WO2016166213A1

WO2016166213A1 - Method and device for mixing a substrate

Info

Publication number: WO2016166213A1
Application number: PCT/EP2016/058229
Authority: WO
Inventors: Mathias Schlegel; Maik Orth; Norbert Kanswohl
Original assignee: Universität Rostock
Priority date: 2015-04-15
Filing date: 2016-04-14
Publication date: 2016-10-20
Also published as: DE102015105736B3

Abstract

The invention relates to a mixing device (50) for mixing a substrate (30), which mixing device comprises a container (10) for holding the substrate (30) to be mixed. The container is movably arranged in or on the device in such a way that the container (10) is in a first position when there is a specified mass distribution in or on the container (10) and is moved into a second position differing from the first position in accordance with a mass distribution deviating from the specified mass distribution. The mixing device also comprises a mass-shifting apparatus, which is designed to change a mass distribution in or on the container (10), and a control apparatus for controlling the mass-shifting apparatus.

Description

Method and device for mixing a substrate

The present invention relates to a method and apparatus for mixing a substrate.

Devices for mixing a substrate are in the

various technical applications needed. The substrate may be liquid, optionally present with a proportion of solids, or as granules.

In the context of biogas production, it is necessary, for example, a substrate, which consists of a predetermined proportion of

Dry matter and a given proportion of water

composed, to mix. Conventionally, this mixing is done by means of a stirring device. Substantial energy is required to stir the substrate, especially when a high viscosity substrate is present, thereby reducing the efficiency of biogas production.

Object of the present invention is to provide a method and a

To propose a device for energy-efficient mixing of a substrate, in particular for mixing a substrate in the context of

Biogas production.

According to a preferred embodiment, a mixing device for mixing a substrate comprises a container for receiving the substrate to be mixed. The container is in or on the

Mixing device arranged such that the container is in operation at a predetermined mass distribution in or on the container is in a first position or position and is displaced depending on a deviating from the predetermined mass distribution mass distribution in or on the container in a different position from the first position or position. The displacement takes place solely as a result of mass displacement in or on the container.

It is understood that the predetermined mass distribution in the operation of the container is dependent on the type of substrate to be mixed and the amount of substrate in the container. According to a preferred

Embodiment, the mixing device is adapted to adapt the arrangement of the container to a substrate to be mixed and / or to be mixed amount of the substrate. Alternatively or additionally, it may be provided that during operation the predetermined mass distribution, depending on the type of substrate to be mixed and a

predetermined arrangement of the container in or on the mixing device is adjusted based on the filled in the container amount of the substrate.

The mixing device further comprises a

Mass displacement device. This is furnished, one

Mass distribution in or on the container to change - by a mass transfer in or on the container.

The mixing device finally comprises a control device for controlling the mass displacement device. The control device is set up to control the mass displacement device in such a way that the mass displacement device changes the mass distribution in or on the container in such a way that the container is displaced from the first position to the second position due to a changed mass distribution in or on the container. By moving the container from the first to the second position, mixing of the substrate, which is located inside the container, takes place automatically - following the principle of a free-fall mixer. The mixing of the substrate takes place energy-efficient, since only so much energy must be introduced, which is required to a

Mass displacement in or on the container to effect such that the container is displaced from the first to the second position.

A preferred embodiment of a method for mixing a substrate accordingly comprises the following steps:

A container for receiving the substrate is provided.

The container is movably arranged such that the container is in operation at predetermined mass distribution in or on the container in a first position and depending on one of the

predetermined mass distribution deviating mass distribution in or on the container is moved to a different position from the first position second position. The first position and / or the second position may be a quasi-stable positions or equilibrium positions in which the container remains as long as the predetermined mass distribution is present in or on the container.

In a further step, the container is to be mixed with the

Substrate filled. The filling amount is usually determined in such a way that in or on the container, the predetermined mass distribution is achieved. Alternatively, the container may also be first filled with the substrate after provision and then arranged in the manner described above. According to this variant, the achievement of the predetermined mass distribution is ensured in the step of arranging, For example, when a mixing device used to perform the method allows such adjustment in the step of arranging.

The container can be locked during filling. In this way it can be avoided that there is a premature displacement of the container, for example by corrugation in the container.

In order to achieve a mixing of the substrate now in the container, in a further step, a mass distribution in or on the container is changed such that the container is displaced from the first position to the second position.

According to a first preferred embodiment, the body is displaced by the mass displacement from the first position by means of a tilting movement in the second position. It is understood that by means of a corresponding mass displacement in the reverse manner a

Relocation of the body from the second position to the first position is possible. The first and the second position are preferably provided as quasi-stable positions, in which the body stabilizes in each case when the mass distribution in or on the body remains unchanged. This may be achieved, for example, by a suitable arrangement, e.g. a suitable suspension, the body can be achieved relative to its center of gravity.

According to a second preferred embodiment, the body is set in a rotational movement by suitably controlled mass displacement from the first position to the second position. Here, it is advantageous if the body is rotationally symmetrical and suspended accordingly, in order to avoid a large amount of energy in a preferably to be continuously rotated.

The mass transfer device can be formed in various ways. According to a first preferred embodiment, the mass transfer device is as a

Level change device formed. The

Level change device is set up to change the level, that is to say the filling level, of the substrate in the container. Due to a changed level of the substrate in the container, a mass displacement occurs in the container, which then leads to the displacement of the container from the first to the second position.

According to a first variant, the level-changing device may be arranged to change the level of the substrate in the container by adding substrate or at least substrate components, such as water, to the container or draining it from the container. Due to the fact that, with suitably adjusted mass distribution in the container, only a very small amount of substrate has to be supplied or removed in order to bring about the desired effect of displacement of the container from the first to the second position, feeding or discharging adversely affects one small amount of substrate to or from the container, the mixing process practically not. Furthermore, such a loading or unloading of substrate with

take place comparatively low energy consumption. to

Level reduction drained substrate can be recycled to increase the level, so that the initially filled in the container amount of substrate is retained.

According to a second variant, the level change device can be designed as a displacement device. The Displacement device is set up to displace substrate within the container. Also, this can change the level of the substrate in the container; the level of the substrate will increase.

The displacement device may comprise at least one expansion device which is set up to expand when being filled with a fluid. The expansion of the expander located inside the container results in displacement of substrate in the container, thereby increasing the level of the substrate in the container and eventually mass shifting in the container. As the expansion means, in particular, a balloon or the like which can be expanded by gas or the like can be used.

According to a second preferred embodiment, the

Mass displacement device to be configured to cause a mass displacement of the container itself. In this case, the mass displacement can be carried out in particular independently of the substrate in the container as well as independently of a level of the Substarts in the container.

According to a first variant, a mass displacement on the

Container, for example, by filling, for example by means of a fluid, and emptying one or more separate chambers of the container. These chambers are different from the chamber of the container, which comprises the substrate. The effect on the

Mass distribution of the container is analogous to a previously described feeding and discharging substrate components to or from the container. According to a second variant can on the container movable weights or the like to be movably mounted, for example on rails movable weights. The

Mass displacement device is arranged according to this variant, a displacement of these weights, and thus to effect a mass displacement of the container.

Preferably, the container is arranged such that it can be moved rotatably or tiltably about at least one predetermined axis. A corresponding container may for example comprise at least one pin which is arranged on the container, as a rule hanging on a frame or the like. The pin is arranged on the container such that the container at a predetermined mass distribution associated filling quantity of the substrate is so skewed that already a small mass displacement on or in the

Container leads to a tilting or turning of the container. The tilting or turning is usually done about a predetermined axis, which is defined for example by the pin described above.

According to a further preferred embodiment, the

Mixing device a generator for power generation. The

Mixing device is set up by means of a

Displacement movement of the container from the first to the second position to drive the generator, for example via a suitable transmission. It is also possible that the semicircular movement is implemented in tilting the container by a flywheel in full circle rotations to drive a generator. In this way, a considerable amount of torque, which can be generated by the displacement movement of the container, in addition to the mixing of the substrate, can be used to generate electricity by means of the generator. The container of the mixing device may comprise, inside the container, mixing means supporting the substrate, fixedly mounted on the container or freely movable in the container. As a fixedly mounted on the container mixing devices, for example

Shovels, baffles or the like may be provided. Examples of free mixing devices in the container are buoyant bodies which can be added to the substrate during operation.

As already mentioned, the mixing device is arranged according to a particularly preferred embodiment, organic substrate in

Framework of a biogas production. The container of the mixing device is preferably designed as a hydrolysis or fermenter.

A preferred embodiment of a biogas plant according to the invention comprises a mixing device of the type described above.

Particularly preferably, the biogas plant comprises a mixing device, in which the mass displacement device is designed as a displacement device with at least one expansion device. The

Biogas plant is set up to fill the expansion device with obtained in the context of biogas production, and possibly additionally compressed fluid. In this way, the energy from the fluid produced in the biogas production can be exploited particularly efficiently.

It is understood that the mixing device according to the invention

is basically suitable for mixing any substrates and is not limited to the mixing of substrates in the context of biogas production. Another preferred application is, for example, the Treatment of plants in feed production.

In the following, the invention will be described with reference to the attached

Drawings described by way of example. As show in it:

FIGS. 1A and 1B show a preferred embodiment of a container of a mixing device according to the invention;

Figure 2 schematically shows a displacement of the container of Figure 1 from a first to a second position; and

FIG. 3 shows components of a biogas plant with a preferred embodiment of a mixing device according to the invention.

The following description of the invention is made by way of example with reference to a mixing device in the context of biogas production. Other applications are also possible.

In FIGS. 1A and 1B, a container 10 of a mixing device 50 is shown in FIG

Top view and shown in side view. The container 10 is adapted to receive substrate to be mixed in the context of biogas production. The container 10 may be formed, for example, as a hydrolysis tank or as a fermenter.

The container 10 is formed circular cylindrical in the example shown. In principle, however, the shape of the container 10 is practically not limited as long as the container 10 is adapted to receive the substrate to be mixed and to be displaced in the manner described below. To an arrangement, ie with reference to the example shown a

Suspension, to allow the container 10 such that the container 10 is at a given mass distribution in or on the container 10 in a first, quasi-stable position shown in Figure 1 B (see also Fig. 2, state 1 ), and, depending on a mass distribution deviating from the given mass distribution, in or on the container 10, due to a mass displacement in or on the container 10, is displaced into a second position different from the first position (see Figure 2, state 2), 10 pins 12 are arranged on the container, on which the container 10 is suspended, for example on a (not shown) frame.

The pins 12 are, with respect to the circular cross section of the container 10, not arranged diametrically, whereby a first position shown in Figure 1 B can be achieved. A mass displacement in the container 10, which is explained below with reference to Figure 2, then allows a displacement of the container 10 from the first position shown in Figure 1 B in a second position shown in Figure 2 ("Condition 2"), the Displacement in the present example as a

Tilting movement takes place about an axis which is predetermined by the longitudinal direction of the two pins 12 (see Fig. 2, state 1 .2).

In principle, the container 10 can also be arranged or suspended in other ways, for example on only one pin 12 or in another manner. It is preferred if the arrangement of the container 10 in the first position can be achieved such that even a small mass displacement in or on the container 10, measured on the mass of the container 10 in operation, to a shift from the first to the second Position leads. On the one hand, such an arrangement, with known container geometry, known substrate and known filling amount of the substrate to be calculated in a conventional manner. On the other hand, it is possible for a given container 10 to adjust the arrangement by the level of the substrate.

The container comprises, as indicated in Figure 2, a

Mass transfer device in the form of a

Level changing means. The level change device is designed as a displacement device and comprises two

Expansion means in the form of two balloons 22. Number, shape and arrangement of the balloons 22 in the container can vary. The balloons 22 are adapted to be filled by a fluid, thereby expanding, as indicated in Figure 2 with respect to the state 1 .1. Draining the fluid allows the

Expansion of the balloon 22 back (see Fig. 2, state 1 .2).

After the container has been arranged and filled as described above with reference to FIG. 1, mixing of the substrate 30 located in the container 10 is achieved, as indicated in FIG. 2 with reference to state 1 .1, by the balloons 22 be filled with gas. A resulting expansion of the balloons 22 results in a displacement of the substrate 30 in the container 10 and, consequently, an increase in the level of the substrate 30 in the container 10. This increase in level leads to a mass displacement in the container 10

Mass displacement tilts the container 10, as shown in Figure 2 with respect to the state 1 .2, from the first, stable position in the arrow direction in the second, stable position, which is referred to in Figure 2 as state 2.

After the tilting of the container 10 from the first to the second position has been initiated, the gas can be discharged from the balloons 22 again. Discharge is by the pressure that the substrate 30 on the Balloons 22 exercises, supports.

The filling of the balloons 22 with gas or the discharge of gas from the balloons 22 is thereby controlled by a control device (not shown) of the mixing device 50. The control device can, for example, fall back on a current position of the container detected by means of a suitable sensor (not shown). In this way, the controller can detect when a filling with gas or a

Draining the filled gas is required to complete the

Displacement movement of the container 10 to effect.

It is understood that starting from the second position, in an analogous manner, i. E. by refilling the balloons 22 with the result of an increase in the level of the substrate 30 in the container 10, tilting of the container 10 from the second position to the first position can be achieved. In this way, the container 10 can be alternately displaced from the first to the second position and back. A thorough mixing of the substrate 30 located in the container 10 takes place automatically.

It can be provided that the container in the positions shown in Figure 2, with states 1 and 2 state, i. in the first and second position, is secured to a further tilting operation, for example by automatically controlled pin locks. Such a fuse is, for example, for a substrate filling and

Substrate emptying advantageous.

Furthermore, it is possible that a tilting operation of the container described above is braked in a suitable manner to intercept the high loads arising during tilting. The mixing device 50 may further include a generator (not shown). This generator can, for example via a suitable transmission, with the container 10 or the pin 12 of the container 10 may be coupled. A tilting movement of the container 10 from the first to the second position (and / or vice versa) may then drive the generator via the transmission. As a result, current can be generated in a basically known manner by means of the generator.

Finally, FIG. 3 shows various components of a biogas plant 100, which comprises a mixing device 50 from FIG. A discharge of fluid generated in the container 10, for example hydrolysis gas, usually takes place when the container 10 is in the first position. The gas is supplied through a gas-tight pressure hose 105 a gas pressure accumulator 1 10. As a rule, a valve in the pressure hose 105 only opens to discharge the gas from the container 10 when a sufficient overpressure is present in the container. The fluid arises from the biodegradation processes themselves, which take place in the container. As long as the pressure in the gas pressure accumulator 1 10 is not high enough to fill the balloons 22, gas can be passed from the pressure accumulator 1 10 via a compressing compressor 1 15 in another gas pressure accumulator 120.

For the filling of the balloons 22 preferably gas is used, which in the gas pressure accumulator 1 10 - or the further gas pressure accumulator 120 - is present. The pressure held there should in each case be higher than the hydrostatic pressure prevailing in the interior of the container 10 at the point at which the balloons 22 are arranged, so that a rapid filling of the balloons 22 can take place. Alternatively, the balloons 22 may also be filled by means of a gas which is a separate one

Gas accumulator is removed. The introduction of the gas into the balloons 22 and the discharge of the gas from the balloons 22 is subject, as already mentioned, one

Control device of the mixing device 50. From the balloons 22nd

vented gas can now be depressurized for subsequent use, e.g. combustion in a combined heat and power plant, storage, etc., are supplied.

The mixing of the substrate 30 in the container 10 may be additionally assisted by suitable mixing means (not shown) in the container 10, such as blades or baffles fixedly or movably disposed in the container 10, and / or freely movable in the container added, preferably abrasion

Buoyancy, which preferably have an irregular shape and thereby introduce an additional movement in the substrate to be mixed.

Claims

Patent claims

1 . Mixing device (50) for mixing a substrate (30),

full

a container (10) for receiving the substrate (30) to be mixed, wherein the container (10) is movably arranged such

that the container (10) is in a first position for a given mass distribution in or on the container (10) and

is displaced in or on the container (10) to a second position different from the first position, depending on a mass distribution deviating from the predetermined mass distribution,

a mass transfer device which is set up, a

Mass distribution in or on the container (10) to change, and

a control device for activating the mass transfer device, which is set up to control the mass transfer device such that the mass transfer device changes the mass distribution in or on the container such that the container is displaced from the first position to the second position.

2. mixing device (50) according to claim 1, wherein the

Mass displacement device is designed as a level-changing device which is adapted to change the level of the substrate (30) in the container (10).

3. mixing device (50) according to claim 2, wherein the

Level change means is arranged to change the level of the substrate (30) in the container (10) characterized in that substrate (30) or at least

Substrate components are added to the container (10) or drained from the container (10).

4. mixing device (50) according to claim 2, wherein the

Level change device is designed as a displacement device, which is adapted to displace substrate (30) within the container (10).

5. mixing device (50) according to claim 4, wherein the displacement means comprises at least one expansion means (22) which is adapted to expand when filled with a fluid.

6. mixing device (50) according to claim 1, wherein the

Mass displacement device is arranged to effect a mass displacement of the container (10).

7. mixing device (50) according to any one of claims 1 to 6, wherein the

Mixing device (50) is adapted to adapt the arrangement of the container (10) to a substrate to be mixed (30) and / or to a mixing amount of the substrate (30).

8. mixing device (50) according to one of claims 1 to 7, wherein the container (10) is arranged such that it is rotatable or tiltable about at least one predetermined axis.

9. mixing device (50) according to any one of claims 1 to 8, wherein the

Mixing device (50) comprises a generator for generating electricity and is arranged to drive the generator by means of a displacement movement of the container (10) from the first to the second position.

The mixing apparatus (50) according to any one of claims 1 to 9, wherein the container (10) internally facilitates mixing of the substrate (30), fixed or movable on the container (10), or freely movable in the container (10)

Includes mixing devices.

1 1. Mixing device (50) according to one of claims 1 to 10, wherein the

Mixing device (50) is arranged to mix organic substrate in the context of biogas production.

12. mixing device (50) according to claim 1 1, wherein the container (10) as

Hydrolysebehälter or fermenter is formed.

13. biogas plant (100), comprising a mixing device (50) according to any one of claims 1 1 or 12th

14. biogas plant (100) according to claim 13 with a mixing device (50) according to claim 5, wherein the biogas plant (100) is adapted to fill the expansion device with gas obtained in the biogas production.

15. A method of mixing a substrate (30), comprising the steps of:

Providing a container (10) for receiving the substrate (30), movably arranging the container (10) in such a way,

Filling the container (10) with the substrate to be mixed;

Changing the mass distribution in or on the container (10) such that the container (10) is displaced from the first position to the second position.