DE10030784B4 - Device for dewatering solids separated from fluids - Google Patents

Abstract

Facility for dewatering of solids separated from fluids, in particular of Screenings, comprising a pressing device with at least one Working worm (10), which at least partially from a housing (11) surrounded, the housing (11) following the working screw (10) in the conveying direction at least one opening (12), characterized in that the screw turns the working screw (10) are arranged on a core (16), wherein the diameter of the core (16) of the working screw (10) is in conveying direction increased.

Description

The The invention relates to a device for dewatering solids which are separated from fluids, in particular screenings, comprising a Pressing device with at least one working screw, at least partly from a housing surrounded, the housing comprises at least one opening in the conveying direction following the working screw. The drainage or Dehumidification takes place after removal or separation of the solids out of the fluid instead.

Appropriate Pressing devices such as Rechengutwaschpresse are available in the stores. Such Rechengutwaschprints drain screenings, which was fair from wastewater. Corresponding contaminants Removing it from the wastewater is necessary to ensure safe operation to ensure the subsequent purification stages of the wastewater. The sewage sludge utilization and demand ever more sophisticated purification processes of wastewater a finer coarse separation of the waste water down to the millimeter range into it. Because of this and also due to the increase in corresponding impurities in the wastewater it is necessary to process the screenings in such a way that a recovery possible is. Here are basically three ways to disposal. These are the thermal recovery, the composting and the Disposal. At the thermal utilization it is necessary that the water content of the screenings is as low as possible Screenings otherwise can not be burned effectively.

Per Year and inhabitants fall in the Klärbetrieben of the Federal Republic Germany in dependence of the transmission widths of the computer systems, the type and length of the Drainage system and The respective season about 15 to 50 liters of screenings with a average water content of about 92% by mass. For example has at the sewage treatment plant Bülk the City Kiel the taken screenings an average dry matter content of 8% by mass. With the commercial Screenings washing press, the screenings on a dry matter content of 30% by mass (700 liters of water per ton) of dehydrated. The leftover So far, waste has been dumped in a landfill and disposed of in this way. Due to the relatively low dry matter content or the high Humidity of usually however, thermal treatment, if any, is very limited possible.

in the The prior art is various corresponding devices known.

The Document DE-U-299 18 072 discloses a device for discharging of purified solids from a rake processing device, when following a screw conveyor a discharge tube with an annular Compression is provided to squeeze out the residual fluid to effect in a restful computer. The auger has this one Screw coil on which a drive shaft with a constant diameter is arranged.

Out DE-U-91 09 180 a Rechengutpresse is known, which is a screw conveyor with a constant diameter shaft for transporting the screenings having a pre-press zone.

Farther DE-A-43 02 849 describes a device for removal of solids from a flowing Liquid. In this case, the device has a screw conveyor, the inlet side rotates freely in a pipe, with the conveyor spiral on a shaft is arranged, which has a constant diameter over the whole length having. A compression of the solids is achieved by a conical taper of the feed pipe in the area of the screw conveyor reached. For this purpose, the turns of the screw conveyor are in diameter adjusted accordingly.

Out DE-A-40 42 167 discloses a device for removing screenings a channel flowing liquid a sewage treatment plant described in which the conveyor spiral is arranged on a shaft with a constant diameter.

In The patent DE-C-39 42 561 is a screw conveyor described in which the helix of the screw conveyor a constant Increase. The device is in several pressing areas divided, wherein in each pressing area a helix on a shaft is arranged with a constant diameter.

The conveying helix is not continuously formed on the entire shaft of the screw, so that between two coils a cone body is arranged through the one to be drained Mud under pressure and compacted. About that In addition, the cone body acts at the transition from one pressing area to the next Pressing area in the sense of backflow formation, because the outside diameter of the Floor space of the cone body is larger as the diameter of the subsequent shaft.

The in DE-C-37 16 434 shown conveyor spiral a working screw has a shaft with a constant Diameter, around which the helix is arranged.

Furthermore, in WO-A-98/34731 a A method and a device for washing screenings that is considered to be generic to the present device for dewatering solids is described. The screw conveyor shown therein also has a shaft with a constant diameter.

in view of this prior art, it is an object of the present invention a device for dewatering of solids separated from fluids, in particular of Screening material, comprising a pressing device to indicate, by means of an increased Dehydration possible is. The device should also preferably be designed in this way be that this little has to be maintained.

Is solved This object is achieved by a device for dewatering solids which are separated from fluids, in particular screenings, comprising a pressing device with at least one working screw, the at least partially by a housing is to give, the casing comprises at least one opening following the working screw in the conveying direction, wherein the screw flights of the working screw are arranged on a core are, wherein the diameter of the core of the working screw in conveying direction increased.

So is it possible in a simple way the volume in the conveying direction shrinking in at least one section. By this measure is a Dehydration to at least 60 wt .-% dry matter content possible. The increase The dehydration is due in particular to the fact that during the drainage the material, ie the solids and in particular the screenings, is rotated by rotation of the working screw in and thus is also opened, whereby moisture nests are opened. This takes place at usual Rechengutwaschpresse not take place.

in the Under this invention is under solids in particular screenings from waste water, contaminants in sewage, sewage sludge, Cellulose (for example toilet paper and sanitary napkins), plastics, Sand and other coarse materials understood.

Preferably is at the beginning or before delivery the solids for the device according to the invention this cleaned by a car wash, in particular biological Shares are washed on the screenings or on the solids.

Of the Advantage of the device according to the invention is also due to that the movement of solids in the device is longer possible as with usual Pressing and that with increasing pressure the material is rotated, leaving less moisture nests. These will while the turn again and again unlocked, so in particular by the complex conveyor movement Dissipated water becomes.

By the inventive device is a 30 to 40% better drainage compared to usual dewatering presses possible. hereby fall significantly less transport costs and it is no more necessary, the remaining solids or dehydrated solids to spend on a landfill, since these are now dry enough, to be used thermally. It is with the dehydrated solids to reach a calorific value greater than the calorific value of Brown coal. The inventive device is a saving from up to about 50% disposal costs possible.

Preferably is a volume between the working screw or the working screw sections and the housing defined, wherein the volume in the conveying direction at least in a section down. By this preferred embodiment the invention is subject to the device less wear, since the advancement of the material material happen evenly can. The change of the Volume can be targeted to the respective processing Material adapted. Alternatively, it is preferably possible that Trains of the snail in the conveying direction tighter, so that in this way the pressure also increased evenly. Preferably reduces the volume defined by the screw flights and the housing is.

Preferably the volume reduction is continuous. By these preferably Design is the promotion The material flow even more uniform design.

If preferably a first drive is provided which drives the we least one working screw, wherein the first drive is infinitely adjustable, the speed of the working screw and thus the throughput of solids to the demand is readily adaptable. For example, a frequency converter from 0 - 100 Hz is used for this purpose. The higher the speed or the rotational speed of the working screw, the more pressure is built up in the front area. A corresponding control is indispensable, for example, during downpours in order to be able to cope with the accumulated amount of solids in the wastewater at all. During a downpour, it is possible to cope with up to 30 times the normal amount. This can be intercepted on the one hand by providing a further or larger reservoir and / or by increasing the throughput, which can be done by increasing the speed or the rotational speed of the working screw on the one hand and by increasing the outlet opening.

Preferably is at least one screw conveyor intended. By separating a screw conveyor from the working screw, which can be coupled together, for example, it is possible at a wear of Working worm exclusively to replace them, thereby saving material and costs. Preferably, a second drive is provided which the screw conveyor drives, the second drive is infinitely adjustable. For this Preferably, a hollow shaft is used in the screw conveyor to so the working screw through the first drive, passing through the hollow shaft coupled with the working worm to drive. In such a Arrangement of the screw conveyor and the working screw in alignment prefers the trains the respective snails adapted to each other, leaving a transition of the material coming from the screw conveyor promoted to the working screw becomes possible without further ado is.

Preferably are the screw conveyor and the working screw transversely to each other, in particular substantially perpendicular to each other, arranged. By this configuration is a particularly high throughput of solids or material possible.

Further Preferably, water outlets are in the casing intended. Preferably, the water outlets in the screw conveyor and / or at least partially arranged in the working screw. The water outlets in the area of the screw conveyor serve to drain off the water, that without further pressure application than the gravity of the solids solved becomes. The other water outlets are intended to remove the water, in particular by pressurization or is released after exclusion of moisture nests. To the water outlet If, in particular, a water drainage system is provided, of which the water outlets a component in each case.

If at least one closure element for closing or opening the outlets provided is, is an adaptability to the respective materials or moisture levels just possible. Preferably the closure element is an elongated Slide. The elongated one Slider is preferably moved by a control and / or regulating device.

Preferably an outlet area is provided which comprises the at least one opening, wherein in the outlet area, a conically tapered interior Exhaust element is provided. It is through this outlet element possible, to achieve a further pressure build-up and the throughput of material pretend. According to the material to be drained or the dehydrated solids it is particularly preferably possible, the angle of the inner cone of the outlet element and the length set or specify the outlet.

Preferably a folding mechanism is provided on the outlet member, by means of very quickly the throughput of material or solids varies or an intervention in the area of the working screw or replacing the working screw is made possible quickly. For example, it is preferably possible for the outlet element to be or multi-piece to provide so desired increase the throughput, for example, a part of the outlet element easy fold down, so a higher To get outlet cross section. It is also possible, instead a folding mechanism to provide other mechanisms such as quick-release screws for example, or a shifting mechanism.

If in particular, preferably a rotatable turret with different Provided outlet elements is a quick and easy Variation or change the respective outlet elements possible.

If preferably in the housing are provided in the range of at least one snail trains, is a increased Throughput of material or solids possible. Preferably enough the coincidence or the changing one Diameter of the core of the working screw up to the area of the working screw housing, in which the trains are provided. Preferably, the trains are spiral, resulting in a more uniform Material flow or solids flow results.

Preferably are the trains arranged straight and / or parallel to the axis of rotation. By these preferably Design is a cost effective Production possible.

Preferably a control and / or control device is provided which dependent on the level a feeder funnel, the moisture content of the solids and / or the need for dried Solids, the speed or the speeds of the Slugs controls and / or regulates. Preferably, in the level sensor In particular, an ultrasonic sensor provided by means of which the level of the funnel or the screw train can be measured.

The Invention will be described below without limiting the general inventive concept of exemplary embodiments with reference to the drawings described by way of example by the way in terms of the disclosure of all unspecified in the text details of the invention expressly is referenced. Show it:

1 an embodiment of the present invention in a schematic representation of three different directions, wherein 1a a side view is 1b a supervision and 1c a view from the back, and

2 a further embodiment of the invention in a schematic side view in cross-sectional view.

In The following figures are each the same or corresponding parts denoted by the same reference numerals, so that a renewed Presentation is omitted and only the deviations in These embodiments illustrated with respect to the first embodiment are explained:

1 shows an embodiment of the invention in three different views in a schematic representation.

1a shows a device for dewatering or dehydrating screenings. The screenings enter the funnel 24 brought in. Next is the screenings through the screw conveyor 13 in the direction of the working screw 10 promoted. Here, the screenings through the Druckspülungsdüsen 30 so rinsed that biological components are washed out on or in the screenings. By turning the screw conveyor 13 and the working screw 11 the material will be right in the 1a promoted. In the area of the screw conveyor 13 gets water through the water drainage system 21 derived. In the area of the working screw 10 that are in the case 11 is the pressed or dripping water from the material also in the water drainage system 21 drained. The water drainage system 21 can be one-piece or multi-piece. In 1a This system is designed in two parts.

The material eventually passes through the outlet element 22 ejected. The screw conveyor 13 is via the geared motor 20 driven. For the screw conveyor 13 and the working screw 10 a single drive may be provided as in 1a is shown. However, for example, two geared motors 20 be provided, in which case, for example, the drive of the working screw 10 through a hollow shaft of the screw conveyor 13 to be led. The decor itself is in 1a on a base 35 applied.

1b shows the device 1a from above and 1c shows the device 1a from the left side of the 1a considered.

The separation of the screw conveyor 13 and the working screw 10 is shown by a line between the two screws, which is arranged at the area at which the diameter of the working screw increases in the conveying direction for the first time. It can be clearly seen that the working worm essentially consists of four sections. The left-most section has an increasing diameter of the core of the working screw 10 , This is followed by a section which has a constant diameter of the core. Finally comes a section in which both the trains of the working screw 10 decrease in distance as the diameter of the core increases. Finally, a section can be seen in which the diameter of the core remains the same. The transitions from one section to the next section may preferably also be fluent. For example, a continuous balance may be provided, wherein the angle of the center is variable.

By This embodiment of the working screw is a continuous increase the pressure in the conveying direction possible. This is a low wear of the screws and in particular given the working screw, causing the device to itself longer Can be operated without maintenance or replacement of components.

In 2 is a further embodiment of the invention in a schematic side view in cross-sectional view. In this embodiment, only a part of the device is shown. Another auger, which is arranged transversely to the working screw, is in 2 not shown. This screw conveyor may preferably be arranged at an angle of 45 ° to 135 ° to the working screw.

In 2 is in particular the core diameter 16 more visible. In addition, it is shown that the working screw, which also has a conveyor section in this case, partially in a tunnel 40 is arranged. The working screw 10 of the 2 is roughly divided into three sections, namely a feed area 50 , a drainage area 51 and a pressing area 52 , These are essentially characterized by different core diameters and by a line in the core of the screw, which should represent the respective sections separated from each other. It should be noted here that the working worm be one piece can or in pieces. Also, it is good to see that in the drainage area 51 the volume 15 or volume sections due to an increasing diameter of the core of the working screw 10 reduced in the conveying direction. In the pressing area 52 are the features of the working screw 10 arranged closer together than the trains in the previous areas. As a result, a higher pressure is built up. Furthermore, in the pressing area 52 Trains 23 indicated the housing.

The outlet element 22 is in the embodiment of 2 formed in two pieces, for example, at high desired flow rate, the rightmost outlet or part of the outlet 22 can be removed. By appropriate choice of the outlet element 22 the degree of compaction, the amount of output and the degree of moisture of the ejected material can be specified or set.

Trains 23 of the housing can be imagined so that surveys are provided in certain areas on the inner wall of the housing, so that the working screw can still rotate. In other areas, a clearance between the width of the working screw and the housing is provided. For example, five trains may be provided.

By the uniform change the snail chamber, the concomitant pressure increase and turning the material, it is possible to get more water or liquid or dissipate fluid from the solids or the rake. By the sliding transition or the slow transfer into the high pressure range and construction of a kind of material wall shortly before The discharge of the material is a high pressure and high compression achieved, while at the same time a low wear of the elements the device is reached.

It is an adaptability of the device to the respective circumstances such as the starting material and the desired residual moisture of the ejected material readily possible. The here to consider Parameters are in particular the variation of the diameter of the core the working screw, the distance of the screw flights or the change the distance of the screw flights or Schneckenzüge and the Rotational speed of the screws. A simple rule is for example with a stepless drive of the screws possible.

Preferably Furthermore, a loosening system is provided in the hopper, which in the figures is not shown. Through this loosening system are the from the Rechengutwäsche or pre-drainage crushed coming Rechengutblöcke or the directly incoming material mixed and by a feeder screw supplied in a defined volume flow to the main system. It also serves the loosening system to prevent bridging and / or moisture pockets close up. The latter leads to a good pre-drainage. In the main system, which in particular includes the working screw is the screenings by means of such a working screw or press screw drained and the separation of the material and the removal of the wet solids reached.

The Wet binding contained in screenings is highly mechanical Art. These are surface moisture as well as capillary Moisture caused by adhesion forces on the surface and held in the pores of the rake. The pressure drainage removes the surface moisture and the water in the coarse, sometimes in the finer capillaries. In particular seasonal or weather-related material fluctuations is to catch and achieve an ideal degree of drainage, is the inventive device infinitely variable and / or controllable and with a buffer funnel fitted. Furthermore, the device is equipped with a central lubrication system provided, which is preferably computer controlled, so that the maintenance is reduced and ensures a constant availability is. By means of, for example, an ultrasound probe is preferably an input-dependent Control or regulation of the device and an operation with a lot low personnel expenditure, in particular a unmanned automatic operation, possible.

10

working worm

11

casing

12

opening

13

Auger

15

volume

16

core diameter

20

gearmotor

21

Drainage system

22

outlet

23

train

24

funnel

30

Pressure cleaning nozzles

35

undercarriage

40

tunnel

50

feeding

51

drainage area

52

Press area

Claims (17)

Device for dewatering solids separated from fluids, in particular Re chengut, comprising a pressing device with at least one working screw ( 10 ), which at least partially from a housing ( 11 ), wherein the housing ( 11 ) following the working screw ( 10 ) in the conveying direction at least one opening ( 12 ), characterized in that the screw flights of the working screw ( 10 ) on a core ( 16 ), wherein the diameter of the core ( 16 ) of the working screw ( 10 ) increases in the conveying direction. Device according to claim 1, characterized in that a volume ( 15 ) is defined between the working screw and the housing and that the volume ( 15 ) decreases in the conveying direction at least in one section. Device according to claim 2, characterized that the volume reduction is continuous. Device according to one of claims 1 to 3, characterized in that a first drive ( 20 ) is provided, the at least one working screw ( 10 ), the first drive ( 20 ) is infinitely adjustable. Device according to one or more of claims 1 to 4, characterized in that at least one screw conveyor ( 13 ) is provided. Device according to claim 5, characterized in that a second drive is provided which the screw conveyor ( 13 ), wherein the second drive is infinitely adjustable. Device according to claim 5 and / or 6, characterized in that the working screw ( 10 ) and the screw conveyor ( 13 ) are arranged transversely to each other, in particular substantially perpendicular to each other. Device according to one or more of claims 1 to 7, characterized in that water outlets ( 21 ) in the housing ( 11 ) are provided. Device according to claim 8, characterized in that the water outlets ( 21 ) in the area of the screw conveyor ( 13 ) and / or at least partially in the area of the working screw ( 10 ) are arranged. Device according to claim 8 and / or 9, characterized in that at least one closure element for closing or opening the outlets ( 21 ) is provided. Device according to claim 10, characterized that the closure element is an elongated Slider is. Device according to one or more of claims 1 to 11, characterized in that an outlet region is provided which comprises the at least one opening, wherein in the outlet region a conically tapering outlet element ( 22 ) is provided. Device according to claim 12, characterized in that a folding mechanism on the outlet element ( 22 ) is provided. Device according to one or more of claims 1 to 13, characterized in that a particular rotatable turret with different outlet elements ( 22 ) is provided. Device according to one or more of claims 1 to 14, characterized in that in the housing ( 11 ) in the region of at least one screw ( 10 . 13 ) Trains ( 23 ) are provided. Device according to claim 15, characterized in that the trains ( 23 ) are spiral. Device according to one or more of claims 4 to 16, characterized in that a control and / or control device is provided which, depending on the filling level of a feed hopper ( 24 ), the moisture content of the solids and / or the need for dried solids, the speed or the speeds of the screws ( 10 . 13 ) controls and / or regulates.