DE3627665C2 - - Google Patents

Description

The registration is based on a method and a device for fine-bubble fumigation 9. A liquid according to the preamble of claims 1 and 9, respectively.

From US-PS 32 34 123 is a device for ventilation of wastewater known by several perforated, elastic and uses tubular membranes, which are laid within a basin and by means of spiral springs are attached to the pool edge. About a common one The supply line becomes the tubular membranes supplied with compressed air, whereby by increasing the gas pressure the clamped hoses more inflated and in small extent can also be stretched in the longitudinal direction. To The hoses laid in the pool are fixed in position weighted with lead wires on the bottom of the Hose are incorporated into the hose. With an increase the gas pressure is loaded by the tightly clamped one Tubing on stronger, causing the membrane to stretch changed in the longitudinal direction and the tensile force of a coil spring is also changed.

DE-AS 17 84 298 is a device for fine bubbles Aeration of waste water by means of an elastic membrane known that at one end to an air supply line connected and closed at its other end Has air hoses, the underside of which is not perforated and the top of which has a large number of air outlet openings having. Open the air outlet openings at a certain pressure in the air hose and close when there is no pressure. The air hoses are formed flat and elastic and on their  Longitudinal edges each held by a support member. Neighbors Support members have such a mutual distance from each other on that in the loops over them drawn air hose in its flat position, in which it is not is filled with air, receives a certain bias, whereby its top and bottom almost close to each other leagues. This is said to still exist in the air hose Air or newly entering wastewater through the air outlet openings be pushed out.

In the known device, the support members hold the Air hoses only tight, but do not stretch at all the air hoses. An expansion of the air hoses or Membrane cannot be cut lengthways and crossways Change of position of the rigid with the air supply line connected support members can be effected.

From DE-OS 32 18 460 is a device for fine glass Aeration of water by means of hose-like, perforated Slides known on a flexible support tube are attached, the support tube or a rubber jacket executed in the area of the bends without perforations are. A change in the state of stretch of the elastic Membranes are only possible through an increased gas supply possible.

DE-PS 29 42 607 describes a device for large-area, known as fine-bubble fumigation of liquids, with a perforated air distribution film with its edges clamped in a closed frame and over one also unperforated film clamped in the frame  is arranged so that the perforated air distribution film at lack or little air supply on the non-perforated film fits snugly. Both below the non-perforated film as well as above the perforated air distribution film staggered webs between the sides of the frame, which give the films stability. In addition the perforated air distribution film can be attached to the non-perforated Foil facing inside with a glass fiber reinforced Provide plastic layer as a support body be a special one of the perforated air distribution film Stiffness gives, so that a greater bulge the perforated air distribution film by the air pressure too between those arranged above the unperforated film Webs is avoided.

In a conventional use of the known device for fine bubble aeration of water in aeration tanks from biological sewage treatment plants or for the supply of oxygen in However, fish farming ponds or the like encounter problems with regard to an even gas distribution and one Clogging of the perforation holes from the liquid side come on. An even gas distribution depends on both of the size of the individual passage openings as also the differential pressure between the inside and the outside the air distribution film. Due to the dust content of the used Compressed gases, but especially due to constipation of the openings from the liquid side forth in continuous operation, occur with this and others known devices inevitable impairments on which over time an uneven bubble pattern and / or result in an increased pressure loss.  

Eliminating the inevitable constipation during the operation only works with the known devices incomplete, so that there is always an increase in pressure loss an uneven bubble pattern, or at least one partial interruption of the operational process for ent distance and cleaning of the device can be accepted got to.

With a fine bubble distribution of the gas in the concerned Liquid is also as uniform as possible Gas distribution in relation to the footprint of the Liquid container or parts thereof desired. Will for this purpose aerator pipes, plates or hoses in the A few decimeters apart, so often arises in the company above the fumigation points undesirably rapid upward flow of the liquid-gas bubble mixture, which is a reduction in the length of stay of the gas in the liquid and thus, for. B. when oxygen is introduced from air into water, a results in a sharp reduction in efficiency. Each the specific admission of gas to the aerator is, the lower the efficiency in the resolution of the gas in the liquid in question.

DE-OS 33 18 412 is a device for introduction a gas into a liquid, especially into a Waste water to be treated is known, in which rubber-elastic, tubular membranes are used, the walls of which Have perforations through which the fed Gas passes from the inside out and bubbles in the surrounding liquid gets. The one in the walls  perforations provided for the membranes exist from transverse slots arranged to the longitudinal axis of the membranes. The tubular membranes are on Support bodies attached.

DE-OS 27 57 255 describes a method for fine distribution of liquids in gases and / or of gases known in liquids, in which the finely distributed Fabric under pressure due to a closed on one side, perforated guide tube is guided and from there flexible perforated disks is dispensed on the circumference of the perforated support tube are provided.  

A disadvantage of these known devices is that the fine perforations from outside with substances from the surrounding liquid get clogged. Because of the related Increase in pressure loss, i.e. the reduction the differential pressure required for the passage of the Gas through the perforations is required need from time to time with the help of larger ones Gas flow rates, i.e. under increasing internal pressure or using instead of gas Liquids washed away the perforations will. With particularly finely perforated Ventilation devices is for the purpose of Flushing additionally an expansion of the entire Foils  or ventilation hoses required.

Another disadvantage of the known ventilation directions is the relatively large pressure drop that then for a uniform gas distribution must be applied when it comes to large aggregates or if several aggregates in parallel from be fed from a compressed gas source.

Another disadvantage of the known devices is that due to the constructive Ausge Design of devices for gassing liquid only limited areas of a container can be occupied, because on the one hand the Brackets require considerable space say and thus a close contact of the prevent individual ventilation devices and on the other hand due to the considerable pressure losses Always limited lengths of the ventilation device can be provided or in certain Distances to each other compressed air supply hoses must be seen the compressed air in the Vorrich Feed in ventilation systems for liquids.

The object of the present invention is a Ver drive and a device for fine-bubble loading gases from liquids of the type mentioned to indicate that a low Druckver lust and an even, fine-bubble fumigation ensure the liquids are removed possible blockages in operation without mentioning worthy business interruption and without application allow a significantly increased internal pressure and covering areas of any size of a container ensure terbodens.

This object is achieved according to the invention solved by the features of claims 1 and 9, respectively.

The solution according to the invention provides one in operation low pressure drop and an even, fine Bubble fumigation of the liquid safely and enables clears up any blockages during operation without significant operation interruptions and without applying an elevated Gas pressure and thus insufficient fumigation the liquid in question and ensures a close together of the individual devices lines, so that arbitrarily large areas of a container can be occupied.

The elastic membrane can be used during operation stood either stretched or relaxed, so that them to clean the perforations from storage stanchions, blockages or the like. opposite ge is tensioned or relieved. The discharge and deh The elastic membrane can either be on site unchangeable clamping of the elastic mem bran through increased gas supply or at constant Gas supply by exerting a pull on the elastic membrane at the clamping points be put. A combination of both measures to produce the stretched state is also possible Lich.

An advantageous embodiment of the fiction moderate solution is characterized in that the tubular elastic membrane in the longitudinal direction by a predetermined, fixed amount, preferably by 15 to 25%, compared to their dimensions at rest state is stretched.

Already with a 10% stretch of the elastic The pressure drop of the gas on the material Half or less lowered, due to the deh the individual perforations naturally expand far that by this measure alone Supply of compressed gas makes it easier for the Gas can be made in the liquid.

In the event of an inevitable increase in pressure lustes during continuous operation due to a unavoidable increase in individual perforation tion can be by total or partial cancellation the state of stretch of the elastic membrane and a subsequent restoration of the original Lichen expansion state the pressure loss on the Initial value of a new aerator reduced will.

It has proven to be particularly advantageous for a variety of tubular elastic mem branen part of a common gas supply the elastic diaphragm Block gas supply, leaving the remaining tubular elastic membranes reinforced Gas is supplied. Then the will continue gas-fed tubular elastic mem branen gas supply is blocked, so the previous relaxed tubular elastic membranes stretched by increased gas supply, so that a Rei some of the elastic membranes from constipation or deposits in the normal operating process possible is.

According to a further embodiment of the fiction moderate solution can be used if the ver The perforations also block the pressure gas supply are briefly interrupted, then the stretched state is released and the gas from the be drained inside the elastic membrane, so that the elastic membranes through the outside pressure of the liquid to be compressed. On then pressurized gas is supplied again and the elastic membrane in the stretched operating state brought. This allows even the most stubborn ver blockages and incrustations of the perforations or eliminates porous walls of the elastic membrane will.

Since usually a large number of individual aerator units gate started up next to each other at the same time the short interruption of an individual falls Aerator unit when regenerating it table not weight.

Another advantage of the solution according to the invention is that, in contrast to known aeration tion devices, the maximum length dimensions allow from 1 to 6 meters for a single unit, since with even larger dimensions no uniform Gas distribution is more guaranteed when using a single unit of the method according to the invention can be several hundred meters long without one uneven gas distribution must be feared. This means that the compressed gas can only be fed from one forehead side of a container and does not have to from many individual, over the entire liquid distributed supply lines exist.

By arranging a vortex between the Clamping device and the tubular elastic membrane can even with long lengths the tubular membrane and an incorrect one laying out the tubular elastic membrane be guaranteed that when pulling through the tubular elastic membrane through the ab clamping device no knotting and thus Ver plug the gas supply to the elastic membrane occurs.

The solution according to the invention also enables that by seamlessly juxtaposing individuals membranes or aerator hoses a container  footprint completely and practically without gaps can be fumigated. Such a fumigation has proved to be advantageous in many cases, be especially when above the fumigation facility called static mixer can be attached should. If a part of the sta table mixers formed gaps from below not flowed through with bubbles, so it has in proven in practice that the unavoidable guest gaps with solids from the Block liquid. For example in aerobic, biological wastewater treatment in such spaces anaerobic zones in which Toxins can be formed that are operating can interfere considerably.

With a combination of static mixers with the device for fine bubbles Fumigation of liquids has turned out to be special proven useful that as a support for the mixer z. B. flat iron over the entire Basin length on the floor or above are brought in, which also serve as a guide for the serve individual aerator units, in which Membranes of the aerator units so many perfora tion points exist that under each of the Chambers formed by the mixers is at least one perforation site. One of the like combination of fine bubble ventilation in Connection with static mixers allows that the operation of a unit in the short term can be broken without the overall operation is significantly disturbed, what for the continuous maintaining the flow conditions essential in static mixer is because z. B. in aerobic biological waste water cleaning a short-term change of operations due to drastic changes in biological Lawn that is on the surfaces of the static Mixer forms, has the consequence.

Based on the embodiment shown in the drawing Rungsbeispielen is the basis of the invention underlying thought are explained in more detail. Show it:

Figure 1 is a schematic cross section through a device for fine-bubble Be gases from liquids, which is arranged in a loading container.

Fig. 2 is an enlarged view of the retention tion of a ventilation hose;

Fig. 3 shows a section through the arrangement of Figure 2 in the holder of a single ventilation hose and two ventilation hoses arranged side by side.

Fig. 4 enlarged views of individual parts of the device according to Figures 1 to 3.

Figure 5 is a plan view of a container with a plurality of ventilation hoses arranged in parallel to one another, which are held by tensioning ropes.

Fig. 6 enlarged views of individual parts of the device of FIG. 5;

Fig. 7 shows a cross section through a ventilation tank for a fish farm and

Fig. 8 is a perspective view of a container attachable in the deep part of a fish farming pool or on a flat pool floor.

To explain the function of the device for fine-bubble fumigation of liquids, a cross section through a container is shown in Fig. 1, in which case the container is a pond and with the reference number 1 the pond bottom and with the reference number 11 the pond wall or pond embankment is designated. Approximately parallel to the pond floor 1 and at a short distance from the pond floor 1 , an aeration hose 2 extends over almost the entire width of the pond floor 1 , the aeration hose 2 being laid in a fastening rail 4 , for example a U-shaped rail. On the mounting rail 4 brackets 6 are introduced , which can for example consist of curved round bars and have a distance from each other of about 0.2 to 1 m and prevent floating of the ventilation hose 2 .

In the area of the pond slope 11 , a guide rail 8 is arranged, which is connected to the fastening rail 4 . In addition, 4 rollers 10 and 13 are brought to both ends of the fastening rail, through which the ventilation hose 2 or tensioning cables 12 are pulled over a front reinforcement part, in the exemplary embodiment shown, a swivel 14 . The tensioning cable 12 can optionally be extended by pulling cables, not shown, which are rolled up by means of a crank 16 . The tensioning rope 12 has an eyelet at its end, which can be hooked into a hook 18 attached to the pond slope.

The rear armoring part 26 of the perforated, elastic ventilation hose 2 is connected to a supply hose 3 , via which compressed air is supplied as gas in the exemplary embodiment shown.

As a result of the spaced arrangement of the fixed to the mounting rail 4 brackets 6, the surface of the vent tube 2 at supply of compressed air via the supply tube 3 bulges like a cushion and there occur at the perforation set air bubbles 5 from the ventilation tube 2 and result in a fine-bubble aeration of water in the pond.

In the operating state, the ventilation hose 2 is prestressed by means of the tensioning cable 12 so that the air emerging from the ventilation hose 2 blow 5 give a uniform image and thus lead to a uniform ventilation of the water in the pond. The elongation of the ventilation hose 2 in the operating state is preferably 10% of its rest length before, so that a relatively low tension is exerted on the ventilation hose 2 . When the tension or expansion of the ventilation hose 2 decreases, the tensioning cable 12 can be tightened so that the desired expansion state of the ventilation hose 2 is maintained.

If, due to impurities in the compressed air supplied via the supply hose 3 or due to particles in the liquid, blockages of the perforations in the ventilation hose 2 or a pressure loss to increase as a result of the perforations increase, either the elongation state of the ventilation hose 2 is caused by loosening the tensioning cable 12 and the lifted Belüf tung hose 2 in its rest state length transferred or enhanced elongation of the ventilation tube 2 by tightening the clamping rope or by increased supply of pressurized gas made. When the stretching state is removed, the contaminants at the perforations of the ventilation hose 2 are loosened or blown off as a result of the shrinking process which commences at the same time, so that after a brief release of the stretching state, the operating state can be resumed by tightening the tensioning cables 12 again and thus the ventilation hose 2 is biased by the desired amount. During this cleaning process, the supply of compressed air via the supply hose 3 is not interrupted, so that the liquid in the pond can continue to be aerated.

Alternatively, with increased expansion of the ventilation hose 2, the contaminants can also be blown off, so that after this cleaning process the normal operating state of the relaxed or slightly expanded ventilation hose 2 can be assumed again.

If, however, as a result very resistant Ver blockages of the perforations of the ventilation tube 2 after the cleaning operation is not the desired fine-bubble air bubble distribution resulting image, so it is possible without removal of the breather tube to carry out 2 a further self-cleaning attempt.

For this purpose, the compressed air supply to the ventilation hose 2 is first interrupted and then the stretching state is canceled as previously described. Ventilation duct over a in connection with the illustration of FIG. Shown 4A closer Ent between the supply tube 3 and the ventilation tube 2 is disposed, the pressure air in the ventilation tube 2 from the ventilation tube 2 can escape line via the vent so that the ventilation tube 2 is compressed by the external pressure of the liquid in the pond. The vent line is then closed and compressed air is again supplied to the ventilation hose 2 via the supply hose 3 . Finally, by stretching the tensioning cable 12 , the operating expansion state of the ventilation hose 2 is again established.

In the vast majority of Reinigungsver search can then be found again a fine bubble ventilation of the liquid, so that removal of the ventilation hose 2 is unnecessary. Such a build from the ventilation hose 2 is at most necessary when the elasticity of the ventilation hose slackens, so that there is not the desired fine-bubble air distribution pattern.

The removal of the ventilation hose 2 , however, is particularly easy due to the structural arrangement, since the ventilation hose 2 only has to be pulled out of the guide formed by the fastening rail 4 and the fastening bracket 6 , the possibly longer tensioning cable 12 serving to serve a new one or cleaned or repaired ventilation hose 2 again between the mounting rail 4 and mounting bracket 6 to pull.

The tube in Fig. 2 shown attached to the detailed view of a container base 1 ventilation 2 shows the equidistant zuein other attached mounting bracket 6, which are connected to the container bottom 1 and give a guidance for the ventilation tube 2. Optionally, the mounting bracket 6 on a mounting rail, preferably a U-shaped rail be fastened so that there is a guide channel for the ventilation tubes 2 in connection with the brackets 6 .

In FIGS. 3A and 3B are two different exporting approximately forms the detent of the aeration hoses 2 in a section AA according to FIG. 2.

Fig. 3A shows the mounting of a single Belüf tung hose 2 by means of an immediately hälterboden to Be fixed to the mounting bracket 61, while in Fig. 3B, two ventilation tubes 2, by means of a W-shaped bracket 63 which is fixed to a mounted in the container bottom 1 bar 4 be locked.

In Fig. 4, several details for the fastening supply of the ventilation hoses 2 in the container shown in Fig. 1 are shown.

Fig. 4A shows on an enlarged scale the connec tion of a ventilation hose 2 with a supply hose 3rd The connection is made by means of a Armie approximately member 26 fitted on the one hand, the supply hose 3, and on the other hand, the perforated elastic aeration tube 2 and fixed ring, as required by means of additional fastening. The reinforcement part 26 has guide rings 22, the iron round guide 36 are plugged and iron from the guide are guided round 36th On the armoring part 26 , a drainage and ventilation line 24 is introduced , which preferably has automatic valves for a possible water drain.

Fig. 4B shows a partial view BB of FIG. 1 of the guide of the ventilation hose 2 in the area of the rear armoring part, the guide being produced by means of a guide roller 10 which is supported in the U-shaped fastening rail 4 .

Fig. 4C shows the arrangement of the ventilation hose 2 in the supply rail formed by the U-shaped fastening 4 and a mounting bracket 61 ge formed guide channel according to partial view CC in Fig. 1st

Fig. 4D shows a single view of the design and arrangement of the roller 13 for passing the train and tensioning cable 12, the roller 13 similar to roller 10 in the U-shaped mounting rail 4 is supported.

Fig. 4E shows a detailed view of the fastening of the tension cable 12 by means of an eyelet 20 which is suspended in a hook 18 . A crank 16 is used to tension the tensioning cable 12 .

Fig. 4F illustrates the assembly and connexion of the ventilation hoses 2 with the tension cables 12 and the reinforcing parts 26th In the illustrated embodiment, two ventilation hoses 2 are connected to a reinforcing part 26 , which is fastened by means of rings 22 to a guide rod 36 . This rear arming end has a ventilation and drainage opening 25 , to which a corresponding ventilation and drainage line can be connected. Via the compressed gas opening 27 , the ventilation hose 2 is supplied with gas.

The front armoring part 23 is provided with a hook 27 , to which a tensioning cable 12 is fastened, the opposite end of which has an eyelet 20 .

Instead of a connection of two ventilation hoses 2 on the front armoring part accordingly speaking armouring parts 31 can be provided, each of which has hooks 29 , to each of which a tension cable 12 is fastened, which, analogously to the embodiment described above, has a form at the other end Has eyelet in which a corresponding tension hook engages. Finally, instead of the front reinforcement part, the ventilation hose, which is completed in each case, can be connected via a swivel 14 to a tension cable 12 in each case.

The arrangement of the vortex 14 proves to be both highly agitated liquid as well as for greater lengths of the venting tube 2 to be very advantageous. This allows, for example, when replacing a ventilation hose 2 a self-unordered ventilation hose 2 under the Abspannvor directions over its full length who who without eliminating twists or knots beforehand. If gas is then supplied to the ventilation hose 2 under pressure, an automatic extension of the ventilation hose 2 occurs as a result of the vortex 14 without the risk of knots forming and thus obstructions to the gas distribution within the ventilation hose 2 .

FIG. 4G shows a side view of the reinforcement part 26 shown in a top view in FIG. 4F. This side view illustrates the structural design of the armoring part 26 and the arrangement of the drainage and ventilation line 24 and the rings 22 for connection to a guide round iron.

Fig. 4H shows a side view of a front reinforcing member 23 , each of which connects two adjacent ventilation hoses 2 ver.

The reinforcement part 31 shown in Fig. 4I serves to connect only one ventilation hose 2 with a corresponding guide round iron, which is inserted through the guide rings 22 .

Fig. 4K shows a detailed view of a vertebra 14 for connecting a reinforcement end part with a tension cable or for directly connecting the closed end of a ventilation hose 2 with a tension cable 12 .

In Fig. 4L to 4O more Einzelhei finally are th in terms of the structural design of the hook 18, which receives the on the rope one end of the instep formed lug 20, the roller 13 for receiving and guiding the tension cables, of the guiding round bar 36 and the Connection of the hook 18 with the eyelet 20 shown.

The plan view shown in Fig. 5 on a ventilation basin shows a plurality of parallel and equally spaced ventilation hoses 2 , which are arranged evenly distributed over the pool floor 1 .

In the illustrated embodiment, each weils five ventilation hoses 2 are summarized in a Armie inferring section 26, wherein the individual reinforcing parts 26 distribute the hose supplied via a supply of compressed air to the five ventilation hoses. 2 In addition to the compressed air supply opening 27 , a drainage and vent opening 25 is provided, which serve for dewatering and venting the ventilation hoses 2 . The reinforcing parts 26 each have two guide rings 22 which can be placed over guide rods 36 and can be moved on the guide rods 36 . As a result, the reinforcement parts can be pushed down to the pool floor or to a desired distance above the pool floor or pulled up to the water surface.

At the opposite ends of the ventilation tubes 2 rollers 13 are arranged, over which the tensioning ropes, not shown, are placed. Vertebrae 14 are provided between the rollers 10 and the ends of the ventilation tubes 2 .

Transverse to the tensioning direction of the ventilation hoses 2 , tensioning ropes 60 are provided at the same distance and parallel to one another and are fastened to the pool wall 11 by means of eye bolts 30 . In addition, further eyebolts 28 are provided, which are fastened at equal intervals to one another in the pelvic floor 1 . Thus, the tension cables 60 are used in conjunction with the inserted into the pelvic wall 11 eyebolts 30, and the bottom in the basin eyebolts 28 as Fixed To supply stirrup for locking the ventilation tubing. 2

As can be seen from this illustration according to FIG. 5, it is a relatively simple arrangement and attachment of the ventilation hoses 2 in the area of the pool floor 1 for fine-bubble ventilation of the water in the pool. When any required replacement of a ventilation tube, the associated reinforcement part 26 is drawn to the water surface at ge loosened tension ropes, loading respective drawn breather hose 2 abge from the reinforcement part 26 and taken out of the basin. Subsequently, a new or the cleaned ventilation hose 2 can be fastened to the vertebra 14 and, when the armoring part 26 is lowered, the tensioning cable in question can be drawn in, so that the ventilation hose 2 is pulled under the tensioning cables 60 to the opposite side of the pelvis. Subsequently, all the ventilation hoses 2 assigned to the relevant reinforcement part 26 can be brought into the predetermined stretched state again by tensioning the tensioning cables.

FIG. 6 shows further details of the device for fastening and tensioning the ventilation hoses according to FIG. 5.

In detail, FIG. 6A, the embodiment of a pelvic floor to be fixed ring screw 28, whereas Fig. 6B shows the embodiment of a pool wall to be fastened in the screw ring 30 to which the tensioning cable in question can be attached. The larger distance between the plate resting on the basin to the eyelet for receiving the tensioning rope compared to the short distance of the eyebolt 30 according to FIG. 6B serves to keep the tensioning rope floor at a certain distance from the basin, so that the relevant ventilation hose or the ventilation hoses can be pulled through.

FIG. 6C shows a top view and FIG. 6D shows a side view of the rollers 13 which are used for pulling through or pulling through the pulling and tensioning cables and are fastened to one of the pool walls.

Fig. 6E shows the arrangement of ring screws 30 on the pool edge 11.

Fig. 6F shows the arrangement of the hooks 18 and 20 eyelets at the end of the tensioning cables, which are fastened to the pool edge.

Fig. 6G shows a plan view and Fig. 6H is a side view of be fixed on a common rail guide round bar 36 , about the corresponding guide rings for receiving the armature tion parts are inserted.

A corresponding armoring part is shown in Fig. 6I, which has five connecting pieces for loading five ventilation hoses. The compressed air supply opening 27 serves to receive the supply hose 3 , while the ventilation and drainage opening 25 is used to receive a corresponding ventilation and drainage hose 24 . Two guide rings 22 each serve to lock the relevant reinforcement part 26 .

Fig. 6K shows a side view of the reinforcement part of FIG. 6I.

Fig. 7 shows a cross section through a fish farming tank 50 , in which a device for fine-bubble aeration of the water in the fish farming pool is used in conjunction with a static mixer formed as a container. The fish farming basin 50 has a substantially horizontal basin bottom 52 which preferably merges centrally into a shaft-shaped part which has sloping basin walls 53 . The basin walls 51 provided in the upper part of the fish farming basin 50 have drainage holes at the level of the water level, through which water can flow into a drainage channel 54 . The shaft-shaped part of the pool floor is supported on a foundation 62 and has in its lower channel-shaped part a clearing chain 56 , with the aid of which sludge, which settles in the V-shaped pool recess, is transported to a pool end, where it can run off or is subtracted.

The device for fine-bubble aeration of the water in the fish farming pool 50 is preferably located in the upper third of the V-shaped pool recess and, analogously to the embodiments described above, consists of perforated, elastic ventilation hoses 2 which are arranged between vertically arranged guide rods 40 . Above the guide rods 40 are transversely extending mounting rods 42 are arranged, through which the ventilation hoses 2 are prevented from operating and which, together with the guide rods 40, result in a channel for receiving the ventilation hoses 2 .

Above the mounting rods 42 packs 44 are arranged, which are accommodated together with the device in the ventilation device 70 , which is completed by side container walls 72 . The packs 44 are preferably designed as so-called static mixers and, in conjunction with the ventilation device, result in a mammoth pump effect by which the currents entered with arrows are caused.

Both on the container walls 72 and in the connection of the substantially horizontally running basin bottom 52 with the V-shaped recess, grids 48 are attached which prevent the fish in the fish breeding tank 50 from entering the shaft with the packs 44 or to swim in the V-shaped recessed part of the fish tank 50 .

In addition, in the recessed part of the pelvic floor arranged cross struts 58 are used for static fastening of the V-shaped deep part, with extensions of the transverse to the guide rods 40 duri fenden mounting rods 42 also serve for bracing and at the same time for carrying the packs 44 and container 70 .

The ventilation hoses 2 are connected to the respective end faces with front or rear reinforcement parts analogous to the exemplary embodiments described above, via which compressed air is supplied on the one hand and on the other hand the necessary pretension for stretching the ventilation hoses 2 is produced. The ventilation hoses 2 have at least as many perforations that under each of the openings that are formed by the static mixer in the vertical direction, at least one hose perforation is easily seen.

FIG. 8 shows a perspective view of the container shown in FIG. 7 and illustrates its structural design.

In the lower part of the container 70 consists of the longitudinal and lateral guide serving the ventilation hoses serving guide rods 40 , over which the transverse fastening rods 42 are arranged. The fastening rods 42 are connected to the container walls 72 which have reinforcing plates 74 running vertically. The reinforcement plates 74 are interconnected by means of longitudinal rails 82 and have outflow baffles 76 in the upper part.

The outflow baffles 76 can also be before devices for receiving sieves u. Include.

The surface of the container 70 is formed by the con tainer walls 72 connecting strut rails 78 on which the playpen 80 can be placed.

Such a container 70 can be attached both in the deep part of a fish farming basin and on a flat basin floor. Furthermore, several containers 70 can be arranged one behind the other, so that the creation of appropriate systems, which is composed of individual structures, he is possible.

Claims (23)

1. A method for the fine-bubble gassing of a liquid, in which the gas enters a liquid through a porous or perforated, elastic and essentially horizontally oriented membrane and in which a tensile force can be applied to the membrane at least on two opposite sides, and thus the membrane can be put into a stretched state, characterized in that the tensile force on the membrane and thus its stretched state can be changed and that the membrane is guided on at least one horizontal guide device. 2. The method according to claim 1, characterized in that the elastic membrane ( 2 ) is tubular and that the position and / or the state of expansion of the membrane ( 2 ) is changed in the direction of the longitudinal extension of the membrane ( 2 ). 3. The method according to claim 1, characterized in that the elongation state of the elastic membrane ( 2 ) is changed in the transverse direction with the position of the holding devices unchanged by increased, reduced or interrupted gas supply. 4. The method according to any one of the preceding claims, characterized in that the elastic membrane ( 2 ) is stretched in the operating state in the longitudinal direction by a predetermined, fixed amount, preferably by 15% to 25% compared to its dimensions in the idle state. 5. The method according to any one of the preceding claims, characterized in that the stretching of the elastic membrane ( 2 ) in the longitudinal direction depending on the gas pressure on one side of the elastic membrane ( 2 ) is carried out. 6. The method according to claim 5, characterized in that the elongation of the elastic membrane ( 2 ) in the longitudinal direction depending on the difference between the gas pressure on one side of the elastic membrane ( 2 ) and the liquid pressure on the other side of the elastic membrane ( 2 ) is made. 7. The method according to claim 1 or 2, characterized in that the stretched in the operating state in the longitudinal direction elastic membrane ( 2 ) for cleaning the gas supply interrupted, inside the membrane ( 2 ) residual gas and liquid via a drainage and ventilation line ( 24 ) is released that the stretching of the elastic membrane ( 2 ) in the longitudinal direction is canceled, that after a predetermined time the elastic membrane ( 2 ) is stretched again, and that gas is subsequently introduced into the elastic membrane ( 2 ) again. 8. The method according to claim 1 or 2, characterized in that the relaxed in the operating state in the longitudinal direction elastic membrane ( 2 ) for cleaning gas under increased pressure and / or tension on the elastic membrane ( 2 ) is applied for stretching, and that then the gas supply is brought to a value corresponding to the operating state and / or the tensile force exerted on the elastic membrane ( 2 ) is reduced or eliminated. 9. Device for fine-bubble gassing of a liquid with a container for holding the liquid, with a porous or perforated, elastic and essentially horizontally aligned membrane to which the gas is supplied and through which the gas passes to enter the liquid and with at least two holding devices for holding the membrane on opposite sides, with the holding devices exert a tensile force on the membrane and so the Put the membrane in a stretched state characterized, that in the area of at least one end of the membrane a horizontal aligned guide device is arranged on which the Membrane slidably abuts that the holding device in the connection is arranged on the guide device and that of the Holding device applied traction can be changed in size is, so that the elongation state of the membrane can be changed is.   10. The device according to claim 9, characterized in that the elastic membrane ( 2 ) is connected to a device ( 24 ) for discharging gas and liquid. 11. The device according to claim 9 or 10, characterized in that the elastic membrane ( 2 ) is self-contained and arranged in the region of the bottom of the liquid container and that at least a portion of the upper side of the elastic membrane ( 2 ) facing the liquid surface is perforated, preferably is perforated, slotted or provided with cross-slits or is porous. 12. The device according to claim 11, characterized in that a device for measuring the gas pressure is arranged in the interior of the elastic membrane ( 2 ) and that a device is provided which in about the holding devices ( 12, 14, 16, 18, 20 ) The expansion measure changes depending on the gas pressure. 13. Device according to one of the preceding claims 9 to 12, characterized in that the elastic membrane ( 2 ) consists of at least one porous or perforated ventilation hose ( 2 ) which is held horizontally by means of the guide device ( 6; 60 ), and that Guide device consists of weights attached to the underside of the porous or perforated ventilation hose ( 2 ). 14. The apparatus according to claim 13, characterized in that the guide device consists of bracing devices ( 6; 60 ) arranged transversely to the longitudinal direction of the ventilation hose / ventilation hoses ( 2 ), under which the ventilation hose / ventilation hose ( 2 ) are freely movable. 15. The apparatus according to claim 14, characterized in that the guy devices from mounting rails ( 4 ) connected mounting brackets ( 6; 61, 63 ), the ventilation hose / the ventilation hoses / the ventilation hoses ( 2 ) extending at predetermined intervals from each other, on the container bottom ( 1 ), on the container wall or in a container attached mounting rails ( 6 ) serve as guide rails. 16. The apparatus according to claim 14, characterized in that the guy devices from transverse to the longitudinal direction of the ventilation hose / the ventilation hoses ( 2 ) extending tension cables ( 60 ), which are fastened by means of eyebolts on opposite pool edges ( 11 ) and by means of further eyebolts ( 28 ) are spaced from the pool floor. 17. Device according to one of the preceding claims 9 to 16, characterized in that in the region of the container wall ( 11 ) deflection devices ( 10 ) are arranged, via which the ventilation hoses ( 2 ) are lowered into the liquid container or can be removed from the liquid container . 18. Device according to one of the preceding claims 9 to 17, characterized in that the / the ventilation hoses ( 2 ) between parallel to the / the ventilation hoses ( 2 ) extending, vertically arranged guide rods ( 40 ) are arranged and that above the guide rods ( 40 ) and transverse to the guide rods ( 40 ) extending fastening rods ( 42 ) are arranged, which together with the guide rods ( 40 ) result in a channel / channels for receiving the ventilation hose (s) and that the guide rods ( 40 ) and the fastening rods ( 42 ) den form the lower part of a container ( 70 ), which is laterally closed by container walls ( 72 ) and in which packs ( 44 ) designed as static mixers are arranged. 19. The apparatus according to claim 18, characterized in that the / the ventilation hoses ( 2 ) has / have at least as many perforations that under each opening, which are formed by the static mixer in the vertical direction, at least one perforation is provided. 20. Device according to one of the preceding claims 9 to 19, characterized in that between the elastic membrane ( 2 ) or the / the ventilation hoses ( 2 ) and the holding device ( 12, 14, 16, 18, 20 ), a vortex ( 14 ) is arranged so that a torque is not transferable. 21. The apparatus according to claim 20, characterized in that the guide rods ( 40 ) and the fastening rods ( 42 ) form the lower part of a container ( 70 ) which is laterally closed by container walls ( 72 ) and in which packs designed as static mixers ( 44 ) are arranged. 22. The apparatus according to claim 21, characterized in that the / the ventilation hoses ( 2 ) has / have at least as many perforations that under each opening, which are formed by the static mixer ge in the vertical direction, at least one perforation is seen easily. 23. The device according to claim 10, characterized in that a vertebra ( 14 ) is arranged between the elastic membrane ( 2 ) and the tensioning device ( 12 , 14 , 16 , 18 , 20 ).