EP1910768A1

EP1910768A1 - Selective cleaning of heat exchanger devices in the boiler of a combustion plant

Info

Publication number: EP1910768A1
Application number: EP06818233A
Authority: EP
Inventors: Manfred Frach; Bernd Mussmann
Original assignee: Bergemann GmbH
Current assignee: Bergemann GmbH
Priority date: 2005-07-29
Filing date: 2006-07-18
Publication date: 2008-04-16
Anticipated expiration: 2026-07-18
Also published as: US7891323B2; DE102005035556A1; CN101233382A; WO2007028447A1; CN101233382B; US20080210178A1; EP1910768B1

Abstract

The invention relates to the boiler (1) of a combustion plant (2) comprising at least one heat exchanger device (3) which can be traversed by a medium (4) from an inlet (5) to an outlet (6) and is held in the interior (7) of the boiler (1) by means of at least one suspension device (8), wherein means for determining the temperature of the medium (4) are provided at least at the inlet (5) or at the outlet (6), and the at least one suspension device (8) has means for determining the weight of the at least one heat exchanger device (3). The invention also proposes a cleaning control device, a cleaning method and a method for operating a combustion plant. The invention permits a considerable reduction in the cleaning expenditure, so that maintenance costs can be kept low.

Description

Selective cleaning of heat exchangers in the boiler of an incinerator

The present invention relates to a boiler of a combustion plant comprising at least one heat exchange device, which flows through a medium from an inlet to an outlet and is held in the interior of the boiler by means of at least one hanger. Furthermore, a cleaning control device for a boiler of a combustion power plant with at least one heat exchange device and at least one cleaning device for removing combustion residues is described. The invention also relates to a cleaning method for selectively cleaning at least one heat exchange device in the boiler of an incinerator and to a method for operating an incinerator. The invention finds particular application in the field of steam generation, boiler plants heated with fossil fuels and / or additives, waste incineration plants, etc.

The residues from the combustion of coal and / or additional fuels lead to contamination of the heat exchange surfaces during operation of boilers of a combustion plant, which have adverse effects on the operation of the incinerator. The consequences are, for example, efficiency losses due to an increased exhaust gas temperature and / or a required, relatively intensive cleaning of the heat exchange surfaces. In addition, stoppages of the incinerator may be required to remove stubborn slag. It is also problematic that incineration residues may accumulate in a concentrated manner at a position of the incineration plant, whereby these so-called "beards" may detach from the walls and cause damage on impact at facilities of the incineration plant the Combustion residues are removed from the heat exchange surfaces at predetermined time intervals.

For cleaning such heat exchange surfaces, a large number of different cleaning concepts are already known. Thus, in addition to the mechanical cleaning (eg by means of so-called knocking devices or steel balls) and the cleaning by means of compressed air or sound, often also resorted to a cleaning of the heat exchange surfaces by means of steam or water. Heat has to be removed from the slag mixtures for cleaning before they solidify. Cold water as a cleaning medium is particularly suitable for this purpose. The destruction and detachment of the combustion residues is caused by the sudden evaporation of the impinging and penetrating water and the associated increase in volume and by the kinetic effect of the impinging cleaning jet. However, the thermal shock effect desired with the combustion residues can lead to additional stresses in the pipe material, which can cause damage if the cleaning process is used in an uncontrolled manner. Blast jet velocity, cooling time, blast jet geometry, amount of water and others determined the intensity of the thermal shock.

For cleaning by means of a blowing medium translationally movable and stationary swivel blower are known. Moving wind players, such as pushers, lunge blowers, long-thrust blowers, rotary-tube blowers, math players, are regularly driven into internal areas of the boiler only for cleaning purposes. Accordingly, they are moved in translationally, wherein the lance carrying the cleaning medium optionally rotates, so that the nozzles attached to the lance clean the environment around the lance. In the case of stationary swiveling blowers, for example, single nozzles, steam gun blowers or so-called automatic water lancet blowers (manufacturer: Clyde Bergemann GmbH) are installed. The cold water is supplied at the water lance blowers with a pressure of 12 to 15 bar. The effective length The blow jet is about 20 to 22 m and the blower per blower 200 to 400 m ² , so that such a cleaning device is particularly suitable for cleaning opposite wall portions of the boiler at a free interior. The fan produces a jet of water, the impingement diameter of which is advantageously less than 1 m, so that an area can be cleaned by means of targeted, meander-shaped blowing patterns.

The cleaning with water jets briefly influences the combustion process, changes the behavior of different combustion control loops and the amount of steam. The injected cold water also influences the flue gas temperature, the amount of flue gas and the amount of heat transferred. The cleaning of combustion chamber pipe walls with water jets also claimed the pipe material, as this is exposed by the thermal shock increased thermal stresses.

The object of the present invention is to at least partially solve the technical problems described with reference to the prior art. In particular, a device is to be specified with which a selective and effective cleaning of heat exchange devices inside a boiler of a combustion plant can be performed. Likewise, methods are to be specified, which ensure gentle cleaning at a consistently high efficiency of the incinerator.

These objects are achieved with a boiler of a combustion plant measures the features of claim 1, a cleaning control device for a boiler of an incinerator with the features of claim 8 and a cleaning method for selectively cleaning at least one

Heat exchange device according to the features of claim 9. Further advantageous embodiments are listed in the respective depending formulated patent entitlements, the features mentioned there individually in any, technologically more meaningful, can be combined with each other and lead to further embodiments of the invention.

The boiler of an incinerator proposed here comprises at least one heat exchange device, which can be flowed through by a medium from an inlet to an outlet and held in the interior of the boiler by means of at least one hanger. According to the invention, means for determining the temperature of the medium are provided at least at the inlet or at the outlet, and the at least one hanging device has means for determining the weight of the at least one heat exchange device.

The boiler referred to here is preferably a coal-fired, in particular lignite-fired, boiler of an incinerator. The invention described here is particularly advantageous for boilers having at least one vertically arranged interior, shaft or so-called "train" (in particular so-called "tower boiler" and / or "2-pass boiler"), in which a plurality The combustion exhaust gas flows through the heat exchange means against gravity, transferring heat from the hot exhaust gas to the heat exchange means.

The heat exchange device is preferably designed as a so-called tube bundle or as a coil. Such a heat exchange device accordingly comprises at least one, preferably multiply bent, tube, through which a medium, for example water or steam, flows, and with the aid of which the heat can be removed from the interior of the vessel. Such heat exchange devices span, for example, a cross section of the boiler of 20 mx 20 m and have a height of up to 3 m. For tower boilers for lignite or hard coal, for example, at least 5 or 7 such heat exchange devices can be arranged one above the other be. Such a heat exchange device has its own circuit, so that the medium, in particular water or steam, is introduced via an inlet of the heat exchange device into inner regions of the boiler and led out again via an outlet. As it flows through the heat exchange device, the medium absorbs heat energy.

As a measure of the heat exchange, the temperature of the medium can be used. Therefore, here means for determining the temperature of the medium are positioned at least at the inlet or at the outlet. Initially, it is irrelevant whether the temperature of the medium is determined directly or indirectly, for example based on the temperature of the line, etc. The positioning of the means is preferably such that a temperature characteristic of the entry of the medium is detected with a corresponding characteristic temperature of the medium near the outlet. With a desired good heat transfer from the exhaust gas via the heat exchanger device to the medium, a relatively high temperature is found near the outlet. Over time, if slag, ash or other incineration residue accumulates on the surface of the heat exchanger, the heat transfer from the exhaust gas to the medium is hindered, so that the temperature of the medium near the outlet decreases with time. The provision of such means for determining the temperature of the medium thus makes it possible to determine to what extent an entire heat exchange device still fulfills the desired function. This can already be a first statement for a pending cleaning of the heat exchange device can be obtained, which can only gain information that an entire heat exchange device is to be cleaned.

In view of the size of the heat exchange device, several cleaning devices are regularly used, which together would effect a large-scale cleaning. In order to obtain further information on the exact position of the deposited combustion residues, the combination with other means is now mentioned here, so that more exact statements about the position of the Combustion residues can be obtained. Here it is therefore proposed that the at least one hanger has means for determining the weight of the at least one heat exchange device. Due to the combustion processes inside the boiler or the positioning of internals inside the boiler, partially preferred flow paths of the exhaust gas through the boiler occur. This results in an uneven distribution of combustion residues on the heat exchange device. By providing means for determining the weight, statements about the weight distribution of the heat exchange device can be obtained, so that it becomes clear which zones or partial regions of a single heat exchange device are particularly dirty. Based on this knowledge, it is now possible to carry out selective cleaning precisely only of the heavily soiled parts of the heat exchange device.

This particular combination of means for monitoring localized deposits of combustion residues with respect to a heat exchange device has the further advantage that the means for determining the temperature of the medium and the means for determining the weight of the heat exchange means proposed here can be positioned outside the boiler, so that they are not exposed to the high thermal and dynamic stresses in the interior of the boiler. For more accurate information can be produced, a simplified data transmission possible and simple sensors and the like can be used. Also in terms of retrofitting and the repair of funds, there are significant benefits in terms of cost and installation.

In addition, it should be noted that the selectivity only reduced cleaning effort is operated, so that the risk of damage to the heat exchange facilities diminished and the thermal conditions in the interior of the boiler is only slightly affected. For example, previously it was necessary to completely clean a heat exchange device all use a soot blower associated with a heat exchanger for a period of four to five hours, so here the amount of cleaning medium or the time for cleaning can be significantly reduced.

According to a preferred embodiment, the means for determining the temperature of the medium comprise at least one evaluation unit, which determines a temperature difference of the medium with respect to the inlet and the outlet. In particular, in the event that it can not be ensured that the medium flows into the heat exchange device at a relatively constant temperature, it is advantageous to determine the inlet temperature and consequently the temperature difference between the inlet and outlet of the medium as a measure of the current heat transfer in terms Heat exchange device to use. A large temperature difference initiates that a good heat transfer is possible, so the heat exchange device is substantially free of combustion residues. In contrast, a small temperature difference shows that the medium has hardly absorbed any heat during the passage through the heat exchanger, which is very likely due to the build up of combustion residues on the heat exchanger.

It is further proposed that the at least one suspension device comprises a plurality of support elements, which is fastened in each case via at least one suspension point with the at least one heat exchange device. The support elements are preferably tubes, struts, chains or the like, which are positioned from a ceiling of the boiler hanging evenly over a cross section of the boiler. These support elements preferably have a plurality of suspension points for a single heat exchange device, so that, for example, such a tube coil or a tube bundle is fastened several times via a support element. Very particular preference is the embodiment of the hanger in the way that with a support element and a plurality of heat exchange devices are fixed in the interior of the boiler. According to a further embodiment of the boiler, the at least one hanger and the at least one heat exchange device are connected to each other via a plurality of suspension points, wherein the suspension points are arranged distributed evenly in a plane transverse to gravity and in the region of the at least one heat exchange device. Most preferably, the suspension points form corner points for portions of the heat exchange device, so that the heat exchange device is subdivided similarly to a grid. The subregions can have substantially the same surface area, but this is not absolutely necessary. The "even" distribution of suspension points has the advantage that the exact same information about the accumulation of combustion residues can be obtained over the cross section of the heat exchanger or via the boiler In particular, the suspension points with respect to which a weight determination is made are selected such that they are positioned approximately in the range of the range limit of the respective cleaning device Thus, for example, it can be detected and / or determined which of the cleaning devices adjacent to one another is to be used.

Particularly preferred is the embodiment in which the means for determining the weight comprise at least one strain gauge. Strain gauges are understood here to mean in particular flat measuring sensors or sensors, which can be characterized by an electrical resistance. If they experience a deformation, this results in a change in their electrical resistance. Such strain gauges (DMS) are used to detect changes in shape (strains / compressions) on the surface of components, such as the suspension elements of the hanger. Such Strain gauges often consist of a kind of measuring grid, which is either meandered from a thin resistance wire or etched from a thin film of resistance material. The measuring grid is regularly mounted on a thin plastic carrier and provided with electrical connections. The electrical resistances formed with the measuring grid are exposed in use mechanical loads that change the amount of resistance. If a strain gauge is stretched, its resistance increases regularly. The change in the resistance is usually detected by the integration in an electrical circuit (Wheatstone bridge) and used for the quantitative assessment of the stress-induced deformation. Such strain gauges are relatively inexpensive and simple, so that they can be integrated without great technical effort outside the boiler in the hanger. Thus, for example, a characteristic number of the support elements can also be retrofitted with such strain gauges.

Furthermore, it is now proposed that at least one cleaning device for removing combustion residues at the at least one heat exchange device is provided in the boiler that can assume different operating states with regard to the cleaning effect on partial regions of the at least one heat exchange device. The embodiment in which a plurality of (for example three, four or five) cleaning devices are provided is preferred. It is with regard to a heat exchange device, which is constructed with tubes, preferably to translationally movable sootblowers, which can be retracted into inner regions of the heat exchange device.

The cleaning effect of the cleaning device is influenced, for example, by the cleaning medium used, the blow jet produced (in terms of number, pressure, shape and orientation) and the method of movement of the cleaning device. In view of the fact that the device is intended to enable selective cleaning of the heat exchange device, preference is given to those cleaning devices which can purify the surface to be cleaned in a targeted manner and others Clean parts less or not at all. So it is possible, for example, that a targeted change in the pressure or the composition of the blowing medium (water / steam) is possible. Furthermore, special drives of the cleaning device can be provided, which enable targeted cleaning of the surface to be cleaned, for example by different speeds of advance of the lance into the heat exchange device, a variation of the rotation speed of the lance, the connection and disconnection of nozzles, etc Advantageously, the cleaning effect can be predetermined flexibly via a control unit.

The boiler can also be further developed by providing a control unit connected to the means for determining the temperature of the medium, the means for determining the weight of the at least one heat exchange device and at least one cleaning device for removing combustion residues. In this case, information is supplied to the control unit which first of all predetermines the choice of a cleaning appliance and, on the other hand, may influence its operation. For example, if a plurality of cleaning devices are provided in several levels of the boiler, the cleaning devices at the height of the heat exchange device to be cleaned can be selected on the basis of the information obtained with the means for determining the temperature of the medium. If now the information obtained with the means for determining the weight of the at least one heat exchange device that only a part of this heat exchange device is to be cleaned, the number of cleaning devices to be used can be further reduced and coordinated with regard to the cleaning effect on partial areas. In particular, such a control unit also comprises data processing devices and data processing programs.

According to a further aspect of the invention, a cleaning control device for a boiler of an incineration plant is provided with at least one heat exchanger. Substitute and at least one cleaning device for removing combustion residues proposed, comprising at least the following:

a plurality of weight sensors for determining the weight distribution of the at least one heat exchange device

- At least one control unit for activating at least one cleaning device, and

- means for data connection of temperature sensor, weight sensors, control unit.

This cleaning control device is preferably integrated in a boiler of the type described above.

With regard to the temperature sensors mentioned here, reference is made essentially to the above description of the means for determining a temperature of the medium, in particular with regard to their arrangement. The design of the temperature sensor itself is not decisive here. Preferably, the embodiment in which two temperature sensors are provided per heat exchange device, for. One at the inlet and one at the outlet of the medium.

Here, the weight sensors fulfill the function as already described above in connection with the means for determining the weight. In particular, the weight sensors comprise strain gauges. The arrangement of the weight sensors is chosen here so that statements about the weight distribution can be made.

The control unit for activating a cleaning device is preferably integrated in a data processing system. It controls or regulates the activation and / or the cleaning action of a cleaning device. For this purpose, the control unit may also be provided with a data memory in which, for example Reference limit values for the activation or operation of the cleaning devices are stored. Advantageously, the control unit comprises all means necessary to enable automatic operation of the selective cleaning of heat exchangers in a boiler.

The means for data connection may include cable, radio and similar connections, as far as their functionality is not impaired in view of the prevailing environmental conditions.

A further aspect of the invention relates to a cleaning method for selectively cleaning at least one heat exchange device which can be flowed through by a medium from an inlet to an outlet and held in the interior of a boiler of an incineration plant by means of at least one hanger, which comprises at least the following steps: a) Detecting at least one parameter from temperature or temperature difference of the medium during operation, b) detecting a weight distribution of the at least one heat exchange device, c) identifying a surface to be cleaned of the at least one heat exchange device, d) cleaning the identified surface.

This cleaning method is preferably realized in the boilers described according to the invention or with the above-described cleaning control device.

With step a), the temperature or temperature difference of the medium with respect to each heat exchange device during operation of the incinerator or the boiler is detected or determined and / or stored continuously or at predetermined time intervals. With regard to step b), it should be noted that the detection of a weight distribution is advantageously carried out jointly for a plurality of heat exchange devices. By means of the information from temperature / temperature difference and weight distribution, the surface to be cleaned is identified with respect to the heat exchange devices to be cleaned (step c)). The cleaning (only) of the identified area can be carried out separately with respect to a heat exchange device or simultaneously for a plurality of heat exchange devices.

According to a development of the cleaning method, the heat exchange device to be cleaned is determined by means of step a) and the area to be cleaned there is determined by means of step b). In a tower boiler can therefore be identified with step a) the heat exchange device, which only allows a small heat transfer to the medium, or the height / level with the appropriate cleaning equipment for their cleaning. A further local, selective determination of the area to be cleaned is now carried out by means of step b), in which areas with an increase in weight are detected. Since the throughflow behavior of the exhaust gas through the tower boiler is the same on a regular basis, the values determined by step b) apply in a similar manner to all heat exchange devices provided there.

Furthermore, it is also proposed that step d) is performed only when a predetermined value range of the surface to be cleaned is identified. This means in particular that, under certain circumstances, a predetermined number of partial areas or a sufficiently large total area with respect to one or more heat exchange devices may have to be present before a cleaning process is actually carried out. Thus, for example, it is possible that a single subarea is already cleaned if the temperature difference of the medium between the inlet and outlet falls below a critical value and / or a critical weight value is exceeded with respect to a subarea of the heat exchanger device. On the other hand, however, it is also possible for further limit values to be defined in addition to this critical limit value, in which case possibly contiguous subareas of a heat exchange device and / or several surfaces of different heat exchange units. cleaned at the same time. The criteria for such a targeted implementation of the cleaning process, for example, the time and cost of cleaning, in particular travels of the cleaning equipment and the amount of cleaning medium used are to be considered.

Finally, it is also proposed with respect to the cleaning method that it is advantageous if step d) comprises cleaning the identified area with an increased cleaning intensity compared with other partial areas of the at least one heat exchange device. In connection with the increased cleaning intensity, reference is made to the above-described cleaning effect of the cleaning devices. An increased cleaning intensity can be described, for example, with an increased amount of the cleaning medium per unit area, an increased bubble energy per unit area, and the like.

With regard to a method for operating an incinerator, wherein the incinerator has a plurality of heat exchange devices, each of which is flowed through by a medium from an inlet to an outlet and held in the interior of a boiler of the incinerator by means of a common hanger Furthermore, and a plurality of cleaning devices are provided for removing combustion residues at the heat exchange devices, it is very particularly advantageous that a cleaning process of the type described above according to the invention is carried out during the operation of the incinerator. This has the advantage that, on the one hand, the efficiency of the incineration plant is not influenced in such a significant way as was the case with known plants, which resulted in complete purification of the heat exchange devices. In addition, the cleaning processes themselves can be reduced to approximately one fifth of the cleaning time of known systems, whereby the amount of cleaning medium used can be reduced by, for example, more than 40%. The associated positive effects in terms of operating cost and life expectancy of the heat exchange facilities are obvious.

The present invention will be explained in more detail with reference to FIGS. The figures show schematic representations to illustrate the invention and the technical environment of the invention. The particularly preferred embodiment variants of the invention shown there do not restrict the application of the invention and can not regularly be used to illustrate size ratios. Show it:

1 shows a boiler of a combustion plant,

2 shows a heat exchange device as a schematic plan view,

3 shows a detail of a boiler with a cleaning control device,

4 shows an illustration of the interaction of a cleaning control device with sensors and cleaning device,

Fig. 5: a cleaning cycle with respect to a heat exchange device.

Fig. 1 shows a boiler 1 in the manner of a tower boiler, wherein in the firing space 22 shown below coal or lignite is burned, and the exhaust gas to the heat exchange devices arranged above 3 or flows therethrough, before finally via a flue gas line 23rd further (not shown here) facilities of the incinerator 2 is supplied. The boiler 1 has above the combustion chamber 22 still a portion of the interior space 7, which is substantially free of internals. This area of the interior 7 can preferably be cleaned by stationary blowers, which are pivotally positioned in a permanently hatch of the boiler wall. For example, by means of sensors in the opposite boiler wall can be detected when a cleaning is required, so that then the pivoting cleaning devices 14 can be activated. These clean the opposite wall of the boiler with freely definable blow patterns and speeds.

In the upper area of the boiler 1, a plurality of heat exchange devices 3 are now positioned, which are flowed through by a medium 4 from an inlet 5 to an outlet 6. The arranged in the interior 7 of the boiler 1 four heat exchange devices 3 are held by a hanger 8. In the illustrated embodiment, the hanging device 8 is formed with a plurality of support elements 10, which are each attached via a plurality of suspension points 11 with the heat exchange devices 3. Basically, it does not depend on the actual design of the hanging device 8, so that this is also indicated only schematically. It can be designed differently depending on the type of boiler, as well as with regard to the type, number and location of the heat exchanging devices, etc.

Each heat exchange device 3 is provided with means for determining the temperature of the medium 4 at the inlet 5 and at the outlet 6, namely with temperature sensors 19. The hanging device 8 is provided with means for determining the weight or the weight distribution in common for all heat exchanging devices 3, wherein these Strain gauges 13 for each support element 10 include. In the arrangement of the means for determining the weight or the weight distribution is important that they can generate a statement about the weight distribution over the cross section of the boiler 1 and the heat exchange device 3.

By means of the temperature sensors 19, the temperature of the medium 4 is detected during operation of the boiler 1. In addition, the weight distribution of the heat exchange devices 3 is determined via the strain gauges 13. From these characteristics, the area to be cleaned of the corresponding heat exchange device 3 is now identified, before finally this by means of here next the boiler 1 illustrated cleaning equipment 14 (preferably in the manner of a translationally movable Rußbläsers) to be cleaned.

Fig. 2 shows schematically a plan view of a heat exchange device 3, as it spans, for example, the cross section of a variant of a boiler 1. The heat exchanger 3 is fixed to the hanger 8 (not shown) via a plurality of suspension points 11 in a horizontal or horizontal plane 12, respectively. The suspension points 11 are here regularly or uniformly distributed in the plane 12, so that different partial areas 16 can be delimited. In the illustrated embodiment, the suspension points 11 are arranged in rows and columns perpendicular thereto. In addition to these lines or columns, individual diagrams are shown, which illustrate the time course of the weight of the heat exchange device.

On the right hand side of Fig. 2, there is shown, by way of example, the data obtained in evaluating the strain gages 13 attached to one or more support members 10 attached to the respective row (as illustrated in Fig. 1). The diagrams now illustrate a threshold 25 in terms of weight and a time 26 at which this threshold 25 is exceeded. As can be seen from the diagrams on the right, with regard to the two lower lines of suspension points 11, an exceedance of the limit value 25 has already been ascertained, this taking place at different points in time 26.

Similarly, the column-by-column evaluation of the weight distribution is illustrated. The diagrams shown below in FIG. 2 again show, by way of example, the change in weight over time. In the diagrams shown at the bottom left, the limit value 25 with respect to a critical weight was also exceeded at a different point in time 26. In the situation illustrated here by way of example, it can now be recognized with the aid of a suitable cleaning control device 18 (not shown) that there is an accumulation of combustion residues in the lower left area with respect to one (or all) heat exchange device (s) 3, so that the one to be tapped here - Nigende surface 21 is located. To clarify the question of which heat exchange device 3 is actually to be cleaned by the majority, the temperature of the medium can be used.

FIG. 3 illustrates a possible situation in a boiler 1, wherein in turn a plurality of heat exchanging devices 3 is provided. Due to the operation of the incinerator or the boiler 1, a one-sided accumulation of combustion residues 15 takes place. As a result of this one-sided attachment increased tensile forces are applied to the support members 10 in this area, which lead to a change in length of the support elements 10, which by means of weight sensors 20 (eg in the manner of a strain gauge) can be detected. Due to the greater load on the support element 10 shown on the left, different measured values are detected by means of the weight sensors 20 and passed on to a cleaning control device 18. In order to enable selective cleaning of the heat exchanger device 3, in addition with respect to each heat exchanger device 3, the temperature difference of the medium with respect to the inlet and the outlet is determined. For this purpose, temperature sensors 19 are positioned near the inlet and the outlet, wherein an evaluation unit 9 determines a temperature difference of the medium. The results of this evaluation unit 9 are likewise made available to the cleaning control device 18. Based on these measured values of the weight sensors 20 and the temperature sensors 19, an activation of cleaning devices (not shown) is now specifically carried out on the basis of the control unit 17. It should be explicitly pointed out that in particular the evaluation units 9 can be combined with each other and optionally also part of the cleaning control device 18 can be. Likewise, it is also possible that the data transfer starting from a Cleaning controller 18 is made to a remote control unit 17.

4 shows a schematic illustration of a further embodiment variant of a cleaning control device 18. The control device 18 is particularly suitable for use with a boiler of a combustion plant with at least one heat exchange device and at least one cleaning device for removing combustion residues. The cleaning control device 18 comprises a plurality of temperature sensors 19 for determining a temperature of the medium in the heat exchange devices (not shown), a plurality of weight sensors 20 for determining the weight distribution of the at least one heat exchange device, a control unit 17 for activating at least one cleaning device (not shown) and Data links 24 to the temperature sensors 19, weight sensors 20 and the control unit 17. Such a cleaning control device 18 may also be the subject of a data processing system, a data carrier and / or an operating method.

Fig. 5 will now also illustrate the cleaning process itself. Shown is a heat exchange device 3, which is formed with a plurality of tubes 29. For example, as already explained with reference to FIG. 2, this heat exchanging device 3 can be subdivided into a plurality of subregions 16, wherein surfaces 21 of the heat exchanging device 3 to be cleaned with the means for determining the temperature of the medium and the means for determining the weight distribution can be identified , The identification of the surface 21 to be cleaned has already been carried out in the illustrated situation so that the surface 21 to be cleaned, which is hatched, results.

For cleaning this heat exchange device 3, a plurality of cleaning devices 14 can be used, three cleaning devices 14 being shown here. These cleaning devices 14 are preferably a kind of sootblowers, the can be introduced with a feed direction 27 into inner regions of the heat exchange device 3, so that the blowing jet 30 can act in intermediate spaces between the tubes 29.

For the cleaning plan resulting here, a feed direction 27 from left to right is realized with the above-described cleaning device 14, wherein the cleaning device 14 is operated with a substantially constant rotation 28 of the lance 31, which is to be illustrated by the uniform course of the wavy line.

Although the cleaning device 14 shown below is moved in translation with the same feed direction 27, but with different speeds. In this cleaning device 14, the rotation 28 was maintained at the same speed, wherein in the portions of the heat exchange device 3, which need not be cleaned, an increased feed rate was realized, in contrast, in the area of the surface to be cleaned 21 with respect to the other Cleaning equipment 14 was slowed down. This allows an increased release of cleaning medium in this area.

Also shown below in FIG. 5 is a cleaning device 14, which operates in a manner similar to the cleaning device 14 shown above, but with the opposite direction of advance 27.

Furthermore, it is proposed that the cleaning devices 14 operate in the region of the surface 21 to be cleaned with increased pressure, so that here the cleaning medium (water) at about 20 bar in the environment or towards the heat exchange device 3 is discharged while outside of the cleaning surface 21 is operated only at about 10 bar. With the present invention, the risk of damage to parts of the boiler or the incinerator can be reduced. In addition, the cleaning cycles can be reduced from currently 4 to 5 hours per heat exchanger to less than 1 hour in some cases. Also, the use of the cleaning medium (for example, steam) can be reduced by up to 50%. The funds used to carry out the cleaning method are inexpensive and can be easily integrated outside the boiler without great thermal and / or dynamic load in existing internal combustion engines. This indicates a particularly effective combination of combustion residue detection means on heat exchange equipment.

LIST OF REFERENCE NUMBERS

1 boiler

2 incinerator

3 heat exchange device

4 medium

5 inlet

6 outlet

7 interior

8 hanging device

9 evaluation unit

10 support element

11 suspension point

12 level

13 strain gauges

14 cleaning device

15 combustion residue

16 subarea

17 control unit

18 cleaning control device

19 temperature sensor

20 weight sensor

21 area

22 firebox

23 flue gas line

24 data connection

25 limit

26 time

27 feed direction

28 rotation

29 pipe Blow jet lance

Claims

claims

A boiler (1) of an incinerator (2) comprising at least one heat exchange device (3) which can be flowed through by a medium (4) from an inlet (5) to an outlet (6) and in the interior (7) of the

Boiler (1) by means of at least one hanger (8) is held, wherein means for determining the temperature of the medium (4) at least at the inlet (5) or at the outlet (6) are provided, and the at least one hanger (8) means for Determining the weight of the at least one heat exchange device (3).

2. boiler (1) according to claim 1, wherein the means for determining the temperature of the medium (4) comprise at least one evaluation unit (9) having a temperature difference of the medium (4) with respect to the inlet (5) and the outlet (6 ).

3. boiler (1) according to claim 1 or 2, wherein the at least one hanger (8) comprises a plurality of support elements (10), each attached via at least one suspension point (11) with the at least one heat exchange device (3) is.

4. boiler (1) according to any one of the preceding claims, wherein the at least one hanger (8) and the at least one heat exchange means (3) via a plurality of suspension points (1 1) are interconnected, in which the suspension points (1 1 ) are distributed uniformly in a plane (12) transverse to the force of gravity and in the region of the at least one heat exchange device (3).

5. boiler (1) according to any one of the preceding claims, wherein the means for determining the weight comprise at least one strain gauge (13).

6. Boiler (1) according to one of the preceding claims, wherein at least one cleaning device (14) for removing combustion residues (15) on the at least one heat exchange device (3) is provided, with respect to the cleaning effect on portions (16) of the at least one Heat exchange device (3) can assume different operating conditions.

7. Boiler (1) according to one of the preceding claims, wherein a control unit (17) is provided, which with the means for determining the temperature of the medium (4), the means for determining the weight of the at least one heat exchange device (3 ) and with at least one cleaning device (14) for removing combustion residues (15) is connected.

8. cleaning control device (18) for a boiler (1) of a combustion system (2) with at least one heat exchange device (3) and at least one cleaning device (14) for removing combustion residues (15) comprising at least - at least one temperature sensor (19) for determining a Temperature of a medium (4) in the at least one heat exchange device (3), a plurality of weight sensors (20) for determining the weight distribution of the at least one heat exchange device (3), - at least one control unit (17) for activating at least one

Cleaning device (14), and

- Means for data connection of temperature sensor (19), weight sensors (20), control unit (17).

9. A cleaning method for the selective cleaning of at least one heat exchange device (3) which starts from a medium (4) starting from an inlet lass (5) can be flowed through to an outlet (6) and held in the interior (7) of a boiler (1) of a combustion plant (2) by means of at least one hanger (8), which comprises at least the following steps: a) detecting at least one parameter from temperature or temperature difference of the medium (4) during operation, b) detecting a weight distribution of the at least one heat exchange device (3), c) identifying a surface (21) to be cleaned of the at least one heat exchange device (3), d) cleaning the identified one Surface (21).

10. The cleaning method according to claim 9, wherein by means of step a) the heat exchange device to be cleaned (3) and by means of step b) the surface (21) to be cleaned there is determined.

11. A cleaning method according to claim 9 or 10, wherein step d) is performed only when a predetermined range of values of the surface to be cleaned (21) is identified.

A cleaning method according to any one of claims 9 to 11, wherein step d) comprises cleaning the identified area (21) with increased cleaning intensity over other portions (16) of the at least one heat exchange means (3).

13. A method for operating an incinerator (2), wherein the incinerator (2) has a plurality of heat exchange means (3), each of a medium (4) from an inlet (5) through to an outlet (6) flowed through and in the interior (7) of a boiler (1) of the incinerator (2) are held by means of a common hanger (8), and further a plurality of cleaning devices (14) for removing combustion residues (15) at the heat exchanger means (3) are provided, in which a cleaning method according to any one of claims 9 to 12 during the operation of the incinerator (2) is performed.