EP4056899A1 - Rotary grate with a fuel-independent cleaning device for a biomasse heating system and method for cleaning the grate - Google Patents

Abstract

Rotary grate (25) for a biomass heating system (1), having at least one rotary grate element (252, 253, 254) with a perforation of a plurality of slot-shaped openings (256); at least one bearing axis (81) by means of which the rotary grate element (252, 253, 254) is rotatably mounted; at least one cleaning device (125) attached to one of the rotary grate elements (252, 253, 254), the cleaning device (125) having a mass element (127x) that is movable relative to the rotary grate element (252, 253, 254) and lancing elements attached to the mass element (127x). (129) for the openings (256); wherein the cleaning device (125) is set up in such a way that when the rotary grate element (252, 253, 254) rotates, an acceleration movement of the mass element (127x) is initiated, so that the cleaning device (125) has a knocking effect on the rotary grate element (252, 253, 254 ) and exerts a piercing effect on the openings (256) in order to clean the rotary grate element (252, 253, 254) with its openings (256).

Description

TECHNICAL AREA

The invention relates to an improved rotary grate with a fuel-independent cleaning device for a biomass heating system.

In particular, the invention relates to a three-part rotary grate with improved cleaning for a fuel-flexible biomass heating system.

STATE OF THE ART

Biomass heating systems in a power range from 20 to 500 kW are known. Biomass can be considered a cheap, domestic, crisis-proof and environmentally friendly fuel. There are, for example, wood chips or pellets as combustible biomass or solid fuel.

The pellets usually consist of wood shavings, sawdust, biomass or other material that has been compacted into small discs or cylinders approximately 3 to 15 mm in diameter and 5 to 30 mm long. Wood chips (also known as wood chips, woodchips or woodchips) are wood that has been crushed with cutting tools.

Biomass heating systems for fuel in the form of pellets and wood chips essentially have a boiler with a combustion chamber (the combustion chamber) and a heat exchange device connected to it. Due to stricter legal regulations in many countries, some biomass heating systems also have a Fine dust filter on. Other various accessories are regularly available, such as control devices, probes, safety thermostats, pressure switches, exhaust gas or flue gas recirculation and a separate fuel tank.

A device for supplying fuel, a device for supplying air and an ignition device for the fuel are regularly provided in the combustion chamber. The means for supplying the air, in turn, normally comprises a high-efficiency, low-pressure fan in order to favorably influence the thermodynamic factors of combustion in the combustion chamber. A device for supplying fuel can be provided, for example, with a lateral insert (so-called transverse insert firing). The fuel is pushed into the combustion chamber from the side via a screw or a piston.

A firing grate is also usually provided in the combustion chamber, on which the fuel is essentially supplied and burned continuously. This grate stores the fuel for combustion and has openings that allow the passage of part of the combustion air as primary air to the fuel. Next, the grate can be rigid or movable. Movable grates are usually used for simple disposal of the combustion residues produced during combustion, such as ash and slag. However, these combustion residues can stick or cake on the grate and have to be cleaned off manually on a regular basis, which is disadvantageous. The ash and slag can also block the openings in the grate for air supply with the ash or slag, which adversely affects the combustion efficiency. Practice shows that the combustion residues can stick or cake, especially in the openings of the grate, which makes cleaning the grate even more difficult.

When the primary air flows through the grate, the grate is also cooled, which protects the material. Should the openings become clogged, this cooling effect will also be impaired.

In addition, insufficient air supply can lead to increased slag formation on the grate. In particular furnaces that are to be charged with different fuels, with which the present disclosure is particularly concerned, have the inherent problem that the different fuels have different ash melting points, water contents and different combustion behavior. It is therefore problematic to provide a heating system that is equally well suited for different fuels and whose grates can be cleaned in a correspondingly improved manner.

The combustion chamber can also be regularly divided into a primary combustion zone (direct combustion of the fuel on the grate) and a secondary combustion zone (post-combustion of the flue gas). The drying, pyrolytic decomposition and gasification of the fuel takes place in the combustion chamber. Secondary air can also be introduced in order to completely burn the resulting combustible gases.

After drying, the combustion of the pellets or wood chips essentially has two phases. In the first phase, the fuel is at least partially pyrolytically decomposed and converted into gas by high temperatures and air, which can be blown into the combustion chamber solids a. In this respect, the fuel outgasses and the resulting gas is also burned.

Pyrolysis is the thermal decomposition of a solid substance in the absence of oxygen. Pyrolysis can be divided into primary and secondary pyrolysis. The products of primary pyrolysis are pyrolysis coke and pyrolysis gases, the pyrolysis gases being divided into room temperature condensable and non-condensable gases. The primary pyrolysis takes place at roughly 250-450°C and the secondary pyrolysis at around 450-600°C. The secondary pyrolysis that subsequently occurs is based on the further reaction of the pyrolysis products that were primarily formed. The drying and pyrolysis take place at least largely without the use of air, because volatile CH compounds escape from the particle and therefore no air can reach the particle surface. Gasification can be seen as part of oxidation; the solid, liquid and gaseous products formed during the pyrolytic decomposition are reacted by further exposure to heat. This is done by adding a gasification agent such as air, oxygen or steam. The lambda value during gasification is greater than zero and less than one. Gasification takes place at around 300 to 850°C. Above approximately 850°C, complete oxidation takes place with excess air (lambda greater than 1). The end products of the reaction are essentially carbon dioxide, water vapor and ash. In all phases, the boundaries are not rigid, but fluid. The combustion process can be advantageously regulated by means of a lambda probe provided at the exhaust gas outlet of the boiler.

Generally speaking, the conversion of the pellets into gas increases the combustion efficiency because gaseous fuel is better mixed with the combustion air, and less emission of pollutants, less unburned particles and ash are produced.

Combustion of biomass produces airborne combustion products, the main components of which are carbon, hydrogen and oxygen. These can be divided into emissions from complete oxidation, from incomplete oxidation and substances from trace elements or impurities. The emissions from complete oxidation are essentially carbon dioxide (CO ₂ ) and water vapor (H ₂ O). The formation of carbon dioxide from the carbon in the biomass is the goal of combustion, since the energy released can be used in this way. The release of carbon dioxide (CO ₂ ) is largely proportional to the carbon content of the fuel burned; thus the carbon dioxide is also dependent on the useful energy to be provided. A reduction can essentially only be achieved by improving the efficiency. In any case, combustion residues such as ash and slag are also produced, which can adhere firmly to the grate.

Especially in biomass heating systems, which are intended to be suitable for different types of biofuel, the varying quality and consistency of the fuel makes it difficult to maintain a consistently high efficiency of the biomass heating system, especially since the ash and slag formation on the grate varies greatly dimensions can be done. There is a considerable need for optimization in this regard.

In addition, the biological fuel can be contaminated. These impurities can increase the formation of ash and slag and/or cause blockages in the openings of the grate.

Another disadvantage of conventional biomass pellet heating systems can be that pellets falling into the combustion chamber can roll or slide out of the grate and end up in an area of the combustion chamber where the temperature is lower or lower where the air supply is poor, or they can even fall into the bottom chamber of the boiler. Pellets that do not remain on the grid or grate burn incompletely, causing poor efficiency, excessive ash and a certain amount of unburned pollutant particles.

Biomass heating systems for pellets or wood chips have the following additional disadvantages and problems.

One problem is that incomplete combustion due to non-uniform distribution of fuel on the grid or grate and non-optimal mixing of air and fuel causes the accumulation and fall of unburned ash through the air inlet openings leading directly to the combustion grate , favored into the air ducts.

This is particularly annoying and causes frequent interruptions to perform maintenance such as cleaning. For all these reasons, a large excess of air is normally maintained in the combustion chamber, but this reduces the Flame temperature and combustion efficiency decrease, resulting in high NOx emissions. Such excess air is undesirable.

The above problems have been addressed in the prior art (post-published). EP 3 789 676 B1 treated with a cleaning device for a rotating grate with a beating action. A drop hammer configuration ensures that a mass element strikes a stop of the respective element when the elements of the rotary grate are rotated.

However, this prior art solution has been shown to have two disadvantages. On the one hand, the drop hammer configuration under the rotary grate principle requires quite a lot of space and is therefore too large for boilers with a lower output (and dimensioning), and on the other hand, the cleaning effect of the rotary grate still needs improvement.

Based on the problems mentioned above, it can be an object of the present invention to provide a grate for a biomass heating system, which is preferably provided in hybrid technologies, which allows an optimized operation of the biomass heating system.

For example, simple ash removal or cleaning of the grate should be made possible, and easy maintenance of the grate of the biomass heating system should be made possible.

In addition, there should be high system availability.

According to the invention and in addition, the following consideration could play a role:
The hybrid technology should enable the use of both pellets and wood chips with a water content of between 8 and 35 percent by weight.

The task(s) mentioned above or the potential individual problems can also relate to other aspects of the overall system, for example the combustion chamber or the air flow through the grate.

This object(s) is/are solved by the subject matter of the independent claims. Further aspects and advantageous developments are the subject matter of the dependent claims.

The advantages of this configuration and also the following aspects result from the following description of the associated exemplary embodiments.

Rotary grate for a biomass heating system, having at least one rotary grate element with a perforation made up of a plurality of slot-shaped openings; at least one bearing axis, by means of which the rotary grate element is rotatably mounted; at least one cleaning device attached to one of the rotary grate elements, the cleaning device having a mass element that is movable relative to the rotary grate element and piercing elements for the openings attached to the mass element; wherein the cleaning device is set up such that when the rotary grate element rotates, an acceleration movement of the mass element is initiated, so that the cleaning device exerts a knocking effect on the rotary grate element and a piercing effect on the openings in order to clean the rotary grate element with its openings.

Rotary grate for a biomass heating system according to the preceding aspect, wherein the cleaning device is set up such that
when the rotating grate element rotates to initiate the acceleration movement, the mass element is raised to a fall start position, from which the mass element falls linearly under the influence of gravitational acceleration by means of a linear guide in order to generate the knocking effect on the rotating grate element and at the same time the piercing effect for the openings.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein a fall height for the falling of the mass element and a mass of the mass element are set up such that when falling, ash deposits on and in the openings, which have arisen through sintering, are removed by the piercing effect be able.

Rotating grate for a biomass heating system according to one of the preceding aspects, wherein the linear guide is designed as a linear slide guide with two suspensions and two complementary guide openings.

Rotating grate for a biomass heating system according to one of the preceding aspects, wherein the piercing elements are designed in the form of a comb with a plurality of projections.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein the piercing elements have a length such that they can completely penetrate the openings, and the piercing elements are designed with projections in such a way that the projections taper continuously in the direction of their distal ends; and the lancing elements are arranged in such a way that they are respectively provided complementary to the openings.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein the piercing elements are plate-shaped, and the piercing elements have a fastening part for fastening to the mass element, and the piercing elements have a plurality of projections tapering in the length direction of the piercing element, and the piercing elements Central part between the fastening part and the projections.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein a length of the central part is dimensioned such that it can completely penetrate the rotary grate element.

Rotary grate for a biomass heating system according to one of the preceding aspects, the mass element having slot-shaped recesses in which the piercing elements for fastening the piercing elements to the mass element are accommodated.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein the mass element to which the piercing elements are attached is set up in such a way that a piercing element is provided for each opening of the rotary grate element.

Rotating grate for a biomass heating system according to any of the preceding aspects, wherein the cleaning device comprises:
a suspension attached to the rotating grate element and slide bearings in the mass elements which together form a linear carriage guide which enables linear movement of the mass element towards and away from the rotating grate element.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein at least three cleaning devices are provided for a rotary grate element, wherein one cleaning device is provided on a bearing axis of the rotary grate element, and the other cleaning devices are provided adjacent to each other.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein the mass element has plain bearings as the guide openings for receiving the suspension.
the mass element has two outer plates between which a plurality of inner plates are sandwiched, the inner plates having recesses which extend to the plain bearing.

A rotary grate for a biomass heating system according to any of the preceding aspects, wherein the cleaning means is mounted on the underside of the rotary grate member opposite a combustion surface of the rotary grate member.

Rotary grate for a biomass heating system according to one of the preceding aspects, wherein the rotary grate has a first rotary grate element, a second rotary grate element and a third rotary grate element, which are each arranged to be rotatable by at least 90 degrees about the respective bearing axis.

• zumindest ein Drehrostelement mit einer Perforation aus einer Mehrzahl von schlitzförmigen Öffnungen; zumindest eine Lagerachse , mittels der das Drehrostelement drehbar gelagert ist; zumindest eine an einem der Drehrostelemente angebrachte Reinigungseinrichtung, wobei die Reinigungseinrichtung ein relativ zum Drehrostelement linear bewegliches Masseelement mit einer Mehrzahl von Stechelementen aufweist;
• wobei das Verfahren die folgenden Schritte aufweist:

Method for cleaning a rotary grate of a biomass heating system, the rotary grate having the following:

• at least one rotary grate element with a perforation made up of a plurality of slot-shaped openings; at least one bearing axis, by means of which the rotary grate element is rotatably mounted; at least one cleaning device attached to one of the rotary grate elements, wherein the cleaning device has a mass element that is linearly movable relative to the rotary grate element and has a plurality of piercing elements;
• the method comprising the following steps:

rotating the rotary grate element in a first direction and moving the mass element of the cleaning device with it;

initiating an accelerating movement of the mass element;

Hitting the mass element with a knocking effect on a stop surface of either the rotating grate element or the cleaning device for cleaning the rotating grate element and with a piercing effect in the openings by means of the piercing elements.

Method for cleaning a rotary grate of a biomass heating system, according to the preceding aspect, wherein the mass element is raised when the rotary grate element rotates to initiate the acceleration movement to a fall start position, from which the mass element falls linearly under the influence of gravitational acceleration in order to reduce the knocking effect on the to produce a rotary grate element.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, which further has the following: at least one rotary grate element; at least one bearing axle, by means of which the rotary grate element is rotatably mounted; at least one cleaning device attached to one of the rotary grate elements, the cleaning device having a mass element that is movable relative to the rotary grate element; wherein the cleaning device is set up in such a way that when the rotary grate element rotates, an acceleration movement of the mass element is initiated, so that the cleaning device exerts a knocking effect on the rotary grate element in order to clean the rotary grate element.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the cleaning device is set up in such a way that the mass element is raised when the rotary grate element rotates to initiate the acceleration movement to a fall start position, from which the mass element is under the influence of gravitational acceleration to generate the knocking effect on the rotating grate element.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the cleaning device is set up such that the mass element of the cleaning device strikes a stop surface of the rotary grate element when it accelerates or falls.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, with: the cleaning device such is set up such that the mass element of the cleaning device deflects a striking arm during its acceleration or falling movement, so that it strikes a stop surface.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the cleaning device is set up in such a way that when the rotary grate element is rotated in a first direction and when the rotary grate element is rotated in a second direction, which is opposite to the first direction , each hitting a stop surface.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, wherein: the cleaning device is attached to the underside of the rotary grate element, which is opposite a combustion surface of the rotary grate element.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, wherein: the cleaning device has the following: a suspension attached to the rotary grate element with a joint; a beater arm having a first end and a second end, the mass member being provided at one of the ends of the beater arm; wherein the beating arm is connected to the suspension via the joint so that it can be pivoted about an axis of rotation of the joint.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the bearing axis of the rotary grate element is provided at least approximately parallel to the axis of rotation of the joint of the beater arm; and/or the bearing axis is arranged at least approximately horizontally.

According to a further development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the impact arm can be pivoted by a predefined angle between the fall start position and a fall end position is arranged; and/or the cleaning device is attached exclusively to the rotary grate element and is connected to it.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the cleaning device is set up with the mass element in such a way that the mass element has a flat striking surface which is aligned at least approximately parallel to the striking surface when struck.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: at least one stop surface is provided on the underside of the rotary grate element and/or on the bearing axis and/or on the cleaning device.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, wherein: the rotary grate elements form a combustion surface for the fuel; wherein the rotary grate elements have openings for the air for combustion, the openings being elongated in the form of a slit, a longitudinal axis of the openings being provided at an angle of 30 to 60 degrees to a fuel insertion direction.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the rotary grate has a first rotary grate element, a second rotary grate element and a third rotary grate element, which are each arranged to be rotatable by at least 90 degrees about the respective bearing axis.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, wherein: the rotary grate also has a rotary grate mechanism that is configured in such a way that it can rotate the third rotary grate element independently of the first rotary grate element and the second rotary grate element, and that these the first rotary grate element and the second Rotating grate element can rotate together and independently of the third rotating grate element.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, wherein: the rotary grate has a perforation; and wherein the perforation consists of a plurality of slit-shaped openings arranged in plan view of the rotary grate such that: a first number of the slit-shaped openings are arranged at a first angle and non-parallel to a direction of insertion of the fuel onto the rotary grate.

According to a development of one of the above aspects, a rotary grate is provided for a biomass heating system, with a second number of slot-shaped openings being arranged on the rotary grate at a second angle and not parallel to an insertion direction of the fuel.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, wherein: the first angle is greater than 30 degrees and less than 60 degrees; and the second angle is greater than 30 degrees and less than 60 degrees.

According to a development of one of the above aspects, a rotary grate for a biomass heating system is provided, wherein: a combustion surface of the rotary grate configures a substantially oval or elliptical combustion surface; and the insertion direction of the fuel is equal to a longer central axis of the oval combustion surface of the rotary grate.

According to a development of one of the above aspects, a method for cleaning a rotary grate of a biomass heating system is provided, the rotary grate having the following: at least one rotary grate element; at least one bearing axle, by means of which the rotary grate element is rotatably mounted; at least one cleaning device attached to one of the rotary grate elements, the cleaning device having a mass element that is movable relative to the rotary grate element; the method comprising the following steps:

rotating the rotary grate element in a first direction and moving the mass element of the cleaning device with it; initiating an accelerating movement of the mass element; Hitting the mass element with a knocking effect on a stop surface of either the rotary grate element or the cleaning device for cleaning the rotary grate element.

According to a development of one of the above aspects, a method for cleaning a rotary grate of a biomass heating system is provided, wherein the mass element is raised when the rotary grate element rotates to initiate the acceleration movement to a fall start position, from which the mass element falls under the influence of gravitational acceleration in order to counteract the knocking effect to generate on the rotary grate element.

According to a development of one of the above aspects, a method for cleaning a rotary grate of a biomass heating system is provided, with rotation of the rotary grate element in a first direction and rotation of the rotary grate element in a second direction, which is opposite to the first direction, impacting on a stop surface he follows.

The individual effects and advantages of these aspects result from the following description of the figures and the associated drawings.

In the present case, "horizontal" can denote a level orientation of an axis or a cross section, assuming that the boiler is also set up horizontally, with which, for example, the ground level can be the reference. Alternatively, "horizontal" as used herein means "parallel" to the base plane of the vessel, as commonly defined. As a further alternative, in particular if there is no reference plane, "horizontal" can be understood merely as at least approximately perpendicular to the direction of action of the gravitational force of the earth or gravitational acceleration.

Although all the above individual features and details of an aspect of the invention and the developments of this aspect are described in connection with the biomass heating system, these individual features and details are also disclosed as such independently of the biomass heating system.

The biomass heating system with the grate according to the invention and the grate according to the invention with the cleaning device / the cleaning devices is / are below in embodiments and individual aspects based on the

Fig. 1

zeigt eine dreidimensionale Überblicksansicht einer Biomasse-Heizanlage gemäß einer Ausführungsform der Erfindung;

Fig. 2

zeigt eine Querschnittsansicht durch die Biomasse-Heizanlage der Fig. 1, welche entlang einer Schnittlinie SL1 vorgenommen wurde und welche aus der Seitenansicht S betrachtet dargestellt ist;

Fig. 3

zeigt ebenso eine Querschnittsansicht durch die Biomasse-Heizanlage der Fig. 1 mit einer Darstellung des Strömungsverlaufs, wobei die Querschnittsansicht entlang einer Schnittlinie SL1 vorgenommen wurde und aus der Seitenansicht S betrachtet dargestellt ist;

Fig. 4

zeigt eine Teilansicht der Fig. 2, die eine Brennkammergeometrie des Kessels der Fig. 2 und Fig. 3 darstellt;

Fig. 5

zeigt eine Schnittansicht durch den Kessel bzw. die Brennkammer des Kessels entlang der Vertikalschnittlinie A2 der Fig. 4;

Fig. 6

zeigt eine dreidimensionale Schnittansicht auf die Primärverbrennungszone der Brennkammer mit dem Drehrost der Fig. 4;

Fig. 7

zeigt entsprechend zur Fig. 6 eine Explosionsdarstellung der Brennkammersteine;

Fig. 8

zeigt eine Aufsicht auf den Drehrost mit Drehrostelementen von oben aus Sicht der Schnittlinie A1 der Fig. 2;

Fig. 9

zeigt den Drehrost der Fig. 2 in geschlossener Position, wobei alle Drehrostelemente horizontal ausgerichtet bzw. geschlossen sind;

Fig. 10

zeigt den Drehrost der Fig. 9 in dem Zustand einer Teilabreinigung des Drehrosts im Gluterhaltungsbetrieb;

Fig. 11

zeigt den Drehrost der Fig. 9 im Zustand der Universalabreinigung, welche bevorzugt während eines Anlagenstillstands durchgeführt wird;

Figuren 12a bis 12d

zeigen eine Prinzipdarstellung eines Drehrosts mit einer beispielhaften Reinigungseinrichtung, welche sich mittels einer Drehung bewegt;

Figuren 13a und 13b

zeigen eine Prinzipdarstellung des erfindungsgemäßen Drehrosts mit einer Reinigungseinrichtung, welche sich linear bewegt;

Figuren 14a bis 14c

zeigen Ansichten auf einen erfindungsgemäßen Drehrost mit Reinigungseinrichtungen in einem ersten Zustand;

Figuren 15a bis 15b

zeigen Ansichten von Teilen der Reinigungseinrichtungen der Fig. 14a bis 14c;

Fig. 16

zeigt eine vertikale Querschnittsansicht auf den Rost der Fig. 14a in einem zweiten Zustand;

Fig. 17

zeigt eine vertikale Querschnittsansicht auf den Rost der Fig. 14a in einem dritten Zustand;

Fig. 18

zeigt eine vertikale Querschnittsansicht auf den Rost der Fig. 14a in einem vierten Zustand;

Fig. 19

zeigt eine vertikale Querschnittsansicht auf den Rost der Fig. 14a in einem fünften Zustand;

Fig. 20

zeigt eine vertikale Querschnittsansicht auf den Rost der Fig. 14a in einem sechsten Zustand;

Fig. 21

zeigt eine vertikale Querschnittsansicht auf den Rost der Fig. 14a in einem siebten Zustand;

Fig. 22

veranschaulicht die Probleme eines anderen Drehrosts mit einer Reinigungseinrichtung.

Figures explained in more detail:

1

shows a three-dimensional overview of a biomass heating system according to an embodiment of the invention;

2

shows a cross-sectional view through the biomass heating system 1 , which was taken along a section line SL1 and which is shown viewed from the side view S;

3

also shows a cross-sectional view through the biomass heating system of FIG 1 with an illustration of the flow path, wherein the cross-sectional view was taken along a section line SL1 and is shown viewed from the side S;

4

shows a partial view of the 2 , which has a combustion chamber geometry of the boiler 2 and 3 represents;

figure 5

shows a sectional view through the boiler or the combustion chamber of the boiler along the vertical section line A2 of FIG 4 ;

6

shows a three-dimensional sectional view of the primary combustion zone of the combustion chamber with the rotary grate 4 ;

7

shows according to 6 an exploded view of the combustion chamber bricks;

8

shows a top view of the rotary grate with rotary grate elements seen from the section line A1 of FIG 2 ;

9

shows the rotary grate of 2 in the closed position, with all rotary grate elements aligned horizontally or closed;

10

shows the rotary grate of 9 in the state of a partial cleaning of the rotary grate in ember maintenance mode;

11

shows the rotary grate of 9 in the state of universal cleaning, which is preferably carried out during a plant standstill;

Figures 12a to 12d

show a basic representation of a rotary grate with an exemplary cleaning device, which moves by means of a rotation;

Figures 13a and 13b

show a schematic representation of the rotary grate according to the invention with a cleaning device which moves linearly;

Figures 14a to 14c

show views of a rotary grate according to the invention with cleaning devices in a first state;

Figures 15a to 15b

show views of parts of the cleaning devices of FIG Figures 14a to 14c ;

16

shows a vertical cross-sectional view of the grate 14a in a second state;

17

shows a vertical cross-sectional view of the grate 14a in a third state;

18

shows a vertical cross-sectional view of the grate 14a in a fourth state;

19

shows a vertical cross-sectional view of the grate 14a in a fifth state;

20

shows a vertical cross-sectional view of the grate 14a in a sixth state;

21

shows a vertical cross-sectional view of the grate 14a in a seventh state;

22

illustrates the problems of another rotating grate with a cleaning device.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Various purely exemplary embodiments of the present disclosure are disclosed below with reference to the accompanying drawings. However, embodiments and terms used therein are not intended to limit the present disclosure to particular embodiments, and it should be construed to include various modifications, equivalents, and/or alternatives according to the embodiments of the present disclosure.

If more general terms are used in the description for features or elements shown in the figures, it is intended that not only the specific feature or element is disclosed in the figures for the person skilled in the art, but also the more general technical teaching.

With respect to the description of the figures, the same reference numbers can be used in the individual figures to refer to similar or technically corresponding elements. Furthermore, for the sake of clarity, more elements or features can be shown with reference symbols in individual detailed or sectional views than in the overview views. It can be assumed that these elements or features are also disclosed accordingly in the overview presentations, even if they are not explicitly listed there.

It is to be understood that a singular form of a noun corresponding to an object may include one or more of the things, unless the context in question clearly indicates otherwise.

In the present disclosure, an expression such as “A or B”, “at least one of A and/or B”, or “one or more of A and/or B” can include all possible combinations of features listed together. Terms such as "first," "second," "primary," or "secondary" as used herein may represent different elements regardless of their order and/or importance, and are not limiting of corresponding elements. When an element (e.g., a first element) is described as being "operably" or "communicatively" coupled or connected to another element (e.g., a second element), the element may be directly connected to the other element or to the other element connected via another element (e.g. a third element).

For example, a phrase "configured for" (or "configured for") as used in the present disclosure may be replaced with "suitable for,""suitablefor,""adaptedfor,""madefor,""capableof," or "designed for." depending on what is technically possible. Alternatively, in a particular situation, a phrase "device configured to" or "set up to" may mean that the device can operate in conjunction with another device or component, or perform a corresponding function.

All dimensions specified in "mm" are to be understood as a size range of +- 1 mm around the specified value, unless another tolerance or other ranges or range limits are explicitly stated.

It should be noted that the present individual aspects, for example the cleaning device, are disclosed here separately from or separate from the biomass heating system as individual parts or individual devices. It is therefore clear to the person skilled in the art that individual aspects or parts of the system are also disclosed here on their own. In the present case, the individual aspects or parts of the system are disclosed in particular in the sub-chapters marked by brackets. It is envisaged that these individual aspects can also be claimed separately.

Furthermore, for the sake of clarity, not all features and elements are individually identified in the figures, especially if they are repeated. Rather, the elements and features are each designated as examples. Analogous or identical elements are then to be understood as such.

(biomass heating system)

First, the biomass heating system 1 of the present disclosure is to be described in general in order to shed more light on the "environment" of the present rotary grate 25 with its cleaning device 125 .

1 shows a three-dimensional overview of an exemplary biomass heating system 1, which can contain the rotary grate 25 according to the invention with a cleaning device 125.

The arrow V in the figures indicates the front view of the plant 1, and the arrow S in the figures indicates the side view of the plant 1.

The biomass heating system 1 has a boiler 11 which is mounted on a base 12 of the boiler. The boiler 11 has a boiler housing 13, for example made of sheet steel.

In the front part of the boiler 11 there is a combustion device 2 (not shown), which can be reached via a first maintenance opening with a closure 21 . A rotary mechanism mount 22 for a rotary grate 25 (not shown) supports a rotary mechanism 23 with which drive forces can be transmitted to bearing axles 81 of the rotary grate 25 .

In the central part of the boiler 11 there is a heat exchanger 3 (not shown), which can be reached from above via a second maintenance opening with a closure 31 .

In the rear of the vessel 11 is an optional filter assembly 4 (not shown) having an electrode 44 (not shown) suspended by an insulating electrode support 43 and powered by an electrode supply line 42 . The exhaust gas from the biomass heating system 1 is discharged via an exhaust gas outlet 41 which is arranged downstream (fluidically) of the filter device 4 in terms of flow. A fan can be provided here.

A recirculation device 5 is provided downstream of the boiler 11, which recirculates part of the flue gas via recirculation ducts 54 and 55 and air valves 52 for reuse in the combustion process. This recirculation device 5 will later with reference to Figures 12 to 17 explained in detail.

Furthermore, the biomass heating system 1 has a fuel supply 6, with which the fuel is conveyed in a controlled manner to the combustion device 2 in the primary combustion zone 26 from the side onto the rotary grate 25. The fuel supply 6 has a cell wheel sluice 61 with a fuel supply opening 65, the cell wheel sluice 61 having a drive motor 66 with control electronics. A driven by the drive motor 66 axis 62 drives a transmission mechanism 63 to the can drive a fuel screw conveyor (not shown) 67 so that the fuel is conveyed in a fuel supply channel 64 to the combustion device 2 .

An ash removal device 7 is provided in the lower part of the biomass heating system 1 , which has an ash discharge screw 71 with a transition screw 73 in an ash discharge channel, which is operated by a motor 72 .

2 now shows a cross-sectional view through the biomass heating system 1 of FIG 1 , which was taken along a section line SL1 and which is shown viewed from the side S. In the corresponding 3 , which has the same cut as 2 represents, for the sake of clarity, the flows of the flue gas and flow cross-sections are shown schematically. to 3 it should be noted that individual areas compared to the 2 are shown grayed out. This is only for clarity 3 and the visibility of the flow arrows S5, S6 and S7.

From left to right are in 2 the combustion device 2, the heat exchanger 3 and an (optional) filter device 4 of the boiler 11 are provided. The boiler 11 is mounted on the boiler base 12 and has a multi-walled boiler housing 13 in which water or another fluid heat exchange medium can circulate. A water circulation device 14 with a pump, valves, lines, etc. is provided for the supply and removal of the heat exchange medium.

The combustion device 2 has a combustion chamber 24 in which the combustion process of the fuel takes place in the core. The combustion chamber 24 has a multi-part rotary grate 25, which will be explained in more detail later, on which the fuel bed 28 rests. The multi-part rotary grate 25 is rotatably mounted by means of a plurality of bearing axles 81 .

Further referring to 2 the primary combustion zone 26 of the combustor 24 is encompassed by (a plurality of) combustor brick(s) 29, with which the combustor bricks 29 define the geometry of the primary combustion zone 26 . The cross-section of the primary combustion zone 26 (for example) along horizontal section line A1 is substantially oval (for example 380mm +/- 60mm x 320mm +/- 60mm; it should be noted that some of the above size combinations may also result in a circular cross-section). The arrows S1 of the corresponding 3 show the primary flow in the primary combustion zone 26 schematically, this primary flow also (not shown) has a twist to improve the mixing of the flue gas. The combustion chamber bricks 29 form the inner lining of the primary combustion zone 26, store heat and are directly exposed to the fire. The combustion chamber stones 29 thus also protect the other material of the combustion chamber 24 , for example cast iron, from the direct effect of the flames in the combustion chamber 24 . The combustion chamber stones 29 are preferably adapted to the shape of the grate 25 . The combustion chamber bricks 29 also have secondary air or recirculation nozzles 291, which recirculate the flue gas into the primary combustion zone 26 for renewed participation in the combustion process. The secondary air nozzles or recirculation nozzles 291 are not aligned with the center of the primary combustion zone 26, but are aligned acentrically in order to cause a swirl of the flow in the primary combustion zone 26 (ie a turbulent flow). The combustion chamber bricks 29 will be explained in more detail later. Insulation 311 is provided at the boiler tube entrance. The oval cross-sectional shape of the primary combustion zone 26 (and the nozzle) advantageously promotes the formation of a turbulent flow.

A secondary combustion zone 27 adjoins the primary combustion zone 26 of the combustion chamber 24 and defines the radiant part of the combustion chamber 24. In the radiant part, the flue gas produced during combustion releases its thermal energy mainly through thermal radiation, in particular to the heat exchange medium, which is located in the two left-hand chambers for the heat exchange medium 38 is located. The corresponding flue gas flow is in 3 indicated by arrows S2 and S3. The first maintenance opening 21 is insulated with an insulating material such as Vermiculite ^™ . The present secondary combustion zone 27 is set up in such a way that burnout of the flue gas is ensured. The special geometric design of the secondary combustion zone 27 will be explained in more detail later. It should be noted that the secondary combustion zone 27 only starts at the level of the corresponding air nozzles from a flow point of view. However, in the present case the secondary combustion zone 27 can structurally also be regarded as the entire space above the primary combustion zone 26 through which a flow can take place.

After the secondary combustion zone 27, the flue gas flows via its inlet 33 into the heat exchange device 3, which has a bundle of boiler tubes 32 provided parallel to one another. The flue gas now flows downwards in the boiler tubes 32, as in 3 indicated by the arrows S4. This part of the flow can also be referred to as the convection part, since the heat dissipation of the flue gas takes place essentially on the boiler tube walls via forced convection. Due to the temperature gradients in the heat exchanger medium, for example in the water, caused in the boiler 11, natural convection of the water occurs, which promotes thorough mixing of the boiler water.

Spring turbulators 36 and spiral or band turbulators 37 are arranged in the boiler tubes 32 in order to improve the efficiency of the heat exchange device 4 .

The outlet of the boiler tubes 32 opens into the turning chamber 35 via the turning chamber inlet 34. The turning chamber 35 is sealed off from the combustion chamber 24 in such a way that no flue gas from the turning chamber 35 can flow directly back into the combustion chamber 24. However, a common (removal) transport path for the combustion residues is provided, which can occur in the entire flow area of the boiler 11. If the filter device 4 is not provided, the flue gas is discharged upwards again in the boiler 11 . The other case of the optional filter device 4 is in the 2 and 3 shown. In the process, the flue gas is fed back up into the filter device 4 after the turning chamber 35 (cf. arrows S5), which in the present example is an electrostatic filter device 4. Flow screens can be provided at the inlet 44 of the filter device 4, which homogenize the flue gas flow.

Electrostatic dust filters, also known as electrostatic precipitators, are devices for separating particles from gases that are based on the electrostatic principle. These filter devices are used in particular for the electrical cleaning of exhaust gases. With electrostatic precipitators, dust particles are electrically charged by a corona discharge and drawn to the oppositely charged electrode. The corona discharge takes place on a suitable, charged high-voltage electrode inside the electrostatic precipitator. The electrode is preferably designed with protruding tips and possibly sharp edges, because the density of the field lines and thus also the electric field strength is greatest there and the corona discharge is thus favored. The opposite electrode usually consists of a grounded section of flue gas or exhaust pipe that is mounted around the electrode. The degree of separation of an electrostatic precipitator depends in particular on the dwell time of the exhaust gases in the filter system and the voltage between the spray and separation electrodes. The rectified high voltage required for this is provided by a high-voltage generating device (not shown). The high-voltage generation system and the holder for the electrode must be protected from dust and dirt in order to avoid unwanted leakage currents and to extend the service life of system 1.

As in 2 shown, a rod-shaped electrode 45 (which is preferably designed like an elongated, plate-shaped steel spring) is held approximately centrally in an approximately chimney-shaped interior of the filter device 4 . The electrode 45 consists at least largely of high-quality spring steel or chromium steel and is held by an electrode holder 43 via a high-voltage insulator, ie an electrode insulation 46 .

The electrode 45 is capable of vibrating and hangs downwards into the interior of the filter device 4. The electrode 45 can, for example, vibrate back and forth transversely to the longitudinal axis of the electrode 45.

A cage 48 simultaneously serves as a counter-electrode and as a cleaning mechanism for the filter device 4. The cage 48 is connected to ground or earth potential. The flue gas or exhaust gas flowing in the filter device 4 is filtered by the prevailing potential difference, cf. the arrows S6, as explained above. In the case of cleaning of the filter device 4, the electrode 45 is switched off. The cage 48 preferably has an octagonal regular cross-sectional profile. The cage 48 can preferably be laser cut during manufacture.

After exiting the heat exchanger 3 (from its exit), the flue gas flows through the turning chamber 34 into the inlet 44 of the filter device 4.

The (optional) filter device 4 is optionally provided fully integrated in the boiler 11, so that the wall surface facing the heat exchanger 3 and flushed through by the heat exchange medium is also used for heat exchange from the direction of the filter device 4, with which the efficiency of the system 1 is further improved. In this way, at least part of the wall of the filter device 4 can be flushed with the heat exchange medium.

The cleaned exhaust gas flows out of the filter device 4 at the filter outlet 47, as indicated by the arrows S7. After leaving the filter, part of the exhaust gas is returned to the primary combustion zone 26 via the recirculation device 5 . This will also be explained in more detail later. This waste gas or flue gas intended for recirculation can also be referred to as “Rezi” or “Rezi gas” for short. The remaining part of the exhaust gas is conducted out of the boiler 11 via the exhaust gas outlet 41 .

An ash discharge 7 is arranged in the lower part of the boiler 11. The ash falling, for example, from the combustion chamber 24, the boiler tubes 32 and the filter device 4 is discharged laterally from the boiler 11 via an ash discharge screw 71.

The boiler 11 of this embodiment was calculated using CFD simulations. Furthermore, practical experiments were carried out to confirm the CFD simulations. The starting point for the considerations were calculations for a 100 kW boiler, although a power range from 20 to 500 kW was taken into account.

A CFD simulation (CFD = Computational Fluid Dynamics = numerical fluid mechanics) is the spatially and temporally resolved simulation of flow and heat conduction processes. The flow processes can be laminar and/or turbulent, accompanied by chemical reactions, or it can be a multi-phase system. CFD simulations are therefore well suited as a design and optimization tool. In the present invention, CDF simulations were used to optimize the fluidic parameters in such a way that the objects of the invention listed above are achieved. In particular, as a result, the mechanical design and dimensioning of the boiler 11 were largely defined by the CFD simulation and also by associated practical experiments. The simulation results are based on a flow simulation taking heat transfer into account.

The components of the biomass heating system 1 and the boiler 11 listed above, which are the result of the CFD simulations, are described in more detail below.

(combustion chamber)

The following statements on the design of the shape of the combustion chamber describe by way of example where the grate according to the invention can be used. The combustion chamber shape and geometry are intended to achieve the best possible turbulent mixing and homogenization of the flow over the cross section of the flue gas duct, minimization of the combustion volume, reduction in excess air and the recirculation ratio (efficiency, operating costs), reduction in CO emissions and of NOx emissions, a reduction of Temperature peaks (fouling and slagging) and a reduction in flue gas velocity peaks (material stress and erosion).

the 4 showing a partial view of the 2 is, and the figure 5 , which is a sectional view through the boiler 11 along the vertical section line A2, represent a combustion chamber geometry that meets the above-mentioned requirements for biomass heating systems over a wide power range of, for example, 20 to 500 kW.

$$\mathrm{BK2}=300\mathrm{mm}+-50\mathrm{mm},\mathrm{vorzugsweise}+-30\mathrm{mm};$$

$$\mathrm{BK3}=430\mathrm{mm}+-80\mathrm{mm},\mathrm{vorzugsweise}+-40\mathrm{mm};$$

$$\mathrm{BK4}=538\mathrm{mm}+-80\mathrm{mm},\mathrm{vorzugsweise}+-50\mathrm{mm};$$

$$\mathrm{BK5}=\left(\mathrm{BK3}-\mathrm{BK2}\right)/2=\mathrm{bspw}.65\mathrm{mm}+-30\mathrm{mm},\mathrm{vorzugsweise}+-20\mathrm{mm};$$

$$\mathrm{BK6}=307\mathrm{mm}+-50\mathrm{mm},\mathrm{vorzugsweise}+-20\mathrm{mm};$$

$$\mathrm{BK7}=82\mathrm{mm}+-20\mathrm{mm},\mathrm{vorzugsweise}+-20\mathrm{mm};$$

$$\mathrm{BK8}=379\mathrm{mm}+-40\mathrm{mm},\mathrm{vorzugsweise}+-20\mathrm{mm};$$

$$\mathrm{BK9}=470\mathrm{mm}+-50\mathrm{mm},\mathrm{vorzugsweise}+-20\mathrm{mm};$$

$$\mathrm{BK10}=232\mathrm{mm}+-40\mathrm{mm},\mathrm{vorzugsweise}+-20\mathrm{mm};$$

$$\mathrm{BK11}=380\mathrm{mm}+-60\mathrm{mm},\mathrm{vorzugsweise}+-30\mathrm{mm};$$

$$\mathrm{BK12}=460\mathrm{mm}+-80\mathrm{mm},\mathrm{vorzugsweise}+-30\mathrm{mm}.$$

The in the Figures 3 and 4 The dimensions specified and determined via CFD calculations and practical experiments are as follows: $$\mathrm{BK1}=172\mathrm{mm}+-40\mathrm{mm},\mathrm{preferably}+-17\mathrm{mm};$$

$$\mathrm{BK2}=300\mathrm{mm}+-50\mathrm{mm},\mathrm{preferably}+-30\mathrm{mm};$$

$$\mathrm{BK3}=430\mathrm{mm}+-80\mathrm{mm},\mathrm{preferably}+-40\mathrm{mm};$$

$$\mathrm{BK4}=538\mathrm{mm}+-80\mathrm{mm},\mathrm{preferably}+-50\mathrm{mm};$$

$$\mathrm{BK5}=\left(\mathrm{BK3}-\mathrm{BK2}\right)/2=\mathrm{e.g}.65\mathrm{mm}+-30\mathrm{mm},\mathrm{preferably}+-20\mathrm{mm};$$

$$\mathrm{BK6}=307\mathrm{mm}+-50\mathrm{mm},\mathrm{preferably}+-20\mathrm{mm};$$

$$\mathrm{BK7}=82\mathrm{mm}+-20\mathrm{mm},\mathrm{preferably}+-20\mathrm{mm};$$

$$\mathrm{BK8}=379\mathrm{mm}+-40\mathrm{mm},\mathrm{preferably}+-20\mathrm{mm};$$

$$\mathrm{BK9}=470\mathrm{mm}+-50\mathrm{mm},\mathrm{preferably}+-20\mathrm{mm};$$

$$\mathrm{BK10}=232\mathrm{mm}+-40\mathrm{mm},\mathrm{preferably}+-20\mathrm{mm};$$

$$\mathrm{BK11}=380\mathrm{mm}+-60\mathrm{mm},\mathrm{preferably}+-30\mathrm{mm};$$

$$\mathrm{BK12}=460\mathrm{mm}+-80\mathrm{mm},\mathrm{preferably}+-30\mathrm{mm}.$$

However, these dimensions are only exemplary and serve to clarify the present technical teaching.

In the present case, both the geometries of the primary combustion zone 26 and the secondary combustion zone 27 of the combustion chamber 24 for a 100 kW boiler 11 can be optimized with these values. The specified size ranges are ranges with which the requirements are (approximately) fulfilled as well as with the specified exact values.

A chamber geometry of the primary combustion zone 26 of the combustion chamber 24 (or an inner volume of the primary combustion zone 26 of the combustion chamber 24) can preferably be defined using the following basic parameters: A volume with an oval horizontal base area measuring 380 mm +/- 60 mm (preferably +/- 30mm) x 320 mm +- 60 mm (preferably +-30mm), and a height of 538 mm +- 80 mm (preferably +- 50 mm).

As a further development, the volume defined above can have an upper opening in the form of a combustion chamber nozzle 203, which opens into the secondary combustion zone 27 of the combustion chamber 24, which has a combustion chamber slope 202 protruding into the secondary combustion zone 27, which preferably contains the heat exchange medium 38. The combustion chamber slope 202 reduces the cross section of the secondary combustion zone 27 by at least 5%, preferably by at least 15% and even more preferably by at least 19%.

The combustion chamber slope 202 serves to homogenize the flow S3 in the direction of the heat exchanger 3 and thus the flow through the boiler tubes 32.

Combustors having a rectangular or polygonal combustor and nozzle are common in the prior art, however, the irregular shape of the combustor and nozzle presents another impediment to even air distribution and good mixing of air and fuel, as has been recognized herein.

Therefore, in the present case, the combustion chamber 24 is provided without dead corners or dead edges.

It was thus recognized in the present case that the geometry of the combustion chamber (and the entire course of flow in the boiler) plays a decisive role in the considerations for optimizing the biomass heating system 1 . Therefore (a departure from the usual rectangular or polygonal shapes) the oval described herein or round basic geometry without dead corners. In addition, this basic geometry of the combustion chamber and its structure has been optimized with the dimensions/dimensional ranges specified above. These dimensions/dimensional ranges are selected in such a way that, in particular, different fuels (wood chips and pellets) with different qualities (for example with different water contents) can also be burned with a very high level of efficiency. This was the result of practical tests and CFD simulations.

In particular, the primary combustion zone 26 of the combustion chamber 24 can comprise a volume which preferably has an oval or approximately circular horizontal cross-section on the outer circumference (such a cross-section is shown in 2 marked with A1 as an example). This horizontal cross section can also preferably represent the base area of the primary combustion zone 26 of the combustion chamber 24 . The combustion chamber 24 can have an approximately constant cross section over the height indicated by the double arrow BK4. In this respect, the primary combustion zone 24 can have an approximately oval-cylindrical volume. Preferably, the side walls and base (grate) of the primary combustion zone 26 may be perpendicular to one another.

The term "approximately" is used above because of course individual notches, design-related deviations or small asymmetries can be present, for example at the transitions of the individual combustion chamber bricks 29 to one another. However, these minor deviations only play a subordinate role in terms of flow technology.

The horizontal cross section of the combustion chamber 24 and in particular of the primary combustion zone 26 of the combustion chamber 24 can also preferably be regular. Further, the horizontal cross-section of the combustor 24, and particularly the primary combustion zone 26 of the combustor 24, may preferably be a regular (and/or symmetrical) ellipse.

In addition, the horizontal cross section (the outer circumference) of the primary combustion zone 26 can be designed to be constant over a predetermined height, for example 20 cm.

An oval-cylindrical primary combustion zone 26 of the combustion chamber 24 is thus provided in the present case, which, according to CFD calculations, enables a significantly more uniform and better air distribution in the combustion chamber 24 than in the case of rectangular combustion chambers of the prior art. The lack of dead spaces also avoids zones in the combustion chamber with poor air flow, which increases efficiency and reduces slag formation.

Likewise, the nozzle 203 between the primary combustion zone 26 and the secondary combustion zone 27 is designed as an oval or approximately circular constriction in order to also optimize the flow conditions. The swirl of the flow in the primary combustion zone 26 explained above leads to a helix-shaped flow path directed upwards, with an equally oval or approximately circular nozzle promoting this flow path and not disturbing it like conventional rectangular nozzles. This optimized nozzle 203 concentrates the air flowing upwards and ensures an even flow into the secondary combustion zone 27. This improves the combustion process and increases efficiency.

In addition, the course of the flow in the secondary combustion zone 27 and from the secondary combustion zone 27 to the boiler tubes 32 is presently optimized, as explained in more detail below.

The combustion chamber slope 202 of 4 , which without a reference number in the 2 and 3 can be seen and where the combustion chamber 25 (or its cross-section) tapers at least approximately linearly from bottom to top, according to CFD calculations ensures that the flue gas flow in the direction of the heat exchange device 4 is made more uniform, which means that its efficiency can be improved. The horizontal cross-sectional area of the combustion chamber 25 tapers from beginning to end End of the combustion chamber slope 202 preferably at least 5%. The combustion chamber slope 202 is provided on the side of the combustion chamber 25 to the heat exchange device 4 and is provided rounded at the point of maximum narrowing. Parallel or straight combustion chamber walls without a taper (so as not to impede the flue gas flow) are common in the prior art.

The deflection of the flue gas flow upstream of the tube bundle heat exchanger is designed in such a way that an uneven flow onto the tubes is avoided as far as possible, with the result that temperature peaks in individual boiler tubes 32 can be kept low. As a result, the efficiency of the heat exchange device 4 is improved.

In detail, the gaseous volume flow of the flue gas is conducted through the sloping combustion chamber wall at a uniform speed (even in the case of different combustion states) to the heat exchanger tubes or the boiler tubes 32 . This results in a uniform heat distribution of the individual boiler tubes 32 relevant heat exchanger surfaces. The exhaust gas temperature is thus reduced and the efficiency increased. The flow distribution is particularly at the in the 3 shown indicator line WT1 much more evenly than in the prior art. The line WT1 represents an entry area for the heat exchanger 3. The indicator line WT3 indicates an exemplary cross-sectional line through the filter device 4, in which the flow is set up as homogeneously as possible (due to flow screens at the entrance of the filter device 4 and due to the geometry the turning chamber 35).

Furthermore, an ignition device 201 is provided in the lower part of the combustion chamber 25 on the fuel bed 28 . This can cause initial ignition or re-ignition of the fuel. The ignition device 201 can be a glow igniter. The ignition device is advantageously stationary and offset laterally horizontally to the location where the fuel is poured.

Furthermore, a lambda probe (not shown) can (optionally) be provided after the exit of the flue gas (ie after S7) from the filter device. through the

Lambda probe, a controller (not shown) can detect the respective calorific value. The lambda probe can thus ensure the ideal mixing ratio between the fuels and the oxygen supply. Despite different fuel qualities, the result is high efficiency and higher efficiency.

This in figure 5 The fuel bed 28 shown shows an exemplary fuel distribution due to the delivery of the fuel from the right side of the figure 5 . This fuel bed 28 is flown from below with a mixture of flue gas and fresh air, which is provided by the recirculation device 5 . This flue gas/fresh air mixture is advantageously pre-tempered and has the ideal quantity (mass flow) and the ideal mixing ratio, as regulated by a system controller (not shown in detail) on the basis of various measured values recorded by sensors and associated air valves 52 .

Next is in the 4 and 5 a combustor nozzle 203 is shown separating the primary combustion zone 26 from the secondary combustion zone 27 and accelerating and focusing the flue gas flow. As a result, the flue gas flow is better mixed and can burn more efficiently in the secondary combustion zone 27 . The area ratio of combustor nozzle 203 ranges from 25% to 45%, but is preferably 30% to 40%, and is ideally 36% +/- 1% (ratio of measured entrance area to measured exit area of nozzle 203).

Consequently, the above information on the combustion chamber geometry of the primary combustion zone 26 together with the geometry of the nozzle 203 represents an advantageous development of the present disclosure.

(combustion chamber bricks)

the 6 shows a three-dimensional sectional view (obliquely from above) of the primary combustion zone 26 of the combustion chamber 24 with the rotary grate 25, and in particular on the special design of the combustion chamber bricks 29. The 7 shows according to 6 an exploded view of the combustion chamber bricks 29. The views of 6 and 7 can preferably with the dimensions listed above 4 and 5 be executed. However, this is not necessarily the case.

The chamber wall of the primary combustion zone 26 of the combustor 24 is provided with a plurality of combustor bricks 29 in a modular construction which, among other things, facilitates manufacture and maintenance. Maintenance is facilitated in particular by the possibility of removing individual combustion chamber bricks 29.

Form-fitting grooves 261 and projections 262 (in 6 to avoid redundancies in the figures, only a few of these are designated by way of example) are provided in order to create a mechanical and largely airtight connection, in order in turn to prevent the ingress of disturbing external air. Preferably, every two at least largely symmetrical combustion chamber blocks (with the possible exception of the openings for the Rezi gas) form a complete ring. Furthermore, three rings are preferably stacked on top of one another in order to form the primary combustion zone 26 of the combustion chamber 24 which is oval-cylindrical or alternatively at least approximately circular (the latter is not shown).

Three further combustion chamber bricks 29 are provided as the upper closure, with the annular nozzle 203 being supported by two retaining bricks 264 which are placed on the upper ring 263 in a form-fitting manner. All bearing surfaces 260 have grooves 261 either for mating projections 262 and/or for the insertion of suitable sealing material.

The mounting stones 264, which are preferably symmetrical, can preferably have an inwardly inclined bevel 265 in order to make it easier for fly ash to be swept away onto the rotary grate 25.

The lower ring 263 of the combustion chamber bricks 29 rests on a base plate 251 of the rotary grate 25 . Ash is increasingly deposited on the inner edge between this lower ring 263 of the combustion chamber bricks 29 , which advantageously independently and advantageously seals this transition during operation of the biomass heating system 1 .

The (optional) openings for the recirculation nozzles 291 are provided in the middle ring of the combustion chamber bricks 29 .

Three rings of combustor bricks 29 are provided here, as this represents the most efficient way of manufacture and also of maintenance. Alternatively, two, four or five (2, 4 or 5) such rings can also be provided.

The combustion chamber bricks 29 are preferably made of high-temperature silicon carbide, which makes them very wear-resistant.

The combustion chamber bricks 29 are provided as molded bricks. The combustion chamber bricks 29 are shaped in such a way that the interior volume of the primary combustion zone 26 of the combustion chamber 24 has an oval horizontal cross section, which means that dead corners or dead spaces, which are usually not optimally flowed through by the primary air, are avoided by an ergonomic shape, as a result of which the fuel present there is not optimal is burned. Due to the existing shape of the combustion chamber bricks 29, the flow of primary air and consequently the efficiency of the combustion is improved.

The oval horizontal cross section of the primary combustion zone 26 of the combustion chamber 24 is preferably a point-symmetrical and/or regular oval with the smallest inside diameter BK3 and the largest inside diameter BK11. These measurements were the result of optimizing the primary combustion zone 26 of the combustor 24 using CFD simulation and field testing.

(rotary grate)

8 shows a plan view of the rotary grate 25 from above seen from the section line A1 of FIG 2 to illustrate various fundamentally possible operating states of rotary grate 25.

The supervision of 8 can preferably be designed with the dimensions listed above. However, this is not necessarily the case.

The rotary grate 25 has the base plate 251 as a base element. A transition element 255 is provided in a roughly oval-shaped opening in the base plate 251, which bridges a gap between a first rotary grate element 252, a second rotary grate element 253 and a third rotary grate element 254, which are rotatably mounted. Thus, the rotary grate 25 is provided as a rotary grate with three individual elements, i. H. this can also be referred to as a triple rotary grate. Air holes are provided in the rotary grate elements 252, 253 and 254 for primary air to flow through.

The rotary grate elements 252, 253 and 254 are flat and heat-resistant metal plates, for example made of cast metal, which have an at least largely planar configured surface on the upper side and are connected to the bearing axles 81 on the lower side, for example via intermediate mounting elements. When viewed from above, rotating grate elements 252, 253 and 254 have curved and complementary sides or contours.

In particular, the rotating grate elements 252, 253, 254 can have mutually complementary and curved sides, with the second rotating grate element 253 preferably having concave sides to the adjacent first and third rotating grate elements 252, 254, and preferably the first and third rotating grate elements 252, 254 to the respective second rotary grate element 253 has a convex side. This improves the crushing function of the rotary grate elements, as the length of the fracture is increased and the forces acting to break (similar to scissors) act in a more targeted manner.

$$\mathrm{DR2}=350\mathrm{mm}+-60\mathrm{mm},\mathrm{bevorzugt}+-20\mathrm{mm}$$

The rotary grate elements 252, 253 and 254 (and their enclosure in the form of the transition element 255) have an approximately oval outer shape when viewed together, which in turn avoids dead corners or dead spaces in which suboptimal combustion could take place or ash could accumulate could accumulate undesirably. The optimal dimensions of this outer shape of the rotating grate elements 252, 253 and 254 are in 8 denoted by the double arrows DR1 and DR2. Preferably, but not exclusively, DR1 and DR2 are defined as follows: $$\mathrm{DR1}=288\mathrm{mm}+-40\mathrm{mm},\mathrm{preferred}+-20\mathrm{mm}$$

$$\mathrm{DR2}=350\mathrm{mm}+-60\mathrm{mm},\mathrm{preferred}+-20\mathrm{mm}$$

These values have turned out to be optimal values (ranges) in the CFD simulations and the following practical test. These dimensions correspond to those of

4 and 5 . These dimensions are particularly advantageous for the combustion of different fuels or the fuel types wood chips and pellets (hybrid firing) in a power range of 20 to 200 kW.

The rotary grate 25 has an oval combustion surface 258 which is more favorable for fuel distribution, air flow through the fuel and combustion of the fuel than a conventional rectangular combustion surface. The combustion surface 258 is formed at the core by the surfaces of the rotary grate members 252, 253 and 254 (in the horizontal state). The combustion surface is therefore the upward-pointing surface of the rotary grate elements 252, 253 and 254. This oval combustion surface advantageously corresponds to the fuel support surface when the fuel is applied or pushed laterally onto the rotary grate 25 (cf. arrow E of 9 , 10 and 11 ). In particular, the fuel can be supplied from a direction which is parallel to a longer central axis (main axis) of the oval combustion surface of the rotary grate 25 .

The first rotary grate element 252 and the third rotary grate element 254 can preferably be configured identically in their combustion surface 258 . Next lets do the first

Rotating grate element 252 and the third rotating grate element 254 may be identical or structurally identical to one another. For example, this is in 9 1, with the first rotating grate element 252 and the third rotating grate element 254 having the same shape.

Furthermore, the second rotary grate element 253 is arranged between the first rotary grate element 252 and the third rotary grate element 254 .

The rotary grate 25 is preferably provided with an approximately point-symmetrical, oval combustion surface 258 .

Likewise, the rotary grate 25 can form an approximately elliptical or oval combustion surface 258, with DR2 being the dimensions of its major axis and DR1 being the dimensions of its minor axis.

Furthermore, the rotary grate 25 can have an approximately oval combustion surface 258 which is axisymmetric with respect to a central axis of the combustion surface 258 .

Furthermore, the rotary grate 25 can have an approximately circular combustion surface 258, which entails minor disadvantages in fuel supply and distribution.

Two motors or drives 231 of the rotary mechanism 23 are also provided, with which the rotary grate elements 252, 253 and 254 can be rotated accordingly. More about the special function and the advantages of the present rotary grate 25 is later with reference to the figures 9 , 10 and 11 described.

In the case of pellet heating systems in particular, failures due to slag formation in the combustion chamber 24, in particular on the rotary grate 25, can increasingly occur. Slag is always produced during a combustion process when temperatures above the ash melting point are reached in the embers. The ash then softens, sticks together and, after cooling, forms solid, dark-colored slag. This also as sintering designated process is undesirable in the biomass heating system 1, since the accumulation of slag in the combustion chamber 24 can lead to a malfunction: it switches off. The combustion chamber 24 usually has to be opened and the slag removed.

The ash melting point depends very much on the fuel used. Spruce wood, for example, has an ash melting point of around 1200 °C. But the ash melting point of a fuel can also vary greatly. Depending on the quantity and composition of the minerals contained in the wood, the behavior of the ash changes during the combustion process.

Another factor that can influence slag formation is the transport and storage of the wood pellets or chips. This is because they should reach the combustion chamber 24 as undamaged as possible. If the wood pellets have already crumbled when they enter the combustion process, this increases the density of the ember bed. The result is more slag formation. In particular, the transport from the storage room to the combustion chamber 24 is of importance here. Particularly long distances, as well as curves and angles, lead to damage to the wood pellets. There is thus a problem in that the formation of slag cannot be completely avoided due to the large number of influencing factors described above.

Another factor relates to the control of the combustion process. So far, efforts have been made to keep the temperatures rather high in order to achieve the highest possible burnout and low emissions. An optimized combustion chamber geometry and geometry of the combustion zone 258 of the rotary grate 25 makes it possible to keep the combustion temperature lower and thus reduce slag formation.

In addition, the resulting slag (and also the ash) can advantageously be removed due to the special shape and the functionality of the present rotary grate 25 . This will now be related to the figures 9 , 10 and 11 explained in more detail.

the figures 9 , 10 and 11 show a three-dimensional view of the rotary grate 25 with the base plate 251, the first rotary grate element 252, the second rotary grate element 253 and the third rotary grate element 254. The views of FIG 9 , 10 and 11 can preferably correspond to the dimensions listed above. However, this is not necessarily the case.

This view shows the rotary grate 25 as a free slide-in part with rotary grate mechanism 23 and drive(s) 231. The rotary grate 25 is mechanically provided in such a way that it can be individually prefabricated in the manner of the modular system, and as a slide-in part inserted into a provided elongated opening of the boiler 11 and can be installed. This also facilitates the maintenance of this wear-prone part. The rotary grate 25 can thus preferably have a modular design, in which case it can be quickly and efficiently removed and reinserted as a complete part with rotary grate mechanism 23 and drive 231 . The modularized rotary grate 25 can thus also be assembled and disassembled using quick-release fasteners. In contrast, prior art rotary grates are typically permanently mounted and thus difficult to maintain or assemble.

The drive 231 can have two separately controllable electric motors. These are preferably provided on the side of the rotating grate mechanism 23 . The electric motors can have reduction gears. Furthermore, end stop switches can be provided which provide end stops for the end positions of the rotating grate elements 252, 253 and 254 respectively.

The individual components of the rotary grate mechanism 23 are intended to be exchangeable. For example, the gears are provided to be plugged. This facilitates maintenance and also a side change of the mechanics during assembly, if necessary.

In the rotary grate elements 252, 253 and 254 of the rotary grate 25, the openings 256 already mentioned are provided. The rotary grate elements 252, 253 and 254 can each be rotated by at least 90° via their respective bearing axles 81, which are driven via the rotary mechanism 23 by the drive 231, in this case the two motors 231 degrees, preferably at least 120 degrees, even more preferably 170 degrees, about the respective bearing or rotation axis 81 . The maximum angle of rotation can be 180 degrees or a little less than 180 degrees, as the grate lips 257 allow. A free rotation of 360 degrees is also conceivable if no rotation-limiting grate lips are provided. The rotary mechanism 23 is set up in such a way that the third rotary grate element 254 can be rotated individually and independently of the first rotary grate element 252 and the second rotary grate element 243, and that the first rotary grate element 252 and the second rotary grate element 243 are rotated together and independently of the third rotary grate element 254 be able. The rotary mechanism 23 can be provided accordingly, for example by means of running wheels, toothed or drive belts and/or gears.

The rotary grate elements 252, 253 and 254 can preferably be produced as a cast grate with a laser cut in order to ensure precise shape retention. This in particular in order to define the air flow through the fuel bed 28 as precisely as possible and to avoid disruptive air currents, for example strands of air at the edges of the rotary grate elements 252, 253 and 254.

The openings 256 in the rotating grate elements 252, 253 and 254 are arranged in such a way that they are small enough for the usual pellet material and/or the usual wood chips not to fall through and large enough for the fuel to flow well with air can be.

9 now shows the rotary grate 25 in the closed position or in a working position, with all rotary grate elements 252, 253 and 254 being aligned horizontally or closed. This is the position in normal operation. The uniform arrangement of the large number of openings 256 ensures a uniform flow through the fuel bed 28 (this is shown in 9 not shown) on the rotary grate 25 ensured. In this respect, the optimal combustion state can be produced here. The fuel is applied to the rotary grate 25 from the direction of arrow E; to that extent the fuel from the right side of the 9 pushed up onto the rotary grate 25.

During operation, ash and/or slag accumulates on the rotary grate 25 and in particular on the rotary grate elements 252, 253 and 254. With the present rotary grate 25, the rotary grate 25 can be cleaned efficiently (for the ash removal 7 explained later).

10 shows the rotary grate in the state of a partial cleaning of the rotary grate 25 in ember maintenance mode. To this end, only the third rotating grate element 254 is rotated. Because only one of the three rotary grate elements is rotated, the embers are retained on the first and second rotary grate elements 252, 253, while at the same time the ash and slag can fall out of the combustion chamber 24 downwards. As a result, no external ignition is required to resume operation (this saves up to 90% ignition energy). A further consequence is a reduction in wear on the ignition device (for example an ignition rod) and a saving in electricity. Ash cleaning can also advantageously take place during operation of the biomass heating system 1 .

10 also shows a state of ember maintenance during a (often already sufficient) partial cleaning. The operation of the system 1 can thus advantageously take place more continuously, which means that, in contrast to the usual full cleaning of a conventional grate, there is no need for lengthy, complete ignition, which can take several tens of minutes.

In addition, a potential slag on the two outer edges of the third rotary grate element 254 is broken up (opened) during the rotation thereof, with the curved outer edges of the third rotary grate element 254 not only shearing off over a greater overall length than with conventional rectangular elements of the prior art , but also with an uneven distribution of movement in relation to the outer edge (there is more movement in the middle than at the bottom and top edges). The breaker function of the rotating grate 25 is thus significantly strengthened.

In 10 grate lips 257 (on both sides) of the second rotary grate element 253 can be seen. These grate lips 257 are set up in such a way that the first rotary grate element 252 and the third rotary grate element 254 rest on the upper side of the grate lips 257 in the closed state, and thus the rotary grate elements 252, 253 and 254 are provided with no gaps relative to one another and are therefore provided in a sealing manner. This avoids strands of air and undesired primary air flows through the bed of embers. This advantageously improves the efficiency of the combustion.

11 shows the rotary grate 25 in the state of universal cleaning or in an open state, which is preferably carried out during a plant standstill. All three rotary grate elements 252, 253 and 254 are rotated, with the first and second rotary grate element 252, 253 preferably being rotated in the opposite direction to the third rotary grate element 254. On the one hand, the rotary grate 25 is completely emptied, and on the other hand, the slag is removed now broken on four odd outer edges. In other words, an advantageous 4-fold breaker function is realized. The above in relation to 9 What is explained with regard to the geometry of the outer edges also applies with regard to 10 .

In summary, the present rotary grate 25 realizes in addition to normal operation (cf. 9 ) advantageously two different types of cleaning (cf. 10 and 11 ), whereby the partial cleaning allows a cleaning during the operation of the plant 1.

In comparison, commercially available rotary grate systems are not ergonomic and have disadvantageous dead corners due to their rectangular geometry, in which the primary air cannot optimally flow through the fuel. At these corners, slag formation accumulates. This ensures poorer combustion with poorer efficiency.

The existing simple mechanical structure of the rotary grate 25 makes it robust, reliable and durable.

(rotary grate with an improved cleaning device)

The inventor of the present application has made investigations to improve the cleaning device of the (in-house and post-published) prior art EP 3 789 676 B1 made, the results of these investigations below with reference to 22 be explained. During these investigations, the biomass heating system 1 was put into operation, and regular stocktaking and chemical investigations were carried out on the ash and slag residues on rotary grate 25.

The rotary grate 25 of the prior art has 4 cleaning devices 125 according to the falling hammer principle with a rotatably mounted mass element for striking a stop of the rotary grate, with two cleaning devices 125 being provided on the middle rotary grate element 253 and one each on the left and right rotary grate elements 252 and 254. When the rotary grate elements 252, 253, 254 rotate, the mass element of these cleaning devices strikes in certain areas which are roughly indicated by the lightly hatched circles 299. In these areas 299 there is a really good cleaning effect, also because the attack takes place immediately. In the heavily hatched areas (which are only roughly indicated), however, the cleaning effect is not so optimal, also because the respective impact on the rotary grate 25 by the cleaning device 125 does not take place immediately, and the impact impulse thus only spreads (damped) through the grate got to. In other words, at the points of the grate which are arranged away from the direct impact of the four mass elements on the respectively associated stops, only a strongly damped vibration or only a damped impact takes place. Thus, the cleaning effect in the areas 298 was not optimal or the grate 25 is only partially cleaned.

However, the specific incineration or slagging of the grate and the less than optimal cleaning effect could not be explained solely by means of the positions of the respective stop of the mass element. In particular, the openings 256 in the central area 297 of the grate were clogged, with here at the Studies, however, even provided two adjacent stops for two mass elements of two cleaning devices. Thus, the damping effect described above alone cannot be held responsible for the non-optimal cleaning of the grate 25.

During the investigations it was also observed that the openings 256 slowly close from the edge and that a kind of ash or slag edge first forms at the openings 256 . The ash or slag forms a layer which grows inwards from the edges of the openings 256, with a layer of slag being formed which, however, does not cover the depths of the openings 256.

A wet chemical analysis of the ash deposits at the openings 256 showed that these consist primarily of potassium (K) and calcium (Ca). Relevant parts of both elements occur as carobates, with which high TIC contents (inorganic carbon = carbonate carbon) were determined in the ash. It was found that ash deposits from the surface of the grate 25 (and away from the openings 256) have a 1.6 to 1.8 times the TIC content compared to ash deposits at the openings 256 of the grate 25. This means that the calcium and potassium carbonate content of the ash on the surface of the grate 25 is again significantly higher than on and above the openings 256.

The molar potassium/calcium ratio is well below 1 for the ash samples from the openings 256 and just above 1 for the ash samples from the surface of the grate 25.

Using thermodynamic high-temperature equilibrium calculations, potassium and calcium can form double carbonates in the temperature range below approx. 800°C (K ₂ Ca ₂ (CO ₃ ) ₂ and K ₂ CO ₃ (CO ₂ ) ₂ ). At potassium/calcium ratios of >1, the proportion of K ₂ CO ₃ in the ash increases. K ₂ CO ₃ can form melting phases in the temperature range from approx. 1000°C. However, it should be noted that the results of these calculations only provide rough guide values, since they depend on the surrounding gas phase composition (reducing, oxidizing, CO ₂ content).

The different carbonate contents of the ash deposits on the grate 25 and at the openings 25 can be explained by different dwell times and gas atmospheres, since the CO ₂ content is in the areas in which no air acts (ie away from the openings 256 for the air flow). in the gas is usually even higher.

Potassium and calcium carbonates form on the grate due to the largely substoichiometric conditions in the fuel bed 28 and the CO ₂ present in the gas or air. At high temperatures, due to the incipient melting of the ash, these can form sintering or even local melting phases. With such sintering, the ash particles begin to combine to form a planar lattice, which builds up as a result and the openings 256 can close. This sintering has the property that it breaks apart over a large area when force is applied, since the lattice structure is destroyed. Conversely, however, an indirect impact on the sintering often has little effect, since its adhesion to the rust as a flat structure is too large for efficient cleaning.

In addition, there is the fact that the extent of carbonate formation and the occurrence of sintering are dependent on the fuel. For example, it has been observed that sintering can occur to a large extent when pellets are used as fuel, while sintering does not occur or only occurs to an insignificant extent when, for example, wood chips are used as fuel. In this respect, the issue at hand is a special one, which affects certain fuels (especially those with a higher density) more than others.

In summary, it was recognized that, depending on the fuel, different chemistry forms at the openings 256 and on the grate 25 (remote from the openings) with regard to incineration or slagging, which means that the mechanical properties of the respective incineration or slagging are also different. This means that fuel-flexible furnaces have the additional special problem that some of the ash or slag deposits occur with certain fuels, but not or to a far lesser extent with others. With that one has to Fuel-independent cleaning of the grate must be guaranteed, whereby the cleaning must work even if the type of sintering or slagging varies greatly.

Furthermore, it was recognized that particularly over the openings 256 disruptive areal sinterings are formed, which cannot be efficiently cleaned off by means of a conventional knocking action.

In the following, with reference to the Figures 12a to 12d a first general example of the principle according to the invention of a cleaning device 125 for a rotary grate 25 is explained, which takes the above knowledge into account.

In 12a a rotary grate 25 with a rotary grate element 252 is shown in a first state. In this first state, the closed position or the working position of the 9 may correspond, the combustion surface 258 is oriented approximately horizontally. In the first condition, the fuel may lie on the combustion surface 258 for combustion.

The dash-dot line of the 12a indicates an example horizontal line H. This is at least approximately perpendicular to the direction of the gravitational acceleration. The working position of the rotating grate 25 or the rotating grate element 252 can be based on this horizontal line H, with the combustion surface 258 being aligned at least approximately parallel to the horizontal line H.

The rotary grate element 252 is rotatably mounted by means of a bearing shaft 81, in the present case with a rectangular cross section, shown as an example. One of the directions of rotation is indicated by the arrow D1. The axis of rotation of the bearing shaft 81 is in 12a marked with a circle with a dot inside the bearing shaft 81. The bearing shaft 81 supports the rotary grate element 252 , it being possible for the rotary grate element 252 to be fixed on the bearing shaft 81 . Alternatively (not shown), the bearing shaft can also be provided on the side of the rotary grate element 252 , or (not shown) the bearing shaft 81 can be an integral part of the rotary grate element 252 .

The bearing shaft 81 is in turn rotatably mounted relative to the biomass heating system 1 . The rotation of the bearing shaft 81 and thus of the rotary grate element 252 takes place via a (in the Figures 12a to 12d drive device (not shown for the sake of simplicity), for example via an electric motor 231.

The coupling between the drive device and the bearing shaft 81 can preferably be flexible and not rigid. For example, the coupling can take place by means of a flexible toothed belt. The coupling can also take place by means of a toothed gear with play.

The cleaning device 125 is attached to the bearing shaft 81 of the rotary grate element 252 . Alternatively (not shown), the cleaning device 125 can also be attached directly to the rotary grate element 252 . The bearing shaft 81 has a (geometric) axis of rotation 832 about which the rotary grate element 252 is rotated.

The cleaning device 125 is provided on the underside of the rotary grate element 252 . The cleaning device 125 can hang freely on the rotary grate element 252 without touching other parts of the biomass heating system 1 .

The cleaning device 125 has a suspension 122 with a joint 123 . The suspension 112 extends away from the rotary grate element 252 and spaces the joint 123 from the bearing shaft 81.

The joint 123 provides an axis of rotation for a beating arm 124 which is rotatably mounted by the joint 123 in relation to the longitudinal extent of the beating arm 124 approximately centrally. The striking arm 124 is elongate and has, for example, the shape of a rod or shaft. The striking arm 124 has a first end 124a and a second end 124b. The second end 124b may provide a striking arm head 126 for striking against a striking surface 128b.

At the first end 124a of the beater arm 124, a mass member 127 is attached. The mass element 127 is preferably made of a metal and can serve as a weight and also as an impact element in the sense of a hammer head. In this respect, the mass element 127 can also represent a striking arm head 126 .

The mass element 127 itself can be provided in one piece or also in several pieces. For example, the mass element 127 can be a single cast element, or it can consist of several pieces of metal that are welded or bolted together. The mass element 127 can also be provided in one piece or in several pieces with the striking arm 124 . For example, the mass element 127 can be manufactured with the beater arm 124 as a single casting.

The impact arm 124 with the mass element 127 of Figures 12a to 12d can also be referred to as a drop hammer.

At least one lancing element 129 with projections 130 is also provided on the striking arm head 126 or on the mass element. The piercing element 129 is set up in such a way that its projections 130 can penetrate into a (preferably slot-shaped) opening 256 of the rotating grate element 252 . The projections 130 can preferably be designed to taper towards the end of the projections 130 . In other words, the projections 130 can be provided in such a way that they taper (preferably continuously) towards their distal end or are provided in the shape of a wedge.

Furthermore, the at least one lancing element 129 is designed with its projections 130 in the shape of a comb. Thus, several projections (130) are provided next to each other in a row.

A bevel is provided at the second end 124b of the hammer arm 124, with which a hammer arm head 126 is provided with a surface which, in the first state, rests flat on the underside of the rotary grate element 252 or on a stop surface 128b of the rotary grate element 252.

This limits the maximum deflection of the impact arm 123 with the mass element 127 in one direction. In other words, the mass element 127, which is attached to the beating arm 124, is arranged at a maximum distance from the rotary grate element 252. Due to the weight of the mass element 127, the beating arm 124 remains stable in the in position in the first state 12a position shown in its starting position.

the inside 12a The angle η shown with its dashed legs indicates the range of movement of the beating arm 124 . In other words, the cleaning device 215 is set up in such a way that the beating arm 124 can move freely in this angular range η. Advantageously, however, no dedicated or separate drive is provided for this purpose. Rather, the drive for rotating the rotary grate element 252 is also used indirectly for the function of the cleaning device 125 and thus for knocking off the rotary grate 25 . Due to the position of the beater arm and the defined angular range η, the rotating grate 25 is knocked off precisely when the rotating grate 25 is rotated to clean combustion residues. In other words, the drop starting point of the drop hammer configuration can be mechanically arranged such that the rotating grate 25 is tapped off when the combustion surface 258 overhangs downward.

In the first state, for example, the combustion of the fuel can take place on the combustion surface 258 of the rotary grate element 252 . Combustion residues, including ash and slag, remain on the grate. These combustion residues can also stick or cake on the rotary grate element 252, and in particular openings 256 (in 12a not shown) of the rotary grate element 252 clog, which worsens the combustion.

Figure 12b shows the rotary grate 25 in a second state, in which the rotary grate 25 with the rotary grate element 252 and the cleaning device 125 together with respect to the 12a have been further rotated in the direction of arrow D1.

In the course of rotating in the direction of arrow D<b>1 from the first state to the second state, the cleaning device 125 is moved integrally with the rotating grate member 252 . During this movement, the beating arm 124 is raised together with the mass element 127; the potential energy of the mass element 127 is increased.

The beating arm 124 remains in its starting angular position in the second state. The impact arm 124 has not yet moved relative to the rotary grate element 252 with the mass element 127 .

If the beater arm 124 is rotated further beyond this second state in the direction of arrow D1, which is shown in Figure 12c shown, into a third state, the impact arm 124 with the mass element 127 exceeds the fall start position F1, from which the impact arm 124 with the mass element 127 falls under the influence of gravitational acceleration onto a stop surface 128a of the rotary grate element 252, or from which the Impact arm 124 leaves its initial angular position relative to the rotary grate element 252 with the mass element 127 . In other words, the impact arm 124 tips over with the mass element 127 in the third state, covers the angular range η, and reaches a fall end position Fe or an end angle position, in which the mass element 127 hits the rotating grate element 252 . The at least one lancing element 129 penetrates the opening 256 with its projections first, and preferably penetrates the opening 256 completely. In other words, the piercing element 129 pierces through the opening 256 in such a way that its projections 130 pass completely through the rotary grate element 252 and the projections 130 protrude from the front side of the rotary grate element 252 in the third state.

Thus, the continued rotation of the rotary grate element 252 beyond the fall start position F1 initiates an acceleration movement of the mass element 127, in which the potential energy or potential energy of the mass element 127 is converted into kinetic energy. In addition, during this movement, when entering and also when penetrating the opening 256, the energy of the fall first serves to pierce (i.e. before the Striking is first stabbed), whereby a stabbing action resulting from the falling movement into the opening 256 concentrates on the removal of the ash and slag deposits in, on and at the opening 256. Furthermore, the stinging effect from the energy of the fall is advantageously concentrated on the tips or distal ends of the projections 256, since these hit the ash or slag deposits first with a relatively small impact area.

Due to the fact that the sinterings on and above the opening 256 in particular (as explained in more detail above with regard to the physics and chemistry of the sinterings) are flat and rather brittle, the projections 130 can break up these sinterings with the piercing effect more effectively than simply hitting the grate element 252 as is the case in the prior art.

In addition, the comb-shaped design of the projections 130 takes into account the slit-shaped or elongated design of the opening 256, so that the opening 256 can be cleaned completely. In this way, sinterings are removed over the entire length of the opening 256, which is also relevant because the opening 256 is clogged from the outside in and the middle of the openings 256 is therefore the last to be closed. In this respect, for example, a single projection 130 that would only be formed for the center of the opening 256 would possibly only pass through the (not yet) sintered center of the opening 256 and would not clean off the sintered edges of the opening 256 .

The fall start position F1 results from the usual laws of mechanics, taking into account the direction of action of the gravitational acceleration. The fall start position F1 can be determined, for example, by the relative position of the center of mass Ms (which is Figure 12b is only drawn in schematically for illustration purposes) relative to the position of the bearing 124 with its axis of rotation.

In Figure 12c a start of the (down) falling movement of the beating arm 124 from a fall start position F1 with the mass element 127 is shown in detail in dashed lines, and an end of the falling movement of the beating arm 124 with the mass element 127 is shown with shown in solid lines. At the end of the falling movement of the impact arm 124 with the mass element 127 , the mass element 127 hits the stop surface 128 a of the rotating grate element 252 . The fall start position generally represents a position of the mass element 127 and/or the impact arm 124 when the rotary grate 25 rotates, from which the fall movement begins.

The falling movement of the beating arm 124 with the mass element 127 is in principle a rotary movement. In terms of impulse physics, the impulse of the impact arm 124 with the mass element 127 when it hits the stop surface 128a is equal to the impulse sum of the distributed mass Σ mi ^∗ vi of the drop hammer, with the speed vi of the individual mass increments mi of the drop hammer depending on the radius of the rotary movement of the individual mass increments .

This impulse causes an impact or knocking on or against the rotary grate element 252 and also penetration or piercing (or depending on the length of the projections 130 also piercing or piercing) into the opening 256.

The impact or knocking causes the rotary grate element 252 to shake and, particularly in the case of a flexible coupling between the drive device and the bearing shaft 81, a rapid back and forth movement of the rotary grate element 252 about its axis of rotation. Combustion residues on the rotary grate element 252 are thus knocked off and also shaken off.

The impact or knocking of the mass element 127 on the stop surface 128a of the rotary grate element 252 results in a knocking effect with which the rotary grate element 252 can be cleaned of combustion residues, for example ash or slag.

Penetrating into the opening 256 also causes the ash or slag deposits and, in particular, planar sinterings to break up in, above and on the opening, since the tips of the projections 130 strike the deposits and sinterings in a targeted manner and break them.

With the penetration, it is ensured that flat sinterings are also broken up, which, for example, only occurred above the opening 256 but not in it. The investigations described above have shown that the sintering does not occur in the opening 256 or in its interior volume, but rather similar to the overgrowth of a layer of ice on a lake from its edges only at and above the opening 256, starting from the surface of the rotary grate element 252 .

The present cleaning device 125 thus combines two measures for grate cleaning: beating and piercing.

In Figure 12d a fourth state is shown, in which the rotating grate element 252 has rotated further in the direction of arrow D1. Here, the mass element 127 rests on the first stop surface 128a, and the second end 124b of the striking arm 124 does not rest on the stop surface 128.

The rotary movement in the direction of arrow D1 can now either stop at a predefined position and then continue in the opposite direction in the direction of arrow D2, or the rotary movement can be continued in the direction of arrow D1 until a 360 degree rotation has taken place. The rotary movement in the direction of arrow D2 can be continued in particular in such a way that the rotary grate element 252 returns to its working position 12a is moved back.

In both of the aforementioned cases of continuation of the rotational movement (further in the direction of arrow D1 or in the direction of arrow D2), a further fall start position can be reached in which the striking arm 124 moves to the starting position of the 12a or is moved back to its initial angular position. Here, the mass element 127 falls back, the second end of the striking arm 124b now striking the striking surface 128b with the striking arm head 126 there. The advantageous law of leverage applies here.

When the rotating grate element 252 (optionally) returns to its starting position, the mechanism explained above can be used to make a second impact or a second knock on the rotating grate element 252, which improves the cleaning of the rotating grate element 252.

Tests with an experimental installation have shown that the cleaning device 125 with the configuration explained above leads to a very efficient cleaning of the grate 25 and also the openings 256 of the grate 25 .

This efficient cleaning has the following reasons in particular:
The tapping or the impulse on the rotary grate element 252 occurs from the underside of the rotary grate element, which is opposite the contaminated or slagged combustion surface 258 . With this, most of the contamination or slag is knocked off the combustion surface 258 from the ideal direction, ie the combustion residues are knocked away from the grate 25 . This also applies to the penetration of the projections 130 into the openings 256 of the grate.

The tapping on the rotary grate element 252 also takes place directly on the rotary grate element 252 itself when the first tap is applied.

The mass element 127 can also have a considerable weight compared to the mass of the rotary grate element 252, for example 100 to 1000 grams. Due to the fall distance explained above and the gravitational acceleration, the resulting impulse is comparatively large, which means that in addition to the loose ash also more firmly adhering impurities or slag are removed can become. Due to the pointed ends of the projections 130, the impulse prior to tapping also concentrates on breaking up the ash or slag deposits and in particular the sintering at the openings 256.

With a back and forth rotation or a complete rotation of the rotating grate element 252, there is a two-time impact or tapping, with the result that the tapping effect is generated twice.

There are also other advantages:
The acceleration movement is initiated by rotating the rotary grate element 252, ie immanently at the point in time at which the grate is tilted for cleaning, but without requiring its own drive or a specially controlled triggering device. In this way, the knocking effect and the piercing effect are effected automatically at the right time due to the design.

The fall start position can advantageously be set in such a way that the combustion surface 258 points downwards when knocked, so that the combustion residues removed when knocked or knocked can fall directly into the ash container or chamber of the biomass heating system 1 .

In the following, with reference to the Figures 13a and 13b a second general example of the principle according to the invention of a cleaning device 125 for a rotary grate 25 is explained.

An acceleration movement of the mass element 127 can also be initiated without the Figures 12a to 12d The drop hammer configuration shown is done in a linear manner, explained as follows:
the 13a shows a rotary grate element 252 of a rotary grate 25 with a bearing axis 81 in a working position of the rotary grate element 252 or in a first state of the rotary grate element 252, as also in FIG 12a is shown. This is the working condition of the grate 25, where fuel rests on the combustion surface 258, is burned and combustion residues are produced. These combustion residues, such as ash or slag, lie on the grate 25 and can also adhere more firmly to the grate 25. In addition, combustion residues can also get into the perforation or the openings 256 of the grate and adhere to these openings 256, with the flow through the fuel bed 28 being impaired here.

Instead of the monkey's configuration of the 12a a suspension 122 for a mass element 127 with a corresponding counter bearing 133 or sliding bearing 133, for example a bushing 133, can now serve as a (linear) guide. In one case, the sliding bearings 133 can be guide openings 133 . For example, the suspension 122 can be in the form of a pin or rod with an end stop having a stop surface 128b. The mass element 127 can be movably provided on the suspension 122 in such a way that it can move back and forth in the longitudinal direction of the suspension 122 (cf. the double arrow P of the 13a , which also indicates a fall height for the mass element 127 when the rotating grate element 252 rotates; to the stop faces 127a, 127b of the mass element 127 cf Figures 12a and 12b ). For example, the mass element 127 can be in the form of a perforated disk, through the central hole of which the suspension 122 is passed (as a bushing or plain bearing). The mass member has a first surface 127a and a second surface 127b on both sides thereof. in the in 12a In the position shown, the second surface 127b of the mass element 127 rests on the end stop or the (second) stop surface 128b of the suspension 122 .

Furthermore, the mass element 127 can be designed as a plate 127, which is provided, for example, as a polygon or shaped body. The (surface) outline of the plate-shaped mass element 127 can be designed in such a way that it is adapted to the shape of the respective associated rotary grate element 252, 253, 254.

A plurality of lancing elements 129 can now be provided on this plate 127, with the lancing elements 129 being arranged in such a way that they can pierce or pierce their respectively opposite opening 256.

The mass element 127 as a plate 127 thus has the advantage that the piercing elements 127 can be provided to match openings 256 which are provided in a grate element 252, 253, 254 in a complex pattern. Such a complex pattern with a flow guidance-related distribution of the openings 256 (e.g. in different orientations and lengths) is shown in FIG 14 shown what is referred to. In this respect, the lancing elements 129 can be attached to the mass element 127 in such a way that the lancing elements 129 are provided complementary to the openings 256 . In other words, the tips of the projections 130 of the lancing elements 129 are the openings 256 in the first state 13a each across an air gap. When the rotating grate element 252, 253, 254 rotates, the piercing element 129 can penetrate linearly into the openings 256 or penetrate them.

This spacing of the piercing elements 129 from the openings in the first state or in the working position of the rotary grate 25 is advantageous since an undisturbed flow of air through the rotary grate 25 for combustion can be ensured (cf. the arrows LU in 13a ), although the piercing elements 129 are provided in close proximity to the opening.

The shape of the projections 130 also contributes to this. These taper in the direction of their distal end or taper to a point, with the result that only minimal disturbances in the air flow at the entrance into the opening 256 are generated at the lower entrance of the openings 256 .

When configuring the Figures 13a and 13b Furthermore, a largely undisturbed flow of the underside of the rotary grate 25 (which is advantageous for cooling the rotary grate 25 or the rotary grate elements 252, 253 and 254) is generally possible despite the presence of the cleaning device 125, since the mass element 127 and the piercing elements 129 are spaced apart are provided for rotary grate 25.

With the linear guide of the mass element 127, it can be further compared to the drop hammer configuration of the Figures 12a to d advantageously a lot of space or installation volume for the cleaning device 125 can be saved, which means that a cleaning device 125 can advantageously also be integrated in boiler 11 with a lower output (for example 50 kW) and with a correspondingly smaller rotating grate 25 .

Furthermore, a mass element 127, which is provided as a plate 127 under the respective rotary grate element 252, 25, 3, 254, can have a very considerable mass, with which the knocking and piercing effect can be improved.

Furthermore, two piercing elements 130 are provided on the mass element 127 for piercing or piercing into the openings 256 . In this view, the lancing elements 130 are only shown as individual projections 130 in a side view, but these can also extend in the form of a comb with a plurality of projections 130 (in Figures 13a and 13b e.g. perpendicular to the plane of the paper).

If the rotary grate element 252 is now rotated in the direction of arrow D1, as in FIG 13 is shown, the mass element 127 will slide or fall downwards on the suspension 122 when it reaches a fall start position (cf. the arrow ST in Fig Figure 13b ), and initially develop a piercing effect in the openings 256, and then (subsequently) strike with its first surface 127a on the (first) stop surface 128b. This can create a stabbing action and then a tapping action, just like that in relation to the Figures 12a to 12d is described.

If the rotary grate element 252 is subsequently rotated further either in the direction of the arrow D1 or in the direction of the arrow D2, then another fall start position can be reached, from which the mass element 127 slides back or falls, and with its second surface 127b onto the second stop surface 128b hits.

This can also with this second example of a cleaning device 125 of Figures 13a and 13b approximately the same advantages and effects can be achieved as in the first example Figures 12a to 12d .

(rotary grate 25 with rotary grate elements 252, 253, 254 and with cleaning devices 125)

the 14a shows a rotary grate 25 with three rotary grate elements 252, 253, 254 and with a plurality of cleaning devices 125 from a plan view of the rotary grate 25 in its working position or in the working state, which is referred to as the first state.

the Figure 14b shows the rotary grate 25 of 14 a with three rotating grate elements 252, 253, 254 and with respective cleaning devices 125 from a bottom view of the rotating grate 25.

the Figure 14c shows the rotary grate 25 of Figures 14a and 14b in a sectional view along the line A3-A3.

the Figures 14a to c show an implementation of the principle of Figures 13a and 13b .

The rotary grate 25 with the three rotary grate elements 252, 253, 254 and their function were above in relation to figures 8 and 9 described in more detail, which is why mainly the cleaning device 125 is explained below to avoid repetition.

the Figures 14a and 14b and 14c show the rotary grate 25 in the closed position or in a working position, with all rotary grate elements 252, 253 and 254 being aligned horizontally or closed. This is the position in normal operation. The rotary grate 25 has a base plate 251 and a transition element 255 from the base plate 251 to the rotary grate elements 252, 253, 254.

The direction or axis of insertion of the fuel onto the rotary grate 25 is indicated by the arrow E.

The motors 31 can drive the bearing axles 81 of the three rotary grate elements 252, 253, 254 via a rotary mechanism 23 in order to rotate them. The rotary mechanism 23, which is mounted in the rotary mechanism mount 22, couples the bearing axis 81 to the motors 31 via a toothed belt and gears, with the first and second rotary grate elements 252, 253 being rotated together, and the third rotary grate element 254 being rotated independently of the first and second rotary grate element 252, 253 can be rotated. Alternatively (not shown), however, all three rotary grate elements 252, 253, 254 can also be rotated independently of one another if, for example, three motors 231 are provided. The result of the rotation of the rotary grate elements 252, 253 and 254 is shown in FIGS figures 16 ff. are shown as an example of process steps for cleaning the rotary grate 25 .

they are in 14a and 14b two rotational position sensors 259 are shown, which can detect the rotational position of the bearing axles 81 . These rotational position sensors 259 can be magnetic-inductive sensors, for example. This serves to regulate the rotational position of the three rotary grate elements 252, 253, 254.

In the top view of 14a the rotary grate 25 is shown without a fuel bed with its three rotary grate elements 252, 253, 254, which have elongated or slit-shaped openings 256, which serve to supply air into the fuel bed from below.

The exemplary, relatively evenly distributed arrangement of the large number of openings 256 ensures a uniform flow through the fuel bed 28 (this is shown in 14a and 14b not shown) on the combustion surface 285 of the rotary grate 25 with primary air. This arrangement of the slit-shaped openings 256 , which is generally provided at an angle to the direction of insertion, prevents the formation of an air barrier when the pellets or wood chips are inserted, since these are significantly less likely to accumulate on the combustion surface 258 . For example, in the case of slot-shaped openings provided transversely to the direction of insertion, the probability is greater that the pellets or wood chips will stick to the catch the edges of the openings and fuel cannot be pushed through evenly. In the case of a grate 25, in particular with the above-described complex geometry of the rotary grate elements 252, 253, 254, with the partial angular arrangement of the slot-shaped openings 256, it is advantageously possible to provide an arrangement of the openings 256 with the most uniform possible distribution of the air flow through the fuel bed . However, this orientation of the openings 256, which is optimized in terms of flow technology and process technology, means that these also have to be cleaned off accordingly.

In addition, elongated or slit-shaped openings 256 have the advantage that they are easy to produce and that they have a significant opening area for the air flow, but without the fuel being able to fall through the grate. However, these openings 256 also have the disadvantage that these openings 256 can slag, which can interrupt the air supply to the fuel bed.

These slit-shaped openings 256 can preferably have a width of 4.6 mm +/- 0.5 mm (or + 0.4 mm and - 1 mm) and/or a length of 35 mm +/- 10 mm. The slit-shaped openings 256 can also have a width of 4.5 mm +/- 0.6 mm and/or a length of 40 mm +/- 20 mm.

Furthermore, some of the slot-shaped openings 256 also extend through the bearing axles 81 or the shafts 81, which also allows the primary air to flow into the fuel bed in the areas of the rotary grate elements 252, 253, 254 that are located above the shafts 81. Conversely, these openings 256, which extend through the shafts 81 and through the respective rotary grate element 252, 253, 254, have a significantly greater depth (and thus clog more easily) than the openings 256, which only extend through the respective rotary grate element 252 , 253, 254 extend.

In the openings 256 of 14a are visible from above, the distal ends of the lancing elements 129 and their projections 130 shown below the

Rotating grate elements 252, 253, 254 are arranged protruding in the direction of the openings 256.

In the Figure 14b , which shows the rotary grate 25 from below, nine cleaning devices 125 are also shown. The rotary grate elements 252, 253, 254 each have three cleaning devices 125, with which (preferably all) openings 256 can be cleaned by means of the piercing elements 129. Alternatively, two or four (or more) cleaning devices 125 can also be provided for each rotary grate element 252, 253, 254.

The nine cleaning devices 125 are provided on the underside of the rotary grate elements 252, 253, 254. The cleaning devices 125 have two suspensions 122 as part of (linear) guides and one movable ingot element 127x each. At least one piercing element 129 is attached to the mass element 127x, which protrudes from the mass element 127x in the direction of the rotating grate element 252, 253, 254.

The cleaning devices 125 with their mass element 127x are movably attached to the respective rotating grate elements 252, 253, 254 by means of the suspension 122. The suspensions 122 enable a substantially linear or rectilinear movement of the mass elements 127x away from the rotary grate element 252, 253, 254 and towards it. In other words, the mass elements 127x are suspended or guided in such a way that they perform a translational movement when the rotary grate element 252, 253, 254 rotates.

The suspensions 122 are in the working position Figures 14a , 14b and 14c downwards and store the mass elements 127x. The mass elements 127x are preferably mounted or guided exclusively by the suspensions 122 . The suspensions 122 are designed as linear suspensions in the form of rods or pins and are attached to the rotating grate element 252 , 253 , 254 or to the bearing axis 81 . The suspensions 122 can be designed as round rods or as guide bolts 122 .

The present linear suspension serves as a linear bearing with relatively low friction and a guide that is as free of play as possible. The length of the suspensions 122 defines the length of the stroke of the mass element 127x when the rotary grate element 252, 253, 254 rotates, which in turn defines the impact and piercing energy of the cleaning device 125.

For the suspension 122, complementary sliding bearings or bushings 133 are provided in the mass elements 127x. These bushings 133 or plain bearings 133 can be referred to somewhat more generally as guide openings 133 .

Guide openings 133 are thus provided in the mass elements 127x as plain bearings 133 for receiving the rod-shaped suspensions 122 or for receiving the guide bolts 122 . The guide openings 133 are preferably deburred and smoothed on the inside, for example polished. Likewise, the guide openings 133 can be produced by means of laser cutting, which means that they have a good surface quality and fitting accuracy.

In the present case, two suspensions 122 with two complementary guide openings 133 are provided in the mass elements 127x, whereby a linear carriage guide is provided for a movable carriage in the form of the mass element 127x.

This type of linear guide has the considerable advantage that it requires very little space and is very compact but at the same time efficient (especially compared to the drop hammer variant of a cleaning device 125). Due to the construction, the cleaning device can have sufficient fall energy of the mass element 127x, whereby this is largely dependent on the friction of the linear guide, the mass of the mass element 127x and the fall height of the mass element 127x=length of the guide. However, these parameters can also be realized with the present compact cleaning device 125 with a reliable linear guide with sufficient falling energy for the even cleaning of the grate 25 .

Due to the significantly smaller space requirement of the present cleaning devices 125, it is only possible to integrate such a cleaning device 125 in a boiler 11 of smaller design (or with lower capacity), and also to have several cleaning devices 125 (e.g. 3) under one Attach rotary grate element 252, 253, 254 to provide a more even cleaning with knocking and piercing action.

In addition, the mass element 127x tilts or jams much less with a carriage guide, since the guide can be equipped with a relatively large amount of play, and it nevertheless has a clearly defined range of movement. In other words, a large mass, such as that of the mass element 127x, can be reliably movably supported with a linear slide guide without the usual soot, dust or slag deposits leading to guide failure.

Furthermore, the guide must be designed in such a way that the piercing elements 129 can pierce or pierce the openings 256 . In this case, it is necessary for a plurality of elongate or plate-shaped lancing elements 129 to be aligned and guided in such a way that they are introduced into the openings 256 and/or guided through the openings 256 together with the movement of the mass element 127x. In other words, the lancing elements 129 moved with the mass element 127x must be provided with an exact fit for the respective corresponding openings 256 in order to prevent the lancing elements 129 from tilting or wedging in the openings 256 .

A reliable linear guide is provided for this purpose.

In addition, it is preferred that piercing elements 129 are located in the openings 256 in every position of the mass element 127x, so that, on the one hand, no foreign bodies can accumulate on the underside of the grate 25 in front of the openings 256 (which prevent the piercing element 129 from entering the opening 256 from could prevent the underside) and thus, on the other hand, the position of the lancing elements 129 in the

Openings experience a further guidance of the mass element 127x with its piercing elements 129 in relation to the rotating grate element 252, 253, 254. In other words, the movement of the mass element 127x with its pricking elements 129 can be defined not only by the linear guide, but also by the pricking elements 129 in the respective openings 256.

In this regard, it should be remembered that the investigations described above into the ash or slag deposits have shown that these largely arise on the upper side of the grate 25 and the openings 256 clog from the outside due to the build-up of a layered structure. In this respect, it is not necessary for the piercing elements 129 to pierce or push into the openings 256 from below (i.e. through the lower opening level of the openings 256, which is formed by the underside of the rotating grate elements 252, 253, 254).

Rather, for cleaning the grate 25 and the openings 256, it is sufficient for the piercing elements 129 to be moved through only part of the openings 256 and for the piercing elements 129 to pierce the openings 256 on the upper side with their projections 130, i.e. for the piercing elements 129 during cleaning or the falling movement of the mass element 127x through the upper opening level of the openings 256 (which is formed by the upper side of the rotating grate elements 252, 253, 254.

The resistance of any existing (stubborn) slag or ash deposits is efficiently overcome, with the pointed projections 130 of the piercing elements 129 exerting a piercing effect in the form of breaking up the ash or slag deposits.

The projections 130 of the lancing elements 129 are preferably designed in the form of a comb or a fork. In this respect, a lancing element 129 has a plurality of projections 130 which are arranged one after the other in one plane. An opening 256 can thus be cleaned over its entire length, since the slag or ash deposits are broken up at several points. However, it unfolds the puncturing effect of puncturing elements 129 with projections 130 arranged in the form of a comb is nevertheless selective, as a result of which the falling energy can also act selectively in the areal slag or ash deposits. This also breaks up very stubborn or solid deposits of slag or ash. After the (preferably pointed) projections 130 hit the slag or ash deposits, the projections push further through the slag or ash deposits. It is advantageous that the projections 130 taper continuously in the direction of their distal ends (in at least one sectional plane of the projection 130) (cf. Figure 14c , centre), or steadily expand in the direction of their proximal ends, so that "wedges" are driven into the slag or ash deposits, which may further break away and break up any slag or ash deposits remaining at the opening 256 after impact will.

In addition, the projections 130 do not disadvantageously impede the supply of air into the openings 256, although the projections 130 are already partly in the openings 256 in their initial position (i.e. in the working position of the rotating grate elements 252, 253, 254) (as also in FIG Figure 14c you can see).

The mass elements 127x of Figure 14b are adapted in their shape to the shape of the respective rotary grate elements 252, 253, 254 in such a way that mass elements 127x do not protrude beyond the surface of the respective rotary grate element 252, 253, 254 when they rest on the rotary grate element.

In the 14a , 14b and 14c the mass members 127 hang down to their original position, and the mass members 127 are spaced from the rotating grate members 252,253,254. When rotating one or more rotary grate elements 252, 253, 254, the rotary grate elements 252, 253, 254 are cleaned by the respective cleaning device 125, as in principle with respect to Figures 13a and 13b is explained, and how this is explained below in detail with reference to the following figures 16 ff. is explained.

• Jedes Drehrostelement 252, 253, 254 ist mittels einer Welle 81 bzw. Lagerachse 81 drehbar gelagert. Hieraus ergibt sich, dass unter dem Drehrostelement 252, 253, 254 (regelmäßig mittig) die Welle 81 vorgesehen ist, welche die Reinigungseinrichtung 125 von dem Drehrostelement 252, 253, 254 beabstandet angeordnet und mithin die Reinigungswirkung des Abklopfens verschlechtert. Es führt die Lagerung des Drehrostelements 252, 253, 254 mittels einer Welle 81 generell dazu, dass eine Klopfwirkung der Reinigungseinrichtung verschlechtert wird, da diese die Aufschlagenergie des Klopfens teilweise aufnimmt und mithin dämpft. Insofern landet ein guter Teil der Aufschlagenergie in der Welle 81 und nicht im Drehrostelement 252, 253, 254, was nachteilhaft ist. Wie Versuche gezeigt haben, ist somit eine einzelne Reinigungseinrichtung 125 auf einer Welle nicht so effektiv bei der Abreinigung des gesamten Drehrosts 25 incl. dessen Öffnungen 256, wie diese sein sollte (vgl. Ausführungen zur Fig. 22). Dieser Umstand verstärkt sich dann auch noch besonders bei diversen Brennstoffen, welche stärker zur Versinterung neigen, wie erläutert.

The special concept shown here of three cleaning devices 125 per rotary grate element 252, 253, 254 (or at least two cleaning devices per rotary grate element) is based on the following additional considerations:

• Each rotary grate element 252, 253, 254 is rotatably mounted by means of a shaft 81 or bearing axis 81. This results in the shaft 81 being provided below the rotary grate element 252, 253, 254 (usually in the middle), which arranges the cleaning device 125 at a distance from the rotary grate element 252, 253, 254 and thus impairs the cleaning effect of the tapping. The mounting of the rotating grate element 252, 253, 254 by means of a shaft 81 generally results in the knocking effect of the cleaning device being impaired, since this partially absorbs the impact energy of the knocking and consequently dampens it. In this respect, a good part of the impact energy ends up in the shaft 81 and not in the rotary grate element 252, 253, 254, which is disadvantageous. As tests have shown, a single cleaning device 125 on a shaft is not as effective in cleaning the entire rotating grate 25, including its openings 256, as it should be (cf. comments on 22 ). This circumstance is then also amplified, especially with various fuels, which tend to sinter more strongly, as explained.

However, if three cleaning devices 125 are provided, one cleaning device 125 can be provided on the left and one on the right of the shaft 81, and a cleaning device 125 can be provided on the shaft 81 or on the bearing axis 81. In this way, the cleaning devices 125 to the left and right of the shaft 81 hit the rotating grate element 252, 253, 254 directly (without the shaft 81 in between) in the event of impact on the latter, which means that the knocking effect can have a direct effect on the rotating grate element 252, 253, 254 . The cleaning device 125, which is arranged above or adjacent to the shaft 81 or the bearing axis 81, is also provided specifically for cleaning the central area of the rotary grate element 252, 253, 254, whereby its impact energy is only provided for this area. Thus, the different areas of the rotary grate element 252, 253, 254 can be applied separately with the impact energy, with which the problem of "Incomplete" cleaning of conventional rotary grates is remedied with conventional cleaning equipment.

The present concept of a cleaning device 125 can also be flexibly adapted to different and/or complex grate shapes. The cleaning device 125 can also be used at precisely that point or surface of the grate 25 at which the greatest accumulation of contamination can be expected. In other words, the cleaning device can advantageously be set up in such a way that the knocking effect is generated directly at the points of the grate 25 to be cleaned and that the piercing effect also covers (preferably all) openings 256 of the grate 25 .

In summary, in the present cleaning device 125, the piercing elements 129 with their linear guide ensure reliable cleaning of the openings 256, while at the same time the form and arrangement of the plurality of cleaning devices 215 also improves the knocking-off effect and at the same time the space required for such a cleaning device 125 is lower. than with conventional cleaning devices. In other words, the present cleaning device 125 combined a tapping and a stabbing cleaning means for a grate 25 in a single compact and effective mechanism.

the Figures 15a to 15o show views of parts of the cleaning devices 125 of FIG Figures 14a to 14c . Here is in the Figures 15a to 15o a set of mass elements 127x with their piercing elements 129 for the nine cleaning devices 125 of Figures 14a to 14c shown. In each case, three figures ( Figures 15a, 15b and 15c , such as Figures 15d, 15e, 15f , such as Figures 15g, 15h and 15i , such as Figures 15j, 15k and 15l , such as Figures 15m, 15n and 15o ) a mass element 127x with its lancing elements 129 from three different views, specifically in a side view, in a plan view and in a three-dimensional oblique view. The terms "top" and "bottom" refer to the position of the features shown in the working position of the rotary grate 25, ie, the Rotating grate elements 252, 253, 254 are not rotated or tilted. The terms “proximal” and “distal” relate to the lancing elements 129 and their position relative to the mass element 127x, which is regarded as the starting body.

In the Figures 15a to 15o For the sake of clarity, not all reference symbols and notes have been shown repeatedly. However, elements or features that look the same in the figures are also to be understood with the same reference symbols.

What they have in common Figures 15a to 15o that these mass elements 127x have pricking elements 129 provided corresponding to the corresponding openings 256 . The lancing elements 129 are also adapted to the respective extension direction of the respective corresponding openings 256, for example rotated.

The mass elements 127x consist (preferably) of stacked metal plates, which can be laser cut. In this case, the lowermost and the uppermost plate of the mass elements 127 can have a different outline.

The mass elements 127x are each provided with two plain bearings 133 for receiving the suspensions 122 . Recesses 134 are provided in the slide bearings 133 in such a way that they enlarge the space in the slide bearing 133 in the middle. The recesses 134 are preferably provided open to the outside of the mass element 127x, so that ash and slag, which is introduced into the plain bearing 133, for example when the mass element 127x moves, can leave the plain bearing 133 again without complications.

The recesses 134 in the respective mass elements 127x also serve to further minimize the so-called "drawer effect" in the present linear carriage guide. The drawer effect refers to the mechanical jamming of a carriage on a guideway as a result of tilting. It is triggered by a torque acting on the carriage, which means there is a risk of self-locking.

In order to make the present (sliding) guides as smooth-running as possible, the greatest possible guide play is sought with the recesses 134 . As a result, the outer edges or the end areas of the plain bearings 133 or bushings 133 or guide openings 133 touch the guide track, whereby the guide length is maximized. In addition, the guide with the recesses 134 is more tolerant of shape errors such as unevenness or changes in shape due to stress-related or thermally-related deflection. Likewise, the contact surface for the sliding of the suspension 122 in the plain bearings 133 is reduced, which generally reduces friction. In addition, through the recess 134, slag, ash, foreign bodies in the fuel (e.g. metal residues in pellets) can escape more easily from the sliding bearing 133 or be carried out by the movement. In this respect, the recesses 134 optimize the function of the present linear guide.

Furthermore, the mass elements 127x are adapted to the shape of the respective rotary grate elements 252, 253, 254 in terms of their shape or their outer contours in a plan view (i.e. viewed from above or below). The mass elements 127x are shaped in such a way that they can be arranged next to one another under the respective rotating grate element 252, 253, 254 without interfering with one another and without protruding beyond the outline of the respective rotating grate element 252, 253, 254. However, the mass elements 127x are of such a flat design that all the openings 256 of the grate 25 can be "reached" or pierced by the piercing elements 129 . In other words, the available area under the respective rotary grate element 252, 253, 254 is optimally utilized in order to be able to accommodate a large amount of mass (for a good cleaning effect) on the one hand and to close all or at least many openings 256 of the rotary grate with the piercing elements 129 on the other achieve, while the entire structure is still space-saving and compact.

The approximately elongate (and preferably plate-shaped) lancing elements 129 also have three sections: at one (proximal) end, a fastening part 131 for fastening the lancing element 129 to the mass element 127x (whereby the fastening part 31 is fully inserted in the mass element 127x in the present case), on which other (distal) end the tapered projections 130, and between the Fastening part 131 and the projections 130 is a middle part 132. The transition between the projections 130 and the middle part 132 is roughly indicated by the dotted line.

the Figures 16 to 21 show the grate 25 of the Figures 14a , 14b and 14c successively in the execution of an exemplary step-by-step and / or complete cleaning process or method, the first state as the initial state in the Figures 14a , 14b and 14c is shown.

In order to avoid repetition, the features and the function of the cleaning devices 25 are related to the explanations of the 14a , 14b and 14c referred. Likewise, for reasons of clarity in the Figures 16 to 21 not all references of the 14a , 14b and 14c shown repeatedly. However, the corresponding characteristics are identical. The sections A3-A3 refer to the cutting lines of the figures 14 .

From the in the Figures 15a to 21 illustrated method steps, however, only individual steps can be carried out. For example, only a partial cleaning of a single rotary grate element 252, 253, 254 can be carried out, what the Figures 14 to 17 is equivalent to. In general, each rotating grate element 252, 253, 254 can be rotated individually and thus cleaned individually. Also, for example, all rotary grate elements 252, 253, 254 could be rotated simultaneously if, for example, no rotary grate lips or no mutual rotation limitations are present. In addition, a rotary grate element 252, 253, 254 can be rotated fully by 360 degrees, or a rotary grate element 252, 253, 254 can be rotated back and forth, for example by only up to 180 degrees. Alternatively, the grate 25 can also have only one rotary grate element or only two rotary grate elements.

16 shows a vertical cross-sectional view of the grate 25 of FIG 14a in a second state.

For example, after a predetermined burning time has elapsed and/or after a fire bed height sensor (not shown) has detected a predetermined ash height (and thus quantity), a system controller (not shown) determines that partial or full cleaning of the grate 25 should take place. In the present case, the system control determines that the grate 25 should be completely cleaned in stages.

In this second state, the third rotating grate element 254 has been rotated in the direction of arrow D1. The mass element 127 of the cleaning device 125 of the third rotary grate element 254 is raised with the force of one of the motors 231 of the rotary mechanism 23, with its potential energy being increased. The other rotating grate elements 252, 253 remain in the starting position. The rotary grate element that is at the furthest distance from the fuel insert E is thus rotated first. In this state, the loose ash falls down from the third rotary grate element 254 for ash discharge. However, ash or slag can still adhere to the third rotary grate element 254 .

17 shows a vertical cross-sectional view of the grate 14a in a third state.

In this third state, the third rotary grate element 254 has been rotated even further in the direction of arrow D1. The combustion surface 258 of the third rotary grate element 254 now overhangs, with the result that the loose or detached ash can fall off the rotary grate element 254 even better. However, ash or slag can still adhere to the third rotary grate element 254 . The purpose of the cleaning device 125 according to the invention is to remove precisely these combustion residues from the grate 25, which are more difficult to remove.

In 17 the arrow ST indicates the movement of the falling and the distance of this falling of the mass elements 1271, 274 of the rotary grate element 254. It can be seen that the piercing elements 129 have passed through the openings 256 and thus clean these openings 256 of ash and slag deposits. The lancing elements 129 with their projections 130 are designed in such a way that the projections 130 have also passed completely through the openings 130 and that consequently the central part 132 of the lancing elements 129 is located in the openings. In other words, the lancing element passes through the upper opening surface of the respective opening 256 with its middle part 132 as it falls.

This ensures that the openings 256 are cleaned at least over the cross-sectional area of the central part 132, which advantageously opens up the majority of the opening cross-section of the openings 256.

• Beim Herabfallen stoßen ersichtlich zuerst die Spitzen der Vorsprünge 130 durch die Öffnungen 256, womit die Fallenergie zuerst sehr punktuell auf die Asche- bzw. Schlackedepositionen über und in den Öffnungen 256 wirkt. Dabei erfolgt ein erstes Aufbrechen auch recht harter Verschlackungen oder Versinterungen.

Furthermore, the configuration of the lancing element 129 explained above also leads to a temporally advantageous sequence of the cleaning effects of the present cleaning devices 125:

• As can be seen, when falling, the tips of the projections 130 first push through the openings 256, with the result that the falling energy first acts very selectively on the ash or slag deposits above and in the openings 256. In the process, even quite hard slagging or sintering is broken up for the first time.

Thereafter, the projections 130 penetrate further into the ash or slag deposits and blast them further onto or away from the grate 25 .

Thereafter again, the center portion 132 enters the opening 256 and passes through the opening 256, removing any remaining ash or slag from the openings 256.

Due to the length of the lancing element 129 (cf. 17 , this protrudes from the rotary grate element 254), the fall of the mass element 127x can now continue even after piercing the openings 256, whereby the mass element 127x again hits the rotary grate element 254 with a sufficient impulse with its surface 127b and thus develops an effective knocking-off effect can. With this geometry, it is avoided that the mass element 127x is permanently decelerated when piercing into the openings 256 in such a way that there is not sufficient momentum for knocking off the rotating grate element 254 afterwards.

In order to achieve the effect described above, the length of the projections 130 can preferably be at least the thickness of the rotary grate element 254 . Additionally, the length of the central portion 132 may be at least twice the thickness of the rotary grate member 254 .

18 shows a vertical cross-sectional view of the grate 14a in a fourth state.

In this fourth state, the third rotating grate element 254 has been rotated even further in the direction of arrow D1. By tipping over the rotary grate element 254 further, gravity is used so that ash or slag that is still slightly adhering (this can also be electrostatically charged, for example) falls down into the funnel-shaped ash container 74 .

19 shows a vertical cross-sectional view of the grate 14a in a fifth state.

In this fifth state, the first and second rotating grate elements 252, 253 have been rotated together in the direction of arrow D3. The direction of rotation is the opposite of the direction of rotation D1. In the process, the mass elements 127x of the cleaning devices 25 of the first and second rotary grate elements 252, 253 are further raised. The third rotary grate element 254 remains in a stationary rotary position.

In this sixth state, the first and second rotary grate elements 252, 253 have been rotated further together in the direction of arrow D3. The mass elements 127 have exceeded their fall start positions and have fallen onto the stop surfaces 128a of the first and second rotary grate elements 252, 253, respectively, and have punctured and knocked off the rotary grate elements 252, 253. The third rotary grate element 254 remains in a stationary rotary position. The mass elements 127x have thus fallen down and the piercing elements 129 have passed through the openings 256 . The third rotary grate element 254 remains in a stationary rotary position.

21 shows a vertical cross-sectional view of the grate 14a in a seventh state.

In this seventh state, the first and second rotary grate elements 252, 253 have been rotated further together in the direction of arrow D3. This allows the ash or slag to fall more easily.

After the seventh state, the rotating grate elements 252, 253, 254 can be rotated back into their working positions. A cleaning by tapping and piercing the openings 256 has taken place. The cleaning process can thus return to the first state.

(Further embodiments)

In addition to the explained embodiments and aspects, the invention permits further design principles. Thus, individual features of the various embodiments and aspects can also be combined with one another as desired, as long as this is apparent to the person skilled in the art.

The rotary grate 25 of Figures 9 to 11 is shown without the cleaning device 125, but can be combined at any time with one of the cleaning devices 125 shown in the following figures.

Although the cleaning facility in the Figures 9 to 11 is not shown, that can be related to the Figures 12a to 21 Also explained on the rotary grate 25 of the Figures 9 to 11 Find application, with an improved cleaning of the rotary grate 25 can be achieved in particular in the partial and universal cleaning. This allows the technical teaching on the cleaning device 125 with the technical teaching on the Figures 9 to 11 be combined in a way that makes sense to those skilled in the art.

The rotary grate 25 is described here as an example with three rotary grate elements 252, 253, 254. However, the rotary grate 25 can also have only one rotary grate element 252, or also two rotary grate elements 252, 253. In principle, a rotary grate 25 with a plurality of rotary grate elements is conceivable. In this respect, the present disclosure is not limited to a specific number of rotary grate elements 252, 253, 254.

Furthermore, each rotary grate element 252, 253, 254 can have two or more cleaning devices 125. Likewise, a rotary grate element or several rotary grate elements from the total number of rotary grate elements of the rotary grate 25 can also have no cleaning device 125 . For example, only one of the rotary grate elements 252, 253, 254 can have at least two cleaning devices 125.

Instead of three cleaning devices 125, two or four, and therefore at least two, cleaning devices 125 can also be provided for each rotating grate element 252, 253, 254. At least one piercing element 129 can be provided for each cleaning device 125 . A lancing element 129 does not necessarily have to be provided for each opening 256 . Fewer lancing elements 129 than openings 256 can also be provided. Furthermore, more than two guides or suspensions 122 with plain bearings 133 can also be provided per cleaning device 125, as long as these enable a linear movement of the respective mass element 127x.

The recirculation device 5 is described here with a primary recirculation and a secondary recirculation. However, in its basic configuration, the recirculation device 5 can also only have a primary recirculation and no secondary recirculation. With this basic configuration of the recirculation device, the components required for the secondary recirculation can be omitted completely, for example the recirculation inlet channel divider 532, the secondary recirculation channel 57 and an associated secondary mixing unit 5b, which will be explained, and the recirculation nozzles 291 can be omitted.

Alternatively, only one primary recirculation can be provided in such a way that the secondary mixing unit 5b and the associated channels are omitted, and the mixture of the primary recirculation is not only fed under the rotary grate 25, but also (e.g. via another channel) to the is supplied to the recirculation nozzles 291 provided in this variant. This variant is mechanically simpler and therefore less expensive, but still has the recirculation nozzles 291 for creating a swirl in the flow in the combustion chamber 24 .

An air quantity sensor, a vacuum unit, a temperature sensor, an exhaust gas sensor and/or a lambda sensor can be provided at the inlet of the flue gas recirculation device 5 .

Furthermore, instead of only three rotary grate elements 252, 253 and 254, two, four or more rotary grate elements can also be provided. For example, five rotary grate elements could be arranged with the same symmetry and functionality as the three rotary grate elements presented. In addition, the rotary grate elements can also be shaped or designed differently from one another. More rotary grate elements have the advantage that the crushing function is increased.

With regard to the specified dimensions, it should be noted that other dimensions or combinations of dimensions can also be provided that deviate from these.

Instead of the convex sides of the rotary grate elements 252 and 254, concave sides of these can also be provided, in which case the sides of the rotary grate element 253 can be shaped in a complementary convex manner. This is functionally almost equivalent.

Fuels other than wood chips or pellets can also be used as fuels in the biomass heating system.

Alternatively, the rotary grate can also be referred to as a tipping grate.

The biomass heating system disclosed here can also be fired exclusively with one type of fuel, for example only with pellets.

The combustion chamber blocks 29 can also be provided without the recirculation nozzles 291 . This can apply in particular to the case in which no secondary recirculation is provided.

The geometry, in particular of the circumference of the rotating grate elements 252, 253, 254, can vary from that in 14a geometry shown. Thus, the doctrine relating to the angular arrangement of the slot-shaped openings 256 of 14a can also be applied to other types and shapes of gratings. In addition, tilting or sliding grates with the angled arrangement of the slot-shaped openings 256 can also be provided, for example.

The embodiments disclosed herein were provided for description and understanding of the disclosed technical matters and are not intended to limit the scope of the present disclosure. Therefore, it is to be construed that the scope of the present disclosure includes any modification or other various embodiments based on the technical spirit of the present disclosure.

(Reference List)

1

Biomass heating system

11

boiler

12

boiler foot

13

boiler housing

14

water circulation device

15

fan

16

outer lining

125

cleaning device

121

Attachment with stop

122

suspension

123

Axis of rotation/bearing/joint

124

hitting arm

124a, 124b

first end, second end of the hitting arm

126

beater head

127

mass element

127x

Mass elements (x= 1 to 5)

127a, 127b

area of the mass element

128a, 128b

stop surface

129

piercing element

130

protrusions of the lancing element

131

Fastening part of the lancing element

132

Middle part of the piercing element

133

Plain bearing or bushing of the guide

134

Recess in the mass element

2

burner

21

first maintenance opening for the burner

22

rotary mechanism mount

23

turning mechanism

24

combustion chamber

25

rotary grate

26

Primary combustion zone of the combustor

27

Secondary combustion zone or radiant part of the combustion chamber

28

fuel bed

29

combustion chamber bricks

A1

first horizontal cutting line

A2

first vertical cutting line

201

ignition device

202

combustion chamber slope

203

combustor nozzle

211

Insulation material e.g. vermiculite

231

Drive or motor(s) of the turning mechanism

251

bottom plate of the rotary grate

252

First rotary grate element

253

Second rotary grate element

254

Third rotary grate element

255

transition element

256

openings

257

rust lips

258

burn surface

259

rotation sensor

260

Support surfaces of the combustion chamber bricks

261

groove

262

head Start

263

ring

264

bracket stones

265

slope of the support stones

291

Secondary air or recirculation nozzles

298

Areas with a poorer cleaning effect

299

Places with good cleaning effect

3

heat exchanger

31

Maintenance opening for heat exchanger

32

boiler tubes

33

Boiler tube entry

34

reversing chamber entry

35

turning chamber

36

spring turbulator

37

Band or spiral turbulator

38

heat exchange medium

331

Insulation at the boiler tube inlet

4

filter device

41

exhaust outlet

42

electrode supply line

43

electrode holder

44

filter inlet

45

electrode

46

electrode insulation

47

filter outlet

48

Cage

49

flue gas condenser

411

Flue gas supply line to the flue gas condenser

412

Flue gas outlet from the flue gas condenser

481

cage mount

491

first fluid connection

491

second fluid port

493

heat exchanger tube

4931

pipe holding element

4932

tube sheet element

4933

loops/reversals

4934

first spaces between the heat exchanger tubes

4935

second spaces of the heat exchanger tubes to the outer wall of the flue gas condenser

4936

culverts

495

header element

4951

header flow guide

496

condensate outlet

4961

condensate collection funnel

497

flange

498

Side surface with maintenance opening

499

Mounting device for the flue gas condenser

5

recirculation device

50

Ring channel around combustion chamber bricks

52

air valve

53

recirculation entry

54

primary mixing channel

55

Secondary mixing channel or secondary tempering channel

56

primary recirculation channel

57

secondary recirculation channel

58

primary air duct

59

secondary air duct

5a

primary mixing unit

5b

secondary mixing unit

521

valve actuator

522

valve positioning axes

523

valve vane

524

valve body

525

valve antechamber

526

valve passage opening

527

valve body

528

valve face

531

recirculation entry channel

532

recirculation entry channel splitter

541

primary passage

542

primary mixing chamber

543

primary mixing chamber outlet

544

primary reciprocating valve entry

545

Primary air valve inlet

546

Primary mixing chamber housing

551

secondary passage

552

secondary mixing chamber

553

secondary mixing chamber outlet

554

secondary reciprocating valve entry

555

secondary air valve inlet

556

secondary mixing chamber housing
581 primary air inlet
582 primary air sensor
591 secondary air intake
592 secondary air sensor
6 fuel supply
61 rotary valve
62 axis of fuel supply
63 translation mechanics
64 fuel supply channel
65 fuel supply opening
66 drive motor
67 Fuel Auger
7 ash removal
71 Ash discharge screw
711 worm axis
712 centering disc
713 heat exchanger section
714 burner section
72 ash removal motor with mechanics
73 transitional snail
731 right subsection—snail rising to the left
732 left subsection - snail rising to the right
74 ash container / ash tray
75 Transition snail shell
751 Opening of the transitional snail housing
752 boundary plate
753 Main body section of the housing
754 fastener and separator
755 funnel element
81 bearing axles
82 Axis of rotation of the fuel level flap
83 fuel level flap
831 main face
832 center axis of the axis of rotation or bearing shaft 81
833 surface parallels
834 openings
84 bearing notch
85 sensor flange
86 ember bed height measuring mechanism
9 cleaning device
91 cleaning drive
92 cleaning waves
93 shaft mount
94 extension
95 turbulator mounts
951 pivot bearing mount
952 processes
953 culverts
954 recesses
955 pivot linkage
96 two-armed hammer
97 stop head
E Insertion direction of the fuel
S ^∗ flow arrows
F1 fall start position
D1 first direction of rotation
D2,D3 second directions of rotation, which are opposite to the first direction of rotation
H horizontal
FS clout
Ms center of mass
S (ST) direction of descent
Le longitudinal axis of the slots
ST fall vector of mass element 127x

Claims (17)

Revolving grate (25) for a biomass heating system (1), having at least one rotary grate element (252, 253, 254) with a perforation of a plurality of slot-shaped openings (256); at least one bearing axle (81) by means of which the rotary grate element (252, 253, 254) is rotatably mounted; at least one cleaning device (125) attached to one of the rotary grate elements (252, 253, 254), the cleaning device (125) having a mass element (127x) that is movable relative to the rotary grate element (252, 253, 254) and lancing elements attached to the mass element (127x). (129) for the openings (256); wherein the cleaning device (125) is set up in such a way that when the rotary grate element (252, 253, 254) rotates, an acceleration movement of the mass element (127x) is initiated, so that the cleaning device (125) has a knocking effect on the rotary grate element (252, 253, 254 ) and exerts a piercing effect on the openings (256) in order to clean the rotary grate element (252, 253, 254) with its openings (256). Rotary grate (25) for a biomass heating system (1) according to claim 1, wherein the cleaning device (125) is set up in such a way that the mass element (127x) is lifted to a fall start position (F1) when the rotating grate element (252, 253, 254) rotates to initiate the acceleration movement, from which the mass element (127x) is moved under the influence of gravitational acceleration by means of a linear guide (122, 133) falls linearly to the To generate a knocking effect on the rotary grate element (252, 253, 254) and at the same time the piercing effect for the openings (256). Rotary grate (25) for a biomass heating system (1) according to claim 1 or 2, wherein
a height of fall for the falling of the mass element (127x) and a mass of the mass element (127x) are set up in such a way that as it falls, ash deposits on and in the openings (256) caused by sintering can be removed by the piercing effect. Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
the linear guide (122, 133) is designed as a linear slide guide with two suspensions (122) and two complementary guide openings (133). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
the lancing elements (129) are comb-shaped with a plurality of projections (130). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein the lancing elements (129) have a length such that they can completely penetrate the openings (256), and the lancing elements (129) are designed with projections (130) in such a way that the projections (130) taper continuously in the direction of their distal ends; and the lancing elements (129) are arranged in such a way that they are each provided complementary to the openings (256). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein the lancing elements (129) are plate-shaped, and the lancing elements (129) have a fastening part (131) for fastening to the mass element (127x), and the lancing elements (129) have a plurality of projections (130) tapering in the longitudinal direction of the lancing element (12), and the piercing elements (129) have a central part (132) between the fastening part (132) and the projections (130). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
a length of the central part being dimensioned in such a way that it can completely penetrate the rotary grate element (252, 253, 254). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
the mass element (127x) has slot-shaped recesses in which the lancing elements (129) for fastening the lancing elements (127x) to the mass element (127x) are accommodated. Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
the mass element (127x), to which the piercing elements (129) are attached, is set up in such a way that a piercing element (129) is provided for each opening (256) of the rotating grate element (252, 253, 254). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein the cleaning device (125) comprises: a suspension (122) attached to the rotating grate element (252, 253, 254) and plain bearings (133) in the mass elements (127x), which together form a linear carriage guide which enables a linear movement of the mass element (127x) to the rotating grate element (252, 253, 254) and made possible from there. Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
at least three cleaning devices (125) are provided for one rotary grate element (252, 253, 254), one cleaning device being provided on a bearing axis (81) of the rotary grate element (252, 253, 254), and the other cleaning devices (125) each being adjacent to one another are provided. Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein the mass element (127x) has sliding bearings (133) as the guide openings (133) for receiving the suspension (122). the mass element (127x) has two outer plates between which a plurality of inner plates are sandwiched, the inner plates having recesses (134) which extend up to the plain bearing (133). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
the cleaning device (125) is attached to the underside of the rotating grate element (252, 253, 254) opposite a combustion surface (258) of the rotating grate element (252, 253, 254). Rotary grate (25) for a biomass heating system (1) according to any one of the preceding claims, wherein
the rotary grate (25) has a first rotary grate element (252), a second rotary grate element (253) and a third rotary grate element (254), which are each arranged to be rotatable by at least 90 degrees about the respective bearing axis (81). Method for cleaning a rotary grate (25) of a biomass heating system (1), the rotary grate (25) having the following: at least one rotary grate element (252, 253, 254) with a perforation of a plurality of slot-shaped openings (256); at least one bearing axle (81) by means of which the rotary grate element (252, 253, 254) is rotatably mounted; at least one cleaning device (125) attached to one of the rotary grate elements (252, 253, 254), wherein the cleaning device (125) comprises a mass element (127x) that is linearly movable relative to the rotary grate element (252, 253, 254) and has a plurality of piercing elements (129) having; the method comprising the following steps: rotating the rotating grate element (252,253,254) in a first direction (D1) and thereby moving the mass element (127x) of the cleaning device (125); initiating an accelerating movement of the mass element (127x); Hitting the mass element (127x) with a knocking effect on a stop surface (128a, 128b) of either the rotary grate element (252, 253, 254) or the cleaning device (125) for cleaning the rotary grate element (252, 253, 254) and with a piercing effect in the openings (256) by means of the lancing elements (129). A method for cleaning a rotary grate (25) of a biomass heating system (1) according to claim 16, wherein
the mass element (127x) is raised to a fall start position (F1, F2) when the rotary grate element (252, 253, 254) rotates to initiate the acceleration movement from which the mass element (127x) falls linearly under the influence of gravitational acceleration in order to generate the knocking effect on the rotary grate element (252, 253, 254).

Images