WO1998007662A1

WO1998007662A1 - Bioreactor

Info

Publication number: WO1998007662A1
Application number: PCT/EP1997/004481
Authority: WO
Inventors: Wolfgang Schenk
Original assignee: Wolfgang Schenk Gmbh
Priority date: 1996-08-19
Filing date: 1997-08-16
Publication date: 1998-02-26
Also published as: CZ53999A3; EA199900213A1; NO990764D0; CA2263668A1; HUP9903778A3; EP0944553A1; SK19699A3; PL331855A1; JP2000503896A; AU4205497A; HUP9903778A2; NO990764L; EA001562B1

Abstract

In a bioreactor (8) for conditioning water loaded with organic substances, in particular from car washing installations, the reactor container has a solid bed (48) made of a porous substrate material capable of adsorbing the organic substances contained in the waste water and sown with micro-organisms known per se which degrade the organic substances contained in the water. The solid bed (48) is located on a permeable substrate (47) and a water collecting chamber (46) is provided below the solid bed, upstream of the outlet for the treated water. The outlet (26) is at the same time designed as a backwashing inlet. An inlet (24) and a backwashing outlet (28) are provided above the solid bed (48).

Description

"Bioreactor"

description

The invention relates to a bioreactor for the treatment of water contaminated with organic substances, in particular from car washes, in which the reactor vessel has a fixed bed which consists of a porous carrier material which is adsorbable and porous for the organic constituents of the waste water and which is known per se, the organic constituents of water-degrading microorganisms is populated.

It is known to treat the washing water from car washes before being discharged into the municipal sewer system by using drainage systems in accordance with DIN 1986 and DIN 1999 so that they meet the requirements of the legislature and the municipal administrations. The washing waste water from car wash systems is then mechanically cleaned in a sludge trap, largely freed from mineral oil hydrocarbons in a light liquid cutter, collected in a storage basin and fed into the sewage system via a control shaft. Further stages, such as chemical and / or biological treatment, can be included in the washing wastewater treatment and serve to reduce the fresh water requirement.

According to DE-A-26 51 483, the washing waste water from a vehicle washing system, which biodegradable cleaning and care products and solid substances contains, cleaned by adding a polymeric flocculant to the wastewater and first passing it through a sedimentation zone with reduced water flow and then through an adsorbent.

DE-C-41 16 082 describes a method of water treatment in car washes, in which the wash water obtained is mechanically or mechanically and biologically cleaned and returned to the washing system. The solids resulting from mechanical cleaning are collected in waste batches requiring disposal. The pollutants are mechanically or biologically processed in a multi-stage process in such a way that solids with hydrocarbons and pollutants from the wastewater coming from the car wash are separated and collected in a first cycle, so that when collecting the hydrocarbons and pollutants with washing substances containing wastewater are extracted from the washing zone and that the mechanically clarified wastewater is freed from non-degradable components in a second circuit by flotation and by biological reaction.

The common disadvantage of the known methods is that the washing waste water has to be processed in complex multi-stage processes. The resulting solids, usually flotates and sand and sludge washed off the vehicles, have to be disposed of as special waste batches. The water and the solids accumulating in the system are contaminated with odor, which can be extremely and annoying. The reuse of the cleaned washing water requires a high proportion of fresh water. The excess water is fed into the municipal wastewater treatment system via a sewer connection. It has been shown that these shortcomings are mainly due to an ineffective biological treatment of the wash water. The invention is therefore based on the object of increasing the effectiveness of the biological treatment of the washing waste water for complete reuse. The preparation must be able to be resumed without problems even after periods of low washing activity. This is to be achieved by providing an effectively working bioreactor that is tailored to the requirements in treatment plants for car washes.

The object is achieved with a bioreactor of the type mentioned at the outset, in which the fixed bed is located on a permeable support, a water collection space is provided below the fixed bed, which is connected upstream of the outflow for the treated water, the outflow being simultaneously designed as a backwashing inlet and an inlet and a backwash outlet are provided above the fixed bed.

Preferred embodiments are the subject of the dependent claims.

The bioreactor according to the invention is filled with a fixed bed material which is suitable for adsorbing mineral oil hydrocarbons and car care products, and also has a porosity and surface which requires the settlement of microorganisms. These colonization zones are necessary so that the bacterial turf that forms is not torn off by the shear forces of the water flowing through and is carried away from the system.

A water collection space is formed below the fixed bed and separated from the fixed bed by a permeable support, such as sieve gauze, so that the fixed bed material is not discharged from the working zone. From this water collection chamber, the water is either pumped sideways through the tank wall or upwards through a specially inserted pipe. The inlet and outlet is designed by inlet and outlet spiders so that a uniform water distribution and uniform flow behavior is achieved both in normal operation and during backwashing.

When the bioreactor, which has to be flushed out from time to time, is backwashed, suspended matter and excess microorganisms are removed from the reactor vessel in order to maintain permeability. Backwashing takes place in countercurrent from bottom to top using a specially designed flushing and overflow device. This flushing and overflow device has a cross-section which tapers towards the top, which leads to a narrowing of the free reactor cross-section and brings with it a higher flow rate of the backwashing stream. The higher flow rate of the backwashing stream is suitable for completely removing floating suspended matter from the inlet area.

Introduced measuring probes for the detection of the filling level for the flow regulation and the dry run protection of the pumps are integrated in the control system into the entire system of the treatment plant and allow the necessary adaptation to the different operating conditions during washing times and ensure in particular the regular backwashing and an automatic night run as well as the automatic fresh water replenishment.

The bioreactor according to the invention is used in a process which has a mechanical and a biologically working treatment stage. The mechanical treatment stage consists of the sludge trap, in which there is sedimentation of the coarse dirt carried along. In general, these are mineral particles, but are often contaminated by mineral oil products. Coarser mineral oil particles, for example from the wax or underbody protection of a motor vehicle, also get into the sludge trap. A considerable amount of biological processing of the sludge load takes place in the sludge trap. Due to the backwashing of the filter system and the bioreactor described later, mineral oil-degrading microorganisms repeatedly enter the sludge trap, which settle there and fulfill their purpose. In this way, a large part of the organic load of the sludge trap is decomposed by the microorganisms. Experience to date has shown that the content of the sludge trap decomposes to a humus-like mass after a few months, which is no longer contaminated with mineral oil components and can be disposed of with household waste without any problems.

After passing through the sludge trap, the waste water enters a storage basin which essentially serves as a buffer and from which water is continuously pumped through a filter system into the bioreactor according to the invention. The buffer effect of the storage basin has two aspects, firstly a quantity aspect, since a continuous wastewater flow must be delivered to the bioreactor even when the frequency of use of the car wash system changes. On the other hand, the storage basin also serves as a dilution basin for highly concentrated dirt loads that arise when cleaning particularly dirty motor vehicles or those contaminated with special pollutants.

The filter system is a conventional filter for removing suspended matter, which consists, for example, of several alternating layers of coarse and fine gravel fillings. The suspended matter filter can be flowed through with or against gravity by the waste water and has to be backwashed with clean water every now and then or replaced. The filling of the particulate filter is conveniently stored on perforated plates or the like, under which the outlet is located. The bioreactor according to the invention connected downstream of the suspended matter filter is traversed by gravity from the waste water and accommodates on its carrier material the microorganisms which break down the dirt load in the waste water which occurs in a car wash. These are generally aerobic bacteria that are known per se and can also be obtained using known selection mechanisms.

The pure water emerging from the bioreactor is then collected in a pure water tank and from there it is reused in the car wash.

It goes without saying that the constant loss of circulating water through evaporation and discharge through washed motor vehicles must be countered by feeding pure water. It has been shown in a test facility that several 10,000 cycles can easily be achieved with the wastewater treated and supplemented in this way.

The bioreactor consists of a fixed bed made of a porous carrier material that can adsorb the organic constituents of the wastewater and provides the necessary microorganisms with sufficient support for settlement. The microorganisms form a lawn on the surface of the carrier material and in the pores, which filters the sewage flowing past and absorbs the dirt contained therein. The adsorption effect of the carrier material demands this effect by supplying the components adsorbed from the wastewater to the microorganisms.

In order to ensure sufficient permeability of the fixed bed for the washing water, the porous carrier material is expediently in the form of a pouring bed which, apart from the pure pore space, offers additional space between the individual carrier particles. Suitable porous Support materials are, for example, coal, clay, silica gel or zeolites in pelletized form or else foam plastic flakes with a sufficiently large pore volume, for example made of polyurethane, polystyrene or the like. A particularly suitable material has, for example, a particle size of 1 to 10 mm, a vibrating density of 0.25 to 1.0 g / cm ³ , a pore volume of 0.40 to 1.0 cm ³ / g and a surface area of more than 500 m / g. However, other materials with comparable physical properties can also be used.

It is understood that the bioreactor must be backwashed regularly to prevent it from clogging with suspended particles or from being blocked by excessive bacterial growth. The bioreactor is backwashed in such a way that the rinsed-out materials are carried back into the sludge trap, where the mineral oil-degrading bacteria washed in there can in turn act.

It is expedient to keep the bioreactor in operation via a so-called night run even in times of low washing frequency. For this purpose, pure water is expediently returned to the storage tank and from there via the suspended matter filter into the bioreactor. The circuit ensures a regular flow through the bioreactor and thus also a regular supply of nutrients from the storage. At the same time it is achieved that the dirt load contained in the storage basin is slowly broken down overnight, which means that the new wastewater supply on the next day is first diluted with relatively clean storage basin water and a sudden impact on the microorganisms is avoided.

As already mentioned, the bioreactor is operated aerobically. The amount of oxygen contained in the wash water is usually not sufficient for this. It is therefore advisable to introduce oxygen or air into the bioreactor, expediently via an air injector. For this purpose, part of the water running out of the bioreactor is branched off, saturated with air and returned to the bioreactor. However, it is also easily possible to return water from a pure water tank to the bioreactor that has previously been saturated with air.

A pure water tank collects the pure water running out of the bioreactor and makes it available for reuse in the washing cycle. A sufficiently large volume ensures that sufficient water is available both for cleaning purposes and for the treatment process (backwashing, after-running). The pure water delivered to the washing system can first be sterilized by disinfection, for example with the aid of UV radiation.

It goes without saying that the care products used in the washing process have no biostatic or biocidal constituents and are completely biodegradable. The rate of biodegradation must be taken into account when dimensioning the processing plant; The faster the degradability, the smaller the storage basin, the bioreactor and the clean water tank can be designed within certain limits. It has been shown that for an average car wash, sludge trap and storage basin as well as clean water tank should have a collection volume of 6 m and the filter unit and the bioreactor have a capacity of 1 to 1.5 m ^3. The materials used for all lines and containers are both Corrosion-resistant metals as well as plastics that meet the requirements, in particular glass-fiber reinforced plastics or HDPE.

In general, the washing waste water obtained in a washing plant is fed to a storage basin via a sludge trap known per se and from this via a suspended matter filter aerobically operated bioreactor. The The carrier material of the fixed bed is porous, has a large specific surface area, can adsorb water contents and serves for the settlement of special microorganisms. The water in the reactor is constantly circulated by means of a circulating pump and enriched with a suitable device, preferably an injector, without pressure with oxygen, preferably atmospheric oxygen from the surrounding atmosphere. The circulation speed can be varied within a wide range. It must be dimensioned so that the biofilms are not damaged. The washing waste water arrives from the biroeactor via an overflow control in a pure water tank. From here it is fed back to the washing process 100%, possibly via a disinfection system.

Backwashing of the bioreactor becomes necessary when the pressure difference between the inlet and outlet of the suspended matter filter or the reactor vessel reaches a limit value as a measure of the load due to retained suspended matter or excess biology, for example 0.5 bar.

It has also been shown that the bioreactor according to the invention is suitable for taking up and treating contaminated water from the workshop area and petrol pump area of a petrol station. It is therefore understood that such additional wastewater can be used in addition to the wastewater generated in the car wash. In this respect, the bioreactor according to the invention is suitable for replacing the systems for treating rainwater required for petrol stations. Otherwise, the reactor according to the invention can also be used advantageously in other ways.

Regularly one chooses for the reactor vessel because of its load, above all because of the content of waste water after the optimal container design for such static loads in vessel and apparatus construction as a cylinder with a preferably curved base and lid and from metal sheets in welded constructions. For many applications of the invention Bioreactor and for example for wastewater treatment plants of car washes, however, such containers are not optimal. In these and other applications of the invention, the reactor vessel and, if applicable, the assemblies of the processing plant which interact with it must be accommodated in a closed space which is preferably optimally arranged directly next to the car wash in car washes. Due to the limited room heights, the resulting wastewater volumes have cylinder diameters that are larger than the usual door openings, but which are a requirement on site. Since the usual cylindrical containers do not fit through such door openings, in practice one regularly helps oneself in these cases by breaking out a sufficiently large assembly opening in one of the room walls through which the reactor container fits; after its erection, this breakthrough must be closed again. The associated effort and the inevitable danger to the statics of the installation building represent an extraordinary disadvantage.

According to the invention this is remedied and a cheaper solution is created for the treatment plants with a bioreactor, which can be used for all wastewater capacities. According to the basic idea of the invention, as set out in claim 12, the plan of the reactor vessel adheres to the on-site specifications in a predetermined area dimension, that is, in the example given, corresponds to the mostly standardized door opening of the exhibition space, which is used as the basic size in the plan of the vessel according to the invention can be. Since the room heights are also generally determined on the building side and on the other hand by the wastewater capacity of the treatment plant itself, this results in the other area dimension of the reactor vessel and thus a reactor vessel, which forms the module of a modular system that forms the wastewater volume of a concrete wastewater treatment plant with one or more modules , ie containers connected in parallel, coped. The invention therefore has the advantage that it allows the client in the choice of the building and in particular in the choice of the area dimension of the installation of the processing plant, a wide range of design freedom and does not require any final or temporary changes to the structure to adapt to the assembly and installation of the reactor vessel .

In practice, it has been shown that embodiments of the invention according to claim 13 are best suited for the shaping of the reactor vessel in order to meet the on-site requirements. If one takes the standardized door opening of 80 cm as a basis, one usually comes to an almost square, square floor plan, although of course other floor plan forms are also possible in order to take advantage of the invention. In the intended case, the shorter side of the rectangle is the area dimension of the container floor plan that is predefined on site.

Apart from on-site specifications, the container specifications resulting from the load on the reactor vessel can also be met with vessel shapes that do not correspond to the usual cylindrical shape. This is in the claim

14 reproduced. Surprisingly, it has been shown that a container made of thermoplastic material, because of its welded construction from flat plates, has sufficient inherent rigidity to remove the mainly static loads of the container filling, in particular with waste water, essentially without deformation. This is achieved in particular by so-called HDPE plastics, which are the subject of the claim

15 are.

The flat walls and bottom of such a container also have another advantage. The number of containers resulting from the modular system can be set up wall to wall in a space-saving manner. That applies even if only one module is used for such a system. Because the polygonal floor plan can be accommodated in given building floor plans better than the usual circular cross section of containers. The wall-to-wall arrangement of several modules therefore makes optimal use of the space available for standard room layouts, especially if the container layout is rectangular to square. It is then advisable, however, to make use of the features of claim 16, since the optimal assignment of several modules of the modular system with a base frame is thereby forced.

The invention is illustrated by the following figures. Of these shows

Fig. 1 shows schematically an embodiment of the bioreactor according to the invention

FIG. 2 shows the integration of the bioreactor according to the invention according to FIG. 1 into an overall system for wastewater treatment

Fig. 3 details of a preferred embodiment of the backwashing process of the bioreactor according to the invention

Fig. 4 shows a schematic representation of the arrangement of two modules and

5 shows a section along the line V-V of FIG. 4th

1 consists of the reactor vessel 8, which in turn is divided into three sections, a lower water collection space 46, the fixed bed 48 and an upper inflow space 49. A permeable support is located between the lower water collection space 46 and the fixed bed 48

1 9 47, for example made of sieve gauze or a perforated plate, which reliably prevents the fixed bed filling from passing through. A delimitation of the upper inlet space 49 from the fixed bed 48 is only necessary if the fixed bed filling consists of a specifically light material that floats in the backwashing stream under normal conditions. In this case, a water-permeable membrane can also be drawn in there.

The water to be treated passes through lines 27 and 29 to the distribution spider 24 in the upper inlet space 49. After passing through the fixed bed 48, it is drawn off from the lower water collection space 46 via the extraction spider and the line 30 by means of a pump 31. The pure water from line 30 is mixed with air via line 32 and injector 10 before it passes through valve 35 into a clean water tank.

A portion of the water from line 30, after it has been enriched with air via injector 10, is fed via valve 34 and line 33 back into line 29 and bioreactor 8 in order to cover the oxygen requirements of the microorganisms there.

The line pressure within the system is constantly monitored; a pressure measuring point 40 determines the pressure in line 30 and is used to calculate the differential pressure between inlet and outlet from the bioreactor δ. If the pressure in the line 30 drops relative to the inlet pressure, which indicates a clogging of the fixed bed, the backwash system is activated, in which, after opening and closing the corresponding valves via line 17, pure water is pressed into the discharge line 30, which causes the Flow direction reversed. The pure water passes through the spider 26 into the lower collecting space and presses from below through the fixed bed 48 into the upper distribution space 49, from where it passes over the overflow

28 and the line 14 is led into a sludge trap. The feed line 27 or

29 via the spider 24 is closed in this case. A fill level control 25 with various measuring points serves to monitor the water level in the bioreactor 8 and is connected via a control line S to the pump 31 and a control center. In normal operation, the water level is constantly kept between the two measuring points in the upper inlet space 49. Another measuring point in the lower collecting space 46 is required if the fixed bed 48 is driven dry for maintenance or for other reasons.

Fig. 2 shows the overall process. The same numbers denote the same positions. The dashed lines indicate control lines for operating the system.

The wastewater from the washing plant, a workshop or the surface drain water of a gas station area comes via the feed line 1 into the sludge trap 2, where the sedimentation of the coarse dirt takes place. The line 21 continues into the storage basin 3, which serves as a buffer for the wastewater freed from coarse dirt. In the reservoir 3 there is a level control 4 with an upper and a lower switching point.

The water from the storage basin 3 is fed through the line 22 into the suspended matter filter 7 via a suction body 5 and the feed pump 6, which form a unit in the present embodiment. A line 23, which is secured by a valve, allows the sampling of dirty water from line 22.

The water from the storage basin 3 enters the suspended matter filter 7 via a distribution spider 24. The filter is filled with alternating layers of coarser and finer gravel, which the sewage traverses from top to bottom. Via a spider 26, the filtered waste water is pumped through line 27 with the aid of pump 9. A fill level control 25 prevents this Dry running of the filter device, but also has a lower switching point with which the filter device can be more or less completely emptied. An overflow 28 leads via line 14 back into the sludge trap 2 and is required in the case of backwashing the filter 7.

The water withdrawn from the filter via the spider 26 reaches the bioreactor 8 via the line 27 and the pump 9 as well as the line 29, where it is applied to the surface of the porous carrier material therein, expediently activated carbon pellets with a large pore volume and sufficient empty space between the individual particles. The porous carrier material is populated with the microorganisms conditioned on the organic dirt load of the wastewater. The waste water passes through the fixed bed of the bioreactor from top to bottom and is fed to the clean water tank 11 via the spider 26 of the bioreactor 8 via the line 30 with the aid of the pump 31. A fill level control 25 ensures, corresponding to the suspended matter filter 7, that the bioreactor 8 is adequately filled.

An injector switched on in line 30 injects air drawn in via line 32 into the water drawn off from bioreactor 8. The water saturated with air is fed via a line 30 to the clean water tank 11, but also partially returned via line 33 to the bioreactor, where it ensures an adequate oxygen supply to the reactor and the microorganisms. Solenoid valves 34 and 35 ensure the correct distribution ratio of air-saturated water between bioreactor 8 and pure water tank 11. However, batch-wise operation of bioreactor 8 is also possible, in which a circuit through line 33 takes over the air supply. Only the completely clarified water is added to the tank 11.

The pure water tank 11 receives the biologically clarified water from the bioreactor 8. A level control 36 ensures that the clean water tank is filled with a sufficient amount of water to the To be able to maintain the washing operation as well as the night cycle operation. In the event that there is too little water in the circuit, fresh water can be supplied via line 12.

The water is drawn off from the pure water tank 11 via the line 37 with the aid of the pump 15 and fed to the running line 13 into the washing system. A disinfection system 18, preferably based on UV, in order to avoid the addition of bactericidal disinfectants, ensures the germ-free nature of the wash water. A buffer tank 19 filled with air, in conjunction with the pump 15, ensures an even flow of water into the downstream washing rack. A pressure measuring device 39 is used to monitor and control the pressure.

An outlet 38 alternatively leads into the sewage system and serves to drain off excess water in times of above-average water accumulation. This is particularly expedient if the treatment plant also treats surface water from a gas station area and is exposed to large amounts of water due to heavy rainfall. Otherwise the system works in 100 cycle operation.

Further pressure measurement points are located in line 27 to the bioreactor and 30 to the clean water tank and bear the reference number 40. They serve to monitor the working pressure of the pumps 9 and 10.

In the event that there is extensive contamination with dirt particles or biomass in one of these containers, a backwashing process is initiated from the pure water tank 11 via lines 37, pump 15 and lines 16 and 17 into the suspended matter filter 7 and the bioreactor 8. The water enters the reactors via the lower spider 26 and rinses the dirt particles or biomass via the overflow 28 and the line 14 into the sludge trap 2. In this way, microorganisms also get into the Sludge trap 2 and can colonize it and cause biological treatment of the sedimented dirt.

At times of low washing activity, i.e. H. especially at night, on weekends and on public holidays, a water circuit is preferably kept in operation in order to keep the suspended matter filter and the bioreactor in operation. This cycle begins in the pure water tank 11 and runs via the line 37, the pump 15 and the line 43 back into the storage basin 3. The gastric valve 44 is activated via the central control device. At the same time, the check valves 41 and 42 to the washing system and in the backwash lines are blocked. The cycle then runs, as in normal treatment operation, from the storage basin 3 via the suspended matter filter 7 and the bioreactor 8 into the pure water tank. In the case of a prolonged circulation, the quality of the water in the circuit and the switched-on containers gradually approaches the quality of the water in the pure water tank 11.

3 shows a particular embodiment of the bioreactor 8 according to the invention with regard to its overflow 28. In the case of backwashing, the backwashing water is led from a pure water tank via line 30 into the lower collecting space 46. From the collecting space 46, it enters the fixed bed 48 through the sieve gauze 47, rinses it and flushes residues and non-firmly adhering microorganisms into the upper space 49. The backwashing water runs out via the overflow 28, which is bowl-shaped - or funnel-shaped and opens into the drain line 14. The bowl-shaped or funnel-shaped design of the overflow 28 with an upwardly tapering cross section leads to an acceleration of the water flow on the way up, so that the torn particles accelerate and over the edge of the overflow 28 into the bowl and from there into the line 14 be performed. The backwashing flow therefore runs relatively evenly in the area of the fixed bed and directly above and only accelerates in the upper area so that the dirt particles can be conveyed specifically into the overflow. As can be seen from the illustration in FIG. 4, two reactor vessels 50 and 51 are required for the bioreactor 8 for a given treatment plant. The two containers 50 and 51 are identical in shape and content. Each of the containers corresponds to the module of a modular system, which by multiplying the modules corresponds to the on-site capacity of the processing plant. Since the plan of the reactor vessel 8 consists of the plan of the two modules 50 and 51, it corresponds to twice the plan of the two modules, the outline of which is formed by shorter sides of the rectangle 52, 53 and longer sides of the rectangle 54, 56. The length of the shorter sides of the rectangle 52, 53 corresponds in the exemplary embodiment to an on-site specification that results, for example, from a standardized door opening of 80 cm, through which the two modules would have to fit if they were installed in a room whose access is determined by the door opening . The further surface dimensions are predetermined by the rectangle sides 54, 56 of equal length, which, taking into account the container height H, results from the desired container volume. The container height is therefore usually also determined by the assembly and / or the room height. The multiplication of the containers 50 and 51 then results in the on-site predetermined capacity of the processing plant. While the container layout is specified by the dimension L specified by the customer, the rectangular container dimension 1 can be selected for the module.

In this way, each capacity of the processing plant can be managed with the modules 50 and 51.

The container has flat rising walls 57 to 60 and a flat bottom not shown in FIGS. 4 and 5. The rising walls 57 and 58, partially shown in FIG. 5, are made of thermoplastic material in the form of plates 61 and 61 of the same thickness. These plates are on each other associated edges at 63 with a weld seam arranged at 64 connected materially to one another. Together with the sufficiently dimensioned plate thickness, these material-tight connections result in a dimensionally stable container that is able to carry the loads to be absorbed almost without deformation. A so-called high-pressure polyethylene can be used as the thermoplastic.

For the cohesion of the two modules 50 and 51 and their correct assembly, a base frame 65 composed of metal profiles 65 is provided in a rigid manner. The frame members, some of which are shown at 66 to 68, can also be assembled in the corners to form a frame by means of material connections, in particular welds, in a rigid manner.

Claims

Expectations

1. Bioreactor for the treatment of water contaminated with organic substances, in particular from car washes, in which the reactor vessel has a fixed bed which consists of a porous support material which is adsorptive and porous for the organic constituents of the waste water and which is known per se, the organic constituents of the water degrading microorganisms is populated, characterized in that the fixed bed (48) is on a permeable support (47), a water collection space (46) is provided below the fixed bed, which is upstream of the outlet (26) for the treated water, the Drain (26) is also designed as a backwash inlet, and an inlet (24) and a backwash outlet (28) are provided above the fixed bed (48).

2. Bioreactor according to claim 1, characterized in that the permeable support (47) consists of sieve gauze.

3. Bioreactor according to claim 1 or 2, characterized by a return line (19) with the air injector (10) switched on for returning air saturated with pure water into the bioreactor (8).

4. Bioreactor according to one of the preceding claims, characterized in that the inlet (24) and / or the outlet (26) are designed as a distributor spider.

5. Bioreactor according to one of the preceding claims, characterized by dry-running protection in the bioreactor (8).

2 nights

6 .. bioreactor according to claim 5, characterized by a level control via control lines (S) with switching points for the minimum and maximum water level depending on the respective operating state.

7. Bioreactor according to one of the preceding claims, characterized in that the backwashing outlet (28) is designed as an overflow arranged centrally in the bioreactor (8), which tapers towards the top.

8. Bioreactor according to one of the preceding claims, characterized in that the porous carrier material is in bulk.

9. Bioreactor according to claim 8, characterized in that the porous carrier material consists of coal, clay, silica gel or zeolites in pellrtized form or of foam plastic curls.

10. Bioreactor according to one of the preceding claims, characterized in that the porous carrier material consists of activated carbon or expanded clay with a grain size of 1 to 10 mm, a density of 0.40 to 1.0 cm ³ / g and a surface area> 500 m ² .

11. Bioreactor according to one of the preceding claims, characterized by pressure measuring devices (40) which are connected downstream of the bioreactor (8).

12. Bioreactor according to one or more of the preceding claims, characterized by a plan of the reactor vessel (8), which is predetermined by the customer in a surface dimension (52, 53) and its further surface dimensions (54, 56) of its plan, taking into account the container height (H ) are adapted to a container volume that corresponds to the module (50, 51) of a modular system, which by Multiplication of the containers (50, 51) corresponds to a capacity of the processing plant that is predetermined by the customer.

13. Bioreactor according to one or more of the preceding claims, characterized in that the plan of the container is rectangular to square, the area dimension (2) provided by the customer being determined by the length of one of the two parallel side pairs (52, 53; 54, 56).

14. Bioreactor according to one or more of the preceding claims, characterized in that the container has flat rising walls (57 to 60) and a flat bottom, which consist of a thermoplastic material and at their mutually associated edges (63), for example, materially connected are welded.

15. Bioreactor according to one or more of the preceding claims, characterized in that a high-pressure polyethylene (HDPE) is used as the thermoplastic.

16. Bioreactor according to one or more of the preceding claims, characterized in that a common base frame is provided for holding together several containers of the modular system.

17. Bioreactor according to one or more of the preceding claims, characterized in that the area dimension predetermined by the customer is the width of a door opening of 80 cm, which forms the access to a installation room of the processing plant.