WO2009065509A1 - Method and device for treating sludge - Google Patents

Abstract

According to the invention, in at least one first step the sludge is subjected in a disintegration device (3) to a disintegration process, wherein particles and/or aggregates contained in the sludge are at least partially disintegrated and in a second step the sludge is subsequently mixed in a flocculant feeding device (5) with flocculant.

Description

 METHOD AND DEVICE FOR TREATING MUD

description

The invention relates to a method and an apparatus for treating sludge.

Sludges from a variety of sources and processes, such as industrial process or mining sludges, or environmental or biogenic sludges to be disposed of or environmentally problematic, must undergo various treatments, particularly dewatering and / or disintegration.

Biogenic sludges are of animal or human origin and are a mixture of liquid phase or liquid, mostly water, and solid phase or solid particles comprising biogenic particles or organic solids and are like cells and microorganisms, especially bacteria, and aggregates thereof. In addition, organic or inorganic substances can also be dissolved in biogenic sludges and also a gas phase, for example in the form of gas bubbles or dissolved gas, the gas originating in particular from the, in particular aerobic or anaerobic, decomposition of organic substances in the sludge. Sewage sludge is a biogenic sludge that occurs in wastewater treatment.

Wastewater treatment plants are used to purify wastewater, which usually have a pre-treatment tank after mechanical pre-treatment, in which undissolved substances such as faecal matter and paper etc. settle or float on the surface. The corresponding pre-clarified waste water is now fed to a biological stage in which organic substances in the wastewater are removed by microorganisms and the supply of atmospheric oxygen and inorganic substances are partially oxidized. A common method for this biological step is an activated sludge process in one Aeration tank with a downstream secondary clarifier. In the activated sludge process, the biogenic constituents of the wastewater are continuously degraded by adding activated sludge containing masses of flocculated aggregated bacteria and by aerating in the aeration tank biotically oxidizing aebro. In the secondary clarifier, the activated sludge is separated by settling from the wastewater and a portion of the sludge is recycled as return sludge back to the aeration tank to keep the concentration of microorganisms in the activated sludge tank sufficiently high. The excess sludge produced by the increase in biomass in the secondary clarifier is thickened together with the primary sludge of the primary clarifier tank in a pre-thickener for further treatment and then pumped to an anaerobic digestion in a digestion tower. The digested sludge is then fed after passing through a Nacheindickers a sludge press for drainage and then disposed of. There are also known plants in which no primary sedimentation tank is present. Here then only the excess sludge from the secondary clarifier on the pre-thickener is then usually fed without digester the sludge press and then disposed of the dewatered sludge.

For dewatering or drying sewage or industrial sludge, a method is known in which the sludge through a filter system, in particular a chamber filter system, or a centrifuge (decanter) is performed, which squeezes out the substantially consisting of water liquid content of the sludge and the solid constituents thus filtering out of the mud.

The sludge is now before dewatering a flocculant (flocculant) containing polymers, added to increase the degree of dewatering or the degree of drying of the sludge, so to better drain the sludge. The mode of action of the flocculant can be thought of as the polymers binding the particulate matter in the sludge in flakes or flocculation and thereby assisting or improving their separation from the water. The filtered out dehydrated Block mass is also referred to as a filter cake. The polymers also improve the passage of water through the filter cake at the subsequent sludge levels.

DE 198 08 156 A1 discloses a device for treating conditioner for aqueous sludge with a rotating distributor head for mixing a mixture of active substance stock solution and make-up water in a mixing chamber and a seed device which mixes the active substance solution mixed in the mixing chamber as a conditioning agent at the flowing in a delivery pipe aqueous sludge emits. The distributor head has distributed about its axis of rotation substantially parallel to the axis of rotation extending longitudinal slots as fluid outlets for the mixture and radially outward, and along the axis of rotation extending mixing vanes. The mixture flows through a shaft of the distributor head and through the slit-shaped fluid outlets to the outside into the mixing chamber where it is mixed by the mixing blades. The speed of the distributor head is operated in a range between 700 rpm (revolutions per minute) and 2,500 rpm.

The effectiveness of the biological treatment stage in sewage treatment plants can be increased by using so-called homogenizers or disintegrators for treating the sewage sludge, in particular the return sludge, primary sludge or excess sludge and also the digested sludge. By means of these homogenizers or disintegrators, on the one hand, the size of the solid particles in the sludge is reduced and homogenized, thus providing a larger effective surface for the degradation, and on the other hand, enzymes (exoenzymes) and biogenic particles adhering to the cell walls of the cells are detached and dissolved reintroducing the fluid and releasing endoenzymes even by at least partially destroying the cell walls from the cells themselves. All these measures increase the efficiency of biodegradation by the microorganisms in the sludge, especially in the activated sludge of the biological degradation stage. DE 100 40 546 A 1 discloses a system for the mechanical disintegration of biogenic sewage sludge with a rapidly rotating tube-head structure having a head with radial openings and radial wings.

DE 100 40 545 A 1 also discloses a system for the mechanical disintegration of biogenic sewage sludge, in which the sewage sludge in a starting state comprises microorganisms in the form of cells and a solid, which is formed essentially by aggregates of the cells and suspended solids, and in which causes a disintegration process for the destruction of aggregates and destruction of cells, wherein in a first disintegration process primarily the destruction of aggregates is caused and in a subsequent, separate second Desinteg- rationsvorgang primarily the destruction of cells is caused. In the first disintegration process, the sewage sludge is preferably subjected to separation parts such as strip-shaped wings and possibly additionally with slot-like openings of a rotary wing device and the cells are destroyed only to a very limited extent, but released by the destruction of aggregates enzymes that destroy cells. In the second disintegration process, the sewage sludge is preferably treated with an ultrasonic homogenizer or by means of high-power pulses, and cells are destroyed directly and to a considerable extent by the cavitation generated thereby.

WO 2005/028375 A1 discloses a method for comminuting or dosing down particulate substances in suspensions of microorganisms in a carrier medium, in particular in waste waters or sludges of biological sewage treatment plants, in which the carrier medium carries with it a flow channel constructed in the manner of a load nozzle narrowing and then widening cross-section is pumped under pressure and thereby accelerated quickly and then delayed again, causing hydrodynamic cavitation in the Laval nozzle. The invention is based on the object of specifying a new method and a new device for treating sludge, in particular sludge, containing organic cells and aggregates of cells, in particular biogenic sludge such as sewage sludge.

This object is achieved according to the invention in terms of the method with the features of claim 1 and solved with respect to the device with the features of claim 16. Advantageous Ausges- and developments according to the invention will become apparent from the respective dependent claims.

The invention is based on the consideration, when withdrawing liquid or liquid phase, in particular water (dewatering), from sludges prior to the addition of flocculant to subject the slurry to an upstream disintegration step and thereby particles and / or aggregates contained in the sludge, in particular organic cells and aggregates From organic cells, at least partially disintegrate, so destroy, break up, unlock, dissolve and / or crush.

The disintegration, destruction or dissolution of the aggregates, in particular cell aggregates or cell aggregates, leads to a separation of the particles, in particular cells, or to a smaller average cell or cell aggregate size or aggregate or particle size and thus to a larger surface to which the flocculant can attach or wet it. The flocculant can now displace a larger amount of water or general liquid molecules of the particles or cells, which significantly increases the degree of drying of the sludge with the same added amount of flocculant per sludge amount unit.

In particular, the disintegration or destruction or rupture or disruption of the cells, especially their cell membranes, renders all cells and microorganisms such as bacteria, archaea and fungi or, in the case of plant cells, also the (additional) cell wall, accesses the cytoplasm or cell interior, which consists of water at a percentage of typically 80 to 95%. As a result of this disintegration of the cells, not only can the water partially escape from the interior of the cell and be separated from the solids phase of the sludge by the flocculant, but the flocculent can also contain the cell membrane and possibly the cell wall as well as inside or inside the cytoplasm Components of the cells that are to be assigned to the solid phase bind or accumulate on them and separate them from the water or the liquid.

It has been found that the upstream disintegration process with the ensuing aggregate and / or particle disruption, in particular cell aggregate and / or cell disruption, markedly increases the degree of dryness of the sludge subsequently added with the flocculant during a subsequent drying process.

In a preferred embodiment, cavitation is generated in the sludge upon disintegration. Cavitation is the creation of gas-filled cavities in a liquid when the static pressure falls below the vapor pressure of the liquid, which is typically several millibars. The local short-term vaporization of the liquid then forms gas bubbles which, when the static pressure exceeds the vapor pressure, implosion-like collapse virtually at the speed of sound. In the collapsed cavities, very high pressures of possibly thousands of bar are created. Cavitation thus arises when the flow velocity exceeds a corresponding value, so that the static pressure correspondingly falls below the vapor pressure. The cavitation leads to enormous inertial forces in the medium or sludge that cause disintegration.

For generating the cavitation in the sludge during disintegration, any method known per se can be used, for example the use of ultrasound or high-performance pulses or stirred ball mills, For example, as described in DE 100 40 545 Λ 1, or a hydrodynamic method as described for example in WO 2005/028375 A 1, where, as described there in each case a further disintegration upstream with a rotating rotor, so a two-stage disintegration can be provided.

In a particularly advantageous embodiment, at least one rotor is used for disintegrating the sludge prior to flocculant addition, which rotor is rotated about its axis of rotation in the sludge, in particular in a flow space in which the sludge flows. Preferably, cavitation is also generated with the rotor by rotating the rotor at a rotational speed in the slurry which is adjusted, controlled or regulated depending on the nature and flow of the slurry and the geometry of the rotor occurs in the mud on the rotor, in particular on each rotor blade, or, in other words, is above the cavitation limit. The speed of the rotor is also dependent on the pressure in the sewage sludge, ie the static pressure, as well as on the flow velocity of the sewage sludge and thus the dynamic pressure of the sewage sludge. The pressure and flow rate of the sewage sludge in turn depend on the delivery pressure of a conveyor, in particular a pump, for the sludge and on the geometry of the flow channel or space in which the sewage sludge flows and in which the rotor is arranged, as well as on the viscosity of the sludge , From certain flow velocities, correspondingly higher rotational speeds, of the rotor, a larger stationary cavity occurs on the rotor surface, in particular the rotor blades, that is to say a coherent gas layer which surrounds the rotor blades. This is called full cavitation in comparison to partial cavitation, in which individual gas bubbles form on the surface. Full cavitation is more advantageous than partial cavitation in terms of the somewhat more uniform surface loading. The rotational speed of the rotor required in each case for the occurrence of partial cavitation or full cavitation becomes empirical or metrological or even theoretical for the respectively given plant-specific parameters and parameters such as the geometry of the flow space and the rotor, the sludge properties, in particular viscosity, and the sludge pressure or delivery pressure determined and set in operation. The speeds required for cavitation can be very different depending also on the geometry of the rotor, in particular its diameter. In practice, rotors with speeds above 3,000 rpm, in particular between 3000 rpm and 7000 rpm, preferably between 5000 rpm and 6200 rpm, or even between 3,300 and 4,500 rpm, have proven themselves, however these values are not limiting.

In one embodiment, the or each rotor has at least one, in particular at least two, openings and / or slots and / or recesses and / or elevations or projections, which protrude in particular from the axis of rotation to the outside, on. The rotor preferably has demolition edges and / or cutting edges and / or shearing edges which, in particular, tear or shred or separate or separate solid particles and aggregates contained in the sludge, in particular aggregates of cells. In a particular embodiment, the rotor has at least one, in particular at least two, rotor blades. But it can also be provided tooth-like projections in the manner of a gear or a saw blade. In addition, edges may additionally or exclusively be formed at openings or slots in the rotor.

Furthermore, a plurality of rotors can be arranged side by side, in particular in a star shape or parallel to one another.

For mixing or introducing the flocculant into the at least partially disintegrated sludge, any known device or method can be used, for example according to DE 198 08 156 Λ 1. In particular, the flocculant is introduced or inoculated into the sludge via a rotating mixer or mixing head. Any flocculant suitable for the specific application and sludge may also be used as flocculant, with the flocculant usually being introduced in the form of a solution of active substance, in particular of an aqueous polymer solution, ie as a liquid flocculant.

In an advantageous combination of a disintegration rotor for disintegration and a mixing rotor or rotating mixing head for introducing the flocculant, a modular system is proposed which comprises a rotary drive, which from the outside to a wall of a room in which the sludge is located, in particular a flow space or a flow tube, can be fastened or attached and at the drive shaft either either the disintegration rotor or the mixing rotor can be coupled or fastened.

In this case, preferably when coupling the rotor, in particular disintegration rotor, a sliding seal, in particular mechanical seal, arranged for sealing in the mud or flow space for the sludge, so that the sludge cools the sliding seal. Preferably, a disintegration unit, which comprises the disintegration rotor and the sliding seal, attached as a unit to the wall and the disintegration rotor coupled to or to the drive shaft of the drive or arranged and releasably secured rotatably, in particular by means of clamping screws.

When coupling the mixing rotor, however, a feed system is coupled with at least one feed channel for the flocculant and arranged a sliding seal for sealing in the feed, so that the flocculant cools the mechanical seal. Preferably, a mixing unit which comprises the mixing rotor, the flocculant feeding system and the sliding seal is attached as a unit to the wall and the mixing rotor coupled or arranged on or to the drive shaft of the drive and releasably secured, in particular by means of clamping screws. The or each rotor is preferably coupled to a rotary shaft, in particular detachably connected, wherein the rotary shaft for securing against the force surges and load changes at two along the axis of rotation (B) spaced apart locations in two rotary bearings is rotatably or rotatably mounted.

In a further embodiment, a drive, which is preferably adjustable in its rotational speed, is provided for the rotor at least for the disintegration rotor.

The drive is preferably coupled to the rotor or the rotary shaft via a toothed belt, wherein the toothed belt is flexible and at least partially formed from a mechanically damping material, in particular a composite material made of a tensile material such as a tissue or fibers, in particular glass fibers, and at least one elastomeric material to achieve dissipation of movements within the toothed belt, such as vibrations and load surges, and / or damping decoupling of the drive from the rotor. It is expedient in this case to use an elastomer material, in particular for the teeth, and / or a round tooth profile for a better stress distribution and a higher overall load and / or wear-reducing coatings on the tooth side and / or the back side.

For tensioning or adjusting the tension of the toothed belt and / or for setting a distance between the disintegration unit or the Flockmittelzugabeeinrichtung an adjusting unit for the drive is preferably provided with which the drive is mounted in particular on a base plate.

The rotary shaft now has in one embodiment, in particular between the two pivot bearings, a gear in which engages the toothing of the toothed belt. The drive now preferably has a drive gear, which is directed around a preferably parallel to the axis of rotation of the rotor, Rotary axis is rotated or rotated and has an external toothing, in which the toothing of the toothed belt also engages. The transmission ratio of drive to rotary shaft or rotor is chosen in particular between 1: 1, 5 to 1: 5, preferably at about 1: 2.

The rotary shaft can now have a free end at an end facing away from the rotor. Furthermore, the rotary shaft, in particular at an end facing away from the rotor, can be connectable or connected to a feed device for feeding a substance, for example a gas or also a liquid, through a cavity of the rotary shaft to the rotor for introduction into the sludge, wherein in particular Gas is supplied, which reduces the cavitation limit and / or faster by a higher vapor pressure, the Kavitationsgasblasen or the gas film formed, so that the speed of the rotor can be reduced, for example nitrogen.

The invention will be explained below with reference to exemplary embodiments. Reference is also made to the drawings, in whose

1 shows a device for treating sludge with a disintegration unit and a flocculant addition unit in a perspective view,

2 shows the device according to FIG. 1 with tube units opened for the purpose of illustration, in a perspective view, FIG.

3 shows the rotor and the rotary shaft of the disintegration unit according to FIG. 1 and FIG. 2 and a lower half of the associated tube unit in a perspective individual view,

4 shows the rotor of the disintegration unit according to FIG. 3 in a side view, 5 shows the rotor according to FIG. 4 in a cross section,

6 shows a further embodiment of a disintegration unit in a partially sectioned side view,

7 shows the rotor of the disintegration unit according to FIG. 6 in a perspective view and FIG

FIG. 8 shows the rotor of the flocculant adding unit according to FIG. 1 and FIG. 2 and a lower half of the associated tube unit in a perspective individual view, in each case schematically. Corresponding parts and sizes are provided in the Figures 1 to 8 with the same reference numerals.

The device according to FIG. 1 is designed as a compact module with a base plate 16 which can be parked on a floor by means of feet and a frame 14 mounted on the base plate 16, on which a control unit 12 is mounted or arranged. On the bottom plate 16, a support plate 18 is arranged and fixed, on which in turn a disintegration unit 3, a drive 9 for the disintegration unit 3 and a flocculant addition unit 5 with an associated drive 25 are mounted and fastened.

The disintegration unit 3 is associated with a first pipe unit 17, which is designed as a T-shaped pipe connection piece. The first pipe unit 17 has in the flow direction of the sludge S arranged one behind the other initially on a first port 17A as inflow or inlet of the sludge S for connection to an unillustrated transport pipe for the sludge S and then a second port 17B as an outlet or outflow of the sludge S. and between them on a pipe member extending perpendicular thereto, a third terminal 17C for connecting the entire pipe unit 17 to a support plate 37 fixed to the support plate 18. A second, likewise T-shaped pipe unit 15 is assigned to the flocculant addition unit 5 and likewise has a first connection 15A and a second connection 15B arranged one behind the other in the direction of flow of the sludge and a third connection 15C for connection to a piece of pipe perpendicularly projecting therebetween the tube unit 15 to the drive 25 of the flocculant addition unit. 5

The ports 17B of the first pipe unit 17 and 15A of the second pipe unit 15 are connected to each other, so that the two pipe units 17 and 15 are connected in series in the direction of flow of the sludge or are successively flowed through by the sludge. The second port 15B of the second pipe unit 15 is also connected to a transport pipe, not shown, for the removal of the sludge.

The two tube units 15 and 17 are of identical design in the illustrated embodiment. The connections of the tube units 15 and 17 preferably have connecting flanges, as shown, which are connected to one another by means of screw connections. The transport tubes, not shown, preferably also have connection flanges for connection to the connections 17A or 15B.

As can be seen in FIG 2, in which the tube units 15 and 17 of FIG 1 are shown open, in the first tube unit 17, a rotor 7 of the disintegration unit 3 and in the second tube unit 15, a rotor 8 of the Flockmittelzugabeeinheit 5 are arranged.

The rotor 7 of the disintegration unit 3 rotates in operation about a rotation axis B, wherein the axis of rotation B of the rotor 7 is directed in particular perpendicular to the flow direction of the sludge S in the first tube unit 17. The disintegration unit 3 further comprises a rotary shaft 30 coupled to the rotor 7 and extending along the axis of rotation B. The rotary shaft 30 is rotatably or rotationally supported at two locations spaced apart along the axis of rotation B in two pivot bearings 31 and 33. The two pivot bearings 31 and 32 are mounted on the support plate 18. The rotary shaft 30 is guided by the support plate 37.

A gear 33 of the disintegration unit 3 is connected to or with the rotary shaft 30 and rotates synchronously with the rotary shaft 30 about the rotation axis B, and is particularly arranged between the two rotary bearings 31 and 32, in the example of FIG 1 closer to the pivot bearing 31.

The drive 9 comprises at least one electric drive motor 91, not shown, which drives a drive gear 90 on the front side of the drive motor 91 via a motor shaft, which rotates about a rotation axis A, and preferably also a power converter, in particular frequency converter, for variable-speed control of the drive motor 91 The drive gear 90 has an external toothing 93 into which an internal toothing 19 of a toothed belt 11 engages.

The toothed belt 1 1 rotates on the one hand the drive gear 90 and on the other side the gear 33 of the disintegration unit 3. The gear ratio between the drive gear 90 and the gear 33 of the disintegration unit 3 is selected so that the drive gear 90 rotates slower than the gear 33, typically in a ratio of 1: 1, 5 to 1: 5, preferably 1: 2.

For tensioning the toothed belt 1 1 and / or adjusting the distance between the drive 9 and disintegration unit 3, an adjusting unit 92 is mounted on the bottom plate 16, via which the drive 9 relative to the bottom plate 16 and thus to the disintegration unit 3 adjustable, in particular in its distance from the disintegration unit 3 in different positions, preferably continuously, is adjustable. The toothed belt 1 1 consists of a flexible material, in particular at least partially made of a hard elastic material, which also preferably good damping properties, ie a good dissipation of movements or absorption of kinetic energy, within the toothed belt 1 1, for example, vibrations and load surges, has. Preferably, the toothed belt 11 consists of a, preferably provided with a fabric or fibers as a tensile material, elastomeric material such as a rubber or natural rubber material or a synthetic rubber.

The rotor 7 connected to the rotary shaft 30 rotates at the same rotational speed as the rotary shaft 30, also driven by the drive 9 via the toothed belt 1 1. Since the drive 9 is a controllable or controllable drive in its rotational speed, the rotor 7 is also in its speed control or adjustable.

The rotational speed of the rotary shaft 30 and its gear 31 and thus of the rotor 7 of the disintegration unit 3 is set or controlled or regulated via the rotational speed of the drive 9 so that it lies above the cavitation boundary, so that cavitation occurs in the sludge S on the rotor 7 , In the case of the rotor 7 in the illustrated embodiment, the rotational speed or rotational frequency of the rotor 7 is selected above 3,000 rpm (revolutions per minute) or 50 Hz, in particular between 3,000 rpm. (50 Hz) and 7000 rpm. (116.7 Hz). For a number of investigated types of sludge, a number of revolutions between 5500 and 6200 rpm, in particular of about 6000 rpm. (100 Hz), proved to be advantageous. The rotation speed or angular frequency is the speed or rotation frequency multiplied by 2 π.

Due to the high rotational speed of the rotor 7 of the disintegration unit 3, a strong cavitation in the sludge S, which causes or supports the desired disintegration effect, on the other hand, however, leads to hard knocks and knocking noises, which in turn into the rotary shaft 30 be fed back. Due to the flexible, partially elastic and damping toothed belt 11, these disturbing mechanical feedbacks such as shocks, vibrations (vibrations) and the like are largely decoupled from the drive 9. The timing belt 11 allows safe and slip-free operation even at the here required quite high numbers of revolutions.

The pivot bearings 31 and 32 are formed so that they on the one hand and the considerable mechanical load changes and dynamic tilting moments from the rotor 7 on the one hand during the rapid rotation of the rotary shaft 30

Rotary shaft 30 act, yet cause a stable storage. For example, rolling bearings can be used which are used in stone crushing mills or non-contact magnetic bearings.

As can be seen in FIGS. 1 and 2 and in detail in FIGS. 3 to 5, the rotor 7 comprises a central rotor body 71, which is designed as a hollow shaft closed at the front end, at which two mutually offset by 180 ° or in the opposite direction radially to the rotational axis B outwardly projecting rotor blades (or: rotor blades) 70 are arranged. On the rotor blades 70 extensions or connecting elements 78 are provided for connection of the rotor 7 with an outer sleeve of the sliding seal 72 by means of a screw connection, not shown. The entire rotor 7 is preferably formed symmetrically to a symmetry plane contained the rotation axis D, d. H. the rotor blades 70 are mirror-symmetrical to each other. As a result, in particular the axis of rotation A is a self-axis or main axis of inertia of the rotor 7 and imbalances are kept small or avoided.

The rotor blades 70 of the rotor 7, in the embodiment shown in FIGS. 3 to 5, have end faces 7OA on the end viewed in the direction of the rotation axis B and radially outer faces 70B and in the direction of rotation D surfaces 7OC pointing towards the rotor 7 and in the opposite direction to the direction of rotation D. surface 7OD. All mentioned surfaces 7OA to 7OD of the rotor blades 70 are formed in the illustrated embodiment as flat surfaces or flat sides, that is flat. The surfaces 7OC and 7OD directed in the direction of rotation D or in opposite directions to the direction of rotation D are parallel to one another and run essentially parallel to a plane containing the axis of rotation B. Perpendicular to the two surfaces 70C and 70D extends the outer surface 7OB and is thus perpendicular to a radial direction to the axis of rotation B. Also, the outer surfaces 7OB of the rotor blades 70 are flat and form with the surfaces 7OC and 7OD each have a straight edge parallel to the axis of rotation B runs. The outer surfaces 7OB have an approximately uniform rotational speed since they are approximately at the same radius. The end faces 7OA of the two rotor blades 70 are, however, arranged obliquely for optimum fitting in the cross section of the flow space 6, ie at an angle to the radial direction, and planar and thus form with the surfaces 7OC and 7OD respectively a rectilinear edge and with the outer surface 7OB also a perpendicular to these two edges extending another straight edge. Instead of end faces 7OA running obliquely away from the end, however, end faces 7OA which extend away from the axis of rotation A in the radial direction and which are directed perpendicular to the outer faces 7OB could also be provided, so that a cuboid rotor blade 70 results.

The surfaces 7OC and 7OD are formed wider than the end surfaces 7OA and the outer surfaces 7OB forming narrow sides of the rotor blades 70. The dimensions are indicated in FIGS. 4 and 5, namely the radial dimensions or widths of the rotor blades 70 with d, the length of the rotor blades 70 measured parallel to the rotation axis B with the connecting elements 78 with L and the width of the rotor blades 70 measured perpendicular to the length 1 b.

The inner diameter of the rotor 7, which corresponds to the diameter of the rotor body 71 without the rotor blades 70, is denoted by di and is in particular between 11 mm and 82 mm, the outer diameter of the rotor. sector 7 together with the rotor blades 70 and thus the outer distance of the outer surfaces 7OB of the rotor blade 70 is denoted by da and is in particular between 14 mm and 120 mm, preferably between 35 mm and 92 mm, preferably between 75 mm and 85 mm.

Preferred values for the dimensions of the rotor blades 70 are between 76 mm and 124 mm for the length L, between 4 mm and 18 mm for the width b and between 3 mm and 53 mm for the radial width d.

The length L of the rotor blades 70 is adapted to the flow cross-section of the sludge S or diameter of the pipe section of the pipe unit 17 and is in particular between 28% and 95% of the diameter of the sludge pipe of the pipe unit 17.

Between the two rotor blades 70, in the exemplary embodiment according to FIGS. 3 to 5, slots 75 are additionally provided in the wall of the rotor body 71 offset by 90 ° relative to the rotor blades 70, through which the sludge S can partially pass into the interior of the rotor body 71 and thereby the disintegration effect can be further increased. The length of the slots 75 measured parallel to the axis of rotation B is denoted by 1 and the width of the slots in a rear area with dl and in a front area with d2, wherein the rear width dl of the slots 75 is preferably smaller than the front width d2. Preferred values of the dimensions of the slots 75 are between 2 mm and 6 mm for the rear width d 1, between 4 mm and 8 mm for the front width d 2 and between 60 and 90 mm for the length 1

The rotary shaft 30 protrudes, as seen in Figures 1 to 3, with an end 35 beyond the pivot bearing 32 addition, said end may be free or may be connected to a device not shown, by means of which, if the rotary shaft 30 as Hollow shaft is formed by the hollow shaft, a material, such as a gas or a liquid, can be guided to the rotor 7 of the disintegration unit 3 and via the slots 75 in the sludge S can be introduced. For this purpose, for example, a gas can be supplied which reduces the cavitation limit, which therefore causes the cavitation gas bubbles or the gas film to form faster, for example because of its higher vapor pressure, so that the rotational speed or rotational speed of the rotor 7 of the disintegration unit 3 can be reduced. For example, a gas such as nitrogen can be supplied here.

FIGS. 6 and 7 show an alternative embodiment with a closed rotor 7, which passes through an opening in the tube wall 60 of FIG

Sludge pipe 6 projects into the flow space for the sludge S, without requiring a T-piece as in Figures 1 to 3. In contrast to Figures 1 to 5, the rotor 7 according to Figures 6 and 7, no slots 75, but only the rotor blades 70 on the rotor body 71, which can then be solid or not hollow inside. In addition, a direct drive is provided as drive 9, which drives the rotor 7 directly about the common axis of rotation B.

In the embodiments shown, the rotor 7 and its mechanical seal 72 are arranged completely in the flow space for the sludge S formed inside the pipe unit 17 or the pipe 6. This arrangement of the mechanical seal 72 in the sludge S has the advantage that the mechanical seal 72 can be cooled by the sludge S. The mechanical seal 72 seals the passage of the rotary shaft 30 through the connection 17C and the flange as well as the carrier plate 37 or the tube wall 60.

The rotor 8 of the flocculant addition unit 5 is driven directly by a separate drive motor 25, thus rotating at the same rotational speed as the drive motor 25 about the common axis of rotation C. However, an intermediate transmission with a corresponding transmission ratio may also be provided. Furthermore, the rotor 8 of the flocculant addition unit 5 can also be connected via a further toothed belt or belt another transmission means are driven by the drive motor 91 of the drive 9 for the disintegration unit 3 or by its own drive motor or drive. Preferably, one of two, in particular identical units, each with a drive (9), a toothed belt (1 1) and one, in particular hollow inside, rotating shaft (30) with pivot bearings (31, 32) and rotor (7, 8) can be used both for the disintegration unit 3 and for the flocculant addition unit 5, so that a single drive module with rotor can be used for both applications. The speeds can then be set correspondingly different and in the case of the disintegration unit 3, the hollow shaft (30) sealed and in the case of Flockmittelzugabeeinheit 5 can be supplied via the hollow shaft (30), the flocculant F.

The rotor 8 of the flocculant addition unit 5 is in particular constructed essentially identical to the rotor 7 of the disintegration unit 3 according to FIGS. 4 and 5 and has an internally hollow rotor body 81 with rotor blades 80 and slots 85 arranged therebetween, through which the latter passes via the interior of the rotor Hollow shaft or the rotor body 81 supplied flocculant F during rapid rotation in the mud S 'emerges. A mechanical seal of the rotor 8 is designated 82.

During operation of the device, the sludge S to be treated first flows through the tube unit 17 and is subjected to disintegration therein by the rotor 7 of the disintegration unit 3 located in the tube unit 17. The edges of the rotor blades 70 and, if slots 75 are present, also their edges form during the rapid rotation of the rotor 7 tear or shear edges plowing through the mud and particulate matter contained in particular tearing or crushing aggregates of cells or cells themselves or split. The cavitation in the sludge arising at the rotor blades 70 due to the speed of the rotor 7 selected above the cavitation limit considerably increases the disintegration effect. The surfaces 7OC of the rotor blades 70, which are aligned in the direction of rotation D tet also form baffles that have a reducing or homogenizing effect on the sludge composition.

In a biogenic sludge or sludge containing organic cells and aggregates thereof, the disintegration of aggregates of organic cells and the organic cells themselves are digested and crushed.

Due to the previous disintegration, the water is already partially removed from the sludge particles and aggregates of cells and cells themselves, and owing to the larger surface areas achieved, more flocculant can accumulate on the surface of the sludge particles in the flock additive addition unit 5. Depending on the sludge used, the average particle size or size of the solid particles formed in the sludge, in particular from the cells, can be reduced by a factor of ten.

The integrated or digested sludge after the disintegration unit 3 is denoted by S 'and is supplied to the flocculant addition unit 5. Through the rotor 8 of the flocculant addition unit 5 is continuously in the sludge S ', which has passed through the disintegration unit 3 and flows through the pipe section 15, flocculant F mixed, in particular a per se known flocculant based on polymer.

The disintegrated sludge S 'leaves the tube unit 15 at connection 15B together with the added fluid F as mixture S' + F and is now fed to a dewatering unit, for example a filter press or centrifuge, not shown here, and dried there or dehydrated. The high-efficiency flocculant, in particular based on polymer, improves the degree of drying or the drainage of the sludge. The system according to the invention finds favored use in a sewage treatment plant, in particular in connection with a biological stage, preferably an activated sludge system.

However, the application of the system according to the invention is not limited to this particular application, but can be used in all biogenic sludges or industrial sludges, in particular for their drainage.

LIST OF REFERENCE NUMBERS

3 disintegration unit

5 flocculant addition unit

6 mud tube

7 rotor

8 rotor

9 drive

11 timing belt

12 control unit

14 frames

15 pipe unit

15A to 15C connection

16 base plate

17 pipe unit

17A to 17C connection

18 carrier plate

19 toothing

27, 28 Flange

30 rotary shaft

31 pivot bearings

32 pivot bearings

33 shaft gear

35 end

36, 38 shaft section

37 carrier plate

60 pipe wall

70 rotary wings

7OA to D area

71 rotor body

72 sliding seal

75 slot 78 fasteners

80 rotary wings

81 rotor body

82 sliding seal

85 slot

88 fasteners

90 drive gear

91 drive motor

93 external toothing

A, B, C axis of rotation

D turning direction b width di, since diameter dl, d2 width d radial width

F flocculant

1, L length

S, S 'mud

Claims

claims 1. A method for treating sludge, in which a) in at least a first process step, the sludge is subjected to a disintegration process in which particles and / or aggregates contained in the sludge are at least partially disintegrated, b) subsequently in a second process step the sludge with flocculant is offset. 2. The method of claim 1, wherein the sludge contains organic cells and aggregates of organic cells, in particular a biogenic sludge such as sewage sludge, wherein the aggregates contained in the sludge of cells and the cells themselves are at least partially disintegrated. 3. The method of claim 2, wherein in the or by the disintegration of the cells, in particular the cell membranes and optionally the cell walls, cell fluid from the cytoplasm or cell interior, especially cell water, is released. 4. The method of claim 2 or claim 3, wherein the flocculant cell membranes and possibly cell walls as well as contained in the cell interior or cytoplasm, the solid phase attributable components of disintegrated cells binds or attaches to and separates them from the water or liquid and / or in which the flocculant attaches to the surfaces of cells and of cell components of disintegrated cell aggregates and / or cells. A process according to any one of the preceding claims, wherein the flocculant added to the slurry promotes or enhances the separation of the liquid phase or liquid, especially water, from solids, including solid portions of the cells, of the slurry. 6. The method according to any one of the preceding claims, in which from solid particles and / or solid cell constituents of the sludge and flocculants flake formations of different sizes are formed and liquid, especially water, of the sludge is released. 7. The method according to any one of the preceding claims, wherein the disintegration process comprises at least two disintegration steps, wherein in a first disintegration step primarily the Disintegration of aggregates of cells is caused, in particular by means of a rotor rotating in the sludge, and in a subsequent, second disintegration step primarily the disintegration of cells is effected. 8. The method according to any one of the preceding claims, wherein in the disintegration process cavitation is generated in the sludge. 9. The method of claim 8, wherein the cavitation in the sludge by means of ultrasound or high-performance or high-pressure pulses or hydrodynamically, in particular by means of at least one cavitation nozzle is generated. 10. The method according to any one of the preceding claims, wherein in the at least one first method step at least one Ro in the sludge is rotated to perform a disintegration process. 1 1. The method of claim 10, wherein the rotor has at least one, in particular at least two rotor blades. 12. The method of claim 10 or claim 11, wherein the rotor has at least one, in particular at least two, openings and / or slots and / or recesses and / or protrusions and / or projections and / or demolition and / or cutting and / or Shearing edges, in particular on the rotor blades, which in particular tear in the sludge contained solid particles or aggregates, in particular aggregates of cells and / or cells or crush or separate. 13. The method according to any one of claims 10 to 12 and claim 8, wherein the cavitation is generated in the sludge by means of the rotating rotor in the sludge by the rotor with a set above the cavitation limit speed or at a speed which depends on the nature and flow the sludge and the geometry of the rotor is adjusted, controlled or regulated so that cavitation occurs in the sludge on the rotor, wherein in particular a gas is supplied which reduces the cavitation limit and / or by a higher vapor pressure faster Cavitation gas bubbles or the gas film is formed, so that the speed of the rotor can be reduced, for example nitrogen. 14. The method according to any one of claims 10 to 12 and claim 8 or claim 13, wherein the rotational speed of the rotor (7) for the disintegration process is set above 3,000 rpm, in particular between 3000 U / min and 7000 U / min, preferably between 5000 U / min and 6200 U / min 15. The method according to any one of the preceding claims, in which the flocked sludge is subjected to a mechanical drying operation in a third process step, in particular a filter press, for example a chamber filter press, or a centrifuge is supplied. 16. An apparatus for treating sludge, in particular biogenic sludge such as sewage sludge, with a) at least one disintegrating device (3) for disintegrating the sludge (S), b) at least one flocculating agent addition device arranged downstream of the sludge in the direction of flow of the sludge (5) to add flocculant (F) into the sludge. 17. The apparatus of claim 16 with a Flockmittelzugabeeinrichtung downstream in the flow direction of the sludge drying device, in particular filter press or centrifuge, for drying the sludge. 18. Device according to claim 16 or claim 17, in which at least one disintegration device has at least one rotor rotating or rotatable in the sludge. 19. The apparatus of claim 18, wherein the rotor has at least one, in particular at least two rotor blades. 20. Device according to claim 18 or claim 19, in which the rotor of the disintegration device has at least one, in particular at least two openings and / or slots and / or openings. has recesses and / or elevations or projections and / or tear and / or cutting and / or shear edges, in particular on the rotor blades, which tear particularly contained in the sludge solid particles or aggregates, in particular aggregates of cells and / or cells or crush or split. 21. Device according to claim 19 or claim 20, wherein the rotor (7) of the disintegration device has at least one, preferably at least two openings or slots for the passage of Sludge, in particular between the rotor blades (70). 22. Device according to one of claims 16 to 21, wherein the Flockmittelzugabeeinrichtung has at least one rotating or rotatable in the sludge rotor. 23. The apparatus of claim 22, wherein the rotor (8) of the flock agent addition means comprises at least one, in particular at least two rotor blades. 24. The apparatus of claim 22 or claim 23, wherein the rotor (8) of the Flockmittelzugabeeinrichtung at least one, preferably at least two openings or slots for the escape of flocculant in the mud and / or passage of sludge, in particular between the rotor blades (70 ). 25. The apparatus of claim 19 or one of the dependent claims 19 or claim 23 or one of the claim 23 dependent claims, wherein the rotor blades (70) of the rotor (7) on the in the direction of the axis of rotation (B) of the rotor (7) end faces (70A) and radially outward outer surfaces (70B) and in the direction of rotation (D) of Ro- Sectors (70C) and opposite to the direction of rotation (D) directed surfaces (70D), wherein preferably at least a portion of these surfaces (7OA to 70D) of the rotor blades (70) are flat or flat and / or the Au - Sense surfaces (70 B) preferably to each other at the same radius to Rotary axis (B) are. 26. Device according to claim 25, wherein the surfaces (7OC and 70D) of the rotor blades which are directed in the direction of rotation (D) or opposite to the direction of rotation (D) are directed parallel to one another and / or substantially parallel to a rotation axis (B ) and / or extend perpendicular to the outer surface (70B) and / or perpendicular to a radial direction to the axis of rotation (B) and / or with the outer surface (70B) each form a ne particular straight edge, preferably parallel to the axis of rotation (B) runs. 27. The apparatus of claim 25 or claim 26, wherein the end face (70A) of each blade (70) is inclined, d. H. is arranged at an angle to the radial direction, and / or forms in each case a particularly straight edge with the surfaces (7OC, 70D) pointing in or opposite to the direction of rotation and with the outer surface (70B). 28. Device according to one of claims 25 to 27, wherein in or opposite to the direction of rotation facing surfaces (7 OC, 70 D) are formed wider than the end face (70 A) and / or the outer surface (70 B). 29. Device according to claim 19 or one of the claims dependent on claim 19 or claim 23 or one of claims dependent on claim 23, in which the rotor or the rotor blades gel (70) has a length (L) between 76 mm and 124 mm and / or a width (b) between 4 mm and 18 mm and / or a radial dimension (d) between 3 mm and 53 mm and / or the length (L) the rotor blade (70) or the rotor (7) is adapted to the flow cross-section of the flow space for the sludge (S) and / or in particular between 28% and 95% of the diameter of the flow space. 30. The apparatus of claim 19 or one of the dependent claim 19 claims or claim 23 or one of Claim 23 dependent claims, wherein an inner diameter (di) of the rotor (7) without rotor blades (70) is between 11 mm and 82 mm and / or an outer diameter (da) of the rotor (7) with the rotor blades (70) between 14 mm and 120 mm, in particular between 35 mm and 92 mm, preferably between 75 mm and 85 mm. 31. The device according to claim 19 or one of the claims 19 dependent claims or claim 23 or one of the claim 23 dependent claims, wherein the rotor (7, 8) offset two by 180 ° to each other or in the opposite direction radially to the axis of rotation ( B, C) outwardly projecting rotor blades (70, 80). 32. The apparatus of claim 19 or one of the dependent claims 19 or claim 23 or one of the claim 23 dependent claims, wherein the rotor (7, 8) has a central rotor body (71) on which in particular arranged the rotor blades are, wherein the rotor body is preferably formed inside hollow or as closed at the front side hollow shaft. 33. Device according to claim 19 or one of the claims dependent on claim 19 or claim 23 or one of claims dependent on claim 23, wherein the rotor blades (70) extensions or connecting elements (78) for connection düng with a sleeve of a sliding seal (72, 82) are provided. 34. Apparatus according to claim 18 or one of the claims dependent on claim 18 or claims 22 or one of the claim 22 dependent claims, wherein the rotor (7, 8) symmetrically symmetrical to a plane of symmetry formed and / or wherein the axis of rotation of the rotor is a self-axis or principal axis of inertia of the rotor. 35. The apparatus of claim 21 or one of the dependent claim 21 claims or claim 24 or one of Claim 24 dependent claims, wherein the length (1) of the openings or slots (75) is parallel to the axis of rotation between 60 and 90 mm and / or in which the width of the openings or slots (75) between 2 mm and 8 mm or in a front area (d2) is larger in a rear area (dl). 36. Device according to claim 18 or one of claims dependent on claim 18 or claim 22 or one of claims dependent on claim 22 with at least one drive, preferably adjustable in its rotational speed, for the rotor (7, 8) , 37. The apparatus of claim 18 or one of the dependent claim 18 claims or claim 22 or one of the claim 22 dependent claims, wherein the rotor (7, 8) coupled to a rotary shaft (30), in particular releasably connected, is. 38. Apparatus according to claim 36 or claim 37, wherein the drive (9) with the rotor (7) or the rotary shaft (30) via a toothed belt (1 1) is coupled, wherein the toothed belt (1 1) is flexible and at least is formed in part of a mechanically damping material, in particular a composite material made of a tensile material such as a woven or fibers and at least one elastomeric material, to a dissipation of movements within the toothed belt (11), such as vibrations and load surges, and / or a damping decoupling of An - To reach drive (9) from the rotor (7). 39. Apparatus according to claim 37 or claim 38, wherein the rotary shaft (30) at two along the axis of rotation (B) spaced apart locations in two pivot bearings (31, 33) is rotatably or rotatably mounted. 40. The apparatus of claim 38 when dependent on claim 38 and 37, wherein the rotary shaft (30), in particular between the two Drehla- g ^ren in appended to claim 37 or claim 39 (31, 32) a gear (33), in that the toothing (19) of the toothed belt (1 1) engages. 41. Device according to claim 38 or one of the claims dependent on claim 38 and according to claim 36, in which the drive (9) has a drive gear (90) which is mounted around a preferably parallel to the axis of rotation (B) of the rotor (7). directed, rotation axis (A) is rotated or rotatable and has an external toothing (93) into which the toothing (19) of the toothed belt (1 1) engages. 42. The device according to claim 36 or a claim dependent on claim 36, wherein the ratio of the rotational speed of the drive (9) to the rotational speed of the rotor (7, 8) between 1: 1, 5 to 1: 5, preferably at about 1: 2, is selected. 43. The apparatus of claim 41 and 40, wherein the transmission ratio between the drive gear (90) and the gear (33) of the rotary shaft (30) is selected so that the drive gear (90) rotates slower than the gear (33), in particular between 1: 1.5 to 1: 5, preferably about 1: 2. 44. Apparatus according to claim 37 or claim relating back to claim 37, wherein the rotary shaft (30) has a free end at an end (35) facing away from the rotor (7). 45. Apparatus according to claim 37 or claim relating back to claim 37, wherein the rotary shaft (30), in particular at one of the rotor (7) facing away from the end (35), with a feed device for supplying a substance, for example a gas or a Liquid, through a cavity of the rotary shaft (30) to the rotor (7) for introduction into the sludge (S) is connectable or connected. An apparatus according to any one of the preceding claims, wherein the disintegration means generates cavitation in the sludge. 47. Apparatus according to claim 46, wherein the disintegration device generates cavitation in the sludge by means of ultrasound or high-performance or high-pressure pulses or hydrodynamically, in particular by means of at least one cavitation nozzle. 48. The device according to claim 18 or one of the dependent claims on claim 18, wherein the disintegration device Cavitation in the sludge is generated by means of the rotor rotating in the sludge by setting the rotor at a speed set above the cavitation limit or at a speed that is adjusted, controlled or regulated depending on the nature and flow of the sludge and on the geometry of the rotor that Cavitation occurs in the sludge on the rotor, is rotated or in which the speed of the rotor of at least one disintegration device above the cavitation limit is adjustable, controllable or regulated. 49. Apparatus according to claim 48, in which the rotational speed of the rotor (7) of the disintegration device is set or adjustable above 3,000 rpm, in particular between 3,000 rpm and 7,000 rpm, preferably between 5,000 rpm and 6,200 rpm. min 50. Apparatus according to claim 48 or 49 when appended to claim 45, wherein the supply means supplies a gas which reduces the cavitation limit and / or causes the cavitation gas bubbles or gas film to form faster by a higher vapor pressure, so that the number of revolutions of the rotor (7) can be reduced, for example nitrogen. 51. Apparatus according to claim 36 and claim 37 or to a claim based on the two claims 36 and 37, in which the two pivot bearings are mounted on a common carrier plate (18) on which also the at least one or each drive (9, 25 ) for the or each rotor (7, 8) is attached. 52. The apparatus of claim 18 or one of the dependent claim 18 claims or claim 22 or one of Claim 22 dependent claims, wherein the rotor (7, 8) and / or the rotary shaft (30) has a sliding seal (72) which within the sludge or a flow space, in particular a pipe, is arranged for the sludge S. 53. Device according to one of claims 16 to 52, in which the disintegration device (3) is associated with a first tube unit (17) as flow space for the sludge and the flocculant-adding device (5) with a second tube unit (15) as flow space for associated with the sludge, wherein the two pipe units are connected to each other and are arranged one behind the other in the flow direction of the sludge and are constructed in particular identical. 54. The apparatus of claim 53, wherein at least one of the tube units is T-shaped and a piece of pipe, arranged in the flow direction of the sludge in succession, a first terminal (15A, 17A) and a second terminal (15B, 17B) and a middle pipe section having a third port (15C, 17C), wherein preferably the rotor and / or the rotary shaft is inserted or run into or through the middle pipe section via the third port and preferably the rotor in the pipe section between the first port and the second connection protrudes.