DE202018101574U1 - Standing fermenter - Google Patents

Abstract

Standing fermenter with a fermenter interior (1), a fermenter bottom (2) and a, the fermenter interior (1) delimiting fermenter wall (3), wherein the fermenter has an agitator and the agitator at least one outside of the fermenter interior (1) arranged drive unit (4 ), a fermenter shaft support (5) arranged in the fermenter interior (1), a fermenter-side support (6) arranged at the fermenter interior (1), fermenter-side stirring shaft bearing (7) supporting the fermenter bottom (2), and at least one Stirring shaft (8) with at least one, on the agitator shaft (8) fixed agitator blade (9), wherein in the fermenter (3) a Fermenterwandungsdurchführung is provided and the agitator shaft in the fermenter wall bushing passage penetrates the fermenter wall (3), wherein in the Fermenterwandungsdurchführung a the fermenter interior (1) liquid-tight and gas-tight de seal is arranged, characterized in that at least one, the wall-side stirrer shaft bearing (5) on the fermenter bottom (2) supporting, in the fermenter interior (1) arranged, wall-side support (10) is provided, the fermenterseitige support (6) and the wall side Support (10) are designed such that the static and dynamic loads caused by the agitator are substantially completely introduced into the fermenter bottom (2).

Description

Technical area

The invention relates to a standing arranged fermenter with a stirrer for the input of mechanical energy.

State of the art

Biogas plants produce methane through a microbial decomposition process of organic substances. The biogas is produced in a multi-stage process, the fermentation or digestion, by the activity of anaerobic microorganisms, i. in the absence of air. The type of organisms is essentially determined by the specific process parameters such as temperature, substrate, pH, etc. As a result, an adaptation of the microorganisms to the respective substrate is achieved, which makes it possible to degrade a variety of organic materials by fermentation.

Organic material has a high molecular structure from a chemical point of view, which is degraded in the individual process steps of a biogas plant by metabolic activity of the microorganisms to low molecular weight building blocks. In addition to biogas, which consists essentially of methane and carbon dioxide, remains in the process chain as fermentation residue a mixture of water, undegraded organic material and inorganic constituents. Degraded are usually strong ligninhaltige, woody materials and cellulosic substances. Inorganic constituents are minerals in the form of sand and stones, but also crystallized salts.

Central components of a biogas plant are the fermenters (fermentation tanks, fermentors, reactors), in which the primary biological processes take place. Concrete or steel plates (enamelled, coated or made of stainless steel) are usually used as materials for the construction of the fermenters. The microbial degradation processes taking place in a biogas plant are heavily dependent on the fermenter temperature. For this reason, the reactors are usually thermally insulated and equipped with a heater (external heat exchangers, heating coils on the inner wall, heated agitators or underfloor heating).

Since it can come in the course of up to three weeks of fermentation to segregation of the substrate, the material present in the fermenter is moved. The unwanted demixing would lead to the formation of high-solids floating and sinking layers, which hinder the mass transport in the reactor as a result. The reactor is usually equipped with a feed for semi-liquid to liquid materials and a feed screw for solid materials. Frequently, fermenters are equipped with devices for discharging the non-fermentable, settling in the bottom region organic and inorganic constituents. The task of discharging the fermented substances from the reactor is carried out by a riser submerged in the fermentate, which is designed as an overflow into a further reactor or into a substrate storage. The biogas produced is taken from a so-called gas dome and sent for recovery.

From these general remarks on biogas plants, an impression of the conditions prevailing in fermenters can be obtained: In fermenters partially very viscous dispersions with a high solids content by agitators or similar devices are at least temporarily moved vigorously. Individual particles, e.g. Whole sugar beets measure up to 25 cm in diameter. It can be assumed that at least temporarily stable floating layers in large coherent mats are pulled by the agitator through the fermenter. These factors lead to a high mechanical load of all components installed in the fermenter.

The movement introduced by the agitators ensures a thermal and material balance in the fermenter. Thus, freshly introduced substrate is decomposed significantly faster by mixing with bacteria-rich, angegorenem substrate than without this inoculation. The thermal balance caused by the agitators is essential for establishing favorable living conditions for the bacteria throughout the fermenter, whereby an optimal fermentation process can be achieved.

The increasing use of renewable raw materials (NaWaRo) as well as correspondingly high-energy substitution substrates in biogas plants and the associated trend towards highly solids-containing substrates place changed demands on the stirring technology used in the fermenters. The agitators are in the case of high-solids substrates, which have dry matter contents of more than 8%, exposed to special loads. Reasons for this are the high viscosity of the media and the obstruction of the resulting biogas due to this high viscosity. The substrate changes from a thin, coarse matrix containing solid particles in agricultural biogas plants via a relatively heterogeneous dispersion with limited mobility in mixed agricultural / NaWaRo plants to foamy, homogeneous slurry substrates in pure NaWaRo plants.

The fermenters used in connection with biogas plants are often standing fermenters with a radially symmetrical cross-section. The substrate in these round containers is mixed in part by means of agitators rotating around the main axis of the cylindrical container. Such agitators transmit high torques due to the relatively long lever. All components must be designed to be robust. The relative stirring blade speeds of such agitators are usually not sufficient to cause a growth of thick biofilms preventing mechanical overflow of the stirring blade. As a result, stable mat-like coverings grow on the stirring blades. The force to be introduced and thus the load of the force-transmitting components and the drive increases with the growth. Increased wear, increased energy requirements and increased maintenance are the result.

In round fermenters also submersible mixers are used. The main problems in this context are the permanent encapsulation of the drive against the substrate as well as the cavitation associated with the usually small rotor dimensions. So only relatively little mechanical energy can be entered per submersible mixer. Submersible mixers are in biogas plants at best as additional agitator or for the interconnection of several submersible mixers.

As an alternative to the mentioned agitators, so-called paddle stirrers are frequently used in standing round fermenters. The axis of these paddle stirrers is usually aligned parallel to the fermenter bottom. The agitator is supported on the one hand via a corresponding load-bearing construction in the fermenter interior on the fermenter bottom and on the other hand on the fermenter wall. In the vertical projection from above, the stirring shaft segments the fermenter circuit. The stirring shaft usually carries a plurality of stirring blades and causes effective mixing of the substrate in the round container. Such an agitator for the entry of mechanical energy in a standing arranged fermenter is for example from DE 20 2006 004 982 U1 known.

The paddle stirrers are usually mounted in pressure or radial bearings which are rigidly connected to the shaft and the fermenter wall or supporting structure. This rigid connection leads to considerable problems during installation and operation. When installing the agitators slight deviations from the planned dimensions can no longer be compensated. The assembly of the rigidly mounted agitators is time-consuming precision work. Minimal deviations in the core bore for receiving the wall-side bearing lead to tensions in the shaft or make elaborate rework required. In operation, when stirring the viscous mass, heavy loads are produced which are transmitted completely via the rigidly fixed shaft to the rigid bearings and ultimately to the bearing receptacles. High bearing wear and material fatigue are the result.

The introduction of mechanical energy in standing arranged fermenter of biogas plants is currently unsatisfactory solved.

Presentation of the invention

The invention, as characterized in the claims, the object is based on providing a vertically arranged fermenter with stirrer, which allows for relatively low maintenance effort effective introduction of mechanical energy into the substrate present in the fermenter.

This object is achieved by the vertically arranged fermenter according to independent claim 1. Further advantageous details, aspects and embodiments of the invention will become apparent from the dependent claims, the description and the figures.

The present invention provides a standing fermenter with a fermenter interior, a fermenter bottom and a fermenter wall delimiting the fermenter wall. The fermenter has an agitator, wherein the agitator at least one arranged outside the fermenter interior drive unit, arranged in the fermenter interior, wall-side stirring shaft bearing, a at least one, arranged in the fermenter interior, fermenterseitige support itself on the fermenter bottom abstützendes, fermenterseitiges Rührwellenlager, and at least one stirring shaft at least one, attached to the stirring shaft agitator blade. In the Fermenterwandung a Fermenterwandungsdurchführung is provided and the agitator shaft penetrates in the region of this Fermenterwandungsdurchführung the Fermenterwandung. In the region of the fermenter wall bushing, a fermenter interior is arranged in a liquid-tight and gas-tight sealing. According to the invention, at least one, the wall-side stirrer shaft bearing on the fermenter bottom supporting, arranged in the fermenter interior wall-side support provided, the fermenterseitige support and the wall-side support are designed such that the static and dynamic loads caused by the agitator are substantially completely introduced into the fermenter bottom ,

The present invention is based on the idea not to initiate as usual the moments and loads caused by the installed outside the fermenter motor-gear unit moments in the container or via a provided outside the fermenter support structure in the ground, but on a provided in the fermenter interior to transfer additional support of the wall-side stirrer shaft bearing to the bottom of the fermenter. Essentially all static and dynamic loads of the drive unit provided outside the fermenter are transferred constructively through the fermenter wall to the supports which are located in the interior of the fermenter and are introduced from there into the fermentor floor.

By this measure, all types of known from the prior art, provided outside the fermenter support structures for supporting the engine-transmission unit can be avoided. There is no need for a support on an additional bottom plate concreted outside the fermenter, nor is it necessary to provide a construction supported on the fermenter wall. This avoids all risks that can result from indefinable settlements of externally constructed foundations. This is in particular a high bearing wear and fatigue, which can be caused by minimal subsidence of the external supporting structure of the drive unit supporting foundation. In the case of the well-known from the prior art, supported on the Fermenterwandung constructions caused by the motor-gear unit moments and loads are intentionally introduced into the container, which must already be considered in the dimensioning of the wall. In addition, occur during initiation of the above loads in the fermenter wall at longer operating times always damage due to fatigue. The present invention effectively and reliably prevents this type of damage. It is achieved an overall extremely stable overall construction, in which even when starting and stopping the agitator no strong, unwanted movements of the agitator occur, which could lead to damage, especially the fermenter wall.

Since the agitator in the fermenter interior, but the drive unit is located outside the fermenter, the agitator shaft must penetrate the fermenter wall. For this purpose, a Fermenterwandungsdurchführung, so an opening is provided in the fermenter wall. In the region of this fermenter wall bushing a seal is arranged, which closes the fermenter interior liquid-tight and gas-tight. The seal is thus designed so that neither biogas nor fermentation substrate can escape from the fermenter interior, which is why the entire system can be operated with varying substrate levels in the fermenter.

The fact that, according to the invention, the fermenter-side support and the wall-side support essentially completely introduce the static and dynamic loads caused by the agitator into the fermenter bottom means at the same time that the agitator shaft and also the entire agitator construction penetrates the fermenter wall in the area of the fermenter wall bushing, without interfering with it this in a force-transmitting contact. It is obvious to the person skilled in the art that, due to the impermeability requirement, there must be some contact between the individual components. However, this contact is so pronounced that no transfer of any forces on the Fermenterwandung is possible.

By means of the wall-side support according to the invention arranged in the fermenter interior, it becomes possible to retrofit existing fermenters with an agitator without the need for an external support for receiving the torque caused by the external motor-gear unit. In particular, it is not necessary to subsequently concretize an external floor slab on which a support structure could be placed. Thus, it is also prevented that forces are introduced into the Fermenterwandung by a subsequent, undefined setting this subsequently concreted bottom plate, which lead to damage and increased repair costs. This applies both to static forces and to dynamic forces, since a shift in the removal of the torque caused by the external motor-gear unit can occur due to unequal settlement of the external foundation.

Rather, the already existing bottom plate of the fermenter can be used by setting up the wall-side support in the fermenter interior. So there are no additional earthworks and / or concrete construction measures required. In addition, the installation of the agitator is possible year-round and weather-independent. Finally, due to the fact that the support is in the fermenter interior, no additional corrosion protection for the support is required. However, the engine-transmission unit is still, as known from the prior art, outside the fermenter wall and thus remains freely accessible even during operation of the biogas plant for maintenance and repair work.

Preferably, the stirring shaft provided in the fermenter extends parallel to the fermenter bottom. An agitator equipped with a stirrer shaft running parallel to the fermenter tray carries a sufficient amount of mechanical energy into the standing fermenter. In particular, even highly viscous substrates can be sufficiently stirred. Due to the relatively high overflow velocities of the substrate on the stirring blades, the agitators remain so far free from fouling by thick biofilms that their function as a stirrer is not affected even with prolonged use. The agitator alone or in conjunction with other stirring or mixing devices for effective mixing of the substrate in Rundfermentern. In particular, the training is effectively counteracted the operation disturbing, stable swimming and sinking layers. In addition, the release of the substrate in the form of bubbles bound biogas is supported. The advantages mentioned are achieved by the agitator with a simultaneously relatively low stirring energy requirement.

Very particular advantages brings the present invention in fermenters in which only very little or no forces can be introduced into the fermenter wall for static reasons. This is the case especially in the case of fermenter walls made of metal plates, in particular steel plates, and fermenter walls made of precast concrete components. Generally one speaks here of "segment containers". In the case of in-situ concrete fermenters, the transfer of loads, especially torques, into the fermenter wall is not a dramatic problem. In-situ concrete fermenters are typically built so sturdy and thick-walled that external structures are used to remove the loads caused by the drive unit be relatively safe to support the fermenter wall. However, this is not the case with segmented containers. Here, it can easily lead to fatigue and damage in long-term operation, especially when dynamically occurring loads, as they occur in the case of startup and shutdown of the agitator, are introduced into the wall. This is prevented by the derivation of these loads according to the invention via the additional support provided in the fermenter interior of the wall-side stirring shaft bearing in the fermenter bottom.

According to a particularly preferred embodiment of the present invention, the fermenter arranged vertically is therefore a fermenter made of prefabricated concrete components or of metal, in particular of steel, particularly preferably of metal plates, in particular steel plates. The term "fermenter made of steel" is to be understood as meaning a fermenter wall made of steel. This wall is set in the usual way on an in-situ concrete slab as a bottom plate. Of course, it is clear to those skilled in the art that the Fermenterwandung is not 100% completely made of steel. Rather, for technical reasons, such as due to cable glands, viewing windows, engagement flaps or similar. also the use of other materials required. So what is meant is a Fermenterwandung, which is made for the most part of metal or in particular of steel. Enamelled steel, coated steel or stainless steel, in particular enamelled steel plates, coated steel plates or stainless steel plates, is particularly preferably used.

Due to the above-described, essentially force transmission-free implementation of the stirring shaft through the Fermenterwandung each load transfer is prevented in the steel wall. The transmission of the torque of the agitator is therefore not straight as known from the prior art via a torque arm in the fermenter, but on the arranged in the fermenter interior wall-side and fermenter side support structure in the fermenter bottom.

According to a further, particularly preferred embodiment of the present invention, both the fermenter-side support and the wall-side support are designed to be height-variable. Particularly preferably, the fermenter-side support and the wall-side support are designed to be variable in height such that the stirring shaft can be arranged between 2.5 m and 5 m above the fermenter bottom. The installation height of the stirrer shaft is thus variably adjustable within a certain range and can be fixed on site. By this customizable height of the agitator accurate positioning of the Fermenterwandungsdurchführung is not required because any deviations can be compensated agitator side. Concrete variants for the height adjustment of the supports, such as telescopically extendable supports are known in the art.

Particularly preferably, the Fermenterwandungsdurchführung is equipped with a mounted on both sides of the Fermenterwandung Dichtflanschrahmen. As a result, the Fermenterwandungsdurchführung and the Fermenterwandung breaking agitator shaft can be particularly well and easily sealed, thus preventing the escape of biogas or fermentation substrate from the fermenter interior.

The sealing of the stirrer shaft can be advantageously carried out by means of multiple seal, as in particular in connection with Ortbetonfermentern known from the prior art. Particularly preferably, the seal comprises a tube fixed to the fermenter wall, the tube enclosing the stirring shaft but not being in direct contact with the stirring shaft. Particularly preferably, the tube is made of metal. Since the pipe is not in direct contact with the stirrer shaft, no relevant power transmission can occur.

Advantageously, the seal closing off the fermenter interior comprises a sealing ring arranged around the stirring shaft, which is particularly preferably made of polyamide. Through the interaction of sealing ring and tube a particularly stable, stable and secure sealing of the fermenter interior is achieved. As a particularly advantageous embodiments have been found in which the stirring shaft enclosing tube and the sealing ring are mutually formed positively.

The vertically arranged fermenter preferably has an agitator with a stirring shaft to which a plurality of stirring blades are attached, in particular two, three, four, five, six or more stirring blades. The stirring blades are preferably offset along the Rührwellenachse offset radially to the outside pointing to the agitator shaft. Particular preference is given to embodiments according to which the stirring blades are fastened to the stirring shaft at different circumferential angles. The term "circumferential angle" designates the angle which a stirring blade and any desired radially extending from the agitator shaft to the outside reference axis to each other. Particularly preferably, the individual stirring blades are offset by equal fractions of 360 ° of the circumferential angle to each other attached to the agitator shaft. If, for example, four stirring blades are attached to a stirring shaft, then adjacent stirring blades each enclose an angle of 90 ° to one another. In the case of five stirring blades, the angle is 72 °.

According to a further preferred embodiment of the present invention, the stirring blades each comprise two side parts and at least one bridge profile, wherein the two side parts are interconnected by the bridge profile. Preferably, the side parts of the stirring blades are perpendicular from the stirring shaft. By such a construction, a particularly good and effective mixing of the fermenter substrate is achieved at the same time relatively low energy consumption. Particularly advantageous conditions arise when the two side parts of a stirring blade are mounted in different circumferential angles on the agitator shaft. As a result, it is ensured that the bridging profiles that carry out the stirring energy run obliquely to the stirrer shaft. Particularly preferably, the two side parts of a stirring blade are attached to the stirrer shaft in circumferential angles differing by about 15 °. It sets a particularly good and energy-efficient mixing of the substrate.

According to a particularly preferred embodiment, the fermenter has a plurality of agitators. Depending on the size of the fermenter and the amount of substrate to be moved, the fermenter can advantageously have two, three, four, five, six or even more agitators. Particularly preferably, the stirrer shafts of the stirrers are mounted at different distances from the fermenter bottom.

If two stirrers are installed in the fermenter, the two stirrer shafts of the stirrers are preferably mounted at different distances from the bottom of the fermenter. Particularly preferably, the distance of the first stirring shaft from the bottom of the fermenter is about twice the distance of the second stirring shaft from the bottom of the fermenter. According to this embodiment, the two agitators are thus located at opposite positions in the fermenter, so they are offset by 180 ° to each other. By such an arrangement a uniform distribution of the introduced mechanical energy over the entire fermenter volume is achieved. Also, this goal is the mounting of the two agitators at different heights above the fermenter bottom. The agitators are constructed in mirror image and are driven in opposite directions. The upper agitator is mounted in such a way that the stirring blades break through the upper substrate level in any case. The agitator shaft of the lower agitator is preferably at a height level with the lowest position of the agitator blades of the upper agitator. This results in three stirring zones in the stirring operation, wherein the middle stirring zone rotates in the opposite direction to the upper and lower zones.

If three stirrers are installed in a fermenter, the axes of the stirrer shafts preferably enclose an angle of 120 ° to one another. According to a particularly preferred embodiment, the three stirrer shafts of the agitators are mounted at different distances from the bottom of the fermenter. Particularly preferably, the distance of the first stirring shaft from the bottom of the fermenter is about 1.5 times the distance of the second stirring shaft from the bottom of the fermenter and about three times the distance of the third stirring shaft from the bottom of the fermenter. By such an arrangement a uniform distribution of the introduced mechanical energy over the entire fermenter volume is achieved. As already described for the case of two agitators, the upper agitator is mounted in such a way that the agitator blades in any case the upper substrate level break through. The agitator shaft of the center agitator is preferably at a height level with the lowest position of the agitator blades of the upper agitator, while the agitator shaft of the lower agitator is preferably at a height level with the lowest position of the stirring blades of the center agitator. This results in stirring again three stirring zones, wherein the middle stirring zone rotates in the opposite direction to the upper and lower zones.

If four stirrers are installed in a fermenter, the axes of the stirrer shafts preferably enclose an angle of 90 ° to one another. According to a particularly preferred embodiment, the four stirrer shafts of the stirrers are mounted at different distances from the bottom of the fermenter. Particularly preferably, the distance of the first stirring shaft from the bottom of the fermenter is about 4/3 of the distance of the second stirring shaft from the bottom of the fermenter, about twice the distance of the third stirring shaft from the bottom of the fermenter and about four times the distance of the fourth stirring shaft from the bottom of the fermenter fermenter. By such an arrangement in turn the most uniform possible distribution of the introduced mechanical energy over the entire fermenter volume is achieved. As already described for the case of two and three agitators, the upper (first) agitator is mounted so that the agitator blades break through the upper substrate level in any case. The agitator shaft of the second agitator is preferably at a height level with the lowest position of the agitator blades of the upper agitator, while the agitator shaft of the third agitator is preferably at a height level with the lowest position of the agitator blades of the second agitator and the agitator shaft of the fourth (lower ) Agitator preferably located at a height level with the lowest position of the stirring blades of the third agitator. This results in stirring again three stirring zones, wherein the middle stirring zone rotates in the opposite direction to the upper and lower zones.

It is understood that in even larger volume fermenters in the manner described five, six, seven, eight or even more stirrers can be installed.

To ensure stable fermentation conditions, a radial flow of the substrate along the fermenter wall is desired. In the stirring blade arrangement shown, the substrate moving from the outer stirring blade adjacent to the fermenter wall has to cover a longer distance around the main fermenter axis for a complete circulation than the substrate moved by the stirring blades located further inside the fermenter. At higher speeds of the agitator, there is an unsatisfactory implementation of the introduced mechanical energy in the radial flow of the substrate, in particular in the case of the stirring blades located further inside the fermenter. If, on the other hand, very low speeds are used, an approximately ideal radial movement of the substrate occurs, in particular in the case of the agitator blades mounted in the vicinity of the fermenter wall, but an unsatisfactory entry of mechanical energy is also present in this case because due to the low rotational speeds Total amount of applied mechanical energy is too low.

In order to fulfill these two opposing conditions as well as possible, the length of the agitator shaft can be adapted to the typical rotational speeds of the agitator in standing fermenters. This is achieved particularly well if the length of the stirrer shaft is at most 75% of the fermenter radius. More preferably, the length of the agitator shaft is at most 66% of the fermenter radius, and most preferably the length of the agitator shaft is at most 50% of the fermenter radius.

Of course, the stirring shaft must have a certain minimum length, since it carries one or more stirring blades. The length of the stirring shaft is therefore preferably at least 25% of the fermenter radius. Particularly preferably, the length of the stirrer shaft is at least 33% of the fermenter radius and very particularly preferably the length of the stirrer shaft is at least 50% of the fermenter radius.

According to a particularly preferred embodiment of the present invention, the length of the stirring shaft is in the range of half the radius of the round fermenter. At this stirring wavelength, the difference in the paddle-specific substrate circulation paths on the one hand is relatively low, on the other hand, sufficient mechanical energy can be entered at typical rotational speeds of about 12 rpm.

list of figures

• 1 eine Ausführungsform eines erfindungsgemäßen Fermenters in der senkrechten Projektion von der Seite, wobei nur ein Teil eines Rundfermenters dargestellt ist;
• 2 eine Ausführungsform eines erfindungsgemäßen Fermenters in der senkrechten Projektion von oben, wobei nur ein Teil eines Rundfermenters dargestellt ist;
• 3 eine Ausführungsform eines erfindungsgemäßen Fermenters in der senkrechten Projektion von der Seite, wobei ein Fermenter mit zwei Rührwerken dargestellt ist.

To illustrate the invention and to illustrate its advantages, embodiments are given below. These embodiments will be explained in more detail in connection with the drawings. It goes without saying that these details are not intended to limit the invention. Show it

• 1 an embodiment of a fermenter according to the invention in the vertical projection from the side, wherein only a part of a Rundfermenters is shown;
• 2 an embodiment of a fermenter according to the invention in the vertical Projection from above, showing only part of a round fermenter;
• 3 an embodiment of a fermenter according to the invention in the vertical projection from the side, wherein a fermenter is shown with two agitators.

Ways to carry out the invention

The in the 1 and 2 schematically illustrated fermenter has a fermenter interior 1 with a fermenter bottom 2 and a, the fermenter interior 1 limiting fermenter wall 3 on. The fermenter wall 3 is essentially made of steel. The agitator for introducing mechanical energy into the standing fermenter comprises one outside the fermenter interior 1 , adjacent to the fermenter wall 3 , arranged drive unit 4 , one in the fermenter interior 1 , adjacent to the fermenter wall 3 arranged, wall-side stirrer shaft bearing 5 , one over three, in the fermenter interior 1 arranged fermenter-side supports 6 at the bottom of the fermenter 2 supporting, fermenter-side stirrer shaft bearing 7 and a stirring shaft 8th , The stirring shaft 8th runs parallel to the fermenter bottom 2 the standing Rundfermenters from the outside through the Fermenterwandung 3 in the direction of the main axis of the fermenter.

In the fermenter wall 3 a liquid-tight and gastight Fermenterwandungsdurchführung is provided, wherein the agitator shaft 8th in the area of the fermenter wall bushing, the fermenter wall 3 penetrates. The stirring shaft 8th is by means of the outside of the fermenter wall 3 with the stirrer shaft 8th connected drive unit 4 emotional. On the stirrer shaft 8th There are four stirring blades pointing radially away from the shaft 9 ,

With the stirring blades 9 these are two on the stirrer shaft 8th fortified, standing side panels 11 that have four bridge profiles 12 connected to each other. The side parts 11 are made of sheet metal and have a thickness of up to one centimeter and more. The two standing side parts 11 can be rotated on the agitator shaft by several degrees against each other, so that the stirring energy entering bridge elements 12 run obliquely to the stirrer shaft. At the stirrer shaft 8th are four stirring blades 9 mounted with an offset of 90 °. The stirring shaft 8th is in the fermenter-side stirring shaft bearing 7 and in the wall shaft bearing 5 rotatably mounted.

The fermenter-side stirring shaft bearing 7 is supported by three height-adjustable supports 6 at the bottom of the fermenter 2 from. Also the wall-side stirring shaft bearing 5 supports over three, in the fermenter interior 1 arranged, height-adjustable, wall-side supports 10 at the bottom of the fermenter 2 from. By the fermenter side supports 6 and the wall supports 10 The static and dynamic loads caused by the agitator are essentially completely transferred to the fermenter bottom 2 initiated.

The in the 1 and 2 schematically shown round fermenter is equipped with a stirrer. In general, round fermenters with a diameter of up to 15.9 m are preferably equipped with a stirrer. The agitator is mounted so that the stirring blades break through the upper substrate level.

Round fermenters with a diameter of 16 m to 21.9 m are preferably equipped with two agitators. The two agitators are located at opposite positions (180 ° offset) in the fermenter. The two stirrers are mounted at different heights. The stirrers are constructed in mirror image and are driven in opposite directions. The upper agitator becomes, as in 3 shown, mounted so that the stirring blades the upper substrate level 13 break through. The agitator shaft of the lower agitator is preferably at a height level with the lowest position of the agitator blades of the upper agitator. Stirring operation produces 3 stirring zones, with the middle stirring zone rotating in the opposite direction to the upper and lower zones.

As in 3 The fermenter-side stirring shaft bearings are supported 7 Both agitators each have three supports 6 at the bottom of the fermenter 2 from. Also the wall-side stirrer shaft bearings 5 The two agitators are each supported by three, in the fermenter interior 1 arranged, wall-side supports 10 at the bottom of the fermenter 2 from. By the fermenter side supports 6 and the wall supports 10 The static and dynamic loads caused by the two agitators are essentially completely in the fermenter bottom 2 initiated.

Round fermenters with a diameter of 22 m or larger are preferably equipped with three or more agitators. The three agitators are evenly distributed on the fermenter wall (120 ° offset) and mounted at different heights. The upper agitator is mounted in such a way that the stirring blades break through the upper substrate level in any case. The agitator shaft of the middle agitator is preferably at a height level with the lowest position of the agitator blades of the upper agitator. The same applies to the height difference between the lower and middle agitator. The distance of the upper stirrer shaft from the bottom of the fermenter is thus about 1.5 times the distance of the middle stirrer shaft from the bottom of the fermenter and about three times the distance the lower stirrer shaft from the bottom of the fermenter. In the stirring operation, in turn, 3 stirring zones are formed, with the middle stirring zone rotating in the opposite direction to the upper and lower zones.

LIST OF REFERENCE NUMBERS

1

Fermenter interior

2

bottom of the fermenter

3

Fermenterwandung

4

drive unit

5

wall-side stirring shaft bearing

6

fermenter-side support

7

fermenter-side stirring shaft bearing

8th

agitator shaft

9

stirring blade

10

wall support

11

side panels

12

bridge profile

13

substrate level

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 202006004982 U1 [0011]

Claims (12)

Standing fermenter with a fermenter interior (1), a fermenter bottom (2) and a, the fermenter interior (1) delimiting fermenter wall (3), wherein the fermenter has an agitator and the agitator at least one outside of the fermenter interior (1) arranged drive unit (4 ), a fermenter shaft support (5) arranged in the fermenter interior (1), a fermenter-side support (6) arranged at the fermenter interior (1), fermenter-side stirring shaft bearing (7) supporting the fermenter bottom (2), and at least one Stirring shaft (8) with at least one, on the agitator shaft (8) fixed agitator blade (9), wherein in the fermenter (3) a Fermenterwandungsdurchführung is provided and the agitator shaft in the fermenter wall bushing passage penetrates the fermenter wall (3), wherein in the Fermenterwandungsdurchführung a the fermenter interior (1) liquid-tight and gas-tight de seal is arranged, characterized in that at least one, the wall-side stirrer shaft bearing (5) on the fermenter bottom (2) supporting, in the fermenter interior (1) arranged, wall-side support (10) is provided, the fermenterseitige support (6) and the wall side Support (10) are designed such that the static and dynamic loads caused by the agitator are substantially completely introduced into the fermenter bottom (2). Fermenter after Claim 1 , characterized in that the fermenter wall (3) is made of prefabricated concrete components or of metal, in particular of steel, particularly preferably of metal plates, in particular steel plates. Fermenter after Claim 1 or 2 , characterized in that the fermenter-side support (6) and the wall-side support (10) are height-adjustable. Fermenter after Claim 3 , characterized in that the fermenter-side support (6) and the wall-side support (10) are designed variable in height such that the stirring shaft (8) between 2.5 m and 5 m above the fermenter bottom (2) can be arranged. Fermenter according to one of the preceding claims, characterized in that the Fermenterwandungsdurchführung is equipped with a both sides of the Fermenterwandung (3) mounted sealing flange. Fermenter according to one of the preceding claims, characterized in that the fermenter interior (1) final seal comprises a surrounding the agitator shaft (8) arranged sealing ring, wherein the sealing ring is preferably made of polyamide. A fermenter according to at least one of the preceding claims, characterized in that the seal comprises a tube fixed to the fermenter wall (3), the tube enclosing the stirring shaft (8) but not in direct contact with the stirring shaft (8) Pipe preferably made of metal. Fermenter after Claim 7 , characterized in that the the stirring shaft (8) enclosing tube and the sealing ring are mutually positively formed. Fermenter according to one of the preceding claims, characterized in that two, three or four stirring blades (9) are fastened to the agitator shaft (8), wherein the agitating blades (9) offset from each other along the agitator shaft axis point radially outward on the agitator shaft (8). are fixed, wherein the stirring blades (9) are preferably attached to the stirring shaft (8) in different circumferential angles, and the individual stirring blades (9) are particularly preferably offset by equal fractions of 360 ° of the circumferential angle to each other on the agitator shaft (8). Fermenter according to one of the preceding claims, characterized in that the stirring blades (9) each comprise two side parts (11) and at least one bridge profile (12), wherein the two side parts (11) are interconnected by the bridge profile (12), wherein the Side parts (11) of the stirring blades (9) preferably project perpendicularly from the stirring shaft (8). Fermenter according to one of the preceding claims, characterized in that the fermenter has two, three or four agitators, wherein the stirrer shafts (8) of the agitators are preferably mounted at different distances from the fermenter bottom (2). Fermenter after Claim 11 , characterized in that two stirrers are provided and the axes of the stirrer shafts (8) enclose an angle of 180 ° to each other or that three agitators are provided and the axes of the stirrer shafts (8) enclose an angle of 120 ° to each other or that four agitators provided are and the axes of the stirrer shafts (8) form an angle of 90 ° to each other.

Images