JP2001280604A - Combination oil and gas burner and exhaust gas treating device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure high power irrespective of the lowering of the calorific value of a gas and stoppage of the supply of the gas whose calorific value varies within a low level range. SOLUTION: A small diameter sleeve 3 for forming a vent path is disposed in a large diameter sleeve 2 which is located on a wall surface of a combustion chamber 1, being supported by a stay 4. A burner gun 5 for ejecting a town gas (13A) is provided to a portion corresponding to the axial core of the cylinder of the sleeve 3. A primary swirler 7 for causing a swirling flow for stabilizing flames is disposed at the tip of the burner gun 5. Ten burner nozzles 8 for ejecting digestion gas are dispersedly provided around the swirler 7. There is also provided an air supply path R for supplying combustion air to the burner gun 5 and the burner nozzles 8. Thus irrespective of the variation of the calorific value of the digestion gas, combustion is performed with a stable output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for storing organic waste such as sewage sludge, slag discharged from a beer factory, effluent from a candy factory, and garbage discharged from households in a digestion tank. Digestion gas generated during digestion treatment in anaerobic atmosphere, blast furnace gas (BFG) generated during operation of blast furnace, coke oven gas (COG) generated during operation of coke oven, converter generated during operation of converter Gas (L
A co-firing burner in which low-calorie, calorie-varying gas such as by-product gas such as DG) is mixed with a main fuel gas having a constant calorie such as city gas (13A) or liquefied natural gas (LPG) to burn. And an exhaust gas treatment apparatus using the same.

[0002]

2. Description of the Related Art As a co-burning burner as described above, there has been one disclosed in Japanese Patent No. 2857101. According to this conventional example, a heavy oil burner gun provided with an atomizer and a swirler at its tip is provided at the center of the combustion device. A ring surrounding the heavy oil burner gun,
Gas spokes (COG spokes) for low calorie gas, which are relatively difficult to burn, are provided.

[0003] Around a gas spoke outlet, a burner tile is provided as ignition means made of a refractory material. In addition, a split jet of air divided into a plurality in the circumferential direction and a split jet for low-calorie gas, which is more difficult to burn than the low-calorie gas, are alternately arranged in a ring shape on the outer periphery adjacent to the jet outlet of the gas spoke. An annular spoke (BFG spoke) is provided.

[0004] A wind box is provided surrounding the annular spokes, the wind box being communicated on the one hand to a central annular portion via a conduit traversing the annular spokes and the other to an outer peripheral passage portion. As a result, the combustion air flows from the wind box into the two parts, and is blown out from the burner tip to contribute to combustion.

[0005] With the above configuration, COG is spouted from the gas spokes around the swirler, ignited by the heavy oil flame formed inside the swirler, and ignited, after which combustion is continued. . At the beginning of the combustion, the burner tile acts as an ignition wall by being heated by the heavy oil flame, assists the ignition and combustion of the COG, and is also heated by the combustion flame of the COG, and assists the combustion of the COG by radiant heat.
Combustion is stabilized and continued.
In addition, BFG, which burns poorer than COG, mixes quickly with air when it comes out of the annular spokes and burns.

[0006]

However, in a heavy oil burner gun as in the above-mentioned publication, the turndown ratio (throttle ratio) is about 1 to 3. For this reason, when the calorie of COG is reduced or the supply is stopped, there is a limit to the supply amount of heavy oil that increases to compensate for the reduced calorie. As a result, there has been a problem that a high output cannot be set when a constant burner output is required regardless of COG calorie fluctuation.

[0007] The present invention has been made in view of such circumstances, and a co-firing burner according to the first aspect of the present invention is:
Regardless, such as degradation or outages calories gas calorie fluctuates low calorie, aims to allow a high output can be secured, multi-fuel burner of the invention according to claim 2, nitric oxide gas NO _X It is an object of the present invention to reduce it by reducing it to nitrogen gas. Further, a mixed burning burner of the invention according to claim 3 aims to enable good combustion of gas with low calories and varying calories,
The mixed combustion burner according to the invention according to claim 4 is characterized in that a nitrogen oxide gas
It is an object of the present invention to reduce _X , and an object of the present invention is to provide an exhaust gas treatment apparatus capable of effectively reducing a nitrogen oxide gas NO _X in combustion exhaust gas.

[0008]

According to a first aspect of the present invention, there is provided a co-firing burner, comprising: a burner gun for discharging a main fuel gas having a constant calorie; A swirler that generates a swirling flow for flame stabilization, a burner nozzle that is provided around the swirler or that is provided in an annular shape and that emits a low-calorie, calorie-varying gas, and a burner nozzle that burns the burner nozzle and the burner gun. And an air supply path for supplying the air.

According to a second aspect of the present invention, there is provided a co-fired burner according to the first aspect of the present invention, in which the tip of the burner gun is projected beyond the swirler in the co-fired burner according to the first aspect of the present invention, and the burner nozzle burns. The main fuel gas from the burner gun is supplied during the flame to be generated so that the nitric oxide gas can be reduced.

According to a third aspect of the present invention, there is provided a co-firing burner, wherein the air supply passage in the co-firing burner according to the first or second aspect of the present invention is provided around the burner nozzle. A primary air supply passage provided on a side far from the burner gun to supply primary air for combustion,
And a secondary air supply passage provided on the burner gun side around the burner nozzle to supply secondary air for combustion.

According to a fourth aspect of the present invention, there is provided a co-firing burner according to the third aspect of the present invention, wherein the co-firing burner according to the third aspect of the present invention is provided inside the combustion chamber on a side far from the burner gun around the burner nozzle. An exhaust gas recirculation flow path for sucking and recirculating the discharged exhaust gas is provided, and the exhaust gas is supplied to the burner nozzle in addition to the primary air.

[0012] Further, the exhaust gas treatment apparatus of the invention according to claim 5 achieves the above-mentioned object by providing claim 1,
The mixed combustion burner according to any one of claims 2, 3 and 4 is used to supply combustion exhaust gas from a gas turbine and / or a gas engine as air for combustion.

[0013]

According to the first aspect of the present invention, a burner gun is provided so as to jet a main fuel gas having a constant calorie, and a swirler is provided at a tip of the burner gun to reduce calories with low calories. A burner nozzle that ejects a fluctuating gas is dispersed or annularly provided around the swirler, and promotes mixing of the gas supplied from the burner nozzle dispersed or annularly provided around the swirler with combustion air. By delaying the mixing of the main fuel gas supplied from the burner gun with the air, it is possible to burn low calorie and fluctuating calorie gas by holding the flame with a swirler. Further, even if the supply of gas from the burner nozzle is stopped, only the main fuel gas ejected from the burner gun can be burned.

According to the configuration of the co-firing burner according to the second aspect of the present invention, the main fuel gas is supplied during the low calorie and calorie-varying gas flame which is supplied from the burner nozzle and burned by the flame holding of the swirler, Nitrogen oxide gas NO _{x in the} flame is produced by methane CH ₃ which is a component of the main fuel gas.
Can be reduced.

According to the third aspect of the present invention, the combustion air is supplied to the burner nozzle from both the side far from the burner gun and the burner gun to burn the gas having a low calorie and a variable calorie. .

According to the configuration of the mixed combustion burner of the present invention, the combustion exhaust gas discharged into the combustion chamber is sucked and recirculated, and the combustion exhaust gas is added to the primary air and supplied to the burner nozzle for combustion. .

The operation of the exhaust gas treating apparatus according to the fifth aspect of the present invention is as follows. Focusing on the fact that the residual oxygen concentration in the flue gas from gas turbines and gas engines is relatively high at about 15%, the flue gas from gas turbines and gas engines is used as combustion air for co-firing burners. I do.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partially cutaway front view of a co-firing burner according to a first embodiment of the present invention, FIG. 2 is a right side view, and FIG. 3 is a left side view. The small diameter sleeve 3 is supported by the support stay 4 to form a co-fired burner 5, and the co-fired burner 5 is provided on a wall surface of the combustion chamber 1.

A burner gun 6 for ejecting city gas (13A) as a main fuel gas having a constant calorie is provided so as to be located at a position corresponding to the cylinder axis of the small-diameter sleeve 3, and a city gas supply pipe 6a is provided in the burner gun 6. It is connected.

At the tip of the burner gun 6, a primary swirler 7 for generating a swirling flow for flame stabilization is attached, and is dispersed around the primary swirler 7 to remove digestive gas as a gas having a low calorie and varying in calories. There are ten burner nozzles 8 that jet out.

A secondary swirler 9 for generating a swirling flow for flame stabilization is provided on the outer peripheral surface on the distal end side of the small diameter sleeve 3. The burner nozzle 8 has a manifold 10
The digestion gas supply pipe 11 is connected via the. 1 in the figure
Reference numeral 2 denotes a pilot burner.

A wind box 13 of the co-firing burner 5 has a primary air inlet 14 for supplying air as combustion air or turbine exhaust gas to the burner gun 6 and the burner nozzle 8, and a large-diameter sleeve 2 and a small-diameter sleeve 3. A secondary air supply port 15 for supplying turbine exhaust gas is provided. R in the figure is
2 shows an air supply path for supplying combustion air.

Burner tile 1 constituting the wall of combustion chamber 1
6, bypass ports 17 are formed in a ring shape, and three tertiary air supply ports 18 that supply turbine exhaust gas to the bypass ports 17 are provided.

Although not shown, an air supply pipe is connected to each of the primary air supply port 14, the secondary air supply port 15, and the tertiary air supply port 18 through an opening / closing damper, and only air is supplied from the primary air supply port 14. State, a state in which the turbine exhaust gas is supplied from the primary air supply port 14 and the secondary air supply port 15, the primary air supply port 1
It is configured to be able to switch to a state in which the turbine exhaust gas is supplied from the fourth and second supply ports 15 and the desired number of the third supply ports 18.

FIG. 4 is a front view of a main part of a co-firing burner according to a second embodiment of the present invention. The difference from the first embodiment is as follows. The tip of the burner gun 6 is protruded from the primary swirler 7 so that the main fuel gas from the burner gun 6 can be supplied into the flame burned by the burner nozzle 8 to reduce the nitrogen oxide gas. That is,
CH ₄ + 2NO ₂ → CO ₂ + 2H ₂ O + N ₂ can be reacted with reduction treatment. The other configuration is the same as that of the first embodiment, and the description thereof will be omitted by retaining the same reference numerals.

The protruding amount of the tip of the burner gun 6 is represented by 2a ≧ L ≧ a / L where the protruding amount is L and the length from the center of the burner gun 6 to the center of the burner nozzle 8 is a.
It is good to set to 10. Burnagan 6 after 2a
Has the disadvantage of burning in. On the contrary, if it is less than a / 10,
This is because the main fuel gas burns before being supplied into the flame. Preferably, a ≧ L ≧ a / 5.

FIG. 5 is a partially cutaway side view showing a co-firing burner according to a third embodiment of the present invention, and FIG. 6 is a view taken along line AA of FIG. A small-diameter sleeve 23 for forming a passage is supported by a support stay 24 to form a co-firing burner 25, and the co-firing burner 25 is connected to the combustion chamber 1.
Is provided on the wall.

A burner gun 26 for jetting city gas (13A) as a main fuel gas having a constant calorie is provided so as to be located at a position corresponding to the cylinder axis of the small-diameter sleeve 23,
A city gas supply pipe 27 is connected to the burner gun 26.

A swirler 28 for generating a swirling flow for flame stabilization is attached to the tip of the burner gun 26. Ten burner nozzles 29 are provided around the swirler 28 and emit a digestive gas as a low-calorie and calorie-varying gas. The digester gas supply pipe 30 is connected to the burner nozzle 29.

An annular primary air supply passage R1 for supplying primary air for combustion is provided between the small diameter sleeve 23 and the burner nozzle 29. The support stay 24 is formed of a hollow pipe and is configured to also serve as an air supply pipe, so that air is supplied to the primary air supply path R1 through the support stay 24. Burner gun 26 and burner nozzle 2
9, an annular secondary air supply path R2 for supplying secondary air for combustion is provided.

The inside of the combustion chamber 1 of the small-diameter sleeve 23 is formed in an outwardly expanding cone shape, and the furnace wall portion 1a of the combustion chamber 1 facing the outerly expanding portion 23a is also formed in a cone shape. Thereby, the outer expanding portion 23a
An exhaust gas recirculation flow path R3 is formed between the inner wall surface of the large-diameter sleeve 22 and the outer peripheral surface of the small-diameter sleeve 23 so as to be continuous with the primary air supply path R1 from between the furnace wall portion 1a and the combustion chamber. The exhaust gas is recirculated and burned, and the nitrogen oxide gas N
The O _X is adapted to reduce.

Next, a digestion gas combustion treatment system to which an exhaust gas treatment device constituted by using the co-firing burner 5 of the first embodiment is applied will be described. FIG. 7 is an overall schematic configuration diagram showing a digestion gas combustion processing system, in which a generator 33 is connected to an output shaft 32 of a gas turbine 31 to drive the gas turbine 31 using city gas as fuel and to connect the generator 33 It is configured to drive to obtain generated power.

The co-firing burner 5 is provided at the subsequent stage of the gas turbine 31, and is configured to supply the high-temperature exhaust gas from the gas turbine 31 to the co-firing burner 5. Further, a digestion tank 35 is connected to the co-firing burner 5 via a digestion gas supply pipe 11 with a booster 34 interposed therebetween, and the co-firing burner 5 converts the digestion gas generated in the digestion tank 35 and the high-temperature exhaust gas from the gas turbine 31. The exhaust gas treatment device is configured to supply the waste gas to the gas turbine, burn the digestion gas, and burn the high-temperature exhaust gas from the gas turbine 31. In addition, mixed burner 5
Is connected to a city gas supply pipe 6a.

The digestion tank 35 has a hermetically closed structure that is closed from the outside air, and stores organic waste such as sewage sludge, slag discharged from a beer factory, waste liquid from a candy factory, and garbage discharged from households. It is configured to be digested by anaerobic bacteria in an anaerobic atmosphere. In this digestion treatment, organic substances are decomposed by anaerobic bacteria, and a digestive gas containing a large amount of methane gas is generated.

A centrifugal dehydrator 36 is connected to the digestion tank 35, and a sludge drying device 37 is connected to the centrifugal dehydrator 36 to dewater the digested sludge. They are dried to reduce their weight, and finally are incinerated or landfilled as industrial waste. A heating device 38 is provided around the digestion tank 35 to raise the temperature in the tank to a predetermined high temperature to promote digestion treatment of organic waste.

A boiler 40 is connected to the co-firing burner 5 via an exhaust gas supply passage provided with a heat exchanger 39 so that steam is generated by using the high-temperature exhaust gas discharged along with the combustion of the digestion gas as a heat source. Has become. Reference numeral 41 in the figure denotes a chimney for discharging exhaust gas passing through the boiler 40.

A steam turbine 43 is operatively connected to the generator 33 via a centrifugal clutch 42.

The sludge drying device 37 is connected to the boiler 40 via a first steam pipe 44, and also via a first steam pipe 44 and a second steam pipe 45 connected to an intermediate point thereof. A heating device 38 is connected so that energy can be effectively used.

The boiler 40 and the steam turbine 43 are connected to a third steam pipe 46 passing through the heat exchanger 39 via a return pipe 48 provided with a condenser 47. The steam is supplied to the steam turbine 43 via the heat exchanger 39, and the steam from the steam turbine 43 is supplied to the condenser 4
It is configured to return to the boiler 40 via 7.
Although not shown, steam from the boiler 40 is sent to a hot water supply facility, or to a heating facility or an absorption refrigerator to be used for air conditioning such as heating and cooling.

Although not shown, the city gas supply pipe 6a is provided with a flow control valve, and the digestion gas supply pipe 11 is provided with an open / close valve. Further, an air supply pipe (not shown) to the primary air supply port 14 (see FIG. 1), and the primary air supply port 14 (see FIG. 1), the secondary air supply port 15 (see FIG. 1) and 3
A damper is interposed in each exhaust gas supply pipe (not shown) to each of the tertiary air supply ports 18 (see FIG. 1).

Although not shown, the digestion gas supply pipe 11 has
A calorie meter for measuring the calorie of digestive gas (methane content in digestive gas) is attached, and the calorie meter is connected to a control device (microcomputer) and the control device is connected to a flow control valve of the city gas supply pipe 6a. It is connected and configured to automatically adjust the opening of the flow control valve according to the calories measured by the calorie meter.

That is, the control device increases the supply amount of city gas to be supplemented when the calorie of digestive gas is low, and decreases the supply amount of city gas to be supplemented when the calorie of digestive gas is high. When the operation of the digestion tank 35 is stopped at night or the like and the digestion gas is not supplied, only the city gas can be supplied.

According to the above-described configuration, only the shortage of calories is supplemented with the city gas regardless of the variation in the calories of the digestion gas supplied to the co-firing burner 5, and only the city gas is supplied even if the supply of the digestion gas is stopped. Supply and gas turbine 31
Burner 5 using turbine exhaust gas from combustion as combustion air
The steam is generated by the boiler 40 and steam is generated by the boiler 40, so that hot water supply and air conditioning such as heating and cooling can be stably performed.

When the gas turbine 31 is normally driven, the turbine exhaust gas is co-fired from the primary air supply port 14 (see FIG. 1) and the secondary air supply port 15 (see FIG. 1) by opening and closing the damper. The turbine exhaust gas is also supplied to the co-firing burner 5 from a desired number of tertiary air supply ports 18 (see FIG. 1) as necessary. When the gas turbine 31 is stopped, only external air is supplied to the co-firing burner 5 from the primary air supply port 14 (see FIG. 1) as combustion air.

With the above configuration, regardless of the stoppage of the gas turbine 31, the steam from the boiler 40 is supplied to drive the steam turbine 43, and the generator 33 is driven to obtain the generated power. Air conditioning such as heating and cooling can be stably performed.

Next, an experimental example will be described. Capacity
Using a boiler 40 of 40 ton / H, a gas turbine 31 with a capacity of 4000 kw is supplied to the co-firing burner 5 with an oxygen concentration of 13.0 to 15.0.
% Of turbine exhaust gas at a temperature of 450 to 600 ° C at a flow rate of 48000Nm
^When supplied at ³ -wt / H, the flow rate of digestive gas is 140
When 00Nm is ³ -wt / H, the supply amount of the city gas is 200 Nm ³ -
wt / H was sufficient, and the supply of city gas when the flow rate of digestive gas was zero was 2200 Nm ³ -wt / H. From this, it was clear that the turndown ratio could be as large as 1 to 11.

As the main fuel gas in the above embodiment,
As long as the calories are constant, city gas (13
Not limited to A), various gases such as liquefied natural gas (LPG) can be applied. In addition, the low calorie gas whose calories fluctuate is not limited to digestive gas, but also blast furnace gas (BFG) generated during blast furnace operation, coke oven gas (COG) generated during coke oven operation, and 3.36 to 42MJ, including by-product gas such as converter gas (LDG)
Gas whose calorie fluctuates as / m ³ can be applied.

[0048]

As is apparent from the above description, according to the mixed burning burner of the first aspect of the present invention, a burner gun for ejecting a main fuel gas having a constant calorie is provided, and a swirler is provided at the tip of the burner gun. And, since the burner nozzles that eject low calorie and calorie fluctuating gas are dispersed or provided around the swirler, it can have a larger turndown ratio than the conventional heavy oil, and from the burner nozzle, Even if the calorie of the gas to be jetted is reduced or the supply of gas to the burner nozzle is stopped, the burner gun can satisfactorily replenish the calorie deficiency, thereby ensuring a high output as a co-firing burner. More specifically, for example, in the case of the conventional example in which heavy oil is ejected from the burner gun, when the calorie of the gas ejected from the burner nozzle decreases to a predetermined value or less due to a small turn-down ratio, the supply of the heavy oil exceeds the value. There is no way to adjust it depending on the amount, and the output as a co-firing burner cannot be so high. On the other hand, in the co-firing burner according to the first aspect of the invention, the output as the co-firing burner can be increased by an amount corresponding to the large turndown ratio. Therefore, when a constant output is required, high output can be handled, and the versatility is excellent.

According to the mixed combustion burner of the second aspect of the present invention, the main fuel gas is supplied during the flame of low calorie and calorie-varying gas supplied from the burner nozzle and burned by the flame holding of the swirler. by methane CH ₃ which is a component of the gas, since reduction treatment the oxide gas NO _X in the flame, can reduce generation of nitrogen oxide gas NO _X by the nitrogen oxide gas NO _X is reduced to nitrogen gas.

According to the third aspect of the present invention, since the combustion air is supplied to the burner nozzle from both the side far from the burner gun and the burner gun, the gas having a low calorie and a variable calorie can be favorably burned. it can

According to the mixed combustion burner of the present invention, since the combustion exhaust gas discharged into the combustion chamber is returned and added to the primary air and supplied to the burner nozzle for combustion, the nitrogen oxide gas NO _X is reduced favorably. it can.

Further, according to the exhaust gas treatment apparatus of the invention according to claim 5, the mixed burner according to any one of claims 1, 2, 3, and 4 having a large turndown ratio is used. By using the combustion exhaust gas from gas turbines and gas engines as combustion air to burn low-calorie, calorie-varying gas, the gas can be satisfactorily burned without supplying new air. It can be effectively reduced nitrogen oxide gas NO _X.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of a co-firing burner according to a first embodiment of the present invention.

FIG. 2 is a right side view of FIG.

FIG. 3 is a left side view of FIG.

FIG. 4 is a front view of a main part showing a second embodiment of the co-firing burner according to the present invention.

FIG. 5 is a partially broken whole front view showing a third embodiment of the co-firing burner according to the present invention.

FIG. 6 is a view taken along line AA of FIG. 6;

FIG. 7 is an overall schematic configuration diagram showing a digestion gas combustion processing system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Combustion chamber 5, 25 ... Mixed combustion burner 6, 26 ... Burner gun 7 ... Primary swirler 8, 29 ... Burner nozzle 28 ... Swirler 31 ... Gas turbine R ... Air supply path R1 ... Primary air supply path R2 ... Secondary air supply path R3 … Exhaust gas recirculation channel

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F23R 3/36 F23R 3/36 (72) Inventor Yasuo Tanaka 4-1-1 Hiranocho, Chuo-ku, Osaka-shi, Osaka No. 2 Inside Osaka Gas Co., Ltd. (72) Yoshinobu Nagata 1-2-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Prefecture 1-2. Inside Osaka Gas Co., Ltd. (72) Makoto Hirano, 4-chome, Hirano-cho, Chuo-ku, Osaka, Osaka 1-2-2 Inside Osaka Gas Co., Ltd. (72) Inventor Yutaka Takamatsu 1-338 Nonakakita, Yodogawa-ku, Osaka City, Osaka Prefecture Inside Volcano Co., Ltd. (72) Inventor Minoru Soejima 1 Nonakakita, Yodogawa-ku, Osaka City, Osaka Prefecture 3rd-38 Volcano Co., Ltd. F term (reference) 3K065 TA01 TA15 TC08 TC10 TD05 TE07 TF02 TH19 TJ03 TJ06 TL02 TL03 3K091 AA01 AA20 BB01 BB26 CC06 CC07 CC23 EC04 EC13

Claims (5)

[Claims] 1. A burner gun for emitting a main fuel gas having a constant calorie, a swirler attached to a tip of the burner gun to generate a swirling flow for flame stabilization, and a dispersed or annularly provided around the swirler. A co-firing burner, comprising: a burner nozzle that emits a low-calorie, calorie-varying gas; and an air supply path that supplies combustion air to the burner nozzle and the burner gun. 2. The burner gun according to claim 1, wherein a tip of the burner gun projects beyond the swirler, and a main fuel gas from the burner gun is supplied into a flame burned by a burner nozzle to reduce nitric oxide gas. A mixed burner. 3. A primary air supply passage provided on the side of the burner nozzle and distant from the burner gun to supply primary air for combustion, and a periphery of the burner nozzle. And a secondary air supply passage provided on the burner gun side for supplying secondary air for combustion. 4. A flue gas recirculation flow path for sucking and recirculating flue gas exhausted into a combustion chamber is provided on a side of the burner nozzle around the burner nozzle far from the burner gun, and the combustion is performed in addition to the primary air. A co-firing burner configured to supply exhaust gas to the burner nozzle. 5. A combustion exhaust gas from a gas turbine and / or a gas engine is supplied as air for combustion according to any one of claims 1, 2, 3, and 4. Exhaust gas treatment equipment.