DE202007003565U1 - Control circuit for controlling a combustion process - Google Patents

Abstract

loop for controlling a combustion process in a plant (1), in particular a power plant, a waste incineration plant or a cement plant, with a track (3), which has a furnace (13) for converting good (G) while supplying air (L) by means of the Combustion process with formation of at least one flame body (F) comprising at least one measuring device (5) for detecting Measurement data of the route (3), at least one adjusting device (9) for controlling at least the supply of good (G) and / or air (L) and a computer (11) to which the measuring device (5) and the adjusting device (9) are connected and which the measurement data of the measuring device (5) evaluates the state described by the measured data Systems evaluated on the basis of optimization goals, to achieve the Optimization goals suitable actions of the adjusting device (9) selects and the control device (9) controls, characterized in that at the furnace (13) a scanner (17) is arranged, which as an additional Measuring device (5) to the computer (11) is connected and which the temperature distribution on the ...

Description

The The invention relates to a control circuit for controlling a combustion process with the features of the preamble of claim 1.

at a known control circuit of this kind are essentially in the computer Measured data on mass flows, temperature distributions and processed flame images. It makes sense first as possible a lot of information about to get the state of the system to get better results of the scheme to achieve. The regulation may vary depending on the plant, that a reduction to a smaller amount of data is possible.

Of the The present invention is based on the object, a control loop to improve the type mentioned. This task is done by a control circuit with the features of claim 1 solved. Further advantageous embodiments are the subject of the dependent claims.

Thereby, that on the oven, a scanner is arranged, which as an additional Measuring device is connected to the computer and which the temperature distribution on the outside of the furnace and supplies the measured data to the computer stand Previously disregarded data available in the prior art, which used to describe and evaluate the condition of the system can be. The regulation will be better, especially more accurate and faster.

By doing on the route an acoustic sensor is provided, which as an additional Measuring device is connected to the computer and its measurement data supplies to the computer, are previously disregarded in the art Data available, which for describing and evaluating the state of the system can be used. The Regulation will be better, especially more accurate and faster. The acoustic sensor detects the noises generated by the moving good, which information about the consistency of the material and thus the properties contained in the combustion process.

The Invention can be applied to various stationary thermodynamic systems, in particular coal, oil or gas-fired power plants, waste incineration plants and cement plants.

In the following the invention with reference to an embodiment shown in the drawing is explained in more detail. The only figure shows
a schematic representation of the embodiment.

In the embodiments is a plant 1 provided, which is to be regulated by means of a control loop. The attachment 1 includes a (rule) route 3 , at least one, preferably a plurality of different measuring devices 5 , which measured data of the route 3 capture, at least one, preferably a plurality of different adjusting devices 9 , which on the track 3 can act and a calculator 11 to which the measuring device (s) 5 and adjusting device (s) 9 are connected, whereby the control loop is formed.

The way 3 Material to be converted, referred to as Good G for short, eg fuels such as coal, oil, gas, other primary fuels, refuse or other secondary fuels, as well as in the case of cement plants lime, and primary air (or oxygen) and secondary air (or oxygen) , briefly referred to as air L, supplied, this supply by the computer 11 controllable adjusting devices 9 is controlled. As the centerpiece of the track 3 is a stove 13 provided in which a combustion process takes place. The measuring devices 5 capture so much measurement data of the track 3 as possible, for example, images of the flame body F produced by the combustion process, possibly emissions of the walls of the furnace 13 , other thermal images, temperatures, pressures, mass flows of goods G, air L, in case of cement works of cooling cement Z and exhaust gases, pollutant concentrations in exhaust gases and in case of cement plants as quality measure for cement Z the concentration of free lime (FCAO ).

The measurement data of the measuring devices 5 be in the calculator 11 evaluated. After predefined setpoint values and further optimization targets, for example a low consumption of primary fuel or of residues poor exhaust gases, in particular low pollutant concentrations, the actual state of the system, which is described in a time-dependent manner by the measurement data used as state variables, is calculated by the computer 11 rated. By means of a computer 11 stored process model, which is constantly being improved, are taking into account possible actions of the adjusting devices 9 Predictions about future states of the system. Based on these predictions, the calculator chooses 11 appropriate actions that should bring the state of the system closer to the optimization goals, and then by the adjusting devices 9 be executed. The control loop is closed.

As a rule, the material G is moved to the flame body F, possibly also preprocessed, for example to contain particles with a larger surface area. In the movement of the goods G, especially in the case of particles, noises arise, which in connection with the consis the good of G For example, the particle size of harder G influences the noise. The consistency of the product G in turn has an influence on the combustion process and the particle size of the products. For example, the size of the surface of particles defines their combustibility.

According to the invention is an acoustic sensor 15 as another measuring device 5 - in addition to the commonly used measuring devices 5 - Provided, for example, a conventional carbon microphone or a piezoelectric element. The acoustic sensor 15 is designed to detect sound, phonons or other carrier-based vibrations. The acoustic sensor 15 is spatially arranged so that it can detect the noise generated by the moving good G. The acoustic sensor 15 is to the calculator 11 connected and provides this his measurement data. The additional information about the consistency of the goods G is taken into account by the calculator 11 the measurement data of the acoustic sensor 15 in its assessment of the state and its predictions. The regulation of the plant 1 can then be done more precisely and faster.

Preferably, the calculator corrects 11 the measurement data of the acoustic sensor 15 by subtracting the background noise. Such background noises are delivered by the devices intended for moving the goods G already without good G. The background noise is determined in advance by a corresponding measurement at idle. The measurement is repeated from time to time to detect the increase in background noise caused by wear.

Optionally, from the measurement data of the acoustic sensor 15 in the case of correspondingly long series of measurements and occasional linkage with other measurements, for example X-ray or optical measurements, in particular diffraction measurements, the particle sizes are determined directly.

In the embodiment, the system 1 a cement plant. The oven 13 is a rotary kiln, which is oriented obliquely and rotates, so that the fed from above Good G relative to the furnace 13 moved in the circumferential direction and slowly slips down. The acoustic sensor 15 is on the outside of the oven 13 arranged below it, preferably in a region in which the good G has not reached the flame body F, ie slightly above the flame body F. The acoustic sensor 15 is close to the wall of the oven 13 arranged so that it can detect the sounds of - in particular rolling - good G. The evaluation including the preferred background noise correction is done as previously described.

At the stove 13 is also a scanner 17 arranged, which the temperature distribution on the lateral surface of the furnace 13 captured while holding the oven 13 lengthwise and thereby the rotation of the furnace 13 considered. The scanner 17 serves, by the stove 13 To find places whose wall thickness is too low due to wear. The computer 11 can now use the scanner connected to it 17 as another measuring device 5 handle and the measurement data of the scanner 17 Also, evaluate that from the temperature distribution over the oven 13 the approximate position of the flame body F determined. Not only can the position of the flame body F be included in the general description and evaluation of the state of the system, it can also be used in case of tendencies to displace the flame body F, the acoustic sensor 15 to move.

1

investment

3

route

5

measuring device

9

locking device

11

computer

13

oven

15

acoustic sensor

17

scanner

F

flame body

G

Well

L

air

Z

cement

Claims (10)

Control circuit for controlling a combustion process in a plant ( 1 ), in particular a power plant, a waste incineration plant or a cement plant, with a route ( 3 ), which has a furnace ( 13 ) for converting good (G) with supply of air (L) by means of the combustion process to form at least one flame body (F), at least one measuring device ( 5 ) for acquiring measurement data of the route ( 3 ), at least one adjusting device ( 9 ) for controlling at least the supply of good (G) and / or air (L) and a computer ( 11 ) to which the measuring device ( 5 ) and the adjusting device ( 9 ) and which the measurement data of the measuring device ( 5 ) evaluates the state of the system described by the measured data on the basis of optimization targets, and to achieve the optimization objectives suitable actions of the adjusting device ( 9 ) and the actuator ( 9 ), characterized in that the furnace ( 13 ) a scanner ( 17 ) arranged as an additional measuring device ( 5 ) to the computer ( 11 ) and which the temperature distribution on the outside of the furnace ( 13 ) and the measurement data to the Computer ( 11 ). Control circuit according to claim 1, characterized in that the goods (G) on the route ( 3 ) by means of at least one device ( 13 . 19 ) to the flame body (F) in the furnace ( 13 ) is moved. Control circuit according to claim 2, characterized in that at the track ( 3 ) an acoustic sensor ( 15 ) is provided which detects the noise generated by the moving material (G) and the measurement data to the computer ( 11 ). Control circuit according to claim 3, characterized in that the computer ( 11 ) in the evaluation of the measurement data of the acoustic sensor ( 15 ) the measurement data around the background noise of the device (G) for moving the device ( 13 . 19 ) corrected. Control circuit according to claim 4, characterized in that the background noise when idling the device ( 13 . 19 ) and the measurement is repeated to detect the background noise due to wear. Control circuit according to one of claims 3 to 5, characterized in that from the measured data of the acoustic sensor ( 15 ), if appropriate, the particle size of the product (G) is determined by comparison with other measurements. Control circuit according to one of Claims 3 to 6, characterized in that the acoustic sensor ( 15 ) is designed as a piezoelectric element. Control circuit according to one of Claims 3 to 7, characterized in that the acoustic sensor ( 15 ) directly or close to the outer wall of the device (G) for moving the device ( 13 . 19 ) or within it. Control circuit according to one of Claims 3 to 8, characterized in that the system ( 1 ) is a cement plant and that designed as a rotary kiln, rotating furnace ( 13 ) moves the good (G). Control circuit according to one of Claims 3 to 9, characterized in that the acoustic sensor ( 15 ) below the furnace ( 13 ) is disposed in an area where the material (G) is close to the flame body (F).