DE3607520A1 - Process and device for anaerobic waste water purification - Google Patents

Abstract

The invention relates to a process and a device for anaerobic waste water purification. It can be employed in the biological purification, with the aid of anaerobic microorganisms, of waste water (effluent) containing organic impurities. The aim of the invention is a considerable increase of the purification capacity of anaerobically functioning small-scale sewage treatment plants with the tank volume remaining the same. The increase of the purification capacity is to be achieved without additional energy consumption. The technical object of the invention is the increase of the biomass available for the anaerobic degradation of the organic impurities contained in the waste water. The object is achieved by introducing according to the invention support material, for colonisation by anaerobic microorganisms, into the digestion space. The biomass available for the degradation of the organic impurities is increased, taking into consideration the concentration-dependence of the reaction velocity of biological processes, in such a way that the same degradation capacity is always achieved in the entire digestion space through which the flow passes. The device according to the invention, in which woven material is preferably used for additional colonisation surfaces for anaerobic microorganisms in the digestion space, is characterised in that the additional growth surfaces for the biomass are built into the digestion chamber alternately at two different depths.

Description

Disposal and facility for anaerobic wastewater treatment

The solution according to the invention can be used in biological cleaning of waste water containing organic pollutants with the help of anaerobic microorganisms in small wastewater treatment plants.

The state of the art in the field of biological wastewater treatment already includes various processes for aerobic and anaerobic wastewater treatment, where microorganisms settle on a carrier material in the reaction space as well as devices for the implementation of such processes.

The carrier material is used, on the one hand, to wash out to prevent the microorganisms with the treated wastewater and on the other hand to to establish the best possible contact between the wastewater to be treated and the biomass.

Aerobic fixed bed reactors, so-called trickling filters, are already known where chunks of very coarse grain are used, this coarse grain is necessary to avoid clogging, although this is often expensive Measures for an even wastewater distribution are required.

In DE-AS 2550818 an aerobic description is used for biogical Full purification of the wastewater described, in which the AB water together with compressed air pressed through adhesive bodies (sponge or foam bodies) to back up the biomass wind. Since the adhesive bodies in the ventilation containers after a certain amount of time clog strongly with Biemasse, their degradation capacity is due to insufficient oxygen supply return.

The Biemanse as a whole needs more oxygen than can penetrate through the slowed diffusion into the deeper layers of the biomass.

DE ~ OS 24 18 586 describes a device and a method for the aerobic biological purification of wastewater, in the case of the vertically hanging, as Dividing walls formed webs of fabric divide the ponds like a channel, so that artificial Flow paths arise. On these partitions it will be in the richer ones Layered areas of the water surface work more or less effectively Forming organic turf. Since the fabric webs are completely below the Finding the water surface is the oxygen supply to the formation of the biological Lawn is not always sufficient, especially since the supply from special air-water emitters takes place below the surface of the water and the oxygen supply is only indirect takes place over the flowing water.

An anaerobic wastewater treatment process is known in which in the reactor as a carrier material for anaerobic micro-organisms macroporous substances can be arranged with a low specific weight. With the carrier material a fluidized bed or a fixed bed is formed, with the wastewater from bottom to top is passed through the reactor at the appropriate speed. For the reactor, which is preferably operated as a tube reactor, is an additional energy expenditure necessary.

AT-PS 363 871 describes a sewage treatment plant for biological purification of wastewater described, consisting of a circular building with a primary clarifier, a with a buoyant fixed-bed reactor, an aeration tank and a secondary clarifier, the fixed bed reactor consisting of lumpy material should serve as an adhesive surface for anaerobic microorganisms. as material of the fixed bed reactor is at least partially lighter than water. There is preferably bloating Aflwendun £ '. The material floats on or in the wastewater to be cleaned. The reactor, which is connected upstream of the aeration tank, is in a known manner from the bottom to flowed through above.

Furthermore, a sewage treatment plant is in the further development of that in the AT-PS 363 871 known solution, which consists of a primary clarifier and one with a buoyant fixed bed reactor provided with an anaerobic cleaning occurs, exists. Downstream of this second basin is a third basin, in den, an aerobic cleaning of the wastewater takes place. The third Beclcen, which with is equipped with a fixed bed reactor, the material of which is lighter than water, will flowed through from top to bottom.

In the case of the latter two solutions for sewage treatment plants for biological Wastewater treatment does not result in a positive enonorgy balance with additional material expenditure aims.

In the case of the known technical solutions with in or in the wastewater floating support material, there is a risk that especially with low laminar Flow of the wastewater to be treated through the reactor increases the biomass so abundantly the carrier material eddeiht that it comes to a blockage of the reactor.

According to AT-363 871 for drawing off the waste water according to the invention in The perforated tube lying in the shimmering fixed bed reactor would be functionally impaired.

The aim of the invention is to substantially increase the Cleaning performance of anaerobic small sewage treatment plants with constant Basin volume or based on the same connection values of such a system the solution according to the invention an economical construction with reduced container dimensions enable.

@The cleaning performance should be improved without additional expenditure of energy can be achieved.

The technical object of the invention is to increase the for the anuerobic degradation of the organic impurities contained in the wastewater Available biomass.

With the solution according to the invention, the practical residence time of the Wastewater in the reactor is extended and the hydraulic area of action is enlarged will.

The invention is not intended to be very effective only in new construction anaerobic small sewage treatment plants can be used, but synonymous, starting of the small sewage systems that have already been built many times, one adapted to their construction enable rational reconstruction in order to increase their performance.

The object is achieved by bringing the invention according to the invention Carrier material for colonization with anaerobic microorganisms in the digester.

The introduction of carrier material per se is considered to be known.

According to the invention, when installing the additional vegetation areas for the microorganisms, the concentration dependence of the reaction rate, biological processes are taken into account.

For the degradation of the same BOD concentrations are progressing Response time requires a disproportionately greater amount of time.

According to the invention, the biomass available for degradation is related on the roughness through which it flows - corresponding to an exponential function like this increases that the same extraction rate is always achieved in the entire septic tank.

As the reaction time progresses - starting from a given Faulraux Volume - a progressively increased amount of biomass made available.

The significantly increased cleaning performance is the same Digestion volume reached.

The contact between the vegetation and the wastewater to be cleaned is designed particularly intensely and at the same time the laminar tone of the Wastewater significantly favors, indeni according to the invention: ß a vertically running meandering flow direction of the wastewater is forced.

The direction of flow of the sewage is directed so that each one of the Flows under vegetation areas and flows over the following in the direction of flow. This creates intensive contact between the wastewater to be cleaned and the Biomass settled in vegetation areas both on the front and on the Backside built-in vegetation area guaranteed.

The inventive design of the wastewater flow path is at the same time a substantially longer practical residence time of the wastewater in the Lazy room achieved. This means. there is no need to flow through an enlarged septic tank, to achieve an increased cleaning performance.

The extension of the practical residence time in the digester, which always the increase in cleaning performance is justified with the same digester volume achieved.

The device according to the invention for performing the method exists zLulI one made of all-round stabilized, rigidly built-in vegetation areas and for others from predominantly stabilized, partially flexible vegetation areas for anaerobic microorganisms made of reticulated, closely-meshed tissue material, which proves to be highly resistant to the aggressiveness of the sewage.

The vegetation areas are alternating at two different heights one behind the other, following the direction of flow of the wastewater, installed in the digester.

They are provided with a corresponding stabilization structure, which from one in its width dimensions corresponding to the geometry of the reactor Frame with one or more Qaerver struts.

The stabilization structures of all vegetation areas are above the water level, preferably at the level of the upper edge of the partition between the primary clarifier and digester by means of a suitable structural solution in the anaerobic reaction space hooked.

In particular, there is a side overhang on the long sides of the frame of the vegetation fabric provided, which in a suitable manner zwseks good seal the septic tank wall is pressed against it. So that the wastewater is in the invention Defined flow direction is forced and other delayed flow paths are avoided.

In the case of the rigidly built-in vegetation areas, the fabric material is on all sides enclosed by the stabilization structure. Accordingly, the In these cases, the upper edge of the vegetation area is above the water level.

The length of the rigidly built-in vegetation area is stabilized on all sides dimensioned so that a favorable undercurrent allows. will. At the in The growth area following the flow direction is the growth tissue in the stabilization structure built in that the upper edge of the growth area Be deposited below the water level is, the lower edge of the stabilization structure is at a gorin'em distance from the reactor floor.

In this vegetation area, the vegetation tissue does not close with the The lower edge of the stabilization construction, but a flexible one follows Part that is dimensioned in its length so that it loosely overlaps on the reactor floor rests on which the pollutants are deposited during the anaerobic process, enclose the flexible part of the B-growth area and thus a good seal between the ground surface and the vegetation surface.

The wastewater is after entering the digester and contact with the first vegetation area, which is underflow, forced, to flow up between the first and second vegetation area, the second vegetation area to overflow, in order to then be forced back between two in a row built-in vegetation areas to flow down, there in contact with the on the Reactor bottom deposited biomass to come and a renewed upward flow to volführeine The lower end of every other vegetation area is kept flexible and preferably inclined in the direction of the sludge bottom opening for favorable regeneration to ensure the system The sludge removal from the digestion chamber into the pre-septic tank, which takes place through the generation of hydraulic overpressure in the digester, is due to the flexible, loosely overlapping, lower Not at the end of every second vegetation that is anchored in the settled mud hindered According to the object of the invention, the solution according to the invention not only the construction of powerful small wastewater treatment plants with a small reactor volume guaranteed, but the invention allows in a rational way, adaptable to the respective reactor geometry, the reconstruction of already built anaerobic working small sewage treatment plants with the aim of increasing their cleaning performance significantly increase0, The invention is explained in more detail below using an exemplary embodiment will.

Figures 1, 2 and j represent an anaorobic, cylindrical Small wastewater treatment plant.

The figures 4 and 5 show a cuboid small sewage treatment plant.

The wastewater to be cleaned flows continuously through the inlet 5 in the primary clarification chamber. 1, in which the coarse material 8 is deposited. Through the The flow openings 9 located in the partition 4 are used for the pre-clarified wastewater into the digestion chamber 2, which is responsible for the anaerobic degradation of organic impurities serves. The vegetation areas 1 2, 1 3 for the anaerobic microorganisms are in the digestion chamber 2 in such a way that the wastewater enters the digester 2 only in a vertical direction can traverse muzzle-shaped flow direction.

The vegetation areas 12 and 13 are with the help of the stabilization structure 10, 11 oingobaut in different heights in the digester.

The stabilization structures 10, 11 consist of one Frame with one or more transverse struts, are alternately at the same distance from each other at the same distance from each other by means of a suitable construction solution in the septic chamber and are in their width dimension according to the circular plan in each case the specific distance between partition 4 and the inside of the Adapted to the outer wall of the container. They are sealed against the reactor wall by suitable pressing of a sufficient side protrusion of the fabric of the vegetation areas 12, 13.

For the vegetation areas 12, 13 is preferably a permanent, close-meshed related material for application

bio e vegetation areas 12 are on all sides. the stabilization structure 10 washed and correspond in their wings about three quarters of the length of the partition 4th

The vegetation areas 13 are in such a way in the stabilization construction 11 installed so that its upper edge is below the water level. the The lower edge of the stabilization structure 11 is at a short distance from the floor of the reagent appropriate. The vegetation curses 13 do not end at the lower edge of the stabilization structure 11. It is followed by a flexible hole 14 that loosely overlaps in the direction of inclined of the sludge floor vent, rests on the reactor floor.

They settle on the roactor floor during the anaerobic cleaning process .The fine materials 15 and close the flexible because 14 of the vegetation areas 13 a.

After the wastewater to be cleaned in the course of crossing the septic chamber 2 the vegetation areas 12 below it flows and the vegetation areas 13 has flowed over, it passes through the flow openings 9 in the partition wall 5 into the Final clarifier 3, in which the drain 7 is located, through which the biological treated wastewater leaves the small sewage treatment plant.

It proves itself in the partition between the primary and secondary clarification chambers A pressure equalization opening with a non-return valve is available as an option, for static reasons 17 to be arranged.

This ensures that both chambers are filled evenly and prevents them the sludge return from the secondary clarification chamber to the primary clarification chamber.

Figures 4 and 5 show a cuboid small sewage treatment plant with the same structural elements as the cylindrical embodiment in FIGS. 1 to 3 The technological sequence of biological cleaning is analogous the one described for FIGS. 1 to 3.

In the digester 2 have a rectangular one in this case Ground plan of all vegetation areas 12, 13 for the anaerobic microorganisms the same Width measurement. The vegetation areas 12, 13 are provided with the appropriate stabilization structures 10, 11 installed in the digester 2 that the distances between two successive vegetation areas 12, 13 - based on the reaction space flowed through -continuously reduce.

List of the reference cells used 1 primary clarification chamber 2 digestion chamber 3 Final clarification chamber 4 Partition wall, the primary clarification chamber from the digestion chamber and the final clarification chamber separates 5 partition between digestion chamber and secondary clarification chamber 6 inlet 7 outlet 8 coarse matter 9 Flow openings 10 Stabilization construction for vegetation areas under flow 11 Stabilization construction for overflowing vegetation areas. 12 Underflowing vegetation areas 13 overflowing vegetation areas 14 more flexible Because of the vegetation area 15 fines 16 Pressure compensation opening 17 Pressure compensation opening with non-return valve

Claims (10)

P a t e n t a n s p r ü c h e 1. Process for anaerobic wastewater treatment, in which to increase the cleaning performance the contact area between to cleaning wastewater and biomass by introducing additional carrier material for the annaerobic microorganisms, the contact between growth areas and too roinigem em wastewater bosenders intonsiv gostaltot and at the same time the laminure Flow of wastewater is supported, characterized in that the for the Abbeu of the organic impurities available biomass -related to the flowed through Lazy room - increased according to an exponential foundation and a vertical one Forced flow direction of the wastewater to be cleaned through the lazy room will. 2. Facility for anaer wastewater treatment, preferably fabric material used for additional colonization areas for anaerobic microorganisms in the digester is, characterized in that the additional vegetation areas for the biomass are alternately built into the reaction chamber at two different heights. 3. Device according to claim 2, characterized in that alternately In the direction of flow of the wastewater, on the one hand, the upper edge of the vegetation area above of the water level and, on the other hand, the upper edge of the vegetation area below the Water level is arranged. 4. Device according to claim 3, characterized in that the visiting areas, whose upper edge is above the water level. from a stabilization structure at all times are enclosed, 5. Device according to claim 3, characterized in that the Visiting areas, the upper edge of which is below the water level, are not end at the lower edge of the stabilization structure, which is at a short distance is arranged above the reader floor, but rather a flexible toilet adjoins the vegetation area. 6. Device according to claim 5, characterized in that the flexible held part of the vegetation area, loosely overlapping, in the direction of the mud bottom opening rests inclined on the reactor floor. 7. interest device according to claim 4 and 5, characterized in that each vegetation area is attached to a stabilization structure. 8. Device according to claim 4 and 5, characterized in that Sufficient lateral overhang of the vegetation tissue over the stabilization structure is present, which for sealing in a suitable manner to the opposite Reactor walls is pressed. 9. Device according to claim 4, characterized in that the stabilizing structure at a sufficient distance for the underflow through the wastewater to be cleaned ends above the reactor floor. 10. Device according to claim 7, characterized in that each stabilizing structure in a suitable manner at the level of the upper edge of the partition between the primary clarification chamber and Digestion chamber is suspended in the reaction chamber.