, Matsuyama-shi, Ehime Miura Industrial Co., Ltd. (56) References JP-A-3-213904 (JP, A)

Claims (1)

[Claims] 1. A flat plate and a corrugated plate are alternately laminated, and a large number of gas ejection holes extending along the corrugated line of the corrugated plate are provided between the flat plate and the corrugated plate, and the flat plate and the corrugated plate are provided. Is a burner element formed by aligning a gas inlet end surface and a gas ejection end surface along both ends of the corrugated plate along one plane, and the gas inlet end surface side of the burner element is formed. In the surface combustion burner configured to eject a premixed gas from the above through the gas ejection hole to the gas ejection end surface side and generate a large number of minute flames on the gas ejection end surface side for combustion, in the gas ejection end surface side A plurality of flame retaining plate members for partitioning the plurality of gas ejection holes into a plurality of gas ejection hole groups are included, and the flame retaining plate member includes a first plate portion and a second plate through a right-angled bent portion. Having a part and Consists of
The first plate portion is sandwiched between a flat plate and a corrugated plate in the burner element, and the second plate portion is combined so as to cover a part of the gas ejection end surface. 2. A surface combustion burner, characterized in that a large number of gas ejection holes on the side of the gas ejection end face are divided into a plurality of gas ejection hole groups by the second plate portion in the above.