EP2778523B1 - Slag processing device - Google Patents

Description

The present invention relates to a slag treatment apparatus for treating slag from a combustion chamber of a waste incineration plant according to the preamble of claim 1. The invention further relates to a method for the treatment of slag by means of said slag processing apparatus.

In another aspect, the present invention relates to a slag processing grid for the production and treatment of slag in a slag conditioning apparatus.

Grates for incinerators are the expert from about EP-A-0 924 464 known which a method for. Cooling of such a grate with successively arranged, partially overlapping grate bars concerns. In this case, air is supplied by means of supply lines in a channel system arranged in the grate bars, which is finally guided through openings in the combustion chamber.

As slag in the field of waste incineration the solid residues present at the end of the combustion occurring in the combustion chamber are called.

These are discharged from the waste incineration plant by means of a de-scaling device, which conventionally comprises an intake shaft through which the slag falls from the combustion chamber into a tank filled with water. From this, the slag is generally discharged by means of a pushrod or a discharge chain on a Ausschubschurre or Ausschubbahn, from where they can be transported in deponierfähiger form.

For example, in DE-A-2539615 describes a slagger comprising a water-filled sheet pan into which a waste slag chute opens and on the curved bottom of a discharge piston is reciprocable, the slag discharged in the tub overshoots a rising discharge chute.

Another deslagging apparatus, in which at the end of a firing grate a substantially vertically arranged slag shaft opens above a slag tank provided with a water filling with an obliquely rising outfeed path, becomes approximately in EP-A-0363645 disclosed.

In addition, approximately in the DE-C-959 399 discloses a slag discharge channel filled with water, to which slag is supplied by a suitable device and into which dust also passes between the grates.

Next will be in DATABASE WPI Week 201303 Thomson Scientific, London, UK; AN 2012-R54D99 XP002703728 & CN 102730993 discloses a method for disposing of waste incineration ash, wherein the resulting fly ash and slag is taken up as raw material in cement clinker.

In order to increase the added value of waste incineration plants, great efforts have been made for quite some time to recover reusable materials from the slag. The focus is not only on the recovery of iron, but also the recovery of non-ferrous metals, especially aluminum or copper, but also precious metals such as silver, gold or platinum.

For recovery, the fine fraction is subjected to suitable separation in the first place. In the case of iron this can be recovered about by means of magnetic separation.

However, a separation can only be made on dry slag.

The wet slag discharged by means of the abovementioned prior art slag removal devices must therefore be dried with continuous redeployment over several weeks before the valuable substances can be recovered. Especially with regard to the recovery of aluminum, a significant proportion of the valuable material can be lost, even during drying alone. In the event that the recovery of mineral recyclables is sought, it is added that in the wet slag already Abbindereaktionen can take place, which makes a recovery from a technical or economic point of view pointless or even impossible.

Based on these disadvantages of wet sludging, devices for discharging dry slag have been proposed.

So will be in about EP-A-1882529 describes a method for separating residues from a thermal waste treatment, in which the residues are conveyed in cascade in webs and intermediate free falling sections over at least one step down, wherein the fine fraction is discharged by a gas flow.

Due to the gas flow required for this air classification, a relatively large amount of gas, in particular air, is introduced into the interior of the corresponding separating device. In order to prevent an unfavorable lowering of the temperature in the combustion chamber for the burn-out and the energy balance, it must be ensured that as little air as possible with too low a temperature in the combustion chamber, and in particular in its main combustion and burn-out zone. Furthermore, according to the EP-A-1882529 described method a spatial separation between the combustion chamber and separator, which entails that the slag has undergone a relatively strong cooling already during insertion into the separator and the resulting temperature of the slag may not be sufficient, for a better burn still combustible material to start in the slag. Furthermore, relatively expensive and maintenance-intensive devices are required for the separation of the fine fraction from the gas stream, such as a cyclone or filter.

The object of the present invention is thus to provide a simple and low-maintenance apparatus for the treatment of dry slag available, which allows optimal combustion of the slag and a cooling of the same to the desired temperature and further a separation of the slag into at least one fine fraction and a Coarse fraction allows without affecting the energy balance in the furnace.

The object is achieved according to the invention by the slag processing device according to claim 1. Preferred embodiments of the invention are given in the dependent claims.

Accordingly, the slag processing device according to the invention comprises a slag processing space in which slag from the combustion chamber of a waste incineration plant, in particular whose burn-out zone, treated, that is primarily cooled to the desired temperature, is.

The slag processing device is therefore generally not included in the combustion chamber, but generally constitutes a separate device arranged downstream of the combustion chamber. In particular, the treatment of the slag carried out in this device does not correspond to afterburning carried out in the combustion chamber. Nonetheless, the slag entering the slag processing room may still contain isolated combustible components.

Specifically, the slag processing room comprises a slag inlet for introducing slag into the interior of the slag processing room. The slag inlet may be in the form of a shaft through which the slag discharged from the burn-up zone passes into the interior of the slag processing space. However, it is also conceivable that the slag processing space adjoins directly to the firebox, that is, that the lower boundary of the firebox and the lower boundary of the slag processing space lie in the same plane. Thus, the term "slag inlet" also generally includes the transition between the firebox and slag processing room.

Opposite the slag inlet is a slag outlet for discharging slag from inside the slag processing room. This may be in the form of a shaft over which slag processed in the slag processing space is dumped into a sump.

The slag processing room further comprises a slag processing grid for cooling slag and for conveying it in the direction from the slag inlet to the slag outlet. In this case, a Schlackeaufbereitungsrost be used, the configuration of which corresponds to that of a known combustion grate. In particular, a slag processing grid with known grate blocks can be used. Conceivable in this respect, however, are grate plates, in particular grate plates extending over the entire width of the slag processing grid, or grate bars.

In order to ensure a particularly efficient cooling, according to a particularly preferred embodiment, the grate comprises water-cooled grate elements. Corresponding water-cooled grate elements are known to the person skilled in the art.

According to the invention, in the end of the slag processing grid facing the slag outlet, there are now openings through which the slag processing space is connected to a fine slag discharge space and which are designed so that at least one fine fraction of the slag is thrown through the openings into the fine slag discharge space, while the slag outlet into one slag outlet Grobschlackeaustragsraum opens to receive a coarse fraction of slag.

Obviously, according to the invention, openings are present in the end region of the slag processing grid facing the slag outlet, in which openings are also excluded in the area facing the slag inlet or along the entire extent of the slag processing grid are arranged.

The fact that there are openings in the slag processing grid for the discharge of at least one fine fraction of the slag, which thus have a certain size, it differs fundamentally from a common combustion grate, such as in DE-C-959 399 is disclosed, since in the latter a falling through of material as far as technically possible to be prevented and thus no openings for the discharge of a fraction of the material located on the grate are present.

Thus, in the said end region of the slag processing grid, slag parts of corresponding size, i. at least one fine fraction, through the described openings from the slag processing space into the fine slag discharge space, while larger sized slag portions, i. the coarse fraction, are conveyed to the slag outlet, over which they enter the coarse slag discharge room. Thus, bulky slag components are separated from the further components to be separated, which thus can be fed directly to the appropriate separation devices - such as an eddy current separation device or a separation table.

By the presence of a fine slag discharge space and a coarse slag discharge space and thereby allowing separation of the corresponding slag constituents, the present slag discharge apparatus further fundamentally differs from known apparatuses and methods in which all the slag is exposed to a single slag discharge duct a single slag pan is supplied, as in the in the DE-C-959 399 or the EP-A-0363645 disclosed devices is the case.

By virtue of the fact that the slag processing grid has at least partially distributed air feeds over its entire width for the controlled supply of air to the slag, it can be ensured according to the invention that the slag is cooled to the desired temperature and any still combustible constituents are ignited in the slag without Uncontrolled (false) air entering the combustion chamber at too low a temperature would adversely affect the energy balance in the combustion chamber.

The term "at least regionally" means that the grate can have air inlets over its entire length (i.e. over its entire extent in the conveying direction) or only in a region thereof.

As mentioned, the at least one fine fraction passes from the slag processing space via the openings into the fine slag discharge space, while the coarse fraction is conveyed to the slag outlet through which it passes into the coarse slag discharge space.

As a rule, therefore, the mean particle size of the at least one fine fraction is less than the mean particle size of the coarse fraction. The term "average particle size" refers to the respective smallest extent of the individual particles on average.

As explained below, the maximum particle size of the slag constituents contained in the fine fraction can be adjusted by the extent of the openings. Typically, the coarse fraction differs from the fine fraction in that the coarse fraction has slag constituents having a particle size of at least 200 mm, preferably at least 300 mm, more preferably at least 400 mm. Also in this context, the "smallest particle size" is the smallest expansion of the individual particles.

Especially in the case where several fine fractions are separated - i. from different areas of the slag processing grid - from the slag processing room to the fine slag discharge room, the fine slag discharge room may be divided into separate fine slag discharge room compartments arranged one after the other. In general, the respective Feinschlackeaustragsraumsabteile in the conveying direction are successively determined for a fine fraction having a larger average particle size than the respective Feinschlackeaustragsraumsabteil. Said Feinschlackeaustragsmittelabteile may be present in the form of successively arranged in the direction of funnels.

It is further preferred that the fine slag discharge space is associated with fine slag discharge means and coarse slag discharge space is associated with coarse slag discharge means, and the fine slag discharge means and coarse slag discharge means are designed to discharge the slag present in the respective space substantially airtight to the outside. therefore It is ensured that, except for the air supplied in a controlled manner via the air supply lines, no (false) air can reach the slag conditioning device or the combustion chamber.

As mentioned, the present invention is directed to the discharge of dry slag. According to a particularly preferred embodiment, the fine slag discharge means and / or the coarse slag discharge means are designed to discharge the slag in a substantially dry state. Thus they differ fundamentally from those in the DE-A-2539615 , the EP-A-0363645 and the DE-C-959 399 disclosed slag discharge systems in which the slag is taken up in a water filling and extinguished.

Preferably, the fine slag discharge means and the coarse slag discharge means form a sluice. It is conceivable, for example, that the fine slag discharge means in the form of shut-off devices, such as gate valves or butterfly valves, which can be actuated at different times. By means of these shut-off devices, a lock chamber can be enclosed, into which the fine slag is introduced when the first shut-off device is open and the second shut-off device is closed and can be executed when the first shut-off device and the second shut-off device are open. It is conceivable in this regard to arrange evacuation means for at least partial evacuation of the lock chamber with simultaneously closed shut-off devices. This allows the opening of the corresponding one Shut-off device to remove air from outside into said lock space and thus prevent it from entering the slag processing room.

By analogy, the coarse slag discharge means preferably also form a lock.

This can ensure that the interior of the entire slag processing device is closed airtight to the outside. Thus, the amount of air supplied to the slag processing space and the temperature can be accurately controlled; the problem of false air, which could get over the Schlackeaufbearbeitungsraum in the furnace, thus does not arise.

In addition, according to a further preferred embodiment, the slag inlet relative to the combustion chamber is airtight lockable. A shut-off may be indicated, for example, when it is feared that the processes in the slag processing room would adversely affect the processes in the firebox and vice versa in any way, be it that an excess of air could get from the slag processing room into the firebox, be that too much heat radiates from the firebox into the slag processing room. Due to the lockable slag inlet, these impairments can thus be minimized or even eliminated.

According to a particularly simple and therefore preferred embodiment from a manufacturing point of view, at least a part of the openings is formed in each case by a gap present between two spaced-apart grate elements. In case of that Accordingly, it is sufficient to omit in the construction of individual grate blocks in order to get to the openings according to the invention corresponding section of Schlackeaufbearbeitungsrost constructed of common grate blocks. In this regard, it is also conceivable or preferred if only a part of the respective grate block is omitted in order to form a corresponding gap.

Preferably, the grate elements are arranged such that they rest on the front side on the respective downstream in the conveying direction grate element. Thus, it follows that the openings are defined only by gaps formed between two widthwise spaced grate elements. Such a rust is thus fundamentally different from the one in EP-A-1882529 disclosed device in which residues are promoted cascading down under application of a shaking movement.

In the context of the present invention, "width direction" is understood to mean the direction transverse to the conveying direction of the grate. Accordingly, the "width of the grate" refers to the extent of the grate transverse to the direction of conveyance.

More preferably, the grate elements are spaced apart by at most 400 mm, more preferably by at most 300 mm, most preferably by at most 200 mm. Depending on the type or particle size distribution of the coarse fraction and the fine fraction but also other distances or other gap widths are conceivable.

In order to ensure optimum discharge of the fine fraction into the fine slag discharge space, the spaced apart grate elements are at least 5 mm apart, more preferably at least 10 mm, most preferably at least 20 mm apart. The openings formed by the corresponding gap according to this embodiment are sufficiently large to achieve a high yield of separated fine slag.

It is further preferred that the slag processing grid has openings with different cross-sectional areas, the expansion of the cross-sectional area of the openings increasing in the conveying direction.

This embodiment makes it possible to successively transfer several fine fractions of increasing average particle size in the Feinschlackeaustragsraum. In particular, it can be ensured by this embodiment that particles with a particularly low mean particle size, in particular sand, are removed early from the slag processing grid. Thus, the thickness of this layer of sand can be minimized or even eliminated, whereby the contact of the other slag parts with the Schlackeaufbereitungsrost and ultimately the cooling of these slag parts is improved.

As mentioned above, it is particularly advantageous for this embodiment, when the fine slag discharge space is divided into separate Feinschlackeaustragsraumabteile, wherein the respective Feinschlackeaustragsraumsabteile viewed in the conveying direction successively determined for a fine fraction having a larger average particle size than the previous one Feinschlackeaustragsraumsabteil. Thus, the sand removed separately from the slag processing grid can also be discharged separately from the slag conditioning apparatus from the fine fraction (s) having a larger average particle size.

According to a further aspect, the present invention additionally relates to a slag processing grid for the conveying and processing of slag comprising a plurality of grate elements arranged in a staircase manner in the conveying direction and thus forming grate steps. The body of these grate elements has a top wall forming a support surface and a front wall viewed in the conveying direction of the grate. The slag processing grid has openings for connecting a slag processing room to a slag discharge room in an end area intended to face a slag outlet. The apertures are configured to eject at least a fine fraction of the slag through the apertures into the fine slag discharge space. The upper wall and / or the front wall of the grate elements has a plurality of air ducts for the controlled supply of air to the garbage or slag. The air supply lines are divided into at least two groups, wherein the air supply lines of the first group is connected to a first air line for supplying a first amount of air and the air supply lines of the second group is connected to a second air line for supplying a second amount of air.

Particularly preferably, the first quantity of air differs from the second quantity of air. This means that the air ducts are designed to conduct different amounts of air to the different air supply lines.

According to a particularly preferred embodiment, the air ducts are each in the form of a separate duct system assigned to the respective group of air ducts or form part of such duct system Such a duct system may comprise, for example, an air distributor bar, from which individual air ducts branch off and lead to the air supply lines of the respective group.

In order to ensure that in each case different amounts of air are conducted to the air feeds of the individual groups, at least one part of the air lines is assigned at least one actuator for controlling the air flow. These actuators are usually in the form of known in the art flaps, valves or valves.

Thus, the grate of the present invention allows not only to respond to the differences across the length but also to the width differences. Thus, the required at the respective location for the cooling or the improved burnout of the slag air flow can be optimally adjusted. The same applies to the combustion chamber, in which the optimum setting of the required air flow contributes to the fact that the combustion can be optimized without the temperature in the combustion chamber being unnecessarily lowered, which would be the case, for example, with excessive introduction of primary air.

By the air feeders are designed such that the air can be supplied controlled, they differ from conventional air ducts of a combustion grate, in which large amounts of primary air for combustion via a simple construction of funnels and entering into this air ducts are to be introduced into the combustion chamber, whereby only one low distribution of air is possible. Furthermore, the air supply lines of the inventive grate differ completely fundamental of the air supply of a grate firing feeder located in front of the actual combustion grate, as it is approximately in DE 39 41 750 is described, which have primarily the goal to dry the feed.

As mentioned, the grate elements are in the form of grate blocks, wherein a plurality of grate blocks juxtaposed over the width of the grate each form a grate step. It is also conceivable that the grate elements are in the form of grate plates, in particular in the form of over the entire width of the grate extending grate plates, or grate bars.

According to a particularly preferred embodiment, the grate elements of a single grate stage have air feeds of only a single group. However, it is also conceivable that a single grate stage or its grate element (s) has air supply of different groups.

In general, the air ducts are in the form of air ducts with corresponding, spaced-apart orifices.

According to a preferred embodiment, at least a part of the air inlets present in a grate stage is arranged in a straight line running transversely to the conveying direction.

A very accurate distribution of the introduced amount of air to the respective areas of Verschubrosts can be achieved, for example, if there are 5 to 30 air supply per grate stage.

According to a particularly preferred embodiment, the grate according to the invention constitutes a grate for the slag processing device described above.

The preferred embodiments described in connection with the grate also represent preferred embodiments of the slag processing apparatus. Vice versa , all of the inventive and preferred features described in connection with the slag conditioning apparatus are preferred features of the grate.

1. a) Schlacke aus dem Feuerraum der Müllverbrennungsanlage über den Schlackeeinlass in das Innere des Schlackeaufbereitungsraums eingeführt wird,
2. b) die Schlacke mittels des Schlackeaufbereitungsrosts abgekühlt wird, indem Luft über die Luftzuführungen kontrolliert zugeführt wird, und in Richtung vom Schlackeeinlass zum Schlackeauslass hin gefördert wird,
3. c) die mindestens eine Feinfraktion der Schlacke durch die in dem dem Schlackeauslass zugewandten Endbereich des Schlackeaufbereitungsrosts vorliegenden Öffnungen in den Feinschlackeaustragsraum abgeworfen wird, und
4. d) die Grobfraktion der Schlacke über den Schlackeauslass in den Grobschlackeaustragsraum aufgenommen wird.

In addition to the described slag processing apparatus and the described grate, in another aspect, the present invention relates to a method for processing slag by means of said slag conditioning apparatus comprising the steps of

1. a) slag is introduced from the firebox of the waste incineration plant via the slag inlet into the interior of the slag processing space,
2. b) the slag is cooled by means of the slag processing grate by controlled supply of air via the air supply lines and is conveyed in the direction from the slag inlet to the slag outlet,
3. c) the at least one fine fraction of the slag is dropped into the fine slag discharge space through the openings in the end region of the slag processing grid facing the slag outlet, and
4. d) the coarse fraction of slag is taken up into the coarse slag discharge space via the slag outlet.

As mentioned, the present invention on the one hand allows at least one fine fraction to be separated from a coarse fraction before the latter is discharged from the slag processing space and, on the other hand, to optimally cool the slag in the slag processing space.

According to a further aspect, the present invention thus also relates to the use of the above-described grate for separating at least one fine fraction of the slag from a coarse fraction of the slag and for cooling the slag.

As also noted, the process is primarily directed to the discharge of dry slag. According to a particularly preferred embodiment of the method described above, the fine fraction and / or the coarse fraction are thus discharged from the slag processing device in a substantially dry state.

Fig. 1

eine technische Zeichnung eines Ausschnitts einer Müllverbrennungsanlage enthaltend einen Feuerraum und eine Schlackeaufbereitungsvorrichtung gemäss der vorliegenden Erfindung;

Fig. 2

einen die Schlackeaufbereitungsvorrichtung enthaltenden Ausschnitt aus Fig. 1;

Fig. 3

eine technische Zeichnung einer Schlackeaufbereitungsvorrichtung gemäss einer weiteren Ausführungsform der vorliegenden Erfindung in perspektivischer Ansicht;

Fig. 4

eine technische Zeichnung des Rosts der in Fig. 3 gezeigten Ausführungsform in perspektivischer Ansicht;

Fig. 5

eine technische Zeichnung zweier Rostplatten eines erfindungsgemässen Rostes in perspektivischer Ansicht, wobei eine erste Rostplatte Luftzuführungen einer ersten Gruppe und eine zweite Rostplatte Luftzuführungen einer zweiten Gruppe aufweist, welche jeweils mit unterschiedlichen Luftleitungen zur Versorgung mit unterschiedlichen Luftmengen verbunden sind; und

Fig. 6

eine einzelne Rostplatte des Rostes gemäss Fig. 5 mit entsprechender Verteilerleiste und davon abzweigenden Luftkänalen.

The invention will be further illustrated by the accompanying figures. From these shows:

Fig. 1

a technical drawing of a section of a waste incineration plant comprising a furnace and a slag processing apparatus according to the present invention;

Fig. 2

a section containing the slag processing device Fig. 1 ;

Fig. 3

a technical drawing of a slag processing apparatus according to another embodiment of the present invention in a perspective view;

Fig. 4

a technical drawing of the rust of the Fig. 3 embodiment shown in a perspective view;

Fig. 5

a technical drawing of two grate plates of a grate according to the invention in a perspective view, wherein a first grate plate air supplies a first group and a second grate plate air supplies a second group, which are each connected to different air lines for supplying different amounts of air; and

Fig. 6

a single grate plate of the grate according to Fig. 5 with corresponding distributor strip and branching off air channels.

As in Fig. 1 the waste incineration plant comprises a combustion chamber 2, which is preceded by a refuse hopper 4 with a subsequent refuse shaft 6, which is connected via a firebox inlet 8 to the combustion chamber 2.

The combustion chamber 2 comprises a combustion grate 10 in the form of a feed grate forming its lower boundary. The combustion grate 10 is divided into four combustion grate sections 10a, 10b, 10c, 10d, each of which is associated with two push-pull actuatable drives 12a, 12b, 12c, 12d. (Of these two drives is in Fig. 1 only one shown.) In the embodiment shown, the first three Verbrennungsrostabschnitte 10a, 10b, 10c viewed in the conveying direction F in the same, slightly inclined in the conveying direction down plane, while the fourth feed grate portion 10d down and offset according to the shown Embodiment is preferably arranged in a substantially horizontal plane.

All four combustion grate sections 10a, 10b, 10c, 10d each have an underwinding section 14a, 14b, 14c, 14d arranged below the corresponding section, into each of which a separate primary air line 16a, 16b, 16c, 16d opens and which is intended to convey primary air supply corresponding primary air ducts in the combustion grate 10 the fuel bed.

In the conveying direction F downstream of the fourth combustion grate section 10d, a slag discharge edge 18 with a slag discharge chute 20 adjoining it is arranged. The slag discharge chute 20 leads via a slag inlet 22 into the interior of a slag processing space 24 of a slag processing device 26. The slag inlet 22 is assigned a sluice gate 28 which is designed such that it closes off the slag processing space 24 in an air-tight manner when needed.

As in particular in Fig. 2 shown, the slag processing device 26 has a bottom of the slag processing space 24 forming slag processing grid 30 in the form of a feed grate, which is arranged in a horizontally extending plane and to which two push-pull actuators 32 zugordnet, wherein in Fig. 2 only a single drive is shown. Below the slag processing grid 30, a fine slag discharge space 34 is arranged. The fine slag discharge space 34 is thus separated from the slag processing space 24 by the slag processing grid 30, but is connected to the latter by openings as will be detailed below.

In the embodiment according to Fig. 4 For example, the slag processing grid 30 has a first slag processing grid area 30a facing the slag inlet 22, in which the slag conditioning grid 30 has air feeders 36 distributed over its entire width. As in particular from Fig. 6 is visible, these air ducts 36 are arranged in the embodiment shown in the foremost region of a present as a grate plate 44 grate element in two groups, the air supply lines of the first group 36 a along a straight line transverse to the conveying direction F are arranged side by side and the air feeds of the second group 36 b in a straight line parallel to the first straight line.

The air feeders 36 are connected to an air blower 38, from which a first air line 40a to a first, the first group 36a associated Air distributor bar 42a and a second air line 40b branches off to a second, the second group 36b associated air distributor bar 42b. Consequently, the air supply lines of the first group 36a and the air supply lines of the second group 36b are supplied with air in each case via a separate air distributor strip 42a or 42b. It is conceivable in this regard, however, that individual air inlets are supplied separately with air, in particular that each individual air supply is supplied separately with air.

As in particular from Fig. 5 it can be seen, the first air line 40a and the second air line 40b are each associated with an actuator 41a or 41b for controlling the air flow through the respective air line. By means of these actuators 41a, 41b, the air distribution strip 42a associated with the first group 36a is supplied with a first quantity of air and the air distribution strip 42b allocated to the second group 36b is supplied with a second quantity of air, wherein the first quantity of air differs from the second quantity of air. As well as from the Fig. 6 can be seen, in the embodiment shown of the air manifold strips 42a, 42b respectively from individual air ducts 39a and 39b from which each open in one of the air feeds 36 of the first group 36a and the second group 36b. These air ducts 39a, 39b are subdivided into a first section 391a or 391b extending from the air distribution strip to the grate plate 44, in which the air ducts 39 are in the form of air ducts, and a second section 392a or 392b, in which the air ducts pass through pass the grate plate 44.

The first slag processing grate area 30a closes in the in Fig. 4 shown embodiment in the conveying direction F on a second slag processing grate area 30b. This has in said embodiment, no air supply, but is - as shown schematically in the figure - cooled by water. The water is circulated in a circuit in which a heat exchanger 43 and a fan associated therewith 45 is present for cooling the water and the cooled water is passed by means of a pump 47 through corresponding cavities in Schlackeaufbereitungsrost 30 and back to the heat exchanger 43. Although not explicitly shown in the figure, it is preferred that - in addition to the second slag processing grate area 30b - also other slag processing grate areas, in particular the first slag grate area 30a, have water-cooled grate elements. Furthermore, it is conceivable that air feeds - in addition to the first slag processing grate area 30a - are also present in other slag processing grate areas, in particular in the second slag processing grate area 30b.

In the first and second slag processing grate area 30a, 30b, in the in Fig. 4 Slabaufbereitungsrost 30 shown formed by grate plates 44 which extend over the entire width of the Schlackeaufbereitungsrosts 30 shown. It is also conceivable, of course, that these Schlackeaufbereitungsrostbereiche are constructed of rust blocks.

The grate plates 44 have a support surface forming a top wall 53 and a viewed in the conveying direction F of the grate front wall 55, wherein in the illustrated embodiment, the air supply lines 36 are arranged in the upper wall or via the upper wall into the slag processing space 24 open. It is also conceivable that the openings in the front wall 55 are arranged.

At the second slag processing grate area 30b, a third slag processing grate area 30c adjoins in the conveying direction F. In this, the individual grate elements in the form of (also each having a top wall 53 'and a front wall 55' having) grate blocks 49 are formed, which in the width direction, i. are arranged transversely to the conveying direction F, spaced from each other, so that there is a gap between two grate blocks. The gaps form the above-mentioned openings 46, via which the slag processing space 24 is connected to the fine slag discharge space 34. In the illustrated embodiment, in a first grate stage 48a, the gap widths are larger than the gap widths of a second grate stage 48b arranged downstream of the first grate stage in the conveying direction F. Of course, it is also conceivable that at least a portion of the gaps forming the openings is formed by the omission of only a portion of the respective grate block.

The embodiments according to Fig. 1 or 2 and Fig. 3 differ essentially in the design of Feinschlackeaustragsraums 34th

In the in Fig. 1 2, the fine slag discharge space 34 is formed in the form of a funnel 52. In the funnel neck 54, ie the narrowest region of the funnel, there are fine slag discharge means 50 in the form of two fine sludge stopper slides 51a, 51b arranged one above another, which in each case alternately release the passage 56 defined by the funnel neck 54 or close it airtight and thus form a sluice. Below the lower Feinschlackeabsperrschiebers 51b and in extension of the funnel neck 54, a conveyor belt 58 is arranged.

In particular, in the event that the deposition of a plurality of fine fractions is provided, a plurality of, each forming a Feinschlackeaustragsraumabteil funnel may be provided, which are arranged one after the other in the conveying direction F.

In the in Fig. 3 In the embodiment shown, the fine slag discharge space 34 is designed in the form of a trough with a base arranged in a substantially horizontally extending plane. In addition, in said embodiment, two push rods 57a, 57b are provided, which can be moved back and forth along the bottom and each have a push plate (not shown) at the front. These push taps are designed to push the fine slag located at the bottom of the fine slag discharge space in the thrust direction. Immediately below this pushrod 57a, 57b a Feinschlackeabsperrschieber 51c is arranged, with which the pushrod form a lock.

Both in the in Fig. 1 and 2 as well as in the Fig. 3 1, a coarse slag discharge edge 60 is arranged in the conveying direction F downstream of the slag processing grid 30. Adjoining this is a slag outlet 62, which opens into a coarse slag discharge space 64. The coarse slag discharge space 64 is in the in Fig. 1 or 2 embodiment shown in the form of a coarse slag discharge chute 66 formed.

The slag outlet 62 is in the in Fig. 1 and 2 shown embodiment a Grobschlackeabsperrschieber 68 assigned. In the case shown that the coarse slag discharge space is designed in the form of a coarse slag discharge chute, the passage defined by the latter can be released in a controlled manner by means of the coarse sludge sludge shifter 68. The passage opens into a coarse slag collecting trough 70. This can be conveyed out of the coarse slag discharge space 64 with the coarse slag closure slide 68 closed via the door 72 provided for this purpose. Thus, the Grobschlackeabsperrschieber 68 and the gate 72 form a lock. They thus serve as coarse slag discharge means 73 for the airtight discharge of the slag. Alternatively, to convey the slag by means of the coarse slag collecting tank shown on the gate to the outside, and a conveying member for mechanical airtight discharge of the slag can be provided.

In operation, the waste to be incinerated by means of a crane, of which in Fig. 1 only the crane claw 76 is shown, dropped into the refuse hopper 4 and the subsequent refuse chute 6.

At the output of the refuse shaft 6, the refuse is pushed by means of appropriate feed plunger 9 through the firebox inlet 8 into the firebox 2 or onto the firing grate 10, from where the refuse is conveyed in the direction of the firebox outlet 8 in the form of a firebox. The waste passes through several combustion phases, namely a drying phase, an ignition phase, a main combustion phase and a burnout phase. Associated with these phases are respective zones on the combustion grate 10, ie, a drying zone, an ignition zone, a main combustion zone and a burnout zone which respectively communicate with the combustion sections 10a, 10b, 10c, 10d in FIG Fig. 1 correspond.

In the burn-out zone or in the combustion section 10d, the waste passes into slag, which is pushed over the slag-throwing edge 18 and subsequently reaches the interior of the slag-preparing space 24 via the slag-throwing shaft 20 or the slag inlet 22.

The slag is conveyed toward the slag outlet 62 via the slag processing grid 30 and thereby cooled in the first slag processing grid area 30a by air supplied through the air feeders 36. In the event that there are still combustible components, which can be detected, for example, by means of suitable sensors or cameras 74, the flow velocity or the momentum of the air can be such be adapted to start these ingredients, thus contributing to an improved burnout and ultimately to an increased slag quality.

In the downstream second slag processing grate area 30b in the conveying direction F, the slag is then further cooled by contact with the water-cooled grate plates 44 before entering the third slag processing grate area 30c. It is conceivable, in particular in the second Schlackeaufbereitungsrostbereich 30b passages provide with relatively small cross-sectional area through which drain sand in the slag and thus can be removed from Schlackeaufbereitungsrost 30 to the contact of the other slag parts with the Schlackeaufbereitungsrost 30 and ultimately the cooling of these slag parts to improve.

The slag is then conveyed through the third slag processing grate area 30c, through which openings slug parts of appropriate size, i. the fine fraction or fine slag falling from the slag processing room 24 into the fine slag discharge room 34, while slag parts of larger dimensions, i. the coarse fraction or coarse slag are conveyed to the outlet via the third slag processing area 30c and are pushed over the coarse slag discharge edge 60 in the direction of the coarse slag discharge space 64.

By means of Grobschlackeabsperrschiebers 68 defined by the coarse fractionation chute 66 passage be released controlled. When Grobschlackeabsperrschieber 68 open the coarse slag falls into the coarse slag collection tray 70. This can be transported with closed Grobschlackeabsperrschieber 68 through the door 72 provided for this purpose to the outside.

The air entering the coarse slag discharge space upon opening the door 72 can be removed from said space by appropriate means before the coarse sludge trap valve 68 transitions to the open state.

Thus, bulky slag components are separated from the further components to be separated, which thus can be fed directly to the corresponding separation devices to recover reusable materials from the slag.

Reference Signs List

2

firebox

4

waste hopper

6

garbage chute

8th

Combustion chamber inlet

9

loading ram

10

combustion grate

10a-d

Grate sections

12a-d

Drives of the combustion grate

14a-d

Under wind chamber

16a-d

Primary air supply

18

Slag discharge edge

20

Slag chute

22

slag inlet

24

Slag processing space

26

Slag processing device

28

Gate valves

30

Slag processing rust

30a-c

Slag processing rust areas

32

Drives of slag processing grate

34

Feinschlackeaustragsraum

36

Air inlets of the slag processing grid

36a, b

first or second group of air supply

38

air blower

39a, b

air ducts

391a, b

first section of the air ducts

392a, b

second section of the air channels

40a, b

air lines

41a, b

actuators

42a, b

Air Distribution Unit

43

heat exchangers

44

grate plate

45

fan

46

openings

47

pump

48a, b

grate step

49

grate block

50

Feinschlackeaustragsmittel

51a, b, c

Feinschlackeabsperrschieber

52

funnel

53, 53 '

upper wall (bearing surface) of the grate element

54

funnel neck

55, 55 '

front wall of the grate element

56

Passage of the funnel neck

57a, b

thrust ram

58

conveyor belt

60

Coarse slag discharge edge

62

slag outlet

64

Grobschlackeaustragsraum

66

Coarse slag chute

68

Grobschlackeabsperrschieber

70

Coarse slag collection tray

72

gate

73

Grobschlackeaustragsmittel

74

Sensor or camera

76

sick Rail

Claims (14)

1. A slag processing device of a waste incineration facility for processing slag that is supplied from a combustion chamber (2) of the waste incineration facility to this slag processing device, including a slag processing chamber (24),
   the slag processing chamber having a slag inlet (22) for introducing slag into the interior of the slag processing chamber (24),
   having a slag outlet (62), situated opposite from the slag inlet (22), for discharging slag from the interior of the slag processing chamber (24), and
   having a slag processing grate (30) for cooling slag and for conveying it in the direction of the slag inlet (22) toward the slag outlet (62),
   characterized in that openings (46) are present in the end area of the slag processing grate (30) facing the slag outlet (62), via which the slag processing chamber (24) is connected to a fine slag discharge chamber (34), and which are designed in such a way that at least one fine fraction of the slag is ejected through the openings (46) and into the fine slag discharge chamber (34),
   the slag outlet (62) opens into a coarse slag discharge chamber (64) for receiving a coarse fraction of the slag,
   and the slag processing grate (30), at least in areas, has air feeds (36) distributed over its entire width for the controlled feed of air to the slag.
2. The slag processing device according to Claim 1, characterized in that fine slag discharge means (50) are associated with the fine slag discharge chamber (34), and coarse slag discharge means (73) are associated with the coarse slag discharge chamber (64), and the fine slag discharge means (50) and the coarse slag discharge means (73) are designed in such a way that the slag present in the particular chamber (34 or 64) may be discharged to the outside in an essentially airtight manner.
3. The slag processing device according to one of the preceding claims, characterized in that the fine slag discharge means (50) and the coarse slag discharge means (73) each form a lock.
4. The slag processing device according to one of the preceding claims, characterized in that at least a portion of the openings (46) are formed in each case by a gap that is present between two spaced-apart grate elements (49).
5. The slag processing device according to Claim 4, characterized in that the grate elements (49) are spaced apart from one another by at most 400 mm, preferably by at most 300 mm, most preferably by at most 200 mm.
6. The slag processing device according to Claim 4 or 5, characterized in that the spaced-apart grate elements (49) are spaced apart from one another by at least 5 mm, preferably by at least 10 mm, most preferably by at least 20 mm.
7. The slag processing device according to one of the preceding claims, characterized in that the slag inlet (22) is closable with respect to the combustion chamber (2) in an airtight manner.
8. The slag processing device according to one of the preceding claims, characterized in that the slag processing grate (30) has openings (46) with different cross-sectional areas, with the extension of the cross-sectional area of the openings (46) increasing, viewed in the conveying direction (F).
9. The slag processing device according to one of the preceding claims, characterized in that the air feeds (36) are designed to cool the slag and/or to fan material that is still combustible in the slag.
10. The slag processing device according to one of the preceding claims, wherein the slag processing grate for conveying and thermally treating waste or for conveying and processing slag includes a plurality of grate elements (44, 49) that are arranged one on top of the other in a step-like manner in the conveying direction and thus form grate steps, with a body that has an upper wall (53 or 53') that forms a support surface, and a front wall (55 or 55'), viewed in the conveying direction of the grate, characterized in that the upper wall and/or the front wall of the grate elements have/has multiple air feeds (36) for the controlled feed of air to the waste or to the slag, and the air feeds are divided into at least two groups (36a, 36b), the air feeds of the first group (36a) being connected to a first air line (40a) for supplying a first quantity of air, and the air feeds of the second group (36b) being connected to a second air line (40b) for supplying a second quantity of air.
11. The slag processing device according to Claim 10, wherein the first quantity of air is different from the second quantity of air.
12. The slag processing device according to Claim 10 or 11, characterized in that the grate elements are grate blocks (49), and multiple grate blocks situated next to one another over the width of the slag processing grate in each case form a grate step (48a, 48b).
13. Use of a slag processing device having a slag processing grate according to one of Claims 10 to 12 for separating at least one fine fraction of the slag from a coarse fraction of the slag, and for cooling the slag.
14. A method for processing slag by means of a slag processing device according to one of Claims 1 to 12, including the steps:

    a) slag from the combustion chamber (2) of the waste incineration facility is introduced into the interior of the slag processing chamber (24) via the slag inlet (22),

    b) the slag is cooled by means of the slag processing grate (30), in that air is supplied via the air feeds (36) in a controlled manner, and the slag is conveyed in the direction from the slag inlet (22) toward the slag outlet (62),

    c) the at least one fine fraction of the slag is ejected into the fine slag discharge chamber (34) through the openings (46) that are present in the end area of the slag processing grate (30) facing the slag outlet (62), and

    d) the coarse fraction of the slag is received into the coarse slag discharge chamber (64) via the slag outlet (62) .

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