Biogas plant

Abstract

A biogas plant contains a fermenter vessel, in which an assembly support is mounted, preferably vertically oriented. An assembly, in particular a submersible motor driven stirrer, is retained by a height adjustment device so as to be vertically adjustable on the assembly support. Accordingly, the height adjustment device is formed by a belt drive of which a traction device is guided around at least two deflecting elements spaced apart from one another in the longitudinal direction of the assembly support. At least one of the deflecting elements can be driven in rotation by a driving device and the assembly is coupled to the traction device in such a way that when the deflecting element is rotationally actuated in a first direction the assembly is raised and when the deflecting element is rotationally actuated in a second, opposite direction, the assembly is lowered.

Claims

1. A biogas plant, comprising: a fermenter tank having a tank inner space; an upper chain wheel; a lower chain wheel spaced apart from said upper chain wheel; an articulated traction chain mounted vertically within said tank inner space and engaging with said upper and lower chain wheels, said articulated traction chain having axes of articulation which are oriented axially parallel to an axis of rotation of said upper and lower chain wheels; a carrier coupled to said articulated traction chain; a submersible motor-driven agitator mounted on said carrier; an outlet orifice for drawn-up solids positioned above said upper chain wheel, said outlet orifice having two lead jaws spaced apart and set obliquely, said two lead jaws ensuring a functionally reliable engagement between said articulated traction chain and said upper chain wheel; and an arcuate lead plate positioned below said lower chained wheel.

2. The biogas plant according to claim 1, wherein said upper chain wheel and said lower chain wheel are secured to said carrier indirectly or directly.

3. The biogas plant according to claim 1, wherein said articulated traction chain is selected from the group consisting of a multi-dimensionally movable chain and a merely one-dimensionally movable articulated chain.

4. The biogas plant according to claim 1, wherein said articulated traction chain is selected from the group consisting of a roller chain, a bush chain and a bolt chain.

5. The biogas plant according to claim 1, wherein said carrier is mounted oriented vertically in said fermenter tank.

6. The biogas plant according to claim 1, wherein: said submersible motor-driven agitator has a tie-up point; and said articulated traction device is guided from said tie-up point on said submersible motor-driven agitator upward in a direction of a vertical axis around said upper chain wheel and from there downward to said lower chain wheel, from where said articulated traction chain is guided upward again back to said submersible motor-driven agitator and is tied up there.

7. The biogas plant according to claim 6, wherein said lower chain wheel is disposed indirectly or directly on said carrier and is mounted rotatably.

8. The biogas plant according to claim 1, wherein said upper chain wheel is assigned a motor, by means of said motor said upper chain wheel can be driven in rotation indirectly or directly.

9. The biogas plant according to claim 8, wherein said motor is electrically, hydraulically, or pneumatically operatable.

10. The biogas plant according to claim 8, further comprising: a gear; and a drive shaft, said upper chain wheel is an integral part of said drive shaft, said drive shaft further having a drive pinion which cooperates with said gear which drives said drive pinion and consequently said upper chain wheel.

11. The biogas plant according to claim 10, further comprising: a hollow shaft configuration, said gear being an integral part of said hollow shaft configuration, said hollow shaft configuration further having a hollow shaft forming a ceiling wall rotary bearing and/or forming an integral part of said carrier, a further drive shaft mounted rotatably, which has an engagement region meshing indirectly or directly with said drive pinion and which is led with a free end out of said fermenter tank, there being provided said motor which drives said further drive shaft.

12. The biogas plant according to claim 11, wherein said gear is a worm drive with a worm shaft as said further drive shaft, and said engagement region of which is formed by a worm thread.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) In the drawing:

(2) FIG. 1 shows a diagrammatic part view of a fermenter tank of a biogas plant with an assembly carrier mounted vertically therein and with an exemplary embodiment of a height adjustment device according to the invention,

(3) FIG. 2 shows diagrammatically, in the form of a detail, an enlarged illustration of the wrap-around drive of FIG. 1,

(4) FIG. 3 shows diagrammatically a sectional view along Y-Y of FIG. 2,

(5) FIG. 4a shows diagrammatically an exemplary illustration of a chain region of an articulated chain designed, for example, as a roller chain,

(6) FIG. 4b shows an arrangement, tilted through 90, of the chain region of FIG. 4a,

(7) FIG. 5a shows diagrammatically a further exemplary embodiment, alternative to FIG. 1, with a hollow shaft arrangement,

(8) FIG. 5b shows, in the form of a detail, a diagrammatic sectional view through the upper rotary bearing, designed as a hollow shaft arrangement, of the assembly carrier according to FIG. 5a.

DESCRIPTION OF THE INVENTION

(9) FIG. 1 shows by way of example and diagrammatically a part view of a fermenter tank 1 of a biogas plant, in which an assembly carrier 2 is mounted, oriented vertically.

(10) The assembly carrier 2 may, in principle, be designed in various ways, for example to be round. In the embodiment shown here, the assembly carrier 2 is formed by a square lead pipe of square cross section.

(11) The assembly carrier 2 is rotatable, that is to say it is mounted rotatably about its longitudinal axis in the fermenter tank 1. For this purpose, the assembly carrier 2 has a lower rotary bearing 3 and an upper rotary bearing 4. The lower rotary bearing 3 is formed by the fermenter tank bottom wall, while the upper rotary bearing 4 is formed here, for example, by a ceiling wall of an L-type servicing shaft 5. This L-type servicing shaft 5 covers a ceiling wall-side servicing orifice 6, not illustrated in detail here, of the fermenter tank 1, so that no gases can escape out of the tank inner space 9 into the surroundings. The L-type servicing shaft 5 has, for example, two wall plates 7, 8 which in a servicing situation can be removed from the L-type servicing shaft 5, so that access into the fermenter tank inner space 9 is made possible via the servicing orifice 6.

(12) In a servicing situation, the assembly 10, which is mounted in a height-adjustable manner on the assembly carrier 2 and is formed here, for example, by a submersible motor-driven agitator, can then, by the assembly carrier 2 being pivoted about its longitudinal axis, be pivoted to the left through 180 out of the right-hand position shown in the image plane of FIG. 1, and subsequently, by actuation of the height adjustment device 11, explained in more detail below, can be raised upwardly to an extent such that the assembly 10 is accessible via the servicing orifice 6 or can be displaced outside the fermenter tank 1 through the servicing orifice 6.

(13) Instead of an L-type servicing shaft 5, as shown in FIG. 1, a box-shaped servicing shaft 12 may also be provided, as is depicted merely by dashes in FIG. 1, into which the assembly 10 can be moved for servicing and repair work and which is accessible, for example, via an access door or access flap.

(14) The height adjustment device 11 is formed here by a wrap-around drive, in which an articulated chain 13, movable here, for example, only one-dimensionally, as a traction means or traction chain is guided from a first tie-up point 14 on the assembly 10 upward in the direction z of the vertical axis around a chain wheel 15 and from there downward to a here, for example, lower chain wheel 38 as a lower deflection element which is mounted rotatably on the assembly carrier 2. As may be gathered particularly from FIG. 2, in this embodiment the two chain wheels 15, 38 may be fastened indirectly or, as shown here, directly to the assembly carrier 2 via mounting trestles or mounting plates 39, for example by means of a plurality of screw connections 40. For this purpose, the mounting trestles or mounting plates 39 may preferably be designed to be angled such that the planes of rotation of the chain wheels 15, 38 lie approximately in the longitudinal mid-plane of the assembly carrier 2, so that the assembly 10 itself, oriented approximately centrally, is height-adjustable along the assembly carrier 2. It will be appreciated that the arrangement of the assembly 10 offset with respect to the longitudinal mid-plane of the assembly carrier 2 is, of course, also possible in principle.

(15) The articulated chain 13 is then guided from the lower chain wheel 38 upward again back to the assembly 10 and is tied there with its second free end region to a second tie-up point 41 which here, merely by way of example, lies so as to be spaced apart from and below the first tie-up point 14 of the first free articulated chain end region.

(16) Thus, by means of a set-up of this type, a wrap-around drive is formed, into which the assembly 10 is incorporated in such a way that the assembly 10 can be raised upon rotary actuation of the chain wheel 15 via an electric, pneumatic or hydraulic drive motor 19, flanged, for example, to the upper mounting plane 19 and/or to the assembly carrier 2, in a first direction and can be lowered upon rotary actuation of the chain wheel 15 in a second, opposite direction.

(17) The drive motor 19 is here coupled or operatively connected via piping, hosing or cabling 21 to an actuation device 20 arranged outside the fermenter tank 1.

(18) As is evident particularly from FIG. 2, the free chain region 42 of the articulated chain 13, that is to say that chain subregion, into which the assembly 10 is not incorporated, between the two chain wheels 15 and 38, is guided here, free of obstruction, for example, through a leadthrough 43 formed on the assembly side. This assembly-side leadthrough 43 may be designed, for example, as a slot, gap or such like recess, moreover with or without a guide element, such as, for example, a guide roller or the like. Alternatively to this, however, the chain wheels 15, 38 could also be offset with respect to the longitudinal center of the assembly carrier 2 such that, for example in the case of chain wheel diameters designed to be correspondingly large, the free movement of the free chain region 42 is ensured via the arrangement and/or dimensioning of the chain wheels 15, 38. Alternatively, also, if appropriate, the arrangement of the chain wheels 15 and 38 could also be such that the free chain region 42 runs inside the assembly carrier 2 which is preferably designed as a hollow profile carrier. Furthermore, further deflection elements or tension elements could also be provided, which, for example, supplement and extend the wrap-around drive, shown here, in such a way that chain guidance is designed in the manner of a block and tackle and it is ensured that the free chain region 42 always lies outside the range of movement of the assembly 10.

(19) Moreover, by means of a tension element, the chain tension can be maintained in the desired way, in order to prevent the chain from jumping out. Alternatively or additionally to this, in connection with both chain wheels 15, 38, as illustrated diagrammatically in FIG. 2, there may also be provision, in turn, for providing there lead elements 25 which have a gap clearance with respect to the chain wheel such that the articulated chain 13 is held permanently in engagement connection with the in each case assigned chain wheel 15 or 38.

(20) If, then, as illustrated diagrammatically in FIG. 1, the assembly 10 is to be lowered out of the raised position, shown by unbroken lines, downward into the fermenter tank 1, the drive motor 19 is activated by the actuation device 20 for a predetermined time duration such that said drive motor rotates the chain wheel 15 clockwise until the assembly 10 is lowered into the desired lowered position 26, illustrated here, for example, by dashed lines. When the desired position is reached, the drive motor 19 is stopped and consequently the chain wheel 15 is halted, with the result that the assembly 10 is held reliably in the desired lowered position 26.

(21) It will be appreciated that both the length of the articulated chain 13 and the distance between the two chain wheels 15, 38 are, of course, stipulated such that all the desired height positions of the assembly 10 in the fermenter tank 1 can consequently be assumed.

(22) If the assembly 10 is then to be raised again from the lowered position 26, illustrated by dashes in FIG. 1, into the higher position, illustrated by unbroken lines, once more the drive motor 19 is activated via the actuation device 20, specifically, this time, such that the chain wheel 15 is rotated counterclockwise, as a result of which, in turn, that region of the articulated chain 13 which is tied to the assembly 10 at the first tie-up point 14 and therefore the assembly 10 are drawn upward.

(23) It will be appreciated, further, that the solution according to the invention can, of course, be used with any type of tank or fermenter tank, that is to say, in particular, also with fermenter tanks having a fixed horizontal ceiling wall and with fermenter tanks having a sheet roof or the like.

(24) Provided in each case above the upper rotationally drivable chain wheel 15 and below the lower chain wheel 38 in the direction z of the vertical axis is a lead element 25a, 25b which has a defined gap clearance in relation to the respective chain wheel 15, 38, in such a way that the articulated chain 13 is held permanently in engagement connection with the chain wheel 15. The lower lead element 25b is designed here, for example, to be arcuately curved and is guided, for example, in the form of a lead plate or the like around a large part of the engagement region of the lower chain wheel 38. By contrast, the upper lead element 25a is formed here, for example, in two parts by lead jaws 25d, 25e which are spaced apart from one another and between them form an outlet orifice 25c and which here are set obliquely, for example, in a roof-shaped manner, thus ensuring that solids drawn up by the articulated chain 13 can be discharged in a functionally reliable manner via the outlet orifice 25c and consequently the risk of blockage in the region of the upper chain wheel 15 is avoided. Such lead elements 25a, 25b thus ensure a functionally reliable engagement connection between the articulated chain 13 and the respective chain wheel 15, 38 and therefore, in particular, help to prevent the articulated chain 13 from jumping out of the engagement connection with the chain wheel 15 or 38.

(25) As may be gathered particularly from FIG. 4a and FIG. 4b, the traction chain is formed here, for example, by a one-dimensionally movable articulated chain 13, the axes of articulation 32 of which are oriented essentially axially parallel to the axis of rotation of the chain wheel 15, with the result that reliable guidance of the assembly 10 both during raising and during lowering is achieved. In particular, an articulated chain 13 of this type ensures that floating or foam layers 27 possibly present, which are illustrated in FIG. 1 only extremely diagrammatically and by way of example, can be punctured reliably when the assembly 10 is being lowered, since, contrary to an overall flexurally slack rope, the articulated chain 13 does not permit any major shifting movements of the assembly and therefore the puncturing of the floating layer 27 can take place in a more controlled way.

(26) Moreover, such an articulated chain 13 as traction chain makes it possible to stabilize the assembly 10 when the latter is in operation, this having an advantageous effect, for example, upon the agitation result.

(27) As shown in FIGS. 4a and 4b, the articulated chain is formed here, for example, by outer link plates 28 which are connected to one another via bolts 30 and are spaced apart from one another. Inner link plates 29 are mounted pivotably on the bolts 30, in each case rollers 31 being mounted rotatably on the bolts 30 between the two inner link plates. By means of such an exemplary set-up of an articulated chain 13, advantageous flexural rigidity in the direction of the axes of articulation 32 and to some extent also in the chain longitudinal direction is thus achieved. Articulation is provided to the desired extent around the axes of articulation 32 only.

(28) By means of such an articulated chain 13 as traction chain of a height adjustment device, therefore, desired transverse stabilization and guidance stabilization of an assembly during its height adjustment are made possible, this having a positive effect both on the lowering operation and on the raising operation and, moreover, also resulting in positive effects upon the agitation result by means of the assembly 10 designed, for example, as a submersible motor-driven agitator.

(29) Although the above exemplary embodiments were described in terms of the use of an articulated chain, a multidimensionally, in particular two-dimensionally movable traction chain, for example a link chain, such as, for example, a round link chain, may, of course, be employed and used instead of an articulated chain of this type.

(30) Moreover, FIG. 5a shows a refinement, alternative to FIG. 1, in which the chain wheel 15 arranged at the top is an integral part of a drive shaft 17, on which, furthermore, is mounted (FIG. 5b) a drive pinion 17a which cooperates with a worm drive 17b which drives the drive pinion 17a and consequently the chain wheel 15. The worm drive 17b is an integral part of a hollow shaft arrangement, in which, in a hollow shaft 3a forming the ceiling wall rotary bearing 3 and forming an integral part of the assembly carrier 2, a worm shaft 17c is mounted rotatably, which has a worm thread 17d meshing here directly with the drive pinion 17a (the interposition of one or more gear wheels would, of course, also be possible) and which is guided with a free end 17e out of the fermenter tank 1, illustrated in FIG. 5b, for example, by a ceiling wall 5a, depicted by dashes, of the servicing shaft 5. Provided there is a drive motor 19 (FIG. 5a) which drives the worm shaft 17c and which is illustrated here only extremely diagrammatically and by way of example. This drive motor 19 can be actuated by an actuation device 20 which is likewise arranged outside the fermenter tank 1, for which purpose the drive motor 19 is connected by means of a signal line 20a, illustrated by dashes here. It will be appreciated that the drive motor 19, together with the worm shaft 17c, is designed such that the worm shaft 17c and consequently the drive pinion 17a and the chain wheel 15 can be driven in rotation both in one direction and in the other direction.

(31) Furthermore, outside the fermenter tank 1 a further drive motor 21 is arranged (FIG. 5a), by means of which the hollow shaft 3a connected firmly to the assembly carrier 2 and, consequently, the assembly carrier 2 can be pivoted via a gear arrangement 21a, not illustrated any further here. The activation of the drive motor 21 likewise takes place via the actuation device 20 by means of a signal line 20b. It should be expressly mentioned at this juncture that the pivoting of the assembly carrier 2 may alternatively also take place manually, for example via a pivoting lever, although this is not illustrated here. The worm shaft 17c could likewise also be driven manually, for example by means of a crank handle, although this is not illustrated here.