Method and Device for Monitoring the Combustion Process in a Power Station on the Basis of an Actual Concentration Distribution of a Material

Abstract

Methods and a device for monitoring the combustion process in a power station are provided. An actual concentration distribution of a material and/or an actual temperature distribution are measured in the combustion chamber. Conclusions are drawn regarding the type of combustion material on the basis of the measured actual concentration distribution or temperature distribution. A concentration distribution or temperature distribution of a material that has been determined using a sample fuel is compared with the measured actual concentration distribution or temperature distribution.

Description

FIELD OF INVENTION

The invention relates to a method for monitoring the combustion in a combustion chamber in a power station, with measurement of an actual concentration distribution of a substance or of an actual temperature distribution in the combustion chamber. Furthermore, the invention relates to a device for monitoring the combustion in a combustion chamber in a power station, using a device for measuring an actual concentration distribution of a substance or an actual temperature distribution in the combustion chamber.

BACKGROUND OF INVENTION

For power stations, the fundamental objective is to monitor the combustion which is taking place in a combustion chamber in the power station, for example a boiler with a base area of 10 meters by 10 meters, over as wide an area as possible, to enable the variables required for optimizing the combustion process to be derived therefrom.

Thus, absorption spectroscopy is a known method. As an alternative measurement technology, acoustic pyrometry is also known. Using absorption spectroscopy or acoustic pyrometry, it is only possible to measure mean values along a line in the boiler or combustion chamber.

For the purpose of calculating the temperature and concentration distributions in a plane in a combustion chamber from mean values measured at various places in a power station's combustion chamber, a known method is the CAT measurement technique, Computer Aided Tomography.

SUMMARY OF INVENTION

An object of the invention is to enable more extensive monitoring of the combustion in a power station, in order thereby to supply the basis for optimizing the combustion process.

The object is achieved by methods and a device as claimed in the independent claims. Advantageous developments are described in the dependent claims.

In a first form of embodiment, a method in accordance with the invention for monitoring the combustion in a combustion chamber in a power station includes the steps: measure an actual concentration distribution of a substance in the combustion chamber, and draw conclusions about the nature of the fuel on the basis of the measured actual concentration distribution. In a second advantageous alternative or additional form of embodiment, a method in accordance with the invention for monitoring the combustion in a combustion chamber in a power station includes the steps: measure an actual temperature distribution in the combustion chamber and draw conclusions about the nature of the fuel on the basis of the measured actual temperature distribution.

Correspondingly, a first form of embodiment of a device in accordance with the invention for monitoring the combustion in a combustion chamber in a power station includes equipment for measuring an actual concentration distribution of a substance in the combustion chamber and equipment for drawing conclusions about the nature of the fuel on the basis of the measured actual concentration distribution. In a second advantageous, alternative or additional form of embodiment, equipment in accordance with the invention for monitoring the combustion in a combustion chamber in a power station includes equipment for measuring an actual temperature distribution in the combustion chamber and equipment for drawing conclusions about the nature of the fuel on the basis of the measured actual temperature distribution.

In other words, the basic idea underlying the invention is that for fuels of a known nature, in particular known types of coal, it is possible to determine characteristic distributions, in particular two-dimensional distributions, for the concentration of at least one substance in the waste gas and/or for the temperature in the combustion chamber. By reference to such characteristic distributions, it is possible to recognize the nature of the fuel and in particular of the type of coal. After this, the recognized nature or type can then be advantageously taken into account in regulating the combustion and in particular in the automatic switchover of control parameters, such as for example the excess air, for the purpose of reducing the emission of pollutant substances and for reducing the fuel consumption.

In the above definition of the invention, the term “substance” refers generally to any type of combustion product, in particular in the form of gas as a component of the waste gas. Furthermore, the term fuel is to be understood as material of any nature which comes to be burned in power stations. For coal-fired power stations, which are particularly relevant in the present case, these are coals of different natures or different types of coal.

In drawing conclusions about the nature of the fuel, a comparison is made respectively between a concentration distribution for the substance determined from a fuel sample, or a temperature distribution determined for it, and the measured actual concentration distribution or temperature distribution, as applicable.

With one advantageous development of the solution in accordance with the invention, when drawing conclusions about the nature of the fuel a comparison is made with at least one stored characteristic concentration sample for the substance or a stored characteristic temperature sample, as appropriate.

With another advantageous development of the solution in accordance with the invention, the drawing of conclusions about the nature of the fuel takes place at the same time as the measurement. That is, it is not imperative to use a sequential procedure in the measurement of concentrations and the temperature and the subsequent drawing of conclusions about the nature of the fuel, but these steps can also take place simultaneously, so that the conclusions drawn in accordance with the invention can be produced particularly quickly and particularly informatively. In summary, it is thus simply possible in a way which is cost-effective, simple and at the same time is a reliable process, to achieve a recognition of the quantitative composition of a fuel which, although only approximated, is on the other hand very up-to-date.

The advantageous developments cited for the inventive method will preferably also be realized in the farm of appropriately adapted equipment in the inventive devices.

BRIEF DESCRIPTION OF THE DRAWINGS

An exemplary embodiment of the inventive solution is explained in more detail below by reference to the attached schematic drawings. These show:

FIG. 1 an exemplary embodiment of the inventive device, and

FIG. 2 an exemplary embodiment of the inventive method.

DETAILED DESCRIPTION OF INVENTION

FIG. 1 shows a combustion chamber 10 in a coal-fired power station, which is not shown further here, wherein a coal-fired furnace burns when the coal-fired power station is in operation. The combustion chamber 10 then has in it the coal fuel with its associated combustion gases, several flames 11 and waste gases.

Provided in the combustion chamber 10 are two measurement planes 12 and 14, which are horizontal and parallel to one another, on the peripheral edges of each of which are several measuring instruments 16, spaced apart from each other. In each case, two of the measuring instruments 16 permit measurement along a line in the associated measurement plane, 12 or 14 as applicable, wherein the concentration of the substances O₂ (oxygen) and CO (carbon monoxide) can be measured with the help of the measuring instruments 16 and an associated analysis device 18.

Furthermore, using the measuring instruments 16 and the analysis device 18 it is possible to determine the temperature distribution in the associated measurement plane, 12 or 14 as applicable. Here, the measurement is based on a combination of measurement technology and CAT calculation.

The analysis device 18 is coupled operationally via a data bus 20 to an optimization device 22, an operating device 24, and management equipment or control and instrumentation equipment 26. Via the operating device 24, the actual concentration distributions and temperature distributions in the planes 12 and 14, measured by the analysis device 18, can be used to enable the optimization device 22 to draw conclusions from them about the nature of the fuel currently burning in the combustion chamber 10, in the present case the type of coal which is there.

The nature of the fuel is determined in order to optimize the flames 11 burning in the combustion chamber 10, in particular in respect of a low emission of NO_x (oxides of Nitrogen).

For the purpose of determining the nature of the fuel, the optimization device 22 uses stored characteristic samples of the concentrations of the substances cited in the waste gas and of the temperature, which have been determined using reference fuels and stored in the optimization device 22. The actual measured distributions of the concentration and the temperature are compared with these samples and matches are recognized by a comparison of this type.

The associated method is illustrated in FIG. 2. It includes the step 28 of measuring in the plane 12 the concentration distribution, e.g. of the substances O₂ and CO, and the temperature distribution. In step 30 the concentration distribution, for example of the substances O₂ and CO, in the plane 14 and the temperature distribution there, are measured at the same time. In step 32 the concentration distribution and the temperature distribution in the planes 12 and 14 are, as explained above, analyzed in such a way that conclusions can be drawn about the nature of the fuel in the combustion chamber 10.

On the basis of this conclusion, optimization of the combustion is then effected in a step 34, for example by a change in the air layering and/or a section by section change in the excess air.

Claims

1.-7. (canceled)

8. A method of monitoring combustion in a combustion chamber in a power station, comprising: providing a combustion chamber and a fuel;burning the fuel in the combustion chamber;measuring an actual concentration distribution of a substance in the combustion chamber; anddrawing conclusions about the fuel based upon the measured actual concentration distribution,wherein a comparison is made between a concentration distribution for the substance, determined from known fuels as sample fuels, and the measured actual concentration distribution.

9. The method as claimed in claim 8, wherein the comparison is made with at least one stored sample characteristic concentration for the substance.

10. A method for monitoring combustion in a combustion chamber in a power station, comprising: providing a combustion chamber and a fuel;burning the fuel in the combustion chamber;measuring an actual temperature distribution in the combustion chamber; anddrawing conclusions about the fuel based upon the measured actual temperature distribution,wherein a comparison is made between a temperature distribution determined with a sample fuel and the measured actual temperature distribution.

11. The method as claimed in claim 10, wherein the comparison is made with at least one stored characteristic temperature distribution.

12. The method as claimed in claim 10, wherein the drawing of conclusions about the fuel is effected at a same time as the measuring.

13. The method as claimed in claim 8, wherein the drawing of conclusions about the fuel is effected at a same time as the measuring.

14. A device for monitoring combustion in a combustion chamber in a power station, comprising: a measuring device for measuring an actual concentration distribution of a substance in the combustion chamber; andan evaluation device for drawing conclusions about a fuel on the basis of the measured actual concentration distribution.

15. The device as claimed in claim 14, further comprising: a measuring device for measuring an actual temperature distribution in the combustion chamber,wherein the conclusions are based upon the measured actual temperature distribution and the measured actual concentration distribution.

16. The device according to claim 14, wherein the analysis device is coupled via a data bus to the evaluation device, an operating device, and instrumentation equipment.

17. The device according to claim 16, wherein the evaluation device includes an optimization device.

18. The device according to claim 17, wherein, via the operating device, the actual concentration distributions and the actual temperature distributions, are used such that the optimization device draws conclusions about a quantitative composition of the fuel currently burning in a combustion chamber.

19. The device according to claim 18, wherein the quantitative composition of the fuel is determined in order to optimize flames burning in the combustion chamber, in particular in respect of a low emission of NOx (oxides of nitrogen).