GAS BURNER DEVICE AND METHOD FOR OPERATING A GAS BURNER DEVICE

Description

[0001] The invention relates to a gas burner device according to the preamble of patent claim 1 and a method for operating a gas burner device according to the preamble of patent claim 8.

[0002] A gas burner device of the type mentioned above is known from document US 2016 / 0146455 A1. This device consists of a conveying device for conveying a gaseous fuel to a burner, a recirculation device for returning an exhaust gas quantity produced during combustion of the fuel to the burner, and a control device for controlling the recirculation device. In procedural terms, in this solution, a gaseous fuel is conveyed to a burner by a conveying device, and an exhaust gas quantity produced during combustion of the fuel is returned to the burner by a recirculation device. In this solution, a valve (see reference numerals 128 and 228 therein) is provided on the recirculation device for adjusting the said exhaust gas quantity.

[0003] The invention is based on the object of improving a gas burner device of the type mentioned above and a method for operating such a gas burner device. In particular, a gas burner device that can be used more universally with regard to the gaseous fuel used, and a more universal method for operating the same, are to be created.

[0004] This object is achieved objectively with a gas burner device of the type mentioned above by the features listed in the characterizing part of patent claim 1. In terms of method, this object is achieved with a method for operating such a gas burner device by the features listed in the characterizing part of patent claim 8.

[0005] According to the invention, a sensor device is provided for determining a composition of the fuel, wherein the control device is designed to control the recirculation device as a function of the composition of the fuel detected by the sensor device.

[0006] According to the method, the invention provides that a composition of the fuel is determined by a sensor device and the recirculation device is controlled as a function of the composition of the fuel detected by the sensor device.

[0007] The term "controlled", used in this context for the sake of simplicity, encompasses the two terms "control" and "regulate" commonly used in control engineering.

[0008] In other words, the gas burner device according to the invention and the method according to the invention for operating such a gas burner device are characterized in that the amount of exhaust gas returned to the burner is determined based on the composition of the fuel. This has the unexpected result that a single burner can burn both natural gas and liquefied petroleum gas, for example, and even hydrogen, without any further component changes or parameter adjustments.

[0009] The objective or procedural requirement that "a sensor device is provided for determining a composition of the fuel" or that "a composition of the fuel is determined using a sensor device" means, quite generally, that the sensor device is suitable for drawing conclusions about the composition of the fuel, either directly or indirectly. The sensor device can thus be designed, for example, as a gas chromatograph, but also as a temperature sensor for detecting the combustion surface temperature, as will be discussed in more detail below. It is also conceivable, for example, that a UV-light-measuring sensor device is used to detect the so-called OH and / or CH bands, which arise as an intermediate product during combustion and from which the composition of the fuel can be deduced.In short: The sensor device can be designed in very different ways; ultimately, its purpose is to determine the composition of the fuel used in order to determine, on this basis, the amount of exhaust gas actually required for clean combustion.

[0010] Other advantageous developments of the gas burner device according to the invention or of the method according to the invention emerge from the dependent patent claims.

[0011] For the sake of completeness, the following documents are also mentioned.

[0012] A burner device with a conveying device and recirculation device is also known from patent DE 39 38 090 C1. In this solution, which, however, does not have a sensor device for determining the fuel composition, the two impellers are mounted on a common drive shaft and therefore cannot be operated independently of each other.

[0013] From the document FR 2 711 224 A1 a burner device is also known in which the conveying device and the recirculation device are firmly connected to each other.

[0014] A boiler with two flue gas paths is known from patent DE 693 12 226 T2.

[0015] From the document WO 1995 / 023315 A1 a burner for the combustion of hydrogen is known, in which, however, only a local recirculation in the area of ​​the individual flame tongues (flame recirculation) is provided.

[0016] From the document US 2004 / 025805 A1 a gas burner device is known which, like the solution according to the document US 2016 / 0146455 A1 mentioned at the beginning, has a conveying device and a recirculation device which is suitable for being controlled.

[0017] From the document DE 198 38 361 A1 it is known to determine the fuel gas composition in a gas combustion device by means of a sensor in order to take into account changes in the fuel gas composition when controlling the fuel gas quantity.

[0018] The gas burner device according to the invention and the method according to the invention for operating such a gas burner device are explained in more detail below with reference to the drawing of a preferred embodiment.

[0019] It shows schematically Figure 1 shows the gas burner device according to the invention with a sensor device arranged in front of the fuel-air mixing device, seen in the flow direction of the fuel.

[0020] The gas burner device shown in the figure consists, in a known manner, first of all of a conveying device 1 for conveying a gaseous fuel to a burner 2, a recirculation device 3 for returning an amount of exhaust gas produced during combustion of the fuel to the burner 2, and a control device 6 for controlling the recirculation device 3. The conveying device 1 preferably comprises a fan.

[0021] In procedural terms, a method for operating a gas burner device is provided in which a gaseous fuel is conveyed to a burner 2 by a conveying device 1 and an exhaust gas quantity produced during combustion of the fuel is returned to the burner 2 by a recirculation device 3.

[0022] What is essential for the gas burner device according to the invention is that a sensor device 4 is provided for determining a composition of the fuel and that the recirculation device 3 is designed to be controlled as a function of the composition of the fuel detected by the sensor device 4.

[0023] Again expressed in terms of the method, the invention provides that a composition of the fuel is determined by a sensor device 4 and the recirculation device 3 is controlled as a function of the composition of the fuel detected by the sensor device 4.

[0024] Looking at it in more detail, it is particularly preferably provided that the sensor device 4 is designed optionally as a gas chromatograph, as a gas thermal conductivity sensor, as an ionization sensor, as a UV sensor, as an oxygen sensor and / or as a temperature sensor (in particular a flame temperature sensor).

[0025] The gas chromatograph and the gas thermal conductivity sensor are arranged upstream of (i.e., in the area before combustion) the fuel flow direction, while the ionization sensor, the UV sensor, the oxygen sensor, and / or the temperature sensor are arranged downstream of or on burner 2 (i.e., in the combustion area). The single figure schematically shows the option of a gas chromatograph or a gas thermal conductivity sensor on the fuel supply line. The other options are not shown separately, as they are readily conceivable.

[0026] With regard to the UV sensor mentioned above, it is particularly preferred that it is designed to detect OH bands in the wavelength range from 300 nm to 320 nm, preferably 308 nm, and CH bands in the wavelength range from 410 nm to 450 nm, preferably 430 nm (see also https: / / www.uni-due.de / ivg / rf / forschung / chemilumineszenz.php).

[0027] As explained at the beginning, each sensor device 4 is suitable for determining the composition of the fuel used.

[0028] It is particularly preferred that hydrogen and / or natural gas are / is used as gaseous fuel.

[0029] It is furthermore particularly preferred that when pure hydrogen is used as fuel, a larger quantity of exhaust gas is returned to the burner 2 than when pure natural gas is used as fuel.

[0030] Furthermore, it is preferably provided that when using a mixture of hydrogen and natural gas as fuel, a smaller amount of exhaust gas is returned to the burner 2 than when using pure hydrogen and a larger amount of exhaust gas is returned than when using pure natural gas.

[0031] Furthermore, it is preferably provided that the recirculation device 3 comprises a recirculation valve 3.1, which is preferably and optionally arranged on the connecting line 3.3 (to be explained later) and / or connected to the control device 6. Or, in procedural terms: a recirculation valve 3.1 belonging to the recirculation device 3 controls the amount of exhaust gas returned to the burner 2. The aforementioned control device 6 is designed to be connected in terms of data technology, as shown in the single figure by a dotted line, optionally to the conveying device 1, the sensor device 4 and / or (as just explained) to the recirculation device 3 or the (preferably electrically actuated) recirculation valve 3.1. The conveying device 1 and the recirculation device 3 are preferably each controlled individually by the control device 6 depending on the composition of the fuel.

[0032] Furthermore, it is particularly preferably provided that a fuel-air mixing device 5 is arranged upstream of the burner 2, preferably, as shown, upstream of the conveying device 1, as viewed in the direction of fuel flow. In other words: a fuel-air mixing device 5 provided for mixing the gaseous fuel with air is controlled by the control device 6 depending on the composition of the gaseous fuel. It is further preferably provided that, in addition to a fuel supply connection 5.1 and an air supply connection 5.2, this device has an exhaust gas supply connection 5.3 connected to the recirculation device 3.

[0033] Furthermore, it is preferably provided that the burner 2 (for example, as schematically shown, a cylindrical burner) is arranged in a combustion chamber 2.1 with an exhaust gas discharge connection 2.2, and the recirculation device 3 has an exhaust gas connection 3.2 connected to the exhaust gas discharge connection 2.2. Finally, the exhaust gas connection 3.2 of the recirculation device 3 is preferably connected to the exhaust gas supply connection 5.3 of the fuel-air mixing device 5 via a connecting line 3.3. List of reference symbols

[0034] 1Feeding device 2Burner 2.1Combustion chamber 2.2Flue gas discharge connection 3Recirculation device 3.1Recirculation valve 3.2Flue gas connection 3.3Connecting line 4Sensor device 5Fuel-air mixing device 5.1Fuel supply connection 5.2Air supply connection 5.3Flue gas supply connection 6Control device

Claims

1. A gas-burner device comprising a conveying apparatus (1) for conveying a gaseous fuel to a burner (2), a recirculation apparatus (3) for returning to the burner (2) a quantity of exhaust gas produced during a combustion of the fuel, and a control apparatus (6) for controlling the recirculation apparatus (3), characterized in that a sensor apparatus (4) is provided for ascertaining a composition of the fuel and the control apparatus (6) is configured to control the recirculation apparatus (3) as a function of the composition of the fuel detected by the sensor apparatus (4).

2. The gas-burner device according to Claim 1, characterized in that the sensor apparatus (4) is selectively configured as a gas chromatograph, as a gas thermal conductivity sensor, as an ionization sensor, as a UV sensor, as an oxygen sensor and / or as a temperature sensor.

3. The gas-burner device according to Claim 1 or 2, characterized in that the recirculation apparatus (3) comprises a recirculation valve (3.1).

4. The gas-burner device according to one of Claims 1 to 3, characterized in that, when viewed in the direction of flow of the fuel, a fuel-air mixing apparatus (5) is arranged upstream of the burner (2).

5. The gas-burner device according to Claim 4, characterized in that the fuel-air mixing apparatus (5) has, in addition to a fuel supply connection (5.1) and an air supply connection (5.2), an exhaust gas supply connection (5.3) which is connected to the recirculation apparatus (3).

6. The gas-burner device according to one of Claims 1 to 5, characterized in that the burner (2) is arranged in a combustion chamber (2.1) with an exhaust gas discharge connection (2.2) and the recirculation apparatus (3) has an exhaust gas connection (3.2) which is connected to the exhaust gas discharge connection (2.2).

7. The gas-burner device according to Claims 5 and 6, characterized in that the exhaust gas connection (3.2) of the recirculation apparatus (3) is configured so as to be connected to the exhaust gas supply connection (5.3) of the fuel-air mixing apparatus (5) via a connecting line (3.3).

8. A method for operating a gas-burner device in which a gaseous fuel is conveyed by a conveying apparatus (1) to a burner (2) and a quantity of exhaust gas produced during a combustion of the fuel is returned to the burner (2) by a recirculation apparatus (3), characterized in that a composition of the fuel is ascertained by a sensor apparatus (4) and the recirculation apparatus (3) is controlled as a function of the composition of the fuel detected by the sensor apparatus (4).

9. The method according to Claim 8, characterized in that the conveying apparatus (1) and the recirculation apparatus (3) in each case are controlled individually as a function of the composition of the fuel.

10. The method according to Claim 8 or 9, characterized in that selectively hydrogen and / or natural gas are or is used as the gaseous fuel.