DE3214357A1 - System for recovering heat from sanitary and industrial waste water - Google Patents

Abstract

The invention relates to a system for recovering heat from sanitary and industrial waste water, having an accumulator (4), which can be connected via an accumulator inlet line (3) to a waste water channel and in which heat exchange surfaces connected to a heat pump (18) are arranged. The accumulator inlet line (3) is thereby surrounded in the accumulator (4) by heat exchange surfaces constructed with double walls and in the form of a plurality of concentric circles, the waste water being guided in the accumulator along the individual heat exchange surfaces (5) from the inside outwards and alternately from above to below. The medium to be heated is thereby in a counterflow, the individual heat exchange surfaces being provided with cleaning devices. <IMAGE>

Description

32H357

Patent Attorneys - 5

Dipl.-Ing. E. Eder
Dipl.-ing. K. Schieschke
8000 Munich 40, Elisabethstr. 34

Energiecontrol GmbH & Co. KG Kempfenhausen

Plant for the recovery of heat from sanitary and industrial wastewater

The invention relates to a plant for recovery of heat from sanitary and industrial wastewater, with one that can be connected to a sewer via a storage inlet pipe Storage tank in which heat exchanger surfaces connected to a heat pump are arranged.

Such a system is already known as the sand of technology, in which only warm wastewater is fed to the storage tank is (DE-OS 24 38 622). Inside the memory there is a heat exchanger, which is connected to a liquid medium with a Heating system is connected. The structural features of this known system are such that only an inadequate Use of the energy of the warm wastewater is given. Furthermore, this is known without special, constructive training System not suitable for the use of sewage contaminated with faeces.

The state of the art also includes an apparatus for heat recovery from wastewater, in which a downpipe, which is arranged in the storage tank, feeds wastewater from a helical one extending pipe train is surrounded, which is the heat transfer tube forms (DE-GM 76 13 872). Also this well-known

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location is not for the use of faecal wastewater suitable, in addition, in turn, the efficiency of this known device due to its structural peculiarities is to be regarded as insufficient.

The state of the art also includes heat exchangers with heat pumps for the recovery of thermal energy from waste water, (DE-OS 30 06 119, DE-GM 79 14 292, DE-GM 80 16 769). Also these well-known However, due to their special design features, systems have a low level of efficiency and, moreover, are not suitable for the use of sewage contaminated with faeces.

In contrast, it is the object of the present invention, based on the prior art mentioned at the outset, to provide a system to sctafrfen, which with a high degree of efficiency also in is able to manage faecal wastewater in terms of thermal energy to use.

This object is achieved in that in the memory the double-walled heat exchanger surfaces in the form of several concentric rings surround the storage inlet pipe, the wastewater in the storage tank along the individual heat exchanger surfaces from the inside to the outside and alternately from the top to the top is performed below that a to be heated in the heat exchanger surfaces Medium can be moved in countercurrent to the wastewater in the memory and that the heat exchanger surfaces are provided with cleaning devices are. This has the advantage that this invention The system is also suitable for the use of heat from sanitary, faecal-contaminated and industrial wastewater, with a high degree of efficiency. As a result of the cleaning device, there is always an optimal heat transfer between the two Media, namely the wastewater and the medium to be heated, achieved.

In a further embodiment of the invention, the end of the storage supply line protrude far into the memory and under it

32U357

When the water level is full. This is advantageous achieves that the inflowing liquid flows in without great turbulence and thereby that in the wastewater Contained heavy matter can sink better to the storage floor.

In a further embodiment of the invention, the heat exchanger surfaces alternately from the inside to the outside in the upper and lower area have waste water passages, whereby an optimal Use of the waste water heat is achieved. Furthermore, according to another feature of the invention, between the innermost heat exchanger ring surface and the Speieher inlet line just below the storage water level a perforated plate can be arranged, whereby advantageously floating coarse dirt is not can get between the heat exchanger ring surfaces.

In a further embodiment of the invention, the arched can Storage base have a storage drainage line that can be closed by a sensor-controlled valve. In a different configuration the invention there is the possibility that in the lower area of the memory one with an evacuation line connected, time-controlled sewage pump is arranged. Both options ensure in a simple manner that the storage tank can be emptied at the point in time when no more warm liquid is being supplied. According to another feature the invention, it is possible that the sewage pump are assigned nozzles, whereby advantageously the deposited Heavy solids are flushed into the suction points of the pump, so that a good and effective emptying of the memory is given. Here, the nozzles can be ring-shaped around the sewage pump be arranged around.

According to another feature of the invention, the medium to be heated can be guided in a serpentine manner through the heat exchanger surfaces be, with baffles open at the top and at the bottom alternately being arranged within the heat exchanger surfaces. This creates a very good guidance of the medium to be heated in the countercurrent principle

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and serpentine with respect to the wastewater.

The cleaning device of the present invention can, according to another feature of the invention, between the heat exchanger surfaces have perpendicularly arranged, planet-like brush rollers revolving around the central axis of the accumulator, the Brush rollers advantageously each on driven brush roller axles are arranged. These revolving brush rollers are advantageously always optimal when necessary the outer surfaces of the heat exchanger surfaces cleaned.

Here, the upper ends of the brush roller axles can be arranged on a support that runs around the central axis of the store be, wherein a toothed rail ring is arranged in the memory, on which the carrier rotates via driven gears. This The carrier is thus able to clean the perfectly with a full rotation around the central axis of the memory Perform heat exchanger surfaces. Here, the carrier has an inner guide in the area of the storage line and at least Two guide rollers in the outer area, so that a perfect guidance and storage of the rotating support is guaranteed is.

In a further embodiment of the invention, the brush roller axles can each rotate around their own axis, so that results in a planetary motion. Here, each brush roller axis has at least one on a stationary toothed rail ring running gear, in addition, the brush rollers are limited vertically movable. This will be advantageous undesired formation of grooves on the heat exchanger surfaces avoided.

According to another feature of the invention, the spacing between the concentric rings of the heat exchanger surfaces is from the inside to the inside different on the outside, the brush rollers being designed to be interchangeable. The heat exchanger surfaces are advantageous

liable to make better use of the brush rollers so set in their gaps that the wear and tear in Brush rollers reduced in diameter can be used in the next smaller, dimensioned intermediate space. The gearwheels can be driven via a switchable electric motor arranged on the carrier.

The invention is described in more detail below with reference to an embodiment shown in the drawing. In the Drawing show:

Fig. 1 is a schematic side view of the plant

for the recovery of heat with a heat pump;

Fig. 2 is a schematic side view of the memory

in section, showing the inflow of warm wastewater;

3 shows a side view of the memory, partly broken, with structural details;

4 shows a further side view of the memory,

partly broken, showing the movement of the medium to be heated;

FIG. 5 is a view X from FIG. 4; FIG.

6 shows a side view of the memory with the cleaning device inserted;

FIG. 7 shows a plan view of the cleaning device according to FIG. 6.

The system shown schematically in Fig. 1 for recovering heat from sanitary and industrial waste water consists in essentially from a memory 4, which is located in the inflow area of a sewer 40. Inside the memory 4 are

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the heat exchanger surfaces 5 through which medium 28 to be heated flows according to FIG. 1. These heat exchanger surfaces 5 are connected to a bottom pump 9. The heat pump 18, which is fed by the heat exchanger surfaces 5, exists from an evaporator with heat exchanger 17, a compressor 41, a diesel engine 42 and a heat exchanger 43. Furthermore is a buffer 44 and a utility water storage 45 provided.

The memory 4 located in the area of the sewer 40 is via a storage supply line 13 to the sewer 40 tied together. A heat sensor 1, which controls a diverting flap 2, is installed in the sewer 40. When warm liquid is under the set heat area in the sewage line 40 flows away, the diverting flap 2 remains inoperative and the waste water liquid is discharged into the sewer system. If liquids accumulate above the set heat range the diverting flap 2 comes into operation and blocks the discharge line 40 to the sewer system or the downpipe. Now the warm one flows Liquid via the storage supply line 3 into the storage unit 4. In this storage unit 4, the stored wastewater is heated withdrawn. If warm wastewater continues to flow in when the tank or storage tank 4 is full, the same amount of heat is extracted the reservoir 4 is discharged into the sewer system via an overflow channel 6, as shown by the direction of the arrow in FIG. 1.

The memory 4 is also provided with a memory drain line 27 provided in order to discharge the cooled liquid in this way from the memory 4 into the sewer system.

In Fig. 2, the memory 4 is shown in more detail. The memory consists of a cylindrical container with a curved shape Tank bottom 11. The storage inlet pipe 3, through which the warm liquid, i.e. the wastewater flows in. This storage supply line is so deep into the center of the container of the standing, cylindrical storage

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chers 4 introduced that its end is well below the water level of the memory 4 is in the filled state. This allows the flowing liquid to enter and without great turbulence As a result, the heavy solids contained in the wastewater can sink better to the container bottom 11.

In the insulated, double-walled memory 4 are a number of Heat exchanger surfaces 5 installed in a ring and surround the storage inlet line concentrically. The heat exchanger surfaces 5 are double-walled and in this case arranged in the memory 4 that the innermost ring in the process water state from Wastewater is flooded. The heat exchanger ring behind it protrudes over the process water condition, with in the lower area Water passages 25 are provided in the form of elongated recesses. The water flows over the in the upper area Sewage passages 24 and in the lower area via the sewage passages 25 serpentine from the inside to the outside. the The number of heat exchanger rings 5 is determined by the area required for the passage of heat. the After passing through the last heat exchange ring, liquid passed through in this way reaches the outer wall of the container and is over the Overflow channel 6, which runs around the reservoir 4, is fed back into the sewerage system through a collecting pipe 7.

Just below the storage water level there is one in storage 4 between storage supply line 3 and the innermost heat exchanger ring Perforated plate 8 installed so that floating coarse dirt cannot get between the heat exchanger ring surfaces 5.

A liquid energy transport medium is used in the double-walled heat exchanger surfaces 5 including the double-walled outer storage wall pumped in and thus extracted heat from the stored wastewater 29. The circulation takes place through the one shown in FIG Pump 9, which is attached outside of the memory 4.

If warm wastewater continues to flow in when the storage tank 4 is full, the same amount is transferred after heat is extracted from the storage tank 4 the overflow channel 6 is discharged into the sewer system.

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As soon as the contents of the memory 4 have cooled down, when no more warm waste water liquid 29 is supplied, what is determined by the sensor 10 according to FIG. 1 in the lower region of the memory 4, the memory 4 can be emptied.

There is once the possibility of doing this via the storage drain line to connect the memory 4 to the sewer system. For this purpose, a bottom valve 26 is opened via the sensor 10, whereby a return of the cooled wastewater liquid into the sewer system is possible. By the outflow of the liquid the heavy materials that have deposited in the vaulted container bottom are returned to the sewer system washed in. After the reservoir 4 has been emptied, the bottom valve 26 closes again, controlled by the sensor 10, whereupon the memory 4 is ready to receive new, warm liquid wastewater quantities.

If a gravity evacuation in the sense described above does not is possible, a time-controlled sewage pump 12 can be used, as shown in more detail in FIGS. This sewage pump 12 empties the memory 4 via an evacuation line 13 in the times when the slightest attack of warmth Sewage liquid is pending. In order to improve the flushing of the deposited heavy materials in the lower part of the reservoir 4, is 2 and 3, an annular nozzle tube 14 is present, its Nozzles are aligned in such a way that they flush the deposited heavy matter to the suction pumps of the sewage pump 12.

In Fig. 4 and 5, the energy transport medium guidance in the heat exchanger surfaces 5 is shown in more detail. Here it flows Medium 28 to be heated via inlet 16 into the outermost heat exchanger surface 5 and comes in a serpentine shape to the area of the inn-first heat exchanger surfaces and from there to the Outlet opening 30. The energy transport medium is routed in the heat exchanger surfaces 5 in a serpentine manner vertically by corresponding guide plates 15, as shown in FIG. 5 is shown in more detail. Pipes can also be provided.

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The medium 28 to be heated occurs at point 16 in each case the storage tank, in which the most strongly cooled wastewater liquid is located, and then flows in countercurrent the waste water liquid to the middle of the memory 4 and thus to the warmest point of the waste water liquid in the memory 4. From there, the medium 28 to be heated is fed to the heat exchanger 17 of the heat pump 18 according to FIG. 1. This heat pump 18 is controlled in its output by the respective heat accumulation in order to achieve maximum operating results.

To also fecal and industrially polluted warm sewage to be able to use the system according to the invention, the system according to FIGS. 6 and 7 has a revolving cleaning device on. This cleaning device consists of vertically arranged brush rollers 22 which are mounted on brush roller axles 20 are stored. These brush roller axles 20 are attached to a carrier 31, which in the interior of the store 4 over 360 running around. In this case, the carrier 31 has a guide 34 which is arranged in the area of the storage supply line 3.

In the outer area, the carrier has guide rollers 35 according to FIG. 7, which roll on the inner wall of the store 4. Furthermore, at least two gears 32 and 32 ″ are provided, which roll on a stationary ring gear 32 and are driven by an electric motor 23 according to FIG. 6. The brush roller axles are each provided with gear wheels 19, these gears 19 according to FIG. 6 with fixed toothed rails 21 work together. By rotating the carrier 31 as a result of the drive via the electric motor 23 and to the Toothed rails 21 running off gears 32 and 32 'move the brush roller axes 20 and thus the brush rollers 22 planet-like around the center of the store 4 and thereby effect optimal cleaning of the heat exchanger surfaces on both sides 5. The brush rollers 22 can also be moved slightly vertically in order to create grooves on the outer sides of the To avoid heat exchanger surfaces 15.

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The individual heat exchanger surfaces 5, i.e. the rings, are in their interstices for better utilization of the brush rollers 22 stipulates that the brush rollers 22, reduced in diameter due to wear, are dimensioned in the next smaller one Space between two heat exchanger surfaces can be used.

The brush 22, which rotates in opposite directions in a ring and also around its own axis, is advantageously used within the Storage 4 achieved a swirling effect of the warm wastewater, whereby the already pending, cooled liquid at the heat exchanger 5 again with other, warm wastewater is mixed. This ensures that the cooling of the waste water liquid standing between the heat exchange rings 5 occurs evenly, so that an optimal heat transfer between the two media is achieved. The drive of the brush rollers 22 takes place via the electric motor 23, which is designed so that the brush rollers 22 each after a circular movement by approx. 370 ° around the storage inlet line 3 in opposite directions Circular movement is switched.

There is also the possibility, not shown, of arranging all the brush rollers in a rotating basket, which is to Cleaning or repair purposes from the memory 4 as a complete Unit is designed to be removable.

Furthermore, the axes 20 of the brush rollers 22 can be passed through the lower rack 21 and each with one Propeller are provided, which always keep the openings 25 free of solids due to the turbulence effect will.

The system according to the invention results in an optimal one Utilization of any kind of warm waste water that arises.

Patent attorneys Dipl.-Ing. E. Eder Dipl.-Ing. K. Schieschke

Z "T. Munich 40, Ellsabethstr. 34

Claims (20)

32H357 Patent attorneys Dip! .- ing. E. Eder D:; - ¹ .- {ng. κ. Schieschke * - J. ".. üncii2; i 40, Elisabefhstr. 34 Energiecontrok GmbH & Co. KG Kempfenhausen Plant for the recovery of heat from sanitary and industrial sewage Patent claims: Plant for the recovery of heat from sanitary and industrial Wastewater, with one via a storage inlet pipe with a sewer connectable memory, in which with a heat pump connected heat exchanger surfaces are arranged, characterized in that the double-walled heat exchanger surfaces in the memory (4) (5) in the form of several concentric rings surround the storage supply line (3), with the wastewater in the storage (4) along the individual heat exchanger surfaces (5) from the inside outwards and alternately from top to bottom is that a to be heated in the heat exchanger surfaces (5) Medium can be moved in countercurrent to the wastewater in the memory (4) and that the heat exchanger surfaces (5) are provided with cleaning devices (19, 20, 21, 22, 23) are provided. 2. Plant according to claim 1, characterized in that the end of the storage supply line (3) far into the storage (4) protrudes and meanwhile the water level is in the filled state. 3. Plant according to claim 1, characterized in that the heat exchanger surfaces (5) alternately from the inside to the outside have waste water passages (24, 25) in the upper and lower area. 4. Plant according to claim 1, characterized in that between the innermost heat exchanger ring surface (5) and the Storage tank inlet line (3) just below the storage tank water level a perforated plate (8) is arranged. 5. Plant according to claim 1, characterized in that the arched storage base (11) through a having a sensor-controlled valve (26) closable storage discharge line (27). 6. Plant according to claim 1, characterized in that in the lower region of the memory (4) a time-controlled sewage pump (12) connected to an evacuation line (13) is arranged. 7. Plant according to claim 6, characterized in that the sewage pump (12) are assigned nozzles (14). 8. Plant according to claim 7, characterized in that the nozzles (14) are arranged in a ring around the sewage pump (12) are. 9. Plant according to claim 1, characterized in that the The medium to be heated is routed in a serpentine fashion through the heat exchanger surfaces (5). - 3 .1 :? : J ^: fO.: \. 32H357 10. Plant according to claim 9, characterized in that within the heat exchanger surfaces (5) are arranged alternately at the top and at the bottom, open baffles (15). 11. Plant according to claim 1, characterized in that the cleaning device between the heat exchanger surfaces (5) has perpendicularly arranged, planet-like brush rollers (22) rotating around the central axis of the store (4). 12. Plant according to claim 11, characterized in that the Brush rollers (22) are each arranged on driven brush roller axles (20). 13. Anlagejnach claim 12, characterized in that the upper ends of the brush roller axles (20) on a around the Center axis of the memory (4) circumferential carrier (31) are arranged. 14. Plant according to claim 13, characterized in that im Storage (4) a toothed rail ring (21) is arranged on which the carrier via driven gear wheels (32, 32 ') (31) revolves. 15. Plant according to claim 13 and 14, characterized in that the carrier (31) has an inner guide (34) in the area of the storage inlet line (3) and at least two guide rollers (35) has in the outer area. 16. Plant according to claim 11 to 15, characterized in that the brush roller axles (20) each rotate around their own axis. 17. Plant according to claim 16, characterized in that each Brush roller axis (20) has at least one toothed wheel (19) running on a stationary toothed rail ring (21). V ··! ·! I = ····; "V 32Η357 18. Plant according to claim 11 to 17, characterized in that the brush rollers (22) can be moved vertically to a limited extent. 19. Plant according to claim 1 and 11, characterized in that the distances between the concentric rings of the heat exchanger surfaces (5) are different from the inside to the outside and that the brush roller axles (22) are designed to be exchangeable. 20. Plant according to claim 14, characterized in that the gears (32, 32 ') via a on the carrier (31) arranged, switchable electric motor (23) can be driven. Patent attorneys Dipl .-! Ng. E. Eder D '; "l.-ing. K. Schieschke Cv ;;; ' ¹ f. ·: "? ■ : .-: i 40, F-Ifcubethstr. 34