EP2841860A2

EP2841860A2 - Device for thermally treating a wet substrate comprising a centrifugal shaft and method for the operation thereof

Info

Publication number: EP2841860A2
Application number: EP13723441.5A
Authority: EP
Inventors: Michael GEISINGER
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-04-28
Filing date: 2013-04-27
Publication date: 2015-03-04
Also published as: WO2013160480A2; CH706388A2; WO2013160479A3; WO2013160480A3; WO2013160479A2; EP2841859A2

Abstract

The invention relates to a device for thermally treating a wet substrate to increase the dry substrate content of said wet substrate. Said device comprises at least one centrifugal shaft which is arranged in a housing and on which means for the fragmented conveyance of the wet substrate in a drying chamber of the device are arranged. Said device comprises an inlet for the web substrate and an outlet for the at least partially moisture-reduced substrate and the drying chamber comprises an inlet and an outlet for the drying air and is designed for inputting thermal energy. The substrate outlet of said device is designed to control the amount of at the least partially moisture-reduced substrate present in the drying chamber. No drawing

Description

The present invention relates to a device for the thermal treatment of a moisturizing substrate according to the preamble of claim 1. The invention also relates to a method for the thermal treatment of a moist substrate according to the preamble of claim 11. The moist substrate may also be a solution or suspension containing dry matter. The housing referred to below may be a housing accommodating the device or else a housing accommodating the spinning shaft with a drying space. For the drying of bonding-prone materials, various methods use the method of returning some of the dried material to the drying process to reduce the relative humidity of the resulting mixture. Also known are so-called spin-wave dryers in which rotating blade waves throw up the material and thus create the optimum conditions for convection drying. It is an object of the present invention to provide a process which permits a simple and optimal drying of adhesives that tend to adhere, in particular especially Klaerschlamm, allowed with spin dryers, and a particularly suitable device. The same method can also be applied on the one hand to the drying of any, even for non-sticky materials, on the other hand, on the other extreme of the extremes, on liquids, such as bark and Gaerreste from biogas plants. The principles outlined therein can also be applied to any material.

The core of the process is that already dry material is in the dryer, either because - in the case of a portion drying - only part of the material removed and another part is left in it, either because - in the case of a passage drying, as shown for example in drawing 1 - the regulation is designed accordingly. This eliminates the need to mix damp and dry material in front of the dryer and eliminates the need to return the dry material after the dryer, back to the dryer or to a mixer in front of it.

The invention can be implemented with any spin dryer. The drawing 1 shows a device particularly suitable for this purpose and relates to the drying of sewage sludge, but can be used in this way and analogously for all other applications. It takes up elements from the patent applications 259/12 and 585/12 and develops them further.

The sewage sludge comes from the outlet of the centrifuge (a), where it has been brought from a liquid to a muddy consistency, and falls directly into the drier's supply hopper (b). This is designed so that the walls are relatively steep, if not vertical, so that the Klaerschlamm presses itself by its own weight in the conveyor screw located below. The hopper is provided at the dryer opposite end with an outlet, which allows, if necessary, by reversing the rotary Direction of the screw, the container relatively easy to empty. Likewise, at least one of the side walls can be made removable or hinged for this purpose. Since the dryer can stand even once, either for maintenance or other reasons, the sludge centrifuge is however inexhaustible, or if, for some other reason, the centrifuge is conveying more sludge than the drier can take up and dry, is under the supply hopper (B) a conveyor device (c) attached, which receives the Klaerschlamm sometime overflowing when the dryer is stopped and promotes in a corresponding buffer storage device. This conveyor device can run continuously, or be turned on automatically when material hits it. If the interruption lasts longer, the ejection of the centrifuge (a) can be made pivotable and the material can be conveyed into containers, which can then be charged and removed.

In this type of spin dryers, the material travels from the inlet (s), along the spinner shaft, to the outlet (g), which is regulated by a controlled extraction - here represented in the form of a screw conveyor. So not only the residence time of the material can be regulated, but - in the present case particularly important - the amount of material in the dryer.

For a quickest possible mixing, the sewage sludge can be introduced in several places in small doses. In Fig. 1, the material inlet (e) is not quite attached to the edge of the dryer, but rather a long way behind so that the introduced wet material mixes with dry material from both sides. Depending on the nature of the sewage sludge, the screw conveyor runs continuously during the filling phase, or the filling phase is divided into intervals. In the pausing breaks, the moist material mixes because of the dry and the risk of lumping is reduced. The mixing effect can be influenced by the number and size of the throwing blades, as well as by the geometry of the throwing blades. Thus, a triangular blade can still enhance the effect already given in the arrangement of individual blades, that the material is conveyed by the upward movement of the blades, not only upwards but also to the side.

The material can be thrown up turbulently along the entire route, or increasingly homogeneously thrown up on the way through the drying, the closer it approaches the ejection (g). Again, the geometry of the spinning shaft can be used by, for example, no longer individual blades in the rear, the material aufwerden, but continuous strips, as shown in the drawing 1 also. Since Klaerschlamm is a very sticky material, the mixture ratio is also a special one. According to the invention, a relatively dry mixture is run through the dryer, which moves by 85% dry matter content (TS). This mixture has proven itself in municipal Klaerschlaemmen. If a final moisture of 90% TS is to be achieved, the input mixture will have approx. 80% DM. The values may vary depending on the sewage sludge, but especially for municipal sewage sludge a mixture is used that is clearly above a 50:50 dry / wet mixture and has a TS content of at least 65-70%. There are various ways to regulate the introduction of sewage sludge. One that offers itself is to watch the temperature in the dryer. If moist material is introduced (e), the temperature in the dryer drops. Once it has mixed with the surrounding dry or dry material and begins to dry itself, the temperature starts to rise again. Thus, the material entry can be controlled relatively easily via an upper temperature limit, which starts the filling and a lower temperature limit, which stops the filling. If the inlet temperatures fluctuate, for example if the drying heat is produced with the sun, or for another reason, the temperature values can be adjusted dynamically to the fluctuating inlet temperature of the drying air. Since the mixture is relatively dry and by the Nachfüuellen relatively little wetter, the drying temperature will be higher at the inlet temperature than other processes. For the control, a single temperature probe suffices when the air exits the drying chamber. A series of temperature probes along the material path - in Figure 1 this corresponds along the spin shaft (f) - even allows automated flexible response to changing inlet moisture of the material. If the dryer is heated from various heat sources, which may be the case when using the Abwaerme an internal combustion engine, for example, where the heat is available in the form of hot exhaust gases and warm water from the Motororkuehl ment, the air heated with it single stream, or - as described in the patent applications 259/12 and 585/12 - are divided into several air trains in the dryer, each of which heat a separate segment. These segments can be open, in that a pair of ventilators in each case blows in and out of the given draft, in a given area the path of the material through the dryer. These segments can also be separated by a partition, or in extreme cases even distributed to several dryer units. The introduction of the air can be introduced laterally from both the one and the other side of the spinning shaft (s) according to a method described in the patent applications 259/12 and 585/12, as well as the possibility exists, the air forehead and To introduce the axle side of the shaft. This frontal and the aft side can also Luftwroeme be introduced from different sources of energy, in extreme cases, heated from one side and from the other side only to be cooled.

For sewage sludge and other materials it is recommended to cool the material after drying. For all materials, cooling is also recommended for reasons of thermal efficiency, since the cooling air can again carry a considerable part of the moisture out of the material. In accordance with the invention, this is done either by the drying chamber fitted with the centrifugal shaft, for example in a ventilated conveyor screw. If a segment conveyor screw is used, the material is not only conveyed, but additionally mixed. - But also the drying chamber itself can be used for cooling, either because according to the principle described above of one of the selected segments with fresh, unheated, or even cooled ambient air is leaking, either because in a segment, or over the entire drying chamber the burner is switched on and off while the fresh air fan is passing through. In the patent application 585/12 it is described that in this type of device it is also possible to fire directly into the material, be it into the hollow space which the thrown material describes above the spinning shaft, or at another point. In this case, either the burner can heat a segment directly, while another segment is only cooled, or alternately fire only the burner or only the fan in a segment, or in the entire drying chamber, or blow.

The removal of material can - as described in the patent application 585/12 - over the wave load can be controlled. It may be useful to carry out the removal in each case after a filling interval, so that the wet material meets as much as possible dry or pre-dried material. Although the basic advantage of this device is that backmixing is not required, it does not mean that it is closed. A possible execution of such a Materialrueckfuehrung (h) is shown in the drawing 1. Thus, a drying according to the classical principle, the return and the mixing of the materials before or in the dryer is conceivable. In drawing 1, for the removal of dry, or at least dried material, a similar construction, as for the removal (g) is chosen, in which the material falls down in an opening, or even by the spin shaft is pressed into this. Below the opening is a conveyor mechanism - shown in the drawing in the form of a conveyor screw - which returns the material and presses it back into the dryer at a suitable location. In drawing 1, the same height of the spinning shaft was chosen, on which also the moist material is introduced (e). The outlet of the return channel is schraeg. The escaping material is carried along by the rotating spinning shaft. For multi - segment, or even multiple, dryer applications, this return may involve multiple segments or even dryer units. In the drawing 2 more locations of a possible Rückfuehrung are shown. Another possibility is to suck the material pneumatically at one point of the drying chamber and reinsert it at another. The transport is also theoretically possible in the other direction, so that a Materialrueckfuehrung can be a Materialvorfuehrung.

In connection with the cooling of the material described above, this may mean that the material recycling is used for repeated heating and cooling the material. Transferred to the drawing 1 this could mean that the left half is heated and the right half is just chilled. This constellation, in which the material circulates in the spin dryer, is also conceivable with a different combination of energy sources and Luftzuegen. The process described in this patent is suitable not only for sewage sludge and other very humid materials, but also for processing liquid solutions into powder, in a spin dryer as described here, or any other spin dryer. The liquid is introduced into the spin dryer, by any suitable method, which wets dry or pre-dried material in the dryer and then dried again. This is of particular interest to Guelle and Geraldae, but is not limited to these materials. A heat recovery can improve the energy efficiency. Since the drying of liquid solutions is particularly energy-intensive, the possibility should be mentioned at this point not only to produce the heat directly, via a fuel, or to use any available Abwaermequellen, but also renewable energy sources, such as sun, heat, wind energy, or other use. Solar and wind energy can also be used to generate the necessary mechanical energy for moving the spinning shaft (s), the fan and other consumers. In the case of solar, wind and other energy sources, the temperature level available for drying may vary. In the case of materials such as bark or gore residues, or in other materials where a certain degree of sanitization is desired, the material is already sanitized in the course of the drying process at sufficiently high temperatures. At entry temperatures of the drying air in the middle temperature segment, the drying material will not reach the temperature required for the sanitation until the end. In this case, it is worthwhile to connect the dryer with an insulated, or even heated buffer tank, in which it is kept at the level of the outlet temperature for a while, so that the desired sanitation occurs. At inlet temperatures in the low temperature segment, the material is dried, but never reaches the temperature necessary for the hygienization. In this case, for portion driers, the drying phase, with continuous dryers in each case in the last segment, the material is reheated with an additional energy source.

Further technical additions will now be described which relate in particular to the design of spin-wave dryers in general and to the devices described in this document and in patent applications 259/12 and 585/12 in particular.

The drawing 3 represents a portion dryer. For the removal of material (g) a Zellradschleusen-like device was selected, which extends over a portion or over the entire length of the spinning shaft, the rotational movement empties the dryer. However, in the drying process described above, this means that either the wet and the dry material are introduced simultaneously or, in the simplified form, the dried material is not completely emptied and what stays in it for the next mix with wet material is ready. This eliminates the need to return the dried material, as well as an eventual mixer in front of the dryer. The amount of material can be relatively easily regulated by the wave load. The timing of emptying the dryer as well, possibly in combination with moisture control. This operating mode not only refers to the described dryer devices, but to each spin dryer, which is used for this type of drying process. An alternative to the rotary valve may be a conveyor screw. In the drawing 4 various small technical supplements are shown. First of all, the throwing blades have different angles of incidence so that it is possible to achieve different throwing directions. Likewise, air intake devices (y) were attached to the centrifugal shaft and, thanks to a suitable geometry, which is not more closely defined here, the effect that the rotational movement The aim of the spinning shaft is to draw the air escaping from the air inlet (m) into the shaft, but also into the material eyelid described by the throw motion, which promotes the mixing of drying air and material. The feeders (y) may be individual elements attached to the blades or devices mounted over the entire length of the spinning shaft. The air inlet (m) is mounted relatively close to the material after it is thrown in the desired direction by a directional baffle (k). So it comes after leaving an immediate contact with the material. Although rejuvenation of the air inlet (m) means more effort for the fan, the air penetrates deeper into the layer of thrown-out material and the contact between the drying air and the material is intensified. In addition, in drawing 4, a steep angle of incidence in the opposite direction of the ascending material was chosen.

In the drawing 4 also a heating (I) of slide plate (i), wave shell (j) and guide plate (k) is shown, which can be done in various ways. In the present presentation, the drying air, which is usually very high in spin dryers when Eitnritt in the dryer and moves between 300 and 800 degrees Celsius, first to the slide plate (i), the wave shell (j) and the baffle (k ), before it is deflected and passed through the air inlet (m) into the material. This can be done segment by segment or over the entire dryer length, and it can also be combined with other locations of air introduction, for example with introduction of the air into the material lysis tunnel, as described in 585/12. In this type of heating, the correct inlet height of the hot air must be ensured, sufficiently high to heat as much of the sliding plate (i) as possible, not sufficiently deep for material deposits in the area where the material impacts the sliding plate (i) ignite. But air is not the only medium that heats the spin dryer from below can be. Fluids such as water and oil are also suitable for this purpose. Here, the cooling water of a Verbernungsmotors can be used, or the Abwaerme a water-cooled combustion chamber, which will be described below, or a sun-heated medium, or any otherwise for availing heat source. Again, this is segmented, or can be done over the entire length of the dryer.

Further, a filter device (s) in the drying chamber was selected therein, shown in the figure 4 in the form of pocket filters. What has not already been held back by gravity in the calming stretch (z) which can be expanded as desired is deposited here. The filter device can be supplemented by a slide plate (o), at the lower end of which a conveyor screw, or otherwise a suitable removal device, is attached. Finally, it should be mentioned that slip sheet (i), wave shell (j) and baffle (k) are subject to a certain wear, especially in sewage sludge and other materials loaded with inorganic materials, in particular with sand. This can be counteracted on the one hand with a suitable coating. On the other hand, there is also the possibility of doubling the elements mentioned, wherein the layer exposed to the material is replaced at regular intervals. For double, but also for individually guided elements there is the possibility not to firmly weld these elements, but by suitable holding devices only to put it, perhaps only slightly to fasten it, so that the elements can be easily removed and replaced. - The same applies to the spinning shaft whose ends, in the drying chamber, in each case before the bearings are designed so that the spinning shaft can be easily replaced, either by abutting each other bolted "plate", be it by another suitable device , In the patent application 259/12 it is described that for the start of the shaft after a blockage by the material, or in the event of an overcharge of the dryer, a second electric motor can be mounted in order to give the required extra boost for the start. But this can also be done simply by the Anbrinung a fixed, or removable mechanical device, for example, with a rotary key that rotates in one direction only, a correspondingly long lever and a matching end of the spinning shaft on which this can be applied. The drawing 5 shows a combustion chamber. The burner (p) is located in the lower part. The flame has enough space to burn free. The hot flue gases rise and mix with the fresh air that enters through the inlet (r) and leaves the combustion chamber through the air outlet (s) as a hot air / flue gas mixture. Other arrangements of firing, fresh air inlet and mixing of air and fuel gases are also conceivable. All embodiments are common in the invention that they. to be cooled with water, possibly with oil, or otherwise with a suitable gaseous, liquid or even solid medium (q). This makes it possible to make better use of the radiant heat of the burner (p) than if it were only isolated. A first possibility is to remove the heat via a heat exchanger in the area of the air inlet of the combustion chamber (r), by pre-heating the incoming air. If a countercurrent heat exchanger is used, higher temperatures result than with other heat exchanger configurations, which however are not excluded. If a configuration is selected in which no fresh air is added at all, the supply air of the burner can be heated. Another possibility is to use the heat from the combustion chamber cooling (q) to heat the walls of the spin dryer. It is also possible to install a heat exchanger also in the outlet area of the air (s), for example in order to use part of the heat energy in order to produce a steam engine or other power heat. Operate coupling machine. Thus, among other things, the energy for the movement of the spinning shaft, the fans, other consumers of the dryer, or even mechanical energy about the needs of the dryer itself can be obtained. With Stirling or other engines that require rather high temperatures, the corresponding heat exchanger will be located closer to the flame. The Abwaerme the combustion chamber can also be used for heating purposes outside the dryer, including in winter to heat the premises in which the dryer is. The drawing 6 represents a spark filter, which is especially necessary if solid fuels are burned. It consists of a cylindrical channel (t), in which the flue gases, or the flue gas / air mixture, is set in a rapid rotational movement / are. The rapid movement of the air does not create any build-up on the walls and the sparks are "blown out." The rotation and the speed can be assisted by another internal cylindrical device, here called the "soul". Furthermore, a suitable Lufteinfuehrung will support the rotational movement. In the present illustration, the air is introduced tangentially through two opposite inlet channels (v). This leads to an immediate turning movement in the whole channel, whereas at one inlet only it builds up slowly. The same device can also be used for the separation of dust particles, which are pressed by the rotational movement to the outside. For this purpose, at a suitable location, over a part, or over the entire length of the cylindrical channel (t), a dead-end is provided into which the dust particles are transported by the rotational movement of the air. If the entrance of this dead end is in the form of a "nose", the burden of conveying the air increases, but the degree of dust collection improves. This device can be integrated into the combustion chamber, or installed afterwards. Both the cylindrical channel (t) and the core (u) can be cooled by any medium, by any convenient method. It can be particularly interesting to design the cylindrical channel (t), the soul (u), or both, in the form of a coil.

A possible location for the combustion chamber, with or without spark filter, or for the dryer firing in general, is in drawing 4 with (aa) and is located in the holo behind the slide plate (i), so that this room is used and the entire system becomes even more compact. Here is also the possibility that the radiant heat of the burner, the slide plate (i) directly heated.

The combination of the combustion chamber - in the version with or without Frischluftzu- drove - with the spark filter, can serve as a device not only for heating with solid fuel from dryers, but also other devices. Any subsequent heat exchangers are less stressed by the dedusting of the flue gases. In the following, reference is made to drawings 7 to 13:

In February 2012, the same inventor presented under number 259/12 an optimization of centrifugal-wave dryers, which is characterized essentially by the fact that the spinning shaft is used along the direction of flow of the material, but the drying air introduced transversely to the direction of flow and through the dryer is passed through. This has the great advantage that the material receives freshly heated, unsaturated drying air at each point of its passage through the dryer. This is in contrast to conventional spin dryers, where the drying air is parallel to the material flow to be led. With certain materials, there is a risk that at the end of the passage, the now saturated air will return moisture to the material instead of drying it to completion. Or else, the drying process must be divided into several drying chambers, which must pass through the material, as shown for example in patent DE 10 2010 049 339 A1, but this means in comparison to the proposed solution, an extra effort in design and operation. In addition, the air is guided so that it is forced through the cloud of material through which deflectors, obstacles, etc. can be dispensed with. Another simplification. This document presents further possibilities for optimization and application of the same invention.

Drawing 7: Posing the material

Drawing 8: Posing the material with breakwaters

Drawing 9: Raising the material with air barrier

Drawing 10: Insertion and ejection of the material

Drawing 1 1: Raising with two spinning shafts

Drawing 12: raising with a bent trajectory

Drawing 13: Air inlet and outlet on the same side. The designation of the elements is the same in the drawings 7 to 13:

In the present variant, the spinning-shaft dryer is equipped with a single spinning shaft (a1), as in the drawings 7, 8, 9 and 10, as well as 12 and 13, but this does not exclude the execution with more than one spin shaft. In drawing 1 1, a variant is shown with two centrifugal shafts. A larger number of waves is also conceivable. There is also the possibility that one or more waves, the material from the bottom of the dryer raise, while one or more other waves are in the drying room and receive the material raised from the ground and throw further, or swirl. Furthermore, there is also a possibility of throwing the material from floor to floor, wherein each floor is formed a combination of spin-shafts (a1) and spin-wave shells (b1). If the blades are arranged offset on the spinning shaft, the material is thrown up turbulently and a mixture effect is created, which can be additionally reinforced by the geometry of the blades. This can be a desired effect during the drying process, but also opens up the possibility of using this device not only as a dryer, but simply as a material mixer.

As will be explained later in the description, it may also be desirable for the material to be thrown up in the same place as possible. In this case, the spinning shaft will be equipped with T-pieces, with the longest possible upper crossbar, or even with blades or crossbars, which extend over the entire length of the spinning shaft.

In the drawings 7, 8, 9 and 12, a spinning shaft is shown with only two rows of blades. But it can be more. As in drawing 13, there may be four rows of blades, or more. The larger the diameter of the axle and the more uniform the material is to be thrown, the more blade rows are used.

The shell in which the spinning shaft rotates (b1), as shown in the drawings 7, 8, 9, 12 and 13, is pulled up so that the throwing direction of the material is defined in a single, desired direction. This part of the spin-wave shell is called the material-throw baffle (c1). Different angles can be defined fixed or adjustable. As a result, on the one hand the space occupied by the material raised, reduced and on the other hand prevents that in the Area that can not be taken by the spin shaft, form undesirable deposits.

On the other side of the shaft, it is important that the sliding wall (d1) is at an angle such that the material passes sufficiently far down the axis of the spinning shaft so that the blades of the latter completely carry the material through the shell (Fig. b1) through and on the other side can raise again. Otherwise, there will be a jam and the device will no longer function optimally. This is particularly important if, as in FIGS. 11 and 12, but also in the drawings 7 to 8, the air inlet (j1) is located on the side of the sliding wall (d1).

In this constellation, the material thrown up, which falls onto the sliding wall (d1) inclined obliquely to the spinning shaft and thus being directed back to the spinning shaft, describes an ellipse (e1). The cavity (f1) in the interior of this ellipse can be desired as shown later and shown in the drawings 7, 8, 12 and 13.

However, where this cavity is not desired, it is possible to fill this room with material. For this purpose, as shown in Figures 8 and 9, elongate devices, in the form of round bars, flat plates, straight, angled or other shapes, are introduced into the material ellipse (e1) produced by the spin shaft (a1). These devices are called breakwaters (gl) because they actually make this visual impression. The wave is broken and the material is partially or completely redirected into the cavity (f1) inside the material ellipse (e1), so that it too can be filled with material and the space can be better utilized. This type of device can be made adjustable by hand or automatically. There are other reasons to provide analogous elements. In the drawing 6, for example, the shape of the material Elypse (e1) is influenced. In the case shown, the angle of the impact of the material on the sliding wall (d1) is also changed. Another reason may be to loosen damp or heavy material which is thrown up in even portions when it is evenly thrown up so that the corresponding contact surface is created here as well. In both cases, comb-type devices will be more likely to be used.

Finally, it should be mentioned that a wave breaking or material loosening device can also be performed in the form of another spin shaft.

You can operate this dryer as a through-dryer, in which the moist material is continuously filled and the dry material is removed continuously. Moving the material through the dryer uses the phenomenon that the material tends to equalize along the spin wave to a uniform level. If material is added in the drawing 10, left, at the material inlet (h1), at one end of the spinning shaft, the material already in the dryer automatically moves in the direction of the material removal (i1), at the other end of the spinning shaft (a1) , displace. The same applies on the other side, in the material removal (i1), at the other end of the spinning shaft (a1), in the reverse operation. If material is removed there, material automatically moves in, as the material tends to equalize to a uniform level. This allows the dryer to create a continuous movement of the material through the dryer. If a more uniform style of posing is chosen, the regularity of this movement is also supported. This type of movement of the material through the dryer is additionally associated with the advantage that the residence time of the material can be determined relatively accurately. This can be what is rather difficult with conventional centrifugal shaft dryers with parallel guidance of air and material. In order to set the dwell time, one can, as shown in drawing 10, the input (h1) and the discharge (i1) of the material provided with an adjustable mechanism, here shown with a feed screw. The auger can be mounted below or to the side, in the area of the skimmer shaft (b1), or in another suitable location. One of the other suitable locations is to attach the material removal screw to the rear wall of the dryer on the sliding wall (d1). In addition, other mechanisms than screw conveyors are conceivable. Mentioned as an example that the removal of material on the sliding wall can be done with a slider that is more or less open and thereby more or less material is thrown through this opening out of the dryer. Such a sliding device can also be mounted in other places, for example at the bottom of the dryer. The same applies to any other removal device.

There are also several options for automatically controlling this material throughput, two of which are described here. One is that material insertion and removal of material, taking into account the required residence time, are matched to each other, as required by the inlet and outlet humidities. If the moist material is twice as heavy as the dry one, then the material insertion (h1) is set to twice the amount per defined time unit than the material removal (i1) at the other end, which is also adjusted accordingly. The other possibility is to design the material insertion control technology to a certain wave load, so that always so much material is thrown in that this wave load is kept constant. The residence time can then be controlled solely by the removal of material (i1).

For very wet materials, for very long residence times, or for materials where the final moisture must be very accurately determined, you can see the flow split into several chambers. In extreme cases, helping only the portion drying, which is described later in the text.

The insertion of material can take place laterally or from above, theoretically even from below. The movement of the material can be supported by the inclination of the axis, fixed or adjustable.

Of course, this type of dryer can also be operated as a portion dryer. For this purpose, the material is introduced at a suitable point and removed after the defined drying time in a suitable manner. Insertion of material (h1) and -due (i1) can be arranged exactly the same as in continuous operation, possibly optimized by an adjustable tendency to dryness. Since the fastest possible filling and removal is advantageous in the case of portion drying, the material can be filled at several points, or even over the entire length of the axis. For removal, one of the sidewalls or floor can be opened, the whole dryer can be tilted, corresponding sliding doors or other devices used, or otherwise used in a manner that allows the dryer to be emptied as quickly as possible at a time. Another interesting option is to pneumatically suck the material out of the dryer. Not only, but especially in pneumatic conveying, it is also conceivable to divide the dryer by dividing walls into segments. Thus, a possible division of the portion-drying process can be bypassed on several dryer units, but of course also possible. Thus, whether in continuous or portion drying, the dryer may basically consist of a single continuous unit, a single unit divided by segments, a plurality of units, or a combination of these variants. There are several variants for introducing the air. The first is, as in the drawings 7, 8, 9, 11 and 12, to introduce the air on the side of the sliding wall (d). While the drawings 7 to 9 show an embodiment which is not suitable for all materials, or may need to be protected from clogging by a grid, the drawings 11 and 12 show an embodiment which is guaranteed to be free from clogging. It should be noted that the slide plate (d1) feeds the material at the correct angle of the spin shaft, as mentioned in the introduction, but that the underlying wall of the air inlet is steep enough that no material can accumulate and that this angle the material also smoothly the centrifugal shaft feeds. This means that the material comes to rest where it can be taken back by the blades of the spinning shaft (a1) and in no case impinges too close to the axis of the spinning shaft.

When introducing the air from the side of the slide plate (d1), it will make the same movement as the material. If the material is relatively coarse, the air in the material ellipse (e1) will remain in and exit at its tip. With finer materials, the air will emerge from the material ellipse (e1) relatively soon after the material throw baffle (d). Here, it may be useful, as shown in drawing 9, to supplement the interior of the dryer with an air baffle (m1) to increase the residence time of the air in the material. Also in the drawing 1 1, an analogous, the flow conditions adapted air baffle be useful, even if a variant is shown without such in the drawing. Such an air baffle can also be useful for the other subsequent air duct variants, or even further variants.

In this, but also in all other air guidance variants, it makes sense to provide a calming section (11), on which the flow velocity of the air is reduced and the gravitational force can deposit as much of the suspended matter contained in it as possible. In virtually all drawings such is shown. After the possibility to introduce the air on the side of the slide plate (d1), there is another, as shown in the drawing 13. Here, the air is blown in on the side of the material baffle (d). This creates a kind of countercurrent compared to the movement of the material. It is interesting to observe that the spinning shaft (a1) pulls at least part of the air through the material ellipse (e1) into the cavity (f1) located therein. This air must pass at least twice through the material ellipse (e1): once at entry, once at exit. If the air outlet on the same side is selected, there will automatically be a calming section (11) for the air before it exits (j1).

Finally, the possibility should be mentioned to introduce the air directly into the cavity (f1), from one or both sides. This differs from the principle of the air flow direction, which is always transverse to the flow direction, but the effect is very similar. The air enters the cavity (f1), has to pass through the material ellipse (e1), and the material also receives fresh, unsaturated air through the dryer at virtually any point. In addition, this solution is structurally the easiest to solve. The latter possibility opens up even more perspectives. In the cavity (f1) can also be fired directly into it, especially in fire-resistant materials, or very wet material, but not exclusively. The material supply can be controlled so that the material, despite maximum inlet temperatures of the flue gases, does not exceed certain maximum material temperatures. Depending on the material, the configuration of the impellers of the spinning shaft (a1) can be selected here so that the material is also mixed to a greater or lesser extent, so that there is nowhere too dry material that could ignite. As mentioned in the introduction, the material can be turbulent, uniform, or mixed. Patent Application 259/12 describes the possibility of having several air streams distributed in the same dryer, on several segments in the dryer, or on several dryers. Especially the variant, in which is fired directly into the material, offers itself to lead the dense and high-energy steam, which arises as a result of heat recovery and heat with the recovered heat to heat a second air stream, with another drying section, or another dryer unit can be operated. These can also be sequential to each other, wherein the material that was exposed directly to the fire, cooled in the subsequent segment and any sparks are definitely blown out. Of course, the ability to heat a second segment or dryer with the waste heat of a first one is not limited to the case of direct exposure of the material to the fire. On the other hand, the variant with direct exposure of the material to the fire is mentioned in particular in connection with problematic materials, such as, but not limited to sewage sludge, slaughterhouse waste and other animal by-products. The possible continuous filling and removal of material into such a device mentioned above in the text can be used not only for drying but also for gasifying material. A variant of this is briefly described, in which the material is gasified in countercurrent. At one, the "hot" end, is fired into the material, or it is added air and the material is burned at this end.On the other, the "cold" end, the material is introduced and by the described tendency of Material to be balanced along the spinning shaft (a1) is fed to the "hot" end and degassed on the way there.The most suitable, but not exclusive, operation is analogous to through-drying. tion of the air outlet adjusted accordingly. - By the way: even a dryer in countercurrent principle is so conceivable.

With regard to the features of the invention which are not explained in greater detail above, reference is expressly made to the claims and the drawings.

List of references a) discharge of sewage sludge from the centrifuge.

b) Zuführbehaelter the dryer

c) Foerdervorrichtung in case of overflow of the Zufuehrbehaelters. d) spin dryer

e) entry of sewage sludge into the dryer

f) spin shaft

g) Material removal

h) Material return

i) slide plate

j) shell

k) baffle

I) heating of i + j + k

m) air intake

n) filters

o) slide sheet dust

p) Burner

q) water jacket

r) air inlet combustion chamber

s) Air outlet combustion chamber

t) outer jacket spark filter

u) Soul spark filter

v) Air inlet (e) Spark filter

w) dead end for the dust

x) "nose" the dead end for the dust

y) air intake device

z) calming section

aa) Possible location for dryer firing a1) Spin shaft b1) Shell of the spin shaft c1) Material throw baffle d1) Sliding wall

e1) Material Elypse

f1) cavity

gl) Breakwater

h1) material inlet

i1) Material removal

j1) air

k1) air out

11) calming section for the air m1) air baffle

n1) material supply container

Claims

claims

1 . Apparatus for thermally treating a dampening substrate to increase the dry matter content of the dampening substrate, comprising at least one swirling shaft disposed in a housing having means disposed thereon for fragmentally conveying dampening substrate into a drying space of the device, the device comprising an inlet for dampening substrate and an outlet for at least Partially moisture-reduced substrate and the drying space has an inlet and an outlet for drying air and the drying space is designed for entry of heat energy, characterized in that the substrate outlet of the device for controlling the amount of present in the drying room, at least partially moisture-reduced substrate is formed.

2. Apparatus according to claim 1, characterized in that the device at the substrate outlet for controlling the amount of substrate a screw conveyor or a

Rotary valve has.

3. Apparatus according to claim 1 or 2, characterized by a provided at the inlet for moist substrate screw conveyor, the dampening substrate adjacent to the edge region of the drying space in the detection range of the spinning shaft provides.

4. Device according to one of the preceding claims, characterized in that the centrifugal shaft is provided along its longitudinal extent with means for turbulent and / or substantially homogeneous conveying of moisturizing substrate and / or substrate in the drying space.

5. Device according to one of the preceding claims, characterized in that the spinning shaft is provided with blades in triangular shape and / or strips, wherein blades with different angles of attack are providable.

6. Device according to one of the preceding claims, characterized by a screw arranged in the housing for returning substrate in a region of the spinning shaft, in which the substrate mixes with moist substrate largely lump-free or means for sucking substrate from the drying room and return to another Place the drying room for a largely lump-free mixture with a moist substrate.

7. Device according to one of the preceding claims, characterized in that the means provided on the spinning shaft means for forming an elliptical trajectory of the conveyed into the drying space substrate and / or dampening substrate are formed.

8. Device according to one of the preceding claims, characterized in that the spinning shaft is arranged in the lower region of a formed of a substantially rectilinear slide plate, a curved formed wave shell and a Substratleitblech receptacle for wet substrate and / or substrate and arranged on the spin shaft Extending radially in the direction of the shaft shell.

9. Device according to one of the preceding claims, characterized in that heat in the drying chamber by heat application of a wet subtrate and / or substrate leading recording and / or heat application of along the recording in the wet substrate and / or substrate guided track tion air and / or heat absorption of existing in the drying space moist substrate and / or substrate and / or drying air can be introduced.

10. Device according to one of the preceding claims, characterized by a NEN heat exchanger for recovering heat from the discharged from the device moist drying air.

1 1. A process for the thermal treatment of a dampening substrate for increasing the dry matter content of the dampening substrate by means of at least one arranged in a drying space spin shaft having means for fragmented conveying supplied from the drying space moist substrate in the drying space in which is provided for receiving moisture from the dampening substrate drying air and Substrate of lower moisture content than the supplied moist substrate is taken from the drying space via an outlet, characterized in that moist substrate is transported into the drying space in which substrate is lower in moisture content than the dampening substrate and the outlet for changing the continuous or discontinuous removable discharge amount for controlling the present in the drying space substrate with lower moisture content is controlled.

12. The method of claim 1 1, characterized in that the spinning shaft for the mixing of the wet substrate with the substrate is rotationally actuated and the supply of wet substrate depending on the temperature measured in at least one location in the drying chamber and / or at least one location measured NEN moisture value and / or the driving power required for the rotational operation of the spinning shaft is controlled.

13. The method of claim 1 1 or 12, characterized in that the drying chamber heat in the form of waste heat of an internal combustion engine and / or heat of the flue gas is supplied to a furnace, which is treated prior to introduction into the drying chamber by means of a spark filter and a Staubpartikelabscheiders ,

14. The method according to any one of claims 1 1 to 13, characterized in that the moist substrate before the thermal treatment has a dry matter content of preferably at least 50%.

15. Use of the method according to any one of claims 1 1 to 14 for the thermal treatment of sewage sludge or digestate or slurry or thermal drying treatment of provided with dry matter solutions and / or suspensions for obtaining powdered dry matter.